2,377 research outputs found
Stand- and Landscape-level Roost Selection by Forest Bats in the Ouachita Mountains
The purpose of this study was to determine roosting habitat preferences by forest bats and to create landscape-level models to determine characteristics of the landscape that were associated with roosting locations. I located 428 roosts from 162 individual bats of 6 species. Using Euclidean distance statistics and the individual bat as the experimental unit, I determined preference and avoidance for 13 habitat types in the Ouachita Mountains of central Arkansas. I also used logistic regression to create scale-dependent models that differentiated habitat classes, topography, and landscape patch metrics of roost locations from random locations. In general, most bat species preferred to roost in stands that had been partially harvested and contained few midstory trees. The most preferred habitats were partially harvested mixed pine-hardwood stands and stands ≥99 years old. Although highly available, second-growth mixed pine-hardwood stands that were 50--99 years old were only preferred by 1 bat species. Forest habitat classes were included more often that topographic or patch-configuration metrics in landscape models. Fine-scale models were a better fit than broad-scale models for most species. Most models included habitat classes of partially harvested or thinned forest that retained mature overstory trees. For all species combined, bats were more likely to roost in close proximity to water sources and in areas that contained less dense or young forest than random locations.Department of Natural Resource Ecology and Managemen
Temporal changes in fruit production between recurrent prescribed burns in pine woodlands of the Ouachita Mountains
The use of prescribed fire is integral to the restoration of open woodlands and savannas, including shortleaf pine (Pinus echinata) woodlands in the Ouachita Mountains of Oklahoma and Arkansas. Fire offers many potential benefits to numerous wildlife; however, short-term implications for understory fruit production are not fully understood, especially in stands subjected to frequent, recurrent burns. We examined the effects of dormant season prescribed burns on woody fruit production (kg ha−1) and fruit producing vegetative cover in the understory of restored pine woodlands. We inventoried 32 stands during four temporal periods after dormant season prescribed fires: 1, 2, 3, and 5 growing seasons post-burn. We counted fruit (\u3c2 m above the ground) throughout the summer and visually estimated vegetative cover of fruit producing plants. Fruit production was greatest in the 3rd year (18.2 kg ha−1), followed by 5th (10.9 kg ha−1) and 2nd (9.8 kg ha−1) years after burns. Overall, 87% of total production consisted of three genera: American beautyberry (Callicarpa americana [38%]), Vitis spp. (summer grapes [Vitis aestivalis; 11%] and muscadine grape [V. rotundifolia; 10%]), and Rubus spp. (blackberry [20%] and dewberry [R. flagellaris; 8%]). Production was recorded in 13 of the 14 fruit producing species present during the 5th year post-burn, indicating that production diversity increased over time. Percent cover and species richness (26 taxa) of fruit producing taxa were greatest in the 3rd year post-burn. Taxa such as poison ivy (Toxicodendron radicans) and sumac (Rhus spp.) comprised a sizable percent of coverage (\u3e7% each), but this did not translate into substantial fruit production. American beautyberry and summer grape had both substantial coverage and production. Results suggest that burning on a 3-year rotation maximizes and prolongs fruit production; however, occasional burning on a 5-year rotation will promote a higher diversity of woody mast-producing understory species
Increased Oxygen Recovery from Sabatier Systems Using Plasma Pyrolysis Technology and Metal Hydride Separation
State-of-the-art life support carbon dioxide (CO2) reduction technology is based on the Sabatier reaction where less than 50% of the oxygen required for the crew is recovered from metabolic CO2. The reaction produces water as the primary product and methane as a byproduct. Oxygen recovery is constrained by the limited availability of reactant hydrogen. This is further exacerbated when Sabatier methane (CH4) is vented as a waste product resulting in a continuous loss of reactant hydrogen. Post-processing methane with the Plasma Pyrolysis Assembly (PPA) to recover hydrogen has the potential to dramatically increase oxygen recovery and thus drastically reduce the logistical challenges associated with oxygen resupply. The PPA decomposes methane into predominantly hydrogen and acetylene. Due to the highly unstable nature of acetylene, a separation system is necessary to purify hydrogen before it is recycled back to the Sabatier reactor. Testing and evaluation of a full-scale Third Generation PPA is reported and investigations into metal hydride hydrogen separation technology is discussed
Systematic Renormalization in Hamiltonian Light-Front Field Theory: The Massive Generalization
Hamiltonian light-front field theory can be used to solve for hadron states
in QCD. To this end, a method has been developed for systematic renormalization
of Hamiltonian light-front field theories, with the hope of applying the method
