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Ya-Song Luan,1 Gao Zhan-ling,1 Li Mi,1 Liu Ying,2 Bai Lan,1 Li Tong1 1Department of Nursing Science, Shandong Traditional Chinese Medicine College, YanTai, People’s Republic of China; 2Department of Neurosurgery, YanTai Affiliated Hospital of Binzhou Medical College, YanTai, People’s Republic of ChinaCorrespondence: Ya-Song Luan, Department of Nursing Science, Shandong Traditional Chinese Medicine College, YanTai, People’s Republic of China, Email 1067880955@qq.comBackground: Few individuals have focused on the experience of students during social events, especially among college students with social anxiety disorder. This study aimed to explore the anxiety experience among college students with social anxiety disorder in social situations.Methods: This qualitative interpretive study was conducted on college students who were diagnosed with social anxiety disorder (SAD) and recruited from two colleges in Heilongjiang Province, China. A total of 7 participants were selected by purposive sampling with maximum variability. Data were collected through semistructured individual interviews, and data analysis was performed by using Colaizzi’s 7-step analysis method.Results: The findings from the analysis of the interviews were classified into 4 themes and several main categories, including distorted self-awareness (3 main categories), fear of negative reaction from others (2 main categories), adverse reaction of body and mind (4 main categories) and strong desire to seek treatment.Conclusion: In our study, we sought to understand the anxiety experience among college students with social anxiety disorder in social situations. The study results provide a reference for psychologists and clinical medical staff and establish a scientific basis for the prevention and intervention of social anxiety disorder.Keywords: social anxiety disorder, qualitative study, anxiety experience

This paper proposes a linear categorical random coefficient model, in which the random coefficients follow parametric categorical distributions. The distributional parameters are identified based on a linear recurrence structure of moments of the random coefficients. A Generalized Method of Moments estimation procedure is proposed also employed by Peter Schmidt and his coauthors to address heterogeneity in time effects in panel data models. Using Monte Carlo simulations, we find that moments of the random coefficients can be estimated reasonably accurately, but large samples are required for estimation of the parameters of the underlying categorical distribution. The utility of the proposed estimator is illustrated by estimating the distribution of returns to education in the U.S. by gender and educational levels. We find that rising heterogeneity between educational groups is mainly due to the increasing returns to education for those with postsecondary education, whereas within group heterogeneity has been rising mostly in the case of individuals with high school or less education.

Traditional approaches to the design of multi-agent navigation algorithms consider the environment as a fixed constraint, despite the influence of spatial constraints on agents' performance. Yet hand-designing conducive environment layouts is inefficient and potentially expensive. The goal of this paper is to consider the environment as a decision variable in a system-level optimization problem, where both agent performance and environment cost are incorporated. Towards this end, we propose novel problems of unprioritized and prioritized environment optimization, where the former considers agents unbiasedly and the latter accounts for agent priorities. We show, through formal proofs, under which conditions the environment can change while guaranteeing completeness (i.e., all agents reach goals), and analyze the role of agent priorities in the environment optimization. We proceed to impose real-world constraints on the environment optimization and formulate it mathematically as a constrained stochastic optimization problem. Since the relation between agents, environment and performance is challenging to model, we leverage reinforcement learning to develop a model-free solution and a primal-dual mechanism to handle constraints. Distinct information processing architectures are integrated for various implementation scenarios, including online/offline optimization and discrete/continuous environment. Numerical results corroborate the theory and demonstrate the validity and adaptability of our approach., Comment: arXiv admin note: substantial text overlap with arXiv:2209.11279

Additional file 1. Supplemental Data.

Additional file 2. Supplementary tables.

