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Keywords = inductive flow measurement

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18 pages, 2511 KiB  
Article
Tetrahydrofurfuryl Nitrate: A New Organic Nitrate Induces Hypotension and Vasorelaxation Without Vascular Tolerance Induction
by Maria do Carmo de Alustau-Fernandes, Fabíola Fialho Furtado Gouvêa, Natália Tabosa Machado Calzerra, Tays Amanda Felisberto Gonçalves, Valéria Lopes de Assis, Walma Pereira de Vasconcelos, Petrônio Filgueiras de Athayde-Filho, Robson Cavalcante Veras, Thyago Moreira de Queiroz and Isac Almeida de Medeiros
J. Vasc. Dis. 2024, 3(4), 453-470; https://doi.org/10.3390/jvd3040034 - 20 Nov 2024
Viewed by 457
Abstract
The development of new organic nitrates is still relevant due to the clinical limitations of their use. Tetrahydrofurfuryl nitrate (NTHF) is a new organic nitrate obtained through a synthetic route of sugarcane. The aim of this research was to investigate the cardiovascular effects [...] Read more.
The development of new organic nitrates is still relevant due to the clinical limitations of their use. Tetrahydrofurfuryl nitrate (NTHF) is a new organic nitrate obtained through a synthetic route of sugarcane. The aim of this research was to investigate the cardiovascular effects promoted by NTHF in rats. Isolated vascular smooth muscle cells (VSMC) were incubated with a specific probe and were analyzed in a flow cytometer to measure the NO concentration after NTHF treatment. Rat superior mesenteric rings were isolated and used for isometric tension recordings and the evaluation of the vasorelaxant activity induced by NTHF. For the in vivo study, polyethylene catheters were implanted into the abdominal aorta and inferior vena cava of the rats (weighing 250–300 g). NTHF increased NO levels in rat VSMCs. In anesthetized rats, NTHF induced hypotension and bradycardia after intravenous administration. These effects were attenuated after the administration of a sGC inhibitor, methylene blue. In the phenylephrine pre-contracted superior mesenteric artery of rats, NTHF (1 pM–10 μM) induced concentration-dependent vasodilatation in both the intact and removed endothelium. Furthermore, in the presence of NO° scavenging (C-PTIO and HDX) or ODQ, a sGC inhibitor, the vasorelaxation induced by NTHF was decreased. NTHF tolerance was evaluated in mesenteric artery rings previously exposed with isolated concentrations of the new organic nitrate. The vasorelaxant effect was not modified by exposure to nitrate. These results demonstrated that NTHF induced hypotension and bradycardia in vivo and a vasorelaxant effect with the participation of the NO-sGC-PKG pathway and triggering calcium-activated K+ channels without vascular tolerance induction. Full article
(This article belongs to the Section Cardiovascular Diseases)
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<p>Chemical structure of tetrahydrofurfuryl nitrate (NTHF).</p>
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<p>Release of NO by nitrates in rat aortic VSMC. Effect of NTHF (100 µM), SNP (10 µM) and GTN (10 µM) in the generation of NO in rat aortic VSMC, DAF-2DA loaded and analyzed by flow cytometry after 30 min incubation. The percentage of the difference in fluorescence intensity (%), which reflects the increase in the [NO]C, was obtained for each protocol. The data are representative of four experiments (different primary cultures). Values expressed as mean ± E.P.M. * <span class="html-italic">p</span> &lt; 0.05 versus vehicle.</p>
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<p>Changes in the arterial mean pressure (MAP) and heart rate (HR) induced by NTHF. Effect promoted by bolus administration of NTHF (10, 20, 30, 40 and 50 mg/kg, i.v.) (n = 6) on MAP (<b>A</b>) and HR (<b>B</b>) in unanesthetized normotensive rats in the absence or presence of Methylene Blue (3 mg/Kg; i.v.). These data were examined using one-way ANOVA followed by the Bonferroni’s post-test. * <span class="html-italic">p</span> &lt; 0.05 versus NTHF alone.</p>
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<p>Vasodilator effect of NTHF in isolated rat mesenteric rings. Concentration–response curves showing the vasorelaxant effect induced by NTHF (10<sup>−12</sup>–10<sup>−5</sup> M) in mesenteric rings pre-contracted with phenylephrine (1 µM) in the presence (n = 6; ●) or absence (n = 6; □) of functional endothelium. Values are expressed by mean ± S.E.M. The data were examined using Student’s <span class="html-italic">t</span>-test.</p>
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<p>Concentration–response curves showing the involvement of NO/sGC/cGMP pathway in the vasorelaxant effect of NTHF. Relaxation induced by NTHF (10<sup>−12</sup>–10<sup>−5</sup> M) in the endothelium-denuded mesenteric artery rings pre-contracted with Phe (1 µM) in the absence (control; n = 6; □) or in the presence of C-PTIO (300 µM; n = 5; ■), HDX (30 µM; n = 5; ◆) or ODQ (10 µM; n = 5; ▲). Values are expressed by mean ± S.E.M. * <span class="html-italic">p</span> &lt; 0.05 versus control. The data were examined using Student’s <span class="html-italic">t</span>-test.</p>
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<p>Concentration–response curves showing the participation of K<sup>+</sup> channels in the vasodilator effect induced by NTHF. Relaxation induced by NTHF (10<sup>−12</sup>–10<sup>−5</sup> M) in the endothelium-denuded mesenteric artery rings pre-contracted with Phe (1 µM) in the absence (control; n = 6; □) or in the presence of KCl (20 mM; n = 6; ■), TEA (3 mM; n = 6; ○), TEA (1 mM; n = 6; ●), 4-AP (1 mM; n = 6; △), GLI (10 µM; n = 6; ▲), (BaCl<sub>2</sub>; 30 μM n = 6; ◆) or ChTX (100 nM; n = 6; ◇). Values are mean ± S.E.M. * <span class="html-italic">p</span> &lt; 0.05 for versus control. The data were examined using Student’s <span class="html-italic">t</span>-test.</p>
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<p>Concentration–response curves showing the participation of reactive oxygen species (ROS) in the vasorelaxant effect induced by NTHF. Concentration–response curves showing the vasorelaxant effect induced by NTHF (10<sup>−12</sup>–10<sup>−5</sup> M) in mesenteric rings pre-contracted with phenylephrine (1 µM) in the absence (control; n = 6; □) or in the presence of NAC (3 mM; n = 6; ●). Values are expressed by mean ± S.E.M. * <span class="html-italic">p</span> &lt; 0.05 versus control. The data were examined using Student’s <span class="html-italic">t</span>-test.</p>
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<p>NTHF tolerance induced in vitro. Concentration–response curves showing the vasodilator effect induced by NTHF in mesenteric rings previously incubated with NTHF (3, 10, 30 and 100 µM) or vehicle for 1 h and pre-contracted with phenylephrine (1 μM). Values are expressed by mean ± S.E.M. The data were examined using Student’s <span class="html-italic">t</span>-test.</p>
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<p>NTHF-induced hypotension and vasorelaxant effect. The NO<sup>●</sup>, which is released from NTHF molecule, binds into sGC and activates the NO<sup>●</sup>/cGC/PKG pathway and causes subsequent activation of large-conductance Ca<sup>2+</sup>ensitive K<sup>+</sup> channels (BK<sub>Ca2+</sub>). Furthermore, under the experimental conditions performed here, NTHF did not develop vascular tolerance after prolonged exposure to the cumulative concentrations of the organic nitrate.</p>
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17 pages, 740 KiB  
Article
A Phase II, Open-Label Study of Lenalidomide and Dexamethasone Followed by Donor Lymphocyte Infusions in Relapsed Multiple Myeloma Following Upfront Allogeneic Stem Cell Transplant
by Richard LeBlanc, Stéphanie Thiant, Rafik Terra, Imran Ahmad, Jean-Sébastien Claveau, Nadia Bambace, Léa Bernard, Sandra Cohen, Jean-Sébastien Delisle, Silvy Lachance, Thomas Kiss, Denis-Claude Roy, Guy Sauvageau and Jean Roy
Curr. Oncol. 2024, 31(11), 7258-7274; https://doi.org/10.3390/curroncol31110535 - 16 Nov 2024
Viewed by 783
Abstract
Background: To date, the only potential curative treatment for multiple myeloma (MM) remains allogeneic (allo) hematopoietic cell transplant (HCT), although, most patients will eventually relapse. In relapsed patients, donor lymphocyte infusions (DLIs) have been reported to control disease, but the optimal strategy prior [...] Read more.
