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Taiwan is located in subtropical monsoon area and Pacific Ring of Fire. Both the rate of crustal uplift and annual rainfall are among the highest in the world. Earthquakes and heavy rainfall have led to massive landslides and debris flow. Frequent disasters and the high rate of surface erosion have caused drastic changes in river topography and catchment areas, and, consequently, have impacted the safety of human lives. To mitigate the losses, better simulation and prediction of landslides are critical. Existing landslide prediction research works employed terrain, geology, rainfall, earthquakes and human activities as landslide triggering factors in the predicting model. In addition to aforementioned environmental conditions, this study would like to explore the use of SAR differential interferometry (InSAR) information to help observe characteristics of the slope movement behavior, which is also an important factor. Factors are analyzed and quantified on the basis of slope units. To confirm the applicability of selected factors to landslide, factors are firstly analyzed with Spearman correlation, and then those with higher correlations are incorporated into the prediction model. Machine learning based techniques are then employed to establish the prediction model. The experiment result demonstrates that InSAR information can improve the accuracy by more than 5% in landslide prediction.

Observation of high energy and very high emission from Gamma Ray Bursts (GRBs) is crucial to study the gigantic explosion and the underline processes. With a large field-of-view and almost full duty cycle, the Water Cherenkov Detector Array (WCDA), a sub-array of the Large High Altitude Air Shower Observatory (LHAASO), is appropriate to monitor the very high energy emission from unpredictable transients such as GRBs. Nevertheless, the main issue for an extensive air shower array is the high energy threshold which limits the horizon of the detector. To address this issue a new trigger method is developed in this article to lower the energy threshold of WCDA for GRB observation. The proposed method significantly improves the detection efficiency of WCDA for gamma-rays around the GRB direction at 10-300 GeV. The sensitivity of the WCDA for GRB detection with the new trigger method is estimated. The achieved sensitivity of the quarter WCDA array above 10 GeV is comparable with that of Fermi-LAT. The data analysis process and corresponding fluence upper limit for GRB 190719C is presented as an example.

The main scientific goal of LHAASO-WCDA is to survey gamma-ray sources with energy from 100 GeV to 30 TeV. To observe high-energy shower events, especially to measure the energy spectrum of cosmic rays from 100 TeV to 10 PeV, a dynamic range extension system (WCDA++) is designed to use a 1.5-inch PMT with a dynamic range of four orders of magnitude for each cell in WCDA-1. The dynamic range is extended by using these PMTs to measure the effective charge density in the core region of air shower events, which is an important parameter for identifying the composition of primary particles. The system has been running for more than one year. In this paper, the details of the design and performance of WCDA++ are presented.

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 105 and 109 GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons—cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3–6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators. Observations of γ-rays with energies up to 1.4 PeV find that 12 sources in the Galaxy are PeVatrons, one of which is the Crab Nebula.

Phase mixing is a general mechanism of collisionless damping in magnetized plasmas. In a MHD model, the carrier of phase mixing is the Alfvén wave continuum, which is driven by the plasma inhomogeneity. In this work, we study the non-resonant conversion of a surface MHD eigenmode to the Alfvén continuum. It is shown that the finite-time-singularity of the phase of the surface mode can smear its periodic oscillation and induces the excitation of the local Alfvén waves. This type of mode conversion would enhance the collisionless dissipation of the surface eigenmode, i.e., accelerating its dissolution to the Alfvén continuum. The non-resonant mode conversion and damping mechanism explored here have potential applications to understand the physics of collisionless dissipation of various eigenmodes in magnetized plasmas.

The use of stochastic gradient algorithms for nonlinear optimization is of considerable interest, especially in the case of high dimensions. In this case, the choice of the step size is of key importance for the convergence rate. In this paper, we propose two new stochastic gradient algorithms that use an improved Barzilai–Borwein step size formula. Convergence analysis shows that these algorithms enable linear convergence in probability for strongly convex objective functions. Our computational experiments confirm that the proposed algorithms have better characteristics than two-point gradient algorithms and well-known stochastic gradient methods.

