78 research outputs found

    Computer-aided instruction in dendrology: Preparation for distance learning

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    Many state legislatures are increasing public access to higher education by establishing more two-year institutions with lower tuition and fees than four-year institutions. This will likely increase the number of students enrolling in two-year institutions and later transferring to a four-year institutions. Transfer students presently comprise more than 30% of the University of Arkansas at Monticello\u27s (UAM) undergraduate forestry majors. These students arrive commonly deficient in six required freshman and sophomore forestry courses and facing four years at UAM to complete their baccalaureate degree. Prospective transfer students need access to freshman- and sophomore-level forestry courses. Forestry majors need tutorials aiding the development of skills and knowledge in plant morphology, identification, nomenclature and silvics. At UAM, experiences to a broader range of learning styles than traditional instruction alone. When combined with distance learning technologies, this approach can potentially reach prospective transfer students. Resolution of course deficiencies reduces problems for transfer students and academic advisors, and homogenizes levels of preparedness leading to higher quality instruction, student understanding and academic success. This paper introduces a series of PC-based tutorials and a format for electronic discussion groups in dendrology intended as part of a package for both resident and distant students. The user friendly tutorials provide easy access to approximately 120 species of native and exotic woody trees, shrubs and vines of the upper Coastal Plain of the Western Gulf Region. The self examination segment of the software allows students to pretest their skill and knowledge in the morphology, identification, and nomenclature of forest species as part of their preparation for actual examinations. The electronic discussion groups helps students learn from each other while catering to diverse learning styles and study schedules. This approach to dendrology is nontraditional and appeals to students either literate or illiterate in computer usage without reduced participation in traditional classroom experiences

    Genetic Family and Stock Type Influence Simulated Loblolly Pine Yields from Wet Sites

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    Planting adapted families or a bulked seedlot of bare-root and container-grown-seedlings of loblolly pine (Pinus taeda L) were contrasted as cost effective alternatives for regenerating Arkansas\u27 wet sites. Survival data from two wet sites were used to simulate 15 years of growth. Containerized seedlings provided 17% greater survival than bare-root seedlings, but yielded a lower present net worth than bare-root seedlings. Planting families adapted to excessive moisture provided 7% greater survival and yielded a greater present net worth than planting a bulked seedlot consisting of adapted and poorly adapted families

    Microhabitat conditions influence mesohabitat associations and distribution of larval salamanders in headwater streams

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    Distribution patterns of stream biota are the result of complex interactions between individuals and their surrounding environment. Determining the spatial scale by which an organism is most influenced is paramount to understanding distribution patterns. Using a multi-scale approach, we investigated factors influencing habitat associations of larval Ambystoma barbouri (streamside salamander) and Eurycea cirrigera (southern two-lined salamander) in three Kentucky headwater streams. We used likelihood ratio G tests to identify associations between species and mesohabitat (i.e., runs, riffles, and pools), and we used microhabitat variables to predict the presence and abundance of salamanders via a priori multiple regression modeling. Ambystoma barbouri presence and abundance were influenced by conditions at micro-scales, which in turn dictated mesohabitat associations. Eurycea cirrigera were also influenced by microhabitat variables, but displayed associations to A. barbouri presence in late spring. Associations of larval salamanders to mesohabitat and microhabitat parameters shifted from early to late spring, likely in response to changes in developmental stage. The multi-scale approach of our study improved our understanding of complex relationships between larval salamanders and their surrounding environment in headwaters, and underscored the importance of (1) research investigating multiple spatial and temporal scales and (2) heterogeneous in-stream habitat to headwater biota

    Survival and Growth Two Years After Control of Herbaceous Competitors in Newly Planted Seedlings of Loblolly Pine

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    Early or late over-the-top applications of herbicides were used to control herbaceous competition in machine planted loblolly pine (Pinus taeda L) seedlings at two locations in a pasture near Alleene and hand planted seedlings on a bedded site near Fouke. Sites were selected for diverse competitors. None of the treatments controlled weeds for the entire growing season. Only glyphosate + sulfometuron methyl produced seedling survival and growth below the check plots. The best over-the-top treatments were sulfometuron methyl alone or sulfometuron methyl + hexazinone

    Control of Herbaceous Competitors in Progeny Tests Using Container-grown Seedlings

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    Container-grown and May-planted seedlings of loblolly and shortleaf pines were treated with herbicides for control of herbaceous competitors. Weed control and seedling growth were evaluated. Competitor control was good for all treatments. Survival and growth of pines differed by species and herbicide treatment. The best treatment for both species included covering seedlings and spraying competitors with glyphosate. Both species showed decreased survival and growth when treated with medium and high rates of hexazinone + sulfometuron methyl

    Evaluating Hunting Success of Pen-Reared and Wild Northern Bobwhite in a Reclaimed Kentucky Mineland

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    Northern bobwhites (Colinus virginianus) have experienced severe population declines across their distribution. In order to address population declines and to continue providing hunting opportunities, multi-state efforts have been undertaken to stabilize and restore bobwhite populations. Ongoing efforts using the National Bobwhite Conservation Initiative’s quail focus area approach have so far demonstrated success throughout Kentucky. However, population increases in the Peabody Bobwhite Focal Area, in western Kentucky, have not been correlated to increases in perceived hunter success. Consequently, some sportsmen question the effectiveness of focal area conservation. In response to hunter concerns, we tested dog hunting ability with wild and pen-reared bobwhites. We also measured evasive behaviors of wild bobwhite using radiotelemetry. During the 2013–2014 and 2014–2015 hunting seasons we conducted 114 dog trials. Dogs detected bobwhite during 46 of 59 (78.0%) pen-reared trials and 16 of 55 (29.1%) wild bird trials. When dogs did not detect wild quail, birds ran away 64.1% of the time and remained motionless 20.5% of the time. Using an information-theoretic approach, we determined that bird type (wild vs. pen-reared) had a significant effect on bird detection, with dogs 8.62 times more likely to detect pen-reared birds than wild birds. We recommend that hunters be informed about differences in dog detection rates between pen-reared and wild bobwhite so that public support needed for wild bobwhite restoration can persist