to QCD. It assumed massless particles, so its immediate application to QCD is
limited to gluon states or states where quark masses can be neglected. This
paper builds on the previous work by including particle masses
non-perturbatively, which is necessary for a full treatment of QCD. We show
that several subtle new issues are encountered when including masses
non-perturbatively. The method with masses is algebraically and conceptually
more difficult; however, we focus on how the methods differ. We demonstrate the
method using massive phi^3 theory in 5+1 dimensions, which has important
similarities to QCD.Comment: 7 pages, 2 figures. Corrected error in Eq. (11), v3: Added extra
disclaimer after Eq. (2), and some clarification at end of Sec. 3.3. Final
published versio
Repair of anomalous origin of the left coronary artery in the infant and small child
Anomalous origin of the left coronary artery from the pulmonary artery is associated with myocardial infarction, left ventricular dysfunction, mitral valve dysfunction and, occasionally, intracardiac congenital abnormalities. A technique that utilizes a flap of the anterior wall of the pulmonary artery to serve as a neocoronary artery to direct aortic flow from a created aortopulinonary window to the pulmonary artery orifice of the anomalous left coronary artery was used in five patients aged 2.5 months to 4.75 years. Two patients were less than 4 months of age at operation. There was one death 2 days after operation and one late death. The two youngest patients required mitral valve replacement. Two of the three surviving patients are well at follow-up at 7 to 44 months. One patient has been lost to follow-up study. One patient had postoperative catheterization which showed an intact repair. The pulmonary artery neocor-onary procedure is applicable to infants and small patients with anomalous origin of the left coronary artery from the pulmonary artery
The Vehicle, 1969, Vol. 11 no. 2
Vol. 11, No. 2
Table of Contents
Short Story: The TripCharles Whitepage 4
PhotoDale Huberpage 5
A NightRoger Zulaufpage 6
Sixteen-year-old Students...NBpage 6
LostJim Biropage 6
The AmateurRoger Zulaufpage 7
ManRoger Zulaufpage 7
My CamelotRonald Garnerpage 7
The Rose and the BriarKenneth L. Folkertspage 9
Who Am I?Frank McKennedypage 10
PhotoDale Huberpage 11
Mr. Samuel ClemensLarry A. Millerpage 11
Lock OutAra Childspage 12
Excuse MeRoger Zulaufpage 12
On Shadows from a Candle \u2767Michael G. McKeepage 12
beginning of an endCaryl Dagropage 12
DrawingMADpage 13
We Ain\u27t Un HurJames Birchlerpage 13
Genesis II, 18 \u2767Michael G. McKeepage 13
Short Story: A Patent Leather PaleEleanor Aikenpage 14
hungry childRoger Zulaufpage 15
DrawingRoger Zulaufpage 15
PhotoRoger Digglepage 16
Do You Like The Rain?Linda Boltmanpage 17
Seasons ChangePerry J. Carterpage 17
PhotoDale Huberpage 19
Whistling TreesPam McKinneypage 19
PostscriptThomas W. Reapage 20
PhotoDale Huberpage 20https://thekeep.eiu.edu/vehicle/1020/thumbnail.jp
The Vehicle, 1969, Vol. 11 no. 2
Vol. 11, No. 2
Table of Contents
Short Story: The TripCharles Whitepage 4
PhotoDale Huberpage 5
A NightRoger Zulaufpage 6
Sixteen-year-old Students...NBpage 6
LostJim Biropage 6
The AmateurRoger Zulaufpage 7
ManRoger Zulaufpage 7
My CamelotRonald Garnerpage 7
The Rose and the BriarKenneth L. Folkertspage 9
Who Am I?Frank McKennedypage 10
PhotoDale Huberpage 11
Mr. Samuel ClemensLarry A. Millerpage 11
Lock OutAra Childspage 12
Excuse MeRoger Zulaufpage 12
On Shadows from a Candle \u2767Michael G. McKeepage 12
beginning of an endCaryl Dagropage 12
DrawingMADpage 13
We Ain\u27t Un HurJames Birchlerpage 13
Genesis II, 18 \u2767Michael G. McKeepage 13
Short Story: A Patent Leather PaleEleanor Aikenpage 14
hungry childRoger Zulaufpage 15
DrawingRoger Zulaufpage 15
PhotoRoger Digglepage 16
Do You Like The Rain?Linda Boltmanpage 17
Seasons ChangePerry J. Carterpage 17
PhotoDale Huberpage 19
Whistling TreesPam McKinneypage 19
PostscriptThomas W. Reapage 20
PhotoDale Huberpage 20https://thekeep.eiu.edu/vehicle/1020/thumbnail.jp
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DNA methylation-based classification of central nervous system tumours.
Accurate pathological diagnosis is crucial for optimal management of patients with cancer. For the approximately 100 known tumour types of the central nervous system, standardization of the diagnostic process has been shown to be particularly challenging-with substantial inter-observer variability in the histopathological diagnosis of many tumour types. Here we present a comprehensive approach for the DNA methylation-based classification of central nervous system tumours across all entities and age groups, and demonstrate its application in a routine diagnostic setting. We show that the availability of this method may have a substantial impact on diagnostic precision compared to standard methods, resulting in a change of diagnosis in up to 12% of prospective cases. For broader accessibility, we have designed a free online classifier tool, the use of which does not require any additional onsite data processing. Our results provide a blueprint for the generation of machine-learning-based tumour classifiers across other cancer entities, with the potential to fundamentally transform tumour pathology
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