The COVID-19 pandemic is yet another reminder that the threat of infectious disease has never really gone away. As the cornerstone of preventing and controlling infectious diseases, effective surveillance and early warning are of great significance in understanding the outbreak and epidemic of specific infectious diseases and putting forward effective prevention and control measures. Therefore, we must continue strengthening the construction of infectious disease surveillance and early warning system. We reviewed the surveillance and early warning practices of infectious diseases in major countries and regions, then discussed the development direction in the field of surveillance and early warning of infectious diseases to provide the reference for strengthening the construction and capacity of infectious disease surveillance and early warning system in China.新型冠状病毒肺炎大流行再次警示人们，传染病威胁从未真正远去。有效的监测预警作为传染病防控的基石，对全面准确地认识特定传染病暴发流行、提出科学有效的防控策略和措施具有重要意义，因此须持续加强传染病监测预警体系建设。本文对世界主要国家和地区的传染病监测预警实践进行综述，探讨了传染病监测预警领域的发展方向，为进一步加强我国传染病监测预警体系建设与能力提升提供参考。.

Tracheal intubation under general anesthesia is more likely to aggravate the injury of the cervical spine and spinal cord. We aim to explore the effect of dexmedetomidine combined with intubating laryngeal mask airway (ILMA) on anesthesia and stress response in patients with a cervical spine injury.One hundred twenty patients were retrospectively allocated into the control group (midazolam + ILMA) and intervention group (dexmedetomidine + ILMA). Their hemodynamics at T1 (before anesthesia induction), T2 (1 minute after anesthesia induction), T3 (immediately after intubation), and T4 (1 min after successful intubation) were also compared.The heart rate (HR) and mean arterial pressure (MAP) of patients in the observation group were lower than those in the control group from T3 to T4 (both p = 0.000). Ramsay's score in the observation group was higher than the control group from T3 to T4 (both p= 0.000). No difference was observed in PaO2, PaCO2, and pH between the 2 groups. The level of serum cortisol (COR), plasma epinephrine (E), and norepinephrine (NE) in the observation group were lower than in the control group (p0.05) after induction.Dexmedetomidine combined with ILMA could improve the first intubation success rate and tolerance in patients with cervical spine injury by maintaining stable hemodynamics and reducing the stress response of patients.

This study explored whether clinical pharmacists can improve patients' medication compliance with the use of warfarin medication checklist and the correlation between them. A total of 147 inpatients discharged from Shanghai Tongren Hospital with warfarin from July 2018 to September 2019 were randomly divided into the control group and the intervention group by random number table, including 75 in the control group and 72 in the intervention group. There were no statistically significant differences in gender, age, marital status, drinking history, smoking history, department distribution, type of thromboembolic disease, comorbidity and combined medication between the two groups (本研究探索临床药师借助华法林用药清单是否能提高患者服药依从性以及两者之间的相关性。选取2018年7月至2019年9月上海市同仁医院出院带药华法林的147例住院患者，按照随机数字表法分为对照组和干预组，其中对照组75例，干预组72例。两组患者在性别、年龄、婚姻状况、饮酒史、吸烟史、科室分布、血栓栓塞性疾病种类、合并疾病及合并用药上，差异均无统计学意义（

The focal plane camera is the core component of the Wide Field-of-view Cherenkov/fluorescence Telescope Array (WFCTA) of the Large High-Altitude Air Shower Observatory (LHAASO). Because of the capability of working under moonlight without aging, silicon photomultipliers (SiPM) have been proven to be not only an alternative but also an improvement to conventional photomultiplier tubes (PMT) in this application. Eighteen SiPM-based cameras with square light funnels have been built for WFCTA. The telescopes have collected more than 100 million cosmic ray events and preliminary results indicate that these cameras are capable of working under moonlight. The characteristics of the light funnels and SiPMs pose challenges (e.g. dynamic range, dark count rate, assembly techniques). In this paper, we present the design features, manufacturing techniques and performances of these cameras. Finally, the test facilities, the test methods and results of SiPMs in the cameras are reported here., Comment: 45 pages, 21 figures, article

