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Bounding species distribution models

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Current Zoology 2011年第5期57卷 642-647页

作者： Thomas j. STOHLGREN Catherine S. j.RNEVICH Wayne E. ESAIAS jeffrey T. MORISETTE Fort Collins Science Center U.S. Geological Survey 2150 Centre Avenue Fort Collins CO 80526USA Code 614.5. NASA/Goddard Space Flight Center. Greenbelt MD 20771 USA

Species distribution models are increasing in popularity for mapping suitable habitat for species of management con- cern. Many investigators now recognize that extrapolations of these models with geographic information systems （GIS） might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for ＂clamping＂ model extrapolations. We relied on two commonly used modeling approaches： classification and regression tree （CART） and maximum entropy （Maxent） models, and we tested a simple alteration of the model extrapolations, bounding ex- trapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suit-able habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 （5）： 642-647,2011].

关键词： Niche models Geographic information systems Extrapolation Clamping

Micro-optical fabrication by ultraprecision diamond machining and precision molding

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Frontiers of Mechanical Engineering 2017年第2期12卷 181-192页

作者： Likai LI Neil j. NAPLES jeffrey W. ROBLEE Allen Y. YI Department of Integrated System Engineering The Ohio StateUniversity Columbus OH 43210 USA Nistica Inc. Bridgewater NJ 08807 USA Ametek Precitech Keene NH 03431 USA

Ultraprecision diamond machining and high volume molding for affordable high precision high performance optical elements are becoming a viable process in optical industry for low cost high quality microoptical component manufacturing. In this process, first high precision microoptical molds are fabricated using ultraprecision single point diamond machining followed by high volume production methods such as compression or inj.ction molding. In the last two decades, there have been steady improvements in ultraprecision machine design and performance, particularly with the introduction of both slow tool and fast tool servo. Today optical molds, including freeform surfaces and microlens arrays, are routinely diamond machined to final finish without post machining polishing. For consumers, compression mold- ing or inj.ction molding provide efficient and high quality optics at extremely low cost. In this paper, first ultrapreci- sion machine design and machining processes such as slow tool and fast too servo are described then both compression molding and inj.ction molding of polymer optics are discussed. To implement precision optical manufacturing by molding, numerical modeling can be included in the future as a critical part of the manufacturing process to ensure high product quality.

关键词： ultraprecision machining slow tool servo fast tool servo compression molding inj.ction molding,microlens arrays optical fabrication

Effects of Gamma Irradiation for Sterilization on Aqueous Dispersions of Length Sorted Carbon Nanotubes

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Nano Research 2011年第4期4卷 393-404页

作者： jeffrey A. Fagan Nancy j. Lin Rolf Zeisler Angela R. Hight Walker Polymers Division National Institute of Standards and Technology Gaithersburg MD 20899 USA Analytical Chemistry Division National Institute of Standards and Technology Gaithersburg MD 20899 USA Optical Technology Division. National Institute of Standards and Technology Gaithersburg MD 20899. USA

There is currently great interest in the potential use of carbon nanotubes as delivery vessels for nanotherapeutics and other medical applications. However, no data are available on the effects of sterilization methods on the properties of nanotube dispersions, the form in which most medical applications will be processed. Here we show the effects of gamma irradiation from a 60Co source on the dispersion and optical properties of single-wall carbon nanotubes in aqueous dispersion. Samples of different length-refined populations were sealed in ampoules and exposed to a dose of approximately 28 kGy, a level sufficient to ensure sterility of the dispersions. In contrast to literature results for solid-phase nanotube samples, the effects of gamma irradiation on the dispersion and optical properties of the nanotube samples were found to be minimal. Based on these results, gamma irradiation appears sufficiently non-destructive to be industrially useful for the sterilization of nanotube dispersions.

关键词： Nanotube single-wall nanotube (SWNT) single-wall carbon nanotube (SWCNT) gamma irradiation sterilization dispersion

Sexual selection on color and behavior within and between cichlid populations： Implications for speciation

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Current Zoology 2012年第3期58卷 475-483页

作者： Michael j.PAUERS jeffrey S.MCKINNON Section of Vertebrate Zoology The Milwaukee Public MuseumMilwaukeeWI 53233USA Department of Biology N108 Howell Science ComplexEast Carolina UniversityGreenvilleNC 27858-4353USA

