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1.
Nat Commun ; 14(1): 1038, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914643

RESUMO

Recently, there has been substantial effort to understand the fundamental characteristics of warm ocean temperature extremes-known as marine heatwaves (MHWs). However, MHW research has primarily focused on the surface signature of these events. While surface MHWs (SMHW) can have dramatic impacts on marine ecosystems, extreme warming along the seafloor can also have significant biological outcomes. In this study, we use a high-resolution (~8 km) ocean reanalysis to broadly assess bottom marine heatwaves (BMHW) along the continental shelves of North America. We find that BMHW intensity and duration varies strongly with bottom depth, with typical intensities ranging from ~0.5 °C-3 °C. Further, BMHWs can be more intense and persist longer than SMHWs. While BMHWs and SMHWs often co-occur, BMHWs can also exist without a SMHW. Deeper regions in which the mixed layer does not typically reach the seafloor exhibit less synchronicity between BMHWs and SMHWs.

2.
Nat Commun ; 13(1): 7849, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543763

RESUMO

Bandgap gradient is a proven approach for improving the open-circuit voltages (VOCs) in Cu(In,Ga)Se2 and Cu(Zn,Sn)Se2 thin-film solar cells, but has not been realized in Cd(Se,Te) thin-film solar cells, a leading thin-film solar cell technology in the photovoltaic market. Here, we demonstrate the realization of a bandgap gradient in Cd(Se,Te) thin-film solar cells by introducing a Cd(O,S,Se,Te) region with the same crystal structure of the absorber near the front junction. The formation of such a region is enabled by incorporating oxygenated CdS and CdSe layers. We show that the introduction of the bandgap gradient reduces the hole density in the front junction region and introduces a small spike in the band alignment between this and the absorber regions, effectively suppressing the nonradiative recombination therein and leading to improved VOCs in Cd(Se,Te) solar cells using commercial SnO2 buffers. A champion device achieves an efficiency of 20.03% with a VOC of 0.863 V.

3.
Therap Adv Gastroenterol ; 15: 17562848221133581, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353735

RESUMO

Background: Pancreatic cystic fluid (PCF) analysis is frequently used for cyst diagnosis with carcinoembryonic antigen (CEA) being the most accepted biomarker. Low glucose levels in PCF were previously suggested as a marker for mucinous cysts. A bed-side glucometer is a point-of care, immediate, simple, and cheap method which requires a small volume of PCF. Objectives: The aim of our study was to identify the optimal glucose cut-off level for identifying mucinous cysts, evaluate the diagnostic accuracy of glucose compared to CEA, and validate glucometry against reference laboratory biochemical analysis. Design: A single-center prospective cohort study. Methods: Consecutive patients aged 18 and older, who underwent pancreatic cyst evaluation, at the Tel Aviv Medical Center between 2016 and 2021 were analyzed. Cyst type was defined based on clinical, laboratory, and radiologic findings. Glucose was measured using laboratory biochemical analysis and two glucometers. Receiver operating characteristic analysis derived sensitivity, specificity, and accuracy were calculated and McNemar test was used to compare between methods. Results: One hundred and one PCF samples were evaluated. The areas under the receiver operating characteristics curve for identifying mucinous cysts using glucometer, glucose laboratory, and their combination were 0.88 (p < 0.001), 0.92 (p < 0.001), and 0.93 (p < 0.001), respectively. A glucose level of 87 mg/dL was identified as the optimal laboratory glucose threshold value to detect mucinous cyst with a sensitivity of 90.9%, specificity of 83.3%, and accuracy of 89.3, higher in comparison to cyst fluid CEA. Furthermore, PCF glucose levels had the strongest association with mucinous cysts. Conclusion: Our findings suggest that PCF glucose level is more accurate than CEA for the diagnosis of mucinous cysts. Glucometry glucose level assessment demonstrated an excellent correlation with laboratory glucose measurements and may become a useful diagnostic test.

