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Search Results: 1 - 10 of 342573 matches for " R. H. White "
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The NLC Software Requirements Methodology
G. R. White,H. Shoaee
Physics , 2001,
Abstract: We describe the software requirements and development methodology developed for the NLC control system. Given the longevity of that project, and the likely geographical distribution of the collaborating engineers, the planned requirements management process is somewhat more formal than the norm in high energy physics projects. The short term goals of the requirements process are to accurately estimate costs, to decompose the problem, and to determine likely technologies. The long term goal is to enable a smooth transition from high level functional requirements to specific subsystem and component requirements for individual programmers, and to support distributed development. The methodology covers both ends of that life cycle. It covers both the analytical and documentary tools for software engineering, and project management support.
Modification of the Brief Smell Identification Test by Introduction of a Placebo  [PDF]
Grete Kjelvik, Ole Bosnes, Ragnhild Omli, Liv Heidi Skotnes, Asta K. H?berg, Linda R. White
Neuroscience & Medicine (NM) , 2012, DOI: 10.4236/nm.2012.32017
Abstract: Objective: To introduce the concept that there might be “nothing to smell” to the Brief Smell Identification Test (B-SIT), with a view to masking olfactory deficits, particularly from healthy control participants in research studies. Methods: Seventy-one elderly individuals, healthy for their age, were recruited to the study. They were blindfolded and carried out a modified B-SIT where one item had been replaced with a placebo, and one odour alternative answer to three other items was replaced by the alternative “none/other” (actual odour unchanged). Results: There was no overall difference in the median or mean score achieved by the cohort compared to results obtained previously using the conventional B-SIT. The replacement of the item “turpentine” with a placebo resulted in an improved score for the item in a Norwegian setting. The overall scores were not improved. Conclusions: It is possible to introduce the concept that there may be “nothing to smell” to the B-SIT without compromising the test for healthy control individuals. This may be a more appropriate approach to olfactory testing of control individuals or patients with suspected early neurodegenerative diseases.
Mineral absorption in relation to nutritional ecology of reindeer
H. Staaland,K. Hove,R. G. White
Rangifer , 1986,
Abstract: This paper addresses the way which absorption of minerals relate to nutritional ecology and mineral conservation processes. A latin square designed experiment was used to assess the effects of diet on mineral (Ca, Mg, K, Na) absorption processes in reindeer (Rangifer tarandus L.). Three male calves were fed 3 different diets: concentrate with 25% grass meal (RF-71), lichens, and a mixed diet of lichens and RF-71. Two other male calves were fed the lichen or mixed diet, supplemented with 4 g Ca/day. Ca supplementation significantly increased fecal Ca excretion, reduced the excretion of K and Mg, but had no significant effect on Na excretion. Rates of intake and fecal exretion of Ca, Mg and K were highly correlated (P<0.001), while no correlations were found for Na. Negative digestibilities of Ca, Mg and K, and a positive Na digestibility were noted for the lichen diet. For the other diets, all minerals were in positive digestibility, and Ca supplements increased the digestibility of all minerals. Digesta from different sections of the alimentary tract were collected after termination of the experiment. Alimentary pools of Ca and K were equal for animals fed lichen or RF-71, whereas the Na pool was largest on the lichen diet and the Mg pool largest on the RF-71 diet. Rumen turnover time (rumen mineral pool size/daily mineral intake) was consistently less than 3 days for Ca and Mg, but was 22 and 82 days for Na on the RF-71 and lichen diets respectively. Estimates of mineral exchange in various parts of the tract showed that the intestines play and important role in scavanging endogenously secreted minerals. Results are discussed with respect to mineral binding by lichens and the possible role of natural mineral supplements in the nutritional ecology of reindeer.
