bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stem cell‐based therapy for Huntington's disease
Authors: Maucksch Christof , Vazey Elena M. , Gordon Renee J. , Connor Bronwen 
Published: October 2012

AbstractHuntington's disease (HD) is a late‐onset neurodegenerative disease characterized by a progressive loss of medium spiny neurons in the basal ganglia. The development of stem cell‐based therapies for HD aims to replace lost neurons and/or to prevent cell death. This review will discuss pre‐clinical studies which have utilized stem or progenitor cells for transplantation therapy using HD animal models. In several studies, neural stem and progenitor cells used as allotransplants and xenografts have been shown to be capable of surviving transplantation and differentiating into mature GABAergic neurons, resulting in behavioral improvements. Beneficial effects have also been reported for transplantation of stem cells derived from non‐neural tissue, for example, mesenchymal‐ and adipose‐derived stem cells, which have mainly been attributed to their secretion of growth and neurotrophic factors. Finally, we review studies using stem cells genetically engineered to over‐express defined neurotrophic factors. While these studies prove the potential of stem cells for transplantation therapy in HD, it also becomes clear that technical and ethical issues regarding the availability of stem cells must be solved before human trials can be conducted. J. Cell. Biochem. 114: 754–763, 2013. © 2012 Wiley Periodicals, Inc.
Association between human parainfluenza virus type 1 and smoking history in patients with an abdominal aortic aneurysm
Authors: Garrafa Emirena , Marengoni Alessandra , Nave Rosalba della , Caimi Luigi , Cervi Edoardo , Giulini Stefano Maria , Imberti Luisa , Bonardelli Stefano 
Published: October 2012

AbstractSeveral studies have suggested that infectious agents may induce the development of abdominal aortic aneurysms and/or accelerate their progression. The aim of this study was to evaluate the presence of the respiratory‐transmitted viruses such as influenza A and B and parainfluenza type 1 genomes in bioptic fragments of abdominal aortic aneurysms. Furthermore, the association between viral infection and traditional risk factors for aneurysms was investigated employing multivariate logistic regression models. The genome of parainfluenza 1 was detected in 11 out of 57 patients with abdominal aortic aneurysm, influenza A only in one, whereas none of the specimens analyzed resulted positive for influenza B. After adjustment of age, gender, and clinical diagnosis, being current smokers was associated independently with parainfluenza 1 detection in aneurysms. The identification of parainfluenza 1 in aortic aneurysm biopsies supports previous observations of a possible role of viruses in the lesion development. Smoking, by interfering with the respiratory tract's ability to defend itself and predisposing to upper and lower respiratory tract infections may accelerate the onset and progression of abdominal aortic aneurysms. J. Med. Virol. 85:99–104, 2012. © 2012 Wiley Periodicals, Inc.
Hepatitis C virus NS2 protease inhibits host cell antiviral response by inhibiting IKKε and TBK1 functions
Authors: Kaukinen Pasi , Sillanpää Maarit , Nousiainen Laura , Melén Krister , Julkunen Ilkka 
Published: October 2012

