bluuebunny/crossref_metadata_2025_split huggingface dataset:
The nucleocytoplasmic conflict, a driving force for the emergence of plant organellar RNA editing
Authors: Castandet Benoît , Araya Alejandro 
Published: December 2011

AbstractRNA editing challenges the central dogma of molecular biology by changing the genetic information at the transcript level. In plant organelles, RNAs are modified by deamination of some specific cytosine residues, but the origin of this process remains puzzling. Different from the generally accepted neutral model to explain the emergence of RNA editing in plant organelles, we propose a new hypothesis based on the nucleocytoplasmic conflict theory. We assume that mutations in organellar genomes arose first and spread into the population provided they increased the transmission of their own maternally inherited genome. RNA editing appeared subsequently as a nuclear‐encoded correction mechanism to restore the transmission of the nuclear genome. In plants, a well‐known consequence of the nucleocytoplasmic conflict is cytoplasmic male sterility (CMS) which is counteracted by the emergence of fertility restorer genes (Rf) belonging to the pentatricopeptide repeat (PPR) protein family. Interestingly, RNA‐editing deficiency can lead to CMS, and it now clearly appears that PPR proteins are major players in RNA editing. This striking similarity between the mechanisms of fertility restoration and RNA editing can be explained if both reactions are the consequence of the same driving force, the nucleocytoplasmic conflict. Similarly, the prevalence of RNA editing in eukaryotic organellar genomes could also be a consequence of the genetic antagonism between organellar and nuclear genomes. © 2011 IUBMB Life, 2011
Characterization of hexacationic imidazolium ionic liquids as effective and highly stable gas chromatography stationary phases
Authors: González‐Álvarez Jaime , Blanco‐Gomis Domingo , Arias‐Abrodo Pilar , Díaz‐Llorente Daniel , Ríos‐Lombardía Nicolás , Busto Eduardo , Gotor‐Fernández Vicente , Gutiérrez‐Álvarez María D. 
Published: December 2011

AbstractPolycationic ionic liquids (ILs) are an attractive class of ILs with great potential applicability as gas chromatography stationary phases. A family of hexacationic imidazolium ILs derived from the cycloalkanol family was chemically first prepared in a straightforward manner and then applied for analytical separation purposes. Four tuneable engineering vectors, namely cation ring size structure, anion nature, spatial disposition of cycloalkanol substituents and O‐substitution, were considered as experimental parameters for the design of the desired ionic liquids. A total number of five new phases based on a common benzene core respectively exhibited column efficiencies around to 2500 plates/m, broad operating temperature ranges and also, even more importantly, good thermal stabilities (bleeding temperature between 260 and 365°C), finding variations in the selectivity and analytes elution orders depending on the IL structures. Their solvation characteristics were evaluated using the Abraham solvation parameter model, establishing clear correlations between their cation structure and retention capability with respect to certain analytes. The study of relationships between the ILs structure and solvation parameters gives us an idea of the IL stationary phase to be used for specific separations.
On Σ11 equivalence relations over the natural numbers
Authors: Fokina Ekaterina B. , Friedman Sy‐David 
Published: December 2011

AbstractWe study the structure of Σ11 equivalence relations on hyperarithmetical subsets of ω under reducibilities given by hyperarithmetical or computable functions, called h‐reducibility and FF‐reducibility, respectively. We show that the structure is rich even when one fixes the number of properly \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Sigma ^1_1\ \big ($\end{document}i.e., Σ11 but not \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\Delta ^1_1\big )$\end{document} equivalence classes. We also show the existence of incomparable Σ11 equivalence relations that are complete as subsets of ω × ω with respect to the corresponding reducibility on sets. We study complete Σ11 equivalence relations (under both reducibilities) and show that existence of infinitely many properly Σ11 equivalence classes that are complete as Σ11 sets (under the corresponding reducibility on sets) is necessary but not sufficient for a relation to be complete in the context of Σ11 equivalence relations.
Stereotypies: A critical appraisal and suggestion of a clinically useful definition
Authors: Edwards Mark J. , Lang Anthony E. , Bhatia Kailash P. 
Published: December 2011

