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Review on the Development of Cosmetic Industry from the Perspective of Group Standards
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作者 Xue Wei You Weishan +1 位作者 Wu Jianghong Su Lihong 《China Detergent & Cosmetics》 CAS 2024年第1期10-19,共10页
From the perspective of group standards, the dynamics of the cosmetic industry in the past few years were briefly reviewed and analyzed, including the number of group standards published, types of group standards, gro... From the perspective of group standards, the dynamics of the cosmetic industry in the past few years were briefly reviewed and analyzed, including the number of group standards published, types of group standards, groups, and geographical distribution of the groups. The large number of participating groups and the wide range of geographical distribution indicated that group standards could play a positive role in the sustained and positive development of cosmetic industry. The future development of cosmetic industry was also prospected。 展开更多
关键词 group standard COSMETIC INDUSTRY
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Analysis of Standards Establishment for the Testing of Electrical Appliances
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作者 Xiaobin Xie 《Journal of Electronic Research and Application》 2024年第2期12-17,共6页
As science and technology continue to develop,power equipment has become an indispensable part of industrial production and daily life.Whether it is the precise automation machinery utilized on production lines or the... As science and technology continue to develop,power equipment has become an indispensable part of industrial production and daily life.Whether it is the precise automation machinery utilized on production lines or the convenient electrical appliances found in households,their functionality relies heavily on electrical technology.Nonetheless,without stringent safety and performance assurances,these devices could potentially endanger lives and property.Thus,this paper explores the development strategy for establishing a standardized system within the electrical testing service industry,aiming to ensure safety and reliability. 展开更多
关键词 Electrical testing The service industry Standard system construction
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Host cell protein quantification workflow using optimized standards combined with data-independent acquisition mass spectrometry
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作者 Steve Hessmann Cyrille Chery +2 位作者 Anne-Sophie Sikora Annick Gervais Christine Carapito 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第5期494-502,共9页
Monitoring of host cell proteins(HCPs)during the manufacturing of monoclonal antibodies(mAb)has become a critical requirement to provide effective and safe drug products.Enzyme-linked immunosorbent assays are still th... Monitoring of host cell proteins(HCPs)during the manufacturing of monoclonal antibodies(mAb)has become a critical requirement to provide effective and safe drug products.Enzyme-linked immunosorbent assays are still the gold standard methods for the quantification of protein impurities.However,this technique has several limitations and does,among others,not enable the precise identification of proteins.In this context,mass spectrometry(MS)became an alternative and orthogonal method that delivers qualitative and quantitative information on all identified HCPs.However,in order to be routinely implemented in biopharmaceutical companies,liquid chromatography-MS based methods still need to be standardized to provide highest sensitivity and robust and accurate quantification.Here,we present a promising MS-based analytical workflow coupling the use of an innovative quantification standard,the HCP Profiler solution,with a spectral library-based data-independent acquisition(DIA)method and strict data validation criteria.The performances of the HCP Profiler solution were compared to more conventional standard protein spikes and the DIA approach was benchmarked against a classical datadependent acquisition on a series of samples produced at various stages of the manufacturing process.While we also explored spectral library-free DIA interpretation,the spectral library-based approach still showed highest accuracy and reproducibility(coefficients of variation<10%)with a sensitivity down to the sub-ng/mg mAb level.Thus,this workflow is today mature to be used as a robust and straightforward method to support mAb manufacturing process developments and drug products quality control. 展开更多
关键词 Host cell proteins Absolute quantification standards Data-independent acquisition
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An Empirical Study of the Effect of Inquiry Teaching on the Development of High School Students'Critical Thinking Under the New Curriculum Standards
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作者 Chen Yilong Peng Jia 《Contemporary Social Sciences》 2023年第2期130-145,共16页
