Estimating the Impacts of Storage Dry Matter Losses on Switchgrass Production

This poster estimates dry matter losses as a function of harvest method, storage treatment, and time in storage. We then calculate the cost to store switchgrass bales under alternate harvest method and storage treatment scenarios; and determine the breakeven harvest method and storage treatment as a function of biomass price and time in storage.Biomass, bioenergy crops, function form, sustainable systems, Farm Management, Production Economics, Q10, Q42,

Ferromagnetically coupled dimers on the distorted Shastry-Sutherland lattice: Application to (CuCl)LaNb2O7

A recent study [Tassel {\it et al.}, Phys. Rev. Lett. {\bf 105}, 167205 (2010)] has proposed a remarkable spin model for (CuCl)LaNb2O7, in which dimers are ferromagnetically coupled to each other on the distorted Shastry-Sutherland lattice. In this model, the intra-dimer exchange coupling J>0 is antiferromagnetic, while the inter-dimer exchange couplings are ferromagnetic and take different values, J_x,J_y<0, in the two bond directions. Anticipating that the highly frustrated character of this model may lead to a wide range of behaviors in (CuCl)LaNb2O7 and related compounds, we theoretically investigate the ground state phase diagram of this model in detail using the following three approaches: a strong-coupling expansion for small J_x and J_y, exact diagonalization for finite clusters, and a Schwinger boson mean field theory. When |J_x|, |J_y| <~ J, the system stays in a dimer singlet phase with a finite spin gap. This state is adiabatically connected to the decoupled-dimer limit J_x=J_y=0. We show that the magnetization process of this phase depends crucially on the spatial anisotropy of the inter-dimer couplings. The magnetization shows a jump or a smooth increase for weak and strong anisotropy, respectively, after the spin gap closes at a certain magnetic field. When |J_x| or |J_y| >~ J, quantum phase transitions to various magnetically ordered phases (ferromagnetic, collinear stripe, and spiral) occur. The Schwinger boson analysis demonstrates that quantum fluctuations split the classical degeneracy of different spiral ground states. Implications for (CuCl)LaNb2O7 and related compounds are discussed in light of our theoretical results and existing experimental data.Comment: 21 pages, 20 figure

Is Switchgrass Yield Response to Nitrogen Fertilizer Dynamic? Implications for Profitability and Sustainability at the Farm Level

Revised version of the paper submitted 2/11/2010Biomass, Energy Crops, Sequential Inputs, West Tennessee, Crop Production/Industries, Farm Management, Production Economics, Resource /Energy Economics and Policy,

Athletic pubalgia and associated rehabilitation

BACKGROUND: Evaluation and treatment of groin pain in athletes is challenging. The anatomy is complex, and multiple pathologies often coexist. Different pathologies may cause similar symptoms, and many systems can refer pain to the groin. Many athletes with groin pain have tried prolonged rest and various treatment regimens, and received differing opinions as to the cause of their pain. The rehabilitation specialist is often given a non-specific referral of groin pain or sports hernia. The cause of pain could be as simple as the effects of an adductor strain, or as complex as athletic pubalgia or inguinal disruption. The term sports hernia is starting to be replaced with more specific terms that better describe the injury. Inguinal disruption is used to describe the syndromes related to the injury of the inguinal canal soft tissue environs ultimately causing the pain syndrome. The term athletic pubalgia is used to describe the disruption and/or separation of the more medial common aponeurosis from the pubis, usually with some degree of adductor tendon pathology. TREATMENT: Both non-operative and post-operative treatment options share the goal of returning the athlete back to pain free activity. There is little research available to reference for rehabilitation guidelines and creation of a plan of care. Although each surgeon has their own specific set of post-operative guidelines, some common concepts are consistent among most surgeons. Effective rehabilitation of the high level athlete to pain free return to play requires addressing the differences in the biomechanics of the dysfunction when comparing athletic pubalgia and inguinal disruption. CONCLUSION: Proper evaluation and diagnostic skills for identifying and specifying the difference between athletic pubalgia and inguinal disruption allows for an excellent and efficient rehabilitative plan of care. Progression through the rehabilitative stages whether non-operative or post-operative allows for a focused rehabilitative program. As more information is obtained through MRI imaging and the diagnosis and treatment of inguinal disruption and athletic pubalgia becomes increasingly frequent, more research is warranted in this field to better improve the evidence based practice and rehabilitation of patients. LEVELS OF EVIDENCE: 5

Switchgrass Production in Marginal Environments: A Comparative Economic Analysis across Four West Tennessee Landscapes

