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计算机科学 1987年第1期 46-51页

作者： J.w.lloyd 伍丰富

本文对演绎数据库系统作了辅导性的介绍.这种系统的开发基本上是将逻辑程序设计思想和关系数据库的思想结合起来应用的.演绎数据库系统的精巧的理论框架由一阶逻辑提供.对于数据,程序,询问,视图和完整性约束,都把逻辑作为一种一致的语... 详细信息

本文对演绎数据库系统作了辅导性的介绍.这种系统的开发基本上是将逻辑程序设计思想和关系数据库的思想结合起来应用的.演绎数据库系统的精巧的理论框架由一阶逻辑提供.对于数据,程序,询问,视图和完整性约束,都把逻辑作为一种一致的语言来使用.本文强调指出,使用这些思想就能建造实际而有效的数据库系统.

关键词：演绎数据库关系数据库关系模型数据库数据库系统逻辑式程序设计逻辑程序设计

Sources and Trends of Persistent Organic Pollutants at Three Passive Monitoring Sites in South Africa

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Journal of Geoscience and Environment Protection 2020年第7期8卷 207-218页

作者： lloyd Shorai Pisa Nelson Mhlanga Patricia Mumbengengwi Department of Environmental Science and Technology Marondera University of Agricultural Sciences and Technology Marondera Zimbabwe Oakridge Sustainability Consulting Milton Keynes United Kingdom Department of Travel and Recreation Chinhoyi University of Technology Chinhoyi Zimbabwe

The Stockholm Convention on Persistent Organic Pollutants (SCPOPs) is an international treaty that operates under the patronage of the United Nations (UN) to control certain chemicals that are considered persistent organic pollutants (POPs). They are of great concern because of their adverse effects on human health and the environment. Exposure to POPs may lead to cancer, infertility, respiratory infections, and other health complications. It is therefore critical to study the degree of human and environmental exposure to these POPs. Passive air sampling was conducted in South Africa to evaluate the presence and trends of persistent organic pollutants at Barberspan (rural agricultural), Vanderbijl Park (urban industrial) and Molopo Nature Reserve (isolated nature reserve). Samples were collected in 2012. Passive air samplers using poly were used for sampling. The Buchi System B-811 automatic extractor was used to analyze for dichloro-diphenyl-trichlorethane (DDT), pentachlorobenzene (PeCB), hexechlorobenzene (HCB) polychlorinated biphenyls (PCBs) and hexachlorocyclohexane (HCH). Sampling was conducted for a period of one year. POPs concentrations were generally low at all sites, but Vanderbijl Park had the highest concentrations. Seasonal changes in concentrations were much the same at the three sites with temperatures and wind patterns being major factors. The presence of these chemicals in Molopo Nature Reserve and Barberspan is evidence of long range transportation over dry semi desert areas. Back-trajectories indicate possible sources, including areas where DDT is used for malaria control. The presence of POPs is areas they have never been in use poses health and environmental risks in these areas.

关键词： Persistent Organic Pollutants Passive Air Sampling Long Range Transportation

Applicability of a Surveillance Methodology for the Microbiological Safety of well water Supplies, in a Highly Vulnerable Hydrogeological Setting——A Case Study Based Findings from the west Coastal Area of Sri Lanka

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Journal of water Resource and Protection 2012年第11期4卷 899-912页

作者： Shivasorupy Barthiban Barry John lloyd Matthias Maier Centre for Environmental Health Engineering University of Surrey Surrey UK Stadtwerke Karlshruhe Karlshruhe Germany

A well surveillance study carried out in nine Divisional Secretariat Divisions on the west coast of Sri Lanka showed that 70.3% of 101 well sampling points were microbially contaminated with equal to, or greater than, faecal coliform grade C (11 - 100 cfu/100 mL). Due to the very vulnerable hydro-geological setting of the coastal sand, laterite and alluvium aquifers occurring in the study areas, the recommended safe separation distance between an on-site sanitation system and a well could not be achieved. Hence, a cardinal rule of well protection was observed to be broken at almost every well study site. The existing excreta disposal systems need to be improved or replaced with more efficient ones before the impact of other sanitary hazards at the well, and wellhead area, on the microbial quality of well water, can be determined and addressed. The published (wHO, 1997) sanitary survey forms for open dug wells and tube wells need to be modified in the context of the study areas described. Based on a comparison of three different statistical methods used to assess the relative significance of each sanitary hazard modification to the methodology for determining the sanitary hazard index (SHI) was prescribed.

