Price risk exposure of Australian Merinos - is it in the bloodline?

Sheep producers and their advisors utilise Australian Merino bloodline trial data to guide future sheep breeding objectives and ram selection. To adequately assess the economic outcomes from different bloodlines in the decision making process, there is a need to consider the impact of wool and sheep meat price risk. Using a steady-state wether flock model that accounts for the lifetime productivity of 268 reported Merino bloodlines and stochastic dependency in weekly wool and sheep meat prices from 28 June 2005 to 10 November 2011, gross incomes per dry sheep equivalent (GI/DSE) were calculated for a weekly time step. The analysis found that across all bloodlines and market price scenarios, GI/DSE ranged between AU$13.92 and AU$67.83, with an overall mean of AU$32.60. The individual means of bloodlines across the time series ranged from AU$37.46 to AU$25.19 GI/DSE. The coefficient of variation, used as the measure of relative risk for each bloodline, ranged from 0.24 to 0.30 with a mean of 0.25. The analysis showed that a bloodlines exposure to price risk has a curvilinear relationship to fibre diameter and fleece weight. The results from a risk-reward point of view indicate that the majority of Australian Merino bloodlines are risk-inefficient. This suggests Australian sheep producers have a significant opportunity to increase net returns and reduce price risk exposure by identifying and switching to more risk-efficient bloodlines

The life cycle of starbursting circumnuclear gas discs

High-resolution observations from the sub-mm to the optical wavelength regime resolve the central few 100pc region of nearby galaxies in great detail. They reveal a large diversity of features: thick gas and stellar discs, nuclear starbursts, in- and outflows, central activity, jet interaction, etc. Concentrating on the role circumnuclear discs play in the life cycles of galactic nuclei, we employ 3D adaptive mesh refinement hydrodynamical simulations with the RAMSES code to self-consistently trace the evolution from a quasi-stable gas disc, undergoing gravitational (Toomre) instability, the formation of clumps and stars and the disc's subsequent, partial dispersal via stellar feedback. Our approach builds upon the observational finding that many nearby Seyfert galaxies have undergone intense nuclear starbursts in their recent past and in many nearby sources star formation is concentrated in a handful of clumps on a few 100pc distant from the galactic centre. We show that such observations can be understood as the result of gravitational instabilities in dense circumnuclear discs. By comparing these simulations to available integral field unit observations of a sample of nearby galactic nuclei, we find consistent gas and stellar masses, kinematics, star formation and outflow properties. Important ingredients in the simulations are the self-consistent treatment of star formation and the dynamical evolution of the stellar distribution as well as the modelling of a delay time distribution for the supernova feedback. The knowledge of the resulting simulated density structure and kinematics on pc scale is vital for understanding inflow and feedback processes towards galactic scales.Comment: accepted by MNRA

Preventing young farmers from leaving the farm: investigating the effectiveness of the young farmer payment using a behavioural approach

The number of young farmers has decreased over recent decades in several developed countries such as the United States and European countries. A recent strategy adopted by the European Union to address the resulting age imbalance is the Young Farmer Payment which provides an additional payment on top of the average basic payment introduced in the last Common Agricultural Policy reform. The objective of this study is to determine, by means of a behavioural approach, how this payment in fl uenced the incentives of young farmers to stay in the farm. Using the endogenous succession cycle model and the structural modelling technique, we found that the payment a ff ected young farmers ’ willingness to stay through its in fl uence on non-economic motivational goals. However, we also found that there are other factors that can be even more in fl uential, such as pessimism about farming, community and family integration, participation in decision making, and the opinion of neighbours, among others. Based on the results, we argue that similar policies could be adopted in other countries, although policies would be more e ff ective in addressing age imbalances if they are accompanied with complementary strategies aimed to deal with the identi fi ed social and psychological considerations

Transparency of a geographically distributed test platform for fuel cell electric vehicle powertrain systems based on x-in-the-loop approach

X-in-the-loop is a new vehicle development and validation method for increasingly complex vehicle systems, which integrates the driver and the environment. In view of recent developments in fuel cell electric vehicle powertrain systems, Tongji University and Karlsruhe Institute of Technology have jointly developed a set of distributed test platforms based on the X-in-the-loop approach. This platform contains models and test equipment for a fuel cell electric vehicle powertrain system. Due to the involvement of remote connection and the Internet, test with connected test benches will suffer great uncertainty cause of signal transfer delay. To figure out this uncertainty, the concept of transparency is introduced. Four parameters were selected as transparency parameters in this distributed test platform. These include vehicle speed, fuel cell output power, battery output power, and electric motor torque under several different configuration settings. With the help of transparency theory and statistical methodology, especially Analysis of Variance (ANOVA), the transparency of these four parameters was established, vehicle speed, electric motor torque, battery power, and fuel cell power are affected by network state, the degree of influence is enhanced in turn. Using new defined parametric and non-parametric methods, this paper identifies the statistical significance and the transparency limitations caused by Internet under these several configurations. These methods will generate inputs for developer setting the distributed test configuration. These results will contribute to optimize the process of geographically distributed validation and joint development

Analysis of agribusiness value chains servicing small-holder dairy farming communities in Punjab, Pakistan: three case studies

