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Selected AbstractsAngler awareness of aquatic nuisance species and potential transport mechanismsFISHERIES MANAGEMENT & ECOLOGY, Issue 6 2009K. K. GATES Abstract, The role anglers play in transporting aquatic nuisance species (ANS) is important in managing infestations and preventing introductions. The objectives of this study were to: (1) quantify angler movement patterns in southwestern Montana, ANS awareness and equipment cleaning practices; and (2) quantify the amount of soil transported on boots and waders. Mean distance travelled by residents from their home to the survey site was 115 km (±17, 95% CI). Mean distance travelled by non-residents was 1738 km (±74). Fifty-one percent of residents and 49% of non-residents reported occasionally, rarely or never cleaning their boots and waders between uses. Mean weight of soil carried on one boot leg was 8.39 g (±1.50). Movement and equipment cleaning practices of anglers in southwestern Montana suggest that future control of ANS dispersal may require restricting the use of felt-soled wading boots, requiring river-specific wading equipment or providing cleaning stations and requiring their use. [source] Exact Location of the Branching Bundle in the Living HeartPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2009MASAMITSU ADACHI M.D., Ph.D. Aims: The His bundle electrogram is believed to reflect the exact location of the His bundle. However, the distinction between distal His bundle potential and proximal right bundle branch potential is challenging. The aim of this study was to pinpoint the location of the branching point of the His bundle, and to compare that site with the site of recording of the largest His bundle electrogram (LH) during sinus rhythm. Methods: We hypothesized that the site of earliest His activation (EH) during retrograde conduction via the left bundle branch is the branching point. We studied 15 nonconsecutive patients (mean age = 40 ± 22 years; eight men). We performed a programmed stimulation from right ventricular apex until retrograde right bundle branch block appeared. At that point we measured (1) the distance between antegrade LH site and retrograde EH site and (2) the atrial-to-ventricular amplitude ratio (A/V ratio) at both sites. Results: EH was recorded at the proximal electrode of the His bundle catheter in all patients. Mean distance between EH and LH was 9.8 ± 2.5 mm. The mean A/V ratios at the EH site and the LH site were 1.01 ± 0.42 and 0.08 ± 0.06, respectively. Discussion: This study showed that the EH site is located approximately 10-mm proximal to the LH site. The mean A/V ratio at the EH site during sinus rhythm is approximately 1.0. These observations suggest that the majority of His potentials reflect proximal right bundle activation. Before delivering radiofrequency energy in the para-Hisian area, attention should be paid to the presence of a His potential and to the A/V ratio, rather to the amplitude of the His electrogram. [source] Interstitial Cajal-like cells in rat mesentery: an ultrastructural and immunohistochemical approachJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2008M. E. Hinescu Abstract Interstitial Cajal-like Cells (ICLC) were recently recognized in a plethora of non-digestive organs. Here, we describe a cell type of rat mesentery sharing ultrastructural and immunohistochemical features with ICLC. Mesenteric ICLC were demonstrated by transmission electron microscopy (TEM) and further tested by light microscope immunohistochemistry. The cell described here fulfils the TEM diagnostic criteria accepted for ICLC: location in the connective interstitium; close vicinity to nerves, capillaries and other interstitial cells; characteristic long, moniliform cell processes; specialized cell-to-cell junctions; caveolae; mitochondria at 5,10% of cytoplasmic volume; rough endoplasmic reticulum at about 1,2%; intermediate and thin filaments, microtubules; undetectable thick filaments. The processes of this mesenteric ICLC were particularly long, with a mean length of 24.91 ,m (10.27,50.83 ,m), and a convolution index of 2.32 (1.37,3.63) was calculated in order to measure their potential length. Mean distances versus main target cells of ICLC,nerve bundles, vessels, adipocytes and macrophages,were 110.69, 115.80, 205.07 and 34.65 nm, respectively. We also tested the expression of CD117/c-kit, CD34, vimentin, ,-smooth muscle actin, nestin, NK-1, tryptase and chymase and the antigenic profile of the mesenteric ICLC was comparable if not identical with that recently observed in ICLC from other extra-digestive tissues. Due to the peculiar aspect of the mesenteric ICLC processes it can be hypothesized that these cells form a three-dimensional network within the mesentery that is at the same time resistant and deformable following stretches consequent to intestine movements, mainly avoiding blood vessels closure or controlling blood vessels rheology. It remains, however, to be established if and how such cells are connected with the archetypal enteric ICC. [source] Effects of Habitat Fragmentation on Effective Dispersal of Florida Scrub-JaysCONSERVATION BIOLOGY, Issue 4 2010AURÉLIE COULON Aphelocoma c,rulescens; dispersión; flujo génico; fragmentación Abstract:,Studies comparing dispersal in fragmented versus unfragmented landscapes show that habitat fragmentation alters the dispersal behavior of many species. We used two complementary approaches to