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We present the results of the neutron star X-ray binary system Cen X-3 performed by $Insight$-HXMT with two observations during 2017 and 2018. During these two observations, the source reached a X-ray luminosity of $\sim 10^{38}$ erg s$^{-1}$ from 2 -- 105 keV. The analysis of the broadband X-ray spectrum reports the presence of two cyclotron resonance scattering features (CRSFs) with the fundamental line at $\sim$ 28 keV and the harmonic line at $\sim 47 $ keV. The multiple lines exist by fittings with different continuum models, like the absorbed NPEX model and a power-law with high energy exponential cutoff model. This is the first time that both fundamental and harmonic lines are detected in Cen X-3. We also show evidence of two cyclotron lines in the phase-resolved spectrum of Cen X-3. The CRSF and continuum spectral parameters show evolution with the pulse profile, and the two line centroid energy ratio does not change significantly and locates in a narrow value range of $1.6-1.7$ over the pulse phase. The implications of the discovering two cyclotron absorption features and phase-resolved spectral properties are discussed., Comment: 8 pages, MNRAS, 2023, 519, 5402-5409

For the difficulty of boundary-fitting in region-based algorithms, a region adaptive adjustment strategy based on information entropy is proposed for remote sensing image segmentation. Considering the characteristics of imperfect blocks that cover two homogeneous regions, a selection factor constructed by the spectral coefficient of variation and the information entropy of prior probability representing neighborhood constraint is designed to find the imperfect blocks. Then, the selected imperfect block is split into four equal parts, and new blocks enjoy the same membership as the original block. The model parameters are updated based on the current tessellation. If the fuzzy clustering objective function decrease, the split operation is certainly accepted, otherwise, it will be accepted with a certain probability to avoid local optimum. Finally, the experiments on simulated and multi-spectral remote sensing images show that the proposed strategy can accurately locate the imperfect blocks and effectively fit the boundary of homogeneous regions.

Food safety in China has been significantly improved since the melamine crisis in 2008 and the promulgation of the first Food Safety Law in 2009. However, food safety is a long standing issue in China due to the backward productive structure of agriculture and food business. In order to further improve the food safety in China, it is critical to reach a consensus on the leading edge concept of food safety and the identification of priority areas based on the concept. The leading edge concept of food safety aims to prevent potential issues and deal with current issues based on the risk, i.e. risk-based approach, as opposed to the concept based on the hazard, i.e. hazard-based approach. Practice is to determine the key problems that need to be solved first according to the concept. This paper expounds the different food safety management strategies and measures caused by the two concepts, and lists several key food safety problems (importance and solutions) determined according to the concept of "risk-based". These examples include foodborne diseases caused by pathogenic microorganisms, antimicrobial resistance, food allergen control, risk assessment of multiple chemical hazards exposure and alternative methods in food toxicology.中国的食品安全状况，自2008年三聚氰胺事件和2009年发布第一版《食品安全法》以来，取得了长足的进步。然而食品安全是一个长久的话题，因为中国农业和食品业的生产结构落后、地域辽阔、发展不平衡。为了将中国食品安全水平进一步提升，更上一层楼，必须就前沿发展达成共识，包括理念和实践。当前，食品安全的前沿理念应是“以风险为基础”来预防和应对潜在的和已发生的食品安全问题，而与之相对应的则是“以危害为基础”的理念。而实践则是根据理念确定需要优先解决的重点问题。文章阐述了两种理念导致的不同食品安全管理策略和措施，并列举了几个根据“以风险为基础”理念确定的重点食品安全问题（重要性、解决方案）。这些例子包括：致病性微生物引起的食源性疾病；抗生素的耐药性；食物过敏原的管控；化学性危害混合暴露的风险评估；以及毒理学替代方法。.

