bluuebunny/crossref_metadata_2025 huggingface dataset:
Periods of Highly Synchronous, Non‐Reentrant Endocardial Activation Cycles Occur During Long‐Duration Ventricular Fibrillation
Authors: ROBICHAUX ROBERT P. , DOSDALL DEREK J. , OSORIO JOSE , GARNER NICHOLAS W. , LI LI , HUANG JIAN , IDEKER RAYMOND E.
Published: May 2010

Periods of Highly Organized Activation During VF Background: Little is known about long‐duration ventricular fibrillation (LDVF), lasting 1–10 minutes when resuscitation is still possible.

Methods and Results: To determine global left ventricle (LV) endocardial activation during LDVF, 6 canines (9.5 ± 0.8 kg) received a 64‐electrode basket catheter in the LV, a right ventricular (RV) catheter, and a 12‐lead electrocardiogram (ECG). Activation sequences of 15 successive cycles after initiation and after 1, 2, 3, 5, 7, and 10 minutes of LDVF were determined. Early during VF, LV endocardial activation was complex and present throughout most (78.0 ± 9.7%) of each cycle consistent with reentry. After 3–7 minutes of LDVF in 5 animals, endocardial activation became highly synchronized and present for only a small percentage of each cycle (18.2 ± 7.7%), indicating that LV endocardial reentry was no longer present. During this synchronization, activations arose focally in Purkinje fibers and spread as large wavefronts to excite the Purkinje system followed by the subendocardial working myocardium. During this synchronization, the ECG continued to appear irregular, consistent with VF, and LV cycle length (183 ± 29 ms) was significantly different than RV cycle length (144 ± 14 ms) and significantly different than the LV cycle length when synchronization was not present (130 ± 11 ms).

Conclusion: After 3–7 minutes of LDVF, a highly organized, synchronous, focal LV endocardial activation pattern frequently occurs that is not consistent with reentry but is consistent with triggered activity or abnormal automaticity in Purkinje fibers. The ECG continues to appear irregular during this period, partially because of differences in LV and RV cycle lengths. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1266‐1273, November 2010)
Characteristics of Exercise‐Induced Intrapulmonary Arteriovenous Fistula in Patients with Unexplained Exertional Dyspnea
Authors: Kelly Stephanie J. , Singhal Shalabh , Elwing Jean M. , Shizukuda Yukitaka
Published: May 2010

Dynamic appearance of intrapulmonary arteriovenous fistula (AVF) during exercise may be associated with unexplained exertional dyspnea (UED) and can be diagnosed with an agitated saline contrast study during exercise echocardiography. However, the occurrence of AVF during exercise in patients with UED has not been well described. Thus, the frequency of exercise‐induced intrapulmonary AVF in the outpatients with UED was retrospectively analyzed. Thirty‐nine outpatients (age: 53 ± 12, 33 female) with UED underwent symptom‐limited supine bicycle exercise echocardiography. Ten patients (26%) developed exercise‐induced intrapulmonary AVF. Patients with and without AVF showed the similar peak exercise heart rate, systolic blood pressure, and rate‐pressure product. The patients with AVF demonstrated a small but significant decrease in arterial oxygen saturation with exercise as compare to baseline (95.6 ± 2.8% at peak, vs. 97.5 ± 2.5% at baseline, P < 0.05 with a paired Student t‐test). Our study suggests that exercise‐induced intrapulmonary AVF is relatively common in the outpatients with UED and associated with mild exercise desaturation; however, the mechanism of desaturation could not be determined by this study. Further investigation to characterize and determine the clinical significance of AVF is warranted. (Echocardiography 2010;27:908‐913)
The Effect of Cardiac Fibrosis on Left Ventricular Remodeling, Diastolic Function, and N‐Terminal Pro‐B‐Type Natriuretic Peptide Levels in Patients with Nonischemic Dilated Cardiomyopathy
Authors: Karaahmet Tansu , Tigen Kursat , Dundar Cihan , Pala Selcuk , Guler Ahmet , Kilicgedik Alev , Cevik Cihan , Mahmutyazicioglu Kamran , Isiklar Iclal , Basaran Yelda
Published: May 2010

Background: Cardiac fibrosis is common and associated with poor prognosis in patients with heart failure. We investigated the effect of cardiac fibrosis on the left ventricular (LV) diastolic function, functional capacity, LV remodeling, and biochemical parameters in patients with nonischemic dilated cardiomyopathy (NIDC). In addition, we investigated the biochemical and echocardiographic predictors of cardiac fibrosis in this group. Methods and Results: Forty patients with NIDC were enrolled. Cardiac fibrosis was evaluated according to the presence of late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging. Nineteen patients had cardiac fibrosis (Group I) and 21 patients did not have cardiac fibrosis (Group II). LV systolic and diastolic parameters were assessed with conventional and tissue Doppler echocardiography. N‐terminal pro‐B‐type natriuretic peptide (NT‐pro BNP) levels of each patient were recorded. Patients with cardiac fibrosis had impaired diastolic function, higher functional class and NT‐pro BNP levels, and significant LV remodeling than the patients without cardiac fibrosis. A correlation analysis revealed that the cardiac fibrosis severity was associated with functional class, cardiac chamber sizes, NT‐pro BNP levels, diastolic parameters such as E/Se. A linear regression analysis demonstrated that NT‐pro BNP and E/Se were the independent predictors of cardiac fibrosis. Conclusion: Cardiac fibrosis correlates with impaired LV diastolic function and functional capacity, elevated NT‐proBNP levels, and adverse cardiac remodeling in patients with NIDC. Therefore, the assessment of cardiac fibrosis can be useful in the management of these patients. (Echocardiography 2010;27:954‐960)
Validation of Tool Mark Comparisons Obtained Using a Quantitative, Comparative, Statistical Algorithm
Authors: Chumbley L. Scott , Morris Max D. , Kreiser M. James , Fisher Charles , Craft Jeremy , Genalo Lawrence J. , Davis Stephen , Faden David , Kidd Julie
Published: May 2010