The Ministry of Education of the People’s Republic of China has issued three guideline documents to encourage inquiry teaching to help students develop their ability to question,which is a defining feature of critica... The Ministry of Education of the People’s Republic of China has issued three guideline documents to encourage inquiry teaching to help students develop their ability to question,which is a defining feature of critical thinking.Two of the documents have clearly stated that English subject teaching should focus on building students’thinking capacity.Critical thinking is an essential feature of building thinking capacity and a key element of the core competencies the English subject seeks to cultivate.This research measures the performance of students of two high school classes in the exams conducted at the beginning,in the middle,and at the end of the experiment period during which inquiry teaching was applied to enhance students’critical thinking ability.The experiment results show that inquiry teaching can improve students’academic performance in English study and help them better develop their language skills.The implementation of the inquiry design in teaching listening,reading,and writing conforms to the law that governs the development of critical thinking,and the adoption of inquiry teaching can promote the development of critical thinking. 展开更多
关键词 new curriculum standards inquiry method high school English learning critical thinking
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Research Status of Water Quality Criteria and Standards and Analysis on the Transformation Methods
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作者 Cheng LI Yihong WU +1 位作者 Yang ZHAO Ruyu YUAN 《Meteorological and Environmental Research》 CAS 2023年第3期69-72,共4页
Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue ... Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue of economic development and ecological protection in a coordinated way.However,all kinds of environmental benchmark values in China are lacking and need to be constantly supplemented and improved.Therefore,exploring and putting forward a simple and efficient method for the transformation of environmental criteria into environmental standards is an important basis for the rapid establishment of relevant environmental criteria system and the effective promotion of the development of environmental standards system towards a scientific and reasonable direction.In this paper,the water environment is taken as the research object.By analyzing the research progress of environmental criteria and standards at home and abroad,and the foreign method of transforming environmental criteria into environmental standards,combined with the problems faced in the process of transforming environmental criteria into environmental standards in China,an effective method to transform China's environmental criteria into environmental standards is analyzed.After analysis and comparison,it is found that the pollution reduction accounting method could achieve their simple and efficient conversion.Under the premise of obtaining environmental criteria for certain pollutants,environmental criteria for certain pollutants could be obtained by distributing pollutants reduction costs,and accounting economic benefits after reaching standard,thus obtaining the environmental standard of this type of pollutant,which provides reference to determine the environmental standard limits of such pollutants. 展开更多
关键词 Water quality criteria Water quality standards Research status Transformation mechanism
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Challenges of the Performance Standards of the International Finance Corporation in Financing the African Integrated High-Speed Railway Network and the Way Forward: The Case of Standard Gauge Railway in Tanzania
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作者 Emmanuele Elifadhili Mchome Uwezo Wilbard Nzoya 《Journal of Transportation Technologies》 2023年第4期772-788,共17页
Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the Inte... Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the International Financial Institutions (IFIs). However, conditions provided by the IFIs through the Performance Standards (PS) of the International Financial Corporation (IFC) increase cost of the projects and thus, it becomes a burden to most of the African countries. This study aimed to explore the causes of IFC-PS through the SGR Projects that escalate costs and how to address them. The Tanzania SGR Lot 1 Project that covered 205 km from Dar es Salaam to Morogoro was selected as a case study. The methods used for data collection involved literature review, focus group discussions and interviews. The results and findings show a gap between the IFC-PS and the National Laws and Regulations that escalates costs of the projects if funds from the IFIs were to be secured. To bridge the gap, it is recommended that the African countries should engage into negotiations with the IFIs to agree to waive IFC-PS conditions that escalate costs provided they are adequately covered in the national laws and regulations;engagement of locally established national and regional financial institutions;and the responsible government institutions in the African countries should sit together for assessment and review of the IFC-PS against the national laws and regulations. 展开更多
关键词 African Integrated High-Speed Railway Network International Financial Institutions Standard Gauge Railway Performance standards
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Quality Standards of Carpesium lipskyi
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作者 Weiyu WANG Ruyin DONG +1 位作者 Xuemei LU Luyang LU 《Medicinal Plant》 CAS 2023年第3期33-37,共5页
