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10 pages, 782 KiB  
Article
Effects of Limbs’ Spasticity on Spinopelvic Alignment in Post-Stroke Patients: A Cross-Sectional Study
by Luciano Bissolotti, Alice Brojka, Marika Vezzoli, Stefano Calza, Federico Nicoli, Carlos Romero-Morales and Jorge Hugo Villafañe
J. Clin. Med. 2024, 13(13), 3840; https://doi.org/10.3390/jcm13133840 - 29 Jun 2024
Viewed by 953
Abstract
Objectives: This study aimed to determine the impacts of upper and lower limb (UL and LL) spasticity and impairment on spinal alignment in chronic post-stroke patients. Methods: A total of 45 consecutive chronic post-stroke patients, 18 women and 27 men, from [...] Read more.
Objectives: This study aimed to determine the impacts of upper and lower limb (UL and LL) spasticity and impairment on spinal alignment in chronic post-stroke patients. Methods: A total of 45 consecutive chronic post-stroke patients, 18 women and 27 men, from 18 to 70 years old who presented post-stroke hemiparesis were recruited in this cross-sectional study. The clinical assessment included the Modified Ashworth Scale (UL-MAS and LL-MAS spasticity), Upper Limb Motricity Index (UL-MI), FAST-UL, and Five Times Sit-to-Stand Test (5T-STS); the Associated Reaction Rating Scale was used to measure associated reactions in the hemiparetic UL, the plumb line distance from the spinous process of C7 on the sagittal (PL-C7s) and frontal plane (Pl-C7f), the kyphosis apex (PL-AK), and the spinous process of L3 (PL-L3). Angular measures of spinal alignment were measured by a Bunnell scoliometer™ (angle of trunk rotation—ATR) and a gravity-dependent inclinometer (inclination at C7-T1 and T12-L1). Results: In chronic post-stroke patients, there was found to be an association between the 5T-STS and PL-C7f (β = 0.41, p = 0.05) and the angle of inclination at T12-L1 (β = 0.44, p = 0.01). The FAST-UL correlated with PL-C7f (β = −0.41, p = 0.05), while the UL-MI correlated with this last parameter (β = −0.36, p = 0.04) and the ATR (β = −0.31, p = 0.05). The UL-MAS showed correlation with the ATR (β = 0.38, p = 0.01). Conclusions: The results lead to the possibility that, in chronic post-stroke patients, spinal misalignment on the frontal and sagittal plane is associated both with strength impairment and UL spasticity. The improvement or restoration of spinopelvic parameters can take advantage of therapeutic interventions targeted at motor improvement and spasticity reduction of the hemiparetic side. Full article
(This article belongs to the Special Issue Spine Surgery and Rehabilitation: Current Advances and Future Options)
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Figure 1
<p>(<b>a</b>,<b>b</b>): Correlation plot with all the quantitative variables. This upper triangular matrix reports in each cell the spearman correlation (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>ρ</mi> </mrow> <mrow> <mi>s</mi> </mrow> </msub> </mrow> </semantics></math>) coefficient computed between couples of items. The background of the cells is coloured of blue if the relationship is positive (<math display="inline"><semantics> <mrow> <msub> <mrow> <mn>0</mn> <mo>≤</mo> <mi>ρ</mi> </mrow> <mrow> <mi>s</mi> </mrow> </msub> <mo>≤</mo> <mn>1</mn> </mrow> </semantics></math>); otherwise, cell is coloured of red (<math display="inline"><semantics> <mrow> <msub> <mrow> <mo>−</mo> <mn>1</mn> <mo>≤</mo> <mi>ρ</mi> </mrow> <mrow> <mi>s</mi> </mrow> </msub> <mo>&lt;</mo> <mn>0</mn> </mrow> </semantics></math>). The colors intensity are proportional to the magnitude of (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>ρ</mi> </mrow> <mrow> <mi>s</mi> </mrow> </msub> </mrow> </semantics></math>), white cells corresponds to correlations which are not significant different from 0 (<span class="html-italic">p</span>-value &gt; 0.05).</p>
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8 pages, 7483 KiB  
Communication
Water Supply and Firefighting: Early Lessons from the 2023 Maui Fires
by Robert B. Sowby and Braxton W. Porter
Water 2024, 16(4), 600; https://doi.org/10.3390/w16040600 - 18 Feb 2024
Cited by 1 | Viewed by 2755
Abstract
Even though drinking water utilities are not meant to fight wildfires, they quickly become stakeholders, if not first responders, when their resources are needed for firefighting. The August 2023 wildfires on the island of Maui, Hawaii, USA, have highlighted weaknesses at this intersection. [...] Read more.
Even though drinking water utilities are not meant to fight wildfires, they quickly become stakeholders, if not first responders, when their resources are needed for firefighting. The August 2023 wildfires on the island of Maui, Hawaii, USA, have highlighted weaknesses at this intersection. While attention has focused on the wildfire causes or water quality impacts afterward, few studies have analyzed the response. We review this extreme case to support disaster-response lessons for water utilities and to guide further research and policy. First, emergency water releases were not available in a timely manner. Second, fire and wind toppled power lines, causing power outages that inhibited pumping water. Third, many structures were a total loss despite water doused on them, consuming valuable water. Finally, water was lost through damaged premise plumbing in burned structures, further reducing system pressure. These conditions emphasize that water utilities need to access emergency water supplies quickly, establish reliable backup electricity, coordinate with firefighters on priority water uses, and shut valves in burned areas to preserve water. While further research will certainly follow, we present these early lessons as starting points. Full article
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<p>Overview of Maui fires.</p>
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<p>Fire damage in Lahaina (photo by State Farm via Flickr. CC BY 2.0).</p>
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<p>A typical Hawaiian fire hydrant (photo by NAVFAC via Flickr. CC BY 2.0).</p>
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27 pages, 12078 KiB  
Article
The Plumb-Line Matching Algorithm for UAV Oblique Photographic Photos
by Xinnai Zhang, Jiuyun Sun, Jingxiang Gao, Kaijie Yu and Sheng Zhang
Remote Sens. 2023, 15(22), 5290; https://doi.org/10.3390/rs15225290 - 9 Nov 2023
Viewed by 1396
Abstract
Building facades has always been a challenge for feature matching in oblique photogrammetry due to weak textures, non-Lambertian objects, severe occlusion, and distortion. Plumb lines are essential building geometry structural feature lines in building facades, which show strong spatial relevance to these problems. [...] Read more.
Building facades has always been a challenge for feature matching in oblique photogrammetry due to weak textures, non-Lambertian objects, severe occlusion, and distortion. Plumb lines are essential building geometry structural feature lines in building facades, which show strong spatial relevance to these problems. Achieving plumb line matching has great application potential for optimizing the process and products of oblique photogrammetry. Thus, we proposed a novel matching algorithm for plumb lines based on spatial and color hybrid constraints according to its central projection imaging characteristics. Firstly, based on vanishing point theory, the plumb lines from photos were back-calculated to determine the matching target set; secondly, the property of its large elevation ranges was exploited to calculate the homonymous points as spatial constraints by projecting plumb lines onto the stratified spatial planes; thirdly, the neighboring primary colors on both sides of the plumb lines were extracted as feature descriptors and compared by colorimetry; then, the greedy strategy was employed to successively filter out the locally optimal solutions satisfying the spatial and color hybrid constraints to complete the initial matching; finally, the intersection-over-union analysis of the solution plane and the verticalness evaluation of the matching results were implemented to eliminate errors. The results show that the proposed algorithm can achieve an average accuracy of 97.29% and 78.41% in the forward and lateral overlap experiments from multi-scenes, respectively, displaying a strong adaptability to poor texture, inconsistency, and distortion. In conclusion, thanks to the plumb-line-oriented matching strategy, this algorithm owns inherent advantages in theory and computational complexity. It is suitable for all building-oriented oblique photogrammetry tasks and is highly worthy of promotion and application. Full article
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Graphical abstract

Graphical abstract
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<p>Examples of oblique photos and building 3D real-scene models. (<b>a</b>,<b>b</b>) show two examples with different styles of photographs and 3D real scene models, respectively. Building facade is always a weak region for traditional matching methods in oblique photogrammetry due to the many challenges, such as occlusion, deformation, weak texture, repetitive texture, and non-Lambertian objects. Therefore, the facade of the real 3D building model based on oblique photogrammetry generally has too many nodes and distorted structures. As can be seen, the plumb lines in the image generally appear in pairs, with their middle positions generally building structures such as exterior windows and terraces (where the glass is typically non-Lambertian object), and the rest of the neighborhood generally comprises walls (wall textures are mostly weak and repetitive). Therefore, the plumb lines have a close spatial relationship with these problem regions in both images and models.</p>
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<p>Examples of plumb lines in the photos from oblique photography tasks (screenshot at the same scale); (<b>a</b>,<b>c</b>) are from lateral overlap photo pair; (<b>b</b>,<b>d</b>) are from forward overlap photo pair. Plumb lines are particular line segments widely distributed in human activity scenes, especially on the facades of structures, e.g., building corners and door or window edges.</p>
