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17 pages, 2137 KiB  
Article
Validation of a Set of Clinical Criteria for the Diagnosis of Secondary Progressive Multiple Sclerosis
by Alin Ciubotaru, Daniel Alexa, Cristina Grosu, Lilia Böckels, Ioana Păvăleanu, Alexandra Maștaleru, Maria Magdalena Leon, Roxana Covali, Emanuel Matei Roman, Cătălina Elena Bistriceanu, Cristina Mihaela Ghiciuc, Doina Azoicăi and Emilian Bogdan Ignat
Brain Sci. 2024, 14(11), 1141; https://doi.org/10.3390/brainsci14111141 (registering DOI) - 14 Nov 2024
Abstract
Background/Objectives: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system characterized by progressive impairment of neuronal transmission due to focal demyelination. The most common form is RRMS (relapsing-remitting multiple sclerosis), which, under the influence of certain factors, can [...] Read more.
Background/Objectives: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system characterized by progressive impairment of neuronal transmission due to focal demyelination. The most common form is RRMS (relapsing-remitting multiple sclerosis), which, under the influence of certain factors, can progress to SPMS (secondary progressive multiple sclerosis). Our study aimed to validate the criteria proposed by a working group of the Romanian Society of Neurology versus the criteria proposed by a group of experts from Spain, Karolinska, and Croatia concerning the progression from RRMS to SPMS. Methods: This was done by gathering epidemiological data (age, gender) and by applying clinical tests such as the 9HPT (9-hole peg test), 25FWT (25-foot walk test), and EDSS (expanded disability status scale) tests and the SDMT test (symbol digit modalities test). The present research is a cohort study that included a number of 120 patients diagnosed with MS according to the McDonald Diagnostic Criteria 2017. The study was carried out between January 2023 and April 2024, including patients hospitalized in the Neurology Clinic of the Clinical Rehabilitation Hospital from Iasi, Romania. The data were collected at baseline (T0) and at a 12-month interval (T1). Results: The statistical analysis was conducted using Kaiser–Meyer–Olkin analysis, which indicated a value of 0.683, thus validating the clinical tests used. The correlation matrix and the linear regression for all the tests showed highly significant statistical results. Furthermore, the ROC curve analysis of the criteria suggested by the working group of the Romanian Society of Neurology demonstrated that the EDSS, 9HPT, and 25FWT are highly sensitive in diagnosing SPMS, an opinion that is shared with the Spanish experts, but not with the Karolinska expert panel. Using the criteria given by the Croatian expert group in the ROC curve analysis showed that only the EDSS was strongly significant for the progression to the SPMS phase. Conclusions: In conclusion, all clinical methods used demonstrated that they are valid and can contribute to identifying patients with an increased risk of progression. The model proposed by the Romanian Society of Neurology working group is similar to other countries’ expert opinions and can be used to detect the risk of disease progression and establish a more tailored therapeutic management of SPMS. Full article
(This article belongs to the Section Neuropharmacology and Neuropathology)
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Figure 1

Figure 1
<p>Regression line regarding the correlation between the EDSS score at T0 and T1.</p>
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<p>Regression line regarding the correlation at T0 and T1 for 9HPT, 25 FWT, and SDMT.</p>
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<p>Regression line regarding the correlation at T0 and T1 for 9HPT, 25 FWT, and SDMT.</p>
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<p>ROC curve in relation to the types of ”events” that define the form of SPMS according to the criteria of the working group of the Romanian Society of Neurology.</p>
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<p>The ROC curve in relation to the types of “events” that define the type of the SPMS according to the criteria of the Spanish “expert” group.</p>
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<p>The ROC curve in relation to the types of ”event” that define the type of SPMS according to the Karolinka expert group criteria.</p>
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<p>The ROC curve in relation to the types of “events” that define the shape of the SPMS according to the criteria of the Croatian expert group.</p>
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28 pages, 682 KiB  
Systematic Review
Prognostic Factors in Patients Undergoing Physiotherapy for Chronic Low Back Pain: A Level I Systematic Review
by Alice Baroncini, Nicola Maffulli, Marco Pilone, Gennaro Pipino, Michael Kurt Memminger, Gaetano Pappalardo and Filippo Migliorini
J. Clin. Med. 2024, 13(22), 6864; https://doi.org/10.3390/jcm13226864 (registering DOI) - 14 Nov 2024
Abstract
Background: Low back pain is common. For patients with mechanic or non-specific chronic LBP (cLBP), the current guidelines suggest conservative, nonpharmacologic treatment as a first-line treatment. Among the available strategies, physiotherapy represents a common option offered to patients presenting with cLBP. The [...] Read more.
Background: Low back pain is common. For patients with mechanic or non-specific chronic LBP (cLBP), the current guidelines suggest conservative, nonpharmacologic treatment as a first-line treatment. Among the available strategies, physiotherapy represents a common option offered to patients presenting with cLBP. The present systematic review investigates the prognostic factors of patients with mechanic or non-specific cLBP undergoing physiotherapy. Methods: In September 2024, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. All the randomised controlled trials (RCTs) which evaluated the efficacy of a physiotherapy programme in patients with LBP were accessed. All studies evaluating non-specific or mechanical LBP were included. Data concerning the following PROMs were collected: the pain scale, Roland Morris Disability Questionnaire (RMQ), and Oswestry Disability Index (ODI). A multiple linear model regression analysis was conducted using the Pearson Product–Moment Correlation Coefficient. Results: Data from 2773 patients were retrieved. The mean length of symptoms before the treatment was 61.2 months. Conclusions: Age and BMI might exert a limited influence on the outcomes of the physiotherapeutic management of cLBP. Pain and disability at baseline might represent important predictors of health-related quality of life at the six-month follow-up. Further studies on a larger population with a longer follow-up are required to validate these results. Full article
(This article belongs to the Special Issue Clinical Advances in Spine Disorders)
17 pages, 2843 KiB  
Article
Effects of Traditional Agroforestry Practices on Cocoa Yields in Côte d’Ivoire
by N’Golo Konaté, Yaya Ouattara, Auguste K. Kouakou and Yao S. S. Barima
Sustainability 2024, 16(22), 9927; https://doi.org/10.3390/su16229927 (registering DOI) - 14 Nov 2024
Abstract
Agroforestry is promoted as a practice at the crossroads of sustainability and productivity objectives; however, many agroforestry programmes have had mixed effects due to a lack of understanding of the compatibility of the species supplied to farmers with cocoa and a failure to [...] Read more.
