At the National Ignition Facility, inertial confinement fusion experiments aim to burn and ignite a hydrogen plasma to generate a net source of energy through the fusion of deuterium and tritium ...ions. The energy deposited by α-particles released from the deuterium–tritium fusion reaction plays the central role in heating the fuel to achieve a sustained thermonuclear burn. In the hydrodynamic picture, α-heating increases the temperature of the plasma, leading to increased reactivity because the mean ion kinetic energy increases. Therefore, the ion temperature is related to the mean ion kinetic energy. Here we use the moments of the neutron spectrum to study the relationship between the ion temperature (measured by the variance in the neutron kinetic energy spectrum) and the ion mean kinetic energy (measured by the shift in the mean neutron energy). We observe a departure from the relationship expected for plasmas where the ion relative kinetic energy distribution is Maxwell–Boltzmann, when the plasma begins to burn. Understanding the cause of this departure from hydrodynamic behaviour could be important for achieving robust and reproducible ignition.Inertial confinement fusion experiments reveal a departure from the expected hydrodynamic behaviour of a plasma when the fusion reactions become the primary source of plasma heating.
Inertial confinement fusion implosions designed to have minimal fluid motion at peak compression often show significant linear flows in the laboratory, attributable per simulations to percent-level ...imbalances in the laser drive illumination symmetry. We present experimental results which intentionally varied the mode 1 drive imbalance by up to 4% to test hydrodynamic predictions of flows and the resultant imploded core asymmetries and performance, as measured by a combination of DT neutron spectroscopy and high-resolution x-ray core imaging. Neutron yields decrease by up to 50%, and anisotropic neutron Doppler broadening increases by 20%, in agreement with simulations. Furthermore, a tracer jet from the capsule fill-tube perturbation that is entrained by the hot-spot flow confirms the average flow speeds deduced from neutron spectroscopy.
•Annual gross ecosystem production and respiration correlated with elevation.•Timing and volume of snow cover affected the annual carbon balance.•Without snow cover, carbon uptake was controlled by ...(soil) temperature.•Foehn frequency represents a regional climate signal for ecosystem processes.
The 2013/2014 winter season showed exceptionally sparse snow cover conditions north of the Alps, which allowed an in situ investigation of the response of vegetation to changed environmental conditions. Examination of carbon dioxide fluxes at three grassland sites along an elevation gradient from 595 to 864ma.m.s.l. revealed that elevation, snow cover extent, soil temperature (Tsoil) and management were determinative factors for productivity. In the absence of snow cover at the highest elevation site (864m), substantial growth started only when the mean daily Tsoil exceeded 5°C. The lack of snow cover at the lowest elevation site (595m) allowed the vegetation to remain photosynthetically active throughout the winter, with a canopy that developed after the last harvest of the previous season. The reduced snow cover at the lower elevation sites (595 and 769m) resulted in an earlier spring, a significant increase in gross ecosystem production and ecosystem respiration, as well as enhanced seasonal carbon dioxide uptake. The reduced snow cover in the 2013/2014 winter season is attributed to low precipitation and high energy influx, which in turn were best explained by exceptionally frequent foehn, i.e., southern advection of dry, warm air across the Alps.
Central venous catheter (CVC)-related bloodstream infections (CRBSI) are a frequent cause of morbidity and mortality in patients with chemotherapy-induced neutropenia. Chlorhexidine containing ...catheter securement dressings may prevent CRBSI.
A multicenter randomized, controlled trial was conducted at 10 German hematology departments. We compared chlorhexidine-containing dressings with non-chlorhexidine control dressings in neutropenic patients. The primary end point was the incidence of definite CRBSI within the first 14 days (dCRBSI14) of CVC placement. Secondary end points included combined incidence of definite or probable CRBSI within 14 days (dpCRBSI14), overall (dpCRBSI), incidence of unscheduled dressing changes and adverse events.
From February 2012 to September 2014, 613 assessable patients were included in the study. The incidence of dCRBSI14 was 2.6% (8/307) in the chlorhexidine and 3.9% (12/306) in the control group (P = 0.375). Both dpCRBSI14 and dpCRBSI were significantly less frequent in the study group with dpCRBSI14 in 6.5% (20/307) of the chlorhexidine group when compared with 11% (34/306) in the control group (P = 0.047), and dpCRBSI in 10.4% (32/307) versus 17% (52/306), respectively (P = 0.019). The frequency of dressing intolerance with cutaneous and soft tissue abnormalities at the contact area was similar in both groups (12.4% and 11.8%; P = 0.901).