Abstract:  A statistical analysis and computational algorithm for comparing pairs of tool marks via profilometry data is described. Empirical validation of the method is established through experiments based on tool marks made at selected fixed angles from 50 sequentially manufactured screwdriver tips. Results obtained from three different comparison scenarios are presented and are in agreement with experiential knowledge possessed by practicing examiners. Further comparisons between scores produced by the algorithm and visual assessments of the same tool mark pairs by professional tool mark examiners in a blind study in general show good agreement between the algorithm and human experts. In specific instances where the algorithm had difficulty in assessing a particular comparison pair, results obtained during the collaborative study with professional examiners suggest ways in which algorithm performance may be improved. It is concluded that the addition of contextual information when inputting data into the algorithm should result in better performance.
The Impact of Racial Metric Variation in the Os Coxae on the Morphological Assessment of Sex*
Authors: Listi Ginesse A.
Published: May 2010

Abstract:  This study examines whether sex determination based on morphological traits in the os coxae is impacted by racial quantitative variation. Nineteen traits were evaluated independently by two observers in 876 os coxae. Chi‐square test was used on a random sample of 400 individuals to assess whether the distribution of correct sex assessment varied for white and black individuals based on each trait individually and all 19 traits collectively, as well as on inter‐observer agreement in correct sex assessment. Results indicate that accuracy of sex assessment varied between white and black individuals in certain individual traits; however, accuracy was not impacted when all traits were considered together. Furthermore, traits that showed significant variation in correct sex assessment between races generally were not related to size, but instead were “discrete.” Finally, analyses of inter‐observer variation suggest that disparities in sex assessment for some traits may be related to differences in trait interpretation between observers rather than morphological dissimilarities between races.
Postmortem Computed Tomography Findings of Upper Airway Obstruction by Food
Authors: Iino Morio , O’Donnell Chris
Published: May 2010

Abstract:  This study is a retrospective analysis of 14 cases with food bolus upper airway obstruction as the defined cause of death where both postmortem computed tomography and autopsy were performed. Three groups were defined by the images i.e., Type 1: foreign body situated between the oral cavity and oropharynx, while the epiglottis sits in normal position, Type 2: foreign body situated in the oropharynx just above the epiglottis pushing it posteriorly and obstructing the airway, and Type 3: foreign body obstructing the laryngeal inlet while pushing the epiglottis anteriorly. At the time of autopsy, foreign bodies were detected by pathologists, occasionally in a different position, presumably being dislodged in the act of organ removal especially for the “Type 1” pattern. CT imaging provides accurate interrogation of upper airway bolus obstruction prior to autopsy.
Isolation and Individualization of Conceptus and Maternal Tissues from Abortions and Placentas for Parentage Testing in Cases of Rape and Abandoned Newborns*
Authors: Johnson Donald J. , Matthies Learden K. , Roberts Katherine A. , Yorker Beatrice Crofts
Published: May 2010

Abstract:  Abortion specimens are often submitted to forensic laboratories as the only piece of physical evidence in rape and incest cases. The recovery of conceptus tissues from this evidence permits the use of paternity testing to evaluate suspects. In cases of abandoned newborns, the recovery of maternal tissue from the placenta allows for the direct comparison of genetic profiles between the suspected mother and the biological mother. We report on the identification and isolation of conceptus tissues from embryonic‐ and fetal‐period abortions, and maternal tissues from delivered placentas, by gross and low‐magnification examination with manual dissection. Hundreds of single‐source samples have been successfully recovered by this method and short tandem repeat typed using standard forensic procedures. We additionally describe extraembryonic tissues that can be recovered and typed in the absence of the embryo proper. We conclude that an expertise and protocols can be developed by forensic laboratories for the routine analysis of this evidence.
Inclusion Probabilities and Dropout
Authors: Curran James M. , Buckleton John
Published: May 2010

Abstract:  Recent discussions on a forensic discussion group highlighted the prevalence of a practice in the application of inclusion probabilities when dropout is possible that is of significant concern. In such cases, there appears to be an unpublished practice of calculation of an inclusion probability only for those loci at which the profile of interest (hereafter the suspect) is fully included among the alleles present in the crime scene sample and to omit those loci at which the suspect has alleles that are not fully represented among the alleles in the mixture. The danger is that this approach may produce apparently strong evidence against a surprisingly large fraction of noncontributors. In this paper, the risk associated with the approach of ignoring loci with discordant alleles is assessed by simulation.
A discrete‐time hazard analysis of the exit of burley tobacco growers in Tennessee, North Carolina, and Virginia
Authors: Tiller Kelly J. , Feleke Shiferaw T. , Starnes Jane H.
Published: May 2010