Agroforestry is promoted as a practice at the crossroads of sustainability and productivity objectives; however, many agroforestry programmes have had mixed effects due to a lack of understanding of the compatibility of the species supplied to farmers with cocoa and a failure to take account of their knowledge in designing the programmes. This paper, therefore, examines the effects of socio-economic and agroforestry factors on cocoa yields in Côte d’Ivoire, West Africa. The data used come from surveys of 150 farmers in three areas of the country: Bonon, Soubré and Biankouma. The choice of these areas was based on an east–west gradient, reflecting the evolution of the cocoa loop. The Bayesian Information Criterion method and multiple linear regression were applied to identify the species and their relationship with yield. The results showed that certain species, such as Citrus sp., Cordia senegalensis, Isoberlinia doka, Morinda lucida, Morus mesozygia and Raphia hookeri increased in yield; on the other hand, Anthonotha manii was found to reduce in yield. Finally, labour and insecticides contributed to yield increases. The statistical analysis can be supplemented with agronomic and ecological analyses to improve species management on cocoa farms. Full article
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Figure 1
<p>Map of the study area.</p>
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<p>Choice of species potentially influencing yield using the BIC.</p>
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<p>Distribution of zones by yield (2018–2022).</p>
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<p>Yield trends in the zones from 2018 to 2022.</p>
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<p>Graphical representations of ecological zones as a function of species according to axes 1 and 2 of the PCA.</p>
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<p>Evolution of yields according to cropping system.</p>
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<p>Verification of normality of cocoa yield data.</p>
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14 pages, 275 KiB  
Article
Assessing Barriers and Difficulties to Healthcare Access Among Syrian Refugees in Jordan: An Observational Study
by Yazid Mohammed Gougazeh, Mahmoud Ola AlHussami, Konstantinos Tsaras, Wafa Hamad Almegewly, Savvato Karavasileiadou and Christos Kleisiaris
Healthcare 2024, 12(22), 2276; https://doi.org/10.3390/healthcare12222276 (registering DOI) - 14 Nov 2024
Abstract
(1) Background: Worldwide, refugees may have some difficulties in accessing healthcare services. However, little is known about the factors that may predict the level of accessibility to the public healthcare system in the host countries. (2) Aim: To examine the level of accessibility [...] Read more.
(1) Background: Worldwide, refugees may have some difficulties in accessing healthcare services. However, little is known about the factors that may predict the level of accessibility to the public healthcare system in the host countries. (2) Aim: To examine the level of accessibility of Syrian refugees to the public healthcare system in Jordan and further to identify the prediction of socioeconomic factors and barriers to healthcare access. (3) Methods: A cross-sectional study was conducted with a convenient sample of 356 Syrian refugees residing outside camps (Irbid, Ajloun, and Jarash). Data were collected using the Access to Healthcare Services Scale instrument (adopted from the Canadian Community Health Survey), which is composed of 2 sections: the general access scale (8 items) and the difficulties scale (20 items). One-way ANOVA test and independent t-test were used to examine epidemiological correlations among variables, whereas a hierarchical linear regression model was used to examine the predictability of socioeconomic factors and barriers to overall access to the public healthcare system by exploring the incremental impact of additional predictors. (4) Results: the mean age of the 356 participants was 35.22 years old, 56.5% were female, 67.4% were married, most of them 46.1% have secondary education, and non-employed 69.9%. Significant associations were observed among participants with different marital status (p < 0.001), educational level (mean 11.85 vs. 19.85, p < 0.001), working status (15.47 vs. 17.93, p < 0.001), family household number (16.42 vs. 17.0, p < 0.001), and health insurance (none: 15.50 vs. governmental 24.50, p < 0.001). Multivariate analysis revealed that the most important factors that may predict the overall access to healthcare services were: family monthly income (beta −0.19, p < 0.001), household family number (beta 0.17, <0.001), health insurance (beta −0.09, p = 0.047), and barriers (beta −0.43, <0.001), even after adjusting for potential confounding effects: sex, age, educational level, and place of residence. (5) Conclusions: Our findings indicate that socioeconomic factors and barriers may considerably predict overall access to public healthcare in Jordan. It is crucially important, therefore, for the Jordanian government and international organizations to create and develop strategic plans and programs that enhance refugees’ access to health services, positively impacting their health and wellness. Full article
9 pages, 445 KiB  
Article
Myopia Progression in School-Age Children During the COVID-19 Pandemic
by Gülce Gökgöz Özışık and Hayati Yilmaz
J. Clin. Med. 2024, 13(22), 6849; https://doi.org/10.3390/jcm13226849 (registering DOI) - 14 Nov 2024
Viewed by 62
Abstract
Objectives: This study aimed to investigate changes in refraction error in myopic school-age children during the COVID-19 pandemic. Methods: The data of 825 myopic children aged 7–18 years were retrospectively screened from the hospital data access system. The cycloplegic prescriptions of the [...] Read more.
Objectives: This study aimed to investigate changes in refraction error in myopic school-age children during the COVID-19 pandemic. Methods: The data of 825 myopic children aged 7–18 years were retrospectively screened from the hospital data access system. The cycloplegic prescriptions of the patients in 2018, 2019, 2020, and 2021 were recorded. The patients were divided into three groups according to their ages: ≤10 years (Group A), 11–14 years (Group B), and ≥15 years (Group C). The mean refraction values and annual progression values were compared between the years and age groups. Results: The mean age of the patients was 13.8 ± 3.17 years. Statistical analysis for the overall sample indicated that the annual myopia progression significantly differed between 2018 and 2021 (−0.42 ± 0.37 and −0.53 ± 0.47, respectively) (p < 0.001), and there was also a significant difference in myopia progression observed in all years in the younger age group (−0.34 ± 0.44 for 2018, −0.50 ± 0.49 for 2019, and −0.76 ± 0.59 for 2020). The highest progression (−0.76 ± 0.59) was determined in the younger age group in 2020. Linear regression analysis showed a negative correlation between myopia progression from 2020 to 2021 and age (B = 0.049 and p < 0.001). Conclusions: Myopia progression has increased in school-age children during COVID-19, with the younger age group being more affected. During the COVID-19 pandemic, myopia progression in younger children has increased statistically significantly. Thus, at times when distance learning is required, it would be appropriate to plan by taking into account the myopia progression of children. Full article
(This article belongs to the Section Ophthalmology)
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Figure 1

Figure 1
<p>This graph illustrates the annual myopia progression from 2018 to 2021 across four age groups: patients aged ≤ 10 (Group A), 11–14 years (Group B), and ≥15 years (Group C), and the total sample. The data show that the youngest group (Group A) experienced a faster progression rate, especially during the 2020–2021 period. The SD (standard deviation) values, shown next to each point, reflect the variability in progression.</p>
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21 pages, 2179 KiB  
Article
Market Predictability Before the Closing Bell Rings
by Lu Zhang and Lei Hua
Risks 2024, 12(11), 180; https://doi.org/10.3390/risks12110180 - 13 Nov 2024
Viewed by 260
Abstract
This study examines the predictability of the last 30 min of intraday stock price movements within the US financial market. The analysis encompasses several potential explanatory variables, including returns from each 30 min intraday trading session, overnight returns, the federal reserve fund rate [...] Read more.
