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Direct evidence of microbiological water quality changes on bacterial quantity and community caused by plumbing system

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Journal of Environmental Sciences 2022年第6期34卷 175-183页

作者： Jun Li Anran Ren ed van der Mark Gang Liu Key Laboratory of Drinking water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Dunea water Company Plaza of the United Nations 11-15Zoetermeer 2700 ATthe Netherlands Sanitary engineering Department of Water managementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GAthe Netherlands

Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate(ATP) and the microbial community was profiled by 454 *** results showed that in distribution pipes, biofilm contributed >94% of the total biomass,while loose deposits showed little contribution(water had minor effects on the microbiocidal water quality regarding both quantity(ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass(1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap(22%) was higher than that at water main(2%), while the relative abundance of Pseudomonas spp. in tap water(15%) was lower than that in the water from street water main(29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.

关键词： Drinking water distribution system Plumbing system Microbiological water quality Sampling program 454 pyrosequencing

Global research trends on diet and nutrition in Crohn’s disease

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World Journal of Gastroenterology 2023年第20期29卷 3203-3215页

作者： Muna Shakhshir Sa'ed H Zyoud Department of Nutrition An-Najah National University HospitalNablus 44839Palestine Department of Clinical and Community Pharmacy College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Poison Control and Drug Information Center(PCDIC) College of Medicine and Health SciencesAn-Najah National UniversityNablus 44839Palestine Clinical Research Centre An-Najah National University HospitalNablus 44839Palestine

BACKGROUND Crohn’s disease represents a challenge for patients concerned with the modified diet regimen as well as practitioners who seek the best nutritional ***’s disease can alter the body’s ability to digest food and to absorb nutrients,resulting in severe vitamin deficiencies,malnutrition and sometimes lifethreatening ***,a comprehensive bibliometric analysis is lacking to map the current links between nutrition and Crohn’s disease in terms of the number of citations,geographic distribution and growth trends of *** To introduce the current state of research as well as hotspots in the field of nutrition and Crohn’s disease from a bibliometric *** We searched the Scopus database and selected the relevant literature on nutrition and Crohn’s disease that met the inclusion *** analyzed the publication trends and research hotspots by using video object segmentation viewer *** We included 1237 *** number of documents published each year has increased *** United States and the University of Otago,Christchurch,have had the highest productivity,with 208(16.81%)and 29(2.34%)documents,***“role of exclusive enteral nutrition for complicated Crohn’s disease”and“manipulation of the gut microbiota as a key target for Crohn’s disease”were the major research areas in 2016-2021,and they could be extensively investigated in the ***,research on“malnutrition in patients with Crohn’s disease”appeared to be an area that attracted more research attention before *** This is the first bibliometric analysis to map the knowledge structure and trends regarding nutrition in Crohn’s disease research over the past two *** results provide a comprehensive summary and identification of the frontiers of nutrition and Crohn’s disease-related research,which may be used as a resource by researchers in the field.

关键词： Nutrition Diet Crohn’s disease Bibliometric Microbiota Malnutrition

Fluid flow and heat transfer characteristics of spiral coiled tube: Effects of Reynolds number and curvature ratio

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Journal of Central South University 2012年第2期19卷 471-476页

作者： YOO Geun-jong CHOI Hoon-ki DONG wa-ryong School of Mechatronics Changwon National University

Numerical analysis was performed to investigate flow and heat transfer characteristics in spiral coiled tube heat exchanger. Radius of curvature of the spiral coiled tube was gradually increased as total rotating angle reached 12n. As the varying radius of curvature became a dominant flow parameter, three-dimensional flow analysis was performed to this flow together with different Reynolds numbers while constant wall heat flux condition was set in thermal field. From the analysis, centrifugal force due to curvature effect is found to have significant role in behavior of pressure drop and heat transfer. The centrifugal force enhances pressure drop and heat transfer to have generally higher values in the spiral coiled tube than those in the straight tube. Even then, friction factor and Nusselt number are found to follow the proportionality with square root of the Dean number. Individual effect of flow parameters of Reynolds number and curvature ratio was investigated and effect of Reynolds number is found to be stronger than that of curvature effect.

关键词： spiral coiled tube heat exchanger Reynolds number curvature ratio secondary flow friction factor Nusselt number

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重组大肠杆菌全细胞转化苹果酸合成丙酮酸

中国食品学报 2024年第7期24卷 219-228页

作者：付声亮邹诗瑶高娃赵筱王金华王永泽工业发酵省部共建协同创新中心武汉430068 湖北省工业微生物重点实验室武汉430068 湖北工业大学生物工程与食品学院武汉430068

拟建立一条以苹果酸为原料,通过大肠杆菌全细胞转化获得丙酮酸的合成途径。以大肠杆菌BL21(DE3)为宿主,在pET28a上共表达内源的苹果酸酶(ME)和来自博伊丁假丝酵母(Candida boidinii)的醛糖还原酶(AR),并对细胞浓度、底物浓度、温度和pH... 详细信息

拟建立一条以苹果酸为原料,通过大肠杆菌全细胞转化获得丙酮酸的合成途径。以大肠杆菌BL21(DE3)为宿主,在pET28a上共表达内源的苹果酸酶(ME)和来自博伊丁假丝酵母(Candida boidinii)的醛糖还原酶(AR),并对细胞浓度、底物浓度、温度和pH值等催化关键因素进行研究。共表达后大肠杆菌苹果酸酶和博伊丁假丝酵母醛糖还原酶酶活分别为(2.8±0.21),(3.1±0.34)U/mL。适宜的催化条件为:细胞浓度OD600nm值为30,底物苹果酸质量浓度为30 g/L,木糖和苹果酸物质的量比为1.0,温度为40℃,反应体系pH值为7.8,丙酮酸产量最高可达23.16 g/L。本研究为生物法合成丙酮酸提供了一种新的方法。

