828 research outputs found

    Tracking movements of Athene owls: the application of North American experiences to Europe

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    Seguimiento de los desplazamiento de los mochuelos del género Athene: aplicación de las experiencias norteamericanas a Europa Migración y dispersión son procesos importantes desde el punto de vista de la ecología y la evolución, y entenderlos es un requisito importante para los programas de conservación de las especies. El mochuelo de madriguera, Athene cunicularia, el equivalente norteamericano del mochuelo europeo, A. noctua, es migratorio en las zonas septentrionales de su área de acción. En Canadá sus poblaciones han disminuido de forma notoria, y se han clasificado como amenazadas. Se han estudiado los desplazamientos del mochuelo de madriguera utilizando el anillado, la telemetría VHF, los isótopos estables, la genética (ADN), los geolocalizadores y los transmisores por satélite. Los geolocalizadores y los transmisores por satélite proporcionan la información más fiable sobre las migraciones, pero para su buen funcionamiento dependen de la exposición a la luz solar, que es limitada en el caso de las rapaces nocturnas. Los hallazgos de animales anillados, y los flujos migratorios invernales del mochuelo común hacia España, incluyendo las Islas Baleares, indican que pueden estarse dando desplazamientos migratorios. Un estudio mediante isótopos estables podría determinar si entre los mochuelos que invernan en el sur de Europa, se incluyen mochuelos del norte de Europa. Palabras clave: Athene, Desplazamientos, Migración, Dispersión, Técnicas.Migration and dispersal are important ecological and evolutionary processes and understanding them is a requirement for species conservation efforts. Burrowing owl, Athene cunicularia, the North American equivalent of little owl, A. noctua, is migratory in the northern parts of its range. In Canada their populations have declined dramatically and are classified as endangered. Movements of burrowing owls have been studied using banding (ringing), VHF telemetry, stable isotopes, genetics (DNA), geolocators and satellite transmitters. Geolocators and satellite transmitters provide the most reliable information about migrations but to operate successfully they are both dependent upon exposure to sunlight, which can be limited for nocturnal owls. Ringing encounters and winter influxes of little owls into Spain, including the Balearic Islands, indicate that some migration movement may be occurring. A stable isotope study could determine if wintering owls in southern Europe includes owls originating in northern Europe. Key words: Athene, Movements, Migration, Dispersal, Techniques.Seguimiento de los desplazamiento de los mochuelos del género Athene: aplicación de las experiencias norteamericanas a Europa Migración y dispersión son procesos importantes desde el punto de vista de la ecología y la evolución, y entenderlos es un requisito importante para los programas de conservación de las especies. El mochuelo de madriguera, Athene cunicularia, el equivalente norteamericano del mochuelo europeo, A. noctua, es migratorio en las zonas septentrionales de su área de acción. En Canadá sus poblaciones han disminuido de forma notoria, y se han clasificado como amenazadas. Se han estudiado los desplazamientos del mochuelo de madriguera utilizando el anillado, la telemetría VHF, los isótopos estables, la genética (ADN), los geolocalizadores y los transmisores por satélite. Los geolocalizadores y los transmisores por satélite proporcionan la información más fiable sobre las migraciones, pero para su buen funcionamiento dependen de la exposición a la luz solar, que es limitada en el caso de las rapaces nocturnas. Los hallazgos de animales anillados, y los flujos migratorios invernales del mochuelo común hacia España, incluyendo las Islas Baleares, indican que pueden estarse dando desplazamientos migratorios. Un estudio mediante isótopos estables podría determinar si entre los mochuelos que invernan en el sur de Europa, se incluyen mochuelos del norte de Europa. Palabras clave: Athene, Desplazamientos, Migración, Dispersión, Técnicas

    Home range and habitat use of little owl (athene noctua) in an agricultural landscape in coastal catalonia, Spain