This study examines the predictability of the last 30 min of intraday stock price movements within the US financial market. The analysis encompasses several potential explanatory variables, including returns from each 30 min intraday trading session, overnight returns, the federal reserve fund rate decision days and the subsequent three days, the US dollar index, month effects, weekday effects, and market volatilities. Market-adaptive trading strategies are developed and backtested on the basis of the study’s insights. Unlike the commonly employed multiple linear regression methods with Gaussian errors, this research utilizes a Bayesian linear regression model with Student-t error terms to more accurately capture the heavy tails characteristic of financial returns. A comparative analysis of these two approaches is conducted and the limitations inherent in the traditionally used method are discussed. Our main findings are based on data from 2007 to 2018. We observed that well-studied factors such as overnight effects and intraday momentum have diminished over time. Some other new factors were significant, such as lunchtime returns during boring days and the tug-of-war effect over the days after a federal fund rate change decision. Ultimately, we incorporate findings derived from data spanning 2022 to 2024 to provide a contemporary perspective on the examined components, followed by a discussion of the study’s limitations. Full article
(This article belongs to the Special Issue Modern Statistical and Machine Learning Techniques for Financial Data)
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Figure 1

Figure 1
<p>Definitions of the returns of the 15 trading sessions.</p>
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<p>Conditional effects of intraday and overnight returns, and the shaded areas are <math display="inline"><semantics> <mrow> <mn>95</mn> <mo>%</mo> </mrow> </semantics></math> uncertainty levels. All variables are scaled based on the mean and the standard deviation of the variable over the whole study period to facilitate comparisons among different variables. The slopes of the blue lines suggest the direction and magnitude of the effects of the explanatory variables, and we can observe that the significant variables listed in Panel A of <a href="#risks-12-00180-t003" class="html-table">Table 3</a> show relatively steeper slopes when the same scales are used here for the <math display="inline"><semantics> <msub> <mi>r</mi> <mn>13</mn> </msub> </semantics></math>-axis.</p>
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<p>Conditional effects of FOMC rate decisions and weekdays, and the uncertainty intervals cover <math display="inline"><semantics> <mrow> <mn>95</mn> <mo>%</mo> </mrow> </semantics></math> probability. For the first four plots, “1” indicates the day of interest, and “0” otherwise. All variables are scaled based on the mean and the standard deviation of the variable over the whole study period. Based on the first four plots, we notice that, compared to normal days, the variability of estimates is much higher on those days when the federal fund rate changes were decided and on their consecutive days afterwards. The direction of such effects was not decisive on the decision day, but it appeared to oscillate in the following several days, probably reflecting a tug-of-war effect between the bulls and the bears after critical federal fund rate decisions are made. The last plot suggests a significant “Friday” effect: the returns of the last 30 min were significantly positive on Fridays after controlling for the other variables.</p>
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<p>This figure displays the <math display="inline"><semantics> <mrow> <mn>95</mn> <mo>%</mo> </mrow> </semantics></math> credible intervals of the explanatory variables in the Bayesian linear regression model with Student-<span class="html-italic">t</span> error terms, using a rolling window of 3 years with SPY data. A bar intersecting the red line indicates that the variable is not statistically significant, and significant otherwise. It can be seen from the graphs that the financial market (represented by the S&amp;P 500) is not stationary over different years. An overall result that includes many years of data could be misleading in making conclusions about current market conditions. In the literature, the results of <math display="inline"><semantics> <msub> <mi>r</mi> <mrow> <mn>13</mn> <mi>l</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> </semantics></math>, <math display="inline"><semantics> <msub> <mi>r</mi> <mrow> <mi>o</mi> <mi>n</mi> </mrow> </msub> </semantics></math>, and <math display="inline"><semantics> <msub> <mi>r</mi> <mn>1</mn> </msub> </semantics></math> are among the common interests of researchers. It can be observed that there is a trend that these effects have gradually diminished over the years, even though there may still be a significant effect based on all years of our study. Here, “e-05” indicates “<math display="inline"><semantics> <mrow> <mo>×</mo> <msup> <mn>10</mn> <mrow> <mo>−</mo> <mn>5</mn> </mrow> </msup> </mrow> </semantics></math>”, and similarly for the others.</p>
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<p>Conditional effect plots for days with small and large overnight returns. Here, “e-05” indicates “<math display="inline"><semantics> <mrow> <mo>×</mo> <msup> <mn>10</mn> <mrow> <mo>−</mo> <mn>5</mn> </mrow> </msup> </mrow> </semantics></math>”, and similarly for the others.</p>
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<p>This diagram illustrates the cumulative performance of the strategies <math display="inline"><semantics> <mrow> <mover accent="true"> <mi>η</mi> <mo>˚</mo> </mover> <mrow> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>o</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>o</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>3</mn> <mo>,</mo> <mn>3</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>3</mn> <mo>,</mo> <mn>12</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>5</mn> <mo>,</mo> <mn>3</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>5</mn> <mo>,</mo> <mn>12</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mover accent="true"> <mi>η</mi> <mo>˚</mo> </mover> <mrow> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>l</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> <mo>)</mo> </mrow> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>l</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, and benchmark AL in daily resolution. Specifics on those strategies can be found in <a href="#risks-12-00180-t004" class="html-table">Table 4</a>.</p>
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<p>The market’s intraday momentum strategy performance in yearly resolution. This diagram illustrates the cumulative performance of the <math display="inline"><semantics> <mrow> <mover accent="true"> <mi>η</mi> <mo>˚</mo> </mover> <mrow> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>o</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>o</mi> <mi>n</mi> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>3</mn> <mo>,</mo> <mn>3</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>3</mn> <mo>,</mo> <mn>12</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>5</mn> <mo>,</mo> <mn>3</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>T</mi> <mrow> <mn>5</mn> <mo>,</mo> <mn>12</mn> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mover accent="true"> <mi>η</mi> <mo>˚</mo> </mover> <mrow> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>l</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> <mo>)</mo> </mrow> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>η</mi> <mo>(</mo> <msub> <mi>r</mi> <mrow> <mi>l</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> <mo>)</mo> </mrow> </semantics></math> strategies, as well as the AL benchmark strategy on a yearly basis.</p>
