Comparative electron impact and fast atom bombardment mass spectrometric studies of some HMPA adducts of phenyltin and phenyllead halides and studies of strong hydrogen bonding by FAB-MS

The fragmentation patterns and mass spectra of some phenyl tin and -lead halide adducts with hexamethylphosphoramide are compared by subjecting them t~ electron impact and fast atom bombardment ionization in a mass spectrometer. This comparison is restricted to the metal-containing ions. Ligand-exchange mechanisms of some of the metal-containing species are explored by FAB-MS. Several moisturesensitive organo-metallics and H-bonded systems have been examined by FAB for attempted characterization, but without any success. Scavenging and trapping of water molecules by complex aggregates in solutions of quaternary ammonium fluorides and hydroxides are investigated by FAB to complement previous NMR-studies.

Comparison of two measures of PSI electron transport in winter rye

The number of P700 (the reaction centre of Photosystem I) converted to P700+, in winter rye, was determined by measuring the absorbance change at 820nm . It was found, with a single turnover flash, that thylakoids isolated from cold grown plants have a 50% greater number of P700 oxidized than thylakoids isolated from warm grown plants. Incubation of thylakoids in the dark at 35 C did not change the number of P700 oxidized. The conversion of P700 to P700+ with a single flash can be compared to a steady state rate of electron transport using a Clark electrode. The results for P700 oxidation using the absorbance change at 820 nm measure effects within the PSI complex whereas the results obtained from a Clark electrode measures steady state electron transport between the cytochrome blf complex and the PSI complex. In contrast to the results for P700 oxidation it was shown, using a Clark electrode, that both thylakoids from cold grown plants and thylakoids incubated at in the dark 35 C exhibited 50% higher rates of electron transport than thylakoids from warm grown plants. The correlation between the higher rate of steady state PSI electron transport observed in thylakoids isolated from cold grown winter rye and number of active PSI reaction centres localizes the site of the increase to the PSI reaction centre. In contrast the lack of correlation after incubation at 35 C indicates the increase in the rate of light saturated electron transport in thylakoids isolated from cold grown plants and thylakoids incubated in the dark at 35 C occur by different mechanisms.

Composition analysis of high-Tc superconducting thin films by quantitative x-ray fluorescence

A method is presented for determining the composition of thin films containing the elements Bi, Sr, Br, Cu, and Ca. Quantitative x-ray fluorescence (XRF) consisting of radioactive sources (secondary foil excitor 241Am-Mo source and 55Pe source), a Si(Li) detector, and a multichannel analyzer were employed. The XRF system was calibrated by using sol gel thin films of known element composition and also by sputtered thin films analyzed by the conventional Rutherford Back Scattering (RBS). The XRF system has been used to assist and optimize the sputter target composition required to produce high-Tc BiSrCaCuO films with the desired metal composition.

Concept analysis in social studies

This project was undertaken because of a need to analyse concepts in social science more specifically and sequence them more carefully in a social science program. Concepts have been identified vaguely on many curriculum documents or left in isolation from each other when they are specifically identified. The project's aim was to identify a method for analysing concepts and sequencing their teaching on some rational basis. Once the method for analysing concepts was identified a questionnaire was designed and administered to a random sample of students at the grade three, five and eight levels. The questionnaire attempted to measure their comprehension of specific social science concepts at several levels which became progressively more complex. The major hypothesis was that there would be a direct correlation between age and achievement on the questionnaire. The raw scores were seriated and correlated with the ages of the students using the rankdifference- squared method. For the majority of areas tested it was found that there was a significant correlation between age and achievement on the questionnaire. Variation in the correlation coefficients generated suggests that comprehension of social science concepts is not simply a function of age but is probably a function of several inter-related factors such as reading ability, skill in Basic Thinking Skills and age. Thirty students completed each test. There were three tests in the questionnaire.

Construing social dimensions of personality development: nurses as educators

A convenience sample of twenty registered nurses was recruited from two' general hospitals and two community college nursing schools. Kelly's (1955) Personal Construct Theory provided the theoretical framework to discover how nurses perceived themselves as educators. The nurses completed a self-administered Self-Perception Inventory (Soares, 1983) to determine their perception of self as nurse and ideal self as nurse. In an interview, each of the nurses constructed a rank-order repertory grid adapted from Kelly's (1955) Role Repertory Construct Test. Twelve constructs derived from the Self-Perception Inventory (Soares, 1983) were ranked according to a list of ten elements common to a teaching situation. Rank order correlations among the constructs were determined with Spearman's rho. Using a dependent samples t-test, significant differences were found between perceptions of current and ideal self for staff nurses. Significant differences were also found between nurse educators' perceptions of self and ideal self as nurse. No significant differences were determined in perceptions of self as nurse and ideal self as nurse between the staff nurse and nurse educator groups with an independent samples t-test. However, observations of single constructs revealed that although several constructs are shared between the groups in the perception of self in a teaching situation, both groups hold constructs that operate exclusively in their separate domains. The nature and strength of the relationships between the common and unique constructs are different for each group. Nurses I self-perceptions appear to be influenced by the historical development of nursing, role socialization during nursing education, social expectations and gender issues in the health care system.

