The Effects of Auditory Stimulation on Academic and Behavior Performance in Children With and Without Attention-Deficit/Hyperactivity Disorder

This study evaluated the relationship between noise and academic performance and behavior of children with ADHD (n = 15) and without ADHD (n = 18). Children completed math sheets under four noise conditions: no noise, standard classroom noise, classroom noise with verbalizations, and classroom noise with classical music. There were no differences in math performance between the two groups. Children with ADHD exhibited more problem behaviors than children without ADHD. Group-by-condition interactions were not significant. Significant effects were found for noise condition; children completed more math problems and had fewer inappropriate behaviors in the no-noise condition. However, there were significant order effects with children performing better on the initial task. The no-noise condition was always presented first; other conditions were randomized. Thus, it is impossible to determine if improved performance was due to decreased environmental stimulation or initial performance effects. Implications of these findings are discussed

Sleep Problems in Young Children With and Without Behavior Problems

There are numernus social, emotional, and behavioral problems toddlers and preschool children can exhibit. Some of the more common problems reported by parents of young children are daytime behavior problems and sleep disturbances. This study investigated sleep difficulties in toddler and preschool-age children with (n = 31) and without (n = 59) significant behavior problems. Furthermore, the current study investigated the relationship between sleep difficulties and other psychological constructs (i.e., maternal general stress, maternal depression, and parenting stress), which might be related to sleep and behavior problems. Mothers of clinically referred children with behavior problems and nonclinically referred children without behavior problems completed measures regarding their children\u27s sleep and behavior as well as their own general stress, parenting stress, and depressive symptomology. Overall, children with behavior problems showed significantly more sleep difficulties than children without behavior problems. Specifically, when compared to children without behavior problems, children with behavior problems took more time to initiate sleep, showed increased bedtime resistance, had more night wakings, and had shorter sleep durations. Additionally, the results showed that other factors (i.e., maternal depression, family stress, parent-child relationship stress) likely contribute to and/or maintain sleep disturbances in children. The findings from this study suggest a complex relationship between childhood sleep, daytime externalizing behaviors, and maternal health. Potential clinical implications of these findings and future directions for research are discussed

Differences in Response to Hypoxia in the Three-Spined Stickleback from Lotic and Lentic Localities: Dominance and an Anaerobic Metabolite

Dominance hierarchies of the three-spined stickleback Gasterosteus aculeatus from river and pond populations were subjected to hypoxia (20%, range±1%). Under hypoxia, the hierarchies were less stable in terms of rank position and tissue L-lactate was higher in river fish than pond fish under normoxia and hypoxia. Dominant fish gained mass under normoxia but lost mass under hypoxic conditions possibly due to them maintaining high levels of aggression

Self-similar impulsive capillary waves on a ligament

We study the short-time dynamics of a liquid ligament, held between two solid cylinders, when one is impulsively accelerated along its axis. A set of one-dimensional equations in the slender-slope approximation is used to describe the dynamics, including surface tension and viscous effects. An exact self-similar solution to the linearized equations is successfully compared to experiments made with millimetric ligaments. Another non-linear self-similar solution of the full set of equations is found numerically. Both the linear and non-linear solutions show that the axial depth at which the liquid is affected by the motion of the cylinder scales like $\sqrt{t}$. The non-linear solution presents the peculiar feature that there exists a maximum driving velocity $U^\star$ above which the solution disappears, a phenomenon probably related to the de-pinning of the contact line observed in experiments for large pulling velocities

Pain in farm animals

This review will address how we can measure pain in farm animals and discuss the major causes of acute pain and also chronically painful conditions, and finally make suggestions for future improvements. Pain is a relatively difficult concept to define since it comprises both a physiological sensory and a psychological or emotional component. Pain is the subjective interpretation of nerve impulses induced by a stimulus that is actually or potentially damaging to tissues. The sensation of pain is a response to a noxious stimulus and should elicit protective motor (e.g. withdrawal reflex, escape) and vegetative responses (e.g. cardiovascular responses, inflammation). Zimmerman (1986) also suggested that in animals a painful experience should result in learned avoidance and affect the animal’s behaviour including social behaviour. Therefore we can use behavioural and physiological criteria to determine whether an experience is painful to an animal. It is easier to assess pain in humans since we can tell each other how we are feeling. Many people are unwilling to accept that animals can feel pain since they believe that animals are not capable of having emotions that are similar to humans. The purpose of this review is not to debate this point but animal pain is possibly different to human pain, and can be defined as an “unpleasant sensory and emotional experience” (Bateson 1991). Pain is associated with suffering and distress and the treatment of animals in farm situations has been subject to increasing public concern. During production, farm animals are exposed to procedures which can lead to injury, disease and other noxious events and this will have negative consequences for the animal and on production (Table 1; Fraser and Duncan 1988; Bath 1998). Therefore it is vital for the animal’s wellbeing and for economic reasons that we measure and evaluate potentially painful situations in order to reduce suffering and financial losses. Esslemont (1990) estimated the impact of lameness caused by a sole ulcer to be between £227 and £297 per animal