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    In recent decades agricultural landscapes in Catalonia have undergone a profound transformation as in most of Europe. Reforestation and urban development have reduced farmland and therefore the availability of suitable habitat for some bird species such as the little owl (Athene noctua). The outskirts of the city of Mataró by the Mediterranean Sea exemplify this landscape change, but still support a population of little owl where agriculture is carried out. Three resident little owls were monitored with telemetry weekly from November 2007 until the beginning of August 2008 in this suburban agricultural landscape. Mean home range ± SD was 10.9 ± 5.5 ha for minimum convex polygon (MCP100) and 7.4 ± 3.8 ha for Kernel 95% probability function (K95). Home ranges of contiguous neighboring pairs overlapped 18.4% (MCP100) or 6% (K95). Home range varied among seasons reaching a maximum between March and early August but always included the nesting site. Small forested patches were associated with roosting and nesting areas where cavities in carob trees (Ceratonia siliqua) were important. When foraging in crop fields, the owls typically fed where crops had recently been harvested and replanted. All three owls bred successfully

    Home range and habitat use of little owl (Athene noctua) in an agricultural landscape in coastal Catalonia, Spain

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    Área de campeo y uso del hábitat del mochuelo europeo (Athene noctua) en un paisaje agrícola de la costa de Cataluña, España El paisaje agrícola en Cataluña ha sufrido una profunda transformación en las últimas décadas, tal y como ha ocurrido en gran parte de Europa. La reforestación y especialmente el desarrollo urbanístico han reducido las tierras agrícolas y con ello se ha perdido hábitat adecuado para especies como el mochuelo europeo (Athene noctua). Los alrededores de la ciudad de Mataró, a orillas del Mar Mediterráneo, son un buen ejemplo de este cambio, pero todavía acogen una población de mochuelos allí donde se da actividad agrícola. Entre noviembre de 2007 y principios de agosto de 2008 se siguieron semanalmente con telemetría tres mochuelos residentes en este entorno agrícola periurbano. La media del área de campeo ± DE estimada con el polígono convexo mínimo (MCP100) fue de 10,9 ± 5,5 ha, y de 7,4 ± 3,8 ha, con el estimador de Kernel 95% (K95). Las áreas de campeo de las parejas vecinas se solapaban un 18,4% (MCP100) o un 6% (K95). Las áreas de campeo entre temporadas variaron a lo largo del seguimiento y llegaron a un máximo entre marzo y principios de agosto, aunque éstas siempre albergaron la zona del nido. Las pequeñas manchas arboladas se asociaron a áreas de reposo y nidificación, donde las cavidades naturales de los algarrobos (Ceratonia siliqua) eran importantes. Cuando los mochuelos se detectaron en los campos, fue en cultivos recién cosechados o replantados. Los tres mochuelos criaron con éxito. Palabras clave: Mochuelo europeo, Athene noctua, Telemetría, Conservación, Área vital, Área de campeo, Uso del hábitat, Paisaje agrícola.In recent decades agricultural landscapes in Catalonia have undergone a profound transformation as in most of Europe. Reforestation and urban development have reduced farmland and therefore the availability of suitable habitat for some bird species such as the little owl (Athene noctua). The outskirts of the city of Mataró by the Mediterranean Sea exemplify this landscape change, but still support a population of little owl where agriculture is carried out. Three resident little owls were monitored with telemetry weekly from November 2007 until the beginning of August 2008 in this suburban agricultural landscape. Mean home range ± SD was 10.9 ± 5.5 ha for minimum convex polygon (MCP100) and 7.4 ± 3.8 ha for Kernel 95% probability function (K95). Home ranges of contiguous neighboring pairs overlapped 18.4% (MCP100) or 6% (K95). Home range varied among seasons reaching a maximum between March and early August but always included the nesting site. Small forested patches were associated with roosting and nesting areas where cavities in carob trees (Ceratonia siliqua) were important. When foraging in crop fields, the owls typically fed where crops had recently been harvested and replanted. All three owls bred successfully. Key words: Little owl, Athene noctua, Telemetry, Conservation, Home range, Habitat use, Agricultural landscapeÁrea de campeo y uso del hábitat del mochuelo europeo (Athene noctua) en un paisaje agrícola de la costa de Cataluña, España El paisaje agrícola en Cataluña ha sufrido una profunda transformación en las últimas décadas, tal y como ha ocurrido en gran parte de Europa. La reforestación y especialmente el desarrollo urbanístico han reducido las tierras agrícolas y con ello se ha perdido hábitat adecuado para especies como el mochuelo europeo (Athene noctua). Los alrededores de la ciudad de Mataró, a orillas del Mar Mediterráneo, son un buen ejemplo de este cambio, pero todavía acogen una población de mochuelos allí donde se da actividad agrícola. Entre noviembre de 2007 y principios de agosto de 2008 se siguieron semanalmente con telemetría tres mochuelos residentes en este entorno agrícola periurbano. La media del área de campeo ± DE estimada con el polígono convexo mínimo (MCP100) fue de 10,9 ± 5,5 ha, y de 7,4 ± 3,8 ha, con el estimador de Kernel 95% (K95). Las áreas de campeo de las parejas vecinas se solapaban un 18,4% (MCP100) o un 6% (K95). Las áreas de campeo entre temporadas variaron a lo largo del seguimiento y llegaron a un máximo entre marzo y principios de agosto, aunque éstas siempre albergaron la zona del nido. Las pequeñas manchas arboladas se asociaron a áreas de reposo y nidificación, donde las cavidades naturales de los algarrobos (Ceratonia siliqua) eran importantes. Cuando los mochuelos se detectaron en los campos, fue en cultivos recién cosechados o replantados. Los tres mochuelos criaron con éxito. Palabras clave: Mochuelo europeo, Athene noctua, Telemetría, Conservación, Área vital, Área de campeo, Uso del hábitat, Paisaje agrícola