Nocardiosis is a rare but life-threatening infection particularly affecting immuno-compromised hosts, causing localized or systemic suppurative disease usually in human beings. Nocardia species, as the pathogen of nocardiosis, are difficult to differentiate because of their complex colony morphological features. In this study, we describe two patients who had been misdiagnosed for a long time infected with Nocardia cyriacigeorgica with completely different morphology were accurately diagnosed. Single colonies were analyzed by Gram staining, acid-fast stain, mass spectrometry and whole genome resequencing (WGRS). These two bacterial, strains L5.53 and L5.54, were found to be Gram-negative and acid-fast-weak positive. Blood sample culturing of strain L5.53 yielded white colonies, which were like a layer of hoarfrost, while colonies of L5.54 were yellow, rough, slightly convex. The two strains were identified as Nocardia sp. by mass spectrometry, and WGRS accurately determined them as N. cyriacigeorgica. After medical treatment, one patient was cured and the other was still receiving treatment in the hospital. It can be seen that Nocardia sp. cannot be accurately classified and identified only by phenotypic tests such as bacterial morphological differences, so it is necessary to identify Nocardia spp. with phenotypic tests in combination with other molecular biology technologies, such as WGRS.

BackgroundPerimenopausal depression (PMD) is characterized by affective symptoms as well as menopause-specific somatic complaints and has attracted increasing attention over the past few decades. Using a bibliometric tool, this study aims to evaluate the origin, current hotspots, and research trends on PMD.MethodsArticles with research on PMD were retrieved from Web of Science Core Collection (WoSCC). We used the bibliometric method to analyze publication years, journals, countries, institutions, authors, research hotspots, and trends. We plotted the reference co-citation network and used keywords to analyze the research hotspots and trends.ResultsA total of 209 publications related to PMD were identified from WoSCC on May 8, 2022. The number of publications concerning PMD every year shows an upward trend. Further analysis indicated that 209 articles were contributed by 45 countries, 288 institutions, and 501 authors. The United States contributed the most significant number of publications, followed by China. Harvard University is the core institution of PMD research, and Cohen’s work has had an important impact on another research. The occurrence and pathological mechanisms of depression during the menopausal transition from the knowledge base of PMD. All of them belong to the category of gynecology and psychosis, which reflects the focus of the research topics. Major depression, postmenopausal women, symptoms like hot flashes, and prevalence and risk factors are research hotspots in the PMD field. The frontiers in PMD field that will impact future research are anxiety, meta-analysis, association, and Beck Depression Inventory-II (BDI-II).ConclusionThese findings provide us with the core countries, institutions, and authors in PMD research and point out the direction of attention in this field. The current research focuses on depression, postmenopausal women, hot flashes, and other symptoms, as well as the prevalence and risk factors. The frontiers will be anxiety, meta-analysis, related factors, and depression assessment in future research.

Perimenopause is a period of susceptibility to depression among women. With societal development, perimenopausal women are under increasing pressure from all aspects. Based on these two reasons, the risk of depression in perimenopausal women was significantly higher than that in other stages and showed a gradual upward trend. However, the specific pathogenesis of permenopausal depressive disorder is unclear, there are no preferred drugs in the clinic. This study will use Bayesian network meta-analysis to evaluate the existing medicines in different detection indicators to provide the most appropriate treatment for patients with various degrees.

Adenosine (ADO) is an extracellular signaling molecule generated locally under conditions that produce ischemia, hypoxia, or inflammation. It is involved in modulating a range of physiological functions throughout the brain and periphery through the membrane-bound G protein-coupled receptors, called adenosine receptors (ARs) A1AR, A2AAR, A2BAR, and A3AR. These are therefore important targets for neurological, cardiovascular, inflammatory, and autoimmune diseases and are the subject of drug development directed toward the cyclic adenosine monophosphate and other signaling pathways. Initially using public data for A1AR agonists we generated and validated a Bayesian machine learning model (Receiver Operator Characteristic of 0.87) that we used to identify molecules for testing. Three selected molecules, crisaborole, febuxostat and paroxetine, showed initial activity in vitro using the HEK293 A1AR Nomad cell line. However, radioligand binding, β-arrestin assay and calcium influx assay did not confirm this A1AR activity. Nevertheless, several other AR activities were identified. Febuxostat and paroxetine both inhibited orthosteric radioligand binding in the µM range for A2AAR and A3AR. In HEK293 cells expressing the human A2AAR, stimulation of cAMP was observed for crisaborole (EC50 2.8 µM) and paroxetine (EC50 14 µM), but not for febuxostat. Crisaborole also increased cAMP accumulation in A2BAR-expressing HEK293 cells, but it was weaker than at the A2AAR. At the human A3AR, paroxetine did not show any agonist activity at 100 µM, although it displayed binding with a Ki value of 14.5 µM, suggesting antagonist activity. We have now identified novel modulators of A2AAR, A2BAR and A3AR subtypes that are clinically used for other therapeutic indications, and which are structurally distinct from previously reported tool compounds or drugs.

