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1.
Nat Mater ; 23(6): 810-817, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38684883

RESUMO

For halide perovskites that are susceptible to photolysis and ion migration, iodide-related defects, such as iodine (I2) and iodine vacancies, are inevitable. Even a small number of these defects can trigger self-accelerating chemical reactions, posing serious challenges to the durability of perovskite solar cells. Fortunately, before I2 can damage the perovskites under illumination, they generally diffuse over a long distance. Therefore, detrimental I2 can be captured by interfacial materials with strong iodide/polyiodide (Ix-) affinities, such as fullerenes and perfluorodecyl iodide. However, fullerenes in direct contact with perovskites fail to confine Ix- ions within the perovskite layer but cause detrimental iodine vacancies. Perfluorodecyl iodide, with its directional Ix- affinity through halogen bonding, can both capture and confine Ix-. Therefore, inverted perovskite solar cells with over 10 times improved ultraviolet irradiation and thermal-light stabilities (under 85 °C and 1 sun illumination), and 1,000 times improved reverse-bias stability (under ISOS-V ageing tests) have been developed.

2.
Phys Chem Chem Phys ; 26(6): 5027-5037, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38258478

RESUMO

Organometal halide perovskites are promising materials for optoelectronic applications, whose commercial realization depends critically on their stability under multiple environmental factors. In this study, a methylammonium lead bromide (MAPbBr3) single crystal was cleaved and exposed to simultaneous oxygen and light illumination under ultrahigh vacuum (UHV). The exposure process was monitored using X-ray photoelectron spectroscopy (XPS) with precise control of the exposure time and oxygen pressure. It was found that the combination of oxygen and light accelerated the degradation of MAPbBr3, which could not be viewed as a simple addition of that by oxygen-only and light-only exposures. The XPS spectra showed significant loss of carbon, bromine, and nitrogen at an oxygen exposure of 1010 Langmuir with light illumination, approximately 17 times of the additive effects of oxygen-only and light-only exposures. It was also found that the photoluminescence (PL) emission was much weakened by oxygen and light co-exposure, while previous reports had shown that PL was substantially enhanced by oxygen-only exposure. Measurements using a scanning electron microscope (SEM) and focused ion beam (FIB) demonstrated that the crystal surface was much roughened by the co-exposure. Density functional theory (DFT) calculations revealed the formation of superoxide and oxygen induced gap state, suggesting the creation of oxygen radicals by light illumination as a possible microscopic driving force for enhanced degradation.

3.
Endocr Pract ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38876178

RESUMO

OBJECTIVE: Continuous glucose monitoring (CGM) may have benefits in achieving glycemic control in critically ill patients. The aim of this study was to assess the accuracy of the Freestyle Libre H (professional version of the Libre Pro). in patients with acute respiratory failure (ARF) in the intensive care unit (ICU). METHODS: 52 adult patients with ARF were selected. The performance of CGM was evaluated using arterial blood glucose (aBG) and point-of-care (POC) glucose as reference values. Numerical accuracy was evaluated by the mean absolute relative difference (MARD), Bland-Altman analysis, and %15/15(the percentage of CGM values within 15 mg/dL or 15% of reference values <100 mg/dL or >100mg/dL, respectively), %20/20 and %30/30; Clinical accuracy was assessed by Clarke error grid analysis. RESULTS: 519 and 1504 pairs of aBG/CGM and POC/CGM glucose values were analyzed. The MARD values were 13.8% and 14.7%, respectively. The mean deviation of the Bland‒Altman analysis was 0.82 mmol/L and 0.81 mmol/L. %15/15, %20/20 and %30/30 of aBG values were 62.6%, 75.5%, and 92.4%, respectively; %15/15, %20/20 and %30/30 of POC values were 57.1%, 72.9%, and 88.7%, respectively. The Clarke error grid analysis showed that 97.8% and 99.3% of the values located in the (A+B) zone. Additionally, accuracy of CGM is not affected by general patient factors. CONCLUSION: This study demonstrated that the accuracy of CGM in patients with ARF is lower than that in most outpatients, and it is not affected by general patient factors. Whether CGM is beneficial to glucose management in ICU needs further evaluation.

