985 resultados para 96-well microplate
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Background Achieving the goals set by Roll Back Malaria and the Government of Kenya for use of insecticide treated bednets (ITNs) will require that the private retail market for nets and insecticide treatments grow substantially. This paper applies some basic concepts of market structure and pricing to a set of recently-collected retail price data from Kenya in order to answer the question, “How well are Kenyan retail markets for ITNs working?” Methods Data on the availability and prices of ITNs at a wide range of retail outlets throughout Kenya were collected in January 2002, and vendors and manufacturers were interviewed regarding market structure. Findings Untreated nets are manufactured in Kenya by a number of companies and are widely available in large and medium-sized towns. Availability in smaller villages is limited. There is relatively little geographic price variation, and nets can be found at competitive prices in towns and cities. Marketing margins on prices appear to be within normal ranges. No finished nets are imported. Few pre-treated nets or net+treatment combinations are available, with the exception of the subsidized Supanet/Power Tab combination marketed by a donor-funded social marketing project. Conclusions Retail markets for untreated nets in Kenya are well established and appear to be competitive. Markets for treated nets and insecticide treatment kits are not well established. The role of subsidized ITN marketing projects should be monitored to ensure that these projects support, rather than hinder, the development of retail markets.
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The Transmission Control Protocol (TCP) has been the protocol of choice for many Internet applications requiring reliable connections. The design of TCP has been challenged by the extension of connections over wireless links. We ask a fundamental question: What is the basic predictive power of TCP of network state, including wireless error conditions? The goal is to improve or readily exploit this predictive power to enable TCP (or variants) to perform well in generalized network settings. To that end, we use Maximum Likelihood Ratio tests to evaluate TCP as a detector/estimator. We quantify how well network state can be estimated, given network response such as distributions of packet delays or TCP throughput that are conditioned on the type of packet loss. Using our model-based approach and extensive simulations, we demonstrate that congestion-induced losses and losses due to wireless transmission errors produce sufficiently different statistics upon which an efficient detector can be built; distributions of network loads can provide effective means for estimating packet loss type; and packet delay is a better signal of network state than short-term throughput. We demonstrate how estimation accuracy is influenced by different proportions of congestion versus wireless losses and penalties on incorrect estimation.
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This report summarizes the technical presentations and discussions that took place during RTDB'96: the First International Workshop on Real-Time Databases, which was held on March 7 and 8, 1996 in Newport Beach, California. The main goals of this project were to (1) review recent advances in real-time database systems research, (2) to promote interaction among real-time database researchers and practitioners, and (3) to evaluate the maturity and directions of real-time database technology.
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Purpose – To consider the economic and physical impact of electronic journals on remotely stored print stock. Design/methodology/approach – A collection of print journals was used as an object for consideration. Physical and heritage aspects of the collection are examined and questions are posed regarding the wisdom of future retention in response to increased demand for electronic alternatives. Findings – Emerging trends predict a predominance of periodical literature in electronic form. The future of local remote storage for low demand printed journal collections needs to be evaluated in economic as well as cultural terms. Research limitations/implications – Based on a collection at the Boole Library, University College Cork, Ireland. Practical implications – Similar consideration should be given to collections in other regional libraries. Originality/value – Contributes to discussions on the long-term value of retaining print journal holdings.
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The multiquantum barrier (MQB), proposed by Iga et al in 1986, has been shown by several researchers to be an effective structure for improving the operating characteristics of laser diodes. These improvements include a reduction in the laser threshold current and increased characteristic temperatures. The operation of the MQB has been described as providing an increased barrier to electron overflow by reflecting high energy electrons trying to escape from the active region of the laser.This is achieved in a manner analogous to a Bragg reflector in optics. This thesis presents an investigation of the effectiveness of the MQB as an electron reflector. Numerical models have been developed for calculating the electron reflection due to MQB. Novel optical and electrical characterisation techniques have been used to try to measure an increase in barrier height due to the MQB in AlGaInP.It has been shown that the inclusion of MQB structures in bulk double heterostructure visible laser diodes can halve the threshold current above room temperature and the characteristic temperature of these lasers can be increased by up to 20K.These improvements are shown to occur in visible laser diodes even with the inclusion of theoretically ineffective MQB structures, hence the observed improvement in the characteristics of the laser diodes described above cannot be uniquely attributed to an increased barrier height due to enhance electron reflection. It is proposed here that the MQB improves the performance of laser diodes by proventing the diffusion of zinc into the active region of the laser. It is also proposed that the trapped zinc in the MQB region of the laser diode locally increases the p-type doping bringing the quasi-Fermi level for holes closer to the valence band edge thus increasing the barrier to electron overflow in the conduction band.
