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1.
Nanomaterials (Basel) ; 14(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38607159

RESUMO

The rapid development of the photovoltaic industry has also brought some economic losses and environmental problems due to the waste generated during silicon ingot cutting. This study introduces an effective and facile method to reutilize silicon-cutting waste by constructing a multilayer Si@SiO2@C composite for Li-ion batteries via two-step annealing. The double-layer structure of the resultant composite alleviates the severe volume changes of silicon effectively, and the surrounding slightly graphitic carbon, known for its high conductivity and mechanical strength, tightly envelops the silicon nanoflakes, facilitates ion and electron transport and maintains electrode structural integrity throughout repeated charge/discharge cycles. With an optimization of the carbon content, the initial coulombic efficiency (ICE) was improved from 53% to 84%. The refined Si@SiO2@C anode exhibits outstanding cycling stability (711.4 mAh g-1 after 500 cycles) and rate performance (973.5 mAh g-1 at 2 C). This research presents a direct and cost-efficient strategy for transforming photovoltaic silicon-cutting waste into high-energy-density lithium-ion battery (LIB) anode materials.

2.
Phlebology ; 38(2): 103-114, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36601900

RESUMO

BACKGROUND: Peripherally inserted central catheter (PICC) is widely used in clinical practice because of its long retention time and easy maintenance. However, PICC-associated venous thromboembolism (VTE) is the most serious complication of PICC. Guidelines recommend exercise therapy to prevent PICC-associated VTE. However, inconsistent findings have been reported across the literature. This study conducted a meta-analysis to further evaluate the effect of exercise therapy on PICC-associated VTE. METHODS: We searched CNKI, Wanfang database, Chinese Science and Technology Journal Full Text Database, PubMed, Embase, Web of Science and Cochrane Library databases and included all randomized controlled trials (RCTs) of exercise therapy for the prevention of PICC-associated VTE. Two investigators independently screened the literature, extracted information, and evaluated the risk of bias for eligible RCTs. Meta-analysis was conducted by RevMan5.4 software. RESULTS: Eleven RCTs were included, including 1919 patients. Meta-analysis showed that the incidence of PICC-associated VTE was lower in the exercise therapy group than in the usual care group (RR = 0.30, 95% CI: 0.22-0.41, p < 0.00001).Exercise therapy increased the axillary vein maximum velocity (SMD = 0.93, 95% CI: 0.58-1.28, p < 0.00001) and the axillary vein time-mean flow velocity (SMD = 0.86, 95% CI: 0.53-1.20, p < 0.00001). Subgroup analysis showed statistically significant differences for the incidence of PICC-associated VTE for intervention times<4 weeks (RR = 0.26, 95% CI: 0.17-0.40, p < 0.00001) and intervention times≥4 weeks (RR = 0.35, 95% CI: 0.22-0.54, p < 0.00001). For axillary vein maximum velocity, the difference was statistically significant for both intervention time <4 weeks (SMD = 0.73, 95% CI: 0.55-0.91, p < 0.00001) and intervention time ≥4 weeks (SMD = 1.18, 95% CI: 0.18-2.19, p = 0.02). For axillary vein time-mean flow velocity, the intervention time <4 weeks (SMD = 0.75, 95% CI: 0.46-1.04, p < 0.00001), and the difference was statistically significant; while ≥4 weeks, the difference was not statistically significant (SMD = 1.14, 95% CI: -0.07 to 2.35, p = 0.06). CONCLUSIONS: Exercise therapy improved venous blood flow velocity and effectively reduced the incidence of PICC-associated VTE. However, RCTs with large samples and high quality are needed to further evaluate the effectiveness of exercise therapy in PICC patients.


Assuntos
Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiologia , Terapia por Exercício , Veias
3.
J Colloid Interface Sci ; 629(Pt B): 263-269, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36155921

RESUMO

Two-dimensional (2D) material Ti3C2 MXenes have recently been used in electrode composites for lithium-ion batteries (LIBs) for their excellent electrical conductivity and accordion-like nanosheet morphology. However, Ti3C2 has low specific capacity and fast degradation rate upon cycling after inevitably coupling with surface species during synthesis. In this work, Ti3C2 is used as Ti-source for Li4Ti5O12 (LTO) and C-source for carbon quantum dots (CQDs) in a one-step hydrothermal process. The resultant LTO product (M-LTO) inherits the nanosheet morphology of Ti3C2 with uniformly anchored CQDs. The highly electronic conductive CQDs optimize the transmission path of ions which reduces the diffusion barrier of ions, and they further increase the density of states of the material which effectively improving the conductivity of M-LTO. Remarkable electrochemical performances including high initial specific capacity, long lifetime and excellent low temperature capacity are demonstrated for this type of electrode in LIBs, sodium ion batteries (SIBs) and lithium-magnesium ion hybrid batteries (LMIHBs). This paper offers a new strategy to the rapidly expanding research on the application of transition metal MXenes in electrodes for metal-ion batteries.