To effectively describe the uncertainty of remote sensing image segmentation, a novel region-based algorithm using fuzzy clustering and Kullback-Leibler (KL) distance is proposed. By regular tessellation, the image domain is completely divided into several sub-blocks to overcome the complex noise existed in high-resolution remote sensing images. Taking the blocks as the basic processing units, KL divergence is used to model the distance between blocks and clusters, which enables the model to describe the uncertainty of the non-similarity relationship. Besides, based on the theory of Markov Random Field (MRF), the regionalized KL entropy regularization term is established and added to the objective function to further consider the spatial constraints. Finally, the optimal segmentation results are obtained by estimating the parameters. The experiments carried out on different kinds of remote sensing images by comparing algorithms fully demonstrate the performance of the proposed algorithm.

Physical inactivity is responsible for 6% of global deaths, and it is an independent risk factor for cardiovascular diseases, cancer, chronic respiratory diseases and diabetes. The general lack of physical activity has become an important global public health problem. Active and adequate physical activity is an important public health measure to ensure health throughout the life cycle. Under the guidance of the Bureau for Disease Prevention and Control of the National Health Commission, the Chinese Center for Disease Control and Prevention and the Institute of Sports Science of the General Administration of Sport of China jointly organize experts to complete the compilation of The Physical Activity Guidelines for Chinese (2021) based on a large number of domestic and foreign scientific data. We look forward to the release and implementation of the guidelines, which will play an important role in scientifically guiding the physical activity of all types of people in China, reducing the rate of physical inactivity, and promoting the early realization of the goal of the Healthy China Action.身体活动不足造成全球6%的死亡，而且是心血管疾病、癌症、慢性呼吸系统疾病和糖尿病的独立危险因素。人群身体活动普遍不足已成为全球重要的公共卫生问题。积极和充足的身体活动是保证全生命周期健康的重要公共卫生措施。在国家卫生健康委员会疾病预防控制局指导下，中国疾病预防控制中心与国家体育总局体育科学研究所共同牵头，组织专家在参考了大量国内外科学资料的基础上，完成了《中国人群身体活动指南（2021）》的编写。我们期待指南的发布与实施，能为科学指导中国各类人群身体活动、降低身体活动不足率，为促进健康中国行动目标早日实现发挥重要作用。.

In this paper, the impacts of external pressure on structural stability, elasticity, thermodynamics and relevant electronic structures of L12-type Ni3X (X=Al, Ti, V, Nb) phases were investigated using the first-principles methods. The lattice parameters(a,b,c) and volume(V) of the Ni3X phases decrease with increasing pressure. however, the elastic constants(Cij ), bulk modulus(B), shear modulus(G), and Young's modulus (E) increase. The calculated elastic constants indicate that the mechanical stability and ductility of Ni3X phases enhance with increasing pressure. The mechanical anisotropy of Ni3X phases are enhanced by the raised pressure. Electronic analysis shows that increase pressure makes Ni-d-orbital and X(X=Al, Ti, V, Nb) -d-orbital hybridization stronger and electron transfer increases. The sequence in regard to electron aggregation strength is Ni3Ti>Ni3Nb>Ni3V>Ni3Al. It is more directly reflected in the charge density difference maps. This is consistent with the analysis results of the enthalpy of formation(ΔH) and Debye temperature (ΘD).

In this paper, the effect of pressure on the structural stability, elasticity, thermodynamics, and associated electronic structure of L1

Phase stability, elasticity, hardness and relevant electronic structures of M nB m (M = Ni, Cr, Mo, W, n = 23,5,3,1, m = 6,3,2,1) binary borides have been investigated by first-principles calculati...

