973 resultados para Coordinates, Trilinear.


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Background: Mammalian target of rapamycin (mTOR), a central regulator of cell growth, is found in two structurally and functionally distinct multiprotein complexes called mTOR complex (mTORC)1 and mTORC2. The specific roles of each of these branches of mTOR signaling have not been dissected in the adult heart. In the present study, we aimed to bring new insights into the function of cardiac mTORC1-mediated signaling in physiological as well as pathological situations.Methods: We generated mice homozygous for loxP-flanked raptor and positive for the tamoxifen-inducible Cre recombinase (MerCreMer) under control of the α- myosin heavy chain promoter. The raptor gene encodes an essential component of mTORC1. Gene ablation was induced at the age of 10-12 weeks, and two weeks later the raptor cardiac-knockout (raptor-cKO) mice started voluntary cagewheel exercise or were subjected to transverse aortic constriction (TAC) to induce pressure overload.Results: In sedentary raptor-cKO mice, ejection fractions gradually decreased, resulting in significantly reduced values at 38 days (P < 0.001). Raptor-cKO mice started to die during the fifth week after the last tamoxifen injection. At that time, the mortality rate was 36% in sedentary (n = 11) and 64% in exercising (n = 14) mice. TAC-induced pressure overload resulted in severe cardiac dysfunction already at earlier timepoints. Thus, at 7-9 days after surgery, ejection fraction and fractional shortening values were 22.3% vs 43.5% and 10.2% vs 21.5% in raptor-cKO vs wild-type mice, respectively. This was accompanied by significant reductions of ventricular wall and septal thickness as well as an increase in left ventricular internal diameter. Moreover, ventricular weight to tibial length ratios were increased in wild-type, but not in the raptor-cKO TAC mice. Together, this shows that raptor-cKO mice rapidly developed dilated cardiomyopathy without going through a phase of adaptive hypertrophy. Expression of ANP and β-MHC was induced in all raptor-cKO mice irrespective of the cardiac load conditions. Consistent with reduced mTORC1 activity, phosphorylation of ribosomal S6 kinase and 4E-BP1 was blunted, indicating reduced protein synthesis. Moreover, expression of multiple genes involved in the regulation of energy metabolism was altered, and followed by a shift from fatty acid to glucose oxidation.Conclusion: Our study suggests that mTORC1 coordinates protein and energy metabolic pathways in the heart. Moreover, we demonstrate that raptor is essential for the cardiac adaptation to increased workload and importantly, also for normal physiological cardiac function.

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A clear and rigorous definition of muscle moment-arms in the context of musculoskeletal systems modelling is presented, using classical mechanics and screw theory. The definition provides an alternative to the tendon excursion method, which can lead to incorrect moment-arms if used inappropriately due to its dependency on the choice of joint coordinates. The definition of moment-arms, and the presented construction method, apply to musculoskeletal models in which the bones are modelled as rigid bodies, the joints are modelled as ideal mechanical joints and the muscles are modelled as massless, frictionless cables wrapping over the bony protrusions, approximated using geometric surfaces. In this context, the definition is independent of any coordinate choice. It is then used to solve a muscle-force estimation problem for a simple 2D conceptual model and compared with an incorrect application of the tendon excursion method. The relative errors between the two solutions vary between 0% and 100%.

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PURPOSE: The aim of this study was to develop models based on kernel regression and probability estimation in order to predict and map IRC in Switzerland by taking into account all of the following: architectural factors, spatial relationships between the measurements, as well as geological information. METHODS: We looked at about 240,000 IRC measurements carried out in about 150,000 houses. As predictor variables we included: building type, foundation type, year of construction, detector type, geographical coordinates, altitude, temperature and lithology into the kernel estimation models. We developed predictive maps as well as a map of the local probability to exceed 300 Bq/m(3). Additionally, we developed a map of a confidence index in order to estimate the reliability of the probability map. RESULTS: Our models were able to explain 28% of the variations of IRC data. All variables added information to the model. The model estimation revealed a bandwidth for each variable, making it possible to characterize the influence of each variable on the IRC estimation. Furthermore, we assessed the mapping characteristics of kernel estimation overall as well as by municipality. Overall, our model reproduces spatial IRC patterns which were already obtained earlier. On the municipal level, we could show that our model accounts well for IRC trends within municipal boundaries. Finally, we found that different building characteristics result in different IRC maps. Maps corresponding to detached houses with concrete foundations indicate systematically smaller IRC than maps corresponding to farms with earth foundation. CONCLUSIONS: IRC mapping based on kernel estimation is a powerful tool to predict and analyze IRC on a large-scale as well as on a local level. This approach enables to develop tailor-made maps for different architectural elements and measurement conditions and to account at the same time for geological information and spatial relations between IRC measurements.