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<p>This diagram illustrates the cumulative performance of aggressive strategies based on the GLR3 and BLRT3 models. Gray and black lines represent the aggressive strategy observed based on GLR3 and BLRT3, respectively. The cumulative returns were calculated since 2010, we only visualize the part starting in 2017 since the proposed strategies use the same trading signals before 2017. This plot indicates that both strategies show a trend of “up” and “down” after 2018, but the strategies proposed by the Student-<span class="html-italic">t</span> model are much more conservative and only pick up four strategies and lead to a smaller variance. However, the Gaussian model leads to many more strategies that generate much higher variability and are therefore more risky to use.</p>
Full article ">Figure A1
<p>QQ plot for the multiple linear regression with Gaussian error terms. It is clear that the tails of the returns are very heavy and the Gaussian multiple linear regression model cannot well capture the tails, and thus the significance suggested by such a model would be misleading.</p>
Full article ">Figure A2
<p>Both PSIS diagnostic plot (left) and the posterior predictive check plot (right, aka, pp check plot) suggest that the fitting of the Bayesian linear model is satisfactory. There are 100 draws for the pp check plot. Note that, the x-axis of the pp check plot has been truncated to cover from −10 to 10 to facilitate the visualization of the plot. The degree of freedom of the Student-<span class="html-italic">t</span> distribution was very small, suggesting a very heavy tail and thus there were actually several numbers with larger absolute values drawn but excluded from the plot.</p>
Full article ">Figure A3
<p>Posterior distributions of the parameters of the Bayesian linear model. All posterior distributions appear to behave well and thus can be used to calculate posterior properties, such as credible intervals of the parameters.</p>
Full article ">Figure A4
<p>Credible intervals for all scaled explanatory variables in the Bayesian linear regression model with Student-<span class="html-italic">t</span> errors, based on the complete scaled dataset. It shows the <math display="inline"><semantics> <mrow> <mn>5</mn> <mo>%</mo> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mn>50</mn> <mo>%</mo> </mrow> </semantics></math>, and <math display="inline"><semantics> <mrow> <mn>95</mn> <mo>%</mo> </mrow> </semantics></math> quantiles of the posterior of the regression coefficients. The quantiles were calculated for each ETF separately.</p>
Full article ">Figure A5
<p>This figure displays the <math display="inline"><semantics> <mrow> <mn>95</mn> <mo>%</mo> </mrow> </semantics></math> confidence intervals of the explanatory variables in the Gaussian linear regression model, using a rolling window of 3 years with SPY data. A bar intersecting the red line indicates that the variable is not statistically significant, and significant otherwise.</p>
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31 pages, 4906 KiB  
Article
The Impact of Residential Building Insulation Standards on Indoor Thermal Environments and Heat-Related Illness Risks During Heatwaves: A Case Study in Korea
by Hee Jung Ham, Sungsu Lee and Ho-Jeong Kim
Sustainability 2024, 16(22), 9831; https://doi.org/10.3390/su16229831 - 11 Nov 2024
Viewed by 413
Abstract
This study investigates the impact of building insulation standards on indoor thermal environments and the risk of heat-related illnesses during heatwaves in South Korea. Indoor temperatures were measured in residential buildings located in Chuncheon and Gwangju during the 2022 heatwave, with outdoor temperature [...] Read more.
This study investigates the impact of building insulation standards on indoor thermal environments and the risk of heat-related illnesses during heatwaves in South Korea. Indoor temperatures were measured in residential buildings located in Chuncheon and Gwangju during the 2022 heatwave, with outdoor temperature data sourced from the Korea Meteorological Administration. Probability distribution fitting was used to estimate the likelihood of indoor temperatures exceeding the critical threshold of 27 °C. Additionally, a linear regression analysis was conducted to examine the relationship between the probability of exceeding the threshold and heat-related illness data from 2017 to 2023 provided by the Korea Disease Control and Prevention Agency. The findings reveal significant variations in indoor thermal conditions during heatwaves, influenced by factors such as building type, year of construction, and climate region, which affect the thermal insulation performance. Buildings with a lower thermal insulation performance were associated with higher indoor temperatures, increasing the likelihood of exceeding the critical threshold and contributing to a higher incidence of heat-related illnesses, particularly in provincial non-metropolitan areas. These results underscore the need for region-specific building insulation standards that address both winter energy efficiency and summer heatwave resilience. Enhancing thermal insulation in vulnerable regions could significantly reduce the risk of heat-related illnesses and improve public health resilience to extreme heat events. Full article
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<p>Flowchart illustrating the study’s assessment of the impact of thermal insulation performance standards on indoor thermal environments during heatwaves (<b>top</b>) and the influence of the standards on indoor thermal exposures and the occurrence of heat-related illnesses during heatwaves (<b>bottom</b>).</p>
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<p>The three climate regions (Central, Southern, and Jeju) and administrative districts (provinces and metropolitan cities) [<a href="#B24-sustainability-16-09831" class="html-bibr">24</a>], with experimental regions marked with circles.</p>
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<p>Locations of residential buildings, weather stations, and representative buildings where experiments were conducted (top: Chuncheon; bottom: Gwangju) (NTS).</p>
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<p>Tzone TempU 03 temperature data logger.</p>
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<p>Cumulative density function of indoor-to-outdoor temperature ratio (thermal transmittance: 0.76 W/m<sup>2</sup>·K).</p>
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<p>Schematics of the methodology for simulating indoor temperatures and the probability of exceeding the threshold temperature during heatwaves.</p>
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<p>Step-by-step process for analyzing correlations between regions.</p>
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<p>Relationship between air conditioning usage and daily average indoor temperature.</p>
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<p>Simulated probability of exceeding the indoor threshold temperature (27 °C) during heatwaves based on building thermal insulation performance.</p>
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<p>Regression analysis between the average probability of exceeding the indoor threshold temperature and the number of indoor heat-related illnesses across regions.</p>
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16 pages, 1460 KiB  
Article
SOCS3 Methylation Partially Mediated the Association of Exposure to Triclosan but Not Triclocarban with Type 2 Diabetes Mellitus: A Case-Control Study
by Qian Gao, Changsheng Huan, Zexin Jia, Qingqing Cao, Pengcheng Yuan, Xin Li, Chongjian Wang, Zhenxing Mao and Wenqian Huo
Int. J. Mol. Sci. 2024, 25(22), 12113; https://doi.org/10.3390/ijms252212113 - 11 Nov 2024
Viewed by 515
Abstract
This study aimed to evaluate the association of TCs (triclosan (TCS) and triclocarban) exposure with T2DM and glucose metabolism-related indicators and the mediating effect of SOCS3 methylation on their associations. A total of 956 participants (330 T2DM and 626 controls) were included in [...] Read more.
