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1.
Ecotoxicol Environ Saf ; 262: 115200, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37392662

RESUMEN

Fine particulate matter (PM2.5) and high-fat diet (HFD) are known to contribute to blood glucose metabolic disorders. However, limited research has investigated the combined impact of PM2.5 and HFD on blood glucose metabolism. This study aimed to explore the joint effects of PM2.5 and HFD on blood glucose metabolism in rats using serum metabolomics and to identify involved metabolites and metabolic pathways. The 32 male Wistar rats were exposed to filtered air (FA) or PM2.5 (real-world inhaled, concentrated PM2.5, 8 times the ambient level, ranging from 131.42 to 773.44 µg/m3) and fed normal diet (ND) or HFD for 8 weeks. The rats were divided into four groups (n = 8/group): ND-FA, ND-PM2.5, HFD-FA and HFD-PM2.5 groups. Blood samples were collected to determine fasting glucose (FBG), plasma insulin and glucose tolerance test and HOMA Insulin Resistance (HOMA-IR) index was calculated. Finally, the serum metabolism of rats was analyzed by ultra-high performance liquid chromatography/mass spectrometry (UHPLC-MS). Then we constructed the partial least squares discriminant analysis (PLS-DA) model to screen the differential metabolites, and performed pathway analysis to screen the main metabolic pathways. Results showed that combined effect of PM2.5 and HFD caused changes in glucose tolerance, increased FBG levels and HOMA-IR in rats and there were interactions between PM2.5 and HFD in FBG and insulin. By metabonomic analysis, the serum differential metabolites pregnenolone and progesterone, which involved in steroid hormone biosynthesis, were two different metabolites in the ND groups. In the HFD groups, the serum differential metabolites were L-tyrosine and phosphorylcholine, which involved in glycerophospholipid metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis. When PM2.5 and HFD coexist, they may lead to more severe and complex effects on glucose metabolism by affecting lipid metabolism and amino acid metabolism. Therefore, reducing PM2.5 exposure and controlling dietary structure are important measures for preventing and reducing glucose metabolism disorders.

2.
Cogn Process ; 24(2): 173-186, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36708402

RESUMEN

To investigate the mechanism of episodic foresight of different valences on intertemporal decision-making, this study examined the mediating role of future self-continuity in the influence of episodic foresight on intertemporal decision-making and the moderating role of perceived control in two experiments. The results found that (1) future self-continuity mediated the effect of episodic foresight on individuals' intertemporal decision-making; and (2) perceived control moderated the indirect effect of episodic foresight on intertemporal decision-making through future self-continuity. Under low perceived control, individuals with positive episodic foresight had stronger future self-continuity and preferred future options, while individuals with negative episodic foresight had lower future self-continuity. In contrast, under high perceived control, individuals with different episodic foresight potencies did not show significant differences in their future self-continuity levels, but all showed higher levels and tended to choose the delayed option when faced with an intertemporal choice. From the perspective of the self-cognition, this study provided new insights into the relationship between episodic foresight and intertemporal decision-making and the psychological mechanisms of intertemporal decision-making.


Asunto(s)
Descuento por Demora , Humanos , Cognición , Imaginación
3.
J Occup Environ Hyg ; 20(3-4): 136-142, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36799881

RESUMEN

The goal of this study was to evaluate the relationship between ratings of perceived exertion (RPE) and relative strength with respect to baseline for a fatiguing free dynamic task targeting the upper extremity, namely simulated order picking, and determine whether the relationship remains the same for different conditions (i.e., pace and weight) and with fatigue. Fourteen participants (seven males, seven females) performed four sessions that included two 45-min work periods separated by 15 min of rest. The work periods involved picking weighted bottles from shoulder height and packaging them at waist height for four combinations of bottle mass and picking rate: 2.5 kg-15 bottles per minute (bpm), 2.5 kg-10 bpm, 2.5 kg-5 bpm, and 1.5 kg-15 bpm. Participants reported their RPEs every 5 min and performed a maximum isometric shoulder flexion exertion every 9 min. Pearson product-moment correlation was used to evaluate the linear relationship between RPE and relative strength for each subject and work period. Then, the effects of condition and work period on the average relationship were assessed using a repeated-measures analysis of variance (ANOVA). For the first 45-min period, there were no significantly different correlations between RPE and relative strength across conditions (average r = -0.62 (standard deviation = 0.38); p = 0.57). There was a significant decrease in average correlation for the second work period (r = -0.39 (0.53)). These results suggest that individual subjective responses consistently increase while relative strength declines when starting from a non-fatigued state. However, correlations are weaker when re-engaging in work following incomplete recovery. Thus, starting fatigue levels should be accounted for when considering the expected relationship between RPE and relative strength.


