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2.
Front Public Health ; 12: 1411489, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939567

RESUMO

Introduction: Human prion disease (PrD), a group of fatal and transmissible neurodegenerative diseases, consists of Creutzfeldt-Jakob disease (CJD), kuru, fatal familial insomnia (FFI), Gerstmann-Sträussler-Scheinker disease (GSS), and variably protease-sensitive prionopathy (VPSPr). The emergence of bovine spongiform encephalopathy (BSE) in cattle and variant CJD (vCJD) has greatly threatened public health, both in humans and animals. Since the 1990's, dozens of countries and territories have conducted PrD surveillance programs. Methods: In this study, the case numbers and alternative trends of different types of PrD globally and in various countries or territories from 1993 to 2020 were collected and analyzed based on the data from the websites of the international and national PrD surveillance programs, as well as from relevant publications. Results: The total numbers of the reported PrD and sporadic CJD (sCJD) cases in 34 countries with accessible annual case numbers were 27,872 and 24,623, respectively. The top seven countries in PrD cases were the USA (n = 5,156), France (n = 3,276), Germany (n = 3,212), Italy (n = 2,995), China (n = 2,662), the UK (n = 2,521), Spain (n = 1,657), and Canada (n = 1,311). The annual PrD case numbers and mortalities, either globally or in the countries, showed an increased trend in the past 27 years. Genetic PrD cases accounted for 10.83% of all reported PrD cases; however, the trend varied largely among the different countries and territories. There have been 485 iatrogenic CJD (iCJD) cases and 232 vCJD cases reported worldwide. Discussion: The majority of the countries with PrD surveillance programs were high- and upper-middle-income countries. However, most low- and lower-middle-income countries in the world did not conduct PrD surveillance or even report PrD cases, indicating that the number of human PrD cases worldwide is markedly undervalued. Active international PrD surveillance for both humans and animals is still vital to eliminate the threat of prion disease from a public health perspective.


Assuntos
Saúde Global , Doenças Priônicas , Humanos , Doenças Priônicas/epidemiologia , Saúde Global/estatística & dados numéricos , Síndrome de Creutzfeldt-Jakob/epidemiologia , Animais , Bovinos
3.
Sci Data ; 11(1): 694, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926452

RESUMO

Functional traits reveal the adaptive strategies of species to their environment, and are relevant to the formation of communities, the function of ecosystems, and the mechanisms underlying biodiversity. However, trait databases have not been established for most biological taxa, especially for insects, which encompass a vast number of species. This study measured the morphological traits of 307 species of Heteroptera insects collected in 2019 from the "Xishuangbanna Priority Conservation Area" in Southwest China using sweep netting and light trapping methods. This study provides a dataset for 307 Heteroptera species, comprising 34 morphometric measurements and 17 morphological traits. The dataset contains information on species sex, abundance, and the average, maximum, and minimum values of traits. This dataset facilitates an enhanced understanding of the functional traits and ecological associations of Heteroptera insects and offers opportunities for exploring a more diverse range of research topics.


Assuntos
Biodiversidade , Heterópteros , Animais , China , Heterópteros/anatomia & histologia , Heterópteros/classificação , Feminino , Masculino , Ecossistema
4.
PLoS One ; 19(5): e0302360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38768155

RESUMO

Attendance absences have a substantial impact on student's future physical and mental health as well as academic progress. Numerous personal, familial, and social issues are among the causes of student absences. Any kind of absence from school should be minimized. Extremely high rates of student absences may indicate the abrupt commencement of a serious school health crisis or public health crisis, such as the spread of tuberculosis or COVID-19, which provides school health professionals with an early warning. We take the extreme values in absence data as the object and attempt to apply the extreme value theory (EVT) to describe the distribution of extreme values. This study aims to predict extreme instances of student absences. School health professionals can take preventative measures to reduce future excessive absences, according to the predicted results. Five statistical distributions were applied to individually characterize the extreme values. Our findings suggest that EVT is a useful tool for predicting extreme student absences, thereby aiding preventative measures in public health.


