Challenges with minimising mercury pollution in the small-scale gold mining sector: Experiences from the Guianas

This paper examines the barriers to mitigating mercury pollution at small-scale gold mines in the Guianas (Guyana, French Guiana and Suriname), and prescribes recommendations for overcoming these obstacles. Whilst considerable attention has been paid to analysing the environmental impacts of operations in the region, minimal research has been undertaken to identify appropriate policy and educational initiatives for addressing the mounting mercury problem. Findings from recent fieldwork and selected interviews with operators from Guyanese and Surinamese gold mining regions reveal that legislative incapacity, the region's varied industry policy stances, various technological problems, and low environmental awareness on the part of communities are impeding efforts to facilitate improved mercury management at small-scale gold mines in the Guianas. Marked improvements can be achieved, however, if legislation, particularly that pertaining to mercury, is harmonised in the region; educational seminars continue to be held in important mining districts; and additional outlets for disseminating environmental equipment and mercury-free technologies are provided.

Effect of micronutrient supplementation on mood in nursing home residents

One third of older people in nursing and/or residential homes have significant symptoms of depression. In younger people, deficiencies in selenium, vitamin C and folate are associated with depression. This study examines the association between micronutrient status and mood before and after supplementation. The objective was to determine whether the administration of selenium, vitamin C and folate improved mood in frail elderly nursing home residents. Mood was assessed using the Hospital Anxiety and Depression rating scale (HAD), and Montgomery-Asberg Depression Rating Scale (MADRS). Micronutrient supplementation was provided for 8 weeks in a double-blinded randomised controlled trial. Significant symptoms of depression (29%) and anxiety (24%) were found at baseline. 67% of patients had low serum concentrations of vitamin C, but no-one was below the reference range for selenium. Depression was significantly associated with selenium levels, but not with folate or vitamin C levels. No individual with a HAD depression score of >= 8, had selenium levels >1.2 mu M. In those patients with higher HAD depression scores, there was a significant reduction in the score and a significant increase in serum selenium levels after 8 weeks of micronutrient supplementation. Placebo group scores were unchanged. This small study concluded that depression was associated with low levels of selenium in frail older individuals. Following 8 weeks of micronutrient supplementation, there was a significant increase in selenium levels and improved symptoms of depression occurred in a subgroup. Copyright (C) 2008 S. Karger AG, Basel

Post-partum depression and infant growth in a South African peri-urban settlement

Aim: To examine the association between maternal post-natal depression and infant growth. Background: Infant growth has recently been shown, in two studies from South Asia, to be adversely affected by maternal depression in the early post-partum period. It is uncertain whether a similar association obtains in developing countries outside Asia. Method: A sample of 147 mother–infant dyads was recruited from a peri-urban settlement outside Cape Town and seen at 2 and 18 months post partum. Results: No clear effect of post-partum depression on infant growth was found. Although maternal depression at 2 months was found to be associated with lower infant weight at 18 months, when birthweight was considered this effect disappeared. Conclusions: Possible explanations for the non-replication of the South Asian findings are considered.

Family interventions in psychosis: a scale to measure therapist adherence

The efficacy of family interventions in psychosis is well documented. UK and USA schizophrenia treatment guidelines advocate the practice of family interventions within routine clinical services. However, less attention has been paid to the study of treatment fidelity and the tools used in its assessment. This study reports the inter-rater reliability of a new scale: Family Intervention in Psychosis-Adherence Scale (FIPAS). This measure is designed to assess therapist adherence to the Kuipers et al. (2002) family intervention in psychosis treatment manual. Reliability ratings were based on a sample of thirteen audiotapes drawn from a randomized controlled trial of family intervention. The results indicated that the majority of items of the FIPAS had acceptable levels of inter-rater reliability. The findings are discussed in terms of their implications for the training and monitoring of the effectiveness of practitioners for family interventions in psychosis.

