Winners and Losers: Formula versus Competitive Funding of Agricultural Research

Research and Development/Tech Change/Emerging Technologies, O3, O4, Q16,

Impacts of Economic and Psychological Factors on Women’s Obesity and Food Assistance Program Participation: Evidence from the NLSY Panel

Over the past thirty-five years, the U.S. adult obesity rate has more than doubled from roughly 15% to 35%, reflecting a general diffusion of obesity across all segments of the adult population (USDHHS). Obesity is a concern because it increases the risk for cardiovascular diseases, diabetes, and most forms of cancer, except for lung. Earlier studies of obesity of U.S. adults have largely focused on data in a single cross-section or one round of a panel survey. Chen and Huffman (2010) show that food and drink prices significantly affect U.S. women’s probability of being obese but not for men. However, the impact of individual food and drink prices are not always as expected

CONSUMER HOME-USE EVALUATION OF A DEVELOPED LEAN GROUND BEEF PRODUCT

This study reports findings on the acceptance of a new lean ground beef product. Tested products involved 1) a Developed Lean product (less than 10% fat plus quality enhancers), 2) a Lean product (less than 10% fat without quality enhancers), and 3) a Market product (slightly more than 20% fat). These products were home delivered on a rotating basis to a random sample of 91 households, one product each week for three weeks. Product traits were evaluated by the household meal preparer at three stages of home use: preparing (5 traits), cooking (3 traits), and eating (4 traits), and by other household members at the final consumption stage of eating. More favorable ratings were observed for both Developed Lean and Lean products over the Market product at the preparing and cooking stages. Ratings at the eating stage were similar between the Developed Lean and the Market products indicating a favorable response to the Developed Lean product.Consumer/Household Economics,

Quantum Capacity Approaching Codes for the Detected-Jump Channel

The quantum channel capacity gives the ultimate limit for the rate at which quantum data can be reliably transmitted through a noisy quantum channel. Degradable quantum channels are among the few channels whose quantum capacities are known. Given the quantum capacity of a degradable channel, it remains challenging to find a practical coding scheme which approaches capacity. Here we discuss code designs for the detected-jump channel, a degradable channel with practical relevance describing the physics of spontaneous decay of atoms with detected photon emission. We show that this channel can be used to simulate a binary classical channel with both erasures and bit-flips. The capacity of the simulated classical channel gives a lower bound on the quantum capacity of the detected-jump channel. When the jump probability is small, it almost equals the quantum capacity. Hence using a classical capacity approaching code for the simulated classical channel yields a quantum code which approaches the quantum capacity of the detected-jump channel

Ponderosa pine forest reconstruction: Comparisons with historical data

Dendroecological forest reconstruction techniques are used to estimate presettlement structure of northern Arizona ponderosa pine forests. To test the accuracy of these techniques, we remeasured 10 of the oldest forest plots in Arizona, a subset of 51 historical plots established throughout the region from 1909 to 1913, and compared reconstruction outputs to historical data collected. Results of this analysis revealed several distinct sources of error: (1) After about 90 years, 94 percent of the recorded trees were relocated and remeasured, but approximately three trees/ha were missing in the field due to obliteration by fire or decay; (2) sizes of trees living in 1909 were overestimated by an average of 11.9 percent; (3) snag and log decomposition models tended to underestimate time since tree death by an undetermined amount; and (4) historical sizes of cut trees were difficult to estimate due to uncertainties concerning harvest dates. The aggregate effect of these errors was to overestimate the number of trees occurring in 1909-1913. Sensitivity analysis applied to decomposition equations showed variations in reconstructed sizes of snags and logs by +/- 7 percent and stand density estimates by 7 percent. Results suggest that these reconstruction techniques are robust but tend to overestimate tree size and forest density

Pinyon-juniper fire regime: Natural range of variability

In this study, we used a variety of methods to quantify and describe historical patterns of fire and forest structure in two pinyon-juniper ecosystems of the Southwest. Sites were located on the Kaibab National Forest in Arizona, south of Grand Canyon National Park (Tusayan), and on the Carson National Forest in New Mexico, north of Espanola (Canjilon). Methodological approaches included analysis of fire scars, contemporary forest structure, fire evidence, modern fire records, and forest reconstruction. GIS surface maps, constructed using inverse distance weighted interpolation, were used to assess spatial patterns of fire and forest structure. Results indicated distinct fire histories and recent forest changes at the two sites. At Tusayan, surface fires burned historically at frequencies of 7.2-7.4 years (Weibull median probability) in canyons and draws dominated by ponderosa pine. On uplands dominated by pinyon-juniper communities, longer point fire intervals suggested fires occurred at a mean frequency of 41.6 years. Point intervals stratified by species indicated longer return periods for Utah juniper than pinyon or ponderosa pine. Fire evidence in the form of charred tree structures was ubiquitous at the site and there was no clear relationship between stand age and fire evidence. Live, old trees (300 yr) were prevalent and averaged 26 trees per hectare (TPH). Stands were all ages up to 400 yr and patch sizes were generally small (30 ha). Reconstructions showed a moderate overall increase (39(percent)) in stand density since the late 19th century. Ponderosa pine increases were responsible for the majority of recent structural changes although pinyon density also had apparently increased. We found no evidence of extensive stand replacing fire over the last 400 years at Tusayan and concluded that the historical pattern has been one of frequent surface fires in ponderosa pine communities and small severe fires on pinyon-juniper uplands. At Canjilon, fire scar analysis showed longer mean fire intervals (81.1 yr), suggesting that infrequent crown fires or severe surface fires were an important component of the historical regime. Like Tusayan, charred structures were found across the Canjilon site, although they appeared to be more abundant at lower elevations where stands ages were younger. Few live old trees (300 yr) were found at the site (4.2 TPH). The site dominated by stands in the 200-250-yr and 250-300-yr age classes. Mean patch sizes for stands of these age classes were 24 and 79 ha, respectively. Reconstructions showed relatively greater increases in tree density (61(percent)) with Rocky Mountain juniper and pinyon pine both showing positive changes since the late 19th century. Evidence of stand replacing fire was seen along the eastern edge of the study site and young trees appeared to be encroaching into previously open areas, particularly around big sagebrush meadows. Woodland treatments that may parallel historical patterns of fire and forest structure at these sites include targeted tree thinning and/or use of prescribed fire to create canopy openings of various sizes

