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1.
J Formos Med Assoc ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38331638

RESUMO

Acute mountain sickness (AMS) is initiated in response to a hypoxic and hypobaric environment at a high altitude. The precise prevalence of AMS in Jade Mountain climbers remained largely unknown, particularly data obtained from real medical consultations. An overnight stay at the Pai-Yun Lodge (3402 m) is usually required before an ascent of the Jade Mountain. Since 2004, a Pai-Yun Clinic has been established in the Pai-Yun Lodge. The Pai-Yun Clinic provided regular and emergency medical service every weekend. We conducted a retrospective study by using medical records from the Pai-Yun Clinic between 2018 and 2019. A total of 1021 patients were enrolled, with 56.2 % males. Different age groups were 3.2 %, 54.5 %, 37.9 %, and 4.4 % in <20, 20-39, 40-59, and ≥60 years, respectively. There were 582 (57.0 %) patients diagnosed to have AMS (230 [39.5 %] were mild type and 352 [60.5 %] were severe type). The factors associated with AMS development included young age, absence of climbing history (>3000 m) within the last 3 months, first climbing (>3000 m) experience, taking preventive medication, low oxygen saturation, and a high Lake Louise AMS score (LLAMSS). The factors associated with AMS severity included absence of taking preventive medication, low oxygen saturation, and a high LLAMSS. Approximately 15 % of Jade Mountain climbers needed medical service, of which 60 % had AMS. 60 % of patients with AMS must require oxygen supply or medication prescription. Oxygen saturation measure and LLAMSS evaluation are reasonable tools to predict the occurrence and severity of AMS on Jade Mountain.

2.
Ecotoxicol Environ Saf ; 212: 112018, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550076

RESUMO

The underlying mechanisms of microRNAs (miRNAs) in regulating nanoplastic toxicity are still largely unclear in organisms. In nanopolystyrene (NPS) exposed Caenorhabditis elegans, the expression of mir-76 (a neuronal miRNA) was significantly decreased, and the mir-76 mutant was resistant to the toxicity of NPS. The aim of this study was to determine the molecular basis of mir-76 in controlling NPS toxicity in nematodes. The mir-76 mutation increased expression of glb-10 encoding a globin protein in NPS (1 µg/L) exposed nematodes. Exposure to NPS (1-100 µg/L) increased the glb-10 expression, and the glb-10(RNAi) worm was susceptible to NPS toxicity in inducing reactive oxygen species (ROS) production and in decreasing locomotion behavior. Using ROS production and locomotion behavior as endpoints, mutation of glb-10 inhibited resistance of mir-76 mutant to NPS toxicity, and neuronal overexpression of mir-76 inhibited the resistance to NPS toxicity in nematodes overexpressing neuronal glb-10 containing 3' untranslated region (3'UTR). Thus, GLB-10 functioned as a target of mir-76 in the neurons to regulate the NPS toxicity. Moreover, a signaling cascade of HRG-7-HRG-5 required for the control of heme homeostasis was identified to function downstream of neuronal GLB-10 to regulate the NPS toxicity. In this signaling cascade, the neuronal HRG-7 regulated the NPS toxicity by antagonizing function of intestinal HRG-5. Furthermore, in the intestine, HRG-5 controlled NPS toxicity by inhibiting functions of hypoxia-inducible transcriptional factor HIF-1 and transcriptional factor ELT-2. Our results highlight the crucial function of heme homeostasis related signaling in regulating the NPS toxicity in organisms.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos dos fármacos , Heme/metabolismo , Homeostase , MicroRNAs/genética , Nanoestruturas/toxicidade , Poliestirenos/toxicidade , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Intestinos/efeitos dos fármacos , Nanoestruturas/química , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Poliestirenos/química , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
3.
Int J Neuropsychopharmacol ; 23(6): 356-365, 2020 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-32215560

