7,048 research outputs found

    Strangeness S=-2 baryon-baryon interaction at next-to-leading order in chiral effective field theory

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    The strangeness S=−2S=-2 baryon-baryon interaction is studied in chiral effective field theory up to next-to-leading order. The potential at this order consists of contributions from one- and two-pseudoscalar-meson exchange diagrams and from four-baryon contact terms without and with two derivatives. SU(3) flavor symmetry is imposed for constructing the interaction in the S=−2S=-2 sector. Specifically, the couplings of the pseudoscalar mesons to the baryons are fixed by SU(3) symmetry and, in general, also the contact terms are related via SU(3) symmetry to those determined in a previous study of the S=−1S=-1 hyperon-nucleon interaction. The explicit SU(3) symmetry breaking due to the physical masses of the pseudoscalar mesons (π\pi, KK, η\eta) is taken into account. It is argued that the ΞN\Xi N interaction has to be relatively weak to be in accordance with available experimental constraints. In particular, the published values and upper bounds for the Ξ−p\Xi^- p elastic and inelastic cross sections apparently rule out a somewhat stronger attractive ΞN\Xi N force and, specifically, disfavor any near-threshold deuteron-like bound states in that system.Comment: 17 pages, 7 figure

    Optimizing Electrode Placement for Hemodynamic Benefit in Cardiac Resynchronization Therapy

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    Background: Research is needed to explore the relative benefits of alternative electrode placements in biventricular and left ventricular pacing for heart failure with left bundle branch block (LBBB). Methods: A fast computational model of the left ventricle, running on an ordinary laptop computer, was created to simulate the spread of electrical activation over the myocardial surface, together with the resulting electrocardiogram, segmental wall motion, stroke volume, and ejection fraction in the presence of varying degrees of mitral regurgitation. Arbitrary zones of scar and blocked electrical conduction could be modeled. Results: Simulations showed there are both sweet spots and poor spots for left ventricular electrode placement, sometimes separated by only a few centimeters. In heart failure with LBBB pacing at poor spots can produce little benefit or even reduced pumping effectiveness. Pacing at sweet spots can produce up to 35% improvement in ejection fraction. Relatively larger benefit occurs in dilated hearts, in keeping with the greater disparity between early and late activated muscle. Sweet spots are typically located on the basal to mid-level, inferolateral wall. Poor spots are located on or near the interventricular septum. Anteroapical scar with conduction block causes little shift in locations for optimal pacing. Hearts with increased passive ventricular compliance and absence of pre-ejection mitral regurgitation exhibit greater therapeutic gain. The durations and wave shapes of QRS complexes in the electrocardiogram can help predict optimum electrode placement in real time. Conclusions: Differences between poor responders and hyper-responders to cardiac resynchronization therapy can be understood in terms of basic anatomy, physiology, and pathophysiology. Computational modeling suggests general strategies for optimal electrode placement. In a given patient heart size, regional pathology, and regional dynamics allow individual pre-treatment planning to target optimal electrode placement

    A Vector-Integration-to-Endpoint Model for Performance of Viapoint Movements

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    Viapoint (VP) movements are movements to a desired point that are constrained to pass through an intermediate point. Studies have shown that VP movements possess properties, such as smooth curvature around the VP, that are not explicable by treating VP movements as strict concatenations of simpler point-to-point (PTP) movements. Such properties have led some theorists to propose whole-trajectory optimization models, which imply that the entire trajectory is pre-computed before movement initiation. This paper reports new experiments conducted to systematically compare VP with PTP trajectories. Analyses revealed a statistically significant early directional deviation in VP movements but no associated curvature change. An explanation of this effect is offered by extending the Vector-Integration-To-Endpoint (VITE) model (Bullock and Grossberg, 1988), which postulates that voluntary movement trajectories emerge as internal gating signals control the integration of continuously computed vector commands based on the evolving, perceptible difference between desired and actual position variables. The model explains the observed trajectories of VP and PTP movements as emergent properties of a dynamical system that does not precompute entire trajectories before movement initiation. The new model includes a working memory and a stage sensitive to time-to-contact information. These cooperate to control serial performance. The structural and functional relationships proposed in the model are consistent with available data on forebrain physiology and anatomy.Office of Naval Research (N00014-92-J-1309, N00014-93-1-1364, N0014-95-1-0409