Switchgrass (Panicum virgatum L.) has been identified as a model feedstock for the emerging biofuels industry. Its selection was based, in part, upon the observation that switchgrass can produce high yields in marginal production environments. This trait may become particularly valuable in coming years, as renewable fuel mandates begin to take effect and concerns over the food-versus-fuel debate increase. Relatively little research information exists about how management practices and production costs vary across different production environments. The objectives of this research were (a) to compare switchgrass yields as influenced by seeding rate and nitrogen fertilization rates in low-, intermediate-, and high-yielding switchgrass production environments, (b) to determine the economically optimal seeding rate and nitrogen fertilization rate for each environment, and (c) to calculate per-ton production costs. Experimental yield data from four locations were utilized for this study. Plots were seeded in 2004 with treatments of 2.5, 5.0, 7.5, 10.0, and 12.5 lbs/acre. Nitrogen was applied in subsequent intervals at 0, 60, 120 and 180 lbs/acre. For an expected stand lifespan of 10 years, production costs ranged from $45 per ton in a well drained level upland environment ideal for the production of row crops to$70 per ton in a marginal, poorly drained flood plain in which the switchgrass stand was slow to establish and which demonstrated lower overall yields.Crop Production/Industries, International Relations/Trade,

Genome-Wide Association Study and Pathway-Level Analysis of Kernel Color in Maize.

Rapid development and adoption of biofortified, provitamin A-dense orange maize (Zea mays L.) varieties could be facilitated by a greater understanding of the natural variation underlying kernel color, including as it relates to carotenoid biosynthesis and retention in maize grain. Greater abundance of carotenoids in maize kernels is generally accompanied by deeper orange color, useful for distinguishing provitamin A-dense varieties to consumers. While kernel color can be scored and selected with high-throughput, low-cost phenotypic methods within breeding selection programs, it remains to be well established as to what would be the logical genetic loci to target for selection for kernel color. We conducted a genome-wide association study of maize kernel color, as determined by colorimetry, in 1,651 yellow and orange inbreds from the Ames maize inbred panel. Associations were found with y1, encoding the first committed step in carotenoid biosynthesis, and with dxs2, which encodes the enzyme responsible for the first committed step in the biosynthesis of the isoprenoid precursors of carotenoids. These genes logically could contribute to overall carotenoid abundance and thus kernel color. The lcyE and zep1 genes, which can affect carotenoid composition, were also found to be associated with colorimeter values. A pathway-level analysis, focused on genes with a priori evidence of involvement in carotenoid biosynthesis and retention, revealed associations for dxs3 and dmes1, involved in isoprenoid biosynthesis; ps1 and vp5, within the core carotenoid pathway; and vp14, involved in cleavage of carotenoids. Collectively, these identified genes appear relevant to the accumulation of kernel color

A High-Resolution Study of the HI Content of Local Group Dwarf Irregular Galaxy WLM

Dwarf irregular galaxies are unique laboratories for studying the interaction between stars and the interstellar medium in low mass environments. We present the highest spatial resolution observations to date of the neutral hydrogen content of the Local Group dwarf irregular galaxy WLM. We find that WLM's neutral hydrogen distribution is typical for a galaxy of its type and size and derive an HI mass of 6.3e7 Msun for WLM. In addition, we derive an HI extent for WLM of 30 arcmin, which is much less than the 45 arcmin extent found by Huchtmeier, Seiradakis, and Materne (1981). We show that the broken ring of high column density neutral hydrogen surrounding the center of WLM is likely the result of star formation propagating out from the center of the galaxy. The young stars and Ha emission in this galaxy are mostly correlated with the high column density neutral hydrogen. The gap in the central ring is the result of star formation in that region using up, blowing out, or ionizing all of the neutral hydrogen. Like many late-type galaxies, WLM's velocity field is asymmetric with the approaching (northern) side appearing to be warped and a steeper velocity gradient for the approaching side than for the receding side in the inner region of the galaxy. We derive a dynamical mass for WLM of 2.16e9 Msun.Comment: 38 pages, 15 figures, 5 tables, accepted by AJ, high resolution version at http://www.astro.wisc.edu/~kepley/kepley_wlm.p

Feeling Tired?: How Sharing Positive Experiences Can Boost Vitality

Three studies indicated how sharing positive experiences can boost vitality

Fibrous dysplasia in a Monkey

Fibrous dysplasia is a syndrome characterized by dysplastic fibro-osseous skeletal changes. The syndrome has been described in the literature under a number of different terms including osteodystrophia fibrosa, polyostotic osteitis fibrosa, regional fibrocystic disease, osteitis fibrosa cystica, and fibrous dysplasia. The disease has been reported in dogs, horses, swine, monkeys and man