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1

Elevated CO2 stimulates marsh elevation gain, counterbalancing sea-level rise  

USGS Publications Warehouse

Tidal wetlands experiencing increased rates of sea-level rise (SLR) must increase rates of soil elevation gain to avoid permanent conversion to open water. The maximal rate of SLR that these ecosystems can tolerate depends partly on mineral sediment deposition, but the accumulation of organic matter is equally important for many wetlands. Plant productivity drives organic matter dynamics and is sensitive to global change factors, such as rising atmospheric CO2 concentration. It remains unknown how global change will influence organic mechanisms that determine future tidal wetland viability. Here, we present experimental evidence that plant response to elevated atmospheric [CO2] stimulates biogenic mechanisms of elevation gain in a brackish marsh. Elevated CO2 (ambient 340 ppm) accelerated soil elevation gain by 3.9 mm yr1 in this 2-year field study, an effect mediated by stimulation of below-ground plant productivity. Further, a companion greenhouse experiment revealed that the CO2 effect was enhanced under salinity and flooding conditions likely to accompany future SLR. Our results indicate that by stimulating biogenic contributions to marsh elevation, increases in the greenhouse gas, CO2, may paradoxically aid some coastal wetlands in counterbalancing rising seas.

Langley, J.A.; McKee, K.L.; Cahoon, D.R.; Cherry, J.A.; Megonigala, J.P.

2009-01-01

2

Counter-balanced, multiple cable construction crane  

NASA Technical Reports Server (NTRS)

The invention is a counter-balanced, multiple cable construction crane. The apparatus for hoisting payloads comprises a crane having a lifting means, the lifting means comprising an end effector means and three suspension means or cables. One end of each cable attaches to a different winding means located on the lifting means, and the other end of each cable attaches to a different point on the end effector, such that the three cables have a theoretical point of convergence with this point corresponding to the center of mass of the payload. Three controls command rotation of the winding means to a predetermined position. Accordingly, the crane provides precise and autonomous positioning of the payload without human guidance. The crane further comprises a counter-balancing means. Two controls position the counter-balancing means to offset the overturning moment which arises during the lifting of heavy payloads.

Mikulas, Martin M., Jr. (inventor); Yang, Li-Farn (inventor)

1993-01-01

3

Counterbalancing for Serial Order Carryover Effects in Experimental Condition Orders  

ERIC Educational Resources Information Center

Reactions of neural, psychological, and social systems are rarely, if ever, independent of previous inputs and states. The potential for serial order carryover effects from one condition to the next in a sequence of experimental trials makes counterbalancing of condition order an essential part of experimental design. Here, a method is proposed…

Brooks, Joseph L.

2012-01-01

4

Optimizing Leaf Stomatal Conductance for Maximum Carbon Gain Under Salt Stressed and Elevated Atmospheric CO2 Conditions  

NASA Astrophysics Data System (ADS)

Understanding how plants adapt to different stresses such as droughts, hypoxic or hyper-saline conditions is necessary to progress on the broader problem of how carbon and water exchange rates between the biosphere and atmosphere react to a changing climate. In this work, the effects of increased salinity on photosynthesis, stomatal and mesophyll conductances under ambient and elevated atmospheric CO2 conditions are explored. A model based on stomatal optimization principles, according to which plants maximize carbon gain at a given water loss at the leaf scale, is generalized to include mesophyll conductance and its dependence on water salinity. The optimization problem is solved for both a non-linear and a linear biochemical demand function and both approaches are consistent with reported gas-exchange measurements in fresh water and in salt stressed conditions. It is shown here that an increase in salt stress causes an increase in the cost of water (and reduced stomatal conductance) for the plant as it does under water stress conditions. However, these reductions in photosynthetic rates observed under increased salt stress conditions cannot be attributed to limitation of CO2 diffusion alone since salt stress did reduce the photosynthetic capacity of plants by 30-40%.

Volpe, V.; Manzoni, S.; Marani, M.; Katul, G. G.

2011-12-01

5

Caffeine prevents weight gain and cognitive impairment caused by a high-fat diet while elevating hippocampal BDNF  

PubMed Central

Obesity, high-fat diets, and subsequent type 2 diabetes (T2DM) are associated with cognitive impairment. Moreover, T2DM increases the risk of Alzheimer’s disease (AD) and leads to abnormal elevation of brain beta-amyloid levels, one of the hallmarks of AD. The psychoactive alkaloid caffeine has been shown to have therapeutic potential in AD but the central impact of caffeine has not been well-studied in the context of a high-fat diet. Here we investigated the impact of caffeine administration on metabolism and cognitive performance, both in control rats and in rats placed on a high-fat diet. The effects of caffeine were significant: caffeine both (i) prevented the weight-gain associated with the high-fat diet and (ii) prevented cognitive impairment. Caffeine did not alter hippocampal metabolism or insulin signaling, likely because the high-fat-fed animals did not develop full-blown diabetes; however, caffeine did prevent or reverse a decrease in hippocampal brain-derived neurotrophic factor (BDNF) seen in high-fat-fed animals. These data confirm that caffeine may serve as a neuroprotective agent against cognitive impairment caused by obesity and/or a high-fat diet. Increased hippocampal BDNF following caffeine administration could explain, at least in part, the effects of caffeine on cognition and metabolism. PMID:23220362

Moy, Gregory A.; McNay, Ewan C.

2013-01-01

6

Carbon gain and bud physiology in Populus tremuloides and Betula papyrifera grown under long-term exposure to elevated concentrations of CO2 and O3.  

PubMed

Paper birch (Betula papyrifera Marsh.) and three trembling aspen clones (Populus tremuloides Michx.) were studied to determine if alterations in carbon gain in response to an elevated concentration of CO(2) ([CO(2)]) or O(3) ([O(3)]) or a combination of both affected bud size and carbohydrate composition in autumn, and early leaf development in the following spring. The trees were measured for gas exchange, leaf size, date of leaf abscission, size and biochemical characteristics of the overwintering buds and early leaf development during the 8th-9th year of free-air CO(2) and O(3) exposure at the Aspen FACE site located near Rhinelander, WI. Net photosynthesis was enhanced 49-73% by elevated [CO(2)], and decreased 13-30% by elevated [O(3)]. Elevated [CO(2)] delayed, and elevated [O(3)] tended to accelerate, leaf abscission in autumn. Elevated [CO(2)] increased the ratio of monosaccharides to di- and oligosaccharides in aspen buds, which may indicate a lag in cold acclimation. The total carbon concentration in overwintering buds was unaffected by the treatments, although elevated [O(3)] decreased the amount of starch by 16% in birch buds, and reduced the size of aspen buds, which may be related to the delayed leaf development in aspen during the spring. Elevated [CO(2)] generally ameliorated the effects of elevated [O(3)]. Our results show that both elevated [CO(2)] and elevated [O(3)] have the potential to alter carbon metabolism of overwintering buds. These changes may cause carry-over effects during the next growing season. PMID:18055435

Riikonen, Johanna; Kets, Katre; Darbah, Joseph; Oksanen, Elina; Sober, Anu; Vapaavuori, Elina; Kubiske, Mark E; Nelson, Neil; Karnosky, David F

2008-02-01

7

Do elevations in temperature, CO2, and nutrient availability modify belowground carbon gain and root morphology in artificially defoliated silver birch seedlings?  

PubMed Central

Climate warming increases the risk of insect defoliation in boreal forests. Losses in photosynthetically active surfaces cause reduction in net primary productivity and often compromise carbon reserves of trees. The concurrent effects of climate change and removal of foliage on root growth responses and carbohydrate dynamics are poorly understood, especially in tree seedlings. We investigated if exposures to different combinations of elevated temperature, CO2, and nutrient availability modify belowground carbon gain and root morphology in artificially defoliated 1-year-old silver birches (Betula pendula). We quantified nonstructural carbohydrates (insoluble starch as a storage compound; soluble sucrose, fructose, and glucose) singly and in combination in fine roots of plants under winter dormancy. Also the total mass, fine root proportion, water content, and length of roots were defined. We hypothesized that the measured properties are lower in defoliated birch seedlings that grow with ample resources than with scarce resources. On average, fertilization markedly decreased both the proportion and the carbohydrate concentrations of fine roots in all seedlings, whereas the effect of fertilization on root water content and dry mass was the opposite. However, defoliation mitigated the effect of fertilization on the root water content, as well as on the proportion of fine roots and their carbohydrate concentrations by reversing the outcomes. Elevation in temperature decreased and elevation in CO2 increased the absolute contents of total nonstructural carbohydrates, whereas fertilization alleviated both these effects. Also the root length and mass increased by CO2 elevation. This confirms that surplus carbon in birch tissues is used as a substrate for storage compounds and for cell wall synthesis. To conclude, our results indicate that some, but not all elements of climate change alter belowground carbon gain and root morphology in defoliated silver birch seedlings. PMID:24101972

Huttunen, Liisa; Saravesi, Karita; Markkola, Annamari; Niemelä, Pekka

2013-01-01

8

Elevated PDGFRB gene copy number gain is prognostic for improved survival outcomes in resected malignant pleural mesothelioma.  

PubMed

PDGF/PDGFR pathway has been implicated in malignant pleural mesothelioma (MPM) carcinogenesis, and evidence suggests autocrine mechanisms of proliferation. We sought to evaluate the incidence of PDGFRB gene copy number gain (CNG) by fluorescence in situ hybridization and PDGFR pathway protein expression by immunohistochemistry (IHC) and correlate it to patient clinical outcome. Eighty-eight archived tumor blocks from resected MPM with full clinical information were used to perform IHC biomarkers (PDGFR?, PDGFR?, p-PDGFR?) and fluorescence in situ hybridization analysis of PDGFRB gene CNG. Spearman rank correlation, Wilcoxon rank-sum test, Kruskal-Wallis test, BLiP plots, and Kaplan-Meier method were used to analyze the biomarkers and correlation to clinical outcome. Several correlations between the IHC biomarkers were seen; however, none correlated to clinically relevant patient demographics or histology. In the CNG analysis, PDGFRB gene CNG in >10% of tumor cells had lower cytoplasmic p-PDGFR? (P=.029), while PDGFRB gene CNG in >40% of tumor cells had a higher cytoplasmic PDGFR? (P=.04). PDGFRB gene CNG status did not associate with patient demographics or tumor characteristics. PDGFR pathway IHC biomarkers did not associate with survival outcomes. However, patients with PDGFRB CNG >40% of tumor cells had improved relapse-free survival (HR 0.25 [95% CI 0.09-0.72], P=.0096) and improved overall survival (HR 0.32 [95% CI 0.11-0.89], P=.029). PDGFRB CNG >40% of MPM tumor cells is a potential prognostic biomarker for surgery and may identify a unique population of mesothelioma patients. Future validation of this biomarker in prospective trials is needed. From a retrospective review of archived tissue specimens from patients with resected malignant pleural mesothelioma tumors, we show that patients with PDGFRB CNG >40% of tumor cells had improved relapse-free survival (HR 0.25 [95% CI 0.09-0.72], P=.0096) and improved overall survival (HR 0.32 [95% CI 0.11-0.89], P=.029). PDGFRB CNG >40% of MPM tumor cells is a potential prognostic biomarker for surgery and may identify a unique population of mesothelioma patients. PMID:24747001

Tsao, Anne S; Harun, Nusrat; Fujimoto, Junya; Devito, Vikki; Lee, J Jack; Kuhn, Elisabetta; Mehran, Reza; Rice, David; Moran, Cesar; Hong, Waun Ki; Shen, Li; Suraokar, Milind; Wistuba, Ignacio

2014-06-01

9

Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force on core  

E-print Network

Core-annular flow through a horizontal pipe: Hydrodynamic counterbalancing of buoyancy force; published online 28 September 2007 A theoretical investigation has been made of core-annular flow: the flow of a high-viscosity liquid core surrounded by a low-viscosity liquid annular layer through a horizontal pipe

Vuik, Kees

10

Gaso-dynamic counterbalancer for pneumatically driven expander in rotary split Stirling cryocooler  

NASA Astrophysics Data System (ADS)

Numerous military thermal imagers operating under hostile environmental conditions rely on tactical rotary split Stirling cryocoolers, the pneumatically driven expanders of which are known to be the source of considerable vibration export. The cold tip temperature in such a cooler is typically stabilized by controlling the driving frequency in accordance with thermal loading and ambient temperature, leading to a frequency-swept harmonic vibration export into the optomechanical structure of the thermal imager. The active vibration cancellation systems are basically capable of suppressing such vibration, but are still quite bulky, complicated and expensive. In this paper, the authors report on the recent efforts towards developing a low cost vibration counterbalancer for a pneumatically driven expander in a rotary cryogenic cooler. In this approach, the flexurally suspended auxiliary mass - counterbalancer - is arranged to oscillate coaxially with the expander"s displacer and is driven pneumatically by the pulses of the working fluid produced by the compressor. Based on the results of analytical modeling and Sage optimization, the counterbalancer was designed and manufactured as an integral part of such an expander. The full-scale experimentation has shown essential cancellation of vibration export within the working frequency range from 30 to 60Hz without noticeable effect on cryocooler performance.

Riabzev, Sergey V.; Veprik, Alexander M.; Pundak, Nachman; Pratt, Uri; Vilenchik, Herman

2004-08-01

11

A contractile and counterbalancing adhesion system controls the 3D shape of crawling cells  

PubMed Central

How adherent and contractile systems coordinate to promote cell shape changes is unclear. Here, we define a counterbalanced adhesion/contraction model for cell shape control. Live-cell microscopy data showed a crucial role for a contractile meshwork at the top of the cell, which is composed of actin arcs and myosin IIA filaments. The contractile actin meshwork is organized like muscle sarcomeres, with repeating myosin II filaments separated by the actin bundling protein ?-actinin, and is mechanically coupled to noncontractile dorsal actin fibers that run from top to bottom in the cell. When the meshwork contracts, it pulls the dorsal fibers away from the substrate. This pulling force is counterbalanced by the dorsal fibers’ attachment to focal adhesions, causing the fibers to bend downward and flattening the cell. This model is likely to be relevant for understanding how cells configure themselves to complex surfaces, protrude into tight spaces, and generate three-dimensional forces on the growth substrate under both healthy and diseased conditions. PMID:24711500

Burnette, Dylan T.; Shao, Lin; Ott, Carolyn; Pasapera, Ana M.; Fischer, Robert S.; Baird, Michelle A.; Der Loughian, Christelle; Delanoe-Ayari, Helene; Paszek, Matthew J.; Davidson, Michael W.; Betzig, Eric

2014-01-01

12

Elevating your elevator talk  

Technology Transfer Automated Retrieval System (TEKTRAN)

An important and often overlooked item that every early career researcher needs to do is compose an elevator talk. The elevator talk, named because the talk should not last longer than an average elevator ride (30 to 60 seconds), is an effective method to present your research and yourself in a clea...

13

Microbe-driven turnover offsets mineral-mediated storage of soil carbon under elevated CO2  

NASA Astrophysics Data System (ADS)

The sensitivity of soil organic carbon (SOC) to changing environmental conditions represents a critical uncertainty in coupled carbon cycle-climate models. Much of this uncertainty arises from our limited understanding of the extent to which root-microbe interactions induce SOC losses (through accelerated decomposition or `priming') or indirectly promote SOC gains (via `protection' through interactions with mineral particles). We developed a new SOC model to examine priming and protection responses to rising atmospheric CO2. The model captured disparate SOC responses at two temperate free-air CO2 enrichment (FACE) experiments. We show that stabilization of `new' carbon in protected SOC pools may equal or exceed microbial priming of `old' SOC in ecosystems with readily decomposable litter and high clay content (for example, Oak Ridge). In contrast, carbon losses induced through priming dominate the net SOC response in ecosystems with more resistant litters and lower clay content (for example, Duke). The SOC model was fully integrated into a global terrestrial carbon cycle model to run global simulations of elevated CO2 effects. Although protected carbon provides an important constraint on priming effects, priming nonetheless reduced SOC storage in the majority of terrestrial areas, partially counterbalancing SOC gains from enhanced ecosystem productivity.

Sulman, Benjamin N.; Phillips, Richard P.; Oishi, A. Christopher; Shevliakova, Elena; Pacala, Stephen W.

2014-12-01

14

Development of an indirect counterbalanced pendulum optical-lever thrust balance for micro- to millinewton thrust measurement  

NASA Astrophysics Data System (ADS)

This paper describes the design and testing of an indirect hanging pendulum thrust balance using a laser-optical-lever principle to provide micro- to millinewton thrust measurement for the development of electric propulsion systems. The design philosophy allows the selection of the total thrust range in order to maximize resolution through a counterbalanced pendulum principle, as well as passive magnetic damping in order to allow relatively rapid transient thrust measurement. The balance was designed for the purpose of hollow cathode microthruster characterization, but could be applied to other electric propulsion devices in the thrust range of micro- to millinewtons. An initial thrust characterization of the T5 hollow cathode is presented.

Grubiši?, A. N.; Gabriel, S. B.

2010-10-01

15

Assessing the impact of user-centered research on a clinical trial eHealth tool via counterbalanced research design  

PubMed Central

Objective Informatics applications have the potential to improve participation in clinical trials, but their design must be based on user-centered research. This research used a fully counterbalanced experimental design to investigate the effect of changes made to the original version of a website, http://BreastCancerTrials.org/, and confirm that the revised version addressed and reinforced patients' needs and expectations. Design Participants included women who had received a breast cancer diagnosis within the last 5?years (N=77). They were randomized into two groups: one group used and reviewed the original version first followed by the redesigned version, and the other group used and reviewed them in reverse order. Measurements The study used both quantitative and qualitative measures. During use, participants' click paths and general reactions were observed. After use, participants were asked to answer survey items and open-ended questions to indicate their reactions and which version they preferred and met their needs and expectations better. Results Overall, the revised version of the site was preferred and perceived to be clearer, easier to navigate, more trustworthy and credible, and more private and safe overall. However, users who viewed the original version last had similar attitudes toward both versions. Conclusion By applying research findings to the redesign of a website for clinical trial searching, it was possible to re-engineer the interface to better support patients' decisions to participate in clinical trials. The mechanisms of action in this case appeared to revolve around creating an environment that supported a sense of personal control and decisional autonomy. PMID:21169619

Massett, Holly A; Mylks, Christy; McCormack, Lauren A; Kish-Doto, Julia; Hesse, Bradford W; Wang, Min Qi

2010-01-01

16

Weight Gain during Pregnancy  

MedlinePLUS

... this page It's been added to your dashboard . Weight gain during pregnancy When you’re pregnant, you ... in sight! Be careful about the amount of weight you gain during your pregnancy. Gaining too much ...

17

IR gain monitor  

NASA Astrophysics Data System (ADS)

The gain of the IR channel of WFC3 will be measured using a series of internal flat fields. Using knowledge gained from ground testing and previous cycles, we propose to collect flat field ramps which will be used to create photon transfer curves and give a measure of the gain. This continues the strategy of last cycle's gain monitor, in proposal 13080.

Hilbert, Bryan

2013-10-01

18

Optical automatic gain channel  

NASA Technical Reports Server (NTRS)

Automatic Gain Control /AGC/ channel automatically compensates for gain changes in the azimuth error channel due to time varying optical sight degrading effects. This system is useful in remote television monitors, automatic navigation systems, and surveying and mapping instrumentation.

Mrus, G.; Zukowsky, W.

1966-01-01

19

Alpha-2 adrenoceptors and imidazoline receptors in cardiomyocytes mediate counterbalancing effect of agmatine on NO synthesis and intracellular calcium handling.  

PubMed

Evidence suggests that intracellular Ca(2+) levels and contractility of cardiomyocytes can be modulated by targeting receptors other than already identified adrenergic or non-adrenergic sarcolemmal receptors. This study uncovers the presence in myocardial cells of adrenergic ?2 (?2-AR) and imidazoline I1 (I1R) receptors. In isolated left ventricular myocytes generating stationary spontaneous Ca(2+) transients in the absence of triggered action potentials, the prototypic agonist of both receptors agmatine can activate corresponding signaling cascades with opposing outcomes on nitric oxide (NO) synthesis and intracellular Ca(2+) handling. Specifically, activation of ?2-AR signaling through PI3 kinase and Akt/protein kinase B stimulates NO production and abolishes Ca(2+) transients, while targeting of I1R signaling via phosphatidylcholine-specific phospholipase C (PC-PLC) and protein kinase C (PKC) suppresses NO synthesis and elevates averaged intracellular Ca(2+). We identified that endothelial NO synthase (eNOS) is a major effector for both signaling cascades. According to the established eNOS transitions between active (Akt-dependent) and inactive (PKC-dependent) conformations, we suggest that balance between ?2-AR and I1R signaling pathways sets eNOS activity, which by defining operational states of myocellular sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) can adjust Ca(2+) re-uptake and thereby cardiac inotropy. These results indicate that the conventional catalog of cardiomyocyte sarcolemmal receptors should be expanded by the ?2-AR and I1R populations, unveiling previously unrecognized targets for endogenous ligands as well as for existing and potential pharmacological agents in cardiovascular medicine. PMID:24412533

Maltsev, Alexander V; Kokoz, Yuri M; Evdokimovskii, Edward V; Pimenov, Oleg Y; Reyes, Santiago; Alekseev, Alexey E

2014-03-01

20

Optimal Weight Gain  

Microsoft Academic Search

Optimal birth weight and outcome are influenced by maternal weight gain. Low gestational weight gain is associated with poor\\u000a fetal growth and risk of preterm delivery. Excessive weight gain affects infant growth, body fatness in childhood, and the\\u000a potential for postpartum weight retention and future obesity. Guidelines from the Institute of Medicine recommend that a woman\\u000a with a normal body

Grace A. Falciglia; Kristin H. Coppage

21

Nutrition During Weight Gain  

E-print Network

, Department of Food Science and Human Nutrition, 3/09 MSU is an affirmative-action, equal-opportunity employerNutrition During Pregnancy Weight Gain: The right weight gain (not too little and not too much you are taking, such as vitamins, minerals or herbs. Nutrition during pregnancy is very important

22

Comparing gains and losses.  

PubMed

Loss aversion in choice is commonly assumed to arise from the anticipation that losses have a greater effect on feelings than gains, but evidence for this assumption in research on judged feelings is mixed. We argue that loss aversion is present in judged feelings when people compare gains and losses and assess them on a common scale. But many situations in which people judge and express their feelings lack these features. When judging their feelings about an outcome, people naturally consider a context of similar outcomes for comparison (e.g., they consider losses against other losses). This process permits gains and losses to be normed separately and produces psychological scale units that may not be the same in size or meaning for gains and losses. Our experiments show loss aversion in judged feelings for tasks that encourage gain-loss comparisons, but not tasks that discourage them, particularly those using bipolar scales. PMID:20739673

McGraw, A Peter; Larsen, Jeff T; Kahneman, Daniel; Schkade, David

2010-10-01

23

Hormonal treatment increases the response of the reward system at the menopause transition: A counterbalanced randomized placebo-controlled fMRI study.  

PubMed

Preclinical research using rodent models demonstrated that estrogens play neuroprotective effects if they are administered during a critical period near the time of cessation of ovarian function. In women, a number of controversial epidemiological studies reported that a neuroprotective effect of estradiol may be obtained on cognition and mood-related disorders if hormone therapy (HT) begins early at the beginning of menopause. Yet, little is known about the modulatory effects of early HT administration on brain activation near menopause. Here, we investigated whether HT, initiated early during the menopause transition, increases the response of the reward system, a key brain circuit involved in motivation and hedonic behavior. We used fMRI and a counterbalanced, double-blind, randomized and crossover placebo-controlled design to investigate whether sequential 17?-estradiol plus oral progesterone modulate reward-related brain activity. Each woman was scanned twice while presented with images of slot machines, once after receiving HT and once under placebo. The fMRI results demonstrate that HT, relative to placebo, increased the response of the striatum and ventromedial prefrontal cortex, two areas that have been shown to be respectively involved during reward anticipation and at the time of reward delivery. Our neuroimaging results bridge the gap between animal studies and human epidemiological studies of HT on cognition. These findings establish a neurobiological foundation for understanding the neurofunctional impact of early HT initiation on reward processing at the menopause transition. PMID:25222702

Thomas, Julie; Météreau, Elise; Déchaud, Henri; Pugeat, Michel; Dreher, Jean-Claude

2014-12-01

24

VECSEL gain characterization.  

PubMed

We present the first full gain characterization of two vertical external cavity surface emitting laser (VECSEL) gain chips with similar designs operating in the 960-nm wavelength regime. We optically pump the structures with continuous-wave (cw) 808-nm radiation and measure the nonlinear reflectivity for 130-fs and 1.4-ps probe pulses as function of probe pulse fluence, pump power, and heat sink temperature. With this technique we are able to measure the saturation behavior for VECSEL gain chips for the first time. The characterization with 1.4-ps pulses resulted in saturation fluences of 40-80 ?J/cm2, while probing with 130-fs pulses yields reduced saturation fluences of 30-50 ?J/cm2 for both structures. For both pulse durations this is lower than previously assumed. A small-signal gain of up to 5% is obtained with this technique. Furthermore, in a second measurement setup, we characterize the spectral dependence of the gain using a tunable cw probe beam. We measure a gain bandwidth of over 26 nm for both structures, full width at half maximum. PMID:22418171

Mangold, Mario; Wittwer, Valentin J; Sieber, Oliver D; Hoffmann, Martin; Krestnikov, Igor L; Livshits, Daniil A; Golling, Matthias; Südmeyer, Thomas; Keller, Ursula

2012-02-13

25

USGS Elevation Monument  

USGS Multimedia Gallery

USGS elevation monument for a level line run from Mojave, California to Keeler, California. The line ran through such places as 18-Mile Station, Dixie, Indan Wells, Little Lake, and Olancha. Elevations were based on Benecia datum....

26

Configuring elevator systems  

Microsoft Academic Search

To configure an elevator system, one must assemble a collection of components that satisfies both customer demands and safety regulations. Complex interactions among elevator system components complicate the configuration process. Not all components are compatible, and certain combinations will not meet functional or safety requirements. This document describes how a configuration engineer configures elevator systems. It describes what initial information

Gregg R. Yost; Thomas R. Rothenfluh

1996-01-01

27

No evidence of dehydration with moderate daily coffee intake: a counterbalanced cross-over study in a free-living population.  

PubMed

It is often suggested that coffee causes dehydration and its consumption should be avoided or significantly reduced to maintain fluid balance. The aim of this study was to directly compare the effects of coffee consumption against water ingestion across a range of validated hydration assessment techniques. In a counterbalanced cross-over design, 50 male coffee drinkers (habitually consuming 3-6 cups per day) participated in two trials, each lasting three consecutive days. In addition to controlled physical activity, food and fluid intake, participants consumed either 4×200 mL of coffee containing 4 mg/kg caffeine (C) or water (W). Total body water (TBW) was calculated pre- and post-trial via ingestion of Deuterium Oxide. Urinary and haematological hydration markers were recorded daily in addition to nude body mass measurement (BM). Plasma was analysed for caffeine to confirm compliance. There were no significant changes in TBW from beginning to end of either trial and no differences between trials (51.5±1.4 vs. 51.4±1.3 kg, for C and W, respectively). No differences were observed between trials across any haematological markers or in 24 h urine volume (2409±660 vs. 2428±669 mL, for C and W, respectively), USG, osmolality or creatinine. Mean urinary Na(+) excretion was higher in C than W (p?=?0.02). No significant differences in BM were found between conditions, although a small progressive daily fall was observed within both trials (0.4±0.5 kg; p<0.05). Our data show that there were no significant differences across a wide range of haematological and urinary markers of hydration status between trials. These data suggest that coffee, when consumed in moderation by caffeine habituated males provides similar hydrating qualities to water. PMID:24416202

Killer, Sophie C; Blannin, Andrew K; Jeukendrup, Asker E

2014-01-01

28

No Evidence of Dehydration with Moderate Daily Coffee Intake: A Counterbalanced Cross-Over Study in a Free-Living Population  

PubMed Central

It is often suggested that coffee causes dehydration and its consumption should be avoided or significantly reduced to maintain fluid balance. The aim of this study was to directly compare the effects of coffee consumption against water ingestion across a range of validated hydration assessment techniques. In a counterbalanced cross-over design, 50 male coffee drinkers (habitually consuming 3–6 cups per day) participated in two trials, each lasting three consecutive days. In addition to controlled physical activity, food and fluid intake, participants consumed either 4×200 mL of coffee containing 4 mg/kg caffeine (C) or water (W). Total body water (TBW) was calculated pre- and post-trial via ingestion of Deuterium Oxide. Urinary and haematological hydration markers were recorded daily in addition to nude body mass measurement (BM). Plasma was analysed for caffeine to confirm compliance. There were no significant changes in TBW from beginning to end of either trial and no differences between trials (51.5±1.4 vs. 51.4±1.3 kg, for C and W, respectively). No differences were observed between trials across any haematological markers or in 24 h urine volume (2409±660 vs. 2428±669 mL, for C and W, respectively), USG, osmolality or creatinine. Mean urinary Na+ excretion was higher in C than W (p?=?0.02). No significant differences in BM were found between conditions, although a small progressive daily fall was observed within both trials (0.4±0.5 kg; p<0.05). Our data show that there were no significant differences across a wide range of haematological and urinary markers of hydration status between trials. These data suggest that coffee, when consumed in moderation by caffeine habituated males provides similar hydrating qualities to water. PMID:24416202

Killer, Sophie C.; Blannin, Andrew K.; Jeukendrup, Asker E.

2014-01-01

29

A CpG-containing oligodeoxynucleotide as an efficient adjuvant counterbalancing the Th1/Th2 immune response in diphtheria-tetanus-pertussis vaccine.  

PubMed

Adjuvants in vaccines are immune stimulants that play an important role in the induction of effective and appropriate immune responses to vaccine component(s). Diphtheria-tetanus-pertussis (DPT) vaccine contains not only aluminum hydrate (alum) to enhance the immune response to the vaccine ingredients, but also, both for that purpose and as a principal ingredient, pertussis toxin (PT). However, both adjuvants strongly promote T helper (Th) 2 type immune responses. Th1 and Th2 type immune responses are counterbalanced in vivo, and a Th2-prone immune response is not effective against intracellular infections but promotes IgE production, which is related to allergic disease. In this study, we used the CpG motif contained in oligodeoxynucleotide (CpG-ODN), which has an adjuvant effect and also induces the Th1 response, as an adjuvant to this vaccine, and we investigated its adjuvanticity and its potential to modulate immune responses to DPT vaccine. Administration of DPT vaccine with CpG-ODN (DPT-alum/ODN) to mice significantly reduced the total IgE levels and increased the anti-PT specific IgG2a titer in serum, in comparison with ordinary DPT vaccine (DPT-alum). Moreover, we investigated the antibody response to orally administrated ovalbumin (OVA) after vaccine administration. In the DPT-alum/ODN-administered group, the OVA specific IgE production in serum greatly decreased in comparison with that in the DPT-alum-administered group. These data indicate that CpG-ODN was not useful only as an efficient vaccine adjuvant but also shifted the immune responses substantially toward Th1 and modulated the Th1/Th2 immune response in DPT vaccine. These data suggested new applications of CpG-ODN as adjuvants in DPT vaccine. PMID:16006019

Sugai, Toshiyuki; Mori, Masaaki; Nakazawa, Masatoshi; Ichino, Motohide; Naruto, Takuya; Kobayashi, Naoki; Kobayashi, Yoshinori; Minami, Mutsuhiko; Yokota, Shumpei

2005-11-16

30

Receiver Gain Modulation Circuit  

NASA Technical Reports Server (NTRS)

A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by modulating the receiver gain using an external signal. Without the RGMC, samples of calibrated references from radiometers form an ensemble data set of the natural occurring fluctuations within a receiver. By driving the gain of an otherwise stable receiver with an external signal, the conceptual framework and generalization of the mathematics of EDA can be tested. A series of measurements was conducted to evaluate and characterize the performance of the RGMC. Test signals stepped the RGMC across its dynamic range of performance using a radiometer that sampled four noise references; analysis indicates that the RGMC successfully modulated the receiver gain with an external signal. Calibration algorithms applied to four noise references demonstrate the RGMC produced ensemble data sets of the external signal.

Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

2011-01-01

31

Effect of Tolcapone on Brain Activity During a Variable Attentional Control Task: A Double-Blind, Placebo-Controlled, Counter-Balanced Trial in Healthy Volunteers  

PubMed Central

Background Attention is the capacity to flexibly orient behaviors and thoughts towards a goal by selecting and integrating relevant contextual information. The dorsal cingulate (dCC) and prefrontal (PFC) cortices play critical roles in attention. Evidence indicates that catechol-O-methyltransferase (COMT) modulates dopaminergic tone in the PFC and dCC. Objective In this study, we explored the effect of tolcapone, a CNS penetrant COMT inhibitor that increases cortical dopamine levels, on brain activity during a Variable Attentional Control (VAC) task. Study Design We performed a double-blinded, placebo-controlled, counter-balanced trial with tolcapone (Tasmar, tablets, 100 mg three times a day for 1 day and then 200 mg three times a day for 6 days; ClinicalTrials.gov identifier: NCT00044083). Setting The study was conducted in the Clinical Center of the National Institute of Mental Health from 2005 to 2009. Patients Twenty healthy volunteers (11 males; mean age = 32.7 years) with good imaging and performance data on both arms of the study were investigated. Intervention Participants underwent 3T blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) while performing the event-related VAC task, which varies attention over three levels of load: LOW, INT (intermediate), and HIGH. Main Outcome Measure Changes in behavioral data and individual contrast images were analyzed using ANOVA with drug and task load as co-factors. Results There was a significant main effect of increasing task load, with resulting decreased accuracy and increased reaction time. While there was no significant effect of tolcapone on these behavioral measures, the neuroimaging data showed a significant effect on load-related changes in dCC, with significantly lower dCC activation on tolcapone compared with placebo. Further, neural activity in dCC correlated positively with COMT enzyme activity (i.e., lower COMT activity and presumably more dopamine was associated with lower activation in dCC, i.e., more efficient information processing). Conclusion Our results show that pharmacological reduction of COMT activity modulates the engagement of attentional mechanisms, selectively enhancing the efficiency of dCC processing in healthy volunteers, reflected as decreased activity for the same level of performance. PMID:23794107

Magalona, Sophia C.; Rasetti, Roberta; Chen, Jingshan; Chen, Qiang; Gold, Ian; Decot, Heather; Callicott, Joseph H.; Berman, Karen F.; Apud, José A.; Weinberger, Daniel R.

