Efficiency of Scottish Farms: A Stochastic Cost Frontier Analysis

In this paper the relative cost efficiency of Scottish farms is determined, and variables that explain this efficiency by farm type are identified and implications discussed. A panel dataset from the Farm Accounts Scheme (FAS) survey for the period 1997-2004 was used for the estimation. A cost efficiency indicator was measured using a fixed effect panel data regression. Further analysis, to explain the efficiency results, indicated the presence of important farm size and regional effects. However, other variables, whilst statistically significant, did not produce a consistent effect across the different farm types.Stochastic cost frontier analysis, cost efficiency, Scottish farms, Common Agricultural Policy, Farm Management, Q12,

Explaining Cost Efficiency of Scottish Farms: A Stochastic Frontier Analysis

In this paper the cost efficiency of Scottish farms is determined, variables that explain the relative cost efficiency by farm type are identified and implications discussed. A cost efficiency approach was selected as it can deal with farms producing multiple outputs (in contrast to production frontiers), and second because it can accommodate output constraints imposed by the Common Agricultural Policy (CAP). To estimate the stochastic cost frontier, a generalised multi-product translog cost function was estimated for five farm types: dairy, cereals and general cropping, cattle and sheep, specialist sheep and mixed farms. Eight farm outputs and four inputs were considered. The data for the estimation were drawn from the Farm Accounts Scheme (FAS) survey for the period 1997-2004, which allowed the construction of an unbalanced panel dataset for 358 farms. Cost efficiency was measured as a fixed effect term and this was used to construct an indicator of relative cost efficiency by farm type. Further analysis, to explain the efficiency results, indicated the presence of important farm size and regional effects. However, other variables used in the analysis, whilst statistically significant, did not produce a consistent effect across the different farm types.Stochastic cost frontier analysis, cost efficiency, Scottish farms, Common Agricultural Policy., Productivity Analysis, Farm Management,

Certain subclasses of multivalent functions defined by new multiplier transformations

In the present paper the new multiplier transformations \mathrm{{\mathcal{J}% }}_{p}^{\delta }(\lambda ,\mu ,l) (\delta ,l\geq 0,\;\lambda \geq \mu \geq 0;\;p\in \mathrm{% }%\mathbb{N} )} of multivalent functions is defined. Making use of the operator $\mathrm{{\mathcal{J}}}_{p}^{\delta }(\lambda ,\mu ,l),$ two new subclasses $\mathcal{P}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ and $\widetilde{\mathcal{P}}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$\textbf{\ }of multivalent analytic functions are introduced and investigated in the open unit disk. Some interesting relations and characteristics such as inclusion relationships, neighborhoods, partial sums, some applications of fractional calculus and quasi-convolution properties of functions belonging to each of these subclasses $\mathcal{P}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ and $\widetilde{\mathcal{P}}_{\lambda ,\mu ,l}^{\delta }(A,B;\sigma ,p)$ are investigated. Relevant connections of the definitions and results presented in this paper with those obtained in several earlier works on the subject are also pointed out

The effect of external grit particle size on friction coefficients and grit embedment of brake friction material

Changes in friction and contact surfaces characteristics of a brake friction material during drag and stop mode test were investigated using a brake model tribo-tester. Scanning Electron Microscopy (SEM) was utilized to reveal the surface topography characteristics and analyze the external particle size effects on friction coefficients and grit embedment. Silica sand with three different particle sizes of 50-180 µm, 180-355 µm and 355-500 µm was used in this work. At higher disc sliding speed, results showed that small grit particles cause higher friction due to greater frequency of particles mixing and modifying the effective contact compared to bigger particles. Good friction stability was attributed to smaller particles size providing more stable contact by actively involved in building up and reducing the rate of changes of the effective contact area. Through SEM analysis, signs of formation and disintegration of contact plateaus correlated well with particle size and hence, suggesting the significant role of particle size as wearing mechanism. Grit embedment (GE) was greatly dependent on presence of compacted wear debris as most particles were found embedded into compacted wear debris. Total GE of 2.7% was observed for silica sand of 50-180 µm, 4.5% for 180-355 µm and 3.0% for 355-500 µm

Z decays into light gluinos: a calculation based on unitarity

The Z boson can decay to a pair of light gluinos through loop-mediated processes. Based on unitarity of the S-matrix, the imaginary part of the decay amplitude is computed in the presence of a light bottom squark. This imaginary part can provide useful information on the full amplitude. Implications are discussed for a recently proposed light gluino and light bottom squark scenario.Comment: 19 pages, LaTeX, 3 figures, submitted to Phys. Rev.

