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Es wird ein Uberblick uber die Intensivbehandlung des Schadelhirn-traumas gegeben. Verletzungen des Zentralnervensystems fuhren zu zahlreichen Storungen, die u.a. sich auf das Herz-Kreislauf-System, die Atmung, die Temperatur, Stoffwechselprozesse und endokrine Leistungen auswirken. Dementsprechend fallen umfangreiche Uberwachungsaufgaben an. Die Behandlung hat die Minderung der intrakraniellen Drucksteigerung, die Stabilisierung der Hirndurchblutung, die ausreichende Sauerstoffversorgung der geschadigten Hirnzelle und die Bilanzierung des Stoffwechsels zu berucksichtigen.

Summary The survival of dried preparations of T1 coliphage was studied in flight experiments on board high altitude balloons, rockets and satellites in the stratosphere and near-earth space environment (34–460 km). Complete inactivation of phage particles was observed. The solar UV-radiation was the major inactivating factor. Laboratory experiments with light sources of various wavelengths, and a flight experiment with optical filters on board a high altitude sounding rocket showed that radiation of the spectral range between 200 and 300 nm was mainly responsible for the inactivation of the phage particles. Shorter Avavelengths were effective only when the phage particles were exposed to the radiation in a relatively unprotected way. Suitable phage preparations were obtained by culturing the E. coli B host cells either in beef extract, or in a synthetic medium. Under the experimental conditions, no other component of the space environment apart from the UV-radiation showed a lethal effect on the dried coliphage.

A review is presented of the optical measurement techniques as they have been applied to the characterization of III–V compounds and alloys. The methods discussed and the more detailed examples cited are: absorption (AIP, Ga1−xAlxP), reflectance, cathodoluminescence (Ga1−xAlxAs), photoluminescence (GaAs1−yPy), electroluminescence (time-decay of Ga1−xAlxAs EL), and automated photoluminescence materials screening (GaAs1−yPy).

Over a 6-year period, a colony of Saimiri was established for experimental behavioral research. Heterosexual pair housing prevailed, and a number of offspring was produced. Females apparently underwent a lengthy adjustment process, inasmuch as viable infant production was infrequent until the female had been paired for three breeding seasons. Males required only a short period of adjustment, if any, to become effective breeders. Breeding was seasonal and births occurred during the summer. The mean maximum gestation for five females who delivered in one year was 162.6 days (range 152-168 days, n = 5). The short gestations for some of these females relative to those previously reported by other investigators suggest a broad range of variability in gestation for this species. The possibility that some of these five females conceived very soon after being paired with males is discussed with regard to social and coital influences on ovulation.

The indirect energy gap ${E}_{g}$ of GaP in the temperature range from 0 to 900\ifmmode^\circ\else\textdegree\fi{}K was determined from absorption measurements. Below 400\ifmmode^\circ\else\textdegree\fi{}K, ${E}_{g}$ was determined from absorption due to the creation of excitons at isolated nitrogen atoms substituted on P sites. This absorption was measured with wavelength-modulated exciting light. The intrinsic absorption edge was measured over the full temperature range by conventional transmission. Above 400\ifmmode^\circ\else\textdegree\fi{}K, the gap was determined from a numerical fit of the intrinsic-edge absorption data to a theoretical expression using parameters obtained from low-temperature measurements, with ${E}_{g}$ as the only adjustable parameter. The shapes of the experimental curves are in good agreement with the theoretical calculations. At 300\ifmmode^\circ\else\textdegree\fi{}K, ${E}_{g}$ is 2.261 eV. Light emission from diodes was studied from 300 to 900\ifmmode^\circ\else\textdegree\fi{}K. The principal high-temperature emission line parallels the energy gap at about 45-meV lower energy, and is attributed to an exciton recombination.

A vapor arc light source has been adapted to the study of the lethal action on bacteria of near-ultraviolet (UV) and visible light. Its use makes possible much shorter exposure times than could be obtained from previously available sources. The output of radiant energy is sufficient to provide a fairly detailed action spectrum for lethality in the long-UV and visible region without the addition of exogenous sensitizers. Populations of cells of Escherichia coli WP2 were inactivated through five log 10 cycles with light at 460 nm. Significant inactivation also was obtained with light at 550 and 650 nm.

