Variability In Population Trends, Life History Characteristics, Amd Milk Composition Of Northern Fur Seals In Alaska

Thesis (M.S.) University of Alaska Fairbanks, 2012The northern fur seal population on the Pribilof Islands has been declining since the 1960s and is now less than 30% of its former size. Chapter 1 examines factors that might cause a population to decrease to such an extent and concludes that only nutritional limitation caused by climate change or commercial fisheries, predation by killer whales, or a combination of factors that includes conditions in the North Pacific during the winter were possible explanations. Chapter 2 reports the seasonal patterns in proximate composition of fur seal milk between St. Paul Island (one of the Pribilof Islands) and Bogoslof Island (an increasing population) to understand the energy requirements of lactation and the energetics of pup growth and body condition at weaning. Factors that caused variability in milk composition included days postpartum, time ashore, individual phenotype, island and preceding trip duration. Average milk lipid increased from 45.5+/-0.7% to 53.8+/-1.0% at St. Paul and from 45.8+/-0.7% to 57.3+/-0.8% at Bogoslof between July and October, while average milk protein remained relatively stable ranging between 10.0% and 10.5%. The lipid content of northern fur seal milk near peak lactation is the highest reported among otariid seals and among the highest known for all mammals

The Impact of Altered Timing of Eating, Sleep and Work Patterns on Human Health

Some 20% of the population is required to work outside the regular 9:00 a.m.–5:00 p.m. working day, and this number is likely to increase as economic demands push work hours into the night for many companies. These irregular schedules mean workers often have to sleep during the day and be awake at night. This causes a misalignment between normal day-light entrained internal physiological processes, such as metabolism and digestion, and the external environment. As a direct consequence, night workers have poorer health than day workers, even after controlling for lifestyle and socioeconomic status. The purpose of this Special Issue is to highlight the interrelationships between timing of food intake and diet quality with sleep and work patterns in humans with an emphasis on randomized controlled trials or meta-analyses of data from published studies

Developmental risk among Aboriginal children living in urban areas in Australia : the Study of Environment on Aboriginal Resilience and Child Health (SEARCH)

Background: Most Australian Aboriginal children are on track with their development, however, the prevalence of children at risk of or with a developmental or behavioural problem is higher than in other children. Aboriginal child development data mostly comes from remote communities, whereas most Aboriginal children live in urban settings. We quantified the proportion of participating children at moderate and high developmental risk as identified by caregivers' concerns, and determined the factors associated with developmental risk among urban Aboriginal communities. Methods: Study methods were co-designed and implemented with four participating urban Aboriginal Community Controlled Health Services in New South Wales, Australia, between 2008 and 2012. Caregiver-reported data on children < 8 years old enrolled in a longitudinal cohort study (Study of Environment on Aboriginal Resilience and Child Health: SEARCH) were collected by interview. The Parents' Evaluation of Developmental Status (PEDS) was used to assess developmental risk through report of caregiver concerns. Odds ratios (OR) were calculated using multinomial logistic regression to investigate risk factors and develop a risk prediction model. Results: Of 725 children in SEARCH with PEDS data (69% of eligible), 405 (56%) were male, and 336 (46%) were aged between 4.5 and 8 years. Using PEDS, 32% were at high, 28% moderate, and 40% low/no developmental risk. Compared with low/no risk, factors associated with high developmental risk in a mutually-adjusted model, with additional adjustment for study site, were male sex (OR 2.42, 95% confidence intervals 1.62-3.61), being older (4.5 to < 8 years versus < 3 years old, 3.80, 2.21-6.54), prior history of ear infection (1.95, 1.21-3.15), having lived in 4 or more houses versus one house (4.13, 2.04-8.35), foster care versus living with a parent (5.45, 2.32-12.78), and having a caregiver with psychological distress (2.40, 1.37-4.20). Conclusion: In SEARCH, 40% of urban Aboriginal children younger than 8 years were at no or low developmental risk. Several factors associated with higher developmental risk were modifiable. Aboriginal community-driven programs to improve detection of developmental problems and facilitate early intervention are needed