This study aimed to evaluate the association of TCs (triclosan (TCS) and triclocarban) exposure with T2DM and glucose metabolism-related indicators and the mediating effect of SOCS3 methylation on their associations. A total of 956 participants (330 T2DM and 626 controls) were included in this case-control study. Logistic regression and generalized linear models were used to assess the effect of TCs on T2DM and glucose metabolism-related indicators. The dose–response relationship between TCs and T2DM was analyzed by restricted cubic spline. Finally, after evaluating the association between TCs and SOCS3 methylation levels, the mediating effect of SOCS3 methylation on the TC−associated T2DM was estimated. Each 1-unit increase in TCS levels was associated with a 13.2% increase in the risk of T2DM (OR = 1.132, 95% CI: 1.062, 1.207). A linear dose–response relationship was found between TCS and T2DM. TCS was negatively associated with Chr17:76356190 methylation. Moreover, mediation analysis revealed that Chr17:76356190 methylation mediated 14.54% of the relationship between TCS exposure and T2DM. Exposure to TCS was associated with a higher prevalence of T2DM. SOCS3 methylation partially mediated the association of TCS with T2DM. Our findings may provide new insights into the treatment of T2DM, and the study of the biological mechanisms of T2DM. Full article
(This article belongs to the Special Issue Progress in Research on Endocrine-Disrupting Chemicals)
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<p>Dose–response relationship of Ln-TCScrea with T2DM and glucose metabolism-related indicators.</p>
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<p>Mediating role of the methylation level of <span class="html-italic">Chr17:76356190</span> or <span class="html-italic">Chr17:76356199</span> between the association of Ln-TCScrea with T2DM and its glucose metabolism-related indicators.</p>
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<p>The flowchart of the inclusion and exclusion of participants. Abbreviations: T2DM, type 2 diabetes mellitus; TCS, triclosan.</p>
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12 pages, 2092 KiB  
Article
Evaluation of the Changes in the Strength of Clay Reinforced with Basalt Fiber Using Artificial Neural Network Model
by Yasemin Aslan Topçuoğlu, Zeynep Bala Duranay and Zülfü Gürocak
Appl. Sci. 2024, 14(22), 10362; https://doi.org/10.3390/app142210362 - 11 Nov 2024
Viewed by 374
Abstract
In this research, the impact of basalt fiber reinforcement on the unconfined compressive strength of clay soils was experimentally analyzed, and the collected data were utilized in an artificial neural network (ANN) to predict the unconfined compressive strength based on the basalt fiber [...] Read more.
In this research, the impact of basalt fiber reinforcement on the unconfined compressive strength of clay soils was experimentally analyzed, and the collected data were utilized in an artificial neural network (ANN) to predict the unconfined compressive strength based on the basalt fiber reinforcement ratio and length. For this purpose, two different lengths of basalt fiber (6 mm and 12 mm) were added to unreinforced bentonite clay at ratios of 0%, 1%, 2%, 3%, 4%, and 5%, and unconfined compressive tests were performed on the prepared reinforced clay samples to determine the unconfined compressive strength (qu) values. The evaluation of the obtained experimental results was carried out by creating ANN models. To validate the prediction capabilities of the ANN, a comparative analysis was performed using linear regression, support vector machines, and Gaussian process regression models. Ultimately, a five-fold cross-validation technique was employed to objectively evaluate the overall performance of the model. The evaluations revealed that the ANN model predictions using data obtained from experimental studies showed the highest accuracy and were in close agreement with the experimental results. Full article
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<p>ANN diagram implemented in the system.</p>
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<p>The ANN architecture.</p>
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<p>ANN outputs corresponding to sample input values.</p>
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<p>The R values for training, validation, test, and all datasets.</p>
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<p>The test regression plot.</p>
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<p>Five-fold-cross-validation response plot.</p>
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25 pages, 1326 KiB  
Article
Evidential Analysis: An Alternative to Hypothesis Testing in Normal Linear Models
by Brian Dennis, Mark L. Taper and José M. Ponciano
Entropy 2024, 26(11), 964; https://doi.org/10.3390/e26110964 - 10 Nov 2024
Viewed by 391
Abstract
Statistical hypothesis testing, as formalized by 20th century statisticians and taught in college statistics courses, has been a cornerstone of 100 years of scientific progress. Nevertheless, the methodology is increasingly questioned in many scientific disciplines. We demonstrate in this paper how many of [...] Read more.