RESUMO

BACKGROUND: Disturbed self-regulation, taste reward, as well as somatosensory and visuospatial processes were thought to drive binge eating and purging behaviors that characterize bulimia nervosa. Although studies have implicated a central role of the striatum in these dysfunctions, there have been no direct investigations on striatal functional connectivity in bulimia nervosa from a network perspective. METHODS: We calculated the functional connectivity of striatal subregions based on the resting-state functional Magnetic Resonance Imaging data of 51 bulimia nervosa patients and 53 healthy women. RESULTS: Compared with the healthy women, bulimia nervosa patients showed increased positive functional connectivity in bilateral striatal nuclei and thalamus for nearly all of the striatal subregions, and increased negative functional connectivity in bilateral primary sensorimotor cortex and occipital areas for both ventral striatum and putamen subregions. Only for the putamen subregions, we observed reduced negative functional connectivity in the prefrontal (bilateral superior and middle frontal gyri) and parietal (right inferior parietal lobe and precuneus) areas. Several striatal connectivities with occipital and primary sensorimotor cortex significantly correlated with the severity of bulimia. CONCLUSIONS: The findings indicate bulimia nervosa-related alterations in striatal functional connectivity with the dorsolateral prefrontal cortex supporting self-regulation, the subcortical striatum and thalamus involved in taste reward, as well as the visual occipital and sensorimotor regions mediating body image, which contribute to our understanding of neural circuitry of bulimia nervosa and encourage future therapeutic developments for bulimia nervosa by modulating striatal pathway.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Bulimia Nervosa/diagnóstico por imagem , Comportamento Alimentar , Imageamento por Ressonância Magnética , Descanso , Adolescente , Adulto , Encéfalo/fisiopatologia , Bulimia Nervosa/fisiopatologia , Bulimia Nervosa/psicologia , Estudos de Casos e Controles , Feminino , Humanos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Valor Preditivo dos Testes , Adulto Jovem
4.
Bipolar Disord ; 21(8): 774-784, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407477

RESUMO

OBJECTIVE: Misdiagnosis of bipolar disorder (BD) as unipolar disorder (UD) may cause improper treatment strategy to be chosen, especially in the early stages of disease. The aim of this study was to characterize alterations in specific brain networks for depressed patients who transformed into BD (tBD) from UD. METHOD: The module allegiance from resting-fMRI by applying a multilayer modular method was estimated in 99 patients (33 tBD, 33 BD, 33 UD) and 33 healthy controls (HC). A classification model was trained on tBD and UD patients. HC was used to explore the functional declination patterns of BD, tBD, and UD. RESULTS: Based on our classification model, difference mainly reflected in default-mode network (DMN). Compared with HC, both BD and tBD focused on the difference of somatomotor network (SMN), while UD on the abnormity of DMN. The patterns of brain network between patients with BD and tBD were well-overlapped, except for cognitive control network (CCN). CONCLUSION: The functional declination of internal interaction in DMN was suggested to be useful for the identification of BD from UD in the early stage. The higher recruitment of DMN may predispose patients to depressive states, while higher recruitment of SMN makes them more sensitive to external stimuli and prone to mania. Furthermore, CCN may be a critical network for identifying different stages of BD, suggesting that the onset of mania in depressed patients is accompanied by CCN related cognitive impairments.


Assuntos
Transtorno Bipolar/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Adulto , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/psicologia , Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Depressão , Transtorno Depressivo Maior/fisiopatologia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Descanso , Medição de Risco
5.
J Magn Reson Imaging ; 45(4): 1135-1143, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27533068

RESUMO

PURPOSE: To detect the consecutive variations of the internetwork interactions over time, which helps to discover the underlying dysfunction of depressive disorders. Abnormal interactions of resting-state functional networks have been reported in depression. However, little is known regarding the dynamics of how these crucial networks interact and the disease-related dysfunction. MATERIALS AND METHODS: Functional magnetic resonance imaging data at 3.0T in the resting state were acquired from 20 depressed patients and 20 healthy controls. Twelve resting-state networks were extracted by group-independent component analysis, and their interactions were calculated through a sliding windowed Granger causality model analysis. The acquired effective connectivity matrices were used to construct multislice networks with modular structures that were detected via a multislice community detection method. RESULTS: No significant differences were observed in the modularity and total module numbers between the depressed patients and the healthy controls. The P values were 0.133 with a confidence interval (-0.0001 0.0093) and 0.136 with a confidence interval (-0.30 0.90), respectively. However, the depressed patients exhibited decreased flexibility of the salience network (SN) compared with the controls (P = 0.048, corrected, with a confidence interval 0.0068 0.066). CONCLUSION: SN was inclined to participate less in the multiple brain functional modules across the resting time in depression, and infrequently changed its modular allegiance. These findings support the potential importance of the SN in the neuropathological mechanism of depression. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:1135-1143.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Descanso , Adulto Jovem
6.
Anal Bioanal Chem ; 407(18): 5343-51, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25925857