4.
J Chem Inf Model ; 63(9): 2742-2747, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37094567

RESUMO

This study demonstrates the determination of reaction pathways by evaluating the carbon kinetic isotopic effect and interpreting isotopic fractionations based on quantum chemical calculations. The reaction under investigation is methane thermogenesis from the decomposition of kerogen, which is a geochemical reaction under temperatures below 150 °C and lasts for tens of millions of years. Investigating its mechanism requires theoretical simulations because lab experiments at practical time-lengths require elevated temperatures, which introduce unwanted side reactions. Density functional theory and kinetic simulations were conducted on isotopic fractionations with the use of two possible pathways (free-radical versus carbonium), and the results were compared to field data sets. Different molecular sizes of kerogen were investigated to account for the hindrance of translation and rotation in modeling a reactant in the solid phase. Both pathways have low reaction barriers, implying that the reaction rates are limited by the concentration of active species (hydrated protons and free radicals). The results support the carbonium pathway and rule out the free-radical pathway as the 13CH4 from the latter would be 30‰ more depleted than the observed data. Additionally, simulations were conducted on hydrocarbon isotope fractionation of the carbonium pathway with consideration of hydrogen exchange between methane and water, successively reproducing the observed abundances of deuterium-containing isotopologues (13CH3D, 13CH3D, and 12CH2D2).


Assuntos
Metano , Temperatura , Cinética , Isomerismo , Metano/química , Isótopos de Carbono
5.
Am J Emerg Med ; 73: 131-136, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657142

RESUMO

OBJECTIVES: Older patients arrive at the emergency department (ED) with complex medical challenges, and the current ED triage models frequently undertriage the severity of illness in older adults. There is increasing awareness regarding the importance of identifying frailty in older patients in the context of urgent care. Therefore, this study aimed to assess the predictive accuracy of the seven-question tool of the Program on Research for Integrating Services of the Maintenance of Autonomy (PRISMA-7) in the ED for 28-day mortality among older adults. DESIGN: A prospective polycentric observational study. SETTING: West China Hospital of Sichuan University, Shangjinnanfu of West China Hospital, and People's Hospital of Henan Province. PARTICIPANTS: ED patients aged ≥65 years from the three tertiary care centers over an 8-week period. PRIMARY AND SECONDARY OUTCOMES: The primary outcome, 28-day all-cause mortality, was investigated using a Cox proportional hazards regression model to assess the predictive validity. The secondary endpoints, intensive care unit (ICU) transfer was investigated using multivariable logistic regression, compared with trained study assistants. RESULTS: The final study population comprised 1043 consecutive patients aged ≥65 years. The area under the receiver operating characteristic (ROC) curve (AUC) for 28-day mortality was 0.80 (95% confidence interval [CI]: 0.76-0.84), 0.73 (95% CI: 0.68-0.77), and 0.78 (95% CI: 0.73-0.83) for PRISMA-7, Emergency Severity Index (ESI), and quick Sepsis Related Organ Failure Assessment (qSOFA), respectively.There was no difference in the AUC between PRISMA-7 and qSOFA(p = 0.374).The AUC for ICU admission was 0.78 (95% CI: 0.75-0.80), 0.62 (95% CI: 0.59-0.66), and 0.68 (95% CI: 0.64-0.72) for PRISMA-7, ESI, and qSOFA, respectively.The AUC for ICU admission between PRISMA-7 and ESI(p<0.001), PRISMA-7 and qSOFA(p<0.001), qSOFA and ESI(p = 0.005) was statistically significant. CONCLUSION: Our findings reveal that PRISMA-7 improves the prediction of ICU admission, but there is no significant difference when it comes to all-cause mortality. PRISMA-7 appears to be a reliable and valid instrument for identifying frailty in the ED. TRIAL REGISTRATION NUMBER: ChiCTR2100046545.