    Guidelines for measuring and reporting environmental parameters for experiments in greenhouses

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    Background: The importance of appropriate, accurate measurement and reporting of environmental parameters in plant sciences is a significant aspect of quality assurance for all researchers and their research. There is a clear need for ensuring research across the world can be compared, understood and where necessary replicated by fellow researchers. A common set of guidelines to educate, assist and encourage comparativeness is of great importance. On the other hand, the level of effort and attention to detail by an individual researcher should be commensurate with the particular research being conducted. For example, a researcher focusing on interactions of light and temperature should measure all relevant parameters and report a measurement summary that includes sufficient detail allowing for replication. Such detail may be less relevant when the impact of environmental parameters on plant growth and development is not the main research focus. However, it should be noted that the environmental experience of a plant during production can have significant impact when subsequent experiments investigate plants at a molecular, biochemical or genetic level or where species interactions are considered. Thus, researchers are encouraged to make a critical assessment of what parameters are of primary importance in their research and these parameters should be measured and reported. Content: This paper brings together a collection of parameters that the authors, as members of International Committee on Controlled Environment Guidelines (ICCEG) in consultation with members of our three parent organizations, believe constitute those which should be recorded and reported when publishing scientific data from experiments in greenhouses. It provides recommendations to end users on when, how and where these parameters should be measured along with the appropriate internationally standardized units that should be used

    A drug repurposing screen for whipworms informed by comparative genomics.

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    Hundreds of millions of people worldwide are infected with the whipworm Trichuris trichiura. Novel treatments are urgently needed as current drugs, such as albendazole, have relatively low efficacy. We have investigated whether drugs approved for other human diseases could be repurposed as novel anti-whipworm drugs. In a previous comparative genomics analysis, we identified 409 drugs approved for human use that we predicted to target parasitic worm proteins. Here we tested these ex vivo by assessing motility of adult worms of Trichuris muris, the murine whipworm, an established model for human whipworm research. We identified 14 compounds with EC50 values of ≤50 μM against T. muris ex vivo, and selected nine for testing in vivo. However, the best worm burden reduction seen in mice was just 19%. The high number of ex vivo hits against T. muris shows that we were successful at predicting parasite proteins that could be targeted by approved drugs. In contrast, the low efficacy of these compounds in mice suggest challenges due to their chemical properties (e.g. lipophilicity, polarity, molecular weight) and pharmacokinetics (e.g. absorption, distribution, metabolism, and excretion) that may (i) promote absorption by the host gastrointestinal tract, thereby reducing availability to the worms embedded in the large intestine, and/or (ii) restrict drug uptake by the worms. This indicates that identifying structural analogues that have reduced absorption by the host, and increased uptake by worms, may be necessary for successful drug development against whipworms

