1,095 research outputs found
Alaska Coastal Community Youth and the Future
The Alaska Sea Grant College Program.
Project No. R/72-02.Executive Summary / Introduction / Background to the Research / Methods / Findings / Discussion and Policy Recommendations / Products from the Research / References Cited / Appendix A. Focus Group Protocol (High School) / Appendix B. Focus Group Protocol (12-20 year olds) / Appendix C. Focus Group Questionnaire / Appendix D. Occupational Rating Worksheet / Appendix E. Consent/Assent For
Worker Experiences of Accessibility in Post-Katrina New Orleans
Existing research has identified transportation challenges that low-income workers face, including a spatial mismatch between suburban entry level-jobs and urban low-income workers. These studies rely on travel models and secondary data and thus may not capture the temporal or other constraints that low-income workers experience. To better understand mobility patterns and accessibility as experienced, this analysis considers commute choices and perceptions of accessibility. Findings are based on open-ended surveys with 50 low-income workers in New Orleans and its inner suburbs. According to a sizable share of respondents (40%), transportation problems do not preclude applying to jobs. Black and centrally located respondents most commonly did not perceive transportation as a limitation to job opportunities. On the other hand, many respondents did describe an inability to get to suburban job opportunities. Even when missed job opportunities were not reported, almost all respondents cited transportation problems for some locations or activities, especially shopping. Losing a functional automobile was a common reason to change commute mode after Hurricane Katrina, indicating that low-income workers may shift in and out of car ownership, as well change home and job locations. A few respondents â mostly active mode usersâwere highly satisfied with their journey to work. Interviewees most commonly desired increased frequency and reliability as critical transit improvements. The mixed findings on perceived job accessibility demonstrate the need to better integrate transportation and workforce research and policy. In addition, more transportation research work on perceptions and actual challenges is needed, including the role of time in workplace demands and physical accessibility. Finally, given dynamic auto ownership status, jobs, and residential patterns, longitudinal study is needed
Project 1: Studies on the role of CLEC-2 and Syk in lymphatic development and response to radiation & Project 2: A role for atrial natiuretic peptide in platelet inhibition and evidence for compartmentation of cGMP signalling.
Project 1: The platelet C type lectin-like type II (CLEC-2) transmembrane receptor has been shown to interact with its endogenous ligand, podoplanin, on lymphatic endothelium and mediate separation from blood vessels. Here, conditional deletion of CLEC-2 or a mutation in signalling molecule Syk, specifically in the megakaryocyte/platelet lineage, was seen to cause a severe blood-lymphatic mixing phenotype. As constitutive loss of CLEC-2 in mice is lethal at birth, radiation chimeras have been pivotal to investigating the role of CLEC-2 in platelet function. This pilot study was conducted to investigate the role of platelets in the recovery from radiation injury. Mice were subjected to irradiation and reconstituted with CLEC-2+/+ or CLEC-2-/- foetal liver cells. Immunofluorescence in the intestinal mesentery at 9 days showed disrupted vasculature in CLEC-2-/- mice. The only visible difference between the two sets of chimeras was blood in the intestine of CLEC-2-/- mice at 28 days. Terminal deoxynucleotidyl end labeling (TUNEL) showed no difference in the percentage of apoptotic cells in the livers of CLEC-2+/+ and CLEC-2-/- mice but an increase in the spleen. These results support the idea of a progressive intestinal phenotype and support a role for CLEC-2 and Syk in the separation and organization of blood and lymphatic vessels.
