Valuing water resources in developing countries: A semiparametric approach to valuation models

Valuation of projects for the preservation of water resources provides important information to policy makers and funding institutions. Standard contingent valuation models rely on distributional assumptions to provide welfare measures. Deviations from assumed and actual distribution of benefits are important when designing policies in developing countries, where inequality is a concern. This article applies semiparametric methods to obtain estimates of the benefit from a project for the preservation of an important Brazilian river basin. These estimates lead to significant differences from those obtained using the standard parametric approach.

Regulation of xylanase in Aspergillus phoenicis: a physiological and molecular approach

Microbial xylanolytic enzymes have a promising biotechnological potential, and are extensively applied in industries. In this study, induction of xylanolytic activity was examined in Aspergillus phoenicis. Xylanase activity induced by xylan, xylose or beta-methylxyloside was predominantly extracellular (93-97%). Addition of 1% glucose to media supplemented with xylan or xylose repressed xylanase production. Glucose repression was alleviated by addition of cAMP or dibutyryl-cAMP. These physiological observations were supported by a Northern analysis using part of the xylanase gene ApXLN as a probe. Gene transcription was shown to be induced by xylan, xylose, and beta-methylxyloside, and was repressed by the addition of 1% glucose. Glucose repression was partially relieved by addition of cAMP or dibutyryl cAMP.

Modelling the Distribution of Ischaemic Stroke-Specific Survival Time Using an EM-based Mixture Approach with Random Effects Adjustment

A two-component survival mixture model is proposed to analyse a set of ischaemic stroke-specific mortality data. The survival experience of stroke patients after index stroke may be described by a subpopulation of patients in the acute condition and another subpopulation of patients in the chronic phase. To adjust for the inherent correlation of observations due to random hospital effects, a mixture model of two survival functions with random effects is formulated. Assuming a Weibull hazard in both components, an EM algorithm is developed for the estimation of fixed effect parameters and variance components. A simulation study is conducted to assess the performance of the two-component survival mixture model estimators. Simulation results confirm the applicability of the proposed model in a small sample setting. Copyright (C) 2004 John Wiley Sons, Ltd.

A new approach to the synthesis of conjugated polymer-nanocrystal composites for heterojunction optoelectronics

We report a simple one pot process for the preparation of lead sulfide (PbS) nanocrystals in the conjugated polymer poly (2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV), and we demonstrate electronic coupling between the two components.

Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for the treatment of schizophrenia and related disorders

Background: The Royal Australian and New Zealand College of Psychiatrists is co-ordinating the development of clinical practice guidelines (CPGs) in psychiatry, funded under the National Mental Health Strategy (Australia) and the New Zealand Health Funding Authority. This paper presents CPGs for schizophrenia and related disorders. Over the past decade schizophrenia has become more treatable than ever before. A new generation of drug therapies, a renaissance of psychological and psychosocial interventions and a first generation of reform within the specialist mental health system have combined to create an evidence-based climate of realistic optimism. Progressive neuroscientific advances hold out the strong possibility of more definitive biological treatments in the near future. However, this improved potential for better outcomes and quality of life for people with schizophrenia has not been translated into reality in Australia. The efficacy-effectiveness gap is wider for schizophrenia than any other serious medical disorder. Therapeutic nihilism, under-resourcing of services and a stalling of the service reform process, poor morale within specialist mental health services, a lack of broad-based recovery and life support programs, and a climate of tenacious stigma and consequent lack of concern for people with schizophrenia are the contributory causes for this failure to effectively treat. These guidelines therefore tackle only one element in the endeavour to reduce the impact of schizophrenia. They distil the current evidence-base and make recommendations based on the best available knowledge. Method: A comprehensive literature review (1990-2003) was conducted, including all Cochrane schizophrenia reviews and all relevant meta-analyses, and a number of recent international clinical practice guidelines were consulted. A series of drafts were refined by the expert committee and enhanced through a bi-national consultation process. Treatment recommendations: This guideline provides evidence-based recommendations for the management of schizophrenia by treatment type and by phase of illness. The essential features of the guidelines are: (i) Early detection and comprehensive treatment of first episode cases is a priority since the psychosocial and possibly the biological impact of illness can be minimized and outcome improved. An optimistic attitude on the part of health professionals is an essential ingredient from the outset and across all phases of illness. (ii) Comprehensive and sustained intervention should be assured during the initial 3-5 years following diagnosis since course of illness is strongly influenced by what occurs in this 'critical period'. Patients should not have to 'prove chronicity' before they gain consistent access and tenure to specialist mental health services. (iii) Antipsychotic medication is the cornerstone of treatment. These medicines have improved in quality and tolerability, yet should be used cautiously and in a more targeted manner than in the past. The treatment of choice for most patients is now the novel antipsychotic medications because of their superior tolerability and, in particular, the reduced risk of tardive dyskinesia. This is particularly so for the first episode patient where, due to superior tolerability, novel agents are the first, second and third line choice. These novel agents are nevertheless associated with potentially serious medium to long-term side-effects of their own for which patients must be carefully monitored. Conventional antipsychotic medications in low dosage may still have a role in a small proportion of patients, where there has been full remission and good tolerability; however, the indications are shrinking progressively. These principles are now accepted in most developed countries. (vi) Clozapine should be used early in the course, as soon as treatment resistance to at least two antipsychotics has been demonstrated. This usually means incomplete remission of positive symptomatology, but clozapine may also be considered where there are pervasive negative symptoms or significant or persistent suicidal risk is present. (v) Comprehensive psychosocial interventions should be routinely available to all patients and their families, and provided by appropriately trained mental health professionals with time to devote to the task. This includes family interventions, cognitive-behaviour therapy, vocational rehabilitation and other forms of therapy, especially for comorbid conditions, such as substance abuse, depression and anxiety. (vi) The social and cultural environment of people with schizophrenia is an essential arena for intervention. Adequate shelter, financial security, access to meaningful social roles and availability of social support are essential components of recovery and quality of life. (vii) Interventions should be carefully tailored to phase and stage of illness, and to gender and cultural background. (viii) Genuine involvement of consumers and relatives in service development and provision should be standard. (ix) Maintenance of good physical health and prevention and early treatment of serious medical illness has been seriously neglected in the management of schizophrenia, and results in premature death and widespread morbidity. Quality of medical care for people with schizophrenia should be equivalent to the general community standard. (x) General practitioners (GPs)s should always be closely involved in the care of people with schizophrenia. However, this should be truly shared care, and sole care by a GP with minimal or no special Optimal treatment of schizophrenia requires a multidisciplinary team approach with a consultant psychiatrist centrally involved.

