A Faint Star-Forming System Viewed Through the Lensing Cluster Abell 2218: First Light at z~5.6?

We discuss the physical nature of a remarkably faint pair of Lyman alpha-emitting images discovered close to the giant cD galaxy in the lensing cluster Abell 2218 (z=0.18) during a systematic survey for highly-magnified star-forming galaxies beyond z=5. A well-constrained mass model suggests the pair arises via a gravitationally-lensed source viewed at high magnification. Keck spectroscopy confirms the lensing hypothesis and implies the unlensed source is a very faint (I~30) compact (<150 pc) and isolated object at z=5.576 whose optical emission is substantially contained within the Lyman alpha emission line; no stellar continuum is detectable. The available data suggest the source is a promising candidate for an isolated ~10^6 solar mass system seen producing its first generation of stars close to the epoch of reionization.Comment: 11 pages, 3 figures, to appear in Ap J Lett, minor revision following referee's repor

Non-Perturbative Formulation of Time-Dependent String Solutions

We formulate here a new world-sheet renormalization-group technique for the bosonic string, which is non-perturbative in the Regge slope alpha' and based on a functional method for controlling the quantum fluctuations, whose magnitudes are scaled by the value of alpha'. Using this technique we exhibit, in addition to the well-known linear-dilaton cosmology, a new, non-perturbative time-dependent background solution. Using the reparametrization invariance of the string S-matrix, we demonstrate that this solution is conformally invariant to alpha', and we give a heuristic inductive argument that conformal invariance can be maintained to all orders in alpha'. This new time-dependent string solution may be applicable to primordial cosmology or to the exit from linear-dilaton cosmology at large times

Narratives of resistance: (Re) Telling the story of the HIV/AIDS movement – Because the lives and legacies of Black, Indigenous, and People of Colour communities depend on it

Centering the narratives of the intersectional struggles within the HIV movement for Indigenous sovereignty, Black and People of Colour liberation, and LGBTQ rights tirelessly fought for by Black, Indigenous, and People of Colour communities legitimates their lives and legacies within the movement; and the relevance of a focused response to the HIV epidemic that continues to wreak devastation in these communities. The recent political push for a post-HIV era solely centers the realities of middle-class white, gay men and has genocidal implications for Black, Indigenous, and People of Colour communities

The blackness of the cosmic microwave background spectrum as a probe of the distance-duality relation

A violation of the reciprocity relation, which induces a violation of the distance duality relation, reflects itself in a change in the normalisation of the cosmic microwave spectrum in such a way that its spectrum is grey. We show that existing observational constraints imply that the reciprocity relation cannot be violated by more than 0.01% between decoupling and today. We compare this effect to other sources of violation of the distance duality relations which induce spectral distortion of the cosmic microwave background spectrum.Comment: 5 pages, 2 figures, references added, minor typos correcte

Juvenile Court: The Legal Process as a Rehabilitative Tool

The author\u27s study, reported in this comment, had two objectives. First, it attempted to determine whether a juvenile\u27s experience with the traditional sociological model or with the legal due process model is more likely to motivate him to feel positively toward the legal system. Second, this study attempted to measure the attitudes of the professionals in the juvenile system (judges, attorneys, and caseworkers) toward the two models. The results of the study, although not all were statistically significant, indicated that although the professionals favored the traditional sociological model, the use of the legal-due process model was more likely to result in the offender\u27s feeling that the legal system was fair. If, as a result of these positive feelings toward the legal system, the offender is more likely to become rehabilitated because of his perception of the legitimacy of the rule of law, then the legal due process model possesses more promise as a rehabilitative device than does the traditional sociological model

A Comparison between Assigned Topic and Unassigned Topic Writing Compositions of Fifth Grade Students

The purpose of this study was to determine if there was a statistically significant and important relationship between fifth grade students\u27 writing products when self-selected-topic compositions were compared to assigned-topic compositions. The study was conducted over an eight-week period of time with 88 fifth grade students from a suburban school in western New York. There were 48 boys and 40 girls in the study. Each student was requested to write two compositions; the first composition was based on a topic of the student\u27s own choice, the second composition was based on an assigned topic selected from a previous New York State Survey Test in Writing. Scores comparing self-selected-topic compositions to assigned-topic compositions were analyzed using the point biserial coeffecient of determination. An analysis of the data revealed no statistically significant and important relationships between the scores of self-selected-topic compositions and assigned-topic compositions. While the statistics were not sufficient to reach the criteria deemed educationally important , the general trend reflected higher mean scores for self-selected-topic compositions for both boys and girls. Girls acquired higher mean scores than the boys on both assigned and unassigned compositions. Students ranked as satisfactory writers by their classroom teachers exhibited the greatest increase in mean scores on unassigned-topic compositions. Based on this study, further research in the area of process writing and topic selection would benefit the educational system. Skills, acquired while writing compositions on self-selected topics, will transfer to other educational and content areas