6.
Nurs Crit Care ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905383

RESUMO

OBJECTIVE: To identify the validity and predictability of the confusion assessment method for the intensive care unit (CAM-ICU) for delirium in critically ill patients in the ICU. METHODS: In this systematic review, PubMed, Embase, Cochrane Central Register of Controlled Trials, and MEDLINE databases were searched for observational studies investigating delirium screening tools for ICU patients. In the meta-analysis, we combined the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve (AUC) of SROC to analysis the predictive value of CAM-ICU. RESULTS: Twenty-nine articles met the inclusion criteria. The pooled sensitivity and specificity values were 0.82 (95% confidence interval [CI]: 0.75-0.87) and 0.95 (95% CI: 0.93-0.97), respectively. The AUC point estimate of the SROC curve was 0.96 (95% CI: 0.94-0.97). Race (Asian or Others) could affect the pooled sensitivity and specificity, and the analysis method (Patient- or Scan-based) and study design were not sources of heterogeneity for pooled sensitivity and specificity. CONCLUSIONS: The CAM-ICU is a valid and reliable tool for delirium prediction among ICU patients. When introducing CAM-ICU to assess delirium, it is necessary to localize its language and content to improve its predictive efficacy in different countries and different ethnic groups. RELEVANCE TO CLINICAL PRACTICE: In clinical practice, nurses can use CAM-ICU to evaluate delirium in critically ill patients in ICU. However, it is necessary to debug the language and content according to the application population.

7.
Angew Chem Int Ed Engl ; 62(24): e202303176, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37060295

RESUMO

Possessed with advantageous optoelectronic properties, perovskites have boosted the rapid development of solution-processed solar cells. The performance of perovskite solar cells (PSCs) is significantly weakened by the carrier loss at grain boundary grooves (GBGs); however, it receives limited attention and there lacks effective approach to solve this issue. Herein, for the first time, we constructed the tungstate/perovskite heterointerface via a "two step" in situ reaction approach that provides effective defect passivation and ensures efficient carrier dynamics at the GBGs. The exposed perovskite at grain boundaries is converted to wide-band-gap PbWO4 via an in-situ reaction between Pb2+ and tungstate ions, which passivate defects due to the strong ionic bonding. Moreover, recombination loss is further suppressed via the heterointerface energetics modification based on an additional transformation from PbWO4 to CaWO4 . PSCs based on this groove modification strategy showed good universality in both normal and inverted structure, with an improved efficiency of 23.25 % in the n-i-p device and 23.33 % in the p-i-n device. Stable power output of the modified device could maintain 91.7 % after around 1100 h, and the device efficiency could retain 92.5 % after aging in air for around 2110 h, and 93.1 % after aging at 85 °C in N2 for 972 h.

8.
J Am Chem Soc ; 144(7): 3039-3049, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35112839

RESUMO

Electrochemical CO2 reduction is a promising way to mitigate CO2 emissions and close the anthropogenic carbon cycle. Among products from CO2RR, multicarbon chemicals, such as ethylene and ethanol with high energy density, are more valuable. However, the selectivity and reaction rate of C2 production are unsatisfactory due to the sluggish thermodynamics and kinetics of C-C coupling. The electric field and thermal field have been studied and utilized to promote catalytic reactions, as they can regulate the thermodynamic and kinetic barriers of reactions. Either raising the potential or heating the electrolyte can enhance C-C coupling, but these come at the cost of increasing side reactions, such as the hydrogen evolution reaction. Here, we present a generic strategy to enhance the local electric field and temperature simultaneously and dramatically improve the electric-thermal synergy desired in electrocatalysis. A conformal coating of ∼5 nm of polytetrafluoroethylene significantly improves the catalytic ability of copper nanoneedles (∼7-fold electric field and ∼40 K temperature enhancement at the tips compared with bare copper nanoneedles experimentally), resulting in an improved C2 Faradaic efficiency of over 86% at a partial current density of more than 250 mA cm-2 and a record-high C2 turnover frequency of 11.5 ± 0.3 s-1 Cu site-1. Combined with its low cost and scalability, the electric-thermal strategy for a state-of-the-art catalyst not only offers new insight into improving activity and selectivity of value-added C2 products as we demonstrated but also inspires advances in efficiency and/or selectivity of other valuable electro-/photocatalysis such as hydrogen evolution, nitrogen reduction, and hydrogen peroxide electrosynthesis.