Background: To date, the only potential curative treatment for multiple myeloma (MM) remains allogeneic (allo) hematopoietic cell transplant (HCT), although, most patients will eventually relapse. In relapsed patients, donor lymphocyte infusions (DLIs) have been reported to control disease, but the optimal strategy prior to and doses of DLIs remain unclear. With this study (NCT03413800), we aimed to investigate the efficacy and toxicity of lenalidomide and dexamethasome (Len/Dex) followed by escalating pre-determined doses of DLIs in MM patients who relapsed after allo HCT. Methods: Patients aged 18–65 years with relapsed MM following upfront tandem autologous (auto)/allo HCT were eligible. Treatment consisted of six cycles of Len/Dex followed by three standardized doses of DLIs: 5 × 106 CD3+/kg, 1 × 107/kg and 5 × 107/kg every 6 weeks. Bone marrow minimal measurable disease (MRD) using flow cytometry (10−5) was performed at enrolment, then every 3 months for 2 years or until disease progression, in a subset of patients. The primary endpoint was efficacy as measured by progression-free survival (PFS) at 2 years following Len/Dex/DLIs. Secondary objectives were safety including GVHD, response including MRD status and overall survival (OS). Results: A total of 22 patients participated in this study, including 62% with high-risk cytogenetics. With a median follow-up of 5.3 years (range: 4.1–6.1), PFS and OS were 26.5% (95% CI: 10.4–45.9%) and 69.2% (95% CI: 43.3–85.1%), respectively. Overall, the best responses achieved post-Len/Dex + DLIs were complete remission in 9.1%, very good partial response in 50%, and progressive disease in 40.9%. Among the nine patients tested for MRD, only two achieved a negative status after receiving DLIs. Six patients died, all due to disease progression. No acute GVHD was observed after DLIs. We report a very low incidence of moderate/severe chronic GVHD of 18.2% with no need for systemic immunosuppressants one year after diagnosis. No unexpected adverse events were observed. Interestingly, a positive correlation between response to Len/Dex re-induction and response to DLIs was found (p = 0.0032). Conclusions: Our findings suggest that Len/Dex/DLIs in second line treatment after upfront tandem auto/allo HCT in relapsed MM patients remains feasible and safe. With a potential correlation between induction chemotherapy and DLI responses, more potent induction regimens together with higher doses of DLIs should be considered in the future. Full article
(This article belongs to the Section Cell Therapy)
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<p>Overall schedule of treatments and measurable residual disease (MRD) assessments.</p>
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<p>Kaplan–Meier estimates of (<b>A</b>) progression-free survival and (<b>B</b>) overall survival after initiation of first cycle of lenalidomide.</p>
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15 pages, 2303 KiB  
Article
The Immunomodulatory Effect of Different FLT3 Inhibitors on Dendritic Cells
by Sebastian Schlaweck, Alea Radcke, Sascha Kampmann, Benjamin V. Becker, Peter Brossart and Annkristin Heine
Cancers 2024, 16(21), 3719; https://doi.org/10.3390/cancers16213719 - 4 Nov 2024
Viewed by 649
Abstract
Background: FMS-like tyrosine kinase 3 (FLT3) mutations or internal tandem duplication occur in 30% of acute myeloid leukemia (AML) cases. In these cases, FLT3 inhibitors (FLT3i) are approved for induction treatment and relapse. Allogeneic hematopoietic stem cell transplantation (alloHSCT) remains the recommended post-induction [...] Read more.
Background: FMS-like tyrosine kinase 3 (FLT3) mutations or internal tandem duplication occur in 30% of acute myeloid leukemia (AML) cases. In these cases, FLT3 inhibitors (FLT3i) are approved for induction treatment and relapse. Allogeneic hematopoietic stem cell transplantation (alloHSCT) remains the recommended post-induction therapy for suitable patients. However, the role of FLT3i therapy after alloHSCT remains unclear. Therefore, we investigated the three currently available FLT3i, gilteritinib, midostaurin, and quizartinib, in terms of their immunosuppressive effect on dendritic cells (DCs). DCs are professional antigen-presenting cells inducing T-cell responses to infectious stimuli. Highly activated DCs can also cause complications after alloHSCT, such as triggering Graft versus Host disease, a serious and potentially life-threatening complication after alloHSCT. Methods: To study the immunomodulatory effects on DCs, we differentiated murine and human DCs in the presence of FLT3i and performed immunophenotyping by flow cytometry and cytokine measurements and investigated gene and protein expression. Results: We detected a dose-dependent immunosuppressive effect of midostaurin, which decreased the expression of costimulatory markers like CD86, and found a reduced secretion of pro-inflammatory cytokines such as IL-12, TNFα, and IL-6. Mechanistically, we show that midostaurin inhibits TLR and TNF signaling and NFκB, PI3K, and MAPK pathways. The immunosuppressive effect of gilteritinib was less pronounced, while quizartinib did not show truncation of relevant signaling pathways. Conclusions: Our results suggest different immunosuppressive effects of these three FLT3i and may, therefore, provide an additional rationale for optimal maintenance therapy after alloHSCT of FLT3-positive AML patients to prevent infectious complications and GvHD mediated by DCs. Full article
(This article belongs to the Special Issue Advancements in Treatment Approaches for AML)
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<p>Effect of FLT3 inhibition on DC differentiation and surface expression of costimulatory molecules. DCs generated from murine bone marrow cells were differentiated in the presence of 100 nM gilteritinib, midostaurin or quizartinib and were gated using forward and sideward scatter. Dead cells were excluded by life/dead staining. Proportion of double-positive CD11c+/CD11b+ cells is markedly reduced after differentiation in the presence of midostaurin (<b>a</b>). Human PBMCs were cultured to obtain DCs as described. Midostaurin-induced monocyte differentiation indicated by reduced CD1a and increased CD14 expression in the presence of midostaurin (<span class="html-italic">p</span> &lt; 0.0001) and gilteritinib (<span class="html-italic">p</span> &lt; 0.05) (<b>b</b>). Differentiation of murine bone marrow cells in the presence of midostaurin (M1 = 1 nM; M10 = 10 nM; M100 = 100 nM), gilteritinib (G1 = 1 nM; G10 = 10 nM; G100 = 100 nM) or quizartinib (Q1 = 1 nM; Q10 = 10 nM; Q100 = 100 nM) in different concentrations did not induce apoptosis (<b>c</b>). The mean fluorescence intensity of CD40 and CD86 on bmDCs after LPS stimulation was reduced in a dose-dependent manner by midostaurin (<span class="html-italic">p</span> &lt; 0.0001) and gilteritinib (<span class="html-italic">p</span> &lt; 0.05) exposure (<b>d</b>). MoDCs showed reduced CD80, CD83 and CD86 expression after midostaurin treatment with 100 nM. The effect was less pronounced after gilteritinib (100 nM) and only minimal after quizartinib (100 nM) treatment. MFI and rates of positive cells are depicted in the right upper corner (<b>e</b>). ns not significant, * <span class="html-italic">p</span> &lt; 0.05, **** = <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>FTL3 inhibition suppresses cytokine secretion by dendritic cells. After 6 days of differentiation in the presence of FLT3i at 100 nM concentration, cytokine release of bmDCs was measured 18 h after LPS stimulation. IL-12 levels were only reduced after midostaurin treatment (<span class="html-italic">p</span> &lt; 0.01), while IL-6 (<span class="html-italic">p</span> &lt; 0.01 for midostaurin and <span class="html-italic">p</span> &lt; 0.001 for gilteritinib) and CCL-2 levels (<span class="html-italic">p</span> &lt; 0.0001 for both FLT3i) were also negatively affected by gilteritinib treatment. TNFα secretion was not affected. The generation of bmDCs is illustrated. Created with BioRender.com/j07f023 (<b>a</b>). For moDCs, midostaurin (100 nM) and gilteritinib (100 nM) treatment reduces TNFα (<span class="html-italic">p</span> &lt; 0.0001), IL-6 (<span class="html-italic">p</span> &lt; 0.01) and IL-12 levels (<span class="html-italic">p</span> &lt; 0.0001), quizartinib (100 nM) treatment did not affect TNFα levels but lowered IL-12 (<span class="html-italic">p</span> &lt; 0.01) and IL-6 (<span class="html-italic">p</span> &lt; 0.05) levels. Schematic illustration of moDC generation created with BioRender.com/u60g276 (<b>b</b>). ns not significant, * = <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, **** = <span class="html-italic">p</span> &lt; 0.0001.</p>
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<p>RNA sequencing reveals inhibition of important immune response pathways by FLT3i, which is supported by protein expression analysis. BmDCs were cultured in the presence of DMSO or FLT3i. After 6 days, cells were stimulated with LPS, when indicated, and RNA was harvested 18 h later. Using hierarchical clustering, the top 20 differentially expressed genes found in RNA sequencing analysis reveal specific clustering of DMSO control samples and after exposure to midostaurin but not for other treatment groups. Expression values are depicted from low (blue) to high (red) (<b>a</b>). Concomitantly, principal component analysis (PCA) based on all analyzed gene sets also showed high similarity of midaustaurin-treated samples (<b>b</b>). Log-fold change in gene expression of midostaurin-, gilteritinib- and quizartinib-treated moDCs after LPS maturation is depicted in a heatmap. Up- (blue) and downregulation (red) are color-coded (<b>c</b>). To prove the inhibition of relevant pathways, protein was extracted from human moDCs after FLT3i treatment and LPS stimulation. Stat3 and Stat5 phosphorylation was impaired by midostaurin treatment (<b>d</b>). Inhibition of Akt phosphorylation was observed after midostaurin and quizartinib treatment (<b>e</b>). The NFκB pathway was inhibited by midostaurin and gilteritinib treatment as cRel and relB expression were reduced. Quizartinib did not affect relB or cRel expression (<b>f</b>). The uncropped bolts are shown in <a href="#app1-cancers-16-03719" class="html-app">Supplementary Materials</a>.</p>
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10 pages, 1591 KiB  
Article
Luteolin (LUT) Induces Apoptosis and Regulates Mitochondrial Membrane Potential to Inhibit Cell Growth in Human Cervical Epidermoid Carcinoma Cells (Ca Ski)
by Sung-Nan Pei, Kuan-Ting Lee, Kun-Ming Rau, Tsung-Ying Lin, Tai-Hsin Tsai and Yi-Chiang Hsu
Biomedicines 2024, 12(10), 2330; https://doi.org/10.3390/biomedicines12102330 - 14 Oct 2024
Viewed by 788
Abstract
Background/Objectives: Luteolin (LUT) is a natural flavonoid with known anti-inflammatory, antioxidant, and anti-cancer properties. Cervical cancer, particularly prevalent in certain regions, remains a significant health challenge due to its high recurrence and poor response to treatment. This study aimed to investigate the anti-tumor [...] Read more.
