96 research outputs found
Compact Laser Communication Terminal Architecture and In-Orbit Demonstration
Satellites are generating more data than ever due to more demanding payloads, although communications Down To Earth (DTE) have not experienced the same growth in data rates. Compact Laser Communication Terminals are a promising technology that will increase bandwidths (10 Gbit+) and pave the way for larger data volumes to be transmitted which will increase the relevance of small and CubeSats in space data as service offerings. The in-orbit demonstrator is targeting a downlink data rate of 1 Gbit/s with a range of up to 1000km. A downlink wavelength of 1545nm is used while 1590nm is used for the ground station beacon. PRBS23 sequences will be transmitted from the in-orbit terminal to a ground station in the Netherlands. During in-orbit experimentation, attempts will be made to acquire payload data from other onboard payloads and to forward this data down to earth. This will provide valuable insight into possible future enhancements.
The goal is to use the lessons learned from the in-orbit demonstration and results to drive the development of future iterations of the terminal. Lessons learned during the development phase, market feedback and test results are already being used to shape the architecture and design of the system. The following learnings are anticipated: robust fast data storage does add value; higher down and upload speeds are required; throughput enhancement using adjustable data rates will be worth the investment and enhancing error correction allows for more efficient transfers
Towards the Use of Commercial-off-the-Shelf Small-Satellite Components for Deep-Space CubeSats: a Feasibility and Performance Analysis
The aim of this paper is to assess the feasibility of using currently available commercial-off-the-shelf (COTS) small-satellites components in deep-space scenarios, studying their applicability and performance. To evaluate the performances, an asteroid fly-by mission is briefly introduced, but several of the selection criteria and ideas can be extended to other deep space mission concepts. This particular mission scenario requires to follow three main trends: miniaturization, standardization and automation. For this reason the mission represents a good test bench scenario to analyze the products of the current small-satellites industry. Once the reference mission has been defined, the preliminary ΔV is computed and the micro-propulsion system is selected. Afterwards, for several satellite subsystems the requirements are compared with the expected performance of a set of small-satellite components currently available on the market. Once the most promising hardware solutions are identified, mass and volume budgets are defined. Subsequently, drawbacks and limits of using COTS components for deep-space exploration are highlighted, focusing on the readiness level of each subsystem. Finally, recommendations are given on what methods and hardware are needed in the near future to overcome the limiting factors and to allow deep-space exploration using low-cost CubeSats
Orbiting low frequency antennas for radio astronomy(OLFAR): Distributing signal processing
Recently, new and interesting science drivers have emerged in the ultra low frequency range of 0.3-30 MHz ranging from the epoch of re-ionization, exo-planets, ultra-high energy cosmic rays and studies of the astronomical dark ages. However at these wavelengths, ground based observations are severely limited due to ionospheric distortions below 50MHz, manmade interference, complete reflection of radio waves below 30MHz and even solar flares (1)
Omics-directed Reverse Genetics Enables the Creation of New Productivity Traits for the Vegetable Oil Crop Canola
Bayer CropScience is a leader in the oilseed rape seeds business with a 2013 market share of 50% in Canada, based on the creation and use of a unique hybridization system enabling the development of high-yielding canola (B.napus) InVigor® hybrids. For the European markets, Bayer is developing non-transgenic hybrids that will be complemented with differentiating traits. To this end, a highly effective mutagenesis-based and omics-directed reverse genetics platform was established which enables the creation of novel productivity traits in canola.The reverse genetics process involves three major steps described in the following figure.The selection of relevant homoeologs is facilitated by Bayer's B.napus genome sequence and transcript atlas. The genome sequence allows the in silico identification of functional homoeologs and the transcript atlas enables to prioritize on homoeologs that are highly expressed in the right tissues. A new trait is created by stacking relevant mutant alleles in a single line. Bayer CropScience is using its canola reverse genetics platform to improve certain canola characteristics including pod shattering, grain yield and oil composition and to develop traits such as herbicide tolerance. Pod shatter reduction was the first trait developed with the platform. A first pod shatter-reduced InVigor hybrid, L140P, was commercially grown in Canada during the 2014 summer season. Bayer CropScience has established and is successfully using a this biotech-based platform for the improvement of the productivity of canola. The resulting traits do not require regulation and can be deployed in all continents. The major limitation of reverse genetics is that the scope of modification is limited to the crops’ own gene content and the expression levels of these genes
