Sea ice off the coasts of Iceland in the early 20th Century

This thesis compares different sources of information about sea ice off the coasts of Iceland and presents new indices of sea ice severity for the years 1901-1925. The sea around Iceland is divided into eighteen Zones, each of which is given an icecode, referring to the amount of sea ice that was observed in each month. This information is tabulated and the reliability of the data sources is indicated. Further work with this data includes a description of the frequency of ice in each zone, year and month. The indices are compared with mean annual temperature in Stykkisholmur, W-Iceland, and with temperature anomalies for the whole Northern Hemisphere. The effects which the sea ice had in Iceland in this period are discussed.Digitisation of this thesis was sponsored by Arcadia Fund, a charitable fund of Lisbet Rausing and Peter Baldwin

Effects of nutrient loading in Lutz spruce seedlings (Picea x lutzii Littl.) during nursery rotation and on subsequent growth in field

Lutz spruce (Picea x lutzii Littl.) seedlings were nutrient loaded using four fertilization regimes, receiving in total 0, 7.8, 22.2 and 31.4 g N/m2 over a period of eight weeks (6th august – 27th September) to investigate the effects on biomass allocation, frost hardiness, root growth capacity and nutrient status after the nursery rotation. The total biomass of loaded seedlings was similar to unloaded seedlings after the nursery culture, but the increase in N from the nutrient loading was 29%, 41% and 48% for loaded treatments 7.8 – 31.4 mg N, respectively. A delay in accumulation of frost hardiness during the autumn was not detected, and the root growth capacity was not affected by the nutrient loading when measured the following spring. To investigate if the internal N status of the seedlings affected growth, survival and N content after one growing season in field, the seedlings were planted at two field trials (sites A and B), with or without field fertilizer. The shoots of loaded treatments without fertilizer application in the field had on average 31% and 52% more dry mass than unloaded treatments without fertilizer at sites A and B, respectively, after one growing season in field. Field fertilization also increased total shoot mass on average by 35% and 52% at sites A and B, respectively. The loading treatments without field fertilization increased N content in current needles by 104% and 109% for sites A and B, respectively. Field fertilization also increased N content on average in loaded treatments by 33% and 33% at site A and B, respectively. Nitrogen retranslocation from old to new needles was detected. The results illustrate the significance of retranslocation of stored nutrients to support new growth early in the season when root growth and nutrient uptake are still low. Survival was not affected by the nutrient loading after the first growing season, but fertilizing significantly decreased the damage caused by Otiorhynchus larvae in heath land. It was concluded that loading might provide an additional input for faster plantation establishment during the first crucial growing season after planting

A Longitudinal Study Of The Negative Impact Of Falls On Health, Well-Being, And Survival Among Older Adults: An Examination Of Protective Psychosocial Mediators

Falls can have detrimental effects on older adults’ physical and psychological health, and survival rates. However, there appears to be a protective psychosocial mediator that may lessen the negative impact of experiencing a fall on health and well-being. The psychosocial factors examined as mediators of the falls - health and well-being relationship in this study were dispositional optimism and perceived control. Participants were 232 community-dwelling older adults, age 68 or older. This study was linked to a longitudinal study including data collected in 2008 and 2010 (Grand Cities Healthy Aging Study (GCHAS). Measurements of dispositional optimism, perceived control, self-rated physical health, health-care utilization, number of falls, symptoms of depression, perceived stress and physical activity were examined. Survival was also tracked. Older adults who suffered a fall had poorer health and well-being cross-sectionally and at the two-year follow-up than those who did not suffer a fall. Perceived control mediated the negative impact of falls on certain current and subsequent health and well-being variables up to two years later. Among older adults who experienced a fall, higher levels of perceived control predicted better cross-sectional and subsequent health and well-being. Falls also predicted less likelihood of survival seven years later, with covariates accounted for. These findings have clinical implications

The Role Of Individual Differences In Young Adults\u27 Responses To Graphic Health Harms Anti-Tobacco Media

Tobacco use is the most preventable cause of overall mortality. The highest smoking rate, about 30%, in the U.S. is among young adults between the ages of 18 and 25 years. Anti-tobacco media campaigns appear to be effective in preventing and reducing tobacco use, although little is known about how individual differences affect responses to anti-tobacco media. Participants were 144 students at the University of North Dakota. They watched six anti-tobacco advertisements that contained fear messages but varied in levels of graphic imagery. The following was measured: tobacco experience, self-control, locus of control, depression, stress, affect, arousal, valence, and effectiveness. Participants reported greater negative affect and greater effectiveness for the more graphic anti-tobacco advertisements. There appear to be some individual differences (gender, depression, locus of control, and smoking exposure) that predict responses to the ads. Overall, ads with more disgust-evoking graphic imagery were better anti-smoking ads than others