Influence of chemistry and runout table parameters on hot coil collapse in C-Mn steels

The key metallurgical parameters affecting the incidence of coil collapse (soft slump) of C-Mn steels has been investigated using industrial data and laboratory simulation. Runout table (ROT) cooling/coiling simulations were performed on a Gleeble 1500D to study transformation before and during coiling of thin strip. For low C (< 0.07%) grades, coiling temperatures above 650˚C coupled with high nitrogen contents decreased the transformation-end temperature, Ar1, and increased collapse. Coiling temperatures above the Ar1 for ROT cooling increased both dilation and the time to complete transformation during coiling. These effects correlated with industrial conditions where a high frequency of coil collapse was observed

Social and emotional developmental vulnerability at age five in Aboriginal and non-Aboriginal children in New South Wales: a population data linkage study

Background Early childhood social and emotional development underpins later social, emotional, academic and other outcomes. The first aim of this study was to explore the association between child, family and area-level characteristics associated with developmental vulnerability, amongst Aboriginal and non-Aboriginal children in their first year of school. The second aim was to quantify the magnitude of the social and emotional developmental inequalities between Aboriginal and non-Aboriginal children and the extent to which differences in socioeconomic disadvantage and perinatal characteristics explained this inequality. Methods This retrospective cohort study used cross-sectoral data linkage to identify and follow participants from birth to school age. In this way, social and emotional development was examined in 7,384 Aboriginal and 95,104 non-Aboriginal children who were included in the Australian Early Development Census in their first year of full-time school in New South Wales (NSW) in 2009 or 2012 and had a birth registration and/or perinatal record in NSW. The primary outcome measures were teacher-reported social competence and emotional maturity as measured using the Australian version of the Early Development Instrument. Results The mean age at the start of the school year for children in the study sample was 5.2 years (SD = 0.36 years). While 84% of Aboriginal children scored favourably - above the vulnerability threshold – for social competence and 88% for emotional maturity, Aboriginal children were twice as likely as non-Aboriginal children to be vulnerable on measures of social development (RR = 2.00; 95%CI, 1.89–2.12) and had 89% more risk of emotional vulnerability (RR = 1.89; 95%CI, 1.77–2.02). The inequality between Aboriginal and non-Aboriginal children was largely explained by differences in the socioeconomic and perinatal health characteristics of children and families. Thus, after adjusting for differences in measures of socioeconomic advantage and disadvantage (Model 2), the relative risk was attenuated to 1.31 (95% CI: 1.23–1.40) on the social competence domain and 1.24 (95% CI, 1.15–1.33) on the emotional maturity domain. Child, family and area-level characteristics associated with vulnerability were identified. Conclusions Most of the gap in early childhood social and emotional development between Aboriginal and non-Aboriginal children can be attributed to socioeconomic and early life health disadvantage. Culturally safe health and social policies addressing the socioeconomic and health inequalities experienced by Aboriginal children are urgently required.This work was supported by National Health and Medical Research Council of Australia (NHMRC) Project Grant (#1061713) and a Financial Markets Foundation for Children (Australia) grant (2016–341). AW was supported by a NSW Health Early-Mid Career Fellowship. KF was supported by an NHMRC Early Career Fellowship (#1016475) and an NHMRC capacity building grant (#573122). EB was supported by an NHMRC Principal Research Fellowship (#1136128). SE was supported by an NHMRC Career Development Fellowship (#1013418)

Influence of Ti on the hot ductility of Nb containing steels

The influence of a low Ti addition, (~0.01%) on the hot ductility of Nb containing steels has been examined. For conventional cooling conditions in which an average cooling rate from the melting point to the test temperature was used, the ductility decreased markedly with the addition of Ti. However, when cooling conditions after melting were more in accord with the thermal heat treatment undergone by the strand during continuous casting, i.e. cooling is fast to begin with, reaches a minimum and then reheats, after which the temperature falls more slowly to the test temperature, the Ti addition was found to be beneficial