bluuebunny/crossref_metadata_2025_split huggingface dataset:
Matrix Trees
Authors: Andrysco Nathan , Tricoche Xavier 
Published: August 2010

AbstractWe propose a new data representation for octrees and kd‐trees that improves upon memory size and algorithm speed of existing techniques. While pointerless approaches exploit the regular structure of the tree to facilitate efficient data access, their memory footprint becomes prohibitively large as the height of the tree increases. Pointerbased trees require memory consumption proportional to the number of tree nodes, thus exploiting the typical sparsity of large trees. Yet, their traversal is slowed by the need to follow explicit pointers across the different levels. Our solution is a pointerless approach that represents each tree level with its own matrix, as opposed to traditional pointerless trees that use only a single vector. This novel data organization allows us to fully exploit the tree's regular structure and improve the performance of tree operations. By using a sparse matrix data structure we obtain a representation that is suited for sparse and dense trees alike. In particular, it uses less total memory than pointer‐based trees even when the data set is extremely sparse. We show how our approach is easily implemented on the GPU and illustrate its performance in typical visualization scenarios.
Infliximab efficacy in nail psoriasis. A retrospective study in 48 patients
Authors: Fabroni C , Gori A , Troiano M , Prignano F , Lotti T 
Published: August 2010

AbstractBackground  Nail psoriasis occurs in up to half of psoriatic patients and can lead to significant physical impairment and pain. To date, patients and clinicians are actually dissatisfied by current therapeutic approaches.Objective  Our main aim is to evaluate Infliximab efficacy in nail psoriasis.Methods  We performed an open‐label and uncontrolled retrospective study considering all psoriatic patients presenting recalcitrant nail involvement and receiving Infliximab in our Department during the period between January 2008 and March 2009. We calculated nail psoriasis severity index (NAPSI) score at 0, 14, 22 and 38 weeks and percentage of patients achieving NAPSI‐50,‐75,‐90 at 14, 22 and 38 weeks.Results  We observed a rapid nail improvement in most cases after 22 weeks of Infliximab therapy, but a complete nail clearing was reached in only five (10.4%) patients. We don’t have a follow‐up longer than 38 weeks to assess long‐term efficacy of this treatment in nail psoriasis.Conclusions  Infliximab, in our experience, has proved to be effective in reducing nail lesions and, in some cases, even clearing them. Our data demonstrate long‐term efficacy of this biological agent in nail psoriasis.
Agreeing in Principle: Utilitarianism and Economic Values as Support for the European Union in Central and Eastern Europe
Authors: LOVELESS MATTHEW 
Published: August 2010

AbstractUsing new mass surveys in central and eastern Europe, this article tests utilitarianism and economic values as the bases of support for the European Union. Advancing our understanding, the empirical findings point to increasingly nuanced economic criteria as the perception of social inequality strongly and independently influences EU support.
The photophore morphology of Selenoteuthis scintillans Voss and other lycoteuthids (Cephalopoda: Lycoteuthidae)
Authors: Herring P. J. , Dilly P. N. , Cope Celia 
Published: August 2010

Females and juveniles of Selenoteuthis scintillans have photophores of several structural types, distributed on the tentacles and eyeballs, and within the mantle cavity and tail. Three distinct photophore types can be recognized on the basis of their accessory structures, though their photocytes are identical. The tail and some tentacular photophores (Type 1) lack any accessory optical structures; other tentacular and abdominal photophores (Type 2) have collagenous diffusing fibres; the anal and ocular photophores (Type 3) have a variety of iridosomes but no collagen. The distal tentacular organ is a double structure composed of a unit each of Type 1 and Type 2. Ocular photophores 1 and 5 are also double structures, composed of two Type 3 units. The photophores closely resemble in structure those of Lycoteuthis diadema. The photocytes have a marked fluorescence and luminesce on treatment with dilute hydrogen peroxide. The bio‐luminescence intensity of the tail organ may be modified by chromatophore movements and has a blue‐green spectral emission.The photophores of juvenile Lampadioteuthis megaleia are similar in structure to those of Selenoteuthis but somewhat less complex. A comparison between the morphology of the photophores of lycoteuthid and enoploteuthid squids emphasizes the close similarity between the two families. At the ultrastructural level, certain photophores of both families have very characteristic microvillous blood vessels associated with the photocytes.
Surface‐mound formation by the Tuco‐tuco, Ctenomys fulvus (Rodentia: Ctenomyidae), with comments on earth‐pushing in other fossorial mammals
Authors: Hickman Graham C. 
Published: August 2010

