2,376 research outputs found
THE INCREASING ROLE OF AGRIBUSINESS IN AGRICULTURAL ECONOMICS
While the demand for traditional agricultural economics is diminishing, there is a growing need for the economics and management of the food sector and the environment. Departments of agricultural economics have shown great flexibility in including agribusiness in their Bachelor's and Master's teaching programs. Ph.D and research programs appear to adjust more slowly to changing demand. Although agricultural economics programs are providing a variety of service course offerings, opportunities for joint programs with biological, physical, and natural sciences, particularly resource management, are not being exploited. If business schools decide to compete for agribusiness students in the future, missed opportunities with other departments and schools may become very costly. If this profession is to remain viable in the long run, it must continue to evolve, developing opportunities with biological, physical, and natural disciplines, in order to meet the demands of a changing market.agribusiness, agricultural economics, education, extension, research, Agribusiness, Teaching/Communication/Extension/Profession,
Antiferromagnetic phase of the gapless semiconductor V3Al
Discovering new antiferromagnetic compounds is at the forefront of developing
future spintronic devices without fringing magnetic fields. The
antiferromagnetic gapless semiconducting D03 phase of V3Al was successfully
synthesized via arc-melting and annealing. The antiferromagnetic properties
were established through synchrotron measurements of the atom-specific magnetic
moments, where the magnetic dichroism reveals large and oppositely-oriented
moments on individual V atoms. Density functional theory calculations confirmed
the stability of a type G antiferromagnetism involving only two-third of the V
atoms, while the remaining V atoms are nonmagnetic. Magnetization, x-ray
diffraction and transport measurements also support the antiferromagnetism.
This archetypal gapless semiconductor may be considered as a cornerstone for
future spintronic devices containing antiferromagnetic elements.Comment: Accepted to Physics Review B on 02/23/1
Prediction of Ferromagnetic Ground State of NaCl-type FeN
Ab-initio results for structural and electronic properties of NaCl-type FeN
are presented in a framework of plane-wave and ultrasoft pseudopotentials.
Competition among different magnetic ordering is examined. We find the
ferromagnetic phase stable overall. Stabilization over the unpolarized phase is
obtained by splitting one flat t_2g-type band crossing the Fermi energy. A
comparison with CrN is considered. We find large differences in the properties
of the two systems that can be addressed to the smaller ionicity and
magnetization of FeN.Comment: 5 pages, 4 figures, twocolumn latex style Sentence changed in Section
III line 1
A composition theorem for the Fourier Entropy-Influence conjecture
The Fourier Entropy-Influence (FEI) conjecture of Friedgut and Kalai [FK96]
seeks to relate two fundamental measures of Boolean function complexity: it
states that holds for every Boolean function , where
denotes the spectral entropy of , is its total influence,
and is a universal constant. Despite significant interest in the
conjecture it has only been shown to hold for a few classes of Boolean
functions.
Our main result is a composition theorem for the FEI conjecture. We show that
if are functions over disjoint sets of variables satisfying the
conjecture, and if the Fourier transform of taken with respect to the
product distribution with biases satisfies the conjecture,
then their composition satisfies the conjecture. As
an application we show that the FEI conjecture holds for read-once formulas
over arbitrary gates of bounded arity, extending a recent result [OWZ11] which
proved it for read-once decision trees. Our techniques also yield an explicit
function with the largest known ratio of between and
, improving on the previous lower bound of 4.615
Time resolved observation of resonant and non-resonant contributions to the nonlinear susceptibility χ(3)
The resonant and nonresonant part of χ(3) are distinguished by their different time behavior. The medium is coherently excited by two picosecond light pulses of defined frequency difference and the state of the system is monitored by a third properly delayed probe pulse. Results are presented on neat liquids of carbontetrachloride and cyclohexane and on the mixture of CCl4: C6H12
High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator
The discovery of the quantum Hall (QH) effect led to the realization of a
topological electronic state with dissipationless currents circulating in one
direction along the edge of a two dimensional electron layer under a strong
magnetic field. The quantum anomalous Hall (QAH) effect shares a similar
physical phenomenon as the QH effect, whereas its physical origin relies on the
intrinsic spin-orbit coupling and ferromagnetism.Here we report the
experimental observation of the QAH state in V-doped (Bi,Sb)2Te3 films with the
zero-field longitudinal resistance down to 0.00013+-0.00007h/e2 (~3.35+-1.76
ohm), Hall conductance reaching 0.9998+-0.0006e2/h and the Hall angle becoming
as high as 89.993+-0.004degree at T=25mK. Further advantage of this system
comes from the fact that it is a hard ferromagnet with a large coercive field
(Hc>1.0T) and a relative high Curie temperature. This realization of robust QAH
state in hard FMTIs is a major step towards dissipationless electronic
applications without external fields.Comment: 16 pages, 4 figures, this is the final version, accepted by Nature
Materials, forthcomin
Functional Evaluations of Genes Disrupted in Patients with Tourette’s Disorder
Tourette’s disorder (TD) is a highly heritable neurodevelopmental disorder with complex genetic architecture and unclear neuropathology. Disruptions of particular genes have been identified in subsets of TD patients. However, none of the findings have been replicated, probably due to the complex and heterogeneous genetic architecture of TD that involves both common and rare variants. To understand the etiology of TD, functional analyses are required to characterize the molecular and cellular consequences caused by mutations in candidate genes. Such molecular and cellular alterations may converge into common biological pathways underlying the heterogeneous genetic etiology of TD patients. Herein, we review specific genes implicated in TD etiology, discuss the functions of these genes in the mammalian central nervous system and the corresponding behavioral anomalies exhibited in animal models, and importantly, review functional analyses that can be performed to evaluate the role(s) that the genetic disruptions might play in TD. Specifically, the functional assays include novel cell culture systems, genome editing techniques, bioinformatics approaches, transcriptomic analyses, and genetically modified animal models applied or developed to study genes associated with TD or with other neurodevelopmental and neuropsychiatric disorders. By describing methods used to study diseases with genetic architecture similar to TD, we hope to develop a systematic framework for investigating the etiology of TD and related disorders
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