Quality of life in adolescents with a disability and their parents: the mediating role of social support and resilience

The aim of this study was to test whether the effect of the pile-up of demands associated with a disability on quality of life, was mediated by resilience, quantity and quality of social support for adolescents with a disability and their parents. One hundred and thirty two parents, 90 mothers and 42 fathers and 111 adolescents, aged between 16 and 24 years completed measures of the pile-up of demands, social support, resilience and quality of life. Structural equation modeling with the bootstrap resampling method showed that the impact of the disability of their son/daughter on the quality of life of the parents was fully mediated through the parents' resilience and the quantity of social support and that resilience, however only partly, mediates the effect of adaptive skills on the quality of life of the adolescents with a disability. Limitations of the study and clinical implications are discussed

Influence of sperm-oocyte coincubation period on porcine in vitro fertilization (IVF) efficiency

A major obstacle for successful in vitro production of porcine embryos is the polyspermic fertilization. One possibility to reduce polyspermic penetration is decreasing the number of spermatozoa added to the fertilization medium. Unfortunately, the lower rate of polyspermy is accompanied by a reduced penetration rate. A short gamete coincubation period of 10 min has been described to obtain fertilization rates similar to 6 h of coincubation and may improve IVF efficiency (number of monospermic fertilized oocytes/total number inseminated) depending on sperm-oocyte ratio (Gil, 2007, Theriogenology, 67(3), 620–626). Here we demonstrate that the optimal coincubation period in our IVF conditions is between 10 min and 6 h. In vitro matured oocytes (n = 600) were inseminated with frozen-thawed epididymal semen with 600 spermatozoa per oocyte and coincubated for 2, 4 and 6 h. At 2 and 4 h post insemination (hpi), oocytes were vortexed and transferred to fertilization medium without spermatozoa. At 6 hpi, presumed zygotes of all groups were washed three times in culture medium and cultured. At 22 hpi, zygotes were fixed overnight and stained with Hoechst 33,342 for the assessment of fertilization and polyspermy. The IVF efficiency was higher for the 4 h group (40 ± 5%) than the 2 and 6 h group (19 ± 8% and 17 ± 5%). Between 4 and 6 h of gamete coincubation, the increase in the number of polyspermic oocytes was relatively higher than the increase in penetration rate (+39% vs. +15%), resulting in a decline in efficiency. (This study was supported by Research Foundation-Flanders)

Knowledge of AIDS, perceived risk of AIDS, and at-risk behaviors among older adults

By using a questionnaire derived from the Health Belief Model, this study examined older adults\u27 knowledge of AIDS, perceptions of risk to AIDS, and at-risk behaviors. A total of 166 questionnaires were received from the EXCELL and Senior Adult Theater Group members actively enrolled at the University of Nevada, Las Vegas. The results indicated the respondents were knowledgeable about the transmission and seriousness of AIDS but were less knowledgeable about AIDS transmission through casual contact and the medical aspects of AIDS. Although they recognized the seriousness of AIDS, they generally do not believe that they are susceptible to this disease. Most did not think protecting themselves from AIDS would be particularly burdensome and they perceived safe sexual practices to be effective in preventing HIV transmission. Overall, this sample does not exhibit activities that would increase their chances in acquiring the AIDS virus and their use of condoms was low

Interpersonal influence in families: development and psychometric evaluation of the influence in families questionnaire

The objective of this article was to develop and psychometrically evaluate a self-report instrument that would assess interpersonal influence in families. The Influence in Families Questionnaire (IFQ) was developed as a 16-item scale which assesses both positive and negative influence. The IFQ and its sub-scales, when administered to a sample of 581 adolescents and Young adults, showed high internal consistency and exhibited a promising pattern of convergent, divergent and criterion validity in relation to relevant criteria such as impact messages, family and attachment relationships and interpersonal sense of control. Overall, these results suggest that the IFQ is a useful instrument for measuring interpersonal influence within families

