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1.
Inorg Chem ; 62(36): 14815-14822, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37647605

RESUMO

Developing high-activity electrocatalysts is of great significance for the commercialization of direct alcohol fuel cells (DAFCs), but it still faces challenges. Herein, three-dimensional (3D) porous PdPtBiTe dumbbells (DBs) were successfully fabricated via the visible photoassisted method. The alloying effect, defect-rich surface/interface and nanoscale cavity, and open pores make the 3D PdPtBiTe DBs a comprehensive and remarkable electrocatalyst for the C1-C3 alcohol (ethanol, ethylene glycol, glycerol, and methanol) oxidation reaction (EOR, EGOR, GOR, and MOR, respectively) in an alkaline electrolyte, and the results of in situ Fourier transform infrared spectra revealed a superior C-C bond cleavage ability. The 3D PdPtBiTe DBs exhibit ultrahigh EOR, EGOR, GOR, and MOR mass activities of 25.4, 23.2, 16.8, and 18.3 A mgPd + Pt-1, respectively, considerably surpassing those of the commercial Pt/C and Pd/C. Moreover, the mass peak power densities of 3D PdPtBiTe DBs in actual ethanol, ethylene glycol, glycerol, or methanol fuel cells increase to 409.5, 501.5, 558.0, or 601.3 mW mgPd + Pt-1 in O2, respectively. This study provides a new class of multimetallic nanomaterials as state-of-the-art multifunctional anode electrocatalysts for actual DAFCs.

2.
Adv Mater ; 35(40): e2303672, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37378656

RESUMO

Ultrathin 2D nanomaterials have attracted extensive attention due to their fascinating applications in sustainable and clean-energy-related devices, but obtaining ultrathin 2D multimetallic polycrystalline structures with large lateral dimensions remains a challenge. In this study, ultrathin 2D porous PtAgBiTe and PtBiTe polycrystalline nanosheets (PNSs) are obtained via a visible-light-photoinduced Bi2 Te3 -nanosheet-mediated route. The PtAgBiTe PNSs are assembled by sub-5 nm grains with widths beyond 700 nm. Strain and ligand effects originating from the porous, curly polycrystalline structure endow the PtAgBiTe PNSs with robust hydrazine hydrate oxidation reaction activity. Theoretical research demonstrates that the modified Pt activates the N-H bonds in N2 H4 during the reaction, and strong hybridization between Pt-5d and N-2p facilitates dehydrogenation while reducing energy consumption. The peak power densities of the PtAgBiTe PNSs in actual hydrazine-O2 /air fuel cell devices are boosted to 532.9/315.9 mW cm-2 , while those of the commercial Pt/C are 394.7/157.9 mW cm-2 . This work provides a strategy not only for preparing ultrathin multimetallic PNSs but also for finding promising electrocatalysts for actual hydrazine fuel cells.

3.
Adv Mater ; 33(42): e2103383, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34468056

RESUMO

Ultrathin 2D metal nanostructures have sparked a lot of research interest because of their improved electrocatalytic properties for fuel cells. So far, no effective technique for preparing ultrathin 2D Pd-based metal nanostructures with more than three compositions has been published. Herein, a new visible-light-induced template technique for producing PdAuBiTe alloyed 2D ultrathin nanosheets is developed. The mass activity of the PdAuBiTe nanosheets against the oxygen reduction reaction (ORR) is 2.48 A mgPd -1 , which is 27.5/17.7 times that of industrial Pd/C/Pt/C, respectively. After 10 000 potential cyclings, there is no decrease in ORR activity. The PdAuBiTe nanosheets exhibit high methanol tolerance and in situ anti-CO poisoning properties. The PdAuBiTe nanosheets, as cathode electrocatalysts in direct methanol fuel cells, can thus give significant improvement in terms of power density and durability. In O2 /air, the power density can be increased to 235.7/173.5 mW cm-2 , higher than that reported in previous work, and which is 2.32/3.59 times higher than Pt/C.

