bluuebunny/crossref_metadata_2025 huggingface dataset:
Acutely administered melatonin decreases somatostatin‐binding sites and the inhibitory effect of somatostatin on adenylyl cyclase activity in the rat hippocampus
Authors: Izquierdo‐Claros Rosa María , Boyano‐Adánez María del Carmen , Arilla‐Ferreiro Eduardo
Published: January 2004

Abstract:  Melatonin is known to increase neuronal activity in the hippocampus, an effect contrary to that of somatostatin (somatotropin release‐inhibiting factor, SRIF). Thus, the aim of this study was to investigate whether the somatostatinergic system is implicated in the mechanism of action of melatonin in the rat hippocampus. One group of rats was injected a single dose of melatonin [25 μg/kg subcutaneously (s.c.)] or saline containing ethanol (0.5%, s.c.) and killed 5 hr later. Melatonin significantly decreased the SRIF‐like immunoreactivity levels and induced a significant decrease in the density of SRIF receptors as well as in the dissociation constant (Kd). SRIF‐mediated inhibition of basal and forskolin‐stimulated adenylyl cyclase activity was markedly decreased in hippocampal membranes from melatonin‐treated rats. The functional activity of Gi proteins was similar in hippocampal membranes from melatonin‐treated and control rats. Western blot analyses revealed that melatonin administration did not alter Giα1 or Giα2 levels. To determine if the changes observed were related to melatonin‐induced activation of central melatonin receptors, a melatonin receptor antagonist, luzindole, was administered prior to melatonin injection. Pretreatment with luzindole (10 mg/kg, s.c.) did not alter the melatonin‐induced effects on the above‐mentioned parameters and luzindole, alone, had no observable effect. The present results demonstrate that melatonin decreases the activity of the SRIF receptor–effector system in the rat hippocampus, an effect which is apparently not mediated by melatonin receptors. As SRIF exerts an opposite effect to that of melatonin on hippocampal neuronal activity, it is possible that the SRIFergic system could be implicated in the mechanism of action of melatonin in the rat.
Suppression of melatonin biosynthesis in the chicken pineal gland by retinally perceived light – involvement of D1‐dopamine receptors
Authors: Zawilska Jolanta B. , Berezińska Małgorzata , Rosiak Jolanta , Skene Debra J. , Vivien‐Roels Berthe , Nowak Jerzy Z.
Published: January 2004

Abstract: In this study the role of retinal dopamine (DA) receptors in the light‐induced suppression of melatonin biosynthesis in the chicken pineal gland was examined. Exposure of dark‐adapted chickens to low intensity light (4 lux) at night significantly decreased the activity of serotonin N‐acetyltransferase (AA‐NAT; the penultimate and key regulatory enzyme in melatonin production) and melatonin content in the pineal gland. This suppressive action of light was blocked by intraocular (i.oc.) administration of SCH 23390 (a selective antagonist of D1‐DA receptors), but was not affected by sulpiride (a selective antagonist of D2‐DA receptors). Injection of DA (i.oc.) to dark‐adapted chickens significantly decreased pineal AA‐NAT activity and melatonin content in a dose‐ and time‐dependent manner. The action of DA was mimicked by selective agonists of D1‐DA receptors, SKF 38393 and SKF 81297, and non‐hydrolyzable analogs of cyclic AMP (cAMP), dibutyryl‐cAMP and 8‐bromo‐cAMP. However, i.oc. administration of quinpirole, a selective agonist of D2‐DA receptors, did not modify pineal AA‐NAT activity. In contrast, quinpirole potently decreased nocturnal AA‐NAT activity in the retina. Systemic administration of SCH 23390 to chickens blocked the i.oc. DA‐evoked decline in nighttime pineal AA‐NAT activity, whereas sulpiride was ineffective. These findings indicate that light activation of retinal dopaminergic neurotransmission, with concomitant stimulation of D1‐DA receptors positively coupled to the cAMP generating system, plays an important role in a cascade of events regulating pineal activity.
Central nervous α1‐adrenoceptor stimulation induces duodenal luminal release of melatonin
Authors: Sjöblom Markus , Flemström Gunnar
Published: January 2004

Abstract:  Intracerebroventricular (i.c.v.) infusion of the α1‐adrenoceptor agonist phenylephrine elicits vagal and sympathetic neural stimulation of the bicarbonate secretion by the duodenal mucosa. Melatonin originating from mucosal enterochromaffin cells (EC cells) has been proposed to mediate this centrally elicited stimulation. However, the release of intestinal melatonin has not been studied. Rats were anesthetized with thiobarbiturate, a 12‐mm segment of duodenum with intact blood supply was cannulated in situ and bicarbonate secretion titrated by pH‐stat. The mean arterial blood pressure was continuously recorded. Melatonin in the duodenal luminal perfusate was determined by high‐performance liquid chromatography with electrochemical detection. Intracerebroventricular infusion of phenylephrine (12.2 μmol/kg/hr) induced more than 10‐fold increase in release of melatonin into the duodenal lumen and an increase in HCO secretion from 7.6 ± 0.5 to 18.6 ± 2.1 μEq/cm/hr. The melatonin receptor (MT2 > MT1) antagonist luzindole (600 nmol/kg, i.v.) almost abolished the marked rise in bicarbonate secretion induced by i.c.v. phenylephrine but, in contrast, did not affect the release of melatonin. These results strongly suggest that release of melatonin from the mucosa mediates the duodenal secretory response to centrally elicited neural stimulation.
Melatonin receptor agonist 2‐iodomelatonin prevents apoptosis of cerebellar granule neurons via K+ current inhibition
Authors: Jiao Song , Wu Ming‐Ming , Hu Chang‐Long , Zhang Zhi‐Hong , Mei Yan‐Ai
Published: January 2004

