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1.
Phys Rev Lett ; 126(25): 256402, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34241511

RESUMO

Here we use low-temperature scanning tunneling microscopy and spectroscopy to reveal the roles of the narrow electronic band in two 1T-TaS_{2}-related materials (bulk 1T-TaS_{2} and 4H_{b}-TaS_{2}). 4H_{b}-TaS_{2} is a superconducting compound with alternating 1T-TaS_{2} and 1H-TaS_{2} layers, where the 1H-TaS_{2} layer has a weak charge density wave (CDW) pattern and reduces the CDW coupling between the adjacent 1T-TaS_{2} layers. In the 1T-TaS_{2} layer of 4H_{b}-TaS_{2}, we observe a narrow electronic band located near the Fermi level, and its spatial distribution is consistent with the tight-binding calculations for two-dimensional 1T-TaS_{2} layers. The weak electronic hybridization between the 1T-TaS_{2} and 1H-TaS_{2} layers in 4H_{b}-TaS_{2} shifts the narrow electronic band to be slightly above the Fermi level, which suppresses the electronic correlation-induced band splitting. In contrast, in bulk 1T-TaS_{2}, there is an interlayer CDW coupling-induced insulating gap. In comparison with the spatial distributions of the electronic states in bulk 1T-TaS_{2} and 4H_{b}-TaS_{2}, the insulating gap in bulk 1T-TaS_{2} results from the formation of a bonding band and an antibonding band due to the overlap of the narrow electronic bands in the dimerized 1T-TaS_{2} layers.

2.
Phys Chem Chem Phys ; 21(14): 7288-7297, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30892328

RESUMO

Circularly polarized luminescence molecules with both thermally activated delayed fluorescence (TADF) and aggregation-induced emission (AIE) have been reported recently and are thought as potential candidates for circular polarized organic light-emitting diodes. Since the study of these kinds of systems is quite limited, it is of great importance to reveal the relationship between the geometry and the light-emitting mechanism. In this paper, the TADF and AIE mechanisms were studied based on the study of a series of binaphthalene-containing luminogenic enantiomers in both toluene and solid phases. It was found that there was no influence on the light-emitting properties of enantiomers except for the electronic circular dichroism (ECD). The radiative rates for both molecules were enhanced in the solid phase, while the non-radiative rates were significantly suppressed. Both factors can induce the AIE phenomenon. Based on the calculation of the decay rates and adiabatic excitation energy of the excited states, we found that the TADF mechanisms of the two molecules were different. One is realized by the up-conversion process between S1 and T1, while a two-step process is involved for the other. Our theoretical research successfully elucidates the experimental measurement and illustrates the AIE and TADF mechanism, which could provide valuable insights for the design of highly efficient CPL emitters.

3.
Nano Lett ; 17(6): 3471-3477, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28463560

RESUMO

Phase transitions in 2D materials can lead to massive changes in electronic properties that enable novel electronic devices. Tantalum disulfide (TaS2), specifically the "1T" phase (1T-TaS2), exhibits a phase transition based on the formation of commensurate charge density waves (CCDW) at 180 K. In this work, we investigate the impact of substrate choice on the phase transitions in ultrathin 1T-TaS2. Doping and charge transfer from the substrate has little impact on CDW phase transitions. On the contrary, we demonstrated that substrate surface roughness is a primary extrinsic factor in CCDW transition temperature and hysteresis, where higher roughness leads to smaller transition hysteresis. Such roughness can be simulated via surface texturing of SiO2/Si substrates, which controllably and reproducibly induces periodic strain in the 1T-TaS2 and thereby enables the potential for engineering CDW phase transitions.