AbstractHepatitis C virus (HCV) encodes for several proteins that can interfere with host cell signaling and antiviral response. Previously, serine protease NS3/4A was shown to block host cell interferon (IFN) production by proteolytic cleavage of MAVS and TRIF, the adaptor molecules of the RIG‐I and TLR3 signaling pathways, respectively. This study shows that another HCV protease, NS2 can interfere efficiently with cytokine gene expression. NS2 and its proteolytically inactive mutant forms were able to inhibit type I and type III IFN, CCL5 and CXCL10 gene promoters activated by Sendai virus infection. However, the CXCL8 gene promoter was not inhibited by NS2. In addition, constitutively active RIG‐I (ΔRIG‐I), MAVS, TRIF, IKKε, and TBK1‐induced activation of IFN‐β promoter was inhibited by NS2. Cotransfection experiments with IKKε or TBK1 together with interferon regulatory factor 3 (IRF3) and HCV expression constructs revealed that NS2 in a dose‐dependent manner inhibited IKKε and especially TBK1‐induced IRF3 phosphorylation. GST pull‐down experiments with GST‐NS2 and in vitro‐translated and cell‐expressed IKKε and TBK1 demonstrated direct physical interactions of the kinases with NS2. Further evidence that the IKKε/TBK1 kinase complex is the target for NS2 was obtained from the observation that the constitutively active form of IRF3 (IRF3‐5D) activated readily IFN‐β promoter in the presence of NS2. The present study identified HCV NS2 as a potent interferon antagonist, and describes an explanation of how NS2 downregulates the major signaling pathways involved in the development of host innate antiviral responses. J. Med. Virol. 85:71–82, 2012. © 2012 Wiley Periodicals, Inc.
Dystrophin and utrophin “double knockout” dystrophic mice exhibit a spectrum of degenerative musculoskeletal abnormalities
Authors: Isaac Christian , Wright Adam , Usas Arvydas , Li Hongshuai , Tang Ying , Mu Xiaodong , Greco Nicholas , Dong Qing , Vo Nam , Kang James , Wang Bing , Huard Johnny 
Published: October 2012

AbstractDuchenne muscular dystrophy (DMD) is a degenerative muscle disorder characterized by the lack of dystrophin expression at the sarcolemma of muscle fibers. In addition, DMD patients acquire osteopenia, fragility fractures, and scoliosis indicating that a deficiency in skeletal homeostasis coexists but little is known about the effects of DMD on bone and other connective tissues within the musculoskeletal system. Recent evidence has emerged implicating adult stem cell dysfunction in DMD myopathogenesis. Given the common mesenchymal origin of muscle and bone, we sought to investigate bone and other musculoskeletal tissues in a DMD mouse model. Here, we report that dystrophin–utrophin double knockout (dko) mice exhibit a spectrum of degenerative changes, outside skeletal muscle, in bone, articular cartilage, and intervertebral discs, in addition to reduced lifespan, muscle degeneration, spinal deformity, and cardiomyopathy previously reported. We also report these mice to have a reduced capacity for bone healing and exhibit spontaneous heterotopic ossification in the hind limb muscles. Therefore, we propose the dko mouse as a model for premature musculoskeletal aging and posit that a similar phenomenon may occur in patients with DMD. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 343–349, 2013
A finite element‐based level set method for fluid–elastic solid interaction with surface tension
Authors: Pino Muñoz D. , Bruchon J. , Drapier S. , Valdivieso F. 
Published: October 2012

SUMMARYA numerical method for simulating fluid–elastic solid interaction with surface tension is presented. A level set method is used to capture the interface between the solid bodies and the incompressible surrounding fluid, within an Eulerian approach. The mixed velocity–pressure variational formulation is established for the global coupled mechanical problem and discretized using a continuous linear approximation in both velocity and pressure. Three ways are investigated to reduce the spurious oscillations of the pressure that appear at the fluid–solid interface. First, two stabilized finite element methods are used: the MINI‐element and the algebraic subgrid method. Second, the surface integral corresponding to the surface tension term is treated either by the continuum surface force technique or by a surface local reconstruction algorithm. Finally, besides the direct evaluation method proposed by Bruchon et al., an alternative method is proposed to avoid the explicit computation of the surface curvature, which may be a source of difficulty. These different issues are addressed through various numerical examples, such as the two incompressible fluid flow, the elastic inclusion embedded into a Newtonian fluid, or the study of a granular packing. Copyright © 2012 John Wiley & Sons, Ltd.
Enrichment based multiscale modeling for thermo‐stress analysis of heterogeneous material
Authors: Macri Michael , Littlefield Andrew 
Published: October 2012

