检索结果-南通市图书馆

An Outbreak of Serogroup Y Meningococcal Meningitis in a Private Secondary Vocational School-Guangzhou City,Guangdong Province,China,2023

引用

China CDC weekly 2024年第12期6卷 242-246,I0005页

作者： xiang Zeng Qing He Yilan Li Yong Zhou Xiaoping Shao Pei Hu Jian liang Yudan Song Chao Ma Lijie Zhang Limei sun Lei Luo Chinese Field Epidemiology Training Program Chinese Center for Disease Control and PreventionBeijingChina Zhuhai Center for Disease Control and Prevention Zhuhai CityGuangdong ProvinceChina Guangdong Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina Guangzhou Center for Disease Control and Prevention Guangzhou CityGuangdong ProvinceChina Institute of Public Health Guangzhou Medical University&Guangzhou Center for Disease Control and PreventionGuangzhou CityGuangdong ProvinceChina Department of the National Immunization Programme Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?The inclusion of meningococcal vaccines in the National Immunization Program(NIP)over several years has significantly reduced the incidence of meningococcal meningitis in China to historic lows.Worldwide,there has been a diversification of meningococcal serogroups,leading to a shift in dominant serogroups in China from serogroup A to serogroups C and B,accompanied by a rise in reports of serogroups Y and W.What is added by this report?An outbreak of serogroup Y Neisseria meningitidis(Nm)in a secondary vocational school involved a single confirmed severe case and 24 individuals with laboratory-confirmed Nm carriage.Epidemiological investigation revealed that the outbreak was localized to the classroom of the confirmed case.Prolonged close contact within a confined space was identified as a significant risk factor for Nm transmission.The genotype sequence identified was type 1655(ST-1655),which is categorized under clonal complex 23(CC-23)and bears resemblance to 8 previously confirmed cases of serogroup Y meningococcal meningitis within Guangdong Province.This suggests that serogroup Y infections continue to sporadically emerge and have become prevalent strains.What are the implications for public health practice?This outbreak underscores the critical need to enhance surveillance of meningococcal serogroups and population carrier,and advocate for vaccination with MenY-containing vaccines.

关键词： break Secondary Guangdong

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

NiO-Doped Fe_(2)O_(3)/MgO Properties for the Chemical Looping Oxidative Dehydrogenation of Ethane

引用

China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 27-33页

作者： liang Hao Chen Junjie sun Jie sun Hui Shenyang Ligong University Shenyang 110159China Fushun Ecology Environment Bureau Qingyuan County Branch Fushun 113399China

Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for ethylene preparation.Fe_(2)O_(3)/MgO oxygen carrier was prepared using the co-precipitation method.The influence of added NiO and its different loadings on Fe_(2)O_(3)/MgO were investigated.Then,a series of oxygen carriers were applied in the CL-ODH of the ethane cycle system.Brunauer-Emmett-Teller(BET),X-ray diffractometry(XRD),X-ray photoelection spectroscopy(XPS),and H2-temperature programmed reduction(TPR)were used to characterize the physicochemical properties of these oxygen carriers.It was confirmed that an interaction between NiO and Fe_(2)O_(3) occurred based on the XPS and H2-TPR results.Based on the CL-ODH activity performance tests conducted in a fixed-bed reactor,it was revealed that ethylene selectivity was significantly improved after NiO addition.Fe_(2)O_(3)-10%NiO/MgO showed the best activity performance with 93%ethane conversion and 50%ethylene selectivity at a reaction temperature of 650℃,atmospheric pressure,and space velocity of 7500 mL/(g·h).

关键词： chemical looping oxidative dehydrogenation oxygen carrier Fe_(2)O_(3)/MgO NiO

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Adversarial data splitting for domain generalization

引用

Science China(Information Sciences) 2024年第5期67卷 28-42页

作者： xiang GU Jian sun Zongben XU School of Mathematics and Statistics Xi'an Jiaotong University

Domain generalization aims to learn a model that is generalizable to an unseen target domain,which is a fundamental and challenging task in machine learning for out-of-distribution generalization. This paper proposes a novel domain generalization approach that enforces the learned model to be able to generalize well over the train/val subset splitting of the training dataset. This idea is modeled herein as an adversarial data splitting framework, formulated as a min-max optimization problem inspired by the metalearning approach. The min-max optimization problem is solved by iteratively splitting the training dataset into the training and val subsets to maximize the domain shift measured by the objective function and updating the model parameters to enable the model to generalize well from the training subset to the val subset by minimizing the objective function. This adversarial training approach does not assume the known domain labels of the training data; instead, it automatically investigates the “hard” splitting of the train/val subsets to learn the generalizable model. Extensive experimental results using three benchmark datasets demonstrate the superiority of this approach. In addition, we derive a generalization error bound for the theoretical understanding of our proposed approach.

