First-Principles Studies of Local Order in Relaxor Ferroelectrics

A key to optimizing the growth of the new single-crystal relaxor ferroelectrics is resolving basic questions concerning their structural properties and energetics. We report on initial first-principles total energy and force calculations, examining the energetics of local order in PZN type relaxors.Comment: 9 pages, LaTeX (aipproc), three eps figure

AGRICULTURE'S STAKE IN RURAL ECONOMIC DEVELOPMENT

Community/Rural/Urban Development,

SOUTHERN FARMS AND RURAL COMMUNITIES: DEVELOPING DIRECTIONS FOR ECONOMIC DEVELOPMENT RESEARCH AND POLICY

Community/Rural/Urban Development,

CIVIC COMMUNITY APPROACHES TO RURAL DEVELOPMENT IN THE SOUTH: DISCUSSION

Community/Rural/Urban Development,

THE IMPACT OF NATURAL GAS PRICE DEREGULATION ON THE SOUTH CAROLINA FOOD PROCESSING SECTORS

Resource /Energy Economics and Policy,

Where have all the packing plants gone? : the new meat geography in rural America

The meat industry is an economic powerhouse for rural America---accounting for roughly one of every 16 rural manufacturing jobs. Moreover, this rural powerhouse is adding jobs at a fast clip, with recent growth of 8.5 percent a year versus just 1.2 percent a year for all rural manufacturing industries. Finally, rural America has captured a commanding 52 percent of all meat industry jobs, far above the level of a decade ago.> While all these figures are welcome news to rural areas eager to expand employment, geographic shifts under way in the industry raise fresh doubts over which rural communities will land new meat plants. Once concentrated in midwestern urban centers like Chicago, the meat industry is now most often found in rural towns and hamlets---and often far from the Midwest. Poultry-processing has moved to the Southeast. Beef packing plants have moved to the Great Plains. And pork packing plants have begun moving out of the Corn Belt to the Southeast and Great Plains, but where they go next is highly uncertain, with the future location of hog production itself very much in question.> What geographic shifts lie ahead for the meat-processing industry? And what do the shifts in this powerhouse industry mean for the future of the rural economy? Drabenstott, Henry, and Mitchell review some critical trends in the meat industry by examining for the first time a special database on the industry, the Longitudinal Research Database (LRD) maintained by the Bureau of the Census. They conclude that the meat industry is likely to concentrate geographically even more in the future, promising a new source of economic growth for some rural communities while leaving many others behind. Yet even in areas where the industry does locate, a sharp drop in industry wages raises new questions about its local economic impact.Meat industry and trade ; Rural development

New security notions and feasibility results for authentication of quantum data

We give a new class of security definitions for authentication in the quantum setting. These definitions capture and strengthen existing definitions of security against quantum adversaries for both classical message authentication codes (MACs) and well as full quantum state authentication schemes. The main feature of our definitions is that they precisely characterize the effective behavior of any adversary when the authentication protocol accepts, including correlations with the key. Our definitions readily yield a host of desirable properties and interesting consequences; for example, our security definition for full quantum state authentication implies that the entire secret key can be re-used if the authentication protocol succeeds. Next, we present several protocols satisfying our security definitions. We show that the classical Wegman-Carter authentication scheme with 3-universal hashing is secure against superposition attacks, as well as adversaries with quantum side information. We then present conceptually simple constructions of full quantum state authentication. Finally, we prove a lifting theorem which shows that, as long as a protocol can securely authenticate the maximally entangled state, it can securely authenticate any state, even those that are entangled with the adversary. Thus, this shows that protocols satisfying a fairly weak form of authentication security automatically satisfy a stronger notion of security (in particular, the definition of Dupuis, et al (2012)).Comment: 50 pages, QCrypt 2016 - 6th International Conference on Quantum Cryptography, added a new lifting theorem that shows equivalence between a weak form of authentication security and a stronger notion that considers side informatio

THE IMPACT OF NEW INDUSTRY ON COUNTY GOVERNMENT PROPERTY TAX REVENUE

Public Economics,

Lyman Break Galaxies in the NGST Era

With SIRTF and NGST in the offing, it is interesting to examine what the stellar populations of z~3 galaxies models imply for the existence and nature of Lyman-break galaxies at higher redshift. To this end, we ``turn back the clock'' on the stellar population models that have been fit to optical and infrared data of Lyman-break galaxies at z~3. The generally young ages (typically 10^8 +- 0.5 yr) of these galaxies imply that their stars were not present much beyond z=4. For smooth star-formation histories SFR(t) and Salpeter IMFs, the ionizing radiation from early star-formation in these galaxies would be insufficient to reionize the intergalactic medium at z~6, and the luminosity density at z~4 would be significantly lower than observed. We examine possible ways to increase the global star-formation rate at higher redshift without violating the stellar-population constraints at z~3.Comment: To appear in "The Mass of Galaxies at Low and High Redshift", ed. R. Bender and A. Renzini, ESO Astrophysics Symposia, Springer-Verlag 7 Pages, 2 figure