4.
Transgenic Res ; 26(1): 1-11, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27995503

RESUMO

ß-Glucan is the predominant anti-nutritional factors in monogastric animal feed. Although ß-glucanase supplementation in diet can help to eliminate the adverse effects, enzyme stability is substantially modified during the feed manufacturing process. To determine whether the expression of endogenous ß-glucanase gene (GLU) in vivo can improve digestibility of dietary ß-glucan and absorption of nutrients, we successfully produced transgenic pigs via nuclear transfer which express the GLU from Paenibacillus polymyxa CP7 in the parotid gland. In three live transgenic founders, ß-glucanase activities in the saliva were 3.2, 0.07 and 0.03 U/mL, respectively, and interestingly the enzyme activities increased in the pigs from 178 days old to 789 days old. From the feed the amount of gross energy, crude protein and crude fat absorbed by the transgenic pigs was significantly higher than the non-transgenic pigs. Meanwhile the moisture content of the feces was significantly reduced in transgenic pigs compared with the non-transgenic pigs. Furthermore, in all positive G1 pigs, ß-glucanase activity was detectable and the highest enzyme activity reached 3.5 U/mL in saliva. Also, crude protein digestion was significantly higher in G1 transgenic pigs than in control pigs. Taken together, our data showed that the transgenic ß-glucanase exerted its biological catalytic function in vivo in the saliva, and the improved performance of the transgenic pigs could be accurately passed on to the offspring, indicating a promising alternative approach to improving nutrient availability was established to improve utilization of livestock feed through transgenic animals.


Assuntos
Animais Geneticamente Modificados/metabolismo , Suplementos Nutricionais , Glicosídeo Hidrolases/genética , Paenibacillus polymyxa/genética , Ração Animal , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Fezes/química , Glicosídeo Hidrolases/metabolismo , Paenibacillus polymyxa/enzimologia , Glândula Parótida/metabolismo , Suínos/genética , Suínos/crescimento & desenvolvimento
5.
Nano Lett ; 15(3): 1861-6, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25626012

RESUMO

In this work, we demonstrate abrupt, reversible switching of resistance in 1T-TaS2 using dc and pulsed sources, corresponding to an insulator-metal transition between the insulating Mott and equilibrium metallic states. This transition occurs at a constant critical resistivity of 7 mohm-cm regardless of temperature or bias conditions and the transition time is significantly smaller than abrupt transitions by avalanche breakdown in other small gap Mott insulating materials. Furthermore, this critical resistivity corresponds to a carrier density of 4.5 × 10(19) cm(-3), which compares well with the critical carrier density for the commensurate to nearly commensurate charge density wave transition. These results suggest that the transition is facilitated by a carrier driven collapse of the Mott gap in 1T-TaS2, which results in fast (3 ns) switching.

6.
Transgenic Res ; 24(3): 489-96, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25603989

RESUMO

The aflatoxin-detoxifizyme (ADTZ) gene derived from Armillariella tabescens was cloned into parotid gland-specific expression vector (pPSPBGPneo) to construct the parotid gland-specific vector expressing ADTZ (pPSPBGPneo-ADTZ). Transgenic mice were generated by microinjection and identified by using PCR and Southern blotting analysis. PCR and Southern blotting analysis showed that total six transgenic mice carried the ADTZ gene were generated. RT-PCR analysis indicated that the expression of ADTZ mRNA could be detected only in parotid glands of the transgenic mice. The ADTZ activity in the saliva was found to be 3.72 ± 1.64 U/mL. After feeding a diet containing aflatoxin B1 (AFB1) for 14 days, the effect of ADTZ on serum biochemical indexes and AFB1 residues in serum and liver of mice were evaluated. The results showed that total protein and globulin contents in the test treatment (transgenic mice) produced ADTZ were significantly higher than that of the positive control, while alanine aminotransferase and aspartate aminotransferase activity in serum of the test treatment (transgenic mice) were remarkably lower compared to that of the positive control (P < 0.05). Moreover, AFB1 residues in serum and liver of the test treatment (transgenic mice) were significantly lower compared with that of the positive control (P < 0.05). These results in the study confirmed that ADTZ produced in transgenic mice could reduce, even eliminate the negative effects of AFB1 on mice.


