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The histochemical and electron-microscopic investigations were performed on the functional aspects in the islet cells in starved rats, rabbits and guinea pigs.Histologically, in starved animals, an atrophy of the B-cells was observed while the A-cells rather showed an increase in number.Ultramicroscopically, the alterations in the exhausted condition induced by starvation, as indicated by the appearance of lipid droplets or ceroid substance, were observed not only in the B-cells but also in the A-cells.On the contrary, in all starved animals, the tendency was demonstrated, electron-microscopically, that the B-cells appeared to be suppressed in their secretory function, whereas the A-cells appeared to be stimulated.Enzyme-histochemical observations on the islets after fasting showed a decrease in the activity of Ac-Pase (rat and rabbit), G6Pase (rabbit and guinea pig), 5′Nase (rat) and IDPase, while an increase in the activity was demonstrated on ATPase, nonsp. Est., Al-Pase (rat) and many of the enzymes concerning glucose oxidation.Enzyme activities in both the A-cells and the B-cells, determined histochemically, showed a synergistic alteration, and no antagonistic relationship was detected, although it was suggested under an electron microscope that, from the point of secretory function, the A-cells showed an antagonistic functional state to the B-cells.

The spectral radiance from a cylindrically shaped laser‐produced plasma in the ultraviolet region (200–300 nm) is shown to be 2–3 times greater than that produced by a xenon flashlamp of comparable size and input energy. The experimental results suggest several advantages of laser‐produced plasmas as sources for the optical pumping of lasers.

The first utilization of LPE for large scale production is for GaP light emitting diodes (LED's). In this paper we compare various approaches to multislice LPE and techniques of junction formation from the standpoint of LED fabriaction. A new technique involving a combination of thin melt epitaxy and vapor doping is emphasized as a method which is compatible with economic large scale production and state-of-the-art device performance. A detailed account of the growth procedure, surface quality and device performance is presented for a laboratory-prototype mass production system for green LED material.

The basis of this paper is comparative forced vibration testing of two GE 460 MW(e) BWR-type reactor buildings. The tested nuclear power plants are the Fukushima Nuclear Power Plant Unit No. 1 of the Tokyo Electric Power Company (hereinafter referred to as Fukushima) and the Shimane Nuclear Power Plant of the Chugoku Electric Power Company (Shimane). They are almost the same in both structure and function, but are built on rock of quite different rigidity. The shear wave velocity of Shimane is about three times that of Fukushima. The forced vibration tests were performed immediately after completion of each reactor building using a vibrator with a maximum exciting force of 3 t. The computer simulation analyses were carried out using vibration models possessing different internal viscous damping factors for each structural element. Both the resonance periods and damping factors of Fukushima were found to be larger than those of Shimane. Thus, site selection of nuclear power plants must be reviewed as a matter of utmost importance from the viewpoint of seismic design.

This investigation deals with a theoretical analysis of the characteristics of a fully developed turbulent helical flow in a concentric annulus, and an experimental program to verify the theoretical results. The results of the theoretical investigation include axial and tangential velocity distributions and the axial friction factors, with the inner cylinder of the annulus rotating at a constant speed. The theoretical results agree closely with the experimental ones. The variation of axial resistance of helical flow is shown to depend on the speed ratio for a given geometry.

The crystallization of an aggregate of the protein subunit of tobacco mosaic virus is described. Large single crystals suitable for X-ray analysis have been obtained, and an isomorphous heavy-atom derivative prepared.

A 50-ns pulse generator is used to obtain time-correlated current-voltage relationships in the prebreakdown region for a long vacuum gap with cold planar electrodes. Analysis of data indicates several sequential stages occur. These stages include an initial quiet stage of voltage increase without interelectrode current, a microdischarge stage, a field emission stage, a space-charge controlled stage, and a final low-impedance stage where the current becomes sustaining. Electrical breakdown of the gap is considered in terms of a positive ion front moving from the anode.