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In the main report concerning the role that magnesium may have in highway concrete aggregate, over 20,000 electron microprobe data were obtained, primarily from automated scans, or traverses, across dolomite aggregate grains and the adjacent cement paste. Representative traverses were shown in figures and averages of the data were presented in Table II. In this Appendix, detailed representative and selected analyses of carbonate aggregate only are presented. These analyses were not presented in the main report because they would be interesting to only a few specialists in dolomite· rocks. In this Appendix, individual point analyses of mineral compositions in the paste have been omitted along with dolomite compositions at grain boundaries and cracks. Clay minerals and quartz inclusions in the aggregate are also not included. In the analyses, the first three column headings from left to right show line number, x-axis, and y-axis (Line number is an artifact of the computer print-out for each new traverse. Consecutive line numbers indicate a continuous traverse with distances between each point of 1.5 to a few μ-m. X-axis and y-axis are coordinates on the electron microscope stage). The next columns present weight percent oxide content of FeO, K20, CaO, Si02, Al203, MgO, SrO, BaO, MnO, Na20, and C02 (calculated assuming the number of moles of C02 is equal to the sum of moles of oxides, chiefly CaO and MgO), TOTAL (the sum of all oxides), and total (sum of all oxides excluding COi). In many of the analyses total is omitted.

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Cell motility is an essential process that depends on a coherent, cross-linked actin cytoskeleton that physically coordinates the actions of numerous structural and signaling molecules. The actin cross-linking protein, filamin (Fln), has been implicated in the support of three-dimensional cortical actin networks capable of both maintaining cellular integrity and withstanding large forces. Although numerous studies have examined cells lacking one of the multiple Fln isoforms, compensatory mechanisms can mask novel phenotypes only observable by further Fln depletion. Indeed, shRNA-mediated knockdown of FlnA in FlnB¿/¿ mouse embryonic fibroblasts (MEFs) causes a novel endoplasmic spreading deficiency as detected by endoplasmic reticulum markers. Microtubule (MT) extension rates are also decreased but not by peripheral actin flow, because this is also decreased in the Fln-depleted system. Additionally, Fln-depleted MEFs exhibit decreased adhesion stability that appears in increased ruffling of the cell edge, reduced adhesion size, transient traction forces, and decreased stress fibers. FlnA¿/¿ MEFs, but not FlnB¿/¿ MEFs, also show a moderate defect in endoplasm spreading, characterized by initial extension followed by abrupt retractions and stress fiber fracture. FlnA localizes to actin linkages surrounding the endoplasm, adhesions, and stress fibers. Thus we suggest that Flns have a major role in the maintenance of actin-based mechanical linkages that enable endoplasmic spreading and MT extension as well as sustained traction forces and mature focal adhesions.

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L'algorisme de McLachlan per a l'alineament de dos conjunts de coordenades atòmiques és interpretat sota l'òptica de l'Anàlisi Multivariant, que posa de manifest que el plantejament d'aquest problema és equivalent al de l'anàlisi de Procrustes i que la solució proposada per Kabsch és anàloga a la de Sibson, desenvolupada independentment

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This report describes a short-term study undertaken to investigate the potential for using dense three-dimensional (3D) point clouds generated from light detection and ranging (LIDAR) and photogrammetry to assess roadway roughness. Spatially continuous roughness maps have potential for the identification of localized roughness features, which would be a significant improvement over traditional profiling methods. This report specifically illustrates the use of terrestrial laser scanning (TLS) and photogrammetry using a process known as structure from motion (SFM) to acquire point clouds and illustrates the use of these point clouds in evaluating road roughness. Five roadway sections were chosen for scanning and testing: three gravel road sections, one portland cement concrete (PCC) section, and one asphalt concrete (AC) section. To compare clouds obtained from terrestrial laser scanning and photogrammetry, the coordinates of the clouds for the same section on the same date were matched using open source computer code. The research indicates that the technologies described are very promising for evaluating road roughness. The major advantage of both technologies is the large amount of data collected, which allows the evaluation of the full surface. Additional research is needed to further develop the use of dense 3D point clouds for roadway assessment.

