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1.
Front Aging Neurosci ; 16: 1410544, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193492

RESUMEN

Introduction: Alzheimer's disease (AD) is highly heterogeneous, with substantial individual variabilities in clinical progression and neurobiology. Amyloid deposition has been thought to drive cognitive decline and thus a major contributor to the variations in cognitive deterioration in AD. However, the clinical heterogeneity of patients with early symptomatic AD (mild cognitive impairment or mild dementia due to AD) already with evidence of amyloid abnormality in the brain is still unknown. Methods: Participants with a baseline diagnosis of mild cognitive impairment or mild dementia, a positive amyloid-PET scan, and more than one follow-up Alzheimer's Disease Assessment Scale-Cognitive Subscale-13 (ADAS-Cog-13) administration within a period of 5-year follow-up were selected from the Alzheimer's Disease Neuroimaging Initiative database (n = 421; age = 73±7; years of education = 16 ± 3; percentage of female gender = 43%; distribution of APOE4 carriers = 68%). A non-parametric k-means longitudinal clustering analysis in the context of the ADAS-Cog-13 data was performed to identify cognitive subtypes. Results: We found a highly variable profile of cognitive decline among patients with early AD and identified 4 clusters characterized by distinct rates of cognitive progression. Among the groups there were significant differences in the magnitude of rates of changes in other cognitive and functional outcomes, clinical progression from mild cognitive impairment to dementia, and changes in markers presumed to reflect neurodegeneration and neuronal injury. A nomogram based on a simplified logistic regression model predicted steep cognitive trajectory with an AUC of 0.912 (95% CI: 0.88 - 0.94). Simulation of clinical trials suggested that the incorporation of the nomogram into enrichment strategies would reduce the required sample sizes from 926.8 (95% CI: 822.6 - 1057.5) to 400.9 (95% CI: 306.9 - 516.8). Discussion: Our findings show usefulness in the stratification of patients in early AD and may thus increase the chances of finding a treatment for future AD clinical trials.

2.
Bioresour Technol ; 411: 131295, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39155017

RESUMEN

The cultivation of microalgae is significantly influenced by light intensity and utilization efficiency. This study developed a modified Cornet (M-Cornet) model to assess the distribution of light intensity and flux in microalgae cultivation systems. Algal biofilm cultivation represents a more concentrated approach of algal suspension cultivation. Both follow the M-Cornet model and exhibit the same growth rates when cultured under identical conditions. Algal pigments and morphologies greatly impact the light absorption and scattering, resulting in light attenuation in intensity, penetration distance and light flux distribution. Algae varieties exhibit diverse light flux characteristics. 37% - 90% of the incident light is absorbed, of which, 80% to 90% is dissipated as heat. 10% to 63% of the incident light is scattered off the photobioreactor. The overall light utilization efficiency ranges 6% to 13%. The light footprint using the M-Cornet model offers valuable insights for photobioreactors designing and cultivation operating.

3.
Clin Transl Med ; 14(8): e1791, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39113233

RESUMEN

BACKGROUND: Mutations in several translation initiation factors are closely associated with premature ovarian insufficiency (POI), but the underlying pathogenesis remains largely unknown. METHODS AND RESULTS: We generated eukaryotic translation initiation factor 5 (Eif5) conditional knockout mice aiming to investigate the function of eIF5 during oocyte growth and follicle development. Here, we demonstrated that Eif5 deletion in mouse primordial and growing oocytes both resulted in the apoptosis of oocytes within the early-growing follicles. Further studies revealed that Eif5 deletion in oocytes downregulated the levels of mitochondrial fission-related proteins (p-DRP1, FIS1, MFF and MTFR) and upregulated the levels of the integrated stress response-related proteins (AARS1, SHMT2 and SLC7A1) and genes (Atf4, Ddit3 and Fgf21). Consistent with this, Eif5 deletion in oocytes resulted in mitochondrial dysfunction characterized by elongated form, aggregated distribution beneath the oocyte membrane, decreased adenosine triphosphate content and mtDNA copy numbers, and excessive accumulation of reactive oxygen species (ROS) and mitochondrial superoxide. Meanwhile, Eif5 deletion in oocytes led to a significant increase in the levels of DNA damage response proteins (γH2AX, p-CHK2 and p-p53) and proapoptotic proteins (PUMA and BAX), as well as a significant decrease in the levels of anti-apoptotic protein BCL-xL. CONCLUSION: These findings indicate that Eif5 deletion in mouse oocytes results in the apoptosis of oocytes within the early-growing follicles via mitochondrial fission defects, excessive ROS accumulation and DNA damage. This study provides new insights into pathogenesis, genetic diagnosis and potential therapeutic targets for POI. KEY POINTS: Eif5 deletion in oocytes leads to arrest in oocyte growth and follicle development. Eif5 deletion in oocytes impairs the translation of mitochondrial fission-related proteins, followed by mitochondrial dysfunction. Depletion of Eif5 causes oocyte apoptosis via ROS accumulation and DNA damage response pathway.