I. INTRODUCTION The problems of static electricity in the polymer industry are many and varied (see Table 1). They range from the removal of unwanted charge during fiber spinning and processing in order to avoid charging the machine and to reduce handling problems and dust pickup (fog marking), through the physiological problems associated with synthetic fiber carpets and automobiles to the explosion hazards of aircraft refueling, hospital environments, and mines. This is not to imply that all static is bad; in xerography, for example, the latent electrostatic image is developed by using toner (dry ink) charged by tumbling against the carrier; electrostatic separators make use of triboelectrification to accomplish separations not possible by other techniques.

A new alumina substrate with an extremely smooth surface was developed. This new alumina substrate includes Cr203and MgO as the additives. Reliability data and characteristics of tantalum nitride or tantalum and tantalum oxide films on the new substrate were compared with those on the glazed alumina.

An artificial heart in which the output is automatically controlled by the venous return, when implanted into dogs in the orthotopic position was found to be highly sensitive to changes in the hemodynamic conditions (a decrease in the venous return, hypo- and hypervolemia, increased peripheral resistance) and prevented the development of critical situations. For 24 h the principal vital functions of the experimental animals were maintained.

The etching of α-SiC crystals on various susceptors (tantalum, tantalum coated with tantalum silicide and tantalum carbide, and graphite) was studied in atmospheres of hydrogen and argon at temperatures between 1600–1850 °C. The studies were concerned with reactions occurring at the crystal-susceptor interface. It was found that in the case of tantalum susceptors, the above-mentioned reactions caused the formation of Si-Ta cubic phase based on silicon structure network. The rate of etching and the etch patterns formed on the bottom side of the crystals were related to the type of susceptor used. It was observed that impurities in the susceptor have a catalytic effect on the processes investigated. Photomicrographs of etched crystals are presented.

The effects of continuous dichoptic presentation of different sized grid patterns to the two eyes on monocular and binocular averaged visually evoked cortical responses (VERs) were investigated. Patterns (diffuse light and grids subtending between line distances of 15′, 30′ and 60′) were continuously presented to both eyes by means of a haploscope and VERs were elicited by a momentary increase in the brightness (10 μsec flash superimposed on the continuous luminance level) of the grid viewed by the left or right eye (monocular VERs) or both eyes (binocular VERs). Greater amplitude VERs were obtained when grids with elements subtending 15′ and 30′ were flashed for both monocular and binocular flash conditions. The effects of pattern presented to one eye depended on the pattern presented to the other eye. Binocular VER amplitude and binocular summation was greatest when identical sized pattern elements were presented to the two eyes and least when different sized pattern elements were presented to the two eyes (particularly when VERs were measured over the midline electrode position). When diffuse light was presented to one eye and patterned light to the other, binocular VERs reflected near complete suppression of the input from the eye viewing diffuse light, the amplitude and wave-form of the binocular VER being approximately the same as that of the monocular VER to the patterned light. Monocular VERs were influenced both by variations in pattern size presented to the eye receiving the increment in brightness (the evoking flash) and by the pattern size presented to the other eye which was not flashed. Monocular VER amplitude to the flashed eye progressively decreased as the elements presented to other non-flashed eye were varied in size from diffuse. 15′, 30′ to 60′ subtense, particularly when the flashed eye viewed diffuse light. There was a tendency for the effects of eye flashed (left vs right), interocular suppression, and binocular summation to be greater in VERs recorded over the right than the left cerebral hemispheres.

A canonic symmetric notch filter with grounded capacitors is presented. It has independent controls for Q-factor and notch frequency. It also provides low-pass and band-pass response across appropriate ports. An experimental circuit was built and tested for Q-values of 1, 10 and 100 at each of the notch frequencies of 60 Hz, 1 KHz and 5 KHz. There is excellent agreement between calculated and experimental results.