Tubeimoside-1 (TBMS-1), a natural triterpenoid saponin found in traditional Chinese herbal medicine Bolbostemmatis Rhizoma, is present in numerous Chinese medicine preparations. This review aims to comprehensively describe the pharmacology, pharmacokinetics, toxicity and targeting preparations of TBMS-1, as well the therapeutic potential for cancer treatement. Information concerning TBMS-1 was systematically collected from the authoritative internet database of PubMed, Web of Science, and China National Knowledge Infrastructure applying a combination of keywords involving “tumor,” “pharmacokinetics,” “toxicology,” and targeting preparations. New evidence shows that TBMS-1 possesses a remarkable inhibitory effect on the tumors of the respiratory system, digestive system, nervous system, genital system as well as other systems in vivo and in vitro. Pharmacokinetic studies reveal that TBMS-1 is extensively distributed in various tissues and prone to degradation by the gastrointestinal tract after oral administration, causing a decrease in bioavailability. Meanwhile, several lines of evidence have shown that TBMS-1 may cause adverse and toxic effects at high doses. The development of liver-targeting and lung-targeting preparations can reduce the toxic effect of TBMS-1 and increase its efficacy. In summary, TBMS-1 can effectively control tumor treatment. However, additional research is necessary to investigate in vivo antitumor effects and the pharmacokinetics of TBMS-1. In addition, to reduce the toxicity of TBMS-1, future research should aim to modify its structure, formulate targeting preparations or combinations with other drugs.

The bulk Cu billets with ultrafine-grained microstructure were successfully processed from full-annealed coarse grained oxygen-free high conductivity (OFHC) Cu by the cyclic extrusion and closed compression (CECC), subsequently annealed at different temperatures. The evolution of the microstructure and mechanical properties was systematically studied. The results show that the effective strain per CECC process is ε=2.77, with further annealing treatment, a high-efficiency grain refinement is realized. After two cycles of CECC process and annealing at 350 °C for 1 h, the grain size refined to ～3 μm, the tensile strength increased to 280 MPa with a high ductility of 54%. Furthermore, a homogeneous structure and mechanical properties in the bulk copper billets for post-forging could be obtained.

Wireless local area networks (WLANs) manage multiple access points (APs) and assign scarce radio frequency resources to APs for satisfying traffic demands of associated user devices. This paper considers the channel allocation problem in WLANs that minimizes the mutual interference among APs, and puts forth a learning-based solution that can be implemented in a decentralized manner. We formulate the channel allocation problem as an unsupervised learning problem, parameterize the control policy of radio channels with graph neural networks (GNNs), and train GNNs with the policy gradient method in a model-free manner. The proposed approach allows for a decentralized implementation due to the distributed nature of GNNs and is equivariant to network permutations. The former provides an efficient and scalable solution for large network scenarios, and the latter renders our algorithm independent of the AP reordering. Empirical results are presented to evaluate the proposed approach and corroborate theoretical findings.

Traditional approaches to the design of multi-agent navigation algorithms consider the environment as a fixed constraint, despite the obvious influence of spatial constraints on agents' performance. Yet hand-designing improved environment layouts and structures is inefficient and potentially expensive. The goal of this paper is to consider the environment as a decision variable in a system-level optimization problem, where both agent performance and environment cost can be accounted for. We begin by proposing a novel environment optimization problem. We show, through formal proofs, under which conditions the environment can change while guaranteeing completeness (i.e., all agents reach their navigation goals). Our solution leverages a model-free reinforcement learning approach. In order to accommodate a broad range of implementation scenarios, we include both online and offline optimization, and both discrete and continuous environment representations. Numerical results corroborate our theoretical findings and validate our approach.