What is an effective health consumer? A convergent interviewing approach

This study is part of a larger project on the measurement of effective health consumers in the context of musculoskeletal illness. This complex issue involves the progressive nature of the disease, invisibility of the illness and attendant impairments, complexity of decision-making and negotiation, and urgent need to translate emergent evidence about treatment and management to patients and health professionals. We conducted indepth interviews with patients, family members, general practitioners, specialist clinicians, and health consumer advocates (N = 84) about effective consumers in this context, using a process of convergent interviewing, with convergence conducted within and across groups and countries. The initial set of themes included information seeking and adaptation, decision-making, roles of patients, GPs, and specialists and communication between them, importance of pain and impact of depression, impact of the social environment (including the invisibility of the disease and the need for a normal life), and coping strategies.

Teen Triple P: A universal approach to reducing risk factors for behavioural and emotional problems in adolescents at the transition to high school

Teen Triple P is a multilevel system of intervention that is designed to provide parents with specific strategies to promote the positive development of their teenage children as they make the transition into high school and through puberty. The program is based on a combination of education about the developmental needs of adolescents, skills training to improve communication and problem-solving, plus specific modules to deal with common problems encountered by parents and adolescents that can escalate into major conflict and violence. It is designed to increase the engagement of parents of adolescent and pre-adolescent children by providing them with easy access to evidencebased parenting advice and support. This paper presents data collected as part of a survey of over 1400 students in first year high school at 9 Brisbane schools. The survey instrument was constructed to obtain students' reports about behaviour which is known to be associated with their health and wellbeing, and also on the extent to which their parents promoted or discouraged such behaviour at home, at school, and in their social and recreational activities in the wider community. Selected data from the survey were extracted and presented to parents at a series of parenting seminars held at the schools to promote appropriate parenting of teenagers. The objectives were to provide parents with accurate data about teenagers' behaviour, and about teenagers' reports of how they perceived their parents' behaviour. Normative data on parent and teenager behaviour will be presented from the survey as well as psychometric data relating to the reliability and validity of this new measure. Implications of this strategy for increasing parent engagement in parenting programs that aim to reduce behavioural and emotional problems in adolescents will be discussed.

Exponential Rates of Convergence in the Ergodic Theorem: A Constructive Approach

We prove that, once an algorithm of perfect simulation for a stationary and ergodic random field F taking values in S(Zd), S a bounded subset of R(n), is provided, the speed of convergence in the mean ergodic theorem occurs exponentially fast for F. Applications from (non-equilibrium) statistical mechanics and interacting particle systems are presented.

An approach to the synthesis of furanoheliangolides through Diels-Alder reactions

The core structure of the natural sesquiterpene lactones furanoheliangolides, an 11-oxabicyclo[6.2.1]undecane system, was synthesized through a pathway involving two Diels-Alder reactions. (c) 2007 Elsevier Ltd. All rights reserved.

