Rationale and study aims: Persons with mild cognitive impairment (MCI) experience declines in everyday functioning and cognitive performance greater than what is experienced in normal aging but less than that of dementia. Daily stress and daily memory complaints associated with cognitive deficits may contribute to greater psychological distress in the day-to-day experiences of persons with MCI. However, research examining the occurrence of daily stressors, daily memory complaints and psychological distress in MCI is limited, and it is not clear how the daily processes of stress and affect in persons with MCI compare to cognitively healthy older adults. This dissertation examined the occurrence of daily stressors, daily memory complaints, retrospective and daily well-being in persons with MCI compared to cognitively healthy controls. Main analyses examined whether daily stressors and daily memory complaints were associated with worse daily affect in MCI participants compared to controls, and whether increased daily stress was associated with a greater number of memory complaints. Methods: The study used a short-term repeated measures design, and included MCI and control participants recruited from a university-based memory clinic. The interviews consisted of a baseline interview and up to eight consecutive days of brief daily phone interviews. The interviews included both retrospective and daily measures of psychological well-being, daily stressors, daily memory complaints, and open-ended questions about daily experiences. Results: Persons with MCI reported a greater number of daily memory complaints and worse psychological distress, as measured by both retrospective and daily reports. There were no significant differences between MCI and control participants, however, in the frequency of daily stressors. In both unadjusted and adjusted analyses, on days when a participant reported more daily stressors, they had higher negative affect. The stress-negative affect relationship was stronger for MCI participants compared to controls. MCI and control participants who reported more memory complaints, on average, had higher negative affect. Discussion: Daily stressors were disproportionally associated with greater psychological distress in MCI participants as compared to cognitively healthy controls. Interventions targeting the potential distress associated with daily life may be beneficial for psychological well-being in persons with MCI. Future research should examine other potential mechanisms of distress in daily lives of persons with MCI in order to inform relatives and caregivers of persons with MCI, clinicians who give diagnoses to their patients, and individuals providing community support for individuals living with MCI.

Examinations of stress in relation to adolescent mental health have not often utilized a comprehensive definition of psychological functioning. Recent literature has found support for the importance of examining optimal psychological functioning as the presence of high life satisfaction in addition to low psychopathology (Antamarian, Huebner, Hills, & Valois, 2011; Suldo & Shaffer, 2008). Most research on stress has focused on either major stressful events or chronic environmental stressors; further research is needed on the psychological model of stress, which conceptualizes stress as involving both environmental events and one's cognitive appraisals of the stressor. The current longitudinal study determined how multiple types of stress (accumulation of stressful life events, chronic stressors in social relationships, global perceived stress level) are associated with mental health (i.e., psychopathology and life satisfaction) over a one year period. Additionally, this study explored whether perceptions of social support from various sources (i.e., parents, classmates, teachers) act as a protective factor in the relationship between stress and later mental health outcomes. Data collection for Time 1 occurred in the Fall 2010, and was part of a larger on-going research project involving 500 students from grade 9 - 11. Time 2 data collection occurred during the Fall of 2011 and included 425 of those students, now in grades 10-12. Analyses included multiple regression to examine both the overall contribution of stress on mental health outcomes (life satisfaction, internalizing psychopathology, externalizing psychopathology) as well as the unique contributions of various types of stress. Additional regression analyses explored whether social support from various sources acts as a buffer for students that experience stress from later increases in psychopathology or declines in life satisfaction. Results revealed that the combination of Time 1 mental health variables and all forms of initial stress accounted for the most amount of variance (45%) in Time 2 internalizing problems and the least amount of variance in Time 2 externalizing problems (13%). In all cases, the largest predictor of Time 2 mental health was initial levels of mental health. The only stressor that appeared as a unique predictor of Time 2 mental health was stress in the student-teacher relationship, which accounted for a significant amount of variance in Time 2 externalizing problems. Further regression analyses found that parent and peer support were critical in predicting later mental health (i.e., exerted main effects). These analyses identified trends in the data in which parent and teacher support acted as buffers in the relationships between some forms of stress and later mental health. Implications for school psychologists and future directions for research are discussed.

