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1.
Langmuir ; 40(13): 6940-6948, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38507744

RESUMO

Flexible electrothermal films are crucial for protecting equipment and systems in cold weather, such as ice blockages in natural gas pipelines and icing on aircraft wings. Therefore, a flexible electric heater is one of the essential devices in industrial operations. One of the main challenges is to develop flexible electrothermal films with low operating voltage, high steady-state temperature, and good mechanical stability. In this study, a flexible electrothermal film based on graphene-patterned structures was manufactured by combining the laser induction method and the transfer printing process. The grid structure design provides accurate real-time monitoring for the application of electrothermal films and shows potential in solving problems related to deicing and clearing ice blockages in pipelines. The flexible electrothermal film can reach a high heating temperature of 165 °C at 15 V and exhibits sufficient heating stability. By employing a simple and efficient method to create a flexible, high-performance electrothermal film, we provide a reliable solution for deicing and monitoring applications.

2.
Qual Life Res ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008142

RESUMO

OBJECTIVE: This study was to evaluate measurement properties of the Chinese version of the Brief Inventory of Perceived Stress (BIPS-C) and confirm possible solutions for measuring the constructs underlying perceived stress. METHODS: A total of 1356 community residents enrolled and were randomly split into two halves. The first half was used to explore the underlying constructs of the BIPS-C by exploratory graph analysis (EGA) and the second half was used to compare and confirm the constructs by confirmatory factor analysis (CFA). RESULTS: The EGA identified a one-factor model of the BIPS-C with an accuracy of 99.3%. One-factor, three-factor, second-order, and bifactor models were compared by CFAs. The bifactor model with one general and three specific factors was found to be the most adequate [comparative fit index (CFI) = 0.990; Tucker-Lewis index (TLI) = 0.979; root mean square error of approximation (RMSEA) = 0.058] and was superior to the other models. The related bifactor indices showed a stronger existence of the general factor. The bifactor model of the BIPS-C also showed adequate internal consistency with McDonald's omega and omega subscales ranging from moderate to strong (0.677-0.869). CONCLUSION: The BIPS-C demonstrates sufficient measurement properties for assessing general perceived stress.

3.
BMC Psychiatry ; 24(1): 553, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123135

RESUMO

BACKGROUND: The Nightmare Distress Questionnaire (NDQ), known and commonly used for its adequate psychometric properties, is the most widely used instrument for the measurement of nightmare distress. This study aimed to assess the psychometric properties of a newly translated Arabic version of the Nightmare Distress Questionnaire (NDQ-AV). METHODS: A total of 546 Lebanese adolescents was recruited for this study and completed the NDQ-AV, the Insomnia Severity Index (ISI), and the eight-item Depression, Anxiety and Stress Scale (DASS-8). RESULTS: The results of the exploratory factor analysis (EFA) and the confirmatory factor analysis (CFA) supported both a one-factor model and a two-factor model of the NDQ-AV, with the latter consisting of seven items within both factors. The first factor was referred to as the "general nightmare distress and coping" while the second was named "nightmare impact and perception". The reliability of the scale was excellent (α = 0.930 and ω = 0.915). Moreover, measurement invariance was shown across gender, demonstrating that this measure performs consistently for both men and women. Additionally, the NDQ-AV scores exhibited excellent reliability alongside factorial and concurrent validity. CONCLUSION: In conclusion, these results support the psychometric validity of the Arabic version of the NDQ. The availability of the NDQ-AV is expected to facilitate the understanding of nightmare distress within the Lebanese context.


