Modelling the Gross Cost of Transporting Pig Slurry to Tillage Spread Lands in a Post Transition Arrangement within the Nitrates Directive.

working paperThe context of this paper is in the phasing out of the transitional arrangement under the Nitrates Directive. As there is relatively little grassland capable of taking significant amounts of pig slurry available in the vicinity of the main pig production areas, in this paper we attempt to quantify the cost of transporting this slurry to the nearest available tillage land. The approach taken was to examine the geographic structure underlying the pig sector in Ireland using Geographic Information Systems (GIS) technology. The study highlighted the differential cost with, amounting to 10% of gross margin on average and as high in major pig producing areas as 21.5% in Longford and 16.6% in Cavan, while lower at 7-9% in South Tipperary and Cork. Thus while the problem is significant, the impact is not constant across the country, highlighting the value of a spatial analytical approach. Future work should assess the existing cost of spreading manure in order to be able to ascertain the net cost of spreading on tillage lands. The robustness of the results also need to be tested to assess the implications of changes in the prices of fossil fuels and fertilisers, both in terms of the cost function and in terms of the cost of substitutable mineral fertilise

Differences among high, medium, and low profit dairy operations: an analysis of 2004-2008 Kansas Farm Management Association Dairy Enterprises

Dairy Research, 2009 is known as Dairy Day, 2009The financial bottom line, or net income, is a key factor in determining how successful a dairy has been historically as well as an indicator of the financial ease or struggles the dairy might have in the future. What causes net income to vary from one operation to another is a key question for dairy farmers. For example, does milk price received, feed cost, total cost, or milk production have the greatest impact on net return variability? In this study, we evaluated Kansas Farm Management Dairy Enterprise data from the past 5 years to determine correlation of revenue, production, and cost factors among groups of high, medium, and low profit dairy operations. High-profit producers had larger operations, had slightly greater total costs ($62.63 per cow), and received slightly lower milk prices ($0.56/100 lb of milk) compared with low-profit producers. In contrast, the high profit group produced significantly more milk per cow. Milk price received and cost per cow did not affect profit nearly as much as total milk produced per cow. This study was conducted with data reported by small to midsize dairy herds. Further research should examine whether these results hold true for large herds

Enabling III-V-based optoelectronics with low-cost dynamic hydride vapor phase epitaxy

Silicon is the dominant semiconductor in many semiconductor device applications for a variety of reasons, including both performance and cost. III-V materials have improved performance compared to silicon, but currently they are relegated to applications in high-value or niche markets due to the absence of a low-cost, high-quality production technique. Here we present an advance in III-V materials synthesis using hydride vapor phase epitaxy that has the potential to lower III-V semiconductor deposition costs by orders of magnitude while maintaining the requisite optoelectronic material quality that enables III-V-based technologies to outperform Si. We demonstrate the impacts of this advance by addressing the use of III-Vs in terrestrial photovoltaics, a highly cost-constrained market. The emergence of a low-cost III-V deposition technique will enable III-V electronic and opto-electronic devices, with all the benefits that they bring, to permeate throughout modern society.Comment: pre-prin

Prox-1: Automated Proximity Operations on an ESPA Class Platform

The Georgia Institute of Technology Prox-1 mission is an ESPA-class, student-designed, student-built satellite mission designed to demonstrate automated relative trajectory control in conjunction with a semi-cooperative target in Low-Earth Orbit. It is scheduled for launch in September of 2016 aboard the Department of Defense Space Test Program (STP-2) mission as a secondary payload. The primary mission of the spacecraft is to perform flight qualification and performance validation of experimental flight hardware; to deploy The Planetary Society’s LightSail mission, an internally housed 3U cubesat; and to perform relative trajectory control with respect to that target utilizing passive thermal imaging and automated on-board guidance algorithms. Several subsystems are integrated to accomplish this mission, and a description of the subsystem components is detailed in this paper. An overview of the concept operations is also presented here. For the automated proximity operations phase of the mission, Prox-1 will demonstrate an advanced Guidance, Navigation, & Control subsystem. This subsystem will combine GN&C algorithms and filters developed in-house and based on reference literature. This paper will provide an overview of the Prox-1 mission and the advancements it brings to the small satellite community

Puzzling subunits of mitochondrial cytochrome reductase

The ubiquinol-cytochrome c reductase complex, like the other proton-pumping respiratory complexes of mitochondria, is an assembly of many different subunits. However, only a few of these subunits participate directly in the electron transfer and proton translocation. The roles of the other subunits are largely unknown. We discuss here some intriguing features of two of these subunits

Applications of stable water and carbon isotopes in watershed research: Weathering, carbon cycling, and water balances

Research on rivers has traditionally involved concentration and flux measurements to better understand weathering, transport and cycling of materials from land to ocean. As a relatively new tool, stable isotope measurements complement this type of research by providing an extra label to characterize origin of the transportedmaterial, its transfer mechanisms, and natural versus anthropogenic influences. These new stable isotope techniques are scalable across a wide range of geographic and temporal scales. This review focuses on three aspects of hydrological and geochemical river research that are of prime importance to the policy issues of climate change and include utilization of stable water and carbon isotopes: (i) silicate and carbonate weathering in river basins, (ii) the riverine carbon and oxygen cycles, and (iii) water balances at the catchment scale. Most studies at watershed scales currently focus on water and carbon balances but future applications hold promise to integrate sediment fluxes and turnover, ground and surface water interactions, as well as the understanding of contaminant sources and their effects in river systems

Blocking Deprotonation with Retention of Aromaticity in a Plant ent-Copalyl Diphosphate Synthase Leads to Product Rearrangement

Biosynthesis of the labdane-related diterpenoids, a large superfamily of over 7,000 natural products, is characterized by the use of class II diterpene cyclases.[1] The vast majority of these biocatalysts are exclusively found in plants, stemming from repeated evolutionary diversification of the ent-copalyl diphosphate synthase (CPS) required for gibberellin phytohormone biosynthesis – i.e., via gene duplication and neofunctionalization.[2] As implied by this evolutionary scenario, these enzymes must exhibit catalytic plasticity that enables new products to readily arise. Consistent with this hypothesis, we have shown that substitution of smaller residues for the catalytic base group can lead to the incorporation of water, yielding hydroxylated products.[3] Here it is reported that larger aromatic replacement of the histidine from the catalytic base group leads to even more profound alteration of product outcome, rearrangement via a series of 1,2-hydride and methyl shifts. Coupled with additional mutational analysis and quantum chemical calculations, this clarifies the catalyzed reaction and underlying enzymatic structure-function relationships of the ancestral CPS