10 research outputs found
Can Photo- and Cathodoluminescence be Regarded as Complementary Techniques?
Photoluminescence (PL) usually provides macroscopic, high quality spectroscopic data. Cathodoluminescence (CL), on the other hand, offers the same information with microscopic imaging. However, replicating PL signatures in a CL system is not straightforward since matching experimental conditions, such as temperature and excitation density, is difficult. The matter is further exacerbated by inherent differences in the nature of excitation: electrons versus photons. Our work with high purity semiconductors suggests that CL is generally more sensitive to excitation circumstance than PL. For example, electrons can cause sample charging and contamination-related phenomena that dramatically affect CL. Changes in surface attributes (e.g., by chemical passivation) also affect PL and CL signals differently. Here, we extend previous work on GaAs by exploring the role of surface topography (by atomic force microscopy) and temperature (1.8K-100K) on excitonic lineshapes. We find that topographic subtleties strongly influence the character of exciton-polariton luminescence. We interpret these changes in terms of non-classical scattering phenomena derived from microscopic roughness. These microscopic changes also influence the temperature behaviour of excitons in crystals. Specifically, we find that passivated samples are brighter partly because there is a corresponding reduction in the (Arrhenius) activation energy for excitonic processes. In summary, the changes in surface topography and corresponding recombination physics seem well correlated
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POPOVER Review Panel report
The POPOVER series of high explosive (HE) certification tests was conducted at the Big Explosives Experimental Facility (BEEF) in Area 4 of the Nevada Test Site (NTS). The two primary objectives of POPOVER were to certify that: (1) BEEF meets DOE requirements for explosives facilities and is safe for personnel-occupied operations during testing of large charges of conventional HE. (2) Facility structures and equipment will function as intended when subjected to the effects of these charges. After careful analysis of test results, the POPOVER Review Panel concludes that the POPOVER series met both objectives. Further details on the Review Panel`s conclusions are included in Section 7--Findings and Recommendations
A physical map of the chicken genome
Strategies for assembling large, complex genomes have evolved to include a combination of whole-genome shotgun sequencing and hierarchal map-assisted sequencing. Whole-genome maps of all types can aid genome assemblies, generally starting with low-resolution cytogenetic maps and ending with the highest resolution of sequence. Fingerprint clone maps are based upon complete restriction enzyme digests of clones representative of the target genome, and ultimately comprise a near-contiguous path of clones across the genome. Such clone-based maps are used to validate sequence assembly order, supply long-range linking information for assembled sequences, anchor sequences to the genetic map and provide templates for closing gaps. Fingerprint maps are also a critical resource for subsequent functional genomic studies, because they provide a redundant and ordered sampling of the genome with clones. In an accompanying paper we describe the draft genome sequence of the chicken, Gallus gallus, the first species sequenced that is both a model organism and a global food source. Here we present a clone-based physical map of the chicken genome at 20-fold coverage, containing 260 contigs of overlapping clones. This map represents approximately 91% of the chicken genome and enables identification of chicken clones aligned to positions in other sequenced genomes
Correlates of the Eysenck personality profiler
In this two part study, 811 participants completed the Eysenck Personality Profiler (EPP) and the Honey and Mumford Learning Styles Questionnaire (LSQ) and 263 adults completed the EPP and the Myers-Briggs Type Indicator (MBTI). As predicted there were many significant correlations which add to the concurrent validity of the EPP. When the overlap of the EPP with the MBTI and LSQ is compared with the overlap of the NEO-PI with the MBTI and LSQ (derived from Furnham, 1996a,b) it appears that the EPP has greater similarity with the LSQ, but the NEO-PI has greater similarity with the MBTI. (C) 2001 Elsevier Science Ltd. All rights reserved
Genome Res.
As part of the effort to sequence the genome of Rattus norvegicus, we constructed a physical map comprised of fingerprinted bacterial artificial chromosome (BAC) clones from the CHORI-230 BAC library. These BAC clones provide 13-fold redundant coverage of the genome and have been assembled into 376 fingerprint contigs. A yeast artificial chromosome (YAC) map was also constructed and aligned with the BAC map via fingerprinted BAC and P1 artificial chromosome clones (PACs) sharing interspersed repetitive sequence markers with the YAC-based physical map. We have annotated 95% of the fingerprint map clones in contigs with coordinates on the version 3.1 rat genome sequence assembly, using BAC-end sequences and in silico mapping methods. These coordinates have allowed anchoring 358 of the 376 fingerprint map contigs onto the sequence assembly. Of these, 324 contigs are anchored to rat genome sequences localized to chromosomes, and 34 contigs are anchored to unlocalized portions of the rat sequence assembly. The remaining 18 contigs, containing 54 clones, still require placement. The fingerprint map is a high-resolution integrative data resource that provides genome-ordered associations among BAC, YAC, and PAC clones and the assembled sequence of the rat genome. [Supplemental material is available online at www.genome.org.
