3,950 research outputs found
Solar Cooker Project of ADES
The article describes the contribution of the ADES (Association pour le Développement de l’Énergie Solaire Suisse - Madagascar) Solar Cooker Project in the south of Madagascar: fighting the ongoing deforestation, preserving the environment and fighting poverty. It explains advantages and disadvantages of solar cooking and the challenges to change traditional cooking habits. It shows the achievements of the project after five years of existence and the future goals and long term perspectives of ADES in the field of cooking methods and in the field of electricity in rural areas by using renewable energies
Planetary/DOD entry technology flight experiments. Volume 3: Planetary entry flight experiments handbook
The environments produced by entry into Jupiter and Saturn atmospheres are summarized. Worst case design environments are identified and the effect of entry angle, type of atmosphere and ballistic coefficient variations are presented. The range of environments experienced during earth entry is parametrically described as a function of initial entry conditions. The sensitivity of these environments to vehicle ballistic coefficient and nose radius is also shown. An elliptical deorbit maneuver strategy is defined in terms of the velocity increment required versus initial entry conditions and apoapsis altitude. Mission time, ground track, and out of plane velocity penalties are also presented. Performance capabilities of typical shuttle launched boosters are described including the initial entry conditions attainable as a function of paylaod mass and apoapsis altitude
Planetary/DOD entry technology flight experiments. Volume 4: DOD entry flight experiments
For abstract, see vol. 1
Planetary/DOD entry technology flight experiments. Volume 1: Executive summary
The feasibility of using the space shuttle to launch planetary and DoD entry flight experiments was examined. The results of the program are presented in two parts: (1) simulating outer planet environments during an earth entry test, the prediction of Jovian and earth radiative heating dominated environments, mission strategy, booster performance and entry vehicle design, and (2) the DoD entry test needs for the 1980's, the use of the space shuttle to meet these DoD test needs, modifications of test procedures as pertaining to the space shuttle, modifications to the space shuttle to accommodate DoD test missions and the unique capabilities of the space shuttle. The major findings of this program are summarized
Normal values of blood pressure self-measurement in view of the 1999 World Health Organization-International Society of Hypertension guidelines
New guidelines for the management of hypertension have been published in 1999 by the World Health Organization (WHO) and the International Society of Hypertension (ISH). The WHO/ISH Committee has adopted in principle the definition and classification of hypertension provided by the JNC VI (1997). The new classification defines a blood pressure of 120/80 mm Hg as optimal and of 130/85 mm Hg as the limit between normal and high-normal blood pressure. It is unclear which self-measured home blood pressure values correspond to these office blood pressure limits. In this study we reevaluated data from our Dübendorf study to determine self-measured blood pressure values corresponding to optimal and normal office blood pressure using the percentiles of the (office and home) blood pressure distributions of 503 individuals (age, 20 to 90 years; mean age, 46.5 years; 265 men, 238 women). Self-measured blood pressure values corresponding to office values of 130/85 mm Hg and 120/80 mm Hg were 124.1/79.9 mm Hg and 114.3/75.1 mm Hg. Thus, we propose 125/80 mm Hg as a home blood pressure corresponding to an office blood pressure of 130/85 mm Hg (WHO 1999: normal) and 115/75 mm Hg corresponding to 120/80 mm Hg (optimal). Am J Hypertens 2000;13:940-943 © 2000 American Journal of Hypertension, Lt
Validation of preoperative variables and stratification of patients to help predict benefit of cytoreductive nephrectomy in the targeted therapy ERA
Kinetic and Structural Analysis of the Mg2+ -binding Site of the Guanine Nucleotide-binding Protein p21 H-ras.