Background/Objectives: Luteolin (LUT) is a natural flavonoid with known anti-inflammatory, antioxidant, and anti-cancer properties. Cervical cancer, particularly prevalent in certain regions, remains a significant health challenge due to its high recurrence and poor response to treatment. This study aimed to investigate the anti-tumor effects of LUT on human cervical epidermoid carcinoma cells (Ca Ski), focusing on cell growth inhibition, apoptosis induction, and regulation of mitochondrial membrane potential. Methods: Ca Ski cells were treated with varying concentrations of LUT (0, 25, 50, 100 µM) for different time periods (24, 48, 72 hours). Cell viability was measured using the MTT assay, apoptosis was assessed by flow cytometry with annexin V-FITC/PI staining, and changes in mitochondrial membrane potential were evaluated using JC-1 staining. Caspase-3 activation was examined by flow cytometry, and expression of apoptosis-related proteins (caspase-3, -8, -9, AIF) was analyzed via Western blotting. Results: LUT significantly inhibited the growth of Ca Ski cells in a dose- and time-dependent manner, with the most pronounced effects observed at 100 µM over 72 hours. Flow cytometry confirmed that LUT induced apoptosis without causing necrosis. Mitochondrial membrane potential was reduced after LUT treatment, coinciding with increased caspase-3 activation. Western blot analysis revealed the upregulation of pro-apoptotic proteins caspase-3, -8, -9, and AIF, indicating that LUT induces apoptosis through the intrinsic mitochondrial pathway. Conclusions: Luteolin effectively inhibits cervical cancer cell proliferation and induces apoptosis by disrupting mitochondrial membrane potential and activating caspases. These findings suggest that LUT holds potential as a therapeutic agent for cervical cancer, with further studies needed to explore its in vivo efficacy and broader clinical applications. Full article
(This article belongs to the Section Cell Biology and Pathology)
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<p>LUT affects the survival of cervical cancer cells (Ca Ski) and inhibits their proliferation. Ca Ski cells were treated with varying concentrations of LUT (0, 25, 50, and 100 µM) for 24 to 72 h, and cell viability was measured using the MTT assay. Results are presented as a percentage relative to the control, which is set at 100%. Data are expressed as the mean ± SEM from at least three experiments. Statistical significance was determined using a <span class="html-italic">t</span>-test, with * <span class="html-italic">p</span> &lt; 0.05 indicating a significant difference from the control group, # <span class="html-italic">p</span> &lt; 0.05 indicating a significant difference from the 24 h group, and &amp; <span class="html-italic">p</span> &lt; 0.05 indicating a significant difference from the 48 hrs group.</p>
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<p>The role of LUT in inducing cell apoptosis in cervical cancer cells (Ca Ski). (<b>A</b>) The extent of total apoptosis and necrosis in Ca Ski cells after 4 h of incubation with LUT. (<b>B</b>) Results are presented as a percentage relative to the control group, including necrosis and the total number of apoptotic cells (both early and late apoptosis). Statistical significance was assessed using a <span class="html-italic">t</span>-test, with * <span class="html-italic">p</span> &lt; 0.05 indicating a significant difference compared to the control group.</p>
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<p>Influence of LUT on cell cycle progression/distribution in cervical cancer cells. (<b>A</b>) Cell cycle analysis of Ca Ski cells after 24 h of treatment with LUT. (<b>B</b>) LUT treatment led to an increase in the percentage of cells in the sub-G1 phase. Results are presented as the mean ± SD from three experiments. The asterisk (*) in each bar group indicates that the difference compared to the 0 µM LUT treatment is statistically significant at <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>The effect of LUT on caspase 3 activation and mitochondrial membrane potential. (<b>A</b>) LUT-induced changes in mitochondrial membrane potential (ΔΨm) were assessed in Ca Ski cells. ΔΨm levels were determined using JC-1 staining and flow cytometry. (<b>B</b>) Cells were treated with varying concentrations of LUT for 24 h. Statistical significance is indicated by * <span class="html-italic">p</span> &lt; 0.05. (<b>C</b>) Following 24 h treatment with LUT, cells were harvested and labeled with FITC-conjugated anti-active caspase 3 antibody. (<b>D</b>) Caspase 3 activation was quantified by flow cytometry. All data are expressed as mean ± SD from three independent experiments, with statistical significance denoted by * <span class="html-italic">p</span> &lt; 0.05.</p>
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<p>The expression of LUT-regulated caspase family in Ca Ski cells. (<b>A</b>) The expression of pro-caspase 3, 8, 9, and AIF were assessed by Western blot analysis in Ca Ski cells. (<b>B</b>) The quantification of pro-caspase 3, 8, 9, and AIF is shown in the bar graph. Data were normalized to GAPDH as a control and expressed as a percentage relative to the control group, which was set at 100%. All results are presented as the mean (±SEM) of at least three independent experiments. Statistical significance was determined using a <span class="html-italic">t</span>-test, with * <span class="html-italic">p</span> &lt; 0.05 indicating significant differences compared to the control group.</p>
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14 pages, 1995 KiB  
Article
Cardioprotection by Preconditioning with Intralipid Is Sustained in a Model of Endothelial Dysfunction for Isolated-Perfused Hearts
by Martin Stroethoff, Natalie Schneider, Lea Sung, Jan Wübbolt, André Heinen and Annika Raupach
Int. J. Mol. Sci. 2024, 25(20), 10975; https://doi.org/10.3390/ijms252010975 - 12 Oct 2024
Viewed by 794
Abstract
Endothelial dysfunction (ED) is closely associated with most cardiovascular diseases. Experimental models are needed to analyze the potential impact of ED on cardioprotection in constant pressure Langendorff systems (CPLS). One cardioprotective strategy against ischemia/reperfusion injury (I/RI) is conditioning with the lipid emulsion Intralipid [...] Read more.
