1,382 research outputs found
Discourse patterns employing choral response in mathematics classrooms in seven countries
Choral response as a significant form of verbal response in mathematics classrooms in seven countries
Spoken mathematics as an instructional strategy: the public discourse of mathematics classrooms in different countries
Refugees, trauma and adversity-activated development
The nature of the refugee phenomenon is examined and the position of mental health professionals is located in relation to it. The various uses of the word 'trauma' are explored and its application to the refugee context is examined. It is proposed that refugees' response to adversity is not limited to being traumatized but includes resilience and Adversity-Activated Development (AAD). Particular emphasis is given to the distinction between resilience and AAD. The usefulness of the 'Trauma Grid' in the therapeutic process with refugees is also discussed. The Trauma Grid avoids global impressions and enables a more comprehensive and systematic way of identifying the individual refugee's functioning in the context of different levels, i.e. individual, family, community and society/culture. Finally, I discuss implications for therapeutic work with refugees
Sedimentology and isotope geochemistry of transitional evaporitic environments within arid continental settings: From erg to saline lakes
Arid continental basins typically contain a spectrum of coeval environments that coexist and interact from proximal to distal. Within the distal portion, aeolian ergs often border playa, or perennial, desert lakes, fed by fluvial incursions or elevated groundwaters. Evaporites are common features in these dryland, siliciclastic dominant settings. However, sedimentary controls upon evaporite deposition are not widely understood, especially within transitional zones between coeval clastic environments that are dominantly controlled by larger scale allocyclic processes, such as climate. The sulphur (δ34S) and oxygen (δ18O, Δ17O) isotope systematics of evaporites can reveal cryptic aspects of sedimentary cycling and sulphate sources in dryland settings. However, due to the lack of sedimentological understanding of evaporitic systems, isotopic data can be easily misinterpreted. This work presents detailed sedimentological and petrographic observations, coupled with δ34S, δ18O and Δ17O data, for the early Permian Cedar Mesa Sandstone Formation (western USA). Depositional models for mixed evaporitic / clastic sedimentation, which occurs either in erg‐marginal or lacustrine‐marginal settings, are presented to detail the sedimentary interactions present in terms of climate variations that control them. Sedimentological and petrographical analysis of the evaporites within the Cedar Mesa Sandstone Formation reveal a continental depositional environment and two end member depositional models have been developed: erg‐margin and lake‐margin. The δ34S values of gypsum deposits within the Cedar Mesa Sandstone Formation are consistent with late Carboniferous to early Permian marine settings. However, a marine interpretation is inconsistent with sedimentological and petrographic evidence. Consequently, δ34S, δ18O and Δ17O values are probably recycled and do not reflect ocean‐atmosphere values at the time of evaporite precipitation. They are most likely derived from the weathering of older marine evaporites in the hinterland. Thus, the results demonstrate the need for a combination of both sedimentological and geochemical analysis of evaporitic systems to better understand their depositional setting and conditions
Preliminary Limits on the WIMP-Nucleon Cross Section from the Cryogenic Dark Matter Search (CDMS)
We are conducting an experiment to search for WIMPs, or weakly-interacting
massive particles, in the galactic halo using terrestrial detectors. This
generic class of hypothetical particles, whose properties are similar to those
predicted by extensions of the standard model of particle physics, could
comprise the cold component of non-baryonic dark matter. We describe our
experiment, which is based on cooled germanium and silicon detectors in a
shielded low-background cryostat. The detectors achieve a high degree of
background rejection through the simultaneous measurement of the energy in
phonons and ionization. Using exposures on the order of one kilogram-day from
initial runs of our experiment, we have achieved (preliminary) upper limits on
the WIMP-nucleon cross section that are comparable to much longer runs of other
experiments.Comment: 5 LaTex pages, 5 eps figs, epsf.sty, espcrc2dsa2.sty. Proceedings of
TAUP97, Gran Sasso, Italy, 7-11 Sep 1997, Nucl. Phys. Suppl., A. Bottino, A.
di Credico and P. Monacelli (eds.). See also http://cfpa.berkeley.ed
Photoreduction of Shewanella oneidensis Extracellular Cytochromes by Organic Chromophores and Dye-Sensitized TiO2.