Statistical hypothesis testing, as formalized by 20th century statisticians and taught in college statistics courses, has been a cornerstone of 100 years of scientific progress. Nevertheless, the methodology is increasingly questioned in many scientific disciplines. We demonstrate in this paper how many of the worrisome aspects of statistical hypothesis testing can be ameliorated with concepts and methods from evidential analysis. The model family we treat is the familiar normal linear model with fixed effects, embracing multiple regression and analysis of variance, a warhorse of everyday science in labs and field stations. Questions about study design, the applicability of the null hypothesis, the effect size, error probabilities, evidence strength, and model misspecification become more naturally housed in an evidential setting. We provide a completely worked example featuring a two-way analysis of variance. Full article
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<p>Probability density functions (solid curves) of the noncentral F(<math display="inline"><semantics> <mrow> <mi>q</mi> <mrow> <mo>,</mo> <mo> </mo> </mrow> <mi>n</mi> <mo>−</mo> <mi>r</mi> <mrow> <mo>,</mo> <mo> </mo> </mrow> <mi>λ</mi> </mrow> </semantics></math>) distribution for various values of sample size <math display="inline"><semantics> <mi>n</mi> </semantics></math> and the noncentrality parameter <math display="inline"><semantics> <mi>λ</mi> </semantics></math>, as represented in the formula for <math display="inline"><semantics> <mrow> <mi>f</mi> <mfenced> <mi>u</mi> </mfenced> </mrow> </semantics></math> in the text, Equation (30). Here, <math display="inline"><semantics> <mrow> <mi>λ</mi> <mo>=</mo> <mi>n</mi> <msup> <mi>δ</mi> <mn>2</mn> </msup> </mrow> </semantics></math>, which is in the common form of a simple experimental design, where <math display="inline"><semantics> <mi>n</mi> </semantics></math> is the number of observations and <math display="inline"><semantics> <mrow> <msup> <mi>δ</mi> <mn>2</mn> </msup> </mrow> </semantics></math> is a generalized squared per-observation effect size. The cumulative distribution function of the noncentral F distribution, exemplified here as the area under each density curve to the left of the dashed vertical line, is a monotone decreasing function of <math display="inline"><semantics> <mi>n</mi> </semantics></math>. Here, <math display="inline"><semantics> <mrow> <mi>q</mi> <mo>=</mo> <mn>6</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mi>r</mi> <mo>=</mo> <mn>12</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <msup> <mi>δ</mi> <mn>2</mn> </msup> <mo>=</mo> <mn>0.25</mn> </mrow> </semantics></math>, and <math display="inline"><semantics> <mi>n</mi> </semantics></math> has the values <math display="inline"><semantics> <mrow> <mn>24</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mn>36</mn> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <mn>48</mn> </mrow> </semantics></math>, and <math display="inline"><semantics> <mrow> <mn>60</mn> </mrow> </semantics></math>. Dashed curve is the density function for the F(<math display="inline"><semantics> <mrow> <mi>q</mi> <mrow> <mo>,</mo> <mo> </mo> </mrow> <mi>n</mi> <mo>−</mo> <mi>r</mi> <mrow> <mo>,</mo> <mo> </mo> </mrow> <mi>λ</mi> </mrow> </semantics></math>) distribution with <math display="inline"><semantics> <mrow> <mi>n</mi> <mo>=</mo> <mn>24</mn> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msup> <mi>δ</mi> <mn>2</mn> </msup> <mo>=</mo> <mn>0</mn> </mrow> </semantics></math> (central F distribution). Notice that for a given effect size, the noncentral distribution increasingly diverges from the central distribution as sample size increases.</p>
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<p>Curves: Estimated cdf of <math display="inline"><semantics> <mrow> <mo>Δ</mo> <mi>SIC</mi> </mrow> </semantics></math> for the citrus tree example (two-factor analysis of variance, <a href="#entropy-26-00964-t001" class="html-table">Table 1</a>, with model 1 representing no interactions, model 2 representing interactions) using parametric (solid) and nonparametric (dashed) bootstrap with <math display="inline"><semantics> <mrow> <mn>1024</mn> </mrow> </semantics></math> bootstrap samples. Dotted horizontal lines depict 0.05 and 0.95 levels.</p>
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<p>The effect of sample size on the uncertainty of an evidential estimation. The data are simulated from the estimated model 2 (representing interactions). For each data set, confidence intervals were generated with 1024 bootstraps. To depict the expected behavior of such intervals the confidence points from 1024 simulated data sets are averaged. The vertical lines indicate the average 90% confidence intervals. The open circles and the dashes indicate the average location of the 50% confidence point. The solid horizontal line indicates equal evidence for model 1 and model 2. The dotted horizontal line indicates the pseudo-true difference of Kullback–Leibler divergences in the simulations.</p>
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<p>Interaction plot. An interaction plot is a graphical display of the potential magnitude and location of interaction in a linear model. For a two-factor ANOVA, a basic interaction plot displays a central measure for each cell (generally mean or median) on the <span class="html-italic">Y</span>-axis plotted against a categorical factor indicated on the <span class="html-italic">X</span>-axis. The second factor is indicated by lines joining cells that share a factor level. If there is no interaction, these lines will be parallel. The stronger an interaction, the greater the deviation from parallelism will be. Of course, some deviation may result from error in the estimation of cell central values. As consequence, interaction plots often include a display, such as a boxplot or confidence interval, of the uncertainty in the estimate of cell central value. In this figure, we plot 95% confidence intervals of cell means. Because replication is low (2 observations per cell), we calculate these intervals using a pooled estimate of the standard error. We further enhance this plot by including confidence intervals on the slope of the lines. If one considers any value within an interval for a central value a plausible value, a line from any plausible central value to any plausible value in the next interval represents a plausible slope. The maximum plausible slope runs from the lower bound on the left to the upper bound on the right. Similarly, the minimum plausible slope runs from the upper bound on the left to the lower bound on the right. If the intervals on central values are confidence intervals, then these maximum and minimum plausible slopes are themselves a pair confidence bounds on the slopes whose confidence level is equal to the square of the central value interval confidence level. Since in the figure we are using 95% intervals on the cell means, the confidence level on slopes is 90.5%. In the case study of citrus yields, the interaction plot readily shows that small changes in the cell mean yields well within the uncertainties in cell means could make all lines parallel. This interpretation matches the quantitative estimate of very low evidence for interactions.</p>
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18 pages, 3600 KiB  
Article
Examining the Potential of Biogas: A Pathway from Post-Fermented Waste into Energy in a Wastewater Treatment Plant
by Krzysztof Michalski, Magdalena Kośka-Wolny, Krzysztof Chmielowski, Dawid Bedla, Agnieszka Petryk, Paweł Guzdek, Katarzyna Anna Dąbek, Michał Gąsiorek, Klaudiusz Grübel and Wiktor Halecki
Energies 2024, 17(22), 5618; https://doi.org/10.3390/en17225618 - 10 Nov 2024
Viewed by 688
Abstract
Biogas has improved due to technological advancements, environmental awareness, policy support, and research innovation, making it a more cost-effective and environmentally friendly renewable energy source. The Generalized Linear Model (GLM) was employed to examine the relationship between purchased and generated energy from 2007 [...] Read more.
