2,404 research outputs found
Crosscutting, what is and what is not? A Formal definition based on a Crosscutting Pattern
Crosscutting is usually described in terms of scattering and tangling. However, the distinction between these concepts is vague, which could lead to ambiguous statements. Sometimes, precise definitions are required, e.g. for the formal identification of crosscutting concerns. We propose a conceptual framework for formalizing these concepts based on a crosscutting pattern that shows the mapping between elements at two levels, e.g. concerns and representations of concerns. The definitions of the concepts are formalized in terms of linear algebra, and visualized with matrices and matrix operations. In this way, crosscutting can be clearly distinguished from scattering and tangling. Using linear algebra, we demonstrate that our definition generalizes other definitions of crosscutting as described by Masuhara & Kiczales [21] and Tonella and Ceccato [28]. The framework can be applied across several refinement levels assuring traceability of crosscutting concerns. Usability of the framework is illustrated by means of applying it to several areas such as change impact analysis, identification of crosscutting at early phases of software development and in the area of model driven software development
Adaptive Controller Placement for Wireless Sensor-Actuator Networks with Erasure Channels
Wireless sensor-actuator networks offer flexibility for control design. One
novel element which may arise in networks with multiple nodes is that the role
of some nodes does not need to be fixed. In particular, there is no need to
pre-allocate which nodes assume controller functions and which ones merely
relay data. We present a flexible architecture for networked control using
multiple nodes connected in series over analog erasure channels without
acknowledgments. The control architecture proposed adapts to changes in network
conditions, by allowing the role played by individual nodes to depend upon
transmission outcomes. We adopt stochastic models for transmission outcomes and
characterize the distribution of controller location and the covariance of
system states. Simulation results illustrate that the proposed architecture has
the potential to give better performance than limiting control calculations to
be carried out at a fixed node.Comment: 10 pages, 8 figures, to be published in Automatic
Thermodynamics of nuclei in thermal contact
The behaviour of a di-nuclear system in the regime of strong pairing
correlations is studied with the methods of statistical mechanics. It is shown
that the thermal averaging is strong enough to assure the application of
thermodynamical methods to the energy exchange between the two nuclei in
contact. In particular, thermal averaging justifies the definition of a nuclear
temperature.Comment: 9 pages, 1 figur
Cold exposure induces dynamic changes in circulating triacylglycerol species, which is dependent on intracellular lipolysis: A randomized cross-over trial
Background The application of cold exposure has emerged as an approach to enhance whole-body lipid catabolism.
The global effect of cold exposure on the lipidome in humans has been reported with mixed results depending on
intensity and duration of cold.
Methods This secondary study was based on data from a previous randomized cross-over trial (ClinicalTrials.gov ID:
NCT03012113). We performed sequential lipidomic profiling in serum during 120 min cold exposure of human
volunteers. Next, the intracellular lipolysis was blocked in mice (eighteen 10-week-old male wild-type mice C57BL/
6J) using a small-molecule inhibitor of adipose triglyceride lipase (ATGL; Atglistatin), and mice were exposed to
cold for a similar duration. The quantitative lipidomic profiling was assessed in-depth using the Lipidyzer platform.
Findings In humans, cold exposure gradually increased circulating free fatty acids reaching a maximum at 60 min,
and transiently decreased total triacylglycerols (TAGs) only at 30 min. A broad range of TAG species was initially
decreased, in particular unsaturated and polyunsaturated TAG species with ≤5 double bonds, while after 120 min a
significant increase was observed for polyunsaturated TAG species with ≥6 double bonds in humans. The mechanistic
study in mice revealed that the cold-induced increase in polyunsaturated TAGs was largely prevented by
blocking adipose triglyceride lipase.
Interpretation We interpret these findings as that cold exposure feeds thermogenic tissues with TAG-derived fatty
acids for combustion, resulting in a decrease of circulating TAG species, followed by increased hepatic production
of polyunsaturated TAG species induced by liberation of free fatty acids stemming from adipose tissue.Netherlands CardioVascular Research Initiative: `the Dutch Heart FoundationDutch Federation of University Medical CentersNetherlands Organization for Health Research and Development
Royal Netherlands Academy of Sciences' CVON201720 GENIUS-IIFundacion Alfonso Martin EscuderoMaria Zambrano - Ministerio de Universidades y la Union Europea -NextGenerationEU RR_C_2021_04Spanish Government FPU19/01609European Foundation for the Study of Diabetes (EFSD)NWO XOmics project 184.034.01
Modulation of Host Immunity by Human Respiratory Syncytial Virus Virulence Factors: A Synergic Inhibition of Both Innate and Adaptive Immunity
Indexación: Web of Science; Scopus.The Human Respiratory Syncytial Virus (hRSV) is a major cause of acute lower respiratory tract infections (ARTIs) and high rates of hospitalizations in children and in the elderly worldwide. Symptoms of hRSV infection include bronchiolitis and pneumonia. The lung pathology observed during hRSV infection is due in part to an exacerbated host immune response, characterized by immune cell infiltration to the lungs. HRSV is an enveloped virus, a member of the Pneumoviridae family, with a non-segmented genome and negative polarity-single RNA that contains 10 genes encoding for 11 proteins. These include the Fusion protein (F), the Glycoprotein (G), and the Small Hydrophobic (SH) protein, which are located on the virus surface. In addition, the Nucleoprotein (N), Phosphoprotein (P) large polymerase protein (L) part of the RNA-dependent RNA polymerase complex, the M2-1 protein as a transcription elongation factor, the M2-2 protein as a regulator of viral transcription and (M) protein all of which locate inside the virion. Apart from the structural proteins, the hRSV genome encodes for the non-structural 1 and 2 proteins (NS1 and NS2). HRSV has developed different strategies to evade the host immunity by means of the function of some of these proteins that work as virulence factors to improve the infection in the lung tissue. Also, hRSV NS-1 and NS-2 proteins have been shown to inhibit the activation of the type I interferon response. Furthermore, the hRSV nucleoprotein has been shown to inhibit the immunological synapsis between the dendritic cells and T cells during infection, resulting in an inefficient T cell activation. Here, we discuss the hRSV virulence factors and the host immunological features raised during infection with this virus.https://www.frontiersin.org/articles/10.3389/fcimb.2017.00367/ful
