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1.
Nano Lett ; 24(18): 5647-5655, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38655813

RESUMO

Anisotropic nanocrystals such as nanorods (NRs) display unique linearly polarized emission, which is expected to break the external quantum efficiency (EQE) limit of quantum dot-based light-emitting diodes (LEDs). However, the progress in achieving a higher EQE using NRs encounters several challenges, primarily involving a low photoluminescence quantum yield (PLQY) of NRs and imbalanced charge injection in NR-LEDs. In this work, we investigated NR-LEDs based on CdSe/CdZnS/ZnS rod-in-rod NRs with a high PLQY and higher linear polarization compared to those of dot-in-rod NRs. The balanced charge injection is achieved using ZnMgO nanoparticles as the electron transport layer and poly-TPD {poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine]} as the hole transport layer. Therefore, the NR-LEDs exhibit a maximum EQE of 21.5% and a maximum luminance of >120 000 cd/m2 owing to the high level of in-plane transitions with a dipole moment of 90%. The NR-LEDs also have greatly inhibited droop in EQE under a high current density as well as outstanding operation lifetime and cycle stability.

2.
Adv Mater ; 36(19): e2310705, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38377984

RESUMO

The external quantum efficiency (EQE) in light-emitting diodes (LEDs) based on isotropic quantum dots has approached the theoretical limit of close to 20%. Anisotropic nanorods can break this limit by taking advantage of their directional emission. However, the progress towards higher EQE by using CdSe/CdS nanorods (NRs) faces several challenges, primarily involving the low quantum yield and unbalanced charge injection in devices. Herein, the seeded growth method is modified and anisotropic nanorods are obtained with photoluminescence quantum yield up to 98% by coating a gradient alloyed CdZnSe shell around conventional spherical CdSe seeds. This intermediate alloyed CdZnSe shell combined with a subsequent rod-shaped CdZnS/ZnS shell can effectively suppress the electron delocalization in the typical CdSe/CdS nanorods due to their small conduction bandgap offset. Additionally, this alloyed shell can reduce the hole-injection barrier and create a larger barrier for electron injection, both effects promoting a balanced injection of electrons and holes in LEDs. Hence, LEDs are reached with high brightness (160341 cd m-2) and high efficiency (EQE = 22%, current efficiency = 23.19 cd A-1), which are the highest values to date for nanorod LEDs.

3.
Nano Lett ; 23(14): 6689-6697, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37405429

RESUMO

Quantum dot (QD) based light-emitting diodes (QLEDs) hold great promise for next-generation lighting and displays. In order to reach a wide color gamut, deep red QLEDs emitting at wavelengths beyond 630 nm are highly desirable but have rarely been reported. Here, we synthesized deep red emitting ZnCdSe/ZnSeS QDs (diameter ∼16 nm) with a continuous gradient bialloyed core-shell structure. These QDs exhibit high quantum yield, excellent stability, and a reduced hole injection barrier. The QLEDs based on ZnCdSe/ZnSeS QDs have an external quantum efficiency above 20% in the luminance range of 200-90000 cd m-2 and a record T95 operation lifetime (time for the luminance to decrease to 95% of its initial value) of more than 20000 h at a luminance of 1000 cd m-2. Furthermore, the ZnCdSe/ZnSeS QLEDs have outstanding shelf stability (>100 days) and cycle stability (>10 cycles). The reported QLEDs with excellent stability and durability can accelerate the pace of QLED applications.

