Balancing macronutrient stoichiometry to alleviate eutrophication

Reactive nitrogen (N) and phosphorus (P) inputs to surface waters modify aquatic environments, affect public health and recreation. Source controls dominate eutrophication management, whilst biological regulation of nutrients is largely neglected, although aquatic microbial organisms have huge potential to process nutrients. The stoichiometric ratio of organic carbon (OC) to N to P atoms should modulate heterotrophic pathways of aquatic nutrient processing, as high OC availability favours aquatic microbial processing. Heterotrophic microbial processing removes N by denitrification and captures N and P as organically-complexed, less eutrophying forms. With a global data synthesis, we show that the atomic ratios of bioavailable dissolved OC to either N or P in rivers with urban and agricultural land use are often distant from a "microbial optimum". This OC-deficiency relative to high availabilities of N and P likely overwhelms within-river heterotrophic processing. We propose that the capability of streams and rivers to retain N and P may be improved by active stoichiometric rebalancing. Although autotrophic OC production contributes to heterotrophic rates substantial control on nutrient processing from allochthonous OC is documented for N and an emerging field for P. Hence, rebalancing should be done by reconnecting appropriate OC sources such as wetlands and riparian forests that have become disconnected from rivers concurrent with agriculture and urbanisation. However, key knowledge gaps require research prior to the safe implementation of this approach in management: (i) to evaluate system responses to catchment inputs of dissolved OC forms and amounts relative to internal production of autotrophic dissolved OC and aquatic and terrestrial particulate OC and (ii) evaluate risk factors in anoxia-mediated P desorption with elevated OC scenarios. Still, we find stoichiometric rebalancing through reconnecting landscape beneficial OC sources has considerable potential for river management to alleviate eutrophication, improve water quality and aquatic ecosystem health, if augmenting nutrient source control.

Turning Modes of Production Inside Out

Marxist theory has by now largely abandoned the (seriously flawed) notion of the ‘mode of production’, but doing so has only encouraged a trend to abandon much of what was radical about it and naturalize capitalist categories. This article argues a better conceived notion of a mode of production - one that recognizes the primacy of human production, and hence a more sophisticated notion of materialism - might still have something to show us: notably, that capitalism, or at least industrial capitalism, has far more in common with, and is historically more closely linked with, chattel slavery than most of us had ever imagined.

Fetishism as social creativity

Originally, the term ‘fetishes’ was used by European merchants to refer to objects employed in West Africa to make and enforce agreements, often between people with almost nothing in common. They thus provide an interesting window on the problem of social creativity - especially since in classic Marxist terms they were surprisingly little fetishized. Starting with an appreciation and critique of William Pietz’s classic work on the subject, and reconsidering classic cases of Tiv spheres of exchange and BaKongo sculpture, this article aims to reimagine African fetishes, and fetishes in general, as ways of creating new social relations.

Don't Step on the Tiger's Tail: A Mixed Methods Study of the Relationship Between Adult Impact of Childhood Adversity and Use of Coping Strategies

A mixed methods study examined the relationship between childhood adversity (ACE) and coping among individuals grouped by perceived impact of ACE in adulthood. Groups did not differ on mean total ACE scores and total ACE score was not associated with any coping strategy. Differences between groups were found in 6 of 14 coping strategies. Planning and active coping were endorsed the most by both groups, despite their being used in significantly different amounts and in different ways. How individuals with ACE rate its impact in their current lives is a significant factor in the use and meaning of coping strategies.

Land-use impacts on fatty acid profiles of suspended particulate organic matter along a larger tropical river

