bluuebunny/crossref_metadata_2025_split huggingface dataset:
Freeform Honeycomb Structures
Authors: Jiang Caigui , Wang Jun , Wallner Johannes , Pottmann Helmut 
Published: August 2014

AbstractMotivated by requirements of freeform architecture, and inspired by the geometry of hexagonal combs in beehives, this paper addresses torsion‐free structures aligned with hexagonal meshes. Since repetitive geometry is a very important contribution to the reduction of production costs, we study in detail “honeycomb structures”, which are defined as torsion‐free structures where the walls of cells meet at 120 degrees. Interestingly, the Gauss‐Bonnet theorem is useful in deriving information on the global distribution of node axes in such honeycombs. This paper discusses the computation and modeling of honeycomb structures as well as applications, e.g. for shading systems, or for quad meshing. We consider this paper as a contribution to the wider topic of freeform patterns, polyhedral or otherwise. Such patterns require new approaches on the technical level, e.g. in the treatment of smoothness, but they also extend our view of what constitutes aesthetic freeform geometry.
A Variational Taxonomy for Surface Reconstruction from Oriented Points
Authors: Schroers C. , Setzer S. , Weickert J. 
Published: August 2014

AbstractThe problem of reconstructing a watertight surface from a finite set of oriented points has received much attention over the last decades. In this paper, we propose a general higher order framework for surface reconstruction. It is based on the idea that position and normal defined by each oriented point can be used to construct an implicit local description of the unknown surface. On the one hand, this allows us to systematically explain and relate several popular methods, for example implicit moving least squares, smooth signed distance surface reconstruction as well as (screened) Poisson surface reconstruction. On the other hand, it allows to derive and discuss a number of new approaches for reconstructing either the signed distance or the indicator function of the sought object. All of these approaches are able to achieve competitive results but one of them turns out to be especially promising. To improve reconstructions in difficult real world scenarios where point clouds have been estimated from colour images, we introduce a hull constraint that encourages the surface to stay within a given region. Our framework is implemented on the GPU using a recent cyclic scheme called Fast Jacobi, which combines low implementational effort with high efficiency.
Semi‐sharp Creases on Subdivision Curves and Surfaces
Authors: Kosinka J. , Sabin M. A. , Dodgson N. A. 
Published: August 2014

AbstractWe explore a method for generalising Pixar semi‐sharp creases from the univariate cubic case to arbitrary degree subdivision curves. Our approach is based on solving simple matrix equations. The resulting schemes allow for greater flexibility over existing methods, via control vectors. We demonstrate our results on several high‐degree univariate examples and explore analogous methods for subdivision surfaces.
Pseudo‐Spline Subdivision Surfaces
Authors: Deng Chongyang , Hormann Kai 
Published: August 2014

AbstractPseudo‐splines provide a rich family of subdivision schemes with a wide range of choices that meet various demands for balancing the approximation power, the length of the support, and the regularity of the limit functions. Special cases of pseudo‐splines include uniform odd‐degree B‐splines and the interpolatory 2n‐point subdivision schemes, and the other pseudo‐splines fill the gap between these two families. In this paper we show how the refinement step of a pseudo‐spline subdivision scheme can be implemented efficiently using repeated local operations, which require only the data in the direct neighbourhood of each vertex, and how to generalize this concept to quadrilateral meshes with arbitrary topology. The resulting pseudo‐spline surfaces can be arbitrarily smooth in regular mesh regions and C1 at extraordinary vertices as our numerical analysis reveals.
Functional Fluids on Surfaces
Authors: Azencot Omri , Weißmann Steffen , Ovsjanikov Maks , Wardetzky Max , Ben‐Chen Mirela 
Published: August 2014