Assuntos
Absenteísmo , COVID-19 , Estudantes , Humanos , China/epidemiologia , Estudantes/estatística & dados numéricos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Instituições Acadêmicas , Masculino , Feminino , Criança , Adolescente
5.
Org Lett ; 26(15): 3195-3201, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38563798

RESUMO

A facile photocatalytic radical [4+2] cyclization of N-aryl-α-amino acids with various alkenes to access structurally polysubstituted tetrahydroquinolines has been developed. Using a simple bipyridine as a catalyst, different N-aryl-α-amino acids could be utilized as the radical precursors to react with diverse electrophilic alkenes, including exocyclic terminal alkenes, acyclic terminal alkenes, and cycloalkenes, producing 10 types of nitrogen-containing heterocyclic compounds fused in multiple frameworks in generally moderate yields with good diastereoselectivities. Scale-up synthesis and transformations of the products further demonstrated the synthetic application of this protocol. Moreover, a decarboxylative radial pathway via a proton-coupled electron transfer process for illustration of this [4+2] cyclization was proposed on the basis of the control experiments. This process is highlighted by a simple bipyridine photocatalysis, mild reaction conditions, various N-aryl-α-amino acids and alkene materials, and application for the modification of natural products.

6.
Eur J Med Chem ; 270: 116376, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38569433

RESUMO

A variety of novel indole-derived γ-hydroxy propiolate esters were designed, synthesized, and evaluated for their anti-inflammatory activity in-vitro and in-vivo. According to the nitric oxide (NO) inhibitory analysis, all compounds showed potent NO inhibitory ability in a dose-dependent manner, with no apparent cytotoxicity. The model compound, L-37, also exhibited significant potency in PGE2 inhibition. In addition, compounds L-37 and L-39 can downregulate the expression of COX-2 enzyme at 5 µM via ELISA experiment. Compound L-37 (1 µM) also inhibited the PGF1 production as well as the expression of COX-1, but displayed weak inhibition activity towards the Leukotrienes (LT) and Thromboxane-B2 (TXB-2) production. However, the expression of 5-LOX was significantly inhibited by compound L-39 at 5 µM. Xylene-induced ear edema model was explored for in-vivo anti-inflammatory evaluation, compound L-37 showed similar inhibitory activity compared with celecoxib, approximately 80% at 50 mg/kg dosage. Every outcome showed that the newly synthesized compounds can effectively inhibit inflammation.


Assuntos
Anti-Inflamatórios não Esteroides , Anti-Inflamatórios , Humanos , Anti-Inflamatórios/efeitos adversos , Celecoxib , Ciclo-Oxigenase 2/metabolismo , Indóis , Edema/induzido quimicamente , Edema/tratamento farmacológico , Simulação de Acoplamento Molecular , Inibidores de Ciclo-Oxigenase 2/farmacologia , Relação Estrutura-Atividade
7.
BMC Public Health ; 24(1): 1134, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654317

