156 research outputs found

    First record of Trichoncus auritus (L. Koch, 1869) (Araneae, Linyphiidae, Erigoninae) from Germany

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    Anhand ausgewählter Taxozönosen der Regulatorengilde (Araneae, Opiliones, Carabidae, Staphylinidae) werden seit April1998 die langfristigen Auswirkungen waldbaulicher Eingriffe in den Überschirmungsgrad auf das Ökosystem Bergmischwald untersucht (JUNKER & ROTH i. Dr.). Dazu wird die epigäische Pradatorenfauna eines ca. 100-jährigen Bestandes in den Chiemgauer Alpen mittels Bodenfallen (BF) erfasst (Volumen: 370 ml, Durchmesser: 7 cm, Fixierflüssigkeit: gesättigte Benzoesäurelosung mit Detergens, Regenschutz: 15x15cm Plexiglas, Leerung: monatlich). Zusätzlich sind an weiteren Stellen in direkter Nachbarschaft zu den Untersuchungsflächen, so z. B. einem Schotterhang, Bodenfallen installiert, um einen umfassenderen Eindruck von der Fauna des Untersuchungsgebietes zu erhalten (s. Artenliste in Tab. 1). Im Rahmen dieser Untersuchung konnte die Zwergspinnen-Art Trichoncus auritus (L. Koch, 1869) erstmals für das Gebiet der Bundesrepublik Deutschland nachgewiesen werden

    Handling software upgradeability problems with MILP solvers

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    Upgradeability problems are a critical issue in modern operating systems. The problem consists in finding the "best" solution according to some criteria, to install, remove or upgrade packages in a given installation. This is a difficult problem: the complexity of the upgradeability problem is NP complete and modern OS contain a huge number of packages (often more than 20 000 packages in a Linux distribution). Moreover, several optimisation criteria have to be considered, e.g., stability, memory efficiency, network efficiency. In this paper we investigate the capabilities of MILP solvers to handle this problem. We show that MILP solvers are very efficient when the resolution is based on a linear combination of the criteria. Experiments done on real benchmarks show that the best MILP solvers outperform CP solvers and that they are significantly better than Pseudo Boolean solvers.Comment: In Proceedings LoCoCo 2010, arXiv:1007.083

    Efficient processing of an antigenic sequence for presentation by MHC class I molecules depends on its neighboring residues in the protein

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    Processing of endogenously synthesized proteins generates short peptides that are presented by MHC class I molecules to CD8 T lymphocytes. Here it is documented that not only the sequence of the presented peptide but also the residues by which it is flanked in the protein determine the efficiency of processing and presentation. This became evident when a viral sequence of proven antigenicity was inserted at different positions into an unrelated carrier protein. Not different peptides, but different amounts of the antigenic insert itself were retrieved by isolation of naturally processed peptides from cells expressing the different chimeric proteins. Low yield of antigenic peptide from an unfavorable integration site could be overcome by flanking the insert with oligo-alanine to space it from disruptive neighboring sequences. Notably, the degree of protection against lethal virus disease related directly to the amount of naturally processed antigenic peptide

    Catchment-scale patterns of geomorphic activity and vegetation distribution in an alpine glacier foreland (Kaunertal Valley, Austria)

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    The interaction between geomorphological and ecological processes plays a significant role in determining landscape patterns in glacier forelands. However, the spatial organization of this biogeomorphic mosaic remains unclear due to limited catchment-scale data. To address this gap, we used a multi-proxy analysis to map potential geomorphic activity related to surface changes induced by sediment transport on drift-mantled slopes and a glaciofluvial plain. High-resolution vegetation data were used to generate a catchment-scale map delineating vegetation cover and stability thresholds. The two maps were integrated, and an exploratory regression analysis was conducted to investigate the influence of geomorphic activity on vegetation colonization. The multi-proxy analysis resulted in an accurate mapping of catchment-wide geomorphic activity, with a validation accuracy ranging from 75.3% through field mapping to 85.9% through plot sampling. Through vegetation cover mapping, we identified biogeomorphic stability thresholds, revealing a mosaic of vegetation distribution. Distinct colonization patterns emerged across different geomorphic process groups, influenced by process magnitude and the time since the last disturbance event. The exploratory regression analysis showed that vegetation distribution is significantly affected by geomorphic processes. Based on the overlay of results regarding geomorphic activity and vegetation distribution, we suggest an age-independent framework that indicates four potential situations of biogeomorphic succession

    Introducing LoCo, a Logic for Configuration Problems

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    In this paper we present the core of LoCo, a logic-based high-level representation language for expressing configuration problems. LoCo shall allow to model these problems in an intuitive and declarative way, the dynamic aspects of configuration notwithstanding. Our logic enforces that configurations contain only finitely many components and reasoning can be reduced to the task of model construction.Comment: In Proceedings LoCoCo 2011, arXiv:1108.609

    Logical Imputation to Optimize Prognostic Risk Classification in Metastatic Renal Cell Cancer

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    BACKGROUND: Application of the MSKCC and IMDC models is recommended for prognostication in metastatic renal cell cancer (mRCC). Patient classification in MSKCC and IMDC risk groups in real-world observational studies is often hampered by missing data on required pre-treatment characteristics. OBJECTIVES: To evaluate the effect of application of easy-to-use logical, or deductive, imputation on MSKCC and IMDC risk classification in an observational study setting. PATIENTS AND METHODS: We used data on 713 mRCC patients with first-line sunitinib treatment from our observational European multi-centre study EuroTARGET. Pre-treatment characteristics and follow-up were derived from medical files. Hospital-specific cut-off values for laboratory measurements were requested. The effect of logical imputation of missing data and consensus versus hospital-specific cut-off values on patient classification and the subsequent models' predictive performance for progression-free and overall survival (OS) was evaluated. RESULTS: 45% of the patients had missing data for >= 1 pre-treatment characteristic for either model. Still, 72% of all patients could be unambiguously classified using logical imputation. Use of consensus instead of hospital-specific cut-offs led to a shift in risk group for 12% and 7% of patients for the MSKCC and IMDC model, respectively. Using logical imputation or other cut-offs did not influence the models' predictive performance. These were in line with previous reports (c-statistic similar to 0.64 for OS). CONCLUSIONS: Logical imputation leads to a substantial increase in the proportion of patients that can be correctly classified into poor and intermediate MSKCC and IMDC risk groups in observational studies and its use in the field should be advocated
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