Laser-induced transient absorption spectroscopy of phthalocyanine dyes

This work reports a further investigation into the spectroscopic properties of phthalocyanine dyes in solution. The technique of nanosecond kinetic spectrophotometry was applied, with excitation at both the fundamental ruby laser output wavelength (694 nm) and the second harmonic (347 nm); corresponding in energy to the first and second excited singlet states respectively of several of the phthalocyanine compounds. The resultant transient absorption spectra indicate that the same laser—induced intermediates — those that can be identified as the lowest excited states of singlet and triplet multiplicity — are produced following excitation at either wavelength. However, the transient response also displays a marked perturbation from that characteristic of a 'simple' energy redistribution process; a perturbation that is deduced to be a consequence of both the high intensity of laser excitation and the tendency of the phthalocyanine dyes to form molecular aggregates. Further evidence is proposed regarding the 'anomalous blue fluorescence' reported from this type of compound, with particular emphasis placed upon the need for a high degree of solute purity

The axial behaviour of piled foundations in liquefiable soil

Understanding the mechanisms by which any engineering structure resists load is an essential requirement for its consistent and reliable design. The axial resistance which can be mobilised by piled foundations in liquefiable soils when subjected to strong shaking remains highly uncertain, and a number of piled foundations have failed in strong earthquakes as recently as 2011 . The lack of visible foundation distress in many such cases indicates that failure can occur as a result of the loss of axial capacity during an earthquake, as opposed to the laterally-dominated failure modes which have been the focus of the research community for the last 20 to 30 years. In this thesis, a series of dynamic centrifuge experiments have been carried out to establish how the distribution of axial loads along the length of a pile changes during a strong earthquake. In each test, a 2 × 2 pile group was installed such that its tips were embedded in a dense sand layer which was overlain by liquefiable soil. The tests examine the effects arising from the hydraulic conductivity in the bearing layer, the influence of axial pile cap support and finally whether there are any differences in the behaviour of nominally jacked or bored piles under seismic loading. The pile cap has been shown to play a substantial role in supporting axial loads during strong shaking. In cases where the pile cap was unable to support axial load, the majority of the axial loading was carried as pile end bearing, with some shaft friction being mobilised in both the liquefiable and bearing soil layers as a result of relative lateral displacements between the soil and pile. However, where the pile cap is able to support axial loads, the settlement of the pile cap into the soil led to a dramatic transfer of axial load away from the piles and onto the pile cap. These results imply that where substantial excess pore pressures may be generated at the depth of the pile tip, then the pile caps must be able to support significant axial load. The increased effective stresses below the pile cap were responsible for the mobilisation of shaft friction on the section of pile within the liquefiable layer. However, these piles were unable to mobilise shaft friction in the bearing layer due to the reduced lateral loading on the piles. The axial behaviour of the piled foundations after the end of strong shaking is affected by the recovery of pile end bearing capacity and is therefore strongly dependent on the hydraulic conductivity of the bearing layer. The axial behaviour of nominally bored and jacked pile groups in liquefiable soil deposits are very different under seismic excitation, with the installation process of the latter substantially altering the soil conditions around the tips of the pile, such that in contrast to the bored pile groups, the jacked pile groups did not accumulate settlements until significantly after the strong shaking had commenced. These results imply that the method of installation is an important factor in the seismic response of a foundation, and may be more pronounced for real earthquakes where the number of strong shaking cycles may be more limited than those simulated in the experiments.This work was supported by the Engineering and Physical Sciences Research Counci

Planning for Sustainability in Small Municipalities: The Influence of Interest Groups, Growth Patterns, and Institutional Characteristics

How and why small municipalities promote sustainability through planning efforts is poorly understood. We analyzed ordinances in 451 Maine municipalities and tested theories of policy adoption using regression analysis.We found that smaller communities do adopt programs that contribute to sustainability relevant to their scale and context. In line with the political market theory, we found that municipalities with strong environmental interests, higher growth, and more formal governments were more likely to adopt these policies. Consideration of context and capacity in planning for sustainability will help planners better identify and benefit from collaboration, training, and outreach opportunities

A survey and recommendations for asthma education

This project addresses the public health problem of asthma from a social ecological perspective. This analysis of asthma emphasizes the important elements of transactions between individuals, communities, and institutions that determine the nature of health needs, resources and constraints in environmental settings (Stokols, 1992). The purpose of this study was to initiate the process of acquiring a better understanding of the problem of adult asthma as it exists in Santa Barbara, California. According to officials representing the California Statistical Data Center and local public health agencies, asthma is not considered a reportable disease because it is not a communicable infectious condition. As a result, health service organizations have not been mandated to comprehensively evaluate the problem of asthma, particularly among adult populations. A more aggressive approach would include collecting data about the rate of hospital admissions and treatment, results of treatment, and the level of follow-up patient education. There appears to be very little comprehensive information about the demographic and epidemiological dimensions of adult asthma, or the effectiveness of adult asthma education in local communities. Therefore, this project involved the administration of a needs assessment survey to evaluate the educational needs of adult asthma patients living in Santa Barbara, California. A specialty-care clinic under the direction of a physician specializing in the treatment of asthma was used as the site for the implementation of this study. Twenty adult asthma patients completed an anonymous survey during their visits to the clinic. Analysis of the survey revealed a need for asthma management education related to mitigating environmental "triggers". The survey results also reflected the need for education regarding emotional and behavioral aspects of adult asthma. Relatively high interest was expressed by the respondents to learn more about maintaining and/or improving their condition with exercise, nutrition, and massage. Analysis of the results also indicated an interest in better understanding asthma medications. Because the survey was completed by a very small group, recommendations are directed only toward the adult population receiving treatment in the clinic where the needs assessment was administered. Based on the data which emerged from the literature combined with the findings of the survey, suggestions for health education activities are directed toward the group of individuals who completed the survey. Additionally, recommendations for administering a future needs assessment among a larger population are offered.California State University, Northridge. Department of Health Sciences.Includes bibliographical references (leaves 50-55

Effect of Partial Saturation on Liquefaction Triggering

To correlate liquefaction resistance with degree of saturation for characteristics Christchurch soils including sands with fines and silts. To incorporate the effects of saturation in simplified procedures for liquefaction assessment. Provide basis for quantifying the effects of partial saturation in advanced seismic analysis

Comparing adaptive management and transition management

For addressing and governing long-term socialecological change two different framworks are available: transition management and adaptive management. They emphasise the roles of social learning and stakeholder participation in different contexts

Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia