7,348 research outputs found
Generalizations of Tucker-Fan-Shashkin lemmas
Tucker and Ky Fan's lemma are combinatorial analogs of the Borsuk-Ulam
theorem (BUT). In 1996, Yu. A. Shashkin proved a version of Fan's lemma, which
is a combinatorial analog of the odd mapping theorem (OMT). We consider
generalizations of these lemmas for BUT-manifolds, i.e. for manifolds that
satisfy BUT. Proofs rely on a generalization of the OMT and on a lemma about
the doubling of manifolds with boundaries that are BUT-manifolds.Comment: 10 pages, 2 figure
AN APPROACH TO CREATING A SIMPLE DIGITAL TWIN FOR OPTIMIZING A SMALL ELECTRIC CONCEPT VEHICLE DRIVETRAIN
Since modeling and simulation are integral tools in engineering, the question is not if they should be used in a design process, but rather how they should be used to deliver the best solutions. The objective of this pa-per is to outline an approach to creating a simple Digi-tal Twin for a small electric vehicle drivetrain utilizing only parametric 3D CAD models, widely used simu-lation tools and some programming libraries. First, the concept of the Digital Twin, its benefits, then the possibilities of using Generative Design are briefly in-troduced, afterwards electric vehicles’ advantages are reviewed. In an example project the properties and opportunities of the 3D CAD- and simulation models are demonstrated. Finally, future improvements and automated optimization opportunities are discussed.Da Modellierung und Simulation integrale Werkzeuge im Ingenieurwesen sind, stellt sich nicht die Frage, ob sie in einem Entwurfsprozess eingesetzt werden sollten, sondern vielmehr, wie sie verwendet werden sollten, um die besten Lösungen zu liefern. Ziel dieses Artikels ist es, einen Ansatz zur Erstellung eines einfachen Digi-tal Twin für den Antriebsstrang eines kleinen Elektrofahrzeugs zu skizzieren, bei dem nur parametrische 3D-CAD-Modelle, weit verbreitete Simulationswerkzeuge und einige Programmierbibliotheken verwendet werden. Zuerst wird das Konzept des Digitalen Zwillings, seine benefits, dann die Möglichkeiten der Nutzung des Generativen Designs briefly vorgestellt, danach werden die Vorteile von Elektrofahrzeugen überprüft. In einem Beispielprojekt werden die Eigenschaften und Möglichkeiten der 3D-CAD- und Simulationsmodelle demonstriert. Abschließend werden zukünftige Verbesserungen und automatisierte Optimierungsmöglichkeiten diskutiert
Comparative effects of some medicinal plants on blood glucose concentration and lipid levels in alloxaninduced diabetic rats
The comparative effects of the chloroform extracts of the leaves of Psidium guajava (Myrtaceae), Anacardium occidentale (Anacardiaceae) and Eucalyptus globulus (Myrtaceae) and fruits of Xylopia aethiopica (Annonaceae) on blood glucose concentration and lipid levels of diabetic rats were investigated using standard methods. The results show 74, 82 and 83% reductions in the blood glucose concentrations upon the administration of A. occidentale (100 mg/kg body weight), E. globulus (100mg/kg body weight) and X. aethiopica (250 mg/kg body weight) extracts respectively as from the 10th hour of treatments in relation to the 74 and 69% reductions in glibenclamide and diabetic untreated groups respectively while the synergic treatment group [A. occidentale + E. globulus (100 mg/kg body weight)] showed 83% decrease in the blood glucose concentration as from the 10th hour upon the administration of the combined extracts when compared with the values obtained for the glibenclamide and diabetic untreated groups. P. guajava extract had the greatest significant (p<0.05) reduction in the total cholesterol concentration of the treated rats. P. guajava + X. aethiopica treatment group in a similar manner showed the most significant (p<0.05) decrease in the triglyceride concentration of the treated rats. Hence, the individual performances of these extracts on blood glucose concentration and blood lipids confirm their ability to reduce blood glucose and diabetic complications.Key words: Chloroform extract, Psidium guajava (Myrtaceae), Anacardium occidentale (Anacardiaceae), Eucalyptus globulus (Myrtaceae), Xylopia aethiopica (Annonaceae)
Tracking a city’s center of gravity over 500 years of growth from a time series of georectified historical maps
\ua9 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. It is surprising difficult to define where a city center lies, yet its location has a profound effect on a city’s structure and function. We examine whether city center typicality points can be consistently located on historical maps such that their centroid identifies a meaningful central location over a 500-year period in Southampton, UK. We compare movements of this city center centroid against changes in the geographical center of the city as defined by its boundary. Southampton’s historical maps were georectified with a mean accuracy of 21 m (range 9.9 to 47 m), and 18 to 102 typicality points were identified per map, enough to chart changes in the city center centroid through time. Over nearly 500 years, Southampton’s center has moved just 343 m, often corresponding with the key retail attractants of the time, while its population has increased 80-fold, its administrative area 60-fold and its geographical center moved 1985 m. This inertia to change in the city center presents environmental challenges for the present-day, made worse by the geography of Southampton, bounded by the sea, rivers and major roads. Geographical context, coupled with planning decisions in the past that maintain a city center in its historical location, place limits on the current sustainability of a city
Anticoagulation in simultaneous pancreas kidney transplantation - On what basis?
