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Notes: Summary Direct administration of d-tubocurarine into the lateral cerebral ventricle of conscious rats produced decreased metabolism, cutaneous vasodilatation and hypothermia at ambient temperatures of 8–22°C. Also, pretreatment with d-tubocurarine antagonized the arecoline-induced hypothermia.

Notes: The dynamics of solvation of newly created charged species in dense dipolar liquids can proceed at a high speed with time constants often in the subpicosecond domain. The motion of the solvent molecules can be in the inertial limit at such short times. In this paper we present a microscopic study of the effects of inertial motion of solvent molecules on the solvation dynamics of a newly created ion in a model dipolar liquid. Interesting dynamical behavior emerges when the relative contribution of the translational modes in the wave-vector-dependent longitudinal relaxation time is significant. Especially, the theory predicts that the time correlation function of the solvation energy can become oscillatory in some limiting situations. In general, the dynamics becomes faster in the presence of the inertial contribution. We discuss the experimental situations where the inertial effects can be noticeable.

Notes: It was recently proposed that collective polarization excitations, called dipolarons in analogy with the plasmons in the Coulomb systems, can exist for a long duration in a dense dipolar liquid. In this article, we present a microscopic analysis of the properties of such collective excitations, both at small and at intermediate wave vectors. The theory predicts the existence of dipolarons at values of the relevant parameters which are in good agreement with the computer simulation of Pollock and Alder. However, the predicted range of the parameter values in which the "true'' dipolaronic behavior is significant are rather too small to be important in common dipolar liquids like water, acetonitrile or methyl iodide. We find that the microscopic structure, especially the local orientational correlations and also the translational modes of the liquid, play important roles in determining the nature and the lifetime of the dipolaronic modes. Especially, these modes are more likely to occur at intermediate wave numbers if the translational contribution to the polarization relaxation is significant. The consequences of these theoretical predictions in experimental studies are discussed.

Notes: Both the equilibrium and the dynamical aspects of solvation of a classical ion in a dense binary dipolar liquid are investigated by using a molecular theory. The theory properly includes the differing inter- and intramolecular correlations that are present in a binary mixture. As a result, the theory can explain several important aspects of the nonideality of equilibrium solvation energy (broadly known as preferential solvation) observed in experiments. We find that the nonideality of solvation depends strongly on both the molecular size and the magnitude of the dipole moment of the solvent molecules. The interactions among the solvent molecules play an important role in determining the extent of this nonideality. The dynamical calculations are based on a generalized Smoluchowski equation which has been used extensively for studies in one component liquid. For binary liquid, our study reveals rich and diverse behavior such as dependencies on the sizes, the transport coefficients and the polar properties of the components. The theory offers a detailed picture of the dependence of the solvation dynamics on the composition of the mixture. It is predicted that the dynamics of solvation in a binary liquid is, in general, nonexponential and that the details of the dynamics can be quite different from those in a one component liquid. In particular, the continuum model is found to be grossly inaccurate in describing the solvation dynamics in binary mixtures and rather extreme conditions are needed to recover the predictions of the continuum model which can be attributed to the nonideality of the solvation. The predicted results are used to study the dynamic solvent effects on the rate of an adiabatic electron transfer reaction in a binary liquid. The theoretical predictions are also compared with the available experimental results.

Notes: The relationship between the microscopic orientational relaxation time (τm) and the collective, macroscopic relaxation time (τM) of a dipolar liquid has been a subject of considerable interest. We examine this relation for the kinetic Ising model of Glauber, used recently by Skinner to describe dielectric relaxation in glassy polymers. In this model, exact solutions for both the same spin and the collective spin time correlation functions are possible. We find that these two correlation functions are entirely different from each other. The self spin correlation function is highly nonexponential, as pointed out by Glauber and by Skinner. But, the collective spin relaxation is single exponential, and the wave vector and frequency dependent dielectric function is of simple Debye form. The reason for this difference is discussed.

Notes: Measures of reading achievement and verbal ability have been shown to be heritable. Additionally, recent evidence has been suggestive of a major gene effect on reading disability and for problem reading in a sample of normal readers. We report on the etiology of individual differences in oral reading performance, the Slosson Oral Reading Test (SORT), for which biometrical analyses have not been reported in the literature previously. Oral reading performance was measured in a large population-based sample of twins of the Virginia Twin Study of Adolescent Behavioral Development. Biometrical analyses of the SORT suggested that, in both mates and females. 69% of the phenotypic variation was due to heritable influences and 13”v of the variation dm- to shared environmental effects. While the relative importance of genetic and environmental influences is equivalent for males and females, males showed greater phenotypic variability than females.

