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Global assessment of nitrogen fertilizer:The SCOPE/IGBP Nitrogen Fertilizer rapid Assessment Project

Science China(Life Sciences) 2005年第z2期48卷 759-766页

作者： Arvin r.Mosier J.Keith Syers john r.Freney Agricultural and Biological Engineering Department University of Florida GainesvilleFL 32611USA mae Fah Luang University Chaiang rai Thailand CSIrO Plant Industry ACT 2601 Australia

Nitrogen (N) availability is a key role in food and fiber production. Providing plant-available N through synthetic fertilizer in the 20th and early 21st century has been a major contributor to the increased production required to feed and clothe the growing human *** continue to meet the global demands and to minimize environmental problems, significant improvements are needed in the efficiency with which fertilizer N is utilized within production systems. There are still major uncertainties regarding the fate of fertilizer N added to agricultural soils and the potential for reducing losses to the environment. Enhancing the technical and economic efficiency of fertilizer N is seen to promote a favorable situation for both agricultural production and the environment, and this has provided much of the impetus for a new N fertilizer *** address this important issue, a rapid assessment project on N fertilizer (NFrAP) was conducted by SCOPE (the Scientific Committee on Problems of the Environment) during late 2003 and early 2004. This was the first formal project of the International Nitrogen Initiative (INI). As part of this assessment, a successful international workshop was held in Kampala, Uganda on 12 -16 January, 2004. This workshop brought together scientists from around the world to assess the fate of synthetic fertilizer N in the context of overall N inputs to agricultural systems, with a view to enhancing the efficiency of N use and reducing negative impacts on the *** of the assessment highlighted the problems of too little N for crop production to meet the nutrient requirements of sub-Saharan Africa and the oversupply of N in the major rice-growing areas of China. The results of the assessment are presented in a book (SCOPE 65)which is now available to provide a basis for further discussions on N fertilizer.

关键词： crop production, environmental quality, nitrate leaching, soil fertility.

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Simplified full-depth precast concrete deck panel systems for accelerated bridge construction

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Journal of Modern Transportation 2016年第4期24卷 251-260页

作者： Zhongguo john ma Yulin Zhan Lin Xiao Lungui Li Weiwei Lu Department of Civil and Environmental Engineering University of Tennessee School of Civil Engineering Southwest Jiaotong University Key Laboratory of High-Speed railway Engineering Ministry of Education Southwest Jiaotong University

A simplified full-depth precast concrete deck panel system for accelerating bridge construction （ABC） is introduced and a finite dement analysis （FEA） is con- ducted to investigate the static and dynamic responses of this conceptual deck system. The FEA results are compared to those of the traditional full-depth precast concrete deck panel system. The comparison results show that the mechanical behavior of the new deck system is different from that of the traditional deck system. The concrete decks in the new system act as two-way slabs, instead of the one-way slab in the traditional system. Meanwhile, the connections in both the longitudinal and transverse direc- tions may need to accommodate the negative moments. Compared to those in the traditional system, the longitu- dinal nominal stress at middle span increases a lot in the new deck system and the effective flange width varies significantly. In addition, the dynamic results show that the impact factor is influenced by the spacing of connections. Finally, some design concerns of the new deck system are proposed.

关键词： Simplified full-depth precast concrete deckpanel systems ~ Accelerated bridge construction ~ Structuralresponse

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Historic distribution and driving factors of human-caused fires in the Chinese boreal forest between 1972 and 2005

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Journal of Plant Ecology 2015年第5期8卷 480-490页

作者： Futao Guo john L.Innes Guangyu Wang Xiangqing ma Long Sun Haiqing Hu Zhangwen Su Faculty of Forestry Fujian Agriculture and Forestry UniversityNo.15 Shangxiadian RoadFuzhou 350002China Sustainable Forest management Laboratory Faculty of ForestryUniversity of British Columbia2424 Main MallVancouverBritish Columbia V6T 1Z4Canada Faculty of Forestry Northeast Forestry UniversityNo.26 Hexing RoadHarbinHeilongjiang Province 150040China

Aims The pattern and driving factors of forest fires are of interest for fire occurrence prediction and forest fire *** aims of the study were:(i)to describe the history of human-caused fires by season and size of burned area over time;(ii)to identify the spatial patterns of human-caused fires and test for the existence of‘hotspots’to determine their exact locations in the Daxing’an mountains;(iii)to determine the driving factors that determine the spatial distribution and the possibility of human-caused fire *** In this study,K-function and Kernel density estimation were used to analyze the spatial pattern of human-caused *** analysis was conducted in s-plus and arcgIs environments,*** analysis of driving factors was performed in SPSS 19.0 based on a logistic regression *** variables used to identify factors that influence fire occurrence included vegetation types,meteorological conditions,socioeconomic factors,topography and infrastructure factors,which were extracted and collected through the spatial analysis mode of arcgIs and from official statistics,*** Findings The annual number of human-caused fires and the area burnt have declined since 1987 due to the implementation of a forest fire protection *** were significant spatial heterogeneity and seasonal variations in the distribution of human-caused fires in the Daxing’an *** heterogeneity was caused by elevation,distance to the nearest railway,forest type and temperature.a logistic regression model was developed to predict the likelihood of human-caused fire occurrence in the Daxing’an mountains;its global accuracy attained 64.8%.The model was thus comparable to other relevant studies.

