Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2022-09-06 Cooperative journals: 《中国全科医学》
Abstract： Background Gp is a mainstay of the basic medical and health services, existing in the study of general practitioner competency, most emphasis on external medical knowledge and skills of ascension, ignores the importance of gp implicit quality, at present our country still lacks its implicit competency assessment tools effectively, thus developing gp implicit competent power table is inevitable requirement to improve the basic medical services.ObjectiveA scientific and reasonable scale of general practitioners' implicit competence was developed, and the scale with good reliability and validity was applied to the evaluation of general practitioners' implicit competence, providing certain reference value for improving general practitioners' competence.Methods After the initial scale was formed on the basis of literature analysis and behavioral event interviews, 380 questionnaires were randomly distributed online to the target population from September to December 2021, and 335 questionnaires were effectively recovered. The rationality of the scale was verified by item purification, exploratory factor analysis, confirmatory factor analysis and scale reliability and validity test. The weighted average method was used to evaluate the implicit competency of general practitioners. Results Gp implicit qualified strength work motivation, self-efficacy, medical humanities and medical professional four primary entry and 14 secondary entry, and good reliability and validity of the scale, gp implicit competency comprehensive overall score is 4.15, is in good level, and different gender, age, title, and other variables in the comprehensive score of show the difference.Conclusion The research and development of GPS implicit competent power table can effectively evaluate the competence level, decision-making for basic-level medical organization, GPS personal development to provide certain reference value, can work from cognitive and self identity, theoretical knowledge and practical application, the business ability and work attitude, organizational support and social acceptance four aspects to improve GPS comprehensive ability in the future.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2019-03-07 Cooperative journals: 《干旱区地理》
Abstract：基于新型城镇化特征及内涵，选取人口、经济、社会、空间、居民生活质量、城乡统筹发展和创新发展7个因素26项指标构建浙江省县域新型城镇化水平评价体系，运用模糊综合评价法计算了该省70个县域行政单元2007—2016年新型城镇化水平。在此基础上，采用ArcGIS对计算结果进行可视化表达和分析，并采用系统聚类法进行了验证。结果表明：（1）浙江省县域新型城镇化水平在时间上总体呈缓慢上升趋势，在空间上总体呈现“倒三角”特征；（2）形成三个高水平区域中心和两个低水平区域中心，高水平区域中心对周边区域带动辐射效应明显；传统城镇化指标对新型城镇化水平贡献较大，但城乡统筹发展和创新发展的贡献逐年上升；（3）新型城镇化水平较高区域得益于其创新发展，其城乡统筹发展和社会城镇化相较其他区域表现突出。
Subjects: Astronomy >> Astrophysical processes submitted time 2018-12-18 Cooperative journals: 《天文研究与技术》
Abstract： 快速射电爆（Fast Radio Burst 简称 FRB）于 2007 年首次在脉冲星搜索数据中被发现，是一种在射电波段强烈爆发的天体物理现象，其特征为持续时间一般仅为若干毫秒，峰值流量密度可达到央斯基量级。类似于射电脉冲星的单个脉冲但具有超过同一视线方向上整个银河系星际介质的预期总色散量，可作为研究离子化星系间介质和自由电子空间分布的宇宙学尺度探针。对截止 2018 年 6 月 Parkes 望远镜、GBT 望远镜、Arecibo 电望远镜、UTMOST 望远镜和 ASKAP 望远镜已探测到的 52 例 FRB 事件进行了观测量统计分析。排除来自银河系星际介质贡献的色散量后，FRB 平均色散量约为 584.521pccm -3 ，这暗示FRB来自河外。通过最佳拟合估算红移幂律分布谱 dN/dFobs=4.14±1.30×𝐹 𝑝𝑐𝑡− 1.12055 sky -1 day -1 。FAST 望远镜使用 19 波束接收机探测灵敏度后，FAST 多科学目标同时扫描巡天（CRAFTS）中估计经过一年时间的科学运行，FAST 能发现大约 10 个 FRB，将有效的扩大样本，为 FRB 研究提供重要信息。
Subjects: Library Science，Information Science >> Information Science submitted time 2017-11-08 Cooperative journals: 《数据分析与知识发现》
Abstract：【目的】解决科技查新领域检索词选择时的主观性强、手工工作量大、不规范、费时费力的问题。【应用背景】为了实现检索词抽取过程的自动化、智能化、规范化, 本文提出利用科技查新过程检出的实时相关语料作为领域知识的来源, 并对语料组成类型与关键词抽取效果之间的关系进行讨论。【方法】通过关键词抽取、领域特征扩展相结合的递进式迭代抽取方式实现科技查新领域检索词的智能抽取。【结果】通过与实际查新案例所采用的检索词对比, 发现使用本方法两次迭代后抽取10 个检索词, 召回率达到80%。【结论】基于查新过程中检出文献构成的动态相关语料进行检索词的迭代抽取有助于快速、准确锁定绝大部分检索词, 提高检索的效率和效果。