We report the discovery of a new unidentified extended $\gamma$-ray source in the Galactic plane named LHAASO J0341+5258 with a pre-trial significance of 8.2 standard deviations above 25 TeV. The best fit position is R.A.$=55.34^{\circ}\pm0.11^{\circ}$ and Dec$=52.97^{\circ}\pm0.07^{\circ}$. The angular size of LHAASO J0341+5258 is $0.29^\circ \pm 0.06^\circ_{stat} \pm0.02^\circ_{sys}$. The flux above 25 TeV is about $20\%$ of the flux of Crab Nebula. Although a power-law fit of the spectrum from 10 TeV to 200 TeV with the photon index $\alpha=2.98 \pm 0.19_{stat} \pm 0.02_{sys}$ is not excluded, the LHAASO data together with the flux upper limit at 10 GeV set by the Fermi LAT observation, indicate a noticeable steepening of an initially hard power-law spectrum %($\alpha \leq 1.75$) spectrum with a cutoff at $\approx 50$ TeV. We briefly discuss the origin of UHE gamma-rays. The lack of an energetic pulsar and a young SNR inside or in the vicinity of LHAASO J0341+5258 challenge, but do not exclude both the leptonic and hadronic scenarios of gamma-ray production., Comment: Accepted by APJL

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

The method of sequential modification of an objective function, which was earlier used for the classical transportation problem, is extended to the case of three indices. In the iterative process, the problem with three constraints and one binding variable is solved. Then, three independent problems with one constraint in which the coefficients for the binding variable are changed are considered. Using the suggested algorithm, a sequence of pseudosolutions with a monotonic growth of the objective function that converges to the optimum is constructed. The degeneracies are analyzed.

In this paper, we propose a training system for visual markers that provides the generation and subsequent recognition (under real-world conditions) of stylized images that contain information encoded by a sequence of bits. New types of neural network layers that make the recognition process tolerant to external noise are developed. The training process is based on the end-to-end principle, which enables automatic training for the intermediate stages of the model. The experimental results that demonstrate the performance of the system in encoding and decoding artificial markers are presented.

To evaluate the conversion of serum antibodies againstThe studies pertaining to serological tests of schistosomiasis japonica published from 1991 to 2020 were retrieved in electronic databases, including Chinese National Knowledge Infrastructure, WanFang Data, PubMed and ScienceDirect. Data were extracted from included studies. The publication bias was assessed with funnel plots using the software RevMan version 5.3, and the conversion of antibodies againstA total of 40 publications were included in the final meta-analysis, consisting of 33 Chinese publications and 7 English publications, and all immunological tests were performed with indirect hemagglutination test (IHA) and enzyme-linked immunosorbent assay (ELISA). Pooled analysis showed that the negative rates of serum anti-The negative rate of the serum anti

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

We report the discovery of a UHE gamma-ray source, LHAASO J2108+5157, by analyzing the LHAASO-KM2A data of 308.33 live days. Significant excess of gamma-ray induced showers is observed in both energy bands of 25-100 TeV and $\gt$100 TeV with 9.5 sigma and 8.5 sigma, respectively. This source is not significantly favored as an extensive source with the angular extension smaller than the point-spread function of KM2A. The measured energy spectrum from 20 to 200 TeV can be approximately described by a power-law function with an index of -2.83$\pm$ 0.18stat. A harder spectrum is demanded at lower energies considering the flux upper limit set by Fermi-LAT observations. The position of the gamma-ray emission is correlated with a giant molecular cloud, which favors a hadronic origin. No obvious counterparts have been found, deeper multiwavelength observations will help to shed new light on this intriguing UHE source., Comment: 12 pages, 7 figures, accepted by ApJL