[Objectives]The paper was to establish the quality standard of Carpesium lipskyi,and to provide a scientific reference for its quality control and rational development and utilization.[Methods]Morphological identifica... [Objectives]The paper was to establish the quality standard of Carpesium lipskyi,and to provide a scientific reference for its quality control and rational development and utilization.[Methods]Morphological identification,microscopic identification and thin layer chromatography(TLC)identification of the herbal samples were performed.The contents of moisture,total ash,acid-insoluble ash and alcohol-soluble extract of the herbal samples were determined,and their total flavonoid content was determined by UV-spectrophotometry.[Results]The average contents of moisture,total ash,acid-insoluble ash and alcohol-soluble extracts of 10 batches of C.lipskyi were 10.38%-12.27%,8.03%-14.72%,1.01%-3.06%and 20.84%-26.82%,respectively.The total flavonoids content ranged from 4.60%to 5.63%.[Conclusions]The established standard can provide a reference for the quality control of C.lipskyi.The tentative regulations stipulate that the moisture content of C.lipskyi shall not exceed 13.0%;the total ash content shall not exceed 15.0%;the acid-insoluble ash content shall not exceed 4.0%;the alcohol-soluble extract shall not be less than 16.0%;and the total flavonoids shall not be less than 3.0%. 展开更多
关键词 Carpesium lipskyi Winkl Quality standard Total flavonoids Content determination
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Application and Development Trends of Spectral Analysis in Draft of Non-Ferrous Metal Standards in China
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作者 Lijun Kuai Huachang Li +1 位作者 Jiemin Liu Shufang Tang 《American Journal of Analytical Chemistry》 2023年第6期239-273,共35页
Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of va... Spectral analysis was a method of identifying substances, determining their chemical composition and calculating their content based on their spectral characteristics. This paper mainly discussed the application of various spectroscopic techniques, mainly including atomic absorption spectrometry (AAS) inductively coupled plasma emission spectrometry (ICP-AES) X-ray fluorescence spectroscopy (XRF) atomic fluorescence spectroscopy (AFS) direct reading spectroscopy (OES) glow discharge emission spectroscopy (GD-OSE) laser-induced breakdown spectroscopy (LIBS), in the formulation of non-ferrous metal standards in China. The AAS method was the most widely used single-element microanalysis method among the non-ferrous metal standards. The ICP-AES method was good at significant advantages in the simultaneous detection of multiple elements. The XRF method was increasingly used in the determination of primary and secondary trace elements due to its simple sample preparation and high efficiency. The AFS was mostly detected by single-element trace analysis. OES GD-OES and LIBS were playing an increasingly important role in the new demand area for non-ferrous metals. This paper discussed matrix elimination, sample digestion, sample preparation, instrument categories and other aspects of some standards, and summarized the advantages of spectral analysis and traditional chemical analysis methods. The new methods of future spectroscopic technology had been illustrated in the process of developing non-ferrous metal standards. 展开更多
关键词 Atomic Absorption Spectroscopy Inductively Coupled Plasma Emission Spectroscopy X-Ray Fluorescence Spectroscopy Atomic Fluorescence Spectroscopy Direct Reading Spectroscopy Glow Discharge Emission Spectroscopy Laser-Induced Breakdown Spectroscopy Non-Ferrous Metals Standard Methods Were Formulated
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Inspiration of Foreign Innovative Drug Pricing Methods and Medical Insurance Payment Standards to China
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作者 Rao Xiuli Sun Lihua 《Asian Journal of Social Pharmacy》 2023年第4期365-373,共9页
Objective To study the innovative drug pricing methods and medical insurance payment standards in foreign countries and to provide reference for China’s government.Methods The official websites were searched for info... Objective To study the innovative drug pricing methods and medical insurance payment standards in foreign countries and to provide reference for China’s government.Methods The official websites were searched for information and related literature,and literature review was used.Results and Conclusion In foreign countries,the clinical value of innovative drugs and their impact on medical insurance funds were comprehensively evaluated based on factors such as quality-adjusted life years,clinical benefit,and improvement of clinical benefit.Then,the evaluation results were taken as an important basis for whether innovative drugs were admitted to the medical insurance catalog and establishing medical insurance payment standards.By using international experience for reference,innovative drug pricing methods and medical insurance payment standards for China’s national conditions can be improved by establishing a basic database of clinical value and drug economic evaluation of innovative drugs,as well as innovative drug payment models based on decision thresholds. 展开更多
关键词 innovative drug pricing method payment standard medical insurance international experience