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： 2.25Cr-1Mo-0.25V steel is the most popular material used for pressure-vessel applied at elevatedtemperature in hydrogen environment. For higher process efficiencies in future coal- conversion plants, chemical processing plants, and petrochemical-refining plants, much thicker cross-section component are necessary for constructing much larger pressure- vessel for these plants. Because of the thick cross- section, the cooling rate in the central region of the component is insufficient to obtain low bainite during quenching treatment, and a large amount of granular bainite appears in the central region. Previous studies have shown that good impact toughness can be achieved by appropriate tempering for 2.25Cr-1Mo-0.25V steel with low bainite microstructure. However, the impact toughness of 2.25Cr-1Mo-0.25V steel with granular bainite after tempering always cannot satisfy the demanding requirement due to the unclear understanding of the evolution of microstructure and mechanical properties during tempering. In this work, the influence of tempering on the microstructure and mechanical properties of 2.25Cr-1Mo-0.25V steel with granular bainite microstructure was investigated by OM, XRD, SEM, TEM and EPMA. The results show that the normalized 2.25Cr-1Mo-0.25V steel with granular bainite microstructure is composed of bainite ferrite and island of martensite and austenite (M-A island). Nanoindentation test indicates that MA island is much harder than that of metrix bainite ferrite, because of the high concentration of carbon in M-A is-lands. The synergistic effect of the decomposition of M-A islands and softening of bainite ferrite determined that Charpy absorbed energy at -18 ℃ increases first and then decreases with the increasement of tempering temperature. The degree of decomposition of M-A islands and the morphology, size and distribution of carbides in granular bainite, coupled with the softening effect of bainite ferrite recrystallization are the key factors determining low-temperature impact toughness of 2.25Cr-1Mo-0.25V steel.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-19 Cooperative journals: 《金属学报》
Abstract： After quenching and proper intercritical tempering, ZG06Cr13Ni4Mo martensitic stainless steel is composed of tempered martensite matrix and reversed austenite. The deformation induced martensitic transformation of reversed austenite occurring during the deformation results in the transformation induced plasticity (TRIP) effect, which is beneficial to the mechanical properties of this steel. However, studies on the TRIP effect of reversed austenite are limited to description of phenomenon and mechanism behind is not clear. In order to reveal the mechanical stability and transformation induced plasticity of the reversed austenite during tension test in tempered ZG06Cr13Ni4Mo steel, a custom-built mini tensile instrument has been designed and installed on Shanghai Synchrotron Radiation Facility to conduct the in situ synchrotron high energy X-ray diffraction (SHXRD) experiment during the uniaxial tension. Three samples, which were tempered at 620 ℃ with different holding times and cooling rates in order to obtain different volume fraction of reversed austenite, were used to investigate the relationship between the deformation induced martensitic transformation and work hardening behavior. The integral intensityand the full width at half maximum of diffraction peaks of the reversed austenite and tempered martensitic matrix under different engineering stress were recorded. The gradual decrease in the integral diffraction intensity of reversed austenite with increase in tensile stress indicates that the reversed austenite has been induced to transform into martensite during the tension deformation. Furthermore, the volume fraction of reversed austenite during tension was quantitatively calculated by fitting the whole diffraction spectra of reversed austenite and tempered martensitic matrix with the Rietveld refinement method. The evolution of the reversed austenite fraction indicates that the deformation induced martensitic transformation initiates at the macro-elastic stage and through the whole deformation, which is different to the retained austenite in TRIP steel. Meanwhile, the work hardening exponents of three samples with different volume fraction of reversed austenite have been compared. It is found that the deformation induced martensitic transformation of reversed austenite increases the dislocation density of martensitic matrix and results in the increase in the work-hardening exponent during the plastic deformation, which enhances the ductility of ZG06Cr13Ni4Mo martensitic stainless steel.