AbstractThe foundations of the clinical classification of movement disorders rest on the precise definition of the words used to describe the disorders. Here we argue that the current use of the term stereotypy falls well short of the precision needed for either clinical or academic use, and fails both to provide a clinically useful diagnostic category and to define a set of conditions that are linked pathophysiologically. The difficulty in defining this concept is not a new one as our review of the history of the term demonstrates. We synthesise this historical background, explore why clinicians have felt it necessary to use the category of stereotypy for certain movements rather than the related category of tics, discuss the multiple uses of the term in current research and clinical practice and on this basis suggest a new definition and classification. © 2011 Movement Disorder Society
Placebo effect characteristics observed in a single, international, longitudinal study in Huntington's disease
Authors: Cubo Esther , González Miguel , del Puerto Inés , de Yébenes Justo Garcia , Arconada Olga Fernández , Gabriel y Galán José María Trejo ,   on behalf of the European Huntington's Disease Initiative Study Group
Published: December 2011

AbstractBackground:Classically, clinical trials are based on the placebo‐control design. Our aim was to analyze the placebo effect in Huntington's disease.Methods:Placebo data were obtained from an international, longitudinal, placebo‐controlled trial for Huntington's disease (European Huntington's Disease Initiative Study Group). One‐hundred and eighty patients were evaluated using the Unified Huntington Disease Rating Scale over 36 months. A placebo effect was defined as an improvement of at least 50% over baseline scores in the Unified Huntington Disease Rating Scale, and clinically relevant when at least 10% of the population met it.Results:Only behavior showed a significant placebo effect, and the proportion of the patients with placebo effect ranged from 16% (first visit) to 41% (last visit). Nondepressed patients with better functional status were most likely to be placebo‐responders over time.Conclusions:In Huntington's disease, behavior seems to be more vulnerable to placebo than overall motor function, cognition, and function © 2011 Movement Disorder Society
β‐Carotene and lycopene affect endothelial response to TNF‐α reducing nitro‐oxidative stress and interaction with monocytes
Authors: Di Tomo Pamela , Canali Raffaella , Ciavardelli Domenico , Di Silvestre Sara , De Marco Alessandro , Giardinelli Annalisa , Pipino Caterina , Di Pietro Natalia , Virgili Fabio , Pandolfi Assunta 
Published: December 2011

ScopeCardiovascular disease (CVD) is associated with vascular oxidative imbalance and inflammation. Increased reactive oxygen species (ROS) generation is associated with a functional inactivation of nitric oxide (NO) due to the reaction with O−2, leading to peroxynitrite (ONOO−) formation and subsequent reduction in the beneficial effect of vascular NO bioavailability. Carotenoids'‐rich diets have been associated with decreased risk of CVD, but the underlying mechanism is still unknown.Methods and resultsIn human umbilical vein endothelial cells (HUVECs), both β‐carotene (BC) or lycopene (Lyc) significantly affected tumor necrosis factor‐α (TNF‐α)‐induced inflammation, being associated with a significant decrease in the generation of ROS (spectrofluorometry) and nitrotyrosine (an index of ONOO− formation, cytofluorimetry), an increased NO/cGMP (cyclic guanosine monophosphate) levels (EIA), and a down‐regulation of NF‐κB‐dependent adhesion molecule expression (Western blot and EMSA) and monocyte–HUVEC interaction (adhesion assay). Our results indicate that BC or Lyc treatment reduce the inflammatory response in TNF‐α‐treated HUVECs. This is due to the redox balance protection and to the maintenance of NO bioavailability.ConclusionOur observations provide background for a novel mechanism for carotenoids' anti‐inflammatory activity in the vasculature and may contribute to a better understanding of the protective effects of carotenoid‐rich diets against CVD risk.
Metabolomics for measuring phytochemicals, and assessing human and animal responses to phytochemicals, in food science
Authors: McGhie Tony K. , Rowan Daryl D. 
Published: December 2011