9.
BMC Geriatr ; 22(1): 321, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413794

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is associated with a greater frailty risk, but it remains unknown if pathways that contribute to CVD are associated with the frailty risk. Thus, we aimed to investigate whether elevations in high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for those without known CVD at baseline are associated with a higher frailty risk. METHODS: This study used data from the Atherosclerosis Risk in Communities study. Cardiac biomarkers were measured from stored plasma samples collected at Visit 2 (1991-1993). Frailty was recorded at Visit 5 (2011-2013). Cox regression models were used to determine the association of cardiac biomarkers with frailty risk. RESULTS: Overall, 360/5199 (6.9%) participants aged 55.1 ± 5.1 years developed frailty during a median follow-up of 21.7 years. The incidence of frailty was significantly higher in participants with hs-cTnT ≥14 ng/L (vs. < 14 ng/L: 17.9% vs. 6.7%) or NT-proBNP ≥300 pg/ml (vs. < 300 pg/ml: 19.7% vs. 6.8%) (all P < 0.001). Comparing higher vs. lower cut-off levels of either hs-cTnT (14 ng/l) or NT-proBNP (300 pg/ml) demonstrated a greater than two-fold higher frailty risk, with hazard ratios (HRs) of 2.13 (95% confidence interval (CI): 1.130-4.01, P = 0.020) and 2.61 (95% CI: 1.28-5.33, P = 0.008), respectively. Individuals with both elevated hs-cTnT and NT-proBNP had a higher frailty risk than those without it (HR: 4.15; 95% CI: 1.50-11.48, P = 0.006). CONCLUSIONS: High hs-cTnT and NT-proBNP levels are strongly associated with incident frailty in the community-dwelling population without known CVD. Subclinical cardiac damage (hs-cTnT) and/or wall strain (NT-proBNP) may be the key pathway of CVD patients developing frailty. Detection of hs-cTnT and NT-proBNP may help for early screening of high-risk frailty and providing individualised intervention. TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique identifier: NCT00005131 .


Assuntos
Aterosclerose , Doenças Cardiovasculares , Fragilidade , Aterosclerose/diagnóstico , Aterosclerose/epidemiologia , Biomarcadores , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Fragilidade/complicações , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Humanos , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Fatores de Risco , Troponina T
10.
Proc Natl Acad Sci U S A ; 116(35): 17201-17206, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31405969

RESUMO

Tropical rainfall variability is closely linked to meridional shifts of the Intertropical Convergence Zone (ITCZ) and zonal movements of the Walker circulation. The characteristics and mechanisms of tropical rainfall variations on centennial to decadal scales are, however, still unclear. Here, we reconstruct a replicated stalagmite-based 2,700-y-long, continuous record of rainfall for the deeply convective northern central Indo-Pacific (NCIP) region. Our record reveals decreasing rainfall in the NCIP over the past 2,700 y, similar to other records from the northern tropics. Notable centennial- to decadal-scale dry climate episodes occurred in both the NCIP and the southern central Indo-Pacific (SCIP) during the 20th century [Current Warm Period (CWP)] and the Medieval Warm Period (MWP), resembling enhanced El Niño-like conditions. Further, we developed a 2,000-y-long ITCZ shift index record that supports an overall southward ITCZ shift in the central Indo-Pacific and indicates southward mean ITCZ positions during the early MWP and the CWP. As a result, the drying trend since the 20th century in the northern tropics is similar to that observed during the past warm period, suggesting that a possible anthropogenic forcing of rainfall remains indistinguishable from natural variability.

