14,108 research outputs found
Migration, distribution and breeding of American woodcock
Woodcock are widely distributed over Tennessee, but are most common during fall and spring in the Great Valley, Central Basin, and throughout western Tennessee. Harvest records indicate that peak fall migration occurs in mid-November. In 1977 and 1978, spring migration began during mid-February, and ended during mid-March. Peak migration occurred in late February or early March, but this chronology may not be representative of normal years. Testes lengths averaged 9.2 mm, indicating that male woodcock are in breeding condition by mid-February. Follicle development suggested that 44 percent of the females collected in February 1977 and 52 percent of the females collected in February 1978 were rapidly approaching nesting. The breeding season began during mid-February and lasted until late May. Peak nesting occurs from early to mid-March. Temperatures near 0°C curtailed breeding activity. Courtship activity began an average of 12.6 minutes after sunset; mean light intensity was 3.2 foot candles. Stands of second growth hardwoods found in poorly drained areas were favored diurnal coverts. Singing grounds were frequently early succession old fields, although pastures and other open areas were also used. Most nests were in young hardwood stands and were less than 50 m from a singing ground. Four of 5 broods were in honeysuckle thickets and were less than 50 m from streams
Barley germination:Spatio-temporal considerations for designing and interpreting 'omics' experiments
Serpin genes AtSRP2 and AtSRP3 are required for normal growth sensitivity to a DNA alkylating agent in Arabidopsis
<p>Abstract</p> <p>Background</p> <p>The complex responses of plants to DNA damage are incompletely understood and the role of members of the serpin protein family has not been investigated. Serpins are functionally diverse but structurally conserved proteins found in all three domains of life. In animals, most serpins have regulatory functions through potent, irreversible inhibition of specific serine or cysteine proteinases via a unique suicide-substrate mechanism. Plant serpins are also potent proteinase inhibitors, but their physiological roles are largely unknown.</p> <p>Results</p> <p>Six <it>Arabidopsis </it>genes encoding full-length serpins were differentially expressed in developing seedlings and mature tissues. Basal levels of <it>AtSRP2 </it>(At2g14540) and <it>AtSRP3 </it>(At1g64030) transcripts were highest in reproductive tissues. <it>AtSRP2 </it>was induced 5-fold and <it>AtSRP3 </it>100-fold after exposure of seedlings to low concentrations of methyl methanesulfonate (MMS), a model alkylating reagent that causes DNA damage. Homozygous T-DNA insertion mutants <it>atsrp2 </it>and <it>atsrp3 </it>exhibited no differential growth when mutant and wild-type plants were left untreated or exposed to γ-radiation or ultraviolet light. In contrast, <it>atsrp2 </it>and <it>atsrp3 </it>plants exhibited greater root length, leaf number and overall size than wild-type plants when exposed to MMS. Neither of the two serpins was required for meiosis. GFP-AtSRP2 was localized to the nucleus, whereas GFP-AtSRP3 was cytosolic, suggesting that they target different proteinases. Induction of cell cycle- and DNA damage-related genes <it>AtBRCA1</it>, <it>AtBARD1</it>, <it>AtRAD51</it>, <it>AtCYCB1;1 </it>and <it>AtCYCD1;1</it>, but not <it>AtATM</it>, was reduced relative to wild-type in <it>atsrp2 </it>and <it>atsrp3 </it>mutants exposed to MMS.</p> <p>Conclusion</p> <p>Expression of specific serpin genes (<it>AtSRP2 </it>and <it>AtSRP3 </it>in <it>Arabidopsis</it>) is required for normal responses of plants following exposure to alkylating genotoxins such as MMS.</p
The effect of a decaffeinated green tea extract formula on fat oxidation, body composition and exercise performance
Background:
The cardio-metabolic and antioxidant health benefits of caffeinated green tea (GT) relate to its catechin polyphenol content. Less is known about decaffeinated extracts, particularly in combination with exercise. The aim of this study was therefore to determine whether a decaffeinated green tea extract (dGTE) positively influenced fat oxidation, body composition and exercise performance in recreationally active participants.