4.
J Cardiovasc Pharmacol Ther ; 27: 10742484221121507, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36282079

RESUMO

INTRODUCTION: Cholesterol efflux capacity (CEC) is impaired following acute myocardial infarction (AMI). CSL112 is an intravenous preparation of human plasma-derived apoA-I formulated with phosphatidylcholine (PC). CSL112 is intended to improve CEC and thereby prevent early recurrent cardiovascular events following AMI. AEGIS-I (ApoA-I Event Reducing in Ischemic Syndromes I) was a multicenter, randomized, double-blind, placebo-controlled, dose-ranging phase 2b study, designed to evaluate the hepatic and renal safety of CSL112. Here, we report an analysis of a pharmacokinetic (PK) and pharmacodynamic (PD) substudy of AEGIS-I. METHODS: AMI patients were stratified by renal function and randomized 3:3:2 to 4, weekly, 2-hour infusions of low- and high-dose (2 g and 6 g) CSL112, or placebo. PK/PD assessments included plasma concentrations of apoA-I and PC, and measures of total and ABCA1-dependent CEC, as well as lipids/lipoproteins including high density lipoprotein cholesterol (HDL-C), non-HDL-C, low density lipoprotein cholesterol (LDL-C), ApoB, and triglycerides. Inflammatory and cardio-metabolic biomarkers were also evaluated. RESULTS: The substudy included 63 subjects from AEGIS-I. CSL112 infusions resulted in rapid, dose-dependent increases in baseline corrected apoA-I and PC, which peaked at the end of the infusion (Tmax ≈ 2 hours). Similarly, there was a dose-dependent elevation in both total CEC and ABCA1-mediated CEC. Mild renal impairment did not affect the PK or PD of CSL112. CSL112 administration was also associated with an increase in plasma levels of HDL-C but not non-HDL-C, LDL-C, apoB, or triglycerides. No dose-effects on inflammatory or cardio-metabolic biomarkers were observed. CONCLUSION: Among patients with AMI, impaired CEC was rapidly elevated by CSL112 infusions in a dose-dependent fashion, along with an increase in apoA-I plasma concentrations. Findings from the current sub-study of the AEGIS-I support a potential atheroprotective benefit of CSL112 for AMI patients.


Assuntos
Apolipoproteína A-I , Infarto do Miocárdio , Humanos , Apolipoproteína A-I/efeitos adversos , Apolipoproteínas B/uso terapêutico , Biomarcadores , Colesterol , HDL-Colesterol , LDL-Colesterol , Infarto do Miocárdio/tratamento farmacológico , Fosfatidilcolinas/uso terapêutico , Triglicerídeos
5.
Eur J Gastroenterol Hepatol ; 34(11): 1111-1115, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36170679

RESUMO

BACKGROUND: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) is a developing therapeutic approach for premalignant pancreatic-cystic neoplasms (PCNs) and small pancreatic neuroendocrine tumors (PNETs). The safety and efficacy of pancreatic EUS-RFA were previously reported in small series. Herein we report our initial experience with RFA of PCNs and small PNETs. METHODS: This is a prospective single-center study including 12 patients with a median follow-up of 7 months, with either PCN or PNET &lt;2 cm. Eligible PCNs were either intraductal papillary mucinous neoplasms (IPMN) with worrisome features or mucinous cystic neoplasms (MCN) that were not eligible or refused surgery. Ablation was performed using a 19-gauge dedicated needle. RESULTS: Twelve patients were treated, five had PCNs (four IPMNs, one MCN; median size of 36 mm, range 12-60) and seven had PNETs (median size 8.9 mm, range 6-18). Among patients with PCNs, the complete radiologic response was achieved in 3/5 (60%), partial response in 1/5 (20%) and failure in 1/5 (20%). Among six patients with nonfunctioning PNETs, the complete radiologic response was achieved in 4/6 (66.7%), partial radiologic response in 0/6 (0%) and failure in 2/6 (33.3%). Following a median follow-up of 7 months. One patient with insulinoma showed complete resolution of hypoglycemia-related symptoms. Three postprocedural adverse events occurred, including one case (1/12, 8.3%) of mild acute pancreatitis and two cases (2/12, 16.7%) of abdominal pain. CONCLUSION: EUS-guided RFA for premalignant PCNs and PNETs is feasible and well-tolerated. Efficacy would be further evaluated with continued follow-up of patients.


