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Experimental Study on the Mobility of Channelized granular Mass Flow

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Acta geologica Sinica(English Edition) 2016年第3期90卷 988-998页

作者： ZHOU gongdan nigel g.WRIgHT SUN Qicheng CAI Qipeng Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences & Ministry of Water Conservancy School of Civil Engineering University of Leeds State Key Laboratory for Hydroscience and Engineering Tsinghua University College of Civil Engineering Huaqiao University

granular mass flows （e.g., debris flows/avalanches） in landslide-prone areas are of great concern because they often cause catastrophic disasters as a result of their long run-out distances and large impact forces. To investigate the factors influencing granular mass flow mobility, experimental tests were conducted in a flume model. granular materials consisting of homogeneous sand and non- homogeneous sandy soil were used for studying particle size effects. Run-out tests with variable flow masses, water contents, and sloping channel confinement parameters were conducted as well. The results indicated that granular mass flow mobility was significantly influenced by the initial water content; a critical water content corresponding to the smallest flow mobility exists for different granular materials. An increase in the total flow mass generally induced a reduction in the travel angle （an increase in flow mobility）. Consistent with field observations, the travel angles for different granular materials decreased roughly in proportion to the logarithm of mass. The flume model tests illustrate that the measured travel angles increase as the proportion of fine particles increases. Interestingly, natural terrain possesses critical confinement characteristics for different granular mass flows.

关键词： granular mass flow mobility water content flow mass fine particle channel confinement

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On the mechanical behavior of the human biliary system

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World Journal of gastroenterology 2007年第9期13卷 1384-1392页

作者： Xiaoyu Luo Wenguang Li nigel Bird Swee Boon Chin NA Hill Alan g Johnson Department of Mathematics University of Glasgow Glasgow G12 8QW United Kingdom Department of Mechanical Enginwring University of Sheffield Sheffield S1 3JD United Kingdom Academic Surgical Unit Royal Hallamshirc Hospital Sheffield S10 2JF United Kingdom

This paper reviews the progress made in understanding the mechanical behaviour of the biliary system. gallstones and diseases of the biliary tract affect more than 10% of the adult population. The complications of gallstones, i.e. acute pancreatitis and obstructive jandice, can be lethal, and patients with acalculous gallbladder pain often pose diagnostic difficulties and undergo repeated ultrasound scans and oral cholecystograms. Moreover, surgery to remove the gallbladder in these patients, in an attempt to relieve the symptoms, gives variable results. Extensive research has been carried out to understand the physiological and pathological functions of the biliary system, but the mechanism of the pathogenesis of gallstones and pain production still remain poorly understood. It is believed that the mechanical factors play an essential role in the mechanisms of the gallstone formation and biliary diseases. However, despite the extensive literature in clinical studies, only limited work has been carried out to study the biliary system from the mechanical point of view. In this paper, we discuss the state of art knowledge of the fluid dynamics of bile flow in the biliary tract, the solid mechanics of the gallbladder and bile ducts, recent mathematical and numerical modelling of the system, and finally the future challenges in the area.

关键词： Fluid dynamics gallstone Bile flow Cystic duct gallbladder Soft tissue mechanics Acalculousbiliary pain Stress Mechanical factors

Vegetation composition of old extensive green roofs(from 1980s germany)

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Ecological Processes 2014年第1期3卷 225-235页

作者： Christine E Thuring nigel Dunnett Department of Landscape Floor 9The Arts TowerWestern BankSheffieldSouth Yorkshire S102TNUK

Introduction:Since their development in the late 1970s in germany,extensive green roofs(EgR)have become increasingly popular as mitigation tools for urban environmental issues around the *** are planted with select species,which ensure consistent cover and performance over *** research presented herein is part of a systematic re-evaluation of EgR technology since the german industry ***:given the opportunity to access a small sample of old EgRs installed over 20 years ago in south-west germany,this research surveyed the vegetation and substrate with an interest in describing these parameters with time-through-space ***:Similar to previous studies,this preliminary work found correlations between roof age with vegetation(cover abundance and species diversity)and substrate properties(e.g.,depth,organic content,pH,and nutrients).Roof age had positive relationship with soil organic content(Corg),and negative relationships with substrate depth and soil *** soil variables are inter-related,as shallow acidic substrates create unfavourable conditions for decomposition and thereby the accumulation of *** variables correlated with EgR vegetation,suggesting a trend of simplified species composition over ***,Corg had a negative relationship with cover and species diversity of most life forms;only Sedum species had positive associations with ***:Considering the dynamics associated with shallow mineral substrates,and the greater floristic diversity of younger roofs,simple Sedum-based vegetation may represent a steady state for conventional EgRs.