AbstractFluid simulation plays a key role in various domains of science including computer graphics. While most existing work addresses fluids on bounded Euclidean domains, we consider the problem of simulating the behavior of an incompressible fluid on a curved surface represented as an unstructured triangle mesh. Unlike the commonly used Eulerian description of the fluid using its time‐varying velocity field, we propose to model fluids using their vorticity, i.e., by a (time varying) scalar function on the surface. During each time step, we advance scalar vorticity along two consecutive, stationary velocity fields. This approach leads to a variational integrator in the space continuous setting. In addition, using this approach, the update rule amounts to manipulating functions on the surface using linear operators, which can be discretized efficiently using the recently introduced functional approach to vector fields. Combining these time and space discretizations leads to a conceptually and algorithmically simple approach, which is efficient, time‐reversible and conserves vorticity by construction. We further demonstrate that our method exhibits no numerical dissipation and is able to reproduce intricate phenomena such as vortex shedding from boundaries.
Exploring the Geometry of the Space of Shells
Authors: Heeren B. , Rumpf M. , Schröder P. , Wardetzky M. , Wirth B. 
Published: August 2014

AbstractWe prove both in the smooth and discrete setting that the Hessian of an elastic deformation energy results in a proper Riemannian metric on the space of shells (modulo rigid body motions). Based on this foundation we develop a time‐ and space‐discrete geodesic calculus. In particular we show how to shoot geodesics with prescribed initial data, and we give a construction for parallel transport in shell space. This enables, for example, natural extrapolation of paths in shell space and transfer of large nonlinear deformations from one shell to another with applications in animation, geometric, and physical modeling. Finally, we examine some aspects of curvature on shell space.
As‐Conformal‐As‐Possible Surface Registration
Authors: Yoshiyasu Yusuke , Ma Wan‐Chun , Yoshida Eiichi , Kanehiro Fumio 
Published: August 2014

AbstractWe present a non‐rigid surface registration technique that can align surfaces with sizes and shapes that are different from each other, while avoiding mesh distortions during deformation. The registration is constrained locally as conformal as possible such that the angles of triangle meshes are preserved, yet local scales are allowed to change. Based on our conformal registration technique, we devise an automatic registration and interactive registration technique, which can reduce user interventions during template fitting. We demonstrate the versatility of our technique on a wide range of surfaces.
Elective neck dissection during salvage total laryngectomy – a beneficial prognostic effect in locally advanced recurrent tumours
Authors: Hilly O. , Gil Z. , Goldhaber D. , Amit M. , Biadsee A. , Popovtzer A. , Shvero J. , Cohen J. , Fliss D. , Feinmesser R. , Bachar G. 
Published: August 2014

ObjectivesElective neck dissection during salvage laryngectomy is controversial. The goal of our study was to evaluate the effect of elective neck dissection during salvage laryngectomy in patients with locally advanced disease at recurrence.DesignMulticentre, retrospective study.SettingsTwo tertiary medical centres.ParticipantsEighty‐seven patients treated by salvage laryngectomy.Main outcome measuresDisease‐Free and Overall Survival.ResultsFifty‐seven patients underwent salvage total laryngectomy for locally advanced recurrent squamous cell carcinoma of the larynx, and 30 patients underwent salvage laryngectomy for limited recurrent disease. Elective lateral neck dissection was performed in 48 patients. The groups were similar in age, sex, initialTNMstage and pre‐operative treatment. Survival analysis showed that both disease‐free survival and overall survival were improved in patients with locally advanced disease who underwent elective neck dissection. This beneficial effect was not demonstrated in patients with limited disease at recurrence. Multivariate analysis showed that the extent of the recurrent disease as well as elective neck dissection was associated with improved disease‐free survival and overall survival.ConclusionsElective neck dissection during salvage total laryngectomy seems to improve survival in patients with advanced local disease at recurrence. The role of neck dissection in the treatment of smaller tumours awaits further studies.
Clarifying values, risk perceptions, and attitudes to resolve or avoid social conflicts in invasive species management
Authors: Estévez Rodrigo A. , Anderson Christopher B. , Pizarro J. Cristobal , Burgman Mark A. 
Published: August 2014