    Prediction of antibiotic mass flows in urban catchments and their environmental prioritization

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    Urban emissions of antibiotics into the environment have the potential to adversely affect terrestrial and aquatic organisms. Developed standardized test methods allow the quantification of the resulting ecotoxicological risk, which strongly relies on a comprehensive situation analysis by predicting or measuring a representative antibiotic concentration of interest. Predicting the input loads of antibiotics to wastewater treatment plants using secondary input data (e.g. prescriptions) is a reasonable method if no analytical data is available. The absence of such data poses the question of an aquired reasonable sample quantity to capture local seasonal differences in prescriptions as well as flow conditions within the catchment area. Both, the theoretical and measurement based determination of environmental concentrations have been scarcely verified in practice. Hence, high resolution prescription data in combination with an extensive monitoring campaign at the wastewater treatment plant Dresden-Kaditz (WWTP) were used as a basis to evaluate the reliability of predicting and measuring urban antibiotic emissions. As expected, the recovery of antibiotic input loads strongly varies among substances. The group of macrolides as well as sulfamethoxazole and trimethoprim were almost fully recovered whereas nearly all substances of the beta-lactam family exhibit high elimination rates during the wastewater transport in the sewer system. Yet other antibiotics (e.g. fluoroquinolones) show distinct fluctuations through the year, which was not obvious from relatively constant prescriptions. The latter substances are an example that available data are not per se sufficient to predict the actual release into the environment which, in certain cases, emphasizes the necessity of adequate measuring campaings. The extensive data pool of this study was hence used to calculate the necessary number of samples to determine a representative annual mean load to the WWTP. Based on the applied approach, a minimum number of 20 to 40 samples per year is proposed to reasonably estimate a representative annual input load of antibiotics and other micropollutants. Regarding the WWTP, the mass flow analysis revealed that macrolides, clindamycin/ clindamycin-sulfoxide and trimethoprim were mainly released with the effluent, while penicillins, cephalosporins as well as sulfamethoxazole were partly degraded in the studied WWTP. Levofloxacin and ciprofloxacin are the only antibiotics under investigation with a significant mass fraction bound to primary, excess and digested sludge. In this context, the sludge concentrations are considered to be highly inconsistent which leads to questionable results. It remains unclear whether the inconsistencies are due to insufficiencies in sampling and/or analytical determination or if the fluctuations can be considered reasonable for digesters. Subsequently, verified antibiotic loads were evaluated regarding their ecotoxicological effects in the aquatic environment. Two approaches were applied (1) to address the ecological impact on individual trophic levels algae, daphnia and fish, and (2) to assess the possible synergistic potential of antibiotic combinations. Ciprofloxacin, levofloxacin and the group of cephalosporins showed to significantly affect the aquatic environment. They either have the highest impact on (one of) the lowest trophic level(s) or disproportionately increase the ecotoxicological risk due to their synergistic characteristics. In this regard, the deficiencies regarding the input prediction of these antibiotics is of particular concern. The underestimation of such critical mass flow conditions weakens the approach of assessing environmental risks on the basis of secondary data like