Light and electron microscope observations were made on colonies ofAspergillus nidulans treated before fixation with the ferricyanide reaction of Chevremont & Frederic. Sulphydryl groups, blockable by maleimide, were found at the conidiophore surface, internal to the wall, especially at the septa. Maleimide-stable reactivity, and at first some sulphydryl reactivity, was associated with the pigmenting regions of the exterior of the wall. No reactivity was found at any growing apex and none on the cell surface until the end of a budding cycle. The free sulphydryl groups were, therefore, associated with cell surface activity in the maturing cell immediately prior to pigmentation.

Various sources of distortion in class A junction transistor amplifier stages are investigated using a unified method of analysis. Expressions for simultaneous cancellation of second and third harmonic distortions at low frequencies are derived giving the design relations between the source and load resistances together with the transistor operating parameters. High frequency effects are considered and a simple compensating method is devised to extend the gain-bandwidth product to the order of (1/2°CTCrb′b).

A study is made of the oscillatory spectral distribution of the photovoltaic effect of a gold–germanium Schottky barrier in quantizing magnetic fields. The spectra are taken at 4.2 K in the Faraday configuration for fields of up to 70 kG. The results are analyzed in terms of the Pidgeon and Brown coupled bands theory of interband magneto-absorption. Excitonic effects are observed and discussed.

The differential cross section has been measured for the reaction γ +p→ π o + p at the Bonn 2.5 GeV electron synchrotron in the energy range from 0.55 to 2.2 GeV at a c.m.angle of 120 degrees.

Two-step photodissociation of molecules is considered. Spatial radiation absorption is taken into account. Appropriate estimations and numerical calculations are presented. Conclusions are drawn about two-step photodissociation efficiency and quantum yield.

Image tube filter photographs taken in the light of the low ionization energy [Nii] and high ionization energy [Oiii] lines of the core of M42 are presented. These were taken with the 98-in. Isaac Newton telescope. The whole core of M42 appears to be a complex of ionization fronts. An [Nii] photograph of M8 also suggests that the whole of this Hii region is composed of a mass of fronts penetrating into a huge neutral region containing dust, gas and molecules.

We study a transmission problem for quasi-elliptic differential operators (not necessarily of the same type) on a product manifold using pseudo-differential methods.

The effects of diffused nickel on the interface of silicon and a thermally grown oxide are examined. Information regarding effective fixed charge at the interface, surface state distribution and surface state type, is derived from capacitance-voltage characteristics of metal-oxide-semiconductor capacitors made with nickel doped and non-nickel doped silicon. Nickel doping is shown to reduce the density of effective surface states with energies more than 0·15 eV below E i , and to remove effective charge at the interface of the order of 0·1 μC/cm 2 .

An analysis has been made to examine the effect of a constant applied electrolysing voltage on the performance of an isothermal batch electrochemical reactor in which the rate of the cathodic reaction is limited by mass transfer of a reactant to the electrode surface, a simultaneous secondary reaction occurring at higher cathode potentials. Numerical solutions are presented for a hypothetical process study to show how average production rates for various percentage conversions of reactant are influenced by the magnitude of the electrolysing voltage and the corresponding electrical energy requirement. The most noticeable effect is that the electrical energy requirements for a given production rate are very strongly influenced by both the degree of conversion of reactant and by the extent to which the secondary reaction occurs.

N-Methyl phenazinium radical cation (MPH+•) is known to interact with DNA in a manner analogous to an acridine dye (1). In the present communication, we have investigated the interaction of MPH+• with single stranded polyriboadenylic acid (poly A) through the combined use of electron paramagnetic resonance (EPR) and Fourier-transform proton magnetic resonance (FT-PMR). Use of a paramagnetic dye enables us to obtain average distances between three protons of poly A nucleotide and the unpaired electron on the dye, giving direct evidence for the π-π complexation of the dye with the adenine base. In addition, kinetic parameters for the complexation reaction are evaluated.