RESUMO

The endoplasmic reticulum (ER), a multifunctional organelle, plays a central role in cellular signaling, development, and stress response. Dysregulation of ER homeostasis has been associated with human diseases, such as cancer, inflammation, and diabetes. A broad spectrum of stressful stimuli including hypoxia as well as a variety of pharmacological agents can lead to the ER stress response. In this study, we have developed a stable ER stress reporter cell line that stably expresses a ß-lactamase reporter gene under the control of the ER stress response element (ESRE) present in the glucose-regulated protein, 78 kDa (GRP78) gene promoter. This assay has been optimized and miniaturized into a 1536-well plate format. In order to identify clinically used drugs that induce ER stress response, we screened approximately 2800 drugs from the NIH Chemical Genomics Center Pharmaceutical Collection (NPC library) using a quantitative high-throughput screening (qHTS) platform. From this study, we have identified several known ER stress inducers, such as 17-AAG (via HSP90 inhibition), as well as several novel ER stress inducers such as AMI-193 and spiperone. The confirmed drugs were further studied for their effects on the phosphorylation of eukaryotic initiation factor 2α (eIF2α), the X-box-binding protein (XBP1) splicing, and GRP78 gene expression. These results suggest that the ER stress inducers identified from the NPC library using the qHTS approach could shed new lights on the potential therapeutic targets of these drugs.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Animais , Linhagem Celular , Chaperona BiP do Retículo Endoplasmático , Genes Reporter , Células HeLa , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Humanos , Elementos de Resposta , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , beta-Lactamases/genética , beta-Lactamases/metabolismo
7.
Zhong Yao Cai ; 37(2): 224-7, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25095340

RESUMO

OBJECTIVE: To establish an HPLC fingerprint of Eriobotrya japonica flower. METHODS: 13 batches of Eriobotrya japonica flowers from different habitats were analyzed by HPLC with ursolic acid as reference substance. The chromatographic condition was performed on Alltech Apollo C18 column (250 mm x 4.6 mm, 5 microm), eluted with mobile phase containing methanol and 0.1% glacial acetic acid in gradient mode. The flow rate was 0.5 mL/min and the detection wavelength was set at 210 nm. The temperature of column was 20 degrees C. RESULT: The HPLC fingerprint of Eriobotrya japonica flower had been established. There were 17 common peaks, two of which were identified by reference substances. 13 batches of sample from different habitats can be distinguished from their fingerprints. CONCLUSION: This method is reasonable and reliable, which can be used for quality evaluation of Eriobotrya japonica flower.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Eriobotrya/química , Flores/química , China , Medicamentos de Ervas Chinesas/normas , Controle de Qualidade , Reprodutibilidade dos Testes , Triterpenos/química , Ácido Ursólico
8.
Artigo em Inglês | MEDLINE | ID: mdl-38976468

RESUMO

Traditional DNA storage technologies rely on passive filtering methods for error correction during synthesis and sequencing, which result in redundancy and inadequate error correction. Addressing this, the Low Quality Sequence Filter (LQSF) was introduced, an innovative method employing deep learning models to predict high-risk sequences. The LQSF approach leverages a classification model trained on error-prone sequences, enabling efficient pre-sequencing filtration of low-quality sequences and reducing time and resources in subsequent stages. Analysis has demonstrated a clear distinction between high and low-quality sequences, confirming the efficacy of the LQSF method. Extensive training and testing were conducted across various neural networks and test sets. The results showed all models achieving an AUC value above 0.91 on ROC curves and over 0.95 on PR curves across different datasets. Notably, models such as Alexnet, VGG16, and VGG19 achieved a perfect AUC of 1.0 on the Original dataset, highlighting their precision in classification. Further validation using Illumina sequencing data substantiated a strong correlation between model scores and sequence error-proneness, emphasizing the model's applicability. The LQSF method marks a significant advancement in DNA storage technology, introducing active sequence filtering at the encoding stage. This pioneering approach holds substantial promise for future DNA storage research and applications.

