University of Konstanz

About: University of Konstanz is a education organization based out in Konstanz, Baden-Württemberg, Germany. It is known for research contribution in the topics: Population & Membrane. The organization has 12115 authors who have published 27401 publications receiving 951162 citations. The organization is also known as: University of Constance & Universität Konstanz.

Metabolic Differentiation of Distinct Muscle Types at the Level of Enzymatic Organization

Abstract: Metabolic differentiation of muscle tissue may be understood from the viewpoints of quantitative and qualitative adaptation. Quantitatively, it is the consequence of a balance of input of chemical energy and output of mechanical work in the myofibrillar apparatus. Qualitatively, it is the expression of an adjustment to the functional characteristics of the muscle, such as the quality and temporal pattern of energy expenditure (e.g. steady and continuous, steady and discontinuous or dicontinuous performance of work. The kinds of metabolic differentiation possible are based on the fact that muscle cells may draw energy from the oxidation of various fuels. The caloric values of the various fuels determine their different theoretical maximum energy-yields. The nature of the fuel also determines the type of its metabolism, especially with regard to an obligatory or nonobligatory aerobic catabolism. Energy-output in cell metabolism depends finally on the catabolic rate. Nature of the fuel, type of metabolism and catabolic rate thus represent fundamental elements in metabolic differentiation.

‚The Good, the Bad, and the Ugly‘

Abstract: Folgt man dem einflussreichsten Beitrag zur vergleichenden Wohlfahrtsstaatsforschung der letzten Zeit, Esping-Andersens „Three Worlds of Welfare Capitalism“, so tritt der entwickelte westliche Sozialstaat in drei Varianten auf: entweder als sozialdemokratisches, als konservatives oder als liberales Wohlfahrtsstaatsregime. Ein genauerer Blick zeigt, dass Esping-Andersens Typenbildung und Landerzuordnungen insbesondere im Fall des konservativen Regimes sehr problematisch sind. Der Beitrag argumentiert, dass diese gravierenden Probleme daher ruhren, dass seine Theorie vornehmlich den Klassenkonflikt, nur selektiv aber den Einfluss konfessioneller Faktoren in den Blick nimmt. Wesentliche theoretische Widerspruche und empirische Unstimmigkeiten seines Ansatzes lassen sich losen, wenn man neben der Bedeutung der katholischen Soziallehre fur den institutionellen Entwicklungspfad des Sozialstaats auch den Einfluss des Protestantismus, und hier insbesondere den Einfluss der freikirchlichen Stromungen des Protestantismus und des Calvinismus beachtet. Der Beitrag zeigt dies mit vergleichenden Daten sowohl fur die Fruhphase (1890 bis 1920), als auch fur die Hochzeit des entwickelten Wohlfahrtsstaats (von 1960 bis 1990).

Research-paper recommender systems: a literature survey

Abstract: In the last 16 years, more than 200 research articles were published about research-paper recommender systems. We reviewed these articles and present some descriptive statistics in this paper, as well as a discussion about the major advancements and shortcomings and an overview of the most common recommendation concepts and approaches. We found that more than half of the recommendation approaches applied content-based filtering (55 %). Collaborative filtering was applied by only 18 % of the reviewed approaches, and graph-based recommendations by 16 %. Other recommendation concepts included stereotyping, item-centric recommendations, and hybrid recommendations. The content-based filtering approaches mainly utilized papers that the users had authored, tagged, browsed, or downloaded. TF-IDF was the most frequently applied weighting scheme. In addition to simple terms, n-grams, topics, and citations were utilized to model users' information needs. Our review revealed some shortcomings of the current research. First, it remains unclear which recommendation concepts and approaches are the most promising. For instance, researchers reported different results on the performance of content-based and collaborative filtering. Sometimes content-based filtering performed better than collaborative filtering and sometimes it performed worse. We identified three potential reasons for the ambiguity of the results. (A) Several evaluations had limitations. They were based on strongly pruned datasets, few participants in user studies, or did not use appropriate baselines. (B) Some authors provided little information about their algorithms, which makes it difficult to re-implement the approaches. Consequently, researchers use different implementations of the same recommendations approaches, which might lead to variations in the results. (C) We speculated that minor variations in datasets, algorithms, or user populations inevitably lead to strong variations in the performance of the approaches. Hence, finding the most promising approaches is a challenge. As a second limitation, we noted that many authors neglected to take into account factors other than accuracy, for example overall user satisfaction. In addition, most approaches (81 %) neglected the user-modeling process and did not infer information automatically but let users provide keywords, text snippets, or a single paper as input. Information on runtime was provided for 10 % of the approaches. Finally, few research papers had an impact on research-paper recommender systems in practice. We also identified a lack of authority and long-term research interest in the field: 73 % of the authors published no more than one paper on research-paper recommender systems, and there was little cooperation among different co-author groups. We concluded that several actions could improve the research landscape: developing a common evaluation framework, agreement on the information to include in research papers, a stronger focus on non-accuracy aspects and user modeling, a platform for researchers to exchange information, and an open-source framework that bundles the available recommendation approaches.

Towards complete and error-free genome assemblies of all vertebrate species

Abstract: High-quality and complete reference genome assemblies are fundamental for the application of genomics to biology, disease, and biodiversity conservation. However, such assemblies are available for only a few non-microbial species1-4. To address this issue, the international Genome 10K (G10K) consortium5,6 has worked over a five-year period to evaluate and develop cost-effective methods for assembling highly accurate and nearly complete reference genomes. Here we present lessons learned from generating assemblies for 16 species that represent six major vertebrate lineages. We confirm that long-read sequencing technologies are essential for maximizing genome quality, and that unresolved complex repeats and haplotype heterozygosity are major sources of assembly error when not handled correctly. Our assemblies correct substantial errors, add missing sequence in some of the best historical reference genomes, and reveal biological discoveries. These include the identification of many false gene duplications, increases in gene sizes, chromosome rearrangements that are specific to lineages, a repeated independent chromosome breakpoint in bat genomes, and a canonical GC-rich pattern in protein-coding genes and their regulatory regions. Adopting these lessons, we have embarked on the Vertebrate Genomes Project (VGP), an international effort to generate high-quality, complete reference genomes for all of the roughly 70,000 extant vertebrate species and to help to enable a new era of discovery across the life sciences.

Panel Data Analysis in Comparative Politics: Linking Method to Theory

Abstract: Re-analyzing a study of Garrett and Mitchell ('Globalization, government spend- ing and taxation in the OECD', European Journal of Political Research 39(2) (2001): 145-177), this article addresses four potential sources of problems in panel data analyses with a lagged dependent variable and period and unit dummies (the de facto Beck-Katz standard). These are: absorption of cross-sectional variance by unit dummies, absorption of time-series variance by the lagged dependent variable and period dummies, mis-specifica- tion of the lag structure, and neglect of parameter slope heterogeneity. Based on this dis- cussion, we suggest substantial changes of the estimation approach and the estimated model. Employing our preferred methodological stance, we demonstrate that Garrett and Mitchell's findings are not robust. Instead, we show that partisan politics and socioeconomic factors such as aging and unemployment as expected by theorists have a strong impact on the time- series and cross-sectional variance in government spending.