4,992 research outputs found
Lazarus ecology: Recovering the distribution and migratory patterns of the extinct Carolina parakeet.
The study of the ecology and natural history of species has traditionally ceased when a species goes extinct, despite the benefit to current and future generations of potential findings. We used the extinct Carolina parakeet as a case study to develop a framework investigating the distributional limits, subspecific variation, and migratory habits of this species as a means to recover important information about recently extinct species. We united historical accounts with museum collections to develop an exhaustive, comprehensive database of every known occurrence of this once iconic species. With these data, we combined species distribution models and ordinal niche comparisons to confront multiple conjectured hypotheses about the parakeet's ecology with empirical data on where and when this species occurred. Our results demonstrate that the Carolina parakeet's range was likely much smaller than previously believed, that the eastern and western subspecies occupied different climatic niches with broad geographical separation, and that the western subspecies was likely a seasonal migrant while the eastern subspecies was not. This study highlights the novelty and importance of collecting occurrence data from published observations on extinct species, providing a starting point for future investigations of the factors that drove the Carolina parakeet to extinction. Moreover, the recovery of lost autecological knowledge could benefit the conservation of other parrot species currently in decline and would be crucial to the success of potential de-extinction efforts for the Carolina parakeet
Trade-offs between conflicting animal welfare concerns and cow replacement strategy in out-wintering Scottish suckler herds
Since decoupling of the CAP, many Scottish suckler cow farms are facing financial difficulties. In response, many farmers are out-wintering extensively managed suckler cows to minimise production costs. These systems are of animal welfare concern. A range of trade-offs between animal welfare indicators and between animal welfare and farm profitability can be identified. A Dynamic Programming (DP) model was developed to study these trade-offs. Two herds were modelled assuming their feeding regimes were either low (LHERD) or high (HHERD). The objective of the DP was to maximise the expected net margin from a current cow and its successors over an infinite time horizon. Preliminary results showed that the rate of voluntary culling was higher in HHERD than in LHERD. Animals in HHERD had shorter life expectancy. The expected net present value was 58% lower in LHERD than HHERD (-£41.5 and -£24.3 respectively). These results suggest a heavier culling rate and shorter longevity for animals in HHERD that compromises animal welfare. Also HHERD had a greater implied stocking density than LHERD. This increase of the cows’ population may adversely affect the environment. The presented model provides some of the basic information required to explore some of the trade-offs between farm profit, animal welfare and the environment.Livestock Production/Industries, Beef cow, economics, dynamic programming, animal welfare,
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Beagle 2: Seeking the signatures of life on Mars
ESA's Beagle 2 lander will land on Mars to search for signatures of present and past life. A Gas Analysis Package (GAP) with a mass spectrometer, XRF, Mossbauer, stereo cameras, microscope, environmental sensors, rock corer/grinder, and a Mole attachment are on the lander
A Comparison of Adaptations via Either a Linear Periodization or an Undulating Periodization Model of Weight Training
BACKGROUND: Resistance training has been proven to have a positive impact on parameters such as muscular strength, hypertrophy and endurance. Periodization is a progressive mode of training that has been shown to illicit greater results than programs that stay consistent throughout. The two prime modes of periodization are linear (LP), which progresses from high volume/low intensity to low volume/high intensity, and undulating (UP) which follows an oscillating volume/intensity design. The purpose of this study was to compare the effects of a 12 week linear program to those from an undulating program on strength and body composition when both programs reflect the entire NSCA repetition continuum. METHODS: 10 resistance trained men were matched according to weight-relative strength and randomly assigned to either a linear (N=4, 21 ± 2.5 yrs, 69.08 ± 0.69in, 1178.13 ± 19.5 lbs, 16.9 ± 5.2 %BF) or undulating (N=6, 20 ± 1.7 yrs, 70.27 ± 2.13 in, 180.17 ± 23.98 lbs, 13.67 ± 2.94 %BF) periodization program. Subjects participated in 3 days per week of supervised total body resistance training with repetitions and intensities reflecting the entire NSCA repetition continuum. At 0, 4, 8 and 12-weeks, subjects were tested on body composition via dual energy x-ray absorptiometry, 1RM strength, muscular endurance, vertical jump and anaerobic capacity. Statistical analyses utilized a two-way ANOVA with repeated measures for all criterion variables (p ≤ 0.05). Data are presented as mean ± SD changes from baseline values. RESULTS: Significant main effects for time (p \u3c 0.05) were observed on bench press (LP: 15.03 ± 8.02 lb; UP: 26.10 ± 5.05 lb), leg press (LP:161.07 ± 14.10 lb ; UP: 164.03 ± 55.20 lb), and Wingate peak power (LP: 148.21 ± 78.05 W; UP: 143.22 ± 137.04 W). However, no significant interactions were observed between groups on any of these parameters. Also, no significant group or time effects for time or differences between groups were observed in the measures of percent body fat, lean muscle mass, or vertical jump. CONCLUSION: Both undulating and linear periodization models of resistance training that reflect the entire repetition continuum can bring forth highly significant changes in strength and peak anaerobic power. However, despite the fact that the undulating method resulted in a 43% greater increase in upper body strength, there is no significant difference in the magnitude of the training adaptations that stem from the two methods over 12 weeks