The paper aimed to explore the role of micro ribonucleic acid (miR)-20a in regulating the proliferation and apoptosis of breast cancer cells.The expression of miR-20a in breast cancer cells was analyzed via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay. Cell Counting Kit-8 (CCK-8) assay, colony formation assay, and flow cytometry were employed to analyze the proliferation and apoptosis of cells. Thereafter, the target proteins of miR-20a were predicted using TargetScan, a website for miRNA target gene prediction, and the interaction between miR-20a and the target genes was detected through the Luciferase reporter gene assay, qRT-PCR assay, and Western blotting. Finally, the miR-20a inhibitor and target gene expression plasmids were co-transfected for rescue experiment to study whether the target genes participate in the inhibitory effect of miR-20a on the proliferation of breast cancer cells.It was found that the expression of miR-20a was upregulated in breast cancer cell lines. Silencing miR-20a expression inhibited the proliferation and promoted the apoptosis of breast cancer cell. Besides, it was demonstrated that late endosomal/lysosomal adaptor, mitogen-activated protein kinase (MAPK), and mammalian target of rapamycin (mTOR) activator 3 (LAMTOR3) were a direct target of miR-20a. The knockdown of LAMTOR3 expression repressed the influence of miR-20a on the proliferation of breast cancer cells.MiR-20a targets LAMTOR3 gene to regulate the mTOR signaling pathway, thereby suppressing the proliferation and facilitating the apoptosis of breast cancer cells. It suggests that miR-20a exerts a carcinogenic effect in breast cancer, which may be a potential target for the treatment of breast cancer.

To elucidate the relationship between microRNA-566 (miR-566) and prognosis in breast cancer (BC) and to clarify the influences of miR-566 and WNT6 in its locus region on BC progression.MiR-566 and WNT6 levels in 44 pairs of BC samples were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The influences of miR-566 on clinical features and prognosis in BC patients were analyzed. According to the differential expressions of miR-566 in the tested BC cell lines, MDA-MB-231 and MCF-7 cells were selected for generating miR-566 knockdown and overexpression models, respectively. Cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) and transwell assays were conducted to explore the role of miR-566 in BC cell functions. Besides, the regulatory interaction between miR-566 and its downstream gene WNT6 was assessed by performing Dual-Luciferase reporter assay. Finally, the co-regulation of miR-566 and WNT6 in BC cell functions was examined.MiR-566 was downregulated in BC tissues. BC patients with a low expression level of miR-566 were prone to suffering a large tumor size, advanced tumor grade, high incidence of lymphatic metastasis and poor prognosis. Overexpression of miR-566 weakened proliferative and migratory abilities in MCF-7 cells, whereas knockdown of miR-566 produced the opposite results in MDA-MB-231 cells. WNT6 was the target gene binding to miR-566, and they displayed a negative expression correlation in BC tissues. Regulatory effects of miR-566 on BC progression could be reversed by WNT6.MiR-566 is closely related to tumor size, tumor grade, lymphatic metastasis and prognosis in BC. It protects the malignant progression of BC by negatively regulating WNT6.

Shortcomings have been inherited in the traditional influenza early warning system, often expressed through the scope, accuracy on prediction and real-time performance of the monitor related programs. With the new round of scientific and technological revolution and the increasingly maturity of modern information system, related technology on influenza early warning has become the focus of research in this field, based on big data analysis technology. Using the traditional influenza surveillance and early warning system as reference, this paper summarizes the progress of influenza early warning research, based on the Internet, influencing factors, time and space trends, and risk assessment传统流感预警体系在监测范围、预测准确性和实时性等方面仍存在不足。随着新一轮科技革命的兴起，现代信息技术日趋成熟，以大数据分析为基础的流感预警技术已经成为研究焦点。本文以传统流感监测预警体系作为参照，从互联网、影响因素、时空趋势、风险评估4个角度总结基于大数据的流感预警研究进展，综述大数据在流感预警中的优势、不足及未来发展的趋势。.

