Research suggests that Internet and cell phone overuse may result in lower levels of social skills and encourage isolation from peers. Less clear is whether the duration of computer-mediated communication (CMC) influences adolescent perception of their social skills competency or emotional health. This research was guided by the social cognitive theory, which suggests that social self-efficacy (SSE), the belief that they have the skills to engage successfully with others in conversation and social activities, develops from mastery experiences that regulate thought, motivation, and action. This quantitative cross-sectional survey design utilized a convenience sample of 49 adolescents ages 11-19, living in Austin County, TX, to examine the impact of CMC duration on adolescent SSE, social anxiety, and depression. Regression analyses indicated CMC duration did not significantly affect SSE, social anxiety, or depression at the p <. 05 level. Computer-mediated communication duration did influence SSE at the p = .07 level, suggesting a trend toward statistical significance. Post hoc analysis revealed a significant interaction at the p < .05 level when CMC restriction severity was tested as a moderator in the CMC duration-SSE relationship. These findings suggest that the interaction between CMC duration and restrictions may influence social self-efficacy. Additional research on the relationship between CMC and adolescent psychosocial health would be helpful, particularly using larger and more generalizable samples. This study may inform the efforts of authority figures to adolescents, specifically, on the ways in which technological changes affect adolescent social development and will help to ensure that adolescents are safe, psychologically healthy, and able to maintain healthy relationships.

The effects of grazing and moisture availability on the competitive interactions of intermediate wheatgrass (Thinopyrum intermedium (Host) Barkw. & D.R. Dewey) and western wheatgrass (Pascopyrum smithii (Rhydb.) A. Love) were examined under a short-duration grazing system in central Utah. The fate of tiller cohorts was observed at approximately monthly intervals at the interface between patches of these two rhizomatous grasses and in monospecific stands. The effects of short-duration grazing, clipping of western wheatgrass following grazing to achieve levels of utilization equivalent to that of intermediate wheatgrass, irrigation, and removal of the competitor were assessed in terms of the recruitment, longevity, and mortality of ramets of both species. The effects of severance of clonal connections and defoliation on the performance of young shoots of both species were also studied. The tiller dynamics of the two species differed greatly. Maximum life span of intermediate wheatgrass tillers was approximately 18 months, while that of western wheatgrass tillers exceeded the 3.5-year observation period. Tiller turnover was higher in intermediate wheatgrass than in western wheatgrass. Defoliation tended to increase the mortality risk of intermediate wheatgrass ramets but not that of western wheatgrass ramets. Supplemental water had the opposite effect. Irrigation increased the probability of ramet survival for intermediate wheatgrass during the growing season but led to higher winter mortality for western wheatgrass ramets. During the four years of this study (1987-1990), western wheatgrass was the competitive dominant species. Recruitment of intermediate wheatgrass ramets at the interface was reduced compared to monospecific stands while that of western wheatgrass was enhanced. The mortality of intermediate wheatgrass tillers increased as a result of competition with western wheatgrass but only when plants were grazed. Competition had little effect on the mortality of western wheatgrass ramets. The competitive ability of intermediate wheatgrass versus western wheatgrass improved when both species were grazed heavily and when plants were irrigated.

This study was undertaken to determine the effect of oxygen absorber packets (OAP) (AGELESS Z.300 E) in improving the shelf-life of selected dried food products, including dried potato pearls, dried sliced apple, dried carrot, white rice, nonfat dry milk, all purpose flour, rolled oats, and wheat. Items were stored at four different temperatures (-20, 10, 21, and 29.5°C) over a period of 24 months with observations at 6-month intervals. Hunter colorimeter, thiobarbituric acid reactive substance (TBARS) germination rate, gluten weight, and volume were parameters used as quality indicators of various dried foods. Statistical analysis indicated a significant time and temperature effect for almost all the stored products. Storage at a high temperature (29.5°C) renders OAP ineffective in reducing browning during storage. Potato pearls, dried sliced apple, and dried carrot exhibit darkening by the first 6 months of storage at 29.5°C regardless of oxygen status of the container. White rice showed yellowing under the same conditions. Most of the dried food products that were stored at 10 and 21°C with or without oxygen absorber packets maintained their color as indicted by a relatively constant lightness reading (L*) over time. TBARS values rose in all stored food with increasing storage time, especially when the dried products were stored at higher temperature (29.5°C). Statistical analysis indicated a significant OAP effect in reducing TBARS concentration over time. Germination of wheat kernel was reduced to less than 80% after 24 months of storage at 29.5°C. However, when stored with oxygen absorber packets, germination was still 86%. Storage length and temperature are the primary factors that determine the quality of home-stored dried food items.