Asunto(s)
Apoptosis , Daño del ADN , Ratones Noqueados , Oocitos , Especies Reactivas de Oxígeno , Animales , Especies Reactivas de Oxígeno/metabolismo , Ratones , Oocitos/metabolismo , Daño del ADN/genética , Femenino , Apoptosis/genética , Dinámicas Mitocondriales/genética , Factores de Iniciación de Péptidos/genética , Factores de Iniciación de Péptidos/metabolismo , Factor 5A Eucariótico de Iniciación de Traducción , Folículo Ovárico/metabolismo , Folículo Ovárico/crecimiento & desarrollo
4.
Bioresour Technol ; 406: 131062, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38964514

RESUMEN

Acquiring lipid-producing strains of Saccharomyces cerevisiae is necessary for producing high-value palmitoleic acid. This study sought to generate oleaginous S. cerevisiae mutants through a combination of zeocin mutagenesis and fluorescence-activated cell sorting, and then to identify key mutations responsible for enhanced lipid accumulation by multi-omics sequencing. Following three consecutive rounds of mutagenesis and sorting, a mutant, MU310, with the lipid content of 44%, was successfully obtained. Transcriptome and targeted metabolome analyses revealed that a coordinated response involving fatty acid precursor biosynthesis, nitrogen metabolism, pentose phosphate pathway, ethanol conversion, amino acid metabolism and fatty acid ß-oxidation was crucial for promoting lipid accumulation. The carbon fluxes of acetyl-CoA and NADPH in lipid biosynthesis were boosted in these pathways. Certain transcriptional regulators may also play significant roles in modulating lipid biosynthesis. Results of this study provide high-quality resource for palmitoleic acid production and deepen the understanding of lipid synthesis in yeast.


Asunto(s)
Lípidos , Mutagénesis , Saccharomyces cerevisiae , Ácidos Grasos/metabolismo , Ácidos Grasos Monoinsaturados , Citometría de Flujo , Metabolismo de los Lípidos , Lípidos/biosíntesis , Metaboloma , Multiómica , Mutación , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Transcriptoma/genética
5.
J Org Chem ; 89(15): 10572-10581, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39038277

RESUMEN

A protocol for selective and efficient synthesis of symmetrical and unsymmetrical m-terphenyls is presented among aryl acetylene and DMSO in the presence of KOH and methanol. In this reaction, two molecules of aryl acetylene contribute four carbons, and DMSO, as a dual carbon donor, provides two carbons to a new aromatic ring. This protocol can be tolerated for the electron-donating or disubstituted phenylacetylenes as well as the heterocyclic acetylene derivatives.