9.
Med Biol Eng Comput ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922373

RESUMO

The exponential growth in data volume has necessitated the adoption of alternative storage solutions, and DNA storage stands out as the most promising solution. However, the exorbitant costs associated with synthesis and sequencing impeded its development. Pre-compressing the data is recognized as one of the most effective approaches for reducing storage costs. However, different compression methods yield varying compression ratios for the same file, and compressing a large number of files with a single method may not achieve the maximum compression ratio. This study proposes a multi-file dynamic compression method based on machine learning classification algorithms that selects the appropriate compression method for each file to minimize the amount of data stored into DNA as much as possible. Firstly, four different compression methods are applied to the collected files. Subsequently, the optimal compression method is selected as a label, as well as the file type and size are used as features, which are put into seven machine learning classification algorithms for training. The results demonstrate that k-nearest neighbor outperforms other machine learning algorithms on the validation set and test set most of the time, achieving an accuracy rate of over 85% and showing less volatility. Additionally, the compression rate of 30.85% can be achieved according to k-nearest neighbor model, more than 4.5% compared to the traditional single compression method, resulting in significant cost savings for DNA storage in the range of $0.48 to 3 billion/TB. In comparison to the traditional compression method, the multi-file dynamic compression method demonstrates a more significant compression effect when compressing multiple files. Therefore, it can considerably decrease the cost of DNA storage and facilitate the widespread implementation of DNA storage technology.

10.
Int J Ophthalmol ; 17(5): 924-931, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766340

RESUMO

AIM: To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children. METHODS: This is a prospective, randomized control, intervention study. A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this study. The whole randomization method was adopted to include classes as a group according to 1:1 randomized control. Classrooms in the control group were illuminated by usual light, and classrooms in the intervention group were illuminated by artificial natural light. All students received uncorrected visual acuity and best-corrected visual acuity measurement, non-cycloplegic autorefraction, ocular biometric examination, slit lamp and strabismus examination. Three-year follow-up, the students underwent same procedures. Myopia was defined as spherical equivalent refraction ≤ -0.50 D and uncorrected visual acuity <20/20. RESULTS: There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±0.53y. The three-year cumulative incidence rate of myopia was 26.4% (207 incident cases among 784 eligible participants at baseline) in the control group and 21.2% (164 incident cases among 774 eligible participants at baseline) in the intervention group [difference of 5.2% (95%CI, 3.7% to 10.1%); P=0.035]. There was also a significant difference in the three-year change in spherical equivalent refraction for the control group (-0.81 D) compared with the intervention group [-0.63 D; difference of 0.18 D (95%CI, 0.08 to 0.28 D); P<0.001]. Elongation of axial length was significantly different between in the control group (0.77 mm) and the intervention group [0.72 mm; difference of 0.05 mm (95%CI, 0.01 to 0.09 mm); P=0.003]. CONCLUSION: Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.

