Information Processing is not Affected by Multiple Concussions in College Age Students

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Mental Health is not Affected by Multiple Concussions in Young Adults

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RFD-SF and Time to Peak Force for Grip Strength is not affected in College Aged Students with Multiple Concussions

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The Ecology of Celtis reticulata Torr. (Netleaf hackberry) in Idaho

The ecology of netleaf hackberry (Celtis reticulata Torr.) is poorly known throughout its broad western range. To gain some understanding of the species' basic ecology, three components of its life history were studied. First, seed germination requirements were analyzed under laboratory conditions. Second, hackberry population dynamics were evaluated from tree size and age structures. Lastly, an examination of hackberry's response to fire was made, using tree-level post-fire data. A higher percentage of non-stratified hackberry seed germinates if the seed is mechanically scarified. While germination percent is low, the treatment may eliminate the 120-day stratification period recommended by some authorities. Even with cold stratification, germination is usually quite low for Celtis species. Fermenting fruits for 72 hours and subsequent depulping prior to scarification did not significantly increase germination levels, as hypothesized. However, seed that was not scarified but was fermented with its pulp intact germinated at a higher rate than the non-fermented, non-scarified seed. This result may be significant to its biology. Seed is typically cleaned prior to planting by seed distributors. However, hackberry seed with its pulp retained may in fact have a superior germination rate, as it is allowed to undergo natural processes of fermentation resulting from moist field conditions. In Idaho, hackberry's uniquely fragmented distribution appears to be controlled by a variety of factors. Hackberry is generally restricted to semi-arid portions of the state where temperatures are least severe during the winter months, such as in moderated river canyons, or at elevations below 1600 m. It occurs in a variety of habitats, from riparian to upland, however it is most abundant on sites with a southeast-to southwesterly aspect and a rocky surface cover. The presence of rock below the surface may be equally important, but this factor was not quantified. Hackberry is a slow-growing species in Idaho, averaging 3.9 m tall at 50 years. Differences in hackberry growth rate under a variety of site conditions were evaluated by a site index constructed from the log-log regression of height on age. Trees reach maximum heights where topographic shelter is greatest, such as in draws, and where soils are loamy. However, well-drained soils may be important, as nearly all soils had some sand or skeletal component. Hackberry can be long-lived, with the maximum age recorded at 374 years; the average age was 66 years (N = 959 trees). Hackberry appears to be reproducing, in spite of habitat degradation caused by livestock overgrazing, alien plant invasion, and increasing fire frequencies. However, newly established even-aged stands are rare and are generally found along waterways on stream terraces or at high water lines. In these areas, surface rock cover was typically high, with the rock providing a moderated below-ground microclimate, as well as protection from herbivores. Recruitment is favored by rockiness at the surface, but growth rates of established individuals are not higher with more surface rock. Under severe livestock grazing pressure, stands had a single dominant cohort and lowered recruitment. Fire-caused mortality of hackberry growing in low density stands appears to be uncommon in Idaho. In nine burns, only 8% of the trees (N = 161) were dead after the fires. This mortality, however, cannot be attributed solely to fire, as pre-burn vigor was not evaluated. Individuals typically persist or resprout following fire. Mortality rates were highest for individuals with a high percent cover of live vegetation below their canopy. Temperatures were probably more intense within the live vegetation, where the fire could feasibly linger long enough to kill the roots of the associated hackberry. While burns in high density stands were not observed, these burns could result in greater mortality, due to their greater continuity of plant cover

Calmodulin-Mediated Signal Transduction Pathways in \u3ci\u3eArabidopsis\u3c/i\u3e Are Fine-Tuned by Methylation

