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2.
Gen Hosp Psychiatry ; 83: 93-100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37156219

RESUMO

OBJECTIVE: Our primary objective was to determine whether pre-existing vulnerabilities and resilience factors combined with objective hardship resulted in cumulative (i.e., additive) effects on psychological distress in pregnant individuals during the COVID-19 pandemic. A secondary objective was to determine whether any of the effects of pandemic-related hardship were compounded (i.e., multiplicative) by pre-existing vulnerabilities. METHOD: Data are from a prospective pregnancy cohort study, the Pregnancy During the COVID-19 Pandemic study (PdP). This cross-sectional report is based upon the initial survey collected at recruitment between April 5, 2020 and April 30, 2021. Logistic regressions were used to evaluate our objectives. RESULTS: Pandemic-related hardship substantially increased the odds of scoring above the clinical cut-off on measures of anxiety and depression symptoms. Pre-existing vulnerabilities had cumulative (i.e., additive) effects on the odds of scoring above the clinical cut-off on measures of anxiety and depression symptoms. There was no evidence of compounding (i.e., multiplicative) effects. Social support had a protective effect on anxiety and depression symptoms, but government financial aid did not. CONCLUSION: Pre-pandemic vulnerability and pandemic-related hardship had cumulative effects on psychological distress during the COVID-19 pandemic. Adequate and equitable responses to pandemics and disasters may require more intensive supports for those with multiple vulnerabilities.


Assuntos
COVID-19 , Angústia Psicológica , Feminino , Gravidez , Humanos , COVID-19/epidemiologia , Pandemias , SARS-CoV-2 , Depressão/diagnóstico , Estudos Transversais , Estudos de Coortes , Estudos Prospectivos , Ansiedade/psicologia , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
3.
Hong Kong Med J ; 29(2): 112-120, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37088699

RESUMO

INTRODUCTION: The use of artificial intelligence (AI) to identify acute intracranial haemorrhage (ICH) on computed tomography (CT) scans may facilitate initial imaging interpretation in the accident and emergency department. However, AI model construction requires a large amount of annotated data for training, and validation with real-world data has been limited. We developed an algorithm using an open-access dataset of CT slices, then assessed its utility in clinical practice by validating its performance on CT scans from our institution. METHODS: Using a publicly available international dataset of >750 000 expert-labelled CT slices, we developed an AI model which determines ICH probability for each CT scan and nominates five potential ICH-positive CT slices for review. We validated the model using retrospective data from 1372 non-contrast head CT scans (84 [6.1%] with ICH) collected at our institution. RESULTS: The model achieved an area under the curve of 0.842 (95% confidence interval=0.791-0.894; P<0.001) for scan-based detection of ICH. A pre-specified probability threshold of ≥50% for the presence of ICH yielded 78.6% accuracy, 73% sensitivity, 79% specificity, 18.6% positive predictive value, and 97.8% negative predictive value. There were 62 true-positive scans and 22 false-negative scans, which could be reduced to six false-negative scans by manual review of model-nominated CT slices. CONCLUSION: Our model exhibited good accuracy in the CT scan-based detection of ICH, considering the low prevalence of ICH in Hong Kong. Model refinement to allow direct localisation of ICH will facilitate the use of AI solutions in clinical practice.


Assuntos
Inteligência Artificial , Tomografia Computadorizada por Raios X , Humanos , Hong Kong , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Hemorragias Intracranianas/diagnóstico por imagem
4.
Eur J Paediatr Dent ; 23(3): 230-242, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36172904

RESUMO

AIM: To synthesise knowledge on the relative efficacies of non-pharmacological strategies for managing dental fear and anxiety (DFA) in children and adolescents, specifically their effects on behaviour, anxiety levels and pain perception. METHODS: An umbrella review on non-pharmacological strategies used to manage DFA in children and adolescents was conducted based the Joanna Briggs Institute methodology. Searches were performed in 5 main electronic databases and the grey-literature. Two independent reviewers selected and appraised the included studies using the AMSTAR2 tool. Disagreements were resolved by a third reviewer. CONCLUSION: Audio-visual distraction was effective in reducing anxiety during a variety of dental procedures including those requiring local anaesthesia. A combination of techniques may be more effective in managing DFA in children and adolescents, possibly improving pain perception and cooperative behaviour.


