Sustainable Management of Soil in Oil Palm Plantings: Proceedings of a Workshop held in Medan, Indonesia, 7–8 November 2013

Oil palm is a globally important source of vegetable oil, being used in a wide variety of foods and other products. For many tropical countries it is an economically important crop, fulfilling local demand for vegetable oil and generating large export incomes. It is grown by plantation companies and smallholder families; often in a nucleus or plasma system where the smallholders supply oil palm fruit to a centralised mill. As demand for vegetable oil increases, due to growing and increasingly wealthy populations, the industry is expanding rapidly onto new land and there is an increasing need for ecological intensification of production. To ensure continuous production into the future and to safeguard the condi¬tion of the broader environment it is crucial that the condition of the soil in oil palm plantations be maintained or improved. In our rapidly changing environ¬ment, new management approaches will be needed to optimise production and sustainability. Such advances will rely heavily on science- and system-based understanding of oil palm agroecosystems. This workshop brought together 41 scientists from 10 countries to discuss and advance sustainability of soil management in oil palm production systems. The workshop and subsequent proceedings covered a broad range of topics: soil types and properties; water and nutrient cycling; effects of organic resi¬dues; biogeochemical processes; biological processes; monitoring, modelling and assessment, and; synthesis and discussion. The papers produced during the workshop will be useful to scientists and managers throughout the tropics. I hope that the information and approaches discussed in this volume will be used widely, stimulating better understanding and care of vital soil resources

Modelling environmental impacts of agriculture, focusing on oil palm

Cultivation of crops affects the environment via flows of energy and materials. Impacts are felt in the atmosphere, hydrosphere, surrounding terrestrial ecosystems and the field itself. Models are useful tools for improving our understanding of the processes and predicting how they might be affected by changes in management. Current models range from simple indicators of risk or impact, based on empirical relationships, to dynamic process-based models. Increasingly complex and comprehensive models with increasing spatial and temporal resolution and extent are being developed, mostly by coupling diverse sub-models. This chapter reviews the range of models developed for oil palm systems, and discusses how other existing models might be adapted for oil palm

Psychophysical Investigations into the Role of Low-Threshold C Fibres in Non-Painful Affective Processing and Pain Modulation

We recently showed that C low-threshold mechanoreceptors (CLTMRs) contribute to touch-evoked pain (allodynia) during experimental muscle pain. Conversely, in absence of ongoing pain, the activation of CLTMRs has been shown to correlate with a diffuse sensation of pleasant touch. In this study, we evaluated (1) the primary afferent fibre types contributing to positive (pleasant) and negative (unpleasant) affective touch and (2) the effects of tactile stimuli on tonic muscle pain by varying affective attributes and frequency parameters. Psychophysical observations were made in 10 healthy participants. Two types of test stimuli were applied: stroking stimulus using velvet or sandpaper at speeds of 0.1, 1.0 and 10.0 cm/s; focal vibrotactile stimulus at low (20 Hz) or high (200 Hz) frequency. These stimuli were applied in the normal condition (i.e. no experimental pain) and following the induction of muscle pain by infusing hypertonic saline (5%) into the tibialis anterior muscle. These observations were repeated following the conduction block of myelinated fibres by compression of sciatic nerve. In absence of muscle pain, all participants reliably linked velvet-stroking to pleasantness and sandpaper-stroking to unpleasantness (no pain). Likewise, low-frequency vibration was linked to pleasantness and high-frequency vibration to unpleasantness. During muscle pain, the application of previously pleasant stimuli resulted in overall pain relief, whereas the application of previously unpleasant stimuli resulted in overall pain intensification. These effects were significant, reproducible and persisted following the blockade of myelinated fibres. Taken together, these findings suggest the role of low-threshold C fibres in affective and pain processing. Furthermore, these observations suggest that temporal coding need not be limited to discriminative aspects of tactile processing, but may contribute to affective attributes, which in turn predispose individual responses towards excitatory or inhibitory modulation of pain