BACKGROUND: Despite technical refinements, early pancreas graft loss due to thrombosis continues to occur. Conventional coagulation tests (CCT) do not detect hypercoagulability and hence the hypercoagulable state due to diabetes is left untreated. Thromboelastogram (TEG) is an in-vitro diagnostic test which is used in liver transplantation, and in various intensive care settings to guide anticoagulation. TEG is better than CCT because it is dynamic and provides a global hemostatic profile including fibrinolysis. AIM: To compare the outcomes between TEG and CCT (prothrombin time, activated partial thromboplastin time and international normalized ratio) directed anticoagulation in simultaneous pancreas and kidney (SPK) transplant recipients. METHODS: A single center retrospective analysis comparing the outcomes between TEG and CCT-directed anticoagulation in SPK recipients, who were matched for donor age and graft type (donors after brainstem death and donors after circulatory death). Anticoagulation consisted of intravenous (IV) heparin titrated up to a maximum of 500 IU/h based on CCT in conjunction with various clinical parameters or directed by TEG results. Graft loss due to thrombosis, anticoagulation related bleeding, radiological incidence of partial thrombi in the pancreas graft, thrombus resolution rate after anticoagulation dose escalation, length of the hospital stays and, 1-year pancreas and kidney graft survival between the two groups were compared. RESULTS: Seventeen patients who received TEG-directed anticoagulation were compared against 51 contemporaneous SPK recipients (ratio of 1: 3) who were anticoagulated based on CCT. No graft losses occurred in the TEG group, whereas 11 grafts (7 pancreases and 4 kidneys) were lost due to thrombosis in the CCT group (P = 0.06, Fisher's exact test). The overall incidence of anticoagulation related bleeding (hematoma/ gastrointestinal bleeding/ hematuria/ nose bleeding/ re-exploration for bleeding/ post-operative blood transfusion) was 17.65% in the TEG group and 45.10% in the CCT group (P = 0.05, Fisher's exact test). The incidence of radiologically confirmed partial thrombus in pancreas allograft was 41.18% in the TEG and 25.50% in the CCT group (P = 0.23, Fisher's exact test). All recipients with partial thrombi detected in computed tomography (CT) scan had an anticoagulation dose escalation. The thrombus resolution rates in subsequent scan were 85.71% and 63.64% in the TEG group vs the CCT group (P = 0.59, Fisher's exact test). The TEG group had reduced blood product usage {10 packed red blood cell (PRBC) and 2 fresh frozen plasma (FFP)} compared to the CCT group (71 PRBC/ 10 FFP/ 2 cryoprecipitate and 2 platelets). The proportion of patients requiring transfusion in the TEG group was 17.65% vs 39.25% in the CCT group (P = 0.14, Fisher's exact test). The median length of hospital stay was 18 days in the TEG group vs 31 days in the CCT group (P = 0.03, Mann Whitney test). The 1-year pancreas graft survival was 100% in the TEG group vs 82.35% in the CCT group (P = 0.07, log rank test) and, the 1-year kidney graft survival was 100% in the TEG group vs 92.15% in the CCT group (P = 0.23, log tank test). CONCLUSION: TEG is a promising tool in guiding judicious use of anticoagulation with concomitant prevention of graft loss due to thrombosis, and reduces the length of hospital stay
Superpixel-based Two-view Deterministic Fitting for Multiple-structure Data
This paper proposes a two-view deterministic geometric model fitting method,
termed Superpixel-based Deterministic Fitting (SDF), for multiple-structure
data. SDF starts from superpixel segmentation, which effectively captures prior
information of feature appearances. The feature appearances are beneficial to
reduce the computational complexity for deterministic fitting methods. SDF also
includes two original elements, i.e., a deterministic sampling algorithm and a
novel model selection algorithm. The two algorithms are tightly coupled to
boost the performance of SDF in both speed and accuracy. Specifically, the
proposed sampling algorithm leverages the grouping cues of superpixels to
generate reliable and consistent hypotheses. The proposed model selection
algorithm further makes use of desirable properties of the generated
hypotheses, to improve the conventional fit-and-remove framework for more
efficient and effective performance. The key characteristic of SDF is that it
can efficiently and deterministically estimate the parameters of model
instances in multi-structure data. Experimental results demonstrate that the
proposed SDF shows superiority over several state-of-the-art fitting methods
for real images with single-structure and multiple-structure data.Comment: Accepted by European Conference on Computer Vision (ECCV
Mollusca from a species-rich deep-water Leptometra community in the Alboran Sea
Postprint1,006
A decade of letrozole: FACE