This article examines the exit and survival dynamics of burley tobacco growers in Tennessee, North Carolina, and Virginia using a discrete‐time hazard logit model. The study also predicts the effects of selected farm and family characteristics on exit hazards, assesses the proportionality of their effects over time and their relative importance in explaining the variation in exit hazards among burley tobacco growers. Results provide the longitudinal progression of the probability of exiting the tobacco industry since the end of the federal tobacco program in 2004, and identify off‐farm participation, percentage of farm receipts from tobacco, tobacco price, educational level, and farm size as the most important determinants of the decision to exit the tobacco industry. Further, the effects of off‐farm participation and farm size on the exit hazards of burley tobacco farms are proportional over time while the effects of the percentage of farm receipts from tobacco and tobacco price are time variant.
Buyers’ perceptions of importance and willingness‐to‐pay for certain attributes of source and production verified bred heifers
Authors: Parcell Joe L. , Franken Jason R.V. , Cox Maria , Patterson David J. , Randle Richard F.
Published: May 2010

This research reports buyers’ perceptions of and willingness‐to‐pay for replacement heifers produced through a rigorous, third‐party verified production protocol. Survey respondents attended and registered to purchase heifers at sanctioned Missouri Show‐Me‐Select Replacement Heifer Program®sales between 1997 and 2002. Responses indicate that pen uniformity, artificially inseminated to calving ease bull, synchronized calving, and heifer size are perceived as important, and their willingness‐to‐pay for these characteristics is economically significant. Though prior research suggests willingness‐to‐pay estimates particularly for inexperienced consumers may be biased, we find little difference between inexperienced and experienced buyers and also little difference from hedonic estimates of heifer characteristics’ value.
Managing increasing environmental risks through agrobiodiversity and agrienvironmental policies
Authors: Baumgärtner Stefan , Quaas Martin F.
Published: May 2010

Agrobiodiversity can provide natural insurance to risk‐averse farmers by reducing the variance of crop yield, and to society at large by reducing the uncertainty in the provision of public‐good ecosystem services, for example, CO2storage. We analyze the choice of agrobiodiversity by risk‐averse farmers who have access to financial insurance, and study the implications for agrienvironmental policy design when on‐farm agrobiodiversity generates a positive risk externality. While increasing environmental risk leads private farmers to increase their level of on‐farm agrobiodiversity, the level of agrobiodiversity in the laissez‐faire equilibrium remains inefficiently low. We show how either one of the two agrienvironmental policy instruments can cure this risk‐related market failure: an ex ante Pigouvian subsidy on on‐farm agrobiodiversity and an ex post payment‐by‐result for the actual provision of public environmental benefits. In the absence of regulation, welfare may increase rather than decrease with increasing environmental risk, if the agroecosystem is characterized by a high natural insurance function, low costs, and large external benefits of agrobiodiversity.
Effects of machinery‐sharing arrangements on farm efficiency: evidence from Sweden
Authors: Larsén Karin
Published: May 2010

The effects of partnerships, in the form of machinery‐sharing arrangements, on farm efficiency are analyzed using data for Swedish crop and livestock farms. Efficiency scores are obtained using Data Envelopment Analysis and the findings suggest that efficiency is, on average, higher among partnership farms compared to nonpartnership farms. Moreover, partnership farms that are characterized by the most extensive form of collaboration, that is, that share all machinery with one or several other farms, display the highest average efficiency. In a two‐stage procedure in which efficiency determinants are analyzed in the second stage, the bootstrap procedures suggested by Simar and Wilson (2007) are applied in addition to the conventionally used Tobit regression. Participation in partnership arrangements is found to have a positive and statistically significant impact on farm efficiency.
Influence of bony defects on implant stability
Authors: Merheb Joe , Coucke Wim , Jacobs Reinhilde , Naert Ignace , Quirynen Marc
Published: May 2010

Introduction: The purpose of this study was to analyze the evolution of implant mechanical stability in different types/sizes of bony defects using both Periotest and Osstell devices as “objective tools.”

Materials and methods: Thirty‐two implants were randomly allocated to one of the four types of bone defects: marginal bone loss, peri‐apical bone defect, constant width dehiscence and constant length dehiscences. Periotest/Osstell measurements were completed before and during staged bone removal (to enlarge defect size).

Results: Significant differences (P<0.05) with initial values were found after a 2 mm marginal bone removal (Osstell/Periotest); for a peri‐apical bone lesion, after removal of 5 mm (Osstell) or 8 mm (Periotest); for a 6‐mm‐long dehiscence, after removal up to 180° of the implant perimeter (Osstell/Periotest); for a 3‐mm‐wide dehiscence, after removal of 10 mm (Osstell) or 6 mm (Periotest).

Conclusion: Periotest and Osstell are in general not very sensitive in the identification of peri‐implant bone destruction, except for marginal bone loss.

To cite this article:
 Merheb J, Coucke W, Jacobs R, Naert I, Quirynen M. Influence of bony defects on implant stability. Clin. Oral Impl. Res. 21, 2010; 919–923. doi: 10.1111/j.1600‐0501.2010.01932.x
Lateral ridge augmentation using equine‐ and bovine‐derived cancellous bone blocks: a feasibility study in dogs
Authors: Schwarz Frank , Ferrari Daniel , Balic Ela , Buser Daniel , Becker Jürgen , Sager Martin
Published: May 2010

Objectives: The aim of the present study was to histologically evaluate and compare a new prototype collagen type I/III‐containing equine‐ (EB) and a bovine‐ (BB) derived cancellous bone block in a dog model.

Materials and methods: Four standardized box‐shaped defects were bilaterally created at the buccal aspect of the alveolar ridge in the lower jaws of five beagle dogs and randomly allocated to either EB or BB. Each experimental site was covered by a native (non‐crosslinked) collagen membrane and left to heal in a submerged position for 12 weeks. Dissected blocks were processed for semi‐/and quantitative analyses.

Results: Both groups had no adverse clinical or histopathological events (i.e. inflammatory/foreign body reactions). BB specimens revealed no signs of biodegradation and were commonly embedded in a fibrous connective tissue. New bone formation and bony graft integration were minimal. In contrast, EB specimens were characterized by a significantly increased cell (i.e. osteoclasts and multinucleated giant cells)‐mediated degradation of the graft material (P<0.001). The amount and extent of bone ingrowth was consistently higher in all EB specimens, but failed to reach statistical significance in comparison with the BB group (P>0.05).

Conclusions: It was concluded that the application of EB may not be associated with an improved bone formation than BB.

To cite this article:
 Schwarz F, Ferrari D, Balic E, Buser D, Becker J, Sager M. Lateral ridge augmentation using equine‐ and bovine‐derived cancellous bone blocks: a feasibility study in dogs. Clin. Oral Impl. Res. 21, 2010; 904–912. doi: 10.1111/j.1600‐0501.2010.01951.x
Periodontal wound healing/regeneration following the application of rhGDF‐5 in a β‐TCP/PLGA carrier in critical‐size supra‐alveolar periodontal defects in dogs
Authors: Kwon David H. , Bisch Frederick C. , Herold Robert W. , Pompe Cornelius , Bastone Patrizia , Rodriguez Nancy A. , Susin Cristiano , Wikesjö Ulf ME
Published: May 2010

Kwon DH, Bisch FC, Herold RW, Pompe C, Bastone P, Rodriguez NA, Susin C, Wikesjö UM. Periodontal wound healing/regeneration following application of rhGDF‐5 in a β‐TCP/PLGA carrier in critical‐size supra‐alveolar periodontal defects in dogs. J Clin Periodontol 2010; 37: 667–674. doi: 10.1111/j.1600‐051X.2010.01569.x.

Aim: The objective of this study was to evaluate the effect of a novel recombinant human GDF‐5 (rhGDF‐5) construct intended for onlay and inlay indications on periodontal wound healing/regeneration.

Methods: Contralateral, surgically created, critical‐size, 6‐mm, supra‐alveolar periodontal defects in five adult Hound Labrador mongrel dogs received rhGDF‐5 coated onto β‐tricalcium phosphate (β‐TCP) particles and immersed in a bioresorbable poly(lactic‐co‐glycolic acid) (PLGA) composite or the β‐TCP/PLGA carrier alone (control). The rhGDF‐5 and control constructs were moulded around the teeth and allowed to set. The gingival flaps were then advanced; flap margins were adapted 3–4 mm coronal to the teeth and sutured. The animals were euthanized at 8 weeks post‐surgery when block biopsies were collected for histometric analysis.

Results: Healing was generally uneventful. A few sites exhibited minor exposures. Three control sites and one rhGDF‐5 site (in separate animals) experienced more extensive wound dehiscencies. The rhGDF‐5 and control constructs were easy to apply and exhibited adequate structural integrity to support the mucoperiosteal flaps in this challenging onlay model. Limited residual β‐TCP particles were observed at 8 weeks for both rhGDF‐5/β‐TCP/PLGA and β‐TCP/PLGA control sites. The rhGDF‐5/β‐TCP/PLGA sites showed significantly greater cementum (2.34 ± 0.44 versus 1.13 ± 0.25 mm, p=0.02) and bone (2.92 ± 0.66 versus 1.21 ± 0.30 mm, p=0.02) formation compared with the carrier control. Limited ankylosis was observed in four of five rhGDF‐5/β‐TCP/PLGA sites but not in control sites.

Conclusions: Within the limitations of this study, the results suggest that rhGDF‐5 is a promising candidate technology in support of periodontal wound healing/regeneration. Carrier and rhGDF‐5 dose optimization are necessary before further advancement of the technology towards clinical evaluation.
Comparing methods for measuring the rate of spread of invading populations
Authors: Gilbert Marius , Liebhold Andrew
Published: May 2010

Measuring rates of spread during biological invasions is important for predicting where and when invading organisms will spread in the future as well as for quantifying the influence of environmental conditions on invasion speed. While several methods have been proposed in the literature to measure spread rates, a comprehensive comparison of their accuracy when applied to empirical data would be problematic because true rates of spread are never known. This study compares the performances of several spread rate measurement methods using a set of simulated invasions with known theoretical spread rates over a hypothetical region where a set of sampling points are distributed. We vary the density and distribution (aggregative, random, and regular) of the sampling points as well as the shape of the invaded area and then compare how different spread rate measurement methods accommodate these varying conditions. We find that the method of regressing distance to the point of origin of the invasion as a function of time of first detection provides the most reliable method over adverse conditions (low sampling density, aggregated distribution of sampling points, irregular invaded area). The boundary displacement method appears to be a useful complementary method when sampling density is sufficiently high, as it provides an instantaneous measure of spread rate, and does not require long time series of data.
Reproducibility of the multi‐component aspect of species diversity across different areas and scales: towards the constitution of a shortlist of complementary indices for monitoring fish diversity?
Authors: Gaertner Jean‐Claude , Mérigot Bastien , Rélini Giulio , Bertrand Jacques A. , Mazouni Nabila , Politou Chrissi‐Yianna , Gil de Sola Luis , Kallianiotis Argyris , Carpentieri Paolo , Murenu Matteo , Durbec Jean‐Pierre , Vrgoc Nedo , Ungaro Nicola
Published: May 2010

Recent theoretical and field studies conducted in both terrestrial and marine ecosystems have suggested that diversity could be a more complex and multi‐component concept than previously thought. However, it is still poorly understood to what extent the information provided by the various indices is complementary with regard to diversity, and to what extent this complementarity is reproducible in different situations or at different scales of observation. In the present work, we have analysed the reproducibility of the empirical relationships between 11 diversity indices related to four major aspects (components) of species diversity (species richness, rarity, evenness and species taxonomy) in order to determine whether there is a general pattern of redundancy or complementarity in diversity measures that holds across years, areas and spatial scales. We have applied this approach to groundfish diversity through the analysis of 2404 trawl hauls collected during the first large‐scale annual surveys carried out using a single sampling design throughout the northern Mediterranean Sea (ranging from 36.3 to 45.7°N, and 5.3°W to 28°E). Whatever the years, areas and scales studied, we found a strong reproducibility in the number and the nature of the main complementary components of diversity. The whole set of diversity indices considered may be roughly split into 6 complementary groups of descriptors. This result highlights that, in contrast to what is still the usual practice, monitoring diversity should not be based on only one or two of the most widely used components, even at large scale. Finally, in a context where developing tools for monitoring diversity is considered as a high priority worldwide, the strong reproducibility of the relationships between diversity indices we observed offers a basis for discussion of the feasibility and relevance of proposing a general shortlist of indices for monitoring diversity at different management scales.
Differential response to abiotic conditions and predation risk rather than competition avoidance determine breeding site selection by anurans
Authors: Indermaur Lukas , Schaub Michael , Jokela Jukka , Tockner Klement , Schmidt Benedikt R.
Published: May 2010

Co‐existence of species has been a central debate in ecology for decades but the mechanisms that allow co‐existence are still heatedly disputed. The main paradigms have shifted among the importance of competition, predation and abiotic conditions as determinants of community structure. Differential habitat selection is considered to reduce competition and hence allow co‐existence. Our goal was to test hypotheses regarding how breeding site use of a population that was patchily distributed on a dynamic floodplain may facilitate coexistence: 1) do species co‐occur randomly or do they occur more or less often than expected by chance? 2) Do species use the same habitat types in equal proportions or do they use them differentially? 3) If they use habitat types differentially, is this differential use related to abiotic and biotic conditions? 4) Does interspecific competition predict breeding site use or do abiotic conditions and predation risk better predict habitat use? We collected presence/absence (i.e. detection/nondetection) data of egg clutches and larvae of four pond‐breeding anuran species during a two year study at a total of 353 ponds. We used site occupancy models and model averaging techniques to predict breeding site selection in relation to habitat types, abiotic and biotic factors. These parameters were corrected for imperfect detection of species. The rates of co‐occurrence were consistently higher than expected by chance. Species differed in the use of the main habitat types. Habitat types that were used by multiple species were used in a species‐specific manner in relation to both abiotic conditions and predation risk. Species preferred ponds where other species and fish were present. Although niche differentiation in breeding site selection is evident, our results do not support the pervasive role of competition avoidance in governing current breeding site selection. We conclude that differential habitat use and differences in response to abiotic conditions and predation risk can override competitive interactions, thereby facilitating local co‐existence and high species diversity.
Determinants of tapeworm species richness in elasmobranch fishes: untangling environmental and phylogenetic influences
Authors: Randhawa Haseeb S. , Poulin Robert
Published: May 2010

Parasite species richness is a fundamental characteristic of host species and varies substantially among host communities. Hypotheses aiming to explain observed patterns of richness are numerous, and none is universal. In this study, we use tapeworm parasites of elasmobranch fishes to examine the phylogenetic and environmental influences on the variation in species richness for this specific system. Tapeworms are the most diverse group of helminths to infect elasmobranchs. Elasmobranchs are cosmopolitan in distribution and their tapeworm parasites are remarkably host specific; therefore, making this an ideal system in which to examine global patterns in species diversity. Here, we 1) quantify the tapeworm richness in elasmobranch fishes, 2) identify the host features correlated with tapeworm richness, and 3) determine whether tapeworm richness follows a latitudinal gradient. The individual and combined effects of host size, factors associated with water temperatures (influenced by latitude and depth), host habitat, and type of elasmobranch (shark or batoid) on measures of species diversity were assessed using general linear models. These analyses included tapeworm host records for 317 different elasmobranch species (124 species were included in our analyses) and were conducted with and without taking into account phylogenetic relationships between host species. Since sharks and batoids differ substantially in body form, analyses were repeated for each host subset. On average, batoids harboured significantly more tapeworm species than shark hosts. Tapeworm richness in sharks was influenced by median depth, whereas no predictor variable included in our models could adequately account for interspecific variation in tapeworm richness in batoid hosts. The taxonomic diversity of tapeworm assemblages of sharks and batoids was influenced by median depth and median latitude, respectively. When the influence of host phylogeny is accounted for, larger hosts harbour a greater tapeworm richness, whereas hosts exploiting wider latitudinal ranges harbour more taxonomically distinct tapeworm assemblages. Species richness and taxonomic diversity of tapeworm assemblages in elasmobranch fishes are influenced by different evolutionary pressures, including host phylogenetic relationships, space constraints and geographical area. Our results suggest that ca 3600 tapeworm species have yet to be described from elasmobranch fishes.
The relationship between geographic range size and life history traits: is biogeographic history uncovered? A test using the Iberian butterflies
Authors: Garcia‐Barros Enrique , Romo Benito Helena
Published: May 2010