SUMMARYThis paper details a novel new multiscale technique for modeling heterogeneous materials undergoing substantial thermal stresses. The technique is based on an enriched partition of unity approach that incorporates the thermal effects occurring on the microstructure into the global model. We demonstrate the effectiveness of this technique by implementing it into both the standard finite element method and the octree partition of unity method (OctPUM). The results demonstrate that the technique has uniquely improved accuracy over the homogenization method conditional to the method into which it is implemented in. The multiscale technique, when implemented into either the standard finite element method or OctPUM, increases the accuracy of the strain energy calculation. When the multiscale technique is implemented into OctPUM, it also is able to capture the unique stress fields on the microstructure of the model. Published 2012. This article is a US Government work and is in the public domain in the USA.
An adaptive time integration strategy based on displacement history curvature
Authors: Lages E.N. , Silveira E.S.S. , Cintra D.T. , Frery A.C. 
Published: October 2012

SUMMARYThis work introduces a time‐adaptive strategy that uses a refinement estimator on the basis of the first Frenet curvature. In dynamics, a time‐adaptive strategy is a mechanism that interactively proposes changes to the time step used in iterative methods of solution. These changes aim to improve the relation between quality of response and computational cost. The method here proposed is suitable for a variety of numerical time integration problems, for example, in the study of bodies subjected to dynamical loads. The motion equation in its space‐discrete form is used as reference to derive the formulation presented in this paper. Our method is contrasted with other ones based on local error estimator and apparent frequencies. We check the performance of our proposal when employed with the central difference, the explicit generalized‐ α and the Chung‐Lee integration methods. The proposed refinement estimator demands low computational resources, being easily applied to several direct integration methods. Copyright © 2012 John Wiley & Sons, Ltd.
Interaction of polypeptide antibiotic gramicidin S with platelets
Authors: Hackl Ellen V. , Berest Vladimir P. , Gatash Sergey V. 
Published: October 2012

Gramicidin S (GS) is a cyclic decapeptide antibiotic active against both Gram‐positive and Gram‐negative bacteria as well as against several pathogenic fungi. However, clinical application of GS is limited because of GS hemolytic activity. The large number of GS analogues with potentially attenuated hemolytic activity has been developed over the last two decades. For all new GS derivatives, the antimicrobial test is accompanied with the hemolytic activity assay. At the same time, neither GS nor its analogues were tested against other blood cells. In the present work, the effects of GS on platelets and platelet aggregates have been studied.GS interaction with platelets is concentration dependent and leads either to platelet swelling or platelet shape change. Effect of GS on platelets is independent of platelet aggregation mechanism.GS induces disaggregation of platelet aggregates formed in the presence of aggregation agonists. The rate of the GS interaction with platelet membranes depends on membrane lipid mobility and significantly increases with temperature. The interaction of GS with the platelet membranes depends strongly on the state of the membrane lipids. Factors affecting the membrane lipids (temperature, lipid peroxidation and ionising irradiation) modify GS interaction with platelets.Our results show that GS is active not only against erythrocytes but also against other blood cells (platelets). The estimated numbers of GS molecules per 1 µm2 of a blood cell required to induce erythrocyte hemolysis and disaggregation of platelet aggregates are comparable. This must be considered when developing new antimicrobial GS analogues with improved hemolytic properties. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.
Spin arrangements of the first family line groups
Authors: Lazić Nataša , Milivojević Marko , Damnjanović Milan 
Published: October 2012

AbstractMagnetic properties of materials are, partly or in some cases completely, determined by the ground state spin arrangements. Their symmetry is, in some cases based on the magnetic groups, but this approach is incapable to include many classes of helimagnets, and a generalization of spin space groups was introduced. On the other hand, geometrical symmetries of regular quasi one‐dimensional systems, including various types of nanotubes, nanowires, or polymers, are gathered into line groups. Concerning magnetic order, it turns out that the atoms carrying spins in helimagnets usually single out quasi one‐dimensional substructure. Therefore spin line groups are necessary tool in description and classification, as well as deep understanding of properties of wide class of helimagnets. Here we derive spin groups associated to the first family line groups, and compare spin arrangements compatible with these and the corresponding magnetic groups. Presented theory is illustrated by several examples of quasi one‐dimensional helimagnets: cuprates, hexaferrites, etc.
Governing Innovation for Sustainable Development in the Danish Biogas Sector – a Historical Overview and Analysis of Innovation
Authors: Lybæk Rikke , Christensen Thomas Budde , Kjær Tyge 
Published: October 2012

