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Microbial and size characterization of airborne particulate matter collected on sticky tapes along US–Mexico border

Journal of Environmental Sciences 2017年第3期29卷 207-216页

作者： Amir Gonzalez-Delgado Manoj K.Shukla david w.dubois Juan P.Flores-Mdrgez Joel A.Hernandez Escamilla Evangelina Olivas Plant and Environmental Sciences Department New Mexico State UniversityMSC 3Q Skeen Hall Room N 127P.O.Box 30003Las CrucesNM 88003-8003USA Universidad Autonoma de Ciudad Judrez UACJAv.Plutarco Elias Calles 1020Fovisste ChamizalCiudad JudrezChihuahua C.P.32310Mexico

Particulate matter （PM） emissions from various sources can affect significantly human health and environmental quality especially in the Chihuahuan Desert region along US- Mexico border. The objective of this study was to use the low-cost sticky tape method to collect airborne PM for size characterization and identification of fungal spores. Sticky tape samplers were placed at 1.0 and 2.0 m above the ground surface at experimental sites in Ciudad Ju＆ez, Mexico and at 0.6, 1.2 and 1.8 m at New Mexico sites, USA. Soil samples were collected in both countries to determine fungal diversity, texture and moisture content. Dust particles collected from all of the experimental sites had a dominant texture of clay （〈0.002 mm）. The dominant textures identified from soil samples collected from the US and Mexican sites were loam and sandy clay loam, respectively. Alternaria, Penicillium and Fusarium were frequently found funguses in the US sites while Alternaria and Aspergillus were commonly observed in the Mexican sites. The sticky tapes also showed a similar diversity of fungal microorganisms present in the airborne PM at both Mexico and US sites. Alternaria, Penicillium and Aspergillus were the three groups of airborne fungal microorgan- isms consistently present in the US and Mexican sites. The low-cost sticky tape method has the potential to be used for characterizing different airbome microorganisms and dust particles.

关键词： Fungal sporesSticky tapeParticle sizeMicroorganismDust

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Recombinase-mediated Gene Stacking as a Transformation Operating System

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Journal of Integrative Plant Biology 2011年第7期53卷 512-519页

作者： david w.Ow South China Botanical Garden

The current method for combining transgenes into a genome is through the assortment of independent loci, a classical operating system compatible with transgenic traits created by different developers, at different times and/or through different transformation techniques. However, as the number of transgenic loci increases over time, increasingly larger populations are needed to find the rare individual with the desired assortment of transgenic loci along with the non-transgenic elite traits. Introducing a transgene directly into a field cultivar would bypass the need to introgress the engineered trait. However, this necessitates separate transformations into numerous field cultivars, along with the characterization and regulatory approval of each independent transformation event. Reducing the number of segregating transgenic loci could be achieved if multiple traits are introduced at the same time, a preferred option if each of the many traits is new or requires re-engineering. If reengineering of previously introduced traits is not needed, then appending a new trait to an existing locus would be a rational strategy. The insertion of new DNA at a known locus can be accomplished by site- specific integration, through a host-dependent homology-based process, or a heterologous site-specific recombination system. Here, we discuss gene stacking through the use of site-specific recombinases.

关键词： site-specific recombination transgenic plants DNA integration marker removal Cre-lox

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A Review of the Taxonomy and Palaeoecology of the Anurognathidae(Reptilia,Pterosauria)

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1676-1692页

作者： david w.E.HONE School of Biological and Chemical Sciences Queen Mary University of LondonLondonE14NSUK

The anurognathids are an enigmatic and distinctive clade of small,non-pterodactyloid pterosaurs with an unusual combination of anatomical traits in the head,neck,wings and *** are known from very limited remains and few have been described in detail,and as a result,much of their biology remains *** is despite their importance as potentially one of the earliest branches of pterosaur evolution or even lying close to the origins of *** review covers the taxonomy and palaeoecology of the anurognathids,which remain an interesting branch of pterosaurian evolution.

关键词： non-pterodactyloid palaeobiology flight Ornithodira

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Beyond the burn: Studies on the physiological effects of flamethrowers during world war Ⅱ

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Military Medical Research 2020年第3期7卷 303-311页

作者： david w.Van wyck 4/3 SFG(A)Bldg Z-4157 South Post Rd Fort BraggNC 28310USA

Flamethrowers are widely considered one of warfare’s most controversial weapons and are capable of inflicting gruesome physical injuries and intense psychological *** being the last of the major combatants in world warⅡ(wwⅡ)to develop them,the *** quickly became the most frequent and adept operator of portable *** gave the *** ample opportunity to observe the effects of flamethrowers on enemy ***,while most people in modern times would consider immolation by flamethrower to be an unnecessarily painful and inhumane way to inflict casualties,immolation was,at one point during wwⅡ,referred to as"mercy killing"by the *** warfare Service(CwS).This mischaracterization arose from a series of firsthand accounts describing what were believed to be quick,painless,and unmarred deaths,as well as from a poor and incomplete understanding of flamethrower *** a result,indirect mechanisms such as hypoxia and carbon monoxide poisoning were generally absent from accounts of the flamethrower’s fatal *** was not until several years after flamethrowers were introduced to the frontlines that the CwS and National Defense Research Committee(NDRC)conducted a series of tests to better understand the physiological and toxicological effects of *** article examines how the initial absence of scientific data on the physiologic effects of flamethrowers led to an inaccurate understanding of their lethality,and bizarre claims that one of history’s most horrific instruments of war was considered one of the more"humane"weapons on the battlefield.