Assuntos
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendócrinos , Cisto Pancreático , Neoplasias Pancreáticas , Pancreatite , Ablação por Radiofrequência , Humanos , Doença Aguda , Endossonografia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/cirurgia , Cisto Pancreático/diagnóstico por imagem , Cisto Pancreático/cirurgia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
6.
BMJ Open ; 12(9): e057614, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123094

RESUMO

INTRODUCTION: Most patients admitted to hospital recover with treatments that can be administered on the general ward. A small but important group deteriorate however and require augmented organ support in areas with increased nursing to patient ratios. In observational studies evaluating this cohort, proxy outcomes such as unplanned intensive care unit admission, cardiac arrest and death are used. These outcome measures introduce subjectivity and variability, which in turn hinders the development and accuracy of the increasing numbers of electronic medical record (EMR) linked digital tools designed to predict clinical deterioration. Here, we describe a protocol for developing a new outcome measure using mixed methods to address these limitations. METHODS AND ANALYSIS: We will undertake firstly, a systematic literature review to identify existing generic, syndrome-specific and organ-specific definitions for clinically deteriorated, hospitalised adult patients. Secondly, an international modified Delphi study to generate a short list of candidate definitions. Thirdly, a nominal group technique (NGT) (using a trained facilitator) will take a diverse group of stakeholders through a structured process to generate a consensus definition. The NGT process will be informed by the data generated from the first two stages. The definition(s) for the deteriorated ward patient will be readily extractable from the EMR. ETHICS AND DISSEMINATION: This study has ethics approval (reference 16399) from the Central Adelaide Local Health Network Human Research Ethics Committee. Results generated from this study will be disseminated through publication and presentation at national and international scientific meetings.


Assuntos
Hospitalização , Hospitais , Adulto , Consenso , Humanos , Unidades de Terapia Intensiva , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
7.
Therap Adv Gastroenterol ; 15: 17562848221104306, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747617

RESUMO

Background: The association between intraductal papillary mucinous neoplasms (IPMNs) and colorectal cancer (CRC) and polyps is controversial. Objectives: To compare the prevalence of CRC and colorectal polyps among patients with IPMN and matched average risk individuals. Methods: A match cross-sectional historical study comparing colonoscopy findings of 310 patients with IPMN cysts who underwent at least one colonoscopy examination from 2004 through 2019, with 310 age- and gender-matched average risk participants who underwent a screening colonoscopy. CRC and polyps were assessed in both groups. The prevalence and odds ratio were calculated. Results: CRC was diagnosed in 16 of 310 patients with IPMN (5.2%), and at least one polyp was detected in 96 patients (31%). The prevalence of CRC was greater among patients with IPMN than in matched individuals [5.2% versus 1.3%, p = 0.012, prevalence odds ratio (POR) 4, confidence interval (CI) 1.29-16.44]. The overall prevalence of polyps was not higher among patients with IPMN than in matched individuals (31% versus 26.8%, p = 0.291, POR 1.22, CI 0.85-1.76). However, the prevalence of colorectal adenomas with high-grade dysplasia was higher in patients with IPMN than in matched individuals (4.2% versus 1%, p = 0.02, POR 4.33, CI, 1.19-23.7). The prevalence of large polyps (i.e. more than 20 mm in size) was also greater in patients with IPMN than in matched individuals (6.1% versus 1.9%, p = 0.011, POR 3.6, CI, 1.29-12.40). Conclusion: Patients with IPMN have a significantly higher prevalence of CRC and advanced polyps than the average risk population. In view of our findings, we suggest that once the diagnosis of IPMN is made, special consideration of CRC should be undertaken.