Asunto(s)
Esfuerzo Físico , Extremidad Superior , Masculino , Femenino , Humanos , Esfuerzo Físico/fisiología , Hombro , Descanso
4.
Pharmacol Res ; 184: 106422, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36058431

RESUMEN

Targeting cardiomyocyte plasticity has emerged as a new strategy for promoting heart repair after myocardial infarction. However, the precise mechanistic network underlying heart regeneration is not completely understood. As noncoding RNAs, circular RNAs (circRNAs) play essential roles in regulating cardiac physiology and pathology. The present study aimed to investigate the potential roles of circMdc1 in cardiac repair after injury and elucidate its underlying mechanisms. Here, we identified that circMdc1 levels were upregulated in postnatal mouse hearts but downregulated in the regenerative myocardium. The expression of circMdc1 in cardiomyocytes is sensitive to oxidative stress, which was attenuated by N-acetyl-cysteine. Enforced circMdc1 expression inhibited cardiomyocyte proliferation, while circMdc1 silencing led to cardiomyocyte cell cycle re-entry. In vivo, the cardiac-specific adeno-associated virus-mediated knockdown of circMdc1 promoted cardiac regeneration and heart repair accompanied by improved heart function. Conversely, circMdc1 overexpression blunted the regenerative capacity of neonatal hearts after apex resection. Moreover, circMdc1 was able to block the translation of its host gene Mdc1 specifically by binding to PABP, affecting DNA damage and the chromosome stability of cardiomyocytes. Furthermore, overexpression of Mdc1 caused damaged mouse hearts to regenerate and repair after myocardial infarction in vivo. Oxidative stress-sensitive circMdc1 plays an important role in cardiac regeneration and heart repair after injury by regulating DNA damage and chromosome stability in cardiomyocytes by blocking the translation of the host gene Mdc1.


Asunto(s)
Infarto del Miocardio , Miocitos Cardíacos , Animales , Animales Recién Nacidos , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proliferación Celular , Inestabilidad Cromosómica , Cisteína/metabolismo , Corazón/fisiología , Ratones , Infarto del Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Oxidantes/metabolismo , ARN Circular/genética , Regeneración/fisiología
5.
Risk Anal ; 42(8): 1852-1871, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33506515

RESUMEN

An incident in which a rail defect of size over a threshold value is noticed and the track is taken out of service is known as a service failure. This article aims at building accurate prediction models with binary outcome for risk of service failures on heavy haul rail segments. An analysis of the factors that influence the risk of a service failure is conducted and quantitative models are developed to predict locations where service failures are most likely to occur until the next inspection. To this end, data are collected from a Class I U.S. Railroads for six years from 2011 to 2016. Four prediction models (i.e., logistic regression, decision tree, multilayer perceptron, and gradient boosting classifier) are implemented and their results are compared. To account for the imbalanced classes between the normal operation and service failure, two treatments have been used including undersampling and oversampling. To improve the model performance, the parameters of each method are tuned using random search hyperparameter optimization. Later, bootstrap aggregation (or bagging) is incorporated into each method. The findings of the study show that the prediction performance is the highest when using bagging and oversampling as treatments with gradient boosting method. It was also identified that gross tonnage, presence of geometry defects, ambient temperature, segment length, and rail defect presence are the most important factors for predicting the risk of service failures. The results of this study are useful for railroads to develop effective strategies for rail inspections, preventive maintenance, and capital planning.

