35 research outputs found

    First estimation of Eurasian lynx (Lynx lynx) abundance and density using digital cameras and capture–recapture techniques in a German national park

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    Primera estima de la abundancia y de la densidad del lince euroasiático (Lynx lynx) utilizando cámaras digitales y técnicas de captura–recaptura en un parque nacional alemán Al lince euroasiático se le puede identificar individualmente mediante las marcas de su pelaje, que son únicas, lo que le convierte en un candidato ideal para los estudios de captura–recaptura (CMR). Hemos evaluado el uso de la fotografía digital para estimar la abundancia y la densidad de la población del lince euroasiático en el Parque Nacional Forestal Bávaro. Desde noviembre del 2008 a enero del 2009 establecimos 24 lugares de trampeo, cada uno de ellos provisto de dos cámaras encaradas entre sí, en lugares de paso frecuentados. Colocamos las unidades basándonos en una cuadrícula sistemática de 2,7 km. Capturamos cinco linces independientes y tres jóvenes, y calculamos las estimas de abundancia utilizando el programa Mark. También comparamos las estimas de densidad mediante el método MMDM (distancia media máxima recorrida) de datos telemétricos (½MMDMGPS) y de datos de las cámaras trampa (½MMDMCAM). Hallamos que en un área muestreada eficazmente de 664 km2 la densidad del lince euroasiático era de 0,9 individuos/100 km2 mediante ½MMDMCAM. La densidad del lince euroasiático calculada mediante el método ½MMDMGPS fue de 0,4 individuos/100 km2 en una zona muestreada eficazmente de 1.381 km2. Nuestros resultados sugieren que un muestreo fotográfico CMR a largo plazo y a gran escala puede ser una herramienta muy útil para monitorizar las tendencias poblacionales del lince euroasiático, según la Directiva de Hábitat, Flora y Fauna de la Unión Europea.Primera estima de la abundancia y de la densidad del lince euroasiático (Lynx lynx) utilizando cámaras digitales y técnicas de captura–recaptura en un parque nacional alemán Al lince euroasiático se le puede identificar individualmente mediante las marcas de su pelaje, que son únicas, lo que le convierte en un candidato ideal para los estudios de captura–recaptura (CMR). Hemos evaluado el uso de la fotografía digital para estimar la abundancia y la densidad de la población del lince euroasiático en el Parque Nacional Forestal Bávaro. Desde noviembre del 2008 a enero del 2009 establecimos 24 lugares de trampeo, cada uno de ellos provisto de dos cámaras encaradas entre sí, en lugares de paso frecuentados. Colocamos las unidades basándonos en una cuadrícula sistemática de 2,7 km. Capturamos cinco linces independientes y tres jóvenes, y calculamos las estimas de abundancia utilizando el programa Mark. También comparamos las estimas de densidad mediante el método MMDM (distancia media máxima recorrida) de datos telemétricos (½MMDMGPS) y de datos de las cámaras trampa (½MMDMCAM). Hallamos que en un área muestreada eficazmente de 664 km2 la densidad del lince euroasiático era de 0,9 individuos/100 km2 mediante ½MMDMCAM. La densidad del lince euroasiático calculada mediante el método ½MMDMGPS fue de 0,4 individuos/100 km2 en una zona muestreada eficazmente de 1.381 km2. Nuestros resultados sugieren que un muestreo fotográfico CMR a largo plazo y a gran escala puede ser una herramienta muy útil para monitorizar las tendencias poblacionales del lince euroasiático, según la Directiva de Hábitat, Flora y Fauna de la Unión Europea.ABC_35-2_2012 First estimation of Eurasian lynx (Lynx lynx) abundance and density using digital cameras and capture–recapture techniques in a German national park Weingarth, K., Heibl, C., Knauer, F., Zimmermann, F., Bufka, L., Heurich, M. Abstract Eurasian lynx are individually identifiable by their unique coat markings, making them ideal candidates for capture–recapture (CMR) surveys. We evaluated the use of digital photography to estimate Eurasian lynx population abundance and density within the Bavarian Forest National Park. From November 2008 to January 2009 we placed 24 camera trap sites, each with two cameras facing each other on well–used walking tracks). The units were placed based on a systematic grid of 2.7 km. We captured five independent and three juvenile lynx and calculated abundance estimates using Program Mark. We also compared density estimates based on the MMDM method (Mean Maximum Distance Moved) from telemetry data (½MMDMGPS) and from camera trapping data (½MMDMCAM). We estimated that in an effectively sampled area of 664 km2 the Eurasian lynx density was 0.9 individuals/100 km2 with ½MMDMCAM. The Eurasian lynx density calculated with ½MMDMGPS was 0.4 individuals/100 km2 in an effectively sampled area of 1,381 km2. Our results suggest that long–term photographic CMR sampling on a large scale may be a useful tool to monitor population trends of Eurasian lynx in accordance with the Fauna–Flora–Habitat Directive of the European Union