Antibiotics, among the most used medications in children, affect gut microbiome communities and metabolic functions. These changes in microbiota structure can impact host immunity. We hypothesized that early-life microbiome alterations would lead to increased susceptibility to allergy and asthma. To test this, mouse pups between postnatal days 5-9 were orally exposed to water (control) or to therapeutic doses of azithromycin or amoxicillin. Later in life, these mice were sensitized and challenged with a model allergen, house dust mite (HDM), or saline. Mice with early-life azithromycin exposure that were challenged with HDM had increased IgE and IL-13 production by CD4

This paper investigates whether analyst site visits, where sell-side analysts visit corporate sites and interact with management, reduce earnings management by host firms. Taking advantage of the disclosure of analyst site visits by Chinese listed firms, we find that the intensity of analyst site visits is negatively associated with discretionary accruals, and this relation is robust to controlling for endogeneity. Furthermore, we find that site visits attended by star analysts and including factory tours are associated with lower levels of discretionary accruals than those without these features. We also report that the number and coverage of questions posed during site visits are negatively associated with discretionary accruals. Our results demonstrate that site visits by sell-side analysts perform a vital monitoring role and exert significant constraints on firms' opportunistic financial reporting.

Supplemental Material, sj-docx-1-ang-10.1177_00033197211021195 for Relationship Between High-Sensitivity C-Reactive Protein and Long-Term Outcomes in Elderly Patients With 3-Vessel Disease by Yue Liu, Ce Zhang, Lin Jiang, Lianjun Xu, Jian Tian, Xueyan Zhao, Xinxing Feng, Dong Wang, Yin Zhang, Kai Sun, Jingjing Xu, Ru Liu, Bo Xu, Wei Zhao, Rutai Hui, Runlin Gao, Zhan Gao, Lei Song and Jinqing Yuan in Angiology

Additional file 1. The primers and methods used in the research.

Additional file 1: Table S1. Summary of cause of mortality. Figure S1. Restricted cubic splines of FIB levels in relation to relative hazard ratio for all-cause death and cardiac death. Figure S2. Kaplan-Meier analysis for cardiac death according to different FIB levels and glycemic metabolism status. Figure S3. Relations of different glycemic metabolism status and cardiac death in univariate and multivariate survival analysis.

Additional file 2: Table S1 Detailed information of serum samples used in the study.

Additional file 1: Table S1. Baseline characteristics of the study population before and after inverse probability of treatment weighting.

Additional file 3: Table S3. Inverse probability of treatment weighting (IPTW) regression analysis based on propensity score.

Additional file 2: Table S2. Competing risks regression for cardiac death and other cardiovascular endpoints.

This paper reviews failure modes and mechanisms of 0.5 μm, 0.25 μm and 0.15 μm AlGaN/GaN HEMTs for microwave and millimeter-wave applications. Early devices adopting Ni/Pt/Au metallization were found to be affected by sidewall interdiffusion of Au and O, followed by electrochemical oxidation of AlGaN, a problem which was solved by adopting a new metallization and passivation scheme providing 0.25 μm devices capable of withstanding 24h at V DS = 60V, on-state, T ch = 375°C with no failure. 4000 h long-term thermal storage tests with no bias identified a non-monotonic behaviour of gate Schottky barrier height, causing a temporary increase of gate leakage current which presented no risk for device reliability. Beside contact-related degradation mechanisms, hot electron effects become increasingly more relevant during DC life tests (inducing a 10% increase of on-resistance), rf tests (creating or re-activating deep levels, which increase current-collapse and reduce rf output power and gain). RF tests are the harshest ones for hot-electron degradation, which represents the limiting factor for GaN HEMTs having L G ≤ 0.15 μm.