The purpose of this study was to investigate the influence of hostile attribution style (HAS) on the processes linking job stressors and CWB. Self and peer data were collected via online questionnaires from employed participants recruited from undergraduate classes and non-student employees. Using data from 147 dyads of employees and coworkers, the effects of HAS on three areas were examined: the influence of HAS on the appraisal of psychosocial (incivility, interactional justice, and interpersonal conflict) and nonsocial (organizational constraints and workload) stressors; HAS as a moderator of the link between stressors and CWB; and HAS as mediator of the link between CWB and the individual difference variables of negative affectivity (NA), trait anger, and Machiavellianism. Regarding appraisals, HAS was more strongly related to psychosocial stressors than to workload (nonsocial stressor). However, results regarding the comparisons of the HAS-psychosocial stressor correlations with the HAS-organizational constraints (nonsocial stressor) correlations were mixed. Moreover, contrary to what was hypothesized, correlations of HAS with interpersonal constraints and job context constraints were not significantly different in magnitude. HAS was shown to moderate the relationship between CWB and the stressors of interpersonal conflict and organizational constraints. Individuals high on HAS engaged in more CWB when stressors were high, whereas individuals low on HAS engaged in low levels of CWB overall. HAS partially mediated the relationship between NA and CWB, in addition to the relationship between trait anger and CWB. It fully mediated the relationship between Machiavellianism and CWB. The influence of Machiavellianism on the occupational stress process also was explored. It was expected that high Machiavellians would appraise and respond to stressors in a negative fashion. However, contrary to what was expected, Machiavellianism was positively associated with informational justice and negatively related to incivility and CWB. Furthermore, it was negatively associated with NA and HAS. An alternative explanation for the results regarding Machiavellianism was presented. Although all hypotheses regarding the effects of HAS were partially supported, results of this study were generally demonstrative of the merits of including attributional processes (i.e., hostile attribution style) in CWB research within the occupational stress framework.

This exploratory study explores how management control systems influence job stressors. More specifically, this study seeks to unravel the mechanisms by which budget and KPI controls influence job stressors. In our study we use the well-established Job Demand - Job Control - Job Support Model to compare previous research on job stressors with our case study. We interview Controllers and Managers at a manufacturing company within the industrial industry. Data was collected through semi-structured interviews and analysed through thematic content analysis. Our study discovers various combinations of how budget and KPI controls influence job stressors. We unravel four mechanisms by which budget and KPI controls influence job stressors. The identified mechanisms are Involvement, Comparability, Predictability, and Rationalization, in where involvement is shown to be most prominent.

Across the world, job insecurity plays a critical role in organisations. This insecurity affects not only the individual, but also the organisation. In South Africa, the Employment Equity Act (No. 55 of 1998), and the Broad-Based Socio-Economic Empowerment Charter for the South African Mining Industry (Mining Charter), brought changes to the mining industry policies and decision-making process in terms of selection and recruitment, which could in turn lead to feelings of job insecurity. Other factors such as the availability of gold left to be mined, restructuring and strikes increase work-related stress. The objectives of this study were to investigate the role of job insecurity in predicting health related behaviours, and to determine whether coping moderates the effect of job insecurity on health behaviours for a group of managers in a South African gold mining company. A cross-sectional design was used. The study population (n = 206) consisted of managers in a gold mining company in South Africa The Job Insecurity Scale, Cybernetic Coping Scale and Health Complaints Questionnaire were used as measuring instruments. Descriptive statistics (e.g. means, standard deviations and kurtosis) were used to analyse the data. Hierarchical multiple regression analysis was used to test for the hypothesized moderating effect of coping on the relation between job insecurity and health-related behaviours. The results of the regression analyses showed that qualitative job insecurity was a significant predictor of health complaints. Qualitative job insecurity was also a significant predictor of health complaints in employees who smoked cigarettes and drank alcohol, and exercised at least once a week. Quantitative job insecurity did not play a role in predicting health-related behaviour. Coping did not moderate the effects of job insecurity for employees with health complaints. Rather, it is suggested that using negative coping behaviours may actually contribute to health complaints. Recommendations for future research are made. / Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2006.