The net. gain of n travelling-wave maser operating at 4-2°K in the frequency range 1680-1050 MHK haa been improved by heat treatment of the active material, chromium-doped rutile (Cr-TiO2). The heat treatments investigated, diffusion doping, quenching, and annealing were performed in a nearly hydrogen-free atmosphere of oxygen at 1200°C. The maximum net gain with a 3dB bandwidth of 6 MHz was 35 dB at 4·2°K and 1800 MHz. The length of the slow-wave structure was 55 mm. The net gain per unit length is the highest hitherto obtained.

The low temperature behaviour of semiconductor diodes, Zener diodes, varactor diodes, tunnel diodes, of bipolar transistors, and of field effect transistors is investigated. It is discussed which semiconductor materials and devices are best suited for use at 4.2 K. A great number of currently available diodes and transistors have been tested. The ones working satisfactory at 4.2 K are listed and their performance in cryogenic environments is described.

A new instrument has been devised, based on light scattering principles, to measure real‐time concentration variation in a turbulent flow. Used for turbulent diffusion measurements in a wind tunnel boundary layer, it can also be utilized for other turbulent mixing studies as well. The instantaneous concentration was detected by means of a 5 mW He–Ne gas laser as a light source, dioctyl phthalate aerosols as tracer particles, fiber optics as the scattered light transmitter, and a photomultiplier as a scattered light sensor. The instrument was designed to be moved to any location in a wind tunnel to measure steady or unsteady diffusion processes.

Low-voltage triode sputtering is a film deposition process capable of high deposition rates (100–600 A/min) using voltages less than 500 V and Ar pressures of about 1 μ. This paper considers the geometric aspects of low-voltage triode deposition which include: (1) the thickness uniformity over the substrate table; (2) step coverage; and (3) the geometric conditions that give the best thickness uniformity, step coverage, and maximum utilization of target area.

Irradiation of fiber optic waveguides with X-rays, gamma-rays, electrons, or neutrons can cause luminescence and losses in optical transmission. These effects have been measured, using pulsed and continuous radiation sources, in bulk materials and in most commercially available fiber bundles. Some important effects of dopants and impurities such as Ge, Ti, Fe, Al, and OH on radiation-resistance have also been determined. Transient absorption and luminescence were measured from 10 ns to 0.1s after irradiation (10 to 106 rads and 109 to 1013 rads/sec), and the permanent absorption was measured from 24 to 72 hours after irradiation (103 to 109 rads). These results show that synthetic vitreous silica (undoped), some doped silicas, polymethylmethacrylate and polystyrene can be used in radiation environments that are encountered in space and military applications. The utility of each of these fibers depends on the particular radiation environment, the length of waveguide, the wavelength of signal light, the time any system can be “off the air”, and constraints imposed by fiber cost. The data can be used to determine the response of actual fiber systems during and after irradiation.

An electron stereoscan microscope is used to examine the surfaces of an aluminum cathode and an aluminium anode which have been subjected to repeated sparkings, under an ultrahigh vacuum (10−9 Torr), at voltages of up to 45 kV. The cathode surface is observed to contain large numbers of protrusions which give rise to an enhanced local electric field at the tip of the protrusions. The field enhancement factor, β, at the microprojections is determined from the scanning electron micrographs. The values of β are in resonable agreement with those obtained from the Fowler‐Nordheim theory when applied to the current‐voltage measurements in the region prior to breakdown. The anode surface is completely devoid of protrusions and contains large numbers of craters. The diameters and the depths of typical craters are also determined.

In-space electric heating systems, such as baseboard, ceiling cable, wall fan, and radiant panel heaters, are customarily controlled by line-voltage or low-voltage thermostats. Tests show that the overall performance of such a heating system is significantly affected by the choice of thermostat used. Recent tests have shown that solid-state controls applied to such heaters can provide improved heating system performance. This paper presents performance test data whereby the performance characteristics of the various heating systems may be compared.

