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Effects of Carbon Content and Solidification Rate on the Thermal Conductivity of Grey Cast Iron

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Tsinghua Science and Technology 2008年第2期13卷 170-176页

作者： Daniel Holmgren Attila Diószegi ingvar l. svensson Department of Mechanical Engineering and Component Technology Jnkping University

The thermal conductivity/diffusivity of pearlitic grey irons with various carbon contents was investigated by the laser flash method. The materials were cast in controlled thermal environments producing three dissimilar cooling rates. The cooling rates together with the carbon content largely influence the thermal conductivity of grey iron. linear relationships exist between the thermal conductivity and the carbon content, the carbon equivalent, and the fraction of the former primary solidified austenite transformed into pearlite. The results show that the optimal thermal transport properties are obtained at medium cooling rates. Equations are given for the thermal conductivity of pearlite, solidified as pre-eutectic austenite, and the eutectic of grey iron. The thermal conductivity of pearlitic grey iron is modelled at both room temperature and elevated temperatures with good accuracy.

关键词： grey iron thermal conductivity thermal diffusivity carbon content carbon equivalent color etching graphite morphology eutectic cell size

An algorithm for family screening for coeliac disease

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World Journal of Gastroenterology 2006年第48期12卷 7805-7809页

作者： Jocelyn S Fraser Alistair l King H Julia Ellis Simon J Moodie ingvar Bjarnason Jill Swift Paul J Ciclitira Division of Nutritional Sciences King's College London United Kingdom Division of Nutritional Sciences King’s College London United Kingdom

AIM: To assess the level of undiagnosed coeliac disease (CD) in relatives of patients affected by the condition. METHODS: We collected blood from 914 relatives of probands. We screened these individuals by ElISA for IgA and IgG tTG antibodies, confirming any positive IgA tTG results with an IgA EMA and looked for evidence of IgA deficiency in those who were IgG tTG positive alone, and performed IgG1 EMA in these individuals. We undertook HlA typing where positive screening was found, and this confirmed a strong prevalence of HlA- DQ2 in the coeliac population. Follow-up small intestinal biopsy was undertaken in cases with positive serological screening, wherever possible. RESUlTS:Use of this serological screening algorithm revealed a prevalence of undiagnosed CD in 5%-6% of first degree relatives of probands. CONClUSION:Our data suggests that first degree relatives of individuals with CD should be screened for this condition.

关键词： Coeliac disease Screening Endomysialantibody Familial study IgA deficiency Prevalence Tissue transglutaminase

Size matters:the biochemical logic of ligand type in endocrine crosstalk

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life Metabolism 2024年第1期3卷 10-20页

作者： Jameel Barkat lone Jonathan Z.long Katrin J.svensson Department of Pathology Stanford University School of MedicineStanfordCA 94305United States Department of Chemistry Stanford UniversityStanfordCA 94305United States Stanford Diabetes Research Center Stanford University School of MedicineStanfordCA 94305United States Sarafan ChEM-H Stanford UniversityStanfordCA 94305United States Wu Tsai Human Performance Alliance Stanford UniversityStanfordCA 94305United States Stanford Cardiovascular Institute Stanford University School of MedicineCA 94305United States

The endocrine system is a fundamental type of long-range cell-cell communication that is important for maintaining metabolism,physiology,and other aspects of organismal *** signaling is mediated by diverse blood-borne ligands,also called hormones,including metabolites,lipids,steroids,peptides,and *** size and structure of these hormones are fine-tuned to make them bioactive,responsive,and adaptable to meet the demands of changing *** has nature selected such diverse ligand types to mediate communication in the endocrine system?What is the chemical,signaling,or physiologic logic of these ligands?What fundamental principles from our knowledge of endocrine communication can be applied as we continue as a field to uncover additional new circulating molecules that are claimed to mediate long-range cell and tissue crosstalk?This review provides a framework based on the biochemical logic behind this crosstalk with respect to their chemistry,temporal regulation in physiology,specificity,signaling actions,and evolutionary development.