2014-01-01

32

Smoking Cessation and Weight Gain.  

ERIC Educational Resources Information Center

Investigated determinants of weight gain after quitting smoking in two smoking treatment outcome studies. Results indicated abstinence resulted in weight gain, and postquitting weight gain was predicted by pretreatment tobacco use, a history of weight problems, and eating patterns. Relapse to smoking did not follow weight gain. (Author/BL)

Hall, Sharon M.; And Others

1986-01-01

33

NATIONAL ELEVATION DATASET HILLSHADE  

EPA Science Inventory

The USGS National Elevation Dataset (NED) has been developed bymerging the highest-resolution, best-quality elevation data available across the United States into a seamless raster format. NED is the result of the maturation of the USGS effort to provide 1:24,000-scale Digital E...

34

NATIONAL ELEVATION DATASET  

EPA Science Inventory

The USGS National Elevation Dataset (NED) has been developed by merging the highest-resolution, best-quality elevation data available across the United States into a seamless raster format. NED is the result of the maturation of the USGS effort to provide 1:24,000-scale Digital ...

35

Helicopter high gain control  

NASA Technical Reports Server (NTRS)

High gain control is explored through a design study of the CH-47B helicopter. The plans are designed to obtain the maximum bandwidth possible given the hardware constraints. Controls are designed with modal control theory to specific bandwidths and closed loop mode shapes. Comparisons are made to an earlier complementary filter approach. Bandwidth improvement by removal of limitations is explored in order to establish hardware and mechanization options. Improvements in the pitch axis control system and in the rate gyro sensor noise characteristics in all axes are discussed. The use of rotor state feedback is assessed.

Cunningham, T. B.; Nunn, E. C.

1979-01-01

36

Introduction to Grain Elevators  

NSDL National Science Digital Library

The US Department of Agriculture has placed online this series of presentations on grain elevators. The presentations (VRML 2.0) demonstrate "the operation of an export elevator; the operation of a bulkweighing scale and the procedure for performing a build-up scale test; a description of electronic control systems; a 3-dimensional model of a shipping bin and diverter gates; and a simulation of a gate limit switch test." Demos include animated color images with fully labeled parts and summary paragraphs. From agricultural students to design engineers, as well as those who have always wanted to know, visitors will obtain a solid introduction to grain elevators from this informative resource.

1998-01-01

37

A Nanotube Space Elevator  

NSDL National Science Digital Library

In this video adapted from NOVA scienceNOW, find out about the discovery of a new building material, the carbon nanotube, whose physical properties could theoretically enable the creation of a 22,000-mile elevator to space.

WGBH Educational Foundation

2008-09-08

38

Light: Isometric Casing with Lens, South Elevation, North Elevation, Top ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Light: Isometric Casing with Lens, South Elevation, North Elevation, Top Plan, Base Plan; Fresnel Lens: Isometric, Elevation, Plan - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD

39

Weight Gain Prevention among Women  

Microsoft Academic Search

Objective: Women 25 to 45 years old are at risk for weight gain and future obesity. This trial was designed to evaluate the efficacy of two interventions relative to a control group in preventing weight gain among normal or overweight women and to identify demographic, behavioral, and psychosocial factors related to weight gain prevention.Research Methods and Procedures: Healthy women (N

Michele D. Levine; Mary Lou Klem; Melissa A. Kalarchian; Rena R. Wing; Lisa Weissfeld; Li Qin; Marsha D. Marcus

2007-01-01

40

Elevate America's State Voucher Strategy  

E-print Network

the first Elevate America offering--a partnership with state governments to provide computer skills trainElevate America's State Voucher Strategy to Promote Employability Lessons Learned April 2011 #12 ...............................................................................................................................15 Additional information about Elevate America is available at: http

Bernstein, Phil

41

Acting to gain information  

NASA Technical Reports Server (NTRS)

This report is concerned with agents that act to gain information. In previous work, we developed agent models combining qualitative modeling with real-time control. That work, however, focused primarily on actions that affect physical states of the environment. The current study extends that work by explicitly considering problems of active information-gathering and by exploring specialized aspects of information-gathering in computational perception, learning, and language. In our theoretical investigations, we analyzed agents into their perceptual and action components and identified these with elements of a state-machine model of control. The mathematical properties of each was developed in isolation and interactions were then studied. We considered the complexity dimension and the uncertainty dimension and related these to intelligent-agent design issues. We also explored active information gathering in visual processing. Working within the active vision paradigm, we developed a concept of 'minimal meaningful measurements' suitable for demand-driven vision. We then developed and tested an architecture for ongoing recognition and interpretation of visual information. In the area of information gathering through learning, we explored techniques for coping with combinatorial complexity. We also explored information gathering through explicit linguistic action by considering the nature of conversational rules, coordination, and situated communication behavior.

Rosenchein, Stanley J.; Burns, J. Brian; Chapman, David; Kaelbling, Leslie P.; Kahn, Philip; Nishihara, H. Keith; Turk, Matthew

1993-01-01

42

Elevation Differences on Mars  

Microsoft Academic Search

Observations of apparent frost phenomena, occurring preferentially in the Martian bright areas, have in the past led to. the conclusion that the bright areas are elevations. The argument hinges on the implicit assumption that, near midday, highlands should be at lower temperatures than lowlands. On the earth, this assumption is valid, because of adiabatic cooling of rising air, a diminished

Carl Sagan; James B. Pollack

1968-01-01

43

Gain-Scheduled Control: Relaxing Slow Variation Requirements by Velocity-Based Douglas J. Leith  

E-print Network

@icu.strath.ac.uk 2 The effective elevator deflection, , may represent the combined action of several control surfacesGain-Scheduled Control: Relaxing Slow Variation Requirements by Velocity-Based Design Douglas J of the gain-scheduling approach to flight control tasks where the conditions required by conventional

Duffy, Ken

44

Mechanisms of the Rosetta high gain antenna  

NASA Astrophysics Data System (ADS)

This paper describes the antenna pointing mechanism (APM) and the hold down and release mechanism (HRM) used in the high gain antenna of the ROSETTA mission. The hold down and release mechanism consists of three units which compensate the tolerance mismatch between antenna and spacecraft through incorporation of potting rings. Given that the activation mode is pyrotechnic, release shock is a major concern and is minimised through integration of shock absorbers which allow stroking of the separation nuts. The antenna pointing mechanism is a dual drive (azimuth over elevation) unit which allows controlled rotation of the antenna. The drive units incorporate spring loaded end stops to prevent the antenna from hitting the spacecraft, and optical encoders which register the absolute position of the antenna. The pointing and the hold down mechanisms of the ROSETTA antenna are fully qualified and will withstand the high launch loads of the Ariane-5 and the environmental demands of deep space operation.

Pereira, Carlos

2001-09-01

45

Elevated temperature crack growth  

NASA Technical Reports Server (NTRS)

The objective of the Elevated Temperature Crack Growth Project is to evaluate proposed nonlinear fracture mechanics methods for application to combustor liners of aircraft gas turbine engines. During the first year of this program, proposed path-independent (P-I) integrals were reviewed for such applications. Several P-I integrals were implemented into a finite-element postprocessor which was developed and verified as part of the work. Alloy 718 was selected as the analog material for use in the forthcoming experimental work. A buttonhead, single-edge notch specimen was designed and verified for use in elevated-temperature strain control testing with significant inelastic strains. A crack mouth opening displacement measurement device was developed for further use.

Yau, J. F.; Malik, S. N.; Kim, K. S.; Vanstone, R. H.; Laflen, J. H.

1985-01-01

46

LOW-ELEVATION NESTING BY CALLIOPE HUMMINGBIRDS IN THE WESTERN  

Microsoft Academic Search

The Calliope Hummingbird breeds uncommonly to fairly commonly in the Sierra Nevada and other high mountain ranges in California. In the Sierra it typically nests above 4000 feet elevation (Grinnell and Miller 1944, Gaines 1992, pers. obs.), usually near moist meadows or other relatively level and wet sites with a mixture of deciduous and coniferous trees, shrubs, and flowering plants

2001-01-01

47

Elevated temperature crack growth  

NASA Technical Reports Server (NTRS)

The objective of the Elevated Temperature Crack Growth Program is to evaluate proposed nonlinear fracture mechanics methods for application to hot section components of aircraft gas turbine engines. Progress during the past year included linear-elastic fracture mechanics data reduction on nonlinear crack growth rate data on Alloy 718. The bulk of the analytical work centered on thermal gradient problems and proposed fracture mechanics parameters. Good correlation of thermal gradient experimental displacement data and finite element prediction was obtained.

Malik, S. N.; Vanstone, R. H.; Kim, K. S.; Laflen, J. H.

1987-01-01

48

VIEW SOUTHWEST, EAST GABLE ELEVATIONS AND NORTH ELEVATIONS OF ENGINE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW SOUTHWEST, EAST GABLE ELEVATIONS AND NORTH ELEVATIONS OF ENGINE HOUSE IN FOREGROUND AND ECCENTRIC HOUSE IN REAR NOTE ROD LINES IN FOREGROUND RIGHT. - Golden Oil Company, Lot 410 Lease, Sheffield Field, Donaldson, Warren County, PA

49

3. A general elevation view looking west highlights the Elevator ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. A general elevation view looking west highlights the Elevator and Silo Complex C, commonly known as the 'Landmark' (1940). - Quaker Oats Cereal Factory, Southeast corner of Broadway & Mill Streets, Akron, Summit County, OH

50

33. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), Fuel Storage Bins (center), and Power Plant (right) Photographs taken by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

51

Modal Analysis and Gain Estimation  

NASA Technical Reports Server (NTRS)

Interactive program yields eigenvectors, eigenvalues, and gains for feedback-control systems. Interactive Modal Analysis and Gain Estimation System (IMAGES) provides eigensystem synthesis capability to control-system engineer. IMAGES modular and flexible. Capable of both modal and spectral synthesis of multi-input control systems. IMAGES user-oriented, interactive program that frees engineer to concentrate on eigensystem synthesis. Engineer provided with scratch-pad capability that speeds control-system design.

Jones, R. L.

1986-01-01

52

Digital Elevation Models  

USGS Publications Warehouse

The Earth Science Information Center (ESIC) distributes digital cartographic/geographic data files produced by the U.S. Geological Survey (USGS) as part of the National Mapping Program. Digital cartographic data files may be grouped into four basic types. The first of these, called a Digital Line Graph (DLG), is the line map information in digital form. These data files include information on base data categories, such as transportation, hypsography, hydrography, and boundaries. The second type, called a Digital Elevation Model (DEM), consists of a sampled array of elevations for a number of ground positions at regularly spaced intervals. The third type is Land Use and Land Cover digital data which provides information on nine major classes of land use such as urban, agricultural, or forest as well as associated map data such as political units and Federal land ownership. The fourth type, the Geographic Names Information System, provides primary information for all known places, features, and areas in the United States identified by a proper name.

U.S. Geological Survey

1993-01-01

53

The Lloyd L. Gaines Collection  

NSDL National Science Digital Library

Born in 1911, Lloyd Lionel Gaines was one of eleven children. Gaines excelled in his studies and applied to the University of Missouri School of Law in 1936. He was denied admission solely on the grounds that Missouri's state constitution called for "separate education of the races." Gaines did not back down from this injustice, and he sought legal assistance from the NAACP. In 1938, Gaines won his case before the United States Supreme Court, but tragically Gaines disappeared at age 28 in Chicago and was never seen or heard from again. This engaging collection from the University of Missouri Law Library brings together documents related to Gaines's life, including photographs, family correspondence, materials related to his Supreme Court case, and related secondary materials. Visitors to the site can perform a simple search across all the materials, or dig in deeper by perform a citation search. Legal scholars will find the Case Materials area particularly engaging, as it includes links to the trial briefs, respondents' statements, and so on.

54

Adaptive allocation of attentional gain  

PubMed Central

Humans are adept at distinguishing between stimuli that are very similar, an ability that is particularly crucial when the outcome is of serious consequence (e.g. for a surgeon or air traffic controller). Traditionally, selective attention was thought to facilitate perception by increasing the gain of sensory neurons tuned to the defining features of a behaviorally relevant object (e.g. color, orientation, etc.). In contrast, recent mathematical models counter-intuitively suggest that in many cases attentional gain should be applied to neurons that are tuned away from relevant features, especially when discriminating highly similar stimuli. Here we used psychophysical methods to critically evaluate these ‘ideal observer’ models. The data demonstrate that attention enhances the gain of the most informative sensory neurons, even when these neurons are tuned away from the behaviorally relevant target feature. Moreover, the degree to which an individual adopted optimal attentional gain settings by the end of testing predicted success rates on a difficult visual discrimination task, as well as the amount of task improvement that occurred across repeated testing sessions (learning). Contrary to most traditional accounts, these observations suggest that the primary function of attentional gain is not simply to enhance the representation of target features, but to optimize performance on the current perceptual task. Additionally, individual differences in gain suggest that the operating characteristics of low-level attentional phenomena are not stable trait-like attributes and that variability in how attention is deployed may play an important role in determining perceptual abilities. PMID:19776279

Scolari, Miranda; Serences, John T.

2009-01-01

55

Factors affecting feedlot gains of Hereford bulls  

E-print Network

correlation coefficients between 140-day gain, age, gain from weaning to start, initial condition and initial weight 19 5. General outline for nested analysis 21 6. Correlation coefficients between various periods of 140-day gain test... for initial condition groups 2S 30 Mean gain per period for gain from weaning to start groups . 32 INTRODUCTIOH Differences in the ability of individuals to gain weight have long bean recognised; however, gain records have not been recommended ss a...

Thomas, Richard Carroll

2012-06-07

56

Elevated temperature biaxial fatigue  

NASA Technical Reports Server (NTRS)

A three year experimental program for studying elevated temperature biaxial fatigue of a nickel based alloy Hastelloy-X has been completed. A new high temperature fatigue test facility with unique capabilities has been developed. Effort was directed toward understanding multiaxial fatigue and correlating the experimental data to the existing theories of fatigue failure. The difficult task of predicting fatigue lives for non-proportional loading was used as an ultimate test for various life prediction methods being considered. The primary means of reaching improved undertanding were through several critical non-proportional loading experiments. It was discovered that the cracking mode switched from primarily cracking on the maximum shear planes at room temperature to cracking on the maximum normal strain planes at 649 C.

Jordan, E. H.

1984-01-01

57

Flight performance and competitive displacement of hummingbirds across elevational gradients.  

PubMed

Hummingbirds, with their impressive flight ability and competitive aerial contests, make ideal candidates for applying a mechanistic approach to studying community structure. Because flight costs are influenced by abiotic factors that change systematically with altitude, elevational gradients provide natural experiments for hummingbird flight ecology. Prior attempts relied on wing disc loading (WDL) as a morphological surrogate for flight performance, but recent analyses indicate this variable does not influence either territorial behavior or competitive ability. Aerodynamic power, by contrast, can be derived from direct measurements of performance and, like WDL, declines across elevations. Here, I demonstrate for a diverse community of Andean hummingbirds that burst aerodynamic power is associated with territorial behavior. Along a second elevational gradient in Colorado, I tested for correlated changes in aerodynamic power and competitive ability in two territorial hummingbirds. This behavioral analysis revealed that short-winged Selasphorus rufus males are dominant over long-winged Selasphorus platycercus males at low elevations but that the roles are reversed at higher elevations. Several lines of evidence support the hypothesis that the burst rather than sustained aerodynamic performance mediates competitive ability at high elevation. A minimum value for burst power may be required for successful competition, but other maneuverability features gain importance when all competitors have sufficient muscle power, as occurs at low elevations. PMID:16670982

Altshuler, Douglas L

2006-02-01

58

Elevation leads to altruistic behavior.  

PubMed

Feelings of elevation, elicited by witnessing another person perform a good deed, have been hypothesized to motivate a desire to help others. However, despite growing interest in the determinants of prosocial behavior, there is only limited evidence that elevation leads to increases in altruistic behavior. In two experiments, we tested the relationship between elevation and helping behavior. Prior to measuring helping behavior, we measured elevation among participants in an elevation-inducing condition and control conditions in order to determine whether witnessing altruistic behavior elicited elevation. In Experiment 1, participants experiencing elevation were more likely to volunteer for a subsequent unpaid study than were participants in a neutral state. In Experiment 2, participants experiencing elevation spent approximately twice as long helping the experimenter with a tedious task as participants experiencing mirth or a neutral emotional state. Further, feelings of elevation, but not feelings of amusement or happiness, predicted the amount of helping. Together, these results provide evidence that witnessing another person's altruistic behavior elicits elevation, a discrete emotion that, in turn, leads to tangible increases in altruism. PMID:20424062

Schnall, Simone; Roper, Jean; Fessler, Daniel M T

2010-03-01

59

Welfare Gains from Financial Liberalization  

PubMed Central

Financial liberalization has been a controversial issue, as empirical evidence for growth enhancing effects is mixed. Here, we find sizable welfare gains from liberalization (cost to repression), though the gain in economic growth is ambiguous. We take the view that financial liberalization is a government policy that alters the path of financial deepening, while financial deepening is endogenously chosen by agents given a policy and occurs in transition towards a distant steady state. This history-dependent view necessitates the use of simulation analysis based on a growth model. Our application is a specific episode: Thailand from 1976 to 1996. PMID:20806055

Townsend, Robert M.; Ueda, Kenichi

2010-01-01

60

Low gain and steerable vehicle antennas for communications with land mobile satellite  

NASA Technical Reports Server (NTRS)

Current development activities at JPL for ground mobile vehicle antennas to be used with the Land Mobile Satellite Service (LMSS) system are described. Both low gain and electronically steerable high gain type antennas are discussed in terms of their design concept and RF performance. For the low gain type, three classes of antennas are under various stages of development. These are the crossed-drooping dipole, quadrifilar helix, and microstrip patch designs. The antennas are intended to provide circularly-polarized radiation with a minimum of 3-dB gain in the angular region from 19 degrees to 60 deg from the horizon in elevation plane and with an omnidirectional pattern in azimuthal plane. For the electronically steerable high gain type, circularly-polarized microstrip patch phased arrays formed on a planar surface and on the surface of a truncated cone are under study. The arrays are intended to provide a minimum of 12 dB gain in the same angular region in elevation plane at all azimuthal angles. This coverage is accomplished by scanning the high gain pencil beam in both elevation and azimuthal directions. Both types of antennas are to transmit at 821-831 MHz band and to receive at 866-876 MHz band. They must be of low cost design and reasonably conformal to the vehicle.

Woo, K.

1982-01-01

61

Elevated temperature biaxial fatigue  

NASA Technical Reports Server (NTRS)

A 3 year experimental program for studying elevated temperature biaxial fatigue of a nickel based alloy Hastelloy-X has been completed. A new high temperature fatigue test facility with unique capabilities has been developed. Effort was directed toward understanding multiaxial fatigue and correlating the experimental data to the existing theories of fatigue failure. The difficult task of predicting fatigue lives for nonproportional loading was used as an ultimate test for various life prediction methods being considered. The primary means of reaching improved understanding were through several critical nonproportional loading experiments. The direction of cracking observed on failed specimens was also recorded and used to guide the development of the theory. Cyclic deformation responses were permanently recorded digitally during each test. It was discovered that the cracking mode switched from primarily cracking on the maximum shear planes at room temperature to cracking on the maximum normal strain planes at 649 C. In contrast to some other metals, loading path in nonproportional loading had little effect on fatigue lives. Strain rate had a small effect on fatigue lives at 649 C. Of the various correlating parameters the modified plastic work and octahedral shear stress were the most successful.

Jordan, E. H.

1985-01-01

62

The Gains from Vertical Scaling  

ERIC Educational Resources Information Center

It is often assumed that a vertical scale is necessary when value-added models depend upon the gain scores of students across two or more points in time. This article examines the conditions under which the scale transformations associated with the vertical scaling process would be expected to have a significant impact on normative interpretations…

Briggs, Derek C.; Domingue, Ben

2013-01-01

63

PATTERNS FOR GAINING DIFFERENT PERSPECTIVES  

E-print Network

PATTERNS FOR GAINING DIFFERENT PERSPECTIVES A part of the Pedagogical Patterns Project pattern into play at just the right time to enhance student learning. The Pedagogical Patterns Project (www was written by Astrid Fricke and Markus Voelter [AF] and revised by Jutta Eckstein. Communication always takes

Wallingford, Eugene

64

CENTER: EAST ELEVATION OF BESSEMER BUILDING; LEFT: CHARGING HOUSE, ELEVATED ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

CENTER: EAST ELEVATION OF BESSEMER BUILDING; LEFT: CHARGING HOUSE, ELEVATED FROM HOT METAL BRIDGE, LOOKING SW. - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

65

35. Coal Fuel Elevator (diagonal in center), Fuel Elevator (left), ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. Coal Fuel Elevator (diagonal in center), Fuel Elevator (left), Fuel Storage Bins (center), and Power Plant (far center), and Retail Coal Storage Bins (right) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

66

34. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), Fuel Storage Bins (center), and Power Plant (far center), and Retail Coal Storage Bins (right) Photograph taken by George Harven - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

67

Clinical Gains from Including Both Dextroamphetamine and Methylphenidate in Stimulant Trials  

PubMed Central

Abstract Objective The purpose of this study was to investigate clinical gains from including both dextroamphetamine and methylphenidate in stimulant trials. Method Thirty-six medication-naïve children ages 9–14 years diagnosed with attention-deficit/hyperactivity disorder (ADHD) were enrolled for 6 weeks in a crossover trial, with 2 weeks of methylphenidate, dextroamphetamine, and placebo, in a randomly assigned, counterbalanced sequence. Outcome measures constituted a computer-based continuous performance test combined with a motion tracking system (Qb Test) and an ADHD questionnaire rated by parents and teachers. Results Group analyses found significant treatment effects of similar size for the two stimulants on both outcome measures. Single-subject analyses revealed that each stimulant produced a favourable response in 26 children; however, an individual child frequently responded qualitatively or quantitatively differently to the two stimulants. By including both stimulants in the trial, the number of favorable responders increased from 26 (72%) to 33 (92%). In children with favorable responses of unequal strength to the two stimulants, a shift from inferior drug to best drug was associated with a 64% mean increase in the overall response strength score, as measured by the ADHD questionnaire. Conclusions The likelihood of a favorable response and optimal response strength is increased by including both stimulants in the stimulant trial. The study was first registered in clinical trials 28 September 2010. Clinical Trials.gov Identifier: NCT01220440. PMID:23659360

Røinås, Elisabeth; Aabech, Henning S.; Sundet, Kjetil S.

2013-01-01

68

Space Station tethered elevator system  

NASA Technical Reports Server (NTRS)

The optimized conceptual engineering design of a space station tethered elevator is presented. The tethered elevator is an unmanned, mobile structure which operates on a ten-kilometer tether spanning the distance between Space Station Freedom and a platform. Its capabilities include providing access to residual gravity levels, remote servicing, and transportation to any point along a tether. The report discusses the potential uses, parameters, and evolution of the spacecraft design. Emphasis is placed on the elevator's structural configuration and three major subsystem designs. First, the design of elevator robotics used to aid in elevator operations and tethered experimentation is presented. Second, the design of drive mechanisms used to propel the vehicle is discussed. Third, the design of an onboard self-sufficient power generation and transmission system is addressed.

Haddock, Michael H.; Anderson, Loren A.; Hosterman, K.; Decresie, E.; Miranda, P.; Hamilton, R.

1989-01-01

69

Lifestyle intervention can prevent weight gain during menopause: Results from a 5-year randomized clinical trial  

Microsoft Academic Search

Context: Menopausal-related weight gain and increased waist circumference have major cardiovascular health implications for older\\u000a women. The efficacy of a dietary and physical activity lifestyle intervention to prevent weight gain and elevations in cardiovascular\\u000a disease (CVD) risk factors from the peri- to postmenopause is unknown.Objective: To report the 54-month results of a lifestyle dietary and physical activity program on weight,

Laurey R. Simkin-Silverman; Rena R. Wing; Miriam A. Boraz; Lewis H. Kuller

2003-01-01

70

Randoms and TOF gain revisited.  

PubMed

Time-of-flight (TOF) positron emission tomography (PET) typically reduces the variance in the images by a factor that is proportional to the size of the object to be scanned, and inversely proportional to the time resolution of the PET scanner. Attempts to better characterize this relationship and understand its limits have been published, showing that such gain also increases with random fraction. In this paper, new experimental and simulated data are analyzed and old results are incorporated in the study. The proportionality of TOF gain with time resolution is confirmed, the proportionality constant is measured, the effect of the randoms is validated, and the limit of the model for small objects is investigated. PMID:25615713

Eriksson, Lars; Conti, Maurizio

2015-02-21

71

Randoms and TOF gain revisited  

NASA Astrophysics Data System (ADS)

Time-of-flight (TOF) positron emission tomography (PET) typically reduces the variance in the images by a factor that is proportional to the size of the object to be scanned, and inversely proportional to the time resolution of the PET scanner. Attempts to better characterize this relationship and understand its limits have been published, showing that such gain also increases with random fraction. In this paper, new experimental and simulated data are analyzed and old results are incorporated in the study. The proportionality of TOF gain with time resolution is confirmed, the proportionality constant is measured, the effect of the randoms is validated, and the limit of the model for small objects is investigated.

Eriksson, Lars; Conti, Maurizio

2015-02-01

72

Scalar gain interpretation of large order filters  

NASA Technical Reports Server (NTRS)

A technique is developed which demonstrates how to interpret a large fully-populated filter gain matrix as a set of scalar gains. The inverse problem is also solved, namely, how to develop a large-order filter gain matrix from a specified set of scalar gains. Examples are given to illustrate the method.

Mason, Paul A. C.; Mook, D. Joseph

1993-01-01

73

1. 'Front Elevation, End Elevation of Parapet, Section on Centerline ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. 'Front Elevation, End Elevation of Parapet, Section on Centerline of Portal,' Southern Pacific Standard Single-Track Tunnel, 1909. Compare to photos in documentation sets for Tunnel 23 (HAER No. CA-198), Tunnel 24 (HAER No. CA-200), Tunnel 25 (HAER No. CA-201), Tunnel 27 (HAER No. CA-203), Tunnel 28 (HAER No. CA-204), and Tunnel 29 (HAER No. CA-205). - Central Pacific Transcontinental Railroad, Sacramento to Nevada state line, Sacramento, Sacramento County, CA

74

Actinide Thermodynamics at Elevated Temperatures  

SciTech Connect

The postclosure chemical environment in the proposed Yucca Mountain repository is expected to experience elevated temperatures. Predicting migration of actinides is possible if sufficient, reliable thermodynamic data on hydrolysis and complexation are available for these temperatures. Data are scarce and scattered for 25 degrees C, and nonexistent for elevated temperatures. This collaborative project between LBNL and PNNL collects thermodynamic data at elevated temperatures on actinide complexes with inorganic ligands that may be present in Yucca Mountain. The ligands include hydroxide, fluoride, sulfate, phosphate and carbonate. Thermodynamic parameters of complexation, including stability constants, enthalpy, entropy and heat capacity of complexation, are measured with a variety of techniques including solvent extraction, potentiometry, spectrophotometry and calorimetry

Friese, Judah I.; Rao, Linfeng; Xia, Yuanxian; Bachelor, Paula P.; Tian, Guoxin

2007-11-16

75

Elevation Derivatives for National Applications  

USGS Publications Warehouse

The Elevation Derivatives for National Applications (EDNA) project is a multi-agency effort to develop standard topographically derived layers for use in hydrologic and environmental modeling. The EDNA takes advantage of the seamless and filtered characteristics for the National Elevation Dataset (NED) to create a hydrologically conditioned Digital Elevation Model (DEM) useful for modeling applications. The goals of the project are to create a hydrologically conditioned DEM and systematically extract a set of standard derivatives that can be used to facilitate data integration with other U.S. Geological Survey (USGS) framework data sets such as the National Hydrography Dataset (NHD) and the Watershed Boundaries Dataset (WBD).

U.S. Geological Survey

2005-01-01

76

[Fast food promotes weight gain].  

PubMed

The total amounts of fat in a fast food menu consisting of French fries and fried Chicken Nuggets from McDonald's and KFC, respectively, bought in 35 different countries vary from 41 to 71 gram. In most countries the menu contained unacceptably high amounts of industrially-produced trans fat which contributes to an increased risk of ischaemic heart disease, weight gain, abdominal fat accumulation and type 2 diabetes. The quality of the ingredients in fast food ought to be better and the size of the portions smaller and less energy-dense so that frequent fast food meals do not increase the risk of obesity and diseases among customers. PMID:17537359

Stender, Steen; Dyerberg, Jørn; Astrup, Arne V

2007-05-01

77

Commutated automatic gain control system  

NASA Technical Reports Server (NTRS)

The commutated automatic gain control (AGC) system was designed and built for the prototype Loran-C receiver is discussed. The current version of the prototype receiver, the Mini L-80, was tested initially in 1980. The receiver uses a super jolt microcomputer to control a memory aided phase loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The AGC control adjusts the level of each station signal, such that the early portion of each envelope rise is about at the same amplitude in the receiver envelope detector.

Yost, S. R.

1982-01-01

78

ConcepTest: Elevated Terraces  

NSDL National Science Digital Library

A series of elevated terraces (former wave-cut platforms) along an active plate boundary coast is evidence for ______________. a. Sea level rise b. Uplift of continental crust c. Subsidence (sinking) of crust

79

Advanced energy saving hydraulic elevator  

SciTech Connect

An hydraulic elevator is described comprising: a counterweighted elevator comprising a car, a counterweight, and a rope connecting the car and the counterweight; a ram having a first reaction surface for driving one of the car or the counterweight upwardly and a second reaction surface for driving one of the car or the counterweight downwardly; multiplier means for moving the car a distance greater than a stroke of the ram, the multiplier means connecting the ram to the counterweighted elevator, the multiplier means comprising: a first pulley; a second pulley; means for rigidly connecting the first and second pulley, the means having a length corresponding to a rise of the hydraulic elevator, the means attaching to the ram; and a pulley rope which: has a first end attaching to a first fixed point, extends about the first pulley, extends about the second pulley, and has a second end attaching to a second fixed point.

Garrido, A.; Sevilleja, J.; Servia, A.

1993-08-24

80

Elevated CO2 enhances biological contributions to elevation change in coastal wetlands by offsetting stressors associated with sea-level rise  

USGS Publications Warehouse

1. Sea-level rise, one indirect consequence of increasing atmospheric CO2, poses a major challenge to long-term stability of coastal wetlands. An important question is whether direct effects of elevated CO 2 on the capacity of marsh plants to accrete organic material and to maintain surface elevations outweigh indirect negative effects of stressors associated with sea-level rise (salinity and flooding). 2. In this study, we used a mesocosm approach to examine potential direct and indirect effects of atmospheric CO2 concentration, salinity and flooding on elevation change in a brackish marsh community dominated by a C3 species, Schoenoplectus americanus, and a C4 grass, Spartina patens. This experimental design permitted identification of mechanisms and their role in controlling elevation change, and the development of models that can be tested in the field. 3. To test hypotheses related to CO2 and sea-level rise, we used conventional anova procedures in conjunction with structural equation modelling (SEM). SEM explained 78% of the variability in elevation change and showed the direct, positive effect of S. americanus production on elevation. The SEM indicated that C3 plant response was influenced by interactive effects between CO2 and salinity on plant growth, not a direct CO2 fertilization effect. Elevated CO2 ameliorated negative effects of salinity on S. americanus and enhanced biomass contribution to elevation. 4. The positive relationship between S. americanus production and elevation change can be explained by shoot-base expansion under elevated CO 2 conditions, which led to vertical soil displacement. While the response of this species may differ under other environmental conditions, shoot-base expansion and the general contribution of C3 plant production to elevation change may be an important mechanism contributing to soil expansion and elevation gain in other coastal wetlands. 5. Synthesis. Our results revealed previously unrecognized interactions and mechanisms contributing to marsh elevation change, including amelioration of salt stress by elevated CO2 and the importance of plant production and shoot-base expansion for elevation gain. Identification of biological processes contributing to elevation change is an important first step in developing comprehensive models that permit more accurate predictions of whether coastal marshes will persist with continued sea-level rise or become submerged. ?? 2008 The Authors.

Cherry, J.A.; McKee, K.L.; Grace, J.B.

2009-01-01

81

An improved empirical model for diversity gain on Earth-space propagation paths  

NASA Technical Reports Server (NTRS)

An empirical model was generated to estimate diversity gain on Earth-space propagation paths as a function of Earth terminal separation distance, link frequency, elevation angle, and angle between the baseline and the path azimuth. The resulting model reproduces the entire experimental data set with an RMS error of 0.73 dB.

Hodge, D. B.