The CaO-ZnO-B2O3-P2O5 glass-ceramics with various amounts of TiO2 as crystallized agent were prepared by solid-state method. The effects of TiO2 addition on the crystallization kinetics, microstructure and dielectric properties were systematically evaluated. Adding moderate content of TiO2 can obviously promote crystallization and improve the microstructure of the glass-ceramics, due to the reduction of crystallization activation energy. It is also found that with the content of TiO2 increasing, the dielectric constant (er) and quality factor (Q×f) of the glass-ceramics firstly increase and then decrease, however, temperature coefficient of resonance frequency (τf) moves to positive value. Meanwhile, the sintering temperature also has a direct influence on the dielectric properties of the glass-ceramics. The glass-ceramic with 0.5 wt% TiO2 sintered at 760 °C for 2 h possesses good dielectric properties of er = 4.75, Q×f= 23500 GHz, τf = −17 ppm/°C, which indicates that the as-prepared glass-ceramic is a promising candidate for low temperature co-firing ceramics.

Back pain resulted from spine disorders reaches 60–80% prevalence in humans, which seriously influences life quality and retards economic production. Conventional electrical pain relief therapy uses radiofrequency to generate a high temperature of 70–85 °C on the electrode tip to destroy the neural transmission and stop the pain. However, due to the larger area of stimulation, eliciting significant side effects, such as paralysis, contraction, and a slightly uncomfortable feeling, our study aimed to design a tiny and stretchable neural stimulatory electrode that could be precisely anchored adjacent to the dorsal root ganglion which needs therapy and properly interfere with the sensory neural transmission. We also designed a subcutaneously implantable wireless power transmission (WPT) device to drive the neural stimulatory electrode. Through the study, we elaborated the design concept and clinical problems, and achieved: (1) the architecture design and simulation of the transdermal wireless power transferred device, (2) a wrap-able pulsed radiofrequency (PRF) stimulatory electrode, (3) an insulation packaging design of the titanium protection box. The feasibility study and hands-on prototype were also carried out.

Microelectrodes for pain management, neural prosthesis or assistances have a huge medical demand, such as the application of pain management chip or retinal prosthesis addressed on age-related macular degeneration (AMD) and the retinitis pigmentosa (RP). Due to lifelong implanted in human body and direct adhesion of neural tissues, the electrodes and associated insulation materials should possess an ideal bio-compatibility, including non-cytotoxicity and no safety concern elicited by immune responses. Our goal intended to develop retinal prosthesis, an electrical circuit chip used for assisting neural electrons transmission on retina and ameliorating the retinal disability. Therefore, based on the ISO 10993 guidance for implantable medical devices, the electrode prosthesis with insulation material has to conduct bio-compatibility assessment including cytotoxicity, hemolysis, (skin) irritation and pathological implantation examinations. In this study, we manufactured inter-digitated electrode (IDE) chips mimic the electrode prosthesis through photolithography. The titanium and platinum composites were deposited onto a silicon wafer to prepare an electric circuit to mimic the electrode used in retinal prosthesis manufacture, which further be encapsulated to examine the bio-compatibility in compliance with ISO 10993 and ASTM guidance specifically for implantable medical devices. Parylene-C, polyimide and silicon carbide were selected as materials for electrode encapsulation in comparison. Our data revealed parylene-C coating showed a significant excellence on bio-insulation and bio-compatibility specifically addressed on implantable neuron stimulatory devices and provided an economic procedure to package the electrode prosthesis. Therefore, parylene C encapsulation should serve as a consideration for future application on retinal prosthesis manufacture and examination.

Depletion of islet β cells plays a crucial role in the onset of diabetes mellitus. Cell autophagy, as a self-healing process, contributes to maintaining metabolic homeostasis and can protect islet β cells from apoptosis upon starvation or high glucose stress. However, the underlying regulatory network of the autophagic process in islet β cells has not been fully explored.Murine β-TC3 cells treated with different concentrations of glucose, and wild-type or the Ser484 mutant human cell division cycle gene 14A (hCDC14A) was transfected. Cell viability, proliferation and autophagy as well as islet secretion were studied. The mTOR and AMPK signaling pathways were investigated by western blots. Zipper-interacting protein kinase was studied using mass spectrometry and immunoprecipitation.Overexpression of wild-type hCDC14A, but not the Ser484 mutant hCDC14A, promoted cell viability, proliferation and autophagy accompanied by enhanced islet secretion and reduced cell apoptosis via mTOR pathway inhibition as well AMPK pathway activation in β-TC3 cells and vice versa. Furthermore, Zipper-interacting protein kinase (ZIPK), also known as DAPK3, was found to interact with hCDC14A primarily for Ser484 phosphorylation, and ZIPK knockdown could affect the phosphorylation of hCDC14A and weaken cell death or cell cycle modulation.Taken together, our results may provide new insight into the role of hCDC14A in the autophagy of islet β cells and suggest the potential therapeutic value of hCDC14A phosphorylation in the prevention and treatment of diabetes.