Assuntos
Sonhos , Psicometria , Humanos , Masculino , Feminino , Adolescente , Líbano , Reprodutibilidade dos Testes , Análise Fatorial , Sonhos/psicologia , Inquéritos e Questionários/normas , Angústia Psicológica , Escalas de Graduação Psiquiátrica/normas , Estresse Psicológico/psicologia , Estresse Psicológico/diagnóstico , Depressão/psicologia , Depressão/diagnóstico , Ansiedade/psicologia , Ansiedade/diagnóstico
4.
BMC Psychiatry ; 24(1): 517, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039478

RESUMO

BACKGROUND: Depression and anxiety symptoms among medical students are often a concern. The Patient Health Questionnaire-Four (PHQ-4), an important tool for depression and anxiety screening, is commonly used and easy to administer. This study aimed to assess and update the longitudinal measurement invariance and psychometric properties of the simplified Chinese version. METHODS: A three-wave longitudinal survey was conducted among healthcare students using the PHQ-4. Structural validity was based on one-factor, two-factor, and second-order factor models, construct validity was based on the Self-Rated Health Questionnaire (SRHQ), Sleep Quality Questionnaire (SQQ), and Rosenberg Self-Esteem Scale (RSES), and longitudinal measurement invariance (LMI), internal consistency, and test-retest reliability were based on structural consistency across three time points. RESULTS: The results of the confirmatory factor analysis indicated that two-factor model was the best fit, and LMI was supported at three time points. Inter-factor, factor-total, and construct validity correlations of the PHQ-4 were acceptable. Additionally, Cronbach's alpha, McDonald's omega, and the intraclass correlation coefficient demonstrated acceptable/moderate to excellent reliability of the PHQ-4. CONCLUSIONS: This study adds new longitudinal evidence that the Chinese version of the PHQ-4 has promising LMI and psychometric properties. Such data lends confidence to the routine and the expanded use of the PHQ-4 for routine screening of depression and anxiety in Chinese healthcare students.


Assuntos
Ansiedade , Depressão , Questionário de Saúde do Paciente , Psicometria , Humanos , China , Feminino , Masculino , Estudos Longitudinais , Reprodutibilidade dos Testes , Depressão/psicologia , Depressão/diagnóstico , Ansiedade/psicologia , Ansiedade/diagnóstico , Adulto , Adulto Jovem , Estudantes de Medicina/psicologia , Análise Fatorial , Inquéritos e Questionários/normas
5.
Gen Comp Endocrinol ; 355: 114563, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830459

RESUMO

Investigating the principles of fish fat deposition and conducting related research are current focal points in fish nutrition. This study explores the endocrine regulation of LEAP2 and GHSR1a in zebrafish by constructing mutantmodels andexamining the effects of the endocrine factors LEAP2 and its receptor GHSR1a on zebrafish growth, feeding, and liver fat deposition. Compared to the wild type (WT), the mutation of LEAP2 results in increased feeding and decreased swimming in zebrafish. The impact is more pronounced in adult female zebrafish, characterized by increased weight, length, width, and accumulation of lipid droplets in the liver.Incontrast, deficiency in GHSR1a significantly reduces the growth of male zebrafish and markedly decreases liver fat deposition.These research findings indicate the crucial roles of LEAP2 and GHSR1a in zebrafish feeding, growth, and intracellular fat metabolism. This study, for the first time, investigated the endocrine metabolic regulation functions of LEAP2 and GHSR1a in the model organism zebrafish, providing initial insights into their effects and potential mechanisms on zebrafish fat metabolism.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Metabolismo dos Lipídeos , Receptores de Grelina , Peixe-Zebra , Animais , Feminino , Masculino , Sistemas CRISPR-Cas , Mutação , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo
6.
Sheng Li Xue Bao ; 68(3): 255-64, 2016 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-27350198

RESUMO

The effective connectivity of default mode network (DMN) and its change after taking methylphenidate (MPH) were investigated in this study based on resting-state functional magnetic resonance imaging. Dynamic causal modeling (DCM) was applied to compare the effective connectivity between the conditions of taking MPH and placebo for 18 healthy male volunteers. Started with the network structural basis provided by a recent literature, endogenous low frequency fluctuation signals (0.01-0.08 Hz) of each node of DMN were taken as the driving input, and thirty-two possible models were designed according to the modulation effect of MPH on different connections between nodes. Model fitting and Bayesian model selection were performed to find the winning model and corresponding parameters. Our results indicated that the effective connectivity from medial prefrontal cortex (MPFC) to posterior cingulated cortex (PCC), from left/right inferior parietal lobule (L/RIPL) to MPFC, and from RIPL to PCC were excitatory, whereas the connectivity from LIPL to PCC was inhibitory. Further t-test statistics on connectivity parameters found that MPH significantly reduced the link from RIPL to MPFC in DMN (t = 2.724, P = 0.016) and changed the weak excitatory state to inhibitory state. However, it had no significant effect on other connections. In all, our results demonstrated that MPH modulates the effective connectivity within DMN in resting state.


