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Impact of thermal processes on multi-crystalline silicon

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Frontiers in Energy 2017年第1期11卷 32-41页

作者： Moonyong KIM Phillip HAMER Hongzhao LI David PAYNE Stuart WENHAM malcolm ABBOTT Brett HALLAM School of Photovoltaic and Renewable Energy Engineering Universityof New South Wales Sydney NSW 2052 Australia Department of Materials University of Oxford Oxford OX1 3PH United Kingdom

Fabrication of modem multi-crystalline silicon solar cells involves multiple processes that are thermally intensive. These include emitter diffusion, thermal oxida- tion and firing of the metal contacts. This paper illustrates the variation and potential effects upon recombination in the wafers due to these thermal processes. The use of light emitter diffusions more compatible with selective emitter designs had a more detrimental effect on the bulk lifetime of the silicon than that of heavier diffusions compatible with a homogenous emitter design and screen-printed contacts. This was primarily due to a reduced effectiveness of gettering for the light emitter. This reduction in lifetime could be mitigated through the use of a dedicated gettering process applied before emitter diffusion. Thermal oxida- tions could greatly improve surface passivation in the intra- grain regions, with the higher temperatures yielding the highest quality surface passivation. However, the higher temperatures also led to an increase in bulk recombination either due to a reduced effectiveness of gettering, or due to the presence of a thicker oxide layer, which may interrupt hydrogen passivation. The effects of fast firing were separated into thermal effects and hydrogenation effects. While hydrogen can passivate defects hence improving the performance, thermal effects during fast firing can dissolve precipitating impurities such as iron or de-getter impurities hence lower the performance, leading to a poisoning of the intra-grain regions.

关键词： gettering grain boundaries hydrogen impurities oxidation passivation solar cell

The Sulfate Transporter Family in Wheat： Tissue-Specific Gene Expression in Relation to Nutrition

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Molecular Plant 2010年第2期3卷 374-389页

作者： Peter Buchner Saroj Parmar Anne Kriegel Magali Carpentier malcolm J. Hawkesford Rothamsted Research Plant Science Department West Common Harpenden Hertfordshire AL5 2JQ UK Molecular Plant Nutrition University of Hohenheim Stuttgart Germany

Sulfate uptake and distribution in plants are managed by the differential expression of a family of transporters, developmentally, spatially, and in response to sulfur nutrition. Elucidation of the signaling pathways involved requires a knowledge of the component parts and their interactions. Here, the expression patterns of the full complement of sulfate transporters in wheat, as influenced by development and sulfur nutrition, are described. The 10 wheat sulfate transporters characterized here are compared to the gene families for both rice and Brachypodium, for whom full genome information is available. Expression is reported in young seedlings with a focus on roles in uptake from nutrient solution and differential expression in relation to sulfate deprivation. In addition, patterns of expression in all organs at the grain filling stage are reported and indicate differential responses to nutritional signals of the individual transporters in specific tissues and an overall coordination of uptake, storage, and remobilization to deliver sulfur to the developing grain.

关键词： Sulfate transporter wheat transcriptional regulation sulfur nutrition grain filling.

Cellular and molecular aspects of gastric cancer

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World Journal of Gastroenterology 2006年第19期12卷 2979-2990页

作者： malcolm G Smith Georgina L Hold Eiichi Tahara Emad M El-Omar Department of Medicine and Therapeutics Aberdeen University ForesterhillAberdeen AB25 2ZDScotlandUnited Kingdom

Gastric cancer remains a global killer with a shifting burden from the developed to the developing world. The cancer develops along a multistage process that is defined by distinct histological and pathophysiological phases. Several genetic and epigenetic alterations mediate the transition from one stage to another and these include mutations in oncogenes, tumour suppressor genes and cell cycle and mismatch repair genes. The most significant advance in the fight against gastric caner came with the recognition of the role of Helicobacter pylori （H pylori） as the most important acquired aetiological agent for this cancer. Recent work has focussed on elucidating the complex host/microbial interactions that underlie the neoplastic process. There is now considerable insight into the pathogenesis of this cancer and the prospect of preventing and eradicating the disease has become a reality. Perhaps more importantly, the study of H pylori-induced gastric carcinogenesis offers a paradigm for understanding more complex human cancers. In this review, we examine the molecular and cellular events that underlie Hpyloriinduced gastric cancer.