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<p>Overall flowchart of the algorithm.</p>
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<p>Schematic of the vanishing points of parallel spatial lines in the photos. Extensions of parallel structural lines of the building intersect at the same vanishing point.</p>
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<p>Examples of plumb line back-calculation results in the photos. The red lines are the plumb line that back-calculates through the photo nadir point; (<b>a</b>,<b>c</b>) show two perfect back-calculation results where the plumb lines are extracted correctly. In comparison, some lines are incorrectly identified as plumb lines in (<b>b</b>), which are coincidentally oriented to the camera center.</p>
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<p>Schematic diagram of SPPs calculation. The yellow and green lines are the projections of the two photo line segments in different spatial planes using Equation (3); the “+” red circle represents the true SPPs, and the “x” red circle represents the false SPPs.</p>
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<p>Examples of the SPPs calculation process. The purple points are SPPs, and the spatial line segment elevation increases continuously from green to red. When the elevation of the spatial plane is within the elevation range of the plumb line, the homologous plumb lines will intersect, producing true SPPs. Therefore, SPPs can be used as positional constraints to determine the possible set of homologous plumb line pairs. But adjacent plumb lines may also intersect in the spatial plane, producing false SPPs.</p>
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<p>Examples of both-side neighborhood pixels of the plumb lines. Color is an essential feature of line-segment neighborhoods. Plumb lines mostly appear in the structural and color transition regions, with poor texture neighborhoods; (<b>a</b>,<b>b</b>) are from the forward and lateral overlap photos. Complex variations in the neighborhoods of the homonymous plumb lines lead to worse one-to-one correspondences between pixels. Thus, classical approaches, e.g., MSLD and LBD, are not applicable.</p>
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<p>Schematic diagram of plumb-line neighborhood pixels partitioning and extraction based on the photo polar coordinate system. The black line is the target plumb line, and the purple line is the other plumb line. The target is the plumb line <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> with yellow fluorescence, and <math display="inline"><semantics> <mrow> <msubsup> <mi>R</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> is the observation vector from the photo nadir point to the target. The <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> neighborhood pixels are partitioned by locating on the <math display="inline"><semantics> <mrow> <msubsup> <mi>R</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> clockwise or anti-clockwise region and are extracted by rotating <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> around <math display="inline"><semantics> <mrow> <msubsup> <mi>p</mi> <mi>l</mi> <mrow> <mi>p</mi> <mi>n</mi> <mi>p</mi> </mrow> </msubsup> </mrow> </semantics></math>. The green and blue are the partitioning and extraction results of <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> clockwise and anti-clockwise neighborhood pixels, respectively.</p>
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<p>Schematic diagram of the consistency of the plumb-line neighborhoods under multi-view observation. When the observation view changes, the blue, red, and cyan plumb lines maintain at least single-side neighborhood consistency.</p>
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<p>Schematic diagram of the visible neighborhood of the plumb line under different observations. Colored arrows represent observation vectors. When the two observation vectors are located in the Q2 and Q4 quadrants (red arrows), respectively, the observations of the plumb-line neighborhood on both sides are inconsistent.</p>
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<p>Schematic diagram of plumb-line pairs forward intersection. <math display="inline"><semantics> <mrow> <mi>K</mi> <msubsup> <mi>P</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <mi>K</mi> <msubsup> <mi>P</mi> <mi>r</mi> <mi>j</mi> </msubsup> </mrow> </semantics></math> are the spatial solution triangles of plumb lines <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>l</mi> <mi>i</mi> </msubsup> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msubsup> <mi>l</mi> <mi>r</mi> <mi>j</mi> </msubsup> </mrow> </semantics></math>, respectively.<math display="inline"><semantics> <mrow> <mo> </mo> <msubsup> <mi>L</mi> <mrow> <mi>l</mi> <mi>r</mi> </mrow> <mrow> <mi>i</mi> <mi>j</mi> </mrow> </msubsup> <mo>,</mo> <mo> </mo> <msubsup> <mi>L</mi> <mrow> <mi>r</mi> <mi>l</mi> </mrow> <mrow> <mi>j</mi> <mi>i</mi> </mrow> </msubsup> </mrow> </semantics></math> are their intersection lines with each other, which display certain overlapping and deviate from the standard spatial plumb line <math display="inline"><semantics> <mrow> <msup> <mi>L</mi> <mrow> <mi>i</mi> <mi>j</mi> </mrow> </msup> </mrow> </semantics></math> with angular <math display="inline"><semantics> <mo>∀</mo> </semantics></math>.</p>
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<p>Diagram of the experimental scenes. Photo (<b>a</b>) shows a township scene, in which the closely distributed buildings are of a single type, with an elevation range of 33.1–45.3 m; Photo (<b>b</b>) is a rural scene, in which the buildings are sparsely distributed and diverse in types, with an elevation range of 31.3–40.8 m; Photo (<b>c</b>) shows a factory scene, in which the buildings are distributed independently and are of complex types, with an elevation range of 30.6–51.5 m.</p>
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<p>Sample diagrams of buildings in different scenarios. The factory scene (<b>c</b>) contains taller factory dormitory buildings, medium-height office buildings, and lower factory buildings, all of which are distinctly different in terms of architectural appearance and building height; the township scene (<b>a</b>) and rural scene (<b>b</b>) do not vary much in height, but each has its own unique style in terms of building structure. Building facades in all scenes have weak textures, repeated textures, non-Lambertian objects (external windows), and occluded deformed regions.</p>
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<p>Schematic diagram of the UAV oblique-photography flight strips and the selection of experimental photo pairs. The green image pairs are forward-overlapping photo pairs (from the same flight strip, one in front and one behind), and the blue image pairs are lateral overlapping photo pairs (from neighboring flight strips, a combination of offsets perpendicular to and along the flight strip is generally present, but the former is generally much larger than the latter).</p>
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<p>Matching results of township scene a. In the DOM vision, the green circles and red crosses correspond to the SPPs (which are also the projection results of the spatial plumb lines generated by the forward intersection of the homologous plumb-line pairs) corresponding to the correct and erroneous plumb-line pair matching results, respectively. In the Photo and Detail visions, the homologous plumb-line pairs are shown in the same color. In the Photo vision, the green and red connecting lines correspond to the correct and erroneous matching results, respectively. <a href="#remotesensing-15-05290-f017" class="html-fig">Figure 17</a> and <a href="#remotesensing-15-05290-f018" class="html-fig">Figure 18</a> are similarly represented as such.</p>
Full article ">Figure 16 Cont.
<p>Matching results of township scene a. In the DOM vision, the green circles and red crosses correspond to the SPPs (which are also the projection results of the spatial plumb lines generated by the forward intersection of the homologous plumb-line pairs) corresponding to the correct and erroneous plumb-line pair matching results, respectively. In the Photo and Detail visions, the homologous plumb-line pairs are shown in the same color. In the Photo vision, the green and red connecting lines correspond to the correct and erroneous matching results, respectively. <a href="#remotesensing-15-05290-f017" class="html-fig">Figure 17</a> and <a href="#remotesensing-15-05290-f018" class="html-fig">Figure 18</a> are similarly represented as such.</p>
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<p>Matching results of rural scene b.</p>
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<p>Matching results of rural scene b.</p>
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<p>Matching results of factory scene c.</p>
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<p>Matching results of factory scene c.</p>
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<p>Folding line graph of quantity and accuracy changes in the proposed algorithm.</p>
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<p>Schematic of the plumb-line projection in the space plane in the forward and lateral overlap experiments.</p>
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18 pages, 16969 KiB  
Article
An Algorithm for Building Exterior Facade Corner Point Extraction Based on UAV Images and Point Clouds
by Xinnai Zhang, Jiuyun Sun and Jingxiang Gao
Remote Sens. 2023, 15(17), 4166; https://doi.org/10.3390/rs15174166 - 24 Aug 2023
Cited by 1 | Viewed by 1321
Abstract
The high-precision building exterior facade corner point (BEFCP) is an essential element in topographic and cadastral surveys. However, current extraction methods rely on the interactions of humans with the 3D real-scene models produced by unmanned aerial vehicle (UAV) oblique photogrammetry, which have a [...] Read more.