Abstract:  Activation of K+ current plays a critical role in the control of programmed cell death. In the present study, whole‐cell patch‐clamp recording, a caspase‐3 activity assay, and flow cytometric analysis were used to examine the effects of the MT2 melatonin receptor agonist 2‐iodomelatonin on the delayed‐rectifier K+ current (IK) and the prevention of apoptosis. It was found that apoptosis of cerebellar granular neurons induced by low‐K+ (5 mm) incubation was associated with an increase in IK amplitude and caspase‐3 activity. After 6 hr of low‐K+ treatment, IK was increased by 45% (n = 86). Flow cytometry showed that the apoptosis rate increased by 333% compared with the control neurons. In addition, exposure of cultured granule cells to low K+ also resulted in a significant activation of caspase‐3, by 466%. 2‐Iodomelatonin (10 μm in injection pipette) inhibited the IK amplitude recorded from control cells and from cells undergoing apoptosis. However, 2‐iodomelatonin only modified the IK‐channel activation kinetics of cells under both conditions. Furthermore, 2‐iodomelatonin reduced the rate of apoptosis and caspase‐3 activation, by 66 and 64%, respectively. The melatonin receptor antagonist, 4P‐PDOT, abrogated the effect of 2‐iodomelatonin on the IK augmentation, caspase‐3 activity, and apoptosis. These results suggest that the neuroprotective effects of melatonin are not only because of its function as a powerful antioxidant, but also to its interactions with specific receptors. The effect of 2‐iodomelatonin against apoptosis may be mediated by activating a melatonin receptor, which modulates IK channels and reduces K+ efflux.
Attenuation of cold‐induced apoptosis by exogenous melatonin in carrot suspension cells: the possible involvement of polyamines
Authors: Lei Xiao‐Yong , Zhu Rui‐Yu , Zhang Gui‐You , Dai Yao‐Ren
Published: January 2004

Abstract:  Pretreatment with 43 nm (10 ng/mL) to 86 nm melatonin for 5 days significantly attenuated cold‐induced apoptosis in carrot suspension cells (Daucus carota L.) as evidenced by the TUNEL procedure, DNA fragmentation and the morphological changes revealed by electronic microscopy observations. The antiapoptotic effect of melatonin was initially thought to be a result of its antioxidant actions. In our study, however, reactive oxygen species (ROS) generation remained unaffected by melatonin treatment, suggesting that melatonin plays its protective role not related to its direct ROS scavenger. At the same time, notable increases in putrescine and spermidine levels were observed in melatonin‐treated cells, which may be responsible for the alleviation of the cold‐induced apoptosis. The possible involvement of polyamines in the antiapoptotic effect of melatonin was further confirmed by the inhibitory effect of exogenous polyamines on apoptosis as displayed by the DNA laddering assay.
Differential effects of light wavelength in phase advancing the melatonin rhythm
Authors: Wright Helen R. , Lack Leon C. , Kennaway David J.
Published: January 2004

Abstract:  Shorter wavelength light has been shown to be more effective than longer wavelengths in suppressing nocturnal melatonin and phase delaying the melatonin rhythm. In the present study, different wavelengths of light were evaluated for their capacity to phase advance the saliva melatonin rhythm. Two long wavelengths, 595 nm (amber) and 660 nm (red) and three shorter wavelengths, 470 nm (blue), 497 nm (blue/green), and 525 nm (green) were compared with a no‐light control condition. Light was administered via a portable light source comprising two light‐emitting diodes per eye, with the irradiance of each diode set at 65 μW/cm2. Forty‐two volunteers participated in up to six conditions resulting in 15 per condition. For the active light conditions, a 2‐hr light pulse was administered from 06:00 hr on two consecutive mornings. Half‐hourly saliva samples were collected on the evening prior to the first light pulse and the evening following the second light pulse. The time of melatonin onset was calculated for each night and the difference was calculated as a measure of phase advance. The shorter wavelengths of 470, 495 and 525 nm showed the greatest melatonin onset advances ranging from approximately 40–65 min while the longer wavelengths produced no significant phase advance. These results strengthen earlier findings that the human circadian system is more sensitive to the short wavelengths of light than the longer wavelengths.
Experimental investigation on cellular breakup of a planar liquid sheet from an air-blast nozzle
Authors: Park Jaewan , Huh Kang Y. , Li Xianguo , Renksizbulut Metin
Published: January 2004

The cellular breakup phenomenon is investigated experimentally for a planar liquid sheet from an air-blast nozzle. The dominant sinuous wave growing spatially downstream forms complicated cellular structures of perforated thin films and surrounding ligaments. Several characteristic parameters are measured from photographic images and compared with linear temporal analysis. The dominant wavelength is proportional to the inverse square of the relative velocity between air and liquid. The estimated breakup time matches the growth time of the most unstable wave, while the breakup length corresponds to a product of breakup time and liquid velocity. Numerical simulation shows a substantially reduced mean effective velocity near flow reattachment region of the air stream. Air turbulence seems to play a major role on initial perturbations of cellular breakup in the given nozzle configuration. The measured spatial growth rates are always less than linear predictions due to deviation from the linear regime at higher amplitudes.
EXCITATION OF SURFACE ELASTIC WAVES BY TRANSIENT SURFACE HEATING
Authors: Lee R. E. , White R. M.
Published: January 2004

The generation of surface elastic waves by the transient surface heating of piezoelectric and nonpiezoelectric solids is described. A Q-switched ruby laser produces the surface heating; the frequencies of the resultant surface waves are Fourier components of the laser waveform. The use of a spatially periodic illumination is shown to increase the effectiveness of generation at a selected frequency. This method of generating surface waves appears suitable for microwave frequency operation as well as operation at high wave amplitudes at low frequencies.
HELICON-SPIN WAVE INTERACTION IN THE MAGNETIC SEMICONDUCTOR AgxCd1−xCr2Se4
Authors: Vural B. , Thomas E. E.
Published: January 2004

The microwave transmission characteristics of the ferromagnetic semiconductor CdCr2Se4 doped with Ag have been measured as function of the applied magnetic and electric field. The results are interpreted in terms of active helicon-spin wave interactions; and the agreement between experiment and theory is found to be very good qualitatively.

