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The microwave spectra of adamantan-1-ol and [2H1]adamantan-1-ol have been observed in the frequency range 8–40 GHz at temperatures of 340–350 K. The spectra consist of strong series of µa R-branch bands and in the case of adamantan-1-ol a weaker series of µb Q-branch bands. The separation of the µb Q-branch bands is almost twice that expected for a rigid rotor. An analysis using the internal axis method to treat the internal rotation of the hydroxy group and which assumes the molecule to be a symmetric rotor gives the approximate formula, v=(A–text-decoration:overlineB+w)(2K+ 1), for the observed µb Q-branch bands. The parameter w arises from the internal rotation part of the Hamiltonian. The barrier to internal rotation in adamantan-1-ol is estimated to be V3= 4.9 (4) kJ mol–1[410 (30) cm–1]. The error in V3 arises largely from the uncertainty in the moment of inertia of the hydroxy group about the internal rotation axis.

Apparent enzyme kinetics were determined for pulmonary angiotensin-converting enzyme (ACE) as a function of postnatal development and alveolar hypoxia in intact conscious lambs (9 newborn and 7 sheep, 8–23 wk). We injected into the right atrium a mixture of indocyanine green and 3H-labeled benzoyl-phenylalanyl-alanyl-proline (BPAP), a synthetic substrate for ACE, and sampled blood from the aorta at 1-s intervals. From this, we quantified the %BPAP metabolism during a single pass through the lungs by use of indicator-dilution techniques. By adding unlabeled BPAP to the injectate, combining outflow data from two to three measurements, and applying a nonlinear model of pulmonary metabolism (J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 51:405–414, 1981), we could determine 1) apparent maximum velocity (Vmax); 2) concentration at which velocity was one-half Vmax (Km); and 3) alpha, a measure of perfusion heterogeneity. All animals were studied during normoxia and while breathing 10% O2 for at least 15 min. Seven of the newborn lambs were studied 1 wk later. Km in the newborn was 15 +/- 3 microM and did not change significantly with age or hypoxia. Vmax increased markedly with development (newborn: 14 +/- 2 nmol X s-1 X g dry lung-1; sheep: 38 +/- 5 nmol X s-1 X g dry lung-1; P less than 0.01). Alveolar hypoxia significantly decreased Vmax in the newborn only (P less than 0.05); there was no significant change in Vmax in the same animal studied 1 wk later or in the older group.(ABSTRACT TRUNCATED AT 250 WORDS)

A reinvestigation of the microwave spectrum of N-methyl-p-fluoroaniline shows this molecule to have low lying excited vibrational states associated with the inversion and torsion of the HNCH3 group similar to N-methylaniline. The experimental data indicate a greater tendency towards a planar configuration at the nitrogen atom and a lower barrier to inversion compared to p-fluoroaniline.

Ethanol (2 g/kg) reduces the time spent in social interaction and increases locomotor activity of pairs of NIH Swiss mice. This study examined whether two benzodiazepine receptor inverse agonists, RO 15-4513 (3 mg/kg) and FG 7142 (30 mg/kg) are able to reverse these effects. Neither drug alone altered social behavior, but both significantly attenuated the effect of ethanol on social interaction. They did not affect the ethanol-induced increase in motor activity. Benzodiazepine receptor inverse agonists thus appear capable of antagonizing some, but not all of the behavioral effects of ethanol in this paradigm.

A series of experiments was performed to examine the effects of two benzodiazepine antagonists, flumazenil and ZK 93426, on the behavioral changes caused by ethanol (2 g/kg) in a holeboard test. The interaction between ethanol and low doses of diazepam (0.2 and 0.5 mg/kg) was also investigated. Both flumazenil and ZK 93426 reversed the reduction in exploration caused by ethanol, but tended to increase exploration when administered alone. In contrast, diazepam, which also increased exploration alone, tended to enhance the reduction in exploration caused by ethanol. Diazepam reduced the motor stimulant action of ethanol. The partial reversal by the two antagonists of the reduction in exploration caused by ethanol was not due to alterations in blood ethanol concentrations but may have resulted from their intrinsic exploration-increasing effects or an antagonism of an endogenous ligand for central benzodiazepine receptors.