4.
ACS Appl Mater Interfaces ; 14(2): 2805-2816, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35000387

RESUMO

To meet the rapidly growing and diversified demand for energy storage, advanced rechargeable batteries with high-performance materials and efficient battery configuration are widely being exploited and developed. Bipolar-stacked electrode coupling with solid-state electrolytes enables achieving batteries with high output voltage, high energy density, and simple components. Here, a polymer electrolyte membrane is designed with polyethylene oxide containing bis(trifluoromethanesulfonyl)-imide as the electrolyte, succinonitrile as the plasticizer, and nylon mesh as a reinforcement for the bipolar-stacked battery. The as-prepared nylon mesh-reinforced polymer electrolyte membrane shows advantageous features, that is, excellent ionic conductivity (3.38 × 10-4 S cm-1) at room temperature, low interface impedance, and good tolerance against the expansion caused by the plating/stripping of the Li anode and the electrode upon cycling. When used as a polymer electrolyte membrane in the bipolar-stacked battery, the LiFePO4(LFP)-Li4Ti5O12(LTO) cell with three cells connected in series delivers a higher discharge voltage (5.4 V) and a volumetric energy density (0.328 mW h cm-3), nearly 3 times as much as that of the LFP-LTO battery. In addition, LiFePO4-Li pouch cells using the polymer electrolyte membrane can sustain the abuse tests including bending, cutting, and nail penetration well. These results pave a new avenue to develop high-performance polymer electrolyte membranes and allow for the design of high-voltage and volumetric energy density bipolar-stacked batteries.

5.
Int J Med Mushrooms ; 23(9): 45-53, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34591397

RESUMO

Tricholoma matsutake is popular in Asian countries because of its edibility and medicinal use. T. matsutake is a precious natural medicinal fungus, and it is widely used in food and biological products. This study aimed to explore the mechanism of T. matsutake on promoting proliferation of human immortalized keratinocyte (HaCaT) cells and accelerating wound healing in mice. The MTT assay was used to test the effects of three different T. matsutake extracts (0, 62.5, 125, 250, 500, and 1000 µg/mL) on HaCaT cell viability. HaCaT cells were treated with the three T. matsutake extracts (100, 500 µg/mL) and morphological and biophysical properties were detected by atomic force microscopy with JPK data processing. Western blot analysis detected Notch signaling pathways of HaCaT cells treated with 50% ethanol extract of T. matsutake (50%T) for 24 h (100, 500 and 1000 µg/mL). Mouse wounds were treated with 50%T for 15 days. Wound healing effects were observed on the back skin of mice at different times. The quality of wound healing was estimated by histological staining (hematoxylin and eosin and Masson's trichrome). All data were counted by GraphPad Prism 5 software. The increased concentration of T. matsutake remarkably promoted HaCaT cell proliferation. The Young's modulus of HaCaT cells showed the biggest increase from 1.73 ± 0.13 kPa (0 µg/mL) to 4.57 ± 0.16 kPa (500 µg/mL) in the 50%T group. The Notch1/Jagged1 pathways were upregulated with an increase in concentration (0, 100, 500, and 1000 µg/mL). Moreover, compared with the negative and positive control groups, T. matsutake promoted wound healing in mice by epidermal regeneration, subepidermal tissue formation, and collagen deposition. The results showed that T. matsutake promotes not only proliferation of HaCaT cells but also wound healing in mice.