1981-01-01

82

2. 'Tunnel No 6 West End, Front Elevation, Sectional Elevation ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. 'Tunnel No 6 West End, Front Elevation, Sectional Elevation on Centerline of Portal,' Southern Pacific Standard Single-Track Tunnel, 1910. Tunnel 6, which today would be Tunnel 20, was daylighted and no longer exists. Compare to photos in documentation sets for Tunnel 23 (HAER No. CA-198), Tunnel 24 (HAER No. CA-200), Tunnel 25 (HAER No. CA-201), Tunnel 27 (HAER No. CA-203), Tunnel 28 (HAER No. CA-204), and Tunnel 29 (HAER No. CA-205). - Central Pacific Transcontinental Railroad, Sacramento to Nevada state line, Sacramento, Sacramento County, CA

83

CCPPolicyBriefing Gain or Pain  

E-print Network

CCPPolicyBriefing July 2008 Gain or Pain: Does Consumer Activity Reflect Utility Maximisation? W: www.ccp.uea.ac.uk T: +44 (0)1603 593715 A: UEA, Norwich, NR4 7TJ Gain or Pain: Does Consumer Activity. #12;CCPPolicyBriefing July 2008 Gain or Pain: Does Consumer Activity Reflect Utility Maximisation? W

Feigon, Brooke

84

Gain scheduled control of perturbed standing balance  

Microsoft Academic Search

This paper develops full-state parametric controllers for standing balance of humanoid robots in response to impulsive and constant pushes. We also explore a hypothesis that postural feedback gains in standing balance should change with perturbation size. From an engineering point of view this is known as gain scheduling. We use an optimization approach to see if feedback gains should scale

Dengpeng Xing; Christopher G. Atkeson; Jianbo Su; Benjamin J. Stephens

2010-01-01

85

VECSEL gain characterization Mario Mangold,1,*  

E-print Network

VECSEL gain characterization Mario Mangold,1,* Valentin J. Wittwer,1 Oliver D. Sieber,1 Martin (VECSEL) gain chips with similar designs operating in the 960-nm wavelength regime. We optically pump. With this technique we are able to measure the saturation behavior for VECSEL gain chips for the first time

Keller, Ursula

86

Effective Gain Measurement in Quantum Cascade Lasers  

E-print Network

Effective Gain Measurement in Quantum Cascade Lasers A new method to measure gain in Quantum, PRISM, *BYU Supported by NSF, PRISM #12;Outline Lasers ­ The Basics Quantum Cascade Lasers Gain and Loss unchanged http://www.ux1.eiu.edu/~cfadd/1160/Ch29Atm/Laser.html #12;Quantum Cascade Laser Laser Bar Sample

Petta, Jason

87

Modeling gain saturation in neodymium laser glasses  

Microsoft Academic Search

Gain saturation in neodymium laser glasses was modeled using a simplified treatment of the spectroscopic inhomogeneities and experimental parameters obtained from broadband- and laser-excited fluorescence spectroscopy. The predicted large-signal gain behavior for two silicate and two phosphate glasses agrees with measured gain saturation within the experimental uncertainties. The results are extended to treat saturation of other Nd-doped glasses.

D. W. Hall; M. J. Weber

1984-01-01

88

Gestational weight gain among Hispanic women.  

PubMed

To describe gestational weight gain among Hispanic women and to examine psychological, social, and cultural contexts affecting weight gain. A total of 282 Hispanic women were surveyed post-partum before leaving the hospital. Women were queried about their prepregnancy weight and weight gained during pregnancy. Adequacy of gestational weight gain was based on guidelines set by the Institute of Medicine in 2009. Independent risk factors for excessive or insufficient weight gain were examined by logistic regression. Most women were unmarried (59 %), with a mean age of 28.4 ± 6.6 years and an average weight gain of 27.9 ± 13.3 lbs. Approximately 45 % of women had gained too much, 32 % too little, and only 24 % had an adequate amount of weight gain. The mean birth weight was 7.3, 7.9, and 6.8 lbs among the adequate, excessive, and insufficient weight gain groups. Among women who exercised before pregnancy, two-thirds continued to do so during pregnancy; the mean gestational weight gain of those who continued was lower than those who stopped (26.8 vs. 31.4 lbs, p = 0.04). Independent risk factors for excessive weight gain were being unmarried, U.S. born, higher prepregnancy body mass index, and having indifferent or negative views about weight gain. Independent risk factors for insufficient weight gain were low levels of support and late initiation of prenatal care. Depression, stress, and a woman's or her partner's happiness regarding pregnancy were unrelated to weight gain. The results of this study can be used by prenatal programs to identify Hispanic women at risk for excessive or insufficient gestational weight gain. PMID:23456347

Sangi-Haghpeykar, Haleh; Lam, Kim; Raine, Susan P

2014-01-01

89

Elevation leads to altruistic behavior  

E-print Network

-management considerations. Using a clip from an episode of “The Oprah Winfrey Show” in which musicians thanked the teachers who had mentored them, Silvers and Haidt (2008) elicited elevation in nursing U.S. mothers; during the 5 min that followed viewing the video clip... the experiment, and one guessed the hypothesis. Materials. The stimulus for the elevation condition was the 7-min clip from “The Oprah Winfrey Show” used by Silvers and Haidt (2008). The stimulus for the control condition was the first 7 min of “The Open Ocean...

Schnall, Simone; Roper, Jean; Fessler, Daniel M. T.

2010-01-01

90

Power gain of a SQUID amplifier  

NASA Astrophysics Data System (ADS)

The power gain of a dc superconducting quantum interference device (SQUID) amplifier, with tuned input and output circuits, is computed as a function of the current and magnetic biases. A gain of 20300 is found at 1.5 GHz and 3470 at 3.0 GHz, implying a frequency dependence to the gain of approximately 1/omega-squared. The gain, as derived from the resistively shunted junction model, is compared with the gain of a simplified model based on the dc magnetic response V(phi). This comparison shows that the V(phi) description of the SQUID can lead to large errors.

McDonald, D. G.

1984-03-01

91

Weight Gain, Obesity, and Psychotropic Prescribing  

PubMed Central

A majority of psychiatric medications are known to generate weight gain and ultimately obesity in some patients. There is much speculation about the prevalence of weight gain and the degree of weight gain during acute and longitudinal treatment with these agents. There is newer literature looking at the etiology of this weight gain and the potential treatments being used to alleviate this side effect. The authors undertook a comprehensive literature review in order to present epidemiology, etiology, and treatment options of weight gain associated with antipsychotics, mood stabilizers, and antidepressants. PMID:21318056

Nihalani, Nikhil; Schwartz, Thomas L.; Siddiqui, Umar A.; Megna, James L.

2011-01-01

92

ST-segment elevation: Distinguishing ST elevation myocardial infarction from ST elevation secondary to nonischemic etiologies  

PubMed Central

The benefits of early perfusion in ST elevation myocardial infarctions (STEMI) are established; however, early perfusion of non-ST elevation myocardial infarctions has not been shown to be beneficial. In addition, ST elevation (STE) caused by conditions other than acute ischemia is common. Non-ischemic STE may be confused as STEMI, but can also mask STEMI on electrocardiogram (ECG). As a result, activating the primary percutaneous coronary intervention (pPCI) protocol often depends on determining which ST elevation patterns reflect transmural infarction due to acute coronary artery thrombosis. Coordination of interpreting the ECG in its clinical context and appropriately activating the pPCI protocol has proved a difficult task in borderline cases. But its importance cannot be ignored, as reflected in the 2013 American College of Cardiology Foundation/American Heart Association guidelines concerning the treatment of ST elevation myocardial infarction. Multiples strategies have been tested and studied, and are currently being further perfected. No matter the strategy, at the heart of delivering the best care lies rapid and accurate interpretation of the ECG. Here, we present the different patterns of non-ischemic STE and methods of distinguishing between them. In writing this paper, we hope for quicker and better stratification of patients with STE on ECG, which will lead to be better outcomes. PMID:25349651

Deshpande, Alok; Birnbaum, Yochai

2014-01-01

93

ST-segment elevation: Distinguishing ST elevation myocardial infarction from ST elevation secondary to nonischemic etiologies.  

PubMed

The benefits of early perfusion in ST elevation myocardial infarctions (STEMI) are established; however, early perfusion of non-ST elevation myocardial infarctions has not been shown to be beneficial. In addition, ST elevation (STE) caused by conditions other than acute ischemia is common. Non-ischemic STE may be confused as STEMI, but can also mask STEMI on electrocardiogram (ECG). As a result, activating the primary percutaneous coronary intervention (pPCI) protocol often depends on determining which ST elevation patterns reflect transmural infarction due to acute coronary artery thrombosis. Coordination of interpreting the ECG in its clinical context and appropriately activating the pPCI protocol has proved a difficult task in borderline cases. But its importance cannot be ignored, as reflected in the 2013 American College of Cardiology Foundation/American Heart Association guidelines concerning the treatment of ST elevation myocardial infarction. Multiples strategies have been tested and studied, and are currently being further perfected. No matter the strategy, at the heart of delivering the best care lies rapid and accurate interpretation of the ECG. Here, we present the different patterns of non-ischemic STE and methods of distinguishing between them. In writing this paper, we hope for quicker and better stratification of patients with STE on ECG, which will lead to be better outcomes. PMID:25349651

Deshpande, Alok; Birnbaum, Yochai

2014-10-26

94

Achieving yield gains in wheat.  

PubMed

Wheat provides 20% of calories and protein consumed by humans. Recent genetic gains are <1% per annum (p.a.), insufficient to meet future demand. The Wheat Yield Consortium brings expertise in photosynthesis, crop adaptation and genetics to a common breeding platform. Theory suggest radiation use efficiency (RUE) of wheat could be increased ~50%; strategies include modifying specificity, catalytic rate and regulation of Rubisco, up-regulating Calvin cycle enzymes, introducing chloroplast CO(2) concentrating mechanisms, optimizing light and N distribution of canopies while minimizing photoinhibition, and increasing spike photosynthesis. Maximum yield expression will also require dynamic optimization of source: sink so that dry matter partitioning to reproductive structures is not at the cost of the roots, stems and leaves needed to maintain physiological and structural integrity. Crop development should favour spike fertility to maximize harvest index so phenology must be tailored to different photoperiods, and sensitivity to unpredictable weather must be modulated to reduce conservative responses that reduce harvest index. Strategic crossing of complementary physiological traits will be augmented with wide crossing, while genome-wide selection and high throughput phenotyping and genotyping will increase efficiency of progeny screening. To ensure investment in breeding achieves agronomic impact, sustainable crop management must also be promoted through crop improvement networks. PMID:22860982

Reynolds, Matthew; Foulkes, John; Furbank, Robert; Griffiths, Simon; King, Julie; Murchie, Erik; Parry, Martin; Slafer, Gustavo

2012-10-01

95

Special Issue: High Elevation Forests  

E-print Network

Vegetation Most of us know them as destinations for skiing, hiking, camping, aspen viewing, firewood of these ecosystems are approximate, as ranges vary from location to location.) Elevation(feet) Alpine Tundra Forest-Alpine Ecotone Sub-Alpine Forest Upper Montane Lower Montane Lower Ecotone Shrubland Shortgrass Steppe Bill

96

DIVISION 14 -CONVEYING SYSTEMS 14200 ELEVATORS  

E-print Network

on reproducible mylar drawings indicating the control wiring, motor data, and all pertinent elevator PART III DESIGN STANDARDS MANUAL AUGUST 2000 #12;The elevator manufacturer / vendor shall provide a new control ELEVATORS 1. As a minimum, comply with applicable requirements of the "Safety Code for Elevators

97

Elevator deflections on the icing process  

NASA Technical Reports Server (NTRS)

The effect of elevator deflection of the horizontal stabilizer for certain icing parameters is investigated. Elevator deflection can severely change the lower and upper leading-edge impingement limits, and ice can accrete on the elevator itself. Also, elevator deflection had practically no effect on the maximum local collection efficiency. It is shown that for severe icing conditions (large water droplets), elevator deflections that increase the projected height of the airfoil can significantly increase the total collection efficiency of the airfoil.

Britton, Randall K.

1990-01-01

98

Gain and loss mechanisms in fluorocarbon plasmas  

NASA Astrophysics Data System (ADS)

Understanding dominant reaction channels for important gas-phase species in fluorocarbon plasmas is crucial to the ability to control surface evolution and morphology. In order to accomplish this goal a modified GEC reference ICP reactor is used in tandem with Fourier transform infrared spectroscopy (FTIR) to measure the densities of stable species. Integrated absorption cross-sections are presented for all fundamental bands in the 650 cm-1 to 2000 cm-1 region for C3F6, C4F 8, C3F8, C2F6, C2F 4, and CF4. The results show that although the absorption profile changes significantly, the integrated absorption cross-sections, with the exception of CF4, do not change significantly as gas temperature increases from 25°C to 200°C. However, the internal temperature of the absorbing species can be estimated from the rotational band maximum in most cases. Species densities obtained with the aforementioned cross-sections are used with a novel analysis technique to quantify gain and loss rates as functions of residence time, pressure, and deposited power. CF4, C2F6, C3F8, and C4F 10, share related production channels, which increase in magnitude as the plasma pressure, deposited power, or surface temperature are raised. CF 2 is primarily produced through a combination of surface production (the magnitude also increases with temperature) and electron impact dissociation of C2F4, while it is predominantly lost in the large reactor to gas-phase addition to form C2F4. Time-resolved FTIR results are used to measure a cross-section of 1.8x10-14 cm3/s for the reaction between CF2 radicals creating C2F4. Finally, C2F4 originates through the electron impact dissociation of c- C4F8. The loss process for C2F4 is undetermined, but the results indicate that it could occur on reactor surfaces. Neither the density of fluorine nor the ion flux to the chuck surface changes substantially with wall temperature. We show that increases in the deposition rate in a heated chamber are due to an increase in the fluxes of depositing neutral species. Furthermore, the sticking coefficient for these species does not change significantly as a function of surface temperature. Instead, surface temperature elevates the yield of etchant species, which terminate broken bonds to increase the desorption rates of stable species.

Nelson, Caleb Timothy

99

Microchannel plate modal gain variations with temperature  

NASA Technical Reports Server (NTRS)

Measurements of the modal gain of two high-gain curved-channel microchannel plates (MCPs) at various operating temperatures are presented. Both MCPs were fabricated from the Long Life glass with 12-micron diam channels on 15-micron centers. The modal gain was found to decrease with increasing temperature at a rate of -0.1 percent C. This reduction of gain with temperature is attributed primarily to an axial temperature gradient along each MCP channel creating a nonuniform electric field within the channel that lowers the effective output gain. A lowering of the secondary electron yield resulting from increased phonon scattering of secondary electrons released within the walls of the MCP channels was assessed, but was found to have a negligible contribution to the drop in gain with temperature.

Slater, David C.; Timothy, J. G.

1993-01-01

100

Planar High-Gain WLAN PCB Antenna  

Microsoft Academic Search

A simple design for a low-profile high-gain planar antenna has been presented in the letter. The antenna has the realized gain between 9 and 11 dBi and the return loss better than 10 dB over the 5.6-6.3-GHz frequency band, i.e. 11% bandwidth. A numerical study highlighting effects of key geometrical parameters on the gain and return loss of the antenna

Dmitry E. Zelenchuk; Vincent F. Fusco

2009-01-01

101

WFC3 SMOV Proposal 11419: UVIS Gain  

NASA Astrophysics Data System (ADS)

This report summarizes the gain results obtained from the SMOV UVIS Detector Functional program, proposal #11419. Based on internal calibration flatfields, the gain at the nominal 1.5 setting was measured at 1.61, 1.61, 1.63, and 1.62 e-/DN, with errors <0.01 e- /DN, for quadrants A, B, C, and D, respectively. These values are ~3% higher than those measured in ground test images and to date have been stable on-orbit: a preliminary mea- surement of the recent Cycle 17 gain data (proposal 11906, PI Pavlovsky) yielded gains within 1% or better of the SMOV values. The off-nominal gain settings are restricted parameters and unavailable for general use, however, the SMOV proposal obtained data to check these settings on-orbit relative to the nominal 1.5 setting. The values for the off-nominal gains were measured at 1.04, 1.02, 1.04, 1.04 e-/DN and at 2.17, 2.12, 2.17, 2.16 e-/DN for the gain 1.0 and gain 2.0 settings. The exposure times for the gain 4.0 images were erroneously set too low to allow a determination of that setting; the observations were not repeated.

Baggett, S.; Borders, T.

2009-11-01

102

Elevated plasma lipid peroxide levels in angina pectoris and myocardial infarction  

Microsoft Academic Search

Background: The concept that oxidised low-density lipoprotein (LDL), not native LDL, plays a major role in atherogenesis is gaining support. Lipid hydroperoxides in plasma are carried almost exclusively in LDL and reflect oxidised LDL. Previously, elevated plasma lipid hydroperoxides were reported in coronary artery disease (CAD) patients following bypass surgery. To determine whether the increased lipid hydroperoxide was related to

Diana A. Gorog; Nabeel Ahmed; Graham J. Davies

2002-01-01

103

ST elevation without myocardial infarction.  

PubMed

Acute myocarditis may mimic myocardial infarction because the affected patients report 'classical' chest pain; the ECG changes and echocardiography are identical to those observed in acute coronary syndromes, and serum markers are increased. We describe a case with ST segment elevation on admission ECG, and coronary angiography was normal. Cardiac magnetic resonance with myocardial delayed enhancement sequences is a non-invasive alternative for diagnosing myocarditis. PMID:24711464

Bitar, Zouheir Ibrahim; Swede, Mohammad; Almerri, Khaled

2014-01-01

104

Multivariate temporal pattern analysis applied to the study of rat behavior in the elevated plus maze: methodological and conceptual highlights.  

PubMed

Aim of this article is to illustrate the application of a multivariate approach known as t-pattern analysis in the study of rat behavior in elevated plus maze. By means of this multivariate approach, significant relationships among behavioral events in the course of time can be described. Both quantitative and t-pattern analyses were utilized to analyze data obtained from fifteen male Wistar rats following a trial 1-trial 2 protocol. In trial 2, in comparison with the initial exposure, mean occurrences of behavioral elements performed in protected zones of the maze showed a significant increase counterbalanced by a significant decrease of mean occurrences of behavioral elements in unprotected zones. Multivariate t-pattern analysis, in trial 1, revealed the presence of 134 t-patterns of different composition. In trial 2, the temporal structure of behavior become more simple, being present only 32 different t-patterns. Behavioral strings and stripes (i.e. graphical representation of each t-pattern onset) of all t-patterns were presented both for trial 1 and trial 2 as well. Finally, percent distributions in the three zones of the maze show a clear-cut increase of t-patterns in closed arm and a significant reduction in the remaining zones. Results show that previous experience deeply modifies the temporal structure of rat behavior in the elevated plus maze. In addition, this article, by highlighting several conceptual, methodological and illustrative aspects on the utilization of t-pattern analysis, could represent a useful background to employ such a refined approach in the study of rat behavior in elevated plus maze. PMID:24932963

Casarrubea, M; Magnusson, M S; Roy, V; Arabo, A; Sorbera, F; Santangelo, A; Faulisi, F; Crescimanno, G

2014-08-30

105

Teacher predictions versus actual student gains  

NSDL National Science Digital Library

Presents a study where astronomy teachers (n=66) try to predict student (n=330) outcomes on astronomy and related topics pre- and posttest. Suggested findings include a course in astronomy did not result in an overall knowledge gain, teachers fared well at predicting prior student knowledge, and teachers vastly overestimated student gain in knowledge during the course.

Sadler, Philip M.; Lightman, Alan

2005-10-27

106

Gain scheduling using the Youla parameterization  

Microsoft Academic Search

Gain scheduling controllers are considered in this paper. The gain scheduling problem where the scheduling parameter vector ? cannot be measured directly, but needs to be estimated, is considered. An estimation of ? has been derived by using the Youla parametrization. The use of the Youla parameterization in connection with the estimation of ? gives a direct validation method for

Henrik Niemann; J. Stroustrup

1999-01-01

107

Fuzzy gain scheduling for flight control  

Microsoft Academic Search

This paper presents a method for design of fuzzy gain scheduled output feedback H? controllers for affine Takagi-Sugeno (TS) systems. The method relies on recent developments in design for classical gain scheduling, based on linear matrix inequalities. It is shown how the previous results can be extended to general nonlinear systems that admits a TS fuzzy system approximation. The design

P. Bergsten; M. Persson; B. Iliev

2000-01-01

108

Meaningful Reading Gains by Adult Literacy Learners  

ERIC Educational Resources Information Center

To obtain a fuller picture of the efficacy of reading instruction programs for adult literacy learners, gains by individual students were examined in a sample (n = 148) in which weak to moderate gains at the group level had been obtained in response to tutoring interventions that focused on strengthening basic decoding and fluency skills of low…

Scarborough, Hollis S.; Sabatini, John P.; Shore, Jane; Cutting, Laurie E.; Pugh, Kenneth; Katz, Leonard

2013-01-01

109

Importance of preventing weight gain in adulthood  

Microsoft Academic Search

In the last 20 years, there has been a dramatic upsurge in the average weight of Australian adults. In this period, on average, Australian women have gained 4.8 kg, whilst Australian men have gained 3.6 kg. Consequently, the prevalence of obesity in men has increased from 8% to 19% and in women from 7% to 21%. This threatens to wipe

Tim Gill

2002-01-01

110

Gain calibration methods for radio telescope arrays  

Microsoft Academic Search

In radio telescope arrays, the complex receiver gains and sensor noise powers are initially unknown and have to be calibrated. Gain calibration can enhance the quality of astronomical sky images and, moreover, improve the effectiveness of array signal processing techniques for interference mitigation and spatial filtering. A challenging aspect is that the signal-to-noise ratio (SNR) is usually well below 0

Albert-Jan Boonstra; Alle-Jan van der Veen

2003-01-01

111

Gain control mechanisms in spinal motoneurons.  

PubMed

Motoneurons provide the only conduit for motor commands to reach muscles. For many years, motoneurons were in fact considered to be little more than passive "wires". Systematic studies in the past 25 years however have clearly demonstrated that the intrinsic electrical properties of motoneurons are under strong neuromodulatory control via multiple sources. The discovery of potent neuromodulation from the brainstem and its ability to change the gain of motoneurons shows that the "passive" view of the motor output stage is no longer tenable. A mechanism for gain control at the motor output stage makes good functional sense considering our capability of generating an enormous range of forces, from very delicate (e.g., putting in a contact lens) to highly forceful (emergency reactions). Just as sensory systems need gain control to deal with a wide dynamic range of inputs, so to might motor output need gain control to deal with the wide dynamic range of the normal movement repertoire. Two problems emerge from the potential use of the brainstem monoaminergic projection to motoneurons for gain control. First, the projection is highly diffuse anatomically, so that independent control of the gains of different motor pools is not feasible. In fact, the system is so diffuse that gain for all the motor pools in a limb likely increases in concert. Second, if there is a system that increases gain, probably a system to reduce gain is also needed. In this review, we summarize recent studies that show local inhibitory circuits within the spinal cord, especially reciprocal and recurrent inhibition, have the potential to solve both of these problems as well as constitute another source of gain modulation. PMID:25120435

Johnson, Michael D; Heckman, Charles J

2014-01-01

112

Hurricane Katrina sediment slowed elevation loss in subsiding brackish marshes of the Mississippi River delta  

USGS Publications Warehouse

Although hurricanes can damage or destroy coastal wetlands, they may play a beneficial role in reinvigorating marshes by delivering sediments that raise soil elevations and stimulate organic matter production. Hurricane Katrina altered elevation dynamics of two subsiding brackish marshes in the Mississippi River deltaic plain by adding 3 to 8 cm of sediment to the soil surface in August 2005. Soil elevations at both sites subsequently declined due to continued subsidence, but net elevation gain was still positive at both Pearl River (+1.7 cm) and Big Branch (+0.7 cm) marshes two years after the hurricane. At Big Branch where storm sediments had higher organic matter and water contents, post-storm elevation loss was more rapid due to initial compaction of the storm layer in combination with root-zone collapse. In contrast, elevation loss was slower at Pearl River where the storm deposit (high sand content) did not compact and the root zone did not collapse. Vegetation at both sites fully recovered within one year, and accumulation of root matter at Big Branch increased 10-fold from 2005 to 2006, suggesting that the hurricane stimulated belowground productivity. Results of this study imply that hurricane sediment may benefit subsiding marshes by slowing elevation loss. However, long-term effects of hurricane sediment on elevation dynamics will depend not only on the amount of sediment deposited, but on sediment texture and resistance to compaction as well as on changes in organic matter accumulation in the years following the hurricane.

McKee, K.L.; Cherry, J.A.

2009-01-01

113

The oscillating wing with aerodynamically balanced elevator  

NASA Technical Reports Server (NTRS)

The two-dimensional problem of the oscillating wing with aerodynamically balanced elevator is treated in the manner that the wing is replaced by a plate with bends and stages and the airfoil section by a mean line consisting of one or more straights. The computed formulas and tables permit, on these premises, the prediction of the pressure distribution and of the aerodynamic reactions of oscillating elevators and tabs with any position of elevator hinge in respect to elevator leading edge.

Kussner, H G; Schwartz, I

1941-01-01

114

Active Gain Scheduling: A Collaborative Control Strategy between LPV Plants and Gain Scheduling Controllers  

Microsoft Academic Search

We propose a new collaborative control strategy between time varying design parameters of the plant and the feedback controller. As the feedback control law we adopt the LMI based gain scheduling control scheme to guarantee the closed-loop L2 gain performance against the variation of the time varying parameter of the control object. Under the gain scheduling control we propose a

Kazuhiko Hiramoto

2007-01-01

115

UC SAN DIEGO ELEVATOR LOCATIONS MAIN CAMPUS  

E-print Network

UC SAN DIEGO ELEVATOR LOCATIONS MAIN CAMPUS BUILDING # OF ELEVATORS APPLIED PHYSICS AND MATHEMATICS BUILDING, UNIT 3B 2 ERC 5.1 1 FORUM THEATRE CONTROL ROOM 1 GALBRAITH HALL 3 GEISEL LIBRARY 6 GILMAN PARKING BUILDING # OF ELEVATORS HILLCREST MAIN HOSPITAL 16 HILLCREST AMBULATORY CARE CENTER 2 HILLCREST FACULTY

Tsien, Roger Y.

116

Leaf conductance and carbon gain under salt-stressed conditions  

NASA Astrophysics Data System (ADS)

Exposure of plants to salt stress is often accompanied by reductions in leaf photosynthesis and in stomatal and mesophyll conductances. To separate the effects of salt stress on these quantities, a model based on the hypothesis that carbon gain is maximized subject to a water loss cost is proposed. The optimization problem of adjusting stomatal aperture for maximizing carbon gain at a given water loss is solved for both a non-linear and a linear biochemical demand function. A key novel theoretical outcome of the optimality hypothesis is an explicit relationship between the stomatal and mesophyll conductances that can be evaluated against published measurements. The approaches here successfully describe gas-exchange measurements reported for olive trees (Olea europea L.) and spinach (Spinacia oleraceaL.) in fresh water and in salt-stressed conditions. Salt stress affected both stomatal and mesophyll conductances and photosynthetic efficiency of both species. The fresh water/salt water comparisons show that the photosynthetic capacity is directly reduced by 30%-40%, indicating that reductions in photosynthetic rates under increased salt stress are not due only to a limitation of CO2diffusion. An increase in salt stress causes an increase in the cost of water parameter (or marginal water use efficiency) exceeding 100%, analogous in magnitude to findings from extreme drought stress studies. The proposed leaf-level approach can be incorporated into physically based models of the soil-plant-atmosphere system to assess how saline conditions and elevated atmospheric CO2 jointly impact transpiration and photosynthesis.

Volpe, V.; Manzoni, S.; Marani, M.; Katul, G.

2011-12-01

117

Mass Gains of the Antarctic Ice Sheet Exceed Losses  

NASA Technical Reports Server (NTRS)

During 2003 to 2008, the mass gain of the Antarctic ice sheet from snow accumulation exceeded the mass loss from ice discharge by 49 Gt/yr (2.5% of input), as derived from ICESat laser measurements of elevation change. The net gain (86 Gt/yr) over the West Antarctic (WA) and East Antarctic ice sheets (WA and EA) is essentially unchanged from revised results for 1992 to 2001 from ERS radar altimetry. Imbalances in individual drainage systems (DS) are large (-68% to +103% of input), as are temporal changes (-39% to +44%). The recent 90 Gt/yr loss from three DS (Pine Island, Thwaites-Smith, and Marie-Bryd Coast) of WA exceeds the earlier 61 Gt/yr loss, consistent with reports of accelerating ice flow and dynamic thinning. Similarly, the recent 24 Gt/yr loss from three DS in the Antarctic Peninsula (AP) is consistent with glacier accelerations following breakup of the Larsen B and other ice shelves. In contrast, net increases in the five other DS of WA and AP and three of the 16 DS in East Antarctica (EA) exceed the increased losses. Alternate interpretations of the mass changes driven by accumulation variations are given using results from atmospheric-model re-analysis and a parameterization based on 5% change in accumulation per degree of observed surface temperature change. A slow increase in snowfall with climate waRMing, consistent with model predictions, may be offsetting increased dynamic losses.

Zwally, H. Jay; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui; Brenner, Anita; Bromwich, David

2012-01-01

118

Controlling gain one photon at a time  

PubMed Central

Adaptation is a salient property of sensory processing. All adaptational or gain control mechanisms face the challenge of obtaining a reliable estimate of the property of the input to be adapted to and obtaining this estimate sufficiently rapidly to be useful. Here, we explore how the primate retina balances the need to change gain rapidly and reliably when photons arrive rarely at individual rod photoreceptors. We find that the weakest backgrounds that decrease the gain of the retinal output signals are similar to those that increase human behavioral threshold, and identify a novel site of gain control in the retinal circuitry. Thus, surprisingly, the gain of retinal signals begins to decrease essentially as soon as background lights are detectable; under these conditions, gain control does not rely on a highly averaged estimate of the photon count, but instead signals from individual photon absorptions trigger changes in gain. DOI: http://dx.doi.org/10.7554/eLife.00467.001 PMID:23682314

Schwartz, Gregory W; Rieke, Fred

2013-01-01

119

Tradeoff on gain-flatness and gain-stabilization of erbium doped fiber amplifier with FBGs  

NASA Astrophysics Data System (ADS)

It is a challenge to get gain-stabilization and gain-flatness of erbium doped fiber amplifier (EDFA) in C-band, simultaneously. In this article, we establish a gain-clamped EDFA model based uniform fiber grating-pair and optimize the reflectivity of grating by the designed targets. The tradeoff between stabilization and flatness can be obtained when an ideal reflectivity is adopted. The numerical results show that the gain-stabilization is controlled in +/-0.1dB and gain-flatness is less than +/-1.41dB in the range from 1535nm to 1565nm.

Buyin, Garidi; OuYang, Yunlun; Ma, Yu; Chang, Jinlong; Liu, Changxing; Yang, Jiuru

2014-07-01

120

Experimental Determination of the Gain Distribution of an Avalanche Photodiode at Low Gains  

E-print Network

A measurement system for determining the gain distributions of avalanche photodiodes (APDs) in a low gain range is presented. The system is based on an ultralow-noise charge--sensitive amplifier and detects the output carriers from an APD. The noise of the charge--sensitive amplifier is as low as 4.2 electrons at a sampling rate of 200 Hz. The gain distribution of a commercial Si APD with low average gains are presented, demonstrating the McIntyre theory in the low gain range.

Tsujino, Kenji; Sasaki, Masahide

2008-01-01

121

Experimental Determination of the Gain Distribution of an Avalanche Photodiode at Low Gains  

E-print Network

A measurement system for determining the gain distributions of avalanche photodiodes (APDs) in a low gain range is presented. The system is based on an ultralow-noise charge--sensitive amplifier and detects the output carriers from an APD. The noise of the charge--sensitive amplifier is as low as 4.2 electrons at a sampling rate of 200 Hz. The gain distribution of a commercial Si APD with low average gains are presented, demonstrating the McIntyre theory in the low gain range.

Kenji Tsujino; Makoto Akiba; Masahide Sasaki

2008-12-04

122

Elevation dependency of mountain snow depth  

NASA Astrophysics Data System (ADS)

Elevation strongly affects quantity and distribution patterns of precipitation and snow. Positive elevation gradients were identified by many studies, usually based on data from sparse precipitation stations or snow depth measurements. We present a systematic evaluation of the elevation-snow depth relationship. We analyse areal snow depth data obtained by remote sensing for seven mountain sites near to the time of the maximum seasonal snow accumulation. Snow depths were averaged to 100 m elevation bands and then related to their respective elevation level. The assessment was performed at three scales: (i) the complete data sets (10 km scale), (ii) sub-catchments (km scale) and (iii) slope transects (100 m scale). We show that most elevation-snow depth curves at all scales are characterised through a single shape. Mean snow depths increase with elevation up to a certain level where they have a distinct peak followed by a decrease at the highest elevations. We explain this typical shape with a generally positive elevation gradient of snow fall that is modified by the interaction of snow cover and topography. These processes are preferential deposition of precipitation and redistribution of snow by wind, sloughing and avalanching. Furthermore, we show that the elevation level of the peak of mean snow depth correlates with the dominant elevation level of rocks (if present).

Grünewald, T.; Bühler, Y.; Lehning, M.

2014-12-01

123

CHAPTER 3 EXERCISES Station BS HI FS Elevation Station BS HI FS Elevation  

E-print Network

CHAPTER 3 EXERCISES Station BS HI FS Elevation Station BS HI FS Elevation BM1 595.32' ams BM1 1298 appropriate math checks. Station BS HI FS Elevation Station BS HI FS Elevation BM1 745.32' ams BM1 643.65 ams

Ahmad, Sajjad

124

After-School Exercise Yields Brain Gains  

MedlinePLUS

... regions of the brain gain volume with fitness intervention from studies with older adults," Hillman said, though ... a boost from the exercise -- is critical for positive development, Riggs added. "It's actually more strongly correlated ...

125

Roof Coating Procedures and Their Productivity Gains  

E-print Network

Roof Coating Procedures and their Productivity Gains John Bonaby and Dr. Diane Schaub, University of Florida As building envelope improvements are realized in organizations as ways to insulate businesses from high energy costs, the relative...

Bonaby, J.; Schaub, D.

2006-01-01

126

Operating R.S. Gaines Systems Editor  

E-print Network

Operating R.S. Gaines Systems Editor Cold-Start vs. Warm- Start Miss Ratios Malcolm C. Easton IBM, requires a fee and/or specific permission. Author's present addresses: M.C. Easton, IBM Thomas J. Watson

Fagin, Ron

127

Gain and Phase-margin measurements  

NASA Technical Reports Server (NTRS)

Simple battery-powered test circuit will contribute negligible error when taking open-loop measurements of gain and phase parameters. This is especially helpful when measuring high-grain circuits containing integrators.

