All-optical trapping and acceleration of heavy particles

A scheme for fast, compact, and controllable acceleration of heavy particles in vacuum is proposed, in which two counterpropagating lasers with variable frequencies drive a beat-wave structure with variable phase velocity, thus allowing for trapping and acceleration of heavy particles, such as ions or muons. Fine control over the energy distribution and the total charge of the beam is obtained via tuning of the frequency variation. The acceleration scheme is described with a one-dimensional theory, providing the general conditions for trapping and scaling laws for the relevant features of the particle beam. Two-dimensional, electromagnetic particle-in-cell simulations confirm the validity and the robustness of the physical mechanism.Comment: 10 pages, 3 figures, to appear in New Journal of Physic

Dynamics and control of the expansion of finite-size plasmas produced in ultraintense laser-matter interactions

The strong influence of the electron dynamics provides the possibility of controlling the expansion of laser-produced plasmas by appropriately shaping the laser pulse. A simple irradiation scheme is proposed to tailor the explosion of large deuterium clusters, inducing the formation of shock structures, capable of driving nuclear fusion reactions. Such a scenario has been thoroughly investigated, resorting to two- and three-dimensional particle-in-cell simulations. Furthermore, the intricate dynamics of ions and electrons during the collisionless expansion of spherical nanoplasmas has been analyzed in detail using a self-consistent ergodic-kinetic model. This study clarifies the transition from hydrodynamic-like to Coulomb-explosion regimes

Automatic Performance Testing using Input-Sensitive Profiling

During performance testing, software engineers commonly perform application profiling to analyze an application\u27s traces with different inputs to understand performance behaviors, such as time and space consumption. However, a non-trivial application commonly has a large number of inputs, and it is mostly manual to identify the specific inputs leading to performance bottlenecks. Thus, it is challenge is to automate profiling and find these specific inputs. To solve these problems, we propose novel approaches, FOREPOST, GA-Prof and PerfImpact, which automatically profile applications for finding the specific combinations of inputs triggering performance bottlenecks, and further analyze the corresponding traces to identify problematic methods. Specially, our approaches work in two different types of real-world scenarios of performance testing: i) a single-version scenario, in which performance bottlenecks are detected in a single software release, and ii) a two-version scenario, in which code changes responsible for performance regressions are detected by considering two consecutive software releases

Milk fat globule-epidermal growth factor-factor VIII downregulates interleukin-17 expression in sepsis by modulating STAT3 activation

BACKGROUND: Milk fat globule-epidermal growth factor-factor VIII (MFG-E8) is a secretory glycoprotein with a known role in inflammation. In sepsis, interleukin (IL)-17 acts as a proinflammatory cytokine to exaggerate systemic inflammation. We hypothesize that MFG-E8 downregulates IL-17 expression in sepsis. METHODS: Sepsis was induced in 8-week-old male C57BL/6 mice by cecal ligation and puncture (CLP). Recombinant mouse MFG-E8 (rmMFG-E8) at a dosage of 20 mug/kg body weight or phosphate-buffered saline was concurrently injected. After 10 hours, blood and spleen samples were harvested for analysis. For in vitro studies, splenocytes isolated from healthy mice pretreated with rmMFG-E8 and splenocytes from MFG-E8 knockout (mfge8-/-) mice were stimulated with phorbol 12-myristate 13-acetate (PMA) and ionomycin, followed by measurement of IL-17 expression with either quantitative PCR or enzyme-linked immunosorbent assay. RESULTS: At 10 hours after CLP, rmMFG-E8 inhibited the elevated levels of IL-17 protein in serum by 31%, compared with the vehicle. In the spleen, rmMFG-E8 reduced the upregulated IL-17 mRNA and protein levels by 81% and 51%, respectively. This correlated with a significant reduction in organ injury markers AST and ALT in sepsis after administration of rmMFG-E8. In vitro treatment of splenocytes isolated from healthy mice with rmMFG-E8 showed significant downregulation in PMA/ionomycin-induced IL-17 expression. In contrast, CD4 T-cells from mfge8-/- mice showed significant upregulation of IL-17 compared with wild-type mice. The phosphorylated level of signal transducer and activator of transcription 3 (STAT3) was downregulated in spleen tissue of septic mice treated with rmMFG-E8. Conversely, mfge8-/- mice showed increased phosphorylated STAT3 compared with wild-type mice after sepsis. CONCLUSION: Our findings demonstrate MFG-E8-mediated downregulation of IL-17 expression, implicating its potential as a novel therapeutic agent against sepsis