Project 2: Nitric oxide (NO) has long been accepted as a potent and powerful inhibitor of platelet function acting through soluble guanylyl cyclase (sGC) to elevate levels of cyclic guanosine 3â,5â-monophosphate (cGMP). In cells such as cardiac myocytes, cGMP levels are also influenced by natriuretic peptides (NP) which bind to a particulate GC (pGC). Despite a number of studies indicating binding sites for atrial NP (ANP) on platelets, their influence on platelet function is unclear. Here it is demonstrated that NO and ANP mediate concentration-dependant inhibition of platelet aggregation to thrombin which is not overcome by high concentrations of the protease. ANP also stimulated weak phosphorylation of vasodilator stimulated phosphoprotein (VASP) in contrast to the robust response to NO and which was highly variable between donors. Further, sildenafil, a selective PDE5 inhibitor, was shown to enhance NO but not ANP mediated platelet inhibition and VASP phosphorylation indicating soluble and particulate cGMP pools are compartmentalised in platelets. Together these findings indicate a role for ANP in inhibiting platelet function which is distinct from that of NO
The roles of podoplanin and clec-2 in the development and maintenance of the cerebral vasculature
The C-type lectin-like receptor, CLEC-2, is constitutively expressed on platelets, with reported expression on a number of leukocyte subsets in adult mice. Constitutive or platelet-specific deletion of CLEC-2 in mice induces cerebral haemorrhaging by midgestation. In this thesis, I investigated the basis of this defect, hypothesising that it is mediated by the loss of CLEC-2 activation by its endogenous ligand, podoplanin, expressed on the developing neural tube. Podoplaninfl/fl mice were crossed to mice expressing PGK-Cre to induce deletion of podoplanin at the two-cell stage. Developing blood vessels were visualized by 3-dimensional microscopy and found to be aberrantly patterned in CLEC-2- and podoplanin-deficient mice, culminating in widespread cerebral haemorrhaging by mid-gestation. Haemorrhages were also observed following Nestin-Cre driven deletion of podoplanin on neural progenitors and following deletion of the platelet integrin, αIIbÎČ3. Together these studies support that neuro-epithelial-derived podoplanin interacts with platelet-CLEC-2 to guide the maturation and integrity of the cerebral vasculature and to prevent haemorrhage by stimulating platelet aggregation. Using tamoxifen-inducible deletion of CLEC-2 in adult mice, the expression profile of CLEC-2 was investigated and shown to be restricted to platelets and circulating B-lymphocytes and CD11bhigh Gr1high myeloid cells. Furthermore, loss of CLEC-2 in adult mice was shown to be dispensable for maintaining blood-brain barrier permeability
Academic Integrity as a Learning Opportunity for Our Students
Poster presented at 2016 E.C. Moore Symposiu
Psychosocial resources underlying disaster survivors' posttraumatic stress symptom trajectories: insight from in-depth interviews with mothers who survived Hurricane Katrina
Background: Weather-related disasters, including hurricanes, are becoming more frequent and severe due to climate change. Vulnerable populations, such as people with low income and racial and ethnic minorities, are particularly prone to increased levels of physical harm and psychiatric adversity from weather-related events.Objectives: We aimed to explore psychosocial resources and coping of survivors with three different posttraumatic stress symptom (PTSS) trajectories (High-Decreasing, Moderate-Decreasing, and High-Stable), after Hurricane Katrina across two different time points: F1 (1-year post-disaster) and F3 (12 years post-disaster).Method: Participants in this multi-method study were part of a larger cohort of the Resilience in Survivors of Katrina (RISK) project. Transcripts of interviews completed at the two time points were analysed using two qualitative methods, combining thematic analysis and narrative analysis, and providing both breadth of perspectives with the depth of specific case studies.Results: Sixteen survivors completed interviews at both F1 and F3. From our in-depth analysis of the data, we derived five inductive themes: 'Hope,' 'Adaptive vs maladaptive avoidance,' 'Emotional delay,' 'Acceptance, Finding Meaning and Being in the Moment,' and 'Coping strategies.' Survivors with High-Decreasing and Moderate-Decreasing PTSS trajectories experienced hope for future, accepted the hurricane and its results, and found efficient ways to cope with their situation. Survivors with High-Stable PTSS trajectories tended to express a lack of hope for future and struggled to be mindful and accept the hurricane and its harm. Unlike survivors with High-Decreasing and Moderate-Decreasing PTSS trajectories, survivors with High-Stable PTSS trajectories also reported less social and family support and faced more discrimination and racism.Conclusion: There are factors beyond individual-level psychosocial resources that may shape post-disaster resilience. When supporting survivors after a weather-related disaster, it is essential to provide ongoing psychological, financial, and physical assistance to bolster these resources