Assuntos
Inativação Metabólica/genética , Complexos Multienzimáticos/genética , Glândula Parótida/fisiologia , Aflatoxina B1/sangue , Aflatoxina B1/metabolismo , Aflatoxina B1/farmacocinética , Animais , Feminino , Fígado/metabolismo , Masculino , Camundongos Transgênicos , Complexos Multienzimáticos/metabolismo , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Saliva/fisiologia , Suínos/genética
7.
J Cardiovasc Pharmacol ; 65(5): 480-4, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25945865

RESUMO

OBJECTIVE: To observe the changes of serum heart-type fatty acid-binding protein (h-FABP) and brain natriuretic peptide (BNP) in children with chronic heart failure (CHF) and evaluate the effects of carvedilol. METHODS: A total of 36 patients with CHF, including 17 of endocardial fibroelastosis and 19 of dilated cardiomyopathy, were enrolled and were randomly divided into a carvedilol treatment group (group A) and a conventional treatment group (group B). Group A (n = 16) was treated with carvedilol and conventional treatment and group B (n = 20) was managed with conventional treatment only. Thirty healthy children were enrolled as controls. The concentrations of serum h-FABP and BNP were measured by enzyme-linked immunosorbent assay, and the left ventricular end-systolic diameter, left ventricular end-diastolic diameter, left ventricular ejection fraction (LVEF), left ventricular fractional shortening (LVFS), and cardiac index (CI) were measured by echocardiography. RESULTS: The concentrations of serum h-FABP and BNP in patients with CHF were significantly higher than in the control group (21.7 ± 4.3 ng/mL vs. 6.3 ± 1.7 ng/mL, 582.4 ± 180.6 pg/mL vs.31.2 ± 9.8 pg/mL, all P < 0.01), positively correlated with the degree of heart failure (all P < 0.01), and were both higher in groups endocardial fibroelastosis and dilated cardiomyopathy than in the control group (all P < 0.01), but there was no statistically significant difference between the 2 groups (P > 0.05). h-FABP concentration in patients with CHF was positively correlated with BNP (r = 0.78, P < 0.01) but negatively correlated with LVEF, LVFS, and CI (r = -0.65, -0.64, and -0.71, respectively; all P < 0.01). BNP concentration was also negatively correlated with LVEF, LVFS, and CI (r = -0.75, -0.61, and -0.79, respectively; all P<0.01). After treatment with carvedilol, the serum concentrations of h-FABP and BNP in group A were lower than in group B, and the magnitude of heart rate reduction, improvement of LVEF, LVFS, and CI, and reduction of left ventricular end-systolic diameter and left ventricular end-diastolic diameter in group A were all greater than in group B (all P < 0.01). Treatment with carvedilol had no adverse events. CONCLUSIONS: Serum concentrations of h-FABP and BNP can be used as biomarkers to evaluate the severity of heart failure, and carvedilol can significantly improve heart function in children with CHF.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Carbazóis/uso terapêutico , Proteínas de Ligação a Ácido Graxo/sangue , Insuficiência Cardíaca/tratamento farmacológico , Peptídeo Natriurético Encefálico/sangue , Propanolaminas/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Antagonistas Adrenérgicos beta/efeitos adversos , Fatores Etários , Biomarcadores/sangue , Carbazóis/efeitos adversos , Carvedilol , Criança , Pré-Escolar , China , Doença Crônica , Ecocardiografia , Ensaio de Imunoadsorção Enzimática , Proteína 3 Ligante de Ácido Graxo , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Lactente , Masculino , Contração Miocárdica/efeitos dos fármacos , Valor Preditivo dos Testes , Propanolaminas/efeitos adversos , Índice de Gravidade de Doença , Volume Sistólico/efeitos dos fármacos , Resultado do Tratamento
8.
Lipids Health Dis ; 14: 25, 2015 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25890021

