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Among the DTM-based parsimonious floodplain delineation methods, hydrogeomorphic scaling laws, providing consistent flood flow depth estimations as a function of contributing drainage areas, are widely used. Recent advances in this field demonstrated the suitability of hydrogeomorphic floodplain delineation models from basin to continental scale across diverse climatic and morphological settings. However, the sensitivity of scaling law parameterizations and performance in semi-arid to humid and low-gradient to steep basins is still unknown. In this work we determined flow depths – contributing areas scaling law parameters with varying basin slope and average annual rainfall across eleven basins in the west-central United States. These variable scaling law parameters were used to test the performance of the GFPLAIN hydrogeomorphic floodplain delineation model in the study area adopting largely and freely available global climate and topographic datasets. Outcomes of this analysis show improved performances and effectiveness of the GFPLAIN model with varying morphometric and climatic factors suggesting room for improvement for the current continental and global hydrogeomorphic floodplain datasets.

Environmental flows are commonly defined as the river-flow characteristics necessary to maintain the integrity of riverine ecosystems. The concept of environmental flows has evolved over the past half-century, beginning with the development of minimum instream flows necessary to protect a single fish species to current frameworks for holistically including all aspects of river health that depend on natural flow regimes. This also includes the interaction of terrestrial environments with riverine ecosystems during large flooding events. The challenges associated with defining and implementing environmental flows are numerous, and they sometimes lack data necessary to define flow-ecology relationships, appropriate temporal and spatial scales for environmental flow applications, and incorporate environmental flows into water management policy. Given these challenges, researchers and practitioners have made incredible advances in better understanding the relationships between river health and flow dynamics, including the links among flow, sediment, temperature, and human activities. In addition, computational advances have allowed researchers to more accurately model flow-habitat relationships at fine scales, providing a more complete understanding of the connection between flow and habitat needs for riverine species. All these advances benefit from holistic frameworks that guide environmental flow development and applications while considering the needs of other water uses in a river system. This article presents relevant studies regarding approaches for developing environmental flows, relationships between riverine ecology and flow dynamics, and policy frameworks and tools useful for implementing environmental flows in practice.

The complexity of maize domestication Maize originated in what is now central Mexico about 9000 years ago and spread throughout the Americas before European contact. Kistler et al. applied genomic analysis to ancient and extant South American maize lineages to investigate the genetic changes that accompanied domestication (see the Perspective by Zeder). The origin of modern maize cultivars likely involved a “semidomesticated” lineage that moved out of Mexico. Later improvements then occurred among multiple South American populations, including those in southwestern Amazonia. Science , this issue p. 1309 ; see also p. 1246

Context: Balance testing is a vital component in the evaluation and management of sport-related concussion. Few studies have examined the use of objective, low-cost, force-plate balance systems and changes in balance after a competitive season. Objective: To examine the extent of preseason versus postseason static balance changes using the Balance Tracking System (BTrackS) force plate in college athletes. Design: Pretest, posttest design. Setting: Athletic training facility. Participants: A total of 47 healthy, Division-I student-athletes (33 males and 14 females; age 18.4 [0.5] y, height 71.8 [10.8] cm, weight 85.6 [21.7] kg) participated in this study. Main Outcome Measures: Total center of pressure path length was measured preseason and postseason using the BTrackS force plate. A Wilcoxon signed-rank test was conducted to examine preseason and postseason changes. SEM and minimal detectable change were also calculated. Results: There was a significant difference in center of pressure path length differed between preseason (24.6 [6.8] cm) and postseason (22.7 [5.4] cm) intervals (P = .03), with an SEM of 3.8 cm and minimal detectable change of 10.5 cm. Conclusions: Significant improvements occurred for center of pressure path length after a competitive season, when assessed using the BTrackS in a sample of college athletes. Further research is warranted to determine the effectiveness of the BTrackS as a reliable, low-cost alternative to force-plate balance systems. In addition, clinicians may need to update baseline balance assessments more frequently to account for improvements.

We use multi-million-atom molecular dynamics (MD) simulations with an embedded atom model potential parameterized for NiAl to study temperature- and stress-induced martensitic phase transformations in nanocrystalline shape memory alloys. Nucleation of the martensite phase occurs in the grain interiors and grows outward up to the point where further transformation is hindered by the constraints imposed by neighboring grains. Decreasing grain size inhibits the transformation process and the temperature-induced transformation is completely suppressed for samples with average grain sizes of 7.5 nm and less. Interestingly, mechanical loads can induce the martensitic transformation in samples with ultra-fine grains and, quite surprisingly, the sample with 7.5 nm grain size exhibits improved, ultra-fast, superelasticity as compared with its coarser grain counterparts. The simulations provide a picture of the processes that govern the performance and fundamental limits of nanocrystalline shape memory alloys with atomistic resolution.

We use molecular dynamics (MD) with an embedded atom model potential parameterized for NiAl to study martensitic phase transformations in a disordered shape memory alloy. We focus on the role of intrinsic atomic-level variability and mechanical constraints on the martensite and austenite transformation temperatures and on the martensite microstructure for specimens with varying size. We find that periodic system size has a weak effect on transformation temperature all the way to the nanometer scale, with the entropy-stabilized austenite phase slightly penalized with decreasing size. Atomic-level variability in these random alloys leads to significant sample-tosample variability in transformation temperature. The uncertainty in the austenite transformation temperature increases with decreasing size, reaching similar to,10% of the mean value for samples 10 nm on the side. Interestingly, the variability of the high-temperature martensite transition shows little size dependence. We find that a critical size of similar to 40 nm is required to develop multidomain martensite microstructures, and mechanical constraints reduce this critical size to similar to 17 nm, while significantly affecting the transformation temperatures. These results contribute to the understanding of martensitic transformation in nanocrystalline samples and of the fundamental limits of miniaturization of these alloys. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Herein we report the synthesis and characterization of a novel series of N-phenylsulfonyl-1H-pyrrole picolinamides as novel positive allosteric modulators of mGlu4. We detail our work towards finding phenyl replacements for the core scaffold of previously reported phenyl sulfonamides and phenyl sulfone compounds. Our efforts culminated in the identification of N-(1-((3,4-dimethylphenyl)sulfonyl)-1H-pyrrol-3-yl)picolinamide as a potent PAM of mGlu4.