Efficacy and safety of a single-dose mebendazole 500 mg chewable, rapidly-disintegrating tablet for Ascaris lumbricoides and Trichuris trichiura infection treatment in pediatric patients : a double-blind, randomized, placebo-controlled, phase 3 study
This randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of a new chewable, rapidly-disintegrating mebendazole (MBZ) 500 mg tablet for Ascaris lumbricoides and Trichuris trichiura infection treatment. Pediatric patients (1-15 years; N = 295; from Ethiopia and Rwanda) excreting A. lumbricoides and/or T. trichiura eggs were enrolled. The study had a screening phase (3 days), a double-blind treatment phase (DBP, 19 days), and an open-label phase (OLP, 7 days). Patients received MBZ or placebo on day 1 of DBP and open-label MBZ on day 19 +/- 2 after stool sample collection. Cure rates (primary endpoint), defined as species-specific egg count of 0 at the end of DBP, were significantly higher in the MBZ group than placebo for A. lumbricoides (83.7% [72/86; 95% CI: 74.2%; 90.8%] versus 11.1% [9/81; 95% CI: 5.2%; 20.1%], P < 0.001) and for T. trichiura (33.9% [42/124; 95% CI: 25.6%; 42.9%] versus 7.6% [9/119; 95% CI: 3.5%; 13.9%], P < 0.001). Egg reduction rates (secondary endpoint) were significantly higher in the MBZ group than placebo for A. lumbricoides (97.9% [95% CI: 94.4; 99.9] versus 19.2% [95% CI: -5.9; 41.5]; P < 0.001) and T. trichiura (59.7% [95% CI: 33.9; 78.8] versus 10.5% [95% CI: -16.8; 32.9]; P = 0.003). Treatment-emergent adverse events (TEAEs) in MBZ group occurred in 6.3% (9/144) of patients during DBP and 2.5% (7/278) during OLP. No deaths, serious TEAEs, or TEAEs leading to discontinuations were reported. A 500 mg chewable MBZ tablet was more efficacious than placebo for the treatment of A. lumbricoides and T. trichiura infections in pediatric patients, and no safety concerns were identified
CMB-S4 Science Book, First Edition
This book lays out the scientific goals to be addressed by the
next-generation ground-based cosmic microwave background experiment, CMB-S4,
envisioned to consist of dedicated telescopes at the South Pole, the high
Chilean Atacama plateau and possibly a northern hemisphere site, all equipped
with new superconducting cameras. CMB-S4 will dramatically advance cosmological
studies by crossing critical thresholds in the search for the B-mode
polarization signature of primordial gravitational waves, in the determination
of the number and masses of the neutrinos, in the search for evidence of new
light relics, in constraining the nature of dark energy, and in testing general
relativity on large scales
Survival-Related Profile, Pathways, and Transcription Factors in Ovarian Cancer
Ate van der Zee and colleagues analyze the gene expression profiles of ovarian cancer samples from 157 patients, and identify an 86-gene expression profile that seems to predict overall survival
CMB-S4: Forecasting Constraints on Primordial Gravitational Waves
CMB-S4---the next-generation ground-based cosmic microwave background (CMB)
experiment---is set to significantly advance the sensitivity of CMB
measurements and enhance our understanding of the origin and evolution of the
Universe, from the highest energies at the dawn of time through the growth of
structure to the present day. Among the science cases pursued with CMB-S4, the
quest for detecting primordial gravitational waves is a central driver of the
experimental design. This work details the development of a forecasting
framework that includes a power-spectrum-based semi-analytic projection tool,
targeted explicitly towards optimizing constraints on the tensor-to-scalar
ratio, , in the presence of Galactic foregrounds and gravitational lensing
of the CMB. This framework is unique in its direct use of information from the
achieved performance of current Stage 2--3 CMB experiments to robustly forecast
the science reach of upcoming CMB-polarization endeavors. The methodology
allows for rapid iteration over experimental configurations and offers a
flexible way to optimize the design of future experiments given a desired
scientific goal. To form a closed-loop process, we couple this semi-analytic
tool with map-based validation studies, which allow for the injection of
additional complexity and verification of our forecasts with several
independent analysis methods. We document multiple rounds of forecasts for
CMB-S4 using this process and the resulting establishment of the current
reference design of the primordial gravitational-wave component of the Stage-4
experiment, optimized to achieve our science goals of detecting primordial
gravitational waves for at greater than , or, in the
absence of a detection, of reaching an upper limit of at CL.Comment: 24 pages, 8 figures, 9 tables, submitted to ApJ. arXiv admin note:
text overlap with arXiv:1907.0447
Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial
Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials.
Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure.
Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen.
Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049
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