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Host-environment mismatches associated with subalpine fir decline in Colorado

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Journal of Forestry Research 2016年第5期27卷 1177-1189页

作者： Robin M. Reich john e. Lundquist Kristina Hughes Colorado State University Fort Collins CO USA U.S. Forest Service Anchorage Anchorage AK 99501 USA

Subalpine fir decline （SFD） has killed more trees in Colorado＇s high elevation forests than any other insect or disease problem. The widespread nature of this disorder suggests that the cause involves climatic factors. We examined the influence of varying combinations of average annual temperature and precipitation on the incidence and distribution of SFD. Climatic transition matrices generated in this study indicate that most healthy trees are found in climatic zones with moderate to low temperatures and high precipitation; whereas, SFD occurs mostly in zones of moderate temperatures and moderate precipitation. The contrasting distributions define an environmental mismatch. Forests matched with favorable climatic conditions thrive; those that are mismatched can become vulnerable to decline disease.

关键词： Abiotic disorder Climate stress High elevation forests Forest disease - Subalpine fir

Asymmetric reinforcement in Lucania killifish:assessing reproductive isolation when both sexes choose

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Current Zoology 2021年第2期67卷 215-224页

作者： Michelle e.ST.john Rebecca C.FULLeR School of Integrative Biology University of liois Urbana-ChampaignChampaignIL 61820USA

Reinforcement can occur when maladaptive hybridization in sympatry favors the evolution of con-specific preferences and target traits that promote behav ioral isolation(BI).In many systems,enhanced BI is due to increased female preference for *** others,BI is driven by male preference,and in other systems both sexes exert *** of these patterns can be atributed to classic sex-specific costs and benefits of ***,sex differences in conspecific preference can emerge due to asymmetric postzygotic isolation(e.g.,hybrid offspring from female A × male B have lower fitness than hybrid offspring from female B × male A),which can lead to asymmetric BI(e.g.,female A and male B are less likely to mate than female B and male A).Understanding reinforcement requires understanding how conspecific preferences evolve in ***,estimating conspecific preferences can be difficult when both sexes are *** this study,we use Lucania killifish to test the hypothesis that patterns of reinforcement are driven by asymmetric postzygotic isolation between *** true,we predicted that sympatric female Lucania goodei and sympatric male *** should have lower levels of BI compared with their sympatric counterparts,as they produce hybrid offspring with the highest *** address the problem of measuring BI when both sexes are choosy,we inferred the contribution to BI of each partner using assays where one sex in the mating pair comes from an allopatric population with potentially low preference,whereas the other comes from a sympatric population with high *** one hybrid cross direction,we found that both female *** and male *** have high contributions to BI in *** the other hybrid cross direction,we found that only female *** contribute to *** male *** readily engaged in hybrid spawnings with allo-patric *** *** results indicate that both asymmetric postzygotic isolation

关键词： reinforcement behavioral isolatin female mate choice male mate choice asymmetric costs to hybridization

From Cape Town to Cambridge: Orthopaedic trauma in contrasting environments

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World Journal of Orthopedics 2016年第5期7卷 308-314页

作者： john e Lawrence Vikas Khanduja Department of Trauma and Orthopaedics Addenbrooke's Hospital Cambridge University Hospitals NHS Foundation Trust

AIM: To compare the trauma experience gained by a trainee at a United Kingdom major trauma centre and a secondary level hospital in South ***: A profile of inpatient trauma cases during a five-week period in Addenbrooke's Hospital, Cambridge and Somerset Hospital, Cape Town was created. This was achieved by recording various parameters for each patient admitted including age, gender, injury, mechanism of injury and postal/area code. This, together with details of the departments themselves, allows a comparison of the amount and variety of orthopaedic trauma cases experienced by an individual trainee in each setting. ReSULTS: The trauma profiles differed significantly. Patients in Cape Town were younger and more likely to be male. In the young, injury in Cape Town was more likely to occur due to assault or being struck by a vehicle, whilst patients in Cambridge were more likely to be injured whilst in a vehicle or in high energy falls. In older patients, trauma at both centres was almost exclusively due to mechanical falls. In a given age group, injuries at the two centres were similar, however the majority of patients admitted to Addenbrooke's were elderly, resulting in less variation in the overall injury ***: The trauma profile of a major trauma centre in the United Kingdom is less varied than that of a South African secondary centre, with significantly fewer cases per surgeon. This suggests a more variedtraining experience in the developing world with a greater caseload.