— The spectral features and related parameters of the ground state structure of 1,3,6′,8′-tetramethyldehydrodianthrone (TMD) which, according to the theoretical approach used in this paper, is identical with dehydrodianthrone, have been calculated with the aid of the Pariser-Pam-Pople semiempirical SCF LCAO MO method with CI. The calculated singlet-singlet absorption spectra and triplet-triplet absorption spectra are in very good agreement with previous experimental findings. The object of the present paper, however, is to theoretically establish the nature of the green photochromic species of TMD. Calculations have been made for several plausible structures for this species which have been proposed earlier. The results suggest that the valence-isomeric form V is the most probable structure of the green photochromic form of the dehydrodianthrone and its derivatives.

A conductance cell assembly is reported of the capillary design with a cell constant sufficiently high to permit precise electrical conductance measurements with the standard type precision conductance bridge circuits. Important features are the use of single crystal grade MgO for construction of the capillaries that determine the resistance for the electrolyte in the conductance cell, and the use of such materials as gold, or gold‐palladium alloy to construct the various other components of the cell that contact the molten salts. The suspension of the MgO crystal capillaries is of a novel design which permits removal of the capillaries from the assembly for inspection or cleaning, and yet holds these firmly and securely in position during measurements. It is shown that recently published values of electrical conductance for molten KCl and KNO3 may be used as standards for calibration of such cells at high temperatures.

Measurement and analysis of indirect interband optical absorption in GaP. Deviations from a simple indirect absorption law are shown to be consistent with those given by a model which takes into account both the variation of the energy denominators with photon energy and indirect absorption to higher-energy conduction-band valleys. The analysis of the GaP data indicates that such an analysis on data of limited absorption-constant range can provide reasonably accurate values of the direct band gap. The value of the direct band gap best fitting this model for AlAs at 6 K is 3.13 eV. In GaP and AlAs there is evidence of a higher set of extrema giving rise to an additional indirect absorption component 0.34 and 0.20 eV, respectively, above that due to the lowest-energy conduction-band minima. The strength of the absorption due to these higher-energy valleys indicates that they contain states of X sub 3 symmetry.

The technique of epitaxial growth from solution has been applied to GaP. Single‐crystalline overgrowths up to 80 μ thick on (111)‐oriented substrate crystals were obtained by the slow cooling of GaP‐saturated Ga solutions. n‐type overgrowths (Te‐doped) on p‐type substrates (Zn, O‐double doped) gave planar p—n junctions free of gross defects. The I—V characteristics of these diodes show an exponential behavior of the form I=I0 exp (eV/βkT). Values for β were mostly between 1.5 and 1.8 at 300°K. At low currents, the I—V characteristics are interpreted by tunneling. The junctions emitted red light at 300°K in a broad band with the peak at about 1.77 eV (7000 A). The emission intensity varies with I2 at low currents, changes to a linear dependence at intermediate currents, and is sublinear at high currents. The external differential quantum efficiency was measured to be as high as 7.5×10−3. The temperature dependence of the emission intensity and the efficiency were measured and are discussed.

Electroluminescence can occur as a result of the application of a direct current at a low voltage to a suitably doped crystal containing a p-n junction. It has become apparent in recent years that in certain materials (such as gallium arsenide) and under certain conditions, the efficiency of conversion of electric energy into light can be remarkably high. Since these semiconductor light sources operate at low voltages and low currents and can be made very small, they appear attractive for use in small optical displays. Because they can be switched very rapidly and have fairly monochromatic emission properties, their applications for data transmission are also promising.

Unter Berucksichtigung experimenteller und klinischer Mitteilungen und eigener Beobachtungen zum Problemkreis der Wiederbelebung wird zur Frage des zentralen Todes Stellung genommen. Um eine bessere Vergleichbarkeit der Ergebnisse zu erhalten, sind die Untersuchungen der Patienten in lebensbedrohten Zustanden mit gleichartigen Methoden nach genormten Kriterien erforderlich; nur so lassen sich die vielen widerspruchlichen Angaben losen. Neurologische, psychische, vegetative und neurophysiologische Parameter sind zur Bestimmung der Funktion des ZNS gleicherma\en erforderlich. Bei volliger Areagibilitat des ZNS und Ableitung eines Null-Linien-EEG uber 24 Stunden ist nach bisherigen Erkenntnissen die Annahme des zentralen Todes gerechtfertigt. Die Prognose nach Wiederbelebung ist um so ungunstiger, je gro\er die Erholungslatenz ist. Durch Ableitung kortikaler Bestandspotentiale und die Bestimmung der zerebralen arteriovenosen O2-Differenz kann eine weitere Einengung der Diagnose des zentralen Todes erwartet werden, angiographische Untersuchungen werden nur bei erhohtem Hirndruck Entscheidungshilfen sein konnen.