6.
Acta Pharmacol Sin ; 42(6): 921-931, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32839503

RESUMEN

The neonatal heart possesses the ability to proliferate and the capacity to regenerate after injury; however, the mechanisms underlying these processes are not fully understood. Melatonin has been shown to protect the heart against myocardial injury through mitigating oxidative stress, reducing apoptosis, inhibiting mitochondrial fission, etc. In this study, we investigated whether melatonin regulated cardiomyocyte proliferation and promoted cardiac repair in mice with myocardial infarction (MI), which was induced by ligation of the left anterior descending coronary artery. We showed that melatonin administration significantly improved the cardiac functions accompanied by markedly enhanced cardiomyocyte proliferation in MI mice. In neonatal mouse cardiomyocytes, treatment with melatonin (1 µM) greatly suppressed miR-143-3p levels. Silencing of miR-143-3p stimulated cardiomyocytes to re-enter the cell cycle. On the contrary, overexpression of miR-143-3p inhibited the mitosis of cardiomyocytes and abrogated cardiomyocyte mitosis induced by exposure to melatonin. Moreover, Yap and Ctnnd1 were identified as the target genes of miR-143-3p. In cardiomyocytes, inhibition of miR-143-3p increased the protein expression of Yap and Ctnnd1. Melatonin treatment also enhanced Yap and Ctnnd1 protein levels. Furthermore, Yap siRNA and Ctnnd1 siRNA attenuated melatonin-induced cell cycle re-entry of cardiomyocytes. We showed that the effect of melatonin on cardiomyocyte proliferation and cardiac regeneration was impeded by the melatonin receptor inhibitor luzindole. Silencing miR-143-3p abrogated the inhibition of luzindole on cardiomyocyte proliferation. In addition, both MT1 and MT2 siRNA could cancel the beneficial effects of melatonin on cardiomyocyte proliferation. Collectively, the results suggest that melatonin induces cardiomyocyte proliferation and heart regeneration after MI by regulating the miR-143-3p/Yap/Ctnnd1 signaling pathway, providing a new therapeutic strategy for cardiac regeneration.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Melatonina/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Miocitos Cardíacos/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Animales Recién Nacidos , Cateninas/metabolismo , Ciclo Celular/efectos de los fármacos , Células Cultivadas , Corazón/efectos de los fármacos , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT2/metabolismo , Regeneración/efectos de los fármacos , Proteínas Señalizadoras YAP , Catenina delta
7.
Sensors (Basel) ; 21(19)2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34641001

RESUMEN

Human activity recognition has been extensively used for the classification of occupational tasks. Existing activity recognition approaches perform well when training and testing data follow an identical distribution. However, in the real world, this condition may be violated due to existing heterogeneities among training and testing data, which results in degradation of classification performance. This study aims to investigate the impact of four heterogeneity sources, cross-sensor, cross-subject, joint cross-sensor and cross-subject, and cross-scenario heterogeneities, on classification performance. To that end, two experiments called separate task scenario and mixed task scenario were conducted to simulate tasks of electrical line workers under various heterogeneity sources. Furthermore, a support vector machine classifier equipped with domain adaptation was used to classify the tasks and benchmarked against a standard support vector machine baseline. Our results demonstrated that the support vector machine equipped with domain adaptation outperformed the baseline for cross-sensor, joint cross-subject and cross-sensor, and cross-subject cases, while the performance of support vector machine equipped with domain adaptation was not better than that of the baseline for cross-scenario case. Therefore, it is of great importance to investigate the impact of heterogeneity sources on classification performance and if needed, leverage domain adaptation methods to improve the performance.