关键词： endocrine ligand size metabolites signaling evolution

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瑞典泥炭开采区的CH_4和CO_2通量

AMBIO－人类环境杂志 2000年第8期29卷 499-503,517页

作者： ingvar Sundh Mats Nilsson Catharina Mikkel Gunnar Granberg Bo svensson 陶波王绍强瑞典农业科学大学微生物学系的助理教授瑞典农业科学大学获得林业生态学博士学位森林生态学博士学位土壤学博士学位微生物学博士学位

排水和泥炭开采可能引起泥炭地CH_4和CO_2等温室气体向大气中的排放量发生相当大的变化。在本研究中,我们采用密闭箱方法(closed chamber)测量了瑞典6个正在开采的泥炭地的CH_4和CO_2通量。结果显示,在沟渠测得的CH_4通量要比矿区条地(s... 详细信息

排水和泥炭开采可能引起泥炭地CH_4和CO_2等温室气体向大气中的排放量发生相当大的变化。在本研究中,我们采用密闭箱方法(closed chamber)测量了瑞典6个正在开采的泥炭地的CH_4和CO_2通量。结果显示,在沟渠测得的CH_4通量要比矿区条地(strips)高得多,例如,大部分泥炭地的CH_4排放量来自于沟渠。在生长季期间,这些泥炭地的CH_4排放总量(0.41～4.5g/m^2·a)与处于原始状态的泥炭地的情况相似。通过清除沟渠植被,可以使其CH_4的排放量保持较低水平。与CH_4的情况相似,在大多数泥炭地,矿区条地和沟渠都向大气中排放CO_2。在生长季节的排放量(0.23～1.0kg CO_2/m^2·a)主要是由矿区条地造成的。与采矿期间总的泥炭产量相比较而言,这些CO_2排放速率意味着:平均来说,泥炭地约6%的碳流失是由沼泽中微生物分解造成的。

关键词：瑞典泥炭开采区甲烷二氧化碳通量温室气体

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胸主动脉假性动脉瘤的外科治疗

世界核心医学期刊文摘（心脏病学分册） 2006年第12期2卷 59-60页

作者： Atik F.A. Navia J.l. svensson l.G. 张步升 Department of Thoracic and Cardiovascular Surgery The Cleveland Clinic Foundation Cleveland OH United States Dr.

Objectives: To examine the clinical profiles, operative outcomes, and late results of patients with pseudoaneurysm of the thoracic aorta. Methods: From 1990 to 2002, 60 patients underwent repair of aortic pseudoaneurysm: ascending aorta in 70%, ascending aorta and arch in 15%, descending aorta in 10%, and arch alone in 5%. Mean age was 53±15 years, and 70%were men. Of these, 50(83%) had undergone previous cardiac surgery, including 22(37%) composite valve graft operations. The preferred cannulation site was femoral-femoral(n=27, 45%), with deep hypothermic circulatory arrest in 62%and retrograde cerebral perfusion in 33%; more recently, however, axillary cannulation has been preferred. Results: Principal etiologies were graft infection in ascending aorta pseudoaneurysm and trauma in descending aorta pseudoaneurysm. Fifteen patients(25%) presented with chest pain, 13(22%) with heart failure, and 20%with moderate or severe aortic regurgitation. The pseudoaneurysm was resected and the aorta replaced(n=45, 75%) or repaired(n=15, 25%) using various methods. Hospital mortality was 6.7%(n=4). Reexploration for bleeding was required in 8.3%, and 3.3%had postoperative stroke. At 30 days, 5 years, and 10 years, survival was 94%, 74%, and 60%and freedom from reoperation was 95%, 77%, and 67%, respectively. Conclusions: Most patients with aortic pseudoaneurysm require ascending aorta and/or arch replacement, which can be accomplished with low operative mortality and morbidity. long-term survival and freedom from reoperation in these young patients parallel those expected for complex cardiac and aortic disease.

关键词：主动脉假性动脉瘤患者升主动脉主动脉升部

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偏航地球敏感器工程模型

控制工程（北京） 1999年第2期 22-34,63页

作者： svensson l.B.M. lindau S. Bjureus P.B. Hansson S. Agoston A. 郑克隆

一种工作在可见光波段的对地静止轨道卫星高精度偏航地球敏感器工程模型已经开发、设计、制造成功。这种偏航敏感器是一种功能完备的自主地球敏感器,它不需要外接CPU总线就可完成计算,定姿算法已经开发出来,并用气象卫星地球图象进行了... 详细信息