Assuntos
Imageamento por Ressonância Magnética , Teorema de Bayes , Feminino , Giro do Cíngulo , Humanos , Masculino , Metilfenidato , Lobo Parietal , Córtex Pré-Frontal
7.
Hum Brain Mapp ; 36(10): 3878-89, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26173095

RESUMO

Benign epilepsy with centrotemporal spikes (BECTS) is often associated with neural circuit dysfunction, particularly during the transient active state characterized by interictal epileptiform discharges (IEDs). Little is known, however, about the functional neural circuit abnormalities in BECTS without IEDs, or if such abnormalities could be used to differentiate BECTS patients without IEDs from healthy controls (HCs) for early diagnosis. To this end, we conducted resting-state functional magnetic resonance imaging (RS-fMRI) and simultaneous Electroencephalogram (EEG) in children with BECTS (n = 43) and age-matched HC (n = 28). The simultaneous EEG recordings distinguished BECTS with IEDs (n = 20) from without IEDs (n = 23). Intrinsic brain activity was measured in all three groups using the amplitude of low frequency fluctuation at rest. Compared to HC, BECTS patients with IEDs exhibited an intrinsic activity abnormality in the thalamus, suggesting that thalamic dysfunction could contribute to IED emergence while patients without IEDs exhibited intrinsic activity abnormalities in middle frontal gyrus and superior parietal gyrus. Using multivariate pattern classification analysis, we were able to differentiate BECTS without IEDs from HCs with 88.23% accuracy. BECTS without epileptic transients can be distinguished from HC and BECTS with IEDs by unique regional abnormalities in resting brain activity. Both transient abnormalities as reflected by IEDs and chronic abnormalities as reflected by RS-fMRI may contribute to BECTS development and expression. Intrinsic brain activity and multivariate pattern classification techniques are promising tools to diagnose and differentiate BECTS syndromes. Hum Brain Mapp 36:3878-3889, 2015. © 2015 Wiley Periodicals, Inc.


Assuntos
Encéfalo/fisiopatologia , Epilepsia Rolândica/diagnóstico , Biomarcadores , Criança , Eletroencefalografia , Epilepsia/fisiopatologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos , Lobo Parietal/fisiopatologia , Reprodutibilidade dos Testes , Tálamo/fisiopatologia
8.
Cancer Cell Int ; 14(1): 72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25278811

RESUMO

BACKGROUND: Transforming growth factor beta (TGF-ß) plays major roles in tumorigenesis by regulating cell growth, epithelial-to-mesenchymal transition (EMT), migration/invasion and metastasis. The epithelial markers E-cadherin, claudin-3 and claudin-4, commonly decreased in human adenocarcinomas are actually up regulated during ovarian carcinogenesis. In human ovarian cancer TGF-ß1 may either suppress or promote tumor progression, but whether other TGF-ß isoforms (TGF-ß2 and TGF-ß3) exert similar effects is not known. METHODS: In this study we investigated the ability of the TGF-ß isoforms (TGF-ß1-3) to induce proliferation and migration by BrdU labeling, scratch wound and trans-filter migration assays in the human serous adenocarcinoma cell-line NIH-OVCAR3. Transepithelial resistance was measured and EMT observed by light-microscopy. Expression of adherens-, tight-junction and EMT-related transcription factors was analyzed by qRT-PCR and immunoblotting. RESULTS: All TGF-ß isoforms dose-dependently inhibited NIH-OVCAR3 cell growth, stimulated tumor cell migration with similar efficiency. The mesenchymal marker N-cadherin and claudin-1 expression was induced and occludin down regulated. However, migrating cells retained an epithelial shape and E-cadherin expression. The E-cadherin repressor SNAIL mRNA levels remained low independently of TGF-ß1-3 treatment while ZEB1 expression was enhanced. CONCLUSIONS: TGF-ß1, TGF-ß2 and TGF-ß3 promote migration of NIH-OVCAR3 ovarian cancer cells independently of cell proliferation and without conversion to a complete EMT phenotype. Epithelial ovarian cancer commonly metastasis to the surrounding tissue or inside the peritoneum rather than invading blood vessels to set distance metastasis. Our result raises the question whether ovarian cancer primarily spread via collective migration than via single cell invasion.