Endothelial dysfunction (ED) is closely associated with most cardiovascular diseases. Experimental models are needed to analyze the potential impact of ED on cardioprotection in constant pressure Langendorff systems (CPLS). One cardioprotective strategy against ischemia/reperfusion injury (I/RI) is conditioning with the lipid emulsion Intralipid (IL). Whether ED modulates the cardioprotective effect of IL remains unknown. The aim of the study was to transfer a protocol using a constant flow Langendorff system for the induction of ED into a CPLS, without the loss of smooth muscle cell functionality, and to analyze the cardioprotective effect of IL against I/RI under ED. In isolated hearts of male Wistar rats, ED was induced by 10 min perfusion of a Krebs–Henseleit buffer containing 60 mM KCl (K+), and the vasodilatory response to the vasodilators histamine (endothelial-dependent) and sodium–nitroprusside (SNP, endothelial-independent) was measured. A CPLS was employed to determine cardioprotection of pre- or postconditioning with 1% IL against I/RI. The constant flow perfusion of K+ reduced endothelial response to histamine but not to SNP, indicating reduced vasodilatory functionality of endothelial cells but not smooth muscle cells. Preconditioning with IL reduced infarct size and improved cardiac function while postconditioning with IL had no effect. The induction of ED neither influenced infarct size nor affected the cardioprotective effect by preconditioning with IL. This protocol allows for studies of cardioprotective strategies under ED in CLPS. The protection by preconditioning with IL seems to be mediated independently of a functional endothelium. Full article
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<p>Difference of endothelial response (ΔER = ER<sub>1</sub> − ER<sub>2</sub>) before (ER<sub>1</sub>) and after (ER<sub>2</sub>) constant flow perfusion (10 min) with Krebs–Henseleit buffer (KHB) alone (white fill) or KHB containing 60 mM KCl (K+, striped green) to 800 nmol histamine (his, orange borders) or 1 µM sodium nitroprusside (SNP, pink borders). As a positive control for ED induction, a bolus of 1 s with 1% triton (grey fill) was used. Data are mean ± SD, <span class="html-italic">n</span> = 4 (SNP, triton), <span class="html-italic">n</span> = 7 (histamine). One-way ANOVA followed by Šidák’s multiple comparison test. *: <span class="html-italic">p</span> &lt; 0.05, ns: not significant (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Infarct sizes of hearts after ischemia/reperfusion with pre- or post-treatment for 10 min with 1% Intralipid (IL) or vehicle (Con). LV: left ventricle. Data are mean ± SD, <span class="html-italic">n</span> = 7. One-way ANOVA, Dunnett’s multiple comparison test, *: <span class="html-italic">p</span> &lt; 0.05, ns: not significant (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Infarct sizes of hearts after ischemia/reperfusion with post-treatment for 20 min with Intralipid (IL) or vehicle (Con). LV: left ventricle. Data are mean ± SD, <span class="html-italic">n</span> = 6. <span class="html-italic">t</span>-test; ns: not significant.</p>
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<p>Preconditioning with IL under endothelial dysfunction (ED). Hearts were treated for 10 min before ischemia with 1% Intralipid (IL; blue border) or vehicle (Con; black border). ED was induced by 10 min constant flow perfusion of Krebs–Henseleit buffer (KHB) containing 60 mM KCl (K+; green stripes). The other groups received normal KHB under constant flow conditions (white filling). LV: left ventricle. Data are mean ± SD, <span class="html-italic">n</span> = 7. Two-way ANOVA; * <span class="html-italic">p</span> &lt; 0.05 for effect by conditioning; ns = not significant for effect by ED induction and interaction (<span class="html-italic">p</span> &gt; 0.05).</p>
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<p>Schematic drawing of the utilized Langendorff system. Krebs–Henseleit buffer (KHB) and KHB containing 1% Intralipid (IL) are perfused in a constant pressure mode (80 mmHg) in separate circuits. To induce endothelial dysfunction, KHB containing 60 mM KCl (K+) is perfused in a constant flow mode. To ensure equivalent control conditions for induction of ED, KHB is perfused in a constant flow mode. The individual modules were switched on or off as required by the respective questions during the experimental setups. Created with <a href="http://BioRender.com" target="_blank">BioRender.com</a>.</p>
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<p>Experimental timeline for characterization of endothelial dysfunction. Dashed blue lines mark measuring points for coronary perfusion pressure (CPP). BL1/2: baseline at time point 1/2, P: after perfusion of vasodilator, His: histamine, T: triton, SNP: sodium–nitroprusside, KHB flow: constant flow perfusion with Krebs–Henseleit buffer, K+ flow: constant flow perfusion with KHB containing 60 mM KCl.</p>
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<p>Experimental protocol: conditioning with Intralipid (IL) using a constant pressure Langendorff system with the ability to switch into a constant flow mode for induction of endothelial dysfunction. (<b>a</b>) Pre- or postconditioning with IL for 10 min. (<b>b</b>) Postconditioning with IL for 20 min. (<b>c</b>) Preconditioning with IL under endothelial dysfunction induced by constant flow perfusion of Krebs–Henseleit buffer (KHB) containing 60 mM KCl (K+ flow) and under control condition with constant flow perfusion of KHB alone (KHB flow).</p>
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20 pages, 6767 KiB  
Article
Highly Accurate Deep Learning Models for Estimating Traffic Characteristics from Video Data
by Bowen Cai, Yuxiang Feng, Xuesong Wang and Mohammed Quddus
Appl. Sci. 2024, 14(19), 8664; https://doi.org/10.3390/app14198664 - 26 Sep 2024
Viewed by 985
Abstract
Traditionally, traffic characteristics such as speed, volume, and travel time are obtained from a range of sensors and systems such as inductive loop detectors (ILDs), automatic number plate recognition cameras (ANPR), and GPS-equipped floating cars. However, many issues associated with these data have [...] Read more.
Traditionally, traffic characteristics such as speed, volume, and travel time are obtained from a range of sensors and systems such as inductive loop detectors (ILDs), automatic number plate recognition cameras (ANPR), and GPS-equipped floating cars. However, many issues associated with these data have been identified in the existing literature. Although roadside surveillance cameras cover most road segments, especially on freeways, existing techniques to extract traffic data (e.g., speed measurements of individual vehicles) from video are not accurate enough to be employed in a proactive traffic management system. Therefore, this paper aims to develop a technique for estimating traffic data from video captured by surveillance cameras. This paper then develops a deep learning-based video processing algorithm for detecting, tracking, and predicting highly disaggregated vehicle-based data, such as trajectories and speed, and transforms such data into aggregated traffic characteristics such as speed variance, average speed, and flow. By taking traffic observations from a high-quality LiDAR sensor as ‘ground truth’, the results indicate that the developed technique estimates lane-based traffic volume with an accuracy of 97%. With the application of the deep learning model, the computer vision technique can estimate individual vehicle-based speed calculations with an accuracy of 90–95% for different angles when the objects are within 50 m of the camera. The developed algorithm was then utilised to obtain dynamic traffic characteristics from a freeway in southern China and employed in a statistical model to predict monthly crashes. Full article
(This article belongs to the Special Issue Applications of Artificial Intelligence in Transportation Engineering)
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<p>Flowchart of detection logic.</p>
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<p>Modified FairMOT (mFairMOT) network structure (CBL: block for convolution+batch normalisation+Leaky_Relu; Res Unit: residual block unit; Leaky Relu: an activation function; BN: batch normalisation; CSP: cross-stage partial network; SPP: spatial pyramid pooling).</p>
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<p>Road marker label (ABCD are anchor pointes and W represents the width of the rectangle).</p>
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<p>Virtual box and shadow area movements when a vehicle passes.</p>
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<p>Representative scenario used for speed detection (straight lines denote detection region).</p>
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<p>Representative scenario used for speed detection (straight lines denote detection region).</p>
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<p>Abnormal parking detection (straight lines denote detection region).</p>
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<p>Person on freeway detection.</p>
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<p>Traffic congestion detection.</p>
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<p>Detection of vehicle fire (blue: fire, red: smoke).</p>
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15 pages, 5098 KiB  
Article
Distribution System State Estimation Based on Power Flow-Guided GraphSAGE
by Baitong Zhai, Dongsheng Yang, Bowen Zhou and Guangdi Li
Energies 2024, 17(17), 4317; https://doi.org/10.3390/en17174317 - 28 Aug 2024
Viewed by 721
Abstract
Acquiring real-time status information of the distribution system forms the foundation for optimizing the management of power system operations. However, missing measurements, bad data, and inaccurate system models present a formidable challenge for distribution system state estimation (DSSE) in practical applications. This paper [...] Read more.
Acquiring real-time status information of the distribution system forms the foundation for optimizing the management of power system operations. However, missing measurements, bad data, and inaccurate system models present a formidable challenge for distribution system state estimation (DSSE) in practical applications. This paper proposes a physics-informed graphical learning state estimation approach, to address these limitations by integrating power flow equations and GraphSAGE. The generalization ability of GraphSAGE for unknown nodes is used to perform inductive learning of measurement information. For unseen measurement points in the training set, the simulation proves that the proposed approach can still satisfactorily predict the state quantity. The training process is guided by power flow equations to ensure it has physical significance. Additionally, the possibility of applying the proposed approach to an actual distribution area is explored. Equivalent preprocessing of the three-phase voltage measurement data of the actual distribution area is conducted to improve the estimation accuracy of the transformer measurement points and simplify the computation required for state estimation. Full article
(This article belongs to the Special Issue Optimizing Power Quality in Smart Grid Systems)
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<p>Weighted least squares method.</p>
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<p>A visual illustration of the GraphSAGE approach.</p>
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<p>Proposed PF-GraphSAGE approach.</p>
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<p>Distribution transformer equivalent circuit.</p>
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<p>An actual distribution area in northeastern China.</p>
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<p>The equivalent voltage of a three-phase transformer.</p>
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<p>Visualization of three test systems. (<b>a</b>) IEEE14 14-bus system, (<b>b</b>) IEEE33 33-bus system, (<b>c</b>) CNEDA404 404-bus system.</p>
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<p>Validation RMSE of voltage during training.</p>
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<p>Voltage level estimates at (<b>a</b>) bus 4 and (<b>b</b>) bus 26 of the IEEE33 dataset under normal conditions.</p>
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<p>Comparing RMSE of estimating voltage in the IEEE14 dataset between PF-GraphSAGE, WLS, and LAV.</p>
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<p>Voltage level estimates at (<b>a</b>) bus 35 and (<b>b</b>) bus 248 of CNEDA404 under normal conditions.</p>
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<p>Voltage level estimates at (<b>a</b>) bus 35 and (<b>b</b>) bus 248 of CNEDA404 under normal conditions.</p>
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<p>Voltage level estimates at (<b>a</b>) bus 83, (<b>b</b>) bus 107, and (<b>c</b>) bus 293 of CNEDA404, with the changes in topology over time.</p>
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19 pages, 4594 KiB  
Article
Resveratrol Mitigates Cognitive Impairments and Cholinergic Cell Loss in the Medial Septum in a Mouse Model of Gradual Cerebral Hypoperfusion
by Eric Fagerli, Charles W. Jackson, Iris Escobar, Fernando J. Ferrier, Efrain J. Perez Lao, Isabel Saul, Jorge Gomez, Kunjan R. Dave, Oliver Bracko and Miguel A. Perez-Pinzon
Antioxidants 2024, 13(8), 984; https://doi.org/10.3390/antiox13080984 - 14 Aug 2024
Viewed by 1091
Abstract
Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia. There is currently no effective treatment for VCID. Resveratrol (RSV) is considered an antioxidant; however, our group has observed pleiotropic effects in stroke paradigms, suggesting more effects may contribute to [...] Read more.
Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia. There is currently no effective treatment for VCID. Resveratrol (RSV) is considered an antioxidant; however, our group has observed pleiotropic effects in stroke paradigms, suggesting more effects may contribute to mechanistic changes beyond antioxidative properties. The main goal of this study was to investigate if administering RSV twice a week could alleviate cognitive declines following the induction of a VCID model. Additionally, our aim was to further describe whether this treatment regimen could decrease cell death in brain areas vulnerable to changes in cerebral blood flow, such as the hippocampus and medial septum. We hypothesized RSV treatments in a mouse model of gradual cerebral hypoperfusion protect against cognitive impairment. We utilized gradual bilateral common carotid artery stenosis (GBCCAS) via the surgical implantation of ameroid constrictor devices. RSV treatment was administered on the day of implantation and twice a week thereafter. Cerebral perfusion was measured by laser speckle contrast imaging, and cognitive functions, including the recognition memory, the spatial working memory, and associative learning, were assessed by novel object recognition (NOR), Y-maze testing, and contextual fear conditioning (CFC), respectively. RSV treatment did not alleviate cerebral perfusion deficits but mitigated cognitive deficits in CFC and NOR after GBCCAS. Despite these deficits, no hippocampal pathology was observed; however, cholinergic cell loss in the medial septum was significantly increased after GBCCAS. This cholinergic cell loss was mitigated by RSV. This study describes a novel mechanism by which chronic RSV treatments protect against a VCID-induced cognitive decline through the preservation of cholinergic cell viability to improve memory performance. Full article
(This article belongs to the Special Issue Oxidative Stress and Pathophysiology of Stroke)
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<p>Experimental schematic for in vivo RSV treatments, LSCI measurements, and behavioral tests. LSCI was performed the day prior to AC or sham surgery and then 1, 14, and 33 days following surgery. RSV was administered on the day that the surgery occurred as well as twice per week thereafter, as indicated by the arrows. Behavioral testing occurred on days 27 through 32 following the surgery and consisted of open-field testing (OFT), two days of novel object recognition testing (NORT), Y-maze testing, and two days of contextual fear conditioning (CFC) testing. Arrows indicate days of RSV administration.</p>
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<p>Resveratrol does not ameliorate deficits in cerebral blood flow in the VCID model. (<b>A</b>) Representative LSCI images in the four treatment groups. (<b>B</b>) Relative cerebral perfusion rates for all groups relative to baseline. Data are expressed as mean ± SEM. n = 8 for each of the VCID groups and 11 for each of the sham groups. dp = days post-surgery. # indicates significance between the VCID + Veh group compared to the Sham + Veh group, while @ indicates significance between the VCID + RSV and Sham + RSV groups. # and @ <span class="html-italic">p</span> &lt; 0.05. ## and @@ <span class="html-italic">p</span> &lt; 0.01. ### and @@@ <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>General activity/locomotor function, anxiety-related behavior, and spontaneous alternation via Y-maze testing are not affected by VCID. An analysis was performed on (<b>A</b>) the distance traveled, (<b>B</b>) the time spent in the center of the open field, which was found among the groups, and (<b>C</b>) spontaneous alternations in Y-maze testing, which were found. Data are expressed as a mean ± SEM. n = 8 for each of the VCID groups and 11 for each of the sham groups.</p>
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<p>General activity/locomotor function, anxiety-related behavior, and spontaneous alternation via Y-maze testing are not affected by VCID. An analysis was performed on (<b>A</b>) the distance traveled, (<b>B</b>) the time spent in the center of the open field, which was found among the groups, and (<b>C</b>) spontaneous alternations in Y-maze testing, which were found. Data are expressed as a mean ± SEM. n = 8 for each of the VCID groups and 11 for each of the sham groups.</p>
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<p>Impairments in object recognition memory and contextual fear memory caused by VCID were reduced by resveratrol treatments. (<b>A</b>) VCID-induced impairment in recognition memory, which was ameliorated via resveratrol treatments. (<b>B</b>) VCID-induced impairment in contextual fear memory, which was prevented by resveratrol treatments. Data are expressed as a mean ± SEM. n = 8 for each of the VCID groups and 11 for each of the sham groups. * <span class="html-italic">p</span> &lt; 0.05. ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>The hippocampal neuronal count in the CA1 pyramidal layer was unaffected by the VCID model, as shown in (<b>A</b>) the representative images and the (<b>B</b>) the quantification of the CA1 pyramidal layer. Scale bar = 200 μm (main image) or 100 μm (inset image). Data are expressed as a mean ± SEM. n = 8 for each of the VCID groups and 9 for each of the sham groups.</p>
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<p>Resveratrol mitigates medial septal cholinergic neuronal loss following 33 days of VCID. (<b>A</b>) Maximum intensity projection images showing expression of ChAT-positive neurons (yellow) in the medial septum at Bregma +0.88 mm. (<b>B</b>) Quantified number of ChAT-positive cells in the full medial septum. Scale bar = 200 μm (main image) or 100 μm (inset image). Data are expressed as a mean ± SEM. n = 8 for each of the VCID groups and 9 for each of the sham groups. * <span class="html-italic">p</span> &lt; 0.05. ** <span class="html-italic">p</span> &lt; 0.01.</p>
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12 pages, 2161 KiB  
Article
[15O]H2O PET/MRI for Assessment of Complete Response to Neoadjuvant or Induction Chemotherapy in Patients with Muscle-Invasive Bladder Cancer: A Pilot Study
by Stefanie Korsgaard Körner, Lars Poulsen Tolbod, Bodil G. Pedersen, Thierry Boellaard, Rikke Vilsbøll Milling, Simone Buchardt Brandt, Mads Agerbæk, Lars Dyrskjøt, Kirsten Bouchelouche and Jørgen B. Jensen
J. Clin. Med. 2024, 13(16), 4652; https://doi.org/10.3390/jcm13164652 - 8 Aug 2024
Viewed by 882
Abstract
Background: Accurate assessment of therapy response to chemotherapy could possibly offer a bladder-sparing approach in selected patients with localized muscle-invasive bladder cancer (MIBC). The aim of this study was to evaluate whether [15O]H2O PET/MRI can be used for assessment [...] Read more.
Background: Accurate assessment of therapy response to chemotherapy could possibly offer a bladder-sparing approach in selected patients with localized muscle-invasive bladder cancer (MIBC). The aim of this study was to evaluate whether [15O]H2O PET/MRI can be used for assessment of complete local pathological response to preoperative chemotherapy in patients with MIBC. Methods: This prospective pilot study included 13 patients with MIBC treated with neoadjuvant or induction chemotherapy and subsequent radical cystectomy. Patients underwent a [15O]H2O PET/MRI scan before chemotherapy and another scan after chemotherapy before radical cystectomy. Volumes of interest were delineated on T2-weighted MRI and transferred to parametric images for dynamic analysis. Tumor blood flow (TBF) was estimated by [15O]H2O PET. Changes in TBF were compared with histopathology. The Wilcoxon matched-pairs signed-ranks test was used for comparing pre- and post-chemotherapy measurements. Results: Mean TBF decreased by 49%. Mean TBF in complete responders (ypT0N0/ypTis) was not significantly different from non-complete responders (≥ypT1) (p = 0.52). Conclusions: Despite a measurable decrease in TBF after chemotherapy treatment, we were not able to estimate a TBF threshold for identifying complete responders to chemotherapy for MIBC patients. Further studies are needed to elucidate the potential of [15O]H2O PET/MRI in assessing therapy response in MIBC. Full article
(This article belongs to the Special Issue Treatment of Bladder Cancer: From Past to Future)
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<p>Timeline of study. TURBT = transurethral resection of bladder tumor; NAIC = neoadjuvant or induction chemotherapy. Created in biorender.com.</p>
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<p>T2-weighted (T2w) MRI and [<sup>15</sup>O]H<sub>2</sub>O PET parametric images (K<sub>1</sub> and k<sub>2</sub>) pre- and post-chemotherapy of three study patients. ID 4 had wall thickening on T2w MRI but decreased tumor blood flow (TBF) post-chemotherapy and had ypT1b + Tis. ID 5 had no visible tumor and decreased TBF post-chemotherapy and had ypT0. ID 11 had suspect volume of interest but decreased TBF post-chemotherapy, and patient had ypT0.</p>
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<p>T2-weighted (T2w) MRI and [<sup>15</sup>O]H<sub>2</sub>O PET parametric images (K<sub>1</sub> and k<sub>2</sub>) pre- and post-chemotherapy of three study patients. ID 4 had wall thickening on T2w MRI but decreased tumor blood flow (TBF) post-chemotherapy and had ypT1b + Tis. ID 5 had no visible tumor and decreased TBF post-chemotherapy and had ypT0. ID 11 had suspect volume of interest but decreased TBF post-chemotherapy, and patient had ypT0.</p>
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<p>Flowchart of inclusion.</p>
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<p>Percentage change in tumor volume from pre-chemotherapy to post-chemotherapy MRI.</p>
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<p>Tumor blood flow and perfusable tissue fraction pre- and post-chemotherapy. (<b>A</b>) Tumor blood flow. (<b>B</b>) Perfusable tissue fraction.</p>
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25 pages, 6867 KiB  
Article
Derivation of Analytical Expressions for Fast Calculation of Resistance Spot Welding System Currents
by Robert Brezovnik and Jožef Ritonja
Mathematics 2024, 12(16), 2454; https://doi.org/10.3390/math12162454 - 7 Aug 2024
Viewed by 683
Abstract
The paper deals with the dynamics of a resistance spot welding system. At the core of this system is a transformer, which is powered on the primary side by a pulse-width modulated inverter and has a full-wave output rectifier on the secondary side [...] Read more.