6.
Heliyon ; 10(12): e33053, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39027449

RESUMEN

Ulcerative Colitis(UC) is a chronic intestinal inflammation affecting the intestines, yet its underlying causes remain unclear. In recent decades, the global prevalence of UC has been on the rise, leading to an increasing demand for therapeutic drugs with minimal side effects. Huan Kui Le (HKL), a traditional Chinese medicine compound, has demonstrated promising efficacy when combined with Lactobacillus acidophilus (Lac.) for UC intervention. However, the precise therapeutic mechanism of this combination remains unknown. The study focused on understanding the mechanisms of UC by examining the effects of Lac. and HKL (LH) treatment. The outcomes discovered that the disruption of gut microbiota, triggered by the activation of the NLRP3 inflammasome, plays a crucial role in UC development. This disruption exacerbates UC symptoms by causing disturbances in inflammatory cytokines and mucosal permeability. We investigated the dynamic changes following the application of this treatment using 16S rRNA sequencing, HE, WB, IHC, and ELISA. Compared with the UC group, LH treatment reduced colon pathological injury, improved colon length, and decreased IL-1 ß serum levels. Furthermore, it restored the expression of TJs and preserved mucosal barrier integrity. LH treatment also mitigated colon injury by attenuating the expression of pyroptosis-related genes and proteins, such as NLRP3 and Caspase-1. Additionally, LH treatment altered the gut microbiota's microecology, characterized by a reduction in pathogenic bacteria abundance like Escherichia-shigella and an increase in beneficial bacteria abundance like Akkermansia and Erysipelatoclostridium. Overall, our findings indicate that LH therapy may be associated with intestinal barrier repair, inflammasome inhibition, and gut microbiota regulation, suggesting its potential as a UC treatment.

7.
Pharmaceuticals (Basel) ; 17(7)2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-39065745

RESUMEN

Inulin may be a promising therapeutic molecule for treating non-alcoholic fatty liver disease (NAFLD). However, the underlying mechanisms of its therapeutic activity remain unclear. To address this issue, a high-fat-diet-induced NAFLD mouse model was developed and treated with inulin. The NAFLD phenotype was evaluated via histopathological analysis and biochemical parameters, including serum levels of alanine aminotransferase, aspartate aminotransferase, liver triglycerides, etc. A serum metabolomics study was conducted using ultra-performance liquid chromatography coupled with tandem mass spectrometry. The results revealed that inulin mitigated NAFLD symptoms such as histopathological changes and liver cholesterol levels. Through the serum metabolomics study, 347 differential metabolites were identified between the model and control groups, and 139 differential metabolites were identified between the inulin and model groups. Additionally, 48 differential metabolites (such as phosphatidylserine, dihomo-γ-linolenic acid, L-carnitine, and 13-HODE) were identified as candidate targets of inulin and subjected to pathway enrichment analysis. The results revealed that these 48 differential metabolites were enriched in several metabolic pathways such as fatty acid biosynthesis and cardiolipin biosynthesis. Taken together, our results suggest that inulin might attenuate NAFLD partially by modulating 48 differential metabolites and their correlated metabolic pathways, constituting information that might help us find novel therapies for NAFLD.

8.
Anal Chim Acta ; 1316: 342870, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38969414

RESUMEN

A plasmonic tilted fiber Bragg grating (TFBG)-based sensor for the detection of calcium ion (Ca2+) was proposed and demonstrated experimentally. Hydrogel material was synthesized by utilizing hydrogen bond recombination between cellulose nanocrystals (CNC) and polyvinyl alcohol (PVA). Sodium alginate (SA) was incorporated into this hydrogel material, resulting in a composite membrane with specific binding properties for Ca2+. The membrane was applied as a coating on the surface of a gold-coated TFBG. The CNC/PVA-SA modified gold on the TFBG surface enhanced the localized refractive index changes caused by variations of Ca2+ concentrations. The experimental results demonstrated an impressive limit of detection (LOD) of approximately 0.025 fM, which is five orders of magnitude better than the current LODs of similar Ca2+ sensors. And the proposed Ca2+ sensor exhibited a wide dynamic range of 10-16 M to 10-6 M.

9.
Int J Biol Sci ; 20(9): 3480-3496, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38993560

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common cause of chronic liver-related morbidity and mortality. Though high fructose intake is acknowledged as a metabolic hazard, its role in the etiology of MASLD requires further clarification. Here, we demonstrated that high dietary fructose drives MASLD development and promotes MASLD progression in mice, and identified Usp2 as a fructose-responsive gene in the liver. Elevated USP2 levels were detected in the hepatocytes of MASLD mice; a similar increase was observed following fructose exposure in primary hepatocytes and mouse AML12 cells. Notably, hepatocytes overexpressing USP2 presented with exaggerated lipid accumulation and metabolic inflammation when exposed to fructose. Conversely, USP2 knockdown mitigated these fructose-induced changes. Furthermore, USP2 was found to activate the C/EBPα/11ß-HSD1 signaling, which further impacted the equilibrium of cortisol and cortisone in the circulation of mice. Collectively, our findings revealed the role of dietary fructose in MASLD pathogenesis and identified the USP2-mediated C/EBPα/ 11ß-HSD1 signaling as a potential target for the management of MASLD.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1 , Fructosa , Ubiquitina Tiolesterasa , Animales , Ratones , Fructosa/efectos adversos , Ubiquitina Tiolesterasa/metabolismo , Ubiquitina Tiolesterasa/genética , Masculino , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Ratones Endogámicos C57BL , Transducción de Señal , Hígado Graso/metabolismo , Hepatocitos/metabolismo , Hígado/metabolismo , Endopeptidasas/metabolismo
10.
Artículo en Inglés | MEDLINE | ID: mdl-38976462