8.
ACS Appl Mater Interfaces ; 14(17): 19644-19651, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35451818

RESUMO

The performance of CdTe solar cells has advanced impressively in recent years with the incorporation of Se. Instabilities associated with light soaking and copper reorganization have been extensively examined for the previous generation of CdS/CdTe solar cells, but instabilities in Cu-doped Se-alloyed CdTe devices remain relatively unexplored. In this work, we fabricated a range of CdSe/CdTe solar cells by sputtering CdSe layers with thicknesses of 100, 120, 150, 180, and 200 nm on transparent oxide-coated glass and then depositing CdTe by close-spaced sublimation. After CdCl2 annealing, Cu-doping, and back metal deposition, a variety of analyses were performed both before and after light soaking to understand the changes in device performance. The device efficiency was degraded with light soaking in most cases, but devices fabricated with a CdSe layer thickness of 120 nm showed reasonably good efficiency initially (13.5%) and a dramatic improvement with light soaking (16.5%). The efficiency improvement is examined within the context of Cu ion reorganization that is well known for CdS/CdTe devices. Low-temperature photoluminescence data and Voc versus temperature measurements indicate a reduction in nonradiative recombination due to the passivation of defects and defect complexes in the graded CdSexTe1-x layer.

9.
J Gastrointest Surg ; 26(6): 1233-1240, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35355173

RESUMO

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is the first line treatment for choledocholithiasis. In many occasions, several attempts of ERCP are performed until failure is declared and surgical treatment is applied, in many times following procedure-related complications. We present the results of surgical management of patients with choledocholithiasis following repeated failures of ERCP due to impaction of multiple large stones. METHODS: Patients that underwent surgical treatment for choledocholithiasis following repeated ERCP attempts between January 2006 and December 2018 were retrospectively assessed. Post-ERCP complications were evaluated and the surgical approach, technique, and outcomes were assessed. RESULTS: One hundred and two patients were operated on for choledocholithiasis following repeated failed ERCP. All the patients had at least 2 failed attempts (mean = 3.2 ± 1.7), and 25 (23.5%) suffered major ERCP-related complications. Following choledochotomy and stone extraction, bilioenteric anastomosis was done in the vast majority of patients (90.2%), most commonly choledochoduodenostomy (62%). Thirty-eight (37%) patients had minimally invasive procedure (laparoscopic n = 26, robotic assisted n = 12). Major post-operative complications (Clavien-Dindo ≥ 3) occurred in 24 patients (23.5%). Nine patients (8.8%) were re-operated and 10 (9.8%) were readmitted within 30 days from surgery. Three patients died within 30 days from surgery. Older patients had significantly more ERCP attempts and suffered higher post-operative mortality. During a median follow-up of 70 months, the only biliary complication was an anastomotic stricture in one patient. CONCLUSION: Surgery for CBDS after failure of ERCP is safe and provides a highly effective long-term solution.


Assuntos
Coledocolitíase , Laparoscopia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Coledocolitíase/cirurgia , Coledocostomia/efeitos adversos , Humanos , Laparoscopia/métodos , Estudos Retrospectivos , Resultado do Tratamento
10.
Materials (Basel) ; 14(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34640041

RESUMO

Motivated by their utility in CdTe-based thin film photovoltaics (PV) devices, an investigation of thin films of the magnesium-zinc oxide (MgxZn1-xO or MZO) alloy system was undertaken applying spectroscopic ellipsometry (SE). Dominant wurtzite phase MZO thin films with Mg contents in the range 0 ≤ x ≤ 0.42 were deposited on room temperature soda lime glass (SLG) substrates by magnetron co-sputtering of MgO and ZnO targets followed by annealing. The complex dielectric functions ε of these films were determined and parameterized over the photon energy range from 0.73 to 6.5 eV using an analytical model consisting of two critical point (CP) oscillators. The CP parameters in this model are expressed as polynomial functions of the best fitting lowest CP energy or bandgap E0 = Eg, which in turn is a quadratic function of x. As functions of x, both the lowest energy CP broadening and the Urbach parameter show minima for x ~ 0.3, which corresponds to a bandgap of 3.65 eV. As a result, it is concluded that for this composition and bandgap, the MZO exhibits either a minimum concentration of defects in the bulk of the crystallites or a maximum in the grain size, an observation consistent with measured X-ray diffraction line broadenings. The parametric expression for ε developed here is expected to be useful in future mapping and through-the-glass SE analyses of partial and complete PV device structures incorporating MZO.