Genome Res
As part of the effort to sequence the genome of Rattus norvegicus, we constructed a physical map comprised of fingerprinted bacterial artificial chromosome (BAC) clones from the CHORI-230 BAC library. These BAC clones provide ~13-fold redundant coverage of the genome and have been assembled into 376 fingerprint contigs. A yeast artificial chromosome (YAC) map was also constructed and aligned with the BAC map via fingerprinted BAC and P1 artificial chromosome clones (PACs) sharing interspersed repetitive sequence markers with the YAC-based physical map. We have annotated 95% of the fingerprint map clones in contigs with coordinates on the version 3.1 rat genome sequence assembly, using BAC-end sequences and in silico mapping methods. These coordinates have allowed anchoring 358 of the 376 fingerprint map contigs onto the sequence assembly. Of these, 324 contigs are anchored to rat genome sequences localized to chromosomes, and 34 contigs are anchored to unlocalized portions of the rat sequence assembly. The remaining 18 contigs, containing 54 clones, still require placement. The fingerprint map is a high-resolution integrative data resource that provides genome-ordered associations among BAC, YAC, and PAC clones and the assembled sequence of the rat genome
Integrated and Sequence-Ordered BAC- and YAC-Based Physical Maps for the Rat Genome
As part of the effort to sequence the genome of Rattus norvegicus, we constructed a physical map comprised of fingerprinted bacterial artificial chromosome (BAC) clones from the CHORI-230 BAC library. These BAC clones provide ∼13-fold redundant coverage of the genome and have been assembled into 376 fingerprint contigs. A yeast artificial chromosome (YAC) map was also constructed and aligned with the BAC map via fingerprinted BAC and P1 artificial chromosome clones (PACs) sharing interspersed repetitive sequence markers with the YAC-based physical map. We have annotated 95% of the fingerprint map clones in contigs with coordinates on the version 3.1 rat genome sequence assembly, using BAC-end sequences and in silico mapping methods. These coordinates have allowed anchoring 358 of the 376 fingerprint map contigs onto the sequence assembly. Of these, 324 contigs are anchored to rat genome sequences localized to chromosomes, and 34 contigs are anchored to unlocalized portions of the rat sequence assembly. The remaining 18 contigs, containing 54 clones, still require placement. The fingerprint map is a high-resolution integrative data resource that provides genome-ordered associations among BAC, YAC, and PAC clones and the assembled sequence of the rat genome
Investigating the effects of personality traits on pair programming in a higher education setting through a family of experiments
Evidence from our systematic literature review revealed numerous inconsistencies in findings from the Pair Programming (PP) literature regarding the effects of personality on PP’s effectiveness as a pedagogical tool. In particular: i) the effect of differing personality traits of pairs on the successful implementation of pair-programming (PP) within a higher education setting is still unclear, and ii) the personality instrument most often used had been Myers-Briggs Type Indicator (MBTI), despite being an indicator criticized by personality psychologists as unreliable in measuring an individual’s personality traits. These issues motivated the research described in this paper. We conducted a series of five formal experiments (one of which was a replicated experiment), between 2009 and 2010, at the University of Auckland, to investigate the effects of personality composition on PP’s effectiveness. Each experiment looked at a particular personality trait of the Five-Factor personality framework. This framework comprises five broad traits (Openness to experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism), and our experiments focused on three of these - Conscientiousness, Neuroticism, and Openness. A total of 594 undergraduate students participated as subjects. Overall, our findings for all five experiments, including the replication, showed that Conscientiousness and Neuroticism did not present a statistically significant effect upon paired students’ academic performance. However, Openness played a significant role in differentiating paired students’ academic performance. Participants’ survey results also indicated that PP not only caused an increase in satisfaction and confidence levels but also brought enjoyment to the tutorial classes and enhanced students’ motivation