Predictive behavior. Some aspects based on an ecological orientation.

Genetic variation in behavioral traits allows organisms to respond and adapt to environmental challenges. Genetic variation in behavior is often affected by many genes and thus has a complex genetic basis. Inversions, the reorientation of genes along the chromosome, tightly link genetic variants together because they suppress recombination. Therefore, inversions are believed to have a major impact on phenotypic variation because they combine the effects of multiple genes, which can pleiotropically alter multiple aspects of behavior. This study investigates how the inversion In(2L)t, found in Drosophila melanogaster populations around the world, impacts different aspects of behavior in an environment-sensitive manner. We test the activity, foraging, and startle-induced behavior of flies with different In(2L)t genotypes across sex and temperatures. We observe that Drosophila homozygous for In(2L)t sleep less frequently, spend more time away from a food source, and have a longer duration of startle response. Additionally, the impacts of In(2L)t on aspects of behavior can be sex-specific and are largely consistent across temperatures. Taken together, our research demonstrates that inversions can regulate aspects of behavior, and suggests hypotheses explaining the distribution of In(2L)t across space and time.

Behavior↗

PubMed1995

Methodological and statistical considerations for exercise-related hormone evaluations.

Improvements in laboratory techniques have allowed research related to exercise endocrinology to flourish. The emerging literature, however, is often inconsistent and contradictory. The discrepancies in research findings are possibly the result of poor control of confounding variables and/or inappropriate methodologies or analyses. Environmental and pretesting behavioural conditions must be standardised to minimise the influence of variables not directly related to the investigation. Environmental temperature and relative humidity, alcohol, caffeine and nicotine intake, prandial state, sleep deprivation and previous exercise can each alter hormonal responses to exercise. Both prescription and over-the-counter medications can also modify normal hormonal secretions thereby confusing exercise-induced findings. Specimen collection and analysis procedures must be controlled carefully. Changes in plasma volume related to postural changes or tourniquet-induced stasis can confound attempts to isolate exercise-related endocrine responses. The established circadian and rhythmical variations characteristic of many hormones need to be controlled. The specimen selection (plasma, serum, urine, etc), collection, storage and analysis procedures should be carefully planned and evaluated. The magnitude of haemolysis, analytical and biological variation must also be monitored. Isolating the hormonal perturbations resulting from a particular exercise variable can be very difficult. Exercise intensity, duration, mode, frequency and volume may each have specific effects on the endocrine changes seen with exercise and training. Furthermore, hormonal responses to exercise are dependent upon initial training status and fitness level. The statistical procedures and data presentation options selected to convey experimental findings can bias experimental results. The descriptive and inferential statistics to be used for data analysis should be preplanned and consistent with the underlying assumptions of the analytical procedure. Careful consideration should be given to the biological relevance of statistically significant findings. In some cases, data transformations (e.g. absolute vs relative changes, logarithmic) should be considered for analysis or presentation. Given the individual nature of hormonal responses to exercise, emphasis should be placed presenting individual data. Other considerations, including age, sex, racial origin and disease conditions need to be controlled for when trying to examine exercise-induced hormone changes.

Behavior↗

PubMed1995

The self-employment option for people with disabilities: a case study of 'AHVA' desk top publishing company.

From the above results of the evaluation survey it can be concluded that the participants of the 'AHVA' desktop publishing company, who are with multiple and physical disabilities and who have initiated and run their own enterprise, perceived their first year of operation as beneficial. They mastered new technical skills, learned new work-related behaviours, expanded their interpersonal competencies and felt personal growth. They all developed high motivation to make their operation successful. The case study of 'AHVA' desktop publishing company, initiated and run by a group of multiply and physically disable persons, is unique and demonstrates the positive trend for the future. It is an example of personal and group commitment to build a competitive enterprise. It is self determination rather than the actual outcome of services provided, that is the driving force behind their efforts. The team members demonstrated that persons with disabilities can indeed take charge of their lives, be masters of their own destinies, and lead a productive and meaningful life. Here, inclusion is not a one-sided process in which service providers and rehabilitation experts try to integrate persons with disabilities into the community and regular employment. Inclusion is to integrate persons with disabilities into the community and regular employment. Inclusion is achieved here by the self initiative of a group of persons with disabilities. They have created an extraordinary enterprise according to their own special needs. Non-disabled people interact with them on an equal level, as partners in a business, sharing mutual interests of quality production.(ABSTRACT TRUNCATED AT 250 WORDS)

Behavior↗