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The Differences between Chinese Accounting Standards for Business Enterprises and International Financial Reporting Standards as well as the Convergence Strategy Method 被引量:1
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作者 Chuanqi Zhang Xiang Li Gan Luo 《Proceedings of Business and Economic Studies》 2019年第5期11-14,共4页
The continuous development and progress of international economic integration has resulted in the increasing of economic and trade exchanges between various countries.In order to implement a more systematic corporate ... The continuous development and progress of international economic integration has resulted in the increasing of economic and trade exchanges between various countries.In order to implement a more systematic corporate financial supervision mechanism effectively and adapt to the needs of economic development,it is necessary to clarify corporate accounting standards and international financial reporting standards.The relationship between them are crucial to improve the transparency of financial statements and optimize management levels.This paper analyzes the differences between Chinese business accounting standards and international financial reporting standards as well as discusses the convergence process and convergence strategy methods for reference. 展开更多
关键词 CHINESE Business Accounting standards International Financial REPORTING standards(IFRS) Differences CONVERGENCE
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First Forum on China Casting Quality Standards & Overview of Revision History of China's National/Industrial Standards for Foundry Operations
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《China Foundry》 SCIE CAS 2009年第3期276-279,共4页
  Both national and local governments have been paying great attention to the work of industrial standardization with the enormous increase in international trade after China joined WTO. According to the standards r...   Both national and local governments have been paying great attention to the work of industrial standardization with the enormous increase in international trade after China joined WTO. According to the standards revising plan of Standardization Administration Committee of China (SAC),TC54 has already revised a series of national standards and industrial standards for foundry operations,and proposed some new ones. As a result,some old fashioned standards containing low-level techniques have been gradually discontinued or replaced with new versions.…… 展开更多
关键词 In First Forum on China Casting Quality standards Overview of Revision History of China’s National/Industrial standards for Foundry Operations GB
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A review of lithium-ion battery safety concerns:The issues,strategies,and testing standards 被引量:29
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作者 Yuqing Chen Yuqiong Kang +8 位作者 Yun Zhao Li Wang Jilei Liu Yanxi Li Zheng Liang Xiangming He Xing Li Naser Tavajohi Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期83-99,I0003,共18页
Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fi... Efficient and reliable energy storage systems are crucial for our modern society.Lithium-ion batteries(LIBs)with excellent performance are widely used in portable electronics and electric vehicles(EVs),but frequent fires and explosions limit their further and more widespread applications.This review summarizes aspects of LIB safety and discusses the related issues,strategies,and testing standards.Specifically,it begins with a brief introduction to LIB working principles and cell structures,and then provides an overview of the notorious thermal runaway,with an emphasis on the effects of mechanical,electrical,and thermal abuse.The following sections examine strategies for improving cell safety,including approaches through cell chemistry,cooling,and balancing,afterwards describing current safety standards and corresponding tests.The review concludes with insights into potential future developments and the prospects for safer LIBs. 展开更多
关键词 Lithium-ion batteries standards Safety Thermal abuse Mechanical abuse Electrical abuse
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Overview on current criteria for heavy metals and its hint for the revision of soil environmental quality standards in China 被引量:14
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作者 CHEN Shi-bao WANG Meng +2 位作者 LI Shan-shan ZHAO Zhong-qiu E Wen-di 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第4期765-774,共10页
Following rapid social and economic development over the past several decades, soil pollution by heavy metals(HMs) has been both serious and widespread in China. The Soil Environmental Quality Standards(SEQSs) in Chin... Following rapid social and economic development over the past several decades, soil pollution by heavy metals(HMs) has been both serious and widespread in China. The Soil Environmental Quality Standards(SEQSs) in China(GB 15618-1995) have been introduced to encourage and enforce sustainable soil HM management. However, in recent years, HM contents in soils have frequently been found to exceed their associated standard values, while the crops growing on them might still meet regulatory standards, and vice versa. There is thus growing awareness that GB 15618-1995 does not effectively regulate current soil HM pollution, as it has encountered bottlenecks, and disappointing outcomes caused by poor execution along with deficiencies and gaps in the policies. However, due to the deficiency of scientific research about relationships between soil HM concentrations and their ecological or human health effects, the development of SEQSs in China is still greatly restricted. This paper discusses international SEQSs of HMs as well their development in China over time, then examines current Chinese SEQSs to demonstrate their potential regulatory deficiencies by referring to international SEQSs. The corresponding legislative policies are described, and scientific information or responses are outlined for maintaining soil environmental quality. China's experience has shown that policy and science can be linked to work in tandem to better understand and manage soil quality issues. 展开更多