This study assessed the in vitro antibacterial activity of minocycline-aminoglycoside combination against Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae. Seventy non-duplicate clinical isolates of KPC-producing K. pneumoniae were collected from patients with bloodstream infections. The synergistic activity of minocycline-aminoglycoside combination was studied by the checkerboard method and time-kill assays in strains with different susceptibilities, and the mutant prevention concentration (MPC) and mutant selection window (MSW) of drugs alone and in combination were determined. The checkerboard method found this combination displayed synergistic and partial synergistic activity against aminoglycoside-susceptible isolates, but indifferent activity against aminoglycoside-resistant isolates. Time-kill assays further demonstrated strong synergistic and bactericidal effect of this combination existed against isolates which were susceptible to both drugs. But for resistant isolates, the time-kill assays showed no synergy. The MPCs of minocycline or aminoglycosides were 8- to 32-fold higher than the MICs, suggesting the MSWs of these drugs were quite wide. For the antibiotic combinations, the addition of 1×MIC concentration of amikacin or gentamicin could reduce the MPCs of minocycline by 4- to 16-fold. Generally, no mutants recovered in the plates containing 1×MIC concentration of minocycline and 2×MIC concentration of amikacin or gentamicin. In summary, these results suggest that minocycline-aminoglycoside combination can be an alternative for infections caused by KPC-producing K. pneumoniae because this combination displays strong synergistic and bactericidal activity in susceptible isolates, and can effectively prevent the emergence of resistant mutants. Further in vitro pharmacokinetic/pharmacodynamic studies and clinical trials should be performed to fully evaluate the efficacy of this drug combination.

In this hospital-based descriptive study, the genotype distribution of human papillomavirus (HPV) among HPV-infected women were investigated in 4,305 gynecological patients in Sichuan province. Females attending gynecology clinics between March 2014 and March 2015 were subjected to HPV screening after giving informed consent. Cervical scrapings were examined by cytopathology and colposcopy-directed biopsies. HPV genotyping was performed on a Luminex 200 system. Seventeen high-risk (HR) genotypes (HPV-16, -18, -31, -33, -35, -39, -45, -51, -52, -53, -56, -58, -59, -66, -68, -73, and -82) and seven low-risk (LR) genotypes (HPV-6, -11, -42, -43, -61, -81, and -83) were detected. Among all HPV-positive women, 34.1% (1,467/4,305) of the cases showed abnormal cytology and biopsy, including high-grade squamous lesions (HSIL), cervical intraepithelial neoplasias of grades 2 and 3 (CIN2/CIN3), and cervical cancer (CC). HPV-16, -52, and -58 were the predominant genotypes, followed by HPV-56, -18, -59, -39, -53, -33, and -81. A total of 3,785 (87.9%) HPV positive women were found to have HR HPV infection, while 859 (20.0%) were found to have LR HPV infection. Among all patients, 79% (3,401/4,305) were infected with a single strain of HPV, 85.5% (2,907/3,401) cases of which were of the HR HPV genotype. In cervical precancerous lesions (CPLs) and CC patients, HR HPV-16, -58, -52, -33, and -18 were the predominant genotypes. Interestingly, 33 CPL patients had a single LR HPV infection with HPV-61, -11, -81, -6, -43, or -42. Furthermore, one CC patient was infected only with LR HPV-11. According to the abundant genotype diversity of HPV in Sichuan, we suggest that a large-scale epidemiological investigation should be launched, not only to understand the distribution of HPV genotype, but also to provide information needed for HPV vaccination programs and to predict the effectiveness of current vaccines in Southwest China.

A variational wavefunction including the breather, dipole and scissor modes simultaneously is constructed to investigate the collective-excitation dynamics of spin-1 $$^{87}\mathrm{Rb}$$ condensates driven by a space- and time-dependent magnetic field. When the Dirac point never enters the condensate, it is shown that the dipole, breather and scissor modes will be all excited driven by the sinusoidal oscillation of the Dirac point, due to the coupling of different collective modes from the inhomogeneity of the magnetic field. A resonance-driving phenomenon is observed. If the Dirac point passes through the condensate, our numerical results agree with most experimental observations (Ray et al. in Nature 505:657, 2014) and find that the center of mass of the condensate does not follow the zero point of the magnetic field. Hopefully, our method can be extended to study the similar dynamics for the other spinor condensates.