    Stress corrosion cracking in Al-Zn-Mg-Cu aluminum alloys in saline environments

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    Copyright 2013 ASM International. This paper was published in Metallurgical and Materials Transactions A, 44A(3), 1230 - 1253, and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.Stress corrosion cracking of Al-Zn-Mg-Cu (AA7xxx) aluminum alloys exposed to saline environments at temperatures ranging from 293 K to 353 K (20 °C to 80 °C) has been reviewed with particular attention to the influences of alloy composition and temper, and bulk and local environmental conditions. Stress corrosion crack (SCC) growth rates at room temperature for peak- and over-aged tempers in saline environments are minimized for Al-Zn-Mg-Cu alloys containing less than ~8 wt pct Zn when Zn/Mg ratios are ranging from 2 to 3, excess magnesium levels are less than 1 wt pct, and copper content is either less than ~0.2 wt pct or ranging from 1.3 to 2 wt pct. A minimum chloride ion concentration of ~0.01 M is required for crack growth rates to exceed those in distilled water, which insures that the local solution pH in crack-tip regions can be maintained at less than 4. Crack growth rates in saline solution without other additions gradually increase with bulk chloride ion concentrations up to around 0.6 M NaCl, whereas in solutions with sufficiently low dichromate (or chromate), inhibitor additions are insensitive to the bulk chloride concentration and are typically at least double those observed without the additions. DCB specimens, fatigue pre-cracked in air before immersion in a saline environment, show an initial period with no detectible crack growth, followed by crack growth at the distilled water rate, and then transition to a higher crack growth rate typical of region 2 crack growth in the saline environment. Time spent in each stage depends on the type of pre-crack (“pop-in” vs fatigue), applied stress intensity factor, alloy chemistry, bulk environment, and, if applied, the external polarization. Apparent activation energies (E a) for SCC growth in Al-Zn-Mg-Cu alloys exposed to 0.6 M NaCl over the temperatures ranging from 293 K to 353 K (20 °C to 80 °C) for under-, peak-, and over-aged low-copper-containing alloys (~0.8 wt pct), they are typically ranging from 20 to 40 kJ/mol for under- and peak-aged alloys, and based on limited data, around 85 kJ/mol for over-aged tempers. This means that crack propagation in saline environments is most likely to occur by a hydrogen-related process for low-copper-containing Al-Zn-Mg-Cu alloys in under-, peak- and over-aged tempers, and for high-copper alloys in under- and peak-aged tempers. For over-aged high-copper-containing alloys, cracking is most probably under anodic dissolution control. Future stress corrosion studies should focus on understanding the factors that control crack initiation, and insuring that the next generation of higher performance Al-Zn-Mg-Cu alloys has similar longer crack initiation times and crack propagation rates to those of the incumbent alloys in an over-aged condition where crack rates are less than 1 mm/month at a high stress intensity factor

    Extracellular non-coding RNA signatures of the metacestode stage of Echinococcus multilocularis