Measurements have been made of the viscosity of pure liquid 3 He at the saturated vapor pressure over the temperature range 20 mK to 1 K, by observation of the decay of torsional oscillations of a crystalline quartz cylinder. The results generally confirm previous measurements by other methods, but are more accurate and extend over a wider temperature range. Careful data analysis has been carried out to determine the best fit, which is given by the equation (ηT 2 )−1 =A 0 +A 1 T n , withA 0 =0.5450,A 1 =−1.594, andn=1 (with η in micropoise) and which indicates that higher-order terms inT (n>1) are inappropriate. The coefficientA 1 is four times larger than that given by theory which calculates it with use of only theZ 0 Landau parameter, indicating that other interaction parameters should be included.

Heating equimolar amounts of pure phosphoric and boric acids in aqueous solution yields, at 130°, a solid boron phosphate of the composition R = P2O5/B2O3 = 1:1.71. Increasing the calcination temperature to 575° increases R to 1:1.29 due to evaporation of boron-values. Further heating to 850° causes no additional weight losses. The specific surface decreases monotonically with the calcination temperature, from 7.4 to 0.5 m2/g. X-ray diffraction data indicate that up to 10 min heating at 800°, increased calcination temperature causes a monotonic decrease in the unit cell dimensions, while prolonged heating (48 h) at this temperature reverses this trend.

Two genes (hemB, hemC) taking part in the porphyrin biosynthesis of Bacillus subtilis were mapped. The gene hemB determines δ-aminolaevulinic acid dehydrase, and the gene hemC prophobilinogen deaminase. The transductants from the experiments were grouped by routine replica plating, and the genotypes of certain recombinant classes were determined by the syntropism of each transductant clone. The loci hemA, hemB and hemC are closely linked to each other and located between the leu-l and pheAl loci. These hem genes are situated on the chromosome according to the order of the biosynthetic pathway.

Recent experimental studies and clinical application of deep hypothermia for cardiovascular surgery are reviewed. At most institutions, surface hypothermia alone or in combination with limited cardiopulmonary bypass has been employed. Circulatory dynamics were well maintained following prolonged cardiac arrest at 20°C. Some degree of acidosis usually developed after the arrest period but was gradually corrected during rewarming. Total circulatory occlusion could be maintained for at least one hour at 20°C. without evidence of cerebral damage in infants. Many complex congenital cardiac anomalies, including transposition of the great arteries, total anomalous pulmonary venous return, ventricular septal defect, and tetralogy of Fallot, have been successfully corrected in the first few weeks of life. Less encouraging results have been achieved in patients with infradiaphragmatic total anomalous pulmonary venous return, complete atrioventricular canal, or pulmonary atresia.

The pseudo-orthorombic crystal structure of NdP5O14 was determined from three-dimensional MoKα diffractometer data. The true space group is P21/c, the lattice constants are a = 8.7672 , b = 8.9948 , c = 13.0326 A , β 90.48° , and there are four formula units per unit cell. The final R-factor with 3881 independent reflections was 0.038. The structure is built-up with discrete anionic ribbons linked by the cations in a complex way. The coordination of the cation by oxygen atoms is eight-fold with the geometry of a square antiprism.

A method is proposed for the determination of the efficiency of an yttrium aluminum garnet laser from the characteristics of its output radiation. It is shown that the product of the threshold energy and the maximum efficiency of a free-oscillation laser can be used to determine the concentration of active particles in a crystal and the energy capabilities of a Q-switched laser utilizing this crystal. A waveguide resonator was used to produce polarized radiation with an angular divergence close to the diffraction limit in one plane. The output power of a laser with this resonator was 30 W, which was the same as for a conventional Fabry–Perot resonator.

Studies on molecular motions at the surface of as-grown and annealed polyethylene single crystals in relation to the surface structure have been made by dispersing electron paramagnetic probes on the surface of the crystals and detecting them by the electron spin resonance method. A relatively large scale molecular motion supposedly associated with the glass transition was detected as a change in hyperfine patterns at around −50°C. Rotational correlation frequency of the paramagnetic probe was found to rapidly increase above the crystallization temperature suggesting that the new mode of molecular motion takes place by thickening of crystals. For the annealed crystals the frequency was much depressed compared with that of the as-grown crystals indicating the decrease in mobility of the surface by annealing. Extensive study revealed that the mobility of the surface of annealed crystals is uniquely determined by the increased portion of the lamellar thickness by annealing.