Asunto(s)
Aprendizaje , Máquina de Vectores de Soporte , Humanos , Reconocimiento en Psicología
8.
Ecotoxicol Environ Saf ; 169: 551-563, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30476817

RESUMEN

Exposure to ambient fine particular matter (PM2.5) has been clearly associated with male reproductive disorders. However, very limited toxicological studies were carried out to investigate the potential mechanisms underlying the PM2.5-induced sperm quality decline. In the present study, we established a real time whole-body PM2.5 exposure mouse model to investigate the effects of PM2.5 on sperm quality and its potential mechanisms. Sixty male C57BL/6 mice were randomly subjected to three groups: filtered air group, unfiltered air group and concentrated air group. Half of the mice from each group were sacrificed for study when the exposure duration accumulated to 8 weeks and the rest of the mice were sacrificed when exposed for 16 weeks. Our results suggested that PM2.5 exposure could induce significant increases in circulating white blood cells and inflammation in lungs. PM2.5 exposure induced apparently DNA damages and histopathologic changes in testes. There were significantly decreased sperm densities of mice, which were paralleled with the down-regulated testosterone levels in testes tissue of mice after exposure to PM2.5 for 16 weeks. The numbers of motile sperms were decreased and sperms with abnormal morphology were increased after PM2.5 exposure in a time-depended and dose-depended manner. PM2.5 exposure significantly increased the expression of the major components of the NACHT, LRR and PYD domains-containing protein3 (NALP3) inflammasome, accompanied by the increased expression of miR-183/96/182 targeting FOXO1 in testes. The present data demonstrated that sperm quality decline induced by PM2.5 could be partly explained by the inflammatory reaction in testes which might be a consequence of systemic inflammation. The molecular mechanism was depended on the activation of NALP3 inflammasome accompanied by miR-183/96/182 targeting FOXO1 in testes.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Proteína Forkhead Box O1/metabolismo , Inflamasomas/metabolismo , MicroARNs/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Material Particulado/toxicidad , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Contaminantes Atmosféricos/análisis , Animales , Masculino , Ratones , Ratones Endogámicos C57BL , Tamaño de la Partícula , Material Particulado/análisis , Distribución Aleatoria , Espermatozoides/metabolismo , Espermatozoides/patología , Testículo/metabolismo , Testículo/patología
9.
Int J Qual Health Care ; 27(1): 31-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25487914

RESUMEN

OBJECTIVE: This research is designed to examine the impact of varying patient population distributions on the in-control performance of the risk-adjusted Bernoulli CUSUM chart. DESIGN: The in-control performance of the chart is compared based on sampling the Parsonnet scores with replacement from five realistic subsets of a given distribution. SETTINGS: Five patient mixes with different Parsonnet score distributions are created from a real patient population. MAIN OUTCOME MEASURES: The outcome measures for this research are the in-control average run lengths (ARLs) given varying patient populations. RESULTS: Our simulation results show that the in-control ARLs of the risk-adjusted Bernoulli CUSUM chart with fixed control limits and a given risk-adjustment equation vary significantly for different patient population distributions, and the in-control ARLs decrease as the mean of the Parsonnet scores increases. CONCLUSIONS: The simulation results imply that the control limits should vary based on the particular patient population of interest in order to control the in-control performance of the risk-adjusted Bernoulli CUSUM method.


Asunto(s)
Ajuste de Riesgo/métodos , Ajuste de Riesgo/normas , Factores de Edad , Sesgo , Simulación por Computador , Estado de Salud , Humanos , Modelos Estadísticos , Calidad de la Atención de Salud , Factores de Riesgo
10.
Ecol Evol ; 14(2): e10944, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38343574