Calcium absorption in reindeer: Effect of diet and vitamin D
K. Hove,H. Staaland,R. G. White
Rangifer , 1986,
Field Assessment and Specification Review for Roller-Integrated Compaction Monitoring Technologies
David J. White,Pavana K. R. Vennapusa,Heath H. Gieselman
Advances in Civil Engineering , 2011, DOI: 10.1155/2011/783836
Abstract: Roller-integrated compaction monitoring (RICM) technologies provide virtually 100-percent coverage of compacted areas with real-time display of the compaction measurement values. Although a few countries have developed quality control (QC) and quality assurance (QA) specifications, broader implementation of these technologies into earthwork construction operations still requires a thorough understanding of relationships between RICM values and traditional in situ point test measurements. The purpose of this paper is to provide: (a) an overview of two technologies, namely, compaction meter value (CMV) and machine drive power (MDP); (b) a comprehensive review of field assessment studies, (c) an overview of factors influencing statistical correlations, (d) modeling for visualization and characterization of spatial nonuniformity; and (e) a brief review of the current specifications. 1. Introduction Roller-integrated compaction monitoring (RICM) technologies refer to sensor measurements integrated into compaction machines. Work in this area was initiated over 30 years ago in Europe for smooth drum rollers compacting granular soils and involved instrumenting the roller with an accelerometer and calculating the ratio of the fundamental frequency to the first harmonic [1, 2]. Modern sensor technologies, computers, and global positioning system (GPS) technologies now make it possible to collect, transmit, and visualize a variety of RICM measurements in real time. As a quality assessment tool for compaction of earth materials, these technologies offer tremendous potential for field controlling the construction process to meet performance quality standards. Recent efforts in the United States (US) have focused attention on how RICM technologies can be used in road building [3–5] and relating selected RICM parameters to mechanistic pavement design values. Several manufactures currently offer RICM technologies on smooth drum vibratory roller configurations for compaction of granular materials and asphalt, and nonvibratory roller configurations for compaction of cohesive materials. The current technologies calculate: (1) an index value based on a ratio of selected frequency harmonics for a set time interval for vibratory compaction [1, 2], (2) ground stiffness or dynamic elastic modulus based on a drum-ground interaction model for vibratory compaction [6–8], or (3) a measurement of rolling resistance calculated from machine drive power (MDP) for vibratory and nonvibratory compaction [9]. When the accelerometer-based measurement system provides automatic feedback
Identification of known and novel pancreas genes expressed downstream of Nkx2.2 during development
Keith R Anderson, Peter White, Klaus H Kaestner, Lori Sussel
BMC Developmental Biology , 2009, DOI: 10.1186/1471-213x-9-65
Abstract: Microarray analysis identified 80 genes that were differentially expressed in e12.5 and/or e13.5 Nkx2.2-/- embryos. Some of these genes encode transcription factors that have been previously identified in the pancreas, clarifying the position of Nkx2.2 within the islet transcriptional regulatory pathway. We also identified signaling factors and transmembrane proteins that function downstream of Nkx2.2, including several that have not previously been described in the pancreas. Interestingly, a number of known exocrine genes are also misexpressed in the Nkx2.2-/- pancreas.Expression profiling of Nkx2.2-/- mice during embryogenesis has allowed us to identify known and novel pancreatic genes that function downstream of Nkx2.2 to regulate pancreas development. Several of the newly identified signaling factors and transmembrane proteins may function to influence islet cell fate decisions. These studies have also revealed a novel function for Nkx2.2 in maintaining appropriate exocrine gene expression. Most importantly, Nkx2.2 appears to function within a complex regulatory loop with Ngn3 at a key endocrine differentiation step.The pancreas is a multifunctional organ that is critical for maintaining glucose homeostasis and for producing many of the enzymes required for digestion of carbohydrates, lipids and proteins. To carry out these diverse functions, the pancreas contains three major tissue types: the exocrine acinar cells, the endocrine cells that comprise the islet of Langerhans, and the ductal epithelial cells. Although each of these pancreatic components performs unique functions, all are derived from a defined set of endodermally-derived progenitors [1]. Subsequent pancreatic morphogenesis and differentiation of these progenitor populations is dependent on the concerted action of multiple transcriptional regulators. Early during pancreatic bud evagination, Pancreatic duodenal homeobox 1 (Pdx1) and Pancreatic transcription factor 1a (Ptf1a) are co-expressed in the p
Carbonyl sulfide exchange in a temperate loblolly pine forest grown under ambient and elevated CO2
M. L. White,Y. Zhou,R. S. Russo,H. Mao
Atmospheric Chemistry and Physics Discussions , 2009,
Abstract: Vegetation, soil and ecosystem level carbonyl sulfide (COS) exchange was observed at Duke Forest, a temperate loblolly pine forest, grown under ambient (Ring 1, R1) and elevated (Ring 2, R2) carbon dioxide (CO2). During calm meteorological conditions, ambient COS mixing ratios at the top of the forest canopy followed a distinct diurnal pattern in both CO2 growth regimes, with maximum COS mixing ratios during the day (R1=380±4 pptv and R2=373±3 pptv, daytime mean ±standard error) and minimums at night (R1=340±6 pptv and R2=346±5 pptv, nighttime mean ±standard error) reflecting a significant nighttime sink. Nocturnal vegetative uptake ( 11 to 21 pmol m 2 s 1, negative values indicate uptake from the atmosphere) dominated nighttime net ecosystem COS flux estimates ( 10 to 30 pmol m 2 s 1) in both CO2 regimes. In comparison, soil uptake ( 0.8 to 1.7 pmol m 2 s 1) was a minor component of net ecosystem COS flux. In both CO2 regimes, loblolly pine trees exhibited substantial COS consumption overnight (50% of daytime rates) that was independent of CO2 assimilation. This suggests current estimates of the global vegetative COS sink, which assume that COS and CO2 are consumed simultaneously, may need to be reevaluated. Ambient COS mixing ratios, species specific diurnal patterns of stomatal conductance, temperature and canopy position were the major factors influencing the vegetative COS flux at the branch level. While variability in branch level vegetative COS consumption measurements in ambient and enhanced CO2 environments could not be attributed to CO2 enrichment effects, estimates of net ecosystem COS flux based on ambient canopy mixing ratio measurements suggest less nighttime uptake of COS in R2, the CO2 enriched environment.
