The synergy effect on Li storage of LiFePO4 with activated carbon modifications

In this work, composite electrodes containing lithium iron phosphate (LiFePO) and activated carbon (AC) were prepared by physically mixing LiFePO and AC with polyvinylidene fluoride (PVDF) as a binder and acetylene black (AB) as an electrically conductive agent. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), nitrogen sorption, four-probe conductivity and vibrating densitometer techniques were employed to characterize samples. The characterization results showed that the presence of AC increased the electrical conductivity, reduced the tap density, and modified the porosity of the resultant composite electrode materials. Electrochemical data demonstrated that the composite electrode displayed a significantly improved electrochemical performance in comparison with the pure LiFePO electrode. An electrode with 5 wt% AC exhibited specific discharge capacities of 70 mA h g at 20 C and 100 mA h g at 10 C without significant capacity decay after 400 cycles. Galvanostatic charge-discharge and cyclic voltammetry results revealed that energy was stored via both charge adsorption and lithium intercalation/deintercalation owing to the presence of both AC and LiFePO in the composite electrode. Electrochemical impedance spectroscopy (EIS) was used to investigate the charge-discharge kinetics and mechanism of the composite electrode. The EIS results demonstrated that the two different active materials (LiFePO and AC) displayed synergy in terms of both material structure and energy storage, contributing to the observed excellent electrochemical performance

Nitric Oxide Enhances Desiccation Tolerance of Recalcitrant Antiaris toxicaria Seeds via Protein S-Nitrosylation and Carbonylation

The viability of recalcitrant seeds is lost following stress from either drying or freezing. Reactive oxygen species (ROS) resulting from uncontrolled metabolic activity are likely responsible for seed sensitivity to drying. Nitric oxide (NO) and the ascorbate-glutathione cycle can be used for the detoxification of ROS, but their roles in the seed response to desiccation remain poorly understood. Here, we report that desiccation induces rapid accumulation of H2O2, which blocks recalcitrant Antiaris toxicaria seed germination; however, pretreatment with NO increases the activity of antioxidant ascorbate-glutathione pathway enzymes and metabolites, diminishes H2O2 production and assuages the inhibitory effects of desiccation on seed germination. Desiccation increases the protein carbonylation levels and reduces protein S-nitrosylation of these antioxidant enzymes; these effects can be reversed with NO treatment. Antioxidant protein S-nitrosylation levels can be further increased by the application of S-nitrosoglutathione reductase inhibitors, which further enhances NO-induced seed germination rates after desiccation and reduces desiccation-induced H2O2 accumulation. These findings suggest that NO reinforces recalcitrant seed desiccation tolerance by regulating antioxidant enzyme activities to stabilize H2O2 accumulation at an appropriate concentration. During this process, protein carbonylation and S-nitrosylation patterns are used as a specific molecular switch to control antioxidant enzyme activities

Reduced Bone Mass and Muscle Strength in Male 5α-Reductase Type 1 Inactivated Mice

Androgens are important regulators of bone mass but the relative importance of testosterone (T) versus dihydrotestosterone (DHT) for the activation of the androgen receptor (AR) in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2), encoded by separate genes (Srd5a1 and Srd5a2). 5α-reductase type 2 is predominantly expressed in male reproductive tissues whereas 5α-reductase type 1 is highly expressed in liver and moderately expressed in several other tissues including bone. The aim of the present study was to investigate the role of 5α-reductase type 1 for bone mass using Srd5a1−/− mice. Four-month-old male Srd5a1−/− mice had reduced trabecular bone mineral density (−36%, p<0.05) and cortical bone mineral content (−15%, p<0.05) but unchanged serum androgen levels compared with wild type (WT) mice. The cortical bone dimensions were reduced in the male Srd5a1−/− mice as a result of a reduced cortical periosteal circumference compared with WT mice. T treatment increased the cortical periosteal circumference (p<0.05) in orchidectomized WT mice but not in orchidectomized Srd5a1−/− mice. Male Srd5a1−/− mice demonstrated a reduced forelimb muscle grip strength compared with WT mice (p<0.05). Female Srd5a1−/− mice had slightly increased cortical bone mass associated with elevated circulating levels of androgens. In conclusion, 5α-reductase type 1 inactivated male mice have reduced bone mass and forelimb muscle grip strength and we propose that these effects are due to lack of 5α-reductase type 1 expression in bone and muscle. In contrast, the increased cortical bone mass in female Srd5a1−/− mice, is an indirect effect mediated by elevated circulating androgen levels

Efficacy of non-surgical treatments for androgenetic alopecia: a systematic review and network meta-analysis

Androgenetic alopecia, or male/female pattern baldness, is the most common type of progressive hair loss disorder. The aim of this study was to review recent advances in non‐surgical treatments for androgenetic alopecia and identify the most effective treatments. A network meta‐analysis (NMA) was conducted of the available literature of the six most common non‐surgical treatment options for treating androgenetic alopecia in both men and women; dutasteride 0.5 mg, finasteride 1 mg, low‐level laser therapy (LLLT), minoxidil 2%, minoxidil 5% and platelet‐rich plasma (PRP). Seventy‐eight studies met the inclusion criteria, and 22 studies had the data necessary for a network meta‐analysis. Relative effects show LLLT as the superior treatment. Relative effects show PRP, finasteride 1 mg (male), finasteride 1 mg (female), minoxidil 5%, minoxidil 2% and dutasteride (male) are approximately equivalent in mean change hair count following treatment. Minoxidil 5% and minoxidil 2% reported the most drug‐related adverse events (n = 45 and n = 23, respectively). The quality of evidence of minoxidil 2% vs. minoxidil 5% was high; minoxidil 5% vs. placebo was moderate; dutasteride (male) vs. placebo, finasteride (female) vs. placebo, minoxidil 2% vs. placebo and minoxidil 5% vs. LLLT was low; and finasteride (male) vs. placebo, LLLT vs. sham, PRP vs. placebo and finasteride vs. minoxidil 2% was very low. Results of this NMA indicate the emergence of novel, non‐hormonal therapies as effective treatments for hair loss; however, the quality of evidence is generally low. High‐quality randomized controlled trials and head‐to‐head trials are required to support these findings and aid in the development of more standardized protocols, particularly for PRP. Regardless, this analysis may aid physicians in clinical decision‐making and highlight the variety of non‐surgical hair restoration options for patients

Meta-analysis identifies novel risk loci and yields systematic insights into the biology of male-pattern baldness

Life & Brain GmbH; the BONFOR programme of the University of Bonn; and the Agency for Science, Technology and Research (A*STAR). M.M.N. is a member of the DFG Excellence Cluster ImmunoSensation