Surface‐mound formation by Ctenomys fulvus (and evidently most Ctenomyidae, an autochthonous South American family) differs from most other fossorial mammals in that soil is transported to the surface by kicking with the hind feet (a habit shared with most Bathyergidae. the African mole‐rats). The greatly enlarged hind feet of Ctenomys are the largest for any terrestrial fossorial group. The eyes of Ctenomys, also different from many mole types, are large and appear better protected by hind foot soil‐pushing. The manner in which the stocky tail of Ctenomys supports the body above the substratum while kicking synchronously with the hind feet is unusual for any mammal.The body facing forward while pushing soil, the position favoured by most mole‐types, allows for the scanning of the surface for predators and defence through the use of teeth, claws and direct vocalizing, while hind foot soil‐pushing conserves energy by negating the need to turn around in the tunnel after digging, and again after depositing soil on the surface. Studies are required to determine the efficiency of various predators on the capture of mole‐types as soil is being pushed on to the surface, perhaps the most significant selective pressure on the manner of pushing soil.
Energetics of age‐specific reproductive effort in female Harp seals, Phoca groenlandica
Authors: Atewart Robert E. A. 
Published: August 2010

The theory of reproductive effort is commonly viewed in the perspective of the cost of offspring to the parent. This interpretation predicts that older females make a greater reproductive effort than younger females, for whom the cost of lost future offspring is less. The benefit early‐born offspring represent in future generations is greater than that of late‐born offspring in most natural populations, so, alternatively, young females should make a greater reproductive effort. These hypotheses were investigated in nursing Harp seals by examining age‐specific reproductive effort in terms of energetic maternal investment.Younger Harp seal females lost weight at the same rate as did older females. Moreover. since younger, growing females tended to start lactation with less blubber than older females. weight loss during 10 days (d) of lactation represented a greater proportion of stored energy for young females. A successfully weaned pup, therefore, constituted a greater reproductive effort for them than for older females, consistent with benefit–oriented predictions from theory.A model is presented to outline the components of an annual energy budget for female Harp seals in the context of reproductive effort. This model indicates that young females may devote a greater proportion of their annual net energy to reproduction and take a greater risk of lost future reproduction. It also identifies areas of inadequacy of existing data on pinniped energy budgets.
Peripheral innervation pattern in myotomal muscle of two teleosts as revealed by intracellular marking
Authors: Egginton S. , Johnston I. A. 
Published: August 2010

Spinal nerves of abdominal and trunk segments from cod (Gadus morhua L.) and freshwater eel (Anguilla anguilla L.) were examined by light and electron microscopy and major differences in peripheral innervation patterns investigated.Histochemically stained frozen sections clearly resolve the focal (terminal) innervation of eel fast fibres (one endplate/fibre) and the multiple innervation pattern of cod trunk muscle (around 20 endplates/fibre). Sub junctional folds are absent from eel and poorly developed in cod neuro‐muscular junctions (NMJs). A single population of synaptic vesicles with mean diameter of22–25 nm is found in the NMJs of both species.Cobalt chloride was used as an intracellular marker to map the branching between spinal roots and fast muscle endplates. Evidence was obtained for substantial inter‐segmental branching of the ventral rami in cod but not in eel. Previous classification schemes, dividing fishes according to the presence of separate or mixed motor and sensory axon populations within the ventral rami, are shown to be dependent upon sample location. In this study, the ventral rami of both species contain mixed populations, having modal diameters around 2 μm and8–12 μm, with the proportion of small diameter (sensory) axons much higher in cod than eel. The results suggest a more coarse control of body curvature in cod but an increased importance of pro‐prioreceptors in generating the locomotory wave.
Broadening the Extinction Debate: Population Deletions and Additions in California and Western Australia
Authors: Hobbs Richard J. , Mooney Harold A. 
Published: August 2010

Current discussions of biodiversity frequently center on the question of species extinction, and much of conservation biology focuses on this topic. We argue that species extinction often represents the endpoint of a process of population extinctions, and that the deletion of populations over much of a species’ range is likely to be of as much or more concern than the final extinction of that species. Population extinctions often result from habitat destruction and modification, which can be widespread. The result is that species can be deleted from most of their former range but continue to persist in small refuge areas. Moreover, species additions in the form of invasive species are frequently more numerous than extinctions in any given area. Such invasions often result in dramatic changes in ecosystem structure or function and can be instrumental in hastening the extinction of native populations. We examine these premises using two examples from California and Western Australia. These two contrasting areas show broadly similar trends in species extinctions, range contractions, and invasions, and they illustrate the fact that, by concentrating on species extinctions, many of the important human effects on biodiversity can be overlooked.Ampliando el Debate sobre Extinción: Eliminación y Adición de Poblaciones en California y Australia del OesteDiscusiones recientes sobre biodiversidad frecuentemente se centran en la extinción de las especies y una buena parte de la biología de la conservación se enfoca en este tema. Nosotros argumentamos que la extinción de especies representa frecuentemente el punto final de un proceso de extinciones de poblaciones y que la desaparición de poblaciones en la mayoría del rango de una especie es probablemente tanto o mas preocupante como la extinción final de las especies. Extinciones de poblaciones constantemente resultan de la destrucción y modificación del hábitat; lo cual puedo ocurrir con una extensión amplia. El resultado es que las especies pueden ser eliminadas de la mayoría de su rango original, pero continúan persistiendo en pequeñas áreas de refugio. Mas aún, la adición de especies en forma de especies invasivas son con frecuencia mas numerosas que las extinciones en un área determinada. Estas invasiones resultan frecuentemente en cambios dramáticos en la estructura of función del ecosistema y pueden ser el instrumento acelerador de la extinción de especies nativas. Examinamos estas premisas usando los ejemplos de California y Australia del Oeste. Estas dos contrastantes áreas muestran amplias tendencias similares en la extinción de especies, contracciones en rangos de distribución e invasiones. Además ilustran el hecho de que al enfocarnos en la extinción de especies muchos de los impactos humanos importantes en la biodiversiadad pueden ser desestimados.
Present and Future Taxonomic Selectivity in Bird and Mammal Extinctions
Authors: Russell Gareth J. , Brooks Thomas M. , McKinney Michael M. , Anderson C. Gregory 
Published: August 2010