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Global positioning systems (GPS) offer a cost-effective and efficient method to input and update transportation data. The spatial location of objects provided by GPS is easily integrated into geographic information systems (GIS). The storage, manipulation, and analysis of spatial data are also relatively simple in a GIS. However, many data storage and reporting methods at transportation agencies rely on linear referencing methods (LRMs); consequently, GPS data must be able to link with linear referencing. Unfortunately, the two systems are fundamentally incompatible in the way data are collected, integrated, and manipulated. In order for the spatial data collected using GPS to be integrated into a linear referencing system or shared among LRMs, a number of issues need to be addressed. This report documents and evaluates several of those issues and offers recommendations. In order to evaluate the issues associated with integrating GPS data with a LRM, a pilot study was created. To perform the pilot study, point features, a linear datum, and a spatial representation of a LRM were created for six test roadway segments that were located within the boundaries of the pilot study conducted by the Iowa Department of Transportation linear referencing system project team. Various issues in integrating point features with a LRM or between LRMs are discussed and recommendations provided. The accuracy of the GPS is discussed, including issues such as point features mapping to the wrong segment. Another topic is the loss of spatial information that occurs when a three-dimensional or two-dimensional spatial point feature is converted to a one-dimensional representation on a LRM. Recommendations such as storing point features as spatial objects if necessary or preserving information such as coordinates and elevation are suggested. The lack of spatial accuracy characteristic of most cartography, on which LRM are often based, is another topic discussed. The associated issues include linear and horizontal offset error. The final topic discussed is some of the issues in transferring point feature data between LRMs.

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A comment about the article “Local sensitivity analysis for compositional data with application to soil texture in hydrologic modelling” writen by L. Loosvelt and co-authors. The present comment is centered in three specific points. The first one is related to the fact that the authors avoid the use of ilr-coordinates. The second one refers to some generalization of sensitivity analysis when input parameters are compositional. The third tries to show that the role of the Dirichlet distribution in the sensitivity analysis is irrelevant

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Successful pregnancy depends on well coordinated developmental events involving both maternal and embryonic components. Although a host of signaling pathways participate in implantation, decidualization, and placentation, whether there is a common molecular link that coordinates these processes remains unknown. By exploiting genetic, molecular, pharmacological, and physiological approaches, we show here that the nuclear transcription factor peroxisome proliferator-activated receptor (PPAR) delta plays a central role at various stages of pregnancy, whereas maternal PPARdelta is critical to implantation and decidualization, and embryonic PPARdelta is vital for placentation. Using trophoblast stem cells, we further elucidate that a reciprocal relationship between PPARdelta-AKT and leukemia inhibitory factor-STAT3 signaling pathways serves as a cell lineage sensor to direct trophoblast cell fates during placentation. This novel finding of stage-specific integration of maternal and embryonic PPARdelta signaling provides evidence that PPARdelta is a molecular link that coordinates implantation, decidualization, and placentation crucial to pregnancy success. This study is clinically relevant because deferral of on time implantation leads to spontaneous pregnancy loss, and defective trophoblast invasion is one cause of preeclampsia in humans.

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The Volunteer Ombudsman Program places volunteers in long-term care facilities across Iowa to assist the state’s team of Local Long- Term Care Ombudsmen carry out the duties of the Older Americans Act of 1965. The Office of the State Long-Term Care Ombudsman coordinates the Volunteer Ombudsman Program (VOP) to train and certify individuals who are interested in listening, empowering and serving as a voice for long-term care residents. Unlike facility volunteers, VOP volunteers do not assist residents with daily activities. Rather, they are responsible for making several unannounced visits to a specific facility each month to talk to residents and family members and identify concerns.