11.
Small ; 17(32): e2102368, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34174144

RESUMO

Flexible perovskite solar cells (f-PSCs) have been attracting tremendous attention due to their potentially commercial prospects in flexible energy system and mobile energy system. Reducing the energy barriers and charge extraction losses at the interfaces between perovskite and charge transport layers is essential to improve both efficiency and stability of f-PSCs. Herein, 4-trifluoromethylphenylethylamine iodide (CF3 PEAI) is introduced to form a 2D perovskite at the interface between perovskite and hole transport layer (HTL). It is found that the 2D perovskite plays a dual-functional role in aligning energy band between perovskite and HTL and passivating the traps in the 3D perovskite, thus reducing energy loss and charge carrier recombination at the interface, facilitating the hole transfer from perovskite to the Spiro-OMeTAD. Consequently, the photovoltaic performance of f-PSCs is significantly improved, leading to a power conversion efficiency (PCE) of 21.1% and a certified PCE of 20.5%. Furthermore, the long-term stability of f-PSCs is greatly improved through the protection of 2D perovskite layer to the underlying 3D perovskite. This work provides an excellent strategy to produce efficient and stable f-PSCs, which will accelerate their potential applications.

12.
J Transl Med ; 19(1): 12, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407592

RESUMO

BACKGROUND: Prostate cancer (PCa) is a leading cause of cancer-related death in males. Aberrant expression of long non-coding RNAs (lncRNAs) has been implicated in various human malignancies, including PCa. This study aims to clarify the inhibitory role of human PGM5 antisense RNA 1 (PGM5-AS1) in the proliferation and apoptosis of PCa cells. METHODS: The regulatory network of PGM5-AS1/microRNA-587 (miR-587)/growth and differentiation factor 10 (GDF10) axis was examined by dual-luciferase reporter gene assay, RNA-binding protein immunoprecipitation, and RNA pull down assay. We manipulated the expression of PGM5-AS1, miR-587 and GDF10 by transducing expression vectors, mimic, inhibitor, or short hairpin RNA into PCa cells, thus establishing their functions in cell proliferation and apoptosis. Additionally, we measured the tumorigenicity of PCa cells xenografted in nude mice. RESULTS: PGM5-AS1 is expressed at low levels in PCa cell lines. Forced overexpression of PGM5-AS1 restricted proliferation and facilitated apoptosis of PCa cells, manifesting in suppressed xenograft tumor growth in nude mice. Notably, PGM5-AS1 competitively bound to miR-587, which directly targets GDF10. We further validated that the anti-cancer role of PGM5-AS1 in PCa cells was achieved by binding to miR-587 to promote the expression of GDF10. CONCLUSION: PGM5-AS1 upregulates GDF10 gene expression by competitively binding to miR-587, thus inhibiting proliferation and accelerating apoptosis of PCa cells.


Assuntos
MicroRNAs , Neoplasias da Próstata , RNA Longo não Codificante , Animais , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Fator 10 de Diferenciação de Crescimento , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Neoplasias da Próstata/genética , RNA Longo não Codificante/genética
13.
Phys Chem Chem Phys ; 23(16): 9631-9642, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33870992

RESUMO

Organic semiconductor thin films based on polycrystalline small molecules exhibit many attractive properties that have already led to their applications in optoelectronic devices, which can be produced by less expensive and stringent processes. Conduction of electric charges typically occurs in polycrystalline organic thin films. Unavoidably, the crystalline domain size, orientation, domain boundaries and energy level of the interface affect the transport of the charge carriers in organic thin films. In this comprehensive perspective, we focus on highly ordered organic heterojunction thin films fabricated by the weak epitaxy growth method. Transport of charge carriers in these highly ordered organic heterojunction thin films was systematically studied with various characterization techniques. Recent advances are presented in high-performance optoelectronic applications based on highly ordered organic heterojunction thin films, including organic photodetectors, photovoltaic cells, photomemory devices and artificial optoelectronic synapses.