一种工作在可见光波段的对地静止轨道卫星高精度偏航地球敏感器工程模型已经开发、设计、制造成功。这种偏航敏感器是一种功能完备的自主地球敏感器,它不需要外接CPU总线就可完成计算,定姿算法已经开发出来,并用气象卫星地球图象进行了试验性验证,这种偏航敏感器包括一个独特而新颖的8位×256×256矩阵探测器IVP-MAPP 2200,它使敏感器变得非常紧凑。算法以图象处理与匹配技术为基础。计算偏航角之前,必须先算出俯仰与滚动角。然后改变卫星位置,使地球像能够处于敏感器芯片中心。敏感器要处理五种地球照明情况:全球照明、半球照明、新月形照明、新月形照明且太阳在视场中、地球完全无照明。在白天,全球照明与半球照明情况下,敏感器搜索地面控制点(GCP),用相关算法计算偏航角。在停晚和夜里,敏感器根据新月形地球的形心与表值相比较来计算偏航角。俯仰与滚动角测量精度为0.015°(全地球照明),偏航角测量精度为0.03°(增量精度)和0.2 °～ 0.5°(绝对精度),具体值视能够见到的地球照明面积而定。太阳在视场中出现,这是这种敏感器的一个潜在问题,因为动态范围太大会产生像晕效应,而有杂散光与叠影则会产生光学问题。不过,当太阳出现在视场中时,可以用降低俯仰与滚动角测量精度的办法来处理。如果看不见地球而只有太阳位置参与计算,就与其他模式相比较。在这种模式下,偏航角计算精度与采样数目有关,当卫星运动参数已知时,必须用多次采样确定太阳像的速度向量。

关键词：偏航地球敏感器设计测试工程模型敏感器

Mobilizing Crop Biodiversity

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Molecular Plant 2020年第10期13卷 1341-1344页

作者： Susan McCouch Zahra Katy Navabi Michael Abberton Noelle l.Anglin Rosa lia Barbieri Michael Baum Kirstin Bett Helen Booker Gerald l.Brown Glenn J.Bryan luigi Cattivelli David Charest Kellye Eversole Marcelo Freitas Kioumars Ghamkhar Dario Grattipaglia Robert Henry Maria Cleria Valadares Inglis Tofazzal Islam Zakaria Kehel Paul J.Kersey Graham J.King Stephen Kresovich Emily Marden Sean Mayes Marie Noelle Ndjiondjiop Henry T.Nguyen Samuel Rezende Paiva Roberto Papa Peter W.B.Phillips Awais Rasheed Christopher Richards Mathieu Flouard Maria Jose Amstalden Sampaio Uwe Scholz Paul D.Shaw Brad Sherman S.Evan Staton Nils Stein Jan svensson Mark Tester Jose Francisco Montenegro Valls Rajeev Varshney Stephen Visscher Eric von Wettberg Robbie Waugh Peter Wenzl loren H.Rieseberg Plant Breeding and Genetics School of Integrated Plant SciencesCornell UniversityIthacaNY14853USA DivSeek Global Institute for Food Security110 Gymnasium PlaceUniversity of SaskatchewanSaskatoonSKS7N 0W9Canada lnternational Institute of Tropical Agriculture(IITA) PMB 5320Oyo RdIbadanNigeria International Potato Center(CIP)1895 Avenida la Molina Lima Peru 12Lima 15023Peru Embrapa Genetic Resources and Biotechnology Parque Estacjao BiologicaFinal Av W5 NorteCaixa Postal 0237270770-917-Brasilia DFBrazil International Center for Agricultural Research in the Dry Areas(I CAR DA) Station Exp.INRA-Quich.Rue Hafiane Cherkaoui.Agdal.Rabat-Instituts10111RabatMorocco Department of Plant Sciences University of Saskatchewan51 Campus Dr.SaskatoonSK S7N 5A8Canada Department of Plant Agriculture University of GuelphRm 316Crop Science Bldg50 Stone Rd EGuelphON N1G 2W1Canada Genome Prairie 111 Research DriveSuite 101SaskatoonSKS7N 3R2Canada The James Hutt on Institute Errol RoadInvergowrieDundeeDD25DAUK CREA Research Centre for Genomics and Bioinformaticsvia San Protaso 302Fiorenzuola d'Arda29017Italy Genome British Columbia 400-575 West 8th AvenueVancouverBCV5Z 0C4Canada International Wheat Genome Sequencing Consortium 2841 NE Marywood CtLee's SummitMO.64086USA Forage Science Grasslands Research CentreAgResearchPalmerston North4410New Zealand Queensla nd Alliance for Agriculture and Food Inn ovation University of QueenslandBrisbaneQLD 4072Australia Institute of Biotechnology and Genetic Engineering(IBGE) Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh Southern Cross University PO Box 157LismoreNSW 2480Australia Royal Botanic Gardens KewRichmondSurreyTW93AEUK Feed the Future Innovation lab for Crop Improvement 431 Weill HallCornell UniversityIthacaNY14853USA Department of Botany and Biodiversity Research Centre University of British ColumbiaVancouverBC V6R 2A5Canada Crops For the Future(UK)CIC 76-80 Baddow Road ChelmsfordEs