It is believed that the results presented in this Letter represent the first published evidence for active helicon-spin wave interactions.
PRESSURE AND CURRENT DEPENDENT SHIFTS IN THE FREQUENCY OF OSCILLATION OF THE CO2 LASER
Authors: Mocker Hans W.
Published: January 2004

The shift of the frequency of oscillation of the 00°1–10°0 rotation-vibration band at 10.6 μ of a CO2 laser has been investigated as a function of total pressure, CO2 partial pressure, discharge current, and cavity mode position. The measurements were made by heterodyning two passively stabilized CO2 lasers, both oscillating in a single transverse mode and single frequency at the P branch of the 00°1–10°0 rotation-vibration band of CO2. The result yielded a 5–8 MHz/torr frequency shift toward red due to an increase in total pressure and a 500–900 kHz/mA shift toward blue due to an increase in excitation. The amount of frequency shift due to excitation was found to be independent of the location of the cavity resonance with respect to the Doppler center. The dependence on CO2 partial pressure was also determined.
SITE TRANSFER OF Si IN GaAs
Authors: Spitzer W. G. , Allred W.
Published: January 2004

Experimental evidence is presented which (1) allows quantitative determination of the redistribution of Si impurities between Ga and As sites after Li diffusion; (2) shows there is no loss of Si to complex or pair formation when NSi ∼ 1−2 × 1018 cm−3; and (3) indicates that the site symmetry of the Si is tetrahedral before and after redistribution.
LIGHT AMPLIFICATION IN SATURABLE ABSORBERS
Authors: Mack M. E.
Published: January 2004

It has been found that an absorber driven into saturation by a strong light pulse can amplify a weak light pulse simultaneously incident upon the medium. Gains as high as 20 cm−1 have been observed. This effect is believed to be related to the ability of a saturable absorber to bring about mode locking in a laser cavity.
OPTICAL PROBING OF MAGNETOSTATIC MODES IN YIG DELAY LINES
Authors: Collins J. H. , Wilson D. A.
Published: January 2004

Diffraction of infrared laser light from magnetostatic modes in yttrium iron garnet has been used to study the mechanism by which electromagnetic energy, fed to a grounded wire antenna at one end of an axially magnetized crystal, is converted to exchange-spin-wave energy. The properties exhibited by the diffraction support the theory in detail.
HIGH CONDUCTIVITY p-TYPE CdS
Authors: Chernow Fred , Eldridge Graeme , Ruse Guy , Wåhlin Lars
Published: January 2004

High conductivity p-type CdS was formed by ion implanting Bi into n-type single crystals. Hall measurements and lifetime studies were performed on the implanted layers. p-n junctions were formed in high conductivity n-type material and light emission observed in the forward direction. By making two independent contacts to the p-type layer and measuring their I-V characteristics, it was determined that they were not rectifying.
OBSERVATION OF CURRENT FILAMENTS IN SEMI-INSULATING GaAs
Authors: Barnett A. M. , Jensen H. A.
Published: January 2004

Two-carrier injection into semi-insulators can cause a current controlled negative resistance. The observation of current filaments in the high conductance region has been reported for an indirect energy gap semiconductor, silicon, at 77°K. These current filaments have now been observed in gallium arsenide, a direct energy gap semiconductor, at room temperature.
TRANSMISSION BANDWIDTH REDUCTION OF HOLOGRAPHIC STEREOGRAMS RECORDED IN WHITE LIGHT
Authors: De Bitetto D. J.
Published: January 2004

A three-step method is described for obtaining holograms of 3D objects illuminated in white light. A horizontal linear array of n lenslets is used to simultaneously photograph a 3D scene. The resulting array of n 2D images is transformed into a thin horizontal strip hologram, using coherent light. Multiple (n) identical copies of this strip hologram are contiguously arranged in a vertical column, resulting in an n × n array of elemental holograms for viewing of the virtual image of the 3D scene. Horizontal parallax is preserved; vertical parallax is sacrificed to reduce the bandwidth required for transmission by a factor n.
LONGITUDINAL VIBRATION INDUCED IN METALS BY THERMAL SHOCK
Authors: Kendall Paul A.
Published: January 2004

A wire Joule-heated by a current pulse will be set into harmonic oscillation as a result of its rapid bulk expansion. The experimental setup and results are discussed. Young's modulus is obtained for three sample materials, and other possible applications are considered.
LONG-WAVELENGTH INFRARED Pb1−xSnxTe DIODE LASERS
Authors: Butler J. F. , Harman T. C.
Published: January 2004

Diode lasers with emission wavelengths as long as 28 μ have been fabricated using Pb1−xSnxTe with x up to 0.27. Properties of laser diodes at 77°K and 12°K have been measured for a number of compositions in the range 0.15 ≤ x ≤ 0.27. The vapor growth and annealing-diffusion steps were performed in a special quartz ampoule which remained sealed throughout the process. Threshold current densities were dependent on diode surface conditions and could be reduced by at least 50% by etching.
KNb3O8—A MICA-LIKE CRYSTAL
Authors: Nassau K. , Shiever J. W.
Published: January 2004

Large single crystals of KNb3O8 were pulled from the slightly off-stoichiometric melt. Both the unusually developed cleavability and the electrical properties such as dielectric constant, loss tangent, and dielectric breakdown strength are similar to those of mica. This material shows promise both as a substitute for mica and as an interesting new dielectric in its own right.
SELECTIVE ABSORPTION CHANGES IN Fe-DOPED CdTe UNDER THE INFLUENCE OF HIGH ELECTRIC FIELDS
Authors: Fenner G. E.
Published: January 2004

Experiments with Fe-doped CdTe samples at about 15°K show that when large electric fields are applied to a crystal in the presence of mobile electrons, selective changes in the optical absorption near 4.5 μ occur. Significant increases in the absorption for wavelengths >4.38 μ and accompanying decreases in the absorption for λ < 4.38 are thought to be caused by the interaction of hot electrons with the Fe2+ ions.
LASER-INDUCED ``BLOW-OFF'' PHENOMENA
Authors: Skeen C. H. , York C. M.
Published: January 2004