Bei der Umsetzung von (CF3S)2NH mit CF3SNCO bzw. werden nicht, wie erwartet, die entsprechenden Harnstoffe erhalten, sondern quantitativ (CF3S)3N und Cyanursaure. Sowohl (CF3S)2NH als auch (CF3S)3N reagieren mit SCl2 und liefern CF3SCl, S4N3Cl und S2Cl2. Im Falle des Imids entsteht zusatzlich noch HCl. Ahnlich verlauft die Reaktion mit Benzoylchlorid; unter Eliminierung von CF3SCl bildet sich das CF3S · NH · · C6H5, das auch aus CF3SCl und Benzamid hergestellt worden ist. Lediglich die Umsetzungen des Imids mit Cl3−nFnCSCl (n = 0, 1, 2) fuhrte partiell zu einer Kondensation unter HCl-Austritt. Hierbei entstanden in Anwesenheit von Trimethylamin (CF3S)2NSCFnCl3−n (n = 0, 1, 2) und CF3SN(SCFnCl3-n)2 (n = 1, 2). Fur die neu hergestellten Verbindungen werden IR-, 19F-NMR und Massenspektren angegeben. Reaktionsmechanismen werden diskutiert. Reactions of (CF3S)2NH with CF3SNCO and , respectively, did not give the corresponding urea derivatives but quantitatively (CF3S)3N and cyanuric acid. SCl2 reacts with (CF3S)2NH as well as with (CF3S)3N to form CF3SCl, S4N3Cl and S2Cl2. In addition, the imide produces also HCl. Benzoylchloride reacts similarly under elimination of CF3SCl to the compound , which could also be obtained from benzamide and CF3SCl. Condensation reactions were only observed with Cl3–nFnCSCl (n = 0, 1, 2) and the imide. In the presence of trimethylamine the substances (CF3S)2NSCFnCl3–n (n = 0, 1, 2) and CF3SN(SCCl3–nFn)2 (n = 1, 2) were formed. IR and 19F-n.m.r. data as well as massspectra are presented; reaction mechanisms are discussed.

1. Es wurde optisch leeres Silberchlorid und Silberbromid in Kristallen aus dem Schmelzflusse hergestellt.

Dried suspensions ofPenicillium roqueforti Thom, Coliphage T-1,Bacillus subtilis and tobacco mosaic virus were exposed to space on board the Gemini-IX-A and XII earth satellites and the Agena-VIII space rocket. All micro-organisms tested survived the direct exposure during the Gemini-IX-A experiment. In the Gemini-XII experiment only the T-1 phage survived the direct exposure. The survival was influenced by the suspending medium and depended on the species of the microorganism. After four months of space flight on the Agena-VIII space rocket surviving fractions between 2×10−3 and 1.0 were found in the unopened flight container. However, micro-organisms exposed on the cover of the container during this period were completely inactivated. Shielding against solar ultraviolet radiation during flight resulted in survival of micro-organisms exceeding to that of the transport controls, and the survival was considered complete. Sterile methylcellulose collection surfaces were exposed to space on board the Gemini-IX-A and XII satellites in an attempt to collect viable micro-organisms in space. None of the collection surfaces yielded viable micro-organisms.

Five 30-lb, 4-in.-diam iodide hafnium ingots representing material typical cf that utilized for the Shippingport PWR were fabricated into strip. Typical tensile, impact, hardness, corrosion test weight gain, electrical resistivity, and chemical analysis values were obtained by testing samples from each strip. The effect of irradation on the impact strengih and hardness of hafnium strip was investigated by subjecting a total of 36 subsized Izod impact specimens to irradiation for two cycles in the MTR. A duplicate group of nonirradiated specimens was used as a control group. The mechanical, physical, and corrcsion property measurements for the nonirradiated and irradiated samples showed no physically significant differences attributable to chemical analysis. The impact strength and hardness values for the irradiated specimens showed differences which were attributable to the integrated neutron flux received. (auth)

1. Es wurden die Gleichgewichte zwischen Thallium und Blei mit Thallium (1) chlorid und Bleichlorid irn Schmelzflus untersucht.

A method for the precise measurement of surface tension and density of molten salts in one apparatus at temperatures up to 1000°C is reported. The essential features of the apparatus are a density bob of special design to enable surface tension data to be obtained simultaneously, and a continuously variable height crucible arrangement for the liquid sample. A description of the apparatus and the calibration procedures are given in detail. The results for molten potassium nitrate up to 470°C are reported to illustrate the method.

