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Chinese Journal of Chemistry 2021年第6期39卷 1659-1666页

作者： Zhiyuan Qian Yukun Cheng Shunan Zhao keith man-Chung Wong Department of Chemistry Southern University of Science and TechnologyNo.1088Tangchang BoulevardNanshan District，ShenzhenGuangdong 518055China

A new bipyridine fused rhodamine-like chelating ligand and the corresponding transition metal complexes of platinum(Ⅱ)and iridi-um(Ⅲ)have been designed,synthesized and structurally characterized by X-ray *** photophysical properties and acid-or metal ion-promoted spirocarbon ring-opening properties have been *** platinum(Ⅱ)and iridium(Ⅲ)complexes show a drastic color change in solution with Hg^(2+) ions and emergency of an absorption band at around 450-600 nm,assignable to the absorption band of the ring-opened rhodamine-like *** platinum(Ⅱ)complex was suggested to undergo dissociation with Hg^(2+) ion,based on the corresponding absorption titration *** titration studies of iridium(Ⅲ)complexes were found to suffer from the quenching process,probably due to the presence of a lower-lying non-emissive excited state from the ring-opened form of ligand.

关键词： Rhodamine Transition metals Sensor Luminescence Bipyridine

Forest composition and red oak (Quercus sp.) response to elevation gradients across greentree reservoirs

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Forest Ecosystems 2023年第5期10卷 607-617页

作者： Cassandra Hug Pradip Saud keith mcKnight Douglas C.Osborne College of Forestry Agriculturaland Natural ResourcesUniversity of Arkansas at MonticelloMonticelloAR71656USA USFWS/Lower mississippi Valley Joint Venture TylerTX75707USA Five Oaks Ag Research and Education Center HumphreyAR72073USA

Elevation gradients within forested wetlands have long been recognized for their role in defining species composition through factors such as hydrology and soil *** reservoirs(GTRs)are leveeimpounded tracts of bottomland hardwood forest flooded throughout the winter months to provide habitat for overwintering *** flooding of GTRs alters the forest composition due to flood frequency,depth,and duration in combination with slight changes in *** evaluate the effect of elevation gradients,soil properties,and management techniques in the overstory species composition and red oak(Quercus spp.)species abundance,we inventoried 662 plots across 12 independent GTRs in eastern *** the lower elevations ranging from 50.98 to 54.99 m above sea level,the importance value index(IVI)was highest for nuttall oak(Quercus texana)and overcup oak(Quercus lyrata),whereas IVI shifted to cherrybark oak(Quercus pagoda)in the higher elevations ranging from 54.99 to 58.00 *** diversity did not differ by elevation gradient,soil property,or management technique within *** diversity,using non-metric multi-dimensional scaling(NmDS)analysis,indicated site-specific variability significantly correlated with the environmental predictors,including elevation(R^(2)=0.57),easting(R^(2)=0.47),soil texture(R^(2)=0.21),and pH(R^(2)=0.12).Red oak species-specific mixed-effects modeling of abundance response using Poisson distribution suggested an inverse correlation of nuttall oak and a direct correlation of cherrybark oak abundance with ***,willow oak(Quercus phellos)abundance was not significantly affected by elevation but was by silt loam soil texture and restoration management *** findings will aid management efforts to reduce the dominance of less desirable species that are prominent under specific environmental conditions and promote the dominance of more desirable *** GTR sustainability is increas

关键词： Bottomland hardwoods Diversity Forested wetland Overstory Red oak Soil Thinning and management

QTL mapping and identification of SNP-haplotypes affecting yield components of Theobroma cacao L.

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Horticulture Research 2020年第1期7卷 2444-2461页

作者： Luciel dos Santos Fernandes Fábio m.Correa keith TIngram Alex-Alan Furtado de Almeida Stefan Royaert mars Center for Cocoa Science CP 55ItajuípeBA CEP 45.630-000Brazil Departamento de Ciências Biológicas Universidade Estadual de Santa CruzRodovia Ilhéus-ItabunaKm 16Bairro SalobrinhoIlhéusBA CEP 45.662-900Brazil mars Incorporated13601 Old Cutler RoadMiamiFL 33158USA

