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1.
J Magn Reson Imaging ; 59(2): 613-625, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37199241

RESUMO

BACKGROUND: Radiomics has been applied for assessing lymphovascular invasion (LVI) in patients with breast cancer. However, associations between features from peritumoral regions and the LVI status were not investigated. PURPOSE: To investigate the value of intra- and peritumoral radiomics for assessing LVI, and to develop a nomogram to assist in making treatment decisions. STUDY TYPE: Retrospective. POPULATION: Three hundred and sixteen patients were enrolled from two centers and divided into training (N = 165), internal validation (N = 83), and external validation (N = 68) cohorts. FIELD STRENGTH/SEQUENCE: 1.5 T and 3.0 T/dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI). ASSESSMENT: Radiomics features were extracted and selected based on intra- and peritumoral breast regions in two magnetic resonance imaging (MRI) sequences to create the multiparametric MRI combined radiomics signature (RS-DCE plus DWI). The clinical model was built with MRI-axillary lymph nodes (MRI ALN), MRI-reported peritumoral edema (MPE), and apparent diffusion coefficient (ADC). The nomogram was constructed with RS-DCE plus DWI, MRI ALN, MPE, and ADC. STATISTICAL TESTS: Intra- and interclass correlation coefficient analysis, Mann-Whitney U test, and least absolute shrinkage and selection operator regression were used for feature selection. Receiver operating characteristic and decision curve analyses were applied to compare performance of the RS-DCE plus DWI, clinical model, and nomogram. RESULTS: A total of 10 features were found to be associated with LVI, 3 from intra- and 7 from peritumoral areas. The nomogram showed good performance in the training (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.884 vs. 0.695 vs. 0.870), internal validation (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.813 vs. 0.695 vs. 0.794), and external validation (AUCs, nomogram vs. clinical model vs. RS-DCE plus DWI, 0.862 vs. 0.601 vs. 0.849) cohorts. DATA CONCLUSION: The constructed preoperative nomogram might effectively assess LVI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Radiômica , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética , Mama , Imageamento por Ressonância Magnética
2.
Cancer Commun (Lond) ; 42(12): 1387-1402, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36274263

RESUMO

BACKGROUND: Patients with refractory or relapsed acute myeloid leukemia (AML) have poor survival, necessitating the exploration of optimized therapeutic strategy. Here, we aimed to investigate clinical outcomes and health-related quality of life (HR-QoL) after total therapy, which included allogeneic hematopoietic stem cell transplantation (allo-HSCT), and prophylactic donor lymphocyte infusion (DLI) in the early phase after transplantation, followed by multiple measurable residual disease (MRD) and graft-versus-host disease (GvHD)-guided DLIs. METHODS: Consecutive patients who had refractory or relapsed AML and had received non-T-cell-depleted allo-HSCT at Peking University Institute of Hematology were included in the study. If the patients achieved complete remission at 30 days after transplantation and had no evidence of relapse, severe infection, organ failure, and active GvHD at the time of planned DLI, prophylactic DLI was administered at 30 days after transplantation for human leukocyte antigen (HLA)-matched related HSCT or at 45-60 days after transplantation for haploidentical or unrelated HSCT. Subsequently, multiple DLIs were administered based on MRD results and whether they developed GvHD after transplantation. RESULTS: A total of 105 patients were eligible. Eighty-seven patients received prophylactic DLI (group B), while 18 did not receive prophylactic DLI (group A). Among 105 patients, the cumulative incidence of grade 2-4 acute GvHD and chronic GvHD was 40.6% (95% confidence interval [CI] = 30.6%-50.6%) and 73.3% (95% CI = 67.4%-79.2%), respectively. The cumulative incidence of relapse (CIR), transplant-related mortality (TRM), and leukemia-free survival (LFS) at 5 years after transplantation were 31.5% (95% CI = 21.9%-41.1%), 22.1% (95% CI = 11.3%-32.9%), and 46.4% (95% CI = 36.8%-56.0%), respectively. In group B, the CIR, TRM, and LFS at 5 years after transplantation were 27.6% (95% CI = 17.6%-37.6%), 21.6% (95% CI = 11.2%-32.0%), and 50.8% (95% CI = 40.0%-61.6%), respectively. At the end of follow-up, 48 patients survived, and more than 90% of survivors had satisfactory recoveries of HR-QoL. CONCLUSIONS: Our study indicated that total therapy is not only associated with decreased CIR, comparable TRM, and better long-term LFS, but also with satisfactory HR-QoL for refractory or relapsed AML, compared with those of standard of care therapy reported previously. Therefore, total therapy may be an optimized therapeutic strategy for refractory or relapsed AML.


