Laboratory Verification of Electric Double Layer Capacitor Based Power System for a Simple CubeSat Mission

With the coming of CubeSat standard, it has become very attractive venture or endeavor for many universities or schools as an easy approach in conducting research on space related science or education. The nucleus of CubeSat’s mission is the electrical power system which is critical to the spacecraft’s bus and payload. This paper details the testing and sizing of an electric double layer capacitor (EDLC) based CubeSat power system using direct energy transfer topology with utmost consideration for simplicity, ease to handle and durability attributes of EDLC

Development of Electron-emitting Film for Spacecraft Charging Mitigation

Prevention of spacecraft charging and discharging has become increasingly important as geostationary Earth-orbit satellites employ higher bus voltages. There are numerous mitigation techniques against spacecraft charging, including electron emission from the spacecraft chassis. A new electron emission device operating in a completely passive manner has been developed, which uses the field enhancement at the triple junction where the interface of metal and insulator is exposed to space. It has been named electron-emitting film for spacecraft charging mitigation (ELF’S CHARM). Microetching was applied to polyimide-copper laminated film to manufacture a laboratory prototype. This prototype ELF maintains the emission current at the steady state from the triple junctions instead of leading to arcing. The electric field at the triple junction is macroscopically enhanced by charging the polyimide film and microscopically by dielectric impurities on the copper surface. The laboratory experiments confirmed a stable current emission from 10 to 100μA for 4 hr from a 5-mm square sample having a 500-μm microetching pattern. Recently, the endurance of this ELF design has been confirmed by 100 hr of accumulated emission testing

Circulating Mucosal Associated Invariant T Cells Are Activated in Vibrio cholerae O1 Infection and Associated with Lipopolysaccharide Antibody Responses

Background: Mucosal Associated Invariant T (MAIT) cells are innate-like T cells found in abundance in the intestinal mucosa, and are thought to play a role in bridging the innate-adaptive interface. Methods: We measured MAIT cell frequencies and antibody responses in blood from patients presenting with culture-confirmed severe cholera to a hospital in Dhaka, Bangladesh at days 2, 7, 30, and 90 of illness. Results: We found that MAIT (CD3+CD4−CD161hiVα7.2+) cells were maximally activated at day 7 after onset of cholera. In adult patients, MAIT frequencies did not change over time, whereas in child patients, MAITs were significantly decreased at day 7, and this decrease persisted to day 90. Fold changes in MAIT frequency correlated with increases in LPS IgA and IgG, but not LPS IgM nor antibody responses to cholera toxin B subunit. Conclusions: In the acute phase of cholera, MAIT cells are activated, depleted from the periphery, and as part of the innate response against V. cholerae infection, are possibly involved in mechanisms underlying class switching of antibody responses to T cell-independent antigens

Absolute Electron Emission Calibration: Round Robin Tests of Au and Polyimide

Accurate determination of the absolute electron yields of conducting and insulating materials are essential for models of spacecraft charging and related processes involving charge accumulation and emission due to electron beams and plasmas. Apparatus using low-fluence pulsed electron beam sources and various methods to minimize charge accumulation have been developed at facilities around the world. This study presents a round robin comparison of such tests performed in CSIC at Instituto de Ciencia de Materiales de Madrid, LaSeine at Kyushu Institute of Technology, DESSE at ONEREA, and the Space Environment Effects Materials (SEEM) test facility at Utah State University. The primary objectives of the study were to determine the consistency and uncertainties of these absolute yields measurements, and to investigate the effects of the similarities and differences of the diverse facilities. Measurements were made of the absolute total, secondary and backscattered electron yields at normal incidence over the full range of incident energies accessible with each group’s instrumentation (a full range of ~5 eV to ~30 keV). Electron emission spectra at specific incident electron energies were also measured. Measurements were made for identical samples with reproducible sample preparation of two standard materials: (1) the elemental conductor Au (25 μm thick 6N high purity Au foils) and (2) the polymeric insulator polyimide (25 μm thick Kapton HNTM). Studies of the effects on electron yield of Au surface contamination—as measured with Auger Electron Spectroscopy and other techniques—were made for samples: (1) as received, (2) subject to a simple standard cleaning procedure, (3) subsequently baked out under ultrahigh vacuum, and (4) after Ar ion sputter cleaning and thermal annealing. Similarly, studies of the effects of absorbed water and volatile compounds on electron yield were made for polyimide samples: (1) unbaked and (2) subjected to a vacuum bake out. An outline of measurement and analysis techniques used by each laboratory is presented, along with methods used to calibrate the incident energies and absolute yields measured with their different electron detectors. The effects of different charge minimization and neutralization methods are compared. Various empirical and physics-based models to characterize the electron yield curves are used to parameterize the yield data. The values determined at each laboratory for the maximum yield and energy at this yield, the first and second crossover energies, and the asymptotic yield at high energy are also compiled and compared