Harnessing Wicked Problems in Multi-stakeholder Partnerships

Despite the burgeoning literature on the governance and impact of cross-sector partnerships in the past two decades, the debate on how and when these collaborative arrangements address globally relevant problems and contribute to systemic change remains open. Building upon the notion of wicked problems and the literature on governing such wicked problems, this paper defines harnessing problems in multi-stakeholder partnerships (MSPs) as the approach of taking into account the nature of the problem and of organizing governance processes accordingly. The paper develops an innovative analytical framework that conceptualizes MSPs in terms of three governance processes (deliberation, decision-making and enforce-ment) harnessing three key dimensions of wicked problems (knowledge uncertainty, value conflict and dynamic complexity). The Roundtable on Sustainable Palm Oil provides an illustrative case study on how this analytical framework describes and explains organizational change in partnerships from a problem-based perspective. The framework can be used to better understand and predict the complex relationships between MSP governance processes, systemic change and societal problems, but also as a guiding tool in (re-)organizing governance processes to continuously re-assess the problems over time and address them accordingly

An Alpha-Catulin Homologue Controls Neuromuscular Function through Localization of the Dystrophin Complex and BK Channels in Caenorhabditis elegans

The large conductance, voltage- and calcium-dependent potassium (BK) channel serves as a major negative feedback regulator of calcium-mediated physiological processes and has been implicated in muscle dysfunction and neurological disorders. In addition to membrane depolarization, activation of the BK channel requires a rise in cytosolic calcium. Localization of the BK channel near calcium channels is therefore critical for its function. In a genetic screen designed to isolate novel regulators of the Caenorhabditis elegans BK channel, SLO-1, we identified ctn-1, which encodes an α-catulin homologue with homology to the cytoskeletal proteins α-catenin and vinculin. ctn-1 mutants resemble slo-1 loss-of-function mutants, as well as mutants with a compromised dystrophin complex. We determined that CTN-1 uses two distinct mechanisms to localize SLO-1 in muscles and neurons. In muscles, CTN-1 utilizes the dystrophin complex to localize SLO-1 channels near L-type calcium channels. In neurons, CTN-1 is involved in localizing SLO-1 to a specific domain independent of the dystrophin complex. Our results demonstrate that CTN-1 ensures the localization of SLO-1 within calcium nanodomains, thereby playing a crucial role in muscles and neurons

LCA applied to perennial cropping systems: a review focused on the farm stage

International audienc

Chronic Hypoxia Impairs Muscle Function in the Drosophila Model of Duchenne's Muscular Dystrophy (DMD)

Duchenne's muscular dystrophy (DMD) is a severe progressive myopathy caused by mutations in the DMD gene leading to a deficiency of the dystrophin protein. Due to ongoing muscle necrosis in respiratory muscles late-stage DMD is associated with respiratory insufficiency and chronic hypoxia (CH). To understand the effects of CH on dystrophin-deficient muscle in vivo, we exposed the Drosophila model for DMD (dmDys) to CH during a 16-day ascent to the summit of Mount Denali/McKinley (6194 meters above sea level). Additionally, dmDys and wild type (WT) flies were also exposed to CH in laboratory simulations of high altitude hypoxia. Expression profiling was performed using Affymetrix GeneChips® and validated using qPCR. Hypoxic dmDys differentially expressed 1281 genes, whereas the hypoxic WT flies differentially expressed 56 genes. Interestingly, a number of genes (e.g. heat shock proteins) were discordantly regulated in response to CH between dmDys and WT. We tested the possibility that the disparate molecular responses of dystrophin-deficient tissues to CH could adversely affect muscle by performing functional assays in vivo. Normoxic and CH WT and dmDys flies were challenged with acute hypoxia and time-to-recover determined as well as subjected to climbing tests. Impaired performance was noted for CH-dmDys compared to normoxic dmDys or WT flies (rank order: Normoxic-WT ≈ CH-WT> Normoxic-dmDys> CH-dmDys). These data suggest that dystrophin-deficiency is associated with a disparate, pathological hypoxic stress response(s) and is more sensitive to hypoxia induced muscle dysfunction in vivo. We hypothesize that targeting/correcting the disparate molecular response(s) to hypoxia may offer a novel therapeutic strategy in DMD