4.
Cancer Control ; 29: 10732748221124519, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36039467

RESUMO

PURPOSE: The aim of the present study was to develop a nomogram for prognostic prediction of patients with lung cancer in hospice. METHODS: The data was collected from 1106 lung cancer patients in hospice between January 2008 and December 2018. The data were split into a training set, which was used to identify the most important prognostic factors by the least absolute shrinkage and selection operator (LASSO) and to build the nomogram, while the testing set was used to validate the nomogram. The performance of the nomogram was assessed by c-index, calibration curve and the decision curve analysis (DCA). RESULTS: A total of 1106 patients, including 835 (75%) from the training set and 271 (25%) from testing set, were retrospectively analyzed in this study. Using the LASSO regression, 5 most important prognostic predictors that included sex, Karnofsky Performance Scale (KPS), quality-of-life (QOL), edema and anorexia, were selected out of 28 variables. Validated c-indexes of training set at 15, 30, and 90 days were .778 [.737-.818], .776 [.743-.809], and .751 [.713-.790], respectively. Similarly, the validated c-indexes of testing set at 15, 30, and 90 days were .789 [.714-.864], .748 [.685-.811], and .757 [.691-.823], respectively. The nomogram-predicted survival was well calibrated, as the predicted probabilities were close to the expected probabilities. Moreover, the DCA curve showed that nomogram received superior standardized net benefit at a broad threshold. CONCLUSIONS: The study built a non-lab nomogram with important predictor to analyze the clinical parameters using LASSO. It may be a useful tool to allow clinicians to easily estimate the prognosis of the patients with lung cancer in hospice.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Hospitais para Doentes Terminais , Neoplasias Pulmonares , Algoritmos , Humanos , Neoplasias Pulmonares/terapia , Qualidade de Vida , Estudos Retrospectivos
5.
Nanoscale ; 14(18): 6743-6760, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35470846

RESUMO

Radiation detectors are widely used in physics, materials science, chemistry, and biology. Halide perovskites are known for their superior properties including tunable bandgaps and chemical compositions, high defect tolerance, solution-processable synthesis of films and crystals, and high carrier diffusion length. Recently, halide perovskites have attracted enormous interest as particle radiation detectors for both charged (α and ß) and uncharged (neutrons) particles. Solid-state detectors based on single crystal perovskites can detect α particles and thermal neutrons with energy-resolved spectra. Halide perovskite scintillators are also able to detect ß particles and fast neutrons. In this review, we briefly introduce the fundamentals of radiation detection and summarize the recent progress on halide perovskite detectors for particle radiation.

6.
Comput Biol Med ; 141: 105126, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34971976

RESUMO

With the excessive use of smartphones, cervical spine pain is becoming increasingly prevalent. A denoised cervical spine popping sound can aid in monitoring and estimating the state of the cervical spine. However, cervical spine popping sounds that are collected when a subject performs neck movements is contaminated by constant noise. Therefore, a denoising algorithm called Wavelet Transform-Based Stationary-Nonstationary (WTST-NST) is adopted to remove the noise. The input signal is decomposed using wavelet transform to obtain the wavelet coefficients. The wavelet coefficients are then separated into two parts, the nonstationary part and the stationary part, using stationary-nonstationary filtering technology. Finally, the wavelet coefficients of the nonstationary part are reconstructed to obtain the denoised cervical spine popping sound. In addition, the frequency components of the sound are analyzed using the multiresolution analysis of the wavelet transform. The experimental results demonstrate that the implementation of the WTST-NST algorithm in the sound analysis of cervical spine facet joints efficiently reduces the overlapped noise, producing an almost pure cervical spine popping sound. Furthermore, the frequency components of cervical spine popping sounds during the smartphone use period are significantly higher than that in the non-use period and are significantly associated with self-reported neck and upper back pain during the smartphone use period. Therefore, the WTST-NST algorithm preserved almost all the features of the sampled input signal. The denoised cervical spine popping sound can be used to quickly and conveniently monitor the status of the cervical spine during the smartphone use period.


Assuntos
Vértebras Cervicais , Análise de Ondaletas , Algoritmos , Humanos , Som
7.
Sci Total Environ ; 804: 150129, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798726

RESUMO

Mechanical ventilation systems are used in residences to introduce ventilation air and dilute indoor-generated pollutants. A variety of ventilation system types can be used in home retrofits, influencing indoor air quality (IAQ) in different ways. Here we describe the Breathe Easy Project, a >2-year longitudinal, pseudo-randomized, crossover study designed to assess IAQ and adult asthma outcomes before and after installing residential mechanical ventilation systems in 40 existing homes in Chicago, IL. Each home received one of three types of ventilation systems: continuous exhaust-only, intermittent powered central-fan-integrated-supply (CFIS), or continuous balanced system with an energy recovery ventilator (ERV). Homes with central heating and/or cooling systems also received MERV 10 filter replacements. Approximately weeklong field measurements were conducted at each home on a quarterly basis throughout the study to monitor environmental conditions, ventilation operation, and indoor and outdoor pollutants, including size-resolved particles (0.3-10 µm), ozone (O3), nitrogen dioxide (NO2), carbon dioxide (CO2), carbon monoxide (CO), and indoor formaldehyde (HCHO). Mean reductions in indoor/outdoor (I/O) ratios across all systems after the intervention were approximately 12% (p = 0.001), 10% (p = 0.008), 42% (p < 0.001), 39% (p = 0.002), and 33% (p = 0.007), for CO2, NO2, and estimated PM1, PM2.5, and PM10, respectively. There was a reduction in I/O ratios for all measured constituents with each type of system, on average, but with varying magnitude and levels of statistical significance. The magnitudes of mean differences in I/O pollutant concentrations ratios were generally largest for most pollutants in the homes that received continuous balanced with ERV and smallest in the homes that received intermittent CFIS systems, with apparent benefits to providing ventilation continuously rather than intermittently. All ventilation system types maintained similar indoor temperatures during pre- and post-intervention periods.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Chicago , Estudos Cross-Over , Humanos , Respiração Artificial
8.
Dis Markers ; 2021: 6591784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34992694