RESUMEN

The order Tetraodontiformes are one of the most unique groups of teleostean fish, exhibiting highly derived and greatly diversified phenotypes. It is a difficult task for both professionals and nonprofessionals to accurately identify these species only according to morphological characteristics. DNA barcoding can identify species at the molecular level to overcome the limitations of morphological classification. In this study, we collected 616 specimens of pufferfish from the coastal waters of China. According to the morphological characteristics, they were preliminarily identified as 50 species. Further analysis using DNA barcodes identified these specimens as 46 species, belonging to 23 genera, 6 families. According to the species classification results of DNA barcoding, the three species identified by morphology as Takifugu pseudommus, Takifugu chinensis, and Takifugu rubripes should be the same species. Similarly, Lagocephalus wheeleri is the synonym of Lagocephalus spadiceus. Another important discovery of DNA barcoding analysis is that there are closer interspecific genetic distances within the genus Takifugu. If T. rubripes, T. pseudommus, and T. chinensis are taken as one species, the average interspecific to intraspecific genetic distance ratio of Takifugu is only 6.21 times, which does not reach the DNA barcoding threshold of more than 10 times proposed previously. Although the interspecific genetic distance in the genus Takifugu is relatively small, each species can be clustered into independent clades in the NJ tree. In conclusion, this study not only found that there are synonymous phenomena in the order Tetraodontiformes but also provided molecular evidence for the valid species names of Takifugu rubripes and Lagocephalus Spadiceus. The results can provide reliable DNA barcoding information for the identification of pufferfish species, help solve the problem of classification confusion in this order, and provide technical support for the identification of the original components of related commodities on the aquatic product market.

11.
J Glob Health ; 14: 04140, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38898796

RESUMEN

Background: There is increasing evidence on the link between environmental factors and myopia in children and adolescents, yet with inconsistent conclusions. We investigated the associations between socioeconomic inequalities and green space with myopia in school-aged students participating in the Tianjin Child and Adolescent Research of Eye (TCARE) study. Methods: We obtained data from a population-based dynamic cohort study conducted in Tianjin, China, in 2021 and followed up in 2022. We included 1 245 271 participants from 16 districts with an average age of 11.6 years (standard deviation = 3.3) in our analysis. We synthesized their area-level SES through a prediction model that combined economic, educational, and health care variables and assessed the greenness levels surrounding the school using the Normalized Difference Vegetation Index (NDVI) based on data obtained through satellite remote sensing. We performed generalised linear mixed effects analyses for each myopia outcome separately, with adjustments for students' sex, years of education completed, and the school's geographical location. Results: We observed that students living in low SES areas had the highest prevalence of myopia (60.7%) in the last screening in 2022, as well as a higher incidence of one-year myopia (26.4%) compared to those residing in middle SES areas (22.7%). With a 0.1 increase in the 250, 500, and 1000 m buffer NDVI, the prevalence of myopia dropped by 6.3% (odds ratio (OR) = 0.937; 95% confidence interval (CI) = 0.915, 0.960), 7.7% (OR = 0.923; 95% CI = 0.900, 0.946), and 8.7% (OR = 0.913; 95% CI = 0.889, 0.937), respectively. The interaction analysis showed that low SES and low greenness exacerbate the prevalence of myopia. Findings from longitudinal analyses consistently demonstrated a correlation between higher values of NDVI and a slower progression of myopia. These findings remained robust across sensitivity analyses, including for variables on parental myopia and students' behaviors. Conclusions: Exposure to green spaces could play a crucial role in slowing the progression of myopia among school-aged students. Myopia control policies should prioritise young populations residing in low SES areas with limited access to green spaces, as they face the highest potential risks.


Asunto(s)
Miopía , Factores Socioeconómicos , Estudiantes , Humanos , Miopía/epidemiología , Femenino , Masculino , China/epidemiología , Niño , Adolescente , Estudios de Cohortes , Estudiantes/estadística & datos numéricos , Prevalencia , Parques Recreativos/estadística & datos numéricos , Disparidades Socioeconómicas en Salud , Pueblos del Este de Asia
12.
Nat Commun ; 15(1): 2137, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459019