Objective To identify the species of common necrophagous flies in Fujian Province by gene fragment sequences of mitochondrial cytochrome c oxidase subunit Ⅰ （COⅠ） and 16S ribosomal deoxyribonucleic acid （16S rDNA）, and to explore the identification efficacy of these two molecular markers. Methods In total 22 common necrophagous flies were collected from the death scenes in 9 different regions in Fujian Province and DNA was extracted from the flies after morphological identification. The gene fragments of COⅠ and 16S rDNA were amplified and sequenced. All the sequences were uploaded to GeneBank and BLAST and MEGA 10.0 software were used to perform sequence alignment, homology analysis and intraspecific and interspecific genetic distance analysis. The phylogenetic trees of DNA fragment sequences of COⅠ and 16S rDNA of common necrophagous flies in Fujian Province were established by unweighted pair-group method with arithmetic means （UPGMA）, respectively. Results The flies were classified into 6 species, 5 genera and 3 families by morphological identification. The results of gene sequence analysis showed that the average number of interspecific and intraspecific genetic distance of 16S rDNA ranged from 1.8% to 8.9% and 0.0% to 2.4%, respectively. The average number of interspecific and intraspecific genetic distance of COⅠ ranged from 7.2% to 13.6% and 0.0% to 6.3%, respectively. Conclusion The gene sequences of COⅠ and 16S rDNA can accurately identify the species of different necrophagous flies, and 16S rDNA showed higher value in species identification of common calliphoridae necrophagous flies in Fujian Province.福建省常见尸食性蝇类的COⅠ及16S rDNA序列鉴定.目的 利用线粒体细胞色素c氧化酶亚基Ⅰ（cytochrome c oxidase subunit Ⅰ，COⅠ）以及16S核糖体脱氧核糖核酸（ribosomal deoxyribonucleic acid，rDNA）基因片段序列对福建省常见尸食性蝇类种属进行分子鉴定，探讨两种遗传标记的鉴别效力。 方法 收集福建9个地区案件现场捕获的常见尸食性蝇类样本22只，经形态学鉴定后提取DNA，扩增COⅠ及16S rDNA基因片段，测序后上传GeneBank数据库，使用BLAST、MEGA 10.0软件进行序列比对、同源性分析以及种内和种间遗传距离分析，并采用非加权组平均法（unweighted pair-group method with arithmetic means，UPGMA）分别构建福建省常见尸食性蝇类COⅠ及16S rDNA基因片段序列的系统发育树。 结果 经形态学鉴定，共收集到3科5属6种常见尸食性蝇类。基因序列分析结果显示，16S rDNA基因片段序列的种间遗传距离均数为1.8%~8.9%，种内遗传距离均数为0.0%~2.4%；COⅠ基因片段序列的种间遗传距离均数为7.2%~13.6%，种内遗传距离均数为0.0%~6.3%。 结论 COⅠ和16S rDNA基因片段序列均能够对不同蝇种的种属进行鉴别，16S rDNA对于福建省常见丽蝇科尸食性蝇类的种属鉴别价值更高。.法医病理学；法医遗传学；法医昆虫学；尸食性蝇类；聚类分析；细胞色素c氧化酶亚基Ⅰ；16S核糖体脱氧核糖核酸；福建.