Sociodramatic play: Social class effects in integrated preschool classrooms

In previous studies, social class differences in children's sociodramatic play were studied in socially homogeneous, segregated schools. However, social class differences in play behavior were attributed to the abilities or interests of the children rather than to the situation in which they were observed. In the present study, sociodramatic play was observed in middle and lower class children attending the same preschool classrooms. In accord with previous studies, middle class children engaged in a higher level of play than did lower class children. Analyses of individual play components indicated that although middle class children verbalized more frequently, the quality of the language used by the two groups did not differ. Age differences were also significant. With age, play roles became more socially coordinated, the duration of play episodes increased and language became more complex. But social class groups did not differ on these measures. The implications of these results for the developmental lag hypothesis, other explanations of social class differences and classroom strategies are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24477/1/0000752.pd

Genetic variation within GRIN2B in adolescents with alcohol use disorder may be associated with larger left posterior cingulate cortex volume.

OBJECTIVE: Brain structure differences and adolescent alcohol dependence both show substantial heritability. However, exactly which genes are responsible for brain volume variation in adolescents with substance abuse disorders are currently unknown. The aim of this investigation was to determine whether genetic variants previously implicated in psychiatric disorders are associated with variation in brain volume in adolescents with alcohol use disorder (AUD). METHODS: The cohort consisted of 58 adolescents with DSM-IV AUD and 58 age and gender-matched controls of mixed ancestry ethnicity. An Illumina Infinium iSelect custom 6000 bead chip was used to genotype 5348 single nucleotide polymorphisms (SNPs) in 378 candidate genes. Magnetic resonance images were acquired and volumes of global and regional structures were estimated using voxel-based morphometry. To determine whether any of the genetic variants were associated with brain volume, association analysis was conducted using linear regression in Plink. RESULTS: From the exploratory analysis, the GRIN2B SNP rs219927 was associated with brain volume in the left posterior cingulate cortex (p<0.05), whereby having a G-allele was associated with a bigger volume. CONCLUSION: The GRIN2B gene is involved in glutamatergic signalling and may be associated with developmental differences in AUD in brain regions such as the posterior cingulate cortex. Such differences may play a role in risk for AUD, and deserve more detailed investigation

Intuiting a Monsoonal Ethnography in Three Bay of Bengal Cities

This visual essay offers an exploration of monsoonal materiality and agency in the urban environments of three cities situated around the Bay of Bengal: Chennai, Dhaka and Yangon. The text and images emerge from a research project exploring intersections between changing monsoon climates and rapid urbanisation in South Asia. Multi-modal, more-than-human ethnography has been employed during the course of research to explore how the lively materiality of the monsoon is entangled within urban lived environments. The essay outlines the process of intuiting a monsoonal ethnography and conveys the power of immersive field experience. By collecting and curating an assemblage of visual material and fieldnotes, this piece seeks to evoke the materiality and agency of the monsoon, itself a complex assemblage that manifests in different ways in different places. The juxtaposition of image and text conveys the generative and multifaceted agency of the monsoon and the urban environments it becomes enmeshed within

Universal criterion for the breakup of invariant tori in dissipative systems

The transition from quasiperiodicity to chaos is studied in a two-dimensional dissipative map with the inverse golden mean rotation number. On the basis of a decimation scheme, it is argued that the (minimal) slope of the critical iterated circle map is proportional to the effective Jacobian determinant. Approaching the zero-Jacobian-determinant limit, the factor of proportion becomes a universal constant. Numerical investigation on the dissipative standard map suggests that this universal number could become observable in experiments. The decimation technique introduced in this paper is readily applicable also to the discrete quasiperiodic Schrodinger equation.Comment: 13 page

Verified and potential pathogens of predatory mites (Acari: Phytoseiidae)

Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator¿prey interactions. Pathogen-free phytoseiid mites are important to obtain high efficacy in biological pest control and to get reliable data in mite research, as pathogens may affect the performance of their host or alter their reproduction and behaviour. Potential and verified pathogens have been reported for phytoseiid mites during the past 25 years. The present review provides an overview, including potential pathogens with unknown host effects (17 reports), endosymbiotic Wolbachia (seven reports), other bacteria (including Cardinium and Spiroplasma) (four reports), cases of unidentified diseases (three reports) and cases of verified pathogens (six reports). From the latter group four reports refer to Microsporidia, one to a fungus and one to a bacterium. Only five entities have been studied in detail, including Wolbachia infecting seven predatory mite species, other endosymbiotic bacteria infecting Metaseiulus (Galendromus, Typhlodromus) occidentalis (Nesbitt), the bacterium Acaricomes phytoseiuli infecting Phytoseiulus persimilis Athias-Henriot, the microsporidium Microsporidium phytoseiuli infecting P. persimilis and the microsporidium Oligosproridium occidentalis infecting M. occidentalis. In four cases (Wolbachia, A. phytoseiuli, M. phytoseiuli and O. occidentalis) an infection may be connected with fitness costs of the host. Moreover, infection is not always readily visible as no obvious gross symptoms are present. Monitoring of these entities on a routine and continuous basis should therefore get more attention, especially in commercial mass-production. Special attention should be paid to field-collected mites before introduction into the laboratory or mass rearing, and to mites that are exchanged among rearing facilities. However, at present general pathogen monitoring is not yet practical as effects of many entities are unknown. More research effort is needed concerning verified and potential pathogens of commercially reared arthropods and those used as model organisms in research

Re-evaluating the factor structure of the self-assessed wisdom scale (saws)

Background. Although wisdom is a desirable developmental goal, researchers often lack valid and reliable construct measures. Webster’s (2007) popular 40-item five factor SAWS structure has had mixed support in the literature. We tested this factor structure, and age group equivalencies. We also examined whether the SAWS Openness dimension is a wisdom precursor, as proposed by other models of wisdom. Methods. Data from 709 respondents were randomly split into two. We performed confirmatory factor analysis (CFA) on Sample 1. If the model did not fit the data, then exploratory factor analysis (EFA) on Sample 2 would offer an alternative model that could be confirmed on Sample 1. Structural equation models analysed Openness as a SAWS antecedent and a wisdom component. Multigroup CFA tested invariance across age groups. Results. The SAWS failed to replicate in the initial CFA. We extracted a 12-item four factor EFA solution, which excluded Humour factor. Openness as a wisdom component was a better model than as antecedent. Implications. The 12-item four factor model clarifies the key components of the SAWS and can be used across the adult lifespan as different age groups are invariant. We suggest Openness is better understood as a component of the SAWS

Large mass dileptons from the passage of jets through quark gluon plasma

We calculate the emission of large mass dileptons originating from the annihilation of quark jets passing through quark gluon plasma. Considering central collisions of heavy nuclei at SPS, RHIC and LHC energies, we find that the yield due to the jet-plasma interaction gets progressively larger as the collision energy increases. We find it to be negligible at SPS energies, of the order of the Drell-Yan contribution and much larger than the normal thermal yield at RHIC energies and up to a factor of ten larger than the Drell-Yan contribution at LHC energies. An observation of this new dilepton source would confirm the occurrence of jet-plasma interactions and of conditions suitable for jet-quenching to take place.Comment: 9 pages, 11 figures; references added, improved calculation, conclusions unchange

Counter-propagating radiative shock experiments on the Orion laser and the formation of radiative precursors

We present results from new experiments to study the dynamics of radiative shocks, reverse shocks and radiative precursors. Laser ablation of a solid piston by the Orion high-power laser at AWE Aldermaston UK was used to drive radiative shocks into a gas cell initially pressurised between $0.1$ and $1.0 \ bar with different noble gases. Shocks propagated at {80 \pm 10 \ km/s} and experienced strong radiative cooling resulting in post-shock compressions of { \times 25 \pm 2}. A combination of X-ray backlighting, optical self-emission streak imaging and interferometry (multi-frame and streak imaging) were used to simultaneously study both the shock front and the radiative precursor. These experiments present a new configuration to produce counter-propagating radiative shocks, allowing for the study of reverse shocks and providing a unique platform for numerical validation. In addition, the radiative shocks were able to expand freely into a large gas volume without being confined by the walls of the gas cell. This allows for 3-D effects of the shocks to be studied which, in principle, could lead to a more direct comparison to astrophysical phenomena. By maintaining a constant mass density between different gas fills the shocks evolved with similar hydrodynamics but the radiative precursor was found to extend significantly further in higher atomic number gases (\sim$$4$ times further in xenon than neon). Finally, 1-D and 2-D radiative-hydrodynamic simulations are presented showing good agreement with the experimental data.Comment: HEDLA 2016 conference proceeding