The agriculture sector in Pakistan, as in most developing countries, is dominated by smallholder producers. Pakistan has the world’s third largest dairy industry, and milk is efficiently collected and distributed chiefly by informal value chains that market the raw product with minimal cool chain infrastructure. Formal processors have a small market share of 5%. Interview data from farmers, milk collectors and consumers from three rural-urban case study value chains were analysed to study opportunities and challenges faced by the dairy industry. Compositional analysis of milk samples (n=84) collected along these chains identified the fact that in Pakistan informal milk chains provide a cheaper source of calories for the final consumer than industrialised milk chains (USD 0.12 compared USD 0.15 per 100 calories). These three chains created an estimated 4,872 jobs from farm to market and provided access to interest-free credit for the farmers. The existing government price setting mechanism at the retail end and collusion by large processors to set farm gate prices provided significant limitations to the profitability of small-holder farms providing the product. The absence of quality and quantity standards, amid the exchange of huge numbers of small volumes of milk along these chains, are major impediments to industry growth

Dairying and whole-farm economics of crop-livestock farming systems - comparing arid and irrigated districts of Punjab, Pakistan

Dairying is an important component of Pakistan’s mixed crop-livestock farming systems. The national economy engages some 8.8 million small-scale producer households. The country produces more milk than any other except for the United States and India. Yet little is known about small-scale producer microeconomics to inform policy development for improving their welfare. In this paper we aim to identify the whole farm profitability of small agricultural households, with a specific focus on milk production. We compare two contrasting agro-ecological regions within Pakistan’s Punjab (irrigated Okara and rain-fed Bhakkar) using results for a single 2008-09 fiscal year of production for 212 farms. Net farm profits, taking long-run opportunity costs of labour and capital into account, showed only 10 per cent of these farms to be profitable in either district, though short-run profits, accounting for cash costs only, showed positive whole farm gross margins for 90 per cent and 80 per cent of farms in Okara and Bhakkar, respectively. The returns on assets (at 2.78 per cent and 0.53 per cent for the two districts) was lower than the national average return on savings (9 per cent). For dairy enterprises, total costs were higher than incomes; so many farms (70 per cent and 60 per cent, respectively) were assessed as making losses. Given the low opportunity costs of feeds (often crop residues) and of labour (6.2 per cent unemployment) and the high rate of inflation (11.8 per cent), returns on factors of production including labour and capital, may not be lower than international standards. There is a need, however, to raise the dairy industry’s overall productivity to make dairying viable; and to identify an optimal land and livestock combination that is profitable and commercially viable

Simulating the population dynamics of barley grass (Hordeum spp.) and impacts of weed management strategies in a southern Australian lucerne (Medicago sativa) pasture

Context: Barley grass (Hordeum spp. L.) is an annual, invasive grass weed of southern Australian crops and pastures, frequently associated with weight loss and carcass damage in sheep due to its sharp seeds. Knowledge gaps exist regarding optimal density thresholds for effective control to reduce impacts on animal production. The value of integrated weed management (IWM) over individual control options for reducing barley grass populations in pasture is also unknown. Aims: We aimed to develop a model for simulating the population dynamics of barley grass within lucerne (Medicago sativa L.) pastures of southern Australia and to test the hypothesis that combining herbicides with mowing will be more effective for removing barley grass seedbanks over time than individual control measures. Methods: The model was developed within Microsoft Excel and adapted from other annual grass models. The model takes a Monte Carlo approach to simulate control impacts on weed seedbanks over 10 years using five weed-control density thresholds. It was parameterised using data from recent experiments and available literature. Key results: The most effective long-term control strategy for barley grass occurred with a density threshold of 5 seedlings m−2 by combining early and late herbicide applications, and by combining early and late herbicides with mowing, reducing the seedbank by 86% and 89%, respectively. Conclusions: Simulation results showed that IWM programs were more effective than individual control options in reducing the barley grass seedbanks over 10 years, particularly at low weed densities (≤50 seedlings m−2). Implications: Incorporation of this model into a bioeconomic grazing systems model will be valuable for determining the economic impacts and optimal weed-control strategies for minimising the effects of barley grass seed contamination in lamb production systems

One-step microwave synthesis of palladium-carbon nanotubes hybrids with improved catalytic performance

7 páginas, 7 figuras, 3 tablas.-- El pdf del artículo es la versión pre-print.A fast and easy one-step linker-free approach for the synthesis of palladium nanoparticle/multiwall carbon nanotube (Pd-NP/MWCNT)hybrid materials is described using microwave irradiation for the effective decomposition of Pd2dba3 complex in the presence of MWCNTs. High loadings of Pd nanoparticles (up to 40 wt.%) having sizes between 3 and 5 nm are deposited on the surface of MWCNTs within a time of only 2 minutess. The Pd-NP/MWCNT materials serve as efficient catalysts in C-C coupling as well as in hydrogenation reactions, all characterized by high conversion rates using a small amount of catalysts, high turnover frequency values and good recyclbility.Financial support from the Spanish Ministerio de Ciencia e Innovación (MICINN) and the European Regional Development Fund (ERDF) under projects CTQ2008-01784 and MAT2007-66927-C02-01, and the Gobierno de Aragón (DGAPI086- 08) is gratefully acknowledged. M.C. thanks MICINN for her Grant No. BES-2008-003503.Peer reviewe