Maternal depression and psychiatric outcomes in adolescent offspring: a13-year longitudinal study

Background: Maternal postnatal depression (PND) has been associated with adverse outcomes in young children, but an association with longer-term psychiatric disorder has not been demonstrated. We present the preliminary findings of a 13-year longitudinal study. Methods: In the course of a prospective longitudinal study, we examined DSM-IV Axis I disorders in 13-year-old adolescents who had (n=53) or had not (n=41) been exposed to maternal PND. We also detailed the occurrence of depression in mothers throughout the 13-year follow-up period. Results: Maternal PND was associated with higher rates of affective disorders in adolescent offspring. However, mothers who developed PND were also substantially more likely than those who did not to experience depression subsequently, a fact that contributed to the development of depressive disorder in offspring. Maternal PND was associated with increased risk for depression in adolescent offspring only if there had also been later episodes of maternal depression. In contrast, anxiety disorders in offspring were elevated in the maternal PND group regardless of the occurrence of subsequent maternal depression. Limitations: Due to the modest sample size and consequently limited power, findings must be regarded as preliminary. Conclusions: The particular association between early maternal depression and anxiety disorders in offspring was consistent with theories that emphasise the primacy of early environmental exposures. This position was not supported with respect to offspring depressive disorder, where overall duration of maternal depression was a significant factor. PND was associated with recurrent episodes of depression in the majority of cases, underlining the need for monitoring of this population beyond the postnatal period. (c) 2006 Elsevier B.V. All rights reserved.

Rossby waves and two-dimensional turbulence in a large-scale zonal jet

The theory of homogeneous barotropic beta-plane turbulence is here extended to include effects arising from spatial inhomogeneity in the form of a zonal shear flow. Attention is restricted to the geophysically important case of zonal flows that are barotropically stable and are of larger scale than the resulting transient eddy field. Because of the presumed scale separation, the disturbance enstrophy is approximately conserved in a fully nonlinear sense, and the (nonlinear) wave-mean-flow interaction may be characterized as a shear-induced spectral transfer of disturbance enstrophy along lines of constant zonal wavenumber k. In this transfer the disturbance energy is generally not conserved. The nonlinear interactions between different disturbance components are turbulent for scales smaller than the inverse of Rhines's cascade-arrest scale κβ[identical with] (β0/2urms)½ and in this regime their leading-order effect may be characterized as a tendency to spread the enstrophy (and energy) along contours of constant total wavenumber κ [identical with] (k2 + l2)½. Insofar as this process of turbulent isotropization involves spectral transfer of disturbance enstrophy across lines of constant zonal wavenumber k, it can be readily distinguished from the shear-induced transfer which proceeds along them. However, an analysis in terms of total wavenumber K alone, which would be justified if the flow were homogeneous, would tend to mask the differences. The foregoing theoretical ideas are tested by performing direct numerical simulation experiments. It is found that the picture of classical beta-plane turbulence is altered, through the effect of the large-scale zonal flow, in the following ways: (i) while the turbulence is still confined to K Kβ, the disturbance field penetrates to the largest scales of motion; (ii) the larger disturbance scales K < Kβ exhibit a tendency to meridional rather than zonal anisotropy, namely towards v2 > u2 rather than vice versa; (iii) the initial spectral transfer rate away from an isotropic intermediate-scale source is significantly enhanced by the shear-induced transfer associated with straining by the zonal flow. This last effect occurs even when the large-scale shear appears weak to the energy-containing eddies, in the sense that dU/dy [double less-than sign] κ for typical eddy length and velocity scales.

Self-consistent wave-particle interactions in dispersive scale long-period field-line-resonances

Using 1D Vlasov drift-kinetic computer simulations, it is shown that electron trapping in long period standing shear Alfven waves (SAWs) provides an efficient energy sink for wave energy that is much more effective than Landau damping. It is also suggested that the plasma environment of low altitude auroral-zone geomagnetic field lines is more suited to electron acceleration by inertial or kinetic scale Alfven waves. This is due to the self-consistent response of the electron distribution function to SAWs, which must accommodate the low altitude large-scale current system in standing waves. We characterize these effects in terms of the relative magnitude of the wave phase and electron thermal velocities. While particle trapping is shown to be significant across a wide range of plasma temperatures and wave frequencies, we find that electron beam formation in long period waves is more effective in relatively cold plasma.