RESUMO

BACKGROUND: Hypertension is one of the major public health problems in China. Limited evidence exists regarding sex differences in the association between hypertension and air pollutants, as well as the impact of dietary factors on the relationship between air pollutants and hypertension. The aim of this study was to investigate the sex-specific effects of dietary patterns on the association between fine particulate matter (PM2.5), ozone(O3) and hypertension in adults residing in Jiangsu Province of China. METHODS: A total of 3189 adults from the 2015 China Adult Chronic Disease and Nutrition Surveillance in Jiangsu Province were included in this study. PM2.5 and O3 concentrations were estimated using satellite space-time models and assigned to each participant. Dietary patterns were determined by reduced rank regression (RRR), and multivariate logistic regression was used to assess the associations of the obtained dietary patterns with air pollutants and hypertension risk. RESULTS: After adjusting for confounding variables, we found that males were more sensitive to long-term exposure to PM2.5 (Odds ratio (OR) = 1.42 95%CI:1.08,1.87), and females were more sensitive to long-term exposure to O3 (OR = 1.61 95%CI:1.15,2.23). Traditional southern pattern identified through RRR exhibited a protective effect against hypertension in males (OR = 0.73 95%CI: 0.56,1.00). The results of the interaction between dietary pattern score and PM2.5 revealed that adherence to traditional southern pattern was significantly associated with a decreased risk of hypertension in males (P < 0.05), while no significant association was observed among females. CONCLUSIONS: Our findings suggested that sex differences existed in the association between dietary patterns, air pollutants and hypertension. Furthermore, we found that adherence to traditional southern pattern may mitigate the risk of long-term PM2.5 exposure-induced hypertension in males.


Assuntos
Poluentes Atmosféricos , Hipertensão , Ozônio , Material Particulado , Humanos , Masculino , Feminino , Hipertensão/epidemiologia , China/epidemiologia , Pessoa de Meia-Idade , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Material Particulado/análise , Material Particulado/efeitos adversos , Adulto , Ozônio/análise , Ozônio/efeitos adversos , Fatores Sexuais , Dieta/estatística & dados numéricos , Idoso , Exposição Ambiental/efeitos adversos , Padrões Dietéticos
8.
Transl Vis Sci Technol ; 13(4): 8, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38568606

RESUMO

Purpose: The assessment of retinal image (RI) quality holds significant importance in both clinical trials and large datasets, because suboptimal images can potentially conceal early signs of diseases, thereby resulting in inaccurate medical diagnoses. This study aims to develop an automatic method for Retinal Image Quality Assessment (RIQA) that incorporates visual explanations, aiming to comprehensively evaluate the quality of retinal fundus images (RIs). Methods: We developed an automatic RIQA system, named Swin-MCSFNet, utilizing 28,792 RIs from the EyeQ dataset, as well as 2000 images from the EyePACS dataset and an additional 1,000 images from the OIA-ODIR dataset. After preprocessing, including cropping black regions, data augmentation, and normalization, a Swin-MCSFNet classifier based on the Swin-Transformer for multiple color-space fusion was proposed to grade the quality of RIs. The generalizability of Swin-MCSFNet was validated across multiple data centers. Additionally, for enhanced interpretability, a Score-CAM-generated heatmap was applied to provide visual explanations. Results: Experimental results reveal that the proposed Swin-MCSFNet achieves promising performance, yielding a micro-receiver operating characteristic (ROC) of 0.93 and ROC scores of 0.96, 0.81, and 0.96 for the "Good," "Usable," and "Reject" categories, respectively. These scores underscore the accuracy of RIQA based on Swin-MCSF in distinguishing among the three categories. Furthermore, heatmaps generated across different RIQA classification scores and various color spaces suggest that regions in the retinal images from multiple color spaces contribute significantly to the decision-making process of the Swin-MCSFNet classifier. Conclusions: Our study demonstrates that the proposed Swin-MCSFNet outperforms other methods in experiments conducted on multiple datasets, as evidenced by the superior performance metrics and insightful Score-CAM heatmaps. Translational Relevance: This study constructs a new retinal image quality evaluation system, which will contribute to the subsequent research of retinal images.


