3,490 research outputs found

    STS Science and Applications Payloads: An Evolving Perspective

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    NASA is now in the early operational phase of the Shuttle Program. The STS-5 mission has, for the first time, conducted reimbursable commercial satellite deployments, while STS-6, -7, -8, and -9 continue the process of settling into an operational mode. With the onset of this phase of Shuttle operations, it is appropriate to reexamine the structure of the NASA R&D STS payload program. Throughout the years from 1975 to 1981, program office attention has been focused on the first few R&D payloads, notably the OSTA-1 payload which contained a collection of Earth resources-oriented experiments, flying on the second Shuttle flight; the OSS-1 payload which examined the immediate Shuttle electromagnetic, gas, and particulate environment; and the Spacelab 1 and 2 missions whose primary purpose is the engineering verification of the Spacelab system, while, at the same time, obtaining significant scientific data

    Capturing the Dynamic Nature of Cyber Risk: Evidence from an Explorative Case Study

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    In this research, we developed a novel approach to enable a dynamic cyber risk management strategy as the dynamic nature of cyber risk is rarely considered in current decision support tools. Our explorative case study shows that many management challenges such as investment decisions, priority setting, and “shelf time” analyses can be continuously analyzed. Our research using system thinking and modelling provides valuable insights about these challenges to support current strategic decision-making practices and improve managerial learning. These insights enable management to identify and analyze the effectiveness of future cyber risk management strategies before implementing them

    De tussenregeling voor valutaresultaten op deelnemingen

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    Met terugwerkende kracht tot 8 april 2011 is een wetsvoorstel ingediend om valutaresultaten op deelnemingen te doen belasten bij belastingplichtigen die in hun aangifte vennootschapsbelasting op grond van het Deutsche Shell-arrest een aftrek van valutaverliezen op deelnemingen claimen: de tussenregeling voor valutaresultaten op deelnemingen. De auteurs gaan in deze bijdrage in op de details van deze tussenregeling en onderzoeken daarbij tevens of het risico dat het Hof van Justitie EU de Deutsche Shell-doctrine ook toe gaat passen op deelnemingen, reëel is. Ook wordt de Europeesrechtelijke houdbaarheid van de tussenregeling zelf getoetst. Om de overkill van de tussenregeling weg te nemen, worden tot slot enige verbetervoorstellen gedaan

    Delayed wound repair in sepsis is associated with reduced local pro-inflammatory cytokine expression

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    Sepsis is one of the main causes for morbidity and mortality in hospitalized patients. Moreover, sepsis associated complications involving impaired wound healing are common. Septic patients often require surgical interventions that in-turn may lead to further complications caused by impaired wound healing. We established a mouse model to the study delayed wound healing during sepsis distant to the septic focus point. For this reason cecal ligation and puncture (CLP) was combined with the creation of a superficial wound on the mouse ear. Control animals received the same procedure without CPL. Epithelialization was measured every second day by direct microscopic visualization up to complete closure of the wound. As interplay of TNF-α, TGF-ÎČ, matrix metalloproteinases (MMP), and tissue inhibitors of metalloproteinases (TIMP) is important in wound healing in general, TNF-α, TGF-ÎČ, MMP7, and TIMP1 were assessed immunohistochemical in samples of wounded ears harvested on days 2, 6, 10 and 16 after wounding. After induction of sepsis, animals showed a significant delay in wound epithelialization from day 2 to 12 compared to control animals. Complete wound healing was attained after mean 12.2± standard deviation (SD) 3.0 days in septic animals compared to 8.7± SD 1.7 days in the control group. Septic animals showed a significant reduction in local pro-inflammatory cytokine level of TNF-α on day 2 and day 6 as well as a reduced expression of TGF-ÎČ on day 2 in wounds. A significant lower expression of MMP7 as well as TIMP1 was also observed on day 2 after wounding. The induction of sepsis impairs wound healing distant to the septic focus point. We could demonstrate that expression of important cytokines for wound repair is deregulated after induction of sepsis. Thus restoring normal cytokine response locally in wounds could be a good strategy to enhance wound repair in sepsis

    Effect of Solution pH on the Dual Role of Dissolved Organic Matter in Sensitized Pollutant Photooxidation

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    [Image: see text] Dissolved organic matter (DOM) has a dual role in indirect phototransformations of aquatic contaminants by acting both as a photosensitizer and an inhibitor. Herein, the pH dependence of the inhibitory effect of DOM and the underlying mechanisms were studied in more than 400 kinetic irradiation experiments over the pH range of 6–11. Experiments employed various combinations of one of three DOM isolates, one of two model photosensitizers, the model antioxidant phenol, and one of nine target compounds (TCs), comprising several aromatic amines, in particular anilines and sulfonamides, and 4-cyanophenol. Using model photosensitizers without antioxidants, the phototransformation of most TCs increased with increasing pH, even for TCs for which pH did not affect speciation. This trend was attributed to pH-dependent formation yields of TC-derived radicals and their re-formation to the parent TC. Analogous trends were observed with DOM as a photosensitizer. Comparison of model and DOM photosensitizer data sets showed increasing inhibitory effects of DOM on TC phototransformation kinetics with increasing pH. In systems with anilines as a TC and phenol as a model antioxidant, pH trends of the inhibitory effect could be rationalized based on the reduction potential difference (ΔE(red)) of phenoxyl/phenol and anilinyl/aniline couples. Our results indicate that the light-induced transformation of aromatic amines in the aquatic environment is governed by the pH-dependent inhibitory effects of antioxidant phenolic moieties of DOM and pH-dependent processes related to the formation of amine oxidation intermediates

    Differences in the performance tests of the fast and slow stretch and shortening cycle among professional, amateur and elite youth soccer players

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    The purpose of this study was to establish whether physical attributes can differentiate between professional, amateur and elite youth soccer players; such a distinction could aid in the selection process for youth soccer. Therefore, this investigation evaluated a suspected difference in the performance tests of the slow and fast stretch and the shortening cycle (squat jump [SJ], countermovement jump [CMJ], and drop jump from varying heights [DJ]) among professional, amateur and elite youth soccer players. Cross-sectional data were collected. The results indicate that higher performance in the SJ and CMJ seem to depend on the level of player because the mean performance of the PRO was 38.7 ± 4.0 cm in the SJ and 41.2 ± 3.8 in the CMJ, which were significantly (p<0.05) different compared with all other groups. In the DJ, there were significant (p<0.05) differences between the professional players (PRO) and lower-level players as well as between the PRO and youth soccer players. The results suggest that jump performance can differentiate between elite, sub-elite, and youth soccer players and highlights the importance of appropriate conditioning for developing strength and power in youth soccer players
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