关键词： Comparative epidemiology Developing world Trauma Training

environment as the Stage for economic Actors

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Chinese Journal of Population,Resources and environment 2007年第1期5卷 3-8页

作者： john e Coulter Shi Lei Samantha Jenkins Suite 605 Silver Tower No. 2 Dong San Huan Bei Road Chaoyang Beijing 100027 China SePA Key Laboratory on eco-industry Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Department of Technology Mathematics and CS University West Trollhatten SE 461 29 Sweden

The relative importance of economics and environment in debate may soon be reversed due to the influence of three fac- tors. Firstly, in the global economy it is hard to hide the unwanted products of economic processes. Secondly, huge advances in sci- ence will reduce the imperfect knowledge of markets, making some monitoring and analyzing tools show the design of sensible and equitable livelihood in communities, which is more important than the motivation of maximising profits for some individuals or firms. Thirdly, China, as the last major player on the planet to take on economic growth, comes from traditions fundamentally differ- ent from those economies that have experienced the Industrial Revolution previously. Its challenges with sustainability and en- vironmental conservation predate Western economics by millennia, and it is implementing policies domestically and starting to work on the world stage that acknowledges that the surroundings are the host for any economic and socio-political system.

关键词： economics market entropy China

Development of Shallow Footing Anti-Ram Bollard System Through Modeling and Testing

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Transactions of Tianjin University 2006年第B09期12卷 46-50页

作者： CRAWFORD john e Karogozian & Case 2550 N.Hollywood WaySuite 500BurbankCA 91505USA

In past terrorist attacks, vehicle borne improvised explosive devices (VBIeD) have been the primary manner of attacking buildings and infrastructures. Preventing unauthorized vehicles from approaching a protected area with anti-ram systems would maintain an established standoff distance against moving and stationary vehicles and consequently reduce blast and debris threats. This strategy has been considered the first line of defence against terrorists. Several types of anti-ram devices have been developed in accordance with U. S. Department of State K-rating criteria, for example, wedge barriers, rising beams, sliding/swing gates, and drop arms. However, these devices typically need a deep foundation for installation and can't be implemented into many locations where a depth of excavation is limited in order to protect utility lines of buildings and infrastructures. This paper presents a recent development of a series of shallow footing anti-ram bollard systems (SFABS) that can satisfy K-12 rating with only five-inch thick footing. A high-fidelity physics based finite element technique with a vehicle crash model is used for predicting anti-ram capacity and determining design parameters of the SFABS. Full-scale vehicle crash tests of the developed SFABS systems have been carried out to validate the design and analysis.

关键词： anti-ram bollard shallow footing crash testing finite element analysis

effect of pneumatic compression therapy on lymph movement in lymphedema-affected extremities,as assessed by near-infrared fuorescence lymphatic imaging.

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Journal of Innovative Optical Health Sciences 2017年第2期10卷 110-123页

作者： Melissa B.Aldrich Deborah Gross john Rodney Morrow Caroline e.Fife john C.Rasmussen Center for Molecular Imaging The Brown Institute for Molecular Medicine UTHealth HoustonTexasUSA Mego Afek/Lympha Press USA Freehold New JerseyUSA CHI St.Luke's Health The Woodlands Hospital The Woodlands TexasUSA

Previous studies have shown cost effectiveness and quality-of-life benefit of pneumatic compression therapy(PCT)for lymphedema(Le).Insurers,such as the Centers for Medicare/Medicaid(CMS),however,desire visual proof that PCT moves *** infrared fuorescence lymphatic imaging(NIRFLI)was used to visualize lymphatic anatomy and function in four subjects with primary and cancer treatment-related Le of the lower extremities before,during,and after *** transparent and windowed PCT garments allowed visualization of lymph movement during single,1h PCT treatment *** revealed significant extravascular and lymphatic vascular movement of intradermally injected dye in all *** one subject with sufficient patent lymphatic vessels to allow quantification of lymph pumping velocities and frequencies,these values were significantly increased during and after PCT as compared to pre-treatment *** contractile activity in patent lymphatic vessels occurred in concert with the sequential cycling of *** visualization revealed increased lymphatic function,during and after PCT therapy,in all Le-affected *** studies are warranted to assess the effects of PCT pressure and sequences on lymph uptake and movement.