Pierce, B. D.

1977-01-01

128

Microwave gain medium with negative refractive index  

NASA Astrophysics Data System (ADS)

Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

2014-12-01

129

Microwave gain medium with negative refractive index.  

PubMed

Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications. PMID:25524752

Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

2014-01-01

130

Deterministic multiplicative gain control with active dendrites.  

PubMed

Multiplicative gain control is a vital component of many theoretical analyses of neural computations, conferring the ability to scale neuronal firing rate in response to synaptic inputs. Many theories of gain control in single cells have used precisely balanced noisy inputs. Such noisy inputs can degrade signal processing. We demonstrate a deterministic method for the control of gain without the use of noise. We show that a depolarizing afterpotential (DAP), arising from active dendritic spike backpropagation, leads to a multiplicative increase in gain. Reduction of DAP amplitude by dendritic inhibition dilutes the multiplicative effect, allowing for divisive scaling of the firing rate. In contrast, somatic inhibition acts in a subtractive manner, allowing spatially distinct inhibitory inputs to perform distinct computations. The simplicity of this mechanism and the ubiquity of its elementary components suggest that many cell types have the potential to display a dendritic division of neuronal output. PMID:16251445

Mehaffey, W Hamish; Doiron, Brent; Maler, Leonard; Turner, Ray W

2005-10-26

131

Universal scaling function for FEL gain  

SciTech Connect

We have developed an analytic calculation of FEL gain in the exponential regime taking into account the finite emittance, energy spread, focusing and betatron oscillation of the electron beam, and the diffraction and guiding of the radiation. The gain is expressed in terms of a universal scaling function with only three independent parameters. Excellent agreement is found with results of numerical simulation. 14 refs., 3 figs., 1 tab.

Yu, L.H.; Krinsky, S. (Brookhaven National Lab., Upton, NY (USA)); Gluckstern, R.L. (Maryland Univ., College Park, MD (USA). Dept. of Physics and Astronomy)

1990-01-01

132

Transient gain dynamics in saturated Raman amplifiers  

Microsoft Academic Search

This paper provides a detailed analysis of transient gain dynamics in saturated Raman amplifiers fed by wavelength division multiplexed (WDM) signals. Such dynamics are due to a pump saturation effect, known as pump-mediated signal-to-signal crosstalk, which is equivalent to the well-known cross-gain modulation in EDFAs. We provide for the first time a simple block-diagram model of the Raman amplifier, whose

A. Bononi; M. Papararo; M. Fuochi

2004-01-01

133

Sudden Gains During Therapy of Social Phobia  

Microsoft Academic Search

The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive–behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967 session-to-session intervals met criteria for sudden gains, which most frequently occurred in Session 5. Individuals

Stefan G. Hofmann; Stefan M. Schulz; Alicia E. Meuret; David A. Moscovitch; Michael Suvak

2006-01-01

134

Gain saturation in phosphate laser glasses  

Microsoft Academic Search

Saturation of gain at 1053 nm was studied in seven Nd-doped phosphate glasses. Values of saturation fluence measured with 1.4-ns pulses were slightly less than those measured with 20-ns pulses. At both pulse lengths, saturation fluence increased with output fluence. For the seven glasses, the product of saturation fluence and gain cross section was constant to within +6 percent.

S. M. Yarema; D. Milam

1982-01-01

135

Vibration Analysis of Elevator Rope  

NASA Astrophysics Data System (ADS)

An elevator rope in a high-rise building is forcibly excited by the displacement of the building caused by earthquakes and wind forces. This paper presents experiments involving free vibration and forced vibration of a rope for obtaining its natural frequency and damping coefficient. Experiments involving forced vibration of a rope whose length varies with time due to the up-and-down movement of a cage are also presented. Finite difference analyses of the rope vibration were performed by considering the time-varying length of the rope, based on the assumption that the movement velocity is constant. The calculated results of the finite difference analyses are in fairly good agreement with the experimental results.

Kimura, Hiroyuki; Iijima, Tomoki; Matsuo, Shigenori; Fujita, Yoshiaki

136

Central gain control in tinnitus and hyperacusis.  

PubMed

Sensorineural hearing loss induced by noise or ototoxic drug exposure reduces the neural activity transmitted from the cochlea to the central auditory system. Despite a reduced cochlear output, neural activity from more central auditory structures is paradoxically enhanced at suprathreshold intensities. This compensatory increase in the central auditory activity in response to the loss of sensory input is referred to as central gain enhancement. Enhanced central gain is hypothesized to be a potential mechanism that gives rise to hyperacusis and tinnitus, two debilitating auditory perceptual disorders that afflict millions of individuals. This review will examine the evidence for gain enhancement in the central auditory system in response to cochlear damage. Further, it will address the potential cellular and molecular mechanisms underlying this enhancement and discuss the contribution of central gain enhancement to tinnitus and hyperacusis. Current evidence suggests that multiple mechanisms with distinct temporal and spectral profiles are likely to contribute to central gain enhancement. Dissecting the contributions of these different mechanisms at different levels of the central auditory system is essential for elucidating the role of central gain enhancement in tinnitus and hyperacusis and, most importantly, the development of novel treatments for these disorders. PMID:25386157

Auerbach, Benjamin D; Rodrigues, Paulo V; Salvi, Richard J

2014-01-01

137

The space station tethered elevator system  

NASA Technical Reports Server (NTRS)

The optimized conceptual engineering design of a space station tethered elevator is presented. The elevator is an unmanned mobile structure which operates on a ten kilometer tether spanning the distance between the Space Station and a tethered platform. Elevator capabilities include providing access to residual gravity levels, remote servicing, and transportation to any point along a tether. The potential uses, parameters, and evolution of the spacecraft design are discussed. Engineering development of the tethered elevator is the result of work conducted in the following areas: structural configurations; robotics, drive mechanisms; and power generation and transmission systems. The structural configuration of the elevator is presented. The structure supports, houses, and protects all systems on board the elevator. The implementation of robotics on board the elevator is discussed. Elevator robotics allow for the deployment, retrieval, and manipulation of tethered objects. Robotic manipulators also aid in hooking the elevator on a tether. Critical to the operation of the tethered elevator is the design of its drive mechanisms, which are discussed. Two drivers, located internal to the elevator, propel the vehicle along a tether. These modular components consist of endless toothed belts, shunt-wound motors, regenerative power braking, and computer controlled linear actuators. The designs of self-sufficient power generation and transmission systems are reviewed. Thorough research indicates all components of the elevator will operate under power provided by fuel cells. The fuel cell systems will power the vehicle at seven kilowatts continuously and twelve kilowatts maximally. A set of secondary fuel cells provides redundancy in the unlikely event of a primary system failure. Power storage exists in the form of Nickel-Hydrogen batteries capable of powering the elevator under maximum loads.

Anderson, Loren A.

1989-01-01

138

Experimental Determination of the Gain Distribution of an Avalanche Photodiode at Low Gains  

Microsoft Academic Search

A measurement system for determining the gain distributions of avalanche photodiodes (APDs) in a low gain range is presented. The system is based on an ultralow-noise charge-sensitive amplifier and detects the output carriers from an APD. The noise of the charge-sensitive amplifier is as low as 4.2 electrons at a sampling rate of 200 Hz. The gain distribution of a

Kenji Tsujino; Makoto Akiba; Masahide Sasaki

2009-01-01

139

Gain and energy storage in holmium YLF  

NASA Technical Reports Server (NTRS)

It is demonstrated that Q-switched holmium lasers are capable of high-gain and high-energy operation at 300 K. Small-signal gain coefficients of 0.50 and 0.12/cm have been measured in YLF and YAG, respectively. Small-signal gains of 0.50/cm are comparable to those achievable in Nd:YAG and are not typical of low-gain materials. This large gain in the Ho:YLF material is made possible by operating the amplifier in the ground state depletion mode. The amplifier performance data and associated analysis presented demonstrate that efficient energy storage is possible with very high excited state ion densities of the Ho 5I7 upper laser level. This is an important result since upconversion can limit the 5I7 population. Although upconversion was still present in this experiment, it was possible to achieve efficient energy storage, demonstrating that the problem is manageable even at high excitation densities in YLF.

Storm, Mark E.; Deyst, John P.

1991-01-01

140

Method and system for edge cladding of laser gain media  

DOEpatents

A gain medium operable to amplify light at a gain wavelength and having reduced transverse ASE includes an input surface and an output surface opposing the input surface. The gain medium also includes a central region including gain material and extending between the input surface and the output surface along a longitudinal optical axis of the gain medium. The gain medium further includes an edge cladding region surrounding the central region and extending between the input surface and the output surface along the longitudinal optical axis of the gain medium. The edge cladding region includes the gain material and a dopant operable to absorb light at the gain wavelength.

Bayramian, Andrew James; Caird, John Allyn; Schaffers, Kathleen Irene

2014-03-25

141

Elevation puts moral values into action  

E-print Network

for the link between elevation and helping behavior was provided by Schnall, Roper, and Fessler (2010). Participants watched an elevating clip from the ‘‘Oprah Winfrey Show’’ in which a music teacher mentored a young man from an impoverished background... it up to the experimenter. Materials Film clips for emotion induction. In the experimental condition, participants watched the 7-minute Oprah Winfrey clip previ- ously used to induce elevation (Silvers & Haidt, 2008; Schnall, Roper, & Fessler, 2010...

Schnall, Simone; Roper, Jean

2011-01-01

142

Ding! Going Up? Elevators and Engineering  

NSDL National Science Digital Library

Students create model elevator carriages and calibrate them, similar to the work of design and quality control engineers. Students use measurements from rotary encoders to recreate the task of calibrating elevators for a high-rise building. They translate the rotations from an encoder to correspond to the heights of different floors in a hypothetical multi-story building. Students also determine the accuracy of their model elevators in getting passengers to their correct destinations.

AMPS GK-12 Program,

143

Changes in wetland sediment elevation following major storms: implications for estimating trends in relative sea-level rise  

USGS Publications Warehouse

Hurricanes can be important agents of geomorphic change in coastal marshes and mangrove forests. Hurricanes can cause large-scale redistribution of sediments within the coastal environment resulting in sedimentation, erosion, disruption of vegetated substrates, or some combination of these processes in coastal wetlands. It has been proposed that such sediment pulsing events are important at maintaining wetland sediment elevations in sediment-poor settings with high rates of relative sea-level rise, such as the Mississippi River Delta. But do these pulsing events result in a net gain in sediment elevation even when substantial amounts of sediment are deposited? Clearly sediment erosion and scour would result in a loss of elevation. But will a substantial sediment deposit on poorly consolidated sediments always result in a net gain in elevation? If the wetland vegetation is killed by wind, tidal surge, or the introduction of saline water, will there be a collapse of sediment elevation in the absence of root production and ongoing decomposition of root matter? During the past decade several wetlands where my colleagues and I have monitored sedimentation and elevation change have been struck by one to several hurricanes. This paper describes the range of sediment elevation responses to hurricane strikes, the suggested mechanisms driving those responses, the implications for estimating long-term trends in relative sea-level rise, and future research needs for improving our understanding of the role that major storms play in wetland sediment elevation dynamics. For many wetlands the change in sediment elevation was directly proportional to the amount of sediment deposited by the storm. But surprisingly, there was a loss of elevation in some wetlands with substantial sediment deposits. In these wetlands, the impact of the storm was either direct (sedimentation and compaction) or indirect (vegetation death), and the effect on sediment elevation was either permanent or temporary. For example, 2 cm of sediment deposited by Hurricane Andrew on a healthy salt marsh in south Louisiana had a direct and positive effect on sediment elevation. But in a deteriorated salt marsh a 3 cm thick sediment deposit was associated with a permanent loss in elevation (we have monitored this site for 10 years). The apparent mechanism driving elevation loss was compaction of the weakened substrate by the weight of the sediment deposit, the storm surge waters, or both. Clearly, storm-related sediment pulses are not going to save this marsh from becoming submerged by rising sea level. A temporary loss in elevation, as much as 2 cm, was observed in a North Carolina salt marsh with a highly organic substrate after each of 3 successive hurricanes even when sediment was deposited. The loss in elevation was apparently related to degassing of the chronically flooded substrate while the rebound in elevation was apparently related to a temporary drawdown of marsh water levels. Interestingly, sediment elevation increased after Hurricane Dennis in 1999, although the increase was less than the thickness of the sediment deposit. Further research is required to determine the mechanisms driving storm-related elevation change (i.e., compaction and expansion) in this marsh. There were two marshes where the gain in sediment elevation was greater than the thickness of the sediment deposit, but the effect was short-lived. In a high salt marsh in southern California, we hypothesize that the temporary spike in elevation was related to the flushing of salts from the hypersaline soils, which enhanced root growth that led to an increase in elevation. In a marsh with a highly organic substrate in north Florida, temporary increases in elevation (as much as 2 cm) greater than the thickness of the sediment deposit were apparently related to groundwater fluxes, which may have been influenced by enhanced runoff from storm rainfall. Lastly, Hurricane Mitch

Cahoon, D.R.

2003-01-01

144

Phase-preserved optical elevator  

PubMed Central

The unique superiority of transformation optics devices designed from coordinate transformation is their capability of recovering both ray trajectory and optical path length in light manipulation. However, very few experiments have been done so far to verify this dual-recovery property from viewpoints of both ray trajectory and optical path length simultaneously. The experimental difficulties arise from the fact that most previous optical transformation optics devices only work at the nano-scale; the lack of intercomparison between data from both optical path length and ray trajectory measurement in these experiments obscured the fact that the ray path was subject to a subwavelength lateral shift that was otherwise not easily perceivable and, instead, was pointed out theoretically [B. Zhang et al. Phys. Rev. Lett. 104, 233903, (2010)]. Here, we use a simple macroscopic transformation optics device of phase-preserved optical elevator, which is a typical birefringent optical phenomenon that can virtually lift an optical image by a macroscopic distance, to demonstrate decisively the unique optical path length preservation property of transformation optics. The recovery of ray trajectory is first determined with no lateral shift in the reflected ray. The phase preservation is then verified with incoherent white-light interferometry without ambiguity and phase unwrapping. PMID:23546046

Luo, Yuan; Zhang, Baile; Han, Tiancheng; Chen, Zhi; Duan, Yubo; Chu, Chia-Wei; Barbastathis, George; Qiu, Cheng Wei

2013-01-01

145

21 CFR 890.3930 - Wheelchair elevator.  

Code of Federal Regulations, 2010 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3930 Wheelchair elevator. (a) Identification. A wheelchair...

2010-04-01

146

21 CFR 890.3930 - Wheelchair elevator.  

Code of Federal Regulations, 2011 CFR

...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3930 Wheelchair elevator. (a) Identification. A wheelchair...

2011-04-01

147

Cascade amps for increased subsystem gain  

NASA Astrophysics Data System (ADS)

Selecting cascadable TO-8 amplifiers integrated onto microstrip circuit boards is considered from the point of view of cascaded circuit design techniques and performance characteristics. Cascaded assemblies and circuit boards used in cascaded-amplifier applications are presented. It is noted that TO-8 package constrains allow as many as three transistor stages per housing, utilizing either passive or active biasing with choke decoupling; these configurations can achieve broadband performance with small-signal gain of 15 to 20 dB. Where higher gain levels are required, TO-8 amplifiers can be cascaded as gain blocks and assembled into aluminum housing with connectors. Increased reflection losses resulting in a higher voltage standing wave ratio are analyzed, along with noise minimization techniques. A model showing how to find a TO-8 amplifier's noise figure, input power, and third-order intercept point is described.

Galla, Timothy J.

1990-05-01

148

Photosynthetic responses to understory shade and elevated carbon dioxide concentration in four northern hardwood tree species.  

PubMed

Seedling responses to elevated atmospheric CO(2) concentration ([CO(2)]) and solar irradiance were measured over two growing seasons in shade-tolerant Acer saccharum Marsh. and Fagus grandifolia J.F. Ehrh. and shade-intolerant Prunus serotina, a J.F. Ehrh. and Betula papyrifera Marsh. Seedlings were exposed to a factorial combination of [CO2] (ambient and elevated (658 micromol mol-1)) and understory shade (deep and moderate) in open-top chambers placed in a forest understory. The elevated [CO(2)] treatment increased mean light-saturated net photosynthetic rate by 63% in the shade-tolerant species and 67% in the shade-intolerant species. However, when measured at the elevated [CO(2)], long-term enhancement of photosynthesis was 10% lower than the instantaneous enhancement seen in ambient-[CO(2)]-grown plants (P < 0.021). Overall, growth light environment affected long-term photosynthetic enhancement by elevated [CO(2)]: as the growth irradiance increased, proportional enhancement due to elevated [CO(2)] decreased from 97% for plants grown in deep shade to 47% for plants grown in moderate shade. Results suggest that in N-limited northern temperate forests, trees grown in deep shade may display greater photosynthetic gains from a CO(2)-enriched atmosphere than trees growing in more moderate shade, because of greater downregulation in the latter environment. If photosynthetic gains by deep-shade-grown plants in response to elevated [CO(2)] translate into improved growth and survival of shade-intolerant species, it could alter the future composition and dynamics of successional forest communities. PMID:17169898

Sefcik, Lesley T; Zak, Donald R; Ellsworth, David S

2006-12-01

149

Superradiance and collective gain in multimode optomechanics  

E-print Network

We present a description of a strongly driven multimode optomechanical system that shows the emergence of cooperative effects usually known from systems of atom-light interaction. Our calculations show that under application of a coherent pump field the system's response can be switched from a superradiant regime to a collective gain regime by varying the frequency detuning of the pump. In the superradiant regime, enhanced optical cooling of a single vibrational mode is possible, whereas the collective gain regime would potentially enable one to achieve almost thresholdless phonon laser action. The threshold pumping power scales as 1/N.

T. Kipf; G. S. Agarwal

2014-09-25

150

Superradiance and collective gain in multimode optomechanics  

NASA Astrophysics Data System (ADS)

We present a description of a strongly driven multimode optomechanical system that shows the emergence of cooperative effects usually known from systems of atom-light interaction. Our calculations show that under application of a coherent pump field the system's response can be switched from a superradiant regime to a collective gain regime by varying the frequency detuning of the pump. In the superradiant regime, enhanced optical cooling of a single vibrational mode is possible, whereas the collective gain regime would potentially enable one to achieve almost thresholdless phonon laser action. The threshold pumping power scales as 1 /N .

Kipf, T.; Agarwal, G. S.

2014-11-01

151

National requirements for improved elevation data  

USGS Publications Warehouse

This report presents the results of surveys, structured interviews, and workshops conducted to identify key national requirements for improved elevation data for the United States and its territories, including coastlines. Organizations also identified and reported the expected economic benefits that would be realized if their requirements for improved elevation were met (appendixes 1–3). This report describes the data collection methodology and summarizes the findings. Participating organizations included 34 Federal agencies, 50 States and two territories, and a sampling of local governments, tribes, and nongovernmental orgnizations. The nongovernmental organizations included The Nature Conservancy and a sampling of private sector businesses. These data were collected in 2010-2011 as part of the National Enhanced Elevation Assessment (NEEA), a study to identify program alternatives for better meeting the Nation’s elevation data needs. NEEA tasks included the collection of national elevation requirements; analysis of the benefits and costs of meeting these requirements; assessment of emerging elevation technologies, lifecycle data management needs, and costs for managing and distributing a national-scale dataset and derived products; and candidate national elevation program alternatives that balance costs and benefits in meeting the Nation’s elevation requirements. The NEEA was sponsored by the National Digital Elevation Program (NDEP), a government coordination body with the U.S. Geological Survey (USGS) as managing partner that includes the National Geospatial-Intelligence Agency (NGA), the Federal Emergency Management Agency (FEMA), the Natural Resources Conservation Service (NRCS), the U.S. Army Corps of Engineers (USACE), and the National Oceanic and Atmospheric Administration (NOAA), among the more than a dozen agencies and organizations. The term enhanced elevation data as used in this report refers broadly to three-dimensional measurements of land or submerged topography, built features, vegetation structure, and other landscape detail. Additional information about NEEA and its later use in the development of a 3D Elevation Program (3DEP) can be found at http://nationalmap.gov/3DEP/index.html.

Snyder, Gregory I.; Sugarbaker, Larry J.; Jason, Allyson L.; Maune, David F.

2014-01-01

152

Cholecystokinin Elevates Mouse Plasma Lipids  

PubMed Central

Cholecystokinin (CCK) is a peptide hormone that induces bile release into the intestinal lumen which in turn aids in fat digestion and absorption in the intestine. While excretion of bile acids and cholesterol into the feces eliminates cholesterol from the body, this report examined the effect of CCK on increasing plasma cholesterol and triglycerides in mice. Our data demonstrated that intravenous injection of [Thr28, Nle31]-CCK at a dose of 50 ng/kg significantly increased plasma triglyceride and cholesterol levels by 22 and 31%, respectively, in fasting low-density lipoprotein receptor knockout (LDLR?/?) mice. The same dose of [Thr28, Nle31]-CCK induced 6 and 13% increases in plasma triglyceride and cholesterol, respectively, in wild-type mice. However, these particular before and after CCK treatment values did not achieve statistical significance. Oral feeding of olive oil further elevated plasma triglycerides, but did not alter plasma cholesterol levels in CCK-treated mice. The increased plasma cholesterol in CCK-treated mice was distributed in very-low, low and high density lipoproteins (VLDL, LDL and HDL) with less of an increase in HDL. Correspondingly, the plasma apolipoprotein (apo) B48, B100, apoE and apoAI levels were significantly higher in the CCK-treated mice than in untreated control mice. Ligation of the bile duct, blocking CCK receptors with proglumide or inhibition of Niemann-Pick C1 Like 1 transporter with ezetimibe reduced the hypercholesterolemic effect of [Thr28, Nle31]-CCK in LDLR?/? mice. These findings suggest that CCK-increased plasma cholesterol and triglycerides as a result of the reabsorption of biliary lipids from the intestine. PMID:23300532

Zhou, Lichun; Yang, Hong; Lin, Xinghua; Okoro, Emmanuel U.; Guo, Zhongmao

2012-01-01

153

20 CFR 416.910 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2011 CFR

20 Employees' Benefits 2 2011-04-01...of substantial gainful activity. 416.910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2011-04-01

154

20 CFR 416.910 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2010 CFR

20 Employees' Benefits 2 2010-04-01...of substantial gainful activity. 416.910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2010-04-01

155

20 CFR 416.910 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2013 CFR

20 Employees' Benefits 2 2013-04-01...of substantial gainful activity. 416.910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2013-04-01

156

20 CFR 404.1510 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2013 CFR

20 Employees' Benefits 2 2013-04-01...of substantial gainful activity. 404.1510 Section...1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2013-04-01

157

20 CFR 416.910 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2012 CFR

20 Employees' Benefits 2 2012-04-01...of substantial gainful activity. 416.910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2012-04-01

158

20 CFR 404.1510 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2014 CFR

20 Employees' Benefits 2 2014-04-01...of substantial gainful activity. 404.1510 Section...1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2014-04-01

159

20 CFR 404.1510 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2010 CFR

20 Employees' Benefits 2 2010-04-01...of substantial gainful activity. 404.1510 Section...1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2010-04-01

160

20 CFR 404.1510 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2012 CFR

20 Employees' Benefits 2 2012-04-01...of substantial gainful activity. 404.1510 Section...1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2012-04-01

161

20 CFR 416.910 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2014 CFR

20 Employees' Benefits 2 2014-04-01...of substantial gainful activity. 416.910 Section 416.910 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2014-04-01

162

20 CFR 404.1510 - Meaning of substantial gainful activity.  

Code of Federal Regulations, 2011 CFR

20 Employees' Benefits 2 2011-04-01...of substantial gainful activity. 404.1510 Section...1510 Employees' Benefits SOCIAL SECURITY ADMINISTRATION...substantial gainful activity. Substantial gainful...significant and productive physical or mental duties;...

2011-04-01

163

GaNWW-oxide metal base transistor with very large current gain and power gain  

E-print Network

GaNÃ?WÃ?W-oxide metal base transistor with very large current gain and power gain K. Mochizuki,a) K 2000 We demonstrate a GaN/W/W-oxide metal base transistor MBT whose collector is formed by oxidizing high due to the difficulty in achieving a high hole concentration and mobility. The metal base

Asbeck, Peter M.

164

RHP: HOW CLIMATE MODELS GAIN AND EXERCISE How Climate Models Gain and Exercise Authority  

E-print Network

49 LHP: HULME RHP: HOW CLIMATE MODELS GAIN AND EXERCISE AUTHORITY 2 How Climate Models Gain and Exercise Authority Mike Hulme Introduction Numerical climate models have become central to the unfolding story of climate change. Climate models underpin the knowledge claims and risk assessments

Hulme, Mike

165

Variable gain for a wind turbine pitch control  

NASA Astrophysics Data System (ADS)

The gain variation is made in the software logic of the pitch angle controller. The gain level is changed depending upon the level of power error. The control uses low gain for low pitch activity the majority of the time. If the power exceeds ten percent offset above rated, the gain is increased to a higher gain to more effectively limit power. A variable gain control functioned well in tests on the Mod-0 wind turbine.

Seidel, R. C.; Birchenough, A. G.

1981-12-01

166

Variable gain for a wind turbine pitch control  

NASA Technical Reports Server (NTRS)

The gain variation is made in the software logic of the pitch angle controller. The gain level is changed depending upon the level of power error. The control uses low gain for low pitch activity the majority of the time. If the power exceeds ten percent offset above rated, the gain is increased to a higher gain to more effectively limit power. A variable gain control functioned well in tests on the Mod-0 wind turbine.

Seidel, R. C.; Birchenough, A. G.

1981-01-01

167

THE KEYS TO GAINING A PRESTIGIOUS SCHOLARSHIP  

E-print Network

THE KEYS TO GAINING A PRESTIGIOUS SCHOLARSHIP START PREPARING EARLY While graduation seems like will be competitive for graduate schools, scholarships, and employers. There are important things that you can do right now to prepare for your future. Graduate schools, scholarship committees, and employers look

Hart, Gus

168

Gainful Employment: The Real Issue. Policy Memo  

ERIC Educational Resources Information Center

Sometimes a proposed piece of legislation or new rule can catalyze debate about a key issue. That seems to be the case for the "gainful employment" rule currently being proposed by the Department of Education (DOE). The rule addresses a very real problem: The large amounts of debt being taken on by some students, mainly those attending for-profit…

Mandel, Michael

2010-01-01

169

Gain scheduled control of magnetic suspension system  

Microsoft Academic Search

A gain scheduling approach for the suspension control of a nonlinear MAGLEV system is presented. We show that this technique is very useful for improving not only performance to the operational disturbances originating aerodynamic force but also robustness to the uncertainty of payload. As a scheduling variable, even though the external disturbance need to be estimated in real time, but

Young Chol Kim; Kook Hun Kim

1994-01-01

170

Sudden Gains during Therapy of Social Phobia  

ERIC Educational Resources Information Center

The present study investigated the phenomenon of sudden gains in 107 participants with social phobia (social anxiety disorder) who received either cognitive-behavioral group therapy or exposure group therapy without explicit cognitive interventions, which primarily used public speaking situations as exposure tasks. Twenty-two out of 967…

Hofmann, Stefan G.; Schultz, Stefan M.; Meuret, Alicia E.; Moscovitch, David A.; Suvak, Michael

2006-01-01

171

Gain International Work Experience in China  

E-print Network

Gain International Work Experience in China www.StudyCLI.org "The CLI internship gave me a huge boost both personally and professionally. At 21 years old, I've lived in China and can speak basic city of Guilin, China. CLIinternsengageinadynamicrangeofprojects: Y Establishnewrelationshipswith

Virginia Tech

172

Mechanisms of the Rosetta high gain antenna  

Microsoft Academic Search

This paper describes the antenna pointing mechanism (APM) and the hold down and release mechanism (HRM) used in the high gain antenna of the ROSETTA mission. The hold down and release mechanism consists of three units which compensate the tolerance mismatch between antenna and spacecraft through incorporation of potting rings. Given that the activation mode is pyrotechnic, release shock is

Carlos Pereira

2001-01-01

173

Gains from cartelisation in the oil market  

Microsoft Academic Search

In this paper we ask whether OPEC still gains from cartelisation in the oil market despite low producer prices and a modest market share. We apply two intertemporal equilibrium models of the global oil market; one consisting of a cartel and a fringe, and one describing a hypothetical competitive market. Comparing the outcome of these models we conclude that there

Elin Berg; Snorre Kverndokk; Knut Einar Rosendahl

1997-01-01

174

Engine improvement and efficiency gained by teamwork  

E-print Network

, the KIVA version of the code was developed as a robust, predictive model of internal combustion engines and customer constraints. The DOE Office of Vehicle Technologies-sponsored Advanced Combustion Engine R- 1 - Engine improvement and efficiency gained by teamwork April 3, 2012 Car companies come calling

175

Gain of a single gas electron multiplier  

NASA Astrophysics Data System (ADS)

Gas Electron Multiplier (GEM) is a gaseous detector used in particle detection and is known for its high rate capability. Ever since its invention in 1997, GEM was applied in many areas and recently has been proposed to be installed in the CMS high ? regions for upgrade at LHC, CERN. A complete understanding of the working and gain behaviour does not exist. GEM gain is influenced by charging up and this has been variedly interpreted in literature lacking consensus. I have attempted in this work through simulations and measurements to achieve a better understanding of single GEM gain and how it is affected by various factors. Specific experimental methods which evolved with subsequent measurements were employed to systematically study the charging up effect. Information from simulations was applied to characterize measurements thereby enabling the development of a model for charging up. Conductivity mechanism of the dielectric used in GEM was analyzed and the resistivity measured. Gain free of charging up effects was measured and this is appropriate for comparison with simulations.

Nemallapudi, Mythra Varun

176

Fuzzy gain scheduling of PID controllers  

Microsoft Academic Search

This paper describes the development of a fuzzy gain scheduling scheme of PID controllers for process control. Fuzzy rules and reasoning are utilized online to determine the controller parameters based on the error signal and its first difference. Simulation results demonstrate that better control performance can be achieved in comparison with Ziegler-Nichols controllers and Kitamori's PID controllers

Zhen-Yu Zhao; Masayoshi Tomizuka; Satoru Isaka

1993-01-01

177

Net Photorefractive Gain In Gallium Arsenide  

NASA Technical Reports Server (NTRS)

Prerequisite includes applied electric field. Electric field applied to GaAs crystal in which two infrared beams interfere. Depending on quality of sample and experimental conditions, net photorefractive gain obtained. Results offer possibility of new developments in real-time optical processing of signals by use of near-infrared lasers of low power.

Liu, Tsuen-Hsi; Cheng, Li-Jen

1990-01-01

178

Pleasure Reading and Reading Rate Gains  

ERIC Educational Resources Information Center

This study investigated the effects of (a) the amount of pleasure reading completed, (b) the type of texts read (i.e., simplified or unsimplified books), and (c) the level of simplified texts read by 14 Japanese university students who made the largest reading rate gains over one academic year. The findings indicated that the participants who made…

Beglar, David; Hunt, Alan

2014-01-01

179

24. 'HANGAR SHEDS ELEVATIONS DETAILS; ARCHITECTURAL PLANS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. 'HANGAR SHEDS - ELEVATIONS - DETAILS; ARCHITECTURAL PLANS - PLANT AREA; MODIFICATION CENTER NO. 1, DAGGETT, CALIFORNIA.' Partial elevations, and details of sliding doors and ventilator flaps, as built. Contract no. W509 Eng. 2743; File no. 555/81, revision B, dated April 6, 1943. No sheet number. - Barstow-Daggett Airport, Hangar Shed No. 4, 39500 National Trails Highway, Daggett, San Bernardino County, CA

180

Contributions to the Elevation North America  

Microsoft Academic Search

Continental elevations result from a combination of buoyancy (i.e. compositional and thermal) and geodynamic forces. Thermal isostasy can produce nearly three kilometers of relief between cold shield platforms and hot rift zones. However, changes in bulk density and crustal thickness can potentially produce relief greater than nine kilometers; whereas, geodynamic contributions to elevation are frequently no greater than a few

D. P. Hasterok; D. S. Chapman; R. N. Harris

2003-01-01

181

75 FR 52868 - Final Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...SUMMARY: Base (1% annual-chance) Flood...No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127...Platte. upstream of Main Street (Base Flood Elevations extend to Bayou...Tributary 3). At Ortego Street (Base +74 Flood Elevations...

2010-08-30

182

Elevated Ozone Alters Soybean-Virus Interaction  

Technology Transfer Automated Retrieval System (TEKTRAN)

We examine the effects of elevated O3 and elevated CO2, two major components of global change, on the interaction between soybean and Soybean Mosaic Virus (SMV) by measuring molecular, cellular, and physiological processes, in natural field conditions and in controlled environment. In natural field ...

183

Sea level and turbidity controls on mangrove soil surface elevation change  

NASA Astrophysics Data System (ADS)

Increases in sea level are a threat to seaward fringing mangrove forests if levels of inundation exceed the physiological tolerance of the trees; however, tidal wetlands can keep pace with sea level rise if soil surface elevations can increase at the same pace as sea level rise. Sediment accretion on the soil surface and belowground production of roots are proposed to increase with increasing sea level, enabling intertidal habitats to maintain their position relative to mean sea level, but there are few tests of these predictions in mangrove forests. Here we used variation in sea level and the availability of sediments caused by seasonal and inter-annual variation in the intensity of La Nina-El Nino to assess the effects of increasing sea level on surface elevation gains and contributing processes (accretion on the surface, subsidence and root growth) in mangrove forests. We found that soil surface elevation increased with mean sea level (which varied over 250 mm during the study) and with turbidity at sites where fine sediment in the water column is abundant. In contrast, where sediments were sandy, rates of surface elevation gain were high, but not significantly related to variation in turbidity, and were likely to be influenced by other factors that deliver sand to the mangrove forest. Root growth was not linked to soil surface elevation gains, although it was associated with reduced shallow subsidence, and therefore may contribute to the capacity of mangroves to keep pace with sea level rise. Our results indicate both surface (sedimentation) and subsurface (root growth) processes can influence mangrove capacity to keep pace with sea level rise within the same geographic location, and that current models of tidal marsh responses to sea level rise capture the major feature of the response of mangroves where fine, but not coarse, sediments are abundant.