The quadratic force field of diborane has been computed using the force method and an STO 4—31 G orbital basis.

The effects of three quinoline derivatives, PK 8165 (7.5 mg/kg), PK 9084 (7.5 mg/kg) and CGS 8216 (1 and 10 mg/kg), alone and in combination with chlordiazepoxide (5 mg/kg), were investigated in the social interaction test of anxiety. PK 8165 had no effect on social interaction but both PK 8165 and PK 9084 in combination with chlordiazepoxide produced sedation. PK 9084 exhibited a partial anxiolytic profile reflected by a drug × light interaction in the familiar test conditions. CGS 8216 (1 mg/kg) showed no significant effects on social interaction, but did counteract the sedative effect of chlordiazepoxide. The 10 mg/kg dose of 8216 reduced social interaction between pairs of animals in familiar test conditions which is indicative of an anxiogenic effect. These intrinsic anxiogenic properties of CGS 8216 demonstrate that if cannot be considered an inert benzodiazepine antagonist.

Treatment with 5HT reuptake inhibitors has been shown to attenuate ethanol consumption in both animals and humans. These experiments investigate in mice the interactions of the 5HT reuptake inhibitors fluoxetine, citalopram and fluvoxamine and the NA uptake inhibitor desipramine with ethanol in the holeboard test and the elevated plusmaze test of anxiety. Ethanol (2.4 g/kg) increased activity both in the holeboard and on the plusmaze, decreased both the number and duration of head-dips in the holeboard, and increased both the percentage time and percentage entries on to the open-arm of the plusmaze (reflecting its anxiolytic properties). On their own, the selective 5HT uptake inhibitors fluoxetine, fluvoxamine, and citalopram and the NA uptake inhibitor desipramine (10-20 mg/kg) did not significantly alter any of the behavioral measures. The only consistent interaction was seen with fluoxetine which reduced ethanol's anxiolytic effects at the 20 mg/kg dose without altering ethanol's effects on exploration or locomotion. The results suggest that the attenuation of ethanol's anxiolytic properties by fluoxetine may not be serotonin related since other 5HT reuptake inhibitors did not show this effect at the doses used.

The intrinsic effects of the benzodiazepine receptor ligand beta-CMC (3-(methoxycarbonyl)-amino-beta-carboline) and its interaction with the anticonvulsant and sedative effects of diazepam were assessed. beta-CMC (100 mg/kg i.p.) significantly elevated seizure threshold to bicuculline. beta-CMC (10 mg/kg) failed to alter the anticonvulsant action of diazepam (5 mg/kg i.p.), but significantly attenuated diazepam's sedative effect. A higher dose of beta-CMC (40 mg/kg) did attenuate diazepam's anticonvulsant action. The data suggest that beta-CMC is a partial agonist at benzodiazepine receptors.

It has recently been claimed that RO 15-4513 selectively opposes some of the behavioral actions of ethanol. Our studies on the intrinsic effects of this compound have shown it to be proconvulsant and to reduce exploratory behavior in mice. In these respects RO 15-4513 resembles a benzodiazepine receptor partial inverse agonist. Such intrinsic actions may well explain its alcohol-anatagonizing properties, and argue against its potential in humans. In addition to partially reversing the effects of ethanol, RO 15-4513 also partially reverses the behavioral effect of a barbiturate and completely reverses the effects of a benzodiazepine.

The microwave spectrum of acetaldehyde cyanohydrin shows two series of μ a R branch transitions of almost equal intensity which are accompanied by similar patterns of vibrational satellites. The most probable explanation of these two series of lines consistent with the expected conformational behaviour of acetaldehyde cyanohydrin is that they belong to the two non-equivalent rotamers in which the hydroxyl group is gauche to the cyanide group.