The paper deals with the dynamics of a resistance spot welding system. At the core of this system is a transformer, which is powered on the primary side by a pulse-width modulated inverter and has a full-wave output rectifier on the secondary side that provides a direct welding current. The entire system is nonlinear, due to magnetic hysteresis and electronics. The electronics prevent the current from flowing in all parts of the welding transformer at separate time intervals during the voltage supply period; therefore, not all the parameters affect the dynamic of currents and voltages all the time so the system is also time-variant. To design a high-performance welding system and to predict the maximum possible welding current at a specific load, it is necessary to know the welding and primary currents. The leakage inductances of the system can reduce the maximum welding current significantly at higher frequencies and the same load. There are several methods to determine these currents, each with its drawbacks. Measurements are time-consuming, using professional software is expensive and requires time to learn and free open-source software has many limitations and does not guarantee the correctness of the results. The article presents a new, fourth option—a theoretical derivation of analytical expressions that facilitate straightforward and rapid calculation of the welding and primary currents of the resistance spot welding system with symmetrical secondary branches. The derivation of the mathematical expressions is based on the equivalent circuits that describe the system in different operating states. The results of the numerical simulations confirmed the derived expressions completely. Full article
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<p>Nonlinear core saturation function.</p>
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<p>Schematic presentation of the analyzed RSW system.</p>
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<p>Extended circuit model of the RSW system.</p>
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<p>Time series of (<b>a</b>) transistor control voltage <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>u</mi> </mrow> <mrow> <mi>T</mi> <mo>+</mo> </mrow> </msub> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>u</mi> </mrow> <mrow> <mi>T</mi> <mo>−</mo> </mrow> </msub> </mrow> </semantics></math>, (<b>b</b>) H-bridge voltage <math display="inline"><semantics> <mrow> <mi>u</mi> </mrow> </semantics></math>.</p>
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<p>The Matlab/Simulink model of the RSW system.</p>
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<p>Time series for 20 periods of (<b>a</b>) H-bridge voltage <math display="inline"><semantics> <mrow> <mi>u</mi> </mrow> </semantics></math>, (<b>b</b>) welding current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and both secondary currents (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>1</mn> </mrow> </msub> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>2</mn> </mrow> </msub> </mrow> </semantics></math>), and (<b>c</b>) primary current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>Time series for one period of (<b>a</b>) H-bridge voltage <math display="inline"><semantics> <mrow> <mi>u</mi> </mrow> </semantics></math>, (<b>b</b>) welding current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and both secondary currents (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>1</mn> </mrow> </msub> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>2</mn> </mrow> </msub> </mrow> </semantics></math>), and (<b>c</b>) primary current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>One and a half period of (<b>a</b>) transistor control voltage <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>u</mi> </mrow> <mrow> <mi>T</mi> <mo>+</mo> </mrow> </msub> </mrow> </semantics></math> and <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>u</mi> </mrow> <mrow> <mi>T</mi> <mo>−</mo> </mrow> </msub> </mrow> </semantics></math>, (<b>b</b>) H-bridge voltage <math display="inline"><semantics> <mrow> <mi>u</mi> </mrow> </semantics></math>, (<b>c</b>) welding current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and both secondary currents (<math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>1</mn> </mrow> </msub> </mrow> </semantics></math>, <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>s</mi> <mn>2</mn> </mrow> </msub> </mrow> </semantics></math>), and (<b>d</b>) primary current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>Simplified equivalent circuit with only one secondary branch.</p>
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<p>Equivalent circuit model defining the fast-changing primary current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>Equivalent circuit model defining decreasing welding current <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>The comparison of analytically and numerically (Simulink) calculated (<b>a</b>) welding <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and (<b>b</b>) primary currents <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math>.</p>
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<p>The difference between the analytically and numerically (Simulink) calculated (<b>a</b>) welding, and (<b>b</b>) primary currents.</p>
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<p>The comparison of analytically and numerically (Simulink) calculated (<b>a</b>) welding <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and (<b>b</b>) primary currents <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math> at the minimal duty cycle <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>D</mi> </mrow> <mrow> <mi>m</mi> <mi>i</mi> <mi>n</mi> </mrow> </msub> <mo>=</mo> <mn>0.06889</mn> </mrow> </semantics></math>.</p>
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<p>The comparison of analytically and numerically (Simulink) calculated (<b>a</b>) welding <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>w</mi> </mrow> </msub> </mrow> </semantics></math> and (<b>b</b>) primary currents <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>i</mi> </mrow> <mrow> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math> at the maximal duty cycle <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>D</mi> </mrow> <mrow> <mi>m</mi> <mi>a</mi> <mi>x</mi> </mrow> </msub> <mo>=</mo> <mn>0.9619</mn> </mrow> </semantics></math>. Due to minimal differences, the red time series (Simulink) overlaps the blue time series (Analytical).</p>
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14 pages, 1795 KiB  
Article
Immunogenicity of an Inactivated Senecavirus A Vaccine with a Contemporary Brazilian Strain in Mice
by Amanda de Oliveira Barbosa, Danielle Gava, Caroline Tochetto, Leonardo Clasen Ribeiro, Ana Paula Almeida Bastos, Marcos Antônio Zanella Morés, Rejane Schaefer and Marcelo de Lima
Vaccines 2024, 12(8), 845; https://doi.org/10.3390/vaccines12080845 - 26 Jul 2024
Viewed by 869
Abstract
Senecavirus A (SVA) is a picornavirus that is endemic in swine, causing a vesicular disease clinically indistinguishable from other vesicular diseases, like foot-and-mouth disease. The widespread viral circulation, constant evolution, and economic losses caused to the swine industry emphasize the need for measures [...] Read more.