Freshwater ecosystem degradation in the Amazon and Orinoco river basins is increasing due to rising human population numbers, and large water development projects. Therefore, monitoring ecosystem condition in these rivers of high biodiversity is of global conservation importance. This dissertation evaluated the potential of using river dolphins as indicators of ecosystem condition in large tropical rivers of South America. First, population estimates of river dolphins were obtained by line-strip transect surveys and mark-recapture methods on photo-identifications. Using this information, I identified critical habitat, hotspots, and areas of concern for river dolphins, as well as the relationship between dolphin density and group size estimates with ecological features. Second, I evaluated the relationship between dolphin estimates and human stressors. Higher densities of dolphins occurred in rivers with low indices of overall freshwater degradation, such as rivers with high water quality and the lowest human population numbers. Thus, dolphin density estimates seem to be good indicators of freshwater ecosystem degradation in the Amazon and Orinoco basins. These top predators not only are indicator species, but also have the potential to act as flagship and sentinel species, indicating freshwater ecosystem degradation and stimulating conservation action. This dissertation highlights the large changes in the Amazon and Orinoco that are approaching fast. Indicator, flagship and sentinel species can become science-based conservation tools not to only document freshwater ecosystem degradation, but to raise awareness about broader implications of human stressors on biodiversity and river systems.

Metodika: Tyrimas buvo atliekamas 2012 metų rugsėjo-gruodžio mėnesiais Mykolo Romerio universitete (MRU). Tyrimui atlikti naudotas apklausos metodas, duomenų rinkimo instrumentu pasirinktas klausimynas raštu. Tyrimo imtį sudarė atsitiktiniu būdu atrinkti MRU studentai. MRU populiacija yra 22 000, taikant 5 proc. paklaidą apskaičiuota, kad siekiant gauti statistiškai reikšmingus rezultatus reikia apklausti 519 studentų. Iš viso užpildyta 509 klausimynai, 10 klausimynų buvo sugadinti arba negražinti. Apklausti visų kursų studentai – tiek bakalaurai, tiek magistrantai. Tiriamųjų amžius – nuo 19 iki 35 metų. Tyrime dalyvavo 369 (72,5 proc.) moterys ir 140 (27,5 proc.) vyrų. Tyrimo organizavimas buvo grindžiamas savanoriškumo ir genoriškumo principais. Rezultatų apdorojimui buvo naudojamas programinis statistinių duomenų paketas SPSS 20.0. Tyrimo duomenys laikyti statistiškai patikimais, jei p<0,05. Rezultatai: Stresas, tai organizmo būsena, kuri atsiranda dėl įvykių, kuriuos asmuo laiko grėsmingais ir sunkiai įveikiamais. Stresoriai skirstomi į tris veiksnių grupes: fizinius, socialinius ir psichologinius. Stresas didina fizinės ir psichinės sveikatos sutrikimų riziką ir mažina atsparumą neigiamam aplinkos poveikiui. Dažniausiai streso įveikimo strategijos skirstomos į problemą ir į emocijas orientuotus įveikimo būdus. Dauguma MRU studentų (90 proc.) patiria stresą, moterys statistiškai reikšmingai dažniau už vyrus. Pagrindiniai studentų stresoriai yra egzaminai ir atsiskaitymai... [toliau žr. visą tekstą] / Methods: investigation was carried out September 2012 to December 2012 in the university of Mykolas Romeris. For investigation was used survey method, data collection instrument selected written questionnaire. The investigation consists of randomly selected students from university of Mykolas Romeris. The population of university Mykolas Romeris is 22 000, with a 5 percent error calculatedin order to obtain statistically significant results 519 students should be surveyed. Completing a total of 509 questionnaire, 10 questionnaire has been damaged or does not return. Interviewed all of the courses students - both undergraduate and postgraduate students. Investigated age of students is from 19 till 35 years old. Investigation included 369 (72,5 percent) women and 140 (27,5 percent) men. Organization of the investigation was based on a voluntary and benevolence principles. Proccesing of the results consisted of statistical software package for data SPSS 20.0 Survey data was considered statistically reliable if p < 0.05 Results: stress is the body's reacton caused by events that persons find sinister and difficult to overcome. Stressors are devided into three groups of factors: physical, social and psychological. Stress increases physical and mental health risks and reduces resistance to environmental stress. Often stress coping strategies are devided to problems and emotion oriented ways of overcoming. Most students (90 percent) from university of Mykolas Romeris experience... [to full text]