Microstructure observations during the spring 2011 STRATIPHYT-II cruise in the Northeast Atlantic
Small-scale temperature and conductivity variations have been measured in the upper 100 m of the northeast Atlantic during the STRATIPHYT-II cruise (Las Palmas–Reykjavik, 6 April–3 May 2011). The measurements were done at midday and comprised 2 to 15 vertical profiles at each station. The derived turbulent quantities show a transition between weakly-stratified (mixed layer depth, MLD, <100) and well-mixed waters (MLD > 100), which was centered at about 48° N. The temperature eddy diffusivities, <I>K<sub>T</sub></I>, range from 10<sup>&minus;5</sup> to 10<sup>0</sup> m<sup>2</sup> s<sup>−1</sup> in the weakly-stratified stations, and range from 3 &times; 10<sup>&minus;4</sup> to 2 &times; 10<sup>0</sup> m<sup>2</sup> s<sup>−1</sup> in the well-mixed stations. The turbulent kinetic energy dissipation rates, ε, range from 3 &times; 10<sup>&minus;8</sup> to 2 &times; 10<sup>&minus;6</sup> m<sup>2</sup> s<sup>−3</sup> south of the transition zone, and from 10<sup>&minus;7</sup> to 10<sup>&minus;5</sup> m<sup>2</sup> s<sup>−3</sup> north of the transition zone. The station-averaged <I>K<sub>T</sub></I> values throughout the mixed layer increase exponentially with the wind speed. The station-averaged ε values throughout the mixed layer scale with the wind stress similarity variable with a scaling factor of about 1.8 in the wind-dominated stations (&epsilon; &approx; 1.8 <I>u</I><sub>&star;</sub><sup>3</sup>/(&minus;&kappa;<I>z</I>)). The values of <I>K<sub>T</sub></I> and ε are on average 10 times higher compared to the values measured at the same stations in July 2009. The results presented here constitute a unique data set giving large spatial coverage of upper ocean spring turbulence quantities
Implications of modeling seasonal differences in the extremal dependence of rainfall maxima
For modeling extreme rainfall, the widely used Brown–Resnick max-stable model extends the concept of the variogram to suit block maxima, allowing the explicit modeling of the extremal dependence shown by the spatial data. This extremal dependence stems from the geometrical characteristics of the observed rainfall, which is associated with different meteorological processes and is usually considered to be constant when designing the model for a study. However, depending on the region, this dependence can change throughout the year, as the prevailing meteorological conditions that drive the rainfall generation process change with the season. Therefore, this study analyzes the impact of the seasonal change in extremal dependence for the modeling of annual block maxima in the Berlin-Brandenburg region. For this study, two seasons were considered as proxies for different dominant meteorological conditions: summer for convective rainfall and winter for frontal/stratiform rainfall. Using maxima from both seasons, we compared the skill of a linear model with spatial covariates (that assumed spatial independence) with the skill of a Brown–Resnick max-stable model. This comparison showed a considerable difference between seasons, with the isotropic Brown–Resnick model showing considerable loss of skill for the winter maxima. We conclude that the assumptions commonly made when using the Brown–Resnick model are appropriate for modeling summer (i.e., convective) events, but further work should be done for modeling other types of precipitation regimes
On the influence of drag force modeling in long-span suspension bridge flutter analysis
The present study aimed at investigating the role played by the description of the drag component on the predicted flutter velocity (and frequency) of very long-span suspension bridges. Based on a detailed finite element model of the central span of the Akashi Kaikyo Bridge, implemented in ANSYS, flutter analyses were run according to the following descriptions of the wind aerodynamic actions: (a) unsteady lift, moment and drag; (b) unsteady lift and moment plus steady drag, and (c) unsteady lift and moment, without drag. The finite element results are compared with those obtained by an in-house MATLAB code based on a semi-analytic continuum model. The latter includes flexural-torsional second-order effects induced by steady drag force in the bridge’s equations of motion, in addition to the unsteady lift and moment actions
Estudio de una ecuación del calor semilineal en dominios no-cilÃndricos
En esta comunicación presentaremos resultados de existencia y unicidad de soluciones que verifican una igualdad de energÃa para una ecuación semilineal en dominios no-cilÃndricos (cf. [P. E. Kloeden, P. MarÃn-Rubio and J. Real, Pullback attractors for a semilinear heat equation in a
non-cylindrical domain, J. Differential Equations 244 (2008), 2062–2090]) basándonos en algunas ideas de [M. L. Bernardi, G. A. Pozzi and G. Savaré, Variational equations of Schroedinger-type in noncylindrical domains, J. Differential Equations 171 (2001), 63–87. S. Bonaccorsi and G. Guatteri, A variational approach to evolution problems with variable domains,
J. Differential Equations 175 (2001), 51–70]. En la prueba se usa un método de penalización para un problema más regular y paso al lÃmite. Tras ello, y con hipótesis adicionales, se consiguen estimaciones uniformes que permiten estudiar el comportamiento asintótico del problema.Ministerio de Educación y Ciencia (MEC). Españ
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