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The present study aimed to investigate the effect of androgens on chronic heart failure (CHF) in a rat model. A total of 120 Sprague Dawley male rats were randomly divided into the following groups: (A) sham operation group, (B) castrated group, (C) heart failure (HF) group, (D) castrated + HF group, and (E) castrated + HF + testosterone (T) replacement therapy group. There were 20 rats in group A, and 25 rats in the other groups. Surgical castration was performed on groups B, D and E, and T replacement therapy was administered to group E. Groups C, D and E were treated with doxorubicin hydrochloride to prepare the CHF animal model. The insulin sensitivity index (ISI) was calculated from fasting blood glucose and fasting insulin levels. Echocardiography was performed. Venous blood was collected for plasma T level test. Myocardial tissue was used for apoptosis index analysis. The expression levels of myocardial insulin receptor (IR) and insulin receptor substrate-1 (IRS-1) were measured by reverse transcription semi-quantitative polymerase chain reaction. Compared with group A, the T level and ISI decreased, whereas the expression level of IR and IRS-1 were increased in the CHF group (P<0.05). Following castration, the T level and ISI were significantly decreased, and the expression of IR and IRS-1 were increased compared with the uncastrated CHF rats (P<0.01). Following androgen administration, the ISI increased, expression of IR and IRS-1 decreased, and the myocardial apoptosis index decreased (P<0.05). Taken together, these results demonstrated that androgen supplementation could improve insulin resistance and affect the expression of IR and IRS-1 in CHF, thereby reducing myocardial apoptosis and improving cardiac function. [ABSTRACT FROM AUTHOR]

Abstract: Increasing evidences have shown that dissolved organic components are responsible for the significant C and N exports from terrestrial ecosystems to the surrounding aquatic ecosystems and very sensitive to CO2 enrichment. However, there is still a lack of direct evidence about CO2-led effects on these components at the ecosystem scale, especially in wetlands. We, therefore, simultaneously investigated the contents of dissolved organic carbon (DOC) and dissolved nitrogen (DN) in the surface water and soil layer in a paddy field under FACE facility in Eastern China. Elevated CO2 significantly increased the contents of DOC and DN in the surface water by 18.0% and 14.3% on average. Elevated CO2 also increased DOC content in the soil, but decreased DN content. The contents of DOC and DN in the soil–water interface of 0–1cm soil layer were on average 22.4% and 47.5% higher than in the 5–15cm soil layer. Besides, significant higher DOC and DN contents existed in the soil porewater than in the surface water. Due to multiple drainage regime and rainstorm-induced runoffs in rice cropping regions, CO2-led DOC and DN increments in the surface water may increase C and N exports from paddies to the surrounding aquatic ecosystems under future climate patterns. [Copyright &y& Elsevier]

Copper powder has excellent electrical conductivity, but is easily oxidized by air. This limits its application in printed circuits and related fields. In this paper, graphene was grown in-situ on the surface of dendritic copper powder in order to improve the powders' oxidation resistance and maintain its high electrical conductivity. Firstly, dendritic copper powder with a diameter of about 100-200 nm was prepared by electrochemical deposition. Then, the powder was coated with an amorphous carbon film by Plasma Enhanced Chemical Vapor Deposition (PECVD) using C 2 H 2 at 350 °C. Finally, the amorphous carbon film was transformed into graphene at 850 °C, and dendritic copper powder coated with graphene was obtained. TG-DTA and electrical resistivity measurements showed that the oxidation resistance temperature of dendritic copper powder can be increased from 213.7 °C to 283.4 °C and the resistivity can be reduced from 0.00544 Ω·cm to 0.00308 Ω·cm by in-situ growth of graphene on the surface of copper powder. The in-situ synthesis of graphene is expected to promote the wide application of copper powder in areas requiring high electrical conductivity and oxidation resistance. [Display omitted] • Amorphous carbon is deposited at low temperature and converted into graphene at high temperature. • The oxidation resistance temperature of dendritic copper powder increase 69.7 °C by in-situ growth of graphene. • The resistivity reduced from 0.00544 Ω·cm to 0.00308 Ω·cm by in-situ growth of graphene on the surface of copper powder. [ABSTRACT FROM AUTHOR]

This article proposes a new integral evolution formula of boundary value problem for wave equations of the form u t t (x , t) + L (x , D) u (x , t) = f (x , t). By introducing the operator functions, e.g., ϕ -functions, and using the Duhamel's principle, a compact integral evolution formula is established for inhomogeneous wave equations. The derivation is based on Duhamel's principle and the theory of operational calculus. [ABSTRACT FROM AUTHOR]

The photovoltaic performance of axial and radial pin junction GaAs nanocone array solar cells is investigated. Compared with the cylinder nanowire arrays, the nanocone arrays not only improve the whole optical absorption but more importantly enhance the effective absorption (absorption in the depletion region). The enhanced effective absorption is attributed to the downward shift and extension of the absorption region induced by the shrinking top, which dramatically suppresses the absorption loss in the high-doped top region and enhances the absorption in the depletion region. The highest conversion efficiencies for axial and radial GaAs nanocone solar cells are 20.1% and 17.4%, obtained at a slope angle of 5° and 6°, respectively, both of which are much higher than their cylinder nanowire counterparts. The nanocone structures are promising candidates for high-efficiency solar cells. [ABSTRACT FROM AUTHOR]

Daphnetin is a natural product with anti-inflammatory, antioxidant, and neuroprotective properties. Reports have found that it has a strong analgesic effect; however, its analgesic mechanism is unknown. We explored the effect and mechanism of daphnetin on neuropathic pain (NP). The rat model of NP was established by ligation of the sciatic nerve. Male Sprague-Dawley rats were divided into six groups: Control, Model, Sham, morphine (0.375 mg/kg), and daphnetin (0.0625 and 0.025 mg/kg). Rats were intrathecally injected with drugs or normal saline once daily for three days. Hyperalgesia was evaluated by mechanical withdrawal threshold (MWT) and thermal withdrawal threshold (TWT). Protein levels were detected using ELISA, immunofluorescence, and western blotting. Compared to the Model group, daphnetin improved TWT (46.70 °C vs. 42.20 °C) and MWT (45.60 g vs. 23.60 g), reduced the expression of interleukin-1β (0.99 ng/g vs. 1.42 ng/g), interleukin-6 (0.90 ng/g vs. 1.52 ng/g), and tumor necrosis factor-α (0.93 ng/g vs. 1.52 ng/g) in the sciatic nerve. Daphnetin decreased the expression of toll-like receptor 4 (TLR4) (0.47-fold), phosphorylated inhibitor of NF-κB (p-IKBα) (0.29-fold), nuclear factor kappaB (NF-κB) (0.48-fold), glial fibrillary acidic protein (GFAP) (0.42-fold), CXC chemokine ligand type 1 (CXCL1) (0.84-fold), CXC chemokine receptor type 2 (CXCR2) (0.78-fold) in the spinal cord. Daphnetin alleviates NP by inhibiting inflammation and astrocyte activation in the spinal cord, providing theoretical support for the extensive clinical treatment of NP. [ABSTRACT FROM AUTHOR]