AbstractDecision makers and researchers recognize the need to effectively confront the social dimensions and conflicts inherent to invasive species research and management. Yet, despite numerous contentious situations that have arisen, no systematic evaluation of the literature has examined the commonalities in the patterns and types of these emergent social issues. Using social and ecological keywords, we reviewed trends in the social dimensions of invasive species research and management and the sources and potential solutions to problems and conflicts that arise around invasive species. We integrated components of cognitive hierarchy theory and risk perceptions theory to provide a conceptual framework to identify, distinguish, and provide understanding of the driving factors underlying disputes associated with invasive species. In the ISI Web of Science database, we found 15,915 peer‐reviewed publications on biological invasions, 124 of which included social dimensions of this phenomenon. Of these 124, 28 studies described specific contentious situations. Social approaches to biological invasions have emerged largely in the last decade and have focused on both environmental social sciences and resource management. Despite being distributed in a range of journals, these 124 articles were concentrated mostly in ecology and conservation‐oriented outlets. We found that conflicts surrounding invasive species arose based largely on differences in value systems and to a lesser extent stakeholder and decision maker's risk perceptions. To confront or avoid such situations, we suggest integrating the plurality of environmental values into invasive species research and management via structured decision making techniques, which enhance effective risk communication that promotes trust and confidence between stakeholders and decision makers.Clarificar los Valores, Percepciones de Riesgo y Actitudes para Resolver o Evitar Conflictos Sociales en el Manejo de Especies Invasoras
Recurrence after perineal rectosigmoidectomy: when and why?
Authors: Kim M. , Reibetanz J. , Schlegel N. , Krajinovic K. , Köstler H. , Germer C.‐T. , Isbert C. 
Published: August 2014

AbstractAimReported recurrence rates after perineal rectosigmoidectomy (Altemeier's procedure) in patients with full‐thickness rectal prolapse vary from 0% to 60%. The object of this study was to analyse risk factors for recurrence after this procedure.MethodFrom May 2004 to December 2012, 63 consecutive patients suffering from full‐thickness rectal prolapse undergoing perineal rectosigmoidectomy were included. Of these 46 were female and the median age of the whole group was 79 (30–90) years. The median follow‐up was 53 (3–99) months. Patient characteristics and operative parameters were compared between patients with and without recurrence.ResultsOne patient died and another patient needed re‐operation. Eight full‐thickness recurrences occurred in eight patients after a median of 18 (6–48) months. Stapled compared with handsewn anastomosis (hazard ratio 7.96, 95% confidence interval 1.90–33.47; P = 0.001) and shorter specimen length (hazard ratio 4.06, 95% confidence interval 0.97–16.99; P = 0.03) increased the risk of recurrence in Cox regression analysis.ConclusionThe operative technique including stapled anastomosis and length of the resected specimen seems to be associated with a high recurrence rate after perineal rectosigmoidectomy.
Comparing species distribution models constructed with different subsets of environmental predictors
Authors: Bucklin David N. , Basille Mathieu , Benscoter Allison M. , Brandt Laura A. , Mazzotti Frank J. , Romañach Stephanie S. , Speroterra Carolina , Watling James I. 
Published: August 2014