RESUMEN

Translational control is crucial for protein production in various biological contexts. Here, we use Ribo-seq and RNA-seq to show that genes related to oxidative phosphorylation are translationally downregulated during heart regeneration. We find that Nat10 regulates the expression of Uqcr11 and Uqcrb mRNAs in mouse and human cardiomyocytes. In mice, overexpression of Nat10 in cardiomyocytes promotes cardiac regeneration and improves cardiac function after injury. Conversely, treating neonatal mice with Remodelin-a Nat10 pharmacological inhibitor-or genetically removing Nat10 from their cardiomyocytes both inhibit heart regeneration. Mechanistically, Nat10 suppresses the expression of Uqcr11 and Uqcrb independently of its ac4C enzyme activity. This suppression weakens mitochondrial respiration and enhances the glycolytic capacity of the cardiomyocytes, leading to metabolic reprogramming. We also observe that the expression of Nat10 is downregulated in the cardiomyocytes of P7 male pig hearts compared to P1 controls. The levels of Nat10 are also lower in female human failing hearts than non-failing hearts. We further identify the specific binding regions of Nat10, and validate the pro-proliferative effects of Nat10 in cardiomyocytes derived from human embryonic stem cells. Our findings indicate that Nat10 is an epigenetic regulator during heart regeneration and could potentially become a clinical target.


Asunto(s)
Miocitos Cardíacos , Procesamiento Proteico-Postraduccional , Animales , Femenino , Humanos , Masculino , Ratones , Acetiltransferasas/metabolismo , Miocitos Cardíacos/metabolismo , Acetiltransferasas N-Terminal/metabolismo , ARN Mensajero/metabolismo , Porcinos
13.
Brain Cogn ; 83(3): 307-14, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24128658

RESUMEN

Mainstream theories about decision-making under risk suggest that risky decisions are made by choosing the option that offers the highest mathematical expectation. The present event-related potentials (ERPs) study investigated the neurocognitive mechanisms underlying risky choice by contrasting a preferential choice task with an expected value choice task. The ERP data revealed that (1) the computational difficulty, which would be expected to influence a compensatory process, affected the slow wave only when participants were forced to choose the option with the highest expectation; and that (2) the difference in the minimum outcome dimension between two options, which would be expected to be influential in a heuristic process, affected the P300 and slow wave when participants were asked to choose the preferred option. Our findings provide neural evidence that preferential choice is not based on an expectation computation and thus raised the question of whether expectation theories can provide an adequate description of individual risky decisions.


Asunto(s)
Conducta de Elección/fisiología , Potenciales Evocados/fisiología , Recompensa , Asunción de Riesgos , Adulto , Electroencefalografía/instrumentación , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Femenino , Humanos , Masculino , Conceptos Matemáticos , Probabilidad , Adulto Joven
14.
IISE Trans Occup Ergon Hum Factors ; 11(3-4): 123-135, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38536045

RESUMEN

OCCUPATIONAL APPLICATIONSMusculoskeletal disorders are prevalent among warehouse workers who engage in repetitive and dynamic tasks. To prevent such injuries, it is vital to identify the factors that influence fatigue in the upper extremities during these repetitive activities. Our study reveals that task factors, namely the bottle mass and picking rate, significantly influence upper extremity fatigue. In most cases, the fatigue indicator is a functional variable, meaning that the fatigue score or measurement is a curve captured over time, which could be modeled as a function. In this study, we demonstrate that functional data analysis tools, such as functional analysis of variance (FANOVA), prove more effective than traditional methods in specifying how task factors contribute to the development of fatigue in the upper extremities. Furthermore, since there are inherent differences among workers that could affect their fatigue development process, the data heterogeneity could be tackled by employing clustering methods.