11.
ACS Appl Mater Interfaces ; 13(32): 38432-38440, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34347421

RESUMO

Copper (Cu) incorporation is a key process for fabricating efficient CdTe-based thin-film solar cells and has been used in CdTe-based solar cell module manufacturing. Here, we investigate the effects of different Cu precursors on the performance of CdTe-based thin-film solar cells by incorporating Cu using a metallic Cu source (evaporated Cu) and ionic Cu sources (solution-processed cuprous chloride (CuCl) and copper chloride (CuCl2)). We find that ionic Cu precursors offer much better control in Cu diffusion than the metallic Cu precursor, producing better front junction quality, lower back-barrier heights, and better bulk defect property. Finally, outperforming power conversion efficiencies of 17.2 and 17.5% are obtained for devices with cadmium sulfide and zinc magnesium oxide as the front window layers, respectively, which are among the highest reported CdTe solar cells efficiencies. Our results suggest that an ionic Cu precursor is preferred as the dopant to fabricate efficient CdTe thin-film solar cells and modules.

12.
Surg Laparosc Endosc Percutan Tech ; 31(5): 528-532, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-34080823

RESUMO

Negative endoscopic retrograde cholangiopancreatography (ERCP) for suspected common bile duct stones (CBDS) may be associated with significant morbidity and should be avoided. Between 2010 and 2018, 85 patients who have undergone negative ERCP for suspected CBDS were retrospectively evaluated and compared with 318 patients with positive findings. Predictors for negative ERCP were assessed. Patients with negative ERCP were younger; had increased levels of serum amylase, alanine transaminase, and lactate dehydrogenase; and increased hemoglobin. Even though preprocedure computed tomography (CT) or ultrasonography demonstrating CBDS were highly predictive of positive findings on ERCP, of the 212 patients with CBDS on computed tomography or ultrasonography, 17 (8%) eventually had a negative ERCP, suggesting spontaneous stone passage. An increased serum amylase level was the only predictor for negative ERCP in multivariate analysis, including in patients with preprocedure CBDS on imaging. The data suggest that assessing serum amylase may assist in avoiding unnecessary examinations.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Cálculos Biliares , Amilases , Ducto Colédoco , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/cirurgia , Humanos , Estudos Retrospectivos
13.
Am Heart J ; 231: 121-127, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065120

RESUMO

Acute myocardial infarction (MI) patients remain at high risk for recurrent events. Cholesterol efflux, mediated by apolipoprotein A-I, removes excess cholesterol from atherosclerotic plaque and transports it to the liver for excretion. Impaired cholesterol efflux is associated with higher cardiovascular (CV) event rates among both patients with stable coronary artery disease and recent MI. CSL112, a novel intravenous formulation of apolipoprotein A-I (human) derived from human plasma, increases cholesterol efflux capacity. AEGIS-II is a phase 3, multicenter, double-blind, randomized, placebo-controlled, parallel-group trial investigating the efficacy and safety of CSL112 compared to placebo among high-risk acute MI participants. Eligibility criteria include age ≥ 18 years with type 1 (spontaneous) MI, evidence of multivessel stable coronary artery disease, and presence of diabetes requiring pharmacotherapy, or ≥2 of the following: age ≥ 65 years, prior MI, or peripheral artery disease. A target sample of 17,400 participants will be randomized 1:1 to receive 4 weekly infusions of CSL112 6 g or placebo, initiated prior to or on the day of discharge and within 5 days of first medical contact. The primary outcome is the time to first occurrence of the composite of CV death, MI, or stroke through 90 days. Key secondary outcomes include the total number of hospitalizations for coronary, cerebral, or peripheral ischemia through 90 days and time to first occurrence of the composite primary outcome through 180 and 365 days. AEGIS-II will be the first trial to formally test whether enhancing cholesterol efflux can reduce the rate of recurrent major adverse CV events.