Vocal instability over time in individual male European nightjars, Caprimulgus europaeus : recommendations for acoustic monitoring and surveys
Acoustic monitoring of birds is developing rapidly as equipment, methods and analyses improve. However, most population monitoring studies still utilise traditional techniques like mark-recapture or line transects. Previous researchers used vocal recordings of male European nightjars, Caprimulgus europaeus, to identify individuals, finding that four acoustic parameters correctly assigned 98.5% of calls to individuals. We tested their methods on a population of European nightjars recorded over two successive breeding seasons and found that percentage of males correctly classified within a season reached a maximum of 73.5%, rising to 75% if full-length calls and 13 acoustic parameters were used. We tested whether males could be re-identified over a two-year period and found that only 20% of calls were assigned to the same putative territorial individuals, despite separate ringing data showing that males can maintain site fidelity for up to eight years. Our results indicate that the characteristics of male nightjar vocalisations may alter over time. We therefore recommend that vocal discrimination be used in conjunction with existing monitoring techniques when surveying for population monitoring, that as many call parameters as possible are used and that recording for automated presence/absence surveys takes place over a short time-frame
The effect of environmental degradation and land use change on malaria re-emergence in south Venezuela: a spatiotemporal modelling study
Background:
Malaria transmission is highly dependent on environmental conditions. The association between climatic variables and malaria transmission is well established, but the interaction between variations in climate and land use change, such as deforestation, is less well understood. Earth observation data provide a valuable and accessible resource to investigate these environmentâmalaria associations, in particular where little ground truth data are available. Progress towards malaria elimination in Latin America is being hindered by a surge of cases in Venezuela, a country that accounted for 53% of cases in the region in 2019. The country's economic and political crisis has fuelled economic migration to gold mining areas in the south, where extraction activities are expanding malaria vector habitats and sustaining disease transmission.
Methods:
In this spatiotemporal modelling study, we used multisource Earth observation data, including meteorological, land use change, and socioeconomic factors, and data on mining activity, to investigate how changes in the ecological landscape might have facilitated increases in the incidence of malaria in the past 20 years. We modelled spatiotemporal malaria case data for 1996â2016 using a Bayesian hierarchical mixed-model framework for BolĂvar state in Venezuela, a malaria foci where approximately 60% of national cases occur annually. We examined how mining activities were associated with malaria hotspots and also considered the potential effects of climate variation, seasonality, and spatial dependency structures.
Findings:
We found that malaria risk was increased in mining hotspots, which were important in sustaining transmission in BolĂvar state. We also found that the effect of temperature and rainfall variation differed depending on the level of deforestation in BolĂvar, where the increased risk of malaria with temperature was greatest in areas that were more deforested.
Interpretation:
Our findings provide important evidence of environmentally driven re-emergence of malaria and highlight the advantages of using Earth observation data for understanding malaria dynamics in areas with sparse or incomplete data records
Rangitoto volcano excursion, Auckland. Pre-conference field trip
Rangitoto is one of Auckland Cityâs more iconic landscape features. Guarding the entrance to the Waitemata Harbour, Rangitoto is a symmetrical, ~6-km wide, basaltic shield volcano that last erupted ~550 years ago shortly after the arrival and settlement of Polynesians in the Auckland region (c. 1280 AD). Rangitoto is by far the largest, and also the youngest, volcano in the Auckland Volcanic Field (AVF). The AVF is a monogenetic volcanic field consisting of approximately 53 individual eruptive centres, all of which are within the boundaries of the Auckland urban area. Recent research has revealed more about Rangitotoâs eruptive history, which may date back to c. 1500 years ago (Shane et al. 2013). Some of these findings have been noted below and will be discussed further while we ascend its summit and explore its various landscape and vegetational features
- âŠ