Characterization of Molecular Determinants of the Conformational Stability of Macrophage Migration Inhibitory Factor: Leucine 46 Hydrophobic Pocket

Macrophage Migration Inhibitory Factor (MIF) is a key mediator of inflammatory responses and innate immunity and has been implicated in the pathogenesis of several inflammatory and autoimmune diseases. The oligomerization of MIF, more specifically trimer formation, is essential for its keto-enol tautomerase activity and probably mediates several of its interactions and biological activities, including its binding to its receptor CD74 and activation of certain signaling pathways. Therefore, understanding the molecular factors governing the oligomerization of MIF and the role of quaternary structure in modulating its structural stability and multifunctional properties is crucial for understanding the function of MIF in health and disease. Herein, we describe highly conserved intersubunit interactions involving the hydrophobic packing of the side chain of Leu46 onto the β-strand β3 of one monomer within a hydrophobic pocket from the adjacent monomer constituted by residues Arg11, Val14, Phe18, Leu19, Val39, His40, Val41, Val42, and Pro43. To elucidate the structural significance of these intersubunit interactions and their relative contribution to MIF’s trimerization, structural stability and catalytic activity, we generated three point mutations where Leu46 was replaced by glycine (L46G), alanine (L46A) and phenylalanine (L46F), and their structural properties, stability, oligomerization state, and catalytic activity were characterized using a battery of biophysical methods and X-ray crystallography. Our findings provide new insights into the role of the Leu46 hydrophobic pocket in stabilizing the conformational state of MIF in solution. Disrupting the Leu46 hydrophobic interaction perturbs the secondary and tertiary structure of the protein but has no effect on its oligomerization state

Integral effect non-loca test results for the integral type reactor SMART-P using the VISTA facility

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.The SMART-P a pilot plant of the integral type reactor SMART(System Integrated Modular Advanced Reactor) which has new innovative design features aimed at achieving a highly enhanced safety and improved economics. A test facility (VISTA) has been constructed to simulate the SMART-P which is a full height and 1/96 volume scaled test facility with respect to the SMART-P. The VISTA facility has been used to understand the thermal-hydraulic behavior including several operational transients and design basis accidents and finally it will contribute to verifying the system design of the SMART-P. During the past five years, several integral effect tests have been carried out and reported, including performance tests, MCP(Main Coolant Pump) transients, power transients and heatup or cooldown procedures. In the present study, the VISTA facility was subjected to the major safety related non-LOCA transient conditions in a primary and secondary system, including a power increase due to a CEDM (Control Element Drive Mechanism) withdrawal, a feedwater decrease and a steam flow increase in order to verify the safety analysis code for the SMART-P.cs201

Dyonic Non-Abelian Black Holes

We study static spherically symmetric dyonic black holes in Einstein-Yang-Mills-Higgs theory. As for the magnetic non-abelian black holes, the domain of existence of the dyonic non-abelian black holes is limited with respect to the horizon radius and the dimensionless coupling constant $\alpha$, which is proportional to the ratio of vector meson mass and Planck mass. At a certain critical value of this coupling constant, $\hat \alpha$, the maximal horizon radius is attained. We derive analytically a relation between $\hat \alpha$ and the charge of the black hole solutions and confirm this relation numerically. Besides the fundamental dyonic non-abelian black holes, we study radially excited dyonic non-abelian black holes and globally regular gravitating dyons.Comment: LaTeX, 22 pages, 16 figures, three figures added, file manipulation error in previous replac

CP asymmetries in penguin-induced B decays in general left-right models

We study CP asymmetries in penguin-induced b -> s\bar{s}s decays in general left-right models without imposing manifest or pseudomanifest left-right symmetry. Using the effective Hamiltonian approach, we evaluate CP asymmetries in B^\pm -> \phi K^{(\ast)\pm} decays as well as mixing induced B meson decays B -> J/\psi K_s and B -> \phi K_s decays. Based on recent measurements revealing large CP violation, we show that nonmanifest type model is more favored than manifest or pseudomanifest type.Comment: 16 pages, 12 eps figure

Toward a predictive understanding of earth’s microbiomes to address 21st century challenges

Microorganisms have shaped our planet and its inhabitants for over 3.5 billion years. Humankind has had a profound influence on the biosphere, manifested as global climate and land use changes, and extensive urbanization in response to a growing population. The challenges we face to supply food, energy, and clean water while maintaining and improving the health of our population and ecosystems are significant. Given the extensive influence of microorganisms across our biosphere, we propose that a coordinated, cross-disciplinary effort is required to understand, predict, and harness microbiome function. From the parallelization of gene function testing to precision manipulation of genes, communities, and model ecosystems and development of novel analytical and simulation approaches, we outline strategies to move microbiome research into an era of causality. These efforts will improve prediction of ecosystem response and enable the development of new, responsible, microbiome-based solutions to significant challenges of our time