A high-power, Q-switched, neodymium-doped glass laser was used to create a blow-off plasma at surfaces of solid materials. Measurements of the ensuing stress pulses and the associated phenomena are discussed.
FAST PHOTOCONDUCTIVITY OF TELLURIUM BY CO2 LASER RADIATION
Authors: Miura Noboru , Tanaka Shoji
Published: January 2004

Very fast photoconductivity was observed in tellurium single crystals which were excited by a CO2 laser. The photoconductivity follows completely the Q-switched laser pulses, and the carrier lifetime is estimated to be of the order of 10−12 sec.
CW PARAMETRIC SCATTERING IN ADP WITH STRONG ABSORPTION IN THE IDLER BAND
Authors: Giallorenzi T. G. , Tang C. L.
Published: January 2004

Results on the signal intensity and collinear tuning characteristics in CW optical parametric scattering in ADP pumped at 4880 Å are presented and discussed. The corresponding idler wave is in a strong absorption region of ADP.
Q SWITCHING AND MODE LOCKING OF A CF3I PHOTOLYSIS LASER
Authors: Ferrar C. M.
Published: January 2004

Peak power in excess of 1 MW, at 1.315-μ wavelength, has been obtained by Q switching a small gaseous CF3I photolysis laser operating in a single axial cavity mode. When several axial modes oscillate, mode locking produces periodic pulsing of the Q-switched output with somewhat enhanced peak power.
SELF-Q-SWITCHING IN RUBY LASERS
Authors: Freund Isaac
Published: January 2004

A laser consisting solely of a pumped ruby rod and rear reflector has been operated so as to produce single giant pulses.
UNDAMPED REGULAR SPIKING OF A RUBY LASER IN A MISALIGNED CAVITY
Authors: Greenhow R. C. , Schmidt A. J.
Published: January 2004

Regular spiking of a ruby laser has been observed in a cavity with two plane mirrors, one of which was tilted. With the introduction of a lens the regularity and reproducibility of the regular spiking was improved considerably.
A NEW METHOD OF GIANT PULSING RUBY LASERS
Authors: Collins R. J. , Braun L. O. , Dean D. R.
Published: January 2004

Giant pulses have been obtained from a ruby laser by a new technique. This technique provides control of the output pulses by the static misalignment of the cavity. No additional cavity elements were required for the production of giant pulses. Relative enhancement in the peak power by misalignment has been studied as a function of two cavity parameters.
ELECTRONIC SIMULATION OF A VARIABLE INCLINATION REFERENCE FOR ACOUSTIC HOLOGRAPHY VIA THE ULTRASONIC CAMERA
Authors: Mueller R. K. , Marom E. , Fritzler D.
Published: January 2004

Images have been optically reconstructed from acoustic holograms obtained by electronic scanning of a piezoelectric crystal receiver and an electronic signal simulating an artificial reference plane wave. An inclined acoustic reference wave whose angle of incidence could be varied was synthesized electronically.
THERMALLY STIMULATED CURRENTS AND LUMINESCENCE IN RUTILE (TiO2)
Authors: Addiss R. R. , Ghosh Amal K. , Wakim F. G.
Published: January 2004

A weak luminescence emission band at 850 mμ was found in rutile cyrstals, and a series of shallow electron traps (<1 eV) were detected in thermally stimulated current and thermoluminescence curves, both of which show the same eight peaks in the temperature range of −190 to +100°C. These results are characteristic of all samples examined, including crystals from two different sources, crystals having different orientations, and crystals having different amounts of reduction within a limited range.
FREQUENCY MIXING IN THE INFRARED AND FAR-INFRARED USING A METAL-TO-METAL POINT CONTACT DIODE
Authors: Hocker L. O. , Sokoloff D. R. , Daneu V. , Szoke A. , Javan A.
Published: January 2004

Metal-to-metal point contact diodes were used to obtain the 54-GHz beat notes between two adjacent 10.6-μ CO2 laser transitions. The speed of the diodes in the far-infrared is at least 1000 GHz. This was tested with a 337-μ HCN laser.
A UNIVERSAL PLANAR X-RAY RESONATOR
Authors: Cotterill R. M. J.
Published: January 2004

A planar x-ray resonator, the tuning of which is exact, can be constructed from a suitable arrangement of an even number of Bragg reflectors, pairs of which are parallel.
LOW FREQUENCY CURRENT FLUCTUATIONS IN A GaAs GUNN DIODE
Authors: Matsuno Koichiro
Published: January 2004

Low frequency noise spectrum and electrical conductivity of a GaAs Gunn diode are presented. Based on these results, we suggest that the observed FM noise spectrum of Gunn oscillators with −9 dB/octave slope of noise-to-carrier ratio may also be due to current fluctuations with l/f characteristic resulting from electron trapping.
SPUTTERING DUE TO NEGATIVE OXYGEN IONS IN OXYGEN DISCHARGES
Authors: Jennings Thomas A. , McNeill William
Published: January 2004

The effect of gaseous negative oxygen ion impact on an anode surface is examined. Gold films (≈300 Å) are sputtered at a pressure of 30–35 mtorr and at several anode voltages and currents. Results show a linear dependency of the sputtering rate on the applied anode voltage up to 95 V, while at higher voltages there is little change in the sputtering rate. The sputtering yield shows a decreasing nonlinear dependence on the applied anode voltage. The latter is explained in terms of the decrease in the electronegative character of the discharge.
ULTRASONIC HOLOGRAPHY BY ELECTRONIC SCANNING OF A PIEZOELECTRIC CRYSTAL
Authors: Marom E. , Fritzler D. , Mueller R. K.
Published: January 2004

Images have been optically reconstructed from acoustical holograms displayed by electronic scanning of a piezoelectric crystal, irradiated by the sonic beams.
INTERPRETATION AND MECHANISM OF THE CS2–N2 LASER
Authors: Legay-Sommaire Nicole
Published: January 2004

A new interpretation of the CS2–N2 laser lines is proposed. The lines are attributed to the 0201–1200 transition. The abnormal intensities observed for two lines are interpreted as arising from their coincidence with two lines of the 0221–1220 system.