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：脱氧雪腐镰刀菌烯醇(DON)对以谷物为基础的食物和饲料的污染是一个全球性问题，严重危害了人和动物的健康。DON在人和动物体内的代谢特征是开展DON暴露评估、毒性作用机制和干预技术等研究的基础。近年来有关DON的吸收、分布、代谢和排泄等毒物动力学的研究引起了国内外广泛关注。本文将DON代谢特征的最新进展进行了全面的综述。
Subjects: Materials Science >> Materials Science (General) submitted time 2017-04-10 Cooperative journals: 《材料研究学报》
Abstract：以预浸炭布和铜网为原料用模压压制法制备炭纤维体积分数分别为35%、40%和45%左右的三种C/C-Cu复合材料,用Instron3369力学试验机测试了压缩性能。结果表明：炭纤维的体积分数是影响材料压缩性能的重要因素。在垂直方向上,材料的压缩性能随着炭纤维体积分数的增加而提高。炭纤维体积分数为40%的试样其压缩性能比35%的试样提高了20%,炭纤维体积分数为45%的试样比40%的试样提高了13%,提高的幅度呈先大后小的趋势。而在平行方向上,炭纤维的体积分数对压缩性能的影响没有垂直方向的显著,与试样的致密度有一定的关系。在三种试样中,炭纤维体积分数为45%的试样无论在垂直方向还是平行方向上的压缩强度都最大,分别为190.13 MPa和83.39 MPa。在平行方向和垂直方向上压缩强度的差异表明,C/C-Cu复合材料的压缩性能具有明显的各向异性。关于材料压缩的破坏方式,在垂直压缩受力方向近似沿45°对角线方向时,破坏方式为纤维层、铜网与基体炭的分离以及基体炭的压溃破坏。在平行方向压缩时炭纤维发生褶皱,并在褶皱区域产生拉压应力,使纤维发生折曲或者断裂,最终使炭纤维和基体炭以及基体炭和铜网的界面分层劈裂。
Subjects: Chemistry >> Nuclear Chemistry submitted time 2024-06-12
Abstract： Background: The Ir-192 brachytherapy source is a high dose rate gamma radiation source characterized by a high central dose rate and a rapid dose fall-off at the periphery. In clinical treatments, this dose distribution allows the Ir-192 source to effectively protect the normal tissues and organs surrounding the tumor. Objective To establish a detailed structural model of a domestically produced high-dose-rate Ir-192 brachytherapy source using Monte Carlo simulation software, based on the dosimetric parameters recommended by the American Association of Physicists in Medicine (AAPM) in TG43-U1, and to perform simulation calculations. Methods Using the Monte Carlo software, a detailed structural model of the domestically produced high-dose-rate Ir-192 brachytherapy source was established. The simulated dosimetric parameters included the dose rate constant Λ, air kerma rate per unit activity, radial dose function , and anisotropy function . Results The simulated dose rate constant was 1.105 cGy·h-1·U-1, with a difference of less than 1.2% from the literature values. Air kerma rate per unit activity was 9.788×10-8 UBq-1, with a difference of 0.23% from the literature values. The radial dose function was obtained for distances from 0.5 to 20 cm from the source axis, and an empirical formula was fitted. Conclusions The domestically produced Ir-192 source model established using the Monte Carlo software shows good consistency with the literature-reported dosimetric parameters, indicating that this model can be used for clinical practice applications of domestically produced Ir-192 sources and has certain guiding significance.