4.
Mol Plant ; 14(4): 556-570, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33429094

RESUMO

Many important crops (e.g., tuber, root, and tree crops) are cross-pollinating. For these crops, no inbred lines are available for genetic study and breeding because they are self-incompatible, clonally propagated, or have a long generation time, making the identification of agronomically important genes difficult, particularly in crops with a complex autopolyploid genome. In this study, we developed a method, OutcrossSeq, for mapping agronomically important loci in outcrossing crops based on whole-genome low-coverage resequencing of a large genetic population, and designed three computation algorithms in OutcrossSeq for different types of outcrossing populations. We applied OutcrossSeq to a tuberous root crop (sweet potato, autopolyploid), a tree crop (walnut tree, highly heterozygous diploid), and hybrid crops (double-cross populations) to generate high-density genotype maps for the outcrossing populations, which enable precise identification of genomic loci underlying important agronomic traits. Candidate causative genes at these loci were detected based on functional clues. Taken together, our results indicate that OutcrossSeq is a robust and powerful method for identifying agronomically important genes in heterozygous species, including polyploids, in a cost-efficient way. The OutcrossSeq software and its instruction manual are available for downloading at www.xhhuanglab.cn/tool/OutcrossSeq.html.


Assuntos
Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Locos de Características Quantitativas/genética , Mapeamento Cromossômico , Genoma de Planta/genética , Genótipo , Melhoramento Vegetal , Poliploidia
5.
Artigo em Inglês | MEDLINE | ID: mdl-32265037

RESUMO

Cardiac catheterization procedures are performed on about 20,000 children with congenital heart disease (CHD) annually in China. The procedure, which involves exposure to ionizing radiation, causes DNA damage and may lead to increased cancer risk. We have studied chromosomal aberrations (CA) in peripheral lymphocytes of CHD children. CA frequencies were assessed in an interventional group of 70 children who underwent cardiac catheterization and a control group of 51 children receiving open-heart surgery. Total CA and all chromosome-type aberrations were higher in the exposed children than in the control group. With respect to the type of septal defect, the translocation frequency was higher in patients with ventricular rather than atrial defects. Cardiac catheterization procedures increase CA frequencies and may also increase the risk of cancer.


Assuntos
Cateterismo Cardíaco/efeitos adversos , Aberrações Cromossômicas/efeitos da radiação , Cardiopatias Congênitas/cirurgia , Linfócitos/efeitos da radiação , Radiação Ionizante , Adolescente , Cateterismo Cardíaco/métodos , Estudos de Casos e Controles , Criança , Pré-Escolar , China , Feminino , Cardiopatias Congênitas/patologia , Humanos , Linfócitos/imunologia , Masculino , Duração da Cirurgia , Cultura Primária de Células , Risco
6.
J Colloid Interface Sci ; 562: 244-251, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31838360

RESUMO

In response to the scarcity of precious metals, the development of precious-metal-saving electrocatalysts exhibiting high mass activity (MA) and durability towards oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) for both proton-exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs) has aroused increasing attention. In this study, octahedral Cu-rich PtCu alloy is seeded to fabricate near-surface composition-tunable PtCu hollow octahedral nanoparticles (HONs) with the wall thickness of ~2.1 nm. Due to both the alloying effects of near surface and the special hollow octahedral structure, the PtCu/C HONs exhibit significantly higher MA and durability than commercial Pt/C towards both ORR in alkaline medium and MOR in sulfuric acid electrolyte. The ORR MA of Pt44.1Cu55.9/C HONs are up to 2.60 A mgPt-1 that is 18.5-fold enhancement compared with that of Pt/C. Besides, after 10,000 voltage cycles, the MA of Pt44.1Cu55.9/C HONs remains to be 1.61 A mgPt-1, a datum 53.7 times that of Pt/C. The in situ CO polarization curves exhibit that the Pt44.1Cu55.9 HONs/C own high resistance to CO poisoning. For MOR in sulfuric acid electrolyte, the optimum SA/MA of PtCu/C HONs is 5.33 mA cm-2/1.94 A mgPt-1, which is 10.25/5.87 times higher than that of Pt/C. This study provides effective bifunctional cathode and anode electrocatalysts for both PEMFCs and DMFCs.