We have studied polarization effects associated with the diffraction of light from ultrasonic waves present in c-axis phonon masers. Experimental data are presented and compared with a theory which assumes that the ordinary and extraordinary components of the light beam are diffracted coherently.

The infrared fluorescence risetimes of the (ν1, ν4) and ν2 modes of CH3Cl have been measured after pumping the ν6 mode with a Q‐switched CO2 laser. The rates of rise were found to be 214 ± 60 msec−1 · torr−1 for (ν1, ν4) and 160 ± 45 msec−1 · torr−1 for ν2. Possible filling pathways for these modes are discussed, and infrared fluorescence rates for all modes in CH3Cl are summarized. The results are compared with similar intermode vibrational transfer rates in CH3F.

Techniques have been developed for measuring the strain and thermal histories of fluid elements as they move from the die lips to the freeze line. Motion pictures were analyzed to determine the rates of extension in the machine and transverse directions. A radiation pyrometer was used to measure the temperature of the film. These techniques were used to study the film blowing of polyethylene; a 2.5-in. diameter die was used, and blow-up ratios in the range of 1.8 to 3.4 were employed. Film thickness ranged from 2 to 4 mils. The maximum measured extensional strain rates in both the transverse and machine direction were in the range of 0.15 to 0.6 sec−1. Standard shrinkage and impact tests were performed on the finished films, and an attempt was made to correlate the results with several simple empirical norms of the strain history. No correlation could be discerned. The results of this study are inconsistent with some popular ideas about the origin of orientation in blow films, but they are consistent with some recently published data on the influence of deformation on orientation in melt-drawn capillary extrudate.

The slab-coupled waveguide, consisting of a dielectric rod lying on a slab that in turn covers a substrate, is a multidielectric waveguide that includes such special cases as the single-material fiber, the rib waveguide, and the strip-loaded film guide. These guides have recently become known as potentially useful either for long-distance optical transmission or for integrated optics. Simple, closed-form, approximate solutions have been found to describe the following properties of the guide: number of modes, their field configurations and propagation constants, numerical aperture, requirements for single-mode operation, field penetration in the slab, tolerance to curvature of the guide axis, dispersion, and impulse response.

The purpose of this study is to generalize the experimental method for deciding when a fluid motion can be considered turbulent. The rationale advanced for processing a transducer signal, which indicates the intermittent nature of a turbulent field, is given a probabilistic outlook. In addition an improved detector function is introduced which uses information from longitudinal and lateral fluctuation components.

A reaction mechanism and a correlation diagram argument are presented to account for the high photon yield of the chemiluminescent reaction of Ba atoms with N2O. Most BaO molecules appear to be formed initially in the long‐lived a3π state and to be transferred subsequently by collisions into the shorter‐lived A1Σ+ state. This mechanism accounts for numerous kinetic and spectroscopic observations of BaO. The arguments suggest that reactions of alkaline earth atoms with N2O and with O3 may be suitable for electronic‐transition chemical lasers.

An improved synthesis of thyrotropin releasing hormone (TRH), pGlu-His-Pro-NH2, is reported. Z-pGlu-ONB (N-hydroxy-5-norbornene-2,3-dicarboximide ester) was reacted with H-His-OH to yield a crystalline Z-pGlu-His-OH which was coupled with H-Pro-NH2 by the HONBDCC method to give Z-pGlu-His-Pro-NH2 as a fine crystal. Hydrogenation of this protected tripeptide yielded pure TRH nearly quantitatively. The optical purity of TRH thus obtained was confirmed by the method L- and D- amino acid oxidase digestion. The crystallization of TRH was achieved as a tartrate, and the properties of the crystalline TRH-tartrate are described.