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Natural Science 2012年第4期4卷 216-232页

作者： john j. Wille Bioderm Technologies Inc. Chesterfield UK

A survey of zoological literature affirmed the wide occurrence of Fibonacci numbers in the organization of acellular and prokaryotic life forms as well as in some eukaryotic protistans and in the embryonic development and adult forms of many living and fossil remains of metazoan animals. A detailed comparative analysis of the axial skeleton of a fossil fish and humans revealed a new rule of the “nested triad” of bones organized along the proximal to distal axis of limb appendages. This growth pattern and its ubiquity among living vertebrates appear to underlie a profound rule of pattern formation that is dictated in part by the genetics and epigenetic mechanisms of stem cell clonal development.

关键词： Animal Body Plan Fibonacci Numbers (n) Hox Genes Nested Triads Phylogeny Recursive Transition Networks Segmentation

A Bayesian Network Approach for Offshore Risk Analysis Through Linguistic Variables

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China Ocean Engineering 2007年第3期21卷 371-388页

作者： Ren j. Wang j. j.nkinson I. Xu D. L. Yang j. B. School of Engineering Liverpool John Moores University Liverpool L 3 3 AF UK Manchester Business School The University of Manchester Manchester M 60 1 QD UK

This paper presents a new approach for offshore risk analysis that is capable of dealing with linguistic probabilities in Bayesian networks （ BNs）. In this paper, linguistic probabilities are used to describe occurrence likelihood of hazardous events that may cause possible accidents in offshore operations. In order to use fuzzy information, an f-weighted valuation function is proposed to transform linguistic j.dgements into crisp probability distributions which can be easily put into a BN to model causal relationships among risk factors. The use of linguistic variables makes it easier for human experts to express their knowledge, and the transformation of linguistic j.dgements into crisp probabilities can significantly save the cost of computation, modifying and maintaining a BN model. The flexibility of the method allows for multiple forms of information to be used to quantify model relationships, including formally assessed expert opinion when quantitative data are lacking, or when only qualitative or vague statements can be made. The model is a modular representation of uncertain knowledge caused due to randomness, vagueness and ignorance. This makes the risk analysis of offshore engineering systems more functional and easier in many assessment contexts. Specifically, the proposed f-weighted valuation function takes into account not only the dominating values, but also the a-level values that are ignored by conventional valuation methods. A case study of the collision risk between a Floating Production, Storage and Off-loading （FPSO） unit and the anthorised vessels due to human elements during operation is used to illustrate the application of the proposed model.

关键词： Risk analysis fiweighted valuation function Bayesian networks fuzzy number linguistic probability off-shore engineering systems

Dielectric confinement on exciton binding energy and nonlinear optical properties in a strained Zn_(1-x_(in))Mg_(x(in))Se/Zn_(1-x(out))Mg_(x(out))Se quantum well

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j.urnal of Semiconductors 2012年第9期33卷 1-7页

作者： j.Abraham Hudson Mark A.john Peter Department of Physics NPR Arts&Science CollegeNathamDindigul-624401India Department of Physics Government Arts CollegeMelur-625106MaduraiIndia

The band offsets for a Zn1-xin Mgxin Se/Zn1-xout Mgxout Se quantum well heterostructure are determined using the model solid theory. The heavy hole exciton binding energies are investigated with various Mg alloy contents. The effect of mismatch between the dielectric constants between the well and the barrier is taken into account. The dependence of the excitonic transition energies on the geometrical confinement and the Mg alloy is discussed. Non-linear optical properties are determined using the compact density matrix approach. The linear, third order non-linear optical absorption coefficient values and the refractive index changes of the exciton are calculated for different concentrations of magnesium. The results show that the occurred blue shifts of the resonant peak due to the Mg incorporation give the information about the variation of two energy levels in the quantum well width.

关键词： interband emission energy exciton binding energy quantum well

Potential influence of wildfire in modulating climate-induced forest redistribution in a central Rocky Mountain landscape

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Ecological Processes 2017年第1期6卷 52-68页

作者： john L.Campbell Douglas j.Shinneman Department of Forest Ecosystems and Society Oregon State UniversityCorvallisORUSA U.S.Geological Survey Forest and Rangeland Ecosystem Science CenterBoiseIDUSA.