Intrastriatal transplantation of adult human neural crest-derived stem cells improves functional outcome in parkinsonian rats

Parkinson's disease (PD) is considered the second most frequent and one of the most severe neurodegenerative diseases, with dysfunctions of the motor system and with nonmotor symptoms such as depression and dementia. Compensation for the progressive loss of dopaminergic (DA) neurons during PD using current pharmacological treatment strategies is limited and remains challenging. Pluripotent stem cell-based regenerative medicine may offer a promising therapeutic alternative, although the medical application of human embryonic tissue and pluripotent stem cells is still a matter of ethical and practical debate. Addressing these challenges, the present study investigated the potential of adult human neural crest-derived stem cells derived from the inferior turbinate (ITSCs) transplanted into a parkinsonian rat model. Emphasizing their capability to give rise to nervous tissue, ITSCs isolated from the adult human nose efficiently differentiated into functional mature neurons in vitro. Additional successful dopaminergic differentiation of ITSCs was subsequently followed by their transplantation into a unilaterally lesioned 6-hydroxydopamine rat PD model. Transplantation of predifferentiated or undifferentiated ITSCs led to robust restoration of rotational behavior, accompanied by significant recovery of DA neurons within the substantia nigra. ITSCs were further shown to migrate extensively in loose streams primarily toward the posterior direction as far as to the midbrain region, at which point they were able to differentiate into DA neurons within the locus ceruleus. We demonstrate, for the first time, that adult human ITSCs are capable of functionally recovering a PD rat model.

Improving mood with psychoanalytic and cognitive therapies (IMPACT): a pragmatic effectiveness superiority trial to investigate whether specialised psychological treatment reduces the risk for relapse in adolescents with moderate to severe unipolar depression: study protocol for a randomised controlled trial

Background Up to 70% of adolescents with moderate to severe unipolar major depression respond to psychological treatment plus Fluoxetine (20-50 mg) with symptom reduction and improved social function reported by 24 weeks after beginning treatment. Around 20% of non responders appear treatment resistant and 30% of responders relapse within 2 years. The specific efficacy of different psychological therapies and the moderators and mediators that influence risk for relapse are unclear. The cost-effectiveness and safety of psychological treatments remain poorly evaluated. Methods/Design Improving Mood with Psychoanalytic and Cognitive Therapies, the IMPACT Study, will determine whether Cognitive Behavioural Therapy or Short Term Psychoanalytic Therapy is superior in reducing relapse compared with Specialist Clinical Care. The study is a multicentre pragmatic effectiveness superiority randomised clinical trial: Cognitive Behavioural Therapy consists of 20 sessions over 30 weeks, Short Term Psychoanalytic Psychotherapy 30 sessions over 30 weeks and Specialist Clinical Care 12 sessions over 20 weeks. We will recruit 540 patients with 180 randomised to each arm. Patients will be reassessed at 6, 12, 36, 52 and 86 weeks. Methodological aspects of the study are systematic recruitment, explicit inclusion criteria, reliability checks of assessments with control for rater shift, research assessors independent of treatment team and blind to randomization, analysis by intention to treat, data management using remote data entry, measures of quality assurance, advanced statistical analysis, manualised treatment protocols, checks of adherence and competence of therapists and assessment of cost-effectiveness. We will also determine whether time to recovery and/or relapse are moderated by variations in brain structure and function and selected genetic and hormone biomarkers taken at entry. Discussion The objective of this clinical trial is to determine whether there are specific effects of specialist psychotherapy that reduce relapse in unipolar major depression in adolescents and thereby costs of treatment to society. We also anticipate being able to utilise psychotherapy experience, neuroimaging, genetic and hormone measures to reveal what techniques and their protocols may work best for which patients.

The specific role of relationship life events in the onset of depression during pregnancy and the postpartum

Background The precipitating role of life events in the onset of depression is well-established. The present study sought to examine whether life events hypothesised to be personally salient would be more strongly associated with depression than other life events. In a sample of women making the first transition to parenthood, we hypothesised that negative events related to the partner relationship would be particularly salient and thus more strongly predictive of depression than other events. Methods A community-based sample of 316 first-time mothers stratified by psychosocial risk completed interviews at 32 weeks gestation and 29 weeks postpartum to assess dated occurrence of life events and depression onsets from conception to 29 weeks postpartum. Complete data was available from 273 (86.4%). Cox proportional hazards regression was used to examine risk for onset of depression in the 6 months following a relationship event versus other events, after accounting for past history of depression and other potential confounders. Results 52 women (19.0%) experienced an onset of depression between conception and 6 months postpartum. Both relationship events (Hazard Ratio = 2.1, p = .001) and other life events (Hazard Ratio = 1.3, p = .020) were associated with increased risk for depression onset; however, relationship events showed a significantly greater risk for depression than did other life events (p = .044). Conclusions The results are consistent with the hypothesis that personally salient events are more predictive of depression onset than other events. Further, they indicate the clinical significance of events related to the partner relationship during pregnancy and the postpartum.