The high-precision building exterior facade corner point (BEFCP) is an essential element in topographic and cadastral surveys. However, current extraction methods rely on the interactions of humans with the 3D real-scene models produced by unmanned aerial vehicle (UAV) oblique photogrammetry, which have a high workload, low efficiency, poor precision, and cannot satisfy the requirements of automation. The dense point cloud contains discrete 3D building structure information. Still, it is challenging to accurately filter out the partial point cloud characterizing the building structure from it in order to achieve BEFCP extraction. The BEFCPs are always located on the plumb line of the building’s exterior wall. Thus, this paper back-calculated the plumb line from the image and designed a photographic ray corresponding to the image point and point cloud intersection point calculation algorithm to recover its approximate spatial position in order to successfully extract the accurate point cloud in the building structure neighborhood. It then utilized the high signal-to-noise ratio property of the point cloud as a base to eliminate the noise points and, finally, accurately located the building exterior façade corner points by recovering the building structure through segmental linear fitting of the point cloud. The proposed algorithm conducted automated building exterior facade corner point extraction via both of planar-to-stereo and rough-to-precise strategies, reached a 92.06% correctness rate and ±4.5 cm point mean square location error in the experiment, and was able to extract and distinguish the building exterior facade corner points under eaves obstruction and extreme proximity. It is suitable for all high-precision surveying and mapping tasks in building areas based on oblique photogrammetry, which can effectively improve the automation of mapping production. Full article
(This article belongs to the Section Engineering Remote Sensing)
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<p>Examples of BEFCPs. The red lines are the corner lines of the exterior facade of the building, and the corresponding points of the corner lines in the XY plane are BEFCPs. A BEFCP is not the corner point of the building footprint. It is usually located on the plumb line of the building facade under the roof and is the basis for accurately measuring the area of land occupied by a building. In large-scale topographic mapping, cadastral surveying, and other surveying and mapping production tasks in China, the primary production method for BEFCPs is for indoor workers to operate the real-scene 3D mapping software, determine the wall plane using three or five points, and then determine the BEFCP using the intersection line of the wall planes. The buildings have complex structures and are close to each other (as shown in (<b>c</b>)), and BECFP is occluded by eaves and trees (as shown in (<b>a</b>,<b>b</b>)). Accurately retrieving the point cloud representing BEFCP (point cloud in the neighborhood with the red line) and recovering the building structure from discrete point clouds are the key to locating BEFCPs.</p>
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<p>Examples of plumb line extensions intersecting at the photo nadir point. Aerial imaging belongs to the central projection, where the projections of parallel lines in the world coordinate system on the image intersect at the vanishing point. Plumb lines are a unique set of parallel lines in the real world, and their extensions intersect at the photo nadir point in the image space.</p>
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<p><b>The</b> flow of BEFCP recognition algorithm.</p>
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<p>Schematic diagram of line segment extraction: (<b>a</b>) is a screenshot of the details of straight lines extracted directly from the original image using the LSD, while (<b>b</b>) performs BF before extracting the straight lines. The red circles are areas of significant contrast where the BF enhances most of the edges of the building structure and effectively blurs the building interior and tree textures.</p>
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<p>Examples of back-calculation and spatial mapping of plumb lines. Figures (<b>lb</b>) and (<b>rb</b>) are enlargements of the red boxes in figures (<b>la</b>) and (<b>ra</b>), respectively. Images preserve tight texture features clearly distinguishing spatially adjacent building structure feature lines, providing accurate spatial indices for extracting point clouds characterizing building structures after the plumb lines are mapped to space.</p>
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<p>Algorithm flow of coordinate calculation of object point corresponding to the image point, where “a” is the image point, “A” is the object point corresponding to “a”, and “S” is the photo-graphic ray connecting “A” and “a”.</p>
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<p>Examples of the point cloud extraction, filtering, and fitting process. After dimensionality reduction, the original point clouds show stronger spatial aggregation, and the point cloud filtering algorithm eliminates its noise.</p>
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<p>BEFCP determination and positioning algorithm flow.</p>
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<p>Situation and location maps of the experimental regions.</p>
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<p>Experimental image distribution maps. The distribution of 27 experimental images in test areas (<b>A</b>,<b>B</b>). The red numbers are the image index numbers, the red dot is the photography center, and the yellow line and green quadrilateral are the shooting poses.</p>
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<p>Distributions of BEFCP detection results and checkpoints. The green and red circles are the correctly and incorrectly detected BEFCPs, respectively, and the red crosses are the selected positional accuracy checkpoints.</p>
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<p>Statistical chart of the detected amount of BEFCPs.</p>
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<p>Examples of correct detection results. The red line and the red “+” are the BEFCP’s mapping results in the image, the point cloud, and the DOM, respectively. The top and bottom exterior facade corner points in a high-rise building with extreme spatial proximity are correctly distinguished and identified, as shown in (<b>B1</b>). The corner points under the roof are also accurately fitted and identified, as shown in (<b>A1</b>,<b>B2</b>). The BEFCP is still successfully detected when the composition of the exterior facade of the building is complex, and the plumb line where the BEFCP was located was only partially extracted, as shown in (<b>A2</b>).</p>
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22 pages, 16212 KiB  
Article
DInSAR Data Reveal an Intriguing Contemporaneous Onset of Deep Deflation below Vesuvio and the Ongoing Campi Flegrei Uplift
by Antonella Amoruso and Luca Crescentini
Remote Sens. 2023, 15(12), 3038; https://doi.org/10.3390/rs15123038 - 10 Jun 2023
Cited by 2 | Viewed by 1537
Abstract
Campi Flegrei and Vesuvio volcanoes are only about 25 km apart, located on opposite sides of the densely inhabited area of Naples (Italy). Since neighbouring volcanoes may influence each other’s activity, it is of great interest to identify signs of any mutual interaction [...] Read more.
Campi Flegrei and Vesuvio volcanoes are only about 25 km apart, located on opposite sides of the densely inhabited area of Naples (Italy). Since neighbouring volcanoes may influence each other’s activity, it is of great interest to identify signs of any mutual interaction between Campi Flegrei and Vesuvio, or at least note coincidences in their recent deformation dynamics. After a large uplift, Campi Flegrei was generally subsiding from 1985 to 2001, while it has been uplifting—probably driven by deep magma inflation—at an accelerating rate since then. Here, we analysed the ground displacement in the whole Vesuvian area and its surroundings around the early 2000s using 1993–2010 ERS/ENVISAT ascending- and descending-orbit line-of-sight displacements obtained through the Small BAseline Subset Differential Synthetic Aperture Radar Interferometry technique. Although ground deformation is slow—a few millimetres per year—Empirical Orthogonal Function analysis shows a sudden trend change around 2001. Pre-2001 velocity maps confirm previously published results: subsidence mainly occurred inside the caldera rim—probably because of the sliding and compaction of young incoherent materials—and in a few spots around 10 km from the summital crater; eastward displacement occurred in a lobe east of Vesuvio, and westward displacement occurred in a lobe west of Vesuvio, as in the case of the spreading of the volcanic edifice and/or extensional tectonics. We attribute the subsidence spots to the previous high local number of new buildings per year. Post-2002 velocity maps provide evidence of a very different scenario: general subsidence in the whole Vesuvian area, westward displacement in a lobe east of Vesuvio, and eastward displacement in a lobe west of Vesuvio. This last arrangement of the ground displacement field is made even clearer by subtracting the post-2002 velocity from the pre-2001 value. The results of our analyses are consistent with the deflation of a deep pressurised source. Additionally, Vesuvio’s deep seismicity decreased at the beginning of 2002. The coincidence between the transition from deflation to inflation at Campi Flegrei and the onset of deflation below Vesuvio may suggest the possible transfer of magma and/or magmatic fluids between the two plumbing systems. Full article
(This article belongs to the Section Earth Observation for Emergency Management)
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Graphical abstract

Graphical abstract
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<p>Map of Campi Flegrei and Vesuvio volcanoes, UTM WGS84 33N coordinates. (<b>a</b>) Topography; colours indicate altitudes [<a href="#B13-remotesensing-15-03038" class="html-bibr">13</a>]. Black dots and labels: L, LICO cGPS station, here used as a reference for comparing DInSAR and cGPS displacements; R, Rione Terra, in the area of maximum vertical movement of Campi Flegrei; S, Solfatara crater; P, Pisciarelli fumaroles; A, Agnano plain. (<b>b</b>) Satellite image (map data: Google, ©2022 Landsat/Copernicus) showing the densely inhabited urban area of Naples. Cyan and yellow discontinuous lines with triangles indicate the borders of the Campanian Ignimbrite (CI, about 39 ka) and Neapolitan Yellow Tuff (NYT, about 15 ka) caldera collapses, respectively (adapted from [<a href="#B14-remotesensing-15-03038" class="html-bibr">14</a>]). The white curve indicates the Mt Somma caldera rim. The red polygon encloses the area that is used here as reference for the analysis of DInSAR data.</p>
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<p>Ground level changes at Rione Terra (R in <a href="#remotesensing-15-03038-f001" class="html-fig">Figure 1</a>a)—i.e., in the area of maximum vertical displacement—from 1980 to 2022. Red dots, levelling data [<a href="#B15-remotesensing-15-03038" class="html-bibr">15</a>]. Green and magenta pluses, approximate median vertical displacement (<a href="#sec2dot1-remotesensing-15-03038" class="html-sec">Section 2.1</a>) inside a 200 m radius circular area from ERS/ENVISAT and Sentinel-1A images, respectively. Blue crosses, GPS vertical displacement [<a href="#B11-remotesensing-15-03038" class="html-bibr">11</a>].</p>
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<p>Times of displacement data. Red and blue circles, acquisition dates of the ascending- and descending-orbit images and times of the corresponding LOS displacements. Green circles, times of the computed approximate eastward and upward displacements.</p>