AbstractMetabolomics, comprehensive metabolite analysis, is finding increasing application as a tool to measure and enable the manipulation of the phytochemical content of foods, to identify the measures of dietary intake, and to understand human and animal responses to phytochemicals in the diet. Recent applications of metabolomics directed toward understanding the role of phytochemicals in food and nutrition are reviewed.
k‐t sparse GROWL: Sequential combination of partially parallel imaging and compressed sensing in k‐t space using flexible virtual coil
Authors: Huang Feng , Lin Wei , Duensing George R. , Reykowski Arne 
Published: December 2011

AbstractBecause dynamic MR images are often sparse in x‐f domain, k‐t space compressed sensing (k‐t CS) has been proposed for highly accelerated dynamic MRI. When a multichannel coil is used for acquisition, the combination of partially parallel imaging and k‐t CS can improve the accuracy of reconstruction. In this work, an efficient combination method is presented, which is called k‐t sparse Generalized GRAPPA fOr Wider readout Line. One fundamental aspect of this work is to apply partially parallel imaging and k‐t CS sequentially. A partially parallel imaging technique using a Generalized GRAPPA fOr Wider readout Line operator is adopted before k‐t CS reconstruction to decrease the reduction factor in a computationally efficient way while preserving temporal resolution. Channel combination and relative sensitivity maps are used in the flexible virtual coil scheme to alleviate the k‐t CS computational load with increasing number of channels. Using k‐t FOCUSS as a specific example of k‐t CS, the experiments with Cartesian and radial data sets demonstrate that k‐t sparse Generalized GRAPPA fOr Wider readout Line can produce results with two times lower root‐mean‐square error than conventional channel‐by‐channel k‐t CS while consuming up to seven times less computational cost. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Simultaneous measurement of cerebral blood flow and transit time with turbo dynamic arterial spin labeling (Turbo‐DASL): Application to functional studies
Authors: Meng Yuguang , Wang Ping , Kim Seong‐Gi 
Published: December 2011

AbstractA turbo dynamic arterial spin labeling method (Turbo‐DASL) was developed to simultaneously measure cerebral blood flow (CBF) and blood transit time with high temporal resolution. With Turbo‐DASL, images were repeatedly acquired with a spiral readout after small‐angle excitations during pseudocontinuous arterial spin labeling and control periods. Turbo‐DASL experiments at 9.4 T without and with diffusion gradients were performed on rats anesthetized with isoflurane or α‐chloralose. We determined blood transit times from carotid arteries to cortical arterial vessels (TTa) from data obtained without diffusion gradients and to capillaries (TTc) from data obtained with diffusion gradients. Cerebral arterial blood volume (CBVa) was also calculated. At the baseline condition, both CBF and CBVa in the somatosensory cortical area were 40–50% less in rats with α‐chloralose than in rats with isoflurane, while TTa and TTc were similar for both anesthetics. Absolute CBF and CBVa were positively correlated, while CBF and TTc were slightly negatively correlated. During forepaw stimulation, CBF increase was 15 ± 3% (n = 7) vs. 60 ± 7% (n = 5), and CBVa increase was 19 ± 9% vs. 46 ± 17% under isoflurane vs. α‐chloralose anesthesia, respectively; CBF vs. CBVa changes were highly correlated. However, TTa and TTc were not significantly changed during stimulation. Our results support that arterial CBV increase plays a major role in functional CBF changes. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
The assessment of the quality of the graft in an animal model for lung transplantation using the metabolomics 1H high‐resolution magic angle spinning NMR spectroscopy
Authors: Benahmed Malika A. , Santelmo Nicola , Elbayed Karim , Frossard Nelly , Noll Eric , Canuet Mathieu , Pottecher Julien , Diemunsch Pierre , Piotto Martial , Massard Gilbert , Namer Izzie J. 
Published: December 2011