14.
Nutr Metab Cardiovasc Dis ; 31(4): 1121-1128, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33573920

RESUMO

BACKGROUND AND AIMS: Acute kidney injury (AKI) is a common complication of acute coronary syndrome (ACS), and is associated with increased risk of morbidity and mortality. We aimed to evaluate the impact of malnutrition risk at admission assessed using Nutritional Risk Screening 2002 (NRS-2002) on AKI and mortality in patients with ACS. METHODS AND RESULTS: We enrolled 3185 ACS patients from the retrospective multi-centre study. AKI was defined as criteria of the 2012 Kidney Disease Improving Global Outcomes. Risk of malnutrition was defined as NRS-2002 score ≥3. The end points were AKI and all-cause mortality. There were 926 (29.1%) patients with risk of malnutrition and 481 (15.1%) patients complicated with AKI during hospitalisation, and 378 (12.0%) patients died during the 13.1 (8.5-20.4) months of follow-up. Patients with NRS-2002 score ≥3 had a higher incidence of AKI and all-cause mortality (P < 0.001). Multivariate logistic and Cox regression analysis showed that the adjusted odd ratios and hazard ratios of categorised NRS-2002 (<3 vs. ≥3) for AKI and mortality were 1.643 (95% confidence interval: 1.242-2.172, P < 0.001) and 2.026 (95% confidence interval: 1.491-2.753, P < 0.001), respectively. In structural equation modelling, the indirect effects of NRS-2002 on mortality via AKI were 54.1% (P < 0.001). CONCLUSION: The risk of malnutrition assessed using NRS-2002 was useful in identifying high-risk patients with AKI and mortality, and patients with ACS may benefit from further nutritional intervention and prevention of AKI. REGISTRATION NUMBER: ChiCTR1900024657.


Assuntos
Síndrome Coronariana Aguda/terapia , Injúria Renal Aguda/mortalidade , Desnutrição/diagnóstico , Avaliação Nutricional , Estado Nutricional , Intervenção Coronária Percutânea/mortalidade , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/mortalidade , Injúria Renal Aguda/diagnóstico , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Desnutrição/mortalidade , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Admissão do Paciente , Intervenção Coronária Percutânea/efeitos adversos , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
15.
Mar Drugs ; 19(8)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34436267

RESUMO

The mangrove-sediment-derived actinomycete strain Streptomyces psammoticus SCSIO NS126 was found to have productive piericidin metabolites featuring anti-renal cell carcinoma activities. In this study, in order to explore more diverse piericidin derivatives, and therefore to discover superior anti-tumor lead compounds, the NS126 strain was further fermented at a 300-L scale under optimized fermentation conditions. As a result, eight new minor piericidin derivatives (piericidins L-R (1-7) and 11-demethyl-glucopiericidin A (8)) were obtained, along with glucopiericidin B (9). The new structures including absolute configurations were determined by spectroscopic methods coupled with experimental and calculated electronic circular dichroism. We also proposed plausible biosynthetic pathways for these unusual post-modified piericidins. Compounds 1 and 6 showed selective cytotoxic activities against OS-RC-2 cells, and 2-5 exhibited potent cytotoxicity against HL-60 cells, with IC50 values lower than 0.1 µM. The new piericidin glycoside 8 was cytotoxic against ACHN, HL-60 and K562, with IC50 values of 2.3, 1.3 and 5.5 µM, respectively. The ability to arrest the cell cycle and cell apoptosis effects induced by 1 and 6 in OS-RC-2 cells, 2 in HL-60 cells, and 8 in ACHN cells were then further investigated. This study enriched the structural diversity of piericidin derivatives and confirmed that piericidins deserve further investigations as promising anti-tumor agents.