Microwave spectra of the normal and amine-deuterated isotopic species of N -methyl-aniline in the ground and some low-lying excited vibrational states have been observed. The inertial defect indicates that the dihedral angle of the N-CH 3 , bond with respect to the ring plane is somewhat less than that for the N—H bonds in aniline. The position of the amino-hydrogen atom is very poorly determined by the isotopic substitution method because of large zero-point effects. The excited vibrational states are consistent with a double-minimum potential for the inversion of the HNCH 3 group and there is some evidence for a lower barrier than in aniline. The excited states of the HNCH 3 torsion indicate a barrier in the range 8 2 −1 to the internal rotation of this group. No splitting of the ground-state lines attributable to the torsion of the methyl group has been observed, which implies a barrier of V 3 > 8 kJ mol −1 .

The microwave spectrum of N,N -dimethyl-4-aminopyridine has been observed in the temperature range 320–350 K. Effects due to the inversion and torsion of the NMe 2 group have been observed. The results show that the barrier to inversion and degree of non planarity are somewhat lower than in N,N -dimethylaniline. Some details of the computer controlled system used to obtain low resolution microwave spectra are given.

The microwave spectrum of 2-methyl-4,5-dihydrofuran has been observed in the frequency range 8–60 GHz. Spectra of the ground and first two states of the ring-bending vibration have been assigned. The variation of the rotational constants with vibrational state confirm the potential function derived by Carreira and Lord from the far-infrared spectrum. The molecule has a bent-ring conformation with a dihedral angle of ∼20°. A-E splittings due to the internal rotation of the methyl group have been observed and there is evidence for an interaction between the methyl torsion and the ring-puckering vibration. The electric dipole moment has been determined as μa = 0.47D, μb = 0.76D and μ = 0.90D.

RO 15–1788 (4–20 mg/kg), both alone and in combination with chlordiazepoxide (5 mg/kg), increased exploratory head-dipping in a holeboard above control levels. This intrinsic action of a benzodiazepine antagonist is not reversed, and is even augmented, by chlordiazepoxide. RO 15–1788 alone had no effect on locomotor activity, but antagonized the sedative effects of chlordiazepoxide. β-CCE (1 and 2 mg/kg) was without effect on locomotor activity, but the higher dose reduced head-dipping.

Ab initio computations have been performed on aniline and N -methylaniline using standard STO-3G orbitals to analyze the inversion barrier and the degree of non planarity in the two molecules. Our analysis indicates that the lowering of thei barrier in N -methyl-aniline with respect to aniline is due to hyperconjugation.

The behavioural effects of n-propyl beta-carboline-3-carboxylate (beta-CCP) were assessed in the social interaction test of anxiety and in the holeboard test of exploratory behaviour. n-Propyl beta-carboline-3-carboxylate (2 mg/kg) significantly reduced the time spent in social interaction without affecting locomotor activity, indicating an anxiogenic action. This reduction was not significantly reversed by chlordiazepoxide (3 mg/kg). In the holeboard, beta-CCP (4 mg/kg) reduced exploratory head-dipping and rearing; neither of these effects was significantly reversed by chlordiazepoxide (5 mg/kg). The actions of beta-CCP in these two tests are similar to those of the structurally-related compound ethyl beta-carboline-3-carboxylate.

Intravenous injection of ethyl β-carboline-3-carboxylate (β-CCE, 2 mg/kg) significantly reduced exploratory behaviour in a holeboard and 1 & 2 mg/kg markedly reduced the number of rears made. These effects were similar to those found with chlordiazepoxide (5 mg/kg). When they were given together the two drugs neither counteracted each other's effects, nor were their combined effects additive. We suggest that β-CCE and the benzodiazepines might both act at one class of benzodiazepine receptor, as agonists to produce the same behavioural effects. The results are also discussed with reference to other intrinsic actions of these compounds.