The three participant self-rating scales of symptoms. This document provides the full details of three participant self-rating scales: criteria sheet for evaluating the severity of urinary system infection (CSESUSI); symptoms score sheet of TCM (SSST); OABSS. (DOCX 21 kb)

SPIRIT 2013 checklist. This document provides the recommended items to address in a clinical trial protocol and related document. (DOC 167 kb)

Since the requirements of digital nuclear power plant of China’s current construction of the signal transmission is high, and at the request of the high precision and complex working conditions, there is great significance to control the nuclear power plant “neural network” through the accurate and reliable signal in the digital platform integration analysis. In order to ensure the important signals can still transfer effectively in earthquake condition, this paper mainly combines engineering design, study on the standard requirements and principle for layout and mechanical calculation and seismic analysis of the instrumentation tubing in digital nuclear power plant. Establishment interface of instrumentation tubing and mechanical calculation according to the 3D model (three-dimensional model), the design method of seismic instrument pipeline of nuclear power plant is formed. It provides guidance and practical basis for the seismic design of instrumentation pipeline of the following intelligent digital nuclear power plant.

Clinical Trials.gov, NCT03658291. This document provides full registration information. (PDF 75 kb)

ObjectiveTo investigate the role of thyroid hormones and other factors in acute aortic dissection and an association with in-hospital adverse events.DesignA retrospective analysis.SettingA university-affiliated cardiac center.ParticipantsA total of 151 patients with aortic dissection admitted to the authors’ hospital between January 2011 and May 2015.InterventionNone.Measurements and ResultsThe total in-hospital mortality rate was 12.6%. Triiodothyronine (T3) level was lower in nonsurviving than surviving patients (0.8±0.3 v 1.0±0.4 nmol/L, p

We simulate the dynamics of spin-2 87Rb condensate in a time and space-dependent magnetic field with a time-dependent variational approach. The topological Hall effect is observed, which has been realized in the experiment of spin-1 23Na condensate [Phys. Rev. Lett. 111, 245301 (2013)]. A driving-induced resonance behavior is observed.

We simulate numerically the dynamics of $$^{23}$$ Na condensate in a time- and space-dependent magnetic field with a variational approach. It is shown to be an efficient method to describe the complex dynamics of the system, which may excite the breather mode, the scissor mode, and the dipole mode simultaneously. Our results agree with the experimental observations of Choi et al. (Phys Rev Lett 111:245301, 2013). We reproduce qualitatively the geometric Hall effect and resonance behavior. We also find that the condensate shows a scissor-mode-like motion, which may play the shearing force to deform the condensate and consequently leads to the dynamical nucleation of quantized vortices.

Diverse therapies for the management of anastomotic leakage after esophageal atresia repair have been reported with various outcomes. The surgical management of anastomotic leakage after esophageal atresia repair can be challenging. We present a child with long-gap esophageal atresia and anastomotic leakage repair with pericardium. This article aimed to illustrate that pericardium may be a substitute for esophageal leakage repair.

Aims Atrial fibrillation is the most common heart disease. Previous research has found that several members of the matrix metalloproteinase (MMP) family are involved. However, the role of the most recently discovered member of the MMP family, MMP-28, has not been fully investigated. The present study aimed to reveal the role of MMP-28 in atrial fibrillation. Main methods 254 patients with sinus rhythm, paroxysmal atrial fibrillation, or persistent atrial fibrillation were enrolled in this prospective observational study. Circulating MMP-28, echocardiography, and other clinical variables were measured at hospital admission. Patients were followed for up to 7 months, and the end-point was occurrence of heart failure. Key findings MMP-28 was significantly higher in patients with atrial fibrillation than with sinus rhythm, and MMP-28 level was correlated with left atrial diameter. Additionally, MMP-28 independently predicted follow-up heart failure. Other clinical risk factors were previous myocardial infarction, brain natriuretic peptide, persistent atrial fibrillation, and left atrial diameter. MMP-28 increased the performance of prognostic prediction of heart failure. Significance Circulating MMP-28 was elevated in atrial fibrillation. MMP-28 may be related to atrial fibrillation and heart failure.