Corporate boards and performance pricing in private debt contracts

This paper investigates the effects of corporate governance on the use of performance pricing in debt contracts on a sample of newly syndicated loans in the U.S. private debt market. While cross-sectional results provide no evidence for the predicted relation between corporate governance quality and the likelihood of using performance pricing in debt contracts, there is evidence for the predicted positive relation between corporate governance quality and the use of interest-increasing performance pricing provisions. Evidence also provides support for the predicted negative relation between corporate governance quality and the use of financial ratio as the measure of performance underlying the provisions. Overall, empirical evidence supports the hypothesis that debt-holders perceive aspects of corporate governance to be beneficial and factor them in their contracting decisions

Adding 6 months of androgen deprivation therapy to postoperative radiotherapy for prostate cancer: a comparison of short-course versus no androgen deprivation therapy in the RADICALS-HD randomised controlled trial

Background Previous evidence indicates that adjuvant, short-course androgen deprivation therapy (ADT) improves metastasis-free survival when given with primary radiotherapy for intermediate-risk and high-risk localised prostate cancer. However, the value of ADT with postoperative radiotherapy after radical prostatectomy is unclear. Methods RADICALS-HD was an international randomised controlled trial to test the efficacy of ADT used in combination with postoperative radiotherapy for prostate cancer. Key eligibility criteria were indication for radiotherapy after radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to radiotherapy alone (no ADT) or radiotherapy with 6 months of ADT (short-course ADT), using monthly subcutaneous gonadotropin-releasing hormone analogue injections, daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as distant metastasis arising from prostate cancer or death from any cause. Standard survival analysis methods were used, accounting for randomisation stratification factors. The trial had 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 80% to 86% (hazard ratio [HR] 0·67). Analyses followed the intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov, NCT00541047. Findings Between Nov 22, 2007, and June 29, 2015, 1480 patients (median age 66 years [IQR 61–69]) were randomly assigned to receive no ADT (n=737) or short-course ADT (n=743) in addition to postoperative radiotherapy at 121 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 9·0 years (IQR 7·1–10·1), metastasis-free survival events were reported for 268 participants (142 in the no ADT group and 126 in the short-course ADT group; HR 0·886 [95% CI 0·688–1·140], p=0·35). 10-year metastasis-free survival was 79·2% (95% CI 75·4–82·5) in the no ADT group and 80·4% (76·6–83·6) in the short-course ADT group. Toxicity of grade 3 or higher was reported for 121 (17%) of 737 participants in the no ADT group and 100 (14%) of 743 in the short-course ADT group (p=0·15), with no treatment-related deaths. Interpretation Metastatic disease is uncommon following postoperative bed radiotherapy after radical prostatectomy. Adding 6 months of ADT to this radiotherapy did not improve metastasis-free survival compared with no ADT. These findings do not support the use of short-course ADT with postoperative radiotherapy in this patient population