Molecular epidemiology: A multidisciplinary approach to understanding parasitic zoonoses

Sound application of molecular epidemiological principles requires working knowledge of both molecular biological and epidemiological methods. Molecular tools have become an increasingly important part of studying the epidemiology of infectious agents. Molecular tools have allowed the aetiological agent within a population to be diagnosed with a greater degree of efficiency and accuracy than conventional diagnostic tools. They have increased the understanding of the pathogenicity, virulence, and host-parasite relationships of the aetiological agent, provided information on the genetic structure and taxonomy of the parasite and allowed the zoonotic potential of previously unidentified agents to be determined. This review describes the concept of epidemiology and proper study design, describes the array of currently available molecular biological tools and provides examples of studies that have integrated both disciplines to successfully unravel zoonotic relationships that would otherwise be impossible utilising conventional diagnostic tools. The current limitations of applying these tools, including cautions that need to be addressed during their application are also discussed.(c) 2005 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

An evaluation of the evidence for linkages between mangroves and fisheries: A synthesis of the literature and identification of research directions

There is a widely held paradigm that mangroves are critical for sustaining production in coastal fisheries through their role as important nursery areas for fisheries species. This paradigm frequently forms the basis for important management decisions on habitat conservation and restoration of mangroves and other coastal wetlands. This paper reviews the current status of the paradigm and synthesises the information on the processes underlying these potential links. In the past, the paradigm has been supported by studies identifying correlations between the areal and linear extent of mangroves and fisheries catch. This paper goes beyond the correlative approach to develop a new framework on which future evaluations can be based. First, the review identifies what type of marine animals are using mangroves and at what life stages. These species can be categorised as estuarine residents, marine-estuarine species and marine stragglers. The marine-estuarine category includes many commercial species that use mangrove habitats as nurseries. The second stage is to determine why these species are using mangroves as nurseries. The three main proposals are that mangroves provide a refuge from predators, high levels of nutrients and shelter from physical disturbances. The recognition of the important attributes of mangrove nurseries then allows an evaluation of how changes in mangroves will affect the associated fauna. Surprisingly few studies have addressed this question. Consequently, it is difficult to predict how changes in any of these mangrove attributes would affect the faunal communities within them and, ultimately, influence the fisheries associated with them. From the information available, it seems likely that reductions in mangrove habitat complexity would reduce the biodiversity and abundance of the associated fauna, and these changes have the potential to cause cascading effects at higher trophic levels with possible consequences for fisheries. Finally, there is a discussion of the data that are currently available on mangrove distribution and fisheries catch, the limitations of these data and how best to use the data to understand mangrove-fisheries links and, ultimately, to optimise habitat and fisheries management. Examples are drawn from two relatively data-rich regions, Moreton Bay (Australia) and Western Peninsular Malaysia, to illustrate the data needs and research requirements for investigating the mangrove-fisheries paradigm. Having reliable and accurate data at appropriate spatial and temporal scales is crucial for mangrove-fisheries investigations. Recommendations are made for improvements to data collection methods that would meet these important criteria. This review provides a framework on which to base future investigations of mangrove-fisheries links, based on an understanding of the underlying processes and the need for rigorous data collection. Without this information, the understanding of the relationship between mangroves and fisheries will remain limited. Future investigations of mangrove-fisheries links must take this into account in order to have a good ecological basis and to provide better information and understanding to both fisheries and conservation managers.

Discontinuation of continuous renal replacement therapy: A post hoc analysis of a prospective multicenter observational study

Objectives: To describe current practice for the discontinuation of continuous renal replacement therapy in a multinational setting and to identify variables associated with successful discontinuation. The approach to discontinue continuous renal replacement therapy may affect patient outcomes. However, there is lack of information on how and under what conditions continuous renal replacement therapy is discontinued. Design: Post hoc analysis of a prospective observational study. Setting. Fifty-four intensive care units in 23 countries. Patients: Five hundred twenty-nine patients (52.6%) who survived initial therapy among 1006 patients treated with continuous renal replacement therapy. Interventions: None. Measurements and Main Results., Three hundred thirteen patients were removed successfully from continuous renal replacement therapy and did not require any renal replacement therapy for at least 7 days and were classified as the ""success"" group and the rest (216 patients) were classified as the ""repeat-RRT"" (renal replacement therapy) group. Patients in the ""success"" group had lower hospital mortality (28.5% vs. 42.7%, p < .0001) compared with patients in the ""repeat-RRT"" group. They also had lower creatinine and urea concentrations and a higher urine output at the time of stopping continuous renal replacement therapy. Multivariate logistic regression analysis for successful discontinuation of continuous renal replacement therapy identified urine output (during the 24 hrs before stopping continuous renal replacement therapy: odds ratio, 1.078 per 100 mL/day increase) and creatinine (odds ratio, 0.996 per mu mol/L increase) as significant predictors of successful cessation. The area under the receiver operating characteristic curve to predict successful discontinuation of continuous renal replacement therapy was 0.808 for urine output and 0.635 for creatinine. The predictive ability of urine output was negatively affected by the use of diuretics (area under the receiver operating characteristic curve, 0.671 with diuretics and 0.845 without diuretics). Conclusions. We report on the current practice of discontinuing continuous renal replacement therapy in a multinational setting. Urine output at the time of initial cessation (if continuous renal replacement therapy was the most important predictor of successful discontinuation, especially if occurring without the administration of diuretics. (Crit Care Med 2009; 37:2576-2582)