Land-use change, such as agricultural expansion and urbanization, can affect riverine biological diversity and ecosystem functioning. Identifying the major stressors associated with catchment land-use change is a prerequisite for devising successful river conservation and restoration strategies. Here, we analyzed land-use effects on the fatty acid (FA) composition and concentrations in suspended particulate organic matter (SPOM) along a fourth-order tropical river, the Rio das Mortes. Thereby, we aimed at testing the potential of fatty acids in riverine suspended particulate organic matter (SPOM-FAs) as indicators of land-use change in tropical catchments, and at identifying major human impacts on the biochemical composition of SPOM, which represents an important basal energy and organic matter resource for aquatic consumers. River water SPOM and total FA concentrations ranged between 2.8 and 10.2mg dry weight(DW)L(-1) and between 130.6 and 268.2μg DW L(-1), respectively, in our study. Urbanization was the only land-use category correlating with both FA composition and concentrations, despite its low contribution to whole catchment (1.5-5.6%) and riparian buffer land cover (1.7-6.6%). Higher concentrations of saturated FAs, especially C16:0 and C18:0, which are the main components of domestic sewage, were observed at sampling stations downstream of urban centers, and were highly correlated to urbanization, especially within the 60m riparian buffer zone. Compared to water chemical characteristics (inorganic nutrients, dissolved oxygen, pH, and specific conductance) and river habitat structural integrity, FA variables exhibited a higher variability along the investigated river and were more strongly correlated to urban land use, suggesting that SPOM-FA profiles may be an efficient indicator of urban land-use impacts on larger tropical rivers. High total FA concentrations in the SPOM of urbanized tropical rivers may represent high-energy biochemical subsidies to food webs, potentially leading to changes in functional ecosystem characteristics, such as bacterial and suspension-feeder production.

Direct and indirect effects of childhood adversity on adult depression

Exposure to adverse events in childhood is a predictor of subsequent exposure to adverse events in adulthood, and both are predictors of depression in adults. The degree to which adult depression has a direct effect of childhood adversity versus an indirect effect mediated by adult adversity has not previously been reported. We report data collected from 210 adult participants regarding childhood and adult adversity and current symptoms of depression. Mediation of the relationship between childhood adversity and adult depression by adult adversity was statistically assessed to evaluate the relative direct and indirect effects of childhood adversity on current depression levels in adults. Both the direct effect of childhood adversity on adult depression and the indirect effect, mediated by adulthood events, were significant. Therefore, partial mediation of the relationship between childhood adversity and adult symptoms of depression by adult adverse events was found in the sample. Implications for treatment are presented.

Effectiveness and cost of olanzapine and haloperidol in the treatment of schizophrenia: a randomized controlled trial

CONTEXT

Although olanzapine has been widely adopted as a treatment of choice for schizophrenia, its long-term effectiveness and costs have not been evaluated in a controlled trial in comparison with a standard antipsychotic drug.

OBJECTIVE

To evaluate the effectiveness and cost impact of olanzapine compared with haloperidol in the treatment of schizophrenia.

DESIGN AND SETTING

Double-blind, randomized controlled trial with randomization conducted between June 1998 and June 2000 at 17 US Department of Veterans Affairs medical centers.

PARTICIPANTS

Three hundred nine patients with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnosis of schizophrenia or schizoaffective disorder, serious symptoms, and serious dysfunction for the previous 2 years. Fifty-nine percent fully completed and 36% partially completed follow-up assessments.

INTERVENTIONS

Patients were randomly assigned to receive flexibly dosed olanzapine, 5 to 20 mg/d, with prophylactic benztropine, 1 to 4 mg/d (n = 159); or haloperidol, 5 to 20 mg/d (n = 150), for 12 months.

MAIN OUTCOME MEASURES

Standardized measures of symptoms, quality of life, neurocognitive status, and adverse effects of medication. Veterans Affairs administrative data and interviews concerning non-VA service use were used to estimate costs from the perspective of the VA health care system and society as a whole (ie, consumption of all resources on behalf of these patients).

RESULTS

There were no significant differences between groups in study retention; positive, negative, or total symptoms of schizophrenia; quality of life; or extrapyramidal symptoms. Olanzapine was associated with reduced akathisia in the intention-to-treat analysis (P<.001) and with lower symptoms of tardive dyskinesia in a secondary analysis including only observations during blinded treatment with study drug. Small but significant advantages were also observed on measures of memory and motor function. Olanzapine was also associated with more frequent reports of weight gain and significantly greater VA costs, ranging from 3000 dollars to 9000 dollars annually. Differences in societal costs were somewhat smaller and were not significant.

CONCLUSION

Olanzapine does not demonstrate advantages compared with haloperidol (in combination with prophylactic benztropine) in compliance, symptoms, extrapyramidal symptoms, or overall quality of life, and its benefits in reducing akathisia and improving cognition must be balanced with the problems of weight gain and higher cost.