Assuntos
Lipoproteínas HDL/uso terapêutico , Infarto do Miocárdio/terapia , Idoso , Isquemia Encefálica/prevenção & controle , Colesterol/metabolismo , Doença da Artéria Coronariana/metabolismo , Diabetes Mellitus/tratamento farmacológico , Método Duplo-Cego , Esquema de Medicação , Hospitalização/estatística & dados numéricos , Humanos , Isquemia/prevenção & controle , Lipoproteínas HDL/administração & dosagem , Lipoproteínas HDL/efeitos adversos , Fígado/metabolismo , Infarto do Miocárdio/prevenção & controle , Isquemia Miocárdica/prevenção & controle , Doenças Vasculares Periféricas/prevenção & controle , Placebos/uso terapêutico , Placa Aterosclerótica/metabolismo , Acidente Vascular Cerebral/prevenção & controle , Fatores de Tempo
14.
World J Gastroenterol ; 26(41): 6402-6413, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33244201

RESUMO

BACKGROUND: Clinically significant post-endoscopic retrograde cholangiopancreatography (ERCP) bacteremia (PEB) occurs in up to 5% of cases, while antibiotic prophylaxis is recommended only when an ERCP is unlikely to achieve complete biliary drainage. However, the current recommendations may not cover all potential risk factors for PEB. AIM: To identify novel risk factors for PEB and evaluate appropriateness of antibiotic prophylaxis. METHODS: A retrospective study of 1082 ERCP procedures performed between January 2012 - December 2013 in a single tertiary medical center. Data collection included: Demographic and clinical characteristics such as pre and post procedure antibiotic treatment and bacterial blood cultures. Exclusion criteria were: (1) Age < 18 years; (2) Positive bacterial blood culture before ERCP; (3) Scheduled antibiotic treatment prior to ERCP; (4) Hospitalization longer than 14 d before ERCP; and (5) missing critical data. Stepwise Logistic Regression analysis and Decision Tree algorithms were used for prediction modeling of PEB. RESULTS: A total of 626 ERCPs performed in 434 patients were included. Mean age 66.49 ± 15.4 years and 46.5% were males. PEB prevalence was 3.7%. Antibiotic prophylaxis was administrated in 139/626 (22.2%) cases but was indicated according to the guidelines only in 44/626 (7%) cases. In all the PEB cases, prophylaxis was deemed not indicated. A stepwise logistic regression [receiver operating characteristic (ROC), 0.766], identified 3 variables as independent risk factors for PEB: Age at ERCP ≥ 75 years (OR, 3.780, 95%CI: 1.519-9.408, P = 0.004); Tandem EUS/ERCP with fine needle aspiration (FNA) (OR, 14.528, 95%CI: 3.571-59.095, P < 0.001); ERCP duration longer than 60 min (OR, 5.396, 95%CI: 1.86-15.656, P = 0.002). In a decision tree model (ROC, 0.778) the probability for PEB without any risk factors was 1% regardless of prophylaxis administration. CONCLUSION: The prevalence of PEB in our study is similar to previous reports, despite the fact that antibiotic prophylaxis was administrated more readily than recommended. ERCP duration longer than 60 min, tandem EUS-ERCP with FNA and age above 75 years are significant risk factors for PEB. These factors should be further evaluated as indications for prophylactic antibiotic treatment before ERCP.


Assuntos
Bacteriemia , Colangiopancreatografia Retrógrada Endoscópica , Adolescente , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Bacteriemia/prevenção & controle , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Endossonografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
15.
ACS Appl Mater Interfaces ; 12(46): 51337-51343, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33146989

RESUMO

Although back-surface passivation plays an important role in high-efficiency photovoltaics, it has not yet been definitively demonstrated for CdTe. Here, we present a solution-based process, which achieves passivation and improved electrical performance when very small amounts of oxidized Al3+ species are deposited at the back surface of CdTe devices. The open circuit voltage (Voc) is increased and the fill factor (FF) and photoconversion efficiency (PCE) are optimized when the total amount added corresponds to ∼1 monolayer, suggesting that the passivation is surface specific. Addition of further Al3+ species, present in a sparse alumina-like layer, causes the FF and PCE to drop as the interface layer becomes blocking to current flow. The optimized deposit increases the average baseline PCE for both Cu-free devices and devices where Cu is present as a dopant. The greatest improvement is found when the Al3+ species are deposited prior to the CdCl2 activation step and Cu is employed. In this case, the best-cell efficiency was improved from 12.6 to 14.4%. Time-resolved photoluminescence measurements at the back surface and quantum efficiency measurements performed at the maximum power point indicate that the performance enhancement is due to a reduction in the interface recombination current at the back surface.