11.
Chembiochem ; 14(7): 827-35, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23585185

RESUMO

Epigenetics is an emerging field that demands selective cell-permeable chemical probes to perturb, especially in vivo, the activity of specific enzymes involved in modulating the epigenetic codes. Coactivator-associated arginine methyltransferase 1 (CARM1) is a coactivator of estrogen receptor α (ERα), the main target in human breast cancer. We previously showed that twofold overexpression of CARM1 in MCF7 breast cancer cells increased the expression of ERα-target genes involved in differentiation and reduced cell proliferation, thus leading to the hypothesis that activating CARM1 by chemical activators might be therapeutically effective in breast cancer. Selective, potent, cell-permeable CARM1 activators will be essential to test this hypothesis. Here we report the development of a cell-based, time-resolved (TR) FRET assay that uses poly(A) binding protein 1 (PABP1) methylation to monitor cellular activity of CARM1. The LanthaScreen TR-FRET assay uses MCF7 cells expressing GFP-PABP1 fusion protein through BacMam gene delivery system, methyl-PABP1 specific antibody, and terbium-labeled secondary antibody. This assay has been validated as reflecting the expression and/or activity of CARM1 and optimized for high throughput screening to identify CARM1 allosteric activators. This TR-FRET platform serves as a generic tool for functional screening of cell-permeable, chemical modulators of CARM1 for elucidation of its in vivo functions.


Assuntos
Neoplasias da Mama/enzimologia , Transferência Ressonante de Energia de Fluorescência , Proteína-Arginina N-Metiltransferases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Fatores de Tempo
12.
Artigo em Zh | MEDLINE | ID: mdl-24148961

RESUMO

OBJECTIVE: To study the occupational exposure limit of dimethoxymethane (DMM) in workplace air. METHODS: Literature research was conducted on DMM; information on its physicochemical properties, toxicology, and occupational epidemiology was collected. Upon analyzing these data, an occupational exposure limit of DMM in workplace air was proposed according to the guidelines and principles of developing occupational exposure limits for harmful factors in workplaces. RESULTS: A total of 165 air samples were collected from DMM manufacturers, 14 of which had a DMM concentration over 3000 mg/m(3), accounting for 8.48% of all samples. Compared with the control group, the exposed employees had a significantly increased incidence of discomfort symptoms when exposed to more than 6000 mg/m(3) DMN (P < 0.01).No significant differences in the constituent ratios of abnormal results in physical examinations were found between the exposure groups and control group (P > 0.05). CONCLUSION: We recommend to set the permissible concentration-time weighed average to 3100 mg/m(3) as the occupational exposure limit of DMM in workplace air in China. This occupational exposure limit standard meets the relevant requirements of toxicology and occupational epidemiology, as well as fits well with our country's current economical and technological levels. This standard has high applicability in China's domestic settings.


Assuntos
Poluentes Ocupacionais do Ar/análise , Éteres Metílicos/análise , Exposição Ocupacional/análise , China , Humanos , Exposição por Inalação , Níveis Máximos Permitidos , Local de Trabalho
13.
Materials (Basel) ; 16(8)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37109954

RESUMO

The rise in the connectivity of the fractures is a key task in oil/gas and geothermal exploitation systems. Natural fractures widely exist in underground reservoir sandstone, while the mechanical behavior of rock with fractures subjected to hydro-mechanical coupling loads is far from clear. This paper employed comprehensive experiments and numerical simulations to investigate the failure mechanism and permeability law for sandstone specimens with T-shaped faces subjected to hydro-mechanical coupling loads. The effects of crack closure stress, crack initiation stress, strength, and axial strain stiffness of the specimens under different fracture inclination angles are discussed, and the evolution processes of permeability are obtained. The results show that secondary fractures are created around the pre-existing T-shaped fractures through tensile, shear, or mixed modes. The fracture network causes an increase in the permeability of the specimen. T-shaped fractures have a more significant effect on the strength of the specimens than water. The peak strengths of T-shaped specimens decreased by 34.89%, 33.79%, 46.09%, 39.32%, 47.23%, 42.76%, and 36.02%, respectively, compared with intact specimen without water pressure. With the increase in deviatoric stress, the permeability of T-shaped sandstone specimens decreases first, then increases, reaching its maximum value when macroscopic fractures are formed, after which the stress suddenly decreases. When the prefabricated T-shaped fracture angle is 75°, the corresponding permeability of the sample at failure is maximum, with a value of 15.84 × 10-16 m2. The failure process of the rock is reproduced through numerical simulations, in which the influence of damage and macroscopic fractures on permeability is discussed.