We compared the distribution of historical bird and mammal species extinctions across genera and families with the distribution we would expect if these extinctions had occurred at random with respect to taxonomy. We then repeated the comparison for species listed in various categories of threat according to the 1996 Red List of the World Conservation Union. We found the distributions of extinctions and threat classifications to be almost always nonrandom—“selective”—with clustering in certain genera and families. Furthermore, extinctions tended to be clustered in taxa that contain few species; species in smaller genera tended to have higher probabilities of extinction. This tendency was strong for historical extinctions but was reduced or absent for some categories of threat. We attribute this to a change in the causes of extinction whereby predation and introduced species have been joined or superseded by widespread habitat loss. We then assessed the implications of this variable selectivity for the past and likely future losses of genera and families. In most cases, the number of lost taxa rises. Finally, we made predictions about minimum losses of taxa at specific dates in the future and showed that, despite the reduction in some forms of selectivity, we will still lose more taxa than if species extinctions were random.Selectividad Taxonómica Presente y Futura Extinciones de Aves y MamíferosSe comparó la distribución de las extinciones históricas de especies de aves y mamíferos con la distribución que se esperaría si las extinciones hubieran ocurrido al azar con respecto a la taxonomía. La comparación fue repetida para las especies incluidas en distintas categorías de riesgo en la Lista Roja de la UICN. En casi todos los casos se encontró que las distribuciones de las extinciones y de las categorías de riesgo no estaban distribuidas al azar, sin que fueron ‘selectivas,’ con distribución agrupada en ciertos géneros y familias. Se observó, además, que las extinciones tendieron a estar agrupadas en taxones que contienen pocas especies; las especies en géneros más pequeños tienden a tener mayores probabilidades de extinción. Esta tendencia fue fuerte para las extinciones históricas, pero reducida o ausente para algunas categorías de riesgo. Esto se atribuyó a un cambio en las causas de extinción, donde la predación y las especies introducidas se han sumado o han sido reemplazadas por la gran destrucción de hábitat. Se evaluaron luego las consecuencias de esta selectividad variable para las extinciones de géneros y familias en el pasado y en un futuro probable. En la mayoría de los casos el número de taxones extinguidos aumenta. Finalmente, se hicieron predicciones acerca de las extinciones mínimas de taxones en el futuro, demostrándose que, a pesar de la reducción en algunas formas de selectividad, se extinguirán más taxones que si las extinciones fueran al azar.
New Insights on Cheetah Conservation through Demographic Modeling
Authors: Crooks Kevin R. , Sanjayan M. A. , Doak Daniel F. 
Published: August 2010