The coordination and binding of the Mg2+ ion in the nucleotide−binding site of p21 have been investigated using site−directed mutagenesis, kinetic methods, and phosphorous NMR. Mg2+ in the p21.nucleotide.Mg2+ complex appears to be in fast equilibrium with the solvent. The dissociation constant between Mg2+ and the p21.GDP complex was determined to be 2.8 microM. It decreases 30− or 16−fold on substituting Ser−17 or Asp−57 with alanine, respectively, whereas the T35A mutation has no effect. All three mutations influence the dissociation constants and the association and dissociation rate constants of the interaction between guanine nucleotides and p21, but to a different degree. We conclude that Thr−35 is only complexed to Mg2+ in the GTP conformation and both Asp−57 and Ser−17 appear to be critical for both GDP and GTP binding. 31P NMR spectra of the GDP and Gpp(NH)p (guanosine−5'−(beta,gamma−imido)triphosphate) complexes of mutated p21 show a remarkable perturbation of the guanine nucleotide− binding site compared to wild−type protein. The mutant proteins show reduced GTPase rates, which are not stimulated by the GTPase−activating protein GAP. p21(S17A) has been reported to function just as p21(S17N) as a dominant negative inhibitor of normal p21. We find that it inhibits oncogenic p21−induced survival of primary neuron
Experimenting from a distance in case of diffraction and interference
Diffraction and interference are basic phenomena of waves. They are treated in wave optics extensively, because experimental setups are easy to built, diffraction patterns are visible and because of their importance for further
subjects at school and university (diffraction of X-rays, cristallography, Fourier-Transformation, . . . ). Unfortunately, in many cases the experiments are demonstration experiments with a few diffracting objects and not enough possibilities for the students to participate. Therefore we developed a very flexible Remotely Controlled Laboratory (RCL) about diffraction and interference—a real experiment, which can be performed over the internet. The user can choose from among 5 different wavelengths, about 150 diffracting objects and 3 different techniques of qualitative and quantitative measurement. In this contribution we describe the experimental setup, give an overview about experimental results and end with the added value of the experiment
Assessment of bladder pressure and discomfort symptoms: How do overactive bladder differ from interstitial cystitis/bladder pain syndrome patients?
BACKGROUND: To better understand the sensation of bladder pressure and discomfort , and how they are similar or distinct from the pain and urgency symptoms in IC/BPS and OAB.
METHODS: IC/BPS and OAB patients rated their bladder pain, pressure, discomfort, and urinary urgency on separate 0-10 numeric rating scales (NRS). Their NRS ratings were compared between IC/BPS and OAB, and Pearson correlations were performed.
RESULTS: Among IC/BPS patients (n = 27), their mean numeric ratings of pain, pressure, discomfort, and urinary urgency were almost identical (6.6 ± 2.1, 6.0 ± 2.5, 6.5 ± 2.2, and 6.0 ± 2.8 respectively). The three-way correlations between pain, pressure, or discomfort were very strong (all \u3e 0.77). Among OAB patients (n = 51), their mean numeric ratings of pain, pressure, and discomfort (2.0 ± 2.6, 3.4 ± 2.9, 3.4 ± 2.9) were significantly lower than urgency (6.1 ± 2.6, p \u3c 0.001). The correlations between urgency and pain, and between urgency and pressure were weak in OAB (0.21 and 0.26). The correlation between urgency and discomfort was moderate in OAB (0.45). The most bothersome symptom of IC/BPS was bladder/pubic pain, while the most bothersome symptom of OAB was urinary urgency and daytime frequency.
CONCLUSIONS: IC/BPS patients interpreted bladder pain, pressure, or discomfort as the similar concepts and rated their intensity similarly. It is unclear whether pressure or discomfort provide additional information beyond pain in IC/BPS. Discomfort may also be confused with urgency in OAB. We should re-examine the descriptors pressure or discomfort in the IC/BPS case definition
Energy-efficiency improvements for optical access
This article discusses novel approaches to improve energy efficiency of different optical access technologies, including time division multiplexing passive optical network (TDM-PON), time and wavelength division multiplexing PON (TWDM-PON), point-to-point (PTP) access network, wavelength division multiplexing PON (WDM-PON), and orthogonal frequency division multiple access PON (OFDMA-PON). These approaches include cyclic sleep mode, energy-efficient bit interleaving protocol, power reduction at component level, or frequency band selection. Depending on the target optical access technology, one or a combination of different approaches can be applied
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