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<p>Synthetic ground displacements caused by the deflation of a very small (point) pressurised spherical cavity (Mogi source) embedded in a homogeneous elastic half-space whose Poisson’s ratio is 0.25. LOS incidence and azimuthal angles are 23.9° and −12°, respectively, for the ascending orbit and 20.5° and 192° for the descending orbit. Displacements are divided by the absolute value of the vertical displacement at (0,0), thus making all the plots independent of the source volume change. Coordinates (<span class="html-italic">x</span>, <span class="html-italic">y</span>) are normalised by the source depth <span class="html-italic">d</span>, thus making all the plots independent of the source depth. The contour interval is 0.1. The black star in (0,0) indicates the source centre. (<b>a</b>) Ascending-orbit LOS displacement. (<b>b</b>) Descending-orbit LOS displacement. (<b>c</b>) Upward displacement. (<b>d</b>) Eastward displacement; northward displacement can be obtained after rotating the map by 90° in the anticlockwise direction. (<b>e</b>) Approximate upward displacement estimated from (<b>a</b>,<b>b</b>). (<b>f</b>) Approximate eastward displacement estimated from (<b>a</b>,<b>b</b>). Approximate upward displacements (<b>e</b>) are very similar to the exact synthetic ones (<b>c</b>), but contour lines are shifted southward (i.e., toward negative <span class="html-italic">y</span>). The approximate eastward displacement map (<b>f</b>) is practically indistinguishable from the exact synthetic eastward displacements (<b>d</b>).</p>
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<p>Synthetic ground displacements caused by the deflation of a very small (point) pressurised spherical cavity (Mogi source) embedded in a homogeneous elastic half-space whose Poisson’s ratio is 0.25. LOS incidence and azimuthal angles are 23.9° and −12°, respectively, for the ascending orbit and 20.5° and 192° for the descending orbit. Displacements are divided by the absolute value of the vertical displacement at (0,0), thus making all the plots independent of the source volume change. Coordinates (<span class="html-italic">x</span>, <span class="html-italic">y</span>) are normalised by the source depth <span class="html-italic">d</span>, thus making all the plots independent of the source depth. The contour interval is 0.1. The black star in (0,0) indicates the source centre. (<b>a</b>) Ascending-orbit LOS displacement. (<b>b</b>) Descending-orbit LOS displacement. (<b>c</b>) Upward displacement. (<b>d</b>) Eastward displacement; northward displacement can be obtained after rotating the map by 90° in the anticlockwise direction. (<b>e</b>) Approximate upward displacement estimated from (<b>a</b>,<b>b</b>). (<b>f</b>) Approximate eastward displacement estimated from (<b>a</b>,<b>b</b>). Approximate upward displacements (<b>e</b>) are very similar to the exact synthetic ones (<b>c</b>), but contour lines are shifted southward (i.e., toward negative <span class="html-italic">y</span>). The approximate eastward displacement map (<b>f</b>) is practically indistinguishable from the exact synthetic eastward displacements (<b>d</b>).</p>
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<p>Comparison of levelling data [<a href="#B34-remotesensing-15-03038" class="html-bibr">34</a>] and ERS/ENVISAT approximate upward displacements. First, we referenced DInSAR LOS displacements to their median value within a circular area, 250 m in radius, centred on the NA001 reference levelling benchmark (green dot in (<b>a</b>)). Then, we obtained the time series of the DInSAR approximate upward displacements by combining LOS displacements as if northward ground displacement did not contribute and computing the median values within circular areas, 250 m in radius, centred on the levelling benchmarks. (<b>a</b>) Blue dots and labels, levelling benchmarks whose altitude time series are plotted with respect to NA001 in [<a href="#B34-remotesensing-15-03038" class="html-bibr">34</a>]. (<b>b</b>–<b>q</b>) Blue dots, levelling data; red dots, DInSAR approximate upward displacements. Levelling data errors are lower than <math display="inline"><semantics> <mrow> <mo>±</mo> <mn>2.5</mn> <mo>×</mo> <msqrt> <mi>L</mi> </msqrt> </mrow> </semantics></math> mm, where <span class="html-italic">L</span> is the length in kilometres of each levelling section. The vertical bar corresponds to 1 cm vertical displacement.</p>
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<p>Comparison of cGPS [<a href="#B11-remotesensing-15-03038" class="html-bibr">11</a>] and ERS/ENVISAT DInSAR displacements. First, we referenced DInSAR displacements to the median value within a circular area, 500 m in radius, centred on the LICO GPS station (L in <a href="#remotesensing-15-03038-f001" class="html-fig">Figure 1</a>); LICO is far from Campi Flegrei and Vesuvio and has a small almost-constant velocity with respect to six stations located outside the Neapolitan volcanic area, whose velocities are expected to reflect the regional tectonic motion [<a href="#B11-remotesensing-15-03038" class="html-bibr">11</a>]. Then, we added the LICO GPS linear trends—0.05 cm/year and −0.12 cm/year along the ascending- and descending-orbit LOS directions, respectively—to each DInSAR displacement time series, obtained by computing the median values within circular areas, 500 m in radius, centred on the cGPS stations. (<b>a</b>) Blue dots and labels, cGPS Vesuvio stations that are located in areas covered by SAR data and started operating before 2006 [<a href="#B11-remotesensing-15-03038" class="html-bibr">11</a>]. (<b>b</b>–<b>m</b>) Blue dots, daily cGPS displacements projected along DInSAR LOS directions; red dots, DInSAR displacements. The vertical bar corresponds to 1 cm displacement.</p>
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<p>Mean displacement rate from SAR data between 1992 and 2010. (<b>a</b>) Ascending orbit, LOS direction. (<b>b</b>) Descending orbit, LOS direction. (<b>c</b>) Approximate upward displacement obtained by combining LOS displacements as if northward ground displacement did not contribute. (<b>d</b>) Approximate eastward displacement obtained by combining LOS displacements as if northward ground displacement did not contribute. Each velocity component is referenced to its median value inside the area enclosed by the red polygon. Magenta stars in (<b>a</b>–<b>d</b>) give the centre of the circular areas used for the EOF analyses. The two black circles in (<b>c</b>) indicate the two most prominent subsidence spots around Vesuvio (see also <a href="#remotesensing-15-03038-f008" class="html-fig">Figure 8</a>). No significant feature is visible in (<b>d</b>) close to those two subsidence spots.</p>
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<p>Rate of construction of new buildings in the most prominent subsidence spots around Vesuvio. (<b>a</b>) Same as <a href="#remotesensing-15-03038-f007" class="html-fig">Figure 7</a>c; in addition, dark red and light green dots as well as labels “1” and “2” indicate the two subsidence spots bounded by the black circles in <a href="#remotesensing-15-03038-f007" class="html-fig">Figure 7</a>c; the magenta dot and label “3” indicate an additional further-north subsidence spot. Black polygons surround the municipalities of Volla (V), Cercola (C), and San Gennaro Vesuviano (S). The magenta rectangle encloses the area zoomed in (<b>d</b>,<b>e</b>). (<b>b</b>) Approximate mean upward displacements within the three circular areas, 500 m in radius, centred on the three dots—dark red, light green, and magenta—in (<b>a</b>). (<b>c</b>) Urbanisation rates (number of new buildings per year) at Volla, Cercola, and San Gennaro Vesuviano during different time periods (data from the Italian National Institute for Statistics [<a href="#B63-remotesensing-15-03038" class="html-bibr">63</a>]). (<b>d</b>) December 1985 satellite image of the area enclosed by the magenta rectangle in (<b>a</b>) (map data: Google, ©2022 Landsat/Copernicus). (<b>e</b>) August 2002 satellite image of the area enclosed by the magenta rectangle in (<b>a</b>) (map data: Google, ©2022 Landsat/Copernicus).</p>
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<p>Expansion Coefficients (ECs) and eigenvalues for the first EOF modes. The EOF analysis of the 1992–2010 displacement time series was carried out inside a circular area of radius R centred on the magenta star in <a href="#remotesensing-15-03038-f007" class="html-fig">Figure 7</a>. The error bars in the eigenvalue plots give uncertainties. (<b>a</b>,<b>b</b>) Joint EOF analysis of ascending and descending LOS displacements, R = 15,000 m. (<b>c</b>,<b>d</b>) Joint EOF analysis of ascending and descending LOS displacements, R = 9000 m. (<b>e</b>,<b>f</b>) Joint EOF analysis of approximate upward and eastward displacements, R = 15,000 m. (<b>g</b>,<b>h</b>) Joint EOF analysis of approximate upward and eastward displacements, R = 9000 m. Green-framed insets in (<b>b</b>,<b>d</b>,<b>f</b>,<b>h</b>) zoom out the y-axis to show the lack of significance for modes higher than 2.</p>
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<p>Maps of the second mode EOF coefficients. The EOF analysis of the 1992–2010 displacement time series was carried out inside a circular area, 9000 m in radius, centred on the magenta star in <a href="#remotesensing-15-03038-f007" class="html-fig">Figure 7</a>, in order to exclude the “girdle” of discontinuous strong subsidence approximately 10 km from the Vesuvio summit. (<b>a</b>) EOF coefficients for the ascending-orbit LOS displacements, obtained from the joint EOF analysis of ascending and descending LOS displacements; (<b>b</b>) EOF coefficients for the descending-orbit LOS displacements, obtained from the joint EOF analysis of ascending and descending LOS displacements; (<b>c</b>) EOF coefficients for the approximate upward displacements, obtained from the joint EOF analysis of approximate upward and eastward LOS displacements; (<b>d</b>) EOF coefficients for the approximate eastward displacements, obtained from the joint EOF analysis of approximate upward and eastward LOS displacements. (<b>e</b>,<b>f</b>) Computed ascending- and descending-orbit LOS displacements caused by the depressurisation of a very small (point) spheroidal cavity embedded in a homogeneous elastic half-space whose Poisson’s ratio is 0.25; source depth is 7300 m; polar-to-equatorial radius is 1.1; the magenta square gives the source position.</p>
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<p>Mean ground LOS velocities from pre-2001 and post-2002 SAR data. Each velocity component is referenced to its median value inside the area enclosed by the red polygon. (<b>a</b>,<b>c</b>) Pre-2001 velocity. (<b>b</b>,<b>d</b>) Post-2002 velocity. (<b>a</b>,<b>b</b>) Ascending orbit. (<b>c</b>,<b>d</b>) Descending orbit.</p>
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<p>Approximate mean upward and eastward ground velocities from pre-2001 and post-2002 SAR data. Each velocity component is referenced to its median value inside the area enclosed by the red polygon. (<b>a</b>,<b>c</b>) Pre-2001 velocity. (<b>b</b>,<b>d</b>) Post-2002 velocity. (<b>a</b>,<b>b</b>) Approximate upward displacement. (<b>c</b>,<b>d</b>) Approximate eastward displacement. Green arrows in (<b>b</b>,<b>d</b>) give post-2002 upward and horizontal cGPS velocities, respectively, with respect to six stations located outside the Neapolitan volcanic area [<a href="#B11-remotesensing-15-03038" class="html-bibr">11</a>]; TERZ velocity seems somewhat anomalous.</p>
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<p>Difference between post-2002 and pre-2001 mean velocities. Each velocity component is referenced to its median value inside the area enclosed by the red polygon. (<b>a</b>) Ascending orbit, LOS direction. (<b>b</b>) Descending orbit, LOS direction. (<b>c</b>) Approximate upward displacement. (<b>d</b>) Approximate eastward displacement.</p>
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11 pages, 3449 KiB  
Article
Independent Risk Factors of Postoperative Coronal Imbalance after Adult Spinal Deformity Surgery
by Alberto Ruffilli, Francesca Barile, Azzurra Paolucci, Marco Manzetti, Giovanni Viroli, Marco Ialuna, Fabio Vita, Tosca Cerasoli and Cesare Faldini
J. Clin. Med. 2023, 12(10), 3559; https://doi.org/10.3390/jcm12103559 - 19 May 2023
Cited by 1 | Viewed by 3165
Abstract
The aim of the present study is to elucidate preoperative risk factors for inadequate correction of coronal imbalance and/or creation of new postoperative coronal imbalance (iatrogenic CIB) in patients who undergo surgery for Adult Spinal Deformity (ASD). A retrospective review of adults who [...] Read more.
