136 research outputs found
Towards efficient data integration and knowledge management in the Agronomic domain
International audienceToday, the revolution in empirical technologies has generated vast amounts of data. This data deluge has created an urgent need to assimilate it with a panoramic view. To this end, information systems play a central role in managing and integrating these data, aiding the biologists in exploiting this integrated information for the extraction of new knowledge. The plant bioinformatics node of the Institut Français de Bioinformatique (IFB) maintains public information systems where a variety of domain specific data are integrated. Currently, efforts are being taken to expose the IFB plant bioinformatics resources as RDF, utilising domain specific ontologies and metadata. Here, we present the overview and the progress of the project
Spectrally reconfigurable quantum emitters enabled by optimized fast modulation
The ability to shape photon emission facilitates strong photon-mediated
interactions between disparate physical systems, thereby enabling applications
in quantum information processing, simulation and communication. Spectral
control in solid state platforms such as color centers, rare earth ions, and
quantum dots is particularly attractive for realizing such applications
on-chip. Here we propose the use of frequency-modulated optical transitions for
spectral engineering of single photon emission. Using a scattering-matrix
formalism, we find that a two-level system, when modulated faster than its
optical lifetime, can be treated as a single-photon source with a widely
reconfigurable photon spectrum that is amenable to standard numerical
optimization techniques. To enable the experimental demonstration of this
spectral control scheme, we investigate the Stark tuning properties of the
silicon vacancy in silicon carbide, a color center with promise for optical
quantum information processing technologies. We find that the silicon vacancy
possesses excellent spectral stability and tuning characteristics, allowing us
to probe its fast modulation regime, observe the theoretically-predicted
two-photon correlations, and demonstrate spectral engineering. Our results
suggest that frequency modulation is a powerful technique for the generation of
new light states with unprecedented control over the spectral and temporal
properties of single photons.Comment: 9 pages, 6 figures; Supplementary Informatio
The Galactic Center with Roman
We advocate for a Galactic center (GC) field to be added to the Galactic
Bulge Time Domain Survey (GBTDS). The new field would yield high-cadence
photometric and astrometric measurements of an unprecedented 3.3
million stars toward the GC. This would enable a wide range of science cases,
such as finding star-compact object binaries that may ultimately merge as
LISA-detectable gravitational wave sources, constraining the mass function of
stars and compact objects in different environments, detecting populations of
microlensing and transiting exoplanets, studying stellar flares and variability
in young and old stars, and monitoring accretion onto the central supermassive
black hole. In addition, high-precision proper motions and parallaxes would
open a new window into the large-scale dynamics of stellar populations at the
GC, yielding insights into the formation and evolution of galactic nuclei and
their co-evolution with the growth of the supermassive black hole. We discuss
the possible trade-offs between the notional GBTDS and the addition of a GC
field with either an optimal or minimal cadence. Ultimately, the addition of a
GC field to the GBTDS would dramatically increase the science return of Roman
and provide a legacy dataset to study the mid-plane and innermost regions of
our Galaxy.Comment: 19 pages, 3 figures. Submitted to the NASA Roman Core Community
Surveys White Paper Cal
Editor's Choice â European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Asymptomatic Lower Limb Peripheral Arterial Disease and Intermittent Claudication
The Science Performance of JWST as Characterized in Commissioning
This paper characterizes the actual science performance of the James Webb
Space Telescope (JWST), as determined from the six month commissioning period.