RESUMO

BACKGROUND: Apolipoprotein E (ApoE) participates in lipoprotein metabolism and immune regulation. This study assessed association between ApoE polymorphisms with hyperuricemia and uric acid metabolism in Uygur men, Xinjiang, China. METHODS: A total of 474 hyperuricemia patients and 518 healthy male controls were recruited from the Health Screening Center, Uygur region of Xinjiang, China and subjected to ApoE genotyping using a multiplex amplification refractory mutation system PCR. RESULTS: Apolipoprotein E3/3 genotype was the predominant type with a frequency of 67.7%, while E2/2 was lower than E4/4 in Uygur males. The frequencies of ApoE2, E3, and E4 alleles were 8.5%, 80.1% and 11.4%, respectively. Distribution of ApoE genotypes was significantly different in hyperuricemia patients from the healthy controls (p<0.001). Particularly, the frequency of ApoE E3/3 was 71.7%, E2/3 9.3%, E3/4 9.3%, E4/4 3.2%, E2/4 2.3%, and E2/2 0.2% in patients vs. 68.1%, 4.6%, 2.9%, 12%, 0.6%, and 4.6% in controls, respectively. Moreover, frequency of ApoE E2 allele was greater in the healthy controls than in patients (p<0.001) and the highest level of uric acid occurred in those with ApoE2/4 and E3/4 genotypes, whereas the lowest uric acid level occurred in those with ApoE E2/2 genotype. In addition, the subjects with the ApoE2 allele had a lower uric acid and LDL-C level than those with the ApoE3 allele and ApoE4 allele (p<0.05). The risk of developing hyperuricemia in subjects without the ApoE2 allele was 1.7 fold higher than those subjects with the ApoE2 allele. CONCLUSIONS: This study revealed frequencies and distributions of ApoE alleles and genotypes in Uygur males, which are different from Han Chinese. ApoE E4 was associated with a slightly higher risk of primary hyperuricemia, whereas ApoE E2 was associated with reduced risk of primary hyperuricemia and LDL-C level.


Assuntos
Apolipoproteínas E/genética , Hiperuricemia/genética , Alelos , Apolipoproteína E2/genética , Apolipoproteína E3/genética , Apolipoproteína E4/genética , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Estudos de Associação Genética , Genótipo , Humanos , Hiperuricemia/etiologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético/genética , Fatores de Risco , Ácido Úrico/sangue , Ácido Úrico/metabolismo , População Branca/genética
9.
ScientificWorldJournal ; 2014: 393628, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24516367

RESUMO

OBJECTIVE: To investigate the prevalence of nonalcoholic fatty liver disease (NAFLD) and the association of serum uric acid level with NAFLD in Uygur people, Xinjiang. METHODS: A total of 2241 Uyghur persons (1214 males and 1027 females) were interviewed for physical checkups from 2011 to 2012. The clinical data of questionnaire survey, body mass index (BMI), abdominal circumference, blood pressure, blood sugar, blood lipid, and serum uric acid level were collected for analysis. RESULTS: The prevalence rates of NAFLD determined by abdominal ultrasound examination and hyperuricemia were 43.9% and 8.4%, respectively. The persons with NAFLD had significantly higher serum uric acid levels than those without NAFLD (320 ± 88 versus 254 ± 80 µ mol/L; P < 0.001). The prevalence rate of NAFLD was significantly higher in subjects with hyperuricemia than that in those without hyperuricemia (78.19% versus 40.83%; P < 0.001), and the prevalence rate increased with progressively higher serum uric acid levels (P < 0.001). Multiple regression analysis showed that hyperuricemia was associated with an increased risk of NAFLD (odds ratio (OR): 2.628, 95% confidence interval (CI): 1.608-4.294, and P < 0.001). CONCLUSION: Serum uric acid level was significantly associated with NAFLD, and the prevalence rate of NAFLD increased with progressively higher serum uric acid levels.


Assuntos
Etnicidade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Ácido Úrico/sangue , Adulto , Idoso , China/epidemiologia , China/etnologia , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
10.
Transgenic Res ; 22(4): 805-12, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23328918

RESUMO

The feasibility of using the pig parotid secretory protein promoter to drive the ß-glucanase transgene expression in mouse parotid glands was examined in this study. The parotid gland-specific vector expressing ß-glucanase gene (GLU, from Paenibacillus polymyxa CP7) was constructed. Transgenic mice were produced by the pronuclear microinjection. Both PCR and Southern blot analysis showed that the mice carried the ß-glucanase gene and the ß-glucanase gene could be stably inherited. Furthermore, RT-PCR and northern blot analysis indicated that it was specifically expressed in the parotid. The ß-glucanase activity in the saliva was found to be 0.18 U/mL. After feeding a diet containing 2 % ß-glucan, the average daily gain of transgenic was significantly higher than non-transgenic mice. The crude protein and crude fat concentration in faeces of transgenic mice were significantly reduced compared with that of the non-transgenic mice. These results suggest that the successful expression of foreign ß-glucanase in the animal parotid would offer a promising biological approach to reduce the anti-nutritional effect of ß-glucans in feed.