RESUMO

METHODS AND RESULTS: We conducted a retrospective study of 531 patients with ultrasonogram-confirmed NAFLD who underwent percutaneous coronary intervention (PCI). Then, all patients were separated into four categories by Gensini score (0, 0-9, 9-48, and ≥48) for use in ordinal logistic regression analysis to determine whether NAFLD fibrosis was associated with increased Gensini scores. Mediation analysis was used to investigate whether systemic inflammation is a mediating factor in the association between NAFLD fibrosis and CAD severity. FIB - 4 > 2.67 (OR = 5.67, 95% CI 2.59-12.38) and APRI > 1.5 (OR = 14.8, 95% CI 3.24-67.60) remained to be independent risk factors for the severity of CAD after adjusting for conventional risk factors, whereas among the inflammation markers, only neutrophils and neutrophil-to-lymphocyte ratio (NLR) were independently associated with CAD. Multivariable ordinal regression analysis suggested that increasing Gensini score (0, 0-9, 9-48, and ≥48) was associated with advanced NAFLD fibrosis. ROC curve showed that either fibrosis markers or inflammation markers, integrating with traditional risk factors, could increase the predictive capacity for determining CAD. Inflammation markers, especially neutrophils and NLR, were mediators of the relationship between NAFLD fibrosis and CAD severity. CONCLUSIONS: NAFLD patients with advanced fibrosis are at a high risk of severe coronary artery stenosis, and inflammation might mediate the association between NAFLD fibrosis and CAD severity.


Assuntos
Doença da Artéria Coronariana/complicações , Inflamação/complicações , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Idoso , Doença da Artéria Coronariana/sangue , Feminino , Humanos , Inflamação/sangue , Cirrose Hepática/sangue , Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Hepatopatia Gordurosa não Alcoólica/sangue , Estudos Retrospectivos , Índice de Gravidade de Doença
9.
BMC Palliat Care ; 19(1): 185, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33287827

RESUMO

BACKGROUND: Patients suffering from gastrointestinal cancer comprise a large group receiving home hospice care in China, however, little is known about the prediction of their survival time. This study aimed to develop a gastrointestinal cancer-specific non-lab nomogram predicting survival time in home-based hospice. METHODS: We retrospectively studied the patients with gastrointestinal cancer from a home-based hospice between 2008 and 2018. General baseline characteristics, disease-related characteristics, and related assessment scale scores were collected from the case records. The data were randomly split into a training set (75%) for developing a predictive nomogram and a testing set (25%) for validation. A non-lab nomogram predicting the 30-day and 60-day survival probability was created using the least absolute shrinkage and selection operator (LASSO) Cox regression. We evaluated the performance of our predictive model by means of the area under receiver operating characteristic curve (AUC) and calibration curve. RESULTS: A total of 1618 patients were included and divided into two sets: 1214 patients (110 censored) as training dataset and 404 patients (33 censored) as testing dataset. The median survival time for overall included patients was 35 days (IQR, 17-66). The 5 most significant prognostic variables were identified to construct the nomogram among all 28 initial variables, including Karnofsky Performance Status (KPS), abdominal distention, edema, quality of life (QOL), and duration of pain. In training dataset validation, the AUC at 30 days and 60 days were 0.723 (95% CI, 0.694-0.753) and 0.733 (95% CI, 0.702-0.763), respectively. Similarly, the AUC value was 0.724 (0.673-0.774) at 30 days and 0.725 (0.672-0.778) at 60 days in the testing dataset validation. Further, the calibration curves revealed good agreement between the nomogram predictions and actual observations in both the training and testing dataset. CONCLUSION: This non-lab nomogram may be a useful clinical tool. It needs prospective multicenter validation as well as testing with Chinese clinicians in charge of hospice patients with gastrointestinal cancer to assess acceptability and usability.