关键词： Surveillance of wells Faecal Coliform Counts Sanitary Survey Sanitary Hazard Score

Tuning and Cold Test of a Four-Vane RFQ with Ramped Inter-Vane Voltage for the Compact Pulsed Hadron Source

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Chinese Physics Letters 2013年第5期30卷 48-51页

作者： XING Qing-Zi DU Lei ZHENG Shu-Xin GUAN Xia-Ling LI Jian CAI Jin-Chi GONG Cun-Kui wANG Xue-wu TANG Chuan-Xiang James Billen James Stovall lloyd Young Key Laboratory of Particle&Radiation Imaging(Ministry of Education) Tsinghua UniversityBeijing 100084 NUCTECH Co.Ltd. Beijing 100084 3905 Circle Drive Los AlamosNM 87544USA Rutherford Appleton Laboratory Harwell OxfordDidcot OX110QXUK LMY Technology 1469 Plantation CircleLincolntonGA 30817USA

A four-vane radio-frequency quadrupole(RFQ)accelerator is under construction for the Compact Pulsed Hadron Source(CPHS)project at Tsinghua *** 3 m-long RFQ will accelerate a 50 keV proton beam from the ECR source to 3 MeV,and deliver it to the downstream drift tube linac(DTL)with a peak current of 50 mA,pulse length of 0.5 ms and beam duty factor of 2.5%.The inter-vane voltage is designed to increase with the longitudinal position to produce a short *** plates are therefore not *** cavity cross section and vane-tip geometry are tailored as a function of the longitudinal position,while limiting the peak surface electric field to 1.8 *** RFQ is designed,manufactured,and installed at Tsinghua *** also present the tuning and cold test results of the RFQ *** final tuning,the relative error of the quadrupole field is within 2%,and the admixture of the two dipole modes are less than 2%of the quadrupole mode.

关键词： beam Van cavity

High yield reproducible rat model recapitulating human Barrett's carcinogenesis

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world Journal of Gastroenterology 2017年第33期23卷 6077-6087页

作者： Daisuke Matsui Ashten N Omstead Juliann E Kosovec Yoshihiro Komatsu Emily J lloyd Hailey Raphael Ronan J Kelly Ali H Zaidi Blair A Jobe Esophageal and Lung Institute Allegheny Health Network Department of Gastroenterological Surgery Kanazawa University Hospital Department of Oncology Sidney Kimmel Comprehensive Cancer CenterJohns Hopkins Hospital

AIM To efficiently replicate the biology and pathogenesis of human esophageal adenocarcinoma(EAC) using the modified Levrat model of end-to-side esophagojejunostomy. METHODS End-to-side esophagojejunostomy was performed on rats to induce gastroduodenoesophageal reflux to develop EAC. Animals were randomly selected and serially euthanized at 10(n = 6),17(n = 8),24(n = 9),31(n = 6),38(n = 6),and 40(n = 6) wk postoperatively. The esophagi were harvested for downstream histopathology and gene expression. Histological evaluation wascompleted to determine respective rates of carcinogenic development. Quantitative reverse transcriptionpolymerase chain reaction was performed to determine gene expression levels of MUC2,CK19,and CK20,and results were compared to determine significant differences throughout disease progression *** The overall study mortality was 15%. Causes of mortality included anastomotic leak,gastrointestinal hemorrhage,stomach ulcer perforation,respiratory infection secondary to aspiration,and obstruction due to tumor or late anastomotic stricture. 10 wk following surgery,100% of animals presented with esophagitis. Barrett's esophagus(BE) was first observed at 10 wk,and was present in 100% of animals by 17 wk. Dysplasia was confirmed in 87.5% of animals at 17 wk,and increased to 100% by 31 wk. EAC was first observed in 44.4% of animals at 24 wk and increased to 100% by 40 wk. In addition,two animals at 38-40 wk post-surgery had confirmed macro-metastases in the lung/liver and small intestine,respectively. MUC2 gene expression was progressively down-regulated from BE to dysplasia to EAC. Both CK19 and CK20 gene expression significantly increased in a stepwise manner from esophagitis to EAC. CONCLUSION Esophagojejunostomy was successfully replicated in rats with low mortality and a high tumor burden,which may facilitate broader adoption to study EAC development,progression,and therapeutics.