    Effects of Broad-Scale Conservation on Northern Bobwhite Populations in Agricultural Landscapes

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    Private land initiatives such as the Conservation Reserve Enhancement Program (CREP) are avenues for broad-scale northern Bobwhite (Colinus virginianus) conservation. The CREP in Kentucky established 40,468 ha of native prairie grasses and riparian corridors in the Green River Basin. Northern bobwhite responses to similar conservation measures at local scales (i.e., the site of implementation) have been positive; however, the geographic extent of the influence of private land initiatives on populations is less understood. Our objectives were to investigate landscape-scale effects of CREP on northern bobwhite populations. Using a stratified random sampling design, 254 roadside point counts were performed over 5 years throughout the Green River Basin along a gradient of landscape-scale CREP density. Local-scale (500 m radius) CREP density was held constant at monitoring points. We analyzed data using an openpopulation distance sampling model that included estimators of appropriate landscape scale and strength of density dependence. Population response to the CREP was positive and outweighed conservation footprint. Our results suggest that broad-scale conservation can influence wildlife populations outside of targeted areas. Concurrently, because the majority of land in the Eastern U.S. is privately owned, private land conservation initiatives present an effective strategy for promoting wildlife population recovery across large areas. Our future directions with this research include improving model estimators, determining mechanisms behind landscape-scale effects of CREP, and determining the influence of the spatial arrangement of landscape features on local populations

    Effects of Midrotation Intensive Silviculture on Forest Soils in East Texas: First-Year Results

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    Intensive forest management is becoming increasingly common in east Texas. Included in intensive management are such practices as mid-rotation fertilization, prescribed fire, and herbicide application. There is insufficient information about the effects of these treatments on soil physical, chemical, and biological properties when applied at mid-rotation. The objectives of this research are to evaluate the effects of these treatments on soil physical properties including organic matter content and bulk density; chemical properties including soil nitrogen and phosphorus; and on populations of resident earthworms. Five replications were installed in each of two loblolly pine (Pinus taeda L.) plantations aged 15 and 17. Both were thinned in 1998. Accord SP and Chopper emulsion were ground applied in the fall of 1999. The prescribed burn treatment occurred the following spring. Fertilizer was applied one to two weeks after completion of the burn to supply 224 kilograms per hectare of N and 28 kilograms per hectare of P. First-year results are presented

    The soluble pattern recognition receptor PTX3 links humoral innate and adaptive immune responses by helping marginal zone B cells

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    © 2016 Chorny et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 3.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/3.0/).Pentraxin 3 (PTX3) is a fluid-phase pattern recognition receptor of the humoral innate immune system with ancestral antibody-like properties but unknown antibody-inducing function. In this study, we found binding of PTX3 to splenic marginal zone (MZ) B cells, an innate-like subset of antibody-producing lymphocytes strategically positioned at the interface between the circulation and the adaptive immune system. PTX3 was released by a subset of neutrophils that surrounded the splenic MZ and expressed an immune activation-related gene signature distinct from that of circulating neutrophils. Binding of PTX3 promoted homeostatic production of IgM and class-switched IgG antibodies to microbial capsular polysaccharides, which decreased in PTX3-deficient mice and humans. In addition, PTX3 increased IgM and IgG production after infection with blood-borne encapsulated bacteria or immunization with bacterial carbohydrates. This immunogenic effect stemmed from the activation of MZ B cells through a neutrophil-regulated pathway that elicited class switching and plasmablast expansion via a combination of T cell-independent and T cell-dependent signals. Thus, PTX3 may bridge the humoral arms of the innate and adaptive immune systems by serving as an endogenous adjuvant for MZ B cells. This property could be harnessed to develop more effective vaccines against encapsulated pathogens.This study was supported by European Advanced grant ERC-2011-ADG-20110310, Ministerio de Ciencia e Innovación grant SAF2011-25241, and Marie Curie reintegration grant PIRG-08-GA-2010-276928 to A. Cerutti; Sara Borrell post-doctoral fellowships to A. Chorny; and US National Institutes of Health grants R01 AI57653, U01 AI95613, P01 AI61093, and U19 096187 to A. Cerutti. C. Cunha and A. Carvalho were funded by grants from Fundação para a Ciência e Tecnologia, co-funded by Programa Operacional Regional do Norte (ON.2—O Novo Norte)., and from the Quadro de Referência Estratégico Nacional (SFRH/BPD/96176/2013 to C. Cunha and grant IF/00735/2014 to A. Carvalho) through the Fundo Europeu de Desenvolvimento Regional and Projeto Estratégico (LA 26 – 2013–2014; PEst-C/SAU/LA0026/2013). The financial support of the European Commission (FP7-HEALTH-2011-ADITEC-No.280873 and ERC-PHII-669415) to A. Mantovani is gratefully acknowledged.info:eu-repo/semantics/publishedVersio
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