bluuebunny/crossref_metadata_2025 huggingface dataset:
High Conservation Value or high confusion value? Sustainable agriculture and biodiversity conservation in the tropics
Authors: Edwards David P. , Fisher Brendan , Wilcove David S.
Published: November 2011

Green labeling of products that have been produced sustainably is an emerging tool of the environmental movement. A prominent example is the Forest Stewardship Council, which certifies timber that is harvested to manage and maintain forests defined as having High Conservation Value (HCV). The criteria for HCV are now being applied to four rapidly expanding crops in the tropics: oil palm, soy, sugarcane, and cacao. However, these criteria do not provide adequate protection for biodiversity when applied to agriculture. The only criterion that provides blanket protection to forests is one that protects large expanses of habitat (≥20,000–500,000 ha, depending on the country). Absent of other HCVs, the collective clearing of forest patches below these thresholds could result in extensive deforestation that would be sanctioned with a green label. Yet such forest patches retain much biodiversity and provide connectivity within the agricultural matrix. An examination of forest fragments in biodiverse countries across the tropics shows that future agricultural demand can be met by clearing only forest patches below a 1,000 ha threshold. We recommend the development of a new HCV criterion that recognizes the conservation value of habitat patches within the agricultural matrix and that protects patches above 1,000 ha.
Integrating diet and movement data to identify hot spots of predation risk and areas of conservation concern for endangered species
Authors: Ward Eric J. , Levin Phillip S. , Lance Monique M. , Jeffries Steven J. , Acevedo‐Gutiérrez Alejandro
Published: November 2011

Effective management of threatened and endangered species requires an understanding of how species of conservation concern are distributed spatially, as well as the spatial distribution of risks to the population, such as predation or human impacts (fishing, pollution, and loss of habitat). Identifying high‐risk areas is particularly important when designing reserves or protected areas. Our novel approach incorporates data on distribution, movement, and diet of a generalist marine predator (harbor seals) to identify and map “hot spots” of predation risk for an endangered prey species (rockfish). Areas with high concentrations of seals (including some current marine reserves) are also estimated hot spots for rockfish predation. Although marine reserve planning currently targets areas with good habitat and low human disturbance, our modeling suggests that future terrestrial and marine reserve design may be made more effective by incorporating other components of the food web that either directly or indirectly interact with target species.
Morphological, palynological, seed‐coat surface and karyological studies of Hesperis bicuspidata and H. stellata (Cruciferae) from Turkey
Authors: Duran Ahmet , Ünal Fatma , Pinar Nur Münevver , Çetin Özlem
Published: November 2011

The taxonomic delimitation of Hesperis bicuspidata (Willd.) Poir. and H. stellata F. Dvořák is problematic, and we therefore studied morphological, palynological, seed‐coat surface and karyological features of both species to determine their degree of similarity. The morphology was described using 13 characters, each based on ten measurements on different specimens. Hesperis stellata and H. bicuspidata both show large variation in vegetative and reproductive organs; petal length varies between 18 and 26 mm and petal width is 3–7 mm; the corolla is lilac, whitish lilac, violet, dark violet or white in color, and fruits of both species are generally glabrous or have very short bifurcate hairs. Pollen and seed morphology were examined by LM and SEM. Pollen of both species is prolate‐spheroid or subprolate, tricolpate and reticulate. Their exine structures are the same. Hesperis bicuspidata is diploid (2n=14) but different chromosome types were present in the two studied specimens. Hesperis stellata is tetraploid (2n=28) showing the same chromosome types as the samples of H. bicuspidata. Eighteen morphometrical characters of H. bicuspidata, H. stellata, H. pisidica and H. armena were analysed by ANOVA. Notes on ecology and distribution are also presented for H. bicuspidata. Based on the results, H. stellata is reduced to a synonym of H. bicuspidata.
Morphological variation in populations of the Poa orinosa complex (Poaceae: Poeae) in northeastern China
Authors: Olonova Marina V. , Barkworth Mary E. , Pulkina S. V. , Chen Wen‐Li
Published: November 2011

We conducted a detailed study of the morphological and cytological variation in seven populations of the Poa orinosa complex along an ecological gradient in northeastern China. Three of the populations were at different elevations in wooded habitats; three were in habitats dominated by grasses other than Poa; and one was in a shrub–steppe habitat. Plants from two of the wooded sites were diploid; those from the third wooded site were primarily octoploid. Plants from two of the grassy sites were tetraploid; those from the third grassy site were hexaploid. The seventh population, located in a shrub–steppe habitat, was diploid. Twenty‐four morphological characters were scored on specimens from each site. Plants from the three wooded sites and the lowest grassy site differed from those from the other three sites in having longer culms, internodes and sheaths. The similarity of the tetraploid plants to the diploid plants suggested that they may be autotetraploids. Similarly, the morphological similarity of the octoploid population to the two diploid populations suggested that it too may be an autopolyploid. The morphological distinction of the hexaploid population suggests that it has incorporated a genome not present in the other populations.
Shoulder Strength Testing: The Intra- and Inter-tester Reliability of Routine Clinical Tests, Using the PowertrackTM II Commander
Authors: Dollings Hannah , Sandford Fiona , O'conaire Eoin , Lewis Jeremy S.
Published: November 2011

Background

To assess intra- and inter-tester reliability of measuring shoulder strength using a new hand-held dynamometer.