Polyamines spermine and spermidine are highly regulated, ubiquitous aliphatic cations that maintain DNA structure and function as immunomodulators and as antioxidants. Polyamine homeostasis is disrupted after brain injuries, with concomitant generation of toxic metabolites that may contribute to secondary injuries. To test the hypothesis of increased brain polyamine catabolism after traumatic brain injury (TBI), we determined changes in catabolic enzymes and polyamine levels in the rat brain after lateral controlled cortical impact TBI. Spermine oxidase (SMO) catalyzes the degradation of spermine to spermidine, generating H2O2 and aminoaldehydes. Spermidine/spermine-N(1)-acetyltransferase (SSAT) catalyzes acetylation of these polyamines, and both are further oxidized in a reaction that generates putrescine, H2O2, and aminoaldehydes. In a rat cortical impact model of TBI, SSAT mRNA increased subacutely (6-24 h) after TBI in ipsilateral cortex and hippocampus. SMO mRNA levels were elevated late, from 3 to 7 days post-injury. Polyamine catabolism increased as well. Spermine levels were normal at 6 h and decreased slightly at 24 h, but were normal again by 72 h post-injury. Spermidine levels also decreased slightly (6-24 h), then increased by approximately 50% at 72 h post-injury. By contrast, normally low putrescine levels increased up to sixfold (6-72 h) after TBI. Moreover, N-acetylspermidine (but not N-acetylspermine) was detectable (24-72 h) near the site of injury, consistent with increased SSAT activity. None of these changes were seen in the contralateral hemisphere. Immunohistochemical confirmation indicated that SSAT and SMO were expressed throughout the brain. SSAT-immunoreactivity (SSAT-ir) increased in both neuronal and nonneuronal (likely glial) populations ipsilateral to injury. Interestingly, bilateral increases in cortical SSAT-ir neurons occurred at 72 h post-injury, whereas hippocampal changes occurred only ipsilaterally. Prolonged increases in brain polyamine catabolism are the likely cause of loss of homeostasis in this pathway. The potential for simple therapeutic interventions (e.g., polyamine supplementation or inhibition of polyamine oxidation) is an exciting implication of these studies.

Reports that under a third of the increasing numbers of US citizens needing long‐term care (LTC) in a nursing home pay their own fees; and that Medicaid (health programme for the poor) meets over half of LTC costs. Describes the rules applied to qualify for Medicaid LTC payments, the growth of “Medicaid estate planning” to shield the income/assets of the middle classes so that they can qualify and the actions taken by the government to restrict misuse of Medicaid and reduce its costs. Explains methods which are still being used to protect middle class income/assets without losing Medicaid eligibility; and the alternative of private LTC insurance, including its tax implications. Discusses efforts to develop a partnership between Medicaid and the insurance companies in some states; and the pros and cons of the plans available for both individuals and the government.

Background Traumatic brain injury (TBI) induces arachidonic acid (ArA) release from cell membranes. ArA metabolites form a class of over 50 bioactive eicosanoids that can induce both adaptive and/or maladaptive brain responses. The dynamic metabolism of ArA to eicosanoids, and how they affect the injured brain, is poorly understood due to their diverse activities, trace levels, and short half-lives. The eicosanoids produced in the brain postinjury depend upon the enzymes present locally at any given time. Eicosanoids are synthesized by heme-containing enzymes, including cyclooxygenases, lipoxygenases, and arachidonate monoxygenases. The latter comprise a subset of the cytochrome P450 “Cyp” gene family that metabolize fatty acids, steroids, as well as endogenous and exogenous toxicants. However, for many of these genes neither baseline neuroanatomical nor injury-related temporal expression have been studied in the brain. In a rat model of parietal cortex TBI, Cyp and eicosanoid-related mRNA levels were determined at 6 h, 24 h, 3d, and 7d postinjury in parietal cortex and hippocampus, where dynamic changes in eicosanoids have been observed. Quantitative real-time polymerase chain reaction with low density arrays were used to assay 62 rat Cyps, 37 of which metabolize ArA or other unsaturated fatty acids; 16 eicosanoid-related enzymes that metabolize ArA or its metabolites; 8 eicosanoid receptors; 5 other inflammatory- and recovery-related genes, plus 2 mouse Cyps as negative controls and 3 highly expressed “housekeeping” genes. Results Sixteen arachidonate monoxygenases, 17 eicosanoid-related genes, and 12 other Cyps were regulated in the brain postinjury (p Conclusions The results suggest complex regulation of ArA and other lipid metabolism after TBI. Due to the temporal nature of brain injury-induced Cyp gene induction, manipulation of each gene (or its products) at a given time after TBI will be required to assess their contributions to secondary injury and/or recovery. Moreover, a better understanding of brain region localization and cell type-specific expression may be necessary to deduce the role of these eicosanoid-related genes in the healthy and injured brain.