关键词： Flamethrower Burns Carbon monoxide Asphyxiation Hypoxia Chemical warfare

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Modeling and optimization of the cyclic steady state operation of adsorptive reactors

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1321-1329页

作者： Mamoon Hussainy david w.Agar Technical University of Dortmund Faculty of Bio-and Chemical EngineeringLaboratory for Chemical Reaction Engineering

Adsorptive reactors(AR),in which an adsorptive functionality is incorporated into the catalytic reactors,offer enhanced performance over their conventional counterparts due to the effective manipulation of concentration and temperature *** operation of these attractive reactors is,however,inherently unsteady state,complicating the design and operation of such sorption-enhanced *** order to capture,comprehend and capitalize upon the rich dynamic texture of adsorptive reactors,it is necessary to employ cyclic steady state algorithms describing the entire reaction-adsorption/desorption *** stability of this cyclic steady state is of great importance for the design and operation of adsorptive *** this paper,the cyclic steady state of previously proposed novel adsorptive reactor designs has been calculated and then optimized to give maximum space–time *** results obtained revealed unambiguously that an improvement potential of up to multifold level could be attained under the optimized cyclic steady state *** additional improvement resulted from the reduction of the regeneration time well below the reaction-adsorption time,which means,in turn,more space–time yield.

关键词： Adsorptive reactors Multifunctional reactors Cyclic steady state Claus reaction Deacon reaction

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More than mimicry？ Evaluating scope for flicker-fusion as a defensive strategy in coral snake mimics

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Current Zoology 2014年第1期60卷 123-130页

作者： Georgia C. TITCOMB david w. KIKUCHI david w. PFENNIG Department of Biology University of North Carolina at Chapel Hill Chapel Hill NC 27599-3280

Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a ＂flicker-fusion＂ effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake＇s bands must transition faster than the critical flicker-fusion rate at which a predator＇s photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. we tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. we found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry

关键词： Coral snake mimicry Flicker-fusion effect CFF Kingsnake Defensive strategy

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Pterosaur Research:Recent Advances and a Future Revolution

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1366-1376页

作者： david w.E.HONE Department of Earth Sciences University of Bristol School of Biological and Chemical Sciences Queen Mary University of London

In the years since the first description of a pterosaur specimen in 1784, pterosaur research has inevitably advanced considerably. However the last decade has arguably seen a much greater increase in our knowledge than the preceding two centuries. Since the turn of the new millennium, more than 40 new pterosaur genera and species have been described and whole new clades have been discovered, in addition to much new data being developed on pterosaur anatomy, functional morphology, palaeobiology, systematics, ecology and more. we are perhaps at the start of a golden age of pterosaur research and much as the dinosaurs underwent a revolution in the 1970s through to the early 1990s, now the Pterosauria are taking their turn. There is also a new and wider interest in pterosaur work as it attracts both more researchers and greater public interest. Pterosaurs appear to be an increasingly popular aspect of paleontology in popular culture and of interest to the media, both mainstream and digital.

关键词： paleontology Pterosauria science history of research academia

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Public Health and Private Charity in Northeast China, 1905-1945

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Frontiers of History in China 2014年第4期9卷 506-533页

作者： Thomas david dubois College of Asia and the Pacific Australian National University Canberra ACT 0200 Australia

Medical charity in northeast China evolved through the confluence of three processes： the foundation of state medicine, the legal and political transformation of private charities, and the militarized competition for influence between China and Japan. Following the plague of 1910, a series of Chinese regimes began building medical infrastructure in areas under their control, but their ultimate inability to establish a comprehensive public health program left private charities to fill the gaps. In contrast, the Japanese administered concessions in Kant6 and along the South Manchuria Railway instituted a farsighted and multivaleneed medical policy. The Japanese model did not merely tolerate medical charities, it reserved for them a very specific role in the larger strategic framework of healthcare provision. Under the client state of ＂Manzhouguo,＂ the Japanese model further evolved to channel medical voluntarism into a hybrid state-charitable sector.

关键词： Manchuria charity medicine epidemic disease Japan sovereignty,social engineering

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Inducible competitors and adaptive diversification

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Current Zoology 2013年第4期59卷 537-552页

作者： Beren w. ROBINSON david w. PFENNIG Department of Integrative Biology University of Guelph Guelph Ontario N 1G 2W 1 Canada Department of Biology University of North Carolina Chapel Hill NC 27599 USA

Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of ＂inducible competitors＂. Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity

关键词： Phenotypic plasticity Competition Adaptive radiation Character displacement Genetic assimilation Resourcepolymorphism

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Factors influencing mercury accumulation in three species of forage fish from Caddo Lake, Texas, USA

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Journal of Environmental Sciences 2010年第8期22卷 1158-1163页

作者： Matthew M Chumchal Ray w Drenner david R Cross K david Hambright Department of Biology Texas Christian University 2800 S. University Dr Department of Psychology Texas Christian University 2800 S. University Dr Program in Ecology and Evolutionary Biology Biological Station and Department of Zoology 730 Van Vleet Oval University of Oklahoma

Most studies that have examined mercury （Hg） contamination of fish have focused on game species feeding near the top of the food web, while studies that examine forage fish that feed near the base of the food web are rare. we conducted a survey of Hg contamination in three species of forage fish, brook silverside （Labidesthes sicculus）, threadfin shad （Dorosoma petenense） and gizzard shad （Dorosoma cepedianum）, from Caddo Lake, Texas, USA and found species-specific differences in Hg concentrations. we examined total length, age, trophic position （determined using δ15N）, and growth rate of forage fish as factors that could have influenced within-and between-species differences in Hg concentration. Total length and age were the best predictors of within-species differences in Hg concentration. Between-species differences in Hg concentrations were most strongly influenced by trophic position.

关键词： mercury trophic position forage fish

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