Methods

On two occasions, two examiners (blinded to output) measured seven separate tests of shoulder strength. Twenty-three participants with no shoulder symptoms were tested bilaterally. Each test was performed three times as a ‘make test’ using a hand-held digital dynamometer.

Results

Intraclass correlation coefficients (2,1) and (2,3), 95% confidence intervals and standard errors of measurements (SEM) demonstrated good intra- and inter-tester reliability of all tests [ICC(2,3) >0.87], with the exception of inter-tester reliability of right abduction [ICC(2,3) = 0.77]. Greater reliability of all tests was demonstrated when the mean of three trials was used compared to the first measurement. Intra-tester reliability of all tests using ICC(2,1) ranged from 0.74 to 0.98; ICC(2,3) ranged from 0.89 to 0.98. Inter-tester reliability using ICC(2,1) ranged from 0.52 to 0.94; ICC(2,3) ranged from 0.77 to 0.96. The smallest detectable difference (SDD), used to measure precision, ranged from 5.9 to 12.5 Newtons.

Discussion

The findings obtained in the present study suggest that using the methods employed in the population investigated demonstrated good to excellent intra- and inter-tester reliability for the measurement of shoulder strength. The SEM and SDD findings provide guidance for values that may be considered as a real change in strength.
Molecular mechanisms of Staphylococcus aureus nasopharyngeal colonization
Authors: Edwards A.M. , Massey R.C. , Clarke S.R.
Published: November 2011

Staphylococcus aureus is responsible for a wide range of different infections ranging in severity from mild to fatal. However, it primarily exists as a commensal organism in a number of different anatomical sites including the nasopharynx. Although colonization itself is a harmless state, colonized individuals are at risk of endogenous infection when S. aureus enters otherwise sterile sites via wounds or indwelling medical devices. As such, studies of colonization may identify important targets for vaccines or other prophylactic approaches. Colonization is a dynamic process; S. aureus must attach to host surfaces, overcome immune components and compete with other commensal microbes. This occurs via a number of surface‐attached and secreted proteins and other factors such as wall teichoic acid. In addition, colonizing S. aureus must constantly replicate to maintain its niche and exclude other strains. These myriad interactions provide a strong selective pressure for the maintenance or enhancement of mechanisms of adhesion, invasion and immune evasion. The evolutionary implications of this may explain why S. aureus is such a capable pathogen because many of the proteins involved in colonization have also been identified as virulence factors. This review describes the diverse molecular mechanisms used by S. aureus to colonize the host and discusses how the pressures that have selected for these may have led to its virulence.
Association between cigarette smoking and the intraoral distribution of periodontal disease in Thai men over 50 years of age
Authors: Torrungruang Kitti , Gongsakdi Vidhita , Laohaviraphab Leela , Likittanasombat Khanchit , Ratanachaiwong Wipa
Published: November 2011

Aim:  This study aimed to investigate the effects of cigarette smoking on periodontal conditions in specific tooth regions of older Thai men.

Methods:  There were 272 current smokers, 714 former smokers, and 477 non‐smokers enrolled in the present study. Differences between groups in the mean probing depth or attachment loss were compared using ancova. The relationship between smoking exposure or cessation duration and periodontal conditions was examined using linear trend analysis.

Results:  Smokers had deeper pockets and attachment loss than non‐smokers. The greatest differences between smokers and non‐smokers were observed in the maxillary posterior palatal region, where current smokers had 0.88 mm greater attachment loss than non‐smokers, compared to 0.36–0.60 mm observed in other tooth regions. Among the current smokers, there was a trend towards an increase in attachment loss with increasing smoking exposure in the maxillary posterior regions. However, it was not statistically significant. Among the former smokers, a better periodontal condition was observed, depending on the length of time since smoking cessation; this was most pronounced in the maxillary posterior palatal region.

Conclusions:  The palatal site of maxillary posterior teeth was the area most affected by cigarette smoke. The results suggest a possible local effect of smoking in addition to its systemic effects.
Colic in competing endurance horses presenting to referral centres: 36 cases
Authors: FIELDING C. L. , DECHANT J. E.
Published: November 2011

Reasons for performing study:Colic is a common reason for elimination from equine endurance competitions and has recently been identified as the leading cause of mortality in this group of horses. Hydration and electrolyte derangements are often severe, but are probably related to endurance exercise and not necessarily the episode of colic. Better understanding of the causes of colic and the expected outcome is needed to guide treatment decisions in endurance horses.

Objectives:To describe the history, case details, clinical examination, laboratory, treatment and outcomes for horses presenting to equine referral centres for treatment of colic associated with endurance competition and to identify variables associated with prolonged hospitalisation.

Methods:Thirty‐six horses from 2 equine referral centres were included in the analysis. In addition to descriptive statistics, Cox proportional hazards models were used to evaluate factors associated with length of hospitalisation.

Results:A diagnosis of open or ileus was made in the majority of horses (56%). Salmonellosis and enteritis (Salmonellanegative) were also recognised (16%). Exploratory abdominal surgery was performed in 5 of the horses. Only one of 36 horses did not survive to discharge. Previous eliminations from competition (negative association) and total i.v. fluids within the first 24 h (positive association) of admission were both associated with length of hospitalisation.