Direct l doublet transitions for the 01 1 0 state of 127 I 12 C 14 N and 127 I 13 C 14 N were observed between 4 and 25 GHz using a computer-controlled Stark modulation spectrometer. Values of the l doubling constants and the asymmetry parameters of the 127 I nuclear quadrupole coupling tensors were derived. Some details of the construction of the spectrometer are also given.

There is significant controversy about the role of bronchodilator therapy for wheezing in infants. A double-blind, randomized trial of subcutaneous epinephrine v normal saline was conducted in children

A qualitative description of the amnesia produced by the benzodiazepines in man is presented. The benzodiazepines exert their greatest effects in tests of long-term episodic memory in which they cause a dose-related impairment in the acquisition of new information, do not appear to affect retention and may facilitate retrieval. Benzodiazepines do not appear to impair semantic memory or the acquisition of skills. Although state-dependent learning may be observed with benzodiazepine treatment it is a small effect and cannot account for most of the observed impairments. The amnesia appears to be characteristic of all benzodiazepines and may be related to the sedative action of these compounds but evidence on the latter point is inconclusive. The importance of the amnesic action in a population of clinically anxious outpatients taking benzodiazepines over an extended period remains to be investigated. The benzodiazepines may provide the cognitive psychologist with a useful tool to investigate the mechanisms of normal memory.

The effects of picrotoxin (2 and 4 mg/kg) and of pentylenetetrazole (PTZ 5, 10 and 20 mg/kg) were examined in a social-interaction test of anxiety. Picrotoxin (2 mg/kg) caused a significant reduction in active social interaction, without a concomitant reduction in motor activity, indicating an anxiogenic action. Picrotoxin (4 mg/kg) and pentylenetrazole (20 mg/kg) reduced social interaction by more than 75% and motor activity by 40%. Although it is likely that the reduction in motor activity is secondary to the very low levels of social interaction, an unambiguous interpretation of an anxiogenic effect is not possible. Increased concentrations of corticosterone in plasma following administration of picrotoxin were consistent with the drug being anxiogenic. Chlordiazepoxide (5 mg/kg) significantly reversed the reductions in social interaction and locomotor activity following injection of picrotoxin (4 mg/kg) and PTZ (20 mg/kg).

The effect of postnatal development and acute alveolar hypoxia on pulmonary metabolic function was studied in conscious newborn lambs. Measurements of the ability of the lungs of these animals to metabolize [3H]benzoyl-L-phenyl-alanyl-L-alanyl-L-proline ([3H]BPAP; a synthetic substrate for angiotensin-converting enzyme, ACE) and to remove 5-hydroxy-[14C]tryptamine (5-[14C]HT) were made by modified indicator-dilution techniques during normoxic and hypoxic (fraction of inspired O2 = 0.10) conditions at 1 day, 1 wk, and 1 mo of age. Six additional sheep (8-23 wk old) were studied acutely as “adult” controls. BPAP metabolism in the 1-day-old group was 48 +/- 3% and increased slowly to 57 +/- 1% (P less than 0.05) at 1 mo of age and to 79 +/- 3% (P less than 0.01) by 23 wk of age. Pulmonary 5-[14C]HT removal was adultlike at birth (69 +/- 2%). Alveolar hypoxia significantly decreased BPAP only in the 1-day-old group (41 +/- 3%; P less than 0.05) and had no significant effect on 5-[14C]HT removal over the range of ages studied. These data demonstrate a selective and gradual postnatal development of pulmonary ACE which could be due to alterations in either the affinity or maximal capacity of pulmonary ACE, or increased endothelial cell surface area secondary to rapid growth of small blood vessels in this period. Alveolar hypoxia does not appear to closely regulate either ACE activity or 5-HT removal in conscious lambs greater than 1 day old when trace amounts of substrate are used.

