1,536 research outputs found
Nitrogen Dynamics and Nitrate Leaching in Intensive Vegetable Rotations in Highlands of Central Java, Indonesia
High rainfall intensity is major factor governing leaching process, where leaching is often the most important process of N loss from the field and lead to agricultural environmental pollution. In order to measure the movement of mineral-N in soil profile, a field research had been conducted in two sites of center vegetable farming area with six farmer cooperators in Central Java, Indonesia. Regular soil sampling was done from Improve Practice (IP) and Farmer Practice (FP) treatment for three planting seasons during 2007. Almost all treatments FP applied higher rate of N fertilizer compare to IP, but it was not reflected in N profile. Comparison of predicted and measured mineral N content was simulated using Burns α model, then the closeness of the estimation and measured calculated using Coefficient of Residual Mass (CRM) calculation as an indicator with 0 as ideal value. Out of 9 measurements of IP and FP treatment, eight and seven measurements had negative CRM representinga slight overestimation. The NO3-N loss estimated using the Burns α model for IP and FP was in average of 67% for IP and 71% for FP of total N fertilizer added or 67% for IP and 76% for FP of total-N surplus, respectively. The calculation of potential nitrate concentration (PNC) at 1 m soil depth at the end of the third season showed a high concentration with significant different of IP and FP having mean value of 59.8 and 82.5 mg N L-1. From the gathered data it was obvious that over N fertilization had negative effect to agricultural environment
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Centre for Food Policy at City, University of London response to the EFRA committee enquiry COVID-19 and food supply
The COVID19 pandemic has led to major disruptions in the UK and global food systems. The response by the UK government has been uncoordinated and inadequate. Our research highlights the broad range of policy input needed for food governance (at least 16 departments, plus multiple public bodies and agencies). Our research also highlights that while there have been efforts to connect this policy work in the past, food remains uncoordinated as a policy sector. The COVID19 crisis calls for a coordinated food response. Drawing on our research we recommend a cross-government committee to coordinate work on food policy. We also provide the following more specific recommendations: a. Address financial (in)security: For populations experiencing financial insecurity, it is close to impossible for the purchasing or consumption of healthy foods to be a priority. Actions include: •Reconsider the Universal Credit system so that it does not leave people with less money or with gaps in payment • Address challenges related to insecure work, such as zero hours contracts • Raise the minimum wage to a living wage. • Increase the eligibility and amount of Healthy Start vouchers and link them to local agriculture and food production. • Expand Free School Meals vouchers, and enable wider redeemability (in local food systems beyond supermarkets).• Provide funding and support for the expansion of local school meals to combat wider community food insecurity. b. Ensure food availability, and increase community resources to access to food, during and post lockdown. Without wider community and policy support the UK food system will be slow to recover. Actions include: • Support and subsidise the hospitality and food service sector to allow it to rebuild (supporting UK agriculture in the process).• Support UK farming, fishing and food production with proactive policies to stabilize labour and farm incomes • Invest in social spaces and organisations that can provide social outlets for children and families during and post lockdown (that also don’t rely on High Fat, Sugar and Salt foods (HFSS) as their main attraction). • Provide access to affordable, healthy and safe food through both the supermarket and alternative food systems – beyond food aid. c. Advertising and communication around food needs to be rethought in the UK post lockdown. Actions include: • A wider dedicated information and advertising campaign communicating a systems approach to food. This would help to educate on topics including: healthy and sustainable diets; risk and transparency of food governance; misinformation about diet on social media (e.g. miracle cures for COVID-19 or misleading claims about particular foods/diets) and finally, • A comprehensive restriction of all forms of marketing and promotion of HFSS foods.. D. Learn from international lessons that can be integrated into UK policy. • Cities and national governments have launched services to allow citizens to get basic food items directly from small scale farmers, supporting local production and providing access to healthy and fresh food. •Provided social safety nets and economic stimulus directly to vulnerable households so that they are able to purchase food despite the economic havoc wrought by Covid 19 lockdowns •Appoint a cross-government committee to coordinate work on food policy; in NYC this is being led by a “COVID-19 Food Czar”. • Understand that “Food Security is Economic Security is Economic Stimulus
Distinct regulation of dopamine D2S and D2L autoreceptor signaling by calcium
D2 autoreceptors regulate dopamine release throughout the brain. Two isoforms of the D2 receptor, D2S and D2L, are expressed in midbrain dopamine neurons. Differential roles of these isoforms as autoreceptors are poorly understood. By virally expressing the isoforms in dopamine neurons of D2 receptor knockout mice, this study assessed the calcium-dependence and drug-induced plasticity of D2S and D2L receptor-dependent G protein-coupled inwardly rectifying potassium (GIRK) currents. The results reveal that D2S, but not D2L receptors, exhibited calcium-dependent desensitization similar to that exhibited by endogenous autoreceptors. Two pathways of calcium signaling that regulated D2 autoreceptor-dependent GIRK signaling were identified, which distinctly affected desensitization and the magnitude of D2S and D2L receptor-dependent GIRK currents. Previous in vivo cocaine exposure removed calcium-dependent D2 autoreceptor desensitization in wild type, but not D2S-only mice. Thus, expression of D2S as the exclusive autoreceptor was insufficient for cocaine-induced plasticity, implying a functional role for the co-expression of D2S and D2L autoreceptors
The role of interspecific variability and herbicide pre-adaptation in the cinmethylin response of Alopecurus myosuroides
BACKGROUND: Cinmethylin is an inhibitor of plant fatty acid biosynthesis, with in-plant activity caused by its binding to fatty acid thioesterases (FAT). The recent registration of cinmethylin for pre-emergence herbicidal use in the UK represents a new mode of action (MOA) for control of the grassweed blackgrass (Alopecurus myosuroides). To date there is little published information on the extent of blackgrass’ inter-population variability in sensitivity to cinmethylin, nor on any potential effect of existing non-target-site resistance (NTSR) mechanisms on cinmethylin efficacy.