Calmodulin N-methyltransferase (CaM KMT) is an evolutionarily conserved enzyme in eukaryotes that transfers three methyl groups to a highly conserved lysyl residue at position 115 in calmodulin (CaM). We sought to elucidate whether the methylation status of CaM plays a role in CaM-mediated signaling pathways by gene expression analyses of CaM KMT and phenotypic characterization of Arabidopsis thaliana lines wherein CaM KMT was overexpressed (OX), partially silenced, or knocked out. CaM KMT was expressed in discreet spatial and tissue-specific patterns, most notably in root tips, floral buds, stamens, apical meristems, and germinating seeds. Analysis of transgenic plants with genetic dysfunction in CaM KMT revealed a link between the methylation status of CaM and root length. Plants with suppressed CaM methylation had longer roots and CaM KMT OX lines had shorter roots than wild type (Columbia-0). CaM KMT was also found to influence the root radial developmental program. Protein microarray analyses revealed a number of proteins with specificity for methylated forms of CaM, providing candidate functional intermediates between the observed phenotypes and the target pathways. This work demonstrates that the functionality of the large CaM family in plants is fine-tuned by an overarching methylation mechanism

Structural Probe of a Glass Forming Liquid: Generalized Compressibility

We introduce a new quantity to probe the glass transition. This quantity is a linear generalized compressibility which depends solely on the positions of the particles. We have performed a molecular dynamics simulation on a glass forming liquid consisting of a two component mixture of soft spheres in three dimensions. As the temperature is lowered (or as the density is increased), the generalized compressibility drops sharply at the glass transition, with the drop becoming more and more abrupt as the measurement time increases. At our longest measurement times, the drop occurs approximately at the mode coupling temperature $T_C$. The drop in the linear generalized compressibility occurs at the same temperature as the peak in the specific heat. By examining the inherent structure energy as a function of temperature, we find that our results are consistent with the kinetic view of the glass transition in which the system falls out of equilibrium. We find no size dependence and no evidence for a second order phase transition though this does not exclude the possibility of a phase transition below the observed glass transition temperature. We discuss the relation between the linear generalized compressibility and the ordinary isothermal compressibility as well as the static structure factor.Comment: 18 pages, Latex, 26 encapsulated postscript figures, revised paper is shorter, to appear in Phys. Rev.

Using Microbial Community Interactions within Plant Microbiomes to Advance an Evergreen Agricultural Revolution

Innovative plant breeding and technology transfer fostered the Green Revolution (GR), which transformed agriculture worldwide by increasing grain yields in developing countries. The GR temporarily alleviated world hunger, but also reduced biodiversity, nutrient cycling, and carbon (C) sequestration that agricultural lands can provide. Meanwhile, economic disparity and food insecurity within and among countries continues. Subsequent agricultural advances, focused on objectives such as increasing crop yields or reducing the risk of a specific pest, have failed to meet food demands at the local scale or to restore lost ecosystem services. An increasing human population, climate change, growing per capita food and energy demands, and reduced ecosystem potential to provide agriculturally relevant services have created an unrelenting need for improved crop production practices. Meeting this need in a sustainable fashion will require interdisciplinary approaches that integrate plant and microbial ecology with efforts to advance crop production while mitigating effects of a changing climate. Metagenomic advances are revealing microbial dynamics that can simultaneously improve crop production and soil restoration while enhancing crop resistance to environmental change. Restoring microbial diversity to contemporary agroecosystems could establish ecosystem services while reducing production costs for agricultural producers. Our framework for examining plant-microbial interactions at multiple scales, modeling outcomes to broadly explore potential impacts, and interacting with extension and training networks to transfer microbial based agricultural technologies across socioeconomic scales, offers an integrated strategy for advancing agroecosystem sustainability while minimizing potential for the kind of negative ecological and socioeconomic feedbacks that have resulted from many widely adopted agricultural technologies

Evidence for structural and electronic instabilities at intermediate temperatures in κ\kappa-(BEDT-TTF)2_{2}X for X=Cu[N(CN)2_{2}]Cl, Cu[N(CN)2_{2}]Br and Cu(NCS)2_{2}: Implications for the phase diagram of these quasi-2D organic superconductors

