A qualitative study of how self-harm starts and continues among Chinese adolescents

Background It is essential to investigate the experiences behind why adolescents start and continue to self-harm in order to develop targeted treatment and prevent future self-harming behaviours. Aims The aims of this study are to understand the motivations for initiating and repeating nonfatal self-harm, the different methods used between first-time and repeated self-harm and the reasons that adolescents do not seek help from health services. Methods Adolescents with repeated nonfatal self-harm experiences were recruited to participate in individual, semi-structured qualitative interviews. The interviews were analysed with interpretative phenomenological analysis. Results We found that nonfatal self-harm among adolescents occurred comparatively early and was often triggered by specific reasons. However, the subsequent nonfatal self-harm could be causeless, with repeated self-harm becoming a maladaptive coping strategy to handle daily pressure and negative emotions. The choice of tools used was related to the ease of accessibility, the life-threatening risk and the size of the scars. Adolescents often concealed their scars on purpose, which made early identification insufficient. Peer influence, such as online chat groups encouraging self-harm by discussing and sharing self-harm pictures, could also lead to increased self-harm. The results also included participants’ opinions on how to stop nonfatal self-harm and their dissatisfaction with the current healthcare services. Conclusions The current study provides important implications both for early identification and interventions for adolescents who engage in repeated nonfatal self-harm, and for individualising treatment planning that benefits them. It is also worthwhile to further investigate how peer influence and social media may affect self-harm in adolescents

Structure of human immunoproteasome with a reversible and noncompetitive inhibitor that selectively inhibits activated lymphocytes

Proteasome inhibitors benefit patients with multiple myeloma and B cell-dependent autoimmune disorders but exert toxicity from inhibition of proteasomes in other cells. Toxicity should be minimized by reversible inhibition of the immunoproteasome β5i subunit while sparing the constitutive β5c subunit. Here we report β5i-selective inhibition by asparagine-ethylenediamine (AsnEDA)-based compounds and present the high-resolution cryo-EM structural analysis of the human immunoproteasome. Despite inhibiting noncompetitively, an AsnEDA inhibitor binds the active site. Hydrophobic interactions are accompanied by hydrogen bonding with β5i and β6 subunits. The inhibitors are far more cytotoxic for myeloma and lymphoma cell lines than for hepatocarcinoma or non-activated lymphocytes. They block human B-cell proliferation and promote apoptotic cell death selectively in antibody-secreting B cells, and to a lesser extent in activated human T cells. Reversible, β5i-selective inhibitors may be useful for treatment of diseases involving activated or neoplastic B cells or activated T cells

Evolutionary Game Theoretic Modeling and Repetition of Media Distributed Shared in P2P-Based VANET

A significant challenge in vehicular networks is to efficiently provide multimedia services with the constraints of limited resources, high mobility, opportunistic contact, and service time requirements. In order to guarantee the vehicle user satisfaction of multimedia service, with the proliferation of the distributed peer-to-peer (P2P) cooperative transmission technologies, P2P-based VANET has recently received a substantial amount of interest. Using the P2P services thought and at the same time, a set of methods should be designed to avoid the disadvantage of P2P system appearing in VANET. Under such a presupposition, in this paper, we study the media provisions in P2P-based VANET and present a repeated game “More Pay for More Work (RGMPMW)” incentive mechanism based on service evaluation information. We also propose evolutionary game-based veracity (EGV) game model which exploits evolutionary game to guarantee the multimedia service share veracity of all vehicles in VANET. In addition, we provide extensive simulation results that demonstrate the effectiveness of our proposed schemes

Retention fraction of 15N-labelled deposited ammonium and nitrate in forests

The impacts of enhanced nitrogen (N) deposition on global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and its contribution to forest C sink is unclear. We conducted ecosystem-scale paired 15N-labelling experiments in nine forests across China to quantify N retention fractions for both deposited ammonium and nitrate, including tropical and sub-tropical forests for the first time. By combining these results with four previous experiments from temperate Europe and North America, here we show that total ecosystem N retention is similar for ammonium and nitrate, but plants consistently take up more of the labelled nitrate than ammonium while soils retain more ammonium than nitrate. Nitrogen retention in plants and soils across sites is predicted by a combination of tree (NPP and woody biomass) and soil (organic layer mass and soil C/N ratios) variables. Greater proportions of deposited N are retained in N-limited ecosystems with low soil N availability and high soil C/N ratios. We estimate that N deposition-induced C sink in forests contributes more than 20% of the total terrestrial C sink. Although less N is deposited in oxidized than reduced state, their total contributions to the global forest C sink are approximately equal due to more efficient use by trees of the oxidized than the reduced form. Our study demonstrates differential fates of reduced and oxidized N deposition that improves current understanding of the C-N interaction in forests and indicates a greater C sink attributable to atmospheric N deposition than previous estimates

Differential retention of deposited ammonium and nitrate affects the global forest carbon sink

International audienceThe impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired 15 N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate (20 25 15 %) (mean maximum minimum) than ammonium (12 16 8 %) while soils retain more ammonium (57 65 49 %) than nitrate (46 59 32 %). We estimate that the N deposition-induced C sink in forests in the 2010s is 0:72 0:96 0:49 Pg C yr −1 , higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition

Retention of deposited ammonium and nitrate and its impact on the global forest carbon sink

International audienceThe impacts of enhanced nitrogen (N) deposition on the global forest carbon (C) sink and other ecosystem services may depend on whether N is deposited in reduced (mainly as ammonium) or oxidized forms (mainly as nitrate) and the subsequent fate of each. However, the fates of the two key reactive N forms and their contributions to forest C sinks are unclear. Here, we analyze results from 13 ecosystem-scale paired 15 N-labelling experiments in temperate, subtropical, and tropical forests. Results show that total ecosystem N retention is similar for ammonium and nitrate, but plants take up more labelled nitrate (20 25 15 %) (mean maximum minimum) than ammonium (12 16 8 %) while soils retain more ammonium (57 65 49 %) than nitrate (46 59 32 %). We estimate that the N deposition-induced C sink in forests in the 2010s is 0:72 0:96 0:49 Pg C yr −1 , higher than previous estimates because of a larger role for oxidized N and greater rates of global N deposition