The aim of the present study is to elucidate preoperative risk factors for inadequate correction of coronal imbalance and/or creation of new postoperative coronal imbalance (iatrogenic CIB) in patients who undergo surgery for Adult Spinal Deformity (ASD). A retrospective review of adults who underwent posterior spinal fusion (>5 levels) for ASD was performed. Patients were divided into groups according to the Nanjing classification: type A (CSVL < 3 cm), type B (CSVL > 3 cm and C7 plumb line shifted to major curve concavity), and type C (CSVL > 3 cm and C7 plumb line shifted to major curve convexity). They were also divided according to postoperative coronal balance in balanced (CB) vs. imbalanced (CIB) and according to iatrogenic coronal imbalance (iCIB). Preoperative, postoperative, and last follow-up radiographical parameters and intraoperative data were recorded. A multivariate analysis was performed to identify independent risk factors for CIB. A total of 127 patients were included (85 type A, 30 type B, 12 type C). They all underwent long (average levels fused 13.3 ± 2.7) all-posterior fusion. Type C patients were more at risk of developing postoperative CIB (p = 0.04). Multivariate regression analysis indicated L5 tilt angle as a preoperative risk factor for CIB (p = 0.007) and indicated L5 tilt angle and age as a preoperative independent risk factors for iatrogenic CIB (p = 0.01 and p = 0.008). Patients with a preoperative trunk shift towards the convexity of the main curve (type C) are more prone to postoperative CIB and leveling the L4 and L5 vertebrae is the key to achieve coronal alignment preventing the “takeoff phenomenon”. Full article
(This article belongs to the Special Issue Spinal Disorders: Current Treatment and Future Opportunities: Part II)
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<p>A case classified A both preoperative and postoperative. Red line: C7 plumb line; Blue line: central sacral vertical line.</p>
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<p>A case classified B preoperative and A postoperative. Red line: C7 plumb line; Blue line: central sacral vertical line.</p>
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<p>A case classified C both in preoperative and postoperative. Red line: C7 plumb line; Blue line: central sacral vertical line.</p>
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27 pages, 11909 KiB  
Article
Pearson K-Mean Multi-Head Attention Model for Deformation Prediction of Super-High Dams in First Impoundments
by Yilun Wei, Chang Liu, Hang Duan, Yajun Wang, Yu Hu, Xuezhou Zhu, Yaosheng Tan and Lei Pei
Water 2023, 15(9), 1734; https://doi.org/10.3390/w15091734 - 30 Apr 2023
Cited by 2 | Viewed by 1617
Abstract
The first impoundment of a super-high dam is a crucial period from dam construction to operation, in which the prediction of the dam deformation is vital for the continued safety of the dam. Therefore, a multi-head attention model based on Pearson K-means clustering [...] Read more.
The first impoundment of a super-high dam is a crucial period from dam construction to operation, in which the prediction of the dam deformation is vital for the continued safety of the dam. Therefore, a multi-head attention model based on Pearson K-means clustering is proposed, which is shortened to PKMA. The inputs of the PKMA include measurements of the displacements of plumb lines, water levels, air temperatures, dam body temperatures, water temperatures, and foundation temperatures. Among these inputs, variables related to displacements are regarded as the dominant explanatory factors. Hence, the K-means clustering based on the Pearson index is utilised to increase the weights of displacements in the PKMA. To involve the interactions between inputs, the MA mechanism of neural networks is used to simulate the relationship between inputs and deformation targets. The PKMA model had a maximum MSE of 1.2518 and a maximum MAE of 0.9017 for the model performance metrics at the study measurement points. Compared to the comparison models MA, HST, and LSTM, the performance metrics of the PKMA model are an improvement of an average of 87.02%, 72.42%, and 69.24%. Full article
(This article belongs to the Section Hydraulics and Hydrodynamics)
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<p>Process of establishing the PKMA model.</p>
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<p>Multi-head self-attention mechanism.</p>
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<p>Self-attention layer.</p>
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<p>Layout of normal plumb lines of Baihetan dam.</p>
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<p>Baihetan normal plumb line first impoundment time course curve. (Different colours represent the temporal process lines of deformation monitoring data at different measurement points).</p>
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<p>Thermometer arrangement of dam body.</p>
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<p>Thermometer arrangement of foundation.</p>
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<p>Temperatures of the dam body. (<b>a</b>) Measurements on 1 April 2021; (<b>b</b>) Measurements on 30 June 2021; (<b>c</b>) Measurements on 31 October 2021.</p>
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<p>Temperatures of the dam body. (<b>a</b>) Measurements on 1 April 2021; (<b>b</b>) Measurements on 30 June 2021; (<b>c</b>) Measurements on 31 October 2021.</p>
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<p>Temperatures of the foundation. (<b>a</b>) Measurements on 1 April 2021; (<b>b</b>) Measurements on 30 June 2021; (<b>c</b>) Measurements on 31 October 2021.</p>
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<p>Temperatures of the foundation. (<b>a</b>) Measurements on 1 April 2021; (<b>b</b>) Measurements on 30 June 2021; (<b>c</b>) Measurements on 31 October 2021.</p>
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<p>Upstream water level time series process line.</p>
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<p>Displacement clustering. (<b>a</b>) clustering Pearson index similarity, (<b>b</b>) clustering partition map, different colored boxes represent different clusters.</p>
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<p>Joint grouting zones of the Baihetan dam.</p>
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<p>Degree of model improvement.</p>
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<p>Selected foundation temperatures for PKMA models.</p>
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<p>Converging curve of the PKMA on Baihetan data. (<b>a</b>) Curve of PLdb7-4; (<b>b</b>) Curve of PLdb18-4; (<b>c</b>) The curve of PLdb28-3.</p>
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<p>Converging curve of the PKMA on Baihetan data. (<b>a</b>) Curve of PLdb7-4; (<b>b</b>) Curve of PLdb18-4; (<b>c</b>) The curve of PLdb28-3.</p>
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<p>Performance of the PKMA models. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Performance of the PKMA models. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Average colourations of inputs of the PKMA. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Average colourations of inputs of the PKMA. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Prediction comparisons from different models. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Prediction comparisons from different models. (<b>a</b>) Results of PLdb7-4; (<b>b</b>) Results of PLdb18-4; (<b>c</b>) Results of PLdb28-3.</p>
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<p>Locations of two groups of study targets. (<b>a</b>) Baihetan dam; (<b>b</b>) Xiluodu dam.</p>
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<p>Comparisons between pretraining and non-pretraining. (<b>a</b>) Pretraining results; (<b>b</b>) Non-pretraining results; (<b>c</b>) Pretraining results; (<b>d</b>) Non-pretraining results; (<b>e</b>) Pretraining results; (<b>f</b>) Non-pretraining results.</p>
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<p>Comparisons of the PKMA model performances. (<b>a</b>) Results of PLdb5-4; (<b>b</b>) Results of PLdb15-4; (<b>c</b>) Results of PLdb27-3.</p>
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<p>Comparisons of the PKMA model performances. (<b>a</b>) Results of PLdb5-4; (<b>b</b>) Results of PLdb15-4; (<b>c</b>) Results of PLdb27-3.</p>
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15 pages, 3295 KiB  
Article
Non-Intrusive Voltage-Inversion Measurement Method for Overhead Transmission Lines Based on Near-End Electric-Field Integration
by Wei Liao, Qing Yang, Kun Ke, Zhenhui Qiu, Yuqing Lei and Fei Jiao
Energies 2023, 16(8), 3415; https://doi.org/10.3390/en16083415 - 13 Apr 2023
Cited by 3 | Viewed by 1422
Abstract
Existing electric-field integral inversion methods have limited field application conditions, and they are difficult to arrange electric-field measurement points on high-span overhead lines. This paper proposes a non-intrusive voltage measurement method for overhead transmission lines based on the near-end electric-field integration method. First, [...] Read more.