The transfer of photoenergized electrons from extracellular photosensitizers across a bacterial cell envelope to drive intracellular chemical transformations represents an attractive way to harness nature's catalytic machinery for solar-assisted chemical synthesis. In MR-1 (MR-1), trans-outer-membrane electron transfer is performed by the extracellular cytochromes MtrC and OmcA acting together with the outer-membrane-spanning porincytochrome complex (MtrAB). Here we demonstrate photoreduction of solutions of MtrC, OmcA, and the MtrCAB complex by soluble photosensitizers: namely, eosin Y, fluorescein, proflavine, flavin, and adenine dinucleotide, as well as by riboflavin and flavin mononucleotide, two compounds secreted by MR-1. We show photoreduction of MtrC and OmcA adsorbed on Ru-dye-sensitized TiO nanoparticles and that these protein-coated particles perform photocatalytic reduction of solutions of MtrC, OmcA, and MtrCAB. These findings provide a framework for informed development of strategies for using the outer-membrane-associated cytochromes of MR-1 for solar-driven microbial synthesis in natural and engineered bacteria.This work was supported by the UK Biotechnology and Biological Sciences Research Council (grants BB/K009753/1, BB/K010220/1, BB/K009885/1, and BB/K00929X/1), the Engineering and Physical Sciences Research Council (EP/M001989/1, PhD studentship 1307196 to E.V.A.), a Royal Society Leverhulme Trust Senior Research Fellowship to J.N.B., the Christian Doppler Research Association, and OMV group
Gene Bionetwork Analysis of Ovarian Primordial Follicle Development
Ovarian primordial follicles are critical for female reproduction and comprise a finite pool of gametes arrested in development. A systems biology approach was used to identify regulatory gene networks essential for primordial follicle development. Transcriptional responses to eight different growth factors known to influence primordial follicles were used to construct a bionetwork of regulatory genes involved in rat primordial follicle development. Over 1,500 genes were found to be regulated by the various growth factors and a network analysis identified critical gene modules involved in a number of signaling pathways and cellular processes. A set of 55 genes was identified as potential critical regulators of these gene modules, and a sub-network associated with development was determined. Within the network two previously identified regulatory genes were confirmed (i.e., Pdgfa and Fgfr2) and a new factor was identified, connective tissue growth factor (CTGF). CTGF was tested in ovarian organ cultures and found to stimulate primordial follicle development. Therefore, the relevant gene network associated with primordial follicle development was validated and the critical genes and pathways involved in this process were identified. This is one of the first applications of network analysis to a normal developmental process. These observations provide insights into potential therapeutic targets for preventing ovarian disease and promoting female reproduction
Improving corporate governance in state-owned corporations in China: which way forward?
This article discusses corporate governance in China. It outlines the basic agency problem in Chinese listed companies and questions the effectiveness of the current mechanisms employed to improve their standards of governance. Importantly, it considers alternative means through which corporate practice in China can be brought into line with international expectations and stresses the urgency with which this task must be tackled. It concludes that regulators in China must construct a corporate governance model which is compatible with its domestic setting and not rush to adopt governance initiatives modelled on those in cultures which are fundamentally different in the hope of also reproducing their success
Amblyopia and quality of life: a systematic review
Background/Aims
Amblyopia is a common condition which can affect up to 5% of the general population. The health-related quality of life (HRQoL) implications of amblyopia and/or its treatment have been explored in the literature.
Methods
A systematic literature search was undertaken (16th-30th January 2007) to identify the HRQoL implications of amblyopia and/or its treatment.
Results
A total of 25 papers were included in the literature review. The HRQoL implications of amblyopia related specifically to amblyopia treatment, rather than the condition itself. These included the impact upon family life; social interactions; difficulties undertaking daily activities; and feelings and behaviour. The identified studies adopted a number of methodologies. The study populations included; children with the condition; parents of children with amblyopia; and adults who had undertaken amblyopia treatment as a child. Some studies developed their own measures of HRQoL, and others determined HRQoL through proxy measures.
Conclusions
The reported findings of the HRQoL implications are of importance when considering the management of cases of amblyopia. Further research is required to assess the immediate and long-term effects of amblyopia and/or its treatment upon HRQoL using a more standardised approach
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