To quantitatively evaluate the diagnostic value of variable-temperature and isothermal nucleic acid amplification techniques in the detection of schistosomiasis japonica using a meta-analysis.The publications pertaining to the nucleic acid detection of schistosomiasis japonica were searched in electronic databases, including Chinese National Knowledge Infrastructure (CNKI), Wanfang Data, PubMed and ScienceDirect, and the compilations and proceedings of schistosomiasis were manually searched. In addition, the citations of publications associated with the nucleic acid detection of schistosomiasis japonica were traced using a document tracing method. The retrieved literatures were screened according to the inclusion and exclusion criteria, and data were extracted from the included literatures. The quality of the included literatures was assessed using the software RevMan version 5.3, and a meta-analysis was performed using the software MetaDiSc version 1.4.A total of 19 publications covering 24 groups of studies were enrolled, including 5 Chinese publications and 14 English publications. There were 17 groups of studies reporting the comparison between the variable-temperature nucleic acid amplification technique and the golden standard, and 7 groups of studies showing the comparison between the isothermal nucleic acid amplification technique and the golden standard. Assessment of the literature quality indicated a minor overall bias of the included literatures, and the Deek funnel plot showed a possible publication bias in the documents reports variable-temperature nucleic acid amplification techniques. There was a heterogeneity caused by non-threshold effect among the studies associated with the variable-temperature amplification technique, and the random effects model was therefore used to combine the effects. The pooled sensitivity and specificity of the variable-temperature amplification technique were 0.81 (0.79 to 0.83) and 0.73 (0.71 to 0.74) for the diagnosis of schistosomiasis japonica, and area under the SROC curve was 0.944 3. There was no heterogeneity among the studies associated with the isothermal amplification technique, and the fixed effects model was therefore used to combine the effects. The pooled sensitivity and specificity of the isothermal amplification technique were 0.96 (0.94 to 0.98) and 0.95 (0.94 to 0.97) for the diagnosis of schistosomiasis japonica, and area under the SROC curve was 0.989 9.Both variable-temperature and isothermal nucleic acid amplification techniques have a high efficiency for the diagnosis of schistosomiasis japonica, and the isothermal amplification technique shows a relatively higher accuracy than the variable-temperature amplification technique.

In recent years, men who have sex with men (MSM) constitute a major group of HIV transmission in China. High primary drug-resistance (PDR) rate in MSM also represents a serious challenge for the Chinese antiretroviral therapy (ART) program. To assess the efficiency of ART in controlling HIV/AIDS infection among MSM, we developed a compartmental model for the annually reported HIV/AIDS MSM from 2007 to 2019 in the Zhejiang Province of China. R0 was 2.3946 (95% CI (2.2961–2.4881)). We predict that 90% of diagnosed HIV/AIDS individuals will have received treatment till 2020, while the proportion of the diagnosed remains as low as 40%. Even when the proportion of the diagnosed reaches 90%, R0 is still larger than the level of AIDS epidemic elimination. ART can effectively control the spread of HIV, even in the presence of drug resistance. The 90-90-90 strategy alone may not eliminate the HIV epidemic in Chinese MSM. Behavioural and biologic interventions are the most effective interventions to control the HIV/AIDS epidemic among MSM.

The main scientific goal of the LHAASO WFCTA experiment is to measure the cosmic ray energy spectra and composition from 10 TeV to 1 EeV. Cherenkov photons in the extensive air shower measured by the SiPM camera of Cherenkov telescopes can be used to reconstruct the cosmic ray energy. The absolute calibration of the camera is a crucial step to achieve the accurate measurement of the cosmic ray energy spectrum. A multi-wavelength cylindrical illuminator based on LEDs is developed and mounted inside the telescope to calibrate and monitor the camera, and the illuminator’s stability is better than 0.5% under the temperature variation from -26 to 26 ° C. A portable probe with a single photoelectron resolution of 21.6% is developed. After calibration by National Institute of Metrology, China (NIM), the probe is taken to the LHAASO site to measure the absolute photon density of the cylindrical illuminator inside the telescope. Based on the illuminator with known photon density, the photon conversion factor of the camera can be calibrated, and the overall calibration uncertainty is less than 2.6%.