Introduction:Climate change is expected to impose significant tension on the geographic distribution of tree ***,tree species range shifts may be delayed by their long life spans,capacity to withstand long periods of physiological stress,and dispersal *** could theoretically break this biological inertia by killing forest canopies and facilitating species redistribution under changing *** investigated the capacity of wildfire to modulate climate-induced tree redistribution across a montane landscape in the central Rocky Mountains under three climate scenarios(contemporary and two warmer future climates)and three wildfire scenarios(representing historical,suppressed,and future fire regimes).Methods:Distributions of four common tree species were proj.cted over 90 years by pairing a climate niche model with a forest landscape simulation model that simulates species dispersal,establishment,and mortality under alternative disturbance regimes and climate ***:Three species(Douglas-fir,lodgepole pine,subalpine fir)declined in abundance over time,due to climate-driven contraction in area suitable for establishment,while one species(ponderosa pine)was unable to exploit climate-driven expansion of area suitable for *** fire frequency accelerated declines in area occupied by Douglas-fir,lodgepole pine,and subalpine fir,and it maintained local abundance but not range expansion of ponderosa ***:Wildfire may play a larger role in eliminating these conifer species along trailing edges of their distributions than facilitating establishment along leading edges,in part due to dispersal limitations and interspecific competition,and future populations may increasingly depend on persistence in locations unfavorable for their establishment.

关键词： Forest disturbance Wildfire Climate change Central Rocky Mountains Climate niche Species migration Species distribution

Alternative expressions for stand diameter in complex forests

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Forest Ecosystems 2023年第3期10卷 328-336页

作者： Mark j.Ducey john A.Kershaw j.. Department of Natural Resources and the Environment University of New HampshireDurhamNHUSA Faculty of Forestry and Environmental Management University of New BrunswickFrederictonNBCanada

Quadratic mean diameter is the most frequently reported descriptor of the diameter distribution of *** such,it is often used as an indicator of forest stand structure,developmental stage,and ecological and economic ***,quadratic mean diameter can be heavily influenced by the presence or absence of large numbers of small stems in lower canopy strata,and it is also sensitive to left-truncation of the diameter distribution,making its interpretation across inventories with different protocols ***,we examine three alternative expressions of stand diameter:the arithmetic and quadratic mean diameter of the thickest 100 trees per hectare,and the basal area-weighted mean *** data from the United States Forest Inventory and Analysis program for New York and New England,these alternative expressions showed closer correlation with multiple stand structural variables than did quadratic mean diameter,including merchantable cubic and board foot volume per hectare,aboveground live tree carbon per hectare,and total number of live and dead standing trees greater than 40 cm diameter at breast height per hectare(previously proposed as an index of old-growth structure).Arithmetic and quadratic mean diameter of the thickest 100 trees per hectare showed nearly identical performance,and the strongest correlations across the *** develop closed-form expressions for these variables when the diameter distribution is a Weibull,and illustrate their behavior relative to quadratic mean diameter for that *** the reasons for prevalence of quadratic mean diameter as an indicator remain valid,we suggest that these alternative measures should be more widely reported and analyzed to give a more informative depiction of stand structure and development in complex forests.

关键词： Forest structure Diameter at breast height Weibull distribution

Update on the management of the gastrointestinal effects of radiation

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World j.urnal of Gastrointestinal Oncology 2021年第5期13卷 400-408页

作者： Hannah McCaughan Stephen Boyle john j.McGoran Department of Gastroenterology Altnagelvin Area HospitalLondonderry BT476SBUnited Kingdom

Radiation therapy is a long-established and essential modality in the treatment of many *** is well known that tissue within a field of radiation can suffer indiscriminate effects,leading to acute and chronic *** gastrointestinal tract may be adversely affected by *** the mouth to the rectum,patients can experience troublesome symptoms that require the concerted input of specialist *** range from nursing care,dietetic optimization,pharmacological management,and mechanical procedures through endoscopy and *** evidence exists mainly for radiation induced effects in four distinct areas of the gastrointestinal tract:oral mucosa,esophagus,small bowel,and *** review explores the experiences of oncology and gastrointestinal teams in managing the most common conditions and some of the different practices for radiation associated morbidity.