AbstractAimTo assess the usefulness of combining climate predictors with additional types of environmental predictors in species distribution models for range‐restricted species, using common correlative species distribution modelling approaches.LocationFlorida, USAMethodsWe used five different algorithms to create distribution models for 14 vertebrate species, using seven different predictor sets: two with bioclimate predictors only, and five ‘combination’ models using bioclimate predictors plus ‘additional’ predictors from groups representing: human influence, land cover, extreme weather or noise (spatially random data).We use a linear mixed‐model approach to analyse the effects of predictor set and algorithm on model accuracy, variable importance scores and spatial predictions.ResultsRegardless of modelling algorithm, no one predictor set produced significantly more accurate models than all others, though models including human influence predictors were the only ones with significantly higher accuracy than climate‐only models. Climate predictors had consistently higher variable importance scores than additional predictors in combination models, though there was variation related to predictor type and algorithm. While spatial predictions varied moderately between predictor sets, discrepancies were significantly greater between modelling algorithms than between predictor sets. Furthermore, there were no differences in the level of agreement between binary ‘presence–absence’ maps and independent species range maps related to the predictor set used.Main conclusionsOur results indicate that additional predictors have relatively minor effects on the accuracy of climate‐based species distribution models and minor to moderate effects on spatial predictions. We suggest that implementing species distribution models with only climate predictors may provide an effective and efficient approach for initial assessments of environmental suitability.
Efficacy and safety of once‐weekly glucagon‐like peptide 1 receptor agonist albiglutide (HARMONY 1 trial): 52‐week primary endpoint results from a randomized, double‐blind, placebo‐controlled trial in patients with type 2 diabetes mellitus not controlled on pioglitazone, with or without metformin
Authors: Reusch J. , Stewart M. W. , Perkins C. M. , Cirkel D. T. , Ye J. , Perry C. R. , Reinhardt R. R. , Bode B. W. 
Published: August 2014

AimsTo show that albiglutide, a glucagon‐like peptide‐1 receptor agonist, is an effective and generally safe treatment to improve glycaemic control in patients with type 2 diabetes mellitus whose hyperglycaemia is inadequately controlled with pioglitazone (with or without metformin).MethodsIn this 3‐year, randomized, double‐blind, placebo‐controlled study, 310 adult patients on a regimen of pioglitazone (with or without metformin) were randomly assigned to receive additional treatment with albiglutide [30 mg subcutaneous (s.c.) once weekly, n = 155] or matching placebo (n = 155). The primary efficacy endpoint was change from baseline to week 52 (intention‐to‐treat) in glycated haemoglobin (HbA1c).ResultsThe model‐adjusted change from baseline in HbA1c at week 52 was significantly better with albiglutide than with placebo (−0.8%, 95% confidence interval −1.0, −0.6; p < 0.0001). Change from baseline fasting plasma glucose was −1.3 mmol/l in the albiglutide group and +0.4 mmol/l in the placebo group (p < 0.0001); a significantly higher percentage of patients reached the HbA1c goals with albiglutide (p < 0.0001), and the rate of hyperglycaemia rescue up to week 52 for albiglutide was 24.4 versus 47.7% for placebo (p < 0.0001). Albiglutide plus pioglitazone had no impact on weight, and severe hypoglycaemia was observed rarely (n = 2). With few exceptions, the results of safety assessments were similar between the groups, and most adverse events (AEs) were mild or moderate. The 52‐week incidence rates for gastrointestinal AEs for albiglutide and placebo were: 31.3 and 29.8%, respectively (diarrhoea: 11.3 and 8.6%; nausea: 10.7 and 11.3%; vomiting: 4.0 and 4.0%).ConclusionsAlbiglutide 30 mg administered once weekly as an add‐on to pioglitazone (with or without metformin) provided effective and durable glucose lowering and was generally well tolerated.
TP53 mutations and MDM2SNP309 identify subgroups of AML patients with impaired outcome
Authors: Falk Ingrid Jakobsen , Willander Kerstin , Chaireti Roza , Lund Johan , Nahi Hareth , Hermanson Monica , Gréen Henrik , Lotfi Kourosh , Söderkvist Peter 
Published: August 2014