关键词： Esophageal adenocarcinoma gastroeso phageal reflux disease Levrat Esophagojejunostomy Experimental rat model Mucin genes Cytokeratins

Two New Species of Sciomyzidae (Diptera)from Palaearctic China

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Entomotaxonomia 1991年第1期13卷 65-70页

作者： Rudolf ROZKOSNY lloyd KNUTSON 捷克J.E.Purkyne大学自然科学学院美国农业部农业研究局欧州杂草生物防治实验室意大利罗马

Two new species of Sciomyzidae from Manchuria (Northeastern China) are described. Pherbellia orientalis sp. n. belongs to the P. dorsata group and is characterized by partly darkened wings and a contrasting white fore basitarsus. Elgiva manchurica sp. n. is apparently related to E divisa (Loew) but differs by the bare prosternum and differently shaped structures of the male genitalia.

关键词： Taxonomy Pherbillia orientalis sp. n. Elgiva manchurica sp. n. Manchuria

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Towards Sustainable Development–Recommendation of Actions for Geoparks

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Journal of Geographical Sciences 2012年第6期22卷 1149-1151页

作者：蔚东英 James wILSON lloyd RICHARDSON Carole MURPHY 王民刘昌明 School of Geography Beijing Normal University University of Missouri-Saint Louis

From 27th to 29th, May, 2011, the participants of the 2nd International Forum on Geoparks from 5 countries gathered in Taining, Fujian Province, China. The participants discussed developing and preserving our Geoparks and Geo-heritage in sustainable ways. The forum recognized that the Geopark Program initiated by UNESCO is an efficient tool for geo-heritage protection, recreation, education and economic development. The role of capacity building in achieving sustainable development of Geoparks is significant and the potential for caoacitv building has not been fullv realized.

关键词： Local Artisan Visitor Facility Include water Quality Educational Capacity Innovative Educational Program

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Building the Capacity of Schools to Improve the Health of Nations

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Building the Capacity of Schools to Improve the Health of Na...

生油岩评价中T_(max)的抑制:资料及修正

文明的和谐与共同繁荣：全球化视野中亚洲的机遇与发展——北京论坛（2005）

作者： lloyd J.Kolbe Indiana University

Introduction Humankind has entered a new *** November,2005,the U.S. Centers for Disease Control and Prevention counted 50 emerging and reemerging communicable diseases,as listed in Table *** these,and other equally fo...

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国外油气勘探 1996年第5期8卷 563-567,625页

作者： lloyd R.Snowdon 吴爱平青海石油管理局勘探开发研究院

生油岩评价中(Rock-Eval)热成熟参数(T_(max))相对于围岩可能偶而被抑制。普遍认为这是由于沥青对S_2峰的作用,或者由于富硫(和因此产生热不稳定性)干酪根存在的结果。这种现象常常伴随着高自然伽马射线特征及上升的Rock-Eval氢指数(HI... 详细信息

生油岩评价中(Rock-Eval)热成熟参数(T_(max))相对于围岩可能偶而被抑制。普遍认为这是由于沥青对S_2峰的作用,或者由于富硫(和因此产生热不稳定性)干酪根存在的结果。这种现象常常伴随着高自然伽马射线特征及上升的Rock-Eval氢指数(HI)和总有机碳(TOC)含量。这种热成熟度的确定取决于对围岩T_(max)进行内插或直接估算特定样品的抑制范围。如果现有样品仅限于常规或代表有限地层层段的井壁岩心材料,则可能需要直接估算特定样品的抑制范围。艾伯塔盆地的Second white Speckled页岩(白垩系科罗拉多组的一部分)在其部分厚层段显示出T_(max)抑制现象。通过计算在不同热成熟度水平的几口井中作为TOC和HI的线性回归函数的T_(max)值,发现有一定的一致性。在约453℃(晚生油窗)以下,HI每增加50mg HC/g TOC,T_(max)约抑制1℃。因此,通过外推所有的T_(max)值至HI为100～150mg HC/g TOC(Ⅲ型干酪根典型值)的稳定区,可校正Second white Speckled页岩中的T_(max)抑制。

关键词：生油岩样品热成熟度储集层

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