Measuring the disparity among scientific disciplines using Library of Congress Subject Headings

Scientometrics - Examining the relationships among scientific disciplines is important today, but existing methods are limited by the contents and structure of their bibliographic databases. We...     

Untapped Knowledge about Water Reuse: the Roles of Direct and Indirect Educational Messaging

Water Resources Management - Public awareness of water quality concerns has increased since the Flint, MI crisis, but knowledge about water resources management remains low. Consequently,...     

High performance laser with nanopatterned active layer by selective area epitaxy

Lasers containing a nanopatterned active layer demonstrating excellent threshold characteristics are presented. The nanopatterned active layer is fabricated using high-resolution electron beam lithography and selective-area metal organic chemical vapour deposition crystal growth. Results demonstrating an order of magnitude improvement over previous results are reported.     

A Novel Ordered Nanopore Array Diode Laser

In this work, we have created a new type of structure, the nanopore active layer, for achieving quantization of carrier states in a semiconductor. The nanopore structure consists of a periodic two-dimensional array of localized energy barriers perturbing an otherwise conventional quantum well. This perturbation leads to the formation of intraband forbidden energy gaps which are observed experimentally.     

Organization of the visual reticular thalamic nucleus of the rat

The visual sector of the reticular thalamic nucleus has come under some intense scrutiny over recent years, principally because of the key role that the nucleus plays in the processing of visual information. Despite this scrutiny, we know very little of how the connections between the reticular nucleus and the different areas of visual cortex and the different visual dorsal thalamic nuclei are organized. This study examines the patterns of reticular connections with the visual cortex and the dorsal thalamus in the rat, a species where the visual pathways have been well documented. Biotinylated dextran, an anterograde and retrograde tracer, was injected into different visual cortical areas [17; rostral 18a: presumed area AL: (anterolateral); caudal 18a: presumed area LM (lateromedial); rostral 18b: presumed area AM (anteromedial); caudal 18b: presumed area PM (posteromedial)] and into different visual dorsal thalamic nuclei (posterior thalamic, lateral geniculate nuclei), and the patterns of anterograde and retrograde labelling in the reticular nucleus were examined. From the cortical injections, we find that the visual sector of the reticular nucleus is divided into subsectors that each receive an input from a distinct visual cortical area, with little or no overlap. Further, the resulting pattern of cortical terminations in the reticular nucleus reflects largely the patterns of termination in the dorsal thalamus. That is, each cortical area projects to a largely distinct subsector of the reticular nucleus, as it does to a largely distinct dorsal thalamic nucleus. As with each of the visual cortical areas, each of the visual dorsal thalamic (lateral geniculate, lateral posterior, posterior thalamic) nuclei relate to a separate territory of the reticular nucleus, with little or no overlap. Each of these dorsal thalamic territories within the reticular nucleus receives inputs from one or more of the visual cortical areas. For instance, the region to the reticular nucleus that is labelled after an injection into the lateral geniculate nucleus encompasses the reticular regions which receive afferents from cortical areas 17, rostral 18b and caudal 18b. These results suggest that individual cortical areas may influence the activity of different dorsal thalamic nuclei through their reticular connections.     

Play therapy for multicultural populations: Guidelines for mental health professionals.

Describes methods and techniques of play therapy for use with multicultural and diverse populations. Barriers to counseling multicultural children and Eurocentric play therapy techniques with multicultural populations are highlighted. Specific guidelines and examples for play therapy with multicultural children are provided. Recommendations and implications for mental health professionals are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceived race-based discrimination, employment status, and job stress in a national sample of black women: implications for health outcomes

This study examined concordance between self-reported drug use and urinalysis data among 341 applicants for methadone treatment in Sydney, Australia. Rates of under-reporting of use of specific drugs were low (0% to 10%). Irregular drug use, short half-life of some abused drugs, and relatively low sensitivity of the TLC assay procedure led to most detected drugs being found in only one of two urine samples collected. Subjects reported having recently used nearly twice as many drugs as were detected in their urine. Agreement (kappa) between self-report and urinalysis results was in the fair to good range for most drugs. None of the six predictors of misreporting examined were found to be of practical value.     

MQW wavelength-tunable DBR lasers with monolithically integrated external cavity electroabsorption modulators with low-driving voltages fabricated by selective-area MOCVD

The design and operation of multiple-quantum-well (MQW) wavelength-tunable distributed Bragg reflector (DBR) InGaAs QW lasers with nonabsorbing gratings and monolithically integrated external cavity electroabsorption modulators fabricated by selective-area MOCVD are presented. Uncoated devices exhibit CW threshold currents as low as 10.5 mA with slope efficiencies of 0.21 W/A from the laser facet. Wavelength tuning of 7 nm is obtained by injection current heating of the DBR section. These devices also exhibit extinction ratios of 18 dB from the modulator facet at a low modulator bias of 1 V, when measured with a broad-area detector. When coupled to a singlemode fiber, these devices exhibited high extinction ratios of 40 dB at a modulator bias of 1.25 V.