关键词 SOIL HEAVY metals REGULATORY standards SOIL science policy
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Stricter national standards are required for credentialing of endoscopic-retrograde-cholangiopan-creatography in the United States 被引量:7
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作者 Mitchell S Cappell David M Friedel 《World Journal of Gastroenterology》 SCIE CAS 2019年第27期3468-3483,共16页
Endoscopic-retrograde-cholangiopancreatography(ERCP) is now a vital modality with primarily therapeutic and occasionally solely diagnostic utility for numerous biliary/pancreatic disorders. It has a significantly stee... Endoscopic-retrograde-cholangiopancreatography(ERCP) is now a vital modality with primarily therapeutic and occasionally solely diagnostic utility for numerous biliary/pancreatic disorders. It has a significantly steeper learning curve than that for other standard gastrointestinal(GI) endoscopies, such as esophagogastroduodenoscopy or colonoscopy, due to greater technical difficulty and higher risk of complications. Yet, GI fellows have limited exposure to ERCP during standard-three-year-GI-fellowships because ERCP is much less frequently performed than esophagogastroduodenoscopy/colonoscopy. This led to adding an optional year of training in therapeutic endoscopy. Yet many graduates from standard three-year-fellowships without advanced training intensely pursue independent/unsupervised ERCP privileges despite inadequate numbers of performed ERCPs and unacceptably low rates of successful selective cannulation of desired(biliary or pancreatic) duct. Hospital credentialing committees have traditionally performed ERCP credentialing, but this practice has led to widespread flouting of recommended guidelines(e.g., planned privileging of applicant with 20% successful cannulation rate, or after performing only 7 ERCPs);and intense politicking of committee members by applicants, their practice groups, and potential competitors. Consequently, some gastroenterologists upon completing standard fellowships train and learn ERCP 'on the job' during independent/unsupervised practice, which can result in bad outcomes: high rates of failed bile duct cannulation. This severe clinical problem is indicated by publication of ≥ 12 ERCP competency studies/guidelines during last 5 years. However, lack of mandatory, quantitative, ERCP credentialing criteria has permitted neglect of recommended guidelines. This work comprehensively reviews literature on ERCP credentialing;reviews rationales for proposed guidelines;reports problems with current system;and proposes novel criteria for competency. This work advocates for mandatory, national, written,minimum, quantitative, standards, including cognitive skills(possibly assessed by a nationwide examination), and technical skills, assessed by number performed(≥ 200-250 ERCPs), types of ERCPs, success rate(approximately ≥ 90%cannulation of desired duct), and letters of recommendation by program director/ERCP mentor. Mandatory criteria should ideally not be monitored by a hospital committee subjected to intense politicking by applicants, their employers, and sometimes even competitors, but an independent national entity,like the National Board of Medical Examiners/American Board of Internal Medicine. 展开更多
关键词 Endoscopic retrograde CHOLANGIOPANCREATOGRAPHY Privileges CREDENTIALING Gastroenterology FELLOWSHIP TRAINING Advanced gastrointestinal endoscopy TRAINING Certification standards
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Parasitic Contamination of Drinking Water and Egyptian Standards for Parasites in Drinking Water 被引量:2
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作者 Wafaa M. Hikal 《Open Journal of Ecology》 2020年第1期1-21,共21页
Water is life and access to clean drinking water is a fundamental human right. For human health, drinking water standards and guidelines have been developed to ensure their quality. Waterborne parasites are a great ch... Water is life and access to clean drinking water is a fundamental human right. For human health, drinking water standards and guidelines have been developed to ensure their quality. Waterborne parasites are a great challenge and cause many diseases for humans. Thus, continuous monitoring of drinking water from the competent authorities in search of pollutants is required. The safety of drinking water for the growing population can be ensured by the correct use of water treatment technologies. Cryptosporidium is the first parasite to cause concern to health officials in the world. Also, Naegleria fowleri causes fatal cerebral infection, Acanthamoeba species that cause both cerebral and corneal disease;and Giardia which has heightened world concerns because of its severity. This study is based on highlighting on drinking water quality guidelines and standards published by the World Health Organization and some countries, especially Egypt. A growing concern globally after the scientists revealed the effects of polluted drinking water. So, a large number of the population is at risk of water pollution for the purpose of human access to clean drinking water and other uses. 展开更多