Assuntos
Retina , Fundo de Olho , Retina/diagnóstico por imagem
9.
Front Endocrinol (Lausanne) ; 15: 1374689, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532899

RESUMO

Diabetic neuropathy is the most common complication of diabetes and lacks effective treatments. Although sensory dysfunction during the early stages of diabetes has been extensively studied in various animal models, the functional and morphological alterations in sensory and motor systems during late stages of diabetes remain largely unexplored. In the current work, we examined the influence of diabetes on sensory and motor function as well as morphological changes in late stages of diabetes. The obese diabetic Leprdb/db mice (db/db) were used for behavioral assessments and subsequent morphological examinations. The db/db mice exhibited severe sensory and motor behavioral defects at the age of 32 weeks, including significantly higher mechanical withdrawal threshold and thermal latency of hindpaws compared with age-matched nondiabetic control animals. The impaired response to noxious stimuli was mainly associated with the remarkable loss of epidermal sensory fibers, particularly CGRP-positive nociceptive fibers. Unexpectedly, the area of CGRP-positive terminals in the spinal dorsal horn was dramatically increased in diabetic mice, which was presumably associated with microglial activation. In addition, the db/db mice showed significantly more foot slips and took longer time during the beam-walking examination compared with controls. Meanwhile, the running duration in the rotarod test was markedly reduced in db/db mice. The observed sensorimotor deficits and motor dysfunction were largely attributed to abnormal sensory feedback and muscle atrophy as well as attenuated neuromuscular transmission in aged diabetic mice. Morphological analysis of neuromuscular junctions (NMJs) demonstrated partial denervation of NMJs and obvious fragmentation of acetylcholine receptors (AChRs). Intrafusal muscle atrophy and abnormal muscle spindle innervation were also detected in db/db mice. Additionally, the number of VGLUT1-positive excitatory boutons on motor neurons was profoundly increased in aged diabetic mice as compared to controls. Nevertheless, inhibitory synaptic inputs onto motor neurons were similar between the two groups. This excitation-inhibition imbalance in synaptic transmission might be implicated in the disturbed locomotion. Collectively, these results suggest that severe sensory and motor deficits are present in late stages of diabetes. This study contributes to our understanding of mechanisms underlying neurological dysfunction during diabetes progression and helps to identify novel therapeutic interventions for patients with diabetic neuropathy.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Neuropatias Diabéticas , Camundongos , Humanos , Animais , Idoso , Lactente , Peptídeo Relacionado com Gene de Calcitonina , Atrofia Muscular
10.
BMC Public Health ; 24(1): 671, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431552

RESUMO

BACKGROUND: Metabolic syndrome (MetS) is a health issue consisting of multiple metabolic abnormalities. The impact of exposure to volatile organic compounds (VOCs) on MetS and its components remains uncertain. This study aimed to assess the associations of individual urinary metabolites of VOC (mVOCs) and mVOC mixtures with MetS and its components among the general adult population in the United States. METHODS: A total of 5345 participants with eligible data were filtered from the 2011-2020 cycles of the National Health and Nutrition Examination Survey. Multivariate logistic regression models were applied to assess the associations of individual mVOCs with MetS and its components. The least absolute shrinkage and selection operator (LASSO) regression models were constructed to identify more relevant mVOCs. The weight quantile sum regression model was applied to further explore the links between mVOC co-exposure and MetS and its components. RESULTS: The results indicated positive associations between multiple mVOCs and MetS, including CEMA, DHBMA, and HMPMA. CEMA was found to be positively correlated with all components of MetS. HMPMA was associated with elevated triglyceride (TG), reduced high-density lipoprotein, and fasting blood glucose (FBG) impairment; 3HPMA was associated with an elevated risk of high TG and FBG impairment; and DHBMA had positive associations with elevated TG and high blood pressure. The co-exposure of LASSO-selected mVOCs was associated with an increased risk of elevated TG, high blood pressure, and FBG impairment. CONCLUSION: Positive associations of certain individual urinary mVOCs and mVOC mixtures with MetS and its components were observed by utilizing multiple statistical models and large-scale national data. These findings may serve as the theoretical basis for future experimental and mechanistic studies and have important implications for public health.