Subjects: Chemistry >> Nuclear Chemistry submitted time 2024-06-07
Abstract： Background: The Ir-192 brachytherapy source is a high dose rate gamma radiation source characterized by a high central dose rate and a rapid dose fall-off at the periphery. In clinical treatments, this dose distribution allows the Ir-192 source to effectively protect the normal tissues and organs surrounding the tumor. Objective To establish a detailed structural model of a domestically produced high-dose-rate Ir-192 brachytherapy source using Monte Carlo simulation software, based on the dosimetric parameters recommended by the American Association of Physicists in Medicine (AAPM) in TG43-U1, and to perform simulation calculations. Methods Using the Monte Carlo software, a detailed structural model of the domestically produced high-dose-rate Ir-192 brachytherapy source was established. The simulated dosimetric parameters included the dose rate constant Λ, air kerma rate per unit activity, radial dose function , and anisotropy function . Results The simulated dose rate constant was 1.105 cGy·h-1·U-1, with a difference of less than 1.2% from the literature values. Air kerma rate per unit activity was 9.788×10-8 UBq-1, with a difference of 0.23% from the literature values. The radial dose function was obtained for distances from 0.5 to 20 cm from the source axis, and an empirical formula was fitted. Conclusions The domestically produced Ir-192 source model established using the Monte Carlo software shows good consistency with the literature-reported dosimetric parameters, indicating that this model can be used for clinical practice applications of domestically produced Ir-192 sources and has certain guiding significance.
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-07-31 Cooperative journals: 《中国全科医学》
LI, Jingjing
YUAN, Ding
WANG, Xiuling
KANG, Hongfei
LAI, Chengcheng
WANG, Peisong
LU, Guangping
GAO, Yanxia
Abstract： Background The emergence of virtual reality（VR）technology is the breakthrough of medical education reform. It is the focus of clinical educators to apply VR technology to medical education and discuss the application effect. The application of VR in the standardized training of residents（referred to as residential training）is not rare，but the literature on the application of VR in the residential training of general practice has not been reported. Objective To explore the effectiveness of VR technology in the residential training of general practice，and provide a reference for the promotion and application of VR technology in the residential training of general practice. Methods From May 16，2022 to August 16，2022，a total of 58 general practitioners in the grade of 2020 in the department of general practice in the First Affiliated Hospital of Zhengzhou University，Henan Province were selected as the research objects and divided into the experimental group（n=29）and control group（n=29）by using random number generator. The experimental group adopted the teaching method of combining traditional theoretical training and VR skills training，and the control group adopted the method of combining traditional theoretical training and traditional skills training. The training content included the first aid of cardiopulmonary resuscitation and electric defibrillation，the treatment process of organophosphorus poisoning，and treatment process of independent sudden dyspnea in the hospital. Questionnaires were distributed to investigate the basic information of the subjects and their understanding of VR before the training，theoretical and skill assessments were carried out respectively after training，and the two groups of students were compared in theoretical assessment results，skill assessment results，self-assessment results of the key points of training skills and satisfaction with teaching methods. Results There was no difference in gender，age and years of graduation between the experimental group and control group（P>0.05）. After training，the theoretical and skill assessment scores of the experimental group were higher than those of the control group，and the difference was statistically significant（P<0.05）. With an assessment score ≥ 80 as excellence in assessment，the excellent rate of theoretical assessment in the experimental group was higher than the control group（P<0.05）. The self-assessed rate of mastery of the key points of the first aid skills for electric defibrillation and organophosphorus poisoning in the experimental group was higher than the control group（P<0.05）. The satisfaction scores of study interest，self-study ability，clinical thinking and judgment ability，clinical comprehensive ability，simulation of clinical environment，improvement of teaching effect，preparation for clinical practice and whether teaching is helpful to them were all higher than those of the control group（P<0.05）. Conclusion Compared with the traditional teaching mode，the application of traditional theoretical training combined with VR skills training teaching method is conducive to stimulating the subjective motivation of general practice residents，and also effectively improves their mastery of professional knowledge，which has popularization value in the teaching of residential training of general practice.