ABSTRACTDrawing on innovation literature, this article contests the wisdom of the conventional linear innovation model (invention–demonstration–commercialization–diffusion) and argues that innovation in the case of biogas is, instead, characterized by numerous feedback loops between research, demonstration, commercialization and diffusion. Furthermore, these feedback loops are heavily influenced and shaped by public sector interventions in many aspects of the innovation activities. The article presents the history of Danish farm biogas plants and their present status and discusses the development and implementation of the technology in relation to innovation achievements. The article thus concludes that innovation can be better understood in terms of a dynamic model drawing on initiatives by private, public and academic actors. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment
Continuous KAOS, ASM, and formal control system design across the continuous/discrete modeling interface: a simple train stopping application
Authors: Banach Richard , Zhu Huibiao , Su Wen , Huang Runlei 
Published: October 2012

Abstract
A very simple model for train stopping is used as a vehicle for investigating how the development of a control system, initially designed in the continuous domain and subsequently discretized, can be captured within a formal development process compatible with standard model based refinement methodologies. Starting with a formalized requirements analysis using KAOS, an abstract model of the continuous system is created in the ASM formalism. This requires extensions of the KAOS and ASM formalisms, capable of dealing with quantities evolving continuously over real time, which are developed. After considering how the continuous system, described as a continuous control system in the state space framework, can be discretized, a discrete control system is created in the state space framework. This is re-expressed in the ASM formalism. The rigorous results on the relationship between continuous and discrete control system models that are needed to establish provable properties of the discretization, then become the ingredients of a retrenchment between continuous and discrete ASM models, and are thus fully integrated into the formal development. The discrete ASM model can then be further refined towards implementation.
Scaling up: how do exogenous fluctuations in individual‐based resource competition models re‐emerge in aggregated stochastic population models?
Authors: Johst Karin , Lima Mauricio , Berryman Alan A. 
Published: October 2012

AbstractIn applied population dynamics the choice of stochastic per capita growth function has implications for population viability analyses, management recommendations, and pest control. This model choice is often based on statistical criteria, mathematical tractability or personal preferences, and general ecological guidelines are either too vague or entirely missing. To identify such guidelines, it is important to understand how exogenous and endogenous factors interact at the individual level and re‐emerge at the aggregated population level. We therefore study different types of resource competition (contest vs. scramble competition) and different types of exogenous fluctuations (food and weather fluctuations) at the individual level in a simple individual‐based simulation model. We statistically fit the resulting time series to find out (1) which functional form of the growth function (‘hyperbolic’ or ‘exponential’) better describes contest and scramble competition and (2) whether the pattern of population fluctuations resulting from the simulations can be assigned to vertical, lateral or nonlinear perturbations in the stochastic growth function (a classification scheme suggested by Royama 1992, Analytical Population Dynamics, Chapman and Hall, London). We found that the same type of competition can result in ‘hyperbolic’ or ‘exponential’ functional forms, depending on the type of exogenous fluctuations. So it is the interplay between exogenous variability and endogenous resource competition that affects model performance. In contrast to the widespread assumption of vertical (additive) perturbations, our findings highlight the importance of (non‐additive) lateral and nonlinear perturbations and their combinations with vertical perturbations. The choice of the stochastic growth function should therefore consider not only statistical criteria but also ecological guidelines. We derive such ecological guidelines from our analysis.
Determinant factors influencing the spatial distributions of subtropical lianas are correlated with components of functional trait spectra
Authors: Kusumoto Buntarou , Enoki Tsutomu , Kubota Yasuhiro 
Published: October 2012