RESUMEN

Ultrasound Localization Microscopy (ULM), an emerging medical imaging technique, effectively resolves the classical trade-off between resolution and penetration inherent in traditional ultrasound imaging, opening up new avenues for noninvasive observation of the microvascular system. However, traditional microbubble tracking methods encounter various practical challenges. These methods typically entail multiple processing stages, including intricate steps like pairwise correlation and trajectory optimization, rendering real-time applications unfeasible. Furthermore, existing deep learning-based tracking techniques neglect the temporal aspects of microbubble motion, leading to ineffective modeling of their dynamic behavior. To address these limitations, this study introduces a novel approach called the Gated Recurrent Unit (GRU)-based Multitasking Temporal Neural Network (GRU-MT). GRU-MT is designed to simultaneously handle microbubble trajectory tracking and trajectory optimization tasks. Additionally, we enhance the nonlinear motion model initially proposed by Piepenbrock et al. to better encapsulate the nonlinear motion characteristics of microbubbles, thereby improving trajectory tracking accuracy. In this study, we perform a series of experiments involving network layer substitutions to systematically evaluate the performance of various temporal neural networks, including Recurrent Neural Networks (RNN), Long Short-Term Memory (LSTM), GRU, Transformer, and its bidirectional counterparts, on the microbubble trajectory tracking task. Concurrently, the proposed method undergoes qualitative and quantitative comparisons with traditional microbubble tracking techniques. The experimental results demonstrate that GRU-MT exhibits superior nonlinear modeling capabilities and robustness, both in simulation and in vivo dataset. Additionally, it achieves reduced trajectory tracking errors in shorter time intervals, underscoring its potential for efficient microbubble trajectory tracking. Model code is open-sourced at https://github.com/zyt-Lib/GRU-MT.

11.
Cell Prolif ; : e13718, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39044637

RESUMEN

Eukaryotic translation initiation factor 2 subunit 2 (EIF2S2), a subunit of the heterotrimeric G protein EIF2, is involved in the initiation of translation. Our findings demonstrate that the depletion of Eif2s2 in premeiotic germ cells causes oocyte arrest at the pachytene and early diplotene stages at 1 day postpartum (dpp) and 5 dpp, respectively, and eventually leads to oocyte apoptosis and failure of primordial follicle formation. Further studies reveal that Eif2s2 deletion downregulates homologous recombination-related and mitochondrial fission-related protein levels, and upregulates the integrated stress response-related proteins and mRNA levels. Consistently, Eif2s2 deletion significantly decreases the expression of dictyate genes and compromises mitochondrial function, characterized by elongated shapes, decreased ATP levels and mtDNA copy number, along with an excessive accumulation of reactive oxygen species (ROS) and mitochondrial superoxide. Furthermore, DNA damage response and proapoptotic protein levels increase, while anti-apoptotic protein levels decrease in Eif2s2-deleted mice. An increase in oocytes with positive cleaved-Caspase-3 and TUNEL signals, alongside reduced Lamin B1 intensity, further indicates oocyte apoptosis. Collectively, Eif2s2 deletion in premeiotic germ cells causes oocyte meiotic arrest at the early diplotene stage by impairing homologous recombination, and eventually leads to oocyte apoptosis mainly through the downregulation of mitochondrial fission-related proteins, ROS accumulation and subsequent DNA damage.