关键词：丙酮酸全细胞催化苹果酸苹果酸酶醛糖还原酶

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Cutaneous Metastases Arising from Synovial Sarcoma： A Case Report

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Chinese Medical Journal 2017年第24期130卷 3019-3020页

作者： Xue Zeng Li Li wa-Li Liu Department of Dermatology Guang'anmen Hospital China Academy of Chinese Medical Sciences Beijing 100053 China Department of Dermatopathology Guang'anmen Hospital China Academy of Chinese Medical Sciences Beijing 100053 China

To the editor：Synovial sarcoma （SS） is a relatively rare type of soft tissue sarcoma that constitutes approxima.ely 8% of all soft tissue *** frequently occurs in the para-articular structures of the limbs and is predominantly found in the lower *** other involved locations of invasion are lung,lymph nodes,and ***,the skin is rarely involved.[1-3] Here,we reported an extremely rare case ofbiphasic SS presenting with disseminated cutaneous metastases.

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NuMDG:A New Tool for Multiway Decision Graphs Construction

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Journal of Computer Science & Technology 2011年第1期26卷 139-152页

作者： Sa'ed Abed Yassine Mokhtari Otmane Ait-Mohamed Sofiene Tahar Department of Computer Engineering Hashemite UniversityZarqaJordan Department of Electrical and Computer Engineering Concordia UniversityMontrealCanada

Multiway Decision Graphs （MDGs） are a canonical representation of a subset of many-sorted first-order logic. This subset generalizes the logic of equality with abstract types and uninterpreted function symbols. The distinction between abstract and concrete sorts mirrors the hardware distinction between data path and control. Here we consider ways to improve MDGs construction. Efficiency is achieved through the use of the Generalized-If-Then-Else （GITE） commonly operator in Binary Decision Diagram packages. Consequently, we review the main algorithms used for MDGs verification techniques. In particular, Relational Product and Pruning by Subsumption are algorithms defined uniformly through this single CITE operator which will lead to a more efficient implementation. Moreover, we provide their correctness proof. This work can be viewed as a way to accommodate the ROBBD algorithms to the realm of abstract sorts and uninterpreted functions. The new tool, called NuMDG, accepts an extended SMV language, supporting abstract data sorts. Finally, we present experimental results demonstrating the efficiency of the NuMDG tool and evaluating its performance using a set of benchmarks from the SMV package.

关键词： infinite state model checking multiway decision graphs uninterpreted functions

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editorial

Science China(Physics,Mechanics & Astronomy) 2009年第12期52卷 1813-1814页

作者： Ping JinSong Qian ZhiHan Fung Lai-wa Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai200030China

Since the 1990s, a new round of lunar exploration missions have aroused profound interest of such big aerospace nations as U.S., Japan, Europe, China and India in broad-based active participation. In

关键词： VLBI editorial CE

Eutrophication Process of Soil nearby a Sanitary Landfill and Its Influence on Brazilian Savanna Vegetation

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Journal of Environmental Protection 2022年第5期13卷 344-359页

作者： Otacílio Antunes Santana José ima.a-Encinas Department of Biofísic and Radiobiology Rural University of Pernambuco Recife Brazil Department of Forestry University of Brasília Brasília Brazil

This work aimed to demonstrate if exists a relation between eutrophic processes of soil (N, P, K, pH, and organic matter) with phytosociology mosaic of native tree species in Brazilian adjacent sanitary landfill areas of the savanna. One of the study area is located in Brasilia, Federal District, and the other one in Goiania, State of Goiás, 210 km far each other. The methodology consisted in techniques, procedures and specific software applied to this kind of data. There were used plots and subplots for each area and for the vegetation and soil survey. Statistical significance showed that there exists a relationship between eutrophic processes of soil with phytosociology mosaic of native savanna tree species.

关键词： Native Tree Species Savanna Network Neural Model Nutrients

Diametric Structure of One Fragment of One Deciduous Seasonal Forest in Brazilian Savanna Eco Museum

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Journal of Environmental Protection 2023年第6期14卷 470-480页

作者： José ima.a-Encinas Otacílio Antunes Santana Department of Forestry University of Bras&iacutelia Bras&iacutelia Brazil Department of Biofí sic and Radiobiology Rural University of Pernambuco Recife Brazil

A 10 ha deciduous seasonal forest fragment (15°45'54''S and 49°04'03''W) found in the bioregion of the Savanna Eco Museum localized in the state of Goiás, Brazil was studied. For the phytosociological survey, 10 sample plots of 20 × 20 m were systematically located. All living trees of 5 cm DBH and above were measured with the plot boundaries. There were 742 individuals belonging to 83 species and 38 families. The richest families in terms of the number of species were Leguminosae, Rubiaceae, Myrtaceae, Apocynaceae and Chrisobalanaceae, which contributed 48% of the total species. The species with the highest importance value indices (IVI) were Tapira quianensis (Aubl.), Protium heptaphyllum (Aubl.) March., Callisthene mayor (Mart.), Amaioua guianensis (Aubl.) and Anadenanthera macrocarpa (Benth.) Brenan. The Shannon diversity index was 3.80 nats/individuals and the Pielou equality index was 0.86 for the total population. 549 sampled trees had DBH values lower than 30 cm. This indicates that this forest has a high potential for natural succession. Two DBH distributions were observed: the typical reverse “J”, described frequently in the literature, and a nearly Gaussian distribution.

关键词： Native Tree Species Diametric Distribution Phytosociological Survey