Lovelock, Catherine E.; Adame, Maria Fernanda; Bennion, Vicki; Hayes, Matthew; Reef, Ruth; Santini, Nadia; Cahoon, Donald R.

2015-02-01

184

Boreal feather mosses secrete chemical signals to gain nitrogen.  

PubMed

The mechanistic basis of feather moss-cyanobacteria associations, a main driver of nitrogen (N) input into boreal forests, remains unknown. Here, we studied colonization by Nostoc sp. on two feather mosses that form these associations (Pleurozium schreberi and Hylocomium splendens) and two acrocarpous mosses that do not (Dicranum polysetum and Polytrichum commune). We also determined how N availability and moss reproductive stage affects colonization, and measured N transfer from cyanobacteria to mosses. The ability of mosses to induce differentiation of cyanobacterial hormogonia, and of hormogonia to then colonize mosses and re-establish a functional symbiosis was determined through microcosm experiments, microscopy and acetylene reduction assays. Nitrogen transfer between cyanobacteria and Pleurozium schreberi was monitored by secondary ion mass spectrometry (SIMS). All mosses induced hormogonia differentiation but only feather mosses were subsequently colonized. Colonization on Pleurozium schreberi was enhanced during the moss reproductive phase but impaired by elevated N. Transfer of N from cyanobacteria to their host moss was observed. Our results reveal that feather mosses likely secrete species-specific chemo-attractants when N-limited, which guide cyanobacteria towards them and from which they gain N. We conclude that this signalling is regulated by N demands of mosses, and serves as a control of N input into boreal forests. PMID:23795916

Bay, Guillaume; Nahar, Nurun; Oubre, Matthieu; Whitehouse, Martin J; Wardle, David A; Zackrisson, Olle; Nilsson, Marie-Charlotte; Rasmussen, Ulla

2013-10-01

185

Elevated blood pressure in offspring of rats exposed to diverse chemicals during pregnancy.  

PubMed

Adverse intrauterine environments have been associated with increased risk of later cardiovascular disease and hypertension. In an animal model using diverse developmental toxicants, we measured blood pressure (BP), renal nephron endowment, renal glucocorticoid receptor (GR) gene expression, and serum aldosterone in offspring of pregnant Sprague Dawley rats exposed to dexamethasone (Dex), perfluorooctane sulfonate (PFOS), atrazine, perfluorononanoic acid (PFNA), arsenic, or nicotine. BP was assessed by tail cuff photoplethysmography, nephron endowment by confocal microscopy, and renal GR mRNA by qPCR. BP was also measured by telemetry, and corticosterone (CORT) was measured in resting or restrained Dex and atrazine offspring. Treated dams gained less weight during treatment in all groups except arsenic. There were chemical- and sex-specific effects on birth weight, but offspring body weights were similar by weaning. BP was higher in Dex, PFOS, atrazine, and PFNA male offspring by 7-10 weeks. Female offspring exhibited elevated BP at 10 weeks for PFNA and arsenic, and at 37 weeks for Dex, PFOS, and atrazine. Dex, PFOS, and atrazine offspring still exhibited elevated BP at 52-65 weeks of age; others did not. Elevated BP was associated with lower nephron counts. Dex, PFOS, and atrazine offspring had elevated renal GR gene expression. Elevations in BP were also observed in Dex and atrazine offspring by radiotelemetry. Atrazine offspring exhibited enhanced CORT response to restraint. Elevated offspring BP was induced by maternal exposure to toxicants. Because all treatments affected maternal gestational weight gain, maternal stress may be a common underlying factor in these observations. PMID:24218149

Rogers, John M; Ellis-Hutchings, Robert G; Grey, Brian E; Zucker, Robert M; Norwood, Joel; Grace, Curtis E; Gordon, Christopher J; Lau, Christopher

2014-02-01

186

Gain scheduled control of hysteretic systems  

NASA Astrophysics Data System (ADS)

This paper addresses tracking-control of hysteretic systems using a gain-scheduled (GS) controller. Hysteretic system with variable stiffness and damping is represented as a quasi linear parameter varying (LPV) system. Designed controller is scheduled on the measured/estimated stiffness and damping in real-time. GS controller is constructed from the parameter dependent Lyapunov matrices, which are obtained as optimal solutions of linear matrix inequalities (LMIs) that ensures the feasibility solution for closed loop system performance. The proposed method is worked on semiactive independently variable stiffness (SAIVS) device. It is shown that the gain-scheduled controller developed for the quasi-LPV system results in excellent tracking performance even in the cases where robust-H? controller failed to function.

Pasala, Dharma Theja R.; Nagarajaiah, Satish; Grigoriadis, Karolos

2009-03-01

187

Gain coupling of class A semiconductor lasers.  

PubMed

We report on the development of a gain-coupled class A semiconductor laser for dual-wavelength generation via optical switching. A vertical external cavity surface emitting laser (VECSEL) structure is used, because it provides a flexible platform for high-power, high-brightness output in the near-IR and visible ranges. For the first time (to our knowledge), two VECSEL cavities sharing a common gain region are studied. Because the cavities are in competition for common carriers, birefringent filters in the external cavity control the laser cavity thresholds; this configuration demonstrates the possibility of switching between the two cavities, which can operate at different wavelengths. However, in this Letter we also show, numerically and experimentally, that with the consideration of spontaneous emission, it is possible to maintain simultaneous lasing in each cavity at a different wavelength. PMID:20847778

Hessenius, Chris; Terry, Nathan; Fallahi, Mahmoud; Moloney, Jerome; Bedford, Robert

2010-09-15

188

Gain scaling for multirate filter banks  

SciTech Connect

Eliminating two trivial degrees of freedom corresponding to the lowpass DC response and the highpass Nyquist response in a two-channel multirate filter bank seems simple enough. Nonetheless, the ISO/IEC JPEG 2000 image coding standard manages to make this mundane task look totally mysterious. We reveal the true meaning behind JPEG 2000's arcane specifications for filter bank normalization and point out how the seemingly trivial matter of gain scaling leads to highly nontrivial issues concerning uniqueness of lifting factorizations.

Brislawn, Christopher M [Los Alamos National Laboratory

2009-01-01

189

Gain scheduled control of hysteretic systems  

Microsoft Academic Search

This paper addresses tracking-control of hysteretic systems using a gain-scheduled (GS) controller. Hysteretic system with variable stiffness and damping is represented as a quasi linear parameter varying (LPV) system. Designed controller is scheduled on the measured\\/estimated stiffness and damping in real-time. GS controller is constructed from the parameter dependent Lyapunov matrices, which are obtained as optimal solutions of linear matrix

Dharma Theja R. Pasala; Satish Nagarajaiah; Karolos Grigoriadis

2009-01-01

190

Development of high gain GEM detectors  

E-print Network

We describe systematic measurements carried out with single and double GEM detectors with printed circuit readout. The maximum safe operating gain has been measured at increasing radiation flux and under exposure to heavily ionizing tracks. Detection efficiency, localization accuracy and cluster size have been measured in a minimum ionizing particle beam. With a suitably configured readout electrode, fast, two-dimensional localization of radiation is demonstrated. (15 refs).

Bressan, A; Sauli, Fabio; Mörmann, D

2000-01-01

191

The Comstar D/3 gain degradation experiment  

NASA Technical Reports Server (NTRS)

The results of gain degradation measurements using the Comstar D/3 19.04 GHz beacon are reported. This experiment utilized 0.6 and 5 m aperture antennas aligned along the same propagation path to examine propagation effects which are related to the antenna aperture size. Sample data for clear air, scintillation in clear air, and precipitation fading are presented. Distributions of the received signal levels and variances for both antennas are also presented.

Lee, T. C.; Hodge, D. B.

1981-01-01

192

High Gain Fast Ignition Point Design  

Microsoft Academic Search

The fast ignition (FI) approach to inertial confinement fusion offers the potential for achieving the high target gains required for Inertial Fusion Energy (IFE). In FI a D-T fuel capsule is first compressed via a quasi-isochoric implosion to form a high density core, and then ignited with a short-pulse laser-generated relativistic electron beam. This paper reports progress on the development

P. K. Patel; P. Amendt; C. D. Chen; D. Clark; B. Cohen; D. S. Hey; L. Divol; D. Higginson; D. Ho; D. Homoelle; A. J. Kemp; M. H. Key; D. Larson; B. Lasinski; S. Le Pape; T. Ma; H. McLean; D. J. Meeker; Y. Ping; H. Shay; D. J. Strozzi; M. Tabak; R. P. J. Town; B. Westover; S. C. Wilks

2010-01-01

193

IQ Gains in Argentina between 1964 and 1998  

ERIC Educational Resources Information Center

The literature on IQ gains in Latin America is sparse. We estimate gains on Raven's Progressive Matrices in the city of La Plata (Argentina) between 1964 and 1998. The gains are robust at the top of the curve as well as at the bottom. Therefore, they are contrary to the hypothesis that nutrition played a major role in recent Argentine IQ gains.…

Flynn, James R.; Rossi-Case, Lilia

2012-01-01

194

Modal analysis of a planar waveguide with gain and losses  

Microsoft Academic Search

In this study, we analyze the waveguiding properties of a planar waveguide amplifier in which losses and gain can be present simultaneously. It is found that the subsequent modes comprise both loss and gain modes. Also, the dependence of the gain on the state of polarization turns out to be significant for realistic dielectric structures. For strong losses or gain,

T. D. Visser; H. Blok; D. Lenstra

1995-01-01

195

Effects of Gain Changes on RPM Performance  

SciTech Connect

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity gains are less than 5% (Fig. 6). ORNL does not consider this slight increase in sensitivity to be a worthwhile pursuit. Second, increasing the ULD will increase sensitivity a few percent (Fig. 7); however, it is not clear that the slight increase in sensitivity is worth the effort required to make the change (e.g., reliability, cost, etc.). Additionally, while the monitor would be more sensitive to HEU, it would also be more sensitive to NORM. Third, the sensitivity of the system remains approximately the same whether it is calibrated to a small source on contact or a large source far away (Fig. 6). This affirms that no changes to the existing calibration procedure are necessary.

Lousteau, Angela L [ORNL; York, Robbie Lynn [ORNL; Livesay, Jake [ORNL

2012-03-01

196

The effect of holiday weight gain on body weight.  

PubMed

The topic of holiday weight gain has been a frequent subject of the lay media; however, scientific interest has only been recent. Multiple studies in Western societies have reported average weight gains among adults during the period between mid-November and mid-January that were about 0.5 kg. The range in individual weight changes was large, however, and the already overweight and obese gain more weight than those who are healthy weight. When the average gain across the year was also measured, the holiday weight was the major contributor to annual excess weight gain. Efforts patterned to increase awareness to energy balance and body weight have been shown to be successful at reducing such gain. An exception to holiday weight gain being a major contributor to annual excess gain has been children, in whom summer weight gains have been observed to be the major contributor to average excess weight gain. PMID:24662697

Schoeller, Dale A

2014-07-01

197

Robust Gain-Scheduled Fault Tolerant Control for a Transport Aircraft  

NASA Technical Reports Server (NTRS)

This paper presents an application of robust gain-scheduled control concepts using a linear parameter-varying (LPV) control synthesis method to design fault tolerant controllers for a civil transport aircraft. To apply the robust LPV control synthesis method, the nonlinear dynamics must be represented by an LPV model, which is developed using the function substitution method over the entire flight envelope. The developed LPV model associated with the aerodynamic coefficient uncertainties represents nonlinear dynamics including those outside the equilibrium manifold. Passive and active fault tolerant controllers (FTC) are designed for the longitudinal dynamics of the Boeing 747-100/200 aircraft in the presence of elevator failure. Both FTC laws are evaluated in the full nonlinear aircraft simulation in the presence of the elevator fault and the results are compared to show pros and cons of each control law.

Shin, Jong-Yeob; Gregory, Irene

2007-01-01

198

Perinatal Tumor Necrosis Factor-? Production, Influenced by Maternal Pregnancy Weight Gain, Predicts Childhood Asthma  

PubMed Central

Rationale: Innate immune responses marked by increases in tumor necrosis factor (TNF)-? have been associated with asthma but whether such alterations are evident before symptoms is not yet clear. Objectives: To determine if prevalence of childhood asthma or asthma-related traits is predicted by perinatal innate immune status and if maternal factors related to pregnancy influence asthma prevalence and innate immune status. Methods: In the Tucson Infant Immune Study (a nonselected birth cohort), presence of eczema and wheezing in the child's first year and physician-diagnosed asthma through age 9 and asthma in the parents was obtained from parent-completed questionnaires. TNF-?, IL-6, IL-10, and IL-12 were measured in supernatants of LPS-stimulated peripheral blood mononuclear cells at birth and 3 months as was TNF-? in plasma. TNF-? single nucleotide polymorphisms were genotyped by Sequenom. Percent predicted FEV1/FVC was measured at age 9. Maternal weight gain during pregnancy and prepregnancy weight were ascertained from medical records. Measurements and Main Results: Infants with persistently elevated LPS-induced TNF-? at birth and 3 months were at increased risk for childhood asthma (odds ratio [OR], 4.1; confidence interval [CI], 1.9–8.8; n = 233; P = 0.0003) and had decreased FEV1/FVC ratios at age 9. Children with mothers in the top tertile for pregnancy weight gain had increased risk for asthma (OR, 3.4; CI, 1.7–6.9; n = 225; P = 0.001) and persistently elevated TNF-? in early life (OR, 2.9; CI, 1.4–8.2; n = 195; P = 0.013). These relations were independent of maternal asthma and rhinitis. Conclusions: Persistently elevated LPS-induced TNF-? production early in life acts as a predictive biomarker for childhood asthma, and excess pregnancy weight gain in the mother seems to contribute to both. PMID:23590270

Lohman, I. Carla; Stern, Debra A.; Ellis, Whitney L.; Rothers, Janet; Wright, Anne L.

2013-01-01

199

77 FR 73398 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...elevations, and communities affected for Webster County, Kentucky, and Incorporated Areas...CFR 67.4. The table, entitled ``Webster County, Kentucky, and Incorporated Areas...Webster County, Kentucky, and Incorporated...

2012-12-10

200

Polyetheretherketone Membranes for Elevated Temperature PEMFCs  

E-print Network

Polyetheretherketone Membranes for Elevated Temperature PEMFCs Balasubramanian Lakshmanan. To enable high-temperature PEMFC operation, membranes that have better water retention capability, higher Power Incorporated, Latham, New York 12110, USA c Polyfuel, Menlo Park, California 94025, USA Membrane

Weidner, John W.

201

77 FR 74142 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...elevations, and communities affected for Iron County, Utah, and Incorporated Areas...CFR 67.4. The tables, entitled ``Iron County, Utah, and Incorporated Areas...Iron County, Utah, and Incorporated...

2012-12-13

202

3D Elevation Program: summary for Vermont  

USGS Publications Warehouse

The National Enhanced Elevation Assessment evaluated multiple elevation data acquisition options to determine the optimal data quality and data replacement cycle relative to cost to meet the identified requirements of the user community. The evaluation demonstrated that lidar acquisition at quality level 2 for the conterminous United States and quality level 5 interferometric synthetic aperture radar (ifsar) data for Alaska with a 6- to 10-year acquisition cycle provided the highest benefit/cost ratios. The 3D Elevation Program (3DEP) initiative selected an 8-year acquisition cycle for the respective quality levels. 3DEP, managed by the U.S. Geological Survey, the Office of Management and Budget Circular A–16 lead agency for terrestrial elevation data, responds to the growing need for high-quality topographic data and a wide range of other 3D representations of the Nation’s natural and constructed features.

Carswell, William J., Jr.

2015-01-01

203

3D Elevation Program: summary for Nebraska  

USGS Publications Warehouse

The National Enhanced Elevation Assessment evaluated multiple elevation data acquisition options to determine the optimal data quality and data replacement cycle relative to cost to meet the identified requirements of the user community. The evaluation demonstrated that lidar acquisition at quality level 2 for the conterminous United States and quality level 5 interferometric synthetic aperture radar (ifsar) data for Alaska with a 6- to 10-year acquisition cycle provided the highest benefit/cost ratios. The 3D Elevation Program (3DEP) initiative selected an 8-year acquisition cycle for the respective quality levels. 3DEP, managed by the U.S. Geological Survey, the Office of Management and Budget Circular A–16 lead agency for terrestrial elevation data, responds to the growing need for high-quality topographic data and a wide range of other 3D representations of the Nation’s natural and constructed features.

Carswell, William J., Jr.

2015-01-01

204

Compensated gain control circuit for buck regulator command charge circuit  

DOEpatents

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

Barrett, D.M.

1996-11-05

205

Antenna Gain Enhancement and Beamshaping using a Diffractive Optical Element (DOE) Lens  

NASA Astrophysics Data System (ADS)

Dielectric and metamaterial lenses have been designed for gain enhancement and beam shaping. The motivation for this work came from a commercially available slotted waveguide antenna with a dielectric lens that shapes the beam and enhances the gain only in the azimuth plane. When two of these antennas, each with a dielectric lens, are stacked as an array to form the sum and difference patterns the elevation plane gain is low and the beam width too wide to be acceptable for radar applications. The objective of the present work is to design a diffractive optical element (DOE) lens for gain enhancement gain and beam shaping. As compared to other available lenses it is much thinner, lighter and easily machined. The DOE lens is made from rexolite which has a dielectric constant of 2.53. The DOE lens is composed of a series of zones which focus the light at a certain focal length. The phase is the same everywhere on each zone at the focal point. The phase difference between neighboring zones is 2pi, resulting in a constructive interference at the focus. These zones are able to focus the radiation from an antenna in order to enhance the gain and shape the beam. The design parameters include the lens diameter, number of zones, the center zone thickness for a particular frequency and refractive index of the dielectric material. A comprehensive study has been performed in CST Microwave Studio to illustrate the properties of the DOE lens. The focusing property for image formation is verified by a plane wave excitation. Lenses have been designed and tested at different frequencies and with varying design parameters. Gain enhancement and beam shaping are illustrated by modeling the DOE lens in CST and placing it in front of different antennas. This work presents lenses for 10GHz and 40GHz horn antennas, a 3GHz slotted waveguide antenna array, and a 10GHz microstrip patch arrays. Beam shaping and focusing is clearly illustrated for each type of antenna. It is seen that the size of the lens is directly proportional to gain increase which can be as high 20dB enhancement for a 40-GHz horn antenna. The 3GHz DOE lens illustrates for the slotted waveguide array, a gain enhancement of 7dB in the elevation plane, as well as decrease of the 3dB beamwidth from 20° to 13.5°. It is also proved that the DOE lens allows for the creation of a good difference pattern. Experimental validation for the focusing properties and the gain enhancement has been done using the 10GHz DOE, made from rexolite, and fabricated using CNC milling in the RIT Brinkman Lab. The image formation has been verified using an electric field probing station in the Nanoplasmonic lab at RIT. Two types of excitation have been done with a dipole and with a horn antenna, where another dipole probes the field in the transmission plane. The electric field intensity shows clearly the beam focusing by the DOE lens. The X-band anechoic chamber in the Electromagnetics Theory and Application (ETA) lab has been used to demonstrate the gain enhancement of a horn antenna with the fabricated DOE lens. The distance of the lens from the receive antenna has been varied to obtain a maximum received power. The results show a substantial gain enhancement of 6.6 dB for the horn antenna and of 5.6 dB for the patch array.

Torbitt, Christopher

206

HYDRO 1K Elevation Derivative Database  

NSDL National Science Digital Library

The Earth Resources Observation Systems' Data Center at the US Geological Survey developed this database from the 30 arc-second digital elevation model of the world. The database contains six raster data sets in tar file format: elevation data, shaded relief, slope, aspect, flow direction, and flow accumulation; and two vector data sets in tar or gzipped ARC/INFO Export file formats: drainage basins and streams.

1998-01-01

207

Elevator Illusion and Gaze Direction in Hypergravity  

NASA Technical Reports Server (NTRS)

A luminous visual target in a dark hypergravity (Gz greater than 1) environment appears to be elevated above its true physical position. This "elevator illusion" has been attributed to changes in oculomotor control caused by increased stimulation of the otolith organs. Data relating the magnitude of the illusion to the magnitude of the changes in oculomotor control have been lacking. The present study provides such data.

Cohen, Malcolm M.; Hargens, Alan (Technical Monitor)

1995-01-01

208

Airborne mycotoxins in dust from grain elevators  

Microsoft Academic Search

Workers in grain elevators are exposed to grain dust and may therefore have an increased risk of inhalatory contact with mycotoxins.\\u000a To study the mycotoxin burden of such environments, settled grain dust samples (n=35) were collected from several locations\\u000a of a total of 13 grain elevators in Germany, and analysed for ochratoxin A (OTA, detection limit 0.01 ng\\/g), deoxynivalenol\\u000a (DON,

S. Mayer; V. Curtui; E. Usleber; M. Gareis

2007-01-01

209

Do we intervene inappropriately for ST elevation?  

PubMed Central

ST elevation on a 12 lead ECG is one of the cardinal features of acute myocardial infarction (AMI), yet it also occurs with other clinical conditions such as spontaneous pneumothorax. Three cases are presented, all of whom had chest pain and ST elevation. All had pneumothoraces yet only one had an AMI. Thrombolysis was administered to one patient. With the current pressure on "door?to?needle" times, emergency physicians should take care to differentiate between these entities. PMID:16439724

Sanders, A; Froude, A; Probst, F

2006-01-01

210

Design and implementation of the CAN based elevator control system  

Microsoft Academic Search

In this paper we present a design and implementation of a modern elevator control system. The conventional elevator control system has several disadvantages (complicated circuits, a large number of wires, sensitivity to noise, low level security, etc). An alternative to conventional elevator control systems is a distributed elevator control system. This paper describes a network-based elevator control system via controller

Senad Huseinbegovic; Sead Kreso; Omer Tanovic

2009-01-01

211

Sudden Gains during Cognitive Behavioral Group Therapy for Anxiety Disorders  

PubMed Central

Sudden gains in psychotherapy are characterized by large and relatively stable decreases in psychiatric symptoms and have been associated with cognitive shifts in clients and shown to predict superior treatment outcomes in studies of depression and, to a lesser extent, anxiety disorders. The purpose of this study was to examine prevalence and impact of sudden gains during a transdiagnostic cognitive-behavioral group therapy (CBGT) for anxiety disorders, as well as the temporal relationship between sudden gains and cognitive changes. Data were used from two trials of transdiagnostic CBGT for anxiety disorders (n = 130). Criteria for determining sudden gains in anxiety symptoms were based upon previous research on sudden gains from trials of cognitive behavioral treatments for major depressive disorder. A total of 17 out of 98 (17.3%) clients experienced at least one sudden gain, with three clients showing two sudden gains during treatment. Three patients showing a sudden gain experienced a reversal of these gains, although one of these three had a subsequent second sudden gain. Clients experiencing sudden gains showed greater overall improvement following treatment than did clients who did not experience a sudden gain, with 65% of the sudden gainers' overall improvement accounted for by the sudden gain. Greater cognitive change in the pregain sessions was observed for clients with a sudden gain than those not showing a sudden gain. This finding lends support to the theory of cognitive mediation through CBGT in which substantial cognitive changes in pregain sessions lead to greater improvement overall. PMID:20621441

Norton, Peter J.; Klenck, Suzanne C.; Barrera, Terri L.

2010-01-01

212

Gravity aided inertial navigation system (GAINS)  

NASA Astrophysics Data System (ADS)

The paper describes a new autonomous covert INS uniquely suited to underwater applications. Unlike the conventional INS, schuler and siderial errors are bounded without external navigation aids or active instrumentation of ground speed. As a result, the system exhibits excellent long-term navigation performance while maintaining the inherent covertness of the INS system. A conventional INS is integrated with a gravity gradiometer capable of measuring gravity field components independently of platform accelerations. This new integration scheme takes advantage of navigation system velocity error observability. Parametric performance results are presented for GAINS, varying gyro, gravimeter, gradiometer, depth sensor quality, and gravity field activity.

Jircitano, Albert; Dosch, Daniel E.

213

Capital gains tax treatment and the cattleman  

E-print Network

77 78 79 TABLE OF CONTENTS (continued) CHAPTER Vl. SUMMARY AND CONCLUSIONS Page 8O Summary Opt imal replacement pol i c ies After-tax advantages of capital gain income Conclusions Fulfii lment of objectives General comments 81 82 91... eventual ly diminishes. The fol lowing percentages were estimated in an attempt to measure this factor of reproduction: a fD ~(ci 1 Y ) W *d ~C ~ 1 1 ~pt * 70 ( 2) 80 ( 3) 85 ( 4) 90 (5) 95 95 ( 7) 95 ( 8) 95 10 ( 9) 95 (i 0) 92 12 90 Cow...

Rister, M. Edward

1976-01-01

214

Coherence Related Gain Phenomena in Potassium -  

NASA Astrophysics Data System (ADS)

This work focuses on the theoretical and experimental investigations of coherence related gain phenomena in a collisionally assisted, four-level Raman-driven system, where atomic collisions provide incoherent population to the probed excited state. The theory, as originally envisioned by Narducci and coworkers(1) (without collisions), is first introduced and discussed. Modifications to this theory are made to allow for the addition of atomic collision processes, including dephasing, incoherent transfer of excited state population, and transit relaxation. The modified theory is then applied to a model system simulating a potassium-(noble gas) mixture. Examination of this model reveals several features, including: (1) inversionless amplification of a probe beam is possible; (2) helium is the best choice of buffer gas to facilitate the collisional transfer of excited state population, while at the same time minimizing the undesirable relaxation of coherences due to dephasing; and (3) a copropagating pump/probe geometry is best for optimum results. In addition, it is found that many of these theoretical results can also be found in a three-level V configuration with collisional transfer used to populate the probed excited state. Time-dependent and time-independent methods of distinguishing between the two theoretical systems are discussed. The experimental realization of this system in potassium-helium and potassium-argon mixtures, with strong laser pumping and weak probing on the potassium D lines, shows good agreement with the Block equation theoretical analysis of a four-level model using realistic atomic parameters. Gain and altered absorption profiles are observed and compare well with theory. The experimental gain behavior with respect to pump power supports the four-level model over the three-level model. The experiments are insensitive to relative pump/probe linear polarizations. Measurements of atomic energy level populations for a strongly driven 14.2 torr helium-potassium mixture, demonstrating gain for line center pumping, are conducted and discussed. The measured relative populations for this case are: n(4P _{1/2})/n_{ rm total} =.0982 +/-.034; and n(4P_{3/2})/n _{rm total} =.193 +/-.083. These measurements imply that the probed level 4P_{1/2} population is not inverted with respect to the ground state. ftn(1) L. M. Narducci, H. M. Doss, P. Ru, M. O. Scully, S. Y. Zhu, and C. Keitel, Opt. Commun. 81, 379 (1991).

Kleinfeld, Jeffrey A.

1995-01-01

215

Characterization of ultrasound elevation beamwidth artifacts for prostate brachytherapy needle insertion  

SciTech Connect

Purpose: Ultrasound elevation beamwidth leads to image artifacts and uncertainties in localizing objects (such as a surgical needle) in ultrasound images. The authors examined the clinical significance of errors caused by elevation beamwidth artifacts and imaging parameters in needle insertion procedures. Methods: Beveled prostate brachytherapy needles were inserted through all holes of a grid template under real-time transrectal ultrasound (TRUS) guidance. The needle tip position as indicated by the TRUS image was compared to their observed physical location. A new device was developed to measure the ultrasound elevation beamwidth. Results: Imaging parameters of the TRUS scanner have direct impact on the localization error ranging from 0.5 up to 4 mm. The smallest localization error was observed laterally close to the center of the grid template and axially within the beam's focal zone. Largest localization error occurs laterally around both sides of the grid template and axially within the beam's far field. The authors also found that the localization errors vary with both lateral and elevation offsets. Conclusions: The authors found properly adjusting the TRUS imaging settings to lower the ultrasound gain and power effectively minimized the appearance of elevation beamwidth artifacts and in turn reduced the localization errors of the needle tip.

Peikari, Mohammad; Chen, Thomas Kuriran; Lasso, Anras; Heffter, Tamas; Fichtinger, Gabor; Burdette, Everette C. [Laboratory for Percutaneous Surgery (Perk), School of Computing, Queen's University, Kingston, Ontario K7L 3N6 (Canada); Acoustic MedSystems, 208 Burwash Avenue, Savoy, Illinois 61874 (United States)

2012-01-15

216

29 CFR 1918.87 - Ship's cargo elevators.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Ship's cargo elevators. 1918.87 Section...LONGSHORING Handling Cargo § 1918.87 Ship's cargo elevators. (a) Safe working load. The safe working loads of ship's cargo elevators shall be...

2014-07-01

217

49 CFR 213.59 - Elevation of curved track; runoff.  

Code of Federal Regulations, 2013 CFR

...Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.59 Elevation of curved track; runoff. (a) If a curve is elevated, the full elevation shall be...

2013-10-01

218

49 CFR 213.59 - Elevation of curved track; runoff.  

Code of Federal Regulations, 2012 CFR

...Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.59 Elevation of curved track; runoff. (a) If a curve is elevated, the full elevation shall be...

2012-10-01

219

49 CFR 213.59 - Elevation of curved track; runoff.  

Code of Federal Regulations, 2010 CFR

...Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.59 Elevation of curved track; runoff. (a) If a curve is elevated, the full elevation shall be...

2010-10-01

220

49 CFR 213.59 - Elevation of curved track; runoff.  

Code of Federal Regulations, 2011 CFR

...Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.59 Elevation of curved track; runoff. (a) If a curve is elevated, the full elevation shall be...

2011-10-01

221

49 CFR 172.325 - Elevated temperature materials.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Elevated temperature materials. 172.325 Section 172...PLANS Marking § 172.325 Elevated temperature materials. (a) Except as provided...bulk packaging containing an elevated temperature material must be marked on two...

2011-10-01

222

49 CFR 172.325 - Elevated temperature materials.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Elevated temperature materials. 172.325 Section 172...PLANS Marking § 172.325 Elevated temperature materials. (a) Except as provided...bulk packaging containing an elevated temperature material must be marked on two...

2014-10-01

223

49 CFR 172.325 - Elevated temperature materials.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Elevated temperature materials. 172.325 Section 172...PLANS Marking § 172.325 Elevated temperature materials. (a) Except as provided...bulk packaging containing an elevated temperature material must be marked on two...

2012-10-01

224

49 CFR 172.325 - Elevated temperature materials.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Elevated temperature materials. 172.325 Section 172...PLANS Marking § 172.325 Elevated temperature materials. (a) Except as provided...bulk packaging containing an elevated temperature material must be marked on two...

2013-10-01

225

49 CFR 172.325 - Elevated temperature materials.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Elevated temperature materials. 172.325 Section 172...PLANS Marking § 172.325 Elevated temperature materials. (a) Except as provided...bulk packaging containing an elevated temperature material must be marked on two...

2010-10-01

226

5. VIEW OF SECOND ELEVATOR WITH WOODFRAME HEADHOUSE AND ASPHALTIC ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF SECOND ELEVATOR WITH WOOD-FRAME HEADHOUSE AND ASPHALTIC SIDING, LOOKING WEST. - Lockport DuPage Farmer's Elevator Company Grain Elevator, South of Romeoville Road, Lockport, Will County, IL

227

23. Elevator no. 2: floor 4, with control shafts and ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. Elevator no. 2: floor 4, with control shafts and turnhead distributors, east wall of control room (floor 5, elevated) in background, facing southwest - Washburn Crosby Company Elevators No. 2 & 3, 900 & 1000 Second Avenue, South, Minneapolis, Hennepin County, MN

228

14 CFR 23.155 - Elevator control force in maneuvers.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Elevator control force in maneuvers. 23.155 Section...Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force needed to achieve the...

2013-01-01

229

14 CFR 23.155 - Elevator control force in maneuvers.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Elevator control force in maneuvers. 23.155 Section...Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force needed to achieve the...

2012-01-01

230

Waseda University Doctoral Dissertation Elevator Group Supervisory Control of  

E-print Network

Waseda University Doctoral Dissertation Elevator Group Supervisory Control of Double-Deck and Multi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Overview of Elevator Group Supervisory Control System (EGSCS) . . . . . . 1.2.1 Development History of Elevator Systems . . . . . . . . . . . . . . . . . 1.2.2 Control Algorithms

Fernandez, Thomas

231

14 CFR 23.155 - Elevator control force in maneuvers.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Elevator control force in maneuvers. 23.155 Section...Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force needed to achieve the...

2011-01-01

232

14 CFR 23.155 - Elevator control force in maneuvers.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 2014-01-01 false Elevator control force in maneuvers. 23.155 Section...Controllability and Maneuverability § 23.155 Elevator control force in maneuvers. (a) The elevator control force needed to achieve the...