16.
Materials (Basel) ; 13(8)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344645

RESUMO

The replacement of traditional CdS with zinc magnesium oxide (ZMO) has been demonstrated as being helpful to boost power conversion efficiency of cadmium telluride (CdTe) solar cells to over 18%, due to the reduced interface recombination and parasitic light absorption by the buffer layer. However, due to the atmosphere sensitivity of ZMO film, the post treatments of ZMO/CdTe stacks, including CdCl2 treatment, back contact deposition, etc., which are critical for high-performance CdTe solar cells became crucial challenges. To realize the full potential of the ZMO buffer layer, plenty of investigations need to be accomplished. Here, copper thiocyanate (CuSCN) is demonstrated to be a suitable back-contact material with multi-advantages for ZMO/CdTe solar cells. Particularly, ammonium hydroxide as the solvent for CuSCN deposition shows no detrimental impact on the ZMO layer during the post heat treatment. The post annealing temperature as well as the thickness of CuSCN films are investigated. Finally, a champion power conversion efficiency of 16.7% is achieved with an open-circuit voltage of 0.857 V, a short-circuit current density of 26.2 mA/cm2, and a fill factor of 74.0%.

17.
BMC Med Ethics ; 21(1): 8, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964390

RESUMO

BACKGROUND: The progress of electronic health technologies and biobanks holds enormous promise for efficient research. Evidence shows that studies based on sharing and secondary use of data/samples have the potential to significantly advance medical knowledge. However, sharing of such resources for international collaboration is hampered by the lack of clarity about ethical and legal requirements for transfer of data and samples across international borders. MAIN TEXT: Here, the International Clinical Trial Center Network (ICN) reports the legal and ethical requirements governing data and sample exchange (DSE) across four continents. The most recurring requirement is ethical approval, whereas only in specific conditions approval of national health authorities is required. Informed consent is not required in all sharing situations. However, waiver of informed consent is only allowed in certain countries/regions and under certain circumstances. The current legal and ethical landscape appears to be very complex and under constant evolution. Regulations differ between countries/regions and are often incomplete, leading to uncertainty. CONCLUSION: With this work, ICN illuminates the unmet need for a single international collaborative framework to facilitate DSE. Harmonising requirements for global DSE will reduce inefficiency and waste in research. There are many challenges to realising this ambitious vision, including inconsistent terminology and definitions, and heterogeneous and dynamic legal constraints. Here, we identify areas of agreement and significant difference as a necessary first step towards facilitating international collaboration. We propose the establishment of a working group to continue the comparison across jurisdictions, create a standardised glossary and define a set of basic principles and fundamental requirements for DSE.


Assuntos
Registros Eletrônicos de Saúde/ética , Registros Eletrônicos de Saúde/legislação & jurisprudência , Disseminação de Informação/ética , Disseminação de Informação/legislação & jurisprudência , Cooperação Internacional/legislação & jurisprudência , Bancos de Tecidos/ética , Bancos de Tecidos/legislação & jurisprudência , Saúde Global , Humanos , Internacionalidade , Propriedade/ética , Propriedade/legislação & jurisprudência
18.
J Phys Chem Lett ; 9(21): 6312-6320, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30336064

RESUMO

Organic-inorganic metal halide perovskites are notoriously unstable in humid environments. While many studies have revealed the morphology and crystal structure changes that accompany exposure to humidity, little is known about changes to the photophysics that accompany the degradation process. By combining in situ steady-state and time-resolved photoluminescence with Hall effect measurements, we examined the changes in the photoexcited carrier dynamics for methylammonium lead iodide (MAPbI3) and bromide (MAPbBr3) films exposed to nitrogen gas containing water vapor at 80% relative humidity. The changes in the photophysics of MAPbI3 interacting with water follow a four-stage process, consisting of surface passivation, free electron doping, interfacial hydration, and bulk hydration. In contrast, MAPbBr3 exhibits only features associated with the first two stages, which occur at a faster rate. Our results elucidate the degradation mechanisms of perovskite films in high humidity from the perspective of the photophysics, providing insights for how humidity affects the stability of the perovskite materials.

