533 research outputs found
Population Status and Trends of Northern Bobwhite (Colinus virginianus) in Ohio: 1984- 2004
Author Institution: Terrestrial Wildlife Ecology Laboratory, School of Environment and Natural Resources, The Ohio State UniversityWe assessed the status and trends of northern bobwhite (Colinus virginianus) populations in Ohio from 1984-2004 (21
years). Bobwhite abundance indices were obtained from surveys conducted on secondary roads. The number of roads surveyed per year ranged from 69 to 209 (with 12 stops each). We used Poisson regression with generalized estimating equations and a Generalized Additive Model to analyze bobwhite population trends. Bobwhite populations in Ohio declined 9.3% / year (95% CI=7.3%-11.2%). Overall, populations declined 76% (95% CI=68-82%) over the 21-year period. We also compared annual trends during the same period among 10 weather regions in the state. At least six weather regions showed declining population trends, but analyses for the remaining four regions were inconclusive. We mapped the distribution and abundance of bobwhites in Ohio using abundance indices from surveys conducted during 1985, 1992, and 2002. These maps revealed that the bobwhite range contracted as populations declined during 1984-2004. The current core area of bobwhite abundance is located in Southwestern Ohio, where 16 counties are open for hunting. However, bobwhite distribution shifted eastward within Southwestern Ohio during 1984-2004. Adjacent counties that are currently closed to hunting lie mostly outside the highest abundance zone. We recommend bobwhite population surveys of high resolution on counties open to hunting, as well as surrounding counties where hunting has recently been closed. However, lower resolution efforts, such as site occupancy surveys, should be conducted outside those areas to detect range expansio
The Bedrock Geology of the Waterbury and Thomaston Quadrangles
Guidebook for field trips in Connecticut: New England Intercollegiate Geological Conference 60th annual meeting, Yale University, New Haven, Connecticut, October 25-27, 1968: Trip D-
Comparison of Some Exact and Perturbative Results for a Supersymmetric SU() Gauge Theory
We consider vectorial, asymptotically free supersymmetric
SU() gauge theories with copies of massless chiral super fields in
various representations and study how perturbative predictions for the lower
boundary of the infrared conformal phase, as a function of , compare with
exact results. We make use of two-loop and three-loop calculations of the beta
function and anomalous dimension of the quadratic chiral super field operator
product for this purpose. The specific chiral superfield contents that we
consider are copies of (i) , (ii) , (iii) ,
and (iv) , where , , , and denote,
respectively, the fundamental, adjoint, and symmetric and antisymmetric rank-2
tensor representations. We find that perturbative results slightly overestimate
the value of relative to the respective exact results for these
representations, i.e., slightly underestimate the interval in for which
the theory has infrared conformal behavior. Our results provide a measure of
how closely perturbative calculations reproduce exact results for these
theories.Comment: 16 pages, 3 figure
Effects of Hikers and Boats on Tule Elk Behavior in a National Park Wilderness Area
Human disturbance of wildlife may cause disruption of normal feeding, resting, reproduction, or care for juveniles. Such disturbance may be particularly undesirable in federally managed wilderness areas designed to minimize human influences on natural resources. We recorded tule elk (Cervus elephus nannodes) responses (standing, walking away, running) to off-trail hikers, off-shore boats, and other natural and anthropogenic factors in Point Reyes National Seashore in northern California during 2002 to 2008. Most disturbance behaviors were related to other elk exhibiting rutting behaviors, but off-trail hikers still explained a 100% increase and off-shore boats a 15% increase in baseline disturbance behaviors by elk. However, off-trail hikers and boats did not cause elk to enter or leave the study area during the sample periods. Elk were more prone to human disturbance when herd sizes wereand, to a lesser extent, offshore boats appear to disturb natural tule elk behavior, but the physiological or population-level effects of this disturbance are unknown. Our quantitative results may help park managers minimize or mitigate human–elk interactions in wilderness areas
Fatigue Testing a Mechanized Percussion Well Drilling System for Water Access in Western Africa
The Mechanized Percussion Well Drilling (MPWD) Collaboratory project seeks to design a simple mechanized well drilling system for drilling shallow water wells in Western Africa. Our client, Open Door Development (ODD), seeks to make water accessible to all in the region, but has had difficulty drilling through hard soil layers. To combat this problem, the MPWD team has worked closely with Mr. Joseph Longenecker to develop a mechanized percussion well drilling rig that is capable of drilling through these harder layers. Currently, the MPWD team is seeking to provide recommendations to improve the lifetime of our client’s new, fully mechanized rig design. This year, our team’s work has been focused specifically on analyzing the lifetime of the rig’s driveline chains and also on its frame. For the driveline chains, the team will be conducting fatigue testing on a model of the driveline system to determine which type of chain should be used on the rig. To determine the lifetime of the frame, the team will be performing a series of static, buckling, and fatigue finite element analyses on the rig’s frame. The most recent accomplishments of the MPWD team have nearly proved that their design for the loading application will be feasible for use on the actual testing rig and that multiple studies of finite element analysis can be performed to simulate the different rig frame loading scenarios.https://mosaic.messiah.edu/engr2021/1019/thumbnail.jp