Subjects: Astronomy >> Astrophysical processes submitted time 2020-06-09 Cooperative journals: 《天文研究与技术》
Abstract：500米口径球面射电望远镜FAST已投入科学运行，漂移扫描巡天采集数据量已超过1PB，预计每年新增至少5PB。现有数据处理软件如PRESTO、SIGPROC等已无法满足PB量级数据的快速处理要求。提出了一种基于PRESTO的分布式并行计算方法，整合利用数据库技术和异地异构计算资源，构建了一套命名Craber的计算加速系统。整体系统由FAST早期科学数据中心与国家天文台团队共同设计和实现。启用Craber子网计算集群D中55个计算节点，应用Parkes多波束巡天数据集和FAST漂移扫描数据验证了系统流程和搜索数据库。单个100MB Parkes巡天数据文件平均耗时36秒，单个128MB FAST巡天数据文件平均耗时22秒。该系统目前已实际参与FAST数据处理并产生数十颗脉冲星发现，有效帮助FAST加速数据处理和扩大新样本数量。
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Other Disciplines of Agriculture, Forestry,Livestock & Aquatic Products Science submitted time 2023-02-17 Cooperative journals: 《智慧农业（中英文）》
Abstract： As one of the important way for constructing smart agriculture, unmanned farms are the most attractive in nowadays, and have been explored in many countries. Generally, data, knowledge and intelligent equipment are the core elements of unmanned farms. It deeply integrates modern information technologies such as the Internet of Things, big data, cloud computing, edge computing, and artificial intelligence with agriculture to realize agricultural production information perception, quantitative decision-making, intelligent control, precise input and personalized services. In the paper, the overall technical architecture of unmanned farms is introduced, and five kinds of key technologies of unmanned farms are proposed, which include information perception and intelligent decision-making technology, precision control technology and key equipment for agriculture, automatic driving technology in agriculture, unmanned operation agricultural equipment, management and remote controlling system for unmanned farms. Furthermore, the latest research progress of the above technologies both worldwide are analyzed. Based on which, critical scientific and technological issues to be solved for developing unmanned farms in China are proposed, include unstructured environment perception of farmland, automatic drive for agriculture machinery in complex and changeable farmland environment, autonomous task assignment and path planning of unmanned agricultural machinery, autonomous cooperative operation control of unmanned agricultural machinery group. Those technologies are challenging and absolutely, and would be the most competitive commanding height in the future. The maize unmanned farm constructed in the city of Gongzhuling, Jilin province, China, was also introduced in detail. The unmanned farms is mainly composed of information perception system, unmanned agricultural equipment, management and controlling system. The perception system obtains and provides the farmland information, maize growth, pest and disease information of the farm. The unmanned agricultural machineries could complete the whole process of the maize mechanization under unattended conditions. The management and controlling system includes the basic GIS, remote controlling subsystem, precision operation management subsystem and working display system for unmanned agricultural machineries. The application of the maize unmanned farm has improved maize production efficiency (the harvesting efficiency has been increased by 3－4 times) and reduced labors. Finally, the paper summarizes the important role of the unmanned farm technology were summarized in solving the problems such as reduction of labors, analyzes the opportunities and challenges of developing unmanned farms in China, and put forward the strategic goals and ideas of developing unmanned farm in China.
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