Assuntos
Ansiedade ao Tratamento Odontológico , Adolescente , Criança , Ansiedade ao Tratamento Odontológico/prevenção & controle , Humanos
5.
Zhonghua Yi Xue Za Zhi ; 102(25): 1887-1890, 2022 Jul 05.
Artigo em Chinês | MEDLINE | ID: mdl-35768385

RESUMO

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is mainly used for reversible acute respiratory failure that is difficult to correct with mechanical ventilation and other conventional measures or preparation of lung transplantation. Acute respiratory distress syndrome (ARDS) is a typical clinical syndrome of acute respiratory failure. The timing of starting VV-ECMO in severe ARDS still face many controversies and challenges. This paper we discuss the current feasible assessment methods of when to start VV-ECMO in ARDS, such as, optimization of mechanical ventilation parameters, monitoring of respiratory dynamics and hemodynamics, assessment of lung recruitability and electrical impedance tomography (EIT) real-time monitoring, etc.


Assuntos
Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Pulmão , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia
8.
Adv Funct Mater ; 31(6)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33708036

RESUMO

Itaconate (ITA) is an emerging powerhouse of innate immunity with therapeutic potential that is limited in its ability to be administered in a soluble form. We developed a library of polyester materials that incorporate ITA into polymer backbones resulting in materials with inherent immunoregulatory behavior. Harnessing hydrolytic degradation release from polyester backbones, ITA polymers resulted in the mechanism specific immunoregulatory properties on macrophage polarization in vitro. In a functional assay, the polymer-released ITA inhibited bacterial growth on acetate. Translation to an in vivo model of biomaterial associated inflammation, intraperitoneal injection of ITA polymers demonstrated a rapid resolution of inflammation in comparison to a control polymer silicone, demonstrating the value of sustained biomimetic presentation of ITA.

9.
Eur Arch Paediatr Dent ; 22(1): 83-92, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32418053

RESUMO

PURPOSE: To examine the relationship between parenting styles and parental attitudes towards oral health practices in children. METHODS: Parents of children aged 4-6 years presenting to four public dental clinics completed the Parenting Styles Dimensions Questionnaire (PSDQ) and a questionnaire on parental attitudes, child diet and oral hygiene practices. Child oral health was evaluated using Plaque Index (PI) and dmft-Index. RESULTS: Three hundred and eighty-nine children (mean age: 62.3 ± 9.8 months) were recruited. The median dmft was 4 (IQR = 9) and median PI was 1.5 (IQR = 0.8). An authoritative parenting style was observed in 95.1% of parents. Authoritative parents were more likely to monitor sweets/snacks intake (P = 0.004) and less inclined to offer sweets/snacks in exchange for good behaviour (P = 0.04) than permissive parents. However, actual between-meal snacking frequency did not differ between styles (P = 0.43). Permissive parents were less likely to ensure bedtime toothbrushing (P = 0.001) or brush thoroughly when busy or tired (P = 0.03) compared to authoritative parents; these attitudes were associated with higher frequencies of actual omission of bedtime toothbrushing (P = 0.006) in their children. A higher frequency of omitting bedtime toothbrushing significantly predicted a permissive parenting style (OR = 12.1, P = 0.009). Parenting styles were not associated with dmft (P = 0.72) and/or PI (P = 0.34). CONCLUSIONS: Authoritative parenting was associated with positive attitudes regarding both preventive dietary and oral hygiene practices. Actual oral hygiene practices were more ideal in children with authoritative parents, but parenting styles had no impact on actual dietary habits.