19.
Trials ; 19(1): 581, 2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30352601

RESUMO

BACKGROUND: Mandatory trial registration, and later results reporting, were proposed to mitigate selective clinical trial publication and outcome reporting. The Food and Drug Administration (FDA) Amendments Act (FDAAA) was enacted by Congress on September 27, 2007, requiring the registration of all non-phase I clinical trials involving FDA-regulated medical interventions and results reporting for approved drugs. The association between FDAAA enactment and the registration, results reporting, and publication bias of neuropsychiatric trials has not been studied. METHODS: We conducted a retrospective cohort study of all efficacy trials supporting FDA new drug approvals between 2005 to 2014 for neuropsychiatric indications. Trials were categorized as pre- or post-FDAAA based on initiation and/or completion dates. The main outcomes were the proportions of trials registered and reporting results in ClinicalTrials.gov, and the degree of publication bias, estimated using the relative risks pre- and post-FDAAA of both the publication of positive vs non-positive trials, as well as of publication of positive vs non-positive trials without misleading interpretations. Registration and results reporting proportions were compared pre- and post-FDAAA using the two-tailed Fisher exact test, and the degrees of publication bias were compared by calculating the ratio of relative risks (RRR) for each period. RESULTS: The FDA approved 37 new drugs for neuropsychiatric indications between 2005 and 2014 on the basis of 142 efficacy trials, of which 101 were pre-FDAAA and 41 post-FDAAA. Post-FDAAA trials were significantly more likely to be registered (100% vs 64%; p < 0.001) and report results (100% vs 10%; p < 0.001) than pre-FDAAA trials. Pre-FDAAA, positive trials were more likely to be published (relative risk [RR] = 1.52; 95% confidence interval [CI] = 1.17-1.99; p = 0.002) and published without misleading interpretations (RR = 2.47; CI = 1.57-3.73; p < 0.001) than those with non-positive results. In contrast, post-FDAAA positive trials were equally likely to have been published (RR = 1; CI = 1-1, p = NA) and published without misleading interpretations (RR = 1.20; CI = 0.84-1.72; p = 0.30). The likelihood of publication bias pre-FDAAA vs post-FDAAA was greater for positive vs non-positive trials (RRR = 1.52; CI = 1.16-1.99; p = 0.002) and for publication without misleading interpretations (RRR = 2.06, CI = 1.17-3.61, p = 0.01). CONCLUSIONS: The enactment of FDAAA was followed by significantly higher proportions of trials that were registered and reporting results on ClinicalTrials.gov and significantly lower degrees of publication bias among trials supporting recent FDA approval of drugs for neuropsychiatric indications.


Assuntos
Fármacos do Sistema Nervoso Central/uso terapêutico , Ensaios Clínicos como Assunto/métodos , Aprovação de Drogas , Transtornos Mentais/tratamento farmacológico , Viés de Publicação , Sistema de Registros , Projetos de Pesquisa , United States Food and Drug Administration , Fármacos do Sistema Nervoso Central/efeitos adversos , Confiabilidade dos Dados , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/fisiopatologia , Transtornos Mentais/psicologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
20.
Sci Rep ; 7(1): 16295, 2017 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-29176682

RESUMO

Social norms regulate behavior, and changes in norms have a great impact on society. In most modern societies, norms change through interpersonal communication and persuasive messages found in media. Here, we examined the neural basis of persuasion-induced changes in attitude toward and away from norms using fMRI. We measured brain activity while human participants were exposed to persuasive messages directed toward specific norms. Persuasion directed toward social norms specifically activated a set of brain regions including temporal poles, temporo-parietal junction, and medial prefrontal cortex. Beyond these regions, when successful, persuasion away from an accepted norm specifically recruited the left middle temporal and supramarginal gyri. Furthermore, in combination with data from a separate attitude-rating task, we found that left supramarginal gyrus activity represented participant attitude toward norms and tracked the persuasion-induced attitude changes that were away from agreement.


Assuntos
Comunicação Persuasiva , Normas Sociais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia
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