Third-generation nonsteroidal aromatase inhibitors (AIs), letrozole and anastrozole, are superior to tamoxifen as initial therapy for early breast cancer but have not been directly compared in a head-to-head adjuvant trial. Cumulative evidence suggests that AIs are not equivalent in terms of potency of estrogen suppression and that there may be differences in clinical efficacy. Thus, with no data from head-to-head comparisons of the AIs as adjuvant therapy yet available, the question of whether there are efficacy differences between the AIs remains. To help answer this question, the Femara versus Anastrozole Clinical Evaluation (FACE) is a phase IIIb open-label, randomized, multicenter trial designed to test whether letrozole or anastrozole has superior efficacy as adjuvant treatment of postmenopausal women with hormone receptor (HR)- and lymph node-positive breast cancer. Eligible patients (target accrual, N = 4,000) are randomized to receive either letrozole 2.5 mg or anastrozole 1 mg daily for up to 5 years. The primary objective is to compare disease-free survival at 5 years. Secondary end points include safety, overall survival, time to distant metastases, and time to contralateral breast cancer. The FACE trial will determine whether or not letrozole offers a greater clinical benefit to postmenopausal women with HR+ early breast cancer at increased risk of early recurrence compared with anastrozole
Optically trapped bacteria pairs reveal discrete motile response to control aggregation upon cell–cell approach
Aggregation of bacteria plays a key role in the formation of many biofilms. The critical first step is cell–cell approach, and yet the ability of bacteria to control the likelihood of aggregation during this primary phase is unknown. Here, we use optical tweezers to measure the force between isolated Bacillus subtilis cells during approach. As we move the bacteria towards each other, cell motility (bacterial swimming) initiates the generation of repulsive forces at bacterial separations of ~3 μm. Moreover, the motile response displays spatial sensitivity with greater cell–cell repulsion evident as inter-bacterial distances decrease. To examine the environmental influence on the inter-bacterial forces, we perform the experiment with bacteria suspended in Tryptic Soy Broth, NaCl solution and deionised water. Our experiments demonstrate that repulsive forces are strongest in systems that inhibit biofilm formation (Tryptic Soy Broth), while attractive forces are weak and rare, even in systems where biofilms develop (NaCl solution). These results reveal that bacteria are able to control the likelihood of aggregation during the approach phase through a discretely modulated motile response. Clearly, the force-generating motility we observe during approach promotes biofilm prevention, rather than biofilm formation
Proceso de construcci?n de una cultura de paz en los ni?os de transici?n de la instituci?n educativa Armando Romero Lozano de Sevilla Valle, a trav?s de estrategias did?cticas sensibilizadoras
121 p. Recurso Electr?nicoEl presente proyecto de investigaci?n ?proceso de construcci?n de una cultura de paz en los ni?os de preescolar, a trav?s de estrategias did?cticas sensibilizadoras? consiste en visibilizar los alcances en la mejora de las habilidades de resoluci?n de conflictos a trav?s de actividades l?dicas y art?sticas en los ni?os de preescolar de Instituci?n Educativa Armando Romero Lozano del municipio de Sevilla valle.
Todo esto se realiz? partiendo del planteamiento de los objetivos, los cuales permitir?n lograr su cometido; en primer lugar, identificar a partir de los resultados qu? problem?ticas de comportamiento tienen los ni?os, en segundo lugar, implementar un plan de intervenci?n orientado a mejorar las relaciones interpersonales de los ni?os y en tercer lugar, evaluar el impacto generado con el plan de intervenci?n propuesto para tal fin.
En cuanto al marco te?rico, se busc? el soporte en los postulados de diferentes autores, los cuales resultaron pertinentes para el abordaje conceptual de este, ya que hablan del desarrollo de la capacidad creadora, principios, normas y valores que hacen un clima escolar acorde para una educaci?n para la paz y una participaci?n democr?tica, como aspectos importantes a tener en cuenta en esta investigaci?n.
Respecto a la metodolog?a, se desarroll? en base a la investigaci?n la investigaci?n acci?n-participativa y cooperativa, con un enfoque etnogr?fico, dentro del paradigma cualitativo. Tras esto, el resultado que se obtendr? del proceso estudiado, que junto a referentes te?ricos ayuda a explicar los procesos de la pr?ctica escolar estudiada.This research project process of building a culture of peace in preschool children through teaching strategies visible sensitizer is the scope in improving the skills of conflict resolution through recreational and artistic activities preschoolers educational institution Armando Romero Lozano the municipality of Seville valley.
All this was done based on the approach of objectives, which will allow achieve its mission; first identified from the results which problematic behavior have children, secondly, implement an intervention plan aimed at improving interpersonal relationships of children and thirdly, to assess the impact generated with the intervention plan proposed for this purpose.
As for the theoretical framework, support the propositions of different authors, which were relevant to the conceptual approach to this is sought, as they speak of the development of creativity, principles, norms and values that make a chord school climate for education for peace and democratic participation, as important aspects to consider in this research.
Reading methodology was developed based on the research-participatory and cooperative action with an ethnographic approach, within the qualitative research paradigm. After this, the result you get the process under study, which together with theoretical framework helps explain the processes studied school practice
Keywords: skills, peace, transition, norms, values and family
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