7.
Nanoscale ; 11(41): 19448-19454, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31490478

RESUMO

Recently, engineering high performance Pd-based nanocatalysts for alkaline ethanol fuel cells has attracted wide attention. Here, we report a one-pot synthesis of low-palladium ternary palladium-copper-cobalt (PdCuCo) alloy nanowires (NWs) with a diameter of ∼4.0 nm to improve the mass activity (MA) of ethanol electrooxidation in alkaline medium. The MA (7.45 A mg-1) of the Pd31Cu61Co8 NWs is 8.5-fold and 12.4-fold that of commercial Pd black and Pd/C, respectively. The reaction mechanism of the EOR and the reasons for the activity enhancement on Pd31Cu61Co8 NWs are elucidated based on the results of in situ Fourier transform infrared spectroscopy and structure characterization. Besides the electronic effect and surface defect sites, the coexistence of surface Cu and Co that have high capacities to activate water to produce reactive oxygen species is another key factor. This study shows an example of how to design low-palladium ternary PdCuCo NWs as improved anode electrocatalysts for alkaline direct ethanol fuel cells with high mass activity.

8.
ACS Appl Mater Interfaces ; 11(35): 32282-32290, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31408312

RESUMO

Recently, the preparation of a high-performance one-dimensional alloy nanostructure for fuel cells has been given increasing attention due to its smart-structure merits and electronic effect triggered by alloying different kinds of metals at the nanoscale. In this study, unique ternary PtCuCo nanochains assembled with small polyhedra are first achieved and used as high-performance anode electrocatalysts toward methanol oxidation at elevated temperature (60 °C) that is closer to the operating temperature of direct methanol fuel cells than room temperature. The specific activity/mass activity of Pt45Cu35Co20 one-dimensional nanochains can reach up to 18.24 mA cm-2/4.19 A mg-1Pt that is 9.25/10.47 times that of commercial Pt black in sulfuric acid medium. After a 3600 s durability test, the remaining current density of Pt45Cu35Co20 one-dimensional nanochains is 73.3 times that of commercial Pt black. The structure characterizations show that the high density of surface active sites, d-band center of the Pt downshift, moderate strain effect, and synergetic effect are jointly responsible for the enhanced electrocatalytic performance of one-dimensional ternary PtCuCo nanochains.

9.
Int J Nurs Stud ; 97: 14-20, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31129444

RESUMO

BACKGROUND: Depressive symptoms are common in patients with cancer and more prevalent in Chinese patients. The Center for Epidemiologic Studies Depression Scale is one of the most widely used self-report scales to assess depressive symptoms in both community and hospitalized samples. A revised Center for Epidemiologic Studies Depression Scale has been created, but the evidence on psychometric properties is limited. OBJECTIVES: To develop the Chinese version of the scale, and to examine the cross-cultural validity, structural validity, construct validity, internal consistency, test-retest reliability, measurement error, responsiveness, and floor/ceiling effect of the scale among patients with cancer according to the recommendation in the consensus-based standards for the selection of health status measurement instruments checklist. DESIGN: A cross-sectional survey design with 33 participants (approximately 10%) completing the follow-up survey for evaluating the test-retest reliability. SETTINGS: Randomly selected eight wards of an oncology hospital in China. PARTICIPANTS: Of the 595 patients we approached in the randomly selected eight wards, 310 gave their informed consent and completed the survey. METHODS: The Chinese version of the Center for Epidemiologic Studies Depression Scale-Revised was developed by four researchers (two translators and two reviewers) who were proficient in both English and Chinese. Participants completed the scale and the depression module of the Patient Health Questionnaire. Principal components analyses, Spearman's correlation, the Mann-Whitney U test, Cronbach's alpha, and the intraclass correlation coefficient were used. RESULTS: The cross-culture validity was excellent based on the consensus-based standards for the selection of the health status measurement instruments checklist. A two-factor structure was determined: somatic symptoms and affective-cognitive symptoms. The sufficient construct validity was supported by that the score of the Center for Epidemiologic Studies Depression Scale-Revised was strongly correlated with the depression module of the Patient Health Questionnaire score (rho = 0.73, p < 0.001) and patients who had received chemotherapy (p = 0.002)/radiotherapy (p = 0.035) reported higher scores of depression than those who have not. The Cronbach's alphas of the total scale and subscales ranged from 0.82-0.88. The test-retest reliability was sufficient (intraclass correlation coefficient = 0.73-0.81, all p < 0.001) for total scale and subscales. The smallest detectable change was 2.98 and the responsiveness was adequate, with no floor/ceiling effect. CONCLUSIONS: This study supports the Chinese version of the Center for Epidemiologic Studies Depression Scale-Revised as a valid and reliable measurement of depressive symptoms in patients with cancer.