prescriptions. Hence, efforts must be made to further develop the projection model by improving the quality of secondary data, identifying additional emitters and understanding possible retention and degradation dynamics of antibiotics within the sewer system.:Abstract 2 Danksagung 1 Table of Contents 1 Chapter 1 – Introduction 1 Scope 1 Goals and structure 3 Approach and Methods 5 Chapter 2 – Representative input load of antibiotics to WWTPs: Predictive accuracy and determination of a required sampling quantity 11 Introduction 14 Materials and Methods 16 Results and discussion 24 Conclusion 38 References 39 Chapter 3 – Mass flow of antibiotics in a wastewater treatment plant focusing on removal variations due to operational parameters 41 Introduction 45 Materials and Methods 47 Results and discussion 52 Conclusions 65 References 66 Chapter 4 – Species-related risk assessment of antibiotics using the probability distribution of long-term toxicity data as weighting function – a case study 71 Introduction 74 Materials and Methods 75 Results and discussion 86 Conclusions and summary 93 References 95 Chapter 5 – Environmental risk assessment of antibiotics including synergistic and antagonistic combination effects 99 Materials and Methods 104 Results 113 Discussion 120 Conclusions and summary . 125 References 126 Chapter 6 – Results and conclusions 129 Individual results 131 Aggregation of results 133 Final conclusions 134 References 139 Annex 1 – Supplementary material Chapter 2 141 Annex 2 – Supplementary material Chapter 3 147 Annex 3 – Supplementary material Chapter 4 159 Annex 4 – Supplementary material Chapter 5 177In der Humanmedizin eingesetzte Antibiotika werden im menschlichen Körper nicht vollstĂ€ndig metabolisiert und gelangen ĂŒber die Ausscheidungen in das kommunale Abwasser. In der KlĂ€ranlage erfolgt nur eine unvollstĂ€ndige Elimination dieser Stoffe, so dass der KlĂ€ranlagenablauf einen Hot Spot fĂŒr Antibiotikaemissionen in die Umwelt darstellt. Das induzierte ökotoxikologische Risiko kann anhand standardisierter Testverfahren und allgemein anerkannter BewertungsansĂ€tze fĂŒr Einzelsubstanzen abgeschĂ€tzt werden. Erfolgt jedoch die Betrachtung von Antibiotikagemischen, wie es fĂŒr den gereinigten Ablauf einer KlĂ€ranlage sinnvoll ist, sind aufgrund zumeist unspezifischer Wirkmechanismen und dem Mangel an reprĂ€sentativen Daten eine Reihe von Vereinfachungen und Annahmen zu treffen. Es besteht in der Folge die Gefahr einer UnterschĂ€tzung des durch Substanzgemische hervorgerufenen ökotoxikologischen Risikos. Eine vielversprechende Möglichkeit den Entscheidungsprozess ĂŒber mögliche Vermeidungs- und Eliminationsmaßnahmen zu unterstĂŒtzen besteht in der Priorisierung von Antibiotika entsprechend ihres Effektpotentials. Hierbei sind Substanzen zu identifizieren, die den grĂ¶ĂŸten Einfluss auf die Nahrungskette im GewĂ€sser bzw. das höchste (negative) Synergiepotential mit anderen Substanzen aufweisen. Die Verringerung dieser Substanzen fĂŒhrt zu einer hohen ökologischen EffektivitĂ€t und Effizienz der eingesetzten Mittel. Wie im Fall des klassischen Bewertungsansatzes, ist auch fĂŒr den Priorisierungsansatz eine umfĂ€ngliche und zuverlĂ€ssige Situationsanalyse die Grundvoraussetzung fĂŒr verwertbare Ergebnisse. Die Situationsanalyse beruht auf der analytischen Bestimmung bzw. der AbschĂ€tzung von emittierten Antibiotikafrachten zur Berechnung von reprĂ€sentativen Umweltkonzentrationen. Analytisch ermittelte Umweltkonzentrationen vieler Antibiotika weisen aufgrund saisonaler Verschreibungsmuster eine hohe zeitliche und rĂ€umliche VariabilitĂ€t auf. Die fĂŒr eine adĂ€quate Erfassung der Situation notwendigen Messkampagnen sind kostenintensiv, wobei die tatsĂ€chlich notwendige HĂ€ufigkeit der Probenahme von zumeist nicht hinreichend bekannten substanzspezifischen Informationen, wie der chemischen StabilitĂ€t im Rohabwasser und der saisonal