Over the past 70 years,the world has witnessed extraordinary growth in crop productivity,enabled by a suite of technological advances,including higher yielding crop varieties,improved farm management,synthetic agrochemicals,and agricultural *** this"Green Revolution"intensified crop production,and is credited with reducing famine and malnutrition,its benefits were accompanied by several undesirable collateral effects(Pingali,2012).These include a narrowing of agricultural biodiversity,stemming from increased monoculture and greater reliance on a smaller number of crops and crop varieties for the majority of our *** reduction in diversity has created vulnerabilities to pest and disease epidemics,climate variation,and ultimately to human health(Harlan,1972).

关键词： intensified crops agricultural

血管紧张素转换酶抑制剂和血管紧张素受体拮抗剂的使用与2019冠状病毒疾病检测阳性之间的关系

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中华高血压杂志 2020年第5期28卷 499-499页

作者： Mehta N KalraA Nowacki AS Anjewierden S Han Z Bhat p Rubio AEC Jacob M Procop GW Harrington S Milinovich A svensson lG Jehi l Young JB Chung MK 周卫(译) 叶鹏(校) 不详

血管紧张素转换酶抑制剂(angiotensin-converting enzyme inhibitor,ACEI)和血管紧张素受体拮抗剂(angiotensin receptor blocker,ARB)在2019新型冠状病毒疾病(coronavirus disease 2019,COVID-19)全球大流行背景下的作用备受争议。此... 详细信息

关键词：血管紧张素受体拮抗剂血管紧张素转换酶抑制剂疾病检测冠状病毒 angiotensin 慢性病

采用有机朗肯循环废热回收的轻度混合动力火花点火涡轮增压轿车柴油机

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汽车与新动力 2020年第6期3卷 41-47页

作者： [瑞典]F.B.EKSTROM [瑞典]O.ROlANDSON [瑞典]S.ERIKSSON [瑞典]C.ODENMARCK [瑞典]M.svensson [瑞典]A.ERIKSSON [瑞典]H.OlSEN 闫红梅(译) 不详

汽车制造商在努力制造更节油的车辆时,会考虑采取一切可能的措施来提高内燃机动力系统的效率。其中,48V轻度混合动力技术即是节油措施之一。采用米勒技术的火花点火直喷发动机和从发动机废热中回收能量也是节油措施的一种。研究沃尔沃... 详细信息

汽车制造商在努力制造更节油的车辆时,会考虑采取一切可能的措施来提高内燃机动力系统的效率。其中,48V轻度混合动力技术即是节油措施之一。采用米勒技术的火花点火直喷发动机和从发动机废热中回收能量也是节油措施的一种。研究沃尔沃轿车基于乙醇的有机朗肯循环废热回收系统,围绕4缸2.0l的火花点燃发动机成功构建,运用48V轻度混合动力技术的同时考虑了车辆的安装需求。本研究还为有机朗肯循环系统开发了专用的控制系统,包括其与发动机之间的通信。有机朗肯循环系统使用发动机废气作为热源,为此设计制造专用的蒸发器以适合车辆的腔道。乙醇蒸气的膨胀发生在轴向活塞式膨胀机中,该轴向活塞式膨胀机通过皮带传动,既与混合动力系统电气耦合,又与发动机曲轴机械耦合。研究发现,该膨胀机的这种双重动力输出对于具有瞬态驾驶的乘用车尤为重要,可以通过电动混合系统的快速响应来克服蒸气系统的缓慢响应,从而提供了更多废热能回收的机会。发动机测试台架试验的结果表明,在发动机高负荷下,采用化学计量比运行时,制动比油耗降低了5%~7%,与模拟结果一致。这表明组合动力总成系统在城市、城郊和高速工况方面均具有优势。

关键词：有机朗肯循环废热回收轻度混合动力能量转换涡轮增压轿车柴油机