3,766 research outputs found
Corepressor diversification by alternative mRNA splicing is species specific.
BackgroundSMRT and NCoR are corepressor paralogs that help mediate transcriptional repression by a variety of transcription factors, including the nuclear hormone receptors. The functions of both corepressors are extensively diversified in mice by alternative mRNA splicing, generating a series of protein variants that differ in different tissues and that exert different, even diametrically opposite, biochemical and biological effects from one another.ResultsWe report here that the alternative splicing previously reported for SMRT appears to be a relatively recent evolutionary phenomenon, with only one of these previously identified sites utilized in a teleost fish and a limited additional number of the additional known sites utilized in a bird, reptile, and marsupial. In contrast, extensive SMRT alternative splicing at these sites was detected among the placental mammals. The alternative splicing of NCoR previously identified in mice (and shown to regulate lipid and carbohydrate metabolism) is likely to have arisen separately and after that of SMRT, and includes an example of convergent evolution.ConclusionsWe propose that the functions of both SMRT and NCoR have been diversified by alternative splicing during evolution to allow customization for different purposes in different tissues and different species
Preliminary Survey of the Terrestrial Isopods (Isopoda), Millipedes (Diplopoda), Harvestmen (Opiliones), and Spiders (Araneae) of Toft Point Natural Area, Door County, Wisconsin
Toft Point Natural Area is a National Natural Landmark owned and managed by the University of Wisconsin – Green Bay and located on the Lake Michigan shore of Wisconsin’s Door Peninsula. With twelve biotic communities on 700 acres, Toft Point contains considerable biological diversity. We conducted a preliminary survey of the arachnids (spiders and harvestmen, excluding mites and pseudoscorpions), millipedes (diplopods), and terrestrial isopods (Isopoda: Oniscoidea).
Sampling occurred on three dates in 2001 using leaf litter collection with Berlese extraction and a timed collection by hand that incorporated a variety of techniques. Specimens from a 1992 survey and assorted collecting events were also used to compile a species list. The list includes five isopods, four millipedes, six harvestmen, and 113 spiders, including 16 new state records (two millipedes and 14 spiders) and 90 new Door County records. Litter collection and sampling in wetland habitats were both especially productive
An Intact Dissecting Baker\u27s Cyst Mimicking Recurrent Deep Vein Thrombosis
We report a case of a 75-year-old female with a history of acute deep vein thrombosis (DVT) 6 years ago who presented with unilateral calf swelling and pain. D-dimer was normal, and compression ultrasound revealed findings typical of DVT, including an incompressible dilated and hypoechoic peroneal vein. Despite 4 months of anticoagulation for supposed recurrent DVT, pain symptoms persisted and repeat D-dimer and compression ultrasound were unchanged. A magnetic resonance imaging scan to investigate the leg demonstrated a 6-cm dissecting Baker\u27s cyst extending posterolaterally resulting in venous compression and distal dilation, which appeared to have been confused with a DVT. Ultrasound-guided aspiration of the cyst provided immediate and sustained relief. Herein we provide a review of the literature for the management of this rare scenario
Equidistribution in All Dimensions of Worst-Case Point Sets for the TSP
Given a set S of n points in the unit square [0, 1]d , an optimal traveling salesman tour of S is a tour of S that is of minimum length. A worst-case point set for the Traveling Salesman Problem in the unit square is a point set S(n) whose optimal traveling salesman tour achieves the maximum possible length among all point sets S ⊂ [0, 1]d , where |S| = n. An open problem is to determine the structure of S(n) . We show that for any rectangular parallelepiped R contained in [0, 1]d , the number of points in S(n) ∩ R is asymptotic to n times the volume of R. Analogous results are proved for the minimum spanning tree, minimum-weight matching, and rectilinear Steiner minimum tree. These equidistribution theorems are the first results concerning the structure of worst-case point sets like S(n)
Preliminary Survey of the Terrestrial Isopods (Isopoda), Millipedes (Diplopoda), Harvestmen (Opiliones), and Spiders (Araneae) of Toft Point Natural Area, Door County, Wisconsin
Toft Point Natural Area is a National Natural Landmark owned and managed by the University of Wisconsin – Green Bay and located on the Lake Michigan shore of Wisconsin’s Door Peninsula. With twelve biotic communities on 700 acres, Toft Point contains considerable biological diversity. We conducted a preliminary survey of the arachnids (spiders and harvestmen, excluding mites and pseudoscorpions), millipedes (diplopods), and terrestrial isopods (Isopoda: Oniscoidea).