Assuntos
Saúde Bucal , Poder Familiar , Idoso , Criança , Pré-Escolar , Comportamentos Relacionados com a Saúde , Humanos , Pessoa de Meia-Idade , Relações Pais-Filho , Pais , Inquéritos e Questionários
10.
Sci Rep ; 10(1): 14736, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895429

RESUMO

Debate still exists for the management of choledocholithiasis. The purpose of this study is to quantify the rate of recurrent choledocholithiasis post choledochoscopic bile duct exploration (CBDE) in comparison to ERCP and sphincterotomy, and to demonstrate the feasibility of this approach in a busy metropolitan hospital. Data of patients undergoing CBDE from 2009-2014 at the Northern Hospital, Victoria, Australia, was collected retrospectively. Primary outcomes were bile duct clearance rate and rate of recurrent stones post-clearance. Secondary outcomes measured were post-operative complications, laparoscopic to open conversion rate and operative time. Data of patients undergoing ERCP at the same institution was collected and compared. In total, there were 4,091 cholecystectomy cases performed from 2009-2014, of which 260 (6.3%) of patients had an intraoperative cholangiography (IOC) indicating a common bile duct (CBD) stone. Two hundred and forty-eight patients (95.3%) had a CBDE. The remaining 12 patients (4.6%) had radiological clearance, which were excluded from the study. The overall clearance rate for patients undergoing CBDE was 84% (209/248). The risk of recurrent stones up to 8 years post clearance was 2% (4/209). In the same institution, and between 1998-2012, a total of 1,148 patients underwent ERCP, of which 571 had endoscopic sphincterotomy (ES). Forty-three patients required a repeat ERCP for recurrent CBD stones with a complication rate of 7.5%. Time to recurrence ranged from 6 months to 10 years with a mean of 4.5 years. The rate of recurrence was lower in the CBDE group compared to the patients who had an ERCP (8.9% vs. 2%). CBDE is a feasible and effective method for clearance of CBD stones at the time of laparoscopic cholecystectomy. This approach, although not widely used, reduces the need for ERCP, which has inherent complications. In the longer term, this series showed a significant reduction in the rate of CBD stone recurrence.


Assuntos
Colangiografia/métodos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Ducto Colédoco/cirurgia , Cálculos Biliares/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo/métodos , Colecistectomia Laparoscópica/métodos , Coledocolitíase/cirurgia , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Esfinterotomia Endoscópica/métodos , Adulto Jovem
12.
Eur Rev Med Pharmacol Sci ; 23(4): 1388-1396, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30840259

RESUMO

OBJECTIVE: The aim of this study was to investigate whether lnc00908 could affect the proliferative and migratory behaviors of ovarian cancer (OC) cells by regulating microRNA-495-5p, thus participating in the development of OC. PATIENTS AND METHODS: Quantitative Real Time-Polymerase Chain Reaction (QRT-PCR) was used to detect the expression levels of lnc00908 and microRNA-495-5p in OC tissues and normal ovarian tissues, as well as OC cell lines. The regulatory effects of lnc00908 and microRNA-495-5p on the proliferative and migration abilities of OC cells were detected by cell counting kit-8 (CCK-8) and transwell assay, respectively. The binding relationship between microRNA-495-5p and ANXA3, as well as miR-495-5p and lnc00908, was examined by luciferase reporter gene assay. Gain-of-function experiments were conducted to verify whether lnc00908 could affect the proliferative and migratory behaviors of OC cells by regulating microRNA-495-5p. RESULTS: Lnc00908 was highly expressed in OC tissues, and its expression was positively correlated with tumor stage. Overexpression of lnc00908 markedly promoted the proliferative and migratory abilities of SKOV3 and OVCAR cells. Luciferase reporter gene assay showed that lnc00908 could bind to microRNA-495-5p. However, microRNA-495-5p was significantly downregulated in OC tissues. Overexpression of microRNA-495-5p reversed the enhanced abilities of proliferation and migration in SKOV3 and OVCAR3 cells by lnc00908 overexpression. ANXA3 was a target gene of microRNA-495-5p. Moreover, overexpression of ANXA3 attenuated the inhibitory effect of miR-495-5p on the proliferative and migratory behaviors of SKOV3 and OVCAR3 cells. CONCLUSIONS: We found that the high expression of lnc00908 can promote the proliferation and migration abilities of OC cells through sponging microRNA-495-5p to regulate ANXA3 expression.