Assuntos
Glucanos/genética , Glicosídeo Hidrolases/genética , Glândula Parótida/metabolismo , Proteínas e Peptídeos Salivares/genética , Animais , Regulação da Expressão Gênica/genética , Glucanos/metabolismo , Glicosídeo Hidrolases/biossíntese , Camundongos , Camundongos Transgênicos , Paenibacillus , Proteínas e Peptídeos Salivares/biossíntese
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 15(2): 99-101, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23428121

RESUMO

OBJECTIVE: To study serum levels of heart-type fatty acid-binding protein (h-FABP) in children with chronic heart failure (CHF), and the correlation between heart function and the level of h-FABP, with the aim of studying the significance of h-FABP in CHF. METHODS: Thirty-six children with CHF, including 16 cases of endocardial fibroelastosis (EFE) and 20 cases of dilated cardiomyopathy (DCM) were enrolled in the study. Thirty healthy children sevred as the control group. Serum levels of h-FABP were determined using ELISA, and left ventricular ejection fraction (LVEF), cardiac index (CI) and fractional shortening of the left ventricle (LVSF) were measured by two-dimensional echocardiography in the CHF group. RESULTS: Mean levels of h-FABP in the CHF group were significantly higher than in the control group (21.7±4.3 ng/mL vs 6.2±1.7 ng/mL; P<0.01). The worse the heart function, the higher the h-FABP levels (P<0.01). Mean levels of h-FABP in both the EFE and DCM groups were significantly higher than in the control group (P<0.01). Serum h-FABP concentrations were negatively correlated with LVEF, CI and LVSF (r=-0.65, -0.64 and -0.71 respectively; P<0.01) in the CHF group. CONCLUSIONS: Serum h-FABP levels increase in children with CHF and are closely related to the severity of the condition. Serum h-FABP levels can be used as a biomarker for the diagnosis of heart failure and the evaluation of its severity.


Assuntos
Proteínas de Ligação a Ácido Graxo/sangue , Insuficiência Cardíaca/sangue , Cardiomiopatia Dilatada/sangue , Criança , Pré-Escolar , Doença Crônica , Fibroelastose Endocárdica/sangue , Proteína 3 Ligante de Ácido Graxo , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Lactente , Masculino , Índice de Gravidade de Doença
12.
Biomed Res Int ; 2022: 1427607, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36051474

RESUMO

Polymorphisms have been identified to predispose to primary gouty arthritis (GA) and hyperuricemia (HUA). Here, we accessed the five polymorphisms of rs10754558, rs35829419, rs3738448, rs3806268, and rs7525979 in NLRP3 on GA and HUA susceptibility. We collected 1198 samples (314 GA, 377 HUA, and 507 controls) for this case-control study. Our data detected that the rs3806268 (GA vs. AA: OR = 0.65, p = 0.012) was significantly associated with the susceptibility to GA. The rs3738448 (TT vs. GG: OR = 2.05, p = 0.024) and rs7525979 (TT vs. CC: OR = 1.96, p = 0.037) were significantly associated with the susceptibility to HUA. The rs3806268 AG genotype presented decreased risk of GA among the hypertension (OR = 0.54, p = 0.0093), smoking (OR = 0.59, p = 0.018), and no obesity (OR = 0.60, p = 0.0097) subjects compared to the GG genotype group. The rs3738448 TT genotype demonstrated increased risk of HUA among the hypertension (OR = 4.10, p = 0.0056) and no drinking population (OR = 3.56, p = 0.016) compared to the GG genotype group. The rs7525979 TT genotype demonstrated increased risk of HUA among the hypertension (OR = 4.01, p = 0.0064) and no drinking population (OR = 3.24, p = 0.034) compared to the CC genotype group. Furthermore, a significant haplotype effect of rs10754558/C-rs35829419/C-rs3738448/G-rs3806268/A-rs7525979/C was found (OR = 1.60, p = 0.0046) compared with GCGAC haplotype. Bioinformatics analyses indicated that rs3738448, rs3806268, and rs7525979 might influence the gene regulation, while the T-allele of rs3738448 increased the stability of NLRP3-mRNA. Collectively, our case-control study confirms NLRP3 polymorphisms might participate in regulating immune and inflammation responses in GA and HUA.