explore Florida Scrub-Jay (Aphelocoma c,rulescens) dispersal in relation to landscape fragmentation. First, we compared dispersal distances of color-marked individuals in intensively monitored continuous and fragmented landscapes. Second, we estimated effective dispersal relative to the degree of fragmentation (as inferred from two landscape indexes: proportion of study site covered with Florida Scrub-Jay habitat and mean distance to nearest habitat patch within each study site) by comparing genetic isolation-by-distance regressions among 13 study sites having a range of landscape structures. Among color-banded individuals, dispersal distances were greater in fragmented versus continuous landscapes, a result consistent with other studies. Nevertheless, genetic analyses revealed that effective dispersal decreases as the proportion of habitat in the landscape decreases. These results suggest that although individual Florida Scrub-Jays may disperse farther as fragmentation increases, those that do so are less successful as breeders than those that disperse short distances. Our study highlights the importance of combining observational data with genetic inferences when evaluating the complex biological and life-history implications of dispersal. Resumen:,Estudios que comparan la dispersión en paisajes fragmentados versus no fragmentados muestran que la fragmentación del hábitat altera la conducta de dispersión de muchas especies. Utilizamos dos métodos complementarios para explorar la dispersión de Aphelocoma c,rulescens en relación con la fragmentación del paisaje. Primero, comparamos las distancias de dispersión de individuos marcados con color en paisajes continuos y fragmentados monitoreados intensivamente. Segundo, estimamos la dispersión efectiva en relación con el grado de fragmentación (inferida a partir de dos índices del paisaje: proporción del sitio de estudio cubierta con hábitat para A. c,rulescens y la distancia promedio al parche más cercano en cada sitio de estudio) mediante la comparación de regresiones de aislamiento genético por distancia entre 13 sitios de estudio con una gama de estructuras de paisaje. Entre los individuos marcados con color, las distancias de dispersión fueron mayores en los paisajes fragmentados versus los continuos, un resultado consistente con otros estudios. Sin embargo, los análisis genéticos revelaron que la dispersión efectiva decrece a medida que decrece la proporción de hábitat en el paisaje. Estos resultados sugieren que aunque individuos de A. c,rulescens pueden dispersarse más lejos a medida que incrementa la fragmentación, aquellos que lo hacen son reproductores menos exitosos que los que se dispersan a corta distancia. Nuestro estudio resalta la importancia de combinar datos observacionales con inferencias genéticas cuando se evalúan las complejas implicaciones de la dispersión sobre la biología y la historia natural. [source] Spatio-temporal shifts in gradients of habitat quality for an opportunistic avian predatorECOGRAPHY, Issue 2 2003Fabrizio Sergio We used the conceptual framework of the theory of natural selection to study breeding habitat preferences by an opportunistic avian predator, the black kite Milvus migrans. In Europe, black kite populations are mostly found near large networks of aquatic habitats, usually considered optimal for foraging and breeding. We hypothesized that proximity to wetlands could vary among individuals and affect their fitness, and thus be subject to natural selection. We tested the hypothesis first on a population on Lake Lugano (Italian pre-Alps) which has been monitored for nine years, and then on seven other populations, each studied for four,five years, located along a continuum of habitat from large water bodies to scarce aquatic habitat of any kind. In the Lake Lugano population, black kite abundance was negatively related to distance to the lake in all the nine years of study, consistent with long-term natural selection. There was evidence of ongoing directional selection on strategic nest location in three of the years, and evidence of stabilizing selection in two years. In eight of the nine years the trend was for a linear increase in fitness with increasing proximity to the lake. At the population level, results were consistent with adaptive habitat choice in relation to the previous year's spatial variation in fitness: higher associations between fitness and distance to the lake (i.e. higher selection gradients) resulted in higher density variations in the following year, in turn related to the availability of fish, the main local prey. The progressive decline of inland pairs and increase in the density of lakeshore pairs caused a directional long-term trend of declining mean distance to the lake. Breeding near aquatic habitats was associated with higher foraging success, and higher frequency and biomass of prey deliveries to offspring. There was weak evidence of selection in other populations. The inland-wetland gradient of habitat quality may have been affected by predation risk, as estimated by density of a major predator of adults and nestlings, the eagle owl Bubo bubo. Behavioral decisions at the level of the individual probably translated into population effects on density and distribution at various spatial scales. Populations in optimal habitats showed higher density and produced six times as many young per unit space as those in sub-optimal habitats. [source] Aquatic macroinvertebrates in the altes land, an