Assuntos
Hipertensão , Síndrome Metabólica , Compostos Orgânicos Voláteis , Adulto , Humanos , Síndrome Metabólica/diagnóstico , Fatores de Risco , Estudos Transversais , Inquéritos Nutricionais
11.
World J Diabetes ; 15(1): 105-125, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38313853

RESUMO

BACKGROUND: Development of end-stage renal disease is predominantly attributed to diabetic nephropathy (DN). Previous studies have indicated that myricetin possesses the potential to mitigate the pathological alterations observed in renal tissue. Nevertheless, the precise molecular mechanism through which myricetin influences the progression of DN remains uncertain. AIM: To investigate the effects of myricetin on DN and explore its potential therapeutic mechanism. METHODS: Db/db mice were administered myricetin intragastrically on a daily basis at doses of 50 mg/kg or 100 mg/kg for a duration of 12 wk. Subsequently, blood and urine indexes were assessed, along with examination of renal tissue pathology. Kidney morphology and fibrosis were evaluated using various staining techniques including hematoxylin and eosin, periodic acid-Schiff, Masson's trichrome, and Sirius-red. Additionally, high-glucose culturing was conducted on the RAW 264.7 cell line, treated with 25 mM myricetin or co-administered with the PI3K/Akt inhibitor LY294002 for a period of 24 h. In both in vivo and in vitro settings, quantification of inflammation factor levels was conducted using western blotting, real-time qPCR and ELISA. RESULTS: In db/db mice, administration of myricetin led to a mitigating effect on DN-induced renal dysfunction and fibrosis. Notably, we observed a significant reduction in expressions of the kidney injury markers kidney injury molecule-1 and neutrophil gelatinase associated lipocalin, along with a decrease in expressions of inflammatory cytokine-related factors. Furthermore, myricetin treatment effectively inhibited the up-regulation of tumor necrosis factor-alpha, interleukin-6, and interluekin-1ß induced by high glucose in RAW 264.7 cells. Additionally, myricetin modulated the M1-type polarization of the RAW 264.7 cells. Molecular docking and bioinformatic analyses revealed Akt as the target of myricetin. The protective effect of myricetin was nullified upon blocking the polarization of RAW 264.7 via inhibition of PI3K/Akt activation using LY294002. CONCLUSION: This study demonstrated that myricetin effectively mitigates kidney injury in DN mice through the regulation of macrophage polarization via the PI3K/Akt signaling pathway.

12.
Sensors (Basel) ; 24(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339726

RESUMO

The precise building extraction from high-resolution remote sensing images holds significant application for urban planning, resource management, and environmental conservation. In recent years, deep neural networks (DNNs) have garnered substantial attention for their adeptness in learning and extracting features, becoming integral to building extraction methodologies and yielding noteworthy performance outcomes. Nonetheless, prevailing DNN-based models for building extraction often overlook spatial information during the feature extraction phase. Additionally, many existing models employ a simplistic and direct approach in the feature fusion stage, potentially leading to spurious target detection and the amplification of internal noise. To address these concerns, we present a multi-scale attention network (MSANet) tailored for building extraction from high-resolution remote sensing images. In our approach, we initially extracted multi-scale building feature information, leveraging the multi-scale channel attention mechanism and multi-scale spatial attention mechanism. Subsequently, we employed adaptive hierarchical weighting processes on the extracted building features. Concurrently, we introduced a gating mechanism to facilitate the effective fusion of multi-scale features. The efficacy of the proposed MSANet was evaluated using the WHU aerial image dataset and the WHU satellite image dataset. The experimental results demonstrate compelling performance metrics, with the F1 scores registering at 93.76% and 77.64% on the WHU aerial imagery dataset and WHU satellite dataset II, respectively. Furthermore, the intersection over union (IoU) values stood at 88.25% and 63.46%, surpassing benchmarks set by DeepLabV3 and GSMC.