关键词： domain generalization adversarial learning data splitting meta-learning out of distribution

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography

引用

International Journal of Ophthalmology(English edition) 2024年第1期17卷 42-52页

作者： Hai-Li Huang Guan-Hong Wang liang-liang Niu Xing-Huai sun Department of Ophthalmology&Visual Science Eye&ENT HospitalShanghai Medical CollegeFudan UniversityShanghai 200031China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China NHC Key Laboratory of Myopia Chinese Academy of Medical Sciencesand Shanghai Key Laboratory of Visual Impairment and Restoration(Fudan University)Shanghai 200031China

AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.

关键词： choroidal thickness choroidal vascularity index swept-source optical coherence tomography acute primary angle-closure chronic primary angle-closure glaucoma

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A projected Newton algorithm based on chemically allowed interval for chemical equilibrium computations

引用

Frontiers of Chemical Science and Engineering 2024年第3期18卷 25-37页

作者： Hongbin Lu Shaohui Tao Xiaoyan sun Li Xia Shuguang xiang Institute of Process Systems Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China

The chemical equilibrium equations utilized in reactive transport modeling are complex and nonlinear,and are typically solved using the Newton-Raphson method.Although this algorithm is known for its quadratic convergence near the solution,it is less effective far from the solution,especially for ill-conditioned problems.In such cases,the algorithm may fail to converge or require excessive iterations.To address these limitations,a projected Newton method is introduced to incorporate the concept of projection.This method constrains the Newton step by utilizing a chemically allowed interval that generates feasible descending iterations.Moreover,we utilize the positive continuous fraction method as a preconditioning technique,providing reliable initial values for solving the algorithms.The numerical results are compared with those derived using the regular Newton-Raphson method,the Newton-Raphson method based on chemically allowed interval updating rules,and the bounded variable least squares method in six different test cases.The numerical results highlight the robustness and efficacy of the proposed algorithm.

关键词： chemical equilibrium reactive transport modeling numerical methods projected Newton method

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rotor Angle Stability Prediction Using Temporal and Topological Embedding Deep Neural Network Based on Grid-informed Adjacency Matrix

引用

Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 695-706页

作者： Peiyuan sun Long Huo Xin Chen Siyuan liang the School of Electrical Engineering Xi'an Jiaotong University the School of Electrical Engineering and the Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University the Department of Computer Science and Engineering The Chinese University of Hong Kong

Rotor angle stability(RAS) prediction is critically essential for maintaining normal operation of the interconnected synchronous machines in power systems. The wide deployment of phasor measurement units(PMUs) promotes the development of data-driven methods for RAS prediction. This paper proposes a temporal and topological embedding deep neural network(TTEDNN) model to accurately and efficiently predict RAS by extracting the temporal and topological features from the PMU data. The grid-informed adjacency matrix incorporates the structural and electrical parameter information of the power grid. Both the small-signal RAS with disturbance under initial operating conditions and the transient RAS with short circuits on transmission lines are considered. Case studies of the IEEE 39-bus and IEEE 300-bus power systems are used to test the performance, scalability, and robustness against measurement uncertainties of the TTEDNN model. Results show that the TTEDNN model performs best among existing deep learning models. Furthermore, the superior transfer learning ability from small-signal RAS conditions to transient RAS conditions has been proved.

关键词： Power system stability Phasor measurement units Rotors Transient analysis Stability criteria Deep learning Circuit stability

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

An Adaptive Program Recommendation System for Multi-User Sharing Environment

引用

China Communications 2024年第6期21卷 112-128页

作者： sun Shiyun Hu Zhengying Wei Xin Zhou liang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

More and more accounts or devices are shared by multiple users in video applications,which makes it difficult to provide recommendation service.Existing recommendation schemes overlook multiuser sharing scenarios,and they cannot make effective use of the mixed information generated by multi-user when exploring users’potential interests.To solve these problems,this paper proposes an adaptive program recommendation system for multi-user sharing environment.Specifically,we first design an offline periodic identification module by building multi-user features and periodically predicting target user in future sessions,which can separate the profile of target user from mixed log records.Subsequently,an online recommendation module with adaptive timevarying exploration strategy is constructed by jointly using personal information and multi-user social information provided by identification module.On one hand,to learn the dynamic changes in user-interest,a time-varying linear upper confidence bound(LinUCB)based on personal information is designed.On the other hand,to reduce the risk of exploration,a timeinvariant LinUCB based on separated multi-user social information from one account/device is proposed to compute the quality scores of programs for each user,which is integrated into the time-varying LinUCB by cross-weighting strategy.Finally,experimental results validate the efficiency of the proposed scheme.