Existing electric-field integral inversion methods have limited field application conditions, and they are difficult to arrange electric-field measurement points on high-span overhead lines. This paper proposes a non-intrusive voltage measurement method for overhead transmission lines based on the near-end electric-field integration method. First, the electric-field distribution under 10 kV lines is calculated by finite element simulation software. The electric-field distribution of the plumb line and the discrete integral node below the wire are analyzed. Then, based on traditional electric-field integration, a line-voltage-inversion measurement method based on near-end electric-field integration is proposed. In addition, a voltage-monitoring system based on near-end electric-field integration is constructed. Next, the numerical integration types, the number of integration nodes, and the scale coefficient of the near-end region of the inversion algorithm are optimized with the electric-field simulation data. Finally, to verify the voltage-inversion method proposed in this paper, a test platform for overhead-line voltage is constructed using a MEMS electric-field sensor. The results indicate that the voltage-inversion error is 5.75%. The research results will provide theoretical guidance for non-intrusive voltage-inversion measurement of overhead lines. Full article
(This article belongs to the Topic High Voltage Systems and Smart Technologies)
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<p>The voltage measurement model for overhead transmission lines based on the electric-field integration method.</p>
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<p>The cross-sectional view of the mesh division.</p>
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<p>The electric-field distribution below the A-phase wire.</p>
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<p>The electric-field variation curves of the integration nodes at different positions below the A-phase conductor of the 10 kV line.</p>
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<p>The flow chart of the line-voltage inversion algorithm.</p>
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<p>The overhead-line-voltage monitoring system based on the near-end electric-field integration method.</p>
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<p>The MEMS electric-field sensor and the internal MEMS-chip microstructure.</p>
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<p>The influence law of the near-end integral region coefficient on the maximum relative error of the inversion voltage.</p>
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<p>The results of three-point Gaussian–Chebyshev proximal integral inversion at k = 0.9.</p>
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<p>The non-intrusive voltage-measurement test platform for overhead lines.</p>
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<p>The electric-field waveform of three integral nodes measured by the MEMS electric-field sensor.</p>
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<p>The inversion calculation of the line-voltage waveform and the actual voltage comparison.</p>
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11 pages, 2224 KiB  
Article
Postural Evaluation in Young Healthy Adults through a Digital and Reproducible Method
by Bruno Trovato, Federico Roggio, Martina Sortino, Marta Zanghì, Luca Petrigna, Rosario Giuffrida and Giuseppe Musumeci
J. Funct. Morphol. Kinesiol. 2022, 7(4), 98; https://doi.org/10.3390/jfmk7040098 - 28 Oct 2022
Cited by 12 | Viewed by 7782
Abstract
Different tools for the assessment of posture exist, from the simplest and cheap plumb line to complex, expensive, 3D-marker-based systems. The aim of this study is to present digital postural normative data of young adults collected through a mobile app to expand the [...] Read more.
Different tools for the assessment of posture exist, from the simplest and cheap plumb line to complex, expensive, 3D-marker-based systems. The aim of this study is to present digital postural normative data of young adults collected through a mobile app to expand the possibilities of digital postural evaluation. A sample of 100 healthy volunteers, 50 males and 50 females, was analyzed with the mobile app Apecs-AI Posture Evaluation and Correction System® (Apecs). The Student’s t-test evaluated differences between gender to highlight if the digital posture evaluation may differ between groups. A significant difference was present in the anterior coronal plane for axillary alignment (p = 0.04), trunk inclination (p = 0.03), and knee alignment (p = 0.01). Head inclination (p = 0.04), tibia shift (p = 0.01), and foot angle (p < 0.001) presented significant differences in the sagittal plane, while there were no significant differences in the posterior coronal plane. The intraclass correlation coefficient (ICC) was considered to evaluate reproducibility. Thirteen parameters out of twenty-two provided an ICC > 0.90, three provided an ICC > 0.60, and six variables did not meet the cut-off criteria. The results highlight that digital posture analysis of healthy individuals may present slight differences related to gender. Additionally, the mobile app showed good reproducibility according to ICC. Digital postural assessment with Apecs could represent a quick method for preventing screening in the general population. Therefore, clinicians should consider this app’s worth as an auxiliary posture evaluation tool. Full article
(This article belongs to the Special Issue 3D Analysis of Human Movement, Sport, and Health Promotion)
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<p>Landmarks positioning.</p>
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<p>Evaluation of the anterior coronal plane (<b>A</b>); of the sagittal plane (<b>B</b>); of the posterior coronal plane (<b>C</b>).</p>
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<p>Box plots of the differences between male and female groups in the anterior coronal plane with indication of significance. Figure (<b>A</b>) is for body alignment; figure (<b>B</b>) is for head alignment, figure (<b>C</b>) is of acromion alignment, figure (<b>D</b>) is for axillae alignment, figure (<b>E</b>) is for trunk inclination, figure (<b>F</b>) is for ribcage tilt, figure (<b>G</b>) is for antero superior iliac spine inclination, figure (<b>H</b>) is for knee angle. *: <span class="html-italic">p</span> &lt; 0.05; ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Box plots of the differences between male and female groups in the posterior coronal plane. Figure (<b>A</b>) is for body alignment; figure (<b>B</b>) is for head alignment, figure (<b>C</b>) is of shoulder alignment, figure (<b>D</b>) is for axillae alignment, figure (<b>E</b>) is for scapulae alignment, figure (<b>F</b>) is for trunk inclination, figure (<b>G</b>) is for postero superior iliac spine inclination, figure (<b>H</b>) is for knee angle, figure (<b>I</b>) is for foot angle.</p>
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<p>Box plots of the postural differences between male and female groups in the sagittal plane with indication of significance. Figure (<b>A</b>) is for body alignment; figure (<b>B</b>) is for head alignment, figure (<b>C</b>) is of acromion alignment, figure (<b>D</b>) is pelvic tilt, figure (<b>E</b>) is for tibia shift, figure (<b>F</b>) is for fibula alignment, figure (<b>G</b>) is for foot angle. *: <span class="html-italic">p</span> &lt; 0.05; **: <span class="html-italic">p</span> &lt; 0.01; ***: <span class="html-italic">p</span> &lt; 0.001.</p>
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15 pages, 3030 KiB  
Article
A Novel All-Weather Method to Determine Deflection of the Vertical by Combining 3D Laser Tracking Free-Fall and Multi-GNSS Baselines
by Xin Jin, Xin Liu, Jinyun Guo, Maosheng Zhou and Kezhi Wu
Remote Sens. 2022, 14(17), 4156; https://doi.org/10.3390/rs14174156 - 24 Aug 2022
Viewed by 1519
Abstract
The bright stars in the clear night sky with weak background lights should be observed in the traditional deflection of the vertical (DOV) measurement so that the DOV cannot be observed under all-weather conditions, which limits its wide applications. An all-weather DOV measurement [...] Read more.
The bright stars in the clear night sky with weak background lights should be observed in the traditional deflection of the vertical (DOV) measurement so that the DOV cannot be observed under all-weather conditions, which limits its wide applications. An all-weather DOV measurement method combining three-dimensional (3D) laser tracking free-fall and multi-GNSS baselines is proposed in this paper. In a vacuum environment, the 3D laser tracking technique is used to continuously track and observe the motion of free-fall with high frequency and precision for obtaining 3D coordinate series. The plumb line vector equation is established to solve the gravity direction vector in the coordinate system of the laser tracker at the measuring point using least squares fitting coordinate series. Multi-GNSS observations are solved for obtaining the precise geodetic cartesian coordinates of the measuring point and GNSS baseline information. A direction transformation method based on the baseline information proposed in this paper is used to convert the gravitational direction vector in the laser tracker coordinate system into the geodetic cartesian coordinate system. The geodetic cartesian coordinates of the measuring point are used to calculate the ellipsoid normal vector, and the angle between this and the gravity direction vector in the geodetic cartesian coordinate system is estimated to obtain the astrogeodetic DOV. The DOV is projected to the meridian and prime vertical planes to obtain the meridian and prime vertical components of the DOV, respectively. The astronomical latitude and longitude of the measuring point are calculated from these two components. The simulation experiments were carried out using the proposed method, and it was found that the theoretical precision of the DOV measured by the method could reach 0.2″, which could realise all-weather observation. Full article
(This article belongs to the Special Issue Remote Sensing in Space Geodesy and Cartography Methods)
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<p>Sketch of DOV measurement. 1: Base, 2: measuring cylinder, 3: laser tracker, 4: GNSS antenna, 5: free-fall target.</p>
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<p>Technical route of DOV measurement.</p>
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<p>Flowchart of the TLS iterative method.</p>
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<p>Comparison of gravity direction vectors of LS and TLS.</p>
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<p>Distribution of DOV in different radius <b>r</b> (″).</p>
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<p>Influence distribution of laser tracking error on DOV in different radius <b>r</b> (″).</p>
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<p>Influence distribution of GNSS error on DOV in different radius <b>r</b> (″).</p>
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8 pages, 249 KiB  
Article
Relationship between Lower Limbs Performance and Spinal Alignment in Parkinson’s Disease Patients: An Observational Study with Cross Sectional Design
by Luciano Bissolotti, Matteo Rota, Stefano Calza, Eleuterio A. Sanchez Romero, Andrea Battaglino and Jorge H. Villafañe
J. Clin. Med. 2022, 11(13), 3775; https://doi.org/10.3390/jcm11133775 - 29 Jun 2022
Cited by 7 | Viewed by 2089
Abstract
Parkinson’s disease (PD) is a progressive neurodegenerative disease determining spinal deformities and muscle rigidity, weakness and dystonia that can be related to a change in muscular output during sit-to-stand tasks (STS). Purpose: The aim of this study was to determine the impacts of [...] Read more.