The interpretation is consistent with the hypothesis of a vibrational transfer from N2.
PICOSECOND SUBSTRUCTURE OF LASER SPIKES
Authors: Shapiro S. L. , Duguay M. A. , Kreuzer L. B.
Published: January 2004

The two-photon fluorescence technique has been used to examine, on a picosecond time scale, the output of a long-pulse (non-Q-switched) Nd:glass laser. The well-known ``spikes,'' about 200 nsec wide, are found, in many cases, to consist of a large number of ultrashort pulses, about 3 psec in duration. In a non-Q-switched ruby laser, pulses about 15 psec in duration have been seen.
POLYMORPHISM IN VACUUM-DEPOSITED GaP FILMS
Authors: Davey John E. , Pankey Titus
Published: January 2004

GaP films have been vacuum-deposited onto amorphous substrates by a three-temperature zone technique. When the films are deposited at elevated temperatures (>500°C) and under a condition of Ga excess, whisker, rod and platelet growth occur in the film. Transmission electron diffraction examination has shown a polymorphic form of GaP to exist in these deposits.
MEASUREMENTS ON THE RAMAN COMPONENT OF LASER ATMOSPHERIC BACKSCATTER
Authors: Cooney J. A.
Published: January 2004

Density profiles of the gaseous atmosphere up to 3 km have been measured using laser backscatter. The ambiguity in the return at the laser frequency (6943 Å) due to the aerosol scatter component was avoided by monitoring the frequency-shifted Raman vibrational-rotational band of the nitrogen component centered at 8285 Å.
RESOLUTION OF PULSED LASER HOLOGRAMS
Authors: LaMacchia J. T. , Bjorkholm J. E.
Published: January 2004

Measurements were made of the resolution of holograms formed with a Q-switched ruby laser operating in a single longitudinal and transverse mode. Diffraction limited, 4 μ detail was observed in the reconstructed real image as viewed in CW He–Ne illumination.
THE GROWTH OF LASER OSCILLATIONS
Authors: Born Gunthard K.
Published: January 2004

The buildup of low-gain laser oscillations is observed by a simple experimental method: A helium-neon laser is ``switched on'' by mechanically unblocking the space inside the vacity between a Brewster-angle window of the discharge tube and an (external) mirror. The resulting growth of a low-power laser signal is found to follow the predictions of Lamb's theory.
FARADAY ROTATION, SPECTRAL EMITTANCE, AND HALL EFFECT OF GALLIUM ANTIMONIDE
Authors: Liang C. Y. , Piller H. , Stierwalt D. L.
Published: January 2004

Based upon the two-band model, a combined analysis of the experimental data of GaSb obtained from Faraday rotation, spectral emittance, and Hall effect measurements is discussed.
ACCELERATION OF MICROPARTICLES BY LASER-INDUCED VAPOR EMISSION
Authors: Waniek Ralph W. , Jarmuz Paul J.
Published: January 2004

The interaction of intense laser beams against single charged particles was investigated to determine the possibility of acceleration by surface evaporation. Aluminum particles of 25 μ diam, freely suspended in a time-varying electric field possessing focusing properties, were located within the focal spot (100 μ diam) of the normal output of a ruby laser. The individual laser spikes contribute to the stepwise acceleration of the particle and serve simultaneously for stroboscopic observation of the trajectory. With power densities of 106 W/cm2 and beam energies of a fraction of a joule, the recoil pressure due to the vaporization of the material produced directed velocities of 2 · 104 cm/sec. The present results agree with momentum conservation involving vaporization of a fraction of the particle material.
MODE LOCKING OF AN ORGANIC DYE LASER
Authors: Glenn W. H. , Brienza M. J. , DeMaria A. J.
Published: January 2004

This Letter reports the mode locking of an organic dye laser achieved by pumping the laser with the second harmonic of a mode-locked pulse train from a Nd laser. Mode-locked laser action was observed for solutions of Rhodamine 6G and Rhodamine B and mixtures thereof. The laser output could be varied from about 5600 Å–5900 Å by changing the composition of the solution.
MULTIPLE PULSE EMISSION FROM A HCN LASER
Authors: Turner R. , Hochberg A. K. , Poehler T. O.
Published: January 2004

The time dependence of the output of a high-energy HCN laser has been studied with an indium antimonide detector. At a CH3CN partial pressure of 0.24 torr, three separate infrared pulses are emitted during a 250 μsec time interval after the current pulse. The addition of He, A, O2 or H2 changes both the number and delay between the pulses. As many as six pulses approximately 90 μsec apart in a 450 μsec period are observed with a He–CH3CN gas mixture.
Al2O3-SILICON INSULATED GATE FIELD EFFECT TRANSISTORS
Authors: Waxman A. , Zaininger K. H.
Published: January 2004

MOS transistors, with aluminum oxide as gate insulator, have been fabricated. The Al2O3 films were formed by first depositing aluminum on freshly cleaned 10 Ω-cm silicon and then anodizing the aluminum in an oxygen plasma. All other steps used standard silicon technology. Electron diffraction showed that the insulator films are amorphous. The index of refraction is between 1.67 and 1.70 and the relative dielectric constant is 7.6. The devices have a threshold voltage of between ±0.5 V, and an interface state density of about 2 × 1010 states/cm2-eV. No evidence for ionic motion under positive bias was found at elevated temperatures. Under 1 MeV electron bombardment at various fluence levels and bombardment biases these devices showed excellent radiation resistance. Their radiation behavior is better than that observed for MNS or ``hardened SiO2'' devices.
INTERACTION OF LITHIUM WITH OXYGEN AND DEFECTS IN SILICON
Authors: Fang P. H. , Liu Y. M. , Carter J. R. , Downing R. G.
Published: January 2004

Spontaneous annealing was observed at room temperature of the electron irradiation induced defect in lithium diffused oxygen-rich silicon. Some implications of this observation are discussed.
LASER ACTION IN FIELD-IONIZED BULK GaAs
Authors: Southgate P. D.
Published: January 2004