9.
J Comput Biol ; 30(9): 1019-1033, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37702623

RESUMO

In the field of drug development and repositioning, the prediction of drug-disease associations is a critical task. A recently proposed method for predicting drug-disease associations based on graph convolution relies heavily on the features of adjacent nodes within the homogeneous network for characterizing information. However, this method lacks node attribute information from heterogeneous networks, which could hardly provide valuable insights for predicting drug-disease associations. In this study, a novel drug-disease association prediction model called DAHNGC is proposed, which is based on a graph convolutional neural network. This model includes two feature extraction methods that are specifically designed to extract the attribute characteristics of drugs and diseases from both homogeneous and heterogeneous networks. First, the DropEdge technique is added to the graph convolutional neural network to alleviate the oversmoothing problem and obtain the characteristics of the same nodes of drugs or diseases in the homogeneous network. Then, an automatic feature extraction method in the heterogeneous network is designed to obtain the features of drugs or diseases at different nodes. Finally, the obtained features are put into the fully connected network for nonlinear transformation, and the potential drug-disease pairs are obtained by bilinear decoding. Experimental results demonstrate that the DAHNGC model exhibits good predictive performance for drug-disease associations.


Assuntos
Desenvolvimento de Medicamentos , Redes Neurais de Computação
10.
Psychol Res Behav Manag ; 16: 71-83, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643733

RESUMO

Purpose: Stress may relate to an increased risk of psychological and physical disorders. Thus, a brief and efficient measurement instrument for researchers to measure stress is essentially needed. Participants and Methods: To assess measurement properties of the validated Chinese version of the Perceived Stress Questionnaire-13 (PSQ-C-13), we conducted a two-wave longitudinal study from September to December, 2021 with a convenient sample of medical students. Results: A two-factor (constraint and imbalance) structure showed good fit indices (Comparative Fit Index [CFI] = 0.972, Tucker-Lewis Index [TLI] = 0.966, Root Mean Square Error of Approximation [RMSEA] = 0.062). Spearman correlations with the Chinese Perceived Stress Scale-10 illustrated that convergent validity of the PSQ-C-13 was relatively satisfactory (r = 0.678 [baseline], 0.753 [follow-up]). Measurement invariance was supported across subgroups (gender, age, home location, single-child status, monthly households' income, and part-time status) and time points. Internal consistency was sound (Cronbach's α = 0.908 [baseline], 0.922 [follow-up]; McDonald's ω = 0.909 [baseline], 0.923 [follow-up]). Stability between time points was good (Intraclass Correlation Coefficient = 0.834). Conclusion: The two factors of the PSQ-C-13 including constraint and imbalance may adequately measure the level of stress on participants. The PSQ-C-13 is a convenient and efficient instrument that contains valid and reliable psychometric properties.