12.
Org Lett ; 26(28): 6018-6023, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38968445

RESUMEN

Herein, decarboxylative C(sp3)-Sb coupling of aliphatic carboxylic acid derivatives with chlorostibines to access alkylstibines has been achieved. This catalyst-, ligand-, and base-free approach using zinc as a reductant affords various kinds of benzyldiarylstibines and other monoalkyldiarylstibines and tolerates various functional groups, including chlorine, bromine, hydroxyl, amide, sulfone, and cyano groups. The late-stage modification and the gram-scale experiments illustrate its potential application.

13.
bioRxiv ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38746443

RESUMEN

Physical exercise represents a primary defense against age-related cognitive decline and neurodegenerative disorders like Alzheimer's disease (AD). To impartially investigate the underlying mechanisms, we conducted single-nucleus transcriptomic and chromatin accessibility analyses (snRNA-seq and ATAC-seq) on the hippocampus of mice carrying AD-linked NL-G-F mutations in the amyloid precursor protein gene (APPNL-G-F) following prolonged voluntary wheel-running exercise. Our study reveals that exercise mitigates amyloid-induced changes in both transcriptomic expression and chromatin accessibility through cell type-specific transcriptional regulatory networks. These networks converge on the activation of growth factor signaling pathways, particularly the epidermal growth factor receptor (EGFR) and insulin signaling, correlating with an increased proportion of immature dentate granule cells and oligodendrocytes. Notably, the beneficial effects of exercise on neurocognitive functions can be blocked by pharmacological inhibition of EGFR and the downstream phosphoinositide 3-kinases (PI3K). Furthermore, exercise leads to elevated levels of heparin-binding EGF (HB-EGF) in the blood, and intranasal administration of HB-EGF enhances memory function in sedentary APPNL-G-F mice. These findings offer a panoramic delineation of cell type-specific hippocampal transcriptional networks activated by exercise and suggest EGF-related growth factor signaling as a druggable contributor to exercise-induced memory enhancement, thereby suggesting therapeutic avenues for combatting AD-related cognitive decline.

14.
J Fungi (Basel) ; 10(5)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38786673

RESUMEN

Phytophthora sojae is a type of pathogenic oomycete that causes Phytophthora root stem rot (PRSR), which can seriously affect the soybean yield and quality. To subvert immunity, P. sojae secretes a large quantity of effectors. However, the molecular mechanisms regulated by most P. sojae effectors, and their host targets remain unexplored. Previous studies have shown that the expression of PsAvh113, an effector secreted by Phytophthora sojae, enhances viral RNA accumulations and symptoms in Nicotiana benthamiana via VIVE assay. In this study, we analyzed RNA-sequencing data based on disease symptoms in N. benthamiana leaves that were either mocked or infiltrated with PVX carrying the empty vector (EV) and PsAvh113. We identified 1769 differentially expressed genes (DEGs) dependent on PsAvh113. Using stricter criteria screening and Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) analysis of DEGs, we found that 38 genes were closely enriched in response to PsAvh113 expression. We selected three genes of N. benthamiana (NbNAC86, NbMyb4, and NbERF114) and found their transcriptional levels significantly upregulated in N. benthamiana infected with PVX carrying PsAvh113. Furthermore, individual silencing of these three genes promoted P. capsici infection, while their overexpression increased resistance to P. capsici in N. benthamiana. Our results show that PsAvh113 interacts with transcription factors NbMyb4 and NbERF114 in vivo. Collectively, these data may help us understand the pathogenic mechanism of effectors and manage PRSR in soybeans.

15.
Heliyon ; 10(9): e30401, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38756578

RESUMEN

The trend of male celebrities endorsing female products is increasing. However, research is lacking on whether this influence is due to the positive emotions generated by the male celebrity's attractiveness or the peer pressure due to mass purchases by the celebrity's fans, and how these effects differ across products with different attributes. This study aims to fill the gap in the existing literature by investigating the influence of male endorsers on female consumers purchase intention, and to deepen the understanding of the mechanisms by which attractiveness and conformity jointly influence purchase decisions. This study used a mixed-design text experiment to investigate the impact of male endorsers' attractiveness and conformity on female college students' positive product attitude and purchase intention for gender-neutral product, female skincare product, and female intimate product, based on the Theory of Planned Behaviour (TPB). The data collected from 456 female college students were analyzed using bootstrap analysis. The study found that both male endorsers' attractiveness and conformity can enhance female college students' positive product attitude and promote their purchase intention for gender-neutral product. However, for female skincare product, male endorsers' attractiveness affects their positive product attitude and purchase intention. Nevertheless, when conformity was present, attractiveness no longer had an effect. Furthermore, for individuals with high levels of loneliness, attractiveness had a detrimental effect on their positive product attitude. On the other hand, conformity had a positive effect by promoting positive product attitude and increasing purchase intention. For female's intimate product, attractiveness did not affect positive product attitude and purchase intention, but the positive effect of conformity remained significant, and both relationships were not moderated by loneliness. It enhances our comprehension of the intricate dynamics underlying the influence of male celebrity endorsements on consumer purchasing decisions, and also offers theoretical justification for the selection of male endorsers for diverse female product.