Assuntos
Aminoglicosídeos/farmacologia , Antineoplásicos/farmacologia , Organismos Aquáticos/química , Streptomyces/química , Aminoglicosídeos/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos
16.
J Cardiovasc Nurs ; 36(6): 546-555, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605639

RESUMO

BACKGROUND: The Nutritional Risk Screening 2002 (NRS-2002) scale is a rapid and effective screening instrument that assesses nutritional risk among hospitalized patients. OBJECTIVE: The present study aimed to explore the prognostic value of the NRS-2002 scale in acute myocardial infarction (AMI) considering its uncertain role in this particular condition. METHODS: Patients with AMI included in the Retrospective Multicenter Study for Early Evaluation of Acute Chest Pain were investigated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to analyze the association between NRS-2002 and mortality in patients with AMI. The primary and secondary endpoints were all-cause and cardiac mortality during the follow-up period. RESULTS: A total of 2307 patients were enrolled, among whom 246 (10.7%) died within a median follow-up duration of 10.67 (8.04-14.33) months. Kaplan-Meier analysis revealed that patients with an NRS-2002 score of 3 or higher had poorer cumulative survival than those with an NRS-2002 score lower than 3 (P < .001). In the multivariate Cox regression analysis, patients with an NRS-2002 score of 3 or higher had more than double the risk for all-cause mortality (hazard ratio, 2.25; 95% confidence interval, 1.50-3.40; P < .001) and twice the risk for cardiac-related mortality (hazard ratio, 2.01; 95% confidence interval, 1.29-3.13; P = .002) than did patients with lower scores. CONCLUSIONS: Our results showed that the NRS-2002 screening instrument was an independent prognostic predictor for both all-cause and cardiac mortality in patients with AMI. Nutritional risk assessment based on the NRS-2002 scale may provide useful prognostic information of early nutritional risk stratification in patients with AMI.


Assuntos
Infarto do Miocárdio , Pesquisa , Dor no Peito/diagnóstico , Dor no Peito/etiologia , Humanos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Prognóstico , Estudos Retrospectivos
17.
J Nurs Manag ; 29(7): 2189-2198, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33993569

RESUMO

AIM: To analyse the frequency and core elements of nursing work interruptions in Chinese emergency nursing settings. BACKGROUND: Little is known about nursing interruptions, which affect the quality of services in Chinese emergency nursing setting. METHOD(S): A cross-sectional observational study was conducted in three units of an emergency department in a Chinese tertiary hospital. Participants comprised 60 nurses. Data were collected using a questionnaire developed by the researchers specifically for this study. RESULTS: In total, 25,965 min of work was observed and 2333 interruptions were identified. Most interruptions were from patients, their families and nurses. Therapeutic nursing and patient observation and documentation were the most frequently interrupted procedures. Most interruptions were negative, and a majority of the nurses immediately responded to interruptions. Significant differences existed in the overall distribution of the core elements among the three nursing units. CONCLUSIONS: The frequency of emergency nursing interruptions was moderate. Most interruptions tend to lead to negative treatment outcomes for patients. IMPLICATIONS FOR NURSING MANAGEMENT: Emergency nursing managers should recognize the importance of interruptions, understand work situations better and develop ways to reduce the incidence of interruptions. Thus, nursing risks can be avoided by reducing the adverse outcomes caused by work interruptions.