关键词： Biodiversity Extensive green roofs germany Long-term performance Plant life forms Sedum Species diversity Substrate depth

Sediment balances in the Blue Nile River Basin

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International Journal of Sediment Research 2014年第3期29卷 316-328页

作者： Yasir S.A.ALI Alessandra CROSATO Yasir A.MOHAMED Seifeldin H.ABDALLA nigel g.WRIgHT UNESCO-IHE Westvest 72601 DA Delftthe Netherlands and Hydraulics Research CenterMinistry of Water Resources and ElectricityP.O.Box 318Wad MedaniSudan UNESCO-IHE Westvest 72601 DA Delft and Profat Hydraulics Research CenterMinistry of Water Resources and Electricity School of Civil Engineering University of LeedsFaculty of EngineeringLeeds LS2 9JT.United Kingdom Water Resources Technical Organ Ministry of Water Resources and ElectricityKhartoumSudan UNESCO-IHE Westvest 72601 DA Delft and Research Associate at Civil Engineering and Geosciences Delft University of TechnologyStevin weg 12628 CN Delftthe Netherlands

Rapid population growth in the upper Blue Nile basin has led to fast land-use changes from natural forest to agricultural *** resulted in speeding up the soil erosion process in the highlands and increasing sedimentation further downstream in reservoirs and irrigation *** present,several dams are planned across the Blue Nile River in Ethiopia and the grand Ethiopian Renaissance Dam is currently under construction near the border with *** will be the largest hydroelectric power plant in *** objective of this paper is to quantify the river flows and sediment loads along the Blue Nile River *** Soil and Water Assessment Tool was used to estimate the water flows from un-gauged *** assess model performance,the estimated sediment loads were compared to the measured ones at selected *** the gauged sub-basins,water flows and sediment loads were derived from the available flow and sediment *** fill in knowledge gaps,this study included a field survey in which new data on suspended solids and flow discharge were collected along the Blue Nile and on a number of *** comparison between the results of this study and previous estimates of the sediment load of the Blue Nile River at El Deim,near the Ethiopian Sudanese border,show that the sediment budgets have the right order of magnitude,although some uncertainties *** gives confidence in the results of this study providing the first sediment balance of the entire Blue Nile catchment at the sub-basin scale.

关键词： Blue Nile basin Sediment balance Field data Rating curve SWAT model

A simpliied fatigue assessment method for transverse illet welded joints

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Acta Mechanica Solida Sinica 2017年第2期30卷 198-208页

作者： Wei Shen Renjun Yan nigel Barltrop Kai Qin Feng He Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of EducationWuhan 430063 China State Key Laboratory of Ocean Engineering Shanghai University Tong University Shanghai 200240 China Department of Naval Architecture and Marine Engineering University of Strathclyde Glasgow G4OLZ UnitedKingdom

Under the as-welded condition the fatigue crack initiation period was considered nonexistent and Linear Elastic Fracture Mechanics（LEFM） was used to calculate fatigue strength for a range of weld geometries. Fracture mechanics assessment of welded joints requires accurate solutions for stress intensity factor（SIF）. However, the solutions for the SIF of complex welded joints are dificult to determine due to the complicated correction factors. Three methods for SIF prediction are discussed on illet welded specimens containing continuous or semi-elliptical surface cracks, including the traditional correction method Mk, the approximate correction method Kt, and the suggested additional crack size method（ac＋ae）.The new additional crack parameter ae is used to replace the stress concentration effect of weld proile Mk, which simpliies the calculation process. Experimental results are collected to support fatigue strength assessment of the additional crack size method.

关键词： Fillet welded joints Stress intensity factor(SIF) Additional crack size(ae) Fatigue strength

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genetic Diversity and Population Structure Analysis of Barley Landraces from Shanghai Region Using genotyping-by-Sequencing

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Phyton-International Journal of Experimental Botany 2023年第4期92卷 1275-1287页

作者： Luli Li nigel g.Halford Huihui Wang Yingjie Zong Zhenzhu guo Ruiju Lu Chenghong Liu Zhiwei Chen Shanghai Key Laboratory of Agricultural genetics and Breeding Biotechnology Research InstituteShanghai Academy of Agricultural SciencesShanghai201106China College of Fisheries and Life Science Shanghai Ocean UniversityShanghai201306China Rothamsted Research HarpendenAL52JQUK Qingdao OE Biotechnology Company Limited Qingdao266100China

Barley(Hordeum vulgare L.)is an important economic crop for food,feed and industrial raw *** the present research,112 barley landraces from the Shanghai region were genotyped using genotyping-by-sequencing(gBS),and the genetic diversity and population structure were *** results showed that 210,268 Single Nucleotide Polymorphisms(SNPs)were present in total,and the average poly-morphism information content(PIC)was *** diversity and population structure analyses suggested that these barley landraces were differentiated and could be divided into three sub-groups,with morphological traits of row-type and adherence of the hulls the main distinguishing factors between *** with similar or duplicated names were also investigated according to their genetic backgrounds and seed *** study provided valuable information on barley landraces from the Shanghai region,and showed that all these barley landraces should be protected and used for future breeding programs.