Cacao is a crop of global relevance that faces constant demands for improved bean ***,little is known about the genomic regions controlling the crop yield and genes involved in cacao bean ***,to identify the quantitative trait loci(QTL)associated with cacao yield and bean filling,we performed a QTL mapping in a segregating mapping population comprising 459 trees of a cross between‘TSH 1188’and‘CCN 51’.All variables showed considerable phenotypic variation and had moderate to high heritability *** identified 24 QTLs using a genetic linkage map that contains 3526 single nucleotide polymorphism(SNP)*** analysis at the significant QTL region on chromosome IV pointed to the alleles from the maternal parent,‘TSH 1188’,as the ones that affect the cacao yield components the *** recombination events identified within these QTL regions allowed us to identify candidate genes that may take part in the different steps of pod growth and bean *** candidate genes seem to play a significant role in the source-to-sink transport of sugars and amino acids,and lipid metabolism,such as fatty acid *** SNP markers mapped in our study are now being used to select potential highyielding cacao varieties through marker-assisted selection in our existing cacao-breeding experiments.

关键词： breeding mapping linkage

Intraoperative pancreas stump perfusion assessment during pancreaticoduodenectomy:A systematic scoping review

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World Journal of Gastrointestinal Surgery 2023年第8期15卷 1799-1807页

作者： Francis P Robertson Harry V m Spiers Wei Boon Lim Benjamin Loveday keith Roberts Sanjay Pandanaboyana Department of HPB and Transplant Surgery Freeman HospitalNewcastle Upon Tyne NE77DNUnited Kingdom Department of HPB Surgery Addenbrookes HospitalCambridge CB20QQUnited Kingdom Department of General Surgery Royal Melbourne HospitalMelbourne VIC 3050Australia Department of HPB Surgery University Hospitals Birmingham NHS Foundation TrustBirmingham BG152GWUnited Kingdom

BACKGROUND Post-operative pancreatic fistula(POPF)is the primary cause of morbidity following *** of POPF have remained high despite well known risk *** theory that hypoperfusion of the pancreatic stump leads to anastomotic failure has recently gained *** To define the published literature with regards to intraoperative pancreas perfusion assessment and its correlation with *** A systematic search of available literature was performed in November *** extracted included study characteristics,method of assessment of pancreas stump perfusion,POPF and other post-pancreatic surgery specific *** Five eligible studies comprised two prospective non-randomised studies and three case reports,total 156 *** studies used indocyanine green fluorescence angiography to assess the pancreatic stump,with the remaining study assessing pancreas perfusion by visual inspection of arterial bleeding of the pancreatic *** was significant heterogeneity in the definition of *** had a combined POPF rate of 12%;intraoperative perfusion assessment revealed hypoperfusion was present in 39%of patients who developed *** rate of POPF was 11%in patients with no evidence of hypoperfusion and 13%in those with evidence of hypoperfusion,suggesting that not all hypoperfusion gives rise to POPF and further analysis is required to analyse if there is a clinically relevant cut *** variance in practice was seen in the pancreatic stump management once hypoperfusion was *** The current published evidence around pancreas perfusion during pancreaticoduodenectomy is of poor *** does not support a causative link between hypoperfusion and *** well-designed prospective studies are required to investigate this.

关键词： Pancreatico-duodenectomy Post-operative pancreatic fistula Perfusion Indocyanine green Post pancreatectomy pancreatitis

Is salmonid migration at risk from chemical information disruption?

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Aquaculture and Fisheries 2024年第3期9卷 378-387页

作者： keith B.Tierney Gregory G.Pyle Biological Sciences College of Natural and Applied SciencesEdmontonABT6G 2E9Canada School of Public Health College of Health SciencesEdmontonABT6G 1C9Canada Department of Biological Sciences University of LethbridgeLethbridgeABT1K 3M4Canada

Good information is the basis for good *** many invaluable salmon species,chemical information is necessary to guide and fine-tune their migrations to and from freshwater mating grounds.A problem is that salmon of the current world are running a gauntlet of toxic chemicals arising from diverse anthropogenic inputs and these chemicals are known to disrupt *** is sufficient evidence that effluents from cities,mines,agriculture and industry contain chemicals that can rapidly,and sometimes irreversibly,impair the olfactory sense that salmon use to gather *** toxic inputs may not only be strong enough to impair migration,but be strong enough to redirect salmon away from their *** is also evidence that some synthetic chemicals may serve as the basis for ‘new’ information and be useful in making correct migratory *** the plus side,there are examples of new regulations that limit the input of chemicals of known olfactory toxicity,but on the minus side,increased urbanization and global climate change will likely increase the number and/or severity of some neurotoxic *** we identify the specific avenues of chemical risks to information disruption and in so doing prioritize and rank the risks to migrating *** data collected here can be used to lay the foundation for modelling the effects of anthropogenic inputs on information disruption in diverse salmonid species from around the world and therefore help secure their longevity in a changing chemical environment.