11.
BMC Psychol ; 11(1): 345, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853499

RESUMO

BACKGROUND: The 10-item Rosenberg Self-Esteem Scale (RSES) is a widely used tool for individuals to self-report their self-esteem; however, the factorial structures of translated versions of the RSES vary across different languages. This study aimed to validate the Chinese version of the RSES in the Chinese mainland using a longitudinal design. METHODS: A group of healthcare university students completed the RSES across three waves: baseline, 1-week follow-up, and 15-week follow-up. A total of 481 valid responses were collected through the three-wave data collection process. Exploratory factor analysis (EFA) was performed on the baseline data to explore the potential factorial structure, while confirmatory factor analysis (CFA) was performed on the follow-up data to determine the best-fit model. Additionally, the cross-sectional and longitudinal measurement invariances were tested to assess the measurement properties of the RSES for different groups, such as gender and age, as well as across different time points. Convergent validity was assessed against the Self-Rated Health Questionnaire (SRHQ) using Spearman's correlation. Internal consistency was examined using Cronbach's alpha and McDonald's omega coefficients, while test-retest reliability was assessed using intraclass correlation coefficient. RESULTS: The results of EFA revealed that Items 5, 8, and 9 had inadequate or cross-factor loadings, leading to their removal from further analysis. Analysis of the remaining seven items using EFA suggested a two-factor solution. A comparison of several potential models for the 10-item and 7-item RSES using CFA showed a preference for the 7-item form (RSES-7) with two factors. Furthermore, the RSES-7 exhibited strict invariance across different groups and time points, indicating its stability and consistency. The RSES-7 also demonstrated adequate convergent validity, internal consistency, and test-retest reliability, which further supported its robustness as a measure of self-esteem. CONCLUSIONS: The findings suggest that the RSES-7 is a psychometrically sound and brief self-report scale for measuring self-esteem in the Chinese context. More studies are warranted to further verify its usability.


Assuntos
Idioma , Humanos , Estudos Longitudinais , Reprodutibilidade dos Testes , Estudos Transversais , Psicometria/métodos , Inquéritos e Questionários
12.
Ann Intensive Care ; 13(1): 47, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37278862

RESUMO

PURPOSE: Stenotrophomonas maltophilia is a Gram-negative pathogen that most commonly causes hospital-acquired infections that can be extremely challenging to treat, contributing to underrecognized mortality throughout the world. The relative benefits of monotherapy as compared to combination therapy in patients diagnosed with S. maltophilia pneumonia, however, have yet to be established. METHODS: Data from 307 patients diagnosed with S. maltophilia hospital-acquired pneumonia (HAP) across four Chinese teaching hospitals from 2016 to 2022 were retrospectively analyzed. RESULTS: Of the analyzed patients, 55.7% (171/307) were administered combination definitive therapy, with a 30-day all-cause mortality rate of 41.0% (126/307). A propensity score weighting analysis revealed that compared with monotherapy, combination definitive therapy was associated with a comparable 30-day mortality risk in the overall patient cohort (OR 1.124, 95% CI 0.707-1.786, P = 0.622), immunocompetent patients (OR 1.349, 95% CI 0.712-2.554, P = 0.359), and patients with APACHE II scores < 15 (OR 2.357, 95% CI 0.820-6.677, P = 0.111), whereas it was associated with a decreased risk of death in immunocompromised patients (OR 0.404, 95% CI .170-0.962, P = 0.041) and individuals with APACHE II scores ≥ 15 (OR 0.494, 95% CI 0.256-0.951, P = 0.035). CONCLUSION: The present data suggest that when treating S. maltophilia-HAP, immunocompromised patients and individuals with APACHE II scores ≥ 15 may potentially benefit from combination therapy.

13.
Behav Sci (Basel) ; 13(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36829311

RESUMO

OBJECTIVES: This study aimed to investigate factors associated with sleep quality in healthcare students and to determine whether depressive and anxiety symptoms may explain some of the associations between sleep quality and self-rated health. STUDY DESIGN: This is a cross-sectional study at wave one. METHODS: A total of 637 healthcare students were recruited via a stratified random sampling method in Hangzhou, China. The Sleep Quality Questionnaire (SQQ) and the four-item Patient Health Questionnaire (PHQ-4) were used to assess sleep quality and depressive and anxiety symptoms, respectively. Self-rated health was assessed via a self-developed questionnaire of both physical and psychological health. Structural equation modeling was used to examine the direct and indirect effects of sleep quality on self-rated health through depressive and anxiety symptoms. RESULTS: Students engaged in part-time employment (p = 0.022), with poor perceived employment prospects (p = 0.009), and who did not participate in recreational sports (p = 0.008) had worse sleep quality. Structural equation modeling revealed a significant total effect of sleep quality on self-rated health (b = 0.592, p < 0.001), a significant direct effect of both sleep quality and depressive and anxiety symptoms on self-rated health (b = 0.277, 95% CI: 0.032-0.522), and a significant indirect effect of sleep quality on self-rated health through depressive and anxiety symptoms (b = 0.315, 95% CI: 0.174-0.457). CONCLUSIONS: Depressive and anxiety symptoms partially explain the association between sleep quality and self-rated health. Intervening upon sleep quality, depressive, and anxiety symptoms may bolster the self-rated health of healthcare students.