Assuntos
Doença Enxerto-Hospedeiro , Leucemia Mieloide Aguda , Humanos , Transplante Homólogo , Qualidade de Vida , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Leucemia Mieloide Aguda/terapia , Neoplasia Residual , Recidiva
3.
Front Psychol ; 12: 792950, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899547

RESUMO

The COVID-19 pandemic has caused a huge impact on global service sector. In the pandemic background, to understand the disparity in service sector outputs at the global level is crucial for assessing the effectiveness of development policies in different countries. This study investigate the global service sector and it aims to investigate the transitional dynamics of the output from the service sector by adopting stochastic kernel analyses. Distribution dynamics analyses are carried out for all the countries in the world. The data are then divided into different regional and income groups to evaluate the impacts of geographical location and income on the development of the service sector. The results show that the Global North will continue to make greater strides, while the output capacity in many Global South countries struggles to reach the global average. Moreover, it is shown that countries with higher per capita income will perform better in the development of their service sector than those with low per capita income, thereby highlighting the persistence of global inequality. Finally, this study shows that the Sub-Saharan Africa region and the South Asia region both are very important in the alleviation of global inequality.

4.
Front Public Health ; 9: 792947, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888291

RESUMO

The spread of COVID-19 has significantly dampened global economic activity and has also wreaked havoc on the industrial sector. Understanding the disparity and convergence of global industrial outputs is important in assessing the effectiveness of concurrent development policies. This study investigates the spatial distribution of global industrial output to unveil the disparity in industrial development and the feasibility of achieving convergence over time. Stochastic kernel analyses are carried out for national regimes to study the overall pattern of industrialization for all the countries in the world. Countries are then classified into different groups to further analyse the geographical and income effects on industrial development. The results show that disparity between the Global North and the Global South will enlarge further in the future. Industrial development in the Global North will continue to prosper, while the industrial output in many countries in the Global South just cannot reach the global average.


Assuntos
COVID-19 , Geografia , Humanos , Desenvolvimento Industrial , Indústrias , SARS-CoV-2
5.
Huan Jing Ke Xue ; 42(11): 5210-5219, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708960

RESUMO

Real-time BTEX(including benzene, toluene, ethylbenzene, m-, p-, and o-xylenes) were measured continuously in Tianjin urban site in July 2019 and January 2020 using a Syntech Spectras GC955 analyzer. The BTEX concentration levels, composition, and evolutionary mechanisms during typical pollution episodes were investigated. The potential sources of BTEX were analyzed qualitatively using the diagnostic ratios method. Finally, the BTEX health risk was evaluated by using the human exposure analysis and evaluation method according to US EPA. The averaged total mixing ratio of BTEX were 1.32×10-9 and 4.83×10-9 during ozone pollution and haze episodes, respectively. Benzene was the most abundant species, followed by toluene. The mixing ratio of BTEX was largely affected by short southwestern distance transportation in January, while local emissions in July. In addition, the BTEX mixing ratio depended on the influence of temperature and relative humidity(RH) in July, while the concentration was more sensitive to changes in RH when the temperature was low in January. Diagnostic ratios and source implications suggested that the BTEX was affected mainly by biomass/biofuel/coal burning during haze episodes. The traffic related emissions also had an impact except for the influence of biomass/biofuel/coal burning in July. The averaged hazard quotient(HQ) values were 0.072 and 0.29 during ozone pollution and haze episodes, respectively, which were in the upper safety range limit recommended by the US EPA. The carcinogenic risk posed by benzene in both cleaning and pollution processes was higher than the safety threshold set by the US EPA, which should be monitored carefully.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Benzeno/análise , Benzeno/toxicidade , Derivados de Benzeno/análise , Derivados de Benzeno/toxicidade , Monitoramento Ambiental , Humanos , Medição de Risco , Tolueno/análise , Tolueno/toxicidade , Xilenos
6.
Artif Intell Med ; 84: 64-78, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29129481