关键词： Gastric cancer Helicobacter pylori Hostmicrobial interactions Inflammation Molecular mechanisms Host genetics

Effect of Horizontal Resolution on the Representation of the Global Monsoon Annual Cycle in AGCMs

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Advances in Atmospheric Sciences 2018年第8期35卷 107-124页

作者： Lixia ZHANG Tianjun ZHOU Nicholas P.KLINGAMAN Peili WU malcolm ROBERTS LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China National Centre for Atmospheric Science and Department of Meteorology University of ReadingReading RG6 6BBUnited Kingdom Met Office Hadley Centre ExeterEX1 3PBUnited Kingdom

The sensitivity of the representation of the global monsoon annual cycle to horizontal resolution is compared in three AGCMs： the Met Office Unified Model-Global Atmosphere 3.0; the Meteorological Research Institute AGCM3; and the Global High Resolution AGCM from the Geophysical Fluid Dynamics Laboratory. For each model, we use two horizon- tal resolution configurations for the period 1998-2008. Increasing resolution consistently improves simulated precipitation and low-level circulation of the annual mean and the first two annual cycle modes, as measured by the pattern correla- tion coefficient and equitable threat score. Improvements in simulating the summer monsoon onset and withdrawal are region-dependent. No consistent response to resolution is found in simulating summer monsoon retreat. Regionally, in- creased resolution reduces the positive bias in simulated annual mean precipitation, the two annual-cycle modes over the West African monsoon and Northwestern Pacific monsoon. An overestimation of the solstitial mode and an underestimation of the equinoctial asymmetric mode of the East Asian monsoon axe reduced in all high-resolution configurations. Systematic errors exist in lower-resolution models for simulating the onset and withdrawal of the summer monsoon. Higher resolution models consistently improve the early summer monsoon onset over East Asia and West Africa, but substantial differences exist in the responses over the Indian monsoon region, where biases differ across the three low-resolution AGCMs. This study demonstrates the importance of a multi-model comparison when examining the added value of resolution and the importance of model physical parameterizations for simulation of the Indian monsoon.

关键词： global monsoon high resolution modeling monsoon annual cycle AMIP

CA19-9 antigen levels can distinguish between benign and malignant pancreaticobiliary disease

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 620-626页

作者： Gareth Morris-Stiff Mary Teli Nicky Jardine malcolm CA Puntis Department of Surgery University Hospital of Wales

BACKGROUND:CA19-9 is a carbohydrate tumor-associated antigen which is frequently upregulated in pancreatobiliary ***,it may also be elevated in patients with jaundice in the absence of a tumor due to biliary obstruction,and in other non-hepato-pancreatico-biliary *** study aimed to evaluate whether CA19-9 levels could accurately differentiate between benign and malignant pancreatobiliary ***:All patients referred to a single surgeon for investigation of pancreaticobiliary disease in 2003 in whom a firm diagnosis had been established were *** malignant disease,a histological diagnosis was required but for benign disease a firm radiological diagnosis was deemed *** patients were divided into 4 categories:pancreatic adenocarcinoma(PCa);cholangiocarcinoma(CCa);chronic pancreatitis(CP)and biliary calculous disease(Calc).Bilirubin and alkaline phosphatase levels corresponding to the point of assessment of CA19-9 were also ***:Final diagnoses were made of pancreatic adenocarcinoma(PCa,n=73),cholangiocarcinoma(CCa,n=19),ampullary carcinoma(Amp,n=7),neuroendocrine carcinoma(Neu,n=4),duodenal carcinoma(Duo,n=3),chronic pancreatitis(CP,n=115),and biliary calculous disease(Calc,n=27).Median CA19-9 levels(U/ml)were:PCa,653;CCa,408;Duo,403;Calc,27;CP,19;Neu,10.5;Amp,8(reference range:0-37).The CA19-9 levels were significantly greater for malignant than for benign disease,could differentiate PCa from CCa/Duo,and were significantly higher in unresectable than in resectable *** sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)for CA19-9 were 84.9%,69.7%,67.7%and 86.1%,respectively.A ROC analysis provided an area under the curve for CA19-9 of 0.871(0.820-0.922),giving an optimal CA19-9 of 70.5 U/ml for differentiating benign from malignant *** this cut-off,the sensitivity was 82.1%,while specificity,PPV and NPV improved to 85.9%,81.3%and 86.5%,*** sta

关键词： CA19-9 antigen pancreatic disease biliary tract disease malignant benign

Mechanization technology:The key to sugarcane production in China

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International Journal of Agricultural and Biological Engineering 2013年第1期6卷 1-27页

作者： Ou Yinggang malcolm Wegener Yang Dantong Liu Qingting Zheng Dingke Wang Meimei Liu Haochun College of Engineering South China Agricultural UniversityGuangzhou 510642China School of Agriculture and Food Sciences The University of QueenslandBrisbaneQLD4072Australia