We summarize the performance of the spacecraft, telescope, science instruments,
and ground system, with an emphasis on differences from pre-launch
expectations. Commissioning has made clear that JWST is fully capable of
achieving the discoveries for which it was built. Moreover, almost across the
board, the science performance of JWST is better than expected; in most cases,
JWST will go deeper faster than expected. The telescope and instrument suite
have demonstrated the sensitivity, stability, image quality, and spectral range
that are necessary to transform our understanding of the cosmos through
observations spanning from near-earth asteroids to the most distant galaxies.Comment: 5th version as accepted to PASP; 31 pages, 18 figures;
https://iopscience.iop.org/article/10.1088/1538-3873/acb29
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 nonâcritically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (nâ=â257), ARB (nâ=â248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; nâ=â10), or no RAS inhibitor (control; nâ=â264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ supportâfree days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ supportâfree days among critically ill patients was 10 (â1 to 16) in the ACE inhibitor group (nâ=â231), 8 (â1 to 17) in the ARB group (nâ=â217), and 12 (0 to 17) in the control group (nâ=â231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ supportâfree days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
Hydrogen storage properties of Mg[BHâ]â
Among the large variety of possible complex hydrides only few exhibit a large gravimetric hydrogen density and stability around 40 kJ molâ»ÂčHâ. Mg[BHâ]â is based on theoretical approaches a complex hydride with an equilibrium hydrogen pressure of approximately 1 bar at room temperature and a hydrogen content of 14.9 mass%. The reaction of Li[BHâ] with MgClâ at elevated temperatures was investigated as a possible route to synthesize Mg[BHâ]â. Li[BHâ] reacts with MgClâ at a temperature >523 K at a pressure of 10 MPa of hydrogen, where the product contains LiCl and Mg[BHâ]â. The desorption pc-isotherm of the product obtained at 623 K shows two flat plateaus, which indicates that the decomposition of the product consists of a two-step reaction. The products of the first and the second decomposition reaction were analyzed by means of X-ray diffraction and found to be MgHâ and Mg, respectively. The enthalpy for the first decomposition reaction was determined to be ÎH = â39.3 kJ molâ»ÂčHâ by the Vanât Hoff plot of the equilibrium measurements between 563 K and 623 K, which is significantly lower than that for pure Li[BHâ] (ÎH = â74.9 kJ molâ»ÂčHâ). However, only the second reaction step (MgHâ â Mg) is reversible at the condition up to 623 K at 10 MPa of hydrogen
Sequential neoadjuvant chemoradiotherapy (CRT) followed by curative surgery vs. primary surgery alone for resectable, non-metastasized pancreatic adenocarcinoma: NEOPA - a randomized multicenter phase III study (NCT01900327, DRKS00003893, ISRCTN82191749)
BACKGROUND: Median OS after surgery in curative intent for non-metastasized pancreas cancer ranges under study conditions from 17.9Â months to 23.6Â months. Tumor recurrence occurs locally, at distant sites (liver, peritoneum, lungs), or both. Observational and autopsy series report local recurrence rates of up to 87% even after potentially âcurativeâ R0 resection. To achieve better local control, neoadjuvant CRT has been suggested for preoperative tumour downsizing, to elevate the likelihood of curative, margin-negative R0 resection and to increase the OS rate. However, controlled, randomized trials addressing the impact of neoadjuvant CRT survival do not exist. METHODS/DESIGN: The underlying hypothesis of this randomized, two-armed, open-label, multicenter, phase III trial is that neoadjuvant CRT increases the three-year overall survival by 12% compared to patients undergoing upfront surgery for resectable pancreatic cancer. A rigorous, standardized technique of histopathologically handling Whipple specimens will be applied at all participating centers. Overall, 410 patients (nâ=â205 in each study arm) will be enrolled in the trial, taking into regard an expected drop out rate of 7% and allocated either to receive neoadjuvant CRT prior to surgery or to undergo surgery alone. Circumferential resection margin status, i.e. R0 and R1 rates, respectively, surgical resectability rate, local and distant disease-free and global survival, and first site of tumor recurrence constitute further essential endpoints of the trial. DISCUSSION: For the first time, the NEOPA study investigates the impact of neoadjuvant CRT on survival of resectable pancreas head cancer in a prospectively randomized manner. The results of the study have the potential to change substantially the treatment regimen of pancreas cancer. TRIAL REGISTRATION: Clinical Trial gov: NCT01900327, DRKS00003893, ISRCTN8219174
Long-term Temperature Measurements of the Upper Troposphere andLowermost Stratosphere with MOZAIC and IAGOS
Investigating Broad Neutralization in HIV-1 Non-B Subtype Infection in Yaoundé, Cameroon
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