Background: Preventing musculoskeletal disorders is a paramount safety concern for industries, with order pickers in warehouses being particularly vulnerable due to their repetitive and dynamic tasks. Understanding the factors contributing to upper-extremity fatigue in such settings is crucial. Purpose: This paper investigates the impact of task-related factors on two upper-extremity fatigue indicators: ratings of perceived fatigue and relative muscle strength. Several statistical approaches were used and compared in terms of their capability in eliciting these effects. Methods: Simulated over-shoulder, order-picking lab experiments were conducted under different combinations of two bottle loads and three picking paces. Fourteen participants, evenly distributed between genders, completed the experiment. A FANOVA was executed as the principal analytical approach, considering the functional nature of the two fatigue indicators measured over the work period. To underscore the benefits of considering the whole functional curve instead of discrete variables, we also conducted repeated-measures and two-way ANOVA as benchmark analyses. Results: FANOVA outcomes affirmed that both task factors (load and pace) significantly influenced both fatigue indicators. The FANOVA method identified larger effect sizes (0.11< ηp2 < 0.19) for both task factors compared to the conventional methods (0< ηp2 < 0.11), supporting the efficacy of FANOVA in identifying the importance of these factors. Conclusions: The FANOVA approach proved effective in detecting the impact of task factors on fatigue indicators, yielding superior results compared to conventional benchmark methods. To address participant heterogeneity, functional clustering and gender-based clustering were introduced into the FANOVA framework, both effectively mitigating this challenge. Notably, FANOVA with functional clusters had superior performance compared to the one with gender clustering, suggesting functional clustering as a more suitable method in overcoming participant heterogeneity.


Asunto(s)
Fatiga Muscular , Enfermedades Profesionales , Humanos , Extremidad Superior , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/prevención & control , Análisis de Varianza
15.
Percept Mot Skills ; 115(2): 439-42, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23265009

RESUMEN

In a recent paper, Stamps (2011a) reported findings on how two environmental properties, namely, boundary height and horizontal area within a boundary, influence impressions of enclosure. He found that the boundary height had a greater influence on impressions of enclosure than the horizontal area within a boundary. Enclosure correlated at 0.85 with boundary height and at -0.60 with horizontal area. This note suggests that environmental features are related not only to a concrete experiential variable but also to mental representations of abstract concepts.


Asunto(s)
Orientación , Reconocimiento Visual de Modelos , Percepción del Tamaño , Percepción Espacial , Femenino , Humanos , Masculino
16.
Appl Ergon ; 102: 103732, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35287084

RESUMEN

Existing ergonomic risk assessment tools require monitoring of multiple risk factors. To eliminate the direct observation, we investigated the effectiveness of an end-to-end framework that works with the data from a single wearable sensor. The framework is used to identify the performed task as the major contextual risk factor, and then estimate the task duration and number of repetitions as two main indicators of task intensity. For evaluation of the framework, we recruited 37 participants to complete 10 simulated work tasks in a laboratory setting. In testing, we achieved an average accuracy of 92% for task identification, 7.3% error in estimation of task duration, and 7.1% error for counting the number of task repetitions. Moreover, we showed the utility of the framework outputs in two ergonomic tools to estimate the risk of injury. Overall, we indicated the feasibility of using data from wearable sensors to automate the ergonomic risk assessment in workplaces.


Asunto(s)
Ciencia de los Datos , Dispositivos Electrónicos Vestibles , Ergonomía , Humanos , Factores de Riesgo , Lugar de Trabajo
17.
PLoS One ; 17(12): e0261765, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36490294

RESUMEN

Electrical line workers (ELWs) experience harsh environments, characterized by long shifts, remote operations, and potentially risky tasks. Wearables present an opportunity for unobtrusive monitoring of productivity and safety. A prerequisite to monitoring is the automated identification of the tasks being performed. Human activity recognition has been widely used for classification for activities of daily living. However, the literature is limited for electrical line maintenance/repair tasks due to task variety and complexity. We investigated how features can be engineered from a single wrist-worn accelerometer for the purpose of classifying ELW tasks. Specifically, three classifiers were investigated across three feature sets (time, frequency, and time-frequency) and two window lengths (4 and 10 seconds) to identify ten common ELW tasks. Based on data from 37 participants in a lab environment, two application scenarios were evaluated: (a) intra-subject, where individualized models were trained and deployed for each worker; and (b) inter-subject, where data was pooled to train a general model that can be deployed for new workers. Accuracies ≥ 93% were achieved for both scenarios, and increased to ≥96% with 10-second windows. Overall and class-specific feature importance were computed, and the impact of those features on the obtained predictions were explained. This work will contribute to the future risk mitigation of ELWs using wearables.