A decomposition method based on the sequential modification of the optimality criterion is used for solving the classical three-index transportation problem. The method consists of a sequence of solutions of local problems with three constraints. A monotonic (in the optimality criterion) process that converges to the solution of the original problem is constructed. The solutions of the transportation problem with a linear and quadratic objective function are considered and the numerical results are presented.

The large high altitude air shower observatory (LHAASO) is being constructed at 4400 m a.s.l. in Daocheng, Sichuan Province, aiming to reveal the secrets of cosmic rays origin. And it has the largest surface muon detector array in the world. Due to the needs of calibration and construction of muon detector, we developed a water optical attenuation measurement device using an 8 m long water tank. The results are presented for filtered water at wavelength of 405 nm, which proves this apparatus can reach an accuracy of about 20% at 100 m. This apparatus has not only a high precision measurement of water attenuation length up to 100 m but is also very convenient to be used, which is crucial for water optical properties study during LHAASO detector construction.

A problem of optimizing a matrix sparse in the joint Frobenius-Schatten norm is considered. The least rows are proposed to be truncated according to the lower bound to fight the ill-conditionality of the matrix. Truncation not only helps avoid incorrect termination of the algorithm but it also reduces the computational complexity. Convergence analysis ensures that a truncation algorithm finds an approximate solution to the problem. The numerical experiments show the advantage of the truncation method over the previous algorithm.

In recent decades, the theory of hypergraphs has been applied to real-life problems. The tools of hypergraph theory can be used for modeling networks, biological networks, data structures, scheduling processes and computations, and many other systems with complex relationships between the entities. From the theoretical point of view, hypergraphs make it possible to generalize certain theorems in graph theory or even replace a number of theorems on graphs by one theorem on hypergraphs. However, the majority of the potentials in the development of hypergraph theory are blocked due to inconsistencies in the basic terms. It is proposed to make up a list of basic terms related to hypergraph theory, which can help standardize this theory.

The Belt and Road Initiative (BRI) was proposed by China, aiming to promote multilateral cooperation with the world. However, existing studies has shown the external water dependency of the Initiative on the rest economies (Non-BRI), which may enhance the vulnerability of production activities in BRI. To understand the vulnerability of the BRI to water scarcity in Non-BRI, this study evaluates the impacts of water scarcity in Non-BRI on BRI, by using a multi-regional input-output model. Results show that among all BRI, China, South Korea, Russia and India were most vulnerable to water scarcity in Non-BRI, especially Spain, Sudan, the United States and Australia. Water scarcity to Agriculture sectors of Non-BRI exerted widespread influences on the BRI trade system. This study analyses the vulnerability of the BRI induced by water dependency on Non-BRI by identifying critical nations and sectors, and informs stokeholds of the BRI to pay attentions on the water scarcity of their upstream to mitigate the supply chain risk, and thus achieve sustainable development.

Apple stem grooving virus (ASGV) occurs worldwide on apple (Malus pumila), pear (Pyrus pyrifolia), citrus (Citrus reticulata) and lily (Lilium brownii). Its incidence in pears trees from twelve provinces in China was determined using reverse transcription polymerase chain reaction. Overall, 84% of trees were infected with ASGV. Partial sequences of coat protein gene in isolates from pear had 85–100% nucleotide (nt) identities and 91–100% amino acid (aa) identities. The aa identity in the variable region of the movement protein ranged from 49 to 100%. The complete genome of one ASGV isolate (HH) was determined. The isolate showed an overall nt identity of 80–91% to fourteen previously reported isolates from a range of hosts; the highest identity to isolate ASGV-CHN infecting apple in China and the lowest identity to an isolate ASGV-P infecting pear in South Korea. This is the first comprehensive study on the incidence and molecular divergence of ASGV in pear.