关键词： anthropogenic fire spatial distribution K-function Kernel intensity estimation boreal forest logistic regression

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Advantages of using the CrISPr/Cas9 system of genome editing to investigate male reproductive mechanisms using mouse models

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Asian Journal of Andrology 2015年第4期17卷 623-627页

作者： Samantha AM Young r john Aitken masahito Ikawa Priority research Centre in reproductive Science Discipline of Biological Sciences Faculty of Scienceand IT University of Newcastle Callaghan NSWAustralia Animal resource Centre for InfectiousDiseases Research Institute for Microbial DiseasesOsaka University Suita Osaka Japan.Correspondence: Prof. M Ikawa

Gene disruption technology has long been beneficial for the study of male reproductive biology. However, because of the time and cost involved, this technology was not a viable method except in specialist laboratories. The advent of the CrISPr/Cas9 system ofgene disruption has ushered in a new era of genetic investigation. Now, it is possible to generate gene-disrupted mouse models in very tittle time and at very little cost. 1his Highlight article discusses the application of this technology to study the genetics of male fertility and looks at some of the future uses of this system that could be used to reveal the essential and nonessential genetic components of male reproductive mechanisms.

关键词： Advantages investigate mechanisms

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The 12th International Symposium on Spermatology

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Asian Journal of Andrology 2015年第4期17卷 519-520页

作者： r john Aitken Jim M Cummins Brett Nixon Priority research Centre in reproductive Science Discipline of Biological Sciences and HunterMedical Research Institute University of NewcastleNSW 2308 Australia Division of Veterinary andBiomedical Sciences Murdoch University MurdochWA. Australia.

The 12th International Symposium of Spermatology continued the excellent tradition of this meeting since its inception in 1969 when the first Symposium was held in Italy under the Chairmanship of Professor Baccio Baccetti. This unique Symposium is held every 4 years and serves as a beacon for sperm cell biologists from all over the world, regardless of which species, animal or plant, they are working on. This willingness to embrace the fundamental biology of this distinctive cell type without species limitations is one of the hallmarks of this Symposium. For sperm biologists - it is our Olympics. The meeting in Newcastle, NSW brought together around 300 biologists from more than 22 different countries covering North and South America, Africa, Europe, Asia and Australia. Given the considerable distances and high cost involved in travelling to the East Coast of NSW, this was an outstanding outcome. The Symposium featured a series of 31 plenary lectures culminating in the prestigious Thaddeus mann Memorial Lecture, which was delivered with typical grace and brilliance by Professor masaru Okabe.

关键词： International Symposium Spermatology

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Food,fibre,bile acids and the pelvic floor: An integrated low risk low cost approach to managing irritable bowel syndrome

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World Journal of Gastroenterology 2015年第40期21卷 11379-11386页

作者： Hamish Philpott Sanjay Nandurkar john Lubel Peter r Gibson Monash University Eastern HealthThe Alfred Hospital

Patients presenting with abdominal pain and diarrhea are often labelled as suffering from irritable bowel syndrome,and medications may be used often without success. Advances in the understanding of the causes of the symptoms(including pelvic floor weakness and incontinence,bile salt malabsorption and food intolerance) mean that effective,safe and well tolerated treatments are now available.

关键词： Bile acids Pelvic floor Food intolerance Irritable

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Genetic variability of the stable fly assessed on a global scale using amplified fragment length polymorphism

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Insect Science 2016年第5期23卷 695-703页

作者： Kathleen M Kneeland Steven r. Skoda john E. Foster Department of Entomology 103 Entomology Haft University of Nebraska-Lincoln Lincoln NE 68583 USDA-ArS-KBUSLIrL Screwworm research Unit 2700 Fredericksburg Road Kern/ille TX 78028 USA

The stable fly, Stomoxys calcitrans （L.）（Diptera： Muscidae）, is a blood-feeding, economically important pest of animals and humans worldwide. Improved management strategies are essential and their development would benefit from studies on genetic di- versity of stable flies. Especially if done on a global scale, such research could generate information necessary for the development and application of more efficient control meth- ods. Herein we report on a genetic study of stable flies using amplified fragment length polymorphism, with samples of 10-40 individuals acquired from a total of 25 locations in the Nearctic, Neotropic, Palearctic, Afrotropic and Australasian biogeographical regions. We hypothesized that genetic differentiation would exist across geographical barriers. Although Fsx （0.33） was moderately high, the Gsx （0.05; representing genetic diversity between individuals） was very low; Nm values （representing gene flow） were high （9.36）. The mismatch distribution and tests of neutrality suggested population expansion, with no genetic differentiation between locations. The analysis of molecular variance （AMOVA） results showed the majority of genetic diversity was within groups. The mantel test showed no correlation between geographic and genetic distance; this strongly supports the AMOVA results. These results suggest that stable flies did not show genetic differentiation but are panmictic, with no evidence of isolation by distance or across geographical barriers.