RESUMO

BACKGROUND AND OBJECTIVE: Current retinal prostheses can only generate low-resolution visual percepts constituted of limited phosphenes which are elicited by an electrode array and with uncontrollable color and restricted grayscale. Under this visual perception, prosthetic recipients can just complete some simple visual tasks, but more complex tasks like face identification/object recognition are extremely difficult. Therefore, it is necessary to investigate and apply image processing strategies for optimizing the visual perception of the recipients. This study focuses on recognition of the object of interest employing simulated prosthetic vision. METHOD: We used a saliency segmentation method based on a biologically plausible graph-based visual saliency model and a grabCut-based self-adaptive-iterative optimization framework to automatically extract foreground objects. Based on this, two image processing strategies, Addition of Separate Pixelization and Background Pixel Shrink, were further utilized to enhance the extracted foreground objects. RESULTS: i) The results showed by verification of psychophysical experiments that under simulated prosthetic vision, both strategies had marked advantages over Direct Pixelization in terms of recognition accuracy and efficiency. ii) We also found that recognition performance under two strategies was tied to the segmentation results and was affected positively by the paired-interrelated objects in the scene. CONCLUSION: The use of the saliency segmentation method and image processing strategies can automatically extract and enhance foreground objects, and significantly improve object recognition performance towards recipients implanted a high-density implant.


Assuntos
Inteligência Artificial , Processamento de Imagem Assistida por Computador/métodos , Visão Ocular , Percepção Visual , Próteses Visuais , Pessoas com Deficiência Visual/reabilitação , Adulto , Movimentos Oculares , Reconhecimento Facial , Feminino , Humanos , Masculino , Cadeias de Markov , Fosfenos , Desenho de Prótese , Reconhecimento Psicológico , Pessoas com Deficiência Visual/psicologia , Adulto Jovem
7.
Bioresour Technol ; 208: 13-18, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26913643

RESUMO

Anaerobic digestion (AD) represents a potential way to achieve energy recovery from waste organics. In this study, a novel bioelectrochemically-assisted anaerobic reactor is assembled by two AD systems separated by anion exchange membrane, with the cathode placing in the inside cylinder (cathodic AD) and the anode on the outside cylinder (anodic AD). In cathodic AD, average methane production rate goes up to 0.070 mL CH4/mL reactor/day, which is 2.59 times higher than AD control reactor (0.027 m(3) CH4/m(3)/d). And COD removal is increased ∼15% over AD control. When changing to sludge fermentation liquid, methane production rate has been further increased to 0.247 mL CH4/mL reactor/day (increased by 51.53% comparing with AD control). Energy recovery efficiency presents profitable gains, and economic revenue from increased methane totally self-cover the cost of input electricity. The study indicates that cathodic AD could cost-effectively enhance methane production rate and degradation of glucose and fermentative liquid.


Assuntos
Reatores Biológicos , Eletrólise , Metano/metabolismo , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/economia , Eletrodos , Desenho de Equipamento , Fermentação , Glucose/metabolismo , Esgotos , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/instrumentação
8.
Nucl Med Commun ; 37(1): 92-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26513054

