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81.
Zusammenfassung Die massive Bedrohung durch Nuklearwaffen, die den Supermächten die Möglichkeit zur Auslöschung allen Lebens auf der Erde geben, erfordert eine Entscheidungsfindung oftmals innerhalb weniger Minuten. Dies hat beide Seiten zum Aufbau von Frühwarn- und Entscheidungssystemen (FWES) veranlaßt, durch deren Einsatz ein atomarer Angriff noch innerhalb der Raketenflugzeit erkannt werden soll. In diesem FWES spielt die Verarbeitung und Weiterleitung von Informationen durch den Computer eine kriegsentscheidende Rolle: Die Informatik ist zu einer der wichtigsten Grundlagenwissenschaften in der Rüstungsforschung geworden. Dieser Artikel gibt eine Übersicht über die Funktionsweise computergestützter FWES und zeigt Fehlerquellen auf, die es möglich und sogar wahrscheinlich machen, daß eine Verkettung unglücklicher Umstände zu einem Nuklearkrieg aus Versehen führen kann.
Liste der Abkürzungen ANMCC Alternate National Military Command Center - BMWES Ballistic Missile Early Warning System - CSS Communication System Segment - EMP Elektromagnetischer Puls - FWES Frühwarn- und Entscheidungssystem - ICBM Intercontinental Ballistic Missile - JCS Joint Chief of Staff - NCS NORAD Computer System - NMCC National Military Command Center - NORAD North American Aerospace Defense Command Center - PAC Pacific Command - PARCS Perimeter Acquisition Radar Attack Characterization System - SAC Strategic Air Command - SCC Space Computational Center - SLBM Submarine-launched Ballistic Missiles - WWMCCS World Wide Military Command and Control System 相似文献
Liste der Abkürzungen ANMCC Alternate National Military Command Center - BMWES Ballistic Missile Early Warning System - CSS Communication System Segment - EMP Elektromagnetischer Puls - FWES Frühwarn- und Entscheidungssystem - ICBM Intercontinental Ballistic Missile - JCS Joint Chief of Staff - NCS NORAD Computer System - NMCC National Military Command Center - NORAD North American Aerospace Defense Command Center - PAC Pacific Command - PARCS Perimeter Acquisition Radar Attack Characterization System - SAC Strategic Air Command - SCC Space Computational Center - SLBM Submarine-launched Ballistic Missiles - WWMCCS World Wide Military Command and Control System 相似文献
82.
Veronique Demers-Mathieu Ciera DaPra Gabrielle Mathijssen David A. Sela Kirsi M. Jrvinen Antti Seppo Shawn Fels Elena Medo 《International journal of molecular sciences》2021,22(4)
Background: Preexisting immunity to SARS-CoV-2 could be related to cross-reactive antibodies to common human-coronaviruses (HCoVs). This study aimed to evaluate whether human milk antibodies against to S1 and S2 subunits SARS-CoV-2 are cross-reactive to S1 and S2 subunits HCoV-OC43 and HCoV-229E in mothers with a confirmed COVID-19 PCR test, in mothers with previous viral symptoms during COVID-19 pandemic, and in unexposed mothers; Methods: The levels of secretory IgA (SIgA)/IgA, secretory IgM (SIgM)/IgM, and IgG specific to S1 and S2 SARS-CoV-2, and reactive to S1 + S2 HCoV-OC43, and HCoV-229E were measured in milk from 7 mothers with a confirmed COVID-19 PCR test, 20 mothers with viral symptoms, and unexposed mothers (6 Ctl1-2018 and 16 Ctl2-2018) using ELISA; Results: The S2 SARS-CoV-2 IgG levels were higher in the COVID-19 PCR (p = 0.014) and viral symptom (p = 0.040) groups than in the Ctl1-2018 group. We detected a higher number of positive correlations between the antigens and secretory antibodies in the COVID-19 PCR group than in the viral symptom and Ctl-2018 groups. S1 + S2 HCoV-OC43-reactive IgG was higher in the COVID-19 group than in the control group (p = 0.002) but did not differ for the other antibodies; Conclusions: Mothers with a confirmed COVID-19 PCR and mothers with previous viral symptoms had preexisting human milk antibodies against S2 subunit SARS-CoV-2. Human milk IgG were more specific to S2 subunit SARS-CoV-2 than other antibodies, whereas SIgA and SIgM were polyreactive and cross-reactive to S1 or S2 subunit SARS-CoV-2. 相似文献
83.
Franziska Dengler Sofia Sova Antti M. Salo Joni M. Mki Peppi Koivunen Johanna Myllyharju 《International journal of molecular sciences》2021,22(8)
The HIF prolyl 4-hydroxylases (HIF-P4H) control hypoxia-inducible factor (HIF), a powerful mechanism regulating cellular adaptation to decreased oxygenation. The gastrointestinal epithelium subsists in “physiological hypoxia” and should therefore have an especially well-designed control over this adaptation. Thus, we assessed the absolute mRNA expression levels of the HIF pathway components, Hif1a, HIF2a, Hif-p4h-1, 2 and 3 and factor inhibiting HIF (Fih1) in murine jejunum, caecum and colon epithelium using droplet digital PCR. We found a higher expression of all these genes towards the distal end of the gastrointestinal tract. We detected mRNA for Hif-p4h-1, 2 and 3 in all parts of the gastrointestinal tract. Hif-p4h-2 had significantly higher expression levels compared to Hif-p4h-1 and 3 in colon and caecum epithelium. To test the roles each HIF-P4H isoform plays in the gut epithelium, we measured the gene expression of classical HIF target genes in Hif-p4h-1−/−, Hif-p4h-2 hypomorph and Hif-p4h-3−/− mice. Only Hif-p4h-2 hypomorphism led to an upregulation of HIF target genes, confirming a predominant role of HIF-P4H-2. However, the abundance of Hif-p4h-1 and 3 expression in the gastrointestinal epithelium implies that these isoforms may have specific functions as well. Thus, the development of selective inhibitors might be useful for diverging therapeutic needs. 相似文献
84.
