954 resultados para Illinois Agent Orange Study Commission.


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This study was designed to assess the potential of the continuous erythropoietin receptor activator (C.E.R.A.) to correct anemia at extended administration intervals in erythropoiesis-stimulating agent-naīve patients with chronic kidney disease (CKD) not on dialysis and to determine its optimal starting dose.

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With many real world decisions being made in conjunction with other decision makers, or single agent decisions having an influence on other members of the decision maker's immediate entourage, there is strong interest in studying the relative weight assigned to different agents in such contexts. In the present paper, we focus on the case of one member of a two person household being asked to make choices affecting the travel time and salary of both members. We highlight the presence of significant heterogeneity across individuals not just in their underlying sensitivities, but also in the relative weight they assign to their partner, and show how this weight varies across attributes. This is in contrast to existing work which uses weights assigned to individual agents at the level of the overall utility rather than for individual attributes. We also show clear evidence of a risk of confounding between heterogeneity in marginal sensitivities and heterogeneity in the weights assigned to each member. We show how this can lead to misleading model results, and argue that this may also explain past results showing bargaining or weight parameters outside the usual [0,1] range in more traditional joint decision making contexts. In terms of substantive results, we find that male respondents place more weight on their partner's travel time, while female respondents place more weight on their partner's salary.

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Background: Our previous laboratory and clinical data suggested that one mechanism underlying the development of platinum resistance in ovarian cancer is the acquisition of DNA methylation. We therefore tested the hypothesis that the DNA hypomethylating agent 5-aza-2'-deoxycytodine (decitabine) can reverse resistance to carboplatin in women with relapsed ovarian cancer.

Methods: Patients progressing 6-12 months after previous platinum therapy were randomised to decitabine on day 1 and carboplatin (AUC 6) on day 8, every 28 days or carboplatin alone. The primary objective was response rate in patients with methylated hMLH1 tumour DNA in plasma.

Results: After a pre-defined interim analysis, the study closed due to lack of efficacy and poor treatment deliverability in 15 patients treated with the combination. Responses by GCIG criteria were 9 out of 14 vs 3 out of 15 and by RECIST were 6 out of 13 vs 1 out of 12 for carboplatin and carboplatin/decitabine, respectively. Grade 3/4 neutropenia was more common with the combination (60% vs 15.4%) as was G2/3 carboplatin hypersensitivity (47% vs 21%).

Conclusions: With this schedule, the addition of decitabine appears to reduce rather than increase the efficacy of carboplatin in partially platinum-sensitive ovarian cancer and is difficult to deliver. Patient-selection strategies, different schedules and other demethylating agents should be considered in future combination studies.

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It is now recognised that inactive lifestyles underpin much of the disease burden evident in the richer nations of the world. Indeed, the WHO has identified physical inactivity as a 'global public health problem' and has established minimum physical activity (PA) targets for people at different stages of the life-course. Yet, according to WHO, just under 1/3 of working age adults across the globe meet those targets and it is not at all clear how the disjunction between the recommendations of policy makers and the behaviour of ordinary people might be surmounted. Using an opportunity to examine the impact of an urban regeneration project on community residents in East Belfast (Northern Ireland) this paper examines the views of some 113 people on how to increase rates of PA in an area of multiple deprivation. The results of the analysis suggest that lay people rarely consider PA as a discrete issue, or one that centres on individuals and their motivation, but rather as one component in a complex web of concerns, processes and events that include such things as the actions of neighbours and relatives, material and political environments, vandalism, violence, and the weather. We explore and unravel the nature of those concerns using novel methods of content analysis that generate 'issue webs'. Particular attention is paid to the ways in which lay people conceptualize 'activity' and to the manner in which they point to ways of encouraging activity that are rooted in everyday life rather than in the corpocentric, agent-centred and often sport dominated strategies favoured by local policy makers. Our results support those who argue that interventions to increase rates of PA need to move beyond behavioural approaches that focus on individuals and consider the social, political and material contexts in which 'activity' occurs.