Assuntos
Tricholoma , Agaricales , Animais , Proliferação de Células , Células HaCaT , Humanos , Camundongos , Cicatrização
6.
Hum Immunol ; 80(3): 195-203, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576702

RESUMO

T cell receptors (TCRs) are a class of T cell surface molecules that recognize the antigen-derived peptides presented by the major histocompatibility complex (MHC) and are able to trigger a series of immune responses. TCRs are important members of the adaptive immune system that arose in the jawed fish 500 million years ago. T cell receptor beta variable (TRBV) genes have been widely used to characterize TCR repertoires. Studying the evolution of TRBV may help us to better understand the adaptive immune system. To investigate TRBV evolution and its impacts on the usages of TRBV genes in human populations, we compared the TRBV genes and their homologous sequences among humans, mouse, rhesus and chimpanzee, analyzed the single-nucleotide polymorphisms (SNPs) located at TRBV loci, and sequenced TCR repertoires in the peripheral blood of 97 healthy donors. We found that functional TRBVs are more evolutionarily conserved but possess more SNPs in human populations than do nonfunctional (pseudo) TRBVs. Based on the conservation levels in the four species, we classified the functional TRBVs into 2 groups: old (conserved between mouse and humans) and new (conserved only in primates). The new TRBVs evolve faster and possess more SNPs than the old TRBVs. The variations in TRBV genes frequencies in the peripheral blood of healthy donors are negatively correlated with SNP density. These observations suggest that TRBV usages may be influenced by TCR-MHC co-evolution.


Assuntos
Evolução Molecular , Variação Genética , Genética Populacional , Polimorfismo de Nucleotídeo Único , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Animais , Voluntários Saudáveis , Humanos , Camundongos , Filogenia , Primatas , Linfócitos T/metabolismo
7.
RSC Adv ; 8(18): 9795-9801, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35540825

RESUMO

Li2MnSiO4 compounded with indium tin oxide (ITO) was successfully synthesized through a sol-gel method. The structure and morphology characterization of Li2MnSiO4/ITO nanocomposite are demonstrated by XRD, SEM, TEM, EDS and XPS. Galvanostatic charge-discharge tests, EIS and CV are employed to examine the electrochemical performance of the composite. From those results, it could be observed that the electrochemical performance of Li2MnSiO4 cathode material has been significantly improved due to the introducing of indium tin oxide. The 3 wt% ITO-compounded sample displayed a discharge specific capacity around 141 mA h g-1 at 0.05C, 134.4 mA h g-1 at 0.1C, 132.9 mA h g-1 at 0.2C and 127.4 mA h g-1 at 0.5C in the first cycle, which is much higher than the pristine sample.

8.
Zhonghua Gan Zang Bing Za Zhi ; 16(4): 279-82, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18423150

RESUMO

OBJECTIVE: To study the responses of peginterferon-alpha 2a antiviral therapy in chronic hepatitis B (CHB) patients. METHODS: One hundred two CHB patients with their serum ALT values higher than 2x the upper limit of the normal (ULN) were divided into a HBeAg-positive and a HBeAg-negative group. All patients were treated with peginterferon-alpha 2a by subcutaneous injection (180 microgram once weekly). After treatment for 6 months, patients without a defined therapeutic response were dropped from the treatment group; the others completed a 12 month therapy. The sustained response and the antiviral effect of the treatment were assessed at the end of the therapy. To investigate the possible impact factors of the response to peginterferon-alpha 2a, we studied the therapeutic response of patients with different serum ALT levels, inflammation grades of liver histology, stages of fibrosis, and HBV viral load levels. RESULTS: (1) There was no statistical difference of the rates of response at the end of treatment and 6, 12, 18, 24 and 30 months after the cessation of therapy between the HBeAg-positive and the HBeAg-negative groups. (2) In the HBeAg-positive group, the rates of response of patients with serum ALT values>3*ULN were significantly higher than those with serum ALT values less than 3*ULN (x2=4.40). However, no statistical difference of serum ALT levels was found in the HBeAg-negative group. (3) In both HBeAg-positive and HBeAg-negative groups, no difference was revealed in the rates of response among patients with different levels of HBV viral loads. (4) In the HBeAg-positive group, patients with more severe liver inflammation histologically (G3 and G4) had significantly higher response rates than those with milder inflammation (G1 and G2) (x2=4.19), but no similar statistical differences were found in the HBeAg-negative group. Moreover, there was no difference in the rates of response among patients in different stages of liver fibrosis in both HBeAg-positive and HBeAg-negative groups. CONCLUSIONS: Similar rates of response and sustained virological response to the peginterferon-alpha 2a treatment can be achieved in both HBeAg-positive and HBeAg-negative patients. Hepatic fibrosis is not a predictor of poor therapeutic response. For HBeAg-positive patients, more severe liver inflammation identified with liver biopsies (G3 or G4) and high serum ALT values (more than 3*ULN) can be considered as predictors of a good therapeutic response.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Feminino , Hepatite B Crônica/patologia , Humanos , Interferon alfa-2 , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Adulto Jovem
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