14.
Front Public Health ; 11: 1281571, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38213643

RESUMO

Objective: Sleep issues, negative emotions, and health conditions are commonly co-occurring, whereas their associations among healthcare students have yet to be elucidated. This study aimed to examine whether anxiety and depression mediate the relationship between sleep quality and subjective well-being in healthcare students. Methods: A cross-sectional survey was conducted among Chinese healthcare students (N = 348). A battery of paper-and-pencil questionnaires-the Sleep Quality Questionnaire (SQQ), World Health Organization-Five Well-Being Index (WHO-5), and Patient Health Questionnaire-4 (PHQ-4) were applied. Descriptive analysis with means (standard deviations) and counts (proportions), Spearman correlation analysis between the SQQ, WHO-5, and PHQ-4, and mediation analysis via structural equation models were performed. Results: Correlation analysis revealed statistically significant associations between sleep quality, anxiety and depression, and well-being among healthcare students. Mediation analysis identified that poor sleep quality produced relatively low levels of self-reported well-being, which were entirely attributable to anxiety and depression. Conclusion: Sleep quality was associated with subjective well-being, and this interrelationship was fully mediated by anxiety and depression. Interventions aimed at promoting sleep quality of healthcare students may contribute to promoting their well-being by reducing anxiety and depression.


Assuntos
Depressão , Qualidade do Sono , Humanos , Depressão/epidemiologia , Depressão/psicologia , Estudos Transversais , Ansiedade/psicologia , Estudantes/psicologia
15.
Sci Total Environ ; 839: 156075, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598663

RESUMO

In this work, a Mn2O3/Mn3O4-Cu1.5Mn1.5O4 spinel was fabricated and utilised as a catalyst to activate peroxydisulfate (PDS) leading to degradation of bisphenol A (BPA). The results showed that the system exhibited an excellent turnover frequency (TOF) of 2.7 × 10-3 s-1 and high stability. The amount of ion leaching was small and the degree of mineralisation was up to 66.2%. Superoxide radicals (O2-) were determined to be the dominant active species in the system. ≡Mn(II) and oxygen vacancies (Vo) were found to be the main active sites at the catalyst surface. The activation of PDS by the spinel catalyst and the reduction of dissolved oxygen both contributed to the production of O2- species. The synergistic effect of ≡Cu(I)/≡Cu(II) and ≡Mn(II)/≡Mn(III) redox pairs enabled the reaction to occur continuously. These results suggest the promise of this novel spinel catalyst in the removal of refractory organic compounds due to its excellent performance and stability. The catalyst may thus have great utility for environmental remediation.


Assuntos
Compostos Benzidrílicos , Superóxidos , Óxido de Alumínio , Compostos Benzidrílicos/química , Óxido de Magnésio , Oxigênio , Fenóis
16.
ACS Appl Mater Interfaces ; 13(32): 38553-38560, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34342965