16.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38610244

RESUMEN

Acoustic imaging technology has the advantages of non-contact and intuitive positioning. It is suitable for the rapid positioning of defects such as the mechanical loosening, discharge, and DC bias of power equipment. However, the existing research lacks the optimization design of microphone array topology. The acoustic frequency domain characteristics of typical power equipment are elaborately sorted out. After that, the cut-off frequencies of acoustic imaging instruments are determined, to meet the needs of the full bandwidth test requirements. Through a simulation calculation, the circular array is demonstrated to be the optimal shape. And the design parameters affect the imaging performance of the array to varying degrees, indicating that it is difficult to obtain the optimal array topology by an exhaustive method. Aimed at the complex working conditions of power equipment, a topology optimization design method of an acoustic imaging array for power equipment is proposed, and the global optimal solution of microphone array topology is obtained. Compared with the original array, the imaging performance of the improved LF and HF array is promoted by 54% and 49%, respectively. Combined with the simulation analysis and laboratory test, it is verified that the improved array can not only accurately locate the single sound source but also accurately identify the main sound source from the interference of the contiguous sound source.

17.
J Therm Biol ; 121: 103828, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38604115

RESUMEN

Heating, Ventilation, and Air Conditioning (HVAC) systems in high-speed trains (HST) are responsible for consuming approximately 70% of non-operational energy sources, yet they frequently fail to ensure provide adequate thermal comfort for the majority of passengers. Recent advancements in portable wearable sensors have opened up new possibilities for real-time detection of occupant thermal comfort status and timely feedback to the HVAC system. However, since occupant thermal comfort is subjective and cannot be directly measured, it is generally inferred from thermal environment parameters or physiological signals of occupants within the HST compartment. This paper presents a field test conducted to assess the thermal comfort of occupants within HST compartments. Leveraging physiological signals, including skin temperature, galvanic skin reaction, heart rate, and ambient temperature, we propose a Predicted Thermal Comfort (PTC) model for HST cabin occupants and establish an intelligent regulation model for the HVAC system. Nine input factors, comprising physiological signals, individual physiological characteristics, compartment seating, and ambient temperature, were formulated for the PTS model. In order to obtain an efficient and accurate PTC prediction model for HST cabin occupants, we compared the accuracy of different subsets of features trained by Machine Learning (ML) models of Random Forest, Decision Tree, Vector Machine and K-neighbourhood. We divided all the predicted feature values into four subsets, and did hyperparameter optimisation for each ML model. The HST compartment occupant PTC prediction model trained by Random Forest model obtained 90.4% Accuracy (F1 macro = 0.889). Subsequent sensitivity analyses of the best predictive models were then performed using SHapley Additive explanation (SHAP) and data-based sensitivity analysis (DSA) methods. The development of a more accurate and operationally efficient thermal comfort prediction model for HST occupants allows for precise and detailed feedback to the HVAC system. Consequently, the HVAC system can make the most appropriate and effective air supply adjustments, leading to improved satisfaction rates for HST occupant thermal comfort and the avoidance of energy wastage caused by inaccurate and untimely predictive feedback.