Stimulated emission of recombination radiation has been observed at 78°K in n-type GaAs ionized by the passage of Gunn domains. Output pulses are about 2 nsec long, and have a bandwidth of 30 Å; more than half the light is emitted within 8° of the normal to the polished specimen face.
MOVING MASK GROWTH OF SINGLE-CRYSTAL SILICON FILMS ON AMORPHOUS QUARTZ SUBSTRATES
Authors: Braunstein M. , Henderson R. R. , Braunstein A. I.
Published: January 2004

We have combined vapor-liquid-solid mechanisms with a moving-mask-growth technique in a study of the nucleation and condensation of single-crystal silicon films deposited on amorphous dielectric substrates by vacuum evaporation of silicon. Using this VLS-MMG approach we have grown silicon single crystals up to 50 × 300 μ in lateral dimension on fused quartz substrates at substrate temperatures of 800 to 900°C.
LASER BACKSCATTER CORRELATION WITH TURBULENT REGIONS OF THE ATMOSPHERE
Authors: Lawrence J. D. , McCormick M. P. , Melfi S. H. , Woodman D. P.
Published: January 2004

An instrumented jet aircraft has been used to probe regions of the clear atmosphere where an enhancement of radiation backscattered from a ground-based ruby laser was observed. In twenty-seven cases, established over five nights of observation, the aircraft encountered light turbulence in clear air in regions of enhanced backscattering.
PHOTOEMISSION FROM InP-Cs-O
Authors: Bell R. L. , Uebbing J. J.
Published: January 2004

Photoelectric measurements on cleaved p+ InP show that a process of cesiation and oxidation can produce a work function lower than the InP bandgap. Efficient photoemission results, with luminous efficiencies of 450 μA/lumen or better, and a threshold at 1.24 eV (1 μ).
INFLUENCE OF IONIZED IMPURITY SCATTERING ON GUNN EFFECT AND IMPACT IONIZATION IN CdTe
Authors: Picus Gerald S. , DuBois Donald F. , Van Atta Lynette B.
Published: January 2004

Recombination radiation from electron-hole pairs generated by impact ionization has been observed in heavily doped CdTe at electric field intensities higher than those required to produce Gunn oscillations in lightly doped material. The suppression of the Gunn effect in the more heavily doped CdTe is attributed to a decrease in the magnitude of the negative differential mobility displayed by the drift velocity vs electric field characteristic resulting from the presence of ionized impurity scattering.
EVIDENCE FOR SUPERRADIANCE IN THE RECOMBINATION RADIATION FROM CdTe
Authors: Van Atta Lynette B. , Picus Gerald S. , Yariv Amnon
Published: January 2004

Linewidth narrowing attributed to superradiance has been observed in near bandgap radiation due to the recombination of impact ionized carriers in n-type CdTe at room temperature. The light emission was associated with a current breakdown that occurred at a threshold field of 12,000 V/cm in highly compensated n-type samples.
CURIE TEMPERATURE, BIREFRINGENCE, AND PHASE-MATCHING TEMPERATURE VARIATIONS IN LiNbO3 AS A FUNCTION OF MELT STOICHIOMETRY
Authors: Bergman J. G. , Ashkin A. , Ballman A. A. , Dziedzic J. M. , Levinstein H. J. , Smith R. G.
Published: January 2004

The Curie temperature, birefringence, and phase-matching temperature of LiNbO3 are shown to vary with the stoichiometry of the melt from which the crystals are pulled. The range of melt stoichiometry, indexed by the Li/Nb mole ratio, was varied from 1.20 to 0.80. This Li/Nb variation changes the Curie temperature, refractive index for the extraordinary ray, and the phase-matching temperature by 120°C,.03, and 320°C respectively. The relevance of these changes are discussed in terms of the susceptibility of LiNbO3 to index inhomogeneities.
SURFACE STATES IN SILICON FROM CHARGES IN THE OXIDE COATING
Authors: Goetzberger A. , Heine V. , Nicollian E. H.
Published: January 2004

The experimentally observed distributions of surface state density versus energy is correlated with the existence of coulombic centers in the oxide. Single charges give rise to peaks in surface state density close to the band edges, deeper levels are introduced by two charges in close proximity.
OBSERVATIONS OF NONCOLLINEAR PHASE MATCHING IN OPTICAL PARAMETRIC NOISE EMISSION
Authors: Smith R. G. , Skinner J. G. , Geusic J. E. , Nilsen W. G.
Published: January 2004

Measurements of optically excited parametric noise which demonstrate the importance of noncollinear phase matching are presented. The absolute magnitude of the emitted noise has also been measured and is found to be in excellent agreement with theory.
MODULATION OF OPTICAL ABSORPTION AT THE INTRINSIC EDGE BY ACOUSTOELECTRIC DOMAINS IN n-GaAs
Authors: Spears David L. , Bray Ralph
Published: January 2004

The enhancement of optical absorption by propagating acoustoelectric domains is observed in n-GaAs at 77°K. The spectral dependence of this absorption corresponds to an exponential broadening of the intrinsic absorption edge. Several possible mechanisms for this effect are considered in terms of the electric field and the acoustic flux present in the domain.
ASSIGNMENT OF SOME DCN AND HCN LASER LINES
Authors: Maki Arthur G.
Published: January 2004

The far-infrared laser lines in DCN are explained as being due to transitions involving the 2200 and 091c0 levels which are mixed by a Coriolis resonance at J = 21. The HCN laser lines near 130 μ are explained by a Coriolis resonance which affects the 1200, 1220, and 0510 levels. New laser transitions are predicted for these systems.
ABSOLUTE FREQUENCY MEASUREMENTS OF NEW CW DCN SUBMILLIMETER LASER LINES
Authors: Hocker L. O. , Javan A.
Published: January 2004

New CW laser lines at 204 μ, 195 μ, and 190 μ have been made to oscillate as pure rotational cascade transitions pumped by the 195 μ and 190 μ DCN lines. Frequency measurement of three of these new lines confirms the identification of all these lines.
EFFECT OF INHOMOGENEOUS MINORITY CARRIER DISTRIBUTIONS IN ELECTRON-BEAM-PUMPED LASERS
Authors: Klein C. A. , Lavine J. M.
Published: January 2004