Conclusions:Endurance horses with colic typically respond to medical treatment but in some cases hospitalisation may be prolonged. The role ofSalmonellainfections in endurance horses with colic requires further research.

Potential relevance:Despite potentially severe clinical and laboratory derangements, equine practitioners should make owners aware that the prognosis for competing endurance horses with colic is good when treated appropriately.
Experimental Investigation of Turbulent Boundary Layer Flashback Limits for Premixed Hydrogen-Air Flames Confined in Ducts
Authors: Eichler Christian , Baumgartner Georg , Sattelmayer Thomas
Published: November 2011

The design of flashback-resistant premixed burners for hydrogen-rich fuels is strongly dependent on reliable turbulent boundary layer flashback limits, since this process can be the dominant failure type for mixtures with high burning velocities. So far, the flashback data published in literature is based on tube burner experiments with unconfined flames. However, this flame configuration may not be representative for the most critical design case, which is a flame being already present inside the duct geometry. In order to shed light on this potential misconception, boundary layer flashback limits have been measured for unconfined and confined flames in fully premixed hydrogen-air mixtures at atmospheric conditions. Two duct geometries were considered, a tube burner and a quasi-2D turbulent channel flow. Furthermore, two confined flame holding configurations were realized, a small backward-facing step inside the duct and a ceramic tile at high temperature, which was mounted flush with the duct wall. While the measured flashback limits for unconfined tube burner flames compare well with literature results, a confinement of the stable flame leads to a shift of the flashback limits towards higher critical velocity gradients, which are in good agreement between the tube burner and the quasi-2D channel setup. The underestimation of flashback propensity resulting from unconfined tube burner experiments emerges from the physical situation at the burner rim. Heat loss from the flame to the wall results in a quenching gap, which causes a radial leakage flow of fresh gases. This flow in turn tends to increase the quenching distance, since it constitutes an additional convective heat loss. On the one hand, the quenching gap reduces the local adverse pressure gradient on the boundary layer. On the other hand, the flame base is pushed outward, which deters the flame from entering the boundary layer region inside the duct. The flashback limits of confined flames stabilized at backward-facing steps followed this interpretation, and experiments with a flush ceramic flame holder constituted the upper limit of flashback propensity. It is concluded that the distribution of the flame backpressure and the flame position itself are key parameters for the determination of meaningful turbulent boundary layer flashback limits. For a conservative design path, the present results obtained from confined flames should be considered instead of unconfined tube burner values.
Geometric Hysteresis of Alveolated Ductal Architecture
Authors: Kojic M. , Butler J. P. , Vlastelica I. , Stojanovic B. , Rankovic V. , Tsuda A.
Published: November 2011

Low Reynolds number airflow in the pulmonary acinus and aerosol particle kinetics therein are significantly conditioned by the nature of the tidal motion of alveolar duct geometry. At least two components of the ductal structure are known to exhibit stress-strain hysteresis: smooth muscle within the alveolar entrance rings, and surfactant at the air-tissue interface. We hypothesize that the geometric hysteresis of the alveolar duct is largely determined by the interaction of the amount of smooth muscle and connective tissue in ductal rings, septal tissue properties, and surface tension-surface area characteristics of surfactant. To test this hypothesis, we have extended the well-known structural model of the alveolar duct by Wilson and Bachofen (1982, “A Model for Mechanical Structure of the Alveolar Duct,” J. Appl. Physiol. 52(4), pp. 1064–1070) by adding realistic elastic and hysteretic properties of (1) the alveolar entrance ring, (2) septal tissue, and (3) surfactant. With realistic values for tissue and surface properties, we conclude that: (1) there is a significant, and underappreciated, amount of geometric hysteresis in alveolar ductal architecture; and (2) the contribution of smooth muscle and surfactant to geometric hysteresis are of opposite senses, tending toward cancellation. Quantitatively, the geometric hysteresis found experimentally by Miki et al. (1993, “Geometric Hysteresis in Pulmonary Surface-to-Volume Ratio during Tidal Breathing,” J. Appl. Physiol. 75(4), pp. 1630–1636) is consistent with little or no smooth muscle tone in anesthetized rabbits in control conditions, and with substantial smooth muscle activation following methacholine challenge. The observed local hysteretic boundary motion of the acinar duct would result in irreversible acinar flow fields, which might be important mechanistic contributors to aerosol mixing and deposition deep in the lung.
Deep Human Genealogies Reveal a Selective Advantage to Be on an Expanding Wave Front
Authors: Moreau Claudia , Bhérer Claude , Vézina Hélène , Jomphe Michèle , Labuda Damian , Excoffier Laurent
Published: November 2011

Women in the vanguard of range expansions, such as the European settlement of Quebec, married young and had more offspring.
Two cases of opportunistic parasite infections in patients receiving alemtuzumab
Authors: Desoubeaux Guillaume , Caumont Charline , Passot Christophe , Dartigeas Caroline , Bailly Éric , Chandenier Jacques , Duong Thanh Haï
Published: November 2011