关键词： Salmon migration Ocean ranching Chemical information disruption Homing disruption Olfactory toxicity

Strategies for Sustainable Financing of Secondary Education in Sub-Saharan Africa 1

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Classifying coke using CT scans and landmark multidimensional scaling

丛书名： Africa Human Development SeriesEdition

2008年

作者： keith m. Lewin

ISBN: (数字)9780821371169

ISBN: (纸本)9780821371152

Investment in secondary schooling in Sub-Saharan Africa has been neglected since the World Conference on Education for All at Jomtien. The World Education Forum in Dakar began to recognize the growing importance of post-primary schooling for development. Only 25 percent of school-age children attend secondary school in the regionand fewer complete successfully, having consequences for gender equity, poverty reduction, and economic growth. As universal primary schooling becomes a reality, demand for secondary schools is increasing rapidly. Gaps between the educational levels of the labor force in Sub-Saharan Africa and other regions remain large. Girls are more often excluded from secondary schools than boys. Secondary schooling costs are high to both governments and households. This book explores how access to secondary education can be increased. Radical reforms are needed in low-enrollment countries to make secondary schooling more affordable and to provide more access to the majority currently excluded. The report identifies the rationale for increasing access, reviews the status of secondary education in Sub-Saharan Africa, charts the growth needed in different countries to reach different levels of participation, identifies the financial constraints on growth, and discusses the reforms needed to make improved access affordable. The book concludes with a road map of ways forward that increase the probability that more of Africas children will experience secondary schooling.

关键词： Education, Secondary -- Economic aspects -- Africa, Sub-Saharan Education, Secondary -- Africa, Sub-Saharan -- Finance Sustainable development -- Africa, Sub-Saharan

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International Journal of Coal Science & Technology 2023年第1期10卷 160-172页

作者： keith Nesbitt Fayeem Aziz merrick mahoney Stephan Chalup Bishnu P.Lamichhane School of Information and Physical Sciences Universityof NewcastleCallaghanNSWAustralia

One factor that limits development of fundamental research on the infuence of coke microstructure on its strength is the difculty in quantifying the way that microstructure is both classifed and distributed in three *** support such fundamental studies,this study evaluated a novel volumetric approach for classifying small(approx.450μm^(3))blocks of coke microstructure from 3D computed tomography *** automated process for classifying microstructure blocks was *** is based on Landmark multi-Dimensional Scaling and uses the Bhattacharyya metric and k-means *** approach was evaluated using 27 coke samples across a range of coke with diferent properties and reliably identifed 6 ordered class of coke microstructure based on the distribution of voxel intensities associated with structural *** lower class(1–2)subblocks tend to be dominated by pores and thin ***,there is an increase in wall thickness and reduced pore sizes in the higher *** features are also likely to be seen in higher classes(5–6).In general,this approach provides an efcient automated means for identifying the 3D spatial distribution of microstructure in CT scans of coke.

关键词： Coke microstructure Clustering Classifcation Computer tomography

A deep convolutional neural network for real-time full profile analysis of big powder diffraction data

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npj Computational materials 2021年第1期7卷 671-679页

作者： Hongyang Dong keith T.Butler Dorota matras Stephen W.T.Price Yaroslav Odarchenko Rahul Khatry Andrew Thompson Vesna middelkoop Simon D.m.Jacques Andrew m.Beale Antonis Vamvakeros Department of Chemistry University College London20 Gordon StreetLondon WC1H 0AJUnited Kingdom ScimL Scientific Computer DivisionSTFCRutherford Appleton LaboratoryHarwell OX110QXUnited Kingdom Finden Limited Merchant House5 East St Helens StreetAbingdon OX145EGUnited Kingdom National Physical Laboratory Hampton RoadTeddington TW110LWUnited Kingdom Flemish Institute for Technological Research VITO NVBoeretang 200Mol 2400Belgium Research Complex at Harwell Rutherford Appleton LaboratoryHarwell Science and Innovation CampusDidcotOX110FA OxfordshireUnited Kingdom Present address:Diamond Light Source Harwell Science and Innovation CampusDidcotOxfordshire OX110DEUnited Kingdom Present address:The Faraday Institution Quad OneHarwell Science and Innovation CampusOX110RA OxfordshireUnited Kingdom

