Vicarious learning through capturing task‐directed discussions

The vicarious learner group has been developing a multimedia database system to promote and enhance the role of dialogue in learning. A specific interest, and the origin of the projects' collective name, is in the question of whether and how dialogue can be helpfully ‘reused’. What benefits can students gain from dialogue as observers, not just as participants? We describe our initial attempts to generate and capture educationally effective discourse exchanges amongst and between students and tutors. Problems encountered with available CMC discourse formats led to our development of a set of Task Directed Discussions (TDDs). A medium‐sized corpus of discourse exchanges was collected using the TDDs. A selection of nearly two hundred of these TDD exchanges formed the multimedia discourse database to the implemented prototype system, Dissemination. Initial results from a controlled experiment and evaluation of Dissemination are outline

Internal secretions of the female generative organs: with experimental enquiry into the secretions of the uterus and tubes in rabbits

My interest in the subject of the Internal Secretions, and particularly those of the generative organs in the female, has been aroused by the observation of clinical cases, after removal of ovaries, in which menstruation recurred, and also in a case in which, after double ovariotomy and sub-total hysterectomy, there was a regular and excessive discharge of blood from the lining of the cervix, which recurred with definite periodicity, and was unaffected by any drugs, until I tried corpora lutea. On looking up the literature of the subject, I came across Bond's paper, as also that of Blair Bell, dealing with the correlation of ovaries and womb, the views expressed being diametrically opposed. Bond also touched on the question of the saline secretion of the mucosa of the tubes and. womb, and I determined 'that as I had the opportunity to do some experimental work, that I would check some of his observations, particularly such as dealt with the ovarian influence on the changes and function of the uterine mueosa, with special reference to the secretion of the saline fluid. My observations will, I hope, form some small contribution, however slight, to our knowledge of the subject, which bears so intimately on operative gynecological treatment. The experiments are some of a series conducted at the Laboratory of the Royal College of Physicians, Edinburgh, between November 1910 and February 1913

Natural Four-Generation Mass Textures in MSSM Brane Worlds

A fourth generation of Standard Model (SM) fermions is usually considered unlikely due to constraints from direct searches, electroweak precision measurements, and perturbative unitarity. We show that fermion mass textures consistent with all constraints may be obtained naturally in a model with four generations constructed from intersecting D6 branes on a T^6/(Z_2 x Z_2) orientifold. The Yukawa matrices of the model are rank 2, so that only the third- and fourth-generation fermions obtain masses at the trilinear level. The first two generations obtain masses via higher-order couplings and are therefore naturally lighter. In addition, we find that the third and fourth generation automatically split in mass, but do not mix at leading order. Furthermore, the SM gauge couplings automatically unify at the string scale, and all the hidden-sector gauge groups become confining in the range 10^{13}--10^{16} GeV, so that the model becomes effectively a four-generation MSSM at low energies.Comment: Accepted for publication in Physical Review

Neural Correlates of Developmental Speech and Language Disorders: Evidence from Neuroimaging.

Disorders of speech and language arise out of a complex interaction of genetic, environmental, and neural factors. Little is understood about the neural bases of these disorders. Here we systematically reviewed neuroimaging findings in Speech disorders (SD) and Language disorders (LD) over the last five years (2008-2013; 10 articles). In participants with SD, structural and functional anomalies in the left supramarginal gyrus suggest a possible deficit in sensory feedback or integration. In LD, cortical and subcortical anomalies were reported in a widespread language network, with little consistency across studies except in the superior temporal gyri. In summary, both functional and structural anomalies are associated with LD and SD, including greater activity and volumes relative to controls. The variability in neuroimaging approach and heterogeneity within and across participant samples restricts our full understanding of the neurobiology of these conditions- reducing the potential for devising novel interventions targeted at the underlying pathology

A prospective longitudinal study of perceived infant outcomes at 18-24 months: Neural and psychological correlates of parental thoughts and actions assessed during the first month postpartum