13.
Dev Cogn Neurosci ; 66: 101346, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38290421

RESUMO

Risk-taking often occurs in childhood as a compex outcome influenced by individual, family, and social factors. The ability to govern risky decision-making in a balanced manner is a hallmark of the integrity of cognitive and affective development from childhood to adulthood. The Triadic Neural Systems Model posits that the nuanced coordination of motivational approach, avoidance and prefrontal control systems is crucial to regulate adaptive risk-taking and related behaviors. Although widely studied in adolescence and adulthood, how these systems develop in childhood remains elusive. Here, we show heterogenous age-related differences in the triadic neural systems involved in risky decision-making in 218 school-age children relative to 80 young adults. Children were generally less reward-seeking and less risk-taking than adults, and exhibited gradual increases in risk-taking behaviors from 6 to 12 years-old, which are associated with age-related differences in brain activation patterns underlying reward and risk processing. In comparison to adults, children exhibited weaker activation in control-related prefrontal systems, but stronger activation in reward-related striatal systems. Network analyses revealed that children showed greater reward-related functional connectivity within and between the triadic systems. Our findings support an immature and unbalanced developmental view of the core neurocognitive systems involved in risky decision-making and related behaviors in middle to late childhood.

17.
Food Funct ; 15(4): 2064-2077, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38295369

RESUMO

Aim: This study used urinary caffeine and its metabolites to evaluate their relationships with liver steatosis and advanced liver fibrosis. Methods: A total of 2068 adult participants with required data were filtered from the 2009-2014 National Health and Nutrition Examination Survey (NHANES) cycles. Non-invasive scores were applied to define liver steatosis and advanced liver fibrosis. Logistic regression models, weighted quantile sum (WQS) regression models, quantile-based g-computation (QG-Comp) models, and restricted cubic spline (RCS) regression models were used to assess the associations of urinary caffeine and its metabolites with liver steatosis and advanced liver fibrosis. A series of additional analyses were conducted to examine the subgroup-specific differences and test the robustness of the observed results. Results: The major caffeine metabolite mixture and most individual caffeine metabolites were found to be negatively associated with the risk of advanced liver fibrosis with subgroup-specific variations. Only 7-MX consistently showed a negative association with liver steatosis in all analyses, while no association was observed between the major caffeine metabolite mixture and liver steatosis. Conclusion: The major caffeine metabolite mixture and most individual urinary caffeine metabolites exhibited inverse associations with advanced liver fibrosis with subgroup differences. Further prospective and experimental studies are urgently needed to verify our results and further identify the possible mechanisms.


Assuntos
Cafeína , Fígado Gorduroso , Adulto , Humanos , Estudos Transversais , Inquéritos Nutricionais , Cirrose Hepática
18.
Environ Toxicol ; 39(3): 1107-1118, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37823609

RESUMO

The Chinese medicine formula Chanling Gao (CLG) exhibits significant tumor inhibitory effects in colorectal cancer (CRC) nude mice. However, the detailed mechanisms remain elusive. CRC in situ nude mouse models were treated with CLG. Small animal magnetic resonance imaging (MRI) tracked tumor progression, and overall health metrics such as food and water intake, body weight, and survival were monitored. Posttreatment, tissues and blood were analyzed for indicators of tumor inhibition and systemic effects. Changes in vital organs were observed via stereoscope and hematoxylin-eosin staining. Immunohistochemistry quantified HIF-1α and P70S6K1 protein expression in xenografts. Double labeling was used to statistically analyze vascular endothelial growth factor (VEGF) and CD31 neovascularization. Enzyme-linked immunosorbent assay was used to determine the levels of VEGF, MMP-2, MMP-9, IL-6, and IL-10 in serum, tumors, and liver. Western blotting was used to assess the expression of the PI3K/Akt/mTOR signaling pathway-related factors TGF-ß1 and smad4 in liver tissues. CLG inhibited tumor growth, improved overall health metrics, and ameliorated abnormal blood cell counts in CRC nude mice. CLG significantly reduced tumor neovascularization and VEGF expression in tumors and blood. It also suppressed HIF-1α, EGFR, p-PI3K, Akt, p-Akt, and p-mTOR expression in tumors while enhancing PTEN oncogene expression. Systemic improvements were noted, with CLG limiting liver metastasis, reducing pro-inflammatory cytokines IL-6 and IL-10 in liver tissues, decreasing MMP-2 in blood and MMP-2 and MMP-9 in tumors, and inhibiting TGF-ß1 expression in liver tissues. CLG can enhance survival quality and inhibit tumor growth in CRC nude mice, likely through the regulation of the PI3K/Akt/mTOR signaling pathway.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Camundongos , Animais , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator de Crescimento Transformador beta1 , Fator A de Crescimento do Endotélio Vascular/metabolismo , Camundongos Nus , Interleucina-10 , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Interleucina-6 , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral
19.
Micromachines (Basel) ; 14(12)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38138405