Assuntos
MicroRNAs/metabolismo , Neoplasias Ovarianas/patologia , RNA Longo não Codificante/metabolismo , Regiões 3' não Traduzidas , Anexina A3/química , Anexina A3/genética , Anexina A3/metabolismo , Área Sob a Curva , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/química , MicroRNAs/genética , Estadiamento de Neoplasias , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/mortalidade , Ovário/metabolismo , Ovário/patologia , RNA Longo não Codificante/genética , Curva ROC , Alinhamento de Sequência , Taxa de Sobrevida
13.
Mater Today Chem ; 14: 100207, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31903442

RESUMO

Hydrogen is considered as an ideal and sustainable energy carrier because of its high energy density and carbon-free combustion. Electrochemical water splitting is the only solution for uninterrupted, scalable, and sustainable production of hydrogen without carbon emission. However, a large-scale hydrogen production through electrochemical water splitting depends on the availability of earth-abundant electrocatalysts and a suitable electrolyte medium. In this article, we demonstrate that hydrogen evolution reaction (HER) performance of electrocatalytic materials can be controlled by their surface functionalization and selection of a suitable electrolyte solution. Here, we report syntheses of few-layered MoS2 nanosheets, NiO nanoparticles (NPs), and multiwalled carbon nanotubes (MWCNTs) using scalable production methods from earth-abundant materials. Magnetic measurements of as-produced electrocatalyst materials demonstrate that MoS2 nanoflakes are diamagnetic, whereas surface-functionalized MoS2 and its composite with carbon nanotubes have strong ferromagnetism. The HER performance of the few-layered pristine MoS2 nanoflakes, MoS2/NiO NPs, and MoS2/NiO NPs/MWCNT nanocomposite electrocatalysts are studied in acidic and alkaline media. For bare MoS2, the values of overpotential (η10) in alkaline and acidic media are 0.45 and 0.54 V, respectively. Similarly, the values of current density at 0.5 V overpotential are 27 and 6.2 mA/cm2 in alkaline and acidic media, respectively. The surface functionalization acts adversely in the both alkaline and acidic media. MoS2 nanosheets functionalized with NiO NPs also demonstrated excellent performance for oxygen evolution reaction with anodic current of ~60 mA/cm2 and Tafel slope of 78 mVdec-1 in alkaline medium.

14.
Zhonghua Yi Xue Za Zhi ; 98(31): 2476-2480, 2018 Aug 21.
Artigo em Chinês | MEDLINE | ID: mdl-30138998

RESUMO

Objective: To explore whether cephalic artery peak velocity variation during passive leg raising (ΔVpeak(CA)-PLR) could effectively predict fluid responsiveness in mechanically ventilated severe sepsis patients with spontaneous breathing. Methods: Total of 38 patients on mechanical ventilation with spontaneous breathing admitted to the Fourth Departments of Intensive Care Unit (ICU) of Fujian Provincial Hospital from January to December in 2017 were enrolled.The patients were diagnosed with severe sepsis or sepsis shock.The peak velocity in cephalic artery (Vpeak(CA)) during PLR was measured by bedside portable ultrasonic, and then ΔVpeak(CA)-PLR was calculated.All patients received volume expansion (VE) test and the changes of stroke volume during VE test (ΔSV-VE) were measured.Patients were classified as responsive group or non-responsive group according to the ΔSV-VE increased ≥15% or not after VE test.Furthermore, the sensitivity and specificity of ΔVpeak(CA)-PLR for predicting fluid responsiveness were evaluated by receiver operating characteristic (ROC) curve.The comparisons between groups were performed with Student's unpaired two-tailed t test, and Pearson's test was used for the correlation analysis. Results: Among the patients, 22 cases responded to VE test and the rest 16 cases did not.There were no significantly differences in age, gender, body mass index, infection site, sepsis-related organ failure assessment score, acute physiology and chronic health evaluation Ⅱ score, ventilator parameters and dose of vasoactive agent between the two groups.The ΔVpeak(CA)-PLR in responsive group was markedly higher than that in non-responsive group (15.7%±4.2% vs 6.9%±4.3%, t=6.240, P<0.05), and the ΔVpeak(CA)-PLR in the responsive group was positively related to the ΔSV-VE (r=0.723, P<0.05). Furthermore, the area of ΔVpeak(CA)-PLR under ROC curve was 0.912.The sensitivity and specificity of ΔVpeak(CA)-PLR≥12.2% to predict fluid responsiveness in the patients with sepsis were 81.8% and 87.5%, respectively. Conclusion: ΔVpeak(CA)-PLR measured by bedside portable ultrasonic can predict the fluid responsiveness in mechanically ventilated severe sepsis patients with spontaneous breathing, and it can be used to guide further fluid resuscitation.