Senecavirus A (SVA) is a picornavirus that is endemic in swine, causing a vesicular disease clinically indistinguishable from other vesicular diseases, like foot-and-mouth disease. The widespread viral circulation, constant evolution, and economic losses caused to the swine industry emphasize the need for measures to control the agent. In this study, we evaluated the immunogenicity of a whole-virus-inactivated vaccine using a representative contemporary Brazilian SVA strain in Balb/ByJ mice. The animals were vaccinated with two doses by an intramuscular route. The humoral response induced by the vaccination was evaluated by an in-house ELISA assay for IgG detection. The cellular response was assessed by flow cytometry after in vitro SVA stimulation in splenocyte cultures from vaccinated and non-vaccinated groups. Protection against SVA was assessed in the experimental groups following an oral challenge with the homologous virus. The vaccination induced high levels of IgG antibodies and the proliferation of CD45R/B220+sIgM+, CD3e+CD69+, and CD3e+CD4+CD44+CD62L cells. These results indicate the immunogenicity and safety of the vaccine formulation in a murine model and the induction of humoral and cellular response against SVA. Full article
(This article belongs to the Special Issue Porcine Vaccines: Enhancing Health, Productivity, and Welfare)
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<p>Experimental design. Timeline of GI (non-vaccinated and in vitro stimulated), GII (non-vaccinated and challenged), GIII (vaccinated and in vitro stimulated), and GIV (vaccinated and challenged) groups, highlighting the time points (Days 0, 15, 36, and 41) of blood and feces collection, administration of inactivated <span class="html-italic">Senecavirus A</span> vaccine (first and second doses) and euthanasia of mice. Illustration created with <a href="http://BioRender.com" target="_blank">BioRender.com</a> (accessed on 28 June 2024).</p>
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<p>Cq values of SVA RNA load by RT-PCR in pooled fecal samples collected from mice before (days 0–36) and after (days 37–41) the challenge for the four groups (GI—non-vaccinated, GII—non-vaccinated and challenged, GIII—vaccinated, and GIV—vaccinated and challenged).</p>
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<p>ELISA for detection of IgG against SVA at 0, 15, 36, and 41 dpv. The values are presented individually for each animal in its respective treatment group (GI—non-vaccinated; GII—non-vaccinated and challenged; GIII—vaccinated; GIV—vaccinated and challenged. The mean and ± standard deviation are represented by the black line ahead of the values. * <span class="html-italic">p</span> values ≤ 0.05 were considered statistically significant.</p>
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<p>In vitro stimulation assay. Immune cells in the splenocytes proliferation assay stimulated with the vaccine virus (SVA/BRA/GO/946-22/2019—8000 TCID<sub>50</sub>) were compared as a fold change from the vaccinated group (GIII) over the non-vaccinated group (GI) at 41 dpv. (<b>A</b>) T Lymphocyte Subset (CD3e<sup>+</sup>CD4<sup>+</sup>; CD3e<sup>+</sup>CD8α<sup>+</sup>); (<b>B</b>) T Lymphocyte Activation (CD3<sup>+</sup>CD69<sup>+</sup>; CD3<sup>+</sup>CD69<sup>+</sup>CD25<sup>+</sup>); (<b>C</b>) Naïve/Memory T cell (CD3<sup>+</sup>CD4<sup>+</sup>CD44<sup>+</sup>CD62L<sup>+</sup>; CD3<sup>+</sup>CD4<sup>+</sup>CD44<sup>+</sup>CD62L<sup>−</sup>); (<b>D</b>) B Lymphocyte Subset (CD45R/B220<sup>+</sup>IgM<sup>+</sup>; CD45R/B220<sup>+</sup>IgM<sup>+</sup>CD23<sup>+</sup>). Data shown are the fold increase in the mean and ± standard deviation represented by the black line ahead of the values. * <span class="html-italic">p</span> values ≤ 0.05 were considered statistically significant.</p>
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15 pages, 4483 KiB  
Article
Synthesis, Characterization, and Evaluation of a Hindered Phenol-Linked Benzophenone Hybrid Compound as a Potential Polymer Anti-Aging Agent
by Shenshuai Wang, Yingjie Huang, Weiye Sun and Xufeng Lin
Antioxidants 2024, 13(8), 894; https://doi.org/10.3390/antiox13080894 - 24 Jul 2024
Viewed by 962
Abstract
Hindered phenol antioxidants and benzophenone UV absorbers are common polymer additives and often used in combination applications to enhance the anti-aging performance of polymer materials. This study primarily aims to incorporate hindered phenol and benzophenone structures into a single molecule to develop a [...] Read more.
Hindered phenol antioxidants and benzophenone UV absorbers are common polymer additives and often used in combination applications to enhance the anti-aging performance of polymer materials. This study primarily aims to incorporate hindered phenol and benzophenone structures into a single molecule to develop a multifunctional polymer additive with good anti-aging performance. Thus, a novel potential polymer anti-aging agent, namely 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid 3-(4-benzoyl-3-hydroxyphenoxy)propyl ester (3C), was synthesized using 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid, 3-bromo-1-propanol, and 2,4-dihydroxybenzophenone as raw materials by two-step procedure. The structure of compound 3C was characterized by nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray single crystal diffraction. Its thermal stability and UV resistance were assessed using thermogravimetric analysis (TGA) and UV absorption spectroscopy (UV). The compound 3C as an additive was incorporated into the preparation of polyolefin elastomer (POE) films. The anti-aging performance of POE films was evaluated by measuring parameters such as oxidation induction time, melt flow index, transmittance, and infrared spectra of the artificially aged POE films. The results indicate that the compound 3C exhibits a promising anti-aging performance in both thermo-oxidative aging and ultraviolet aging tests of POE films and is a potential polymer anti-aging agent. Full article
(This article belongs to the Section Extraction and Industrial Applications of Antioxidants)
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<p>Synthesis of intermediate <b>A1</b>.</p>
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<p>Synthesis of <b>3C</b>.</p>
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<p>The X-ray single crystal diffraction pattern of compound <b>3C</b>.</p>
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<p>The UV absorption spectrum of compound <b>3C</b>.</p>
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<p>TGA test curve of compound <b>3C</b>.</p>
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<p>The DSC test curve of compound <b>3C</b>.</p>
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<p>Oxidative induction time of POE pellets after multiple extrusions.</p>
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<p>UV transmittance graphs of POE films.</p>
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<p>Light transmittance in POE films after thermal oxidative aging.</p>
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<p>Infrared spectrum of the POE film after thermal oxidative aging.</p>
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<p>Carbonyl index in POE films after thermal oxidative aging.</p>
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<p>Light transmittance in POE films after ultraviolet aging.</p>
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<p>Carbonyl index in POE films after ultraviolet aging.</p>
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<p><sup>1</sup>H NMR spectra of compound <b>A1</b>.</p>
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<p><sup>13</sup>C NMR spectra of compound <b>A1</b>.</p>
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<p><sup>1</sup>H NMR spectra of compound <b>3C</b>.</p>
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<p><sup>13</sup>C NMR spectra of compound <b>3C</b>.</p>
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10 pages, 3727 KiB  
Article
Two-Field Excitation for Contactless Inductive Flow Tomography
by Max Sieger, Katharina Gudat, Rahul Mitra, Stefanie Sonntag, Frank Stefani, Sven Eckert and Thomas Wondrak
Sensors 2024, 24(14), 4458; https://doi.org/10.3390/s24144458 - 10 Jul 2024
Cited by 1 | Viewed by 682
Abstract
Contactless inductive flow tomography (CIFT) is a flow measurement technique allowing for visualization of the global flow in electrically conducting fluids. The method is based on the principle of induction by motion: very weak induced magnetic fields arise from the fluid motion under [...] Read more.
Contactless inductive flow tomography (CIFT) is a flow measurement technique allowing for visualization of the global flow in electrically conducting fluids. The method is based on the principle of induction by motion: very weak induced magnetic fields arise from the fluid motion under the influence of a primary excitation magnetic field and can be measured precisely outside of the fluid volume. The structure of the causative flow field can be reconstructed from the induced magnetic field values by solving the according linear inverse problem using appropriate regularization methods. The concurrent use of more than one excitation magnetic field is necessary to fully reconstruct three-dimensional liquid metal flows. In our laboratory demonstrator experiment, we impose two excitation magnetic fields perpendicular to each other to a mechanically driven flow of the liquid metal alloy GaInSn. In the first approach, the excitation fields are multiplexed. Here, the temporal resolution of the measurement needs to be kept as high as possible. Consecutive application by multiplexing enables determining the flow structure in the liquid with a temporal resolution down to 3 s with the existing equipment. In another approach, we concurrently apply two sinusoidal excitation fields with different frequencies. The signals are disentangled on the basis of the lock-in principle, enabling a successful reconstruction of the liquid metal flow. Full article
(This article belongs to the Special Issue Tomographic and Multi-Dimensional Sensors)
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<p>Experimental set-up: (<b>a</b>) technical drawing with main components marked, (<b>b</b>) close-up of the dip tube with inlets and outlets and propeller (inset), and (<b>c</b>) visualization of the stationary flow structure determined by the inlets and outlets in a blended vector and streamline representation including sensor positions (grey boxes, one sensor that is evaluated in detail in following is marked in red).</p>
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<p>Photograph showing the liquid metal tank inside the two Helmholtz coil pairs for vertical and horizontal excitation magnetic fields.</p>
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<p>(<b>a</b>) General scheme of the consecutive CIFT two-field excitation (trapezoidal-shaped single profiles, total cycle length for both excitation fields 3 s, normalized amplitude). (<b>b</b>) Raw measurement data of induced magnetic field <b>b</b> for a total cycle length of 3 s for one exemplary sensor, marked red in <a href="#sensors-24-04458-f001" class="html-fig">Figure 1</a>c. (<b>c</b>) Raw measurement data of induced magnetic field <b>b</b> for a total cycle length of 1 s for the same sensor. Insets show initial current source oscillations, red lines mark the area of data extraction in the second half of each plateau.</p>
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<p>Induced magnetic fields for the sensor marked in red in <a href="#sensors-24-04458-f001" class="html-fig">Figure 1</a>c, for (<b>a</b>) horizontally applied magnetic field from single steady (red) and consecutive two-field (black) excitation scheme, and for (<b>b</b>) vertically applied magnetic field from single steady (purple) and consecutive two-field (grey) excitation scheme. The demodulated values of the two-field excitation refer to the experiment with the lowest possible cycle time of 3 s.</p>
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<p>Reconstructed time-averaged velocity field of the consecutive excitation approach with a total cycle length of 3 s in a blended vector and streamline visualization: (<b>a</b>) side-view and (<b>b</b>) top-view.</p>
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<p>Induced magnetic field for the direct induction coil marked in red in <a href="#sensors-24-04458-f001" class="html-fig">Figure 1</a>c, for a concurrent excitation with sinusoidal schemes with (<b>a</b>) <span class="html-italic">f</span><sub>horizontal</sub> = 1 Hz and (<b>b</b>) <span class="html-italic">f</span><sub>vertical</sub> = 2 Hz in comparison with the respective single-field excitation (AC) and in relation to the steady (DC) excitation measured with fluxgate probes (cf. <a href="#sensors-24-04458-f004" class="html-fig">Figure 4</a>).</p>
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16 pages, 4658 KiB  
Article
Assessing the Impact of Brackish Water on Soil Salinization with Time-Lapse Inversion of Electromagnetic Induction Data
by Lorenzo De Carlo and Mohammad Farzamian
Land 2024, 13(7), 961; https://doi.org/10.3390/land13070961 - 30 Jun 2024
Viewed by 1127
Abstract
Over the last decade, electromagnetic induction (EMI) measurements have been increasingly used for investigating soil salinization caused by the use of brackish or saline water as an irrigation source. EMI measurements proved to be a powerful tool for providing spatial information on the [...] Read more.