RESUMO

Taking into consideration the inaccurate temperature predictions in traditional thermal models of power devices, we undertook a study on the temperature rise characteristics of heterojunction bipolar transistors (HBTs) with a two-dimensional cross-sectional structure including a sub-collector region. We developed a current-adjusted polynomial electro-thermal coupling model based on investigating floating heat sources. This model was developed using precise simulation data acquired from SILVACO (Santa Clara, CA, USA). Additionally, we utilized COMSOL software (version 5.6) to simulate the temperature distribution within parallel power cells, examining further impacts resulting from thermal coupling. The research findings indicate that the rise in current induces modifications in the local carrier concentration, thereby prompting variations in the local electric field, including changes in the heat source's peak location and intensity. The device's peak temperature exhibits a non-linear trend regulated by the current, revealing an error margin of less than 1.5% in the proposed current-corrected model. At higher current levels, the drift of the heat source leads to an increase in the heat dissipation path and reduces the coupling strength between parallel devices. Experiments were performed on 64 GaAs (gallium arsenide) HBT-based power cells using a QFI infrared imaging system. Compared to the traditional temperature calculation model, the proposed model increased the accuracy by 6.84%, allowing for more precise predictions of transistor peak temperatures in high-power applications.

20.
Wei Sheng Yan Jiu ; 52(6): 930-935, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38115657

RESUMO

OBJECTIVE: This study aimed to investigate vitamin A and vitamin D conditions and related factors among children and adolescents aged 6-17 years in Jiangsu Province of China. METHODS: All the data were derived from China Nutrition and Health Surveillance of Children and Lactating Mothers in 2016-2017. By applying multiple stage stratified cluster random sampling method, 3244 children aged 6-17 years were selected from 12 survey sites in Jiangsu Province. Face to face interview, physical measurements and 6 mL blood sample were used to collect the general information, anthropometric information and blood nutritional indexes of the participants. Multivariate Logistic analysis was used for vitamin A and vitamin D conditions to test related factors. RESULTS: The prevalence of vitamin A deficiency and marginal deficiency was 0.8% and 15.8%, respectively.23.2% of the participants had vitamin D deficiency, 54.2% had vitamin D insufficiency and 4.8% had vitamin A insufficiency combined with vitamin D deficiency. Age group, weight levels, screen time and mother's education levels are the relevant factors of vitamin A insufficiency in children and adolescents. The related factors of vitamin D deficiency among children and adolescents are gender, age group, residence, physical activity level, screen time and mother's education levels. Gender, residence, weight levels, screen time and mother's education levels are the related factors of vitamin A insufficiency combined with vitamin D deficiency. CONCLUSION: Vitamin A insufficiency and vitamin D deficiency are at high epidemic levels among children and adolescents in Jiangsu Province in 2016-2017.


Assuntos
Deficiência de Vitamina D , Vitamina D , Criança , Feminino , Humanos , Adolescente , Vitamina A , Estado Nutricional , Lactação , Vitaminas , Deficiência de Vitamina D/epidemiologia , Prevalência
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