Pain in farm animals

This review will address how we can measure pain in farm animals and discuss the major causes of acute pain and also chronically painful conditions, and finally make suggestions for future improvements. Pain is a relatively difficult concept to define since it comprises both a physiological sensory and a psychological or emotional component. Pain is the subjective interpretation of nerve impulses induced by a stimulus that is actually or potentially damaging to tissues. The sensation of pain is a response to a noxious stimulus and should elicit protective motor (e.g. withdrawal reflex, escape) and vegetative responses (e.g. cardiovascular responses, inflammation). Zimmerman (1986) also suggested that in animals a painful experience should result in learned avoidance and affect the animal’s behaviour including social behaviour. Therefore we can use behavioural and physiological criteria to determine whether an experience is painful to an animal. It is easier to assess pain in humans since we can tell each other how we are feeling. Many people are unwilling to accept that animals can feel pain since they believe that animals are not capable of having emotions that are similar to humans. The purpose of this review is not to debate this point but animal pain is possibly different to human pain, and can be defined as an “unpleasant sensory and emotional experience” (Bateson 1991). Pain is associated with suffering and distress and the treatment of animals in farm situations has been subject to increasing public concern. During production, farm animals are exposed to procedures which can lead to injury, disease and other noxious events and this will have negative consequences for the animal and on production (Table 1; Fraser and Duncan 1988; Bath 1998). Therefore it is vital for the animal’s wellbeing and for economic reasons that we measure and evaluate potentially painful situations in order to reduce suffering and financial losses. Esslemont (1990) estimated the impact of lameness caused by a sole ulcer to be between £227 and £297 per animal

Gaze aversion during social style interactions in autism spectrum disorder and Williams syndrome

During face-to-face interactions typically developing individuals use gaze aversion (GA), away from their questioner, when thinking. GA is also used when individuals with autism (ASD) and Williams syndrome (WS) are thinking during question-answer interactions. We investigated GA strategies during face-to-face social style interactions with familiar and unfamiliar interlocutors. Participants with WS and ASD used overall typical amounts/patterns of GA with all participants looking away most while thinking and remembering (in contrast to listening and speaking). However there were a couple of specific disorder related differences: participants with WS looked away less when thinking and interacting with unfamiliar interlocutors; in typical development and WS familiarity was associated with reduced gaze aversion, however no such difference was evident in ASD. Results inform typical/atypical social and cognitive phenotypes. We conclude that gaze aversion serves some common functions in typical and atypical development in terms of managing the cognitive and social load of interactions. There are some specific idiosyncracies associated with managing familiarity in ASD and WS with elevated sociability with unfamiliar others in WS and a lack of differentiation to interlocutor familiarity in ASD. Regardless of the familiarity of the interlocutor, GA is associated with thinking for typically developing as well as atypically developing groups. Social skills training must take this into account

Transversely Driven Charge Density Waves and Striped Phases of High-Tc_c Superconductors: The Current Effect Transistor

We show that a normal (single particle) current density $J_x$ {\em transverse} to the ordering wavevector $2k_F{\bf\hat{z}}$ of a charge density wave (CDW) has dramatic effects both above and {\em below} the CDW depinning transition. It exponentially (in $J_x$) enhances CDW correlations, and exponentially suppresses the longitudinal depinning field. The intermediate longitudinal I-V relation also changes, acquiring a {\em linear} regime. We propose a novel ``current effect transistor'' whose CDW channel is turned on by a transverse current. Our results also have important implications for the recently proposed ``striped phase'' of the high-T$_c$ superconductors.Comment: change of title and minor corrections, 4 RevTeX pgs, to appear in Phys. Rev. Lett., 81, 3711 (1998

Solution of the Percus-Yevick equation for hard discs

We solve the Percus-Yevick equation in two dimensions by reducing it to a set of simple integral equations. We numerically obtain both the pair correlation function and the equation of state for a hard disc fluid and find good agreement with available Monte-Carlo calculations. The present method of resolution may be generalized to any even dimension.Comment: 9 pages, 3 figure

Hard collinear gluon radiation and multiple scattering in a medium

The energy loss of hard jets produced in the Deep-Inelastic scattering (DIS) off a large nucleus is considered in the collinear limit. In particular, the single gluon emission cross section due to multiple scattering in the medium is calculated. Calculations are carried out in the higher-twist scheme, which is extended to include contributions from multiple transverse scatterings on both the produced quark and the radiated gluon. The leading length enhanced parts of these power suppressed contributions are resummed. Various interferences between such diagrams lead to the Landau-Pomeranchuk-Migdal (LPM) effect. We resum the corrections from an arbitrary number of scatterings and isolate the leading contributions which are suppressed by one extra power of the hard scale $Q^{2}$. All powers of the emitted gluon forward momentum fraction $y$ are retained. We compare our results with the previous calculation of single scattering per emission in the higher-twist scheme as well as with multiple scattering resummations in other schemes. It is found that the leading ($1/Q^2$) contribution to the double differential gluon production cross section, in this approach, is equivalent to that obtained from the single scattering calculation once the transverse momentum of the final quark is integrated out. We comment on the generalization of this formalism to Monte-Carlo routines.Comment: 30 pages, 7 figures, revtex4, typos correcte