Asunto(s)
Actividades Cotidianas , Ciencia de los Datos , Humanos , Muñeca , Articulación de la Muñeca , Acelerometría
18.
Int J Biol Sci ; 18(7): 2980-2993, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35541894

RESUMEN

Photobiomodulation (PBM) has emerged as an alternative therapy involved in modulating a variety of biological effects. In this study, we verified whether PBM can affect cardiac physiological activity in mice through noninvasive irradiation using light-emitting diodes at a wavelength of 630 nm (LED-Red). We found that the PBM involved in regulating the repair of injured myocardium is wavelength-limited. LED-Red caused cardiomyocytes (CMs) that had exited the cell cycle to divide and proliferate again, and the cell proliferation ratio increased significantly with the accumulation of intracellular photopower. In addition, LED-Red promoted myocardial revascularization and myocardial regeneration, reduced the area of fibrosis in mice with myocardial infarction (MI), and thus improved cardiac contractile function. In regard to the mechanism, miRNA sequencing analysis showed that low-power LED-Red irradiation could induce differential changes in miRNAs in CMs. Among them, miR-136-5p was identified as a cardiac photo-sensitive miRNA and was obviously inhibited after stimulation, which produced a proliferation-promoting effect on CMs. Subsequent luciferase reporter assays confirmed the involvement of Ino80 as a binding target of miR-136-5p in the regulatory process of CM proliferation. Similarly, LED-Red irradiation elevated intracellular Ino80 expression. After knockdown of Ino80, the proliferation-promoting effect of LED-Red on CMs was inhibited. Collectively, this study demonstrates that LED-Red can promote CM proliferation by inhibiting cardiac photo-sensitive miRNA- miR-136-5p expression through targeting Ino80. The findings provided a new potential strategy for the treatment of ischemic cardiomyopathy (ICD).


Asunto(s)
Terapia por Luz de Baja Intensidad , MicroARNs , Infarto del Miocardio , Animales , Apoptosis , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Infarto del Miocardio/genética , Infarto del Miocardio/metabolismo , Infarto del Miocardio/terapia , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo
19.
Polymers (Basel) ; 14(15)2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35956720

RESUMEN

The latest advancements in cellulose and its derivatives are the subject of this study. We summarize the characteristics, modifications, applications, and properties of cellulose. Here, we discuss new breakthroughs in modified cellulose that allow for enhanced control. In addition to standard approaches, improvements in different techniques employed for cellulose and its derivatives are the subject of this review. The various strategies for synthetic polymers are also discussed. The recent advancements in polymer production allow for more precise control, and make it possible to make functional celluloses with better physical qualities. For sustainability and environmental preservation, the development of cellulose green processing is the most abundant renewable substance in nature. The discovery of cellulose disintegration opens up new possibilities for sustainable techniques. Based on the review of recent scientific literature, we believe that additional chemical units of cellulose solubility should be used. This evaluation will evaluate the sustainability of biomass and processing the greenness for the long term. It appears not only crucial to dissolution, but also to the greenness of any process.

20.
Nanoscale ; 13(36): 15324-15333, 2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-34494062

RESUMEN

Machine learning (ML) techniques have been recently employed to facilitate the development of novel two-dimensional (2D) materials. Among various synthesis approaches, chemical vapor deposition (CVD) has demonstrated tremendous potential in producing high-quality 2D flakes with good controllability, enabling large-scale production at a relatively low cost. Traditionally, the quality of CVD-grown samples can be manually evaluated based on optical images which is labor-intensive and time-consuming. In this paper, we explored a data-driven unsupervised quality assessment strategy based on image clustering via integrating self-organizing map (SOM) and k-means methods for optical image analysis of CVD-grown 2D materials. The high matching rate between the clustering results and material experts' labels indicated a good accuracy of the proposed clustering algorithm. The proposed unsupervised ML methodology will provide materials scientists with an effective tool kit for efficient evaluation of CVD-grown materials' quality and has a broad applicability for various material systems.

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