Duration of androgen deprivation therapy with postoperative radiotherapy for prostate cancer: a comparison of long-course versus short-course androgen deprivation therapy in the RADICALS-HD randomised trial

Background Previous evidence supports androgen deprivation therapy (ADT) with primary radiotherapy as initial treatment for intermediate-risk and high-risk localised prostate cancer. However, the use and optimal duration of ADT with postoperative radiotherapy after radical prostatectomy remains uncertain. Methods RADICALS-HD was a randomised controlled trial of ADT duration within the RADICALS protocol. Here, we report on the comparison of short-course versus long-course ADT. Key eligibility criteria were indication for radiotherapy after previous radical prostatectomy for prostate cancer, prostate-specific antigen less than 5 ng/mL, absence of metastatic disease, and written consent. Participants were randomly assigned (1:1) to add 6 months of ADT (short-course ADT) or 24 months of ADT (long-course ADT) to radiotherapy, using subcutaneous gonadotrophin-releasing hormone analogue (monthly in the short-course ADT group and 3-monthly in the long-course ADT group), daily oral bicalutamide monotherapy 150 mg, or monthly subcutaneous degarelix. Randomisation was done centrally through minimisation with a random element, stratified by Gleason score, positive margins, radiotherapy timing, planned radiotherapy schedule, and planned type of ADT, in a computerised system. The allocated treatment was not masked. The primary outcome measure was metastasis-free survival, defined as metastasis arising from prostate cancer or death from any cause. The comparison had more than 80% power with two-sided α of 5% to detect an absolute increase in 10-year metastasis-free survival from 75% to 81% (hazard ratio [HR] 0·72). Standard time-to-event analyses were used. Analyses followed intention-to-treat principle. The trial is registered with the ISRCTN registry, ISRCTN40814031, and ClinicalTrials.gov , NCT00541047 . Findings Between Jan 30, 2008, and July 7, 2015, 1523 patients (median age 65 years, IQR 60–69) were randomly assigned to receive short-course ADT (n=761) or long-course ADT (n=762) in addition to postoperative radiotherapy at 138 centres in Canada, Denmark, Ireland, and the UK. With a median follow-up of 8·9 years (7·0–10·0), 313 metastasis-free survival events were reported overall (174 in the short-course ADT group and 139 in the long-course ADT group; HR 0·773 [95% CI 0·612–0·975]; p=0·029). 10-year metastasis-free survival was 71·9% (95% CI 67·6–75·7) in the short-course ADT group and 78·1% (74·2–81·5) in the long-course ADT group. Toxicity of grade 3 or higher was reported for 105 (14%) of 753 participants in the short-course ADT group and 142 (19%) of 757 participants in the long-course ADT group (p=0·025), with no treatment-related deaths. Interpretation Compared with adding 6 months of ADT, adding 24 months of ADT improved metastasis-free survival in people receiving postoperative radiotherapy. For individuals who can accept the additional duration of adverse effects, long-course ADT should be offered with postoperative radiotherapy. Funding Cancer Research UK, UK Research and Innovation (formerly Medical Research Council), and Canadian Cancer Society

Amylatic Activity of Agaricus and Moulds for the Production of Bioethanol

Fermentation of potato and carambola juice was investigated using Molds and Agaricus as a potential source of amylase. The amylatic activity of Moulds and Agaricus were studied and the effects of different parameters, such as starch concentrations, pH, incubation time, temperature were investigated. The maximum enzyme activity obtained for Moulds were 173 to 178U/g under the optimum conditions of an incubation period of 30min, 1.5 % starch solution, an incubation temperature of 60°C and a pH of 5.0. For Agaricus, the highest amylase production was 14 to 16U/g using 1.5 % starch solution, pH of 6.0 incubated at 75°C for 30 minutes. Reducing sugar was produced by fermentation of potato and carambola juice using mold and saccarification was conducted for production of bioethanol using yeasts. The ethanol produced from potato and carambola was approximately 11% (v/w) and 5% (v/v) respectively