Overview of the Langley subsonic research effort on SCR configuration

Recent advances achieved in the subsonic aerodynamics of low aspect ratio, highly swept wing designs are summarized. The most significant of these advances was the development of leading edge deflection concepts which effectively reduce leading edge flow separation. The improved flow attachment results in substantial improvements in low speed performance, significant delay of longitudinal pitch up, increased trailing edge flap effectiveness, and increased lateral control capability. Various additional theoretical and/or experimental studies are considered which, in conjunction with the leading edge deflection studies, form the basis for future subsonic research effort

A Microscopic T-Violating Optical Potential: Implications for Neutron-Transmission Experiments

We derive a T-violating P-conserving optical potential for neutron-nucleus scattering, starting from a uniquely determined two-body $\rho$-exchange interaction with the same symmetry. We then obtain limits on the T-violating $\rho$-nucleon coupling $\overline{g}_{\rho}$ from neutron-transmission experiments in $^{165}$Ho. The limits may soon compete with those from measurements of atomic electric-dipole moments.Comment: 8 pages, 2 uuencoded figures in separate files (replaces version sent earlier in the day with figures attached), in RevTeX 3, submitted to PR

Constraints on a Parity-Conserving/Time-Reversal-Non-Conserving Interaction

Time-Reversal-Invariance non-conservation has now been unequivocally demonstrated in a direct measurement at CPLEAR. What about tests of time-reversal-invariance in systems other than the kaon system? Tests of time-reversal-invariance belong to two classes: searches for parity violating (P-odd)/time-reversal-invariance-odd (T-odd) interactions, and for P-even/T-odd interactions (assuming CPT conservation this implies C-conjugation non-conservation). Limits on a P-odd/T-odd interaction follow from measurements of the electric dipole moment of the neutron (with a present upper limit of 6 x 10^-26 e.cm [95% C.L.]). It provides a limit on a P-odd/T-odd pion-nucleon coupling constant which is less than 10^-4 times the weak interaction strength. Experimental limits on a P-even/T-odd interaction are much less stringent. Following the standard approach of describing the nucleon-nucleon interaction in terms of meson exchanges, it can be shown that only charged rho-meson exchange and A_1 meson exchange can lead to a P-even/T-odd interaction. The better constraints stem from measurements of the electric dipole moment of the neutron and from measurements of charge-symmetry breaking in neutron-proton elastic scattering. The latter experiments were executed at TRIUMF (497 and 347 MeV) and at IUCF (183 MeV). Weak decay experiments may provide limits which will possibly be comparable. All other experiments, like gamma decay experiments, detailed balance experiments, polarization - analyzing power difference determinations, and five-fold correlation experiments with polarized incident nucleons and aligned nuclear targets, have been shown to be at least an order of magnitude less sensitive.Comment: 15 pages LaTeX, including 5 PostScript figures. Uses ijmpe1.sty. To appear in International Journal of Modern Physics E (IJMPE). Slight change in short abstrac

From Skew-Cyclic Codes to Asymmetric Quantum Codes

We introduce an additive but not $\mathbb{F}_4$-linear map $S$ from $\mathbb{F}_4^{n}$ to $\mathbb{F}_4^{2n}$ and exhibit some of its interesting structural properties. If $C$ is a linear $[n,k,d]_4$-code, then $S(C)$ is an additive $(2n,2^{2k},2d)_4$-code. If $C$ is an additive cyclic code then $S(C)$ is an additive quasi-cyclic code of index $2$. Moreover, if $C$ is a module $\theta$-cyclic code, a recently introduced type of code which will be explained below, then $S(C)$ is equivalent to an additive cyclic code if $n$ is odd and to an additive quasi-cyclic code of index $2$ if $n$ is even. Given any $(n,M,d)_4$-code $C$, the code $S(C)$ is self-orthogonal under the trace Hermitian inner product. Since the mapping $S$ preserves nestedness, it can be used as a tool in constructing additive asymmetric quantum codes.Comment: 16 pages, 3 tables, submitted to Advances in Mathematics of Communication