14.
Biochem Soc Trans ; 40(5): 1158-62, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22988882

RESUMO

Mutations in LRRK2 (leucine-rich repeat kinase 2) have been linked to inherited forms of PD (Parkinson's disease). Substantial pre-clinical research and drug discovery efforts have focused on LRRK2 with the hope that small-molecule inhibitors of the enzyme may be valuable for the treatment or prevention of the onset of PD. The pathway to develop therapeutic or neuroprotective agents based on LRRK2 function (i.e. kinase activity) has been facilitated by the development of both biochemical and cell-based assays for LRRK2. LRRK2 is phosphorylated on Ser910, Ser935, Ser955 and Ser973 in the N-terminal domain of the enzyme, and these sites of phosphorylation are likely to be regulated by upstream enzymes in an LRRK2 kinase-activity-dependent manner. Knowledge of these phosphorylation sites and their regulation can be adapted to high-throughput-screening-amenable platforms. The present review describes the utilization of LRRK2 phosphorylation as indicators of enzyme inhibition, as well as how such assays can be used to deconvolute the pathways in which LRRK2 plays a role.


Assuntos
Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sítios de Ligação/efeitos dos fármacos , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Relação Estrutura-Atividade
15.
Artigo em Inglês | MEDLINE | ID: mdl-35805753

RESUMO

Flourishing indicates one's emotional status and functioning level and is essential for adolescents' further development. Adolescents' social media use has been rising, with various potential effects on their development. Therefore, in this study, we shifted the emphasis from a traditional deficit-based approach to a strength-based approach by exploring how social comparison and social media usage influence Chinese adolescents' flourishing. Altogether, 786 Chinese adolescents aged 12-19 years completed a self-report questionnaire. The results indicate that (1) both social media social comparison of ability (SCA) and social media social comparison of opinion (SCO) have no significant effect on Chinese adolescents' flourishing; (2) integration into social routine has a positive indirect effect on the relationship between social media social comparison and flourishing; and (3) social integration and emotional connection negatively affect the relationship between social media social comparison and flourishing. These findings highlight the interaction between social media social comparison and social media usage. Furthermore, the results of this study clarify that the potentially harmful effect of social media usage on adolescents' flourishing is not determined by the frequency or time spent on using social media, but how much adolescents are connected to or invested in social media.


Assuntos
Comportamento do Adolescente , Mídias Sociais , Adolescente , Comportamento do Adolescente/psicologia , Desenvolvimento do Adolescente , China , Humanos , Comparação Social
16.
Nanoscale ; 14(12): 4762-4769, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35275145

RESUMO

Graphene with in-plane nanoholes, named holey graphene, shows great potential in electrochemical applications due to its fast mass transport and improved electrochemical activity. Scalable nanomanufacturing of holey graphene is generally based on chemical etching using hydrogen peroxide to form through-the-thickness nanoholes on the basal plane of graphene. In this study, we probe into the fundamental mechanisms of nanohole formation under peroxide etching via an integrated experimental and computational effort. The research results show that the growth of nanoholes during the etching of graphene oxide is achieved by a three-stage reduction-oxidation-reduction procedure. First, it is demonstrated that vacancy defects are formed via a partial reduction-based pretreatment. Second, hydrogen peroxide reacts preferentially with the edge-sites of defect areas on graphene oxide sheets, leading to the formation of various oxygen-containing functional groups. Third, the carbon atoms around the defects are removed along with the neighboring carbon atoms via reduction. By advancing the understanding of process mechanisms, we further demonstrate an improved nanomanufacturing strategy, in which graphene oxide with a high density of defects is introduced for peroxide etching, leading to enhanced nanohole formation.

17.
Healthcare (Basel) ; 10(10)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36292485

RESUMO

Owing to the COVID-19 pandemic, many countries' physicians in the world have used telehealth to visit patients via telehealth. The study aimed to integrate the theory of planned behavior (TPB), the technology acceptance model (TAM), and self-determination theory (SDT) to explore the adoption behavior of a telehealth system. A convenient sample of residents was drawn from the population of Nantou County in Taiwan and analyzed via structural equation modeling. The findings revealed that attitude, perceived behavioral control, perceived usefulness, and perceived autonomy support jointly have significantly positive effects on continuance intention. Results also confirmed that perceived autonomy support, perceived ease of use, and perceived usefulness jointly have significantly positive effects on attitude. Furthermore, this study also showed that a crucial mediators' role is played by perceived ease of use, perceived usefulness, and attitude. The conclusions and practical implications of the research will hopefully provide health organizations and institutions with some innovative insights and foresights, which in turn will promote better practices and services of telehealth technology.