intensely used orchard region in Germany: Correlation between community structure and potential for pesticide exposureENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2006Christoph Schäfers Abstract To assess the impact of pesticides on aquatic organisms under realistic worst-case conditions, a macroinvertebrate community of small ditches was sampled at 40 sites of the orchard region Altes Land near Hamburg, Germany. To differentiate between pesticide impact and other variables, the ditches selected for sampling were located at different distances along grassland, unused apple orchards, and orchards managed with integrated and/or organic crop protection methods. Samples of macroinvertebrates were taken on five dates over two years. In addition to biological data, water chemistry and structural parameters were measured. For each sampling site, a potential for exposure was calculated on the basis of the distance of the ditch to the nearest row of trees and the depth and width of the ditch. The neighborhood to either grassland or orchards turned out to have a larger impact on the macroinvertebrate community than the potential for exposure. Therefore, grassland sites were omitted from further evaluation. Remaining sites were grouped into low exposure (sites at unused orchards), medium exposure (distance of 3,5 m [track] between trees and ditch), and high exposure (trees close to the ditch, mean distance , 1.5 m). Principal response curves showed differences in community structure between the three exposure groups over time. Whereas for sites from the high exposure group significant differences from low exposure was observed in all seasons, significant differences between low and medium were observed only occasionally. Effects were less pronounced in samples taken at springtime before the starting pesticide applications, suggesting some community recovery. Species richness was negatively correlated to exposure potential. Isopoda, Eulamellibranchiata, and insects, especially Ephemeroptera, showed a high negative correlation with the potential for pesticide exposure, suggesting that these taxa are sensitive to the pesticide use in the orchards. [source] Synchrony of spontaneous calcium activity in mouse neocortex before synaptogenesisEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2007Jean-Claude Platel Abstract Spontaneous calcium activity can be detected in embryonic mouse cortical slices as fluorescence intensity variations, in the presence of a fluorescent calcium indicator. Current methods to detect and quantify these variations depend heavily on experimenters whose judgement may interfere with measurement. In the present work, we developed new software called CalSignal for automatic detection and tracking of cellular bodies and quantification of spontaneous calcium activity on time-series of confocal fluorescence images. Analysis of 28 neocortical slices revealed that 21.0% of detected cells displayed peaks of fluorescence corresponding to spontaneous activity, with a mean frequency of one peak per 4 min. This activity was blocked in the absence of extracellular calcium but was not modified after depletion of calcium stores with thapsigargin or blockade of voltage-gated calcium channels with Ni2+. Further, statistical analysis of calcium activity revealed concomitant activation of distant cells in 24 slices, and the existence of a significant network of synchrony based on such coactivations in 17 slices out of 28. These networks enclosed 84.3% of active cells, scattered throughout the neocortical wall (mean distance between cellular bodies, 111.7 µm). Finally, it was possible to identify specific cells which were synchronously active with more neighbouring cells than others. The identity of these nodal cells remains to be investigated to fully comprehend the role of spontaneous calcium activity, before synaptogenesis, in shaping cortical neurogenesis. [source] Post-fledging behaviour in Golden Eagles Aquila chrysaetos: onset of juvenile dispersal and progressive distancing from the nestIBIS, Issue 2 2006ALVARO SOUTULLO Thirteen juvenile Golden Eagles Aquila chrysaetos were tracked during their first year of life using satellite telemetry. Distances to the nest attained during that period and the age at the onset of juvenile dispersal were explored. The performance of nine different criteria to determine that age was analysed. In general, after a brief period of restricted movements around the nest, the average distance to the nest increased with time. Maximum distances to the nest ranged between 57.7 and 184.3 km, and were considerably greater in females (mean ± sd, 138.5 ± 44.5 km) than in males (70.5 ± 14.0 km). No sex difference was observed in the age at which that distance was attained (males: 329 ± 32 days, females: 312 ± 20 days). The onset of juvenile dispersal took place around the fifth month of life (September in Spain). Eight of the nine criteria provided similar results, suggesting that in Spain dispersal starts when birds are between 140 and 180 days old, and that the post-nestling period lasts between 60 and 120 days. For future studies, to determine the age at which the onset of juvenile dispersal occurs, we recommend the use of either the first day on which individuals were located beyond the mean distance between nests of different pairs (10 km in our study area), or the date of the record midway between the first and the last location recorded during the month in which the maximum variability in the distance to the nest was observed. [source] Nest predators affect spatial dynamics of breeding red-backed shrikes (Lanius collurio)JOURNAL OF ANIMAL ECOLOGY, Issue 1 2004Staffan Roos Summary 1Predation may be a strong selective factor affecting individual behaviour and life histories. However, few studies have investigated whether predators affect breeding habitat selection of prey species. 