Notes: Little is known about the contribution of genetic and environmental factors to risk for juvenile psychopathology. The Virginia Twin Study of Adolescent Behavioral Development allows these contributions to be estimated. A population-based, unselected sample of 1412 Caucasian twin pairs aged 8–16 years was ascertained through Virginia schools. Assessment of the children involved semi-structured face-to-face interviews with both twins and both parents using the Child and Adolescent Psychiatric Assessment (CAPA). Self-report questionnaires were also completed by parents, children, and teachers. Measures assessed DSM-III-R symptoms of Attention Deficit Hyperactivity Disorder (ADHD), Conduct Disorder, Oppositional Defiant Disorder, Overanxious Disorder, Separation Anxiety, and Depressive Disorder. Factorially derived questionnaire scales were also extracted. Scores were normalized and standardized by age and sex. Maximum likelihood methods were used to estimate contributions of additive and nonadditive genetic effects, the shared and unique environment, and sibling imitation or contrast effects. Estimates were tested for heterogeneity over sexes. Generally, monozygotic (MZ) twins correlated more highly than dizygotic (DZ) twins, parental ratings more than child ratings, and questionnaire scales more highly than interviews. DZ correlations were very low for measures of ADHD and DZ variances were greater than MZ variances for these variables. Correlations sometimes differed between sexes but those for boy-girl pairs were usually similar to those for like-sex pairs. Most of the measures showed small to moderate additive genetic effects and moderate to large effects of the unique individual environment. Measures of ADHD and related constructs showed marked sibling contrast effects. Some measures of oppositional behavior and conduct disorder showed shared environmental effects. There were marked sex differences in the genetic contribution to separation anxiety, otherwise similar genetic effects appear to be expressed in boys and girls. Effects of rater biases on the genetic analysis are considered. The study supports a widespread influence of genetic factors on risk to adolescent psychopathology and suggests that the contribution of different types of social influence may vary consistently across domains of measurement.

Notes: We introduce an overlapping cohort sequential longitudinal study of behavioral development and psychopathology in a representative sample of 1412 pairs of twins aged 8 through 16 years. Multiple phenotypic assessments involve a full psychiatric interview with each child and each parent, and supplementary parental, teacher, and child interview material and questionnaires. For the first wave of assessments, the numbers of reported DSM-III-R symptoms of Major Depressive Disorder (MDD), Separation Anxiety Disorder (SAD), Overanxious Disorder (OAD), Oppositional Defiant Disorder (ODD), Conduct Disorder (CD), and Attention Deficit Hyperactivity Disorder (ADHD), assessed through interviews, confirm patterns of age and sex trends found in other epidemiological samples, but underscore their dependence on whether the child or the parent is the informant. Correlations across domains for symptoms reported by the same informant are often as large as correlations across informants for the same domain of symptoms. Factor analyses of these symptom counts, taking account of informant view and unreliability of assessment, show the high degree of correlation between SAD and OAD, between MDD and OAD, and between CD and ODD. ADHD symptoms are relatively independent of the other domains, but show moderate correlations with CD, ODD, and MDD. Factorially derived dimensional questionnaire scales, based on child, parental, and teacher reports, show patterns of relationship to symptom counts consistent with both convergent and discriminant validity as indices of liability to clinical symptoms. Across informants, questionnaire scales provide as good a prediction of symptoms as do clinical interviews. Multitrait-multimethod confirmatory factor analysis reveals the patterns of relationship between symptoms of psychiatric disorder in children taking due account of informant and unique sources of variance. Gender differences are consistent within the correlated clusters of ODD/CD and MDD/SAD/OAD, although there are disorder-specific age trends. There are large informant-specific influences on the reporting of symptoms in clinical interviews. Dimensional questionnaire scales provide a useful source of additional information. In subsequent analyses of genetic and environmental etiology of childhood psychopathology we must expect that results may differ by informant and method of assessment. Multivariate and developmental analyses that explore the sources of these differences will shed new light on the relationship between genetic and environmentally influenced vulnerability and the manifestation of psychopathology in specific circumstances.

Notes: : A 2.2-hectare potato (Solanum tuberosum L. cv Chieftain) field at Saint Leonard d'Aston, Quebec (lat. 72° 24′ 30″ long. 46° 5′ 30″) was instrumented to measure tile drain flow over two growing seasons, 1989 and 1990. The soil was a Sainte Jude sandy loam. Soil properties and nitrate concentrations in the drain flow were measured. The CREAMS (Chemicals, Runoff and rosion from agricultural Management systems) computer simulation model was validated for the study site. CREAMS underpredicted event percolation depths. However, total monthly percolation depths were close to observed values. CREAMS overpredicted event nitrate concentrations leached to tile drainage. There was a poor match between predicted and observed event nitrate concentrations in drain flow (coefficient of predictability, CPA= 104.95). Based on a sensitivity analysis, input parameters, representative of local conditions, were determined for the CREAMS hydrology and nutrient submodels.