Continuous hydride generation in the presence of L- cysteine for the determination of arsenic, bismuth, antimony and tin in steels by inductively coupled plasma atomic emission spectrometry

Arsenic, bismuth, germanium, antimony and tin were simultaneously determined by continuous hydride generation and inductively coupled plasma-atomic emission spectrometry . I Hydrides were introduced into four different types of gas-liquid separators. Two of the gas-liquid separators were available in-house. A third was developed for this project and a fourth was based on a design used by CET AC. The best signal intensity was achieved by the type II frit-based gas-liquid separator, but the modified Cetac design gave promise for the future, due to low relative standard deviation. A method was developed for the determination of arsenic, bismuth, antimony and tin in low-alloy steels. Four standard reference materials from NIST were dissolved in 10 mL aqua regia without heat. Good agreement was obtained between experimental values and certified values for arsenic, bismuth, antimony and tin. The method was developed to provide the analyst with the opportunity to determine the analytes by using simple aqueous standards to prepare calibration lines. Within the limits of the samples analyzed, the method developed is independent of matrix.

Co-operative education and the development of self-esteem, an internal locus of control and work habits

This study compared approximately 50 grade 12 students studying In th~ co-operative education mode with approximately 50 grade 12 students studying in a traditional English course. Measures of self-esteem, locus of control and work habits were compared before and at the conclusion of one semester's involvement in the different programs. Using Coopersmith's Self-Esteem Inventory, the students who had chosen to study in the co-operative education mode scored significantly higher than the students in the traditional course. At the end of the semester, the co-operative education students' scores remained significantly higher than the English students'. Although the test showed no sjgnifi~ant changes in self-esteem. anecdotal reports indicated that co-operative education students had increased self-esteem over the semester. No significant differences in locus of control were observed between the two groups at any time. Significant differences in work habits were observed. While both groups had the same number of absences and the same marks before taking these courses, students who were involved in co-operative education had significantly fewer absences and significantly higher marks than the students studying in the traditional course. Anecdotal reports also indicated an improv~ment in work habits for students who had been involved in co-operative education. Recommendations of the study are for further research to determine more exactly how self-esteem and work habits develop in co-operative education students. Also. students. parents, teachers. and administrators need to be made aware of the success of this program.

Cooperative learning and elaborative interrogation: effects on children's learning

This experimental study examined the effects of cooperative learning and a question-answering strategy called elaborative interrogation ("Why is this fact true?") on the learning of factual information about familiar animals. Retention gains were compared across four study conditions: elaborative-interrogation-plus-cooperative learning, cooperative-learning, elaborative-interrogation, and reading-control. Sixth-grade students (n=68) were randomly assigned to the four conditions. All participants were given initial training and practice in cooperative learning procedures via three 45-minute sessions. After studying 36 facts about six animals, students' retention gains were measured via immediate free recall, immediate matched association, 30-day, and GO-day matched association tests. A priori comparisons were made to analyze the data. For immediate free recall and immediate matched association, significant differences were found between students in the three experimental conditions versus those in the control condition. Elaborative-interrogation and elaborativeinterrogation- plus-cooperative-learning also promoted longterm retention (measured via 30-day matched association) of the material relative to repetitive reading with elaborative-interrogation promoting the most durable gains (measured via GO-day matched association). The relationship between the types of elaborative responses and probability of subsequent retention was also examined. Even when students were unable to provide adequate answers to the why questions, learning was facilitated more so than repetitive reading. In general, generation of adequate elaborations was associated with greater probability of recall than was provision of inadequate answers. The findings of the study demonstrate that cooperative learning and the use of elaborative interrogation, both individually and collaboratively, are effective classroom procedures for facilitating children's learning of new information.

Correlates and outcomes of severe bullying: internalizing maladjustments of adolescent bullies, victims and bully- victims

The current study examined the association between involvement in bullying and victimization and internalizing difficulties such as self-esteem, social anxiety, depression and body image. Possible gender differences were also examined. The participants, high school students from Southern Ontario (N=533), were drawn from a larger, data set as part ofa study that was completed by the Youth Lifestyle Choices: Community Research Alliance (YLCCURA). The students completed a self-report questionnaire on a number ofmeasures; including, bullying, victimization, self-esteem, social anxiety, depression and body image. The results of this study suggest that those students who self-identified as victims and bully-victims also report higher levels of anxiety and depression than controls and bullies. Severe victims and bullyvictims had a lower body image than severe bullies and controls, whereas severe bullies seem to have a higher body image score than controls. These results are relevant when considering treatments and interventions for students experiencing adjustment difficulties who may also be at risk for bullying victimization. The results also suggest that particular attention needs to be focused on those adolescents who play multi-roles in bullying situations (i.e., bully-victims), since these students may come to the attention ofthe school system for externalizing behaviours, but may also need assistance for internalizing maladjustments.