The behavior of male mice from two BALB strains, the BALB/cJ strain and the BALB/cByJ strain, was examined with a social behavior test and a resident-intruder paradigm. Prior to testing, the animals were isolated for 0, 2, 5, or 10 days. In the social behavior test the pairs of BALB/cJ mice spent more time in active social interaction than pairs of BALB/cByJ mice, although the latter strain showed more locomotor activity. BALB/cJ mice isolated for 5–10 days, when tested in a familiar environment were more aggressive than mice from the BALB/cByJ strain. In the resident-intruder paradigm, in which a resident BALB mouse was confronted with an intruder NIH Swiss mouse, the BALB/cByJ mice showed more social investigation in their home cage towards the intruders, but there were no significant differences between the two strains in the amounts of aggressive behavior exhibited. The results of these experiments suggest that there are some differences in the social behavior of the genetically related BALB/cJ and BALB/cByJ mice. However, the differences appear subtle and paradigm-specific.

The microwave spectra of 1-adamantamine, [2H1]1-adamantamine and [2H2]1-adamantamine have been observed at room temperature in the frequency range 8–40 GHz. The spectra consist of both µa R-branch and µc Q-branch bands. The µa R-branch bands of the three isotopic species appear as doublets and this is attributed to the inversion of the amine group. A simple treatment of the internal rotation and inversion in which the molecule is regarded as a symmetric rotor shows that six series of ΔK=+1 µc Q-branch bands should be associated with the ground vibrational state. The band frequencies are shown to follow approximately the formulae v=a(2K+1) or v=a(2K+1)+b, where the constants a are the sum of the rotational constant A–text-decoration:overlineB and contributions from the internal motions. The formulae are verified experimentally for [2H2]1-adamantamine. The barrier to internal rotation in [2H2]1-adamantamine is determined to be V3= 9.0 (9) kJ mol–1[750 (70) cm–1] and the inversion splitting to be Δ°i= 1250 (30) MHz.

The microwave spectrum (41-10 GHz) and the infrared spectrum (4000-50 cm −1 ) of methyl thiolformate have been obtained and analyzed. The spectra are consistent with a single molecular conformation having a planar array of heavy atoms and with the alkyl group cis to the carbonyl group. The measured rotational constants are: A , 11042.22 MHz; B , 5118.27 MHz; C, 3562.03 MHz (κ = −0.5839). No internal rotation doublets were observed in the microwave spectrum for the ground vibrational state, which implies that the barrier hindering internal rotation of the methyl group is either much larger or much smaller than the corresponding value for methyl formate. If the former is true then a lower limit of 10.5 kJ mol −1 may be placed on the barrier height. The dipole moment of methyl thiolformate was measured using the Stark effect to be 1.58 ± 0.05 Debyes ( μ A = 1.52 D; μ B = 0.43 D) for the vapor, and for dilute solutions in benzene at 295 K the value of 1.6 ± 0.1 D was found from capacitance measurements. SCF computations using minimal basis sets of STO 3G atomic orbitals and extended basis sets of STO 4.31G atomic orbitals have been carried out for methyl thiolformate and methyl formate. Energy differences between rotational isomers and estimates of barrier heights are given together with the calculated dipole moments.

The microwave spectrum of 1,3,5-trithiane has been observed at a temperature of ca. 360 K in the frequency range 26–70 GHz. Only the spectrum of the symmetric top chair conformer is identified. Spectra of the ground vibrational state and some excited states involving the two lowest degenerate vibrations are assigned.

The characteristics of neutral-beam-heated ASDEX discharges exhibiting either low (L)- or high (H)-confinement are described. H-mode discharges, which are by now observed over a wide range of operating conditions, show a spontaneous improvement in particle and energy confinement after a short L-phase at the beginning of neutral injection. H-discharges yield high βp values comparable to the aspect ratio A (βp≤2.65~0.65 A). The most important parameter for transition to the H-mode seems to be a high edge electron temperature: Te values of -600 eV only a few centimeters inside the separatrix with radial gradients of ~300 eV/cm are measured. This requirement of high edge temperatures explains the lack of success in obtaining the H-regime in limiter discharges. Numerical simulation of the broad ne and Te profiles typical of H-mode plasmas indicates a reduction in electron thermal diffusivity by a factor of typically 2 over the entire plasma. H-mode energy confinement times are found to scale linearly with current, but to have little dependence on plasma density and absorbed beam power (PNI≤3.4MW). The confinement is degraded by a fast growing mode localized at the plasma edge that may be identified as a kink or tearing mode driven unstable by the high current densities at the edge.