Two cases are reported of rare digestive opportunistic parasites in patients being treated with alemtuzumab for lymphoid haematological malignancies. In both patients, classical biological examinations were insufficient to reach the diagnosis. Only specific parasitological techniques enabled diagnoses of cryptosporidiosis and microsporidiosis, respectively. In both cases, cellular immune reconstitution was sufficient to eradicate these opportunistic infections. In this context, parasitological diagnosis is often underestimated by medical practitioners, so immunologists and oncohaematologists need to be aware of this kind of opportunistic pathogen.
A checklist for cerebral aneurysm embolization complications
Authors: Chen Michael
Published: November 2011

Complications during cerebral aneurysm embolization continue to occur even at high volume experienced centers. Such situations are unexpected, complex and can have devastating consequences. Individual anecdotal experience offers limited guidance. This literature review of the two most serious neuroendovascular procedural complications—namely, aneurysm perforation and thromboemboli—aims to propose a role based checklist. Having a premeditated plan helps team members remain calm and function more effectively when a procedural complication occurs, with the ultimate goal of minimizing patient harm.
Effect of rating scales on scores given to junior doctors in multi-source feedback
Authors: Hassell Andrew , Bullock Alison , Whitehouse Andrew , Wood Lawrence , Jones Peter , Wall David
Published: November 2011

Background

Multi-source feedback (MSF) has an established role in the workplace based assessment of doctors in training. Different models of MSF are currently used in different training programmes and settings. One important way in which these models differ is the rating scale on which assessors score the trainee. The aim of this study was to explore the effect of rating scale on MSF scores.

Methods

Foundation Year 2 trainees in hospitals in the West Midlands underwent MSF using the validated MSF tool, team assessment of behaviour (TAB) in autumn 2005. Trainees were scored with TAB using one of four different rating scales, ranging from 3- to 9-point scales. Each participating hospital used only one rating scale. The proportions of trainees scored as having potential problems were related to the different rating scale used. Similarly, the proportions scored as ‘above expectations’ were compared. Assessors also completed a short questionnaire regarding the assessment.

Results

245 trainees underwent 2594 assessments. Longer rating scales were associated with a lower proportion of trainees awarded ‘problem’ scores and higher proportions of trainees scored as ‘above expectations’. Assessors generally reported no difficulties whichever rating scale they had used.

Conclusion

Careful consideration, recognising its potential impact on assessment score, should be given to the rating scale used when instituting MSF within a system of workplace based assessment.
Primary IgA nephropathy in north India: is it different?
Authors: Mittal Neha , Joshi Kusum , Rane Swapnil , Nada Ritambhra , Sakhuja Vinay
Published: November 2011

Background

Immunoglobulin A (IgA) nephropathy is the most common glomerulonephritis worldwide, but has a variable geographic distribution. The bulk of the disease burden is borne by Asian countries. However, its exact prevalence or clinicopathologic spectrum in India is not well documented.

Methods

This cross sectional study analysed the renal biopsy findings and clinical features at presentation in 66 patients of primary IgA nephropathy diagnosed over a period of 2 years (2007–2008). The results were compared with studies from other centres in the country and elsewhere.

Results

IgA nephropathy comprised 8.1% of all native kidney biopsies. The mean age of the patients was 29.9 years with a male:female ratio of 4.4:1. Most patients presented with renal failure and a significant percentage (23%) also had nephrotic range proteinuria. Renal biopsies were classified by the Haas classification and were further scored by the MEST scoring system of the Oxford classification. By Haas classification, 41 cases (62%) showed advanced sclerotic lesions of class V. Active crescents (cellular or fibrocellular) were seen in 42% of cases, and 26% of cases showed endocapillary proliferation. Serum creatinine values were highest in the presence of proliferative lesions. MEST scoring of the Oxford classification was not applicable in approximately 18% of cases because of the presence of advanced sclerotic lesions. On immunofluorescence, the majority of the cases showed both mesangial and membranous positivity for IgA antisera. Electron microscopy revealed para-mesangial location of immune complex deposition in the majority of the cases. It also showed glomerular basement membrane abnormalities in two cases.

Conclusion

Comparison of clinical and pathological features revealed that this disease presents as an advanced disease in much younger individuals in this study compared to other studies. Elucidation of the underlying factors may have immense therapeutic implications.
Investigating pipeline–soil interaction under axial–lateral relative movements in sand
Authors: Daiyan Nasser , Kenny Shawn , Phillips Ryan , Popescu Radu
Published: November 2011

This paper presents results from an experimental and numerical study on the axial–lateral interaction of pipes with dense sand. A series of centrifuge tests were conducted, with a rigid pipeline displaced in the horizontal plane in a cohesionless test bed. The relative pipe–soil interaction included axial, lateral, and oblique loading events. A three-dimensional continuum finite element model was developed using ABAQUS/Standard ( Hibbitt et al. 2005 ) software. The numerical model was calibrated against experimental results. A parametric study was conducted, using the calibrated finite element model to extend the investigations. The ultimate axial and lateral soil loading was found to be dependent on the angle of attack for relative movement between the pipe and soil. Two different failure mechanisms were observed for axial–lateral pipeline–soil interaction. This study confirms and improves on a two-part failure criterion that accounts for axial–lateral coupling during oblique soil loading events on buried pipelines.
Expression of autophagy-related genes in the anterior silk gland of the silkworm (Bombyx mori) during metamorphosis
Authors: Li Qingrong , Deng Xiaojuan , Huang Zhijun , Zheng Sichun , Tettamanti Gianluca , Cao Yang , Feng Qili
Published: November 2011