Sampling occurred on three dates in 2001 using leaf litter collection with Berlese extraction and a timed collection by hand that incorporated a variety of techniques. Specimens from a 1992 survey and assorted collecting events were also used to compile a species list. The list includes five isopods, four millipedes, six harvestmen, and 113 spiders, including 16 new state records (two millipedes and 14 spiders) and 90 new Door County records. Litter collection and sampling in wetland habitats were both especially productive
Mapping and Assessing Fire Damage on Broadleaved Forest Communities in Big Cypress National Preserve
Within Big Cypress National Preserve (BICY), oak-dominated forests and woodlands as well as tropical and temperate hardwood hammocks are integral components of the landscape and are biodiversity hotpots for both flora and fauna. These broadleaved forest communities serve as refugia for many of the Preserve’s wildlife species during prolonged flooding and fires. However, both prolonged flooding and severe fires, which are important and necessary disturbance vectors within this landscape, can have deleterious effects on these forested communities. This is particularly true in the case of fires, which under extreme conditions associated with drought and elevated fuel loads, can burn through these forested communities consuming litter and understory vegetation and top killing most, if not all, of the trees present
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Genome-wide profiling of human cap-independent translation-enhancing elements.
We report an in vitro selection strategy to identify RNA sequences that mediate cap-independent initiation of translation. This method entails mRNA display of trillions of genomic fragments, selection for initiation of translation and high-throughput deep sequencing. We identified >12,000 translation-enhancing elements (TEEs) in the human genome, generated a high-resolution map of human TEE-bearing regions (TBRs), and validated the function of a subset of sequences in vitro and in cultured cells
The influence of self-citation corrections on Egghe's g index
The g index was introduced by Leo Egghe as an improvement of Hirsch's index h
for measuring the overall citation record of a set of articles. It better takes
into account the highly skewed frequency distribution of citations than the h
index. I propose to sharpen this g index by excluding the self-citations. I
have worked out nine practical cases in physics and compare the h and g values
with and without self-citations. As expected, the g index characterizes the
data set better than the h index. The influence of the self-citations appears
to be more significant for the g index than for the h index.Comment: 9 pages, 2 figures, submitted to Scientometric
Cape Sable Seaside Sparrow Habitat Monitoring and Assessment - 2010 Final Report
For the last two decades, the Cape Sable seaside sparrow (CSSS), a federally endangered species, has been a pivot point for water management operations in the Everglades, primarily because a decline in sparrow population in the early 1990s was attributed in part to managementinduced alterations in hydrologic regimes. With a goal of understanding the response of landscape-level processes to hydrological restoration and its interaction with fire, a study intended to monitor vegetation structure and composition throughout the marl prairie landscape has been conducted since 2003 with funding from U.S. Army Corps of Engineers (USACE). In the first three years (2003-2005), vegetation structure and composition was characterized in relation to the existing hydrologic regime and fire history. During 2006-2010, vegetation was resampled to assess vegetation change within the sparrow habitat. This document summarizes the vegetation change pattern observed between the two sampling periods in sub-population A, C, E and F, emphasizing the work accomplished in FY 2010
High Intensity Exercise Countermeasures does not Prevent Orthostatic Intolerance Following Prolonged Bed Rest
Approximately 20% of Space Shuttle astronauts became presyncopal during operational stand and 80deg headup tilt tests, and the prevalence of orthostatic intolerance increases after longer missions. Greater than 60% of the US astronauts participating in Mir and early International Space Station missions experienced presyncope during postflight tilt tests, perhaps related to limitations of the exercise hardware that prevented high intensity exercise training until later ISS missions. The objective of this study was to determine whether an intense resistive and aerobic exercise countermeasure program designed to prevent cardiovascular and musculoskeletal deconditioning during 70 d of bed rest (BR), a space flight analog, would protect against postBR orthostatic intolerance. METHODS Twentysix subjects were randomly assigned to one of three groups: nonexercise controls (n=11) or one of two exercise groups (ExA, n=8; ExB, n=7). Both ExA and ExB groups performed the same resistive and aerobic exercise countermeasures during BR, but one exercise group received testosterone supplementation while the other received a placebo during BR in a doubleblinded fashion. On 3 d/wk, subjects performed lower body resistive exercise and 30 min of continuous aerobic exercise (75% max heart rate). On the other 3 d/wk, subjects performed only highintensity, intervalstyle aerobic exercise. Orthostatic intolerance was assessed using a 15min 80 headup tilt test performed 2 d (BR2) before and on the last day of BR (BR70). Plasma volume was measured using carbon monoxide rebreathing on BR3 and before rising on the first recovery day (BR+0). The code for the exercise groups has not been broken, and results are reported here without group identification. RESULTS Only one subject became presyncopal during tilt testing on BR2, but 7 of 11 (63%) controls, 3 of 8 (38%) ExA, and 4 of 7 (57%) ExB subjects were presyncopal on BR70. Survival analysis of postBR tilt tests revealed no differences (p=0.77) between groups. Plasma volume (absolute or relative to body mass index) decreased (p<0.001) from pre to postBR, with no differences between groups. CONCLUSIONS These preliminary results corroborate previous reports that the performance of a vigorous exercise countermeasure protocol during BR, even with testosterone supplementation, does not protect against orthostatic intolerance or plasma volume loss. Preventing postBR orthostatic intolerance may require additional countermeasures, such as orthostatic stress during BR or endofBR fluid infusion
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