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    Extracellular RNAs (ex-RNAs) are secreted by cells through different means that may involve association with proteins, lipoproteins or extracellular vesicles (EV). In the context of parasitism, ex-RNAs represent new and exciting communication intermediaries with promising potential as novel biomarkers. In the last years, it was shown that helminth parasites secrete ex-RNAs, however, most work mainly focused on RNA secretion mediated by EV. Ex-RNA study is of special interest in those helminth infections that still lack biomarkers for early and/or follow-up diagnosis, such as echinococcosis, a neglected zoonotic disease caused by cestodes of the genus Echinococcus. In this work, we have characterised the ex-RNA profile secreted by in vitro grown metacestodes of Echinococcus multilocularis, the casuative agent of alveolar echinococcosis. We have used high throughput RNA-sequencing together with RT-qPCR to characterise the ex-RNA profile secreted towards the extra- and intra-parasite milieus in EV-enriched and EV-depleted fractions. We show that a polarized secretion of small RNAs takes place, with microRNAs mainly secreted to the extra-parasite milieu and rRNA- and tRNA-derived sequences mostly secreted to the intra-parasite milieu. In addition, we show by nanoparticle tracking analyses that viable metacestodes secrete EV mainly into the metacestode inner vesicular fluid (MVF); however, the number of nanoparticles in culture medium and MVF increases > 10-fold when metacestodes show signs of tegument impairment. Interestingly, we confirm the presence of host miRNAs in the intra-parasite milieu, implying their internalization and transport through the tegument towards the MVF. Finally, our assessment of the detection of Echinococcus miRNAs in patient samples by RT-qPCR yielded negative results suggesting the tested miRNAs may not be good biomarkers for this disease. A comprehensive study of the secretion mechanisms throughout the life cycle of these parasites will help to understand parasite interaction with the host and also, improve current diagnostic tools

    Cooperative Behavior of Kinetically Constrained Lattice Gas Models of Glassy Dynamics

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    Kinetically constrained lattice models of glasses introduced by Kob and Andersen (KA) are analyzed. It is proved that only two behaviors are possible on hypercubic lattices: either ergodicity at all densities or trivial non-ergodicity, depending on the constraint parameter and the dimensionality. But in the ergodic cases, the dynamics is shown to be intrinsically cooperative at high densities giving rise to glassy dynamics as observed in simulations. The cooperativity is characterized by two length scales whose behavior controls finite-size effects: these are essential for interpreting simulations. In contrast to hypercubic lattices, on Bethe lattices KA models undergo a dynamical (jamming) phase transition at a critical density: this is characterized by diverging time and length scales and a discontinuous jump in the long-time limit of the density autocorrelation function. By analyzing generalized Bethe lattices (with loops) that interpolate between hypercubic lattices and standard Bethe lattices, the crossover between the dynamical transition that exists on these lattices and its absence in the hypercubic lattice limit is explored. Contact with earlier results are made via analysis of the related Fredrickson-Andersen models, followed by brief discussions of universality, of other approaches to glass transitions, and of some issues relevant for experiments.Comment: 59 page

    A study of general practitioners' perspectives on electronic medical records systems in NHS Scotland

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    <b>Background</b> Primary care doctors in NHSScotland have been using electronic medical records within their practices routinely for many years. The Scottish Health Executive eHealth strategy (2008-2011) has recently brought radical changes to the primary care computing landscape in Scotland: an information system (GPASS) which was provided free-of-charge by NHSScotland to a majority of GP practices has now been replaced by systems provided by two approved commercial providers. The transition to new electronic medical records had to be completed nationally across all health-boards by March 2012. <p></p><b> Methods</b> We carried out 25 in-depth semi-structured interviews with primary care doctors to elucidate GPs' perspectives on their practice information systems and collect more general information on management processes in the patient surgical pathway in NHSScotland. We undertook a thematic analysis of interviewees' responses, using Normalisation Process Theory as the underpinning conceptual framework. <p></p> <b>Results</b> The majority of GPs' interviewed considered that electronic medical records are an integral and essential element of their work during the consultation, playing a key role in facilitating integrated and continuity of care for patients and making clinical information more accessible. However, GPs expressed a number of reservations about various system functionalities - for example: in relation to usability, system navigation and information visualisation. <b>Conclusion </b>Our study highlights that while electronic information systems are perceived as having important benefits, there remains substantial scope to improve GPs' interaction and overall satisfaction with these systems. Iterative user-centred improvements combined with additional training in the use of technology would promote an increased understanding, familiarity and command of the range of functionalities of electronic medical records among primary care doctors
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