Summary. In singleton births, maternal and fetal survival were poorest among primigravidae aged ≤15 years and also in the highly parous women aged ≥30 years. The young teenage girls constituted 6% of the survey population and 30% of the 174 maternal deaths, while the highly parous older women made up 10% of the survey population and 20% of the maternal deaths. The perinatal death rates per 1000 singleton deliveries were 180 for the young teenage girls, 150 for the highly parous groups had under 100 for the others. The major obstetric problems were dystocia due chiefly to contracted pelvis, anaemia, eclampsia, haemorrhage and infections. Emphasis is laid on the fact that the problems of these high-risk groups have their roots in the prevailing social attitudes which universal formal education stands the best chance of changing.

Some low-J μa R-branch lines of the E torsional substate of the ground vibrational state of methyl thiolformate were assigned. Calculations using the Internal Axis Method (IAM) and the Principal Axis Method (PAM) reproduce the observed line frequencies within a few MHz. The barrier to internal rotation of the methyl group is determined to be 1.78 ± 0.03 kJ mole−1.

The14N and35Cl nuclear quadrupole coupling constants of the14N32S35Cl isotopic species of thiazyl chloride have been determined from an analysis of the hyperfine structure of sixμa andμb transitions in the microwave spectrum as (in MHz)χaa(35CL) = −39.00(3),χbb(35CL) = 23.84(4),χaa(14N) = −1.42(6),χbb(14N) = −4.16(6).

When He+ and Ne+ are injected into an Ar carrier gas at 300K using a selected-ion flow-tube apparatus, Ar+ and Ar2+ are observed as reaction products. By observing the ratio of the sum of Ar+ and Ar2+ concentrations to that of Ne+ as a function of the Ar pressure it has been possible to show that the rate-determining step for this reaction is a two-body process (Ne++Ar) and to derive the charge-transfer rate coefficient.

The study of the dynamic stabilization of certain plasma confinement and fluid systems leads to equations of the form $$(X + 2A\cos (\omega t - \phi ))y(t) + \int_0^t {R(t - t')\dot y(t')dt' = 0} $$ , whereX andA are constants, ϕ an arbitrary phase andR(t) a singular response function. This equation is solved for all values ofA and the general stability properties of the system are discussed. General formulae are given which relate the perturbed spectrum of the system to the unperturbed system. For the case where the static system has well separated eigenfrequencies, a perturbation expansion is derived.

The microwave spectrum of N,N-dimethylaniline shows the presence of low vibrational states associated with the inversion of the NMe2 group and its torsion about the N-aryl bond. The μa R-branch lines of the ground and First inversion states show small deviations from rigid-rotor behaviour which are consistent with an energy difference of a few cm−1 between these states. The quantities Δ = Ia - Ib + Ic and Δc = Ia+Ib-Ic indicate values for the CH3NCH3 angle, α, of 114° and for the angle between the ring plane and that containing the two N-CH3 bonds, φ, of 27°. The barrier to inversion is in the range 1–3 kJ mol−1

We lowered cardiac output progressively in a controlled, stepwise fashion in conscious, unsedated lambs to determine the critical cardiac output or systemic oxygen delivery (the level at which oxygen consumption decreased abruptly). With the use of incremental inflation of a balloon-tipped catheter placed in the right atrium to lower cardiac output, we examined the response of oxygen consumption, systemic oxygen transport, fractional oxygen extraction, arterial lactate, and blood pressure. We studied lambs at 2 (n = 5), 4 (n = 5), and 8 wk (n = 6) of age and found that the 4-wk-old lambs reached critical values of cardiac output and systemic oxygen transport with the smallest proportional decreases from base-line values. Therefore, the 4-wk-old lambs were the least tolerant of acute decreases in cardiac output. We also found that fractional oxygen extraction was able to increase even after critical systemic oxygen transport was achieved. Furthermore, we found at every age that lactic acid accumulation began when the critical level of cardiac output was reached.