Assuntos
Depressão/diagnóstico , Neoplasias/complicações , Psicometria , Inquéritos e Questionários , China , Estudos Transversais , Depressão/etiologia , Humanos
10.
Dose Response ; 17(1): 1559325818820649, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30670937

RESUMO

In this study, the effect of ionizing radiation on 8-hydroxy-2'-deoxyguanosine (8-OHdG) in human peripheral blood was investigated. Blood samples were collected from 230 radiation workers and 8 patients who underwent radiotherapy for population study. Blood samples from 2 healthy individuals were irradiated with different X-ray doses for in vitro experiment, and levels of 8-OHdG in serum and cell culture supernatants were assessed by enzyme-linked immunosorbent assay. Observations demonstrated the positive relationships between serum 8-OHdG level and radiation dose and working period were observed, and serum 8-OHdG levels were higher among interventional radiation workers than among other hospital radiation workers. In addition, 8-OHdG yields in supernatants increased, peaked at 3 Gy of radiation dose, and then decreased with further increases in radiation; the dose-response curve obtained fitted a polynomial function. By contrast, a similar trend was not found in radiotherapy patients. The present study suggests that 8-OHdG may be a useful biomarker reflecting oxidative damage among workers occupationally exposed to low-dose radiation.

11.
Artigo em Chinês | MEDLINE | ID: mdl-25876970

RESUMO

OBJECTIVE: To measure peripheral serum levels of matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 19 (MMP19) in patients with pneumoconiosis, and to investigate their feasibility as potential biomarkers for pneumoconiosis. METHODS: Ninety-eight male patients with pneumoconiosis (49 patients in phase I, 36 patients in phase II, and 13 patients in phase III) were enrolled as subjects, which included 41 patients with silicosis and 57 patients with coal workers' pneumoconiosis. Ninety-eight healthy male physical examinees were used as controls. A fasting blood sample (3 ml) was collected from the peripheral venous blood of each patient or control, and the serum was separated from the blood sample. The expression levels of MMP9 and MMP19 in serum were measured by enzyme-linked immunosorbent assay. RESULTS: Serum levels of MMP9 and MMP19 in patients with silicosis or coal workers' pneumoconiosis were significantly lower than those in the control group (P < 0.05). Serum levels of MMP19 in patients with silicosis were significantly higher than those in patients with coal workers' pneumoconiosis (P < 0.05). Serum levels of MMP19 in patients exposed to dust for less than 7 years were significantly higher than those in patients exposed to dust for more than 20 years (P < 0.05). There were no significant differences in serum levels of MMP9 and MMP19 between patients with different levels of pulmonary function impairment (P > 0.05). Serum expression levels of MMP9 and MMP19 were positively correlated with each other in both patients with pneumoconiosis and those in the control group (P < 0.05). The serum expression level of MMP9 was negatively correlated with the stage of pneumoconiosis (P < 0.05). CONCLUSION: Serum MMP9 and MMP19 may be used as potential biomarkers for pneumoconiosis.


Assuntos
Biomarcadores , Metaloproteinase 9 da Matriz/sangue , Metaloproteinases da Matriz Secretadas/sangue , Pneumoconiose/sangue , Pneumoconiose/enzimologia , Antracose/enzimologia , Minas de Carvão , Poeira , Humanos , Pulmão , Masculino , Exposição Ocupacional , Silicose/enzimologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-25308435

RESUMO

The present study aims to measure chromosomal aberrations and micronuclei in peripheral blood lymphocytes from 25 subjects exposed to 0.10-0.33 Gy external or internal irradiation 32-41 years ago using conventional cytogenetic analysis methods. The frequencies of total chromosome-type aberrations and micronucleus significantly increased in the exposed group compared with that in age-matched control group (p<0.001); chromatid-type aberrations showed no difference between the two groups (p>0.05). When exposed subjects were divided into two groups based on exposure dose, higher levels of dicentric plus translocation frequencies were observed in the ≥0.15 Gy dose group compared with those in the <0.15 Gy dose group, though the difference was not significant. Borderline association between exposure dose and dicentric frequency was detected in the exposed group (r=0.358; p=0.079). These results suggest that the genotoxic effects of ionizing radiation remain in subjects exposed to low-dose radiation even decades after exposure.