Multi-year (2004–2008) record of nonmethane hydrocarbons and halocarbons in New England: seasonal variations and regional sources
R. S. Russo,Y. Zhou,M. L. White,H. Mao
Atmospheric Chemistry and Physics Discussions , 2010,
Abstract: Multi-year time series records of C2-C6 alkanes, C2-C4 alkenes, ethyne, isoprene, C6-C8 aromatics, trichloroethene (C2HCl3), and tetrachloroethene (C2Cl4) from canister samples collected during January 2004–February 2008 at the University of New Hampshire (UNH) AIRMAP Observatory at Thompson Farm (TF) in Durham, NH are presented. The objectives of this work are to identify the sources of nonmethane hydrocarbons (NMHCs) and halocarbons observed at TF, characterize the seasonal and interannual variability in ambient mixing ratios and sources, and estimate regional emission rates of NMHCs. Analysis of correlations and comparisons with emission ratios indicated that a ubiquitous and persistent mix of emissions from several anthropogenic sources is observed throughout the entire year. The highest C2-C8 anthropogenic NMHC mixing ratios were observed in mid to late winter. Following the springtime minimums, the C3-C6 alkanes, C7-C8 aromatics, and C2HCl3 increased in early to mid summer, presumably reflecting enhanced evaporative emissions. Mixing ratios of C2Cl4 and C2HCl3 decreased by 0.7±0.2 and 0.3±0.05 pptv/year, respectively, which is indicative of reduced usage and emissions of these halogenated solvents. Emission rates of C3-C8 NMHCs were estimated to be 109 to 1010 molecules cm-2 s-1 in winter 2006. The emission rates extrapolated to the state of New Hampshire and New England were ~2–60 Mg/day and ~12–430 Mg/day, respectively. The 2002 and 2005 EPA National Emissions Inventory (NEI) emission rates of benzene, ethylbenzene, and xylenes for New Hampshire agreed within ±<5–20% of the emission rates estimated from the TF data, while toluene emissions were overestimated (20–35%) in both versions of the NEI.
Corrigendum to "Carbonyl sulfide exchange in a temperate loblolly pine forest grown under ambient and elevated CO2" published in Atmos. Chem. Phys., 10, 547–561, 2010
M. L. White,Y. Zhou,R. S. Russo,H. Mao
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2011, DOI: 10.5194/acp-11-12037-2011
Abstract: No abstract available.
Modeling the population dynamics of lemon sharks
Easton R White,John D Nagy,Samuel H Gruber
PeerJ , 2015, DOI: 10.7287/peerj.preprints.364v1
Abstract: Long-lived marine megavertebrates (e.g. sharks, turtles, mammals, and seabirds) are inherently vulnerable to anthropogenic mortality. Although some mathematical models have been applied successfully to manage these animals, more detailed treatments are often needed to assess potential drivers of population dynamics. In particular, factors such as age-structure, density-dependent feedbacks on reproduction, and demographic stochasticity are important for understanding population trends, but are often difficult to assess. Lemon sharks (Negaprion brevirostris) have a pelagic adult phase that makes them logistically difficult to study. However, juveniles use coastal nursery areas where their densities can be high. Thus, we use a stage-structured, Markov-chain stochastic model to describe lemon shark population dynamics from a 17-year longitudinal dataset at a coastal nursery area at Bimini, Bahamas. We found that the interaction between delayed breeding and demographic stochasticity accounts for 33 to 49% of the variance. Demographic stochasticity contributed all random effects in this model, suggesting that the existence of unmodeled environmental factors may be driving the majority of interannual population fluctuations. In addition, we are able to use our model to estimate the natural mortality rate of older age classes of lemon sharks that are difficult to study. Further, we use our model to examine what effect the length of a time series plays on deciphering ecological patterns. We find that — even with a relatively long time series — our sampling still misses important rare events. Our approach can be used more broadly to infer population dynamics of other large vertebrates in which age structure and demographic stochasticity are important.
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