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Leachate may be defined as any liquid percolating through deposited waste and emitted from or contained within a landfill. If leachate migrates from a site it may pose a severe threat to the surrounding environment. Increasingly stringent environmental legislation both at European level and national level (Republic of Ireland) regarding the operation of landfill sites, control of associated emissions, as well as requirements for restoration and aftercare management (up to 30 years) has prompted research for this project into the design and development of a low cost, low maintenance, low technology trial system to treat landfill leachate at Kinsale Road Landfill Site, located on the outskirts of Cork city. A trial leachate treatment plant was constructed consisting of 14 separate treatment units (10 open top cylindrical cells [Ø 1.8 m x 2.0 high] and four reed beds [5.0m x 5.0m x 1.0m]) incorporating various alternative natural treatment processes including reed beds (vertical flow [VF] and horizontal flow [HF]), grass treatment planes, compost units, timber chip units, compost-timber chip units, stratified sand filters and willow treatment plots. High treatment efficiencies were achieved in units operating in sequence containing compost and timber chip media, vertical flow reed beds and grass treatment planes. Pollutant load removal rates of 99% for NH4, 84% for BOD5, 46% for COD, 63% for suspended solids, 94% for iron and 98% for manganese were recorded in the final effluent of successfully operated sequences at irrigation rates of 945 l/m2/day in the cylindrical cells and 96 l/m2/day in the VF reed beds and grass treatment planes. Almost total pathogen removal (E. coli) occurred in the final effluent of the same sequence. Denitrification rates of 37% were achieved for a limited period. A draft, up-scaled leachate treatment plant is presented, based on treatment performance of the trial plant.
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The present research examines the issue of universal interventions designed to enhance wellbeing among a community-based adolescent population. The first phase saw a cross-sectional survey conducted among Transition Year students in 13 secondary schools in Cork city and county, Republic of Ireland, with a view towards identifying dimensions linked with wellbeing (operationalised as subjective happiness, life satisfaction, and depressive symptoms) and which might prove effective in informing intervention approaches. Arising from this, mindfulness, gratitude, and cognitive-behavioural dimensions emerged as predictors of wellbeing, and short interventions (four sessions/four weeks) informed by each were conducted with participant groups in three secondary schools, one intervention in each school. Results from statistical analysis showed that the mindfulness and cognitive-behavioural interventions facilitated significant reductions in depressive symptoms among active condition participants at post-test, but that these benefits were not sustained over time, while no statistically significant changes were detected on subjective happiness and life satisfaction. The gratitude intervention was found to have had no effect on the three outcome variables. The findings are discussed in the context of theory and past research, while limitations, implications, and possible future directions are also addressed.
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This thesis explores the psychosocial wellbeing of sub-Saharan African migrant children in Ireland. A sociocultural ecological (Psychosocial Working Group, 2003) and resilience lens (Masten & Obradovic, 2008; Ungar, 2011) is used to analyse the experiences of African migrant children in Ireland. The research strategy employs a mixed-methods design, combining both an etic and emic perspective. Grounded theory inquiry (Strauss and Corbin, 1994) explores the experiences of African migrant children in Ireland by drawing on multi-sited observations over a period of six months in 2009, and on interviews and focus group discussions conducted with African children (aged 13-18), mothers and fathers. An emically derived ‘African Migrant Child Psychosocial Well-being’ scale was developed by drawing on data gathered through rapid ethnographic (RAE) free listing exercises carried out in Cork, Dublin and Dundalk with sixty-one participants (N=21 adults, N=28 15-18-year-olds, N=12 12-14-year-olds) and three African community key informants to elicit local understandings of psychosocial well-being. This newly developed scale was used alongside standardised measures of well-being to quantitatively measure the psychosocial adjustment of 233 African migrant children in Cork, Dublin and Dundalk aged 11-18. Findings indicate that the psychosocial wellbeing of the study population is satisfactory when benchmarked against the psychosocial health profile of Irish youth (Dooley & Fitzgerald, 2012). These findings are similar to trends reported in international literature in this field (Georgiades et al., 2006; Gonneke, Stevens, Vollebergh, 2008; Sampson et al., 2005). Study findings have implications for advancing psychosocial research methods with non-Western populations and on informing the practice of Irish professionals, mainly in the areas of teaching, psychology and community work.