2We tested whether breeding habitat selection and reproduction of a tropical migrant, the red-backed shrike (Lanius collurio L.), was related to the presence of breeding pairs of its potential nest predators, magpie (Pica pica L.), hooded crow (Corvus corone cornix L.) and jackdaw (C. monedula L.). 3Only magpie and hooded crow territories were associated with an elevated risk of predation based on an artificial nest experiment with nests mimicking red-backed shrike nests. Predation risk on real red-backed shrike nests was also higher close to nests of hooded crow and magpie than elsewhere in the landscape. 4Occupation frequency of known red-backed shrike territory sites during 3 years of study increased with increasing mean distance to the nearest magpie nest. 5Changes in spatial distribution of corvids affected the spatial distribution of red-backed shrikes. Vacant red-backed shrike territory sites were more likely to become occupied in the next year when magpie and hooded crows had moved away from the site, while occupied sites were more likely to be abandoned in the next year when at least hooded crows had moved closer. 6Our results suggest that breeding territories of nest predators may affect breeding habitat selection of prey species. Thus, a large part of an observed spatial dynamics of prey species may be caused by a corresponding spatial dynamics of predators. Because sink territories are occupied more irregularly than source territories, we suggest that the dynamics in predator sinks may be the driving force of the spatial dynamics of prey species. [source] Characterization of a New Pulmonary Vein Variant Using Magnetic Resonance Angiography:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2004Imaging, Incidence, Interventional Implications of the "Right Top Pulmonary Vein" Introduction: Catheter ablation of the pulmonary veins (PVs) for prevention of recurrent atrial fibrillation requires precise anatomic information. We describe the characteristics of a new anatomic variant of PV anatomy using magnetic resonance angiography. Methods and Results: A 1.5-T magnetic resonance imaging system with a body coil or a torso phased-array coil was used before and after gadolinium injection. Magnetic resonance angiograms were acquired with a breath-hold three-dimensional fast spoiled gradient-echo imaging sequence in the coronal plane. Three-dimensional reconstruction with maximum intensity projections and multiplanar reformations was performed. A newly described variant PV ascending from the roof of the left atrium was found in 3 of 91 subjects. The mean ostial diameter of the roof PV was 7 ± 2 mm, the mean distance from the ostium to the first branching point was 22 ± 8.5 mm, and the mean distance to the right superior PV was 3.3 ± 0.6 mm. Conclusion: We refer to the newly described variant of PV anatomy as the "right top pulmonary vein." It is important to be aware of this anatomic pattern to avoid inadvertent catheter intubation, which can result in misleading mapping results and PV stenosis. (J Cardiovasc Electrophysiol, Vol. 15, pp. 538-543, May 2004) [source] Topographic Anatomy of the Inferior Pyramidal Space: Relevance to Radiofrequency Catheter AblationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2001DAMIÁN SÁNCHEZ-QUINTANA M.D. Inferior Pyramidal Space and Ablation.Introduction: Radiofrequency catheter ablation carried out in the vicinity of the triangle of Koch risks damaging not only the AV conduction tissues but also their arterial supply. The aim of this study was to examine the relationship of the AV nodal artery to the inferior pyramidal space, the triangle of Koch, and the right atrial endocardial surface. Methods and Results: We studied 41 heart specimens, 24 by gross dissections and 17 by histologic sections. The proximity of the AV nodal artery to the surface landmarks of the triangle of Koch was variable, but it was notable that in 75% of specimens the artery passed close to the endocardial surface of the right atrium and within 0.5 to 5 mm of the mouth of the coronary sinus. In all specimens, the mean distance of the artery to the endocardial surface was 3.5 ± 1.5 mm at the base of Koch's triangle. The location of the compact AV node and its inferior extensions varied within the landmarks of the triangle. At the mid-level of Koch's triangle, the compact node was medially situated in 82% of specimens, but it was closer to the hinge of the tricuspid valve in the remaining 18% of specimens. In 12% of specimens, the inferior parts of the node extended to the level of the mouth of the coronary sinus. Conclusion: The nodal artery runs close to the orifice of the coronary sinus, the endocardial surface of the right atrium, the middle cardiac vein, and the specialized conduction tissues in most hearts. The nodal artery and/or the AV conduction tissues can be at risk of damage when ablative procedures are carried out at the base of the triangle of Koch. [source] The effect of drought stress and temperature on spread of barley yellow dwarf virus (BYDV)AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2000I. N. Smyrnioudis Summary 1 The effect of drought stress and temperature on the dispersal of wingless aphids Rhopalosiphum padi (L.) and the pattern of spread of BYDV (barley yellow dwarf virus) within wheat plants in controlled environment chambers was quantified. Combinations of three different drought stress levels, unstressed, moderate and high stress level, and three different temperatures, 5 ± 1 °C, 10 ± 1 °C, and 15 ± 1 °C, were investigated. 2 With increased temperature there was an increase in the mean distance of visited plants from the point of release and in the number of plants visited and infected with BYDV. Drought stress had no effect on mean distance moved by aphids at any temperature or on plants infected with virus at 10 °C and 5 °C. When plants were drought stressed, the numbers of plants visited and infected were greater at 15 °C than at 10 °C and 5 °C. 3 A greater proportion of plants visited by aphids was infected with BYDV when plants were stressed than when not stressed. At 15 °C a greater proportion of these plants was infected than at lower temperatures. There was no difference between treatments in the numbers of aphids present at the end of the experiment. 4 It is concluded that drought stress and temperature are of considerable importance in virus spread. [source] Regional patch dynamics of Cirsium arvense and possible implications for plant-animal interactionsJOURNAL OF VEGETATION SCIENCE, Issue 2 2003S. Eber Abstract. Plant population biology considers the dynamics of plant modules within stands. However, stands themselves may have considerable regional turnover in space and time. These changes in the number, distribution and size of plant stands generate a dynamic spatial pattern with important implications for the spatial and temporal dynamics of phytophagous insects using these plants as a host. During five successive years we studied the regional distribution and patch dynamics of the creeping thistle Cirsium arvense and the distribution of associated populations of the herbivore Urophora cardui (Diptera: Tephritidae), a specialist stem gall former. The study conducted was in a 15 km2 heterogeneous, agricultural area in northeastern Bavaria. The distribution of the number of plants per patch was skewed with many more small C. arvense patches than large ones. During the five years of study, there was a 50% increase in the number of C. arvense patches, and a decrease in the mean number of plants per patch (= patch size) to less than half the patch size of the first year. Whilst patch size was randomly distributed in space, patch density showed a consistent, non-random spatial pattern. Patch density was spatially auto-correlated, with areas of high or low patch density having a characteristic dimension of ca. 1 km. Patch size was predictable in time and appeared to be regulated by size dependent processes, with the extinction probability of a patch being negatively correlated with its size. Correlated with the decline of C. arvense patch size during the study, the occupancy and total numbers of the herbivore U. cardui had a marked decrease, suggesting that the regional distribution of the stem gall former is not only influenced by patch number but more importantly by the mean patch size. With decreasing patch sizes, U. cardui was faced with an increasingly dynamic landscape due to higher extinction rates of small patches, although the mean distance between host plant patches decreased. [source] Realized gene flow within mixed stands of Quercus robur L. and Q. petraea (Matt.) L. revealed at the stage of naturally established seedlingMOLECULAR ECOLOGY, Issue 10 2010I. J. CHYBICKI Abstract The estimates of contemporary gene flow assessed based on naturally established seedlings provide information much needed for understanding the abilities of forest tree populations to persist under global changes through migration and/or adaptation facilitated by gene exchange among populations. Here, we investigated pollen- and seed-mediated gene flow in two mixed-oak forest stands (consisting of Quercus robur L. and Q. petraea [Matt.] Liebl.). The gene flow parameters were estimated based on microsatellite multilocus genotypes of seedlings and adults and their spatial locations within the sample plots using models that attempt to reconstruct the genealogy of the seedling cohorts. Pollen and seed dispersal were modelled using the standard seedling neighbourhood model and a modification,the 2-component seedling neighbourhood model, with the later allowing separation of the dispersal process into local and long-distance components. The 2-component model fitted the data substantially better than the standard model and provided estimates of mean seed and pollen dispersal distances accounting for long-distance propagule dispersal. The mean distance of effective pollen dispersal was found to be 298 and 463 m, depending on the stand, while the mean distance of effective seed dispersal was only 8.8 and 15.6 m, which is consistent with wind pollination and primarily seed dispersal by gravity in Quercus. Some differences observed between the two stands could be attributed to the differences in the stand structure of the adult populations and the existing understory vegetation. Such a mixture of relatively limited seed dispersal with occasional long distance gene flow seems to be an efficient strategy for colonizing new habitats with subsequent local adaptation, while maintaining genetic diversity within populations. [source] Host density predicts presence of cuckoo parasitism in reed warblersOIKOS, Issue 6 2007Bĺrd G. Stokke In some hosts of avian brood parasites, several populations apparently escape parasitism, while others are parasitized. Many migratory specialist brood parasites like common cuckoos, Cuculus canorus, experience a short breeding season, and in order to maintain local parasite populations host densities should be sufficiently high to allow efficient nest search. However, no studies have investigated the possible effect of host density on presence of cuckoo parasitism among populations of a single host species. Here, we investigated possible predictors of common cuckoo parasitism in 16 populations of reed warblers, Acrocephalus scirpaceus, across Europe. In more detail, we quantified the effect of host density, number of host breeding pairs, habitat type, mean distance to nearest cuckoo vantage point, predation rate and latitude on the presence of cuckoo parasitism while controlling for geographical distance among study populations. Host density was a powerful predictor of parasitism. We also found a less pronounced effect of habitat type on occurrence of parasitism, while the other variables did not explain why cuckoos utilize some reed warbler populations and not others. This is the first study focusing on patterns of common cuckoo-host interactions within a specific host species on a large geographic scale. The results indicate that if host density is below a specific threshold, cuckoo parasitism is absent regardless of the state of other potentially confounding variables. [source] Roost preferences and foraging ranges of the eastern forest bat Vespadelus pumilus under two disturbance histories in northern New South Wales., AustraliaAUSTRAL ECOLOGY, Issue 4 2000BRADLEY S. LAW Abstract Little is known about the habitat requirements of Australian bats; however, this information is needed to make better-informed decisions when systems are disturbed. This study contrasts the roosting and foraging ecology of the eastern forest bat Vespadelus pumilus (Vespertilionidae), one of Australia's smallest bats, between two sites of differing disturbance history on the mid-north coast of New South Wales. Lome Flora Reserve (182 ha) is primarily old-growth forest surrounded by regrowth forest and eucalypt plantations, while Swans Crossing is dominated by regrowth and eucalypt plantations established on part of an old dairy farm. A total of 38 bats were tracked during the maternity and mating seasons at the two sites. Roost preferences were determined by comparing trees used as roosts with those randomly available, while foraging bats were triangulated from fixed stations at night. Bats tracked at Lome Flora Reserve typically roosted in hollows within large, mature trees and showed a strong preference for roosting and foraging (females only) within the Reserve. Lactating females at Swans Crossing roosted in hollows of remnant rainforest trees within a gully and dead eucalypts, while males often roosted in understorey trees (such as Acacia). Dead trees were frequently used as roosts at both sites. Under both disturbance histories, the mean distance of female maternity roosts from creeks was 20m, indicating that riparian zones provide important roosting habitat for V. pumilus. However, roosts shifted to the mid-slope prior to winter when bats mate. Retention of mature trees in a variety of topographic locations may allow behavioural adjustments with the seasons. Bats caught in the regrowth forest also foraged there, with foraging ranges averaging just 5.3 ha (n = 10), indicating that regrowth is used by this bat for both foraging and roosting. [source] Microsatellite distribution and indication for locoregional therapy in small hepatocellular carcinomaCANCER, Issue 2 2005Atsushi Sasaki M.D., Ph.D. Abstract BACKGROUND Intrahepatic disease recurrence is observed frequently after locoregional therapies for patients with hepatocellular carcinoma (HCC). However, the indication for locoregional therapy is still unclear. To clarify the indication for locoregional therapy for small HCC tumors, the authors measured the distance of microsatellites from the main tumor and analyzed the relation between this distance and clinicopathologic factors. METHODS The authors retrospectively analyzed 100 patients with small HCC tumors (, 5 cm in dimension) treated by curative hepatectomy. A microsatellite was defined as invasion into the portal vein or intrahepatic metastasis, and the distance from the main tumor to the most distant microsatellite was determined under light microscopy. The current study investigated the relation between microsatellite distance (0 mm if none present, , 5 mm, and > 5 mm) and clinicopathologic factors, as well as overall and disease-free survival rates after hepatectomy. RESULTS Of the 100 patients, 46 had microsatellites with a mean distance of 9.9 mm (median, 5.0 mm). Of the clinicopathologic factors investigated, tumor grade and preoperative ,-fetoprotein level significantly correlated with the presence of a microsatellite. Tumor size and distance to the microsatellite were significantly correlated. All but 1 tumor associated with a microsatellite distance > 5 mm was a high-grade tumor > 25 mm in greatest dimension. The overall survival rate of patients with a microsatellite distance of > 5 mm was lower than that of patients with a microsatellite distance < 5 mm. CONCLUSIONS Locoregional therapy, including limited resection and ablation therapies, was appropriate for patients with low-grade HCC tumors or with tumors < 25 mm in diameter. Cancer 2005. © 2004 American Cancer Society. [source] The gracilis muscle and its use in clinical reconstruction: An anatomical, embryological, and radiological studyCLINICAL ANATOMY, Issue 7 2008V. Macchi Abstract The gracilis muscle is used widely in reconstructive surgery, as a pedicled or as a free microsurgical flap, for soft tissue coverage or as a functioning muscle transfer. Many studies, based on cadaver dissections, have focused on the vascular anatomy of the gracilis muscle and provided different data about the number, origin, and caliber of its vascular pedicles. Computed tomographic (CT) angiography of both thighs of 40 patients (35 males and 5 females, mean age: 63 years) have been analyzed to provide a detailed anatomical description of the arterial supply of the gracilis muscle. The gracilis muscle had a mean length of 41 ± 2.1 cm. The principal pedicle enters the gracilis muscle at a mean distance (±SD) of 10 ± 1 cm from the ischiopubic attachment of the muscle. Its caliber shows a mean value of 2.5 ± 0.5 mm, and it is statistically larger when originating directly from the deep femoral artery (45%) than from its muscular branch supplying the adductors, i.e., the "artery to the adductors" (46%) (P < 0.01). A significant correlation between the caliber of the artery of the main pedicle and the volume of the gracilis muscle was found (P < 0.01). The mean number of distal accessory pedicles is 1.8 (range, 1,4,) and the artery of the first of these pedicles shows a mean caliber of 2.0 mm. There is no correlation between either the number or the caliber of the artery of the accessory pedicles and the volume of the gracilis muscle. CT angiography, providing detailed images of the muscular and vascular structures of the thigh of each patient, could be a useful preoperative study for the reconstructive surgeon. It would allow a personalized planning of a gracilis flap, reducing the risk of iatrogenic damage. Clin. Anat. 21:696,704, 2008. © 2008 Wiley-Liss, Inc. [source] Anatomy and quantitation of the subscapular nervesCLINICAL ANATOMY, Issue 6 2007R. Shane Tubbs Abstract Information regarding branches of the brachial plexus can be of utility to the surgeon for neurotization procedures following injury. Sixty-two adult cadaveric upper extremities were dissected and the subscapular nerves identified and measured. The upper subscapular nerve originated from the posterior cord in 97% of the cases and in 3% of the cases directly from the axillary nerve. The upper subscapular nerve originated as a single nerve in 90.3% of the cases, as two independent nerve trunks in 8% of the cases and as three independent nerve trunks in 1.6% of the cases. The thoracodorsal nerve originated from the posterior cord in 98.5% of the cases and in 1.5% of the cases directly from the proximal segment of the radial nerve. The thoracodorsal nerve always originated as a single nerve from the brachial plexus. The lower subscapular nerve originated from the posterior cord in 79% of the cases and in 21% of the cases directly from the proximal segment of the axillary nerve. The lower subscapular nerve originated as a single nerve in 93.6% of the cases and as two independent nerve trunks in 6.4% of the cases. The mean length of the lower subscapular nerve from its origin until it provided its branch into the subscapularis muscle was 3.5 cm and the mean distance from this branch until its termination into the teres major muscle was 6 cm. The mean diameter of this nerve was 1.9 mm. The mean length of the upper subscapular nerve from its origin to its termination into the subscapularis muscle was 5cm and the mean diameter of the nerve was 2.3 mm. The mean length of the thoracodorsal nerve from its origin to its termination into the latissimus dorsi muscle was 13.7 cm. The mean diameter of this nerve was 2.6 mm. Our hopes are that these data will prove useful to the surgeon in surgical planning for potential neurotization procedures of the brachial plexus. Clin. Anat. 20:656,659, 2007. © 2007 Wiley-Liss, Inc. [source] Movement of two grassland butterflies in the same habitat network: the role of adult resources and size of the study areaECOLOGICAL ENTOMOLOGY, Issue 2 2003Christine Schneider Abstract. 1., Movement patterns of two butterfly species (meadow brown Maniola jurtina L. and scarce copper Lycaenae virgaureae L.) were studied in a 172 ha area within a landscape with a high percentage of suitable habitats for mark,release,recapture experiments. 2., Adult resource density, but not patch size or larval food plant abundance, influenced the numbers and the fractions of residents, emigrants, and immigrants. 3., Differences between species were observed in movement frequency and maximum distances moved but not in mean distances moved. 4., The scarce copper showed much greater movement ability than expected from the results of published studies. This is believed to be a result of the comparatively large size of the study area and the high cover of suitable habitat (>50%). 