Input-Sensitive Performance Testing

One goal of performance testing is to find specific test input data for exposing performance bottlenecks and identify the methods responsible for these performance bottlenecks. A big and important challenges of performance testing is how to deeply understand the performance behaviors of a non-trivial software system in terms of test input data to properly select the specific test input values for finding the problematic methods. Thus, we propose this research program to automatically analyze performance behaviors in software and link these behaviors with test input data for selecting the specific ones that can expose performance bottlenecks. In addition, this research further examines the corresponding execution traces of selected inputs for targeting the problematic methods

Prediction of bulk milk fatty acid composition based on farming practices collected through on-farm surveys

International audience; The aim of this study was to predict the fatty acid (FA) composition of bulk milk using data describing farming practices collected via on-farm surveys. The FA composition of 1,248 bulk cow milk samples and the related farming practices were collected from 20 experiments led in 10 different European countries at 44 degrees N to 60 degrees N latitude and sea level to 2,000 m altitude. Farming practice-based FA predictions [coefficient of determination (R-2) >0.50] were good for C16:0, C17:0, saturated FA, polyunsaturated FA, and odd-chain FA, and very good (R-2 >= 0.60) for trans-11 C18:1, trans-10 + trans-11 C18:1, cis-9,trans-11 conjugated linoleic acid, total trans FA, C18:3n-3, n-6:n-3 ratio, and branched-chain FA. Fatty acids were predicted by cow diet composition and by the altitude at which milk was produced, whereas animal-related factors (i.e., lactation stage, breed, milk yield, and proportion of primiparous cows in the herd) were not significant in any of the models. Proportion of fresh herbage in the cow diet was the main predictor, with the highest effect in almost all FA models. However, models built solely on conserved forage-derived samples gave good predictions for odd-chain FA, branched-chain FA, trans-10 C18:1 and C18:3n-3 (R-2 >= 0.46, 0.54, 0.52, and 0.70, respectively). These prediction models could offer farmers a valuable tool to help improve the nutritional quality of the milk they produce

Plasmatic and urinary glycosaminoglycans characterization in mucopolysaccharidosis II Patient treated with enzyme-replacement therapy with Idursulfase

We report the structural characterization of plasmatic and urinary GAGs in a Patient affected by MPS II (Hunter syndrome) before and during the first ten months of enzyme-replacement therapy (ERT). Plasmatic GAGs before ERT were rich in pathological DS consisting of iduronic acid (IdoA) and composed of ~90% \uf044Di4s and trace amounts of disulfated disaccharides. DS was also characterized as the main (~90%) urinary GAG mainly composed of ~90% \uf044Di4s with minor percentages of monosulfated and disulfated disaccharides, in particular \u394Di2,4dis. After 300 days of ERT, plasmatic DS strongly decreased but ~14% of IdoA-rich \uf044Di4s was still detected. Similarly, urinary galactosaminoglycans were mainly composed of 78% \uf044Di4s, ~11% \uf044Di6s and ~4% \uf044Di0s with the persistence of \u394Di2,4dis (~4%). About 40% of IdoA-formed \uf044Di4s were also calculated thus confirming that pathological DS is still present in excreted urinary GAGs during ERT. By considering the % of IdoA, we observed rather similar kinetics of excretion in fluids from the beginning of the treatment. Immediately after the first enzyme infusion, a large amount of abnormal DS is removed from tissues reaching the blood compartment and eliminated via the urine, and this process lasts for about two weeks. After this, the percentage of IdoA-rich material present in biological fluids remains fairly constant over the following nine months of treatment. To date, these are the first data regarding plasmatic and urinary kinetics directly measured on products released by the activity of the recombinant enzyme Idursulfase, iduronate-2-sulfatase, evaluated using specific and sensitive analytical procedures