AbstractBackgroundTP53 is commonly mutated in several cancers and confers treatment resistance and poor prognosis. Altered expression of mouse double minute 2 (MDM2), a negative regulator of p53, may also attenuate normal p53 signaling, thereby enhancing tumor transformation and resistance to apoptosis. The single nucleotide polymorphism (SNP) 309 has been reported to increase MDM2 expression and impair normal p53 response.Experimental designWe investigated the frequency and impact of TP53 mutations (TP53mut) and MDM2SNP309 on treatment outcome and overall survival (OS) in 189 Swedish acute myeloid leukemia patients. The genetic analyses were performed using SSCA and direct sequencing (for mutations in exon 5–8 of TP53) and Pyrosequencing (for the MDM2SNP309).ResultsWe found a high frequency (22%) of TP53mut in patients with cytogenetic aberrations, with association to high‐risk cytogenetics (P < 0.001). TP53mut patients had lower response rates (22% compared with 76% CR in TP53 wild‐type (wt) patients, P < 0.001) and reduced OS (2 and 16 months, respectively, P < 0.001). In TP53wt patients with high or intermediate risk cytogenetic aberrations, the MDM2SNP309 conferred an impaired outcome, with patients carrying the alternative G‐allele having shorter OS compared with T/T patients (median 9 vs. 50 months, P = 0.020).ConclusionsOur results show that TP53mut analysis and MDM2SNP309 genotyping may be useful tools for prognostication, risk stratification, and selection of patients most likely to benefit from new drugs targeting the p53 signaling pathway.
Improving efficiency of merging symbolic rules into integrated rules: splitting methods and mergability criteria
Authors: Prentzas Jim , Hatzilygeroudis Ioannis 
Published: August 2014

AbstractNeurules are a type of neuro‐symbolic rules integrating neurocomputing and production rules. Each neurule is represented as an adaline unit. Neurules exhibit characteristics such as modularity, naturalness and ability to perform interactive and integrated inferences and provide explanations for reached conclusions. One way of producing a neurule base is through conversion of an existing symbolic rule base yielding an equivalent but more compact rule base. The conversion process merges symbolic rules having the same conclusion into one or more neurules. Because of the inability of the adaline unit to handle inseparability, more than one neurule for each conclusion may be produced by splitting the initial set of symbolic rules into subsets. This paper presents research work improving the conversion process in terms of runtime and number of produced neurules. First, we show how easier it is to construct a neurule base than a connectionist one. Second, we present alternative rule set splitting methods. Finally, we define criteria concerning the ability or inability to convert a rule set into a single, equivalent, but more compact rule. With application of such mergability criteria, the conversion process of symbolic rules into neurules becomes more time‐efficient. All the aforementioned are supported by experimental results.
Variation in pantothenate kinase type determines the pantothenamide mode of action and impacts on coenzyme A salvage biosynthesis
Authors: de Villiers Marianne , Barnard Leanne , Koekemoer Lizbé , Snoep Jacky L. , Strauss Erick 
Published: August 2014

N‐substituted pantothenamides are analogues of pantothenic acid, the vitamin precursor of CoA, and constitute a class of well‐studied bacterial growth inhibitors that show potential as new antibacterial agents. Previous studies have highlighted the importance of pantothenate kinase (PanK; EC 2.7.1.33) (the first enzyme of CoA biosynthesis) in mediating pantothenamide‐induced growth inhibition by one of two proposed mechanisms: first, by acting on the pantothenamides as alternate substrates (allowing their conversion into CoA antimetabolites, with subsequent effects on CoA‐ and acyl carrier protein‐dependent processes) or, second, by being directly inhibited by them (causing a reduction in CoA biosynthesis). In the present study we used structurally modified pantothenamides to probe whether PanKs interact with these compounds in the same manner. We show that the three distinct types of eubacterial PanKs that are known to exist (PanKI, PanKII and PanKIII) respond very differently and, consequently, are responsible for determining the pantothenamide mode of action in each case: although the promiscuous PanKI enzymes accept them as substrates, the highly selective PanKIIIs are resistant to their inhibitory effects. Most unexpectedly, Staphylococcus aureus PanK (the only known example of a bacterial PanKII) experiences uncompetitive inhibition in a manner that is described for the first time. In addition, we show that pantetheine, a CoA degradation product that closely resembles the pantothenamides, causes the same effect. This suggests that, in S. aureus, pantothenamides may act by usurping a previously unknown role of pantetheine in the regulation of CoA biosynthesis, and validates its PanK as a target for the development of new antistaphylococcal agents.