The geographic range of a species is influenced by past phylogenetic and biogeographic patterns. However, other historical interactions, including the interplay between life history and geography, are also likely involved. Therefore, the range size of a species can be explained on the basis of niche‐breadth or dispersal related hypotheses, and previous work on European butterflies suggests that both, under the respective guise of ecological specialisation and colonising ability may apply. In the present study, data from 205 species of butterflies from the Iberian peninsula were processed through multiple regression analyses to test for correlations between geographic range size, life history traits and geographic features of the species distribution types. In addition, the percentage of variance explained by the subsets of variables analyzed in the study, with and without control for phylogenetic effects was tested. Despite a complex pattern of bivariate correlations, we found that larval polyphagy was the single best correlate of range size, followed by dispersal. Models that combined both life history traits and geographic characteristics performed better than models generated independently. The combined variables explained at least 39% of the variance. Bivariate correlations between range size and body size, migratory habits or egg size primarily reflected taxonomic patterning and reciprocal correlations with larval diet breadth and adult phenology. Therefore, aspects of niche breadth i.e. potential larval diet breadth emerged as the most influential determinants of range size. However, the relationships between these types of ecological traits and biogeographic history must still be considered when associations between life history and range size are of interest.
High‐density areas for harbor porpoises (Phocoena phocoena) identified by satellite tracking
Authors: Sveegaard Signe , Teilmann Jonas , Tougaard Jakob , Dietz Rune , Mouritsen Kim N. , Desportes Geneviève , Siebert Ursula
Published: May 2010

Abstract

The population status of harbor porpoises has been of concern for several years, and the establishment of Marine Protected Areas (MPAs) has been suggested as a method to protect the harbor porpoise (Phocoena phocoena, Linneaus 1758) and other small cetaceans. In order to designate MPAs, high‐density areas for the species must be identified. Spatial distribution of small cetaceans is usually assessed from ship or aerial surveys. As a potentially more accurate alternative, this study examined the movements and area preferences of 64 harbor porpoises, satellite tagged between 1997 and 2007, in order to determine the distribution in the North Sea, the western Baltic, and the waters in between. Results show that harbor porpoises are not evenly distributed, but congregate in nine high‐density areas within the study area. Several of these areas are subject to significant seasonal variation. The study found no differences in the home range size of males and females, but immature harbor porpoises have larger home ranges than mature porpoises. The use of satellite telemetry for identifying areas of high harbor porpoise density can be of key importance when designating MPAs.
Estimated field metabolic rates and prey requirements of resident killer whales
Authors: Noren Dawn P.
Published: May 2010

Abstract

Killer whales are large animals that often feed in groups and thus have the potential to deplete prey populations. Determining predator energy requirements is essential to assessing whether prey availability is sufficient. This is important because one risk factor facing the endangered Southern Resident killer whale distinct population segment is limited prey availability. Body mass, field metabolic rate (FMR), and daily prey energy requirements (DPERs) were estimated for each individual in the population. FMRs were calculated from body mass, assuming they range from five to six times Kleiber‐predicted basal metabolic rates. FMRs of adults were also calculated from resident killer whale activity budgets and the metabolic cost of swimming at speeds associated with daily activities. These two methods yielded similar results. Total FMRs varied by age and sex, which is partly due to the long developmental period and sexual dimorphism in killer whales. FMRs for males (465–4,434 kg) ranged from 35,048 to 228,216 kcal/d while FMRs for females (465–3,338 kg) ranged from 35,048 to 184,444 kcal/d. DPERs were calculated from FMRs assuming a standard digestive efficiency. Corresponding DPERs ranged from 41,376 to 269,458 kcal/d and 41,376 to 217,775 kcal/d, respectively.
Potential of Several Protein Sources as Fish Meal Substitutes in Diets for Large Yellow Croaker, Pseudosciaena crocea R
Authors: Li Jing , Zhang Lu , Mai Kangsen , Ai Qinghui , Zhang Chunxiao , Li Huitao , Duan Qingyuan , Ma Hongming , Zhang Lu , Zheng Shixuan
Published: May 2010