RESULTS: Here we present a study of variability in cinmethylin sensitivity amongst 97 UK blackgrass populations. We demonstrate that under controlled conditions, a UK field-rate dose of 500 g ha-1 provides effective control of the tested populations. Nevertheless, we reveal significant inter-population variability at doses below this rate, with populations previously characterised as strongly NTSR displaying the lowest sensitivity to cinmethylin. Assessment of paired resistant “R” and sensitive “S” lines from standardised genetic backgrounds confirms that selection for NTSR to the acetyl-CoA-carboxylase inhibitor fenoxaprop, and the microtubule assembly inhibitor pendimethalin, simultaneously results in reduced sensitivity to cinmethylin at doses below 500 g ha-1. Whilst we find no resistance to the field-rate dose, we reveal that cinmethylin sensitivity can be further reduced through experimental selection with cinmethylin.
CONCLUSION: Cinmethylin therefore represents a much-needed further MOA for blackgrass control, but needs to be carefully managed within a resistance monitoring and integrated weed management (IWM) framework to maximise the effective longevity of this compound
Threshold Concepts, Action Poetry and the Health Professions: An Interview with Ray Land
Note: Hilary Neve and Linda Martindale, members of the editorial team for this special Issue of the International Journal of Practice-based Learning in Health and Social Care, undertook this interview with Ray Land in June 2018. The interview was transcribed verbatim and subsequently edited for publication. In this, Ray Land considers the impact of threshold concepts generally as well as key implications for the healthcare education and practice
Distinct sites of opiate reward and aversion within the midbrain identified using a herpes simplex virus vector expressing GluR1
Repeated administration of morphine increases expression of GluR1 (an AMPA glutamate receptor subunit) in the ventral tegmental area (VTA) of the midbrain, an important neural substrate for the rewarding actions of morphine. Microinjections of a herpes simplex virus (HSV) vector that causes local overexpression of GluR1 (HSV-GluR1) into the VTA can enhance the ability of morphine to establish conditioned place preferences, suggesting that altered GluR1 expression in this region is directly associated with changes in the rewarding efficacy of morphine. We now report that in rats given HSV-GluR1 directly into the VTA, morphine is most rewarding when maximal transgene expression is in the rostral VTA, whereas morphine is aversive when maximal transgene expression is in the caudal VTA. Dual-labeling immunohistochemistry shows that this difference cannot be explained by a different fraction of dopaminergic neurons infected in the rostral versus caudal VTA. No such anatomical specificity is seen in rats given VTA microinjections of HSV-LacZ, a vector expressing a control protein (beta-galactosidase). These results suggest that distinct substrates within the VTA itself differentially contribute to the rewarding and aversive properties of opiates
Continuous synthesis of Zn2Al-CO3 layered double hydroxides: A comparison of bench, pilot and industrial scale syntheses
© 2019 The Royal Society of Chemistry. Zn2Al-CO3 was produced continuously at bench (g h-1), pilot (100s g h-1) and industrial scale (10s kg h-1). Crystal domain length and BET surface area were similar at all three scales although there was a small increase at pilot scale. Platelet size increased from 120 nm at bench to 177 nm and 165 nm at pilot scale and industrial scale, respectively. Overall this paper shows that the increase in scale by almost 2000× does not impact on the overall product quality which is an excellent indicator that continuous hydrothermal synthesis is a route for nanomaterials synthesis
Modeling the sustainability and economics of stacked herbicide-tolerant traits and early weed management strategy for waterhemp (Amaranthus tuberculatus) control
Diversity is key for sustainable weed management and can be achieved via both chemical and nonchemical control tactics. Genetically modified crops with two-way or three-way stacked herbicide-tolerant traits allow use of herbicide mixtures that would otherwise be phytotoxic to the crop. Early weed management(EWM)strategies promote the use of PRE herbicides with residual activity to keep the field free of weeds early in the season for successful crop establishment. To evaluate the respective sustainability and practicality of the two chemical-based management tactics(i.e.,stacked traits and EWM),we used a population model of waterhemp, Amaranthus tuberculatus (Moq.) Sauer (syn. rudis), to simulate the evolution of resistance in this key weed species in midwestern U.S.soybean [Glycinemax(L.)Merr.] agroecosystems. The model tested scenarios with a varying number of herbicide sites of action (SOAs), application timings (PRE and POST), and preexisting levels of resistance. Results showed that both tactics provided opportunity for controlling resistant A.tuberculatus populations. In general,each pass over the field should include at least two effective herbicide SOAs. Nevertheless, the potential evolution of cross-resistance may void the weed control programs embraced by stacked traits and diverse herbicide SOAs. Economic calculations suggested that the diversified programs could double long-term profitability when compared to the conventional system, because of improved yield and grain quality. Ultimately, the essence of a sustainable herbicide resistance management strategy is to be proactive. Although a herbicide-dominated approach to diversifying weed management has been prevalent, the increasing presence of weed populations with multiple resistance means that finding herbicides to which weed populations are still susceptible is becoming increasingly difficult, and thus the importance of reintroducing cultural and mechanical practices to support herbicides must be recognized
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