    Landscape of HER2-low metastatic breast cancer (MBC): results from the Austrian AGMT_MBC-Registry

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    BACKGROUND: About 50% of all primary breast cancers show a low-level expression of HER2 (HER2-low), defined as immunohistochemically 1+ or 2+ and lack of HER2 gene amplification measured by in situ hybridization. This low HER2 expression is a promising new target for antibody-drug conjugates (ADCs) currently under investigation. Until now, little is known about the frequency and the prognostic value of low HER2-expression in metastatic breast cancer (MBC). PATIENTS AND METHODS: The MBC-Registry of the Austrian Study Group of Medical Tumor Therapy (AGMT) is a multicenter nationwide ongoing registry for MBC patients in Austria. Unadjusted, univariate survival probabilities of progression-free survival (PFS) and overall survival (OS) were calculated by the Kaplan-Meier method and compared by the log-rank test. Multivariable adjusted hazard ratios were estimated by Cox regression models. In this analysis, only patients with known HER2 status and available survival data were included. RESULTS: As of 11/15/2020, 1,973 patients were included in the AGMT-MBC-Registry. Out of 1,729 evaluable patients, 351 (20.3%) were HER2-positive, 608 (35.2%) were HER2-low and 770 (44.5%) were completely HER2-negative (HER2-0). Low HER2-expression was markedly more frequent in the hormone-receptor(HR)+ subgroup compared to the triple-negative subgroup (40% vs. 23%). In multivariable analysis, low HER2 expression did not significantly influence OS neither in the HR+ (HR 0.89; 95% CI 0.74-1.05; P = 0.171) nor in the triple-negative subgroup (HR 0.92; 95% CI 0.68-1.25; P = 0.585), when compared to completely HER2-negative disease. Similar results were observed when HER2 IHC 2+ patients were compared to IHC 1+ or 0 patients. CONCLUSION: Low-HER2 expression did not have any impact on prognosis of metastatic breast cancer in this real-world population

    Radar vision in the mapping of forest biodiversity from space

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    Recent progress in remote sensing provides much-needed, large-scale spatio-temporal information on habitat structures important for biodiversity conservation. Here we examine the potential of a newly launched satellite-borne radar system (Sentinel-1) to map the biodiversity of twelve taxa across five temperate forest regions in central Europe. We show that the sensitivity of radar to habitat structure is similar to that of airborne laser scanning (ALS), the current gold standard in the measurement of forest structure. Our models of different facets of biodiversity reveal that radar performs as well as ALS; median R² over twelve taxa by ALS and radar are 0.51 and 0.57 respectively for the first non-metric multidimensional scaling axes representing assemblage composition. We further demonstrate the promising predictive ability of radar-derived data with external validation based on the species composition of birds and saproxylic beetles. Establishing new area-wide biodiversity monitoring by remote sensing will require the coupling of radar data to stratified and standardized collected local species data