A feeding experiment was conducted to evaluate the potential of replacing fish meal (FM, Diet 1) with soybean meal (SBM, Diet 2), meat and bone meal (MBM, Diet 3), poultry by‐product meal (PBM, Diet 4), and peanut meal (PM, Diet 5) in practical diets of juvenile large yellow croaker, Pseudosciaena crocea. Five isonitrogenous and isoenergetic diets (43% crude protein and 20 kJ/g gross energy on dry matter basis) were formulated. Diet containing FM as the main protein source was used as a control (Diet 1). Diets 2–5 had 30% of the FM protein replaced with SBM, MBM, PBM, or PM protein. Each diet was randomly assigned to triplicate groups of 25 fish per cage (initial body weight 23.3 ± 0.96 g). Fish were maintained in sea floating cages (1.5 × 1.5 × 2.0 m), water temperature ranged from 27 to 30 C, salinity from 25 to 28‰ and dissolved oxygen content was more than 7 mg/L. Fish were hand‐fed twice daily to apparently satiation for 8 wk. Fish fed Diets 1–4 showed no significant difference in survival, weight gain (WG) and specific growth rate (SGR), while fish fed Diet 5 showed significant inferior WG and SGR (P < 0.01). Carcass crude protein and crude lipid of the fish fed Diet 5 were significantly lower than those of the fish fed the other diets (P < 0.05). Carcass lysine content of the of fish fed Diet 5 showed slight, yet significantly decrease (P < 0.05), compared with those of the fish fed Diets 1–4, while other essential amino acids (EAAs) content showed no significant differences among the different treatments. Results of the present study indicate that about 30% of FM protein can be replaced by SBM, MBM, or PBM protein in large yellow croaker diets without adversely effecting growth.
Role of the Protein Cavity in Phytochrome Chromoprotein Assembly and Double‐bond Isomerization: A Comparison with Model Compounds
Authors: Rohmer Thierry , Lang Christina , Gärtner Wolfgang , Hughes Jon , Matysik Jörg
Published: May 2010

Difference patterns of 13C NMR chemicals shifts for the protonation of a free model compound in organic solution, as reported in the literature (M. Stanek, K. Grubmayr [1998] Chem. Eur. J.4, 1653–1659), were compared with changes in the protonation state occurring during holophytochrome assembly from phycocyanobilin (PCB) and the apoprotein. Both processes induce identical changes in the NMR signals, indicating that the assembly process is linked to protonation of the chromophore, yielding a cationic cofactor in a heterogeneous, quasi‐liquid protein environment. The identity of both difference patterns implies that the protonation of a model compound in solution causes a partial stretching of the geometry of the macrocycle as found in the protein. In fact, the similarity of the difference pattern within the bilin family for identical chemical transformations represents a basis for future theoretical analysis. On the other hand, the change of the 13C NMR chemical shift pattern upon the Pr → Pfr photoisomerization is very different to that of the free model compound upon ZZZ → ZZE photoisomerization. Hence, the character of the double‐bond isomerization in phytochrome is essentially different from that of a classical photoinduced double‐bond isomerization, emphasizing the role of the protein environment in the modulation of this light‐induced process.
Prostaglandin‐E2 is produced by adult human epidermal melanocytes in response to UVB in a melanogenesis‐independent manner
Authors: Gledhill Karl , Rhodes Lesley E. , Brownrigg Margaret , Haylett Ann K. , Masoodi Mojgan , Thody Anthony J. , Nicolaou Anna , Tobin Desmond J.
Published: May 2010

Excessive ultraviolet radiation (UVR) exposure induces erythema, mediated in part by prostaglandin‐E2 (PGE2). While keratinocytes are a major PGE2 source, epidermal melanocytes (EM) also express PGE2‐production machinery. It is unclear whether EM‐produced PGE2 contributes to UVR‐induced skin inflammation, and whether this is correlated with melanogenesis. Epidermal melanocytes were cultured from skin phototype‐1 and ‐4 donors, followed by assessment of PGE2 production and melanogenesis. Epidermal melanocytes expressed cytoplasmic phospholipase‐A2, cyclooxygenase‐1, cytoplasmic prostaglandin‐E synthase and microsomal prostaglandin‐E synthase‐1, ‐2. Epidermal melanocytes produced PGE2 under basal conditions, which increased further after arachidonic acid stimulation. Epidermal melanocytes expressed cyclooxygenase‐2 (COX‐2) mRNA and a selective COX‐2 inhibitor (NS‐398) reduced PGE2 production. Ultraviolet B‐induced PGE2 production was positively correlated with skin phototype‐1, despite variability between individual EM donors. By contrast, there was no correlation between PGE2 production by EM and their melanogenic status. Thus, EM may contribute to UVR‐induced erythema, with role of donor skin phototype more important than their melanogenic status.
A cadaver study comparing two approaches to perform a maxillary nerve block in the horse
Authors: BARDELL D. , IFF I. , MOSING M.
Published: May 2010

Reasons for performing study: Anaesthesia of the maxillary nerve of the horse has been described using several approaches, but sparse data exist to evaluate the accuracy of these methods.

Objectives: This study compared 2 previously described approaches to the maxillary nerve to assess their relative accuracies.

Methods: Thirty severed heads from horse cadavers were arranged to approximate the position of a live horse. Methylene blue (0.25 or 0.1 ml) was injected using a 19 gauge 90 mm spinal needle by one of 2 approaches, the method used being randomly allocated in each instance. Method ANG: angulated needle insertion on the ventral border of the zygomatic process of the temporal bone and directed rostromedially. Method PER: needle inserted perpendicular to the skin surface, ventral to the zygomatic process of the malar bone, level with the temporal canthus of the eye. Accuracy of dye deposition was assessed following dissection. Placement was categorised as ‘full hit’ (complete nerve coverage or dye deposition centred on nerve), ‘partial hit’ (partial nerve discolouration but dye not centred on nerve) or ‘miss’ (no nerve discolouration). Deposition of dye relative to the nerve and whether injection was performed on the left or right side of the head was recorded. A Chi‐squared test was performed to examine the relationship between the 2 methods.