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Prenatal well-being can have significant effects on the mother and developing foetus. Positive psychological interventions, including gratitude and mindfulness, consistently demonstrate benefits for well-being in diverse populations. No research has been conducted on gratitude during pregnancy; the few studies of prenatal mindfulness interventions have demonstrated well-being benefits. The current study examined the effects of gratitude and mindfulness interventions on prenatal maternal well-being, cortisol and birth outcomes. Five studies were conducted. Study 1 was a systematic review of mindfulness intervention effects on cortisol; this highlighted potential benefits of mindfulness but the need for rigorous protocols in future research. In Study 2 a gratitude and a mindfulness intervention were developed and evaluated; findings indicate usefulness of two 3 week interventions. Study 3 examined the effects of these interventions in a randomised controlled trial (RCT) of non-pregnant women, before examining a pregnant group. No significant intervention effects were found in this study, potentially due to insufficient power and poor protocol adherence. Changes in expected directions were observed for most outcomes and the potential utility of a combined gratitude and mindfulness intervention was noted. In Study 4 a gratitude during pregnancy (GDP) scale was developed and the reliability of an existing mindfulness measure (MAAS) was examined in a pregnant group. Both scales were found to be suitable and reliable measures in pregnancy. Study 5 incorporated the findings of the previous four studies to examine of the effect of a combined mindfulness and gratitude intervention with a group of pregnant women. Forty-six participants took part in a 5-week RCT that examined intervention effects on prenatal gratitude, mindfulness, happiness, satisfaction with life, social support, prenatal stress, depression and sleep. Findings indicated that the intervention improved sleep quality and that effects for prenatal distress were approaching significance. Issues of attrition and non-compliance to study protocols were problematic and are discussed. In summary, the current thesis highlights the need for robust measurement, and intervention and cortisol sampling protocols in future research, particularly with pregnant groups. Findings also demonstrate tentative benefits of a gratitude and mindfulness intervention during pregnancy.
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PURPOSE: Overall survival (OS) can be observed only after prolonged follow-up, and any potential effect of first-line therapies on OS may be confounded by the effects of subsequent therapy. We investigated whether tumor response, disease control, progression-free survival (PFS), or time to progression (TTP) could be considered a valid surrogate for OS to assess the benefits of first-line therapies for patients with metastatic breast cancer. PATIENTS AND METHODS: Individual patient data were collected on 3,953 patients in 11 randomized trials that compared an anthracycline (alone or in combination) with a taxane (alone or in combination with an anthracycline). Surrogacy was assessed through the correlation between the end points as well as through the correlation between the treatment effects on the end points. RESULTS: Tumor response (survival odds ratio [OR], 6.2; 95% CI, 5.3 to 7.0) and disease control (survival OR, 5.5; 95% CI, 4.8 to 6.3) were strongly associated with OS. PFS (rank correlation coefficient, 0.688; 95% CI, 0.686 to 0.690) and TTP (rank correlation coefficient, 0.682; 95% CI, 0.680 to 0.684) were moderately associated with OS. Response log ORs were strongly correlated with PFS log hazard ratios (linear coefficient [rho], 0.96; 95% CI, 0.73 to 1.19). Response and disease control log ORs and PFS and TTP log hazard ratios were poorly correlated with log hazard ratios for OS, but the confidence limits of rho were too wide to be informative. CONCLUSION: No end point could be demonstrated as a good surrogate for OS in these trials. Tumor response may be an acceptable surrogate for PFS.
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OBJECTIVE: This study examines the degree to which a married individual's health habits and use of preventive medical care are influenced by his or her spouse's behaviors. STUDY DESIGN: Using longitudinal data on individuals and their spouses, we examine changes over time in the health habits of each person as a function of changes in his or her spouse's health habits. Specifically, we analyze changes in smoking, drinking, exercising, cholesterol screening, and obtaining a flu shot. DATA SOURCE: This study uses data from the Health and Retirement Study (HRS), a nationally representative sample of individuals born between 1931 and 1941 and their spouses. Beginning in 1992, 12,652 persons (age-eligible individuals as well as their spouses) from 7,702 households were surveyed about many aspects of their life, including health behaviors, use of preventive services, and disease diagnosis. SAMPLE: The analytic sample includes 6,072 individuals who are married at the time of the initial HRS survey and who remain married and in the sample at the time of the 1996 and 2000 waves. PRINCIPAL FINDINGS: We consistently find that when one spouse improves his or her behavior, the other spouse is likely to do so as well. This is found across all the behaviors analyzed, and persists despite controlling for many other factors. CONCLUSIONS: Simultaneous changes occur in a number of health behaviors. This conclusion has prescriptive implications for developing interventions, treatments, and policies to improve health habits and for evaluating the impact of such measures.