关键词： Hordeum vulgare L cluster analysis population structure SNP markers

Drug therapy for heart failure in older patients —what do they want？

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Journal of geriatric Cardiology 2015年第2期12卷 165-173页

作者： Donah Zachariah Jacqueline Taylor nigel Rowell Clare Spooner Paul R Kalra Portsmouth Hospitals NHS Trust Portsmouth P06 3L Y UK glasgow Royal Infirmary Glasgow G40SF UK South Tees Hospitals NHS Foundation Trust TS4 3BW UK Servier Laboratories Ltd SL3 6P J UK

Chronic heart failure （CHF） is predominantly seen in older patients, and therefore real life medicine often requires the extrapolation of findings from trials conducted in much younger populations. Prescribing patterns and potential benefits in the elderly are heavily influenced by polypharmacy and co-morbid pathologies. Increasing longevity may become less relevant in the frail elderly, whereas improving quality of life （QoL） often becomes priority; the onus being on improving wellbeing, maintaining independence for longer, and delaying institution- alisation. Specific studies evaluating elderly patients with CHF are lacking and little is known regarding the tolerability and side-effect profile of evidence based drug therapies in this population. There has been recent interest on the impact of heart rate in patients with symptomatic CHF. Ivabradine, with selective heart rate lowering capabilities, is of benefit in patients with CHF and left ventricular systolic dysfunction in sinus rhythm, resulting in reduction of heart failure hospitalisation and cardiovascular death. This manuscript will focus on CHF and the older patient and will discuss the impact of heart rate, drug therapies and tolerability. It will also highlight the tmmet need for specific studies that focus on patient-centred study end points rather than mortality targets that characterise most therapeutic trials. An on-going study evalu- ating the impact of ivabradine on QoL that presents a unique opportunity to evaluate the tolerability and impact of an established therapy on a wide range of real life, older patients with CHF will be discussed.

关键词： Heart failure Heart rate Quality of life The elderly

Observation or resection of pancreatic intraductal papillary mucinous neoplasm:An ongoing tug of war

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World Journal of gastrointestinal Oncology 2019年第12期11卷 1092-1100页

作者： Jan Rune Aunan nigel B.Jamieson Kjetil Sφreide Department of gastrointestinal Surgery HPB UnitStavanger University HospitalStavanger 4068Norway Wolfson Wohl Cancer Research Centre Institute of Cancer SciencesUniversity of GlasgowGlasgow G611BDUnited Kingdom West of Scotland Pancreatic Unit Glasgow Royal InfirmaryGlasgow G40SFUnited Kingdom gastrointestinal Translational Research Unit Laboratory for Molecular MedicineStavanger University HospitalStavanger 4068Norway Department of Clinical Medicine University of BergenBergen 5003Norway

An increasing number of patients are being referred to pancreatic centres around the world due to often incidentally discovered cystic neoplasms of the *** evaluation and management of pancreatic cystic neoplasms is a controversial topic and with existing guidelines based on a lack of strong evidence there is discordance between centres and guidelines with regard to when to offer surgery and when to favour *** frequency,duration and modality of surveillance is also controversial as this is resource-consuming and must be balanced against the perceived benefits and risks *** there is consensus that the risk of malignancy should be balanced against the lifeexpectancy and comorbidities,the indications for surgery and surveillance strategies vary among the ***,the tug of war between surveillance or resection *** we discuss the recommendations from guidelines with further accumulating data and emerging reports on intraductal papillary mucinous neoplasm in the literature.

关键词： Neoplasia Pancreatic cancer Pancreatic cyst Diagnosis Resection Surveillance Mutation Biomarker

Targeting inflammation in pancreatic cancer: Clinical translation

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World Journal of gastrointestinal Oncology 2016年第4期8卷 380-388页

作者： Colin William Steele Nina Angharad Kaur gill nigel Balfour Jamieson Christopher ross Carter Department of Pancreaticobiliary Surgery Glasgow Royal Infirmary Department of general Surgery South Glasgow University Hospital

Preclinical modelling studies are beginning to aid development of therapies targeted against key regulators of pancreatic cancer progression. Pancreatic cancer is an aggressive, stromally-rich tumor, from which few people survive. Within the tumor microenvironment cellular and extracellular components exist, shielding tumor cells from immune cell clearance, and chemotherapy, enhancing progression of the disease. The cellular component of this microenvironment consists mainly of stellate cells and inflammatory cells. New findings suggest that manipulation of the cellular component of the tumor microenvironment is possible to promote immune cell killing of tumor cells. Here we explore possible immunogenic therapeutic strategies. Additionally extracellular stromal elements play a key role in protecting tumor cells from chemotherapies targeted at the pancreas. We describe the experimental findings and the pitfalls associated with translation of stromally targeted therapies to clinical trial. Finally, we discuss the key inflammatory signal transducers activated subsequent to driver mutations in oncogenic Kras in pancreatic cancer. We present the preclinical findings that have led to successful early trials of STAT3 inhibitors in pancreatic adenocarcinoma.

关键词： Pancreatic cancer Inflammation Stroma Microenvironment