Researchers have recently argued that ecological factors, especially high levels of cub predation, are more important than genetic impoverishment in limiting wild populations of the endangered cheetah (Acinonyx jubatus). Despite considerable controversy, however, the forces actually driving cheetah population dynamics remain unclear. We used a combination of demographic techniques to investigate how variation in survival and reproduction might influence the population persistence of wild cheetahs. We parameterized our models using detailed demographic data from recently published, long‐term ecological projects on cheetahs of the Serengeti. Results suggest that the influence of juvenile survivorship on population growth rate is relatively small compared to the large effects of adult survivorship. This result is consistent across a range of vital rates and is robust to deviations due to sampling error and environmental variability. These conclusions cast a new light on the current cheetah controversy and, more generally, counsel caution in the interpretation of ecological data for conservation and management. Nuevas Ideas para la Conservación del Leopardo Mediante Modelado Demográfico Recientemente los investigadores han argumentado que los factores ecológicos, especialmente altos niveles de depredación de cachorros, son mas importantes que el empobrecimiento genético en poblaciones silvestres limitadas del leopardo (Acinonyx jubatus), amenazado de extinción. Sin embargo, a pesar de considerables controversias, las fuerzas que actualmente conducen a las poblaciones del leopardo no son claras. Utilizamos una combinación de técnicas demográficas para investigar como la variación en la sobrevivencia y reproducción puede influir en la persistencia de poblaciones de leopardos. Nuestros modelos fueron parametrizados usando datos demográficos detallados de proyectos de largo plazo recientemente publicados de leopardos del Serengeti. Los resultados sugieren que la influencia de la supervivencia de juveniles en el crecimiento poblacional es relativamente pequeña en comparación con los grandes efectos de la sobrevivencia de los adultos. Estos resultados son consistentes a lo largo de un rango de tasas vitales y es robusto a desviaciones debidas a errores de muestreo y variabilidad ambiental. Estas conclusiones proyectan una nueva luz en la actual controversia sobre leopardos y en lo general aconsejan precaución en la interpretación de datos ecológicos para conservación y manejo.
A Reevaluation of the Role of Prairie Dogs in Great Plains Grasslands
Authors: Stapp Paul 
Published: August 2010

Recent articles in the scientific literature and popular press have argued for federal protection for prairie dogs (Cynomys ludovicianus) based on their role as a keystone species in North American grasslands. A critical evaluation of published studies, however, reveals that our knowledge of the effects of prairie dogs on other animals may be more limited and equivocal than these articles suggest. Moreover, differences in responses to grazing and disturbance of the types of grasslands inhabited by prairie dogs suggest that prairie dogs may affect the vegetation and fauna of these systems differently, yet we know little about their ecological role in many grasslands. Future research may provide convincing evidence that prairie dogs have disproportionately large, unique effects on prairie ecosystems, but it may be premature to characterize prairie dogs as keystone species in grasslands throughout the Great Plains. Despite decades of interest in and study of the effects of this conspicuous and influential species, large gaps in our knowledge of the ecology of prairie dogs persist and warrant additional research.Reevalución del Papel de Perros de Pradera en los Pastizales de la Gran PlanicieArtículos recientes en la literatura científica y la prensa han argumentado la protección federal de los perros de pradera (Cynomys ludovicianus) en base a su papel como especie clave en los pastizales de Norteamérica. Sin embargo, una evaluación crítica de los estudios publicados revela que nuestro conocimiento de los efectos de los perros de pradera en otros animales puede ser más limitado y equívoco de lo que estos artículos sugieren. Mas aún, diferencias en respuestas a pastoreo y otras perturbaciones etre los tipos de pastizales habitados por los perros de pradera sugieren que los perros pueden afectar la vegetación y la fauna de estos sistemas de forma diferente, sin embargo, conocemos muy poco sobre su papel ecológico en muchos pastizales. Información futura podría proveer evidencias convincentes de que los perros de pradera tienen efectos desproporcionadamente grandes y únicos en los ecosistemas de pradera, pero sería prematuro caracterizar a los perros como una especie clave en pastizales a lo largo de la Gran Planicie. A pesar de décadas de interés y estudio de los efectos de estas especies conspicuas e influyentes, aún permanecen grandes espacios vacíos en el conocimiento de la ecología de los perros de pradera, mismos que merecen investigación adicional.
Retrograde Occlusive Arteriography of Hemodialysis Access: Failure to Detect Inflow Lesions?
Authors: Chan Micah R. , Chhokar Vikramjit S. , Young Henry N. , Becker Bryan N. , Yevzlin Alexander S. 
Published: August 2010

AbstractOnce thought to be a minor player in hemodialysis (HD) access dysfunction relative to outflow stenosis, inflow stenosis has recently come to be viewed as a major cause of access failure. Indeed, recent literature has shown that up to 40% of all accesses referred for dysfunction have an inflow lesion. Imaging of the inflow segment has been traditionally performed by interventional nephrologists via retrograde occlusive arteriography (ROA). Recent advances in our understanding of ROA have cast the technique in a negative light, with the possibility of vascular complications and poor diagnostic yield coming to the fore. Using a prospectively collected, vascular access database, we identified 18 consecutive patients who received imaging of inflow lesions by ROA and direct arteriogram (DA). The mean percent luminal stenoses were found to be 59.89 ± 24 and 79.06 ± 17.8 (p = 0.009) for the ROA vs. DA groups, respectively. Using multiple regression analysis, DA was found to be associated with detecting higher degree of luminal stenosis (β = 19.17, 95% CI 6.28–32.05, p = 0.006). This small case series provides evidence on the theoretical concern that ROA does not adequately evaluate inflow lesions. We may conclude that by relying solely on ROA, interventional nephrologists may be failing to detect a subset of hemodynamically significant inflow lesions.