Cytosolic calcium levels and stress induced y-amino butyrate synthesis in asparagus mesophyll cells

Numerous investigations have demonstrated large increases in y-amino butyrate (GABA) levels in response to a variety of stresses such as touch or cold shock (Wallace et ale 1984) Circumstantial evidence indicating a role of Ca2 + in these increases includes elevated Ca2+ levels in response to touch and cold shock (Knight et ale 1991), and the demonstration of a calmodulin binding domain on glutamate decarboxylase (GAD), the enzyme responsible for GABA synthesis (Baum et al 1993) In the present study the possible role of Ca2+ and calmodulin in stimulation of GAD and subsequent GABA accumulation was examined using asparagus mesophyll cells. Images of cells loaded with the Ca2+ indicator Fluo-3 revealed a rapid and transient increase in cytosolic Ca2+ in response to cold shock. GABA levels increased by 106% within 15 min. of cold shock. This increase was inhibited 70% by the calmodulin antagonist W7, and 42% by the Ca2+ channel blocker La3+.. Artificial elevation of intracellular Ca2+ by the Ca2+ionophore A23187 resulted in an 61% increase in GABA levels. Stimulation of GABA synthesis by ABA resulted in an 83% increase in GABA levels which was inhibited 55% by W7. These results support the hypothesis that cold shock stimulates Ca2+ entry into the cytosol of the cells which results in Ca2+/calmodulin mediated activation of GAD and consequent GABA synthesis.

Dechanneling of 2 Mev Heâ ½ in gold

Thick gold single crystals of high quality were prepared for Rutherford Backscattering Dechanneling studies by electropolishing and annealing. The variation.; with temperature of the Random Fraction versus Depth spectrtnn for 2 MeV He+ on < 110> gold was extracted from measured Aligned and Random (Energy) Spectra. The measured dechanneling rate showed a sixfold increase in going from 4loK to 293°K and is in reasonable agreement with calculations made using the Steady Increase in Transverse Energy (SITE) approximation.

Decision-making theory applied to India's explosion of a nuclear device in May, 1974

This essay reviews the decision-making process that led to India exploding a nuclear device in May, 1974. An examination of the Analytic, Cybernetic and Cognitive Theories of decision, will enable a greater understanding of the events that led up to the 1974 test. While each theory is seen to be only partially useful, it is only by synthesising the three theories that a comprehensive account of the 1974 test can be given. To achieve this analysis, literature on decision-making in national security issues is reviewed, as well as the domestic and international environment in which involved decisionmakers operated. Finally, the rationale for the test in 1974 is examined. The conclusion revealed is that the explosion of a nuclear device by India in 1974 was primarily related to improving Indian international prestige among Third World countries and uniting a rapidly disintegrating Indian societal consensus. In themselves, individual decision-making theories were found to be of little use, but a combination of the various elements allowed a greater comprehension of the events leading up to the test than might otherwise have been the case.

Developmental variations in the peripheral erythrocytic system of the rainbow trout, Salmo gairdneri

The peripheral circulating erythrocytic system of the rainbow trout, l3 almo gairdner , was examined in vitro in relation differences in the morphology and multiple hemoglobin system organization of adult and juvenile red cells. Cells were separated by velocity sedimentation under unit gravity, a procedure requiring red cell exposure to an incubation medium for periods of at least three hours. Therefore , this must provide an environment in which red cells remain in a condition approximaing normalcy. Previous studies having demonstrated commonly employed media to be ineffective in this regard , a medium was developed through modification of Cortl and saline. One of the principal additions to this me dium , norepinephrine, altered cell regulation of intracellular calcium, magnesium and chloride concentrations. Catecholamine involvement was also suggeste d in the synthes is of hemoglobin . The procedure was found to separtate cells primarily by density and, to a lesser extent, by shape. Characterization of red cells revealed two subpopulations to exist . The first comprised the bulk of the cell population, and were of greater l ength, width, volume and major:minor axis ratio than the smaller population; these were adult cells. The later, juvenile cells were of smaller overall size and were more spherical in shape . Juvenile cells also possessed fewer electrophore tpically distinguishable isomorphs than did adults with only eight of eleven hemoglobin component s typically found With maturation,hemoglobin complement with the development of three more bands. The total complement of the adult cell contained 7 cathodal bands and four anodal hemoglobin isomorphs. Bands acquired with maturation comprised the smallest percentage of the cells hemoglobin. each averaging less than one-percent of the total. Whether these additional bands are derived through degradation and reaggregation of existing components or are the product of pe gQy2 synthesis is not yet known.