2014-01-01

233

Effects of prescribed burning on marsh-elevation change and the risk of wetland loss  

USGS Publications Warehouse

Marsh-elevation change is the net effect of biophysical processes controlling inputs versus losses of soil volume. In many marshes, accumulation of organic matter is an important contributor to soil volume and vertical land building. In this study, we examined how prescribed burning, a common marsh-management practice, may affect elevation dynamics in the McFaddin National Wildlife Refuge, Texas by altering organic-matter accumulation. Experimental plots were established in a brackish marsh dominated by Spartina patens, a grass found throughout the Gulf of Mexico and Atlantic marshes. Experimental plots were subjected to burning and nutrient-addition treatments and monitored for 3.5 years (April 2005 – November 2008). Half of the plots were burned once in 2006; half of the plots were fertilized seasonally with nitrogen, phosphorus, and potassium. Before and after the burns, seasonal measurements were made of soil physicochemistry, vegetation structure, standing and fallen plant biomass, aboveground and belowground production, decomposition, and accretion and elevation change (measured with Surface Elevation Tables (SET)). Movements in different soil strata (surface, root zone, subroot zone) were evaluated to identify which processes were contributing to elevation change. Because several hurricanes occurred during the study period, we also assessed how these storms affected elevation change rates. The main findings of this study were as follows: 1. The main drivers of elevation change were accretion on the marsh surface and subsurface movement below the root zone, but the relative influence of these processes varied temporally. Prior to Hurricanes Gustav and Ike (September 2008), the main driver was subsurface movement; after the hurricane, both accretion and subsurface movement were important. 2. Prior to Hurricanes Gustav and Ike, rates of elevation gain and accretion above a marker horizon were higher in burned plots compared to nonburned plots, whereas nutrient addition had no detectable influence on elevation dynamics. 3. Burning decreased standing and fallen plant litter, reducing fuel load. Hurricanes Gustav and Ike also removed fallen litter from all plots. 4. Aboveground and belowground production rates varied annually but were unaffected by burning and nutrient treatments. 5. Decomposition (of a standard cellulose material) in upper soil layers was increased in burned plots but was unaffected by nutrient treatments. 6. Soil physicochemistry was unaffected by burning or nutrient treatments. 7. The elevation deficit (difference between rate of submergence and vertical land development) prior to hurricanes was less in burned plots (6.2 millimeters per year [mm yr-1]) compared to nonburned plots (7.2 mm yr-1). 8. Storm sediments delivered by Hurricane Ike raised elevations an average of 7.4 centimeters (cm), which countered an elevation deficit that had accrued over 11 years. Our findings provide preliminary insights into elevation dynamics occurring in brackish marshes of the Texas Chenier Plain under prescribed fire management. The results of this study indicate that prescribed burning conducted at 3- to 5-year intervals is not likely to negatively impact the long-term sustainability of S. patens-dominated brackish marshes at McFaddin National Wildlife Refuge and may offset existing elevation deficits by ? 1 mm yr-1. The primary drivers of elevation change varied in time and space, leading to a more complex situation in terms of predicting how disturbances may alter elevation trajectories. The potential effect of burning on elevation change in other marshes will depend on several site-specific factors, including geomorphic/ sedimentary setting, tide range, local rate of relative sea level rise, plant species composition, additional management practices (for example, for flood control), and disturbance types and frequency (for example, hurricanes or herbivore grazing). Increasing the scope of inference would require installation of SETs in replicate marshes undergoing different prescribed fire intervals

McKee, Karen L.; Grace, James B.

2012-01-01

234

Combining earthquake forecasts using differential probability gains  

NASA Astrophysics Data System (ADS)

We describe an iterative method to combine seismicity forecasts. With this method, we produce the next generation of a starting forecast by incorporating predictive skill from one or more input forecasts. For a single iteration, we use the differential probability gain of an input forecast relative to the starting forecast. At each point in space and time, the rate in the next-generation forecast is the product of the starting rate and the local differential probability gain. The main advantage of this method is that it can produce high forecast rates using all types of numerical forecast models, even those that are not rate-based. Naturally, a limitation of this method is that the input forecast must have some information not already contained in the starting forecast. We illustrate this method using the Every Earthquake a Precursor According to Scale (EEPAS) and Early Aftershocks Statistics (EAST) models, which are currently being evaluated at the US testing center of the Collaboratory for the Study of Earthquake Predictability. During a testing period from July 2009 to December 2011 (with 19 target earthquakes), the combined model we produce has better predictive performance - in terms of Molchan diagrams and likelihood - than the starting model (EEPAS) and the input model (EAST). Many of the target earthquakes occur in regions where the combined model has high forecast rates. Most importantly, the rates in these regions are substantially higher than if we had simply averaged the models.

Shebalin, Peter N.; Narteau, Clément; Zechar, Jeremy Douglas; Holschneider, Matthias

2014-12-01

235

Gain without inversion for gamma radiation  

NASA Astrophysics Data System (ADS)

Gain without inversion for a level-mixing scheme is studied for gamma-optics. In this scheme nuclear level mixing is created by misalignment of a dc magnetic field with respect to the c-axis of a noncubic crystal. Axially symmetric electron nuclear coupling and nuclear quadrupole interaction with an electric field gradient produce two electro-nuclear levels that are equally mixed and split, with the energy gap dependent on the tilting angle of the magnetic field. By laser excitation of an electron transition, nuclear spin coherence can be created between these two levels. A condition is found for the predominant population of the dark state by spontaneous emission. This state is a particular superposition of the mixed states, such that, by selection rules, the transition from it cannot be excited by ?-radiation. If all absorbing nuclei are in the dark state, resonant ?-absorption is suppressed in the sample. At the same condition, ?-emission of the excited nuclei is allowed because the corresponding transition terminates in another component of the mixed states superposition. The constraints on the tilting angle and reciprocal gap between two mixed electro-nuclear levels are found, setting the limits to these values beyond which the gain without inversion becomes impossible.

Shakhmuratov, R. N.; Kozyreff, G.; Coussement, R.; Odeurs, J.; Mandel, P.

2000-05-01

236

Risk Insights Gained from Fire Incidents  

SciTech Connect

There now exist close to 20 years of history in the application of Probabilistic Risk Assessment (PRA) for the analysis of fire risk at nuclear power plants. The current methods are based on various assumptions regarding fire phenomena, the impact of fire on equipment and operator response, and the overall progression of a fire event from initiation through final resolution. Over this same time period, a number of significant fire incidents have occurred at nuclear power plants around the world. Insights gained from US experience have been used in US studies as the statistical basis for establishing fire initiation frequencies both as a function of the plant area and the initiating fire source.To a lesser extent, the fire experience has also been used to assess the general severity and duration of fires. However, aside from these statistical analyses, the incidents have rarely been scrutinized in detail to verify the underlying assumptions of fire PRAs. This paper discusses an effort, under which a set of fire incidents are being reviewed in order to gain insights directly relevant to the methods, data, and assumptions that form the basis for current fire PRAs. The paper focuses on the objectives of the effort, the specific fire events being reviews methodology, and anticipated follow-on activities.

Kazarians, Mardy; Nowlen, Steven P.

1999-06-10

237

Giant Raman gain in silicon nanocrystals  

PubMed Central

Nanostructured silicon has generated a lot of interest in the past decades as a key material for silicon-based photonics. The low absorption coefficient makes silicon nanocrystals attractive as an active medium in waveguide structures, and their third-order nonlinear optical properties are crucial for the development of next generation nonlinear photonic devices. Here we report the first observation of stimulated Raman scattering in silicon nanocrystals embedded in a silica matrix under non-resonant excitation at infrared wavelengths (~1.5??m). Raman gain is directly measured as a function of the silicon content. A giant Raman gain from the silicon nanocrystals is obtained that is up to four orders of magnitude greater than in crystalline silicon. These results demonstrate the first Raman amplifier based on silicon nanocrystals in a silica matrix, thus opening new perspectives for the realization of more efficient Raman lasers with ultra-small sizes, which would increase the synergy between electronic and photonic devices. PMID:23187620

Sirleto, Luigi; Antonietta Ferrara, Maria; Nikitin, Timur; Novikov, Sergei; Khriachtchev, Leonid

2012-01-01

238

Variable Gain Semiconductor Optical Linear Amplifier (OLA)  

NASA Astrophysics Data System (ADS)

The semiconductor optical amplifier (SOA) is a versatile component that can be deployed to meet the expanding applications associated with the introduction of additional functionalities at the optical level in wavelength division multiplexed systems. The future network requires low cost, small footprint, directly controllable amplification throughout the different application layers from long haul through to metro; the intrinsic size and integration capability advantages will ensure that the SOA plays a key role in this evolution. In multi-wavelength gating/amplification applications the gain dynamics, oscillating at timescales comparable to that of the data which is being amplified, introduce issues of pattern dependent waveform distortion (patterning) in single channel, and inter-channel cross-talk in multi-wavelength cases which require management through careful SOA design and understanding of the network application scenarios. In this paper, an optical linear amplifier (OLA) architecture with the unique capability to provide variable gain whilst maintaining linear operation at high output saturation powers will be described. Initial characterisation results for the OLA will be presented.

Michie, W. Craig; Kelly, Tony; Tomlinson, Andy; Andonovic, Ivan

2002-12-01

239

Economic Gains from Trade Liberalization: NAFTA's Impact  

NSDL National Science Digital Library

The October 1997 Chicago Fed Letter issue, "Economic Gains from Trade Liberalization - NAFTA's impact" by Michael A. Kouparitsas, (available in Adobe Acrobat [.pdf] format only) evaluates the gains from NAFTA. Recently, the debate over free trade has intensified in light of the failure of President Clinton to obtain fast-track authority from Congress. On September 17, 1997, President Clinton went against the liberals in his own party to request fast-track authority from Congress to negotiate new trade accords. The Senate approved the President's request for fast track on November 5, 1997 but the vote in the House was shelved when it appeared likely that fast-track would be defeated. The opponents of free-trade consist mainly of trade unions who are worried about the loss of jobs to countries with cheap labor, and environmentalists concerned about the effect of free trade on environmental standards. The supporters of free-trade are mainly businesses who see business potential in the larger market that would be created by expanding free trade.

Kouparitsas, Michael A.

1997-01-01

240

Amplified Warming Rates in High Elevation Regions  

NASA Astrophysics Data System (ADS)

We use ground-based and satellite-retrieved observations in conjunction with output from global climate model simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to determine whether warming rates in high elevation regions are significantly different than in their lower elevation surroundings. In addition, for regions where there is enhanced warming at higher elevations, we investigate several of the potential mechanisms that may contribute to this enhancement. For the mid-latitudes in the Northern Hemisphere, the multi-model ensemble indicates that warming rates during the 21st century will be enhanced at high elevations relative to their lower elevation counterparts at the same latitude. This effect is most pronounced for daily minimum temperatures during the cold season in the Tibetan Plateau/Himalayan region. A neural network analysis is used to identify and quantify some of the potential mechanisms responsible for enhanced warming rates, including the effects of variables such as atmospheric water vapor, clouds, snow cover, and aerosols on the radiation and surface heat budgets. We also demonstrate that satellite retrievals can be used to expand the often sparse ground-based observations in such regions and that they provide the correct relationships between variables. Please fill in your abstract text.

Miller, James; Naud, Catherine; Chen, Yonghua; Ghatak, Debjani; Rangwala, Imtiaz; Sinsky, Eric

2014-05-01

241

site plan, floor plan, southeast and east elevations, detail showing ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

site plan, floor plan, southeast and east elevations, detail showing original front entrance, interior detail showing fireplace in elevation - Neiman House, 1930 Providence Road, Charlotte, Mecklenburg County, NC

242

Hurricane Wilma's impact on overall soil elevation and zones within the soil profile in a mangrove forest  

USGS Publications Warehouse

Soil elevation affects tidal inundation period, inundation frequency, and overall hydroperiod, all of which are important ecological factors affecting species recruitment, composition, and survival in wetlands. Hurricanes can dramatically affect a site's soil elevation. We assessed the impact of Hurricane Wilma (2005) on soil elevation at a mangrove forest location along the Shark River in Everglades National Park, Florida, USA. Using multiple depth surface elevation tables (SETs) and marker horizons we measured soil accretion, erosion, and soil elevation. We partitioned the effect of Hurricane Wilma's storm deposit into four constituent soil zones: surface (accretion) zone, shallow zone (0–0.35 m), middle zone (0.35–4 m), and deep zone (4–6 m). We report expansion and contraction of each soil zone. Hurricane Wilma deposited 37.0 (± 3.0 SE) mm of material; however, the absolute soil elevation change was + 42.8 mm due to expansion in the shallow soil zone. One year post-hurricane, the soil profile had lost 10.0 mm in soil elevation, with 8.5 mm of the loss due to erosion. The remaining soil elevation loss was due to compaction from shallow subsidence. We found prolific growth of new fine rootlets (209 ± 34 SE g m?2) in the storm deposited material suggesting that deposits may become more stable in the near future (i.e., erosion rate will decrease). Surficial erosion and belowground processes both played an important role in determining the overall soil elevation. Expansion and contraction in the shallow soil zone may be due to hydrology, and in the middle and bottom soil zones due to shallow subsidence. Findings thus far indicate that soil elevation has made substantial gains compared to site specific relative sea-level rise, but data trends suggest that belowground processes, which differ by soil zone, may come to dominate the long term ecological impact of storm deposit.

Whelan, K.R.T.; Smith, T. J., III; Anderson, G.H.; Ouellette, M.L.

2009-01-01

243

Advanced composite elevator for Boeing 727 aircraft  

NASA Technical Reports Server (NTRS)

Detail design activities are reported for a program to develop an advanced composites elevator for the Boeing 727 commercial transport. Design activities include discussion of the full scale ground test and flight test activities, the ancillary test programs, sustaining efforts, weight status, and the production status. Prior to flight testing of the advanced composites elevator, ground, flight flutter, and stability and control test plans were reviewed and approved by the FAA. Both the ground test and the flight test were conducted according to the approved plan, and were witnessed by the FAA. Three and one half shipsets have now been fabricated without any significant difficulty being encountered. Two elevator system shipsets were weighed, and results validated the 26% predicted weight reduction. The program is on schedule.

1979-01-01

244

Vertical vibration analysis for elevator compensating sheave  

NASA Astrophysics Data System (ADS)

Most elevators applied to tall buildings include compensating ropes to satisfy the balanced rope tension between the car and the counter weight. The compensating ropes receive tension by the compensating sheave, which is installed at the bottom space of the elevator shaft. The compensating sheave is only suspended by the compensating ropes, therefore, the sheave can move vertically while the car is traveling. This paper shows the elevator dynamic model to evaluate the vertical motion of the compensating sheave. Especially, behavior in emergency cases, such as brake activation and buffer strike, was investigated to evaluate the maximum upward motion of the sheave. The simulation results were validated by experiments and the most influenced factor for the sheave vertical motion was clarified.

Watanabe, Seiji; Okawa, Takeya; Nakazawa, Daisuke; Fukui, Daiki

2013-07-01

245

Application of spring tabs to elevator controls  

NASA Technical Reports Server (NTRS)

Equations are presented for calculating the stick-force characteristics obtained with a spring-tab type of elevator control. The main problems encountered in the design of a satisfactory elevator spring tab are to provide stick forces in the desired range, to maintain the force per g sufficiently constant throughout the speed range, to avoid undesirable "feel" of the control in ground handling or in flight at low airspeeds, and to prevent flutter. Examples are presented to show the design features of spring tabs required to solve these problems for airplanes of various sizes.

Phillips, William H

1944-01-01

246

Elevated atmospheric carbon dioxide increases soil carbon  

SciTech Connect

In a study funded by the U.S. Department of Energy's Office of Science, researchers from Argonne and Oak Ridge National Laboratories and Kansas State and Texas A&M Universities evaluated the collective results of earlier studies by using a statistical procedure called meta-analysis. They found that on average elevated CO2 increased soil carbon by 5.6 percent over a two to nine year period. They also measured comparable increases in soil carbon for Tennessee deciduous forest and Kansas grassland after five to eight years of experimental exposure to elevated CO2.

Norby, Richard J [ORNL; Jastrow, Julie D [ORNL; Miller, Michael R [ORNL; Matamala, Roser [Argonne National Laboratory (ANL); Boutton, Thomas W [Texas A& M University; Rice, Charles W [ORNL; Owensby, Clenton E [Kansas State University

2005-01-01

247

Forest succession at elevated CO2  

SciTech Connect

We tested hypotheses concerning the response of forest succession to elevated CO2 in the FACTS-1 site at the Duke Forest. We quantified growth and survival of naturally recruited seedlings, tree saplings, vines, and shrubs under ambient and elevated CO2. We planted seeds and seedlings to augment sample sites. We augmented CO2 treatments with estimates of shade tolerance and nutrient limitation while controlling for soil and light effects to place CO2 treatments within the context of natural variability at the site. Results are now being analyzed and used to parameterize forest models of CO2 response.

Clark, James S.; Schlesinger, William H.

2002-02-01

248

20 CFR 220.141 - Substantial gainful activity, defined.  

Code of Federal Regulations, 2013 CFR

20 Employees' Benefits 1 2013-04-01... Substantial gainful activity, defined. 220...141 Employees' Benefits RAILROAD RETIREMENT... Substantial Gainful Activity § 220.141 Substantial...involves doing significant physical or mental...

2013-04-01

249

20 CFR 220.141 - Substantial gainful activity, defined.  

Code of Federal Regulations, 2014 CFR

20 Employees' Benefits 1 2014-04-01... Substantial gainful activity, defined. 220...141 Employees' Benefits RAILROAD RETIREMENT... Substantial Gainful Activity § 220.141 Substantial...involves doing significant physical or mental...

2014-04-01

250

Preventing and Managing Medication-Related Weight Gain  

MedlinePLUS

... these medications may lead to weight gain. The antipsychotic medications, in particular, have also been associated with ... medications that can lead to weight gain include: Antipsychotics: such as aripiprazole ( Abilify ), chlorpromazine ( Thorazine ), clozapine ( Clozaril ), ...

251

Gain measurements of scattering-assisted terahertz quantum cascade lasers  

E-print Network

Using terahertz time-domain spectroscopy, the gain of scattering-assisted terahertz quantum cascade lasers is measured. By examining the intersubband gain and absorption over a wide range of bias voltages, we experimentally ...

Hu, Qing

252

Comparisons of selection indices achieving predetermined proportional gains  

E-print Network

Comparisons of selection indices achieving predetermined proportional gains Y. ITOH Y. YAMADA different selection indices to achieve predetermined proportional gains in some traits. One with proportional constraints proposed by HARVILLE (1975) and TALUS (1985). They are described in uniform notations

Paris-Sud XI, Université de

253

Effects of internal gain assumptions in building energy calculations  

SciTech Connect

The utilization of direct solar gains in buildings can be affected by operating profiles, such as schedules for internal gains, thermostat controls, and ventilation rates. Building energy analysis methods use various assumptions about these profiles. The effects of typical internal gain assumptions in energy calculations are described. Heating and cooling loads from simulations using the DOE 2.1 computer code are compared for various internal-gain inputs: typical hourly profiles, constant average profiles, and zero gain profiles. Prototype single-family-detached and multi-family-attached residential units are studied with various levels of insulation and infiltration. Small detached commercial buildings and attached zones in large commercial buildings are studied with various levels of internal gains. The results of this study indicate that calculations of annual heating and cooling loads are sensitive to internal gains, but in most cases are relatively insensitive to hourly variations in internal gains.

Christensen, C.; Perkins, R.

1981-01-01

254

Gaining Public Support for RFI Mitigation  

NASA Astrophysics Data System (ADS)

Astronomy's access to radio spectrum depends to a great extent on international and national regulatory agencies. Such regulation is inherently a political process, so support for radio astronomy by the general public is vital to success. Educating the public about a subject perceived as so highly technical can be challenging. Success in advancing public understanding of the issue and gaining public support is based on two foundations: publicizing the societal value of astronomy; and explaining the interference problem in non-technical terms that draw upon the well-understood terminology of environmental protection. Effective communication can convince non-scientists that astronomical research is a vital and beneficial activity, and that unpolluted access to the radio spectrum is essential to making the new discoveries that are astronomy's contribution to humanity. Convinced of this, the public will support imposing the expense of engineering measures designed to protect radio astronomy, just as they support spending money to protect air, water and soil from pollution.

Finley, D. G.

2004-05-01

255

TEPC gas gain measurements in propane.  

PubMed

Knowledge of the gas gain is important to optimise the design and the operating characteristics of tissue-equivalent proportional counters (TEPCs), especially for simulated sites smaller than 1 µm. TEPC area monitors of the order of centimetres must operate at very low gas pressure to simulate micrometric volumes, consequently the Townsend theory cannot be applied: effects related to the presence of an electric-field gradient become important and must be considered. A detailed description of the electron avalanche formation is complex, but in most practical cases an analytical formula can be used. The so-called gradient-field model includes three characteristic constants of the counting gas, which were already experimentally determined for propane-tissue equivalent (TE) and dimethyl ether (DME) gases. The aim of this work is to measure the gas-dependent parameters for propane gas. Preliminary results obtained with a spherical TEPC are presented. PMID:24493783

Moro, D; Chiriotti, S; Colautti, P; Conte, V

2014-10-01

256

High Gain Fast Ignition Point Design  

NASA Astrophysics Data System (ADS)

The fast ignition (FI) approach to inertial confinement fusion offers the potential for achieving the high target gains required for Inertial Fusion Energy (IFE). In FI a D-T fuel capsule is first compressed via a quasi-isochoric implosion to form a high density core, and then ignited with a short-pulse laser-generated relativistic electron beam. This paper reports progress on the development of a point design for an indirect-drive re-entrant cone FI target. The design incorporates 2-D radiation-hydrodynamics modeling of the capsule implosion around a cone, particle-in-cell (PIC) modeling of the short-pulse laser absorption and electron generation at the cone tip, and hybrid-PIC modeling of the electron transport and heating in the compressed fuel. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Patel, P. K.; Amendt, P.; Chen, C. D.; Clark, D.; Cohen, B.; Hey, D. S.; Divol, L.; Higginson, D.; Ho, D.; Homoelle, D.; Kemp, A. J.; Key, M. H.; Larson, D.; Lasinski, B.; Le Pape, S.; Ma, T.; McLean, H.; Meeker, D. J.; Ping, Y.; Shay, H.; Strozzi, D. J.; Tabak, M.; Town, R. P. J.; Westover, B.; Wilks, S. C.

2010-11-01

257

Evaluation of Experimental Data from the Gains Balloon GPS Surface Reflection Instrument  

NASA Technical Reports Server (NTRS)

The GPS Surface Reflection Instrument was integrated as an experiment on the GAINS (Global Airocean IN-situ System) 48-hour balloon mission flown in June 2002. The data collected by similar instruments in the past has been used to measure sea state from which ocean surface winds can be accurately estimated. The GPS signal has also been shown to be reflected from wetland areas and even from subsurface moisture. The current version of the instrument has been redesigned to be more compact, use less power, and withstand a greater variation in environmental conditions than previous versions. This instrument has also incorporated a new data collection mode to track 5 direct satellites (providing a continuous navigation solution) and multiplex the remaining 7 channels to track the reflected signal of the satellite tracked in channel 0. The new software mode has been shown to increase the signal to noise ratio of the collected data and enhance the science return of the instrument. During the GAINS balloon flight over the Northwest US, the instrument measured surface reflections as they were detected over the balloon's ground track. Since ground surface elevations in this area vary widely from the WGS-84 ellipsoid altitude, the instrument software has been modified to incorporate a surface altitude correction based on USGS 30-minute Digital Elevation Models. Information presented will include facts about instrument design goals, data collection methodologies and algorithms, and will focus on results of the science data analyses for the mission.

Ganoe, George G.; Johnson, Thomas A.; Somero, John Ryan

2002-01-01

258

Management of Antipsychotic-Related Weight Gain  

PubMed Central

Despite variations across individuals and agents, antipsychotics are associated with clearly documented weight gain and adverse metabolic effects. Although increased appetite/caloric intake and various receptors, hormones and peptides have been implicated, biological mechanisms contributing to the increase in weight and glucose and lipid abnormalities with antipsychotics are largely unknown. This has hampered the creation of antipsychotics that are free of cardiometabolic effects, even in antipsychotic-naïve/early-phase patients, as well as the development of strategies that can prevent or drastically diminish the adverse cardiometabolic effects. In general, three strategies can reduce the cardiometabolic risk of antipsychotics: 1) switching to a less orexigenenic/metabolically adverse antipsychotic, 2) adjunctive behavioral treatments and 3) adjunctive pharmacologic interventions. However each of these strategies has only been modestly effective. Among different behavioral interventions (N=14, n=746), group and individual treatment, dietary counseling and cognitive-behavioral therapy seem to be similarly effective. Among 15 different pharmacologic strategies (N=35 , n=1,629), only metformin, fenfluramine, sibutramine, topiramate and reboxetine were more effective than placebo, with the most evidence being available for metformin, yet without any head-to-head trials comparing individual pharmacologic interventions. Even in the most successful trials, however, the risk reduction was modest. Weight was not decreased to a pre-treatment level, and despite superiority compared to placebo, weight gain still often occurred, particularly in antipsychotic-naïve patients and when interventions were “preventively” co-initiated with antipsychotics. Future research should focus on combining treatment modalities or agents and on exploring novel mechanism-based interventions. PMID:20586697

Maayan, Lawrence; Correll, Christoph U.

2012-01-01

259

A simple model of gain saturation in high gain single pass free electron lasers  

Microsoft Academic Search

The saturation dynamics of a high gain single passage FEL is reproduced by means of an analytical model based on Bloch-type equations, similar to those governing the physics of conventional lasers. The main results of the paper is the proof that the evolution from small to strong signal regime can be described in terms of the logistic function, whose validity

G. Dattoli; L. Giannessi; P. L Ottaviani; M. Carpanese

1997-01-01

260

Focusing on Short-Term Achievement Gains Fails to Produce Long-Term Gains  

ERIC Educational Resources Information Center

The short-term emphasis engendered by No Child Left Behind (NCLB) has focused research predominantly on unraveling the complexities and uncertainties in assessing short-term results, rather than developing methods and assessing results over the longer term. In this paper we focus on estimating long-term gains and address questions important to…

Grissmer, David W.; Ober, David R.; Beekman, John A.

2014-01-01

261

Gains in bank mergers: Evidence from the bond markets  

Microsoft Academic Search

We present evidence that the adjusted returns of merging banks’ bonds are positive and significant across pre-merger and announcement months. The cross-sectional evidence indicates that the primary determinants of merger-related bondholder gains are diversification gains, gains associated with achieving too-big-to-fail status, and, to a lesser degree, synergy gains. We obtain the same finding when we examine the acquiring banks’ credit

Mar??a Fabiana Penas; Haluk Unal

2004-01-01

262

Gain compression in GaN HEMT amplifiers  

Microsoft Academic Search

Volterra series analysis is used to determine linear and nonlinear gain, output power of a GaN HEMT amplifier. Gain compression defined as the difference between linear and nonlinear gain is reported for varying temperatures. Measured 1-dB gain compression of 17.5 dBm for a 1×500 ?m Al0.15Ga0.85N\\/GaN HEMT at 300 K and at 2 GHz is in excellent agreement with the

Arif Ahmed; Syed S. Islam; A. F. M. Anwar

2001-01-01

263

Modeling of gain in erbium-doped fiber amplifiers  

Microsoft Academic Search

An analytic method is described for fully characterizing the gain of an erbium-doped fiber amplifier (EDFA) that is based on easily measured monochromatic absorption data. The analytic expressions presented, which involve the solution of one transcendental equation, can predict signal gains and pump absorptions in an amplifier containing an arbitrary number of pumps and signals from arbitrary directions. The gain

A. A. M. Saleh; R. M. Jopson; J. D. Evankow; J. Aspell

1990-01-01

264

24 CFR 3280.507 - Comfort heat gain.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Comfort heat gain. 3280.507 Section 3280.507...Thermal Protection § 3280.507 Comfort heat gain. Information necessary to calculate...specified in this part. (a) Transmission heat gains. Homes complying with this...

2013-04-01

265

24 CFR 3280.507 - Comfort heat gain.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Comfort heat gain. 3280.507 Section 3280.507...Thermal Protection § 3280.507 Comfort heat gain. Information necessary to calculate...specified in this part. (a) Transmission heat gains. Homes complying with this...

2011-04-01

266

24 CFR 3280.507 - Comfort heat gain.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Comfort heat gain. 3280.507 Section 3280.507...Thermal Protection § 3280.507 Comfort heat gain. Information necessary to calculate...specified in this part. (a) Transmission heat gains. Homes complying with this...

2010-04-01

267

24 CFR 3280.507 - Comfort heat gain.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Comfort heat gain. 3280.507 Section 3280.507...Thermal Protection § 3280.507 Comfort heat gain. Information necessary to calculate...specified in this part. (a) Transmission heat gains. Homes complying with this...

2014-04-01

268

24 CFR 3280.507 - Comfort heat gain.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Comfort heat gain. 3280.507 Section 3280.507...Thermal Protection § 3280.507 Comfort heat gain. Information necessary to calculate...specified in this part. (a) Transmission heat gains. Homes complying with this...

2012-04-01

269

Gain characterization and passive modelocking of electrically pumped VECSELs  

E-print Network

Gain characterization and passive modelocking of electrically pumped VECSELs W.P. Pallmann,1,* C surface emitting lasers (EP-VECSELs) is presented with spectrally resolved measurements of the gain and with gain saturation measurements of two EP-VECSEL samples with different field enhancement in the quantum

Keller, Ursula

270

Measurements and modeling of gain coefficients for neodymium laser glasses  

Microsoft Academic Search

Small-signal gain coefficients are reported for neodymium in silicate, phosphate, fluorophosphate, and fluoroberyllate laser glasses. Measurements were made in a disk amplifier under identical conditions. Using spectroscopic data as the input, amplifier gain is calculated as a function of flashlamp energy, pumping pulse duration, disk thickness, and Nd-doping. The agreement between predicted and measured gains is generally with ±10 percent,

GARY J. LINFORD; R. ALLYN SAROYAN; JOHN B. TRENHOLME; MARVIN J. WEBER

1979-01-01

271

Gain Modulation: Applications and Mechanisms L. F. Abbott  

E-print Network

Gain Modulation: Applications and Mechanisms L. F. Abbott Volen Center for Complex Systems Brandeis. Population Coding (Elsevier, Amsterdam). Introduction Gain modulation, which is seen in many cortical areas, is a ubiquitous form of neuronal representation, gain modulation appears to be a widespread mechanism of neuronal

Chance, Frances S.

272

Climatic change at high elevation sites  

SciTech Connect

A Workshop on climatic change at high elevation sites was held September 11-15, 1995 in Wengen, Switzerland. The meeting was sponsored by both U.S. (Department of Energy, National Science Foundation and National Oceanic & Atmospheric Administration) and European (Swiss National Science Foundation, European Science Foundation, Swiss Federal Institute of Technology) agencies. The goals of the workshop were to (1) focus the attention of the world climate community on the existence of unique high elevation geophysical records around the world, (2) highlight the value of these observing sites for climate change detection efforts and to help insure the continued support of governments and of relevant institutions in the maintenance of these high elevation data gathering efforts, (3) discuss and evaluate climatic trends that may be present in these records, and to compare the information with available paleoenvironmental records of glaciers, tree-rings and varved sediments from the alpine zones, and (4) discuss and evaluate information about elevational differences in current and projected greenhouse-gas induced climatic changes in coupled General Circulation Models.

Dr. Henry F. Diaz

1998-07-23

273

75 FR 75941 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Internal Agency Docket No. FEMA-B-1164] Proposed Flood Elevation...identified by Docket No. FEMA-B-1164, to Luis Rodriguez...confluence with None +12 City of Fort Pierce, Fivemile Creek. Unincorporated...None +16 City of Fort Pierce, Unincorporated Areas of...

2010-12-07

274

TERRASTREAM: From Elevation Data to Watershed Hierarchies  

E-print Network

TERRASTREAM: From Elevation Data to Watershed Hierarchies Andrew Danner Swarthmore College, and construction of a watershed hierarchy. Our approach has several advantages over existing methods. First, we-scalable stage would create a bottleneck and limit overall scalability. Second, we develop the algorithms

Yi, Ke "Kevin"

275

Elevated temperature biaxial fatigue. Final Report  

Microsoft Academic Search

A 3 year experimental program for studying elevated temperature biaxial fatigue of a nickel based alloy Hastelloy-X has been completed. A new high temperature fatigue test facility with unique capabilities has been developed. Effort was directed toward understanding multiaxial fatigue and correlating the experimental data to the existing theories of fatigue failure. The difficult task of predicting fatigue lives for

1985-01-01

276

76 FR 43968 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-07-22

277

75 FR 31368 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-06-03

278

76 FR 39063 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-07-05

279

75 FR 61371 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-10-05

280

76 FR 72661 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-11-25

281

76 FR 40670 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-07-11

282

75 FR 61373 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-10-05

283

75 FR 9561 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-03-03

284

76 FR 58436 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-09-21

285

76 FR 21695 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-04-18

286

76 FR 53082 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-08-25

287

75 FR 77598 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-12-13

288

75 FR 19328 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-04-14

289

75 FR 55527 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-09-13

290

76 FR 5769 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-02-02

291

75 FR 29253 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-05-25

292

75 FR 78650 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-12-16

293

76 FR 19005 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-04-06

294

76 FR 8978 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2011-02-16

295

75 FR 59181 - Proposed Flood Elevation Determinations  

Federal Register 2010, 2011, 2012, 2013, 2014

...Comments are requested on the proposed Base (1% annual-chance) Flood Elevations...Reorganization Plan No. 3 of 1978, 3 CFR, 1978 Comp., p. 329; E.O. 12127, 44 FR 19367, 3 CFR, 1979 Comp., p. 376. Sec. 67.4 [Amended]...

2010-09-27

296

Advanced composite elevator for Boeing 727 aircraft  

NASA Technical Reports Server (NTRS)

Detail design activities are reported for a program to develop an advanced composites elevator for the Boeing 727 commercial transport. Design activities include discussion and results of the ancillary test programs, sustaining efforts, weight status, manufacturing producibility studies, quality assurance development, and production status.

1978-01-01

297

ICESat: Ice, Cloud, and land Elevation Satellite  

NSDL National Science Digital Library

This brochure describes NASA's ICESat mission ((Ice, Cloud, and land Elevation Satellite), which was launched January 12, 2003. ICESat is the benchmark Earth Observing System mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics.

2007-11-01

298

Elevated fetal steroidogenic activity in autism.  