京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第20870号 / 経博第565号 / 新制||経||283(附属図書館) / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 西山 慶彦, 准教授 山田 憲, 准教授 高野 久紀 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM

Countries with unemployment insurance (UI) program can effectively conduct a labor market policy and observe the flow of unemployed-employed. But should we just hand UI over to anyone who has no job? Do individual response to the program in terms of their decision to work or to enjoy more leisure unanimously the same across leisure type characteristic individuals? In a heterogeneous constructed labor search market we derive that introduction of the UI program increases the wage gap between the different individuals when the program impacts the productivity of firm positively. In an empirical investigation of the impact of unemployment benefits on the duration of unemployment using a job search model, we specify a distribution of duration of unemployment that we estimate using maximum likelihood estimation and find that there is in the National Longitudinal Survey of Youth (NLSY 97) there are 3 types of individuals and the type of leisure individuals present an adverse response to the program: An increase in UI for the highest leisure type leads to a longer duration of unemployment. Whereas the lowest values of leisure do not tend to have an extended duration of unemployment from a positive change in UI. Finally, the response for the type 2 individuals is completely ambiguous as it could either see them having a prolonged duration of unemployment or a shortened period with no work. So a selective increase in unemployment insurance to those with a relatively low value of leisure may decrease the equilibrium rate of unemployment. The second part of the dissertation focuses on modeling money demand and shocks in Cote D'Ivoire for the period of 1960-2009. Unlike Drama and Yao (2010) our result suggests M1 is not in a long-run equilibrium with its determinants real income and expected inflation and therefore unstable. However, the broad definition M2 is cointegrated with its long-run determinants and it is therefore the most appropriate definition of money for the Cote D'Ivoire economy. As a consequence M2 can be used as an alternative to the interest rate as a long run monetary policy instrument.

Människor lämnar alla efter sig ett miljöavtryck när man inhandlar matvaror. Hur stort miljöavtryck man upplever att man lämnar efter sig är dock inte alltid korrekt. Syftet med studien var att undersöka om upplevelsen av en köprundas miljöavtryck påverkas särskilt av huruvida köprundan inleds med ett miljövänligt val eller avslutas med ett miljövänligt val. Detta för att få en bredare förståelse om kognitiva mekanismer som ligger till grund för miljörelaterat beteende. I denna kvantitativa studie så studerades psykologin i människors upplevelse av miljöpåverkan genom att undersöka hur miljömärkning påverkar upplevelsen av miljöavtryck från konsumentval. Studien undersökte ifall miljömärkta varor har större effekt på denna upplevelse om de märkta varorna inhandlas i början eller i slutet i en sekvens av inköp. Detta utfördes genom ett digitalt test som 32 deltagare (17 kvinnor, 15 män) vars ålder var mellan 22 och 63 år (M=32,31 år, SD=10,92) fick delta i och skattade sin miljöpåverkan som deltagarna tror att varorna hade under den fiktiva köprundan. Genom att undersöka ifall ordningen från första eller sista miljövalet har betydelse så får man en primacy eller en recency effekt. Denna studie indikerar på att under en köprunda när den avslutas med ett miljövänligt val så kommer människor uppleva att ens köprunda har lägre miljöavtryck i sin helhet. Studien visar alltså på en recency effekt samt duration neglect, däremot ingen primacy effekt. / Every single person who buys food products leave an environmental footprint. How big of an environmental footprint you feel you leave behind is not always accurate. The purpose of the study was to examine whether the experience of a shopping round's environmental footprint is particularly affected by whether the shopping round begins with an environmentally friendly choice or ends with an environmentally friendly choice. This is to gain a broader understanding of cognitive mechanisms which are the basis of environmental behaviour. In this quantitative study, the psychology of people's experience of environmental impact were studied by examining how environmental labelling affects the experience of environmental footprint from consumer choices. The study examines whether eco-labelled goods have a greater effect on this experience if the labelled goods are purchased at the beginning or at the end of a sequence of purchases. This is done through a digital test that 32 participants (17 women, 15 men) aged between 22 and 63 years (M=32,31 år, SD=10,92) can take part in where they estimate their environmental impact that the participants think the goods have had during the fictitious shopping round. By checking the order, if the first or last choice is important, you get a primacy or a recency effect. This study indicates that during a shopping spree when it ends with an environmentally friendly choice, people will experience that one's shopping spree has a lower environmental footprint as a whole. The study thus shows a recency effect and a duration neglect, but no primacy effect.