We present Parameter Quantification Network(PQ-Net),a regression deep convolutional neural network providing quantitative analysis of powder X-ray diffraction patterns from multi-phase *** network is tested against simulated and experimental datasets of increasing complexity with the last one being an X-ray diffraction computed tomography dataset of a multi-phase Ni-Pd/CeO_(2)-ZrO_(2)/Al_(2)O_(3) catalytic material system consisting of ca.20,000 diffraction *** is shown that the network predicts accurate scale factor,lattice parameter and crystallite size maps for all phases,which are comparable to those obtained through full profile analysis using the Rietveld method,also providing a reliable uncertainty measure on the *** main advantage of PQNet is its ability to yield these results orders of magnitude faster showing its potential as a tool for real-time diffraction data analysis during in situ/operando experiments.

关键词： network powder analysis

Lymphoepithelial cysts of the pancreas:a management dilemma

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Hepatobiliary & Pancreatic Diseases International 2014年第5期13卷 539-544页

作者： Julie martin keith J Roberts maria Sheridan Gavin A Falk Daniel Joyce R matthew Walsh Andrew m Smith Gareth morris-Stiff Departments of Pancreatic Surgery St James's University Hospital Departments of Radiology St James's University Hospital Department of General Surgery Section of Surgical Oncology/HPB Cleveland Clinic Foundation

Pancreatic lymphoepithelial cysts（LECs） are rare,benign lesions that are typically unexpected post-operative pathological findings. We aimed to review clinical, radiological and pathological features of LECs that may allow their preoperative diagnosis. Histopathology databases of two large pancreatic units were searched to identify LECs and notes reviewed to determine patient demographic details, mode of presentation, investigations, treatment and outcome. Five male and one female patients were identified. Their median age was 60 years. Lesions were identified on computed tomography performed for abdominal pain in two patients, and were incidentally observed in four patients. Five LECs were located in the tail and one in the body of the pancreas, with a median cyst size of 5 cm. Obtaining cyst fluid was difficult and a largely acellular aspirate was yielded. The pre-operative diagnosis was mucinous cystic neoplasm in all patients. This series of patients were treated distal pancreatectomy and splenectomy. A retrospective review of radiological examinations suggested that LECs have a relatively low signal on T2 imaging and a high signal intensity on T1 weighted images. LECs appear more common in elderly males, and are typically incidental, large, unilocular cysts. Close attention to signal intensity on mRI may allow preoperative diagnosis of these lesions.

关键词： lymphoepithelial cyst pancreas

Immediate and long-term effects of invasive plant species on soil characteristics

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Soil Ecology Letters 2022年第3期4卷 276-288页

作者： Irene m.Unger Robert J.Kremer Kristen S.Veum keith W.Goyne Department of Biology and Chemistry Baker UniversityP.O.Box 65Baldwin CityKS 66006USA School of Natural Resources University of missouri 302 ABNR Bldg.ColumbiaMO 65211USA USDA-ARS Cropping Systems and Water Quality UnitUniversity of Missouri302 ABNR Bldg.ColumbiaMO 65211USA Department of Forest Resources and Environmental Conservation Virginia Tech324 Cheatham HallBlacksburgVA 24061USA

Invasive plant species may alter soil characteristics or interact with the soil microbial community resulting in a competitive *** objectives were to determine:i)if invasive plant species alter soil properties;and ii)the long-term effects of invasive plant species on soil properties and subsequent implications on ecological restoration *** focused on Lespedeza cuneata,a plant that may be *** samples were collected from four locations in Central missouri,USA:an old-field with abundant ***,two reconstructed sites,and a remnant prairie that has never been *** health indictors were used to characterize soil properties at these *** every soil property differed significantly between the unplowed prairie reference site and the other three *** reconstructed sites,however,generally did not differ from the invaded *** results indicate that the reconstructed prairies are not fully *** above-ground traits,such as the plant community structure,appear similar to the prairie,the soil microbial community structure still resembles that of an invaded old-field *** results indicate that more time may be needed before soil microbial populations fully recover after invasive plant removal.

关键词： Sericea lespedeza Legacy effects Soil microorganisms