PubMed

Autism affects males more than females, giving rise to the idea that the influence of steroid hormones on early fetal brain development may be one important early biological risk factor. Utilizing the Danish Historic Birth Cohort and Danish Psychiatric Central Register, we identified all amniotic fluid samples of males born between 1993 and 1999 who later received ICD-10 (International Classification of Diseases, 10th Revision) diagnoses of autism, Asperger syndrome or PDD-NOS (pervasive developmental disorder not otherwise specified) (n=128) compared with matched typically developing controls. Concentration levels of ?4 sex steroids (progesterone, 17?-hydroxy-progesterone, androstenedione and testosterone) and cortisol were measured with liquid chromatography tandem mass spectrometry. All hormones were positively associated with each other and principal component analysis confirmed that one generalized latent steroidogenic factor was driving much of the variation in the data. The autism group showed elevations across all hormones on this latent generalized steroidogenic factor (Cohen's d=0.37, P=0.0009) and this elevation was uniform across ICD-10 diagnostic label. These results provide the first direct evidence of elevated fetal steroidogenic activity in autism. Such elevations may be important as epigenetic fetal programming mechanisms and may interact with other important pathophysiological factors in autism.Molecular Psychiatry advance online publication, 3 June 2014; doi:10.1038/mp.2014.48. PMID:24888361

Baron-Cohen, S; Auyeung, B; Nørgaard-Pedersen, B; Hougaard, D M; Abdallah, M W; Melgaard, L; Cohen, A S; Chakrabarti, B; Ruta, L; Lombardo, M V

2014-06-01

299

Automatic elevator system for maintenance services  

Microsoft Academic Search

This work presents an electrically assisted automatic elevator system for maintenance of street lights. The system was installed in a public illumination maintenance truck. It consists of a telescopic column, a base structure, and a platform. The whole operation is monitored and controlled by a PLC. The system aims at reducing efforts in maintenance tasks as well as improving the

R. A. Roncolatto; N. W. Romanelli; O. Horikawa; A. Hirakawa; S. M. Amancio; M. Silverio

2006-01-01

300

Low Elevated Lead Levels and Mental Retardation.  

ERIC Educational Resources Information Center

The relationship between low elevated lead absorption and mild mental retardation was investigated in 40 rural children (preschool to grade 12) without demonstrable cause for their retardation. Trace mineral analysis of hair samples from Ss and a control group (N=20) indicated the mean hair lead concentrations for the retarded Ss were considerably…

Marlowe, Mike; And Others

301

Elevation correction and the geoid tutorial  

NSDL National Science Digital Library

The Earth is not a perfect sphere, but is instead more like a slightly squashed sphere called an ellipsoid. Because of this, GPS receivers must use a correction model (called a geoid) to calculate true elevation above sea level. UNAVCO has prepared this explanation for both teachers and students to learn more about accuracy, scientific models, and how GPS receivers work.

Unavco

302

Cokriging model for estimation of water table elevation  

Microsoft Academic Search

In geological settings where the water table is a subdued replica of the ground surface, cokriging can be used to estimate the water table elevation at unsampled locations on the basis of values of water table elevation and ground surface elevation measured at wells and at points along flowing streams. The ground surface elevation at the estimation point must also

R. J. Hoeksema; R. B. Clapp; A. L. Thomas; A. E. Hunley; N. D. Farrow; K. C. Dearstone

1989-01-01

303

Elevator Group Supervisory Control of Double-Deck and  

E-print Network

1 Elevator Group Supervisory Control of Double-Deck and Multi-Car Elevator Systems using Genetic Control Systems EGSCS 1970 Artificial Intelligence AI) Double-Deck Elevator Systems DDES Multi Network Programming YU, Lu 7 #12;2 Genetic Algorithm GA Genetic Programming GP Elevator Group Supervisory

Fernandez, Thomas

304

Elevator Group Supervisory Control of Double-Deck and  

E-print Network

Elevator Group Supervisory Control of Double-Deck and Multi-Car Elevator Systems using and real world problems. GNP was firstly applied to Elevator Group Supervisory Control Syste m (EGSCS such as tile-worlds models. EGSCS is the system, where the elevator group supervisory controller controls

Fernandez, Thomas

305

The design of the elevator control based on PLC  

NASA Astrophysics Data System (ADS)

Elevator is the vertical vehicle of modern high building,which has close relationship with the life of people.The elevator developed very quickly with the increasing demand of people.The drag of elevator developed to use the frequency conversion and voltage transformation to realize the speed regulation.The logic control of elevator is accomplished by PLC instead of relay control.The article uses the PLC to control the elevator based on existed current frequency transformer.Through the resonable choice and design,we can increase the control level of the elevator,and improve the safety and comfortable feeling of elevator,and obtain perfect contrl effect.

Zheng, Yanling; Ning, Xin; Wang, Zhankui

2011-10-01

306

Caribbean mangroves adjust to rising sea level through biotic controls on change in soil elevation  

USGS Publications Warehouse

Aim The long-term stability of coastal ecosystems such as mangroves and salt marshes depends upon the maintenance of soil elevations within the intertidal habitat as sea level changes. We examined the rates and processes of peat formation by mangroves of the Caribbean Region to better understand biological controls on habitat stability. Location Mangrove-dominated islands on the Caribbean coasts of Belize, Honduras and Panama were selected as study sites. Methods Biological processes controlling mangrove peat formation were manipulated (in Belize) by the addition of nutrients (nitrogen or phosphorus) to Rhizophora mangle (red mangrove), and the effects on the dynamics of soil elevation were determined over a 3-year period using rod surface elevation tables (RSET) and marker horizons. Peat composition and geological accretion rates were determined at all sites using radiocarbon-dated cores. Results The addition of nutrients to mangroves caused significant changes in rates of mangrove root accumulation, which influenced both the rate and direction of change in elevation. Areas with low root input lost elevation and those with high rates gained elevation. These findings were consistent with peat analyses at multiple Caribbean sites showing that deposits (up to 10 m in depth) were composed primarily of mangrove root matter. Comparison of radiocarbon-dated cores at the study sites with a sea-level curve for the western Atlantic indicated a tight coupling between peat building in Caribbean mangroves and sea-level rise over the Holocene. Main conclusions Mangroves common to the Caribbean region have adjusted to changing sea level mainly through subsurface accumulation of refractory mangrove roots. Without root and other organic inputs, submergence of these tidal forests is inevitable due to peat decomposition, physical compaction and eustatic sea-level rise. These findings have relevance for predicting the effects of sea-level rise and biophysical processes on tropical mangrove ecosystems.

McKee, K.L.; Cahoon, D.R.; Feller, I.C.

2007-01-01

307

35. To left of center is freight elevator used to ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. To left of center is freight elevator used to move materials to the upper floors of the building. This elevator is also powered via the belts and drive shafts which operate the machine tools. Sign on elevator reads 'For Mr. Edison's Personal Use Only;' according to rumor, Edison was encouraged to use the elevator as he grew older, but refused. The elevator is designed for freight only. - Thomas A. Edison Laboratories, Building No. 5, West Orange, Essex County, NJ

308

Mechanism of the metallic metamaterials coupled to the gain material.  

PubMed

We present evidence of strong coupling between the gain material and the metallic metamaterials. It is of vital importance to understand the mechanism of the coupling of metamaterials with the gain medium. Using a four-level gain system, the numerical pump-probe experiments are performed in several configurations (split-ring resonators (SRRs), inverse SRRs and fishnets) of metamaterials, demonstrating reduction of the resonator damping in all cases and hence the possibility for loss compensation. We find that the differential transmittance ?T/T can be negative in different SRR configurations, such as SRRs on the top of the gain substrate, gain in the SRR gap and gain covering the SRR structure, while in the fishnet metamaterial with gain ?T/T is positive. PMID:25402101

Huang, Zhixiang; Droulias, Sotiris; Koschny, Thomas; Soukoulis, Costas M

2014-11-17

309

Interleukin-18 Activates Skeletal Muscle AMPK and Reduces Weight Gain and Insulin Resistance in Mice  

PubMed Central

Circulating interleukin (IL)-18 is elevated in obesity, but paradoxically causes hypophagia. We hypothesized that IL-18 may attenuate high-fat diet (HFD)-induced insulin resistance by activating AMP-activated protein kinase (AMPK). We studied mice with a global deletion of the ?-isoform of the IL-18 receptor (IL-18R?/?) fed a standard chow or HFD. We next performed gain-of-function experiments in skeletal muscle, in vitro, ex vivo, and in vivo. We show that IL-18 is implicated in metabolic homeostasis, inflammation, and insulin resistance via mechanisms involving the activation of AMPK in skeletal muscle. IL-18R?/? mice display increased weight gain, ectopic lipid deposition, inflammation, and reduced AMPK signaling in skeletal muscle. Treating myotubes or skeletal muscle strips with IL-18 activated AMPK and increased fat oxidation. Moreover, in vivo electroporation of IL-18 into skeletal muscle activated AMPK and concomitantly inhibited HFD-induced weight gain. In summary, IL-18 enhances AMPK signaling and lipid oxidation in skeletal muscle implicating IL-18 in metabolic homeostasis. PMID:23670974

Lindegaard, Birgitte; Matthews, Vance B.; Brandt, Claus; Hojman, Pernille; Allen, Tamara L.; Estevez, Emma; Watt, Matthew J.; Bruce, Clinton R.; Mortensen, Ole H.; Syberg, Susanne; Rudnicka, Caroline; Abildgaard, Julie; Pilegaard, Henriette; Hidalgo, Juan; Ditlevsen, Susanne; Alsted, Thomas J.; Madsen, Andreas N.; Pedersen, Bente K.; Febbraio, Mark A.

2013-01-01

310

GD SDR Automatic Gain Control Characterization Testing  

NASA Technical Reports Server (NTRS)

The General Dynamics (GD) S-Band software defined radio (SDR) in the Space Communications and Navigation (SCAN) Testbed on the International Space Station (ISS) will provide experimenters an opportunity to develop and demonstrate experimental waveforms in space. The GD SDR platform and initial waveform were characterized on the ground before launch and the data will be compared to the data that will be collected during on-orbit operations. A desired function of the SDR is to estimate the received signal to noise ratio (SNR), which would enable experimenters to better determine on-orbit link conditions. The GD SDR does not have an SNR estimator, but it does have an analog and a digital automatic gain control (AGC). The AGCs can be used to estimate the SDR input power which can be converted into a SNR. Tests were conducted to characterize the AGC response to changes in SDR input power and temperature. This purpose of this paper is to describe the tests that were conducted, discuss the results showing how the AGCs relate to the SDR input power, and provide recommendations for AGC testing and characterization.

Nappier, Jennifer M.; Briones, Janette C.

2013-01-01

311

Recent results of the GAINS test flight  

NASA Astrophysics Data System (ADS)

A demonstration flight of the Global Atmosphere-ocean IN-situ System (GAINS) Prototype III balloon is scheduled to occur in early summer 2002. The 18-m diameter PIII superpressure balloon, built by GSSL, Inc., will float a 135-kg payload at 16 km. Performance of the SpectraTM envelope will be assessed over two day-night cycles. The payload consists of line-of-sight communications for transmitting GPS position, and monitored parameters on balloon and payload state and the internal and external thermal environments. Primary termination is by radio command with several independent backup termination systems. Safe operation of the balloon is ensured by an onboard transponder that keeps the balloon under active air traffic control. The balloon is tracked by an aircraft that will record communications from the balloon and instigate termination of the flight. Mobile ground stations positioned at the launch and recovery locations will also be capable of recording and terminating the flight. A suite of trajectory forecast tools has been developed based on radiosondes and winds from numerical weather models. A GPS surface reflection experiment for determining ocean surface winds will be tested on this platform. Physical and electronic integration of the radio and mechanical systems was completed over the last two years. Data and videos from the June flight will be presented.

Girz, C.

312

Elevational dependence of projected hydrologic changes in the San Francisco Estuary and watershed  

USGS Publications Warehouse

California's primary hydrologic system, the San Francisco Estuary and its upstream watershed, is vulnerable to the regional hydrologic consequences of projected global climate change. Previous work has shown that a projected warming would result in a reduction of snowpack storage leading to higher winter and lower spring-summer streamflows and increased spring-summer salinities in the estuary. The present work shows that these hydrologic changes exhibit a strong dependence on elevation, with the greatest loss of snowpack volume in the 1300-2700 m elevation range. Exploiting hydrologic and estuarine modeling capabilities to trace water as it moves through the system reveals that the shift of water in mid-elevations of the Sacramento river basin from snowmelt to rainfall runoff is the dominant cause of projected changes in estuarine inflows and salinity. Additionally, although spring-summer losses of estuarine inflows are balanced by winter gains, the losses have a stronger influence on salinity since longer spring-summer residence times allow the inflow changes to accumulate in the estuary. The changes in inflows sourced in the Sacramento River basin in approximately the 1300-2200 m elevation range thereby lead to a net increase in estuarine salinity under the projected warming. Such changes would impact ecosystems throughout the watershed and threaten to contaminate much of California's freshwater supply.

Knowles, N.; Cayan, D.R.

2004-01-01

313

Universal efficiency and gain computations for high-gain free-electron-laser amplifiers  

SciTech Connect

The free-electron-laser (FEL) equations are reduced to a set of one-dimensional, normalized equations that allow a universal (dimensional) analysis. In universal parameters, numerical integration of the FEL equations indicates a relatively constant saturated ponderomotive wave amplitude independent of both the normalized wiggler potential amplitude and the injected signal level. The constant ponderomotive wave amplitude and an empirical fit for the universal saturation length as a function of normalized wiggler potential amplitude and gain permits unnormalized design calculations for saturated power and saturated length over a wide parameter range. Tapering is considered by deriving analytical expressions for the intrinsic efficiency and taper length. Design values for a high-gain, high-efficiency, tapered amplifier at 280 and 560 GHz are presented.

Booske, J.H. (Department of Electrical and Computer Engineering, University of Wisconsin, Madison, Wisconsin 53706 (USA)); Bidwell, S.W.; Levush, B.; Antonsen, T.M. Jr.; Granatstein, V.L. (Laboratory for Plasma Research, University of Maryland, College Park, Maryland 20742 (USA))

1991-06-01

314

Plastic Responses to Elevated Temperature in Low and High Elevation Populations of Three Grassland Species  

PubMed Central

Local persistence of plant species in the face of climate change is largely mediated by genetic adaptation and phenotypic plasticity. In species with a wide altitudinal range, population responses to global warming are likely to differ at contrasting elevations. In controlled climate chambers, we investigated the responses of low and high elevation populations (1200 and 1800 m a.s.l.) of three nutrient-poor grassland species, Trifolium montanum, Ranunculus bulbosus, and Briza media, to ambient and elevated temperature. We measured growth-related, reproductive and phenological traits, evaluated differences in trait plasticity and examined whether trait values or plasticities were positively related to approximate fitness and thus under selection. Elevated temperature induced plastic responses in several growth-related traits of all three species. Although flowering phenology was advanced in T. montanum and R. bulbosus, number of flowers and reproductive allocation were not increased under elevated temperature. Plasticity differed between low and high elevation populations only in leaf traits of T. montanum and B. media. Some growth-related and phenological traits were under selection. Moreover, plasticities were not correlated with approximate fitness indicating selectively neutral plastic responses to elevated temperature. The observed plasticity in growth-related and phenological traits, albeit variable among species, suggests that plasticity is an important mechanism in mediating plant responses to elevated temperature. However, the capacity of species to respond to climate change through phenotypic plasticity is limited suggesting that the species additionally need evolutionary adaptation to adjust to climate change. The observed selection on several growth-related and phenological traits indicates that the study species have the potential for future evolution in the context of a warming climate. PMID:24901500

Frei, Esther R.; Ghazoul, Jaboury; Pluess, Andrea R.

2014-01-01

315

Harvesting Energy from the Counterbalancing (Weaving) Movement in Bicycle Riding  

PubMed Central

Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power. PMID:23112598

Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

2012-01-01

316

Harvesting energy from the counterbalancing (weaving) movement in bicycle riding.  

PubMed

Bicycles are known to be rich source of kinetic energy, some of which is available for harvesting during speedy and balanced maneuvers by the user. A conventional dynamo attached to the rim can generate a large amount of output power at an expense of extra energy input from the user. However, when applying energy conversion technology to human powered equipments, it is important to minimize the increase in extra muscular activity and to maximize the efficiency of human movements. This study proposes a novel energy harvesting methodology that utilizes lateral oscillation of bicycle frame (weaving) caused by user weight shifting movements in order to increase the pedaling force in uphill riding or during quick speed-up. Based on the 3D motion analysis, we designed and implemented the prototype of an electro-dynamic energy harvester that can be mounted on the bicycle's handlebar to collect energy from the side-to-side movement. The harvester was found to generate substantial electric output power of 6.6 mW from normal road riding. It was able to generate power even during uphill riding which has never been shown with other approaches. Moreover, harvesting of energy from weaving motion seems to increase the economy of cycling by helping efficient usage of human power. PMID:23112598

Yang, Yoonseok; Yeo, Jeongjin; Priya, Shashank

2012-01-01

317

Time gain influences adaptive visual-motor isometric force control.  

PubMed

This study examined the influence of time gain on the visual-motor control of isometric force. Time gain denotes the spatial length on the computer screen representing the unit of elapsed time of the force output, through which the time properties of the visually perceived force output can be compressed or extended. Five time gains and three force target waveforms (sinewave, brown noise, and straight line) with different time-dependent properties were tested in the experiment. The results revealed that time gain influenced task performance nonlinearly in a way that was dependent on the predictability of the target waveforms. In the sinewave target condition, there was a U-shaped modulation of time gain on the mean and variability of force error, and an inverted U-shaped modulation on the time-dependent structure of force variability. The time gain modulation effect was weaker in the brown noise target condition and absent in the constant force target condition. The results extend the effect of visual information gain regulation from force gain to time gain. The interaction between the time gain and target waveform supports the general proposition that the control of motor output is influenced by the interaction of different categories of constraints where the influence of visual information is dependent on the temporal properties and predictability of the force output and the task requirement. PMID:22278109

Hu, Xiaogang; Mazich, Molly M; Newell, Karl M

2012-04-01

318

Are videogame training gains specific or general?  

PubMed

Many recent studies using healthy adults document enhancements in perception and cognition from playing commercial action videogames (AVGs). Playing action games (e.g., Call of Duty, Medal of Honor) is associated with improved bottom-up lower-level information processing skills like visual-perceptual and attentional processes. One proposal states a general improvement in the ability to interpret and gather statistical information to predict future actions which then leads to better performance across different perceptual/attentional tasks. Another proposal claims all the tasks are separately trained in the AVGs because the AVGs and laboratory tasks contain similar demands. We review studies of action and non-AVGs to show support for the latter proposal. To explain transfer in AVGs, we argue that the perceptual and attention tasks share common demands with the trained videogames (e.g., multiple object tracking (MOT), rapid attentional switches, and peripheral vision). In non-AVGs, several studies also demonstrate specific, limited transfer. One instance of specific transfer is the specific enhancement to mental rotation after training in games with a spatial emphasis (e.g., Tetris). In contrast, the evidence for transfer is equivocal where the game and task do not share common demands (e.g., executive functioning). Thus, the "common demands" hypothesis of transfer not only characterizes transfer effects in AVGs, but also non-action games. Furthermore, such a theory provides specific predictions, which can help in the selection of games to train human cognition as well as in the design of videogames purposed for human cognitive and perceptual enhancement. Finally this hypothesis is consistent with the cognitive training literature where most post-training gains are for tasks similar to the training rather than general, non-specific improvements. PMID:24782722

Oei, Adam C; Patterson, Michael D

2014-01-01

319

Refractory intraoperative hypotension with elevated serum tryptase  

PubMed Central

Severe intraoperative hypotension has been reported in patients on angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists. We describe a patient on lisinopril who developed refractory intraoperative hypotension associated with increased serum tryptase level suggesting mast cell activation (allergic reaction). However, allergology workup ruled out an allergic etiology as well as mastocytosis, and hypotension recalcitrant to treatment was attributed to uninterrupted lisinopril therapy. Elevated serum tryptase was attributed to our patient's chronic renal insufficiency. PMID:25653920

Larson, Kelly J.; Divekar, Rohit D.; Butterfield, Joseph H.; Schwartz, Lawrence B.; Weingarten, Toby N.

2015-01-01

320

Elevated atmospheric carbon dioxide increases soil carbon  

Microsoft Academic Search

In a study funded by the U.S. Department of Energy's Office of Science, researchers from Argonne and Oak Ridge National Laboratories and Kansas State and Texas A&M Universities evaluated the collective results of earlier studies by using a statistical procedure called meta-analysis. They found that on average elevated CO2 increased soil carbon by 5.6 percent over a two to nine

Richard J Norby; Michael R Miller; Roser Matamala; THOMAS W. BOUTTON; CHARLES W. RICE; CLENTON E. OWENSBY

2005-01-01

321

Elevated cardiac enzymes due to mushroom poisoning.  

PubMed

Mushroom poisoning is an important reason of plant toxicity. Wild mushrooms that gathered from pastures and forests can be dangerous for human health. The clinical outcomes and symptoms of mushroom toxicity vary from mild gastrointestinal symptoms to acute multiple organ failure. Toxic effects to kidney and liver of amatoxin are common but cardiotoxic effects are unusual. In this case, we reported the cardiotoxic effect of amatoxin with the elevated troponin-I without any additional finding in electrocardiography, echocardiography and angiography. PMID:25567466

Avc?, Sema; Usul, Eren; Kavak, Nezih; Büyükcam, Fatih; Arslan, Engin Deniz; Genç, Selim; Özkan, Seda

2014-01-01

322

Creatine phosphokinase elevation exacerbated by levetiracetam therapy  

PubMed Central

A 19-year-old muscular male with a history of epilepsy presented following two convulsive events. Levetiracetam (LEV) was given as an additional therapy, resulting in a marked boost in creatine phosphokinase (CPK) that could not easily be explained by renal dysfunction or rhabdomyolysis alone. Levetiracetam discontinuation caused CPK levels to quickly normalize and should be considered in patients with persisting CPK elevations postconvulsive seizure.

Isaacson, Julia E.; Choe, Dongwhoon J.; Doherty, Michael J.

2014-01-01

323

Antarctic elevation change from 1992 to 1996  

PubMed

Satellite radar altimeter measurements show that the average elevation of the Antarctic Ice Sheet interior fell by 0.9 +/- 0.5 centimeters per year from 1992 to 1996. If the variability of snowfall observed in Antarctic ice cores is allowed for, the mass imbalance of the interior this century is only -0.06 +/- 0.08 of the mean mass accumulation rate. PMID:9774268

Wingham; Ridout; Scharroo; Arthern; Shum

1998-10-16

324

Solid lubricants for applications at elevated temperatures  

Microsoft Academic Search

Relative motion between mating surfaces at elevated temperatures often causes substantial material degradation due to friction\\u000a and wear. Conventionally, solid lubricants have been used to reduce wear damage and friction drag under extreme conditions\\u000a where liquid lubricants do not function properly. The recent trend towards higher operating temperatures in advanced power\\u000a generating systems, i.e. turbomachinery, gas turbines, and hot adiabatic

I. M. Allam

1991-01-01

325

Dopamine D4 receptors elevated in schizophrenia  

Microsoft Academic Search

ALTHOUGH the biological basis of schizophrenia is not known, possible causes include genetic defects, viruses1, amines2, brain structure and metabolism3-5, neuroreceptors6-8, and G proteins9. The hypothesis of dopamine overactivity in schizophrenia is based on the fact that neuroleptics block dopamine D2 receptors in direct relation to their clinical antipsychotic potencies10-11. Moreover, dopamine D2 or D2-like receptors are elevated in postmortem

Philip Seeman; Hong-Chang Guan; Hubert H. M. van Tol

1993-01-01

326

Refractivity estimation using multiple elevation angles  

Microsoft Academic Search

Estimation of the atmospheric refractivity is important for the prediction of radar performance. Surface or elevated trapping layers formed by the outflow of relatively dry and warm air over a cooler body of water often result in the refractive structure-supporting-convergence-zone-like behavior and multimodal effects. The propagation under such conditions can be very sensitive to even small changes in the vertical

Peter Gerstoft; L. Ted Rogers; William S. Hodgkiss; Lee J. Wagner

2003-01-01

327

Elevation of thromboxane in pressure wounds.  

PubMed

Arachidonic acid metabolites have been implicated as mediators of progressive dermal ischemia. Decubitus ulcer formation results from chronic mechanical pressure on the skin which results in a diminished blood supply to the skin and underlying tissues. To evaluate the role of thromboxanes in pressure wounds, we measured TxB2, a stable metabolite of TxA2, in spontaneously occurring pressure wounds on Greyhound dogs. In pressure wounds in which the skin was showing early signs of pressure necrosis but was still intact, elevated TxB2 concentrations were found in healthy appearing tissues immediately adjacent to the pressure wounds, in the inner edge of the wounds, and in the center of the wounds. Significantly greater TxB2 concentrations (P less than 0.05) were found in the center of the intact wounds versus the TxB2 concentrations in the inner edge of the wounds or in healthy appearing tissues adjacent to the wounds. In pressure wounds in which the center of the wound had ulcerated or had an eschar, elevated TxB2 concentrations were found in tissues in the inner edge of the wounds and in healthy appearing tissues immediately adjacent to the pressure wounds. These results demonstrate the occurrence of elevated thromboxane concentrations in and around spontaneously occurring pressure wounds. PMID:2762367

Vaughn, D M; Swaim, S F; Milton, J L

1989-07-01

328

Elevated-Temperature Tribology of Metallic Materials  

SciTech Connect

The wear of metals and alloys takes place in many forms, and the type of wear that dominates in each instance is influenced by the mechanics of contact, material properties, the interfacial temperature, and the surrounding environment. The control of elevated-temperature friction and wear is important for applications like internal combustion engines, aerospace propulsion systems, and metalworking equipment. The progression of interacting, often synergistic processes produces surface deformation, subsurface damage accumulation, the formation of tribolayers, and the creation of free particles. Reaction products, particularly oxides, play a primary role in debris formation and microstructural evolution. Chemical reactions are known to be influenced by the energetic state of the exposed surfaces, and that surface energy is in turn affected by localized deformation and fracture. At relatively low temperatures, work-hardening can occur beneath tribo-contacts, but exposure to high temperatures can modify the resultant defect density and grain structure to affect the mechanisms of re-oxidation. As research by others has shown, the rate of wear at elevated temperatures can either be enhanced or reduced, depending on contact conditions and nature of oxide layer formation. Furthermore, the thermodynamic driving force for certain chemical reactions is moderated by kinetics and microstructure. The role of deformation, oxidation, and tribo-corrosion in the elevated temperature tribology of metallic alloys will be exemplified by three examples involving sliding wear, single-point abrasion, and repetitive impact plus slip.

Blau, Peter Julian [ORNL

2010-01-01

329

Digital elevation modelling using ASTER stereo imagery.  

PubMed

Digital elevation model (DEM) in recent times has become an integral part of national spatial data infrastructure of many countries world-wide due to its invaluable importance. Although DEMs are mostly generated from contours maps, stereo aerial photographs and air-borne and terrestrial laser scanning, the stereo interpretation and auto-correlation from satellite image stereo-pairs such as with SPOT, IRS, and relatively new ASTER imagery is also an effective means of producing DEM data. In this study, terrain elevation data were derived by applying photogrammetric process to ASTER stereo imagery. Also, the quality ofDEMs produced from ASTER stereo imagery was analysed by comparing it with DEM produced from topographic map at a scale of 1:50,000. While analyzing the vertical accuracy of the generated ASTER DEM, fifty ground control points were extracted from the map and overlaid on the DEM. Results indicate that a root-mean-square error in elevation of +/- 14 m was achieved with ASTER stereo image data of good quality. The horizontal accuracy obtained from the ground control points was 14.77, which is within the acceptable range of +/- 7m to +/- 25 m. The generated (15 m) DEM was compared with a 20m, 25m, and a 30 m pixel DEM to the original map. In all, the results proved that, the 15 m DEM conform to the original map DEM than the others. Overall, this analysis proves that, the generated digital terrain model, DEM is acceptable. PMID:21114113

Forkuo, Eric Kwabena

2010-04-01

330

Methods for structural design at elevated temperatures  

NASA Technical Reports Server (NTRS)

A procedure which can be used to design elevated temperature structures is discussed. The desired goal is to have the same confidence in the structural integrity at elevated temperature as the factor of safety gives on mechanical loads at room temperature. Methods of design and analysis for creep, creep rupture, and creep buckling are presented. Example problems are included to illustrate the analytical methods. Creep data for some common structural materials are presented. Appendix B is description, user's manual, and listing for the creep analysis program. The program predicts time to a given creep or to creep rupture for a material subjected to a specified stress-temperature-time spectrum. Fatigue at elevated temperature is discussed. Methods of analysis for high stress-low cycle fatigue, fatigue below the creep range, and fatigue in the creep range are included. The interaction of thermal fatigue and mechanical loads is considered, and a detailed approach to fatigue analysis is given for structures operating below the creep range.

Ellison, A. M.; Jones, W. E., Jr.; Leimbach, K. R.

1973-01-01

331

Angiotensin AT(2) receptor contributes towards gender bias in weight gain.  

PubMed

Obesity is a major disease condition, in turn leading to pathological changes collectively recognized as metabolic syndrome. Recently angiotensin receptor AT(2)R has been associated negatively with body weight (BW) gain in male mice. However, the gender differences in AT(2)R and BW changes have not been studied. To understand the gender based role of AT(2)R involving BW changes, we fed male and female wild type (WT) and AT(2)R knock out (AT(2)KO) mice with C57BL6 background with high fat diet (HFD) for 16 weeks. The male AT(2)KO had higher HFD calorie intake (WT: 1280±80; AT(2)KO:1680±80 kcal) but gained less BW compared with the WT (WT: 13; AT(2)KO: 6 g). Contrary to the male animals, the female AT(2)KO mice with equivalent caloric intake (WT: 1424±48; AT(2)KO:1456±80 kcal) gained significantly more BW than the WT mice (WT: 9 g; AT(2)KO: 15 g). The male AT(2)KO on HFD displayed lower plasma insulin level, less impaired glucose tolerance (GT), and higher plasma T3 compared with WT males on HFD; whereas the female AT(2)KO mice on HFD showed elevated levels of plasma insulin, more impaired GT, lower plasma T3 and higher free fatty acid and hepatic triglycerides compared with WT females on HFD. Interestingly, compared with WT, AT(2)KO female mice had significantly lower estrogen, which was further reduced by HFD. These results suggest that AT(2)R in female mice via potentially regulating estrogen may have protective role against BW gain and impaired glucose tolerance and lipid metabolism. PMID:23341867

Samuel, Preethi; Khan, Mohammad Azhar; Nag, Sourashish; Inagami, Tadashi; Hussain, Tahir

2013-01-01

332

Angiotensin AT2 Receptor Contributes towards Gender Bias in Weight Gain  

PubMed Central

Obesity is a major disease condition, in turn leading to pathological changes collectively recognized as metabolic syndrome. Recently angiotensin receptor AT2R has been associated negatively with body weight (BW) gain in male mice. However, the gender differences in AT2R and BW changes have not been studied. To understand the gender based role of AT2R involving BW changes, we fed male and female wild type (WT) and AT2R knock out (AT2KO) mice with C57BL6 background with high fat diet (HFD) for 16 weeks. The male AT2KO had higher HFD calorie intake (WT: 1280±80; AT2KO:1680±80 kcal) but gained less BW compared with the WT (WT: 13; AT2KO: 6 g). Contrary to the male animals, the female AT2KO mice with equivalent caloric intake (WT: 1424±48; AT2KO:1456±80 kcal) gained significantly more BW than the WT mice (WT: 9 g; AT2KO: 15 g). The male AT2KO on HFD displayed lower plasma insulin level, less impaired glucose tolerance (GT), and higher plasma T3 compared with WT males on HFD; whereas the female AT2KO mice on HFD showed elevated levels of plasma insulin, more impaired GT, lower plasma T3 and higher free fatty acid and hepatic triglycerides compared with WT females on HFD. Interestingly, compared with WT, AT2KO female mice had significantly lower estrogen, which was further reduced by HFD. These results suggest that AT2R in female mice via potentially regulating estrogen may have protective role against BW gain and impaired glucose tolerance and lipid metabolism. PMID:23341867

Samuel, Preethi; Khan, Mohammad Azhar; Nag, Sourashish; Inagami, Tadashi; Hussain, Tahir

2013-01-01

333

The effects of neural gain on attention and learning  

PubMed Central

Attention is commonly thought to be manifest through local variations in neural gain. However, what would be the effects of brain-wide changes in gain? Here, we hypothesize that global fluctuations in gain modulate the breadth of attention, and thus, the degree to which processing is focused on aspects of the environment to which one is predisposed to attend. In accordance with this hypothesis, we show that measures of pupil diameter, which are thought to track levels of LC-NE activity and neural gain, are correlated with the degree to which learning is focused on stimulus dimensions that individual human participants are more predisposed to process. In support of our interpretation of this effect in terms of global changes in gain, we further show that the measured pupillary and behavioral variables are strongly correlated with global changes in the strength and clustering of functional connectivity, as brain-wide fluctuations of gain would predict. PMID:23770566

Eldar, Eran; Cohen, Jonathan D.; Niv, Yael

2013-01-01

334

Femtosecond optical gain in strongly confined quantum dots  

NASA Astrophysics Data System (ADS)

Optical gain was found in strongly confined CdSe quantum dots. As a result of a multitude of one- and two-electron-hole pair transitions, the gain region is broad and quasi-continuous and stretches below the absorption edge. We present a model for gain in a quasi-zero-dimensional quantum confined semiconductor system that agrees well with the femtosecond experiments.

Giessen, H.; Woggon, U.; Fluegel, B.; Mohs, G.; Hu, Y. Z.; Koch, S. W.; Peyghambarian, N.