Assuntos
Artrite Gotosa , Hipertensão , Hiperuricemia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Artrite Gotosa/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Hipertensão/genética , Hiperuricemia/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Polimorfismo de Nucleotídeo Único
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 12(3): 169-71, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20350422

RESUMO

OBJECTIVE: To study serum levels of brain natriuretic peptide (BNP) in children with Kawasaki disease (KD) and the correlation between BNP levels and the heart function. METHODS: Forty-three children with KD and thirty healthy children were enrolled. Serum levels of BNP were measured using ELISA. KD children received an echocardiographic examination, including measurements of left ventricular ejection fraction (LVEF), left ventricular shorten fraction (LVSF), cardiac index (CI) and left ventricular inflow velocity through the mitral annulus. RESULTS: Mean serum level of BNP at the acute stage in children with KD was significantly higher than that at the recovery stage as well as the control group (p<0.01). The LVEF, LVSF and CI levels at the acute stage were significantly lower than those at the recovery stage in children with KD (p<0.05). The linear regression analysis showed that the BNP level was negatively correlated with the levels of LVEF, LVSF and CI (r=-0.63, -0.52, -0.53, p<0.05). CONCLUSIONS: The serum BNP levels increase significantly in KD children at the acute stage, and are negatively correlated with the levels of LVEF, LVSF and CI. Measurement of serum BNP level is useful for the early diagnosis of KD.


Assuntos
Coração/fisiopatologia , Síndrome de Linfonodos Mucocutâneos/sangue , Peptídeo Natriurético Encefálico/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/fisiopatologia
14.
J Nanosci Nanotechnol ; 20(2): 1098-1108, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383110

RESUMO

In this study, the 2D porous graphitic carbon nitride (g-C3N4) nanosheets were successfully fabricated via a facile thermal decomposition polymerization method without any help of templates, and then novel porous g-C3N4/CdS complex catalysts of different mass fractions were is situ synthesized by a simple solvothermal process. The results of photocatalytic experiments demonstrate that the coupling g-C3N4/CdS cocatalysts exhibit significant enhanced visible-light-driven photocatalytic activity for the decolorization of methyl orange (MO) compared with individual porous g-C3N4 and CdS. In particular, an optimal porous g-C3N4 content in the hybridized composite has been determined to be 70 wt.%, corresponding to pseudo-first-order rate constant of 0.046 min-1, which is 7 and 11 times faster than that of pure porous g-C3N4 and CdS, respectively. Photoluminescence (PL) spectroscopy measurements clearly confirmed that the recombination of photoproduced electrons and holes in g-C3N4/CdS composites was efficiently inhibited due to the formation of heterojunctions. Furthermore, the possible mechanism of enhanced photocatalytic activity and photostability of prous g-C3N4/CdS are also tentatively proposed.

15.
Nanoscale ; 12(3): 1994-2001, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31912077

RESUMO

As a single-elemental system, tellurium can exist stably in the form of layers with an intriguing multivalence character, which constructs a new member of the 2D family. However, the growth and electronic structure of tellurium films are still far from known at present. Here, combined with molecular beam epitaxy, scanning tunneling microscopy/spectroscopy measurements and density functional theory calculations, we report the geometric and electronic structures of tellurium grown on NbSe2 from sub-monolayer to few-layer films. At the sub-monolayer coverage, we obtain two types of adatom-induced ordered superstructures that are strongly coupled with NbSe2. With the increase in coverage, the few-layer tellurium films adopt the α-phase form, showing internal strain-induced ripple patterns in the few-layers and bulk-like in thick layers with distinct edge geometries. The band gap of α-tellurium films decreases with the increase in thickness, which is associated with notable in-gap states. These observations, corroborated with DFT calculations, emphasize the important role of the NbSe2 substrate in modulating the structural and electronic properties of tellurium films. Moreover, the interaction between tellurium adatoms and tellurium films leads to √2 × âˆš2 surface reconstruction prior to a new monolayer, conforming to our theoretical calculations. Our work clarifies the kinetic growth of tellurium films on NbSe2 and reveals the tunability of electronic properties via substrate modulation or surface decoration.