关键词： Lymphedema pneumatic compression therapy near-infrared fAuorescence

Rare case of tibial hemimelia,preaxial polydactyly,and club foot

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World Journal of Clinical Cases 2016年第12期4卷 401-408页

作者： Guinevere Granite john e Herzenberg Ronald Wade Department of Anatomy and Neurobiology School of MedicineUniversity of Maryland Rubin Institute for Advanced Orthopedics Sinai Hospital of Baltimore Department of Anatomical Services University of Maryland

A seven-month old female presented with left tibial hemimelia(or congenital tibial aplasia; Weber type VIIb, Jones et al type 1a), seven-toed preaxial polydactyly, and severe club foot(congenital talipes equinovarus). Definitive amputation surgery disarticulated the lower limb at the knee. This case report describes the anatomical findings of a systematic post-amputation examination of the lower limb's superficial dissection, X-ray s, and computed to mography (CT) scans. From the X-rays and CT scans, we found curved and overlapping preaxial supernumerary toes, hypoplastic first metatarsal, lack of middle and distal phalanges in one supernumerary toe, three tarsal bones, hypoplastic middle phalanx and no distal phalanx for fourth toe, andno middle or distal phalanges for fifth toe. The fibula articulated with the anteromedial calcaneus and the tibia was completely absent. We identified numerous muscles and nerves in the superficial dissection that are described in the results section of the case report. Due to the rarity of this combination of anatomical findings, descriptions of such cases are very infrequent in the literature.

关键词： Club foot Congenital talipes equinovarus Preaxial polydactyly Tibial hemimelia Congenital tibial aplasia

A unified intrinsic functional expansion theory for solitary waves

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Acta Mechanica Sinica 2005年第1期21卷 1-15页

作者： Theodore Yaotsu Wu john Kao Jin e.Zhang California Institute of Technology Pasadena.CA 91125U.S.A.FellowInstitute of MechanicsChinese Academy of SciencesBeijing 100080China Warner Brothers GlendaleCA 91203.U.S.A. The university of Hong Kong.Pokfulam Road.Hong Kong SAR.China

A new theory is developed here for evaluating solitary waves on water, with results of high accuracy uniformly valid for waves of all heights, from the highest wave with a corner crest of 120 down to very low ones of diminishing height. Solutions are sought for the euler model by employing a unified expansion of the logarithmic hodograph in terms of a set of intrinsic component functions analytically determined to represent all the intrinsic properties of the wave entity from the wave crest to its outskirts. The unknown coefficients in the expansion are determined by minimization of the mean-square error of the solution, with the minimization optimized so as to take as few terms as needed to attain results as high in accuracy as attainable. In this regard, Stokess formula, F2= tan , relating the wave speed (the Froude number F) and the logarithmic decrement of its wave field in the outskirt, is generalized to establish a new criterion requiring (for minimizing solution error) the functional expansion to contain a finite power series in M terms of Stokess basic term (singular in ), such that 2M is just somewhat beyond unity, i.e. 2M1. This fundamental criterion is fully validated by solutions for waves of various amplitude-to-water depth ratio =a/h, especially about 0.01, at which M=10 by the criterion. In this pursuit, the class of dwarf solitary waves, defined for waves with 0.01, is discovered as a group of problems more challenging than even the highest wave. For the highest wave, a new solution is determined here to give the maximum height hst=0.8331990, and speed Fhst=1.290890, accurate to the last significant figure, which seems to be a new record.

关键词： Solitary waves on water Unified intrinsic functional expansion theory exact solutions High-accuracy computation of waves of arbitrary height Mass and energy transfer

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