Fundamental cryobiology of selected African mammalian spermatozoa and its role in biodiversity preservation through the development of genome resource banking

Fundamental cryobiological characteristics of spermatozoa from threatened or endangered species must be determined for successful cryopreservation techniques to be established. In this study, spermatozoa from four diverse species, impala (Aepyceros melampus), wart hog (Phacochoerus aethiopicus), elephant (Loxodonta africana), and lion (Panthera leo), were collected by electroejaculation or epididymal aspiration. Spermatozoal plasma membrane permeability to water (hydraulic conductivity, Lp) and the osmotically inactive fraction of the sperm cell (Vb) were determined from each species. Changes in cell volume were measured over time using an electronic particle counter. A Kedem-Katchalsky membrane transport model was used to theoretically characterize the data to determine Lp and Vb for each species. In addition to determining plasma membrane characteristics, spermatozoa were also studied to determine their sensitivity to low temperatures and to permeating cryoprotectant solutes. Cells maintained at room temperature (20-22 degrees C) were slowly or rapidly exposed to cold temperatures (1-4 degrees C), and percent motility was estimated to determine the sensitivity of the cells to cooling. Spermatozoa were also in media containing 1 M glycerol, dimethyl sulfoxide or ethylene glycol, and percent motility was measured at 15, 30 and 60 min intervals to determine the sensitivity of the cells to the cryoprotectant agent over time. Results indicate that sperm motility is significantly effected by decreased temperatures and the presence of cryoprotectant agents.     

Magnetic microactuation of polysilicon flexure structures

A microactuator technology that combines magnetic thin films with polysilicon flexural structures is described. Devices are constructed in a batch-fabrication process that combines electroplating with conventional lithography, materials, and equipment. A microactuator consisting of a 400×(47-40)×7 μm³ rectangular plate of NiFe attached to a 400×(0.9-1.4)×2.25 μm³ polysilicon cantilever beam has been displaced over 1.2 mm, rotated over 180°, and actuated with over 0.185 nNm of torque. The microactuator is capable of motion both in and out of the wafer plane and has been operated in a conductive fluid environment. Theoretical expressions for the displacement and torque are developed and compared to experimental results     

Employing people with disabilities: Impact of attitude and situation.

Examined the impact of attitude and hypothetical situational encounters on affective, behavioral and cognitive responses of nondisabled employees toward coworkers with disabilities. 176 Ss completed the Attitudes Toward Disabled Persons Scale, and responded to 1 of 9 situations of varying levels of intimacy in which they imagined themselves and a person with an immediately obvious disability. Their affective, behavioral and cognitive reactions were assessed by 3 different measures. Both more negative attitudes and situations with higher discomfort levels resulted in the most negative responses. Attitude and situation independently influenced responses. Findings provide a basis for interventions by rehabilitation professionals who work with individuals with disabilities and for employers seeking to implement the Americans with Disabilities Act. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The association between cigarette smoking and selected HIV-related medical conditions

OBJECTIVE: To clarify the effect of cigarette smoking on the development of conditions associated with HIV infection. DESIGN: Prospective and retrospective cohort study, with interview and examination twice a year since 1988. METHODS: Data on 516 HIV-infected men from cohorts of homosexual and bisexual men in San Francisco, Denver and Chicago, who were repeatedly interviewed and examined between 1988 and 1992, were analysed. After excluding men who did not have well-defined dates of seroconversion and those who were classified as ex- or intermittent smokers, 232 men remained for analysis: 106 were smokers and 126 were non-smokers. Univariate and Kaplan-Meier survival analyses were performed to assess the relationship between cigarette smoking and loss of CD4+ T-lymphocytes, diagnosis of any AIDS-defining illness, and specific diagnosis of Kaposi's sarcoma, Pneumocystis carinii pneumonia (PCP), oral candidiasis, hairy leukoplakia, and community-acquired pneumonia. RESULTS: By univariate analyses, cigarette smoking was not associated with clinical AIDS, loss of CD4+ cells, Kaposi's sarcoma or PCP, but was significantly associated with oral candidiasis [relative risk (RR), 1.32; 95% confidence interval (CI), 1.02-1.70], hairy leukoplakia (RR, 1.51; 95% CI, 1.15-1.99), and community-acquired pneumonia (RR, 2.62; 95% CI, 1.30-5.27). Dose-response effect was also evident for these three conditions (all P < 0.01). Kaplan-Meier survival analysis indicated no association between cigarette smoking and time of progression to clinical AIDS, Kaposi's sarcoma (KS), or PCP (P = 0.62, 0.54 and 0.11, respectively) but showed that cigarette smokers developed oral candidiasis, hairy leukoplakia, and pneumonia more quickly than non-smokers (P = 0.031, 0.006 and 0.009, respectively). CONCLUSIONS: Cigarette smoking was not associated with an increased likelihood or rate of developing KS, PCP or AIDS, but was associated with developing community-acquired pneumonia, oral candidiasis, and hairy leukoplakia in these HIV-infected men.     