16.
ACS Appl Mater Interfaces ; 12(38): 43173-43179, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32833418

RESUMO

Quasi-two-dimensional (quasi-2D) materials hold promise for future electronics because of their unique band structures that result in electronic and mechanical properties sensitive to crystal strains in all three dimensions. Quantifying crystal strain is a prerequisite to correlating it with the performance of the device and calls for high resolution but spatially resolved rapid characterization methods. Here, we show that using fly-scan nano X-ray diffraction, we can accomplish a tensile strain sensitivity below 0.001% with a spatial resolution of better than 80 nm over a spatial extent of 100 µm on quasi-2D flakes of 1T-TaS2. Coherent diffraction patterns were collected from a ∼100 nm thick sheet of 1T-TaS2 by scanning a 12 keV focused X-ray beam across and rotating the sample. We demonstrate that the strain distribution around micron- and submicron-sized "bubbles" that are present in the sample may be reconstructed from these images. The experiments use state-of-the-art synchrotron instrumentation and will allow rapid and nonintrusive strain mapping of thin-film samples and electronic devices based on quasi-2D materials.

17.
Curr Med Sci ; 39(2): 243-249, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31016517

RESUMO

EN: Summary]This study aimed to test the effects of five single nucleotide polymorphisms within SLC2A9 on uric acid level in a special ethnic population, the Uygurs in Xinjiang, China. According to our inclusion and exclusion criteria, Uygur adults from Xinjiang constituted the study population. There were 1053 Uygur adults with hyperuricemia and 1373 normal Uygur adults who served as controls. Five single nucleotide polymorphisms within SLC2A9 (rs938557, rs7679916, rs7349721, rs13101785, and rs13137343) were selected with the HapMap dataset and TaqMan assays. We found that, in normouricemia group, rs938557 was significantly correlated with uric acid (ß=11.39±3.74, P=0.0024) adjusting for age, gender and BMI; rs7679916 and rs13137343 were marginally associated with uric acid concentration (ß=5.77±3.09, P=0.0626; ß= 5.99±3.08, P=0.0520). In the hyperuricemia group, no SNP was found to possibly influence uric acid concentration. None of these SNPs showed significant association with hyperuricemia after controlling for age, gender and BMI. There were significant or marginal correlations between certain single nucleotide polymorphisms in the SLC2A9 region and uric acid concentration in Uygur normouricemia samples. In turn, some of these single nucleotide polymorphisms in SLC2A9 may increase the risk of hyperuricemia.


Assuntos
Predisposição Genética para Doença/genética , Proteínas Facilitadoras de Transporte de Glucose/genética , Hiperuricemia/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Povo Asiático/genética , China , Estudos Transversais , Feminino , Frequência do Gene/genética , Humanos , Hiperuricemia/metabolismo , Masculino , Pessoa de Meia-Idade , Ácido Úrico/metabolismo
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 10(3): 304-6, 2008 Jun.
Artigo em Zh | MEDLINE | ID: mdl-18554454