Programmed cell death (PCD) is a genetically regulated process of cell elimination and is evolutionarily conserved in eukaryotes. Degeneration of larval tissues during metamorphosis in insects is a result of PCD triggered by ecdysteroids and autophagic process has been shown to be involved in the degeneration of silk gland of the silkworm ( Bombyx mori L., 1758). However, experimental evidence for the expression of autophagy marker genes remains insufficient. In this study, expression of the autophagy-related genes BmAtg5, BmAtg6, BmAtg8, and BmAtg12 was determined in the anterior silk glands of larvae and pupae during larval to pupal transformation by using reverse-transcription PCR, quantitative real-time PCR, and Western blot analyses. The results indicated that BmAtg5, BmAtg6, BmAtg8, and BmAtg12 had the highest expression levels on the 3rd day of the wandering stage or at the prepupal stage, and the time frame of the expression of these genes was coincident with the morphological characteristics of autophagy in the silk gland during the larval to pupal transformation. This study demonstrated that the autophagy-related genes are involved in the degeneration of the anterior silk gland of B. mori.
Drifting away: implications of changes in ice conditions for a pack-ice-breeding phocid, the harp seal (Pagophilus groenlandicus)
Authors: Bajzak C.E. , Hammill M.O. , Stenson G.B. , Prinsenberg S.
Published: November 2011

Harp seals ( Pagophilus groenlandicus (Erxleben, 1777)) required drifting pack-ice for birth, nursing, and as a resting platform for neonates after weaning. Data on the yearly location of whelping patches in the Gulf of St. Lawrence collected between 1977 and 2011 were combined with ice cover data (thickness and duration) to examine whether female harp seals actively select particular ice features as a breeding platform and to describe how these ice features have varied over the last 40 years at three spatial scales: the entire Gulf of St. Lawrence, the southern gulf, and the “traditional whelping area” within the southern Gulf. From our analyses, harp seals prefer the thickest ice stages available in the Gulf: grey–white and first-year ice. Lower than normal ice coverage years were more frequent for the required grey–white and first-year ice than for the total ice cover and less frequent at the “traditional whelping area” scale close to the northwestern coast of the Magdalen Islands than at the Gulf of St. Lawrence scale. The frequency of light ice years increased and the duration of the ice season decreased throughout the last decade. Our study showed that the temporal availability and the spatial distribution of the suitable ice are important when evaluating the effect of changes in ice conditions rather than overall ice extent.
Effects of parasites on host energy expenditure: the resting metabolic rate stalemate
Authors: Robar Nicholas , Murray Dennis L. , Burness Gary
Published: November 2011

Detrimental effects of parasitism on host fitness are frequently attributed to parasite-associated perturbations to host energy budgets. It has therefore been widely hypothesized that energetic costs of infection may be manifest as changes in host resting metabolic rate (RMR). Attempts to quantify these effects have yielded contradictory results across host–parasite systems. We used a meta-analysis of the literature to test the effects of parasites on mass-specific (n = 22) and whole-body (n = 15) host RMR. Parasites resulted in a qualitative increase in host RMR in the majority of studies; however, the overall effect of parasites on host RMR was small and statistically nonsignificant. Additionally, substantial among-study variation in host RMR could not be explained by any of the tested covariates. We conclude that the lack of an overall effect of parasites on host metabolism reflects inconsistent directionality and varying magnitudes of parasite-associated effects across studies, rather than an absence of system-specific effects. We contend that a general understanding of parasite effects on host energetics may be best achieved through identifying mechanisms underlying among-system variance in parasite effects on host RMR and relating parasite-associated perturbations of host energy budgets to robust estimates of host fitness.
Landscape composition and structure influence the abundance of mesopredators: implications for the control of the raccoon (Procyon lotor) variant of rabies
Authors: Houle Mélina , Fortin Daniel , Mainguy Julien , Canac-Marquis Pierre
Published: November 2011

Rabies propagation in Canada has forced wildlife managers to develop intervention strategies to reduce the risk of rabies epizootics. We assessed whether some landscape characteristics of a corn-dominated region of Quebec in which the raccoon variant of rabies (RVR) has spread were associated with the abundances of raccoons ( Procyon lotor (L., 1758)) and striped skunks (Mephitis mephitis (Schreber, 1776)). We then examined whether landscape variables that best explained spatial variation in raccoon abundance were also good predictors in the detection of rabid raccoons. Between June and September 2007, 9600 raccoons and 1612 skunks were captured from 111 trapping cells. The abundance of captured raccoons, especially that of adult males and juveniles, increased over the summer in trapping cells characterized by a high density of forest edges bordering corn fields. The probability of detecting rabid raccoons also increased with this landscape characteristic, as well as with adult raccoon abundance. No landscape characteristic, however, explained spatial variation in skunk abundance. Efficient RVR control operations in similar landscapes should ideally include widespread distribution of vaccine baits because of the general distribution of skunks, while also focusing on areas where forest patches intersperse with corn fields to target high concentrations of raccoons, particularly in late summer.
Northern Pacific Rattlesnakes (Crotalus oreganus) use thermal and structural cues to choose overwintering hibernacula
Authors: Gienger C.M. , Beck Daniel D.
Published: November 2011