Assuntos
Sepse , Artérias , Hidratação , Hemodinâmica , Humanos , Unidades de Terapia Intensiva , Curva ROC , Respiração Artificial , Volume Sistólico
15.
Biomater Sci ; 5(7): 1241-1245, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28589998

RESUMO

Using a novel magnetic field bioreactor, this work evaluated the chondrogenesis of scaffold-free human mesenchymal stem cell sheets in response to static and variable magnetic fields, as well as mechanical stimulation via 4.4 µm magnetic particles. Neither static nor variable magnetic fields generated by 1.44-1.45 T permanent magnets affected cartilage formation. Notably, magnetic field-induced mechanical stimulation by magnetic particles, which applied forces to the cells and ECM statically (4.39 pN) or cyclically (1.06-63.6 pN; 16.7 mHz), also did not affect cartilage formation.


Assuntos
Condrogênese , Campos Magnéticos , Fenômenos Mecânicos , Células-Tronco Mesenquimais/citologia , Microesferas , Humanos
17.
Metallomics ; 9(4): 382-390, 2017 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-27909710

RESUMO

Optical epifluorescence microscopy was used in conjunction with X-ray fluorescence imaging to monitor the stability and intracellular distribution of the luminescent rhenium(i) complex fac-[Re(CO)3(phen)L], where phen = 1,10-phenathroline and L = 5-(4-iodophenyl)tetrazolato, in 22Rv1 cells. The rhenium complex showed no signs of ancillary ligand dissociation, a conclusion based on data obtained via X-ray fluorescence imaging aligning iodine and rhenium distributions. A diffuse reticular localisation was detected for the complex in the nuclear/perinuclear region of cells, by either optical or X-ray fluorescence imaging techniques. X-ray fluorescence also showed that the rhenium complex disrupted the homeostasis of some biologically relevant elements, such as chlorine, potassium and zinc.


Assuntos
Complexos de Coordenação/análise , Substâncias Luminescentes/análise , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Rênio/análise , Tetrazóis/análise , Linhagem Celular Tumoral , Humanos , Fenantrolinas/análise , Raios X
18.
Arch Osteoporos ; 11: 5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26754792

RESUMO

UNLABELLED: The trabecular bone score (TBS) was obtained from the gray levels of a dual X-ray absorptiometry (DXA) image to evaluate bone microarchitecture. Here, we established the reference plots of TBS in healthy Chinese women of Nanjing area. The TBS references are similar with French and US Caucasian women but higher than Japanese women. PURPOSE: The aim of the study was to establish the reference plots of the TBS in healthy Chinese women of the Nanjing area. METHODS: A total of 537 healthy Chinese women of the Nanjing area were recruited, and the study was approved by the Ethics Committee of the First Affiliated Hospital with Nanjing Medical University. The TBS of the lumbar spine and the bone mineral density (BMD) of the lumbar spine and femur were measured using dual X-ray absorptiometry. The mean ± standard deviation (SD) of the TBS in women with different age groups was calculated. The correlation of TBS and age and BMD was calculated using regression analysis. RESULTS: The reference plots of the TBS were established in healthy Chinese women of the Nanjing area between the ages of 20 and 89 years. The average TBS for total subjects was 1.32 ± 0.11 and reached the peak at the age of 20-29 years and then decreased with age thereafter. The determinant coefficient between TBS and age was 0.5065 while between TBS and BMD was 0.5191. After adjusting for lumbar total BMD, the TBS significantly correlated with age in whole subjects and only in the subgroup of ages 50-59 years. CONCLUSIONS: This study suggested that TBS decreased with age and correlated positively with BMD. The TBS reference of Chinese women is similar with those of French and US Caucasian women but higher than that of Japanese women. Furthermore, the TBS may be more significantly applied in women in menopause for less than 10 years.