Assuntos
Enfermagem em Emergência , Serviço Hospitalar de Emergência , China , Estudos Transversais , Humanos , Inquéritos e Questionários
18.
J Am Chem Soc ; 142(8): 3989-3996, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32031790

RESUMO

State-of-the-art, high-performance perovskite solar cells (PSCs) contain a large amount of iodine to realize smaller bandgaps. However, the presence of numerous iodine vacancies at the surface of the film formed by their evaporation during the thermal annealing process has been broadly shown to induce deep-level defects, incur nonradiative charge recombination, and induce photocurrent hysteresis, all of which limit the efficiency and stability of PSCs. In this work, modifying the defective surface of perovskite films with cadmium iodide (CdI2) effectively reduces the degree of surface iodine deficiency and stabilizes iodine ions via the formation of strong Cd-I ionic bonds. This largely reduces the interfacial charge recombination loss, yielding a high efficiency of 21.9% for blade-coated PSCs with an open-circuit voltage of 1.20 V, corresponding to a record small voltage deficit of 0.31 V. The CdI2 surface treatment also improves the operational stability of the PSCs, retaining 92% efficiency after constant illumination at 1 sun intensity for 1000 h. This work provides a promising strategy to optimize the surface/interface optoelectronic properties of perovskites for more efficient and stable solar cells and other optoelectronic devices.

19.
Phys Chem Chem Phys ; 22(43): 25264-25271, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33135703

RESUMO

X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), atomic force microscopy (AFM) and X-ray diffraction (XRD) were applied to investigate the electronic structure and molecular packing of C8-BTBT on HOPG with an ultrathin C60 interlayer. It was found that C8-BTBT displays a Vollmer-Weber (V-W) growth mode on HOPG, with an ultrathin C60 interlayer (0.7 nm). Compared to the uniform lying-down growth mode as directly grown on HOPG, the C8-BTBT molecules here adopt a lying-down orientation at low coverage with some small tilt angles because the π-π interaction between C8-BTBT and HOPG is partly disturbed by the C60 interlayer, delivering a higher highest occupied molecular orbital (HOMO) in C8-BTBT. An interface dipole of 0.14 eV is observed due to electron transport from C8-BTBT to C60. The upward and downward band bending in C8-BTBT and C60, respectively, near the C8-BTBT/C60 interface reduces the hole transport barrier at the interface, facilitating the hole injection from C60 to C8-BTBT, while a large electron transfer barrier from C60 to C8-BTBT is detected at this interface, which effectively limits electron injection from C60 to C8-BTBT. The HOMO of C8-BTBT near the interface is largely lifted up by the C60 insertion layer, which causes a p-doping effect and increases the hole mobility in C8-BTBT. Furthermore, owing to the lowest occupied molecular orbital (LUMO) of C60 residing in the gap of C8-BTBT, charge transfer occurs between C60 and the trap states in C8-BTBT to effectively passivate the trapping states. Our efforts aid a better understanding of the electron structure and film growth of anisotropic molecules and provide a useful strategy to improve the performance of C8-BTBT-based devices.

20.
Proc Natl Acad Sci U S A ; 114(43): 11297-11302, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29073047

RESUMO

The present study reports the fabrication of CdSe quantum dot (QD)-sensitized photocathodes on NiO-coated indium tin oxide (ITO) electrodes and their H2-generating ability upon light irradiation. A well-established spin-coating method was used to deposit CdSe QD stock solution onto the surface of NiO/ITO electrodes, thereby leading to the construction of various CdSe QD-sensitized photocathodes. The present report includes the construction of rainbow photocathodes by spin-coating different-sized QDs in a sequentially layered manner, thereby creating an energetically favorable gradient for charge separation. The resulting rainbow photocathodes with forward energetic gradient for charge separation and subsequent electron transfer to a solution-based hydrogen-evolving catalyst (HEC) exhibit good light-harvesting ability and enhanced photoresponses compared with the reverse rainbow photocathodes under white LED light illumination. Under minimally optimized conditions, a photocurrent density of as high as 115 µA⋅cm-2 and a Faradaic efficiency of 99.5% are achieved, which is among the most effective QD-based photocathode water-splitting systems.

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