Biogas has improved due to technological advancements, environmental awareness, policy support, and research innovation, making it a more cost-effective and environmentally friendly renewable energy source. The Generalized Linear Model (GLM) was employed to examine the relationship between purchased and generated energy from 2007 to 2023. Metrics such as deviance, log likelihood, and dispersion phi were examined to assess model fit. The Mann–Kendall test was utilized to detect trends in energy datasets. Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) reduction was significant, exceeding 97% from 2014 to 2023. However, treated sewage displayed limited susceptibility to biological degradation, with COD to BOD5 ratios increasing from 2.28 to 6.59 for raw sewage and from 2.33 to 7.05 for treated sewage by 2023. Additionally, the efficiency of sewage purification processes was calculated, and multivariate regression analysis was conducted on gas composition data. Principal Coordinate Ordination (PCO) and k-means clustering were used for dimensionality reduction and biogas component clustering, respectively. This research showed that biogas from the waste water treatment process can be used, particularly in methane production. Technological advancements have made biogas production more efficient, enhancing energy generation within a circular economy framework. Full article
(This article belongs to the Special Issue Sustainable Biomass Energy Production and Utilization)
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<p>A technological procedure in the wastewater treatment plant.</p>
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<p>Amount of waste for fermentation during the study period.</p>
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<p>The average annual energy consumption during the research period. Log likelihood = −7; G-statistics = 0.219; <span class="html-italic">p</span> = 0.639.</p>
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<p>Main components of the biogas produced in the technological process (n = 203).</p>
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<p>Relationship between calorific value and methane content.</p>
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<p>Amount of waste received for co-fermentation in the years 2014–2023 with a 5-year forecast.</p>
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<p>PCO for biogas composition: red diamonds represent heating value, blue squares denote methane, black squares stand for hydrogen sulfide, and green stars symbolize oxygen.</p>
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<p>K-means analysis for clustering biogas components.</p>
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12 pages, 481 KiB  
Article
Improvements in Insulin Resistance and Glucose Metabolism Related to Breastfeeding Are Not Mediated by Subclinical Inflammation
by Julia Martins de Oliveira, Patrícia Médici Dualib, Alexandre Archanjo Ferraro, Rosiane Mattar, Sérgio Atala Dib and Bianca de Almeida-Pititto
Metabolites 2024, 14(11), 608; https://doi.org/10.3390/metabo14110608 - 9 Nov 2024
Viewed by 442
Abstract
Background: Lactation is known to improve insulin resistance, but this phenomenon remains poorly understood. Our goal was to evaluate whether subclinical inflammation could mediate the association between breastfeeding (BF) and improvement in glucose metabolism and markers of insulin resistance (MIRs) in the postpartum. [...] Read more.
Background: Lactation is known to improve insulin resistance, but this phenomenon remains poorly understood. Our goal was to evaluate whether subclinical inflammation could mediate the association between breastfeeding (BF) and improvement in glucose metabolism and markers of insulin resistance (MIRs) in the postpartum. Methods: A total of 95 adult women (≥18 years) with a BMI ≥ 25 kg/m2 from the outpatient clinic of the Federal University of São Paulo were followed from early pregnancy until 60 to 180 days postpartum. The patients were divided based on their BF status: BF and non-BF groups. A latent variable termed SubInf was created incorporating inflammation-related biomarkers: adiponectin, E-selectin, branched-chain amino acids, zonulin, copeptin, and lipopolysaccharides. The association of BR with MIRs in the postpartum was evaluated through linear regression analysis, and mediation analysis was performed to evaluate the role of SubInf in this association. Results: The groups were similar regarding gestational diabetes mellitus (GDM) prevalence, pre-gestational BMI, caloric intake, physical activity, and postpartum weight loss. The BF group presented lower levels of triglycerides (TGs), fasting glucose, fasting insulin, TG/HDLcholesterol ratio (TG/HDL), TyG index, and HOMA-IR compared to the non-BF group. A linear regression analysis adjusted for scholarity, parity, pre-gestational BMI, GDM, weight gain during pregnancy, and mode of delivery revealed an inverse association between BF and fasting glucose [−6.30 (−10.71 to −1.89), p = 0.005), HOMA-IR [−0.28 (−0.50 to −0.05), p = 0.017], TyG index [−0.04 (−0.06 to −0.01), p = 0.002], and TG/HDL ratio [−0.23 (−0.46 to −0.01), p = 0.001]. In the mediation analysis, SubInf did not mediate the indirect effect of BF on MIRs. Conclusions: In overweight and obese women, an association between BF and improvement in MIRs in the postpartum was seen, corroborating that BF should be stimulated, especially in these cardiometabolic high-risk women. Subclinical inflammation did not seem to mediate this association. Full article
(This article belongs to the Special Issue Glucose Metabolism in Pregnancy)
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<p>Flowchart graph of our study.</p>
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20 pages, 7643 KiB  
Article
Research on Reactivity-Equivalent Physical Transformation Method for Double Heterogeneity in Pressurized Water Reactors Based on Machine Learning
by Song Li, Jiannan Li, Lei Liu, Baocheng Huang, Ling Chen, Yongfa Zhang, Jianli Hao and Yunfei Zhang
Processes 2024, 12(11), 2493; https://doi.org/10.3390/pr12112493 - 9 Nov 2024
Viewed by 341
Abstract
Traditional computational methods for pressurized water reactors are unable to handle dispersed fuel particles as the double heterogeneity and the direct volumetric homogenization can result in significant errors. In contrast, reactivity-equivalent physical transformation techniques offer high precision for addressing the double heterogeneity introduced [...] Read more.
Traditional computational methods for pressurized water reactors are unable to handle dispersed fuel particles as the double heterogeneity and the direct volumetric homogenization can result in significant errors. In contrast, reactivity-equivalent physical transformation techniques offer high precision for addressing the double heterogeneity introduced by dispersed fuel particles. This approach converts the double heterogeneity problem into a single heterogeneity problem, which is then subsequently investigated by using the conventional pressurized water reactor computational procedure. However, it is currently empirical and takes a lot of time to obtain the right k. In this paper, we train the RPT model by using the existing dataset of plate-dispersed fuel and rod-dispersed fuel by a machine learning method based on a linear regression model, and we then use the new data to make predictions and derive the corresponding similarity ratios. The burnup verification, density verification, fission rate verification, and neutron energy spectrum analysis are calculated through the OpenMC program. For plate-type fuel elements, the method maintains an accuracy within 200 pcm during depletion, with deviations in the 235U density and 235U fission rate within 0.1% and neutron energy spectrum errors within 6%. For rod-type fuel elements, the method maintains an accuracy within 100 pcm during depletion, with deviations in 235U and 239Pu density within 1.5% and neutron energy spectrum errors within 1%. The numerical validation indicates that the reactivity-equivalent physical transformation method based on the linear regression model not only greatly improves the computational efficiency, but also ensures a very high accuracy to deal with double heterogeneity in nuclear reactors. Full article
(This article belongs to the Section Advanced Digital and Other Processes)
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<p>Basic principles of the RPT method for rod elements.</p>
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<p>Basic principles of the plate-type component RPT method.</p>
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<p>Similarity ratio of the plate RPT model.</p>
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<p>Flowchart of applying machine learning models.</p>
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<p>Similarity ratio of the rod RPT model.</p>
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<p>Variation with burnup for minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation with burnup at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U density with burnup at the minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U density with burnup at the maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U fission rate with burnup at the minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U fission rate with burnup at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation in neutron flux with neutron energy at minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation in neutron flux with neutron energy at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation with burnup for minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation with burnup at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U density with burnup at the minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>235</sup>U density with burnup at the maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>239</sup>Pu density with burnup at the minimum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation of <sup>239</sup>Pu density with burnup at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation in neutron flux with energy at the minimum of <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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<p>Variation in neutron flux with energy at maximum <span class="html-italic">k</span><sub>inf</sub> deviation.</p>
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29 pages, 2679 KiB  
Article
Fault Diagnosis in a Four-Arm Delta Robot Based on Wavelet Scattering Networks and Artificial Intelligence Techniques
by Claudio Urrea and Carlos Domínguez
Technologies 2024, 12(11), 225; https://doi.org/10.3390/technologies12110225 - 8 Nov 2024
Viewed by 468
Abstract
This paper presents a comprehensive fault diagnosis approach for a delta robot utilizing advanced feature extraction and classification techniques. A four-arm delta robot prototype is designed in SolidWorks for realistic fault analysis. Two case studies investigate faults through control effort and vibration signals, [...] Read more.