Sexual selection is widely viewed as playing a central role in haplochromine cichlid speciation. Hypothetically, once divergent mate preferences evolve among populations of these fishes, reproductive isolation follows and the populations begin to behave as different species. Various studies have examined patterns of assortative mating among species and sometimes populations, but few have examined variation in directional preferences, especially among populations of the same species. We investi- gated mate choice behavior in two populations of Labeotropheus fueUeborni, a Lake Malawi endemic. We test whether mating preferences between populations are based on the same traits and in the same direction as preferences within populations. We examine the potential contributions of two classes of trait, color patterns and behaviors, to reproductive isolation. When females chose between either two males of their own population, or two from another, female preferences were generally similar （for the female population） across the two contexts. Mate choice patterns differed between （female） populations for a measure of color, but only modestly for male behavior. In a separate experiment we simultaneously offered females a male of their own population and a male from a different population. In these trials, females consistently preferred males from their own population, which were also the males that displayed more frequently than their opponents, but not necessarily those with color traits suggested to be most attractive in the previous experiment. Thus directional preferences for chroma and related aspects of color may be important when females are presented with males of otherwise similar phenotypes, but may play little role in mediating assortative mating among populations with substantially different color patterns. A preference for male behavior could play some role in speciation if males preferentially court same-population females, as we have observed for the populations

关键词： Haplochromine cichlid Sexual selection Speciation Color Labeotropheus

Volcano video data characterized and classified using computer vision and machine learning algorithms

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Geoscience Frontiers 2020年第5期11卷 1789-1803页

作者： Alex j.C.Witsil jeffrey B.j.hnson Department of Geosciences Boise State UniversityBoiseIDUSA

Video cameras are common at volcano observatories,but their utility is often limited during periods of crisis due to the large data volume from continuous acquisition and time requirements for manual *** cameras to serve as effective monitoring tools,video frames must be synthesized into relevant time series signals and further analyzed to classify and characterize observable *** this study,we use computer vision and machine learning algorithms to identify periods of volcanic activity and quantify plume rise velocities from video *** were collected at Villarrica Volcano,Chile from two visible band cameras located^17 km from the vent that recorded at 0.1 and 30 frames per second between February and April *** these two months,Villarrica exhibited a diverse range of eruptive activity,including a paroxysmal eruption on 3 *** to and after the eruption,activity included nighttime incandescence,dark and light emissions,inactivity,and periods of cloud *** quantify the color and spatial extent of plume emissions using a blob detection algorithm,whose outputs are fed into a trained artificial neural network that categorizes the observable activity into five *** shifts from primarily nighttime incandescence to ash emissions following the 3 March paroxysm,which likely relates to the reemergence of the buried lava *** periods exhibiting plume emissions are further analyzed using a row and column proj.ction algorithm that identifies plume onsets and calculates apparent plume horizontal and vertical rise *** onsets are episodic,occurring with an average period of^50 s and suggests a puffing style of degassing,which is commonly observed at ***,the lack of clear acoustic transients in the accompanying infrasound record suggests puffing may be controlled by atmospheric effects rather than a degassing regime at the *** presented here offer a generalized toolset for volcano monito

关键词： Volcano monitoring Plume exit velocity Volcano webcam Image processing Machine learning Villarrica

Female and male visually based mate preferences are consistent with reproductive isolation between populations of the Lake Malawi endemic Labeotropheus fuelleborni

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Current Zoology 2010年第1期56卷 65-72页

作者： Michael j.PAUERS Timothy j.EHLINGER jeffrey S.McKINNON Department of Biological Sciences The University of Wisconsin-Milwaukee Division of Natural and Health Sciences Carroll University Department of Biology East Carolina University

Sexual selection via female mate choice is thought to have played a key role in the speciation ofhaplochromine cichlids, but a dominant role for visual signals in such processes has lately been called into question. In addition, the possible role of male mating preferences in haplochromine speciation has been little studied. We studied patterns of both female and male mate choice, based exclusively on visual signals, in order to evaluate potential reproductive isolation between two populations of the Lake Malawi haplochromine Labeotropheus fuelleborni. In the first experiment, females were allowed to choose between two males, one from the same population and the other allopatric with respect to the female. Females in this experiment responded more frequently to males from their own population. Similarly, the males in these trials displayed more frequently when presented with females of their own population. In the second experiment, a female was allowed to choose between two males, either both from her own population or both allopatric. In these trials, both males and females from the Katale population interacted significantly more frequently in settings in which all three individuals were from the same population （＂same-population trios＂）, and those from the Chipoka population showed a similar trend. Thus, patterns in both male and female courtship behavior suggest that visual signals contribute to at least incipient reproductive isolation between populations of L. fuelleborni [Current Zoology 56 （ 1 ）： 65-72 2010].