Assuntos
Densidade Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Absorciometria de Fóton/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/etnologia , Osso e Ossos/diagnóstico por imagem , China/etnologia , Feminino , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Valores de Referência , Análise de Regressão , Adulto Jovem
19.
Clin Transl Oncol ; 18(1): 65-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26250764

RESUMO

OBJECTIVE: The aim of the this study was to analyze the status of sex-determining region Y-related high-mobility group box 4 (SOX4) expression in varied human cancers and its correlation with overall survival in patients with human cancers. METHODS: To observe initially the expression status of SOX4 in twenty kinds of human cancers at protein database (The Human Protein Atlas). We systematically and carefully searched the studies from electronic databases and seriously identified according to eligibility criteria. The correlation between SOX4 expression and overall survival in human cancers was evaluated through Review Manager. RESULTS: We found that SOX4 expression was significantly positive in most types of human cancer tissues, and the positive rate of SOX4 expression was about 78 % in overall cancer tissues. Furthermore, a total of 10 studies which included 1348 cancer patients were included in the final analysis. Meta-analysis showed that SOX4 overexpression was correlated with a poor overall survival and the pooled hazard ratio (HR), and corresponding 95 % confidence interval (CI) was 1.67 (95 % CI 1.01-2.78). From subgroup analyses, we present evidence that SOX4 overexpression was an unfavorable prognostic factor for colorectal cancer patients' recurrence-free survival and gastric cancer patients' overall survival, and the pooled HRs (95 % CI) were 1.73 (95 % CI 1.04-2.88) and 3.74 (95 % CI 1.04-13.45), respectively. CONCLUSIONS: In summary, SOX4 is a potential prognostic biomarker in human cancers.


Assuntos
Biomarcadores Tumorais , Neoplasias/diagnóstico , Fatores de Transcrição SOXC/fisiologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Imuno-Histoquímica , Análise em Microsséries , Neoplasias/genética , Neoplasias/metabolismo , Prognóstico , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo , Análise Serial de Tecidos
20.
Rev Sci Instrum ; 86(11): 113705, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26628142

RESUMO

In situ characterization of micro- and nanoscale defects in polycrystalline thin-film materials is required to elucidate the physics governing defect formation and evolution during photovoltaic device fabrication and operation. X-ray fluorescence spectromicroscopy is particularly well-suited to study defects in compound semiconductors, as it has a large information depth appropriate to study thick and complex materials, is sensitive to trace amounts of atomic species, and provides quantitative elemental information, non-destructively. Current in situ methods using this technique typically require extensive sample preparation. In this work, we design and build an in situ temperature stage to study defect kinetics in thin-film solar cells under actual processing conditions, requiring minimal sample preparation. Careful selection of construction materials also enables controlled non-oxidizing atmospheres inside the sample chamber such as H2Se and H2S. Temperature ramp rates of up to 300 °C/min are achieved, with a maximum sample temperature of 600 °C. As a case study, we use the stage for synchrotron X-ray fluorescence spectromicroscopy of CuIn(x)Ga(1-x)Se2 (CIGS) thin-films and demonstrate predictable sample thermal drift for temperatures 25-400 °C, allowing features on the order of the resolution of the measurement technique (125 nm) to be tracked while heating. The stage enables previously unattainable in situ studies of nanoscale defect kinetics under industrially relevant processing conditions, allowing a deeper understanding of the relationship between material processing parameters, materials properties, and device performance.

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