The Effects of Pre- and Post-Exercise Whey vs. Casein Protein Consumption on Body Composition and Performance Measures in Collegiate Female Athletes
Two of the most popular forms of protein on the market are whey and casein. Both proteins are derived from milk however the two differ concerning their absorption in the body. This difference between whey and casein proteins could affect the response seen in conjunction with training. PURPOSE: To investigate the potential effects of two types of protein ingestion in conjunction with a controlled resistance training program utilizing college female basketball players. METHODS: 16 NCAA Division III female basketball players were matched according to weight and double-blind randomly assigned to consume 24 grams whey protein (WP) (N = 8, 20 ± 1.9 years, 158 ± 27.3 cm, 66 ± 4.9 kg, 27 ± 4.9 %BF) or 24 grams casein protein (CP) (N = 8, 21 ± 2.8 years, 153 ± 2.9 cm, 68 ± 2.9 kg, 25 ± 5.7 %BF) pre- and post-exercise for eight weeks. Subjects participated in a supervised 4-day per week undulating periodized training program. At 0, 4, and 8 weeks, subjects underwent DEXA body composition analysis. At 0 and 8 weeks subjects underwent 1RM strength, muscle endurance, vertical jump, 5-10-5 and broad jump testing sessions. Data analysis using repeated measures ANOVA are presented as mean ± SD changes from baseline after 60 days. RESULTS: No significant group x time interaction effects were observed among groups in changes in any variable (p \u3e 0.05). A significant time effect was observed for body fat (WP: -2 ± 1.1 %BF; CP: -1 ± 1.6 %BF, p \u3c 0.001), lean mass (WP: 1.5 ± 1 kg; CP: 1.4 ± 1 kg, p \u3c 0.001), fat mass (WP: -1.3 ± 1.2 kg; CP: -0.6 ± 1.4 kg, p \u3c 0.001), leg press 1RM (WP: 88.7 ± 43.9 kg; CP: 90 ± 48.5 kg, p \u3c 0.001), bench press 1RM (WP: 7.5 ± 4.6 kg; CP: 4.3 ±4.5 kg, p = 0.01), vertical jump (WP: 1.6 ± 0.74 in; CP: 1.4 ± 3 in, p \u3c 0.001), 5-10-5 (WP: -0.3 ± 0.2 sec; CP: -0.09 ± 0.42 sec, p \u3c 0.001), and broad jump (WP: 4.1 ± 2.6 in; CP: 5.1 ± 2.8 in, p \u3c 0.001). CONCLUSION: The combination of a controlled undulating resistance training program with pre- and post-exercise protein supplementation is capable of inducing significant changes in performance and body composition. There does not appear to be a difference in the performance enhancing effects of whey versus casein proteins
Characterising encapsulated nuclear waste using cosmic-ray muon tomography
Tomographic imaging techniques using the Coulomb scattering of cosmic-ray
muons have been shown previously to successfully identify and characterise low-
and high-Z materials within an air matrix using a prototype scintillating-fibre
tracker system. Those studies were performed as the first in a series to assess
the feasibility of this technology and image reconstruction techniques in
characterising the potential high-Z contents of legacy nuclear waste containers
for the UK Nuclear Industry. The present work continues the feasibility study
and presents the first images reconstructed from experimental data collected
using this small-scale prototype system of low- and high-Z materials
encapsulated within a concrete-filled stainless-steel container. Clear
discrimination is observed between the thick steel casing, the concrete matrix
and the sample materials assayed. These reconstructed objects are presented and
discussed in detail alongside the implications for future industrial scenarios.Comment: 6 pages, 4 figure
The use of geoscience methods for aquatic forensic searches
There have been few publications on the forensic search of water and fewer still on the
use of geoforensic techniques when exploring aqueous environments. Here we consider
what the nature of the aqueous environment is, what the forensic target(s) may be,
update the geoforensic search assets we may use in light of these, and provide a search
strategy that includes multiple exploration assets. Some of the good practice involved in
terrestrial searches has not been applied to water to-date, water being seen as
homogenous and without the complexity of solid ground: this is incorrect and a full
desktop study prior to searching, with prioritized areas, is recommended. Much
experimental work on the decay of human remains is focused on terrestrial surface
deposition or burial, with less known about the nature of this target in water, something
which is expanded upon here, in order to deploy the most appropriate geoforensic
method in water-based detection. We include case studies where detecting other
forensic targets have been searched for; from metal (guns, knives) to those of a nonmetallic
nature, such as submerged barrels/packages of explosives, drugs, contraband
and items that cause environmental pollution. A combination of the consideration of the
environment, the target(s), and both modern and traditional search devices, leads to a
preliminary aqueous search strategy for forensic targets. With further experimental
research and criminal/humanitarian casework, this strategy will continue to evolve and
improve our detection of forensic targets
Draft genome sequences of 25 Listeria monocytogenes isolates associated with human clinical Listeriosis in Ireland
Listeria monocytogenes is a Gram-positive opportunistic pathogen that is the causative agent of listeriosis. Here, we report the draft genome sequences of 25 L. monocytogenes strains isolated from patients with clinical listeriosis in the Republic of Ireland between 2013 and 201
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