The present study examined the behavioral, neurochemical and endocrinological characteristics of aggressive, male alpha-mice. These mice inflict severe bite marks on other male mice in their cage, but are not attacked themselves. The characteristics of the alpha-mice were compared with those of submissive mice, and of control mice taken from cages in which no severe fighting was observed. The behavioral tests used were Porsolt's swim test of behavioral 'despair', a plusmaze test of anxiety, a holeboard test of exploration and locomotor activity, and a test of seizure threshold to bicuculline. The alpha-mice were found to be immobile in the swim test for a shorter time than the submissive and control mice, and the submissive mice for a longer time than the controls. In the holeboard, the alpha-mice spent less time making exploratory head-dips than the other mice. Submissive mice had elevated 5-HIAA levels in the hypothalamus, hippocampus and brainstem, and the alpha mice had reduced concentrations of dopamine in the brainstem. There were no significant differences in plasma corticosterone or testosterone concentrations between the groups. These findings indicate that in alpha-mice, a number of behavioral and neurochemical characteristics appear together with the unusually high aggressiveness towards cage-mates.

Two genetically related wheat lines growing in cabinets were given different temperatures during grain filling, and abscisic acid (ABA) was measured in whole grains by gas chromatography with an electron-capture detector. Three genetically related barley lines grown in the field were assayed for ABA content in endosperm and embryo fractions separately by radiommunoassay. Maximum grain growth rate and final weight per grain of the two wheat lines differed by 50–60% at low temperature and 30–40% at high temperature. During grain development two peaks in ABA level were observed at low temperature but only one at high temperature. At times when differences in grain growth rate between genotypes and between temperature treatments were large, the corresponding differences in ABA concentration were small. In barley, one line (Iabo 14) had 30% heavier grains than the other two (Onice and Opale). Endosperm ABA concentrations showed no clear differences between genotypes until grain filling was nearly complete. Embryo ABA levels were up to 10-times greater than those in the endosperm, with Opale having significantly less ABA in the embryo than the other two cultivars. Our experiments did not provide evidence for a causal relationship between ABA levels during grain filling and grain growth rate or final weight.

The interaction between isolation and the response to ethanol was investigated with a social behavior test and a loss of righting reflex paradigm. The time a pair of mice spent in active social interaction, aggressive behavior, and avoidance-irritability showed an isolation-related increase, while locomotor activity was not affected by 0-10 days of isolation. Ethanol (0.8 g/kg) reduced the social interaction time in mice isolated for 10 days and 2.0 g/kg ethanol reduced it in all groups. Ethanol induced a locomotor stimulatory effect both in group-housed and isolated animals. An aggression-inducing effect of 0.8 g/kg ethanol was observed only in mice isolated for 5 days, while mice isolated for 10 days reduced their aggressive behavior after this dose of ethanol. The loss of righting reflex after 3.5 g/kg ethanol did not appear to vary with isolation. The results suggest that isolation alters some effects of ethanol qualitatively (e.g., its effects on aggressive behavior) but leaves other effects (e.g., its locomotor stimulant and hypnotic effects) unchanged.

The microwave spectrum of 3-cyclohexen-1-one has been observed in the frequency range 18–40 GHz and transitions for the ground and 19 excited vibrational states have been assigned. Relative intensity measurements give the frequency of the two lowest vibrations as 74 and 147 cm−1. The molecule has a nonplanar ring and the molecular structure obtained from a molecular mechanics computation gives rotational constants in reasonable agreement with those obtained from the spectra.