Parkinson’s disease (PD) is a progressive neurodegenerative disease determining spinal deformities and muscle rigidity, weakness and dystonia that can be related to a change in muscular output during sit-to-stand tasks (STS). Purpose: The aim of this study was to determine the impacts of spinal alignment on lower limbs performance during STS tasks in Parkinson’s disease (PD) patients and healthy controls. Methods: In total, 43 consecutive PD patients (“PD” Group, 25 males and 18 females; age 73.7 ± 7.1) and 42 people not affected by any type of neurological disease (“CON” Group, 22 males, 20 females; age 69.8 ± 6.0) participated in the observational study. The clinical assessment included: IPAQ (International Physical Activity Questionnaire), Hoehn Yahr score, plumb-line distance from the spinous process of C7, kyphosis apex and the spinous process of L3 and S1. We used the Muscle Quality Index test (MQI) to assess muscle power output during STS in both groups. Results: The MQI test measurements of absolute and relative lower limb power was significantly lower in the PD group, in addition to a negative correlation with age and a positive correlation with PL-L3 in that group of patients. Conclusions: A final consideration regarding our results leads to the possibility that the preservation of lumbar lordosis may be one of the factors for maintaining efficient biomechanics of the lower limb muscles, with the preservation of the physiological contractile characteristics of these muscles being the objective for a multidisciplinary rehabilitation based on postural exercises of the spine and a program of training exercises for the lower limb muscles. Full article
14 pages, 1394 KiB  
Article
Osteopathic Treatment and Evaluation in the Clinical Setting of Childhood Hematological Malignancies
by Monica Barbieri, William Zardo, Chiara Frittoli, Clara Rivolta, Valeria Valdata, Federico Bouquin, Greta Passignani, Alberto Maggiani, Momcilo Jankovic, Andrea Cossio, Andrea Biondi, Adriana Balduzzi and Francesca Lanfranconi
Cancers 2021, 13(24), 6321; https://doi.org/10.3390/cancers13246321 - 16 Dec 2021
Cited by 1 | Viewed by 3545
Abstract
Children: adolescents, and young who are adults affected with hematological malignancies (CAYA-H) and who are undergoing intensive phases of cancer treatment, including hematopoietic stem cell transplantation (HSCT), experience diminished functional ability. This study was aimed at assessing the feasibility, efficacy, safety, and satisfaction [...] Read more.
Children: adolescents, and young who are adults affected with hematological malignancies (CAYA-H) and who are undergoing intensive phases of cancer treatment, including hematopoietic stem cell transplantation (HSCT), experience diminished functional ability. This study was aimed at assessing the feasibility, efficacy, safety, and satisfaction of an osteopathic intervention in CAYA-H attending an 11-week precision-based exercise program (PEx). All of the participants were given 4–10 treatments according to the prescription ordered by the sports medicine doctor in charge of the PEx, and the following outcomes were assessed: (1) spinal column range of motion (ROM) by palpation; (2) lower and upper limb joints ROM by a goniometer; (3) orthostatic posture by plumb line assessment; (4) chest and abdomen mobility by inspection and palpation; (5) cranial-sacral rhythmic impulse (CRI) by palpation; and (6) adverse effects. Goal attainment scaling (GAS) was used to identify the accomplishment of a desired clinical result. Moreover, HSCT patients who were affected with graft-versus-host disease and/or osteonecrosis had their joints assessed in terms of ROM as tools to monitor the effectiveness of immunosuppressive treatment. A total of 231 CAYA-H were identified, and 104 participated in the study (age 10.66 ± 4.51 yrs; 43% F). PEx plus osteopathy reached positive GAS scores by improving the ROMs of the spinal column and/or limbs (81% and 78%, respectively), chest and abdomen mobility (82%), and CRI (76%). Only minor reversible adverse effects were noticed during the study. Together, our data seem to initiate a new course where osteopathy could be useful in evaluating structural edges due to the clinical history of each CAYA-H. Given the contributions that were obtained by the GAS scores, osteopathic treatment seems to reveal interesting potential that can be targeted in the future. Full article
(This article belongs to the Special Issue Pediatric/Adolescent Cancer and Exercise)
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<p>The violin plot graph shows the goal attainment scaling (GAS) scores of the spinal column mobility divided into sacral, pelvic, lumbar, dorsal, and cervical districts after 11 weeks of precision-based exercise plus osteopathic treatment. Only children, adolescents, and young adults with medium or high adherence to the training sessions and osteopathic treatments were considered (see the method section for further details). EXT, extension; SB, side bending, NOD, nodding.</p>
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<p>The violin plot graph shows the goal attainment scaling (GAS) score for the range of motion in the lower limbs, divided in hip, knee, and ankle districts after 11 weeks of precision-based exercise plus osteopathic treatment. Only children, adolescents, and young adults with medium or high adherence to the training sessions and osteopathic treatments were considered (see the method section for further details). ER and IR, external and internal rotation; EXT extension; FLE, flexion.</p>
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<p>(<b>A</b>,<b>B</b>) The violin plot graph shows the goal attainment scaling (GAS) scores of the cranial and sacral impulse (CRI) districts. Only children, adolescents, and young adults with medium or high adherence to the training sessions and osteopathic treatments were considered (see the method section for further details). R, rhythm; A, amplitude; S, strength.</p>
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16 pages, 3311 KiB  
Article
Chemical, Cytotoxic, and Anti-Inflammatory Assessment of Honey Bee Venom from Apis mellifera intermissa
by Iouraouine El Mehdi, Soraia I. Falcão, Mustapha Harandou, Saïd Boujraf, Ricardo C. Calhelha, Isabel C. F. R. Ferreira, Ofélia Anjos, Maria G. Campos and Miguel Vilas-Boas
Antibiotics 2021, 10(12), 1514; https://doi.org/10.3390/antibiotics10121514 - 10 Dec 2021
Cited by 8 | Viewed by 3880
Abstract
The venom from Apis mellifera intermissa, the main honey bee prevailing in Morocco, has been scarcely studied, despite its known potential for pharmacological applications. In the present work, we investigated the composition, the anti-inflammatory activity, and the venom’s cytotoxic properties from fifteen [...] Read more.
The venom from Apis mellifera intermissa, the main honey bee prevailing in Morocco, has been scarcely studied, despite its known potential for pharmacological applications. In the present work, we investigated the composition, the anti-inflammatory activity, and the venom’s cytotoxic properties from fifteen honey bee venom (HBV) samples collected in three regions: northeast, central, and southern Morocco. The chemical assessment of honey bee venom was performed using LC-DAD/ESI/MSn, NIR spectroscopy and AAS spectroscopy. The antiproliferative effect was evaluated using human tumor cell lines, including breast adenocarcinoma, non-small cell lung carcinoma, cervical carcinoma, hepatocellular carcinoma, and malignant melanoma. Likewise, we assessed the anti-inflammatory activity using the murine macrophage cell line. The study provides information on the honey bee venom subspecies’ main components, such as melittin, apamin, and phospholipase A2, with compositional variation depending on the region of collection. Contents of toxic elements such as cadmium, chromium, and plumb were detected at a concentration below 5 ppm, which can be regarded as safe for pharmaceutical use. The data presented contribute to the first study in HBV from Apis mellifera intermissa and highlight the remarkable antiproliferative and anti-inflammatory effects of HBV, suggesting it to be a candidate natural medicine to explore. Full article
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<p>(<b>a</b>) <span class="html-italic">Apis mellifera intermissa</span>; (<b>b</b>) Map of Morocco with the site of collection: <span class="html-fig-inline" id="antibiotics-10-01514-i001"> <img alt="Antibiotics 10 01514 i001" src="/antibiotics/antibiotics-10-01514/article_deploy/html/images/antibiotics-10-01514-i001.png"/></span> northeast, <span class="html-fig-inline" id="antibiotics-10-01514-i002"> <img alt="Antibiotics 10 01514 i002" src="/antibiotics/antibiotics-10-01514/article_deploy/html/images/antibiotics-10-01514-i002.png"/></span> center and <span class="html-fig-inline" id="antibiotics-10-01514-i003"> <img alt="Antibiotics 10 01514 i003" src="/antibiotics/antibiotics-10-01514/article_deploy/html/images/antibiotics-10-01514-i003.png"/></span> southern samples.</p>
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<p>(<b>a</b>) Representative chromatographic profile at 220 nm of <span class="html-italic">A. mellifera intermissa</span> venom (1-apamin; 2-phospholipase A2; IS-internal standard: cytochrome c at 25 µg/mL; 3-melittin); (<b>b</b>) Full scan mass spectrum of apamin (tr = 4.78 min; MW = 2032 Da); (<b>c</b>) Full scan mass spectrum of melittin (tr = 9.80 min; MW = 2846 Da).</p>
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<p>Normalized NIR spectra for HBV, with the indication of the most relevant bands.</p>
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<p>PCA score plot of the more relevant spectral region of NIR spectra of <span class="html-italic">A. mellifera intermissa</span> venom from the three regions of Morocco (<b>A1</b>) and excluding sample NE5 (<b>B1</b>). (<b>A2</b>,<b>B2</b>) displayed the second derivative pretreatment.</p>
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<p>Cytotoxicity activity of <span class="html-italic">A. mellifera intermissa</span> venom from the three regions (S, South; C, Center; NE, Northeast Morocco). The results are expressed in GI<sub>50</sub> values (µg/mL), corresponding to the concentration causing 50% growth inhibition in the five human tumor lines or porcine liver primary culture PLP2.</p>
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12 pages, 2050 KiB  
Article
Effects of Total Knee Arthroplasty on Coronal and Sagittal Whole-Body Alignments: Serial Assessments Using Whole-Body EOS
by Seong-Chan Kim, Han-Gyeol Choi, Joo-Sung Kim, Tae-Woo Kim and Yong-Seuk Lee
J. Clin. Med. 2021, 10(15), 3242; https://doi.org/10.3390/jcm10153242 - 23 Jul 2021
Cited by 4 | Viewed by 2946
Abstract
Background: The aims of this study were to evaluate the effects of correcting lower limb alignment by total knee arthroplasty (TKA) on the spinopelvic alignment and to identify patients with difference in the knee joint between clinically measured passive motion and the actual [...] Read more.