AbstractStandards are needed to control the quality of the lungs from nonheart‐beating donors as potential grafts. This was here assessed using the metabolomics 1H high‐resolution magic angle spinning NMR spectroscopy. Selective perfusion of the porcine bilung block was set up 30 min after cardiac arrest with cold Perfadex®. Lung alterations were analyzed at 3, 6, and 8 h of cold ischemia as compared to baseline and to nonperfused lung. Metabolomics analysis of lung biopsies allowed identification of 35 metabolites. Levels of the majority of the metabolites increased over time at 4°C without perfusion, indicating cellular degradation, whereas levels of glutathione decreased. When lung was perfused at 4°C, levels of the majority of the metabolites remained stable, including levels of glutathione. Levels of uracil by contrast showed a reverse profile, as its signal increased over time in the absence of perfusion while being totally absent in perfused samples. Our results showed glutathione and uracil as potential biomarkers for the quality of the lung. The metabolomics 1H high‐resolution magic angle spinning NMR spectroscopy can be efficiently applied for the assessment of the quality of the lung as an original technique characterized by a rapid assessment of intact biopsy samples without extraction and can be implemented in hospital environment. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Mixed FEM of higher‐order for a frictional contact problem
Authors: Schröder Andreas 
Published: December 2011

AbstractThis paper presents mixed finite element methods of higher‐order for an idealized frictional contact problem in linear elasticity. The approach relies on a saddle point formulation where the frictional contact condition is captured by a Lagrange multiplier. The convergence of the mixed scheme is proven and some a priori estimates for the h‐ and p‐method are derived. Furthermore, a posteriori error estimates are presented which rely on the estimation of the discretization error of an auxiliary problem and some further terms capturing the error in the friction and complementary conditions. Numerical results confirm the applicability of the a posteriori error estimates within h‐ and hp‐adaptive schemes. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Radial spreading and stability of a thin rotating liquid droplet
Authors: Boettcher Konrad , Holbach Alexander , Ehrhard Peter 
Published: December 2011

AbstractThin‐film flows are involved in many coating processes, where it is desirable to achieve thin and homogeneous fluid layers. In the present investigations, we treat droplets, spreading on rotating solid substrates. Micro‐scale effects appear, firstly, at the wetting front, where the film height tends to zero. Secondly, micro‐scale effects may appear at other locations, where the free liquid/gas‐interface approaches the solid substrate, as e.g. at film rupture. For such situations, molecular effects need to be considered, e.g. in form of the disjoining pressure (DJP), to get physically‐correct solutions. Otherwise, the spreading can be modeled within the frame of continuum mechanics, augmented by the (empirical) law of Tanner to capture the contact‐line dynamics.We present, on the one hand, an overview of several interesting issues, as (i) spreading with and without considering the DJP, (ii) spreading after central rupture, including hysteresis effects, and (iii) non‐isothermal spreading, including temperature‐dependent surface tension (Marangoni effect) and temperature‐dependent density (Rayleigh‐Bénard effect). On the other hand, we present results for the instability of the contact line, for which the contact line gets corrugated (under isothermal conditions). This instability goes along with a transition from (rotationally‐symmetric) two‐dimensional to three‐dimensional behavior. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Using Multibody Systems for the Investigation of Dynamic Aberrations in High Precision Optics
Authors: Eberhard Peter , Wengert Nicolai 
Published: December 2011

AbstractThe coupling of multibody system dynamics and optical simulations by using ray tracing through moving lens systems will be summarized for both rigid and flexible lens systems. Furthermore, a method will be introduced for efficient simulations in the time domain. This method provides a direct integration of the optical simulation into the equations of motion of a multibody system. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dynamical analysis of the rotor system
Authors: Rendlova Zdenka 
Published: December 2011

AbstractThis paper aims at creating a mathematical model of a bending oscillation rotor system which enables to execute a dynamical analysis of its vibration including the influence of nonlinear bearing characteristics. More specifically, using the finite element method the model of rotating system supported by four hydrodynamic bearings was created. The basic dynamical analysis of the rotor system was performed and the eigenvalues, eigenvectors and stability conditions were evaluated. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibration action on the human body into a tramway in traveling
Authors: Jurco Simona , Arghir Mariana 
Published: December 2011

AbstractThis article presents the vibration action on the human body found in a tram travel, where made the vibration measurements. Also presented a mathematical model with two degrees of freedom. Finally a comparison was made between the results obtained from measurements and the results of integration. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Responses Study of the Seated Human Body Exposed to Vertical Vibration in Various Automotive Postures
Authors: Rodean Simona , Arghir Mariana , Rodean Claudiu Paul , Rodean Cristian George 
Published: December 2011