Asunto(s)
Aprendizaje Automático , Temperatura Cutánea , Humanos , Aire Acondicionado/instrumentación , Aire Acondicionado/métodos , Frecuencia Cardíaca , Respuesta Galvánica de la Piel , Sensación Térmica , Temperatura , Masculino
18.
Proc Natl Acad Sci U S A ; 121(13): e2313334121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38498717

RESUMEN

Multiple facets of global change affect the earth system interactively, with complex consequences for ecosystem functioning and stability. Simultaneous climate and biodiversity change are of particular concern, because biodiversity may contribute to ecosystem resistance and resilience and may mitigate climate change impacts. Yet, the extent and generality of how climate and biodiversity change interact remain insufficiently understood, especially for the decomposition of organic matter, a major determinant of the biosphere-atmosphere carbon feedbacks. With an inter-biome field experiment using large rainfall exclusion facilities, we tested how drought, a common prediction of climate change models for many parts of the world, and biodiversity in the decomposer system drive decomposition in forest ecosystems interactively. Decomposing leaf litter lost less carbon (C) and especially nitrogen (N) in five different forest biomes following partial rainfall exclusion compared to conditions without rainfall exclusion. An increasing complexity of the decomposer community alleviated drought effects, with full compensation when large-bodied invertebrates were present. Leaf litter mixing increased diversity effects, with increasing litter species richness, which contributed to counteracting drought effects on C and N loss, although to a much smaller degree than decomposer community complexity. Our results show at a relevant spatial scale covering distinct climate zones that both, the diversity of decomposer communities and plant litter in forest floors have a strong potential to mitigate drought effects on C and N dynamics during decomposition. Preserving biodiversity at multiple trophic levels contributes to ecosystem resistance and appears critical to maintain ecosystem processes under ongoing climate change.


Asunto(s)
Sequías , Ecosistema , Biodiversidad , Bosques , Hojas de la Planta , Carbono
19.
BMC Health Serv Res ; 24(1): 227, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383405

RESUMEN

BACKGROUND: Improving the job engagement of health professionals can effectively enhance the quality of their medical services. However, few studies have investigated whether and how perceived professional benefits affect job engagement. Based on resource conservation theory, this study explored the effect of the influence of perceived professional benefits on job engagement, and also examined the mediating role of psychological availability and the moderating role of future perceived professional benefits. METHODS: A cross-sectional study was conducted in six tertiary hospitals and seven secondary hospitals in Liu Panshui, a city in western China. A total of 1,406 valid questionnaires were obtained and analysed by using correlation analysis, hierarchical regression analysis, and bootstrap tests. RESULT: The study found a significant positive association between health professionals' perceived professional benefits and their job engagement. Additionally, psychological availability was found to mediate this relationship. Future perceived professional benefits not only positively moderate this relationship between perceived professional benefits on health professionals' psychological availability but also positively moderate the mediating role of psychological availability between perceived professional benefits and job engagement. CONCLUSION: Improving health professionals' perceived professional benefits can enhance their job engagement by increasing their psychological availability. However, for health professionals with low future perceived professional benefits, this improvement may disappear. Therefore, it is important to enhance both their current and future perceived professional benefits to improve their job engagement.


Asunto(s)
Agotamiento Profesional , Satisfacción en el Trabajo , Humanos , Estudios Transversales , Personal de Salud/psicología , Encuestas y Cuestionarios , Centros de Atención Terciaria
20.
ACS Omega ; 9(7): 7958-7966, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38405544

RESUMEN

As a greenhouse gas with strong global warming potential, the use of SF6 needs to be reduced as much as possible. Researching environmentally friendly insulation (EFI) gases to replace SF6 in power electrical equipment is an effective way to reduce its usage. CF3SO2F/N2, as a newly proposed EFI gas, has certain potential to replace SF6. Compatibility of CF3SO2F/N2 gas with rubber sealing materials commonly used in electrical equipment is still unknown. In this article, the compatibility of CF3SO2F/N2 with the ethylene-propylene-diene monomer (EPDM) and chloroprene rubber (CR) was investigated experimentally. It was found that CF3SO2F/N2 would slightly decompose under the influence of EPDM and CR rubber under certain conditions. The surface morphology of EPDM changed slightly under the influence of CF3SO2F/N2, and it was similar to the influence of SF6. While the surface morphology of CR deteriorated significantly with obvious defects. The mechanical properties of EPDM were not significantly affected by CF3SO2F, which is similar to the influence of SF6. But CR was affected greatly by CF3SO2F gas. Permanent deformation compression and surface morphology are two effective indicators for characterizing the compatibility between gas and rubber sealing materials. This research provides a reference for the application of CF3SO2F/N2 as a new EFI gas in power equipment.

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