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Using first-principles molecular dynamics simulations, we have investigated the notion that amino acids can play a protective role when DNA is exposed to excess electrons produced by ionizing radiation. In this study we focus on the interaction of glycine with the DNA nucleobase thymine. We studied thymine-glycine dimers and a condensed phase model consisting of one thymine molecule solvated in amorphous glycine. Our results show that the amino acid acts as a protective agent for the nucleobase in two ways. If the excess electron is initially captured by the thymine, then a proton is transferred in a barrier-less way from a neighboring hydrogen-bonded glycine. This stabilizes the excess electron by reducing the net partial charge on the thymine. In the second mechanism the excess electron is captured by a glycine, which acts as a electron scavenger that prevents electron localization in DNA. Both these mechanisms introduce obstacles to further reactions of the excess electron within a DNA strand, e.g. by raising the free energy barrier associated with strand breaks.

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This report concerns the provisions and practices on betting-related match fixing in sports
within the 28 Member States. Carried out in late 2013/early 2014, respondents in each Member
State reported on that state’s gambling-related provisions in respect of football and tennis and
(in each country) a third sport determined on the basis of either its popularity (in terms of
participation or television viewing) or the existence of betting-related “scandals” in that sport
within that particular jurisdiction. Those reports helped the authors to compare the Member
States’ regulatory and self-regulatory frameworks relating to risk assessment and conflict of
interest management, with a view to indicating areas of best practice, identifying particularly
good legislative frameworks and highlighting areas where change was either desirable or
necessary. While some individual Member States have legislation which might provide
templates that others could adapt for their own use, the authors were not convinced that “more
law”, whether at the national or European level, was desirable. Rather, more effective
cooperation among the stakeholders was identified as being more likely to provide tangible
benefits than would new legal frameworks.

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The nature of photon interaction and reaction pH can have significant impacts on semiconductor photocatalysis. This paper describes the effect of pH on the photonic efficiency of photocatalytic reactions in the aqueous phase using TiO2 catalysts. The reactor was irradiated using periodic illumination with UV-LEDs through control of the illumination duty cycle (γ) through a series of light and dark times (Ton/Toff). Photonic efficiencies for methyl orange degradation were found to be comparable at high γ irrespective of pH. At lower γ, pH effects on photonic efficiency were very distinct across acidic, neutral and alkaline pH indicating an effect of complementary parameters. The results suggest photonic efficiency is greatest as illumination time, Ton approaches interfacial electron-transfer characteristic time which is within the range of this study or charge-carrier lifetimes upon extrapolation and also when electrostatic attraction between surface-trapped holes, {TiIVOH}ads+ and substrate molecules is strongest.

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The use of controlled periodic illumination with UV LEDs for enhancing photonic efficiency of photocatalytic decomposition processes in water has been investigated using methyl orange as a model compound. The impact of the length of light and dark time periods (T ON/T OFF times) on photodegradation and photonic efficiency using a UV LED-illuminated photoreactor has been studied. The results have shown an inverse dependency of the photonic efficiency on duty cycle and a very little effect on T ON or T OFF time periods, indicating no effect of rate-limiting steps through mass diffusion or adsorption/desorption in the reaction. For this reactor, the photonic efficiency under controlled periodic illumination (CPI) matches to that of continuous illumination, for the same average UV light intensities. Furthermore, under CPI conditions, the photonic efficiency is inversely related to the average UV light intensity in the reactor, in the millisecond time regime. This is the first study that has investigated the effect of controlled periodic illumination using ultra band gap UV LED light sources in the photocatalytic destruction of dye compounds using titanium dioxide. The results not only enhance the understanding of the effect of periodic illumination on photocatalytic processes but also provide a greater insight to the potential of these light sources in photocatalytic reactions. 

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Introduction: Because a dose–response relationship is characteristic of conventional chemotherapy, this concept is widely used for the development of novel cytotoxic (CTX) drugs. However, the need to reach the MTD to obtain optimal benefit with molecularly targeted agents (MTA) is controversial. In this study, we evaluated the relationship between dose and efficacy in a large cohort of phase I patients with solid tumors.

Experimental Design: We collected data on 1,182 consecutive patients treated in phase I trials in 14 European institutions in 2005–2007. Inclusion criteria were: (i) patients treated within completed single-agent studies in which a maximum-administered dose was defined and (ii) RECIST/survival data available.