The current study developed a paleolimnological approach to assess changes in diatom assemblages (class Bacillariophyceae) from present-day lake sediments in comparison to those deposited before significant human impact (ca. pre-1850) from 51 Halifax (Nova Scotia, Canada) region lakes in conjunction with a regional diatom-based transfer functions for pH and total phosphorus. All 51 lakes showed changes in diatom assemblages between the present-day and pre-industrial assemblages that was greater than would be expected (i.e. similarity between ‘top’ and ‘bottom’ samples was much less than the similarities within triplicate ‘top’ and ‘bottom’ samples). To help identify the most important environmental stressors impacting diatom assemblages in these lakes, diatom-based reconstructions of inferred changes in pH (DI-pH) and total phosphorus (DI-TP) that were greater than the Root Mean Squared Error (RMSE) of the respective inference models were reconstructed for each of the 51 lakes. For example, a decrease in DI-pH greater than the RMSE of the pH model would be a strong indication of recent acidification, whereas an increase in DI-TP greater than the RMSE of the model indicates nutrient enrichment. Based on this approach, 4% of the lakes are showing acidification-related trends occurring in lakes with low pre-industrial pH values and relatively undisturbed watersheds. Almost 14% of the study lakes have been impacted by nutrients and characterized by watershed development and high concentrations of TP. Approximately 4% of lakes showed oligotrophication and acidification. Diatom assemblages from almost 20% of the study lakes that were relatively unimpacted by the afore-listed environmental stressors show trends consistent with climate warming. These lakes show an increase in DI-pH greater than the RMSE of the inference model, and floristic changes typically showed a decrease in the relative abundance of Aulacoseira distans paralleled with increase in Cyclotella stelligera and other planktonic diatoms in the modern sediments. In addition, Diatoma tenue and Diploneis parma, diatoms tolerant of high conductivity, increased in 45% of the study lakes suggesting road salt as an additional stressor. This thesis provides a rapid paleolimnological-based technique to assess regional water-quality changes, and further demonstrates the complexity of ecological changes within freshwater resources. / Thesis (Master, Biology) -- Queen's University, 2009-09-10 15:18:07.01

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Interactions between multiple anthropogenic stressors can have unexpected synergistic or antagonistic effects, making it difficult to predict their combined effect using single stressor studies. The interaction between invasive consumers and nutrient enrichment is particularly important as both of these stressors frequently co-occur and their respective bottom-up and top-down effects have the potential to interact across multiple trophic levels. We conducted a mesocosm experiment that crossed an increasing nutrient addition gradient against an increasing zebra mussel invasion gradient. Native zooplankton communities were added to the mesocosms, and after three months we examined how the single stressor effects on available resources and the zooplankton community were altered by their multiple stressor interaction. Added nutrients had no effect on primary producer abundance, but increased the abundance and dominance of the top consumer, which likely increased predation pressure on the producers and so prevented their response to increased nutrients. Zebra mussels reduced total phytoplankton abundance by ~75%, rotifer abundance by ~80%, and shifted communities towards dominance of cladocerans and adult/juvenile copepods. When combined, the top-down control exerted by the mussels interacted antagonistically to prevent any bottom-up influence of nutrient enrichment on the zooplankton community. These results provide insight into the potential outcomes of nutrient and invasive consumer stressor interactions, and illustrate the need for researchers to consider single stressor problems in a multiple stressor context. / Thesis (Master, Biology) -- Queen's University, 2014-01-31 15:20:15.387