An evolutionary construction facility for Space Station Freedom
Viewgraphs and discussion on an evolutionary construction facility for Space Station Freedom are presented. Space Station Freedom (SSF) will support permanent human presence in space and has the potential to enable scientific and exploratory endeavors unequalled in history. With larger and more ambitious spacecraft being developed, it will serve as a site for construction, checkout, and deployment. A facility attached to SSF is required to develop and demonstrate the techniques that will enable on-orbit construction of future large spacecraft. Examples of attached scientific experiments that currently envision in-space construction and that are discussed are: Solar X-ray Pinhole Occulter Facility, Astromag, and X-ray Large Array. Examples of large assemblable spacecraft which are discussed are: Large Deployable Reflector (LDR), Geostationary Platforms, and interplanetary vehicles
Air Exchange Rate in a Horse Trailer During Road Transport
Horses traveling by road commonly experience heat stress conditions and poor air quality, which may be caused by insufficient ventilation; however, there are few estimates of air exchange in a horse trailer during transport. Air exchange rate was measured at ten locations within a four-horse trailer (internal volume 18.5 m3) using tracer gas decay measurement to assess the adequacy of ventilation. Three vehicle speeds (13, 48, and 97 km h-1) and three window configurations (all windows and roof vents closed, all windows open, all windows open and roof vents open forward) were tested with and without animals present in the trailer. External air temperature ranged from 22.3°C to 28.3°C with an average of 25.3°C, and internal air temperature ranged from 29.9°C to 34.8°C with an average of 31.3°C with animals present. Air exchange rate increased with vehicle speed and open window and vent area. The average air exchange rate over all vehicle speeds and ventilation configurations was 0.52 min-1 with animals present and 0.76 min-1 without animals. Without animals present, the maximum mean exchange rate was 1.42 min-1 at 97 km h-1 at the rear left window with all windows and vents open; the lowest mean exchange rate was 0.12 min-1 at 13 km h-1 with all windows and vents closed at the lower position of the rearmost stall divider. With animals present, the maximum air exchange rate observed was 0.84 min-1 with all windows and vents open and traveling at 97 km h-1. Ventilation in the trailer was not adequate when compared to recommendations for stabled horses for any combination of vehicle speed or ventilation configuration. Increasing open vent area, either by increasing the number and size of roof vents or the size of windows in the sidewall, would be the most cost-effective means of increasing air exchange in a horse trailer
Characterization of an electron conduit between bacteria and the extracellular environment
A number of species of Gram-negative bacteria can use insoluble minerals of Fe(III) and Mn(IV) as extracellular respiratory electron acceptors. In some species of Shewanella, deca-heme electron transfer proteins lie at the extracellular face of the outer membrane (OM), where they can interact with insoluble substrates. To reduce extracellular substrates, these redox proteins must be charged by the inner membrane/periplasmic electron transfer system. Here, we present a spectro-potentiometric characterization of a trans-OM icosa-heme complex, MtrCAB, and demonstrate its capacity to move electrons across a lipid bilayer after incorporation into proteoliposomes. We also show that a stable MtrAB subcomplex can assemble in the absence of MtrC; an MtrBC subcomplex is not assembled in the absence of MtrA; and MtrA is only associated to the membrane in cells when MtrB is present. We propose a model for the modular organization of the MtrCAB complex in which MtrC is an extracellular element that mediates electron transfer to extracellular substrates and MtrB is a trans-OM spanning ß-barrel protein that serves as a sheath, within which MtrA and MtrC exchange electrons. We have identified the MtrAB module in a range of bacterial phyla, suggesting that it is widely used in electron exchange with the extracellular environment
Rapid typing of Coxiella burnetii
Coxiella burnetii has the potential to cause serious disease and is highly prevalent in the environment. Despite this, epidemiological data are sparse and isolate collections are typically small, rare, and difficult to share among laboratories as this pathogen is governed by select agent rules and fastidious to culture. With the advent of whole genome sequencing, some of this knowledge gap has been overcome by the development of genotyping schemes, however many of these methods are cumbersome and not readily transferable between institutions. As comparisons of the few existing collections can dramatically increase our knowledge of the evolution and phylogeography of the species, we aimed to facilitate such comparisons by extracting SNP signatures from past genotyping efforts and then incorporated these signatures into assays that quickly and easily define genotypes and phylogenetic groups. We found 91 polymorphisms (SNPs and indels) among multispacer sequence typing (MST) loci and designed 14 SNP-based assays that could be used to type samples based on previously established phylogenetic groups. These assays are rapid, inexpensive, real-time PCR assays whose results are unambiguous. Data from these assays allowed us to assign 43 previously untyped isolates to established genotypes and genomic groups. Furthermore, genotyping results based on assays from the signatures provided here are easily transferred between institutions, readily interpreted phylogenetically and simple to adapt to new genotyping technologies
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