Collaboration between pharmacy and laboratory: defining total allowable error limits for therapeutically monitored drugs

The incidence of serious breast pathology in children and adolescents is low. Despite this, children, adolescents, and their parents come to the primary care provider with many breast-related concerns. Tanner staging is a good predictor of ensuing physical sexual development and can be used as a tool to reassure the pubertal girl that she is normal. Variations such as polythelia, premature thelarche, gynecomastia, nipple irritation from exercise, and nipple piercing and tattooing can be managed with education and reassurance. Whereas breast cancer is extremely rare in adolescents, evaluation with ultrasonography may be indicated. The primary care provider plays a central role in educating young girls and adolescents about healthy breast practices such as avoidance of alcohol and cigarette smoking, exercise, low-fat diet, breast self-examination, and avoidance of piercing and tattooing.     

Stratified newtonian flow calculations by the boundary element method

A boundary integral equation formulation is used to model the stratified flow of two Newtonian viscous liquids, in which the geometrical detail of the interface between the layers is not known in advance. The technique is tested by comparing predictions with the results of previous finite element solutions, and found to perform well. Finally, the method is used to examine the two-layer jet theory of Tanner (1980) as a means of simplifying the modelling of complex extrudate swell problems.     

Effects of second language study of phonemic discrimination and auditory event-related potentials in adults

This study was designed to investigate the effects of acquisition of a second language on auditory even-related brain potentials and discrimination of foreign language phonemes by 36 women (ages 18 to 47 years), and 25 men (ages 18 to 36 years) and of varying linguistic background, in response to synthetic versions of Japanese phonemes. Subjects were subsequently tested on discrimination between spoken Japanese phonemes. Analysis indicated that the men and women differed in phonological processing and in the way acquisition of the second language affected phonological processing.     

Adsorption of Pentane Insoluble Organic Matter from Oilsands Bitumen onto Clay Surfaces

The effectiveness of commercial oilsands separation processes relies on the water wettability of the solids. Consequently, the interaction between the mineral and organic matter types present in oilsands is of interest. In this work, we report results related to the adsorption of a pentane insoluble fraction from bitumen on kaolinite and illite, the major clay types present in oilsands. We determined adsorption from toluene solution by illite and kaolinite and use a combination of spectroscopic techniques to probe the organic coated clay surfaces to different depths. The results are compared with similar data for equivalent natural fractions from oilsands.     

Controlling baseline trend in single-case research.

School psychologists commonly conduct interventions for individual students and evaluate their success through single-case research designs, most of which include a baseline observation period. However, concluding intervention effectiveness from a single-case design is problematic when pronounced baseline trend is evident. With positive baseline trend, interpretation of the measured mean difference between phases is ambiguous, and an invalid interpretation is probable. Although an adequate method for controlling baseline trend exists, it is rarely applied in published studies. This article seeks wider application of baseline trend control by describing a modified technique that blends more easily with visual analysis. A second goal of this article is to encourage better informed use of baseline trend control, by empirically demonstrating its need in published studies, and its impact on R2 effect sizes and on autocorrelation. Finally, baseline trend control is combined with elimination of autocorrelation, for results that can withstand the scrutiny of the broader research community. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eat smart! Workplace Cafeteria Program evaluation of the nutrition component.

PURPOSE: The nutrition component of the Eat Smart! Workplace Cafeteria Program (ESWCP) in a hospital was evaluated. We assessed staff's frequency of visits to and purchases in the hospital cafeteria, attitudes about the program, short-term eating behaviour change, and suggestions to improve the ESWCP. METHODS: Questionnaires were sent to hospital staff members who were not on leave (n=504). Dillman's Tailored Design Method was used to design and implement the survey. Four mail-outs were used and yielded a 51% response rate. RESULTS: Eighty-seven percent of respondents visited the hospital cafeteria at least once a week in an average seven-day week, and 69% purchased one to five meals or snacks there each week. Eighty-six percent of respondents said that they were aware of the hospital's program. Notices on cafeteria tables were the primary method of learning about the program (67%). Reported program benefits included increased knowledge about healthy eating, convenience of having healthy foods in the cafeteria, and increased energy. CONCLUSION: Many respondents were aware of the program, provided positive comments about it, and reported positive changes in eating habits. However, future observational research is warranted to note foods served and sold before and after program implementation, as well as to examine whether results can be generalized to other settings.