Health care workers have higher risk of influenza infection because of their occupational exposure to infected patients. Infection of the health care workers may not only result in the increasing risk of the nosocomial infection and family transmission, but also disrupt the health services due to absence from work. Health care workers were recommended as a priority group of influenza vaccinationin more than 40 countries and regions in the world. In recent years, domestic surveys show that the influenza vaccine coverage among health care workers was low. This paper outlines the current status and related policies of influenza vaccination among health care workers in China and global. Additionally, we analyzed and discussed the proper immunization strategy of influenza vaccine for medical staff in China.医务人员由于日常工作暴露，罹患流感的风险更高。同时医务人员感染流感病毒可增加院内和家庭传播的风险，由于疾病导致的缺勤还会影响医疗体系的正常运转。全球有40多个国家和地区均将医务人员纳入流感疫苗接种的优先人群。国内调查数据显示医务人员流感疫苗接种率普遍不高。本文主要对国内外流感疫苗的接种政策和现状进行概述，分析探讨符合我国实际的医务人员流感疫苗免疫策略。.

Let $s$ and $t$ be two coprime integers. Bessenrodt and Olsson obtained the number of $(\overline{s},\overline{t})$-cores for odd $s$ and odd $t$ by establishing a bijection between the lattice paths in $(s,t)$ Yin-Yang diagram and $(\overline{s},\overline{t})$-cores. In this paper, motivated by their results, we extend the definition of Yin-Yang diagram and the bijection to all possible coprime pairs $(s,t)$, then obtain that the number of $(\overline{s},\overline{t})$-cores is $\binom{\lfloor s/2 \rfloor + \lfloor t/2 \rfloor}{\lfloor s/2 \rfloor}$. Furthermore, based on the identities of Chen-Huang-Wang, we determine the average size of an $(\overline{s},\overline{t})$-core depending on the parity of $s$, which is $(s-1) (t-1) (s+t-2)/48$ if $s$ and $t$ are both odd, or $(t-1) (s^2+st-3s+2t+2)/48$ if $s$ is even and $t$ is odd.

In recent years, the reported incidence of brucellosis continued to rise and the epidemic spread kept, which has become an important public health problem in China. Continuous improvement of the surveillance system is important for effective control and prevention of brucellosis. This article systematically summarizes the construction and development of the brucellosis surveillance system, analyzes the main characteristics of the current brucellosis surveillance system and evaluates the surveillance system in China, and it also put forward suggestions for the further improvement of the surveillance system to meet the new requirement for brucellosis surveillance, control and prevention.近几年布鲁氏菌病（布病）报告发病水平持续上升、流行范围不断蔓延，已成为我国重要的公共卫生问题。持续改进布病的监测系统对于有效开展布病防控意义重大。本文系统综述了我国布病监测系统的建设与发展，对当前布病监测系统的主要特点进行了分析，对监测系统的评价进行了综述，并为进一步改进监测系统，以适应其新的监测防控需求提出建议。.

The Muon detector (MD) of LHAASO-KM2A (Large High-Altitude Air Shower Observatory 1km2 Array) [1] is a water Cherenkov detector with an effective area of ~36 m2. The 2.5 m thick overburden soil is used as a shield to prevent low energy electromagnetic particles from reaching water. Each MD must be well tested before the covering process of the thick soil. In this case, the on-site test system is designed and manufactured, consisting of a telescope and a data acquisition system. The telescope is a combination of two vertically placed scintillator detectors covered by 4cm thick lead each. Charge resolution and time resolution are estimated by analysing the test data. In addition, waveforms of the MD signal are recorded each second, which will serve to evaluate the water quality of MD.