RESUMO

OBJECTIVE: To assess the values of serum fatty acid-binding protein (FABP) and brain natriuretic peptide (BNP) in pneumonia complicated by acute congestive heart failure (CHF) in children. METHODS: Serum levels of FABP and BNP were determined using ELISA in 36 children with pneumonia complicated by CHF (pneumonia group) and 28 healthy children (control group). RESULTS: Serum levels of FABP and BNP in the pneumonia group at the acute stage were significantly higher than those in the control group and those at the recovery stage (P<0.01). Compared with the control group, serum levels of FABP and BNP in the pneumonia group at the recovery stage increased significantly (P<0.01). At the acute stage, 35 patients (97.2%) showed increased serum FABP level but 28 (77.8%) showed increased serum BNP level (P<0.05) in the pneumonia group. At the recovery stage, the incidence of abnormal serum FABP (72.2%) was significantly higher than that of BNP (44.4%) in the pneumonia group (P<0.05). CONCLUSIONS: Serum levels of FABP and BNP can be regarded as biochemical markers of myocardial damage in children with pneumonia complicated by CHF and serum FABP appears to be a more sensitive one. Serum FABP and BNP remained at higher levels through the recovery stage, suggesting that myocardial damage existed though the clinical symptoms were improved at the stage.


Assuntos
Proteínas de Ligação a Ácido Graxo/sangue , Insuficiência Cardíaca/sangue , Peptídeo Natriurético Encefálico/sangue , Pneumonia/complicações , Doença Aguda , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
19.
Zhongguo Dang Dai Er Ke Za Zhi ; 10(2): 136-8, 2008 Apr.
Artigo em Zh | MEDLINE | ID: mdl-18433529

RESUMO

OBJECTIVE: This study examined serum level of heart-type fatty acid-binding protein (h-FABP) in children with Kawasaki disease (KD) in order to assess its value in KD. METHODS: Forty children with KD and 30 healthy children were enrolled. Serum levels of h-FABP and cardiac troponin I (cTnI) were measured using ELISA. Serum creatine kinase-MB (CK-MB) level was detected using an autoanalyer. The KD group was classified into two subgroups, with or without coronary artery lesions, based on the findings of the echocardiography. RESULTS: Mean serum levels of h-FABP (18.17+/-13.38 ng/mL vs 6.25+/-1.70 ng/mL; P<0.01) and cTnI (0.27+/-0.22 ng/mL vs 0.11+/-0.02 ng/mL; P<0.05) in the KD group was significantly higher than those in the control group. There was no significant difference in serum CK-MB concentrations between the two groups. Twenty-six patients (65%) and eight patients (20%) showed abnormally increased h-FABP and cTnI levels respectively in the KD group, but none of the control group showed increased levels of both. In the KD group, the percentage of patients with increased h-FABP was significantly higher than those with increased CTnI (P<0.01). The patients with coronary artery lesions had higher serum h-FABP level than those without (28.14+/-14.26 ng/mL vs 11.52+/-6.28 ng/mL; P<0.01). CONCLUSIONS: Serum levels of h-FABP and cTnI increase and can be used as the biomarkers of myocardial damage in children with KD. h-FABP appears to be more sensitive and specific. Detection of serum h-FABP level is useful for diagnosis of KD and coronary artery lesions secondary to KD.


Assuntos
Proteínas de Ligação a Ácido Graxo/sangue , Síndrome de Linfonodos Mucocutâneos/sangue , Criança , Pré-Escolar , Creatina Quinase Forma MB/sangue , Proteína 3 Ligante de Ácido Graxo , Feminino , Humanos , Lactente , Masculino , Troponina I/sangue
20.
Nanoscale Res Lett ; 13(1): 250, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30136049

RESUMO

Hierarchical SnO2 blooming nanoflowers were successfully fabricated via a simple yet facile hydrothermal method with the help of different surfactants. Here we focus on exploring the promotion effects of surfactants on the self-assembly of 2D SnO2 nanosheets into 3D SnO2 flower-like structures as well as their gas-sensing performances. The polyporous flower-like SnO2 sensor exhibits excellent gas-sensing performances to ethanol and H2S gas due to high porosity when polyvinyl pyrrolidone is added into the precursor solution as a surfactant. The response/recovery times were about 5 s/8 s for 100 ppm ethanol and 4 s/20 s for 100 ppm H2S, respectively. Especially, the maximum response value of H2S is estimated to be 368 at 180 °C, which is one or two orders of magnitude higher than that of other test gases in this study. That indicates that the sensor fabricated with the help of polyvinyl pyrrolidone has good selectivity to H2S.

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