Sugarcane is an important cash crop in southern China now planted on about 1.5 million ha in the main production areas in Guangxi,Zhuang Autonomous Region and Yunnan,Guangdong,and Hainan *** the cost of labor in China is increasing rapidly and the price of local sugar is uncompetitive with the product from mechanized international producers,China needs to change its sugarcane production methods from manual work to mechanization in order to catch up with international trends in this global *** a lot of effort in China have gone into sugarcane mechanization since the 1960s,the overall level of mechanization in sugarcane production is still only approximately 30%,which is about 20%lower than that achieved in the other main field *** all of the sugarcane grown in China is still harvested by *** order to summarize past experience and promote the mechanization of sugarcane production in China,this paper reviews the whole process of developing mechanization since 1960s and describes the current state of sugarcane mechanization in *** research currently being undertaken and the main obstacles to be overcome in developing a mechanized sugarcane production system,are *** design and testing of sugarcane harvesting machinery and its key components has been a significant research area by some Chinese universities,research institutes,and manufacturing companies in these past *** paper reviews that research and outlines the main achievements which have been made in this *** harvesting systems for sugarcane,and the appropriate harvesting patterns suitable for different growing conditions applying in China,have also been *** paper concludes with some comments on the future directions for progress in China’s mechanization of sugarcane production and some policy suggestions to facilitate the industry's transition.

关键词： mechanization technology sugarcane production sugarcane harvester sugarcane machinery development pattern

3D bioprinting for biomedical devices and tissue engineering: A review of recent trends and advances

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Bioactive Materials 2018年第2期3卷 144-156页

作者： Soroosh Derakhshanfar Rene Mbeleck Kaige Xu Xingying Zhang Wen Zhong malcolm Xing Department of Mechanical Engineering University of ManitobaWinnipegR3T 2N2Canada Department of Biosystems Engineering University of ManitobaWinnipegR3T 2N2Canada

3D printing,an additive manufacturing based technology for precise 3D construction,is currently widely employed to enhance applicability and function of cell laden *** on novel compatible biomaterials for bioprinting exhibiting fast crosslinking properties is an essential prerequisite toward advancing 3D printing applications in tissue *** to improve fabrication process and cell encapsulation are two of the main factors to be considered in development of 3D *** important factors include but are not limited to printing fidelity,stability,crosslinking time,biocompatibility,cell encapsulation and proliferation,shear-thinning properties,and mechanical properties such as mechanical strength and *** this review,we recite recent promising advances in bioink development as well as bioprinting ***,an effort has been made to include studies with diverse types of crosslinking methods such as photo,chemical and ultraviolet(UV).We also propose the challenges and future outlook of 3D bioprinting application in medical sciences and discuss the high performance bioinks.

关键词： Bioprinting Hydrogel Extrusion Inkjet Stereolithography Laser-assisted Review 3D printing

INVERSION OF THE BREMMER SERIES

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Journal of Computational Mathematics 2017年第5期35卷 586-599页

作者： Hala A.H. Shehadeh Alison E. malcolm John C. Schotland Department of Mathematics and Statistics James Madison University Harrisonburg VA 22801 Earth Sciences Department Memorial University of Newfoundland St John's Canada Department of Mathematics and Department of Physics University of Michigan Ann Arbor MI 48109 USA

We consider the inverse backscattering problem for scalar waves in one dimension. We analyze the convergence of the inverse Bremmer series in this context and study its use in numerical simulations.

关键词： Inverse scattering.

Strengthening biological security after COVID-19:Using cartoons for engaging life science stakeholders with the Biological and Toxin Weapons Convention(BTWC)

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Journal of Biosafety and Biosecurity 2022年第1期4卷 68-74页

作者： Tatyana Novossiolova Simon Whitby malcolm Dando Lijun Shang The Law Program of the Center for the Study of Democracy Bulgaria Division of Peace Studies University of Bradford BradfordUnited Kingdom School of Human Sciences London Metropolitan UniversityLondonUnited Kingdom Biological Security Research Centre London Metropolitan UniversityLondonUnited Kingdom

The devastating effects of the COVID-19 pandemic have acutely shown the need for maintaining robust international and national systems for biological security and ensuring that life sciences are used only for peaceful *** science stakeholders can play an important role in safeguarding scientific and technological advances in biology and related fields against accidental or deliberate misuse,not least because they are on the frontlines of driving *** this paper,we argue that enhancing awareness and understanding of the risk of deliberate disease is essential for effective biological *** first discuss the issue of‘dual use’in science and technology as it relates to disarmament and non-proliferation of weapons of mass ***,we review how scientist engagement with dual-use risks has been addressed in the context of the Biological and Toxin Weapons Convention(BTWC).Third,we report on the development of an innovative awarenessraising tool,a cartoon series,that can be used for engaging life science stakeholders with BTWC ***,we outline a set of practical considerations for promoting sustainable life science engagement with the BTWC.

关键词： Cartoon Life sciences Biological security Biological and Toxin Weapons Convention Awareness Engagement