Coherent Structures and Aeolian Saltation

Aeolian sand transport models, widely employed by coastal scientists and managers, assume temporal and spatial homogeneity within the saltation field. This research questions that assumption by demonstrating that the saltation field is event-driven, therefore indicating that the saltation field is not temporally steady. The findings from this research may explain a portion of the conclusions from previous studies that indicated inequalities between model-estimated and field-measured aeolian sand transport. The relationship between unsteadiness in a turbulent wind field and pulses in a sand transport field was investigated on a beach near Shoalhaven Heads, New South Wales, Australia. Microphone-based saltation sensors, “miniphones,” and thermal anemometers (both instruments constructed exclusively for this field experiment) were co-located (0.02 m separation on center) and deployed between 0.01 and 0.0225 m above the bed, and sampled at 6000 Hz. Average grain size at the field site was 0.30 mm. Five runs totaling 2050 seconds of wind and saltation data were analyzed. The continuous wavelet transform, using the Morlet wavelet base, was the principle method for analyzing the wind and saltation records. The cross continuous wavelet transform was used to analyze the wind and saltation time series concurrently. Wind, saltation, and cross events were discerned by selecting wavelet power coefficients between wavelet scales of 0.4 and 3.0 seconds and with coefficients exceeding the 95% confidence interval. Average event spacing was 6.10, 6.50, and 6.73 seconds for the wind, saltation, and cross events, respectively. The average event spacing measured in this research was compared to the empirical-based model presented by Rao, Narashimha, and Narayanan (1971). The correspondence between the model and this research strongly suggests that bursting-type coherent structures were present. The durations of average wind, saltation, and cross events were 1.87, 2.10, and 1.73 seconds, respectively. Integral time scales, calculated using normalized auto correlation and power spectral density analysis, were approximately two seconds for the wind and saltation systems. The temporal coincidence of the integral time scale estimations and the event durations for the wind and saltation system strongly suggests that wind events are driving sand transport events

Do Three Dimensions tell us Anything about a Theory of Everything?

It has been conjectured that four-dimensional N=8 supergravity may provide a suitable framework for a `Theory of Everything', if its composite SU(8) gauge fields become dynamical. We point out that supersymmetric three-dimensional coset field theories motivated by lattice models provide toy laboratories for aspects of this conjecture. They feature dynamical composite supermultiplets made of constituent holons and spinons. We show how these models may be extended to include N=1 and N=2 supersymmetry, enabling dynamical conjectures to be verified more rigorously. We point out some special features of these three-dimensional models, and mention open questions about their relevance to the dynamics of N=8 supergravity.Comment: 20 pages Latex, 2 eps figure

The Abundance of Low-luminosity Lyman alpha Emitters at High Redshift

We derive the luminosity function of high-redshift Lyman alpha emitting sources from a deep, blind, spectroscopic survey that utilized strong-lensing magnification by intermediate-redshift clusters of galaxies. We observed carefully selected regions near 9 clusters, consistent with magnification factors generally greater than 10 for the redshift range 4.5<z<6.7. Eleven emission-line candidates were located in the range 2.2<z<5.6 whose identification we justify as Lyman alpha, in most cases via further spectroscopic observations. The selection function we constructed for our survey takes into account our varying intrinsic Lyman alpha line sensitivity as a function of wavelength and sky position. By virtue of the strong magnification factor, we provide constraints on the Lyman alpha luminosity function to unprecedented limits of 10^40 erg/s, corresponding to a star-formation rate of 0.01 Msun/yr. Our cumulative z=5 Lyman alpha luminosity function is consistent with a power law form, n(>L) proportional to L^-1 over 10^41 to 10^42.5 erg/s. When combined with the results of other surveys, limited at higher luminosities, our results suggest evidence for the suppression of star formation in low-mass halos, as predicted in popular models of galaxy formation.Comment: 22 pages, 14 figures, submitted to Ap

Capacity Building: Lessons from a Pilot Programme with Black and Minority Ethnic Voluntary and Community Organisations

Despite the black and minority ethnic (BME) sector's ability to provide culturally appropriate services and to play an active and key role in civic engagement and social inclusion, BME organisations are often marginal to local policy debates and feel 'used by mainstream and statutory agencies to deliver the latter's goals and targets rather than being fully involved in strategic policy discussion' (Craig et al., 2002). Many BME groups experienced exclusion from the traditional structures of the voluntary and community sector, and from different levels of government decision making combined with a more stringent level of funding scrutiny (Craig et al., 2002), reflecting the racism experienced by the communities themselves. It is this inequality and marginalisation of certain groups from the process of mainstream society that the Council of Ethnic Minority Voluntary Organisations' capacity building programme challenged.The Joseph Rowntree Foundation (JRF) and CEMVO commissioned Charities Evaluation Services (CES) to evaluate the programme