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Directional drilling and hydraulic-fracturing technologies are dramatically increasing natural-gas extraction. In aquifers overlying the Marcellus and Utica shale formations of northeastern Pennsylvania and upstate New York, we document systematic evidence for methane contamination of drinking water associated with shale-gas extraction. In active gas-extraction areas (one or more gas wells within 1 km), average and maximum methane concentrations in drinking-water wells increased with proximity to the nearest gas well and were 19.2 and 64 mg CH(4) L(-1) (n = 26), a potential explosion hazard; in contrast, dissolved methane samples in neighboring nonextraction sites (no gas wells within 1 km) within similar geologic formations and hydrogeologic regimes averaged only 1.1 mg L(-1) (P < 0.05; n = 34). Average δ(13)C-CH(4) values of dissolved methane in shallow groundwater were significantly less negative for active than for nonactive sites (-37 ± 7‰ and -54 ± 11‰, respectively; P < 0.0001). These δ(13)C-CH(4) data, coupled with the ratios of methane-to-higher-chain hydrocarbons, and δ(2)H-CH(4) values, are consistent with deeper thermogenic methane sources such as the Marcellus and Utica shales at the active sites and matched gas geochemistry from gas wells nearby. In contrast, lower-concentration samples from shallow groundwater at nonactive sites had isotopic signatures reflecting a more biogenic or mixed biogenic/thermogenic methane source. We found no evidence for contamination of drinking-water samples with deep saline brines or fracturing fluids. We conclude that greater stewardship, data, and-possibly-regulation are needed to ensure the sustainable future of shale-gas extraction and to improve public confidence in its use.
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All This the World Well Knows is a 30-minute symphonic cantata for mixed chorus, four solo voices (soprano, mezzo-soprano, tenor, and baritone), and orchestra. The libretto, adapted by the composer, weaves together texts from Shakespeare's Dark Lady sonnets and from the King James Bible's book of Proverbs in a loose narrative of love, betrayal, and reconciliation. The composition's pitch material includes microtonality that arises from the just intonation of sonorities derived from the harmonic series. In passages in which the solo voices express this microtonality, they are amplified in order to allow precise, non vibrato intonation. The modest size of the orchestra, which includes pairs of winds and only two percussionists, makes the composition practical for a wide range of performing groups.
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As a psychological principle, the golden rule represents an ethic of universal empathic concern. It is, surprisingly, present in the sacred texts of virtually all religions, and in philosophical works across eras and continents. Building on the literature demonstrating a positive impact of prosocial behavior on well-being, the present study investigates the psychological function of universal empathic concern in Indian Hindus, Christians, Muslims and Sikhs.
I develop a measure of the centrality of the golden rule-based ethic, within an individual’s understanding of his or her religion, that is applicable to all theistic religions. I then explore the consistency of its relationships with psychological well-being and other variables across religious groups.
Results indicate that this construct, named Moral Concern Religious Focus, can be reliably measured in disparate religious groups, and consistently predicts well-being across them. With measures of Intrinsic, Extrinsic and Quest religious orientations in the model, only Moral Concern and religiosity predict well-being. Moral Concern alone mediates the relationship between religiosity and well-being, and explains more variance in well-being than religiosity alone. The relationship between Moral Concern and well-being is mediated by increased preference for prosocial values, more satisfying interpersonal relationships, and greater meaning in life. In addition, across religious groups Moral Concern is associated with better self-reported physical and mental health, and more compassionate attitudes toward oneself and others.
Two additional types of religious focus are identified: Personal Gain, representing the motive to use religion to improve one’s life, and Relationship with God. Personal Gain is found to predict reduced preference for prosocial values, less meaning in life, and lower quality of relationships. It is associated with greater interference of pain and physical or mental health problems with daily activities, and lower self-compassion. Relationship with God is found to be associated primarily with religious variables and greater meaning in life.
I conclude that individual differences in the centrality of the golden rule and its associated ethic of universal empathic concern may play an important role in explaining the variability in associations between religion, prosocial behavior and well-being noted in the literature.
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Whether a terminally ill cancer patient should be actively fed or simply hydrated through subcutaneous or intravenous infusion of isotonic fluids is a matter of ongoing controversy among clinicians involved in the care of these patients. Under the auspices of the European Association for Palliative Care, a committee of experts developed guidelines to help clinicians make a reasonable decision on what type of nutritional support should be provided on a case-by-case basis. It was acknowledged that part of the controversy related to the definition of the terminal cancer patient, since this is a heterogeneous group of patients with different needs, expectations, and potential for a medical intervention. A major difficulty is the prediction of life expectancy and the patient's likely response to vigorous nutritional support. In an attempt to reach a decision on the type of treatment support (artificial nutrition vs. hydration) which would best meet the needs and expectations of the patient, we propose a three-step process: Step I: define the eight key elements necessary to reach a decision: Step II: make the decision; and Step III: reevaluate the patient and the proposed treatment at specified intervals. Step I involves assessing the patient concerning the following: 1) oncological/clinical condition; 2) symptoms; 3) expected length of survival; 4) hydration and nutritional status; 5) spontaneous or voluntary nutrient intake; 6) psychological profile; 7) gut function and potential route of administration; and 8) need for special services based on type of nutritional support prescribed. Step II involves the overall assessment of pros and cons, based on information determined in Step I, in order to reach an appropriate decision based on a well-defined end point (i.e. improvement of quality of life; maintaining patient survival; attaining rehydration). Step III involves the periodic reevaluation of the decision made in Step II based on the proposed goal and the attained result.