Results: Seventy-two percent of patients were included in trials with MTA (N = 854) and 28% in trials with CTX (N = 328). The objective response (OR) rate was 3% and disease control at 6 months was 11%. OR for CTX was associated with higher doses (median 92% of MTD); this was not the case for MTA, where patients achieving OR received a median of 50% of MTD. For trials with MTA, patients treated at intermediate doses (40%–80%) had better survival compared with those receiving low or high doses (P = 0.038). On the contrary, there was a direct association between higher dose and better OS for CTX agents (P = 0.003).

Conclusion: Although these results support the development of novel CTX based on MTD, we found no direct relationship between higher doses and response with MTA in unselected patients. However, the longest OS was seen in patients treated with MTA at intermediate doses (40%–80% of MTD)

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Sheep transport within Europe involves 9.5 million animals yearly, 63% of which travel over longjourneys (> 8 h). Livestock transport, particularly over long journeys, gives rise to concern about the welfare of transported animals. The European Commission stimulates the development of market-oriented animal welfare standards for all phases of livestock production, providing an alternative to the 'regulatory approach'. This study aimed to develop and test a new sheep welfare assessment protocol to be used following transport, irrespective of the journey purpose. The protocol included outcome (animal-based measures) and input variables (resource-based and management-based measures), being welfare-relevant aspects of both transport and unloading procedures. Weighted Cohen's Kappa and Heiss' Kappa index of agreement were calculated to evaluate the raters accuracy and the inter-observer reliability.Overall, good agreement levels were found. The protocol was tested on 40 commercial transports arriving at previously selected assembly centres and slaughterhouses in Italy and Greece. The protocol was found to be feasible when applied to commercial transports, allowing for a comprehensive and quick sheep welfare assessment during unloading, without impairing stockman work. Univariate analysis was carried out to evaluate associations between outcome and input variables. In this study, significant association between outcome measures and risk factors were identified when associated to unloading procedures but not to travel conditions. In collaboration with the relevant stakeholders, this protocol might be developed into a tool for routine checks for certification purposes and could provide direct feedback to all professionals involved in animal transportation on the weaknesses and strengths of their work.

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This thesis analyses the concept of Political Will, suggests its operationalization and establishes a typological theory that provides the necessary support for the diverse strategies of action of a leader. It claims that political leadership styles articulate a choice of action that results from the Political Will of a leader, which is determined by his intention and his discerned possibilities to act. One main research question guided our research: How does a political leader select and change his leadership style? The most illustrative literature on political leadership is reviewed and the characteristics of democratic governance are analyzed. This is followed by an overview of the most noteworthy theories on the theme and a claim for the need of concept coherence, given the multiplicity of the existent standpoints. After that, we concentrate on leadership styles, with a focus on the local governance context. Human action and intentionality are addressed with particular attention, as well as the motivational drivers for action, in order to advance a conceptualization of Political Will through two dimensions: intention and possibility. This analysis led to a number of relevant propositions: (1) Political Will ‘exists’ when the agent has the intent and the possibility to act; (2) these two dimensions ‘translate’ simultaneously what the agent believes he must do and can do; (3) Intention and possibility reflect diverse but limited worldviews; (4) political leadership styles result from the agent’s Political Will; (5) different combinations of the expected and actual worldviews result in different leadership styles; and (6) political leadership styles can change accordingly to several strategies which allow conformity or reflect reaction to worldviews. We suggested the operationalization of the two dimensions of Political Will through the analytical tool of Grid-group Theory, which provided the identification of the heuristic devices that allowed further comprehension on the subjectivity of the agent’s choice. Four standard property spaces – representing four types of leadership styles – result from a preliminary approach to this process. Afterwards, and because these dimensions operate simultaneously, we advance on the analysis and suggest some plausible heuristical conflicts to happen and describe which consequences, strategies and type migrations are conceivable. An inclusive and more complete set of resulting property spaces renders fourteen different types of leadership styles and sixty different predictable causal paths that result from the expected migration strategies. Case-studies were conducted as plausibility probes designed to provide improvements to our theoretical claims and addressed the cases we selected for research purposes: Portuguese Mayors. The findings from five case studies are discussed and the probable impact and congruence of each with the theoretical claims are assessed. The communalities of the causal mechanisms related to the function of intention and possibility as the dimensions of Political Will and their role in explaining different leadership styles are, finally, addressed. To conclude, we advance some repercussions, mainly in the public policies field of research, and suggest a number of different and necessary paths for further work.