关键词 Drinking Water standards ACANTHAMOEBA CRYPTOSPORIDIUM GIARDIA NAEGLERIA
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Ophthalmology residency training in Jordan:an evaluation of quality and comparison with international standards 被引量:1
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作者 Khalil M.Al-Salem Fawwaz A.Al-Sarayra +4 位作者 Mohammad Abu Al-Dabaat Wisam Shihadeh Mohammad M.Al-Salem Mahmoud K.Al-Salem Shlomit Schaal 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第5期898-904,共7页
AIM:To evaluate Jordanian ophthalmology residency programs in achieving competencies outlined by the International Council of Ophthalmology(ICO) and residents' satisfaction with available training programs in Jord... AIM:To evaluate Jordanian ophthalmology residency programs in achieving competencies outlined by the International Council of Ophthalmology(ICO) and residents' satisfaction with available training programs in Jordan, and to highlight weakness points that may be improved and strengthened.· METHODS:A closed-ended questionnaire was circulated to all ophthalmologists who completed their training in Jordanian institutions between 2006 and 2011,to measure the quality of residency training and satisfaction level with regards to clinical conferences,journal clubs, scientific lectures, wet lab sessions,simulations, outpatient clinics and operating room training. Barriers to a successful board exam were cited.All ophthalmologists had official residency training in Jordanian Hospitals; this includes military, university,governmental and private sector hospitals.RESULTS:Sixty-one questionnaires completed out of69 circulated. Males(75.4%) were more than females.Mean age was 32.5±3.27 y. A total 21(34.4%) responders expressed an overall satisfaction, 38(62.3%) were dissatisfied and 2(3.3%) were equivocal. Respondents reported insufficient exposure to low-vision rehabilitation57(93.4%),or refraction and glasses prescription 34(55.7%).Regarding operative experiences, the mean cataract extraction per-resident was 43 cataracts; the number of phacoemulsification surgery was 2.96 per-resident, 46(75.4%)of responders never did a single phacoemulsificationduring residency. Nine(14.8%) had training in refractive surgery, and 15(24.6%) assisted orbital surgery. Fortyfour(72.1%) never assisted in vitreoretinal surgery.Among The graduates surveyed, 14(23.0%) passed Jordanian licensing board exam at the first attempt, and felt that their residency programs adequately prepared them for the examinations.· CONCLUSION:Around two thirds(62.3%) of ophthalmologists expressed dissatisfaction with residency training at Jordanian programs, further study is required to assess each program separately and evaluate the system of accreditation in Jordanian residency programs. 展开更多
关键词 trainees’ PERSPECTIVES RESIDENCY training international standards
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Development of 0.5-V Josephson junction array devices for quantum voltage standards 被引量:1
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作者 王兰若 李劲劲 +2 位作者 曹文会 钟源 张钟华 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第6期453-457,共5页
The design, fabrication, and the characterization of a 0.5-V Josephson junction array device are presented for the quantum voltage standards in the National Institute of Metrology(NIM) of China. The device consists of... The design, fabrication, and the characterization of a 0.5-V Josephson junction array device are presented for the quantum voltage standards in the National Institute of Metrology(NIM) of China. The device consists of four junction arrays, each of which has 1200 3-stacked Nb/NbxSi1-x/Nb junctions and an on-chip superconducting microwave circuit which is mainly a power divider enabling each Josephson array being loaded with an equal amount of microwave power. A direct current(dc) quantum voltage of about 0.5 V with a ~1-mA current margin of the 1 st quantum voltage step is obtained.To further prove the quality of NIM device, a comparison between the NIM device with the National Institute of Standards and Technology(NIST) programmable Josephson voltage standard(PJVS) system device is conducted. The difference of the reproduced 0.5-V quantum voltage between the two devices is about 0.55 nV, which indicates good agreement between the two devices. With the homemade device, we have realized a precise and applicable 0.5-V applicable-level quantum voltage. 展开更多
关键词 JOSEPHSON voltage standards JOSEPHSON JUNCTION superconducting-normal metal–superconducting(SNS) JUNCTION QUANTUM device
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Different standards for healthy screenees than patients in routine clinics? 被引量:1
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作者 Geir Hoff 《World Journal of Gastroenterology》 SCIE CAS 2013年第46期8527-8530,共4页
