62 research outputs found
A three solar cell system based on a self-supporting, transparent AlGaAs top solar cell
Development of a three solar cell stack can lead to practical efficiencies greater than 30 percent (1x,AM0). A theoretical efficiency limitation of 43.7 percent at AM0 and one sun is predicted by this model. Including expected losses, a practical system efficiency of 36.8 percent is anticipated. These calculations are based on a 1.93eV/1.43eV/0.89eV energy band gap combination. AlGaAs/GaAs/GaInAsP materials can be used with a six-terminal wiring configuration. The key issues for multijunction solar cells are the top and middle solar cell performance and the sub-bandgap transparency. AstroPower has developed a technique to fabricate AlGaAs solar cells on rugged, self-supporting, transparent AlGaAs substrates. Top solar cell efficiencies greater than 11 percent AM0 have been achieved. State-of-the-art GaAs or InP devices will be used for the middle solar cell. GaInAsP will be used to fabricate the bottom solar cell. This material is lattice-matched to InP and offers a wide range of bandgaps for optimization of the three solar cell stack. Liquid phase epitaxy is being used to grow the quaternary material. Initial solar cells have shown open-circuit voltages of 462 mV for a bandgap of 0.92eV. Design rules for the multijunction three solar cell stack are discussed. The progress in the development of the self-supporting AlGaAs top solar cell and the GaInAsP bottom solar cell is presented
Mechanically-stacked tandem solar cells with GaAsP on GaP and silicon
Preliminary results are encouraging for the achievement of high conversion efficiencies using a GaAsP top solar cell mechanically stacked on a conventional silicon solar cell. A realistic maximum of 29.4 percent is suggested when both the top and bottom solar cells are state of the art. Practical system efficiencies greater than 25 percent are attainable in the near future with the use of a state of the art bottom solar cell
Serpin Induced Antiviral Activity of Prostaglandin Synthetase-2 against HIV-1 Replication
The serine protease inhibitors (serpins) are anti-inflammatory proteins that have various functions. By screening a diverse panel of viruses, we demonstrate that the serpin antithrombin III (ATIII) has a broad-spectrum anti-viral activity for HIV-1, HCV and HSV. To investigate the mechanism of action in more detail we investigated the HIV-1 inhibition. Using gene-expression arrays we found that multiple host cell signal transduction pathways were activated by ATIII in HIV-1 infected cells but not in uninfected controls. Moreover, the signal pathways initiated by ATIII treatment, were more than 200-fold increased by the use of heparin-activated ATIII. The most up-regulated transcript in HIV-1 infected cells was prostaglandin synthetase-2 (PTGS2). Furthermore, we found that over-expression of PTGS2 reduced levels of HIV-1 replication in human PBMC. These findings suggest a central role for serpins in the host innate anti-viral response. Host factors such as PTGS2 elicited by ATIII treatment could be exploited in the development of novel anti-viral interventions
The lung cancer exercise training study: a randomized trial of aerobic training, resistance training, or both in postsurgical lung cancer patients: rationale and design
<p>Abstract</p> <p>Background</p> <p>The Lung Cancer Exercise Training Study (LUNGEVITY) is a randomized trial to investigate the efficacy of different types of exercise training on cardiorespiratory fitness (VO<sub>2peak</sub>), patient-reported outcomes, and the organ components that govern VO<sub>2peak </sub>in post-operative non-small cell lung cancer (NSCLC) patients.</p> <p>Methods/Design</p> <p>Using a single-center, randomized design, 160 subjects (40 patients/study arm) with histologically confirmed stage I-IIIA NSCLC following curative-intent complete surgical resection at Duke University Medical Center (DUMC) will be potentially eligible for this trial. Following baseline assessments, eligible participants will be randomly assigned to one of four conditions: (1) aerobic training alone, (2) resistance training alone, (3) the combination of aerobic and resistance training, or (4) attention-control (progressive stretching). The ultimate goal for all exercise training groups will be 3 supervised exercise sessions per week an intensity above 70% of the individually determined VO<sub>2peak </sub>for aerobic training and an intensity between 60 and 80% of