18.
J Xray Sci Technol ; 19(1): 23-33, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21422587

RESUMO

The real-time imaging is important in automatic successive inspection with micro-computerized tomography (micro-CT). Generally, the size of the detector is chosen according to the most probable size of the measured object to acquire all the projection data. Given enough imaging area and imaging resolution of X-ray detector, the detector is larger than specimen projection area, which results in redundant data in the Sinogram. The process of real-time micro-CT is computation-intensive because of the large amounts of source and destination data. The speed of the reconstruction algorithm can't always meet the requirements of real-time applications. A preprocessing method called adaptive region of interest (AROI), which detects the object's boundaries automatically to focus the active Sinogram regions, is introduced into the analytical reconstruction algorithm in this paper. The AROI method reduces the volume of the reconstructing data and thus directly accelerates the reconstruction process. It has been further shown that image quality is not compromised when applying AROI, while the reconstruction speed is increased as the square of the ratio of the sizes of the detector and the specimen slice. In practice, the conch reconstruction experiment indicated that the process is accelerated by 5.2 times with AROI and the imaging quality is not degraded. Therefore, the AROI method improves the speed of analytical micro-CT reconstruction significantly.


Assuntos
Intensificação de Imagem Radiográfica/métodos , Microtomografia por Raio-X/métodos , Imagens de Fantasmas , Ecrans Intensificadores para Raios X
19.
ACS Nano ; 15(7): 12057-12068, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34170681

RESUMO

Selective deposition and preferential alignment of two-dimensional (2D) nanoparticles on complex and flexible three-dimensional (3D) substrates can tune material properties and enrich structural versatility for broad applications in wearable health monitoring, soft robotics, and human-machine interfaces. However, achieving precise and scalable control of the morphology of layer-structured nanomaterials is challenging, especially constructing hierarchical architectures consistent from nanoscale alignment to microscale patterning to complex macroscale landscapes. This work demonstrated a scalable and straightforward hybrid 3D printing method for orientational alignment and positional patterning of 2D MXene nanoparticles. This process involved (i) surface topology design via microcontinuous liquid interface production (µCLIP) and (ii) directed assembly of MXene flakes via capillarity-driven direct ink writing (DIW). With well-managed surface patterning geometry and printing ink quality control, the surface microchannels constrained MXene suspensions and leveraged microforces to facilitate preferential alignment of MXene sheets via layer-by-layer additive depositions. The printed devices displayed multifunctional properties, i.e., anisotropic conductivity and piezoresistive sensing with a wide sensing range, high sensitivity, fast response time, and mechanical durability. Our fabrication technique shows enormous potential for rapid, digital, scalable, and low-cost manufacturing of hierarchical structures, especially for micropatterning and aligning 2D nanoparticles not easily accessible through conventional processing methods.

20.
Ecol Evol ; 11(22): 16266-16279, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34824826

RESUMO

Colonies are the basic geometric building blocks of coral reefs. However, the forming regulations of both colonies and reefs are still not understood adequately. Therefore, in this study, we reconstructed 25 samples using high-resolution micro-computed tomography to investigate coral growth patterns and parameters. Our skeleton and canal reconstructions revealed the characteristics of different coral species, and we further visualized the growth axes and growth rings to understand the coral growth directions. We drew a skeleton grayscale map and calculated the coral skeleton void ratios to ascertain the skeletal diversity, devising a method to quantify coral growth. On the basis of the three-dimensional (3D) reconstructions and growth parameters, we investigated the growth strategies of different coral species. This research increases the breadth of knowledge on how reef-building corals grow their colonies, providing information on reef-forming regulations. The data in this paper contain a large amount of coral growth information, which can be used in further research on reef-forming patterns under different conditions. The method used in this study can also be applied to animals with porous skeletons.

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