Assuntos
Aberrações Cromossômicas , Linfócitos/patologia , Linfócitos/efeitos da radiação , Exposição Ocupacional/análise , Radiação Ionizante , Idoso , Estudos de Casos e Controles , Células Cultivadas , Aberrações Cromossômicas/efeitos da radiação , Aberrações Cromossômicas/estatística & dados numéricos , Análise Citogenética , Humanos , Masculino , Testes para Micronúcleos , Pessoa de Meia-Idade , Doses de Radiação , Fatores de Tempo
13.
Artigo em Chinês | MEDLINE | ID: mdl-23257093

RESUMO

OBJECTIVE: To measure the peripheral serum levels of CC-chemokine ligand-18 (CCL-18) in patients with pneumoconiosis, and to investigate the feasibility of the index asa potential biomarker for pneumoconiosis. METHODS: Seventy-seven male patients with pneumoconiosis (stage 1:40 cases, stage 2:22 cases, stage 3:15 cases), including 42 cases of silicosis and 35 cases of coal worker pneumoconiosis, were enrolled as subjects, and 162 healthy male physical examinees in our hospital were used as controls. A fasting blood sample (3 ml) was collected from the peripheral venous blood of each patient or control. The CCL-18 concentration in serum was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The serum CCL-18 concentrations of the patients with pneumoconiosis were significantly higher than those of the controls [(116.70 ± 82.85) ng/ml vs. (83.34 ± 64.83) ng/ml]; (Z = -2.389, P < 0.05). The serum CCL-18 concentrations of the patients with silicosis were significantly higher than those of the patients with coal worker pneumoconiosis (147.02 ± 93.32 ng/ml vs. 96.43 ± 47.19 ng/ml; Z = -3.030, P < 0.05). There were no significant differences in serum CCL-18 concentration among different stages of pneumoconiosis (P > 0.05). The degree of respiratory impairment was positively correlated with the serum CCL-18 concentration in patients with pneumoconiosis (r = 0.611, P < 0.01). CONCLUSION: Serum CCL-18 level can be used as a potential biomarker for pneumoconiosis.


Assuntos
Quimiocinas CC/sangue , Pneumoconiose/sangue , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Pneumoconiose/epidemiologia
16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 32(4): 293-5, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18973042

RESUMO

This paper introduces a display module which can be used on multi-mode medical images. The module has a small size and can be easily used for point-selecting puncture diagnosis and treatment, and registration for image fusion control points.


Assuntos
Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Design de Software , Tomografia Computadorizada por Raios X/métodos
18.
J Radiat Res ; 49(1): 63-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18187937

RESUMO

On 26 April 1999, three persons were accidentally exposed by high dose (60)Co irradiation. They suffered from severe (one case) or moderate (two cases) hemopoietic form of acute radiation sickness (ARS). As part of the comprehensive treatment, strict reverse isolation and granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy were applied. All the patients recovered after an appropriate treatment for 83 days. In our experience, the correct diagnosis and effective treatment at an early stage proved to be helpful to the patients in pulling out from the critical stage of acute radiation sickness. To avoid menstruation by the female patient just in the critical stage, we modified her menstruation cycle by testosterone. In our view, GM-CSF should be given as early as possible with enough dosage for promoting early hematological reconstruction. The experience obtained from the medical management of these patients is valuable for the treatment of such patients in the future.


Assuntos
Radioisótopos de Cobalto/efeitos adversos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Lesões por Radiação/tratamento farmacológico , Lesões por Radiação/etiologia , Liberação Nociva de Radioativos , Adulto , Criança , China , Feminino , Hematopoese/efeitos da radiação , Humanos , Contagem de Leucócitos , Masculino , Doses de Radiação , Indução de Remissão/métodos
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