This paper presents a comprehensive fault diagnosis approach for a delta robot utilizing advanced feature extraction and classification techniques. A four-arm delta robot prototype is designed in SolidWorks for realistic fault analysis. Two case studies investigate faults through control effort and vibration signals, with control effort detecting motor and encoder faults, while vibration signals identify bearing faults. This study compares time-domain signal features and wavelet scattering networks, applied by classification algorithms including wide neural networks (WNNs), efficient linear support vector machine (ELSVM), efficient logistic regression (ELR), and kernel naive Bayes (KNB). Results indicate that a WNN, using wavelet scattering features ranked by one-way anova, is optimal due to its consistency and reliability, while these features enhance computational efficiency by reducing classifier size. Sensitivity analysis demonstrates the classifier’s capacity to detect untrained faults, highlighting the importance of effective feature extraction and classification methods for fault diagnosis in complex robotic systems. This research significantly contributes to fault diagnosis in delta robots and lays the groundwork for future studies on fault tolerance control and predictive maintenance planning. Future work will focus on the physical implementation of the delta robot in laboratory settings, aiming to improve operational efficiency and reliability in industrial applications. Full article
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<p>Delta robot design exported to Simscape.</p>
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<p>Final assembly of the delta robot exported from SolidWorks.</p>
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<p>Outputs of the joints in case of failure in actuator 4.</p>
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<p>Control effort outputs in case of failure in actuator 4.</p>
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<p>Control effort in the event of medium magnitude sensor failure.</p>
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<p>Bearings at actuated joint of the Delta robot.</p>
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<p>Elements susceptible to failure in a bearing.</p>
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<p>Vibration without faults.</p>
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<p>BPFI fault.</p>
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<p>BPFO fault.</p>
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<p>BSF fault.</p>
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<p>FTF fault.</p>
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<p>Vibration with BPFI fault.</p>
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<p>Vibration with BPFO fault.</p>
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<p>Vibration with BSF fault.</p>
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<p>Vibration with FTF fault.</p>
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<p>Scaling function and wavelets for Case 1.</p>
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<p>Scaling function and wavelets for Case 2.</p>
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<p>Logarithmic distance analysis of the delta robot under initial condition perturbation.</p>
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<p>Logarithmic distance analysis of the delta robot under fault condition.</p>
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<p>Classification of Case 1 training for WNN using wavelet scattering networks features ranked with one-way anova.</p>
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<p>Classification of Case 1 test for WNN using wavelet scattering networks features ranked with one-way anova.</p>
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<p>Classification of training and test data in Case 2 for WNN using wavelet scattering networks features ranked with one-way anova.</p>
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<p>Algorithm size for Case 1.</p>
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<p>Algorithm size for Case 2.</p>
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<p>Untrained fault classification with WNN using wavelet scattering networks features ranked with one-way anova.</p>
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15 pages, 1204 KiB  
Article
Association of Dietary Patterns, C-Reactive Protein, and Risk of Obesity Among Children Aged 9–17 Years in Guangzhou, China: A Cross-Sectional Mediation Study
by Zheng Su, Chunzi Zeng, Jie Huang, Shiyun Luo, Jiaying Guo, Jinhan Fu, Weiwei Zhang, Zhoubin Zhang, Bo Zhang and Yan Li
Nutrients 2024, 16(22), 3835; https://doi.org/10.3390/nu16223835 - 8 Nov 2024
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Abstract
Background: Childhood obesity is a major public health challenge in the 21st century, and diet is one of the key modifiable factors in its prevention. This study examined the link between dietary patterns of children and general and central obesity, including the role [...] Read more.
Background: Childhood obesity is a major public health challenge in the 21st century, and diet is one of the key modifiable factors in its prevention. This study examined the link between dietary patterns of children and general and central obesity, including the role of C-reactive protein (CRP). Methods: This study enrolled 2413 children aged 9–17. Anthropometric measurements, CRP levels, and dietary data were collected. Factor analysis identified dietary patterns, and logistic regression examined the association between CRP levels and childhood obesity. Multiple linear regression determined the correlation between dietary patterns and CRP. Mediation analysis assessed the role of CRP in the link between dietary patterns and childhood obesity. Results: Three dietary patterns were identified. The rice and meat pattern was significantly correlated to the risk of childhood obesity (OR = 1.166, 95%CI: 1.000, 1.359 for general obesity; OR = 1.215, 95%CI: 1.071, 1.377 for central obesity). CRP was positively correlated with childhood obesity risk (OR = 2.301, 95%CI: 1.776, 2.982 for general obesity; OR = 2.165, 95%CI: 1.738, 2.697 for central obesity). The fruit and vegetable pattern was inversely related to CRP (β= −0.059, 95%CI: −0.081, −0.036), while the snack pattern was positively correlated (β= 0.043, 95%CI: 0.020, 0.065). CRP had a suppressive effect on the association between the fruit and vegetable pattern and snack pattern with childhood obesity. Conclusions: This study revealed the rice and meat pattern as a risk factor for childhood obesity, and cross-sectional evidence linked the fruit and vegetable pattern and snack pattern to childhood obesity risk, mediated by CRP. Full article
(This article belongs to the Section Pediatric Nutrition)
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<p>Flowchart of the subject selection process.</p>
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<p>Conditional probability distribution of three latent classes.</p>
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<p>Radar charts of different dietary patterns obtained from factor analysis.</p>
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