RESUMO

Multiple-stage interband cascade infrared photodetector (ICIP) is a new class of semiconductor infrared photodetector that exhibits improved device performance in terms of responsivity and detectivity. The design of the device structure and the electronic structure on superlattices and quantum wells assume abrupt interfaces. However, the emergence of possible interface segregation and atom exchange can only be determined experimentally, impacting the device performance. In this work, the interface atom intermixing and their effects on the energy band structure in a molecular beam epitaxy grown ICIP are studied. Scanning transmission electron microscopy (STEM) reveals atom diffusion and intermixing between the constituent layers of the cascade structure, causing a shift in the quantum state energy levels of the layers and the consequent misalignment of the cascade structures. Combining the STEM observation with high-resolution X-ray diffraction, the alloy composition profiles of the layers are determined. Using the "real" graded composition profiles, the effective band gap of the superlattice absorber and the energy levels of the relaxation region and the tunneling region are recalculated showing a cutoff wavelength of the superlattice absorber 4.93 µm, which is 0.78 µm smaller than that calculated using the nominal step composition profile. However, its agreement is greatly improved with the measured cutoff wavelength of 5.03 µm. The energy level of the narrowest quantum well in the relaxation region is 0.091 eV higher than the conduction miniband of the absorber, which is also consistent with the experiments that the pho-response exits a "turn on" voltage of 0.1 V. The results reported here will help optimize the energy structure design of future ICIP with improved device performance.

17.
Eur J Haematol ; 81(1): 8-17, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18331597

RESUMO

Hyperfibrinolysis is a consequence of imbalance between fibrinolytic activators and their inhibitors. Increased levels of circulating plasminogen (Plg) activators such as tissue- or urokinase-type plasminogen activators (tPA or uPA respectively) are the most common causes of hyperfibrinolysis, occasionally causing major hemorrhages. We found that staphylokinase (SAK), a well-known Plg activator of bacterial origin, inhibits Plg activation mediated by endogenous tPA and uPA. Furthermore, mixture of SAK with tPA led to a significantly reduced Plg-dependent fibrinolysis. This inhibitory effect was exerted through direct action of SAK on Plg rather than indirectly on tPA or uPA. Inhibition of Plg activation by SAK is readily abrogated by interaction of SAK with human neutrophil peptides (HNPs). Finally, we show that NH2-terminal residues of SAK are important for the inhibitory effect of SAK on tPA- and uPA-mediated Plg activation. In conclusion, SAK reduces tPA/uPA-mediated Plg activation by means of SAK.Plg complex formation, consequently downregulating tPA/uPA-induced fibrinolysis.


Assuntos
Fibrinolisina/antagonistas & inibidores , Metaloendopeptidases/farmacologia , Ativadores de Plasminogênio/metabolismo , Adulto , Feminino , Fibrinolisina/biossíntese , Fibrinólise/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Plasminogênio/antagonistas & inibidores , Proteínas Recombinantes , Ativador de Plasminogênio Tecidual , Ativador de Plasminogênio Tipo Uroquinase
18.
Transl Psychiatry ; 8(1): 256, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30487579

RESUMO

The IPSAQ is a self-administered instrument designed to evaluate individuals' attributional style (AS). The purpose of this study is to examine the psychometric properties of the Chinese version of the Internal, Personal and Situational Attributions Questionnaire (C-IPSAQ). We also investigate if patients with depression and patients with delusions exhibit attributional biases. The English version of IPSAQ was translated into Chinese and back-translated into English for use in this study. 200 normal control individuals, 47 depressed patients, and 41 delusional patients diagnosed with schizophrenia were recruited for this study. Psychometric properties of this questionnaire were evaluated. The IPSAQ was found to have good internal consistency as a scale. The mean Cronbach's alpha of the six subscales was 0.697. The inter-rater reliability was also acceptable. The concurrent validity analysis revealed that the C-IPSAQ was significantly correlated with ASQ. The group-comparison analyses showed differences in attributional style between patients with depression and patients with delusions compared to normal controls. We confirmed the reliability and validity of the C-IPSAQ, and that the instrument can discriminate specific attributional biases between different patient populations. The C-IPSAQ is a valid instrument to assess attributional style in delusional and depressed patients.