The electroluminescence from GaP containing Ge has been studied. p—n junctions were formed by the liquid epitaxy method. The peak of the dominant emission from these diodes is near 1.96 eV at 77°K. The maximum external quantum efficiency at 77°K was 8%. The emission appears to involve Zn and Ge pairs even though these impurities were doped on opposite sides of the junction. It was not possible to ascribe any emission lines to recombination involving Te and Ge. Current, voltage, and intensity dependences of the diodes have been measured. The results indicate that radiative recombination between Zn and Ge at 77°K is predominantly in the space‐charge region. At low currents, photon‐assisting tunneling becomes important.

Die Atmungsgeschwindigkeit einer obergärigen Backhefe wurde elektrochemisch nach Zusatz verschiedener Zuckerarten gemessen. Hierbei mußte zunächst die Hauptmenge der in der Hefe von der Fabrikation her vorhandenen Nährstoffe durch Veratmung bis auf eine etwa 1/10 der Normalatmung betragende Restatmung entfernt werden. Ein Zusatz verschiedener Zuckerarten beschleunigt die Atmungsgeschwindigkeit bei gleichen Zusätzen in sehr unterschiedlichem Ausmaß. Auch die Gesamtmenge an veratmetem Zucker bis zum Erreichen der geringen Restatmung zeigte bei den verschiedenen Zuckerarten sehr große Differenzen. Bei Saccharose, Maltose und Raffinose wurden nach dem Zusatz Anlaufzeiten bis zur Erreichung der verstärkten Atmung zwischen 4 und 11 Min. festgestellt, verursacht durch die verschieden lange Dauer der fermentativen Zerlegung in die Monosaccharide.

Thorium-protactinium alloys were prepared in small quantities by the Van Arkel process, starting from mixed thorium-protactinium carbides. The wire specimens thus obtained were used directly for structure determination by the Debye-Scherrer method. The lattice parameter of the alpha-phase of thorium diminishes according to a linear function with increasing protactinium content, according to Vegard's law. The solubility of protactinium in alpha thorium is 6.7 ± 0.3% at 1300 ± 30 dgC, and 4.5 ± 0.5% at room temperature. At higher protactinium concentrations a second phase precipitated; this was identified as having an analogous structure to body-centred tetragonal protactinium with slightly increased lattice parameters: α0 = 3.938 ± 0.002, and c 0 = 3.245 ± 0.002 A . The parameter increase is attributed to its saturation with thorium.

Electroluminescence from semiconductor diode light sources can occur as a result of the application of a direct current at a low voltage to a suitably doped crystal containing a p-n junction. In recent years, it has become apparent that in some materials the efficiency of conversion of electric energy to visible light can be appreciably high. Since light-emitting diodes are compatible with the present electronic circuitry, they have many potential applications.

GaP, both undoped and Se‐ or S‐doped, has been vapor deposited onto the polar 111A (Ga face) and 111B (P or As face) surfaces of GaAs and GaP substrates by means of a PCl3 chemical‐transport method. Hall measurements carried out on the crystals over the temperature range of 77°–500°K and optical spectra taken on as‐grown and zinc‐diffused samples show a pronounced substrate orientation and substrate material effect. Samples grown on GaAs substrates are less uniform than those grown on GaP, and show both a carrier concentration gradient and arsenic contamination. Samples grown on GaP substrates have given electron mobilities as high as 187 cm2/V·sec at room temperature going to 2130 cm2/V·sec at liquidnitrogen temperature. The residual impurity in undoped crystals grown on 111B substrates is shown to be sulfur at a concentration of 2−3×1016 cm−3. Undoped crystals grown on 111A substrates are high‐resistivity p type. Both optical studies and electrical measurements show compensation in the n‐type crystals to be of the order of 10%.

Das Auftreten von Komplikationen nach Durchfuhrung vonTorkildsen-Drainagen wird bestimmt durch das Verfahren selbst, den gesteigerten intrakraniellen Druck und das Grundleiden. Haufigste Komplikationen waren bei Durchsicht eines Krankengutes von 142 Ventrikulozyster-nostomien Liquorfisteln und Entlastungsfolgen. Eine weitere Reduktion der im einzelnen dargestellten Komplikationen last sich durch stufenweise und allmahliche Senkung des intrakraniellen Druckes vor dem eigentlichen Eingriff und Anwendung des vonTonnis empfohlenen Wechselschnittes erreichen. Damit konnen die so gunstigen Uberlebenschancen beim Verschlushydrozephalus gebessert werden.