Results: Method ANG was performed 31 times, Method PER 28 times. Full hits were 10/31 (32%) vs. 9/28 (32%), partial hits 15/31 (49%) vs. 14/28 (50%) and misses 6/31 (19%) vs. 5/28 (18%) (Methods ANG vs. PER, respectively). Results were not statistically significantly different between the methods. Dye was deposited in the deep facial vein once by each method. Bone was contacted consistently with Method PER and 8/31 times with Method ANG.

Conclusion and clinical relevance: Both methods appeared equivalent in terms of accuracy. Aspiration should always precede injection.
Targeting Myeloid Leukemia Stem Cells
Authors: Jordan Craig T.
Published: May 2010

Recently described cell surface molecules that are selectively
expressed on leukemia stem cells may pave the way for antibody-based
diagnostics or therapeutics.
Function Follows Form: Defining Mammary Stem Cells
Authors: Vivanco María dM
Published: May 2010

Functional isolation of normal mammary stem cells offers molecular insights into these cells and their cancerous counterparts.
Stopping Cancer in Its Tracks
Authors: Cheng Elaine
Published: May 2010

Combination therapy with TRAIL and all-
trans
-retinyl acetate prevents the progression of premalignant intestinal polyps into colon cancer.
Fasting and recovery from exercise
Authors: Burke Louise
Published: May 2010

Recovery after strenuous exercise involves processes that are dependent on fluid and food intake. Current sports nutrition guidelines provide recommendations for the quantity and timing of consumption of nutrients to optimise recovery issues such as refuelling, rehydration and protein synthesis for repair and adaptation. Recovery of immune and antioxidant systems is important but less well documented. In some cases, there is little effective recovery until nutrients are supplied, while in others, the stimulus for recovery is strongest in the period immediately after exercise. Lack of appropriate nutritional support will reduce adaption to exercise and impair preparation for future bouts. Ramadan represents a special case of intermittent fasting undertaken by many athletes during periods of training as well as important competitive events. The avoidance of fluid and food intake from sunrise to sundown involves prolonged periods without intake of nutrients, inflexibility with the timing of eating and drinking over the day and around an exercise session, and changes to usual dietary choices due to the special foods involved with various rituals. These outcomes will all challenge the athlete's ability to recover optimally between exercise sessions undertaken during the fast or from day to day.
Airway hyperresponsiveness to methacholine, adenosine 5-monophosphate, mannitol, eucapnic voluntary hyperpnoea and field exercise challenge in elite cross-country skiers
Authors: Sue-Chu Malcolm , Brannan John D , Anderson Sandra D , Chew Nora , Bjermer Leif
Published: May 2010

Background

Methacholine hyperresponsiveness is prevalent in elite athletes. Comparative studies have hitherto been limited to methacholine, eucapnic voluntary hyperpnoea and exercise. This study investigated airway responsiveness to these stimuli as well as to adenosine 5′-monophosphate (AMP) and mannitol, in 58 cross-country ski athletes.

Methods

Exhaled nitric oxide concentration (FENO), spirometry and bronchial challenge in random order with methacholine, AMP and mannitol were consecutively performed on three study days in the autumn. Specific IgE to eight aeroallergens and a self-completed questionnaire about respiratory symptoms, allergy and asthmatic medication were also performed on day 1. Eucapnic voluntary hyperventilation (EVH) and field exercise tests were randomly performed in 33 of the skiers on two study days in the following winter.

Results

Of 25 (43%) skiers with airway hyperresponsiveness (AHR), 23, five and three skiers were hyperresponsive to methacholine, AMP and mannitol, respectively. Methacholine hyperresponsiveness was more prevalent in subjects without asthma-like symptoms. The FENO was not significantly different in skiers with and without methacholine hyperresponsiveness. Four of 14 skiers with and four of 19 skiers without methacholine hyperresponsiveness were hyperresponsive to EVH or exercise challenge. AHR to any stimulus was present in 16 asymptomatic and nine symptomatic skiers. Asthma-like symptoms were not correlated with AHR to any stimulus.

Conclusions

Methacholine hyperresponsiveness is more common in asymptomatic skiers and is a poor predictor of hyperresponsiveness to mannitol and hyperpnoea. The low prevalence of hyperresponsiveness to indirect stimuli may suggest differences in the pathogenesis of methacholine hyperresponsiveness in elite skiers and non-athletes.
Types of Florin rings, distributional patterns of epicuticular wax, and their relationships in the genus Pinus
Authors: Yoshie Fumio , Sara Akira
Published: May 2010

The shape of Florin rings and the distributional patterns of epicuticular wax of 51 species, including three varieties, in the genus Pinus were observed and classified with a scanning electron microscope. Six types of Florin rings and three types of wax distribution were observed. Florin ring structures and wax distribution correspond to subgenera. The restriction of the epicuticular waxes to the needle surface on which stomatal complexes occur suggests that the wax originates in association with the stomatal complex. In the subgenus Pinus, the Florin ring with a small opening size had little wax in the epistomatal chamber; the Florin ring with a large opening size had large amounts of wax. This suggests that the amount of wax in the epistomatal chamber and the opening size of the Florin ring are correlated with gas diffusion. Common thin, fibrillar wax, rare thick, winding wax, and occasional amorphous wax were observed. The relationships among the types of Florin rings are further discussed from the viewpoint of a developmental process.