RESUMO

OBJECTIVE: To investigate the value of N-NH3·H2O PET/computed tomography (CT) and the inhibitor, acetazolamide (ACZ), in the quantitative diagnosis of early liver fibrosis and the assessment of liver fibrosis stage. MATERIALS AND METHODS: Twenty-four male Wistar rats (293.54±37.99 g) were used in this study and grouped by pathology after biopsy. Using N-NH3·H2O as an imaging agent and ACZ as an aquaporin 1 inhibitor, the rats were subjected to a dynamic PET/CT scan for 45 min. According to data reconstruction and imaging analysis, we calculated the mean standard uptake value (SUVmean) of the liver at the time points of 20, 90 s, 5, 10, 15, 20, and 25 min. From the results of N-NH3·H2O, the liver SUVmean in the control group and the liver fibrosis model group at different time points were compared. In addition, blood perfusion, interstitial diffusion, and N-NH3·H2O metabolism of the two groups were compared. Single-factor analysis of variance was used to analyze the differences between the SUVs in the groups at any time point and the paired-sample t-test was used to compare the SUVs before and after addition of the inhibitor. RESULTS: We included four rats in the control group (S0) and 20 rats in the liver fibrosis group (which included early-stage S1: 11 rats, progressive-stage S2+S3+S4: nine rats). Three rats in S0, seven rats in S1, and six rats in S2+S3+S4 were paired. The SUVmean at 90 s was statistically different (P<0.05); however, the other groups showed statistical difference at all time points (P>0.05). After the addition of the inhibitor, ACZ, the SUVmean of S0 and S2+S3+S4 at 10, 15, 20, and 25 min was statistically different (P<0.05). CONCLUSION: N-NH3·H2O PET/CT may aid the diagnosis of liver fibrosis. N-NH3·H2O PET/CT combined with ACZ may help distinguish between the early stage and the progressive stage of liver fibrosis.


Assuntos
Amônia/química , Cirrose Hepática/diagnóstico por imagem , Radioisótopos de Nitrogênio , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Água/química , Animais , Aquaporina 1/metabolismo , Diagnóstico Precoce , Regulação da Expressão Gênica , Fígado/diagnóstico por imagem , Fígado/metabolismo , Masculino , Imagem Multimodal , Ratos , Ratos Wistar
9.
ACS Appl Mater Interfaces ; 8(1): 696-702, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26651152

RESUMO

One main difficulty for the technological development of photoelectrochemical (PEC) water splitting (WS) devices is the fabrication of active, stable and cost-effective photoelectrodes that ensure high performance. Here, we report the development of a CuO/Silicon based photoanode, which shows an onset potential for the water oxidation of 0.53 V vs SCE at pH 9, that is, an overpotential of 75 mV, and high stability above 10 h. These values account for a photovoltage of 420 mV due to the absorbed photons by silicon, as proven by comparing with analogous CuO/FTO electrodes that are not photoactive. The photoanodes have been fabricated by sputtering a thin film of Cu(0) on commercially available n-type Si wafers, followed by a photoelectrochemical treatment in basic pH conditions. The resulting CuO/Cu layer acts as (1) protective layer to avoid the corrosion of nSi, (2) p-type hole conducting layer for efficient charge separation and transportation, and (3) electrocatalyst to reduce the overpotential of the water oxidation reaction. The low cost, low toxicity, and good performance of CuO-based coatings can be an attractive solution to functionalize unstable materials for solar energy conversion.

10.
J Colloid Interface Sci ; 354(1): 15-22, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21040929

RESUMO

A low-cost, green, and reproducibly non-injection one-pot synthesis of high-quality CdS quantum dots (QDs) is reported. The synthesis was performed in the open air by mixing precursors cadmium stearate and S powder into a new solvent N-oleoylmorpholine. An overlapped nucleation-growth stage followed by a dominated growth stage was observed. The resulting QDs exhibited well-resolved absorption fine substructure and a dominant band-edge emission with a narrow size distribution (the full width at half maximum (fwhm) was only 22-24nm). The maximum photoluminescence (PL) quantum yield (QY) was as high as 46.5%. Highly monodispersed CdS QDs with tunable sizes and similar PL fwhm and QYs could also be obtained from the CdS QDs in a large-scale synthesis. The high-resolution transmission electron microscopy (HRTEM) images and powder X-ray diffraction (XRD) pattern suggested that the as-prepared QDs with high crystallinity had a cubic structure. A significant PL improvement and a continuous QY increase for the CdS QDs were observed during a long storage time in air and in a glovebox under room temperature. A slow surface reconstruction was proposed to be the cause for the PL enhancement of CdS QDs.


Assuntos
Compostos de Cádmio/síntese química , Pontos Quânticos , Sulfetos/síntese química , Compostos de Cádmio/química , Técnicas de Laboratório Clínico/economia , Luminescência , Sulfetos/química
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