Assuntos
Transtorno Depressivo/fisiopatologia , Escalas de Graduação Psiquiátrica/normas , Psicometria/normas , Esquizofrenia Paranoide/fisiopatologia , Autoimagem , Percepção Social , Pensamento/fisiologia , Adolescente , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/instrumentação , Reprodutibilidade dos Testes , Adulto Jovem
19.
Zhonghua Yi Xue Za Zhi ; 87(14): 971-4, 2007 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-17650422

RESUMO

OBJECTIVE: To investigate the roles the different functional activation areas in whole human brain related to movement play during motor preparation (CUE) and execution (GO). METHODS: Event-related functional MRI technique was used on 12 right-handed healthy subjects to record the brain activation in a manner of delayed sequential finger movement. Activation maps and time-signal intensity curves were generated. RESULTS: Bilateral anterior parts of supplementary motor area (Pre-SMA), bilateral posterior parietal cortex (PPC), and bilateral anterior premotor cortex (PMC) were strongly activated during the preparation period, while bilateral SMA proper, and contralateral primary motor cortex (M1) were strongly activated during the execution period, Cerebellar cortex was activated during both periods. The time-signal intensity curves based on single voxel indicated that above-mentioned brain areas were activated during both periods to different degrees; however, the characteristics of distribution in every area were different. CONCLUSION: The brain areas related to movement are activated differently during preparation period and execution period, areas close to M1 participate in the motor execution process mainly, and the areas away from M1 are concerned with motor preparation process chiefly.


Assuntos
Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Córtex Motor/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Mapeamento Encefálico , Córtex Cerebelar/fisiologia , Feminino , Lateralidade Funcional , Humanos , Masculino
20.
Mol Cancer ; 5: 62, 2006 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-17107625

RESUMO

BACKGROUND: The involvement of the cyclooxygenases (COX), in particular COX-2, is well documented for many tumours, e.g. colon, breast and prostate cancer, by both experimental and clinical studies. There are epidemiological data from subjects using NSAIDs, and experimental evidence supporting the hypothesis of prostaglandins (PGs) as regulators of tumourigenesis in the ovary. One of the end products of PG-synthesis, PGE2, regulates several key-processes, which are characteristic for tumour growth, e.g. angiogenesis, proliferation and apoptosisis. The present study investigated the pathway for PGE2-synthesis and signalling in ovarian tumourigenesis by analysing specimen from normal ovaries (n = 18), benign (B) (n = 8), borderline type (BL) (n = 6) and malignant tumours (AC) (n = 22). The expression and cell-specific localization of COX-1, COX-2, microsomal prostaglandin E synthase-1 (mPGES-1) and two of the receptors for PGE2, EP1 and EP2, were examined by immunoblotting (IB) and immunohistochemistry (IHC). RESULTS: The results are in line with earlier studies demonstrating an increase of COX-2 in AC compared to the normal ovary, B and BL tumours. Increased expressions were also observed for COX-1, mPGES-1 and EP-1 which all were significantly (p < 0.05) augmented in less differentiated AC (grades: moderately-, poorly- and undifferentiated). The increase of COX-2 was also correlated to stage (FIGO classification) with significant elevations in stages II and III. EP1 was increased in stage III while no significant alterations were demonstrated for COX-1, mPGES-1 or EP2 for stage. IHC revealed staining of the tumour cells, but also increase of COX-1, COX-2, mPGES-1 and EP1-2 in the stromal compartment of AC (grades: moderately-, poorly- and undifferentiated). This observation suggests interactions between tumour cells and stromal cells (fibroblasts, immune cells), e.g. paracrine signalling mediated by growth factors, cytokines and possibly PGs. CONCLUSION: The increases of COX-1, COX-2, mPGES-1 and EP1-2 in epithelial ovarian cancer, supports the hypothesis that PGE2-synthesis and signalling are of importance for malignant transformation and progression. The observed augmentations of COX-1, COX-2 and mPGES-1 have implications for future therapeutic strategies.


Assuntos
Dinoprostona/biossíntese , Neoplasias Ovarianas/metabolismo , Transdução de Sinais/fisiologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Densitometria , Dinoprostona/fisiologia , Progressão da Doença , Células Epiteliais/patologia , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Oxirredutases Intramoleculares/metabolismo , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Ovário/metabolismo , Prostaglandina-E Sintases , Receptores de Prostaglandina E/metabolismo
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