Incidence and fatality of serious suicide attempts in a predominantly rural population in Shandong, China: a public health surveillance study

Objectives To estimate the incidence of serious suicide attempts (SSAs, defined as suicide attempts resulting in either death or hospitalisation) and to examine factors associated with fatality among these attempters. Design A surveillance study of incidence and mortality. Linked data from two public health surveillance systems were analysed. Setting Three selected counties in Shandong, China. Participants All residents in the three selected counties. Outcome measures Incidence rate ( per 100 000 person-years) and case fatality rate (%). Methods Records of suicide deaths and hospitalisations that occurred among residents in selected counties during 2009–2011 (5 623 323 person-years) were extracted from electronic databases of the Disease Surveillance Points (DSP) system and the Injury Surveillance System (ISS) and were linked by name, sex, residence and time of suicide attempt. A multiple logistic regression model was developed to examine the factors associated with a higher or lower fatality rate. Results The incidence of SSAs was estimated to be 46 (95% CI 44 to 48) per 100 000 person-years, which was 1.5 times higher in rural versus urban areas, slightly higher among females, and increased with age. Among all SSAs, 51% were hospitalised and survived, 9% were hospitalised but later died and 40% died with no hospitalisation. Most suicide deaths (81%) were not hospitalised and most hospitalised SSAs (85%) survived. The fatality rate was 49% overall, but was significantly higher among attempters living in rural areas, who were male, older, with lower education or with a farming occupation. With regard to the method of suicide, fatality was lowest for non-pesticide poisons (7%) and highest for hanging (97%). Conclusions The incidence of serious suicide attempts is substantially higher in rural areas than in urban areas of China. The risk of death is influenced by the attempter’s sex, age, education level, occupation, method used and season of year

Study of charm hadronization and in-medium modification at the Electron-ion Collider in China

Charm quark production and its hadronization in ep and eA collisions at the future Electron-Ion Collider in China (EicC) will help us understand the quark/gluon fragmentation processes and the hadronization mechanisms in the nuclear medium, especially within a poorly constrained kinematic region ($x<0.1$). In this paper, we report a study on the production of charmed hadrons, $D^0$ and $\Lambda_c^+$, reconstructed with a dedicated GEANT4 simulation of vertex$\,\&\,$tracking detectors designed for EicC. The $\Lambda_c^+$/$D^0$ ratios as functions of multiplicity and $p_T$, as well as the $D^0$ double ratio are presented with projected statistical precision.Comment: 9 pages, 12 figure

Analytical coupling characterization of multi-stage planetary gear free vibration considering flexible structure

The mode characteristics and the parameter sensitivity for a two-stage NGW spur planetary gear system are studied based on the principles of structure natural dynamical characteristics. Considering the influence of flexible structure including shaft, the planet carrier, and the ring-gear, the coupled lateral-torsional-axial vibration dynamical model of the planetary gear system is established under the generalized coordinate system using the shafting element method. With the model, the natural frequency and vibration mode are solved, and the results indicate that the flexibility of ring-gear has a greater effect on natural frequency. Several distinct types of vibration mode are summarized, such as planet torsional mode, sun-gear shaft axial mode, ring-gear axial mode and so on. However, the translational mode which is one of the modes in the coupled lateral-torsional lumped mass model is not found in this study. Within the scope of the time-varying, mesh stiffness mainly affects the planet torsional mode of corresponding stage. Furthermore, the variation of radial bearing stiffness will also do effect on axial vibration mode, and the variation of bearing stiffness not only affects the vibration modes of adjacent stage of planetary gear train, but also affects the nonadjacent stage. The results demonstrate the coupling characteristics of the system under the free vibration condition

A significant reduction in hepatitis B virus infection among the children of Shandong Province, China: the effect of 15 years of universal infant hepatitis B vaccination

AbstractObjectiveTo evaluate the effect of the universal infant hepatitis B vaccination program on hepatitis B infection in China.MethodsIn 2006, a survey was conducted in Shandong Province, China, among children aged 1–14 years, 15 years after the introduction of universal infant hepatitis B vaccination. The subjects were selected by stratified, multi-stage sampling. Vaccination history was obtained by immunization certificate (when available) or parent recall. Hepatitis B surface antigen (HBsAg) and antibodies to HBsAg (anti-HBs) and core antigen (anti-HBc) were detected by ELISA. Hepatitis B infection was defined as the presence of HBsAg and/or anti-HBc. The prevalence rates of HBsAg, anti-HBs and hepatitis B infection obtained in this survey were compared with the results of a survey conducted in 1992 (prior to universal vaccination).ResultsA total of 3738 children aged 1–14 years were included in the final analysis. A vaccination coverage rate of 93% was achieved in 2006. The prevalence rates of HBsAg and hepatitis B infection decreased from 8% and 46% in the 1992 survey to 1% and 4%, respectively, in the 2006 survey.ConclusionsUniversal hepatitis B vaccination in infants can result in a 90.47% reduction in hepatitis B infection in children aged 1–14 years

Performance evaluation of the 8-inch MCP-PMT for Jinping Neutrino Experiment

Jinping Neutrino Experiment plans to deploy a new type of 8-inch MCP-PMT with high photon detection efficiency for MeV-scale neutrino measurements. This work studies the performance of the MCP-PMTs, including the photon detection efficiency, the charge resolution of the single photoelectron, the transition time spread, single photoelectron response, rates of dark counts and after pulses. We find a long tail in the charge distribution, and combined with the high photon detection efficiency, the overall energy resolution sees substantial improvements. Those results will be provided as the inputs to detector simulation and design. Our results show that the new PMT satisfies all the requirements of the Jinping Neutrino Experiment

Performance of the 1-ton Prototype Neutrino Detector at CJPL-I

China Jinping Underground Laboratory (CJPL) provides an ideal site for solar, geo-, and supernova neutrino studies. With a prototype neutrino detector running since 2017, containing 1-ton liquid scintillator (LS), we tested its experimental hardware, performed the physics calibration, and measured its radioactive backgrounds, as an early stage of the Jinping Neutrino Experiment (JNE). We investigated the radon background and implemented the nitrogen sealing technology to control it. This paper presents the details of these studies and will serve as a key reference for the construction and optimization of the future large detector at JNE