5., The mean and maximum distances travelled by butterflies reflected differences in the size of the study area. [source] Temperament assessments of lactating cows in three contexts and their applicability as management traitsANIMAL SCIENCE JOURNAL, Issue 6 2004Katsuji UETAKE ABSTRACT The applicability of three behavioral assessments of lactating cows as management traits was verified. Flight responses to an approaching human (flight starting and walking distances, and flight walking speed) at pasture, entrance order into the milking parlour and step-kick behavior to cup attachment were observed for 713 subject cows in six Australasian dairy farms. On all farms, cows were kept at pasture without any barn housing. Flight responses were measured once, and other assessments were recorded repeatedly for each subject cow. A principal component analysis was performed to verify whether these assessments appear to measure the same trait. A two-way anova and correlation analyses were then used to test whether obtained principal components were affected by farm, age and milking stage of cows. Australian and some Japanese herd management systems were compared for flight distance using a one-way anova and a multiple comparison test. Three behavioral assessments clustered in different principal components, indicating that these assessments did not appear to measure the same trait. Factor scores of four principal components were affected by farm (all, P < 0.01), and the scores of principal component 1, interpreted as fear of humans (r = ,0.16, P < 0.01), and component 2, interpreted as aversion to cup attachment (r = ,0.28, P < 0.01), were moderately correlated with age. These results emphasize the necessity of data standardization to reduce the non-genetic variation resulting from these two affectors. The flight distance at pasture of herds in Australia (6.06 ± 2.85 m) was significantly (P < 0.05) different from the flight distances measured in paddocks (1.50 ± 0.82 m) and free-stall barns (1.22 ± 1.09 m) in Japan. However, mean distances were not different between the Australian herds at pasture and the Japanese herds at pasture in tie-stall barns (3.96 ± 2.16 m) or in a free-stall barn (4.03 ± 1.79 m). This difference could be a result of the fact that only a single measurement was made, so that repeated measurement might improve the usefulness of flight distance as a management trait. In conclusion, it was verified that step-kick behavior to cup attachment and flight responses to human approach were, although they have some affectors, applicable as objective management traits in lactating cows. [source] Fluoroscopic localization of the femoral head as a landmark for common femoral artery cannulation,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2005Paul D. Garrett MD Abstract We sought to determine the reliability of frequently used landmarks for femoral arterial access in patients undergoing cardiac catheterization. The common femoral artery (CFA) is the most frequently used arterial access in cardiac catheterization. Arterial sheath placement into the CFA has been shown to decrease vascular complications. Some authors recommend locating the inferior border of the femoral head using fluoroscopy due to the relationship of the femoral head and the bifurcation of the CFA. We performed a descriptive study in a prospective design of 158 patients undergoing catheterization from the femoral approach. A femoral angiogram was performed, and the CFA bifurcation location was recorded in relation to the inguinal ligament, middle and inferior border of the femoral head, and the inguinal skin crease. The CFA bifurcation was distal to the inguinal ligament, middle femoral head, and inferior femoral head in most patients with mean distances (cm ± SD) of 7.5 ± 1.7, 2.9 ± 1.5, and 0.8 ± 1.2, respectively. The inguinal skin crease was below the bifurcation in 78% of patients (,1.8 ± 1.6 cm). The CFA overlies the femoral head in 92% of cases. The femoral head has a consistent relationship to the CFA, and localization using fluoroscopy is a useful landmark. © 2005 Wiley-Liss, Inc. [source] Anatomical considerations of the deep peroneal nerve for biopsy of the proximal fibula in ThaisCLINICAL ANATOMY, Issue 2 2009S. Chompoopong Abstract The present research aims to study the anatomical relationship between the deep peroneal nerve and the neighboring structures in the proximal fibula of Thais, with special regard to define the boundaries of a "safe" area when performing a biopsy of the proximal fibula. The proximal parts of 118 legs of 59 formalin-embalmed adult cadavers (31 males, 28 females) were investigated. The distance from the apex of the fibular head to the point of origin of the deep peroneal nerve, the distance from the most lateral prominence of the fibular head to the anterior intermuscular septum, and the angle between the deep peroneal nerve and the fibula axis were measured. The results showed that the mean distances from the apex of the fibular head to the point of origin of the deep peroneal nerve was 28.4 ± 4.8 mm and from the most lateral prominence of the fibular head to the anterior intermuscular septum was 14.9 ± 2.0 mm. The mean angle between the deep peroneal nerve and the fibular axis was 28.1° ± 7.2°. In conclusion, these findings suggest that a "safe" area for bone biopsy in the proximal fibula of Thais is palpable anterior to the fibular head and downward laterally, not lower than 28 mm or 8% of the fibular length and from the most lateral prominence transverse medially not further than 14 mm. The inferior boundary of this area is an oblique line of the deep peroneal nerve about 28° from the fibular axis. Clin. Anat. 22:256,260, 2009. © 2008 Wiley-Liss, Inc. [source] | ||||||||||||||||