Hibernacula play an important role in the ecology of high-latitude snakes, and communally denning species may occupy their hibernacula for half the year or more. Because of the long duration spent at hibernacula, such sites can provide multiple benefits to snakes including shelter from lethal overwinter conditions, social opportunities, and basking sites important in thermoregulation. Adequate hibernacula seem to be limited on the landscape and individuals travel several kilometres to use and reuse specific sites. We investigate orientation, physical structure, and thermal properties of sites used as hibernacula by Northern Pacific Rattlesnakes ( Crotalus oreganus Holbrook, 1840), and compare them with random sites that appear to be similar but were not used for hibernation. Hibernacula occurred primarily on south-facing talus slopes, were oriented on less-steep slopes, and were composed of rocks that were intermediate in size to randomly occurring sites. Our results suggest that the orientation and physical composition of hibernacula allow them to be stable over time, allowing snakes to repeatedly locate the sites, as well as providing predictable overwinter refuge. Hibernacula were also warmer on the surface than north-facing random sites and provided increased basking opportunities for snakes thermoregulating in early spring after emergence from hibernation.
CONSTRUCTING CONSTRAINED DELAUNAY TETRAHEDRALIZATIONS OF VOLUMES BOUNDED BY PIECEWISE SMOOTH SURFACES
Authors: GOSSELIN SERGE , OLLIVIER-GOOCH CARL
Published: November 2011

This article presents an algorithm to construct constrained Delaunay tetrahedralizations of geometric domains bounded by piecewise smooth surfaces. Meshes are built from the bottom-up by first discretizing the boundary curves and then by sampling the smooth surfaces. The sampling procedure refines the Delaunay triangulation restricted to these surfaces, targeting topological violations and poor quality triangles. Unlike previously published algorithms adopting a similar approach, we propose to sample each smooth surface patch independently. This obviates the need for a boundary protection scheme around small dihedral angles in the input and can also lead to coarser constraining triangulations. Starting from a Delaunay tetrahedralization of the point samples, a combination of mesh reconfigurations and vertex insertions is then used to obtain a tetrahedralization constrained to the boundary surfaces. The algorithm is designed to produce tetrahedralizations that can be used in conjunction with a Delaunay refinement algorithm implemented on a Bowyer-Watson framework.
TIME REVERSAL IN NEUTRINO OSCILLATIONS IN MATTER
Authors: HENLEY ERNEST M. , JOHNSON MIKKEL B. , KISSLINGER LEONARD S.
Published: November 2011

We estimate the time reversal violations for neutrino oscillations in matter for typical experimental energies and baselines. We examine the present status of experiments on neutrino oscillations, propose experiments for TRV, and discuss the future.
Resveratrol causes cell cycle arrest, decreased collagen synthesis, and apoptosis in rat intestinal smooth muscle cells
Authors: Garcia Patricia , Schmiedlin-Ren Phyllissa , Mathias Jason S. , Tang Huaijing , Christman Gregory M. , Zimmermann Ellen M.
Published: November 2011

One of the most difficult and treatment-resistant complications of Crohn's disease is the development of fibrotic intestinal strictures due to mesenchymal cell hyperplasia and collagen deposition. Resveratrol, a phytoalexin found in berries, peanuts, grapes, and red wine, has been shown to inhibit fibrosis in vasculature, heart, lung, kidney, liver, and esophagus in animal models. Resveratrol has also been shown to inhibit oxidation, inflammation, and cell proliferation and to decrease collagen synthesis in several cell types or animal models. The aim of this study was to determine whether resveratrol has antifibrotic effects on intestinal smooth muscle cells. Responses to resveratrol by cultured smooth muscle cells isolated from colons of untreated Lewis rats were examined; this rat strain is used in a model of Crohn's disease with prominent intestinal fibrosis. A relative decrease in cell numbers following treatment with 50 and 100 μM resveratrol was evident at 24 h ( P ≤ 0.005). This effect was largely due to cell cycle arrest, with an increase in the percent of cells in S phase from 8 to 25–35% ( P < 0.05). Cell viability was unchanged until 2–3 days of treatment when there was a 1.2- to 5.0-fold increase in the percent of apoptotic cells, depending on the assay ( P < 0.05). Expression of collagen type I protein was decreased following treatment with resveratrol for 24 h (to 44 and 25% of control levels with 50 and 100 μM resveratrol, respectively; P < 0.05). Expression of procollagen types I and III mRNA was also decreased with resveratrol treatment. Resveratrol (50 μM) diminished the proliferative response to TGF-β1( P = 0.02) as well as IGF-I-stimulated collagen production ( P = 0.02). Thus resveratrol decreases intestinal smooth muscle cell numbers through its effects on cell cycle arrest and apoptosis and also decreases collagen synthesis by the cells. These effects could be useful in preventing the smooth muscle cell hyperplasia and collagen deposition that characterize stricture formation in Crohn's disease.
Differential involvement of amygdala corticosteroid receptors in visceral hyperalgesia following acute or repeated stress
Authors: Myers Brent , Greenwood-Van Meerveld Beverley
Published: November 2011