    European mushroom assemblages are darker in cold climates

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    Abstract: Thermal melanism theory states that dark-colored ectotherm organisms are at an advantage at low temperature due to increased warming. This theory is generally supported for ectotherm animals, however, the function of colors in the fungal kingdom is largely unknown. Here, we test whether the color lightness of mushroom assemblages is related to climate using a dataset of 3.2 million observations of 3,054 species across Europe. Consistent with the thermal melanism theory, mushroom assemblages are significantly darker in areas with cold climates. We further show differences in color phenotype between fungal lifestyles and a lifestyle differentiated response to seasonality. These results indicate a more complex ecological role of mushroom colors and suggest functions beyond thermal adaption. Because fungi play a crucial role in terrestrial carbon and nutrient cycles, understanding the links between the thermal environment, functional coloration and species’ geographical distributions will be critical in predicting ecosystem responses to global warming

    The contribution of insects to global forest deadwood decomposition

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    The amount of carbon stored in deadwood is equivalent to about 8 per cent of the global forest carbon stocks. The decomposition of deadwood is largely governed by climate with decomposer groups—such as microorganisms and insects—contributing to variations in the decomposition rates. At the global scale, the contribution of insects to the decomposition of deadwood and carbon release remains poorly understood. Here we present a field experiment of wood decomposition across 55 forest sites and 6 continents. We find that the deadwood decomposition rates increase with temperature, and the strongest temperature effect is found at high precipitation levels. Precipitation affects the decomposition rates negatively at low temperatures and positively at high temperatures. As a net effect—including the direct consumption by insects and indirect effects through interactions with microorganisms—insects accelerate the decomposition in tropical forests (3.9% median mass loss per year). In temperate and boreal forests, we find weak positive and negative effects with a median mass loss of 0.9 per cent and −0.1 per cent per year, respectively. Furthermore, we apply the experimentally derived decomposition function to a global map of deadwood carbon synthesized from empirical and remote-sensing data, obtaining an estimate of 10.9 ± 3.2 petagram of carbon per year released from deadwood globally, with 93 per cent originating from tropical forests. Globally, the net effect of insects may account for 29 per cent of the carbon flux from deadwood, which suggests a functional importance of insects in the decomposition of deadwood and the carbon cycle

    Reptilia, Serpentes, Colubridae, <i>Tachymenis Wiegmann</i>,1836: Latitudinal and altitudinal distribution extension in Chile

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    Observations and pictures of two snakes, Tachymenis peruviana Wiegmann, 1836, and Tachymenis chilensis(Schlegel, 1837), were taken in the Atacama coastal desert, province of Antofagasta, Chile. Furthermore, in the collection of the Museo Nacional de Historia Natural de Santiago, we found two individuals of T. c. chilensis from Cachapoal and Talcaprovinces. These records represent a northward extension of the known range of T. c. chilensis along the Andean foothillsof more than 180 km

    First estimation of Eurasian lynx (Lynx lynx) abundance and density using digital cameras and capture–recapture techniques in a German national park

    No full text
    Eurasian lynx are individually identifiable by their unique coat markings, making them ideal candidates for capture–recapture (CMR) surveys. We evaluated the use of digital photography to estimate Eurasian lynx population abundance and density within the Bavarian Forest National Park. From November 2008 to January 2009 we placed 24 camera trap sites, each with two cameras facing each other on well–used walking tracks). The units were placed based on a systematic grid of 2.7 km. We captured five independent and three juvenile lynx and calculated abundance estimates using Program Mark. We also compared density estimates based on the MMDM method (Mean Maximum Distance Moved) from telemetry data (½MMDMGPS) and from camera trapping data (½MMDMCAM). We estimated that in an effectively sampled area of 664 km2 the Eurasian lynx density was 0.9 individuals/100 km2 with ½MMDMCAM. The Eurasian lynx density calculated with ½MMDMGPS was 0.4 individuals/100 km2 in an effectively sampled area of 1,381 km2. Our results suggest that long–term photographic CMR sampling on a large scale may be a useful tool to monitor population trends of Eurasian lynx in accordance with the Fauna–Flora–Habitat Directive of the European Union
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