Power output versus beam current characteristics of electron-beam-pumped semiconductor lasers do not exhibit a linear dependence pattern. We demonstrate that this behavior reflects the nonuniform nature of the steady-state distribution of bombardment-induced minority carriers. The treatment suggests a novel method of assessing the diffusion length in semiconductors; for laser-grade n-type GaAs we find L ≲ 1 μ.
SATURATION OF POWER OUTPUT OF A PULSED ION LASER IN VERY HIGH CURRENT REGIONS
Authors: Hattori Shuzo , Goto Toshio
Published: January 2004

Inductive excitation was employed to produce pulsed discharge currents of more than 1000 A. The I.D. of a wide bore tube used was 1 cm, in which laser oscillation has been observed at four ion lines with pure argon at a pressure of about 15 mtorr. It has been found that current dependence of the laser output power at the 4765 Å line is very different from that at the other three lines.
X-RAY MONOCHROMATORS AND RESONATORS FROM SINGLE CRYSTALS
Authors: Deslattes Richard D.
Published: January 2004

Single-crystal specimens shaped so as to permit successive x-ray diffraction by two nonparallel atomic planes are fixed wavelength monochromators. It is shown that certain plane pairs in Si and Ge pass wavelengths sufficiently close to strong characteristic lines to allow production of intense highly monochromatic beams. For tautozonal planes belonging to the same crystal form, resonators and retroreflectors are possible.
EFFECTS OF MULTIPLY-CHARGED GOLD IMPURITY ON THE BREAKDOWN VOLTAGE OF SILICON P-N JUNCTIONS
Authors: Sah C. T. , Schroder D. K.
Published: January 2004

In the transition-depletion region of both P+N and N+P step silicon junctions, gold impurity is in the negatively charged acceptor state. It decreases the net charge in the transition region of the P+N case and increases the net charge in the transition region of the N+P case. This results in a corresponding increase and decrease respectively of the breakdown voltage of these cases. Experimental data obtained show very good correlation with this model.
A NEW KIND OF RAPID-SCAN MONOCHROMATOR USEFUL FOR ANALYZING CHEMICAL LASERS
Authors: Gregg David W. , Thomas Scott J.
Published: January 2004

A new rapid-scan monochromator useful for analyzing chemical lasers has been evaluated. It consists of using a grating as part of the laser cavity and rotating one of the laser mirrors. The lasing lines are individually Q-switched, increasing their intensities by a factor of 105. No limitation was found in the scan speed, and the theoretical spectral resolution of the grating was achieved. Because of the wavelength selection in the laser cavity, lines are brought out which otherwise would not lase.
RADIATION EFFECTS IN METAL-INSULATOR-SEMICONDUCTOR CAPACITORS AS DETERMINED FROM CONDUCTANCE MEASUREMENTS
Authors: Perkins C. W.
Published: January 2004

Conductance-versus-voltage measurements were employed to determine the distribution of fast interface states in MOS and MNS capacitors and the changes in these distributions due to gamma irradiation with applied bias. MNS samples showed no changes due to irradiation, while MOS samples showed an increase in the conductance peak due to an increase in the density of the fast states.
SINGLE-CRYSTAL GALLIUM ARSENIDE ON INSULATING SUBSTRATES
Authors: Manasevit Harold M.
Published: January 2004

Chemical vapor deposition has been been used successfully for the attainment of a single-crystal growth of gallium arsenide directly on a number of single-crystal insulating oxide substrates. Several orientation relationships have been determined for GaAs grown on sapphire (α-Al2O3), spinel (MgAl2O4), beryllium oxide (BeO), and thorium oxide (ThO2).
TUNNELING INTO AMORPHOUS GERMANIUM FILMS
Authors: Nwachuku A. , Kuhn M.
Published: January 2004

Electron tunneling into amorphous germanium films was studied using Al–Al2O3–Ge tunnel junctions. A ``conductance well'' was observed, which is related to the band edges of the amorphous germanium film and its surface potential. Structure in the conductance well is interpreted as tunneling into gap states. The results suggest tunneling as a possible tool for the study of band structure in amorphous materials.
SELF-TRAPPING IN MEDIA WITH SATURATION OF THE NONLINEAR INDEX
Authors: Gustafson T. K. , Kelley P. L. , Chiao R. Y. , Brewer R. G.
Published: January 2004

Numerical solutions of the nonlinear wave equation show that the steady-state self-trapping of optical beams in molecular fluids exhibits new characteristics when the intensity-dependent index (orientational Kerr effect) begins to saturate. The power dependence of the beam diameter and the radial electric field distribution are examined. Beam diameters less than the wavelength of light are predicted for CS2 in the saturation regime.
ON THE ORIGIN OF THE WATER-VAPOR LASER LINES
Authors: Hartmann B. , Kleman B.
Published: January 2004

It is suggested that a main part of the water-vapor laser spectrum consists of transitions in the interacting 2v2, v3, and v1 states of H2O. The considered transitions are essentially of a pure rotation nature. Tentative assignments are made for 19 of the previously known laser lines.
IDENTIFICATION OF WATER-VAPOR LASER LINES
Authors: Benedict W. S.
Published: January 2004

Twenty five laser lines in water vapor are identified as transitions between known vibration-rotation levels. The mechanism is discussed: The initiating factor is a weak perturbation involving close resonance between levels of the bending overtone and the stretching fundamentals. Three resonances account for most of the strongest lines: 020, 550 ↔ 100, 514, at 4050 cm−1, 020, 661 ↔ 001, 633, at 4408 cm−1, and 020, 844 ↔ 100, 808 at 4387 cm−1 above the zero level. The 2527952.8 MHz line is assigned to 001, 642 → 020, 661.
MOLECULAR LEVEL PARAMETERS AND PROPOSED IDENTIFICATIONS FOR THE CW WATER-VAPOR LASER
Authors: Pollack M. A. , Tomlinson W. J.
Published: January 2004