Rapid warming in the Arctic is highly impacting the cryosphere in the region, causing melting of the sea ice, retreat of glaciers and reduction in the snow cover. If suffering further temperature increase, the albedo of the region would reduce due to higher absorption of the solar radiation in snow-free areas. The variations in seasonal snow cover in Arctic regions can impact a lot of things including the ecosystem, biodiversity, hydrological cycle, and many other physical processes. Therefore, it is beneficial to have the knowledge of processes determining the snow distribution and to understand the trends and patterns of the seasonal snowcover.In this project, seasonal snow cover trends and patterns have been studied for a 30-year period from 1991 to 2020 using a newly developed reanalysis dataset called Copernicus Arctic Regional Reanalysis (CARRA). A validation of the CARRA data set has been done for the snow depth using point observation data from the Norwegian weather stations and a visual snow cover comparison using Sentinel-2 remote sensing data. Thereafter, interannual variability in day of snow disappearance, day of snow onset, duration of snow-free period, and maximum snow depth have been analysed and these trends are then discussed in detail.The results show that for the most non-glaciated regions in Svalbard, the snow onset is happening later in the winter season while the day of snow disappearance is arriving earlier in the spring. Consequently, the duration of snow-free period has increased in almost all regions of Svalbard except a few sites where the duration of the snow free-period has decreased most likely due to local climatic factors. These factors can be better understood by incorporating meteorological elements like precipitation, air temperature and wind speed. Overall, the CARRA reanalysis dataset is very good in determining snow cover trends in non- glaciated regions of Svalbard and with some updates and modifications, it might be able to determine snowcover for the glaciated regions in future.

No description available.

PURPOSE: To investigate the effect of the menstrual cycle (MC) on exercise performance across the power-duration relationship (PDR). We hypothesized females would exhibit greater variability in the PDR across the MC than males across a similar timespan, with critical power (PCRIT) and Work prime (W') being lower during the early follicular phase than the late follicular and mid-luteal phases. METHODS: Eumenorrheic, endurance-trained females (n = 10, age = 24.1 ± 5.59) performed multiple constant-load-to-task-failure and maximum-power tests at three time points across the MC (early follicular, late follicular, midluteal phases). Endurance-trained males (n = 10 age = 29.5 ± 9.18) performed the same tests approximately 10 days apart to mimic the time between the phases of the MC. RESULTS: No differences across the PDR were observed between MC phases (PCRIT: 175.66 ± 34.97 W, P = 0.632, CV = 1.28 ± 0.97 %) (W': 7916.53 ± 2316.69 J, P = 0.283, CV = 13.56 ± 6.93 %). PCRIT was similar for males and females (11.82 ± 1.44 W • kg-1 vs. 11.20 ± 1.82 W • kg?1, respectively) when controlling for leg lean mass. However, W' was larger (P = 0.048) for males (617.28 ± 130.10 J • kg?1) than females (505.24 ± 137.66 J • kg?1). CONCLUSION: These findings indicate that researchers do not need to account for MC phase when conducting performance research on female subjects. Nevertheless, factors, such as body size and leg lean body mass, do limit exercise performance in males and females. As such, previous studies looking at factors limiting exercise performance in males may not always apply to females.

Research has consistently shown group psychotherapy to be an effective form of treatment. Group cohesiveness, the quantity and magnitude of the strength of the bonds within the group, has received considerable attention. This study describes the integration of the cohesion literature using a random effects meta-analysis to ascertain the magnitude of the relationship between cohesion and outcome as well as explore the effect specific group variables have on this association. Studies were included which measured the relationship between groups comprised of at least three members, included both an outcome and cohesion measure convertible to an effect size, and were published in English. 40 published studies, comprised of 3,323 participants, were analyzed and yielded an omnibus effect size of r = .25, suggesting a positive, moderate relationship exists between cohesion and outcome. Four group variables (group size, treatment duration, treatment setting, and group focus) and a client variable (age) demonstrated markedly stronger relationships with cohesion. The study also examined the most frequently used cohesion measures and definitions as they relate to their relationship to outcome and frequency of use. Clinical implications for group therapists are identified and future research suggested.