Assuntos
Neoplasias Gastrointestinais/classificação , Neoplasias Gastrointestinais/mortalidade , Nomogramas , Prognóstico , Adulto , Idoso , Área Sob a Curva , China , Feminino , Neoplasias Gastrointestinais/fisiopatologia , Hospitais para Doentes Terminais/organização & administração , Hospitais para Doentes Terminais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
10.
Clin Chim Acta ; 510: 62-72, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32622968

RESUMO

Pyroptosis is a pro-inflammatory type of regulated cell death (RCD) characterized by gasdermin D (GSDMD)-mediated membrane pore formation, cell swelling and rapid lysis, followed by the massive release of pro-inflammatory mediators such as interleukin-1ß and interleukin-18. There are two main pathways of pyroptosis: the caspase-1-mediated canonical pathway and the caspase-4/5/11-mediated noncanonical pathway. However, the caspase-3-gasdermin E (GSDME) pathway and caspase-8-GSDMD pathway also induce pyroptosis. Pyroptosis can not only cause local inflammation but also lead to amplification of the inflammatory response. Recent studies have suggested that pyroptosis is closely related with cardiovascular disease (CVD); for example, in atherosclerosis, myocardial infarction, ischemia-reperfusion injury, heart failure, coronary calcification and aortic aneurysm, study results have promoted the development of inhibitors targeting the components related to pyroptosis, and some agents have been clinically proven to have cardiovascular benefits. In this review, we summarize emerging evidence to discuss the progressive understanding of pyroptosis and the pathways, effect and effectors of pyroptosis, as well as the role of pyroptosis in CVD. Additionally, we summarize pyroptosis-related pathway inhibitors and classic cardiovascular drugs targeting pyroptosis.


Assuntos
Doenças Cardiovasculares , Traumatismo por Reperfusão , Caspase 1 , Humanos , Inflamação , Piroptose
11.
J Gastroenterol Hepatol ; 35(12): 2051-2065, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32579269

RESUMO

BACKGROUND AND AIM: This meta-analysis aims to explore the risk of colorectal polyps among non-alcoholic fatty liver disease (NAFLD) patients. METHODS: We searched PubMed, EMBASE, and Cochrane library databases using predefined search term to identify eligible studies (published up to 7 November 2019). Data from selected studies were extracted by using a standardized information collection form, and meta-analyses were performed using random-effects model. The statistical heterogeneity among studies (I2 ), subgroup analyses, meta-regression analyses, and the possibility of publication bias were assessed. RESULTS: Twenty observational (12 cross-sectional, two case-control, and six cohort) studies met the eligibility criteria, involving 142 387 asymptomatic adults. In cross-sectional/case-control studies, NAFLD was found to be associated with an increased risk of colorectal polyps (odds ratio [OR] = 1.34; 95% confidence interval [CI] = 1.23-1.47) (including unclassified colorectal polyps, hyperplastic polyps, adenomas, and cancers) with statistically significant heterogeneity (I2  = 67.8%; P < 0.001). NAFLD was also associated with a higher risk of incident colorectal polyps (hazard ratio = 1.60; 95% CI = 1.36-1.87) with low heterogeneity (I2  = 21.8%; P = 0.263) in longitudinal studies. The severity of NAFLD was associated with a higher risk of colorectal adenomas (OR = 1.57; 95% CI = 1.30-1.88), but not colorectal cancer (OR = 1.37; 95% CI = 0.92-2.03). The subgroup analysis according to gender showed that NAFLD was significantly associated with a higher risk of colorectal polyps in the male population without significant heterogeneity (OR = 1.47; 95% CI = 1.29-1.67, I2  = 0%), but not in the female population (OR = 0.88; 95% CI = 0.60-1.29, I2  = 34.2%). CONCLUSIONS: NAFLD was associated with an increased risk of colorectal polyps. There was a significant difference of the relationship between genders, which suggested more precise screening colonoscopy recommendation in NAFLD patients according to gender.