beeinflussten Applikation, abhĂ€ngt. Alternativ können AntibiotikaeintrĂ€ge in die Kanalisation anhand von Verschreibungsdaten abgeschĂ€tzt und mit Hilfe von Stoffflussanalysen (SFA) zur ökotoxikologischen Bewertung herangezogen werden. Eine vom Umfang befriedigende, direkte GegenĂŒberstellung von prognostizierten und analytisch ermittelten Frachten ist bisher jedoch nicht erfolgt, so dass die Verifizierung dieses Ansatzes noch aussteht. FĂŒr den Fall einer bestehenden Verschreibungspflicht fĂŒr Antibiotika besitzen Verschreibungsdaten eine vergleichsweise hohe zeitliche und rĂ€umliche InformationsgĂŒte. In Verbindung mit einer an diese DatenqualitĂ€t angepassten Messkampagne, ergibt sich die Möglichkeit einer detaillierten SFA mit substanzspezifischer Bewertung der Eignung des Prognoseansatzes. Die am Beispiel der Stadt Dresden durchgefĂŒhrte Bewertung des Prognoseansatzes fußt auf einer 15-monatigen Messkampagne und den fĂŒr das Einzugsgebiet der ZentralklĂ€ranlage Dresden-Kaditz verfĂŒgbaren Verschreibungsdaten der AOK PLUS. ErwartungsgemĂ€ĂŸ ergibt der Abgleich von erwarteten und analytisch ermittelten Frachten eine starke Variation der fĂŒr den Zulauf der KlĂ€ranlage ermittelten Wiederfindungsdaten verschiedener Substanzen. Die analytisch ermittelten Frachten von Sulfamethoxazol, Trimethoprim sowie der Gruppe der Makrolid-Antibiotika entsprechen nahezu den prognostizierten Mengen. Die Beta-Laktam-Antibiotika unterliegen bereits wĂ€hrend des Abwassertransports einer umfĂ€nglichen, zumeist biologisch bedingten, Elimination, was zu hohen Unterbefunden im Zulauf der KlĂ€ranlage fĂŒhrt. Andere Substanzen hingegen (z.B. Fluorchinolone) weisen messtechnisch eine signifikante Jahresdynamik auf, die aufgrund der weitgehend konstanten Verschreibung in dieser AusprĂ€gung nicht zu erwarten ist. Die Auswertung zuletzt genannter Substanzen zeigt deutlich, dass die Nutzung von Verschreibungsdaten nicht per se ausreicht, um die Emission von Antibiotika (und anderer Pharmazeutika) sowie die sich daraus ergebenden Umweltkonzentrationen mit ausreichender Sicherheit prognostizieren zu können. FĂŒr eine nachgelagerte ökotoxikologische Bewertung ist in diesen FĂ€llen die DurchfĂŒhrung von Messungen unumgĂ€nglich. Zur effizienten Planung derartiger Kampagnen wurde der umfassende Datenpool dieser Studie hinsichtlich der erforderlichen Probenanzahl zur Bestimmung einer reprĂ€sentativen mittleren Jahresfracht ausgewertet. Es ergibt sich ein Minimum von 20 bis 40 homogen ĂŒber das Jahr verteilten Proben, um die jĂ€hrlich in die KlĂ€ranlage eingetragene Fracht an Antibiotika bzw. anderer Mikroschadstoffe mit ausreichender Sicherheit abschĂ€tzen zu können. Im Rahmen der SFA in der KlĂ€ranlage Dresden-Kaditz wird deutlich, dass Makrolide, Clindamycin und dessen Humanmetabolit Clindamycin-Sulfoxid sowie Trimethoprim in der nahezu keiner Elimination unterliegen, wohingegen Penizilline, Cefalosporine und auch Sulfamethoxazol teilweise bis vollstĂ€ndig abgebaut werden. Mit Levofloxacin und Ciprofloxacin handelt es sich um die einzigen untersuchten Antibiotika, welche zu einem signifikanten Massenanteil an PrimĂ€r-, Überschuss- und Faulschlamm gebunden vorgefunden werden. Aufgrund der hohen Relevanz dieses Eliminationspfades fĂŒr die zuvor genannten Antibiotika bedarf die Beobachtung von z. T. widersprĂŒchlichen Schwankungen einer kritischen Betrachtung der Ergebnisse. Es ist nicht abschließend geklĂ€rt, ob die beobachteten Fluktuationen auf eine unzureichende QualitĂ€t der Probenahme und/oder der Analytik zurĂŒckzufĂŒhren sind oder sich die Schwankungen in einem fĂŒr FaulbehĂ€lter tolerierbaren Bereich befinden. Im Anschluss an die verifizierten Antibiotikaemissionen erfolgte die Priorisierung der betrachteten Antibiotika nach ihrem ökotoxikologischen Effektpotential. Zum einen wurde der ökologische Einfluss auf verschiedene, die Nahrungskette bildende trophische Ebenen (Alge, Daphnie, Fisch) untersucht. In Anlehnung an die humanmedizinische Kombinationstherapie erfolgte im zweiten Ansatz die Beurteilung der Antibiotika hinsichtlich ihres möglichen Potentials zur VerstĂ€rkung von negativen Effekten durch das gleichzeitige Auftreten mit anderen Substanzen. FĂŒr Ciprofloxacin, Levofloxacin und die Gruppen der Makrolide und Cefalosporine konnten signifikante BeeintrĂ€chtigungen der aquatischen Umwelt nachgewiesen werden. Diese Stoffe und Stoffgruppen fĂŒhrten im Rahmen der untersuchten Substanzen entweder zur höchsten Schadwirkung gegenĂŒber der niedrigsten trophischen Ebene oder besitzen das höchste Synergiepotential in Kombination mit anderen Substanzen. Die Auswertung der SFA bestĂ€tigt die grundsĂ€tzliche Eignung der Verschreibungsdaten sowie des entwickelten Prognosemodells zur Vorhersage von Antibiotikaemissionen im urbanen Raum. Die Stoffflussanalyse stellt somit ein strategisches, im Vergleich zur Messung kostengĂŒnstiges Instrument zur Identifikation von Hot Spots der Antibiotikaemission dar und erleichtert die Entscheidungsfindung fĂŒr monetĂ€r aufwendige Reduktionsmaßnahmen am Ort der Entstehung oder in der KlĂ€ranlage (z.B. 4. Reinigungsstufe). Die Vorgehensweise zur Priorisierung von Substanzen hinsichtlich ihres ökotoxikologischen Effektpotentials eignet sich sehr gut, Antibiotika mit dem höchsten Schadpotential zu identifizieren. Die Verschneidung der Kenntnis dieser Substanzen mit den Ergebnissen der SFA macht deutlich, dass mit Ausnahme der Makrolide, alle ökotoxikologisch priorisierten Antibiotika eine mangelhafte PrognosefĂ€higkeit aufweisen. Die unvollstĂ€ndige Abbildung kritischer Stoffströme, wie z.B. Frachtspitzen, fĂŒhrt insbesondere im Fall der ökotoxikologisch priorisierten Substanzen zu einer Minderung der Aussagekraft des auf Verschreibungsdaten beruhenden Prognoseansatzes. An diesem Punkt ist in zukĂŒnftigen Betrachtungen anzusetzen, um die QualitĂ€t von Verschreibungsdaten zu verbessern, potentiell nicht erfasste Emittenten in die Betrachtungen einzubeziehen, sowie die Dynamik der RĂŒckhalte- und Eliminationsprozesse in der Kanalisation adĂ€quat beschreiben zu können. Die ergĂ€nzende Betrachtung weiterer Anlagentechnologien (z.B. Festbettreaktoren) kann zur BestĂ€tigung der am Beispiel der KlĂ€ranlage Dresden-Kaditz gewonnenen Ergebnisse beitragen bzw. Unterschiede bei der Elimination von Antibiotika das Potential, die Problematik der Antibiotika und anderer Mikroschadstoffe bereits wĂ€hrend der Planung von Abwasseranlagen berĂŒcksichtigen zu können.:Abstract 2 Danksagung 1 Table of Contents 1 Chapter 1 – Introduction 1 Scope 1 Goals and structure 3 Approach and Methods 5 Chapter 2 – Representative input load of antibiotics to WWTPs: Predictive accuracy and determination of a required sampling quantity 11 Introduction 14 Materials and Methods 16 Results and discussion 24 Conclusion 38 References 39 Chapter 3 – Mass flow of antibiotics in a wastewater treatment plant focusing on removal variations due to operational parameters 41 Introduction 45 Materials and Methods 47 Results and discussion 52 Conclusions 65 References 66 Chapter 4 – Species-related risk assessment of antibiotics using the probability distribution of long-term toxicity data as weighting function – a case study 71 Introduction 74 Materials and Methods 75 Results and discussion 86 Conclusions and summary 93 References 95 Chapter 5 – Environmental risk assessment of antibiotics including synergistic and antagonistic combination effects 99 Materials and Methods 104 Results 113 Discussion 120 Conclusions and summary . 125 References 126 Chapter 6 – Results and conclusions 129 Individual results 131 Aggregation of results 133 Final conclusions 134 References 139 Annex 1 – Supplementary material Chapter 2 141 Annex 2 – Supplementary material Chapter 3 147 Annex 3 – Supplementary material Chapter 4 159 Annex 4 – Supplementary material Chapter 5 17