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A associação simbiótica de plantas leguminosas com bactérias do género Rhizobium é o maior e mais eficiente contribuinte de azoto fixado biologicamente (Somasegaran e Hoben, 1994; Zahran, 1999). No entanto, o constante aumento da poluição em solos agrícolas, nomeadamente a contaminação por metais devido à aplicação de fertilizantes e de lamas, está a tornar-se um problema ambiental cada vez mais preocupante (Alloway, 1995a; Giller et al., 1998; Permina et al., 2006; Thorsen et al., 2009; Wani et al., 2008), influenciando de forma negativa a persistência destas bactérias nos solos agrícolas, assim como a sua eficácia de nodulação (Broos et al., 2005; Wani et al., 2008;. Zhengwei et al., 2005). Desta forma, o estudo dos mecanismos de tolerância de Rhizobium a metais tornou-se uma área de investigação de elevada importância. Com o trabalho apresentado nesta tese pretendeu-se perceber melhor a tolerância Rhizobium leguminosarum ao cádmio (Cd), dando particular atenção a um mecanismo de tolerância previamente descrito em R. leguminosarum (Lima et al., 2006): a complexação intracelular de Cd pelo tripéptido glutationa (GSH). Assim, o principal objectivo deste trabalho foi perceber melhor qual a importância deste mecanismo nos níveis de tolerância de rizóbio ao Cd. Como já tinha sido descrito em trabalhos anteriores (Figueira et al., 2005; Lima et al., 2006), foi possível verificar que a estirpe mais tolerante ao metal apresenta níveis mais elevados de Cd e GSH intracelulares. Demonstrou-se ainda que a tolerância ao Cd está dependente da maior eficiência no mecanismo de complexação observada na estirpe tolerante, logo durante as primeiras 12 h de crescimento. Gomes et al. (2002) verificou que a acumulação de complexos GSH-Cd no citoplasma inibe a entrada de metal na célula. Como neste trabalho se observou um aumento nos níveis de Cd intracelular na estirpe tolerante ao longo do tempo, surgiu a hipótese dos complexos serem excretados para o espaço periplasmático. Os elevados níveis de GSH e de Cd determinados no espaço periplasmático corroboraram esta hipótese. Neste trabalho demonstrou-se ainda que a eficácia do mecanismo de complexação, depende da actividade enzimática de uma isoforma específica de GST, que apresentou um elevado acréscimo de actividade na presença do metal. Desta forma, os resultados desta tese indicam que, a maior tolerância de R. leguminosarum ao Cd, depende da capacidade das estirpes para induzir a síntese de GSH na presença de Cd e, simultaneamente aumentar a actividade enzimática da GST específica, optimizando assim o mecanismo de complexação de Cd intracelular.

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Background: The present study investigated whether prochlorperazine affects vestibular-ocular reflex (VOR) and vestibulo-perceptual function. Methods: We studied 12 healthy naïve subjects 3 hours after a single dose of oral prochlorperazine 5mg in a randomised, placebo-controlled, double-blind, cross-over study in healthy young subjects. Two rotational tests in yaw were used: 1) a Threshold task investigating perceptual motion detection and nystagmic thresholds (acceleration steps of 0.5deg/s/s) and 2) Suprathreshold responses to velocity steps of 90deg/s in which vestibulo-ocular (VO) and vestibulo-perceptual (VP) time constants of decay, as well as VOR gain, were measured. Results: Prochlorperazine had no effect upon any measure of nystagmic or perceptual vestibular function compared to placebo. This lack of effects on vestibular-mediated motion perception suggests that the drug is likely to act more as an antiemetic than as an anti-vertiginous agent.