Symptoms of irritable bowel syndrome (IBS) are exacerbated by stress. Previously, we demonstrated that the stress hormone corticosterone applied directly to the amygdala induced visceral hypersensitivity through the actions of glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). However, the involvement of amygdaloid GR and MR in the regulation of visceral sensitivity following psychological stress is unknown; therefore, the goal of the present study was to determine the relative importance of amygdaloid GR and MR in the regulation of visceral sensitivity in a rodent model of behavioral stress. Male F-344 rats were stereotaxically implanted with micropellets bilaterally on the dorsal margin of the amygdala containing the GR antagonist mifepristone, the MR antagonist spironolactone, or cholesterol as a control. Animals were then exposed to 1 h of water-avoidance stress (WAS) or sham stress for 1 day (acute) or 7 days (repeated). Visceral sensitivity was assessed either 1 h or 24 h after the final session of WAS and quantified as the number of contractions of the external abdominal oblique, a visceromotor response, in response to colorectal distension at pressures of 0–60 mmHg. Acute stress induced transient visceral hyperalgesia, which was absent 24 h after WAS and independent of GR and MR. Conversely, repeated WAS induced sustained visceral hyperalgesia that was abolished by specifically targeting the amygdala with GR and MR antagonists. These results demonstrate that the amygdala corticosteroid system plays an essential role in mediating the effects of repeated WAS on visceral sensitivity. Furthermore, our findings suggest that amygdaloid GR and MR may be involved in IBS symptomatology.
PKCδ-dependent activation of ERK1/2 leads to upregulation of the human NHE2 transcriptional activity in intestinal epithelial cell line C2BBe1
Authors: Muthusamy Saminathan , Shukla Sagar , Amin Md. Ruhul , Cheng Ming , Orenuga Temitope , Dudeja Pradeep K. , Malakooti Jaleh
Published: November 2011

The apical Na+/H+exchanger (NHE) isoform NHE2 is involved in transepithelial Na+absorption in the intestine. Our earlier studies have shown that mitogenic agent phorbol 12-myristate 13-acetate (PMA) induces the expression of NHE2 through activation of transcription factor early growth response-1 (Egr-1) and its interactions with the NHE2 promoter. However, the signaling pathways involved in transcriptional stimulation of NHE2 in response to PMA in the intestinal epithelial cells are not known. Chemical inhibitors and genetic approaches were used to investigate the signaling pathways responsible for the stimulation of NHE2 expression by PMA via Egr-1 induction. We show that, in response to PMA, PKCδ, a member of novel PKC isozymes, and MEK-ERK1/2 pathway of mitogen-activated protein kinases stimulate the NHE2 expression in C2BBe1 intestinal epithelial cells. PMA rapidly and transiently induced activation of PKCδ. Small inhibitory RNA-mediated knockdown of PKCδ blocked the stimulatory effect of PMA on the NHE2 promoter activity. In addition, blockade of PKCδ by rottlerin, a PKCδ-specific inhibitor, and ERK1/2 by U0126, a MEK-ERK inhibitor, abrogated PMA-induced Egr-1 expression. Immunofluorescence studies revealed that inhibition of ERK1/2 activation prevents translocation of PMA-induced Egr-1 into the nucleus. Consistent with these data, PMA-induced Egr-1 interaction with the NHE2 promoter region was prevented in nuclear extracts from U0126-pretreated cells. In conclusion, our data provide the first evidence that the stimulatory effect of PMA on NHE2 expression is mediated through the initial activation of PKCδ, subsequent PKCδ-dependent activation of MEK-ERK1/2 signaling pathway, and stimulation of Egr-1 expression. Furthermore, we show that transcription factor Egr-1 acts as an intermediate effector molecule that links the upstream signaling cues to the long-term stimulation of NHE2 expression by PMA in C2BBe1 cells.
Displacement-encoded and manganese-enhanced cardiac MRI reveal that nNOS, not eNOS, plays a dominant role in modulating contraction and calcium influx in the mammalian heart
Authors: Vandsburger Moriel H. , French Brent A. , Kramer Christopher M. , Zhong Xiaodong , Epstein Frederick H.
Published: November 2011

