Examining Micro-Level (SQL) Curriculum-Oriented and Promotional IS Enrollment Strategies

Maintaining enrollments in information systems programs capable of meeting industry demands is an ongoing challenge. While significant research has been conducted examining macro-level strategies (e.g., promoting MIS activities), very few studies have examined micro- level strategies (e.g., promoting Structured Query Language). The purpose of this study is to empirically examine both curriculum-oriented and promotional interventions by introducing SQL into foundation information systems curricula. Based on the Theory of Reasoned Action (TRA), 180 students completed a survey to measure attitude, behavior norms, and plans to enroll in a database class in the future. Additionally, both the hands-on SQL instruction and the promotional SQL intervention played a moderating role on the impact attitude had on plans to take a database course. These results add to our pedagogical understanding of enrollment decisions as well as provide practical solutions educators may use to keep pace with enrollment demands.     

Photodegradation of CL-20: insights into the mechanisms of initial reactions and environmental fate

Hexanitrohexaazaisowurtzitane (HNIW) or CL-20 is a caged structure polycyclic nitramine that may replace RDX and HMX as a common use energetic chemical. To provide insight into the environmental fate of CL-20 we photolyzed the chemical in a Rayonet photoreactor (254-350 nm) and with sunlight in aqueous solutions. Previously, we found that initial photodenitration of the monocyclic nitramine RDX leads to ring cleavage and decomposition. Presently, we found that photolysis of the rigid molecule CL-20 produced NO2-, NO3-, NH3, HCOOH, N2 and N2O. Using LC/MS (ES-) we detected several key intermediates carrying important information on the initial steps involved in the degradation of CL-20. The identities of the intermediates were confirmed using a uniformly ring labeled 15N-[CL-20]. When CL-20 was photolyzed in the presence of H2(18)O, D2O or 18O2 we obtained a product distribution suggesting that the energetic chemical degraded via at least two initial routes; one involved sequential homolysis of N-NO2 bond(s) and another involved photorearrangement prior to hydrolytic ring cleavage and decomposition in water.     

Determination of five tetracyclines and their epimers by LC-MS/MS based on a liquid-liquid extraction with low temperature partitioning

An LC-MS/MS method is presented for screening five tetracyclines and their epimers in a broad range of food products. The scope of matrices includes meat-, fish-, seafood-based products, various dairy ingredients, infant formulae and fats. The method principle is based on a liquid–liquid extraction with aqueous ethylenediaminetetraacetic acid (EDTA) and acetonitrile followed by a freezing step to promote phase separation at low temperature. After defatting with hexane, sample extracts were evaporated and reconstituted before injection onto the LC-MS/MS system. The addition of oxalic acid in the aqueous mobile phase was mandatory to maintain good peak shape and sensitivity over the run. The screening is based upon a double preparation of each sample, one ‘as such’ and a second one with the analytes spiked in the sample, in order to mitigate the risk of false negative response. The method was validated according to the European Community Reference Laboratories Residues Guidelines. A total of 93 samples were included in the validation by two independent laboratories giving both false-negative and false-positive rates at 0% for all compounds. Over the last two years, 2600 samples were analysed routinely and only one chicken sample was found above the regulatory limit.     

Determination of 105 antibiotic,anti-inflammatory,antiparasitic agents and tranquilizers by LC-MS/MS based on an acidic QuEChERS-like extraction

A procedure for screening 105 veterinary drugs in foods by liquid chromatography tandem mass-spectrometry (LC-MS/MS) is presented. Its scope encompasses raw materials of animal origin (milk, meat, fish, egg and fat) but also related processed ingredients and finished products commonly used and manufactured by food business operators. Due to the complexity of the matrices considered and to efficiently deal with losses during extraction and matrix effects during MS source ionisation, each sample was analysed twice, that is ‘unspiked’ and ‘spiked at the screening target concentration’ using a QuEChERS-like extraction. The entire procedure was validated according to the European Community Reference Laboratories Residues Guidelines. False-negative and false-positive rates were below 5% for all veterinary drugs whatever the food matrix. Effectiveness of the procedure was further demonstrated through participation to five proficiency tests and its ruggedness demonstrated in quality control operations by a second laboratory.     

Performance of a digital symbol synchronizer in cochannel interference and noise

The performance of a binary-quantized data-transition tracking loop symbol synchronizer operating in cochannel interference (CCI) and noise is examined for both binary phase-shift keying and quaternary phase-shift keying modulations. The CCI can be included in a previously known Markov chain model without increasing the number of states in the chain, but the cost of computing the transition probabilities increases exponentially with the number of interferers. It is shown that a first-order Markov model and simulation are in close agreement for some important applications. The effect of interferer epoch on the degradation caused by the interference is investigated and the degradations in performance caused by CCI and by Gaussian noise are compared.     

Démarches méthodologiques pour approcher les points de vue d'enseignants et enseignantes sur des QSV en lien avec le vivant

Les avancées dans le domaine des biotechnologies ainsi que des questions relatives à la santé publique soulèvent des enjeux sociaux, éthiques et culturels se répercutant dans la recherche et l'enseignement des sciences. L'intégration scolaire de contenus liés à ces enjeux fait appel à des approches d'enseignement dont la visée intègre l'objectif de formation de citoyennes et citoyens réfléchis et critiques. La nécessité d'adopter des méthodes de recherche favorisant l’émergence de la pluralité des points de vue d'enseignantes et enseignants de sciences se pose alors devant la diversité de ces enjeux. Le recours à des méthodes issues de l'interactionnisme symbolique (récits de vie, groupes de discussion) peut répondre à cette nécessité. C'est ce que montre cet article qui illustre le caractère heuristique de ces démarches ainsi que la multidimensionnalité, la pluralité et l'hétérogénéité des points de vue pouvant être recueillis.     

Différences entre adolescents et adolescentes à quatre taches de visualisation spatiale.

Compared the performance of 64 adolescent boys and 42 adolescent girls (aged 15–17 yrs) on 4 visual-spatial skills tasks. The administrative conditions of these computerized tasks are highly standardized. Three of these tasks, Spatial Visualization, Perception and Spatial Relations, are taken from the Computerized Aptitude Test for adolescents and adults, whereas the 4th task is an adaptation for adolescents of the Puzzle subtest of the Computerized Aptitude Test for infants. The dependent variables are the average success scores and the speed of execution scores derived from latency times in a group of the best scores for each of the 4 tasks. The results show that the adolescent boys are more successful at the Spatial Visualization and Spatial Relations tasks. On the whole, the boys and the girls showed a comparable speed of success, except in the Spatial Relations subtest, where the girls were much faster. The observed differences are interpreted as reflecting the better strategies adopted by the boys to solve mental rotation tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)