16 research outputs found
Orange emission in Pr3+-doped fluoroindate glasses
We synthesize and study the properties of praseodymium doped fluoroindate glasses. Glass compositions with praseodymium molar concentrations up to 5% were obtained with good optical quality. Thermal, optical, and luminescence properties are investigated. Judd–Ofelt analysis is used to determine radiative lifetime and emission cross-section of the orange transition originating from the 3P0 level. We find that these glasses are good candidates for the realization of blue diode laser pumped orange lasers for quantum information processing applications
Circumstellar interaction in supernovae in dense environments - an observational perspective
In a supernova explosion, the ejecta interacting with the surrounding
circumstellar medium (CSM) give rise to variety of radiation. Since CSM is
created from the mass lost from the progenitor star, it carries footprints of
the late time evolution of the star. This is one of the unique ways to get a
handle on the nature of the progenitor star system. Here, I will focus mainly
on the supernovae (SNe) exploding in dense environments, a.k.a. Type IIn SNe.
Radio and X-ray emission from this class of SNe have revealed important
modifications in their radiation properties, due to the presence of high
density CSM. Forward shock dominance of the X-ray emission, internal free-free
absorption of the radio emission, episodic or non-steady mass loss rate,
asymmetry in the explosion seem to be common properties of this class of SNe.Comment: Fixed minor typos. 31 pages, 9 figures, accepted for publication in
Space Science Reviews. Chapter in International Space Science Institute
(ISSI) Book on "Supernovae" to be published in Space Science Reviews by
Springe
Factor Structure and Correlates of the Dissociative Experiences Scale in a Large Offender Sample
The authors examined the psychometric properties, factor structure, and construct validity of the Dissociative Experiences Scale (DES) in a large offender sample (N = 1,515). Although the DES is widely used with community and clinical samples, minimal work has examined offender samples. Participants were administered self-report and interview measures, and a subsample was followed longitudinally to determine criminal and violent recidivism. The DES exhibited good psychometric properties, but an identified three-factor structure was of questionable replicability. Moreover, the DES factors displayed no evidence of differential correlates. DES total scores were correlated with trauma-related variables even after controlling for negative affectivity. Total scores were related to measures of antisocial behavior and aggression but did not predict recidivism. These findings support the reliability and construct validity of the DES in offenders but raise questions regarding the clinical utility of the DES factor scores above and beyond that of the total score
Entrepreneurial education’s and entrepreneurial role models’ influence on career choice
Orientation: Little research has been done into the impact of entrepreneurial education and entrepreneurial role models on entrepreneurship as a career choice, especially in developing countries.
Research purpose: The purpose of the study is to firstly explore the differences in entrepreneurial intentions between entrepreneurship students and non-entrepreneurship students, and secondly to investigate the relationship between entrepreneurial education and entrepreneurial intentions as well as between role models and entrepreneurial intentions.
Motivation for the study: There is a need for stakeholders, such as training authorities and training providers, to understand the influence of entrepreneurship education and role models on entrepreneurial career choice. Knowing this could assist in developing and implementing more effective entrepreneurial education programmes.
Research design, approach and method: The study was conducted amongst a convenience sample of 269 final-year students, of which 162 (60.2%) were entrepreneurship and 107 (39.8%) non-entrepreneurship students from a higher education institution in Johannesburg. The entrepreneurial intentions of entrepreneurship students were compared with those of non-entrepreneurship students. The findings of the study suggest that entrepreneurship students have stronger entrepreneurial intentions than non-entrepreneurship students, and that there is a positive relationship between entrepreneurship education and entrepreneurial intentions and between role models and entrepreneurial intentions respectively.
Practical/managerial implications: Entrepreneurship stakeholders can use the findings of the study to improve curriculum design, delivery methods and assessment strategies in their efforts to advance entrepreneurship.
Contribution/value-add: The findings of the study suggest that entrepreneurship education and role models can influence students’ entrepreneurial intentions in a developing country