关键词： Radiation Stricture Endoscopy

Separations of Metal Ions Using Ionic Liquids: The Challenges of Multiple Mechanisms

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Tsinghua Science and Technology 2006年第2期11卷 188-193页

作者： Violina A. Cocalia john D. Holbrey Keith E. Gutowski Nicholas j. Bridges Robin D. Rogers Department of Chemistry and Center for Green Manufacturing The University of Alabama Tuscaloosa AL 35487 USA

Ionic liquids are a distinct sub-set of liquids, comprising only of cations and anions, often with negligible vapor pressure. As a result of the low or non-volatility of these fluids, ionic liquids are often considered in liquid/liquid separation schemes where the goal is to replace volatile organic solvents. Unfortunately, it is often not yet recognized that the ionic nature of these solvents can result in a variety of extraction mechanisms, including solvent ion-pair extraction, ion exchange, and simultaneous combinations of these. This paper discusses current ionic liquid-based separations research where the effects of the nature of the solvent ions, ligands, and metal ion species were studied in order to be able to understand the nature of the challenges in utilizing ionic liquids for practical applications.

关键词： metal ion liquid-liquid separation ionic liquid solvent extraction

Species Concepts as Applied to the Whitefly Bemisia tabaci Systematics:How Many Species Are There?

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j.urnal of Integrative Agriculture 2012年第2期11卷 176-186页

作者： LIU Shu-sheng john Colvin Paul j.De Barro Key Laboratory of Agricultural Entomology Ministry of Agriculture~Institute of lnsect Sciences Zhejiang University Hangzhou 310058 P.R. China Natural Resources Institute University of Greenwich Kent ME4 4TB United Kingdom CSIRO Ecosystem Sciences Brisbane QLD 4001 Australia

The worldwide distribution and extensive genetic diversity of the whitefly,Bemisia tabaci,has long been ***,the levels of separation within *** and the nomenclature of the various genetic groups have been a subj.ct of *** phylogenetic analyses indicate that *** is a complex composed of 28 morphologically indistinguishable *** this article,we first review the debate and difficulties associated with ***＇s taxonomy and systematics,and argue for the need to apply the biological species concept in order to elucidate ***＇s *** summarize the accumulated genetic and behavioural data on reproductive incompatibilities evident amongst phylogenetic mtCOI groups of *** studies have been conducted with 14 of the 28 putative species covering 54 reciprocal inter-species pairs,and observations on mating behaviour have been conducted for seven species *** from both crossing trials and behavioural observations indicate a consistent pattern of reproductive isolation among the putative *** then discuss the technical and conceptual complexities associated with crossing experiments and behavioural observations designed to reveal reproductive ***,we elaborate on a strategy for further clarifying the pattern of reproductive isolation between *** groups and propose future research directions on the systematics of this complex.

关键词： whitefly systematics biological species cryptic species phylogenetic species reproductive isolation mating behavior taxonomy

The role of organic electron donors in the initiation of BHAS base-induced coupling reactions between haloarenes and arenes

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Science China Chemistry 2019年第11期62卷 1425-1438页

作者： Andrew j.Smith Darren L.Poole john A.Murphy Department of Pure and Applied Chemistry University of StrathclydeStrathclydeGlasgow G11XLUnited Kingdom Flexible Discovery Unit GlaxoSmithKline Medicines Research CentreStevenageSG12NYUnited Kingdom

Coupling reactions between haloarenes and arenes(including heteroarenes)that are conducted without added transition metals but in the presence of KOtBu or NaOtBu,have been a topic of great interest since their discovery in *** organic structures act as additives that assist these *** additives are converted into organic electron donors by the butoxide base and this leads to initiation of the coupling reactions,which proceed by radical chain *** review provides an overview of the initiation stages of these reactions.

关键词： organic electron donor potassium tert-butoxide electron transfer base-promoted homolytic aromatic substitution(BHAS) coupling benzyne

Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study

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Asian j.urnal of Andrology 2021年第5期23卷 537-540页

作者： john K Amory Charles H Muller Thomas j.Walsh Department of Medicine University of WashingtonSeattleWA 98195USA Department of Urology University of WashingtonSeattleWA 98195USA

The treatment of men with infertility from azoospermia is *** some men with severe oligozoospermia improve sperm output during treatment with isotretinoin,we treated nine men with azoospermia with isotretinoin to determine if azoospermic men would also respond to isotretinoin *** of these men who had a previous negative testicular sperm extraction(TESE)was found to have an area of sperm production on a postisotretinoin testicular *** man achieved a pregnancy and a live birth of a healthy,term daughter after in vitro fertilization coupled with intracytoplasmic sperm inj.ction(IVF/ICSI).A second subj.ct had a positive TESE after treatment as *** study of isotretinoin therapy in men with azoospermia undergoing testicular sperm harvesting procedures is warranted.

关键词： treatment inj.ction pregnancy