Over the last decade, electromagnetic induction (EMI) measurements have been increasingly used for investigating soil salinization caused by the use of brackish or saline water as an irrigation source. EMI measurements proved to be a powerful tool for providing spatial information on the investigated soil because of the correlation between the output geophysical parameter, i.e., the electrical conductivity, to soil moisture and salinity. In addition, their non-invasive nature and their capability to collect a high amount of data over broad areas and in a relatively short time makes these measurements attractive for monitoring flow and transport dynamics, which are otherwise undetectable with conventional measurements. In an experimental field, EMI measurements were collected during the growth season of tomatoes and irrigated with three different irrigation strategies. Time-lapse data were collected over three months in order to visualize changes in electrical conductivity associated with soil salinity. A rigorous time-lapse inversion procedure was set for modeling the soil salinization induced by brackish irrigation water. A clear soil response in terms of an increase in electrical conductivity (EC) in the upper soil layer confirmed the reliability of the geophysical tool to predict soil salinization trends. Full article
(This article belongs to the Special Issue Salinity Monitoring and Modelling at Different Scales)
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<p>Basics of ECa measurements.</p>
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<p>Normalized cumulative sensitivity (CS) for the three Mini-Explorer sensors S1, S2, and S3: (<b>a</b>) VCP configuration and (<b>b</b>) HCP coil configuration.</p>
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<p>Distribution of ECa data collected in the experimental field. The soil sampling was carried out on 31st August during the last EMI campaign.</p>
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<p>Inverted EC for the transect corresponding to plot A at five different time points: (<b>a</b>) 26th June; (<b>b</b>) 10th July; (<b>c</b>) 24th July; (<b>d</b>) 6th August; and (<b>e</b>) 31st August.</p>
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<p>Inverted EC differences over time for plot A after (<b>a</b>) 14 days; (<b>b</b>) 28 days; (<b>c</b>) 41 days; and (<b>d</b>) 66 days.</p>
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<p>Observed vs. calculated data for each time point observation for plot A: (<b>a</b>) 26th June; (<b>b</b>) 10th July; (<b>c</b>) 24th July; (<b>d</b>) 6th August; and (<b>e</b>) 31st August.</p>
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<p>Inverted EC for the transect corresponding to plot B at five different time points: (<b>a</b>) 26th June; (<b>b</b>) 10th July; (<b>c</b>) 24th July; (<b>d</b>) 6th August; and (<b>e</b>) 31st August.</p>
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<p>Inverted EC differences over time for plot B after (<b>a</b>) 14 days; (<b>b</b>) 28 days; (<b>c</b>) 41 days; and (<b>d</b>) 66 days.</p>
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<p>Inverted EC for transect belonging to plot C at five different time points: (<b>a</b>) 26th June; (<b>b</b>) 10th July; (<b>c</b>) 24th July; (<b>d</b>) 6th August; and (<b>e</b>) 31st August.</p>
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<p>Inverted EC differences over time for plot C after (<b>a</b>) 14 days; (<b>b</b>) 28 days; (<b>c</b>) 41 days; and (<b>d</b>) 66 days.</p>
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<p>Inverted EC vs. ECe calibration function. Statistically significant at <span class="html-italic">p</span>-value significance level: *** 0.001 levels of significance.</p>
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<p>Changes in EC at the end of the irrigation season for (<b>a</b>) plot A; (<b>b</b>) plot B; and (<b>c</b>) plot C.</p>
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26 pages, 10517 KiB  
Article
Estimation of Vehicle Traffic Parameters Using an Optical Distance Sensor for Use in Smart City Road Infrastructure
by Rafał Burdzik, Ireneusz Celiński, Minvydas Ragulskis, Vinayak Ranjan and Jonas Matijošius
J. Sens. Actuator Netw. 2024, 13(4), 35; https://doi.org/10.3390/jsan13040035 - 21 Jun 2024
Viewed by 981
Abstract
In recent decades, the dynamics of road vehicle traffic have significantly evolved, compelling traffic engineers to develop innovative traffic monitoring solutions, especially for dense road networks. Traditional methods for measuring traffic volume along road sections may no longer suffice for modern traffic control [...] Read more.
In recent decades, the dynamics of road vehicle traffic have significantly evolved, compelling traffic engineers to develop innovative traffic monitoring solutions, especially for dense road networks. Traditional methods for measuring traffic volume along road sections may no longer suffice for modern traffic control systems. This is particularly true for induction loops, a widely used method since the last century. In contrast, measuring techniques using microwaves or visible light offer better accuracy but are often hindered by the high cost of sensors. This paper presents new techniques for measuring traffic flow and other parameters that adapt to changing traffic dynamics using low-cost optical distance sensors. Our study demonstrates that the integration of multiple monitoring approaches enhances measurement accuracy, contingent on the dynamics and specific characteristics of the traffic. The results indicate that cheap optical distance sensors are particularly well suited for use in smart city road networks. Full article
(This article belongs to the Section Network Services and Applications)
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<p>Changes in the dynamics and spatial distribution of traffic within road networks.</p>
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<p>The vehicle motion measurement systems, showing (<b>a</b>) the system and a laptop computer, (<b>b</b>) the system alone, (<b>c</b>) the user interface that allows the manual recording of traffic intensity on a tablet computer, and (<b>d</b>) the fully autonomous version two of the measurement system.</p>
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<p>Overview of the measurement system.</p>
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<p>Characteristics of the Sharp GP2Y0A710K0F optical distance sensor, showing (<b>a</b>) the voltage response and (<b>b</b>) a comparison of the sensor price versus the price of a road bollard. Source: [<a href="#B22-jsan-13-00035" class="html-bibr">22</a>].</p>
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<p>An excerpt of the recorded vehicle detections for traffic moving to the right.</p>
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<p>An excerpt of the recorded vehicle detections for traffic moving to the left.</p>
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<p>An excerpt of the recorded vehicle detections, showing both traffic moving to the left (blue) and traffic moving to the right (orange).</p>
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<p>Dynamics versus homogeneity of the recorded vehicle detections.</p>
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<p>The distance measurement results (more than 45,000 samples).</p>
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<p>Analysis of the spatial relationships in the distance measurement data.</p>
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<p>The distance measurement results filtered to show measurements below 6.5 m.</p>
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<p>The factors that affect distance measured by the distance sensor.</p>
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<p>Results from the first 7 min of distance measurements for the vehicles moving to the right, with results filtered between 0.9 and 3 m.</p>
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<p>Dynamics analysis of selected distance measurements, with key elements highlighted.</p>
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<p>Analysis of traffic based on gap and headway between vehicles, (<b>a</b>) LISA procedure and (<b>b</b>) vehicle interaction in spatial regimes [<a href="#B36-jsan-13-00035" class="html-bibr">36</a>].</p>
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<p>Anomalous data obtained during the experimentation. The regions of interest are indicated by red outlines (<b>a</b>) measurements beyond the distance declared by the manufacturer, (<b>b</b>) dead zone, (<b>c</b>) measurement at section of the near side lane (<b>d</b>) measurement at section of the far side lane.</p>
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<p>Superimposition of the manual measurements with the distance sensor measurements. The blue lines indicate the vehicles moving to the left, and the orange lines indicate the vehicles moving to the right.</p>
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<p>Illustration of several different height zones at which the distance sensor could be located, and the problems that each may entail with regard to vehicle detection.</p>
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<p>Version two of the measurement system, showing (<b>a</b>) a network of three connected sensors, (<b>b</b>) example data, (<b>c</b>) the new sensor unit with infrared calibration subsystem, and (<b>d</b>) an elevated sensor to account for low field compensation.</p>
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<p>Selected results of an extended study of the Katowice street network, (<b>a</b>) main roads, and (<b>b</b>) local streets.</p>
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