Supporting information. (DOCX 1440Â kb)

In order to make a better convergence of old and new roadbed,according to treatment technology about highway reconstruction project of new and old roadbed lap,we introduced the four good construction technology detailedly used in the construction process. Four kinds of processing technology can significantly reduce differential settlement caused by road diseases,and strengthen the widening subgrade integrity.The results show that the appropriate cutting slope and excavation steps, a good degree of compaction, the rational use of geosynthetic materials, the use of the use of high quality packing can make the new and old roadbed integrity, achieve good effect of design and construction and reduced the incidence of disease.

The combined miniemulsion and solvent evaporation (MESE) method was employed to fabricate hydrophobic dye/polymer composite colorants in the present work. Using dynamic light scattering tests, the effect of the formulation variables on the size and size distribution of the prepared nanoparticles was examined. Transmission electron microscopy, UVvisible spectrophotometry, X-ray photoelectron spectroscopy, and elemental analysis results indicate that dye molecules or aggregates were successfully encapsulated in the poly (methyl methacrylate) matrix using the MESE method and the resulting composite colorant could be dispersed in water.

Mg-Y-Nd-Gd-Zn-Zr magnesium alloys with six different compositions are prepared through sand casting. A research shall be conducted on the casting structure and mechanical properties at room temperature of this magnesium alloys and the effect of main alloying rare earth elements of Y, Gd and Nd is researched through analysis on the test data of mechanical properties. It is seen from the research: In as-as-cast alloys, Y and Gd have a larger solid solubility, which are tend to uniform distribution in the alloy but there is much more Nd to precipitate. The second phase is mainly covered by Mg12Nd and a few of Mg24Y5and Mg5Gd which are in form of block, globularity and strip. After T6 treatment, a large number of intermetallic compounds of Mg24Y5with Y are precipitated from the alloy and the second phase has changed significantly in size and morphology which is uniformly and widely distributed in the grain and grain boundary with a good strengthening effect. When a few of Gd is added, the strength and plasticity of matrix alloy are improved. With the adding of Gd, the precipitated phase of microstructure is also increased which is tend to coarsening and segregation so as to have an effect on its mechanical properties.

In order to obtain the level of security of the pressure vessel with pit defects, a safety evaluation simulation system bases on the failure paths of pit defects was used to find the level of dynamic security. The parallel method or radial method can not be used to get the real level of dynamic security of pit defects, but the distance along the failure path to the safety critical line, and a new way was provided in detail.

In this paper, a new type of warming compound blocks with slag concrete was designed and prepared. The effect of specification, hole pattern and form of warming compound blocks on the thermal property of the blocks was researched. The results show that, with the addition of slag, EPS and aerated concrete, the thermal property will be improved greatly. The thermal resistance of warming compound blocks with three rows of EPS would reach 1.13 m2•K/W, and the thermal resistance of warming compound blocks with three rows of aerated concrete would reach 0.83 m2•K/W.

Background and Aim Helicobacter pylori can survive long incubation periods under anaerobic conditions, and should be possible to isolate under anaerobic conditions. Our aim was to isolate H. pylori in anaerobic conditions, from gastric biopsies of H. pylori infected patients. Methods We enrolled 27 patients with bleeding (erosive) gastritis (mean age 36.3 years, 55.6% male) from Hanoi, Vietnam. H. pylori status was confirmed by qPCR. Results H. pylori were recovered under anaerobic and micro-aerobic conditions from gastric biopsies in 16 patients. Anaerobic conditions yielded significantly higher H. pylori recovery rates than micro-aerobic conditions (81.3% vs. 31.3%, P = 0.01). H. pylori isolates were characterized by PCR for specific virulence markers and the genotypes were similar to those previously described in this region of the world. Conclusions H. pylori can be isolated under anaerobic conditions. These findings may provide new insight into the physiology of this human pathogen and help to identify the route of H. pylori transmission.