Background: The aims of this study were to evaluate the effects of correcting lower limb alignment by total knee arthroplasty (TKA) on the spinopelvic alignment and to identify patients with difference in the knee joint between clinically measured passive motion and the actual standing posture. Methods: In this retrospective study, 101 patients who underwent TKA and whose serial whole-body EOS X-ray were available were included. The relationship of the knee and spinopelvic alignment was analyzed by evaluating the parameters of standing anterior-posterior and lateral whole-body EOS X-ray. The differences between postoperative passive motion and weight-bearing posture in the knee joint were assessed in both coronal and sagittal planes. Furthermore, the causes of such differences were analyzed. Results: Significant correlations between Δpelvic obliquity and coronal ΔHip-Knee-Ankle (HKA)Rt-Lt angle between the preoperative and 3-month and 1-year postoperative data (p < 0.001 and p < 0.005, respectively) and improved with coronal lower limb alignment close to neutral resulted in decreased pelvic obliquity (p < 0.001, ß = 0.085 and p = 0.005, ß = 0.065, respectively) were observed. The correlations between Δpelvic tilt (PT) and Δsacral slope (SS) and sagittal ΔHKARt-Lt angle were statistically significant (PT: p < 0.001 and p < 0.045; SS: p = 0.002 and p < 0.001, respectively). The improved sagittal alignment close to neutral resulted in decreased PT and increased SS. The difference between postoperative passive motion and the weight-bearing posture of the knee joint was correlated with lumbar lordosis and sagittal C7 plumb line-sacrum distance (p = 0.042 and p < 0.001, respectively). Conclusions: The correction of lower limb alignment with TKA affected pelvic parameters dominantly; however, there was little effect on the spinal alignment. Additionally, patients with anterior stooping or lumbar flat back demonstrated difference in extension between passive knee motion and standing. Therefore, rather than only focusing on changes in the knee alignment correction, knee surgeons should also evaluate the spinopelvic alignment before surgery to consider the prognosis of the standing and predict the possible changes in the whole-body alignment. This preoperative assessment may improve the prognosis of TKA. Full article
(This article belongs to the Special Issue Diagnosis and Management of Knee Injuries)
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<p>(<b>A</b>) Measurement of coronal HKA angle: coronal HKA<sub>Rt-Lt</sub> = −8.23°; (<b>B</b>) measurement of pelvic obliquity: −1.67°; (<b>C</b>) measurement of the scoliosis angle: +21.18°; (<b>D</b>) measurement of coronal SVA: +16.25 mm.</p>
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<p>(<b>A</b>) Measurement of sagittal HKA angle: +11.03°; (<b>B</b>) measurement of PT: +16.70°; (<b>C</b>) measurement of SS: +43.13°; (<b>D</b>) measurement of TK and LL: +37.01° and +55.09°, respectively; (<b>E</b>) measurement of sagittal SVA: +28.50 mm.</p>
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<p>Corrected closed to neutral knee alignment affected the coronal pelvic obliquity. (<b>A</b>) Measurement of the preoperative coronal HKA angle: coronal HKA<sub>Rt-Lt</sub> = −14.18° and pelvic obliquity: −7.73°; (<b>B</b>) measurement of the postoperative coronal HKA angle: coronal HKA<sub>Rt-Lt</sub> = −1.06° and pelvic obliquity: −3.90°.</p>
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<p>Corrected closed to neutral knee alignment decreased PT and increased SS. (<b>A</b>) Measurement of the preoperative sagittal HKA angle: sagittal HKA<sub>Rt-Lt</sub> = +22.12° and preoperative PT: +54.24° and SS: +10.57°; (<b>B</b>) measurement of the postoperative sagittal HKA<sub>Rt-Lt</sub> = +5.89° and PT: +44.30° and SS: +22.40°.</p>
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<p>The difference between passive motion and weight-bearing of knee joint predominantly appeared if lumbar lordosis decreased or sagittal C7 plumb line was anteriorly located. (<b>A</b>) patient with anterior stooping because of anteriorly located C7 plumb line; (<b>B</b>) patient with decreased lumbar lordosis; (<b>C</b>) patient with combined anterior stooping and decreased lumbar lordosis.</p>
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11 pages, 1905 KiB  
Article
Spinal Flexibility Is an Important Factor for Improvement in Spinal and Knee Alignment after Total Knee Arthroplasty: Evaluation Using a Whole Body EOS System
by Seong Chan Kim, Joo Sung Kim, Han Gyeol Choi, Tae Woo Kim and Yong Seuk Lee
J. Clin. Med. 2020, 9(11), 3498; https://doi.org/10.3390/jcm9113498 - 29 Oct 2020
Cited by 8 | Viewed by 2733
Abstract
The purposes of this study were (1) to evaluate the relationship between lumbosacral flexibility and the effects of total knee arthroplasty (TKA) on whole-body alignment; and (2) to determine the prerequisites of the adjacent joints for successful TKA. A total of 116 patients [...] Read more.
The purposes of this study were (1) to evaluate the relationship between lumbosacral flexibility and the effects of total knee arthroplasty (TKA) on whole-body alignment; and (2) to determine the prerequisites of the adjacent joints for successful TKA. A total of 116 patients (156 cases) who had whole-body X-ray and flexion-extension lumbar radiograph available were enrolled. For the sagittal alignment evaluation, hip–knee–ankle (HKA) angle, pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), and C7 plumb line-sacrum distance (SVA) were evaluated on the whole-body radiographs. Lumbar flexibility (LF) was evaluated using the flexion-extension lumbar radiographs, and pelvic flexibility (PF) was evaluated using the pelvic incidence (PI). The disparities in the knee joint between postoperative passive motion and weight-bearing posture were assessed. LF was significantly correlated with ΔLL and ΔSVA (LL: p = 0.039, SVA: p = 0.040; Pearson correlation coefficient (PCC): −0.206 and 0.205, respectively). There were correlations between PF and ΔSS (p < 0.001, PCC: −0.362), and between the disparity and LF (p = 0.005, PCC = −0.275). Linear regression analysis demonstrated that LF was significantly associated with the presence of disparity (p = 0.005, β = −0.205). LF is an important factor for improved spinal and lower limb alignment after TKA. Additionally, reduced LF may result in knee joint disparity between passive extension and standing extension status. Therefore, surgeons should consider spinopelvic alignment, including lower limb alignment preoperatively, to be able to predict possible changes in whole-body alignment following TKA. Full article
(This article belongs to the Special Issue Diagnosis and Management of Knee Injuries)
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<p>(<b>A</b>) Measurement of hip–knee–ankle (HKA) angle: +22.12°. (<b>B</b>) Measurement of PT: +27.02°. (<b>C</b>) Measurement of SS: +41.33°. (<b>D</b>) Measurement of TK and LL: +33.37° and +42.11°, respectively. (<b>E</b>) Measurement of C7 plumb line-sacrum distance: +13.64 mm. The sagittal HKA angle was defined as the angle between two lines: One joining the center of the femoral head and the center of the knee and the other joining the center of the knee and the center of the superiaor articular surface of the talus.</p>
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<p>(<b>A</b>) Measurement of lumbar lordosis (LL) on extension view: 65.09°. (<b>B</b>) Measurement of LL on flexion view: 35.32°. (<b>C</b>) Measurement of pelvic incidence: 47.17°. The yellow line and circle are the measurement about lumbar lordosis and pelvic incidence</p>
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<p>Patient with larger lumbar flexibility (LF) improved sagittal spinal alignment after TKA: Measurement of LF on flexion-extension view: 58.81°. (<b>A</b>) Measurement of LL on flexion view: 14.88°. (<b>B</b>) Measurement of LL on extension view: 73.69°, improved spinal alignment increased LL and decreased line-sacrum distance (SVA). (<b>C</b>) Measurement of the preoperative LL: 47.67° and SVA: 45.87 mm. (<b>D</b>) Measurement of postoperative LL: 66.48° and SVA: 15.73 mm. The yellow line and circle are the measurement about lumbar lordosis, SVA and sagittal HKA.</p>
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<p>Patient with larger pelvic flexibility (PF) improved sagittal pelvic alignment, such as increased SS, after TKA. (<b>A</b>) Measurement of PF: 53.33°. (<b>B</b>) Measurement of preoperative SS: 28.57°. (<b>C</b>) Measurement of postoperative SS: 38.07°. The yellow line and circle are the measurement about pelvic incidence and sacral slope.</p>
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<p>Patients with lesser LF have disparities in the knee joint between passive extension and real standing extension after TKA. (<b>A</b>) Measurement of LL on flexion view: 38.58°. (<b>B</b>) Measurement of LL on extension view: 52.41°. (<b>C</b>) Measurement of disparity is 19.32° with passive full extension. The yellow line and circle are the measurement about lumbar flexibility and sagittal HKA.</p>
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<p>Cervical deformity showed little effect on the lower limb and spinal alignment itself. (<b>A</b>) Preoperative cervical lordosis: 3.35° and HKA angle: 8.63°. (<b>B</b>) Postoperative cervical lordosis: 3.55° and HKA angle: 2.37°. Thoracic deformity showed little effect on the lower limb and spinal alignment itself. (<b>C</b>) Preoperative thoracic kyphosis: 54.14° and HKA angle: 0.73°. (<b>D</b>) Postoperative thoracic kyphosis: 54.57° and HKA angle: 0.76°. The yellow line and circle are the measurement about sagittal HKA and cervical lordosis and thoracic kyphosis.</p>
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