    US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report

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    This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference

    Human Resources Investment through the Scholarship Program Implementation for Sustainable Development in the Local Region

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    Bojonegoro is the region that contributes 30 percent of national oil, so it is hoped that natural resources can be converted into human resources which are sustainable development investments, looking at the future of Bojonegoro Regency from the HDI perspective to achieve the largest target, whether the policy about scholarships taken has full implications for sustainable development, the researcher is using the Double Exponential Smoothing method. Data were obtained from the Regional Development Planning Agency and the Statistics of Bojonegoro report. Based on the calculation results, the best forecasting is obtained based on the measurement accuracy value of 0.7 MAPE  0.385 persen means that its very good criteria, with many scholarship programs from 2019-2021, concludin using qualitative methods plus 2022 Village RPL scholarships with the number of thousands of people, after graduating in 2024 IPM Bojonegoro is predicted to enter the high category, namely the highest score of 72.08 even more, as an outcome of the program it can be practiced because it is intended for stakeholders and structural drivers of villages in Bojonegoro, and this is in line with sustainable development

    Production Engineering and Management

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    The annual International Conference on Production Engineering and Management takes place for the sixth time his year, and can therefore be considered a well - established event that is the result of the joint effort of the OWL University of Applied Sciences and the University of Trieste. The conference has been established as an annual meeting under the Double Degree Master Program ‘Production Engineering and Management’ by the two partner universities. The main goal of the conference is to provide an opportunity for students, researchers and professionals from Germany, Italy and abroad, to meet and exchange information, discuss experiences, specific practices and technical solutions used in planning, design and management of production and service systems. In addition, the conference is a platform aimed at presenting research projects, introducing young academics to the tradition of Symposiums and promoting the exchange of ideas between the industry and the academy. Especially the contributions of successful graduates of the Double Degree Master Program ‘Production Engineering and Management’ and those of other postgraduate researchers from several European countries have been enforced. This year’s special focus is on Direct Digital Manufacturing in the context of Industry 4.0, a topic of great interest for the global industry. The concept is spreading, but the actual solutions must be presented in order to highlight the practical benefits to industry and customers. Indeed, as Henning Banthien, Secretary General of the German ‘Plattform Industrie 4.0’ project office, has recently remarked, “Industry 4.0 requires a close alliance amongst the private sector, academia, politics and trade unions” in order to be “translated into practice and be implemented now”. PEM 2016 takes place between September 29 and 30, 2016 at the OWL University of Applied Sciences in Lemgo. The program is defined by the Organizing and Scientific Committees and clustered into scientific sessions covering topics of main interest and importance to the participants of the conference. The scientific sessions deal with technical and engineering issues, as well as management topics, and include contributions by researchers from academia and industry. The extended abstracts and full papers of the contributions underwent a double - blind review process. The 24 accepted presentations are assigned, according to their subject, to one of the following sessions: ‘Direct Digital Manufacturing in the Context of Industry 4.0’, ‘Industrial Engineering and Lean Management’, ‘Management Techniques and Methodologies’, ‘Wood Processing Technologies and Furniture Production’ and ‘Innovation Techniques and Methodologies
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