Although the trial failed its primary end point, the application of chlorhexidine containing catheter securement dressings reduces the incidence of definite or probable CRBSI in neutropenic patients.
NCT01544686 (Clinicaltrials.gov).
The PathoSystems Resource Integration Center (PATRIC) is one of eight Bioinformatics Resource Centers (BRCs) funded by the National Institute of Allergy and Infection Diseases (NIAID) to create a ...data and analysis resource for selected NIAID priority pathogens, specifically proteobacteria of the genera Brucella, Rickettsia and Coxiella, and corona-, calici- and lyssaviruses and viruses associated with hepatitis A and E. The goal of the project is to provide a comprehensive bioinformatics resource for these pathogens, including consistently annotated genome, proteome and metabolic pathway data to facilitate research into counter-measures, including drugs, vaccines and diagnostics. The project's curation strategy has three prongs: 'breadth first' beginning with whole-genome and proteome curation using standardized protocols, a 'targeted' approach addressing the specific needs of researchers and an integrative strategy to leverage high-throughput experimental data (e.g. microarrays, proteomics) and literature. The PATRIC infrastructure consists of a relational database, analytical pipelines and a website which supports browsing, querying, data visualization and the ability to download raw and curated data in standard formats. At present, the site warehouses complete sequences for 17 bacterial and 332 viral genomes. The PATRIC website (https://patric.vbi.vt.edu) will continually grow with the addition of data, analysis and functionality over the course of the project.
Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant ...improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100 </~ keV. To describe the spectrum, we have developed an R-matrix model that accounts for interferences from fermion symmetry and intermediate states, and show these effects to be non-negligible. We also find the spectrum can be described by sequential decay through ℓ=1 states in (5)He, which differs from previous interpretations.
Myeloid-derived suppressor cells (MDSCs) represent a heterogeneous population that shares certain characteristics including an aberrant myeloid phenotype and the ability to suppress T cells. MDSCs ...have been predominantly studied in malignant diseases and findings suggest involvement in tumor-associated immune suppression. Chronic lymphocytic leukemia (CLL) is the leukemia with the highest incidence among adults. Immune defects occur already at early disease stages and impact the clinical course. We assessed presence, frequency, association to other immune parameters, and functional properties of circulating CD14+ cells lacking HLA-DR expression (HLA-DRlo) in patients with untreated CLL. These monocytic cells represent one of the best-defined human MDSC subsets. Frequency of CD14+HLA-DRlo cells was significantly increased in CLL patients. Furthermore, MDSCs suppressed in vitro T-cell activation and induced suppressive regulatory T cells (TRegs). The MDSC-mediated modulation of T cells could be attributed to their increased indoleamine 2,3-dioxygenase (IDO) activity. CLL cells induced IDOhi MDSCs from healthy donor monocytes suggesting bidirectional crosstalk between CLL-cells, MDSCs, and TRegs. Overall, we identified a MDSC population that expands in CLL. The exact mechanisms responsible for such accumulation remain to be elucidated and it will be of interest to test whether antagonizing suppressive functions of CLL MDSCs could represent a mean for enhancing immune responses.
•Monocytic IDOhi MDSCs are increased in CLL patients, suppress T cells, and promote TReg induction.•CLL cells induce conversion of monocytes into MDSCs suggesting bidirectional crosstalk between CLL cells, MDSCs, and TRegs.
Radial glial cells are characterized, besides their astroglial properties, by long radial processes extending from the ventricular zone to the pial surface, a crucial feature for the radial migration ...of neurons. The molecular signals that regulate this characteristic morphology, however, are largely unknown. We show an important role of the secreted molecule reelin for the establishment of radial glia processes. We describe a significant reduction in ventricular zone cells with long radial processes in the absence of reelin in the cortex of reeler mutant mice. These defects were correlated to a decrease in the content of brain lipid-binding protein (Blbp) and were detected exclusively in the cerebral cortex, but not in the basal ganglia of reeler mice. Conversely, reelin addition in vitro increased the Blbp content and process extension of radial glia from the cortex, but not the basal ganglia. Isolation of radial glia by fluorescent-activated cell sorting showed that these effects are due to direct signaling of reelin to radial glial cells. We could further demonstrate that this signaling requires Dab1, as the increase in Blbp upon reelin addition failed to occur in Dab1 -/- mice. Taken together, these results unravel a novel role of reelin signaling to radial glial cells that is crucial for the regulation of their Blbp content and characteristic morphology in a region-specific manner.
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