Porcine oocyte maturation in vitro : role of cAMP and oocyte-secreted factors: a practical approach

Polyspermy or the penetration of more than one sperm cell remains a problem during porcine in vitro fertilization (IVF). After in vitro culture of porcine zygotes, only a low percentage of blastocysts develop and their quality is inferior to that of in vivo derived blastocysts. It is unknown whether the cytoplasmic maturation of the oocyte is sufficiently sustained in current in vitro maturation (IVM) procedures. The complex interplay between oocyte and cumulus cells during IVM is a key factor in this process. By focusing on this bidirectional communication, it is possible to control the coordination of cumulus expansion, and nuclear and cytoplasmic maturation during IVM to some extent. Therefore, this review focuses on the regulatory mechanisms between oocytes and cumulus cells to further the development of new in vitro embryo production (IVP) procedures, resulting in less polyspermy and improved oocyte developmental potential. Specifically, we focused on the involvement of cAMP in maturation regulation and function of oocyte-secreted factors (OSFs) in the bidirectional regulatory loop between oocyte and cumulus cells. Our studies suggest that maintaining high cAMP levels in the oocyte during the first half of IVM sustained improved oocyte maturation, resulting in an enhanced response after IVF and cumulus matrix disassembly. Recent research indicated that the addition of OSFs during IVM enhanced the developmental competence of small follicle-derived oocytes, which was stimulated by epidermal growth factor (EGF) via developing EGF-receptor signaling

Comparison of five different methods to assess the concentration of boar semen

Both for research and practical purposes, accurate and repeatable methods are required to assess the concentration of boar semen samples. Since the method which is used may influence the results considerably, the aim of the present study was to compare 5 frequently used techniques to determine boar semen concentration. Fifty ejaculates were collected from 37 different boars at an artificial insemination centre. Subsequently, each ejaculate was analyzed for sperm concentration by means of 2 different types of colorimeters (Colorimeter 1: Model 252, Sherwood Scientific Ltd, Cambridge, UK; Colorimeter 2: Ciba-Corning, Schippers, Bladel, The Netherlands), the Burker counting chamber (golden standard), and the Hamilton Thorne Analyzer (Ceros 42.1) using 2 types of Leja chambers (the 'former' and the 'recently developed'). Each ejaculate was assessed 5 times with each of the 5 methods, and the repeatability, expressed by coefficient of variation (CV), was determined for each method. The different methods were compared using Pearson's correlations and limits of agreement. The colorimeters yielded the lowest CV's (both 3.7%), while the former Leja chamber resulted in the highest CV (12.4%). Moreover, significant (P0.71) were found between the results obtained by the different methods. The limits of agreement plots showed that none of the methods consistently over- or underestimated the sperm concentrations when compared to the Burker chamber, although there was a tendency toward higher over- or underestimation in highly concentrated sperm samples. Based on our results, there were no major differences in the assessment of sperm concentration between the evaluated methods. The choice of method used in a laboratory could therefore be based on factors such as cost, number of samples to be assessed and practical use, without thereby negatively affecting the validity of the results thus obtained

Measuring User Beliefs and Attitudes towards Conceptual Schemas: Tentative Factor and Structural Equation Model

Human factors research in conceptual modeling is scarce. Recently, quality assurance frameworks, methods and tools for conceptual schemas have received increased research attention, but the perception of quality by schema users has largely been ignored in this stream of research. This paper proposes a tentative model of user beliefs and attitudes towards the quality of conceptual schemas. The proposed model is original in the sense that it includes both perceived semantic quality and perceived pragmatic quality measures. The paper also presents a new measurement instrument for the perceived semantic quality of conceptual schemas. This instrument was used in a classroom experiment that tested the proposed user beliefs and attitudes model. It was shown that the perceived semantic quality of a schema is directly related to its perceived usefulness and perceived ease of use and indirectly to the user satisfaction with the schema