Assuntos
Colo , Pólipos Intestinais/epidemiologia , Pólipos Intestinais/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Reto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Risco , Fatores Sexuais
12.
Polymers (Basel) ; 12(2)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059358

RESUMO

Silver (Ag) nanoparticles were synthesized by a facile route in the presence of oleic acid and n-propylamine. It was shown that the average primary size of the as-synthesized Ag nanoparticles was approximately 10 nm and the surface of as-synthesized Ag nanoparticles was capped with monolayer surfactants with the content of 19.6%. Based on as-synthesized Ag nanoparticles, polyoxymethylene (POM)/Ag nanocomposites were prepared. The influence of Ag nanoparticles on non-isothermal crystallization behavior of POM was investigated by differential scanning calorimetry (DSC). The Jeziorny, Jeziorny-modified Avrami, Ozawa, Liu and Mo, Ziabicki and Kissinger models were applied to analyze the non-isothermal melt crystallization data of POM/Ag nanocomposites. Results of half time (t1/2), crystallization rate parameter (CRP), crystallization rate function (K(T)), kinetic parameter (F(T)), the kinetic crystallizability at unit cooling rate (GZ) and the crystallization activation energy (∆E) were determined. Small amounts of Ag nanoparticles dispersed into POM matrix were shown to act as heterogeneous nuclei, which could enhance the crystallization rate of POM, increase the number of POM spherulites and reduce POM spherulites size. However, the higher loading of Ag nanoparticles were easily aggregated, which restrained POM crystallization to some degree. Furthermore, the POM/Ag nanocomposites showed robust antibacterial activity against Escherichia coli and Staphylococcus aureus.

13.
Indoor Air ; 29(4): 656-669, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31077624

RESUMO

Particle air filters used in central residential forced-air systems are most commonly evaluated for their size-resolved removal efficiency for particles 0.3-10 µm using laboratory tests. Little information exists on the removal efficiency of commercially available residential filters for particles smaller than 0.3 µm or for integral measures of mass-based aerosol concentrations (eg, PM2.5 ) or total number concentrations (eg, ultrafine particles, or UFPs) that are commonly used in regulatory monitoring and building measurements. Here, we measure the size-resolved removal efficiency of 50 new commercially available residential HVAC filters installed in a recirculating central air-handling unit in an unoccupied apartment unit using alternating upstream/downstream measurements with incense and NaCl as particle sources. Size-resolved removal efficiencies are then used to estimate integral measures of PM2.5 and total UFP removal efficiency for the filters assuming they are challenged by 201 residential indoor particle size distributions (PSDs) gathered from the literature. Total UFP and PM2.5 removal efficiencies generally increased with manufacturer-reported filter ratings and with filter thickness, albeit with numerous exceptions. PM2.5 removal efficiencies were more influenced by the assumption for indoor PSD than total UFP removal efficiencies. Filters with the same ratings but from different manufacturers often had different removal efficiencies for PM2.5 and total UFPs.


Assuntos
Filtros de Ar/normas , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Material Particulado/análise , Ar Condicionado , Monitoramento Ambiental , Calefação , Habitação , Humanos , Tamanho da Partícula , Ventilação
14.
Chaos ; 28(1): 013113, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29390621

RESUMO

By using a simple state feedback controller in a three-dimensional chaotic system, a novel 4D chaotic system is derived in this paper. The system state equations are composed of nine terms including only one constant term. Depending on the different values of the constant term, this new proposed system has a line of equilibrium points or no equilibrium points. Compared with other similar chaotic systems, the newly presented system owns more abundant and complicated dynamic properties. What interests us is the observation that if the value of the constant term of the system is nonzero, it has no equilibria, and therefore, the Shil'nikov theorem is not suitable to verify the existence of chaos for the lack of heteroclinic or homoclinic trajectory. However, one-wing, two-wing, three-wing, and four-wing hidden attractors can be obtained from this new system. In addition, various coexisting hidden attractors are obtained and the complex transient transition behaviors are also observed. More interestingly, the unusual and striking dynamic behavior of the coexistence of infinitely many hidden attractors is revealed by selecting the different initial values of the system, which means that extreme multistability arises. The rich and complex hidden dynamic characteristics of this system are investigated by phase portraits, bifurcation diagrams, Lyapunov exponents, and so on. Finally, the new system is implemented by an electronic circuit. A very good agreement is observed between the experimental results and the numerical simulations of the same system on the Matlab platform.

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