The first postpartum months constitute a critical period for parents to establish an emotional bond with their infants. Neural responses to infant-related stimuli have been associated with parental sensitivity. However, the associations among these neural responses, parenting, and later infant outcomes for mothers and fathers are unknown. In the current longitudinal study, we investigated the relationships between parental thoughts/actions and neural activation in mothers and fathers in the neonatal period with infant outcomes at the toddler stage. At the first month postpartum, mothers (n=21) and fathers (n=19) underwent a neuroimaging session during which they listened to their own and unfamiliar baby’s cry. Parenting-related thoughts/behaviors were assessed by interview twice at the first month and 3-4 months postpartum and infants’ socioemotional outcomes were reported by mothers and fathers at 18-24 months postpartum. In mothers, higher levels of anxious thoughts/actions about parenting at the first month postpartum, but not at 3-4 months postpartum, were associated with infant’s low socioemotional competencies at 18-24 months. Anxious thoughts/actions were also associated with heightened responses in the motor cortex and reduced responses in the substantia nigra to own infant cry sounds. On the other hand, in fathers, higher levels of positive perception of being a parent at the first month postpartum, but not at 3-4 months postpartum, were associated with higher infant socioemotional competencies at 18-24 months. Positive thoughts were associated with heightened responses in the auditory cortex and caudate to own infant cry sounds. The current study provides evidence that parental thoughts are related to concurrent neural responses to their infants at the first month postpartum as well as their infant’s future socioemotional outcome at 18-24 months. Parent differences suggest that anxious thoughts in mothers and positive thoughts in fathers may be the targets for parenting-focused interventions very early postpartum

Corral systems for handling and sorting hogs (1993)

Construction of semi-confinement feeding floors for swine has increased in recent years. Available plans concentrate on design of the confinement area and feed handling. As producers expand, they need more efficient ways to sort, handle and load hogs. Additional planning is required to design smooth flow patterns for livestock handling into the basic production unit

The Effect of Truck Design on Pavement Performance

When work is done on some materials systems, their internal geometric states are altered in such a way that they have the potential to give back work when the force is removed and the system returns to its original configuration. This stored energy is called strain energy. Strain energy density (strain energy per unit volume) is a function of the Young\u27s modulus of elasticity and Poisson\u27s ratio and the nine strain (or stress) components; but it is independent of the coordinate system. Material properties are input into the Chevron N-layer computer program to calculate the strain components. Having calculated the strain energy density at a point, another quantity called work strain can be defined as the value of the strain corresponding to an uniaxial stress situation leading to the same strain energy density at the point. It can be used as the \u27\u27effective strain and is related to any single component of strain. Thus, pavement design systems based upon a single component of strain may be easily converted to a strain energy density basis. Configurations with loads distributed equally between the axles of an axle group were evaluated and damage factor relationships are reviewed. However, inspections of tandem axle suspensions on semitrailer trucks have shown that most tandem groups do not distribute the load equally to the axles. A theoretical investigation was made using pavement structures identical to those tested at the AASHO Road Test. The 1976 W-6 Table for Kentucky was used to obtain actual weight data. Preliminary analyses of tandem groups for 3S2 vehicles revealed a 40-percent increase in EAL over that calculated EAL assuming the total load on each tandem group had been uniformly distributed to the axles

Primary maternal preoccupation revisited: circuits, genes, and the crucial role of early life experience

Parental caregiving includes a set of highly conserved set of behaviors and mental states that may reflect both an individual’s genetic endowment and the early experience of being cared for as a child. This review first examines the mental and behavioral elements of early parental caregiving in humans. Second, we consider what is known of the neurobiological substrates of maternal behaviors in mammalian species including some limited human data. Third, we briefly review the evidence that specific genes encode proteins that are crucial for the development of the neural substrates that underlie specific features of maternal behavior. Fourth, we review the literature on the “programming” role of epigenetic factors in shaping subsequent maternal behavior. We conclude that there are critical developmental windows during which the genetically determined microcircuitry of key limbic-hypothalamic-midbrain structures are susceptible to early environmental influences and that these influences powerfully shape an individual’s responsivity to psychosocial stressors and their resiliency or vulnerability to various forms of human psychopathology later in life.South African Psychiatry Review - May 200