Methods:
Fourteen, recreationally active males participated in a double-blind, placebo-controlled, parallel design intervention (mean±SE; age = 21.4±0.3 yrs; weight = 76.37±1.73 kg; body fat = 16.84±0.97 %, peak oxygen consumption [V̇O2peak] = 3.00±0.10 L·min-1). Participants were randomly assigned capsulated dGTE (571 mg·d-1; n=7) or placebo (PL; n=7) for 4 weeks. Following body composition and resting cardiovascular measures, participants cycled for 1 hour at 50% V̇O2peak, followed by a 40 minute performance trial at week 0, 2 and 4. Fat and carbohydrate oxidation was assessed via indirect calorimetry. Pre-post exercise blood samples were collected for determination of total fatty acids (TFA). Distance covered (km) and average power output (W) were assessed as exercise performance criteria.
Results:
Total fat oxidation rates increased by 24.9 % from 0.241±0.025 to 0.301±0.009 g·min-1 with dGTE (P=0.05; ηp2 = 0.45) by week 4, whereas substrate utilisation was unaltered with PL. Body fat significantly decreased with dGTE by 1.63±0.16 % in contrast to PL over the intervention period (P<0.001; ηp2 = 0.84). No significant changes for FFA or blood pressure between groups were observed. dGTE resulted in a 10.9 % improvement in performance distance covered from 20.23±0.54 km to 22.43 ± 0.40 km by week 4 (P<0.001; ηp2 = 0.85).
Conclusions:
A 4 week dGTE intervention favourably enhanced substrate utilisation and subsequent performance indices, but did not alter TFA concentrations in comparison to PL. The results support the use of catechin polyphenols from dGTE in combination with exercise training in recreationally active volunteers
Springs of Florida
bulletin
which documented the major and important springs in the state (Ferguson et al., 1947).
This publication was revised in 1977, with many previously undocumented springs and
many new water-quality analyses being added (Rosenau et al., 1977). The Florida
Geological Survey's report on first magnitude springs (Scott et al., 2002) was the initial step
in once again updating and revising the Springs of Florida bulletin. The new bulletin
includes the spring descriptions and water-quality analyses from Scott et al. (2002). Nearly
300 springs were described in 1977. As of 2004, more than 700 springs have been recognized
in the state and more are reported each year. To date, 33 first magnitude springs (with a
flow greater than 100 cubic feet per second or approximately 64.6 million gallons of water
per day) have been recognized in Florida, more than any other state or country (Rosenau et
al., 1977). Our springs are a unique and invaluable natural resource. A comprehensive
understanding of the spring systems will provide the basis for their protection and wise use.
(Document pdf contains 677 pages
Evaluating multiple causes of persistent low microwave backscatter from Amazon forests after the 2005 drought
Amazonia has experienced large-scale regional droughts that affect forest productivity and biomass stocks. Space-borne remote sensing provides basin-wide data on impacts of meteorological anomalies, an important complement to relatively limited ground observations across the Amazon’s vast and remote humid tropical forests. Morning overpass QuikScat Ku-band microwave backscatter from the forest canopy was anomalously low during the 2005 drought, relative to the full instrument record of 1999–2009, and low morning backscatter persisted for 2006–2009, after which the instrument failed. The persistent low backscatter has been suggested to be indicative of increased forest vulnerability to future drought. To better ascribe the cause of the low post-drought backscatter, we analyzed multiyear, gridded remote sensing data sets of precipitation, land surface temperature, forest cover and forest cover loss, and microwave backscatter over the 2005 drought region in the southwestern Amazon Basin (4°-12°S, 66°-76°W) and in adjacent 8°x10° regions to the north and east. We found moderate to weak correlations with the spatial distribution of persistent low backscatter for variables related to three groups of forest impacts: the 2005 drought itself, loss of forest cover, and warmer and drier dry seasons in the post-drought vs. the pre-drought years. However, these variables explained only about one quarter of the variability in depressed backscatter across the southwestern drought region. Our findings indicate that drought impact is a complex phenomenon and that better understanding can only come from more extensive ground data and/or analysis of frequent, spatially-comprehensive, high-resolution data or imagery before and after droughts
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