Within cardiomyocytes, endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) are thought to modulate L-type calcium channel (LTCC) function and sarcoplasmic reticulum calcium cycling, respectively. However, divergent results from mostly invasive prior studies suggest more complex roles. To elucidate the roles of nNOS and eNOS in vivo, we applied noninvasive cardiac MRI to study wild-type (WT), eNOS−/−, and nNOS−/− mice. An in vivo index of LTCC flux (LTCCI) was measured at baseline (Bsl), dobutamine (Dob), and dobutamine + carbacholamine (Dob + CCh) using manganese-enhanced MRI. Displacement-encoded MRI assessed contractile function by measuring circumferential strain (Ecc) and systolic (dEcc/dt) and diastolic (dEcc/dtdiastolic) strain rates at Bsl, Dob, and Dob + CCh. Bsl LTCCI was highest in nNOS−/− mice ( P < 0.05 vs. WT and eNOS−/−) and increased only in WT and eNOS−/− mice with Dob ( P < 0.05 vs. Bsl). LTCCI decreased significantly from Dob levels with Dob + CCh in all mice. Contractile function, as assessed by Ecc, was similar in all mice at Bsl. With Dob, Ecc increased significantly in WT and eNOS−/− but not nNOS−/− mice ( P < 0.05 vs. WT and eNOS−/−). With Dob + CCh, Ecc returned to baseline levels in all mice. Systolic blood pressure, measured via tail plethysmography, was highest in eNOS−/− mice ( P < 0.05 vs. WT and nNOS−/−). Mice deficient in nNOS demonstrate increased Bsl LTCC function and an attenuated contractile reserve to Dob, whereas eNOS−/− mice demonstrate normal LTCC and contractile function under all conditions. These results suggest that nNOS, not eNOS, plays the dominant role in modulating Ca2+ cycling in the heart.
How NaCl raises blood pressure: a new paradigm for the pathogenesis of salt-dependent hypertension
Authors: Blaustein Mordecai P. , Leenen Frans H. H. , Chen Ling , Golovina Vera A. , Hamlyn John M. , Pallone Thomas L. , Van Huysse James W. , Zhang Jin , Wier W. Gil
Published: November 2011

Excess dietary salt is a major cause of hypertension. Nevertheless, the specific mechanisms by which salt increases arterial constriction and peripheral vascular resistance, and thereby raises blood pressure (BP), are poorly understood. Here we summarize recent evidence that defines specific molecular links between Na+ and the elevated vascular resistance that directly produces high BP. In this new paradigm, high dietary salt raises cerebrospinal fluid [Na+]. This leads, via the Na+-sensing circumventricular organs of the brain, to increased sympathetic nerve activity (SNA), a major trigger of vasoconstriction. Plasma levels of endogenous ouabain (EO), the Na+ pump ligand, also become elevated. Remarkably, high cerebrospinal fluid [Na+]-evoked, locally secreted (hypothalamic) EO participates in a pathway that mediates the sustained increase in SNA. This hypothalamic signaling chain includes aldosterone, epithelial Na+ channels, EO, ouabain-sensitive α2 Na+ pumps, and angiotensin II (ANG II). The EO increases (e.g.) hypothalamic ANG-II type-1 receptor and NADPH oxidase and decreases neuronal nitric oxide synthase protein expression. The aldosterone-epithelial Na+ channel-EO-α2 Na+ pump-ANG-II pathway modulates the activity of brain cardiovascular control centers that regulate the BP set point and induce sustained changes in SNA. In the periphery, the EO secreted by the adrenal cortex directly enhances vasoconstriction via an EO-α2 Na+ pump-Na+/Ca2+ exchanger-Ca2+ signaling pathway. Circulating EO also activates an EO-α2 Na+ pump-Src kinase signaling cascade. This increases the expression of the Na+/Ca2+ exchanger-transient receptor potential cation channel Ca2+ signaling pathway in arterial smooth muscle but decreases the expression of endothelial vasodilator mechanisms. Additionally, EO is a growth factor and may directly participate in the arterial structural remodeling and lumen narrowing that is frequently observed in established hypertension. These several central and peripheral mechanisms are coordinated, in part by EO, to effect and maintain the salt-induced elevation of BP.
Phasic respiratory modulation of pharyngeal collapsibility via neuromuscular mechanisms in rats
Authors: Cao Ying , McGuire Michelle , Liu Chun , Malhotra Atul , Ling Liming
Published: November 2011

Obstructive sleep apnea patients experience recurrent upper airway (UA) collapse due to decreases in the UA dilator muscle activity during sleep. In contrast, activation of UA dilators reduces pharyngeal critical pressure (Pcrit, an index of pharyngeal collapsibility), suggesting an inverse relationship between pharyngeal collapsibility and dilator activity. Since most UA muscles display phasic respiratory activity, we hypothesized that pharyngeal collapsibility is modulated by respiratory drive via neuromuscular mechanisms. Adult male Sprague-Dawley rats were anesthetized, vagotomized, and ventilated (normocapnia). In one group, integrated genioglossal activity, Pcrit, and maximal airflow (Vmax) were measured at three expiration and five inspiration time points within the breathing cycle. Pcrit was closely and inversely related to phasic genioglossal activity, with the value measured at peak inspiration being the lowest. In other groups, the variables were measured during expiration and peak inspiration, before and after each of five manipulations. Pcrit was 26% more negative (−15.0 ± 1.0 cmH2O, −18.9 ± 1.2 cmH2O; n = 23), Vmax was 7% larger (31.0 ± 1.0 ml/s, 33.2 ± 1.1 ml/s), nasal resistance was 12% bigger [0.49 ± 0.05 cmH2O/(ml/s), 0.59 ± 0.05 cmH2O/(ml/s)], and latency to induced UA closure was 14% longer (55 ± 4 ms, 63 ± 5 ms) during peak inspiration vs. expiration (all P < 0.005). The expiration-inspiration difference in Pcrit was abolished with neuromuscular blockade, hypocapnic apnea, or death but was not reduced by the superior laryngeal nerve transection or altered by tracheal displacement. Collectively, these results suggest that pharyngeal collapsibility is moment-by-moment modulated by respiratory drive and this phasic modulation requires neuromuscular mechanisms, but not the UA negative pressure reflex or tracheal displacement by phasic lung inflation.