关键词： AFLP biting flies external parasites genetic diversity livestock pests Stomoxys calcitrans

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Immune checkpoint inhibitor-mediated colitis in gastrointestinal malignancies and inflammatory bowel disease

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World Journal of Gastrointestinal Oncology 2021年第8期13卷 772-798页

作者： Alexa r Weingarden Samuel J S rubin john Gubatan Division of Gastroenterology and Hepatology Department of MedicineStanford UniversityRedwood CityCA 94063United States Stanford University School of Medicine Stanford UniversityRedwood CityCA 94063United States

Immune checkpoint inhibitors(ICI)have markedly changed the landscape of cancer *** re-invigorating the immune system against tumors,ICI provide novel therapeutic options for a broad variety of malignancies,including many gastrointestinal(GI)***,these therapies can also induce autoimmune-like side effects in healthy tissue across the *** of the most common of these side effects is ICI-mediated colitis and diarrhea(IMC).Here,we review the incidence and risk of IMC in ICI therapy,with a focus on what is known regarding IMC in patients with GI *** also discuss data available on the use of ICI and risk of IMC in patients with pre-existing inflammatory bowel disease,as these patients may have increased risk of IMC due to their underlying intestinal pathology.

关键词： Immune checkpoint inhibitors Cytotoxic T-lymphocyte antigen 4 Programmed cell death protein-1 Inflammatory bowel disease Gastrointestinal cancer

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Persistence and growth of faecal culturable bacterial indicators in water column and sediments of Vidy Bay,Lake Geneva,Switzerland

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Journal of Environmental Sciences 2009年第1期21卷 62-69页

作者： POTE john HALler Laurence KOTTELAT régis SASTrE Vincent ArPAGAUS Philippe WILDI Walter University of Geneva F.-A. Forel Institute10 route de Suisse1290 VersoixSwitzerland

The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators （CBI） including total coliforms （TC） and faecal coliforms represented by Escherichia coli, enterococcus （ENT）, and aerobic mesophilic bacteria （AMB） in the surface sediments and the water column of Vidy Bay fLake Geneva, City of Lausanne, Switzerland）. The study was carded out for 60 d using microcosms containing Sewage Treatment Plant （STP） effluent and nonsterile water without CBI, as well as contaminated and non-contaminated sediments. The effects of water temperature and of organic matter associated with sediments on the survival of CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and in the STP effluent was almost identical in the order of 10^5-10^7, 10^4-10^6, 10^5-10^5, and 10^4-10^7 CFU/100 g sediment or/100 mL water for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was low and in the water column at a temperature of 10℃ after 5 d of experimentation. In addition, a growth of CBI was observed in the sediment which is rich in organic matter at 20℃. The results of this study indicate：（1） the higher concentrations of the CBI observed in different points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources of the Bay contamination including STP and the Chamberonne and Flon rivers, but also by the persistence, removal from sediment and multiplication of CBI in the sediment and water column; （2） the sediment of Vidy Bay constitute a reservoir of CBI and can even support their growth; and （3） the CBI not only survive in sediments, but also can be remobilized and increased in the water column, therefore, it become a permanent microbiological pollution in Vidy Bay.

关键词： Lake Geneva faecal pollution persistence multiplication human health risk

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The evolution of surgical and medical treatment of aortic root aneurysm

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Frontiers of Medicine 2014年第4期8卷 427-432页

作者： Xu Yu Jin Li Yuan mario Petrou john r. Pepper Oxford Heart Centre John Radcliffe Hospital Oxford OX3 9DU UK Oxford Echo Core Lab NDCLS Radcliffe Department of Medicine University of Oxford Oxford OX3 9DU UK Academic Department of Cardiac Surgery Royal Brompton Hospital London SW3 6NP UK Department of Ultrasonography Union Hospital Tongji Medical College Huazhong University of Science and Teehnology Wuhan 430022 China

Since first report of aortic root replacement in 1968, the surgical risk and long term outcome of patients with aortic root aneurysm have been continuously improving. In the last 30 years, the surgical approach is also evolving towards more valve conservation with prophylactical intervention at an earlier clinical stage. Translational research has also led to emerging surgical innovation and new drug therapy. Their efficacies are currently under vigorous clinical trials and evaluations.

关键词： aortic root aneurysm aortic root replacement valve sparing root replacement personalised external aortic rootsupport

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