Measurements of |ΔJ|, effective magnetic moments, and natural linewidths were made for most of the CW lines in H2O and D2O lasers. Using these results, previous results on couplings between the various CW lines, and published experimental data on the energy levels of H2O, identifications have been proposed for most of the CW lines as vibrational-rotational and pure rotational transitions in the J = 5 and J = 6 levels of the (100), (020), and (001) vibrational states of H2O.
VARIABLE TIME COMPRESSION, EXPANSION, AND REVERSAL OF RF SIGNALS BY LASER-ACOUSTIC TECHNIQUES
Authors: Brienza M. J.
Published: January 2004

Continuously variable time compression, expansion, and inversion, with the corresponding changes in frequency, of rf signals in the range of 10 to 100 MHz, are described. By using a simple optical heterodyning technique and high-speed scanning of a laser beam, an rf signal, ``stored'' as an acoustic signal in a quartz bar, can be processed or ``read out'' in a variety of ways. Although present equipment has limited the amount of processing and frequency range of the signals that can be handled, it is felt that input signal frequencies are restricted only by the acoustic properties of the delay medium and the output frequencies will be limited by the response of the photodetector.
CONTROLLED GENERATION OF INTENSE LIGHT PULSES IN REVERSE-PUMPED RAMAN LASERS
Authors: Culver W. H. , Vanderslice J. T. A. , Townsend V. W. T.
Published: January 2004

Narrow pulses have been generated in a reverse-pumped Raman laser containing H2. The output from a Q-switched ruby laser was focused into a H2 cell and converted into pulses with halfwidths of 3 × 10−10 sec at 9755 Å.
GENERATION OF HIGH-REPETITION-RATE OPTICAL PULSES BY A He–Ne LASER
Authors: Hirano Junzo , Kimura Tatsuya
Published: January 2004

Two methods to obtain higher multiple bit rate optical pulses from a laser are described, namely a mode-quenching method and a FM perturbation method. Optical pulses up to 600 Mbit/sec were experimentally obtained with a He–Ne laser. A tentative explanation of the occurrence of multiple bit pulses in the second method without mode quenching is given.
RESISTANCE MONITORING AND EFFECTS OF NONADHESION DURING ELECTROMIGRATION IN ALUMINUM FILMS
Authors: Rosenberg R. , Berenbaum L.
Published: January 2004

Resistance monitoring has been used to follow structural changes during electromigration in aluminum films. Two stages of migration were found, the first corresponding to gross mass transport, the second to void growth and stripe failure. An activation energy for the first stage was determined to be 0.5–0.6 eV from change-in-rate, change-in-temperature tests, indicating boundary diffusion. Transmission electron microscopy showed voids existing in areas of thinned aluminum. Corollary work on aluminum stripes on NaCl substrates showed nonadhesion to be a strong contributor to void formation, suggesting the possibility that the thinned regions were caused by hot spots at sites of nonadhesion.
STIMULATED EMISSION FROM 19 POLYMETHINE DYES-LASER ACTION OVER THE CONTINUOUS RANGE 710–1060 mμ
Authors: Miyazoe Yasushi , Maeda Mitsuo
Published: January 2004

Stimulated emission from 19 polymethine dyes pumped by a Q-switched ruby laser is reported in this Letter. High power laser emission (>1 MW) has been obtained over the whole wavelength range from 710 mμ to 1060 mμ.
RELATIONSHIP BETWEEN LINEAR AND QUADRATIC ELECTRO-OPTIC COEFFICIENTS IN LiNbO3, LiTaO3, AND OTHER OXYGEN-OCTAHEDRA FERROELECTRICS BASED ON DIRECT MEASUREMENT OF SPONTANEOUS POLARIZATION
Authors: Wemple S. H. , DiDomenico M. , Camlibel I.
Published: January 2004

The spontaneous polarizations in LiNbO3, LiTaO3, and Ba2NaNb5O15 have been measured directly at room temperature by a field reversal method and found to be Ps (LiNbO3) = 0.71 C/m2, Ps (LiTaO3) = 0.50 C/m2, and Ps (Ba2NaNb5O15) = 0.40 C/m2. Using these values we show that the linear electro-optic effect in these materials is related fundamentally to a biased quadratic effect associated with each BO6 octahedron. Based on this result, predictions are made of the spontaneous polarization in other oxygen-octahedra ferroelectrics.
THE EFFECT OF EXPANSION MISMATCH ON TEMPERATURE COEFFICIENT OF RESISTANCE OF THIN FILMS
Authors: Hall P. M.
Published: January 2004

The temperature coefficient of resistance of a thin-film resistor depends on the mismatch in the thermal expansion coefficient between the film and its substrate. This Letter presents a calculation of this effect and shows that the effect can be quite significant for typical thin films.
THIRD-ORDER ELASTIC CONSTANTS OF POLYCRYSTALLINE MEDIA
Authors: Juretschke H. J.
Published: January 2004

The three linear invariants associated with the third-order elastic coefficients are derived explicitly, and are used to relate the elastic parameters of a single crystal of arbitrary symmetry to those of a polycrystalline quasi-isotropic aggregate of the same material.
TIME-DEPENDENT ELECTRICAL CONDUCTION IN RUTILE SINGLE CRYSTALS
Authors: Van Ruyven L. J. , Chase J. D.
Published: January 2004

TiO2 single crystals were grown in the absence of hydrogen, using an induction plasma torch. The electrical conductivity of these crystals does not vary in time under the application of an electric field. To explain the conductivity creep in conventionally grown TiO2 single crystals, a mechanism is proposed based on iron-hydrogen impurity complexes which dissociate under the application of a voltage and can be restored by heating the crystal to 800°C.
CURRENT FILAMENTS IN AVALANCHING PIN DIODES
Authors: Muller M. W.
Published: January 2004

It is predicted that stable current filaments can be formed in an avalanching pin structure. The current density in a filament and its radius are determined by a dynamic equilibrium between carrier production by impact ionization and loss of carriers by diffusion.