We present high-resolution measurements of the coefficient of thermal expansion $\alpha (T)=\partial \ln l(T)/\partial T$ of the quasi-twodimensional (quasi-2D) salts $\kappa$-(BEDT-TTF)$_2$X with X = Cu(NCS)$_2$, Cu[N(CN)$_2$]Br and Cu[N(CN)$_2$]Cl. At intermediate temperatures (B), distinct anomalies reminiscent of second-order phase transitions have been found at $T^\ast = 38$ K and 45 K for the superconducting X = Cu(NCS)$_2$ and Cu[N(CN)$_2$]Br salts, respectively. Most interestingly, we find that the signs of the uniaxial pressure coefficients of $T^\ast$ are strictly anticorrelated with those of $T_c$. We propose that $T^\ast$ marks the transition to a spin-density-wave (SDW) state forming on minor, quasi-1D parts of the Fermi surface. Our results are compatible with two competing order parameters that form on disjunct portions of the Fermi surface. At elevated temperatures (C), all compounds show $\alpha (T)$ anomalies that can be identified with a kinetic, glass-like transition where, below a characteristic temperature $T_g$, disorder in the orientational degrees of freedom of the terminal ethylene groups becomes frozen in. We argue that the degree of disorder increases on going from the X = Cu(NCS)$_2$ to Cu[N(CN)$_2$]Br and the Cu[N(CN)$_2$]Cl salt. Our results provide a natural explanation for the unusual time- and cooling-rate dependencies of the ground-state properties in the hydrogenated and deuterated Cu[N(CN)$_2$]Br salts reported in the literature.Comment: 22 pages, 7 figure

Anomalously large oxygen-ordering contribution to the thermal expansion of untwinned YBa2Cu3O6.95 single crystals: a glass-like transition near room temperature

We present high-resolution capacitance dilatometry studies from 5 - 500 K of untwinned YBa2Cu3Ox (Y123) single crystals for x ~ 6.95 and x = 7.0. Large contributions to the thermal expansivities due to O-ordering are found for x ~ 6.95, which disappear below a kinetic glass-like transition near room temperature. The kinetics at this glass transition is governed by an energy barrier of 0.98 +- 0.07 eV, in very good agreement with other O-ordering studies. Using thermodynamic arguments, we show that O-ordering in the Y123 system is particularly sensitive to uniaxial pressure (stress) along the chain axis and that the lack of well-ordered chains in Nd123 and La123 is most likely a consequence of a chemical-pressure effect.Comment: 4 pages, 3 figures, submitted to PR

Effect of Modification of the NI Artificial Diet on the Biological Fitness Parameters of Mass Reared Western Tarnished Plant Bug, Lygus hesperus

The NI artificial diet is the only known successful diet for mass rearing the western tarnished plant bug, Lygus hesperus Knight (Hemiptera: Miridae). This diet has been used for more than a decade. However, because it contains cooked chicken egg, and thus requires laborious preparation (Cohen 2000), this diet is difficult to use. Three modifications (D1, D2, D3) of the NI diet were investigated in hopes of developing a more easily prepared diet that avoids the cooked egg and improves mass fitness parameters of L. hesperus. The modified D3 diet, containing autoclaved chicken egg yolk based component, had the highest egg/cage/day production (13120 ± 812 SE). This was significantly greater than diets D1, containing autoclaved dry chicken egg yolk based component (9027 ± 811 SE), D2, containing autoclaved chicken egg white based component (8311 ± 628 SE), and NI, which contained autoclaved chicken egg yolk + cooked egg diet (7890 ± 761 SE). Significant differences were observed in the weights of all developmental stages except for eggs and first instar nymphs. Higher rates of fertility, hatchability, and low mortality in nymphs during the first instar were also obtained in the modified D3 diet. The results clearly indicated that the D3 diet provided an opportunity to significantly reduce rearing cost by avoiding time-consuming issues with preparation of a cooked egg diet. This should result in an increase in production capacity and a reduction in production costs