Ground rubber powder (GRP) and devulcanized rubber (Dev.R) waste through a continuous shear‐flow reaction were used as fillers for virgin natural rubber. A Horikx plot and the gel fraction proved that both main‐chain scission and crosslink scission occurred during the devulcanization. The cure characteristics, swelling behavior, crosslink density, and mechanical properties were studied. GRP and Dev.R, generated from passenger car and light truck tires, showed applicable mechanical properties in the new rubber compounds, and the compounds containing Dev.R demonstrated better properties than those containing GRP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 208–217, 2005 相似文献
85.
Ground rubber powder (GRP) and devulcanized rubber waste obtained using the process of continuous shear flow reaction were used as both fillers and a part of rubber in virgin natural rubber (NR). The cure characteristics, swelling behavior, cross‐link density, mechanical properties, and morphology were studied in our laboratory. The GRP and devulcanized rubber, which were generated from passenger car and light truck tires, showed applicable mechanical properties in new rubber compounds, and the compounds that contained devulcanized rubber showed better properties than those with GRP. In particular, devulcanized rubber as a part of rubber obtained through a cross‐link reaction exhibited excellent mechanical properties, with a strong potential for future applications. POLYM. ENG. SCI., 45:1239–1246, 2005. © 2005 Society of Plastics Engineers 相似文献
86.
Th. Braun M. Wohlers T. Belz G. Nowitzke G. Wortmann Y. Uchida N. Pfänder R. Schlögl 《Catalysis Letters》1997,43(3-4):167-173
The influence of fullerenes and related support materials on the structural and catalytic properties of ruthenium was investigated.
Catalysts based on C60, raw fullerene black, extracted fullerene black, cathode deposit and graphite were prepared by an impregnation/activation
procedure with Ru3CO12. The local co-ordination sphere of the resulting highly dispersed X-ray amorphous ruthenium was investigated by means of
EXAFS. The dominating role of the presence of non-six-membered carbon rings on the structure and the stability of the Ru particles
will be illustrated.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
The specific heat, Cp, was determined by DSC on a series of resol-type phenol formaldehyde resins with varying phenol formaldehyde molar ratio. The extrapolated Cp values at 25°C vary between 1.181-1.206 kJ · kg?1 K?1 and the dCp/dT ratio was found to be 0.0042kJ · kg?1K?2 in the temperature range of 70–125°C. 相似文献
88.
Pekka Manninen Päivi Laakso Heikki Kallio 《Journal of the American Oil Chemists' Society》1995,72(9):1001-1008
This study demonstrates the usefulness of capillary supercritical fluid chromatography (SFC) for the characterization of triacylglycerols
of edible oils and fats. Triacylglycerols were separated according to the acyl carbon number and the degree of unsaturation
on a 25% cyanopropyl/25% phenyl/50% methylpolysiloxane stationary phase. Valuable information concerning the triacylglycerol
composition of berry oils was obtained, despite the overlapping of certain triacylglycerol peaks. Simultaneous analysis of
fat-soluble vitamins and triacylglycerols is not practical by capillary SFC with flame-ionization detection because of the
low concentration of naturally-occurring fat-soluble vitamins in edible oils. Therefore, higher loading of the sample, which
led to overloading of triacylglycerols, was required to get reasonable peaks for fat-soluble vitamins. The method was applied
to the characterization of triacylglycerols and tocopherols in sea buckthorn pulp and seed oil, and cloudberry seed oil without
any sample purification prior to SFC. In addition, the stationary phase proved useful for separating the more complex mixtures
of triacylglycerols found in milk fat and in fish oil. 相似文献
89.
H. Purnama F. Girgsdies T. Ressler J.H. Schattka R.A. Caruso R. Schomäcker R. Schlögl 《Catalysis Letters》2004,94(1-2):61-68
Steam reforming of methanol for production of hydrogen can be carried out over copper based catalyst. In the work presented here, the catalytic properties of a CuO/ZrO2 catalyst (8.5wt%) synthesised by a templating technique were investigated with respect to activity, long term stability, CO formation, and response to oxygen addition to the feed. The results were obtained using a fixed bed reactor and compared to a commercial methanol synthesis catalyst CuO/ZnO/Al2O3. It is shown that, depending on the time on stream, the temporary addition of oxygen to the feed has a beneficial effect on the activity of the CuO/ZrO2 catalyst. After activation, the CuO/ZrO2 catalyst is found to be more active (per copper mass) than the CuO/ZnO/Al2O3 system, more stable during time on stream (measured up to 250h), and to produce less CO. Structural characterisation by means of X-ray powder diffraction (XRD) and X-ray absorption spectroscopy (XAS) reveals that the catalyst (as prepared) consists of crystalline, tetragonal zirconia with small domain sizes (about 60Å) and small/disordered crystallites of CuO. 相似文献
90.
The single NO bond in various ethers derived from 1-hydroxybenzo(d)-1,2,3-triazoles is reduced at mercury cathodes in a 2-electron process giving rise to the non-substituted benzotriazole and a corresponding primary alcohol. Controlled-potential electrolysis actually resulted in isolating the products of the above type eg benzotriazole and 2-piperidinoethanol. Cathodic reduction of non-substituted benzotriazole in acid media proceeds evidently via a chemical reaction between benzotriazole and hydrogen obtained by the catalytic reduction of hydrogen ions at the mercury electrode. 相似文献