Less than 5%of colorectal adenomas will become malignant,but we do not have sufficient knowledge about their natural course to target removal of these5%only.Thus,95%of polypectomies are a waste of time exposing patien... Less than 5%of colorectal adenomas will become malignant,but we do not have sufficient knowledge about their natural course to target removal of these5%only.Thus,95%of polypectomies are a waste of time exposing patients to a small risk of complications.Recently,a new type of polyps,sessile serrated polyps,has attracted attention.Previously considered innocuous,they are now found to have molecular similarities to cancer and some guidelines recommend to have them removed.These lesions are often flat,covered by mucous,not easily seen and situated in the proximal colon where the bowel wall is thinner.Thus,polypectomy carries a higher risk of perforation than predominantly left-sided,stalked adenomas-and we do not know what is gained in terms of cancer prevention.Screening is a neat balance between harms and benefit for presumptively healthy participants not interested in risk exposure to obtain confirmation of being healthy.The situation is quite different for patient worried about symptom.Thus,the standards set for evidence-based practice may be higher for screening than for routine clinics-a mechanism which may benefit patients in the long run. 展开更多
关键词 COLONOSCOPY Screening Quality ASSURANCE standards
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Computed Tidal Relativistic Red-Shifts of Frequency Standards on Earth and in Space Stations 被引量:2
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作者 庄伟 房芳 +2 位作者 王少凯 赵阳 李天初 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期11-14,共4页
Frequencies of frequency standards are shifted by the local static gravity red shifts and also modulated by the tidal relativistic red shifts. We compute the tidal relativistic red shifts using a time-domain method an... Frequencies of frequency standards are shifted by the local static gravity red shifts and also modulated by the tidal relativistic red shifts. We compute the tidal relativistic red shifts using a time-domain method and present the numerical results for the National Institute of Metrology(NIM) in Beijing, Laboratoire National de Metrologie et Essais-Systeme de References Temps-Espace(LNE-SYRTE) in Paris and Physikalisch-Technische Bundesanstalt(PTB) in Braunschweig. The differences of the tidal relativistic red shift approach as large as 1.1×10^(-16) when frequency standards at NIM are compared with those at SYRTE and PTB. Moreover, the tidal relativistic red shifts of frequency standards in space stations are also computed. 展开更多
关键词 Computed Tidal Relativistic Red-Shifts of Frequency standards on Earth and in Space Stations
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Development of an Ontology-Based Knowledge Network by Interconnecting Soil/Water Concepts/Properties, Derived from Standards Methods and Published Scientific References Outlining Infiltration/Percolation Process of Contaminated Water 被引量:1
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作者 Stephanos D. V. Giakoumatos Anastasios K. T. Gkionakis 《Journal of Geoscience and Environment Protection》 2021年第1期25-52,共28页
The present work deals with the development of an Ontology-Based Knowledge Network of soil/water physicochemical & biological properties (soil/water concepts), derived from ASTM Standard Methods (ASTMi,n) and rele... The present work deals with the development of an Ontology-Based Knowledge Network of soil/water physicochemical & biological properties (soil/water concepts), derived from ASTM Standard Methods (ASTMi,n) and relevant scientific/applicable references (published papers—PPi,n) to fill up/bridge the gap of the information science between cited Standards and infiltration discipline conceptual vocabulary providing accordingly a dedicated/internal Knowledge Base (KB). This attempt constitutes an innovative approach, since it is based on externalizing domain knowledge in the form of Ontology-Based Knowledge Networks, incorporating standardized methodology in soil engineering. The ontology soil/water concepts (semantics) of the developed network correspond to soil/water physicochemical & biological properties, classified in seven different generations that are distinguished/located in infiltration/percolation process of contaminated water through soil porous media. The interconnections with arcs between corresponding concepts/properties among the consecutive generations are defined by the relationship of dependent and independent variables. All these interconnections are documented according to the below three ways: 1) dependent and independent variables interconnected by using the logical operator “<em>depends on</em>” quoting existent explicit functions and equations;2) dependent and independent variables interconnected by using the logical operator “<em>depends on</em>” quoting produced implicit functions, according to Rayleigh’s method of indices;3) dependent and independent variables interconnected by using the logical operator “<em>related to</em>” based on a logical dependence among the examined nodes-concepts-variables. The aforementioned approach provides significant advantages to semantic web developers and web users by means of prompt knowledge navigation, tracking, retrieval and usage. 展开更多
关键词 INFILTRATION PERCOLATION ASTM standards Soil/Water Contamination Knowledge Base Ontology Network Semantics Porous Media
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