AbstractIn a seated posture into an autovehicle, humans are most sensitive to whole‐body vibrations under low‐frequency excitation. This research is focused only on the effect of the backrest angle on the biodynamic response functions. In this paper there are present the results of investigations for 10 participants, whose mean body mass was 61.4 kg. For the biodynamic responses of a seated human body subjected to vertical vibrations, three automotive postures was study: without backrest support, with backrest inclined 7° and respectively 15°, by measurement of transmitted vibration in two different situations: with belt and respectively without this. Knowledge of human responses to vibration provides information about the position of backrest support to mitigate vibration transmitted through the body ensuring the health, comfort and performance. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibration by shocks of the human bodies in the working spaces
Authors: Saramet S. Camelia , Arghir Mariana 
Published: December 2011

AbstractThe paper contains the transmitted vibrations produce by shocks to the human bodies into the working space.There are the methods for measuring the vibration experiments transmitted through the shock of the human body by the foundation of forging hammer. There are the results given by the different sorts of accelerations into to special conditions of work in the working space. They are of the vibrometer adding the three directions accelerometer. In this way can be analyze taking into account the vibrations action over the human bodies under the action of the equipment in the working space produced by shocks. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computational modelling of drug infusion into the anisotropic white‐matter tracts of the human brain
Authors: Wagner Arndt , Ehlers Wolfgang 
Published: December 2011

AbstractUnfortunately, the human brain is compromised by an amount of brain diseases, such as strokes or cerebral tumours. In this contribution, special attention is paid to the constitutive modelling procedure and the numerical simulation of the so‐called convection‐enhanced delivery process, where an effective treatment of malignant brain tumours is achieved by bypassing the blood‐brain barrier via a direct infusion of therapeutic agents into the extra‐vascular space of the brain tissue using implanted catheters. The modelling approach of the complex brain‐tissue aggregate proceeds from the Theory of Porous Media including an elastically deformable solid skeleton, provided by the tissue cells and the vascular walls. The tissue is permeated by two liquid phases, the blood and the interstitial fluid. In order to describe a distribution process of the inserted drugs, the interstitial fluid phase is treated as a chemical solution of two components, the liquid solvent and the dissolved therapeutic solute. The inhomogeneous anisotropic nature of the white‐matter tracts is considered by spatially varying permeability tensors, obtained by diffusion‐weighted magnetic resonance imaging. The strongly coupled solid‐liquid transport problem is simultaneously approximated in all primary unknowns using mixed finite elements and solved in a monolithic manner with an implicit time‐integration scheme. The numerical investigation is applied to un‐bloody numerical studies. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multiscale Modeling for the Simulation of Damage Processes at Refractory Materials under Thermal Shock
Authors: Henneberg Dimitri , Ricoeur Andreas 
Published: December 2011

AbstractRefractory materials, for example ceramic materials, initially contain a multitude of defects such as voids, microcracks, grain boundaries etc. The deformation process and failure mechanisms due to thermal shock at high temperatures above 1000°C are going along with the creation of new micro defects as well as the growth and coalescence of cracks. A material damage model based on the theoretical concept of damage mechanics and the mechanics of microcracks is presented in this paper. Cell models are developed as representative volume elements (RVE) including crack initiation and growth as well as microstructural shielding effects. For simple configurations of the microstructure, the relation between stress, strain and temperature is derived from analytical considerations. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A RVE‐based micro mechanical model for short fiber reinforced plastic materials including matrix damage and fiber fracture
Authors: Hoffmann S. , André M. , Rodríguez Sśnchez A. , Mueller R. 
Published: December 2011

AbstractThe representative volume element (RVE) method is applied to a fiber reinforced polymer material undergoing matrix damage and fiber fracture. Results of RVE computations are compared to uniaxial tensile tests performed with the composite material. It is shown that the macroscopic behavior of the composite material can accurately be predicted by RVE computations. (© 2011 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)