关键词： Cichlid Mate choice Reproductive isolation Sexual selection Speciation

High Oxygen Nanocomposite Barrier Films Based on Xylan and Nanocrystalline Cellulose

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Nano-Micro Letters 2010年第4期2卷 235-241页

作者： Amit Saxena Thomas j.Elder jeffrey Kenvin Arthur j.Ragauskas School of Chemistry and Biochemistry Georgia Institute of Technology USDA-Forest Service Southern Research Station Micromeritics Instrument Corporation

The goal of this work is to produce nanocomposite film with low oxygen permeability by casting an aqueous solution containing xylan,sorbitol and nanocrystalline *** morphology of the resulting nanocomposite films was examined by scanning electron microscopy and atomic force microscopy which showed that control films containing xylan and sorbitol had a more open structure as compared to xylan-sorbitol films containing sulfonated nanocrystalline *** average pore diameter,bulk density,porosity and tortuosity factor measurements of control xylan films and nanocomposite xylan films were examined by mercury intrusion porosimetry *** films reinforced with nanocrystalline cellulose were denser and exhibited higher tortuosity factor than the control xylan *** xylan films had average pore diameter,bulk density,porosity and tortuosity factor of 0.1730 μm,0.6165 g/ml,53.0161% and 1.258,respectively as compared to xylan films reinforced with 50% nanocrystalline cellulose with average pore diameter of 0.0581 μm,bulk density of 1.1513 g/ml,porosity of 22.8906% and tortuosity factor of *** transmission rate tests demonstrated that films prepared with xylan,sorbitol and 5%,10%,25% and 50% sulfonated nanocrystalline cellulose exhibited a significantly reduced oxygen permeability of 1.1387,1.0933,0.8986 and 0.1799 cm^3×μm/m^2×d×k Pa respectively with respect to films prepared solely from xylan and sorbitol with a oxygen permeability of 189.1665 cm^3×μm/m^2×d×k *** properties suggested these nanocomposite films have promising barrier properties.

关键词： Nanocomposites Xylan Nanocrystalline cellulose Oxygen barrier

Back to the drawing board:Overview of the next generation of combination therapy for inflammatory bowel disease

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World j.urnal of Gastroenterology 2024年第25期30卷 3182-3184页

作者： jeffrey A Lowell Michael j.Farber Keith Sultan Department of Medicine Zucker School of Medicine at HofstraNorth Shore University Hospital-Long Island Jewish Medical CenterManhassetNY 11030United States Preclinical Studies New York Institute of Technology College of Osteopathic MedicineGlen HeadNY 11545United States Division of Gastroenterology Northwell HealthNorth Shore University Hospital and Long Island Jewish Medical CenterGreat NeckNY 10021United States

Inflammatory bowel disease(IBD)is entering a potentially new era of combined *** et al provide an insightful review of the current state of combination therapy,with a focus on the use of a combined biologic and immunomodulator,as well as emerging data on the future potential of dual-biologic therapy(DBT).While current evidence for DBT is limited,encouraging safety profiles and ongoing trials suggest a brighter future for this *** importance of controlled trials should be stressed in establishing new treatment *** prospective randomized trials of DBT and perhaps future combinations of biologics and small molecule therapies will hopefully guide the next generation of IBD care.

关键词： Inflammatory bowel disease Biologics Immunomodulators Dual-therapy Combination therapy

Trait plasticity, not values, best corresponds with woodland plant success in novel and manipulated habitats

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j.urnal of Plant Ecology 2013年第3期6卷 201-210页

作者： Robert j.Warren II jeffrey K.Lake Department of Biology SUNY Buffalo State1300 Elmwood AvenueBuffaloNY 14222USA Department of Biology Adrian CollegeAdrianMI49221USA

Aims The clustering of plants with similar leaf traits along environmental gradients may arise from adaptation as well as acclimation to het-erogeneous habitat *** the forces that shape plant leaf traits requires both linking variation in trait morphology with abiotic gradients and linking that trait variation with plant per-formance under varying abiotic *** the spectrum of plant types,shade-tolerant evergreen herbs are relatively low in trait plasticity,compared to deciduous and sun-adapted *** plants employ stress-tolerant strategies for survival,which coincide with relatively static trait morphologies,slow growth and hence a lower ability to adj.st to changing environmental *** We investigate how the survival of two ecologically similar under-story evergreen species,Asarum arifolium and Hepatica nobilis,cor-responds with variation in six commonly measured functional traits(leaf area,specific leaf area,plant height,leaf number,leaf length and shoot mass)along natural and experimental abiotic *** examine temporal(the period 2007-9)and spatial(100 km)variations in these traits after(i)translocating 576 plants across a span from the southerm Appalachian Mountains in NC,USA,to the Piedmont,GA,USA,which includes north-and south-facing slope habitats and(ii)the experimental manipulation of diffuse light and soil *** findings We find that when translocated into a novel habitats,with novel environmental conditions that often are more extreme than the source habitat,both species appear capable of considerable mor-phological acclimation and generally converge to similar trait *** nobilis does not exhibit mean trait values particu-larly different from those of ***,but it demonstrates much greater phenotypic *** results indicate that relatively conservative plant species nonetheless acclimate and survive across heterogeneous environmental conditions.

关键词： Functional traits Asarum arifolium Hepatica nobilis niche specific leaf area understory