AbstractLianas are important vegetation components that control structure and function, especially in tropical and subtropical forests. To explore the spatial assembly mechanisms of a subtropical liana community, we tested the following hypotheses: spatial distributions of subtropical lianas are determined by forest structures and topographic features, which are surrogates for host/light availability and edaphic/water conditions, respectively, and these effects are mediated through species functional traits. We examined the spatial distribution of lianas in two plots (areas 9 and 16 ha) representing landscapes in an intact forest and a secondary forest, and analyzed spatial distribution pattern at the species level using a simple, spatially explicit model. We also examined the correlations between determinant factors for species distribution and species functional traits, including climbing habits, leaf traits and wood density. The spatial distribution of lianas was controlled mainly by topographic gradient. Most species had preferences for concave topographies, i.e., valley habitats. Any covariates related to the host (or to light) had little influence on the distribution of most liana species. Distributional responses to topography were different among species, and associated significantly with leaf nitrogen content and climbing habit, but not with wood density. The correlation between variation in habitat preferences and leaf economic spectrum suggests that an environmental filter for physiological response to topography is the important mechanism shaping the spatial patterns of this subtropical liana community.
Neuropsychiatric Symptoms and the Use of Complementary and Alternative Medicine
Authors: Purohit Maulik P. , Wells Rebecca Erwin , Zafonte Ross D. , Davis Roger B. , Phillips Russell S. 
Published: October 2012

ObjectivesTo assess the prevalence of complementary and alternative medicine (CAM) use by U.S. adults reporting neuropsychiatric symptoms and whether this prevalence changes based on the number of symptoms reported. Additional objectives include identifying patterns of CAM use, reasons for use, and disclosure of use with conventional providers in U.S. adults with neuropsychiatric symptoms.DesignSecondary database analysis of a prospective survey.ParticipantsA total of 23,393 U.S. adults from the 2007 National Health Interview Survey.MethodsWe compared CAM use between adults with and without neuropsychiatric symptoms. Symptoms included self‐reported anxiety, depression, insomnia, headaches, memory deficits, attention deficits, and excessive sleepiness. CAM use was defined as use of mind−body therapies (eg, meditation), biological therapies (eg, herbs), or manipulation therapies (eg, massage) or alternative medical systems (eg, Ayurveda). Statistical analysis included bivariable comparisons and multivariable logistical regression analyses.Main Outcome MeasuresThe prevalence of CAM use among adults with neuropsychiatric symptoms within the previous 12 months and the comparison of CAM use between those with and without neuropsychiatric symptoms.ResultsAdults with neuropsychiatric symptoms had a greater prevalence of CAM use compared with adults who did not have neuropsychiatric symptoms (43.8% versus 29.7%, P < .001); this prevalence increased with an increasing number of symptoms (trend, P < .001). Differences in the likelihood of CAM use as determined by the number of symptoms persisted after we adjusted for covariates. Twenty percent of patients used CAM because standard treatments were either too expensive or ineffective, and 25% used CAM because it was recommended by a conventional provider. Adults with at least one neuropsychiatric symptom were more likely to disclose the use of CAM to a conventional provider (47.9% versus 39.0%, P < .001).ConclusionMore than 40% of adults with neuropsychiatric symptoms commonly observed in many diagnoses use CAM; an increasing number of symptoms was associated with an increased likelihood of CAM use.
The reversal of agricultural reform in Uganda: Ownership and values
Authors: Kjær Anne Mette , Joughin James 
Published: October 2012

AbstractThis article explores the nature of ownership in a reform of the multi-donor-funded agricultural advisory service in Uganda. We argue that although there was a long process of programme formulation in which all stakeholders were heard, ownership was not as encompassing as it first appeared. In essence, the agricultural reform programme represented market-oriented values that were not echoed in large parts of the Ugandan polity. The eventual reversal of policy, back to government-provided extension, and to a large programme of heavily subsidised input supply, testifies to that. In addition, key stakeholders, notably local politicians and officials in the Ministry of Agriculture, Animal Industry, and Fisheries (MAAIF), were shut out from the original programme and this threatened its viability. If a genuine analysis of the economic and political context had been carried out, the donors might have anticipated this. Instead, they were revealed as ill-equipped to counteract the politicisation and re-claiming of ownership by the Ugandan government.