one-repetition maximum for resistance training, for 30-45 minutes/session. Progressive stretching will be matched to the exercise groups in terms of program length (i.e., 16 weeks), social interaction (participants will receive one-on-one instruction), and duration (30-45 mins/session). The primary study endpoint is VO<sub>2peak</sub>. Secondary endpoints include: patient-reported outcomes (PROs) (e.g., quality of life, fatigue, depression, etc.) and organ components of the oxygen cascade (i.e., pulmonary function, cardiac function, skeletal muscle function). All endpoints will be assessed at baseline and postintervention (16 weeks). Substudies will include genetic studies regarding individual responses to an exercise stimulus, theoretical determinants of exercise adherence, examination of the psychological mediators of the exercise - PRO relationship, and exercise-induced changes in gene expression.</p> <p>Discussion</p> <p>VO<sub>2peak </sub>is becoming increasingly recognized as an outcome of major importance in NSCLC. LUNGEVITY will identify the optimal form of exercise training for NSCLC survivors as well as provide insight into the physiological mechanisms underlying this effect. Overall, this study will contribute to the establishment of clinical exercise therapy rehabilitation guidelines for patients across the entire NSCLC continuum.</p> <p>Trial Registration</p> <p>NCT00018255</p
The First Post-Kepler Brightness Dips of KIC 8462852
We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process
Effects of diet and exercise interventions on diabetes risk factors in adults without diabetes: meta-analyses of controlled trials
BACKGROUND AND AIMS: Fasting insulin (FI), fasting glucose (FG), systolic blood pressure (SBP), high density lipoproteins (HDL), triacylglycerides (TAG), and body mass index (BMI) are well-known risk factors for type 2 diabetes. Reliable estimates of lifestyle intervention effects on these factors allow diabetes risk to be predicted accurately. The present meta-analyses were conducted to quantitatively summarize effects of diet and exercise intervention programs on FI, FG, SBP, HDL, TAG and BMI in adults without diabetes. MATERIALS AND METHODS: MEDLINE and EMBASE were searched to find studies involving diet plus exercise interventions. Studies were required to use adults not diagnosed with type 2 diabetes, involve both dietary and exercise counseling, and include changes in diabetes risk factors as outcome measures. Data from 18, 24, 23, 30, 29 and 29 studies were used for the analyses of FI, FG, SBP, HDL, TAG and BMI, respectively. About 60% of the studies included exclusively overweight or obese adults. Mean age and BMI of participants at baseline were 48 years and 30.1 kg/m(2). Heterogeneity of intervention effects was first estimated using random-effect models and explained further with mixed-effects models. RESULTS: Adults receiving diet and exercise education for approximately one year experienced significant (P <0.001) reductions in FI (-2.56 ± 0.58 mU/L), FG (-0.18 ± 0.04 mmol/L), SBP (-2.77 ± 0.56 mm Hg), TAG (-0.258 ± 0.037 mmol/L) and BMI (-1.61 ± 0.13 kg/m(2)). These risk factor changes were related to a mean calorie intake reduction of 273 kcal/d, a mean total fat intake reduction of 6.3%, and 40 minutes of moderate intensity aerobic exercise four times a week. Lifestyle intervention did not have an impact on HDL. More than 99% of total variability in the intervention effects was due to heterogeneity. Variability in calorie and fat intake restrictions, exercise type and duration, length of the intervention period, and the presence or absence of glucose, insulin, or lipid abnormalities explained 23-63% of the heterogeneity. CONCLUSIONS: Calorie and total fat intake restrictions coupled with moderate intensity aerobic exercises significantly improved diabetes risk factors in healthy normoglycemic adults although normoglycemic adults with glucose, insulin, and lipid abnormalities appear to benefit more
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Proceedings of the 13th annual conference of INEBRIA
CITATION: Watson, R., et al. 2016. Proceedings of the 13th annual conference of INEBRIA. Addiction Science & Clinical Practice, 11:13, doi:10.1186/s13722-016-0062-9.The original publication is available at https://ascpjournal.biomedcentral.comENGLISH SUMMARY : Meeting abstracts.https://ascpjournal.biomedcentral.com/articles/10.1186/s13722-016-0062-9Publisher's versio
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