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A conditional heat-sensitive mutation in the cdc14 gene of the fission yeast Schizosaccharomyces pombe results in failure to form a septum. Cells become highly elongated and multinucleate as growth and nuclear division continue in the absence of cell division. This article describes the cloning of the cdc14 gene and the identification of its product, a protein of 240 amino acids, p28cdc14. A null allele of the cdc14 gene shows that the gene is essential for septum formation and completion of the cell-division cycle. Overexpression of the gene product, p28cdc14, causes cell-cycle arrest in late G2 before mitosis. Cells leaking past the block activate p34cdc2 kinase and show condensed chromosomes, but the normal rearrangements of the microtubules and microfilaments that are associated with the transition from interphase to mitosis do not occur. Overexpression of p28cdc14 in mutants, in which the timing of mitosis is altered, suggests that these effects may be mediated upstream of the mitotic inhibitor wee1. These data are consistent with the idea that p28cdc14 may play a role in both the initiation of mitosis and septum formation and, by doing so, be part of the mechanism that coordinates these two cell-cycle events.

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The NS5A protein of HCV is an essential component of the viral RNA replication machinery and may also function in modulation of the host cell environment. The exact function of NS5A in these processes remains unknown. NS5A is a large hydrophilic phosphoprotein protein consisting of three domains. The amino-terminal domain, designated domain I, coordinates a single zinc atom that is required for virus replication. We have determined the X-ray crystallographic structure of the domain I region of NS5A, and the structure sheds some light on the previously reported RNA binding activity observed for NS5A and suggests that the protein functions as a dimer. Here we describe the bacterial expression, purification, crystallization, and structural determination of the amino-terminal domain I of NS5A. The methods described herein should be of use for the generation of domain I for biochemical studies as well as future crystallization studies as antiviral compounds directed against this region of NS5A become available.

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This paper presents the general regression neural networks (GRNN) as a nonlinear regression method for the interpolation of monthly wind speeds in complex Alpine orography. GRNN is trained using data coming from Swiss meteorological networks to learn the statistical relationship between topographic features and wind speed. The terrain convexity, slope and exposure are considered by extracting features from the digital elevation model at different spatial scales using specialised convolution filters. A database of gridded monthly wind speeds is then constructed by applying GRNN in prediction mode during the period 1968-2008. This study demonstrates that using topographic features as inputs in GRNN significantly reduces cross-validation errors with respect to low-dimensional models integrating only geographical coordinates and terrain height for the interpolation of wind speed. The spatial predictability of wind speed is found to be lower in summer than in winter due to more complex and weaker wind-topography relationships. The relevance of these relationships is studied using an adaptive version of the GRNN algorithm which allows to select the useful terrain features by eliminating the noisy ones. This research provides a framework for extending the low-dimensional interpolation models to high-dimensional spaces by integrating additional features accounting for the topographic conditions at multiple spatial scales. Copyright (c) 2012 Royal Meteorological Society.

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To elucidate the structural basis of T cell recognition of hapten-modified antigenic peptides, we studied the interaction of the T1 T cell antigen receptor (TCR) with its ligand, the H-2Kd-bound Plasmodium berghei circumsporozoite peptide 252-260 (SYIPSAEKI) containing photoreactive 4-azidobenzoic acid (ABA) on P. berghei circumsporozoite Lys259. The photoaffinity-labeled TCR residue(s) were mapped as Tyr48 and/or Tyr50 of complementary determining region 2beta (CDR2beta). Other TCR-ligand contacts were identified by mutational analysis. Molecular modeling, based on crystallographic coordinates of closely related TCR and major histocompatibility complex I molecules, indicated that ABA binds strongly and specifically in a cavity between CDR3alpha and CDR2beta. We conclude that TCR expressing selective Vbeta and CDR3alpha sequences form a binding domain between CDR3alpha and CDR2beta that can accommodate nonpeptidic moieties conjugated at the C-terminal portion of peptides binding to major histocompatibility complex (MHC) encoded proteins.