The effects of three drugs, chosen for their differential effects on directed exploration and locomotion (ethanol, caffeine, and FG 7142), were examined on the locomotor activity of mice in a holeboard apparatus containing either a solid floor or one with four holes in it. The dose-related effect of all three drugs on locomotor activity was not changed by the presence of the holes, although activity was slightly higher when a solid floor was used. The results indicated that the two measures can vary independently and that the directed exploration component (head-dipping) of the holeboard test does not significantly influence the locomotor activity component.

Rapid and sensitive methods are described for determining lorazepam and for determining chlordiazepoxide and its metabolites in brain tissue of the rat. Lorazepam was determined by means of solvent extraction and electron-capture gas—liquid chromatography and concentrations as low as 5 ng/g tissue could be measured. High-performance liquid chromatography with UV detection was used to determine chlordiazepoxide and its metabolites and was sensitive to 0.1 μg/g tissue. The methods were used to investigate the brain and plasma pharmacokinetics of these compounds in animals that had been chronically treated with lorazepam or chlordiazepoxide. In both experiments brain and plasma levels of all compounds assayed were found to correlate highly.

Ro 15-4513 (1.5 mg/kg) decreased the exploratory activity of mice in a holeboard test. This effect was reversed by diazepam (1 mg/kg), ethanol (1 g/kg) and sodium pentobarbital (15 mg/kg). Higher doses of these three agents reduced the number of exploratory head-dips, and Ro 15-4513 antagonised these effects. These observations are consistent with the suggestion that Ro 15-4513 is a partial inverse agonist at benzodiazepine receptors and acts by reducing the efficacy of GABA. Ro 15-4513's interaction with ethanol in the holeboard closely resembled its interaction with the barbiturate.

The conformation and ring inversion in ethylene carbonate have been investigated using microwave spectroscopy and ab initio computations. The vibrational satellite spectra of the normal isotopic species of ethylene carbonate and the rotational constants of Backvall et al.(Tetrahedron Lett. 1980, 21, 4985) for cis- and trans-[1,2-2H2]ethylene carbonate show the molecule to have a twisted C2 equilibrium conformation. The vibrational satellite spectra have been analysed in terms of independent ring-bending and twisting vibration. A potential function for the twisting vibration derived from the variation of the rotational constants with vibrational state, and vibrational energy separations obtained from relative intensities and Coriolis perturbations give an equilibrium twist angle of 19° and a barrier to ring inversion of 2.8 kJ mol–1. The twist angle has also been obtained from inertial data, and a value of 15° is obtained using two methods of calculation. Ab initio computations of the ring-puckering potential-energy surface have been made using STO-3G and STO-3-21 G orbitals and complete geometry optimization. The STO-3G computations predict a planar C2ν equilibrium geometry, but with the twisting vibration being lower in frequency and more anharmonic than the bending vibration. The STO-3-21G computations predict a C2 conformation with an equilibrium twist angle of 14° and barrier to inversion through the planar ring conformation of 1.1 kJ mol–1. The computed barrier to ring inversion by pseudorotation is 14.3 kJ mol–1.

Non-empirical calculations of the electric dipole moments and nuclear quadrupole coupling constants of the isoelectronic series of molecules FCl, HOCl, NH2Cl and CH3Cl have been made and compared with the experimental results obtained using microwave spectroscopy. The trends in the electrical properties in the series of molecules have been interpreted using a localised molecular orbital picture. The application of the Townes-Dailey theory to the nuclear quadrupole coupling constants in these molecules is discussed. The barrier to the inversion of the amine group in monochloroamine has been calculated and the origin of the barrier is discussed.

The stability of a non-conducting, compressible fluid (gas) flowing across the surface of incompressible conducting fluid (liquid) is discussed. Finite resistivity and Hall current are included in the hydromagnetic equations, together with surface tension. Both subsonic and supersonic flows are treated and some new instabilities are found, together with modifications to real and oscillatory modes obtained in earlier treatments.