关键词： adaptive exploitation LinUCB multiuser recommendation system

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nanoimprint-induced strain engineering of two-dimensional materials

引用

Microsystems & Nanoengineering 2024年第2期10卷 323-332页

作者： Chuying sun Jianwen Zhong Zhuofei Gan Liyang Chen Chuwei liang Hongtao Feng Zhao sun Zijie Jiang Wen-Di Li The University of Hong Kong Hong KongChina

The high stretchability of two-dimensional(2D)materials has facilitated the possibility of using external strain to manipulate their properties.Hence,strain engineering has emerged as a promising technique for tailoring the performance of 2D materials by controlling the applied elastic strain field.Although various types of strain engineering methods have been proposed,deterministic and controllable generation of the strain in 2D materials remains a challenging task.Here,we report a nanoimprint-induced strain engineering(NISE)strategy for introducing controllable periodic strain profiles on 2D materials.A three-dimensional(3D)tunable strain is generated in a molybdenum disulfide(MoS_(2))sheet by pressing and conforming to the topography of an imprint mold.Different strain profiles generated in MoS_(2)are demonstrated and verified by Raman and photoluminescence(PL)spectroscopy.The strain modulation capability of NISE is investigated by changing the imprint pressure and the patterns of the imprint molds,which enables precise control of the strain magnitudes and distributions in MoS_(2).Furthermore,a finite element model is developed to simulate the NISE process and reveal the straining behavior of MoS_(2).This deterministic and effective strain engineering technique can be easily extended to other materials and is also compatible with common semiconductor fabrication processes;therefore,it provides prospects for advances in broad nanoelectronic and optoelectronic devices.

关键词： strain dimensional molybdenum

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Disturbances rejection optimization based on improved two-degree-of-freedom LADRC for permanent magnet synchronous motor systems

引用

Defence Technology（防务技术） 2024年第3期33卷 518-531页

作者： Chenggang Wang Jianhu Yan Wenlong Li liang Shan Le sun School of Automation Nanjing University of Science and TechnologyNanjing 210094China

Permanent magnet synchronous motor(PMSM)speed control systems with conventional linear active disturbance rejection control(CLADRC)strategy encounter issues regarding the coupling between dynamic response and disturbance suppression and have poor performance in suppressing complex nonlinear disturbances.In order to address these issues,this paper proposes an improved two-degree-of-freedom LADRC(TDOF-LADRC)strategy,which can enhance the disturbance rejection performance of the system while decoupling entirely the system's dynamic and anti-disturbance performance to boost the system robustness and simplify controller parameter tuning.PMSM models that consider total disturbances are developed to design the TDOF-LADRC speed controller accurately.Moreover,to evaluate the control performance of the TDOF-LADRC strategy,its stability is proven,and the influence of each controller parameter on the system control performance is analyzed.Based on it,a comparison is made between the disturbance observation ability and anti-disturbance performance of TDOF-LADRC and CLADRC to prove the superiority of TDOF-LADRC in rejecting disturbances.Finally,experiments are performed on a 750 W PMSM experimental platform,and the results demonstrate that the proposed TDOF-LADRC exhibits the properties of two degrees of freedom and improves the disturbance rejection performance of the PMSM system.

关键词： Permanent magnet synchronous motor(PMSM) Active disturbance rejection control(ADRC) Disturbance observer Two-degree-of-freedom control Anti-disturbance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Full sexual maturity-cycle exposure to environmentally relevant concentrations of 17β-estradiol decreases reproductive capacity of zebrafish

引用

Journal of Environmental Sciences 2024年第3期137卷 580-592页

作者： Yongkang Zhang Yuanjun Jiang Qian sun Meng Li Sheng Chen Jingyu liang Chunsheng Liu College of Fisheries Huazhong Agricultural UniversityWuhan 430070China School of Environmental Studies China University of GeosciencesWuhan 430074China

17β-Estradiol(E2)has been widely detected in natural water and treatment with E2 induces potential endocrine disrupting effects in fish.However,effects on fish fecundity and steroid system after treatment with environmentally relevant concentrations of E2 for the full sexual maturation cycle remain unclear.In this study,zebrafish were treatment with 0,10 or100 ng/L E2 from embryo to adult stage,and effects on gonadal development and differentiation,steroid hormone levels,transcription of genes associated with the hypothalamic-pituitary-gonadal-liver(HPG)axis in adults and fertilization rate of offspring were assessed.The results showed that treatment with E2 lead to increased number of feminization in zebrafish.In females,E2 decreased cumulative amount of spawning and inhibited the maturation of oocyte.In males,E2 inhibited the maturation and motility of sperm,as well as decreased the movement speed of sperm.These adverse effects on sperm might be responsible for the reduced fertilization observed in offspring.In addition,treatment with E2 changed the levels of steroid hormones in zebrafish gonad and altered the transcriptional levels of genes associated with HPG axis,which is responsible for the regulation of germ cells maturation and gonadal development in zebrafish.Overall,these results suggested that treatment with environmentally relevant concentrations of E2 for the full sexual maturity cycle resulted in adverse effects on reproduction in zebrafish.

关键词： Environmental estrogen Zebrafish Fecundity Gonadal development Endocrine disruption

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：