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Naturalistic Conditions (naturalistic + condition)
Selected AbstractsHow many well vs. unwell days can you expect over 10 years, once you become depressed?ACTA PSYCHIATRICA SCANDINAVICA, Issue 4 2009T. A. Furukawa Objective:, Prognostic studies of major depression have mainly focused on episode remission and relapse, and only a limited number of studies have examined long-term course of depressive symptomatology at threshold and subthreshold levels. Method:, The Group for Longitudinal Affective Disorders Study has conducted prospective serial assessments of a cohort of heretofore untreated major depressive episodes for 10 years under naturalistic conditions. Results:, Of the 94 patients in the cohort, the follow-up rate was 70% of the 11 280 person-months. Around 77% of the follow-up months were spent in euthymia, 16% in subthreshold depression and 7% in major depression. Duration of the index episode before reaching recovery was the only significant predictor of the ensuing well time. Conclusion:, On average, patients with major depression starting treatment today may expect to spend three quarters of the next decade in euthymia but the remaining one quarter in subthrehold or threshold depression. [source] Direct and indirect effects of the introduced toad Bufo marinus (Anura: Bufonidae) on populations of native anuran larvae in AustraliaECOGRAPHY, Issue 3 2000Michael R. Crossland Introduced species are frequently believed to have adverse effects on native biota and ecosystems. However, much of our knowledge of the ecological impacts of introduced species is anecdotal, and the mechanisms controlling these effects are often poorly understood. I used replicated artificial pond experiments to investigate the impact of eggs and hatchlings of the introduced toad Bufo marinus on populations of native anuran larvae (Limnodynastes ornatus and Litoria rubella) in Australia. Bufo marinus eggs and hatchlings are highly toxic to predatory native tadpoles. Under naturalistic conditions, populations of predatory L. ornatus tadpoles experienced significantly reduced survival when exposed to Bufo eggs and hatchlings. The impact of Bufo on L. ornatus survival was positively correlated with Bufo density. However, the toxic effects of Bufo on L. ornatus indirectly facilitated the survival of later-breeding L. rubella by altering predator-prey interactions between L. ornatus and L. rubella. Limnodynastes ornatus tadpoles are voracious predators of L. rubella eggs and hatchlings. Consequently, the negative impact of Bufo on populations of L. ornatus tadpoles reduced the intensity of predation by L. ornatus tadpoles on L. rubella eggs and hatchlings, thereby increasing L. rubella survival. The results demonstrate that B. marinus plays an important role in structuring native larval anuran communities via direct and indirect mechanisms, and that Bufo may have both negative and positive effects on populations of native anuran larvae. As far as I am aware, these are the first quantitative data to demonstrate that introduced fauna may affect populations of native biota via toxic effects. [source] Relationship Between Perceived Clothing Comfort and Exam PerformanceFAMILY & CONSUMER SCIENCES RESEARCH JOURNAL, Issue 4 2005Rick Bell Recent controlled laboratory studies have shown an effect of clothing comfort on cognitive performance. To test this relationship under naturalistic conditions, student scores on statistics exams were compared with comfort ratings. Prior to the exam, students rated their confidence in taking the exam, number of hours studied, comfort level, type of clothes being worn, and other relevant variables. To maintain naturalistic conditions, clothing was not manipulated but was self-selected. Controlling for other variables associated with exam performance, multiple regression results indicated a significant positive relationship between comfort ratings and exam scores, with the model explaining 48% of the variance in exam scores R2 = .48). As expected, the more formal the attire, the lower the comfort rating of that attire and the lower the exam score. This study provides further evidence of a relationship between perceived clothing comfort and cognitive performance. [source] Experimental infection magnifies inbreeding depression in house miceJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2008P. ILMONEN Abstract It is often assumed that inbreeding reduces resistance to pathogens, yet there are few experimental tests of this idea in vertebrates, and no tests for the effects of moderate levels of inbreeding more commonly found in nature. We mated wild-derived mice with siblings or first cousins and compared the resistance of their offspring to Salmonella infection with outbred controls under laboratory and seminatural conditions. In the laboratory, full-sib inbreeding reduced resistance to Salmonella and survivorship, whereas first-cousin inbreeding had no detectable effects. In competitive population enclosures, we found that first-cousin inbreeding reduced male fitness by 57% in infected vs. only 34% in noninfected control populations. Our study provides experimental evidence that inbreeding reduces resistance and ability to survive pathogenic infection, and moreover, it shows that even moderate inbreeding can cause significant fitness declines under naturalistic conditions of social stress, and especially with exposure to infectious agents. [source] The circadian and homeostatic modulation of sleep pressure during wakefulness differs between morning and evening chronotypesJOURNAL OF SLEEP RESEARCH, Issue 4 2003Jacques Taillard Summary The purpose of this study was to evaluate homeostatic and circadian sleep process in ,larks' and ,owls' under daily life conditions. Core body temperature, subjective sleepiness and waking electroencephalogram (EEG) theta,alpha activity (6.25,9 Hz) were assessed in 18 healthy men (nine morning and nine evening chronotypes, 21.4 ± 1.9 years) during a 36-h constant routine that followed a week of a normal ,working' sleep,wake schedule (bedtime: 23.30 h, wake time: 07.30 h). The phase of the circadian rhythm of temperature and sleepiness occurred respectively, 1.5 h (P = 0.01) and 2 h (P = 0.009) later in evening- than in morning-type subjects. Only morning-type subjects showed a bimodal rhythm of sleep,wake propensity. The buildup of subjective sleepiness, as quantified by linear regression, was slower in evening than in morning types (P = 0.04). The time course of EEG theta,alpha activity of both chronotypes could be closely fitted by an exponential curve. The time constant of evening types was longer than that of morning types (P = 0.03), indicating a slower increase in sleep pressure during extended wakefulness. These results suggest that both the circadian signal and the kinetics of sleep pressure buildup differ between the two chronotypes even under prior naturalistic conditions mimicking the usual working day. [source] Chest pain is inversely associated with blood pressure during exercise among individuals being assessed for coronary heart diseasePSYCHOPHYSIOLOGY, Issue 2 2007Blaine Ditto Abstract Acute and chronic increases in blood pressure have been related to decreases in pain perception. This phenomenon has been studied primarily using acute experimental pain stimuli. To extend the literature to naturalistic pain and in particular the problem of silent cardiac ischemia, this study examined the relationship between blood pressure and chest pain during exercise stress testing. Nine hundred seven (425 men, 482 women) individuals undergoing exercise stress testing for diagnosis of possible myocardial ischemia completed the McGill Pain Questionnaire (MPQ) immediately afterward and other questionnaires before and after testing. Blood pressure was measured before, during, and after exercise. Systolic blood pressure at the end of exercise was inversely related to a number of measures of pain such as total score on the MPQ. The relationship could not be explained by individual differences in exercise duration, medication use, sex, or other measured variable. In sum, the inverse relationship between blood pressure and sensitivity to pain that has been observed in other populations in experimental and naturalistic conditions was observed for chest pain during exercise. Blood pressure may contribute to episodes of silent ischemia. [source] | |||||||||||||