1996-07-01

335

Gain-scheduled filtering for time-varying discrete systems  

Microsoft Academic Search

This paper deals with the design of gain-scheduled filters, whose state-space realization depends on real-time parameters of plants. Similar to well-recognized advantages of gain-scheduled controllers in control theory, gain-scheduled filters are expected to provide enhanced performance in comparison with customary nonadjustable filters. Our construction technique is based on nonlinear fractional transformation (NFT) representations of systems that are a generalization of

Nguyen Thien Hoang; Hoang Duong Tuan; Pierre Apkarian; Shigeyuki Hosoe

2004-01-01

336

Fuzzy gain scheduling for flutter suppression in unmanned aerial vehicles  

Microsoft Academic Search

This article describes the creation of a robust fuzzy gain scheduler for flutter suppression in the open-loop response of a non-minimum phase aeroservoelastic UAV (unmanned aerial vehicle) model. Two sets of Takagi-Sugeno (TS) fuzzy rules were constructed for gain scheduling: one set for system identification of the approximate plant matrices and one for full state feedback control using interpolated gains.

Ellen Applebaum

2003-01-01

337

Evaluation of balloon trajectory forecast routines for GAINS  

Microsoft Academic Search

The Global Air-ocean IN-situ System (GAINS) is a global observing system designed to augment current environmental observing and monitoring networks. GAINS is a network of long-duration, stratospheric platforms that carry onboard sensors and hundreds of dropsondes to acquire meteorological, air chemistry, and climate data over oceans and in remote land regions of the globe. Although GAINS platforms will include balloons

R. Collander; C. Girz

2002-01-01

338

Dynamic gain compensation in saturated erbium-doped fiber amplifiers  

Microsoft Academic Search

Dynamic compensation of low-frequency gain fluctuations in saturated erbium-doped fiber amplifiers is demonstrated. This compensation, based on a simple feedback-loop scheme makes it possible to reduce transient gain fluctuations efficiently across the whole amplifier bandwidth using only a low-power optical feedback signal. Such an, automatic gain control technique could be applied to suppress data packet interference due to traffic bursts

E. Desurvire; M. Zirngibl; H. M. Presby; D. Digiovanni

1991-01-01

339

Erbium-doped fiber amplifier with flattened gain spectrum  

Microsoft Academic Search

An optical notch filter was incorporated within the length of all erbium-doped fiber amplifier. Careful choice of the filter characteristics and location made it possible to enhance the amplifier gain at wavelengths around 1550 nm. An amplifier with 27-dB gain and 33-nm bandwidth was demonstrated. The saturation characteristics of the amplifier were uniform across its gain spectrum, making it ideal

M. Tachibana; R. I. Laming; P. R. Morkel; D. N. Payne

1991-01-01

340

Absolute gain measurement by the image method under mismatched condition  

NASA Technical Reports Server (NTRS)

Purcell's image method for measuring the absolute gain of an antenna is particularly attractive for small test antennas. The method is simple to use and utilizes only one antenna with a reflecting plane to provide an image for the receiving antenna. However, the method provides accurate results only if the antenna is matched to its waveguide. In this paper, a waveguide junction analysis is developed to determine the gain of an antenna under mismatched condition. Absolute gain measurements for two standard gain horn antennas have been carried out. Experimental results agree closely with published data.

Lee, Richard Q.; Baddour, Maurice F.

1987-01-01

341

Elevated CO2 and O3 Alter Productivity and Carbon Storage in Northern Temperate Forests: Results from Aspen FACE  

NASA Astrophysics Data System (ADS)

Three northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2) and/or tropospheric ozone (O3) for 11 years, advancing from open-grown seedlings <0.25 m in height at the beginning to the experiment to closed-canopy stands that were >8 m tall. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment. In addition, we estimated cumulative net primary productivity (NPP) during the experiment and used these data to gain further insight into forest C cycling in two ways. First, we tested several canopy productivity models to understand variation in cumulative NPP. Second, we compared cumulative NPP to ecosystem C storage. Elevated CO2 enhanced ecosystem carbon (C) storage by 11%, but elevated O3 decreased ecosystem C storage by 9%. There was little variation in treatment effects on C storage across communities and no significant interactions between CO2 and O3 for any major C pools. Tree C storage increased 44% under elevated CO2 and decreased 15% under elevated O3. Neither CO2 nor O3 affected the total amount of C in the top 1 m of mineral soil. However, soil C content within the top 0.1 m of mineral soil was lower under elevated O3, whereas soil C at 0.1 to 0.2 m and 0.4 to 0.5 m in depth were lower under elevated CO2. Cumulative NPP was 42% greater under elevated CO2, 11% lower under elevated O3, and was a strong predictor of variation in C storage in plants and organic soil (n = 36, r2 = 0.96). Tree productivity comprised 95% of cumulative NPP. Stands with more cumulative canopy N (g foliar N m-2 of ground area) had greater cumulative tree productivity, but N productivity (tree productivity per canopy N) decreased as canopy N accrued. Thus, elevated CO2 increased cumulative NPP because of a 28% increase in canopy N and a 28% increase in N productivity, while elevated O3 did not impact N productivity and lowered tree productivity only through a 21% decrease in canopy N. Because N productivity decreased as canopy N accrued, the difference in canopy N between ambient and elevated O3 had a gradually smaller influence on NPP through time as the stands became more developed, eventually eliminating the O3 effect. In comparison, variation in mineral soil C content was not positively related to cumulative NPP and the effects of CO2 and O3 on this important ecosystem C pool remain poorly understood..

Talhelm, A. F.; Pregitzer, K.; Kubiske, M.; Zak, D.; Campany, C.; Burton, A.

2013-12-01

342

29 CFR 780.707 - Establishments “commonly recognized” as country elevators.  

Code of Federal Regulations, 2010 CFR

...ACT Employment by Small Country Elevators Within Area of Production; Exemption From Overtime Pay Requirements Under Section 13...elevators, public terminal and subterminal grain elevators, wheat flour mill elevators, non-elevator-type bulk grain...

2010-07-01

343

Effective Gain Measurement in Quantum Cascade Lasers: A new method to measure gain in Quantum Cascade Lasers  

NSDL National Science Digital Library

Gain and Loss are the fundamental factors contributing to laser effectiveness. Simply put, the gain is the light produced by stimulated emission and loss is then the light lost. This can happen if a photon hits an electron in a low energy level state and the electron absorbs the energy and moves to a higher energy level state. It can also happen when light escapes the laser cavity. Lasing is the condition when the gain exceeds the loss. It is very important to know the gain to see how effective your laser really is. The traditional Hakki-Paoli Method was found to be ineffective for measuring gain in quantum cascade lasers. A new, more effective method of measuring gain in quantum cascade lasers was developed and tested.

Haslam, Bryan

2005-08-05

344

Elevated Wintertime Ozone in Utah's Uinta Basin  

NASA Astrophysics Data System (ADS)

Seemingly anomalous elevated wintertime ozone (O3) levels were first observed in Wyoming's Upper Green River Basin (UGRB) in 2005 and have been recorded most in subsequent winters. While research continues, it has been hypothesized that the unacceptable levels are a unique combination of stagnant meteorology, enhanced insolation due to relatively high elevations and snow increased albedo, and abundant precursor sources owing to the region's recent rapid expansion of oil and gas exploration and production. The UGRB area has over 4,700 recorded gas/oil wells and sits mostly in rural Sublette County which has an estimated population of 7,925, an area of 12,644 km2, and a basin floor elevation around 2200 m asl, surrounded on three sides with mountains up to 4,200 km asl. Similarly, the Uinta Basin in northeastern Utah is a rural area prone to frequent low-level wintertime inversion episodes and persistent snow cover, with an expanding economy significantly based on gas and oil development and production (approximately 11,500 wells, with an estimated 17,000 more planned in the future years). The Basin lies primarily in Duchesne and Uintah Counties which have a combined population of approximately 51,200 and an area of about 19,982 km2. The floor of the Basin has a typical elevation around 1,560 m asl and is surrounded by mountains up to 4,120 m asl. Ambient measurements at four sites in the winter of 2009-2010 found many instances of ozone concentrations well above the current U.S. National Ambient Air Quality Standard (NAAQS; 75 ppb, 8-hr average, 4th highest value). To more fully characterize the behavior and geographical extent of the Uinta Basin's wintertime O3 issue, the Uintah Impact Mitigation Special Service District (UIMSSD) funded a study which included deploying 10 portable O3 monitors (2B Technologies, Inc., Model 205, Dual Beam) throughout the Basin. Furthermore, cooperative partners including the USEPA, BLM, UDAQ, NPS, and Golder Associates provided access to an additional six monitoring locations within the Basin. The sites were operated from late December 2010 through mid-March 2011. Several stagnant, inversion episodes and associated periods of Basin-wide elevated ozone were captured. The highest 1-hr O3 concentration observed was 149.0 ppb, with 12 of the total 16 sites recording 1-hr values greater than 100 ppb. Of the 16 sites, only four were found not to exceed the current NAAQS regulation. The highest 8-hr averaged concentration recorded was 139.1 ppb. However, the U.S. standards specify that an area is regulated at the 4th highest values and the maximum value under this criterion during the observed winter period was 121.6 ppb. Two sites exceeded the NAAQS 25 days over the three month observation period, while five other locations exceed the NAAQS between 18 and 22 times. The sites with the highest O3 concentrations and the greatest number of daily exceedances were generally associated with the highest density of known oil and/or gas well locations. The sites with the fewest number of exceedances were at higher elevations or geographically peripheral locations.

Martin, R. S.; Moore, K. D.; Hill, S.; Harper, K.

2011-12-01

345

Astronomers Gain Clues About Fundamental Physics  

NASA Astrophysics Data System (ADS)

An international team of astronomers has looked at something very big -- a distant galaxy -- to study the behavior of things very small -- atoms and molecules -- to gain vital clues about the fundamental nature of our entire Universe. The team used the National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT) to test whether the laws of nature have changed over vast spans of cosmic time. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF (Click on image for GBT gallery) "The fundamental constants of physics are expected to remain fixed across space and time; that's why they're called constants! Now, however, new theoretical models for the basic structure of matter indicate that they may change. We're testing these predictions." said Nissim Kanekar, an astronomer at the National Radio Astronomy Observatory (NRAO), in Socorro, New Mexico. So far, the scientists' measurements show no change in the constants. "We've put the most stringent limits yet on some changes in these constants, but that's not the end of the story," said Christopher Carilli, another NRAO astronomer. "This is the exciting frontier where astronomy meets particle physics," Carilli explained. The research can help answer fundamental questions about whether the basic components of matter are tiny particles or tiny vibrating strings, how many dimensions the Universe has, and the nature of "dark energy." The astronomers were looking for changes in two quantities: the ratio of the masses of the electron and the proton, and a number physicists call the fine structure constant, a combination of the electron charge, the speed of light and the Planck constant. These values, considered fundamental physical constants, once were "taken as time independent, with values given once and forever" said German particle physicist Christof Wetterich. However, Wetterich explained, "the viewpoint of modern particle theory has changed in recent years," with ideas such as superstring theory and extra dimensions in spacetime calling for the "constants" to change over time, he said. The astronomers used the GBT to detect and study radio emissions at four specific frequencies between 1612 MHz and 1720 MHz coming from hydroxyl (OH) molecules in a galaxy more than 6 billion light-years from Earth, seen as it was at roughly half the Universe's current age. Each of the four frequencies represents a specific change in the energy level of the molecule. The exact frequency emitted or absorbed when the molecule undergoes a transition from one energy level to another depends on the values of the fundamental physical constants. However, each of the four frequencies studied in the OH molecule will react differently to a change in the constants. That difference is what the astronomers sought to detect using the GBT, which, Kanekar explained, is the ideal telescope for this work because of its technical capabilities and its location in the National Radio Quiet Zone, where radio interference is at a minimum. "We can place very tight limits on changes in the physical constants by studying the behavior of these OH molecules at a time when the Universe was only about half its current age, and comparing this result to how the molecules behave today in the laboratory," said Karl Menten of the Max-Planck Institute for Radioastronomy in Germany. Wetterich, a theorist, welcomes the new capability, saying the observational method "seems very promising to obtain perhaps the most accurate values for such possible time changes of the constants." He pointed out that, while some theoretical models call for the constants to change only in the early moments after the Big Bang, models of the recently-discovered, mysterious "dark energy" that seems to be accelerating the Universe's expansion call for changes "even in the last couple of billion years." "Only observations can tell," he said. This research ties together the theoretical and observation

2005-12-01

346

47 CFR 25.205 - Minimum angle of antenna elevation.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Minimum angle of antenna elevation. 25.205 Section 25.205...Technical Standards § 25.205 Minimum angle of antenna elevation. (a) Earth station antennas shall not normally be authorized...

2013-10-01

347

47 CFR 25.205 - Minimum angle of antenna elevation.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Minimum angle of antenna elevation. 25.205 Section 25.205...Technical Standards § 25.205 Minimum angle of antenna elevation. (a) Earth station antennas shall not normally be authorized...

2014-10-01

348

47 CFR 25.205 - Minimum angle of antenna elevation.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Minimum angle of antenna elevation. 25.205 Section 25.205...Technical Standards § 25.205 Minimum angle of antenna elevation. (a) Earth station antennas shall not normally be authorized...

2011-10-01

349

22. DRAWING #8 OF 15, FRONT AND REAR ELEVATIONS, CANOPY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. DRAWING #8 OF 15, FRONT AND REAR ELEVATIONS, CANOPY ROOF PLAN AND CANOPY DETAIL, AND ELEVATIONS OF NEW TOILETS - U. S. Post Office, Custom House & Courthouse, 401 Center Street, Fernandina Beach, Nassau County, FL

350

SHADED RELIEF, HILLSHADE, DIGITAL ELEVATION MODEL (DEM), ARIZONA  

EPA Science Inventory

Shaded relief of the state of Arizona developed from 1-degree US Geological Survey (USGS) Digital Elevation Models (DEMs). DEM is a terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. ...

351

SHADED RELIEF, HILLSHADE, DIGITAL ELEVATION MODEL (DEM), NEVADA  

EPA Science Inventory

Shaded relief of the state of Nevada developed from 1-degree US Geological Survey (USGS) Digital Elevation Models (DEMs). DEM is a terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. ...

352

5. American elevator looking east barely visible behind American malt ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. American elevator looking east barely visible behind American malt house with Russell-Miller flour mill to right (now Eonacara and idle). - American Elevator, 87 Childs Street, Buffalo, Erie County, NY

353

49 CFR 213.57 - Curves; elevation and speed limitations.  

Code of Federal Regulations, 2013 CFR

...Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.57 Curves; elevation and speed limitations. (a) The maximum elevation of the outside rail of a...

2013-10-01

354

2. BRICK END ELEVATION WITH X VENTILATORS, REDPAINTED GABLE WITH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. BRICK END ELEVATION WITH X VENTILATORS, RED-PAINTED GABLE WITH WHITE STARS AND A DOORWAY HOOD. ALSO SHOWS PORTION OF REAR ELEVATION WITH X VENTILATORS - Decorated Red Barn (1852), State Route 100 vicinity, Pottstown, Montgomery County, PA

355

28 CFR 36.404 - Alterations: Elevator exemption.  

Code of Federal Regulations, 2012 CFR

... § 36.404 Alterations: Elevator exemption. (a) This section...require the installation of an elevator in an altered facility...common ownership or common control or developed either as one...the altered facility has an...

2012-07-01

356

28 CFR 36.404 - Alterations: Elevator exemption.  

Code of Federal Regulations, 2010 CFR

... § 36.404 Alterations: Elevator exemption. (a) This section...require the installation of an elevator in an altered facility...common ownership or common control or developed either as one...the altered facility has an...

2010-07-01

357

28 CFR 36.404 - Alterations: Elevator exemption.  

Code of Federal Regulations, 2014 CFR

... § 36.404 Alterations: Elevator exemption. (a) This section...require the installation of an elevator in an altered facility...common ownership or common control or developed either as one...the altered facility has an...

2014-07-01

358

28 CFR 36.404 - Alterations: Elevator exemption.  

Code of Federal Regulations, 2013 CFR

... § 36.404 Alterations: Elevator exemption. (a) This section...require the installation of an elevator in an altered facility...common ownership or common control or developed either as one...the altered facility has an...

2013-07-01

359

28 CFR 36.404 - Alterations: Elevator exemption.  

Code of Federal Regulations, 2011 CFR

... § 36.404 Alterations: Elevator exemption. (a) This section...require the installation of an elevator in an altered facility...common ownership or common control or developed either as one...the altered facility has an...

2011-07-01

360

Dual swing-up elevator well drilling apparatus  

SciTech Connect

A well drilling apparatus includes a first swing-up elevator platform on which the mast structure is pivotally mounted. After the mast structure has been raised to its erect position, the first elevator platform is elevated to carry the mast structure to a high operational level. A second swing-up elevator platform is provided to carry the drawworks to the same high level at which the two elevator platforms are coupled together to form the working floor. All of the raising and elevating operations can be accomplished with power supplied by the drawworks. The elevator platforms may be lowered after the drilling operation has been accomplished without interfering with any control valve structures that have been placed on the wellhead while the structure was at its raised operational level; the swing-up elevator platforms swing down in opposite directions over any such valve structure.

Ahmad, H.; Vorarittinapa, T.

1984-09-18

361

20. An elevation view of the north side of the ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. An elevation view of the north side of the southern portion of the upper grain conveyor system on Elevator and Silo Complex B (1932). - Quaker Oats Cereal Factory, Southeast corner of Broadway & Mill Streets, Akron, Summit County, OH

362

6. This is an elevation view of the upper grain ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. This is an elevation view of the upper grain conveyor bridge (1940) connecting the 'Landmark' with Elevator and Silo Complex B. - Quaker Oats Cereal Factory, Southeast corner of Broadway & Mill Streets, Akron, Summit County, OH

363

8. Peavey Duluth Terminal Elevator spout floor with mayo distribution ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. Peavey Duluth Terminal Elevator spout floor with mayo distribution spouts from northeast corner. - Peavey Duluth Terminal Elevator, Workhouse, South side of first slip, north from outer end of Rice's Point, east of Garfield Avenue, Duluth, St. Louis County, MN

364

7. Peavey Duluth Terminal Elevator spout floorgrain dryer on north ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Peavey Duluth Terminal Elevator spout floor-grain dryer on north wall. - Peavey Duluth Terminal Elevator, Workhouse, South side of first slip, north from outer end of Rice's Point, east of Garfield Avenue, Duluth, St. Louis County, MN

365

Elevation puts moral values into action  

E-print Network

the ‘‘Oprah Winfrey Show’’ in which a music teacher mentored a young man from an impoverished background and played a major part in turning him away from a potential life of crime. Compared to participants who watched a neutral control clip or one eliciting... and consequently may have felt under some obligation to make it up to the experimenter. Materials Film clips for emotion induction. In the experimental condition, participants watched the 7-minute Oprah Winfrey clip previ- ously used to induce elevation (Silvers...

Schnall, Simone; Roper, Jean

2012-01-01

366

Elevation Derivatives for Mojave Desert Tortoise Habitat  

USGS Publications Warehouse

This report describes the methods used to derive various elevation-derivative grids that were inputted to the Mojave Desert Tortoise Habitat model (L. Gass and others, unpub. data). These grids, which capture information on surface roughness and topographic characteristics, are a subset of the environmental datasets evaluated for the tortoise habitat model. This habitat model is of major importance to the U.S. Fish and Wildlife Service, which is charged with management of this threatened population, including relocating displaced tortoises to areas identified as suitable habitat.

Wallace, Cynthia S.A.; Gass, Leila

2008-01-01

367

Void evolution in polycarbonate at elevated temperatures  

SciTech Connect

The void evolution in polycarbonate (PC) at elevated temperatures was investigated. Internal cylindrical cracks and voids were induced in PC by Nd-YAG laser irradiation. During the annealing at temperatures of 177-197 deg. C, the spherical void grows to a maximum size, which then decreases, and is finally leveling off. A model of void evolution based on the evaporation and condensation mechanisms for growth and shrinkage is proposed. The theoretical predictions are in good agreement with the experimental data. The activation energies of evaporation and condensation processes are determined to be 477.31 and 611.49 kJ/mol, respectively.

Chen, Y. H.; Li, C. L.; Lee, Sanboh [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Kuo Feng Chou [Department of Biomedical Engineering, Yuanpei University, Hsinchu, Taiwan (China)

2011-08-15

368

Charcoal and activated carbon at elevated pressure  

SciTech Connect

High quality charcoal has been produced with very high yields of 50% to 60% from macadamia nut and kukui nut shells and of 44% to 47% from Eucalyptus and Leucaena wood in a bench scale unit at elevated pressure on a 2 to 3 hour cycle, compared to commercial practice of 25% to 30% yield on a 7 to 12 day operating cycle. Neither air pollution nor tar is produced by the process. The effects of feedstock pretreatments with metal additives on charcoal yield are evaluated in this paper. Also, the influences of steam and air partial pressure and total pressure on yields of activated carbon from high yield charcoal are presented.

Antal, M.J. Jr.; Dai, Xiangfeng; Norberg, N. [Univ. of Hawaii at Manoa, Honolulu, HI (United States)] [and others

1995-12-01

369

Pathology Case Study: Elevated Tricyclic Antidepressant Levels  

NSDL National Science Digital Library

This is a case study presented by the University of Pittsburgh Department of Pathology in which a 38-year-old woman was found to have "elevated tricyclic antidepressant levels during a routine clinic visit." Visitors are given the physical exam notes, electrocardiography, and laboratory tests, including images, and are given the opportunity to diagnose the patient. This is an excellent resource for students in the health sciences to familiarize themselves with using patient history and laboratory results to diagnose disease. It is also a helpful site for educators to use to introduce or test student learning in pathology and clinical chemistry.

Harrison, James; Rao, K. N.; Tamama, Kenichi

2008-12-11

370

Range Safety Flight Elevation Limit Calculation Software  

NASA Technical Reports Server (NTRS)

This program was developed to fill a need within the Wallops Flight Facility workflow for automation of the development of vertical plan limit lines used by flight safety officers during the conduct of expendable launch vehicle missions. Vertical plane present-position-based destruct lines have been used by range safety organizations at numerous launch ranges to mitigate launch vehicle risks during the early phase of flight. Various ranges have implemented data submittal and processing workflows to develop these destruct lines. As such, there is significant prior art in this field. The ElLimits program was developed at NASA's Wallops Flight Facility to automate the process for developing vertical plane limit lines using current computing technologies. The ElLimits program is used to configure launch-phase range safety flight control lines for guided missiles. The name of the program derives itself from the fundamental quantity that is computed - flight elevation limits. The user specifies the extent and resolution of a grid in the vertical plane oriented along the launch azimuth. At each grid point, the program computes the maximum velocity vector flight elevation that can be permitted without endangering a specified back-range location. Vertical plane x-y limit lines that can be utilized on a present position display are derived from the flight elevation limit data by numerically propagating 'streamlines' through the grid. The failure turn and debris propagation simulation technique used by the application is common to all of its analysis options. A simulation is initialized at a vertical plane grid point chosen by the program. A powered flight failure turn is then propagated in the plane for the duration of the so-called RSO reaction time. At the end of the turn, a delta-velocity is imparted, and a ballistic trajectory is propagated to impact. While the program possesses capability for powered flight failure turn modeling, it does not require extensive user inputs of vehicle characteristics (e.g., thrust and aerodynamic data), nor does it require reams of turn data after the traditional fashion of the Air Force ranges. The program requires a nominal trajectory table (time, altitude, range, velocity, and flight elevation) and makes heavy use of it to initialize and model a failure turn.

Lanzi, Raymond J

2014-01-01

371

Transient elevation of the ipsilateral hemidiaphragm associated with pneumonia  

PubMed Central

Seventeen children with lobar or segmental pneumonia and ispilateral elevation of the diaphragm are described. These children did not differ significantly with respect to clinical and laboratory findings from their counterparts with pneumonia but without elevation of the hemidiaphragm. The elevation was transient and resolved by the time the repeat chest x-ray was taken six to eight weeks later. PMID:22059187

Fretzayas, Andrew; Moustaki, Maria; Nicolaidou, Polyxeni; Alexopoulou, Efthimia; Priftis, Konstantinos N

2011-01-01

372

5. View West. West side and rear elevations of c. ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. View West. West side and rear elevations of c. 1890 first rear addition; partial north rear elevation of c. 1900 side ell addition; and north rear and west side elevation of final rear addition of c. 1940. - Vaughn Chevrolet Building, 101-109 East Main Street, Monongahela, Washington County, PA

373

Design and implementation of a statechart based reconfigurable elevator controller  

Microsoft Academic Search

This paper presents a simple and clear method to design and implement a reconfigurable elevator controller using an FPGA, which can be implemented for an elevator with any (N) number of floors, with specified inputs and outputs. A model based design approach was followed. We started from a state chart model developed for a prototype elevator with three floors. Extension

H. P. A. P. Jayawardana; H. W. K. M. Amarasekara; P. T. S. Peelikumbura; W. A. K. C. Jayathilaka; S. G. Abeyaratne; S. D. Dewasurendra

2011-01-01

374

20. Elevator no. 2: stairway, doorway and exterior north wall ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Elevator no. 2: stairway, doorway and exterior north wall of control room (floor 5, elevated to right), with control shafts and turnhead distributor, facing east - Washburn Crosby Company Elevators No. 2 & 3, 900 & 1000 Second Avenue, South, Minneapolis, Hennepin County, MN

375

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.  

Code of Federal Regulations, 2012 CFR

...penetration for a stairway or elevator exceeds one deck, the integrity...penetration for a stairway or elevator involves only one deck, the...bulkheads of the same fire control boundary rating as the deck...in the way of stairways or elevators need not be assured....

2012-10-01

376

Devising a Formal Specification for an Elevator Controller  

E-print Network

Devising a Formal Specification for an Elevator Controller Technical Report UMCIS­1994­10 H. Conrad for an Elevator Controller H. Conrad Cunningham, Viren R. Shah, and Shu Shen Department of Computer the requirements for the controlling mechanism for a system of N separate elevators, each of which can visit any

Cunningham, Conrad

377

Logical Control of an Elevator with Defeasible Logic  

E-print Network

Logical Control of an Elevator with Defeasible Logic Michael A. Covington Senior Member, IEEE for assis- tance and encouragement. #12;Abstract The elevator control program described in this journal for controlling an elevator. They assume that a separate routine, outside the theorem prover, maintains a queue

Covington, Michael A.

378

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.  

Code of Federal Regulations, 2014 CFR

...penetration for a stairway or elevator exceeds one deck, the integrity...penetration for a stairway or elevator involves only one deck, the...bulkheads of the same fire control boundary rating as the deck...in the way of stairways or elevators need not be assured....

2014-10-01

379

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.  

Code of Federal Regulations, 2013 CFR

...penetration for a stairway or elevator exceeds one deck, the integrity...penetration for a stairway or elevator involves only one deck, the...bulkheads of the same fire control boundary rating as the deck...in the way of stairways or elevators need not be assured....

2013-10-01

380

7 CFR 800.25 - Required elevator and merchandising records.  

Code of Federal Regulations, 2012 CFR

...State that owns or operates an elevator and every merchandiser...lots of grain for which the elevator or merchandiser received official...period may be extended if the elevator owner or operator, or merchandiser...Management and Budget under control number 0580-0011)...

2012-01-01

381

7 CFR 800.25 - Required elevator and merchandising records.  

Code of Federal Regulations, 2011 CFR

...State that owns or operates an elevator and every merchandiser...lots of grain for which the elevator or merchandiser received official...period may be extended if the elevator owner or operator, or merchandiser...Management and Budget under control number 0580-0011)...

2011-01-01

382

7 CFR 800.25 - Required elevator and merchandising records.  

Code of Federal Regulations, 2014 CFR

...State that owns or operates an elevator and every merchandiser...lots of grain for which the elevator or merchandiser received official...period may be extended if the elevator owner or operator, or merchandiser...Management and Budget under control number 0580-0011)...

2014-01-01

383

7 CFR 800.25 - Required elevator and merchandising records.  

Code of Federal Regulations, 2013 CFR

...State that owns or operates an elevator and every merchandiser...lots of grain for which the elevator or merchandiser received official...period may be extended if the elevator owner or operator, or merchandiser...Management and Budget under control number 0580-0011)...

2013-01-01

384

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.  

Code of Federal Regulations, 2011 CFR

...penetration for a stairway or elevator exceeds one deck, the integrity...penetration for a stairway or elevator involves only one deck, the...bulkheads of the same fire control boundary rating as the deck...in the way of stairways or elevators need not be assured....

2011-10-01

385

7 CFR 800.25 - Required elevator and merchandising records.  

Code of Federal Regulations, 2010 CFR

...State that owns or operates an elevator and every merchandiser...lots of grain for which the elevator or merchandiser received official...period may be extended if the elevator owner or operator, or merchandiser...Management and Budget under control number 0580-0011)...

2010-01-01

386

72. View of elevated Mainline structure looking North ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

72. View of elevated Mainline structure - looking North - along Washington Street at juncture of Section F-5 and Section F-6 (the concrete enclosed portion of structure). Remaining stub of the former incline that led down to the Arborway storage yards is at the right. - Boston Elevated Railway, Elevated Mainline, Washington Street, Boston, Suffolk County, MA

387

Evapotranspiration along an elevation gradient in California's Sierra Nevada  

E-print Network

length increased from 405 m to 1160 m, and that mid-elevation sites were photosynthetically active year-length remains constant (or decreases) with increasing elevation), with the main discrepancy a result of the year-length on gas exchange. The climatic conditions at mid-elevation allow year-

Goulden, M. L.; Anderson, R. G.; Bales, R. C.; Kelly, A. E.; Meadows, M.; Winston, G. C.

2012-01-01

388

Mapping Surface Elevation Changes of Outlet Glaciers Using Combined Laser Altimeter and Digital Elevation Model Data  

NASA Astrophysics Data System (ADS)

Ice surface elevation measurements from satellite and airborne laser altimeters have a relatively low error, but are spatially limited to satellite orbits and flight paths. Photogrammetric Digital Elevation Models (DEMs) have a larger error, but provide a continuous surface. We combine the complementary capabilities of these datasets to construct high-resolution (~100 m) maps of surface elevation and elevation change over rapidly changing outlet glaciers. Such a high resolution is needed to resolve the spatial variability of change over narrow ice streams and shear margins. The basic principle of our method is to constrain the DEM surfaces to the altimeter flight lines where they overlap in space and time, both reducing the registration error in the DEM and filling the gaps between altimeter paths. We use laser altimeter data from ICESat and NASA ATM as well as DEMs from the French SPOT 5 satellite. The observation areas are the Greenland outlet glaciers Jakobshavn Isbrae and Kangerdlugssuaq, and the elevation changes are estimated during the period 2007 - 2008. We register the DEMs to the overlapping altimeter data using a least-squares approach, followed by subtraction and interpolation of the residuals to yield a corrected surface. We test two geostatistical interpolation methods: Kriging and optimal linear estimation. Both methods yield similar results. For Jakobshavn, the terminus region thinned with -35 to -30 m/yr and the flow channel with approximately -20 to -10 m/yr. The remaining surface was approximately unchanged. For Kangerdlugssuaq, the terminus thinned with -20 to -7 m/yr and the flow channel with -15 m/yr. At higher elevations, the surface rose with approximately 10 m/yr. The errors are also similar, 0.3 - 7 m/yr and 0.2 - 4 m/yr, respectively, and their magnitude is largely dependent on altimeter data coverage. This information is crucial for airborne altimeter flight planning as such error maps can be used to estimate the spatial density of flights to minimize uncertainty.

Levinsen, J. F.; Tscherning, C. C.; Howat, I. M.

2011-12-01

389

Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2  

NASA Astrophysics Data System (ADS)

This study focuses on the present-day surface elevation of the Greenland and Antarctic ice sheets. Based on 3 years of CryoSat-2 data acquisition we derived new elevation models (DEMs) as well as elevation change maps and volume change estimates for both ice sheets. Here we present the new DEMs and their corresponding error maps. The accuracy of the derived DEMs for Greenland and Antarctica is similar to those of previous DEMs obtained by satellite-based laser and radar altimeters. Comparisons with ICESat data show that 80% of the CryoSat-2 DEMs have an uncertainty of less than 3 m ± 15 m. The surface elevation change rates between January 2011 and January 2014 are presented for both ice sheets. We compared our results to elevation change rates obtained from ICESat data covering the time period from 2003 to 2009. The comparison reveals that in West Antarctica the volume loss has increased by a factor of 3. It also shows an anomalous thickening in Dronning Maud Land, East Antarctica which represents a known large-scale accumulation event. This anomaly partly compensates for the observed increased volume loss of the Antarctic Peninsula and West Antarctica. For Greenland we find a volume loss increased by a factor of 2.5 compared to the ICESat period with large negative elevation changes concentrated at the west and southeast coasts. The combined volume change of Greenland and Antarctica for the observation period is estimated to be -503 ± 107 km3 yr-1. Greenland contributes nearly 75% to the total volume change with -375 ± 24 km3 yr-1.

Helm, V.; Humbert, A.; Miller, H.

2014-08-01

390

Galileo mission planning for Low Gain Antenna based operations  

Microsoft Academic Search

The Galileo mission operations concept is undergoing substantial redesign, necessitated by the deployment failure of the High Gain Antenna, while the spacecraft is on its way to Jupiter. The new design applies state-of-the-art technology and processes to increase the telemetry rate available through the Low Gain Antenna and to increase the information density of the telemetry. This paper describes the

R. Gershman; K. L. Buxbaum; J. M. Ludwinski; B. G. Paczkowski

1994-01-01

391

GALILEO MISSION PLANNING FOR LOW GAIN ANTENNA BASED OPERATIONS  

Microsoft Academic Search

The Galileo mission operations concept is undergo- ing substantial redesign, necessitated by the deploy- ment failure of the High Gain Antenna, while the spacecraft is on its way to Jupiter. The new design applies state-of-the-art technology and processes to increase the telemetry rate available through the Low Gain Antenna and to increase the information density of the telemetry. This paper

R. Gershman; K. L. Buxbaum; B. G. Paczkowski

392

Continental heat gain in the global climate system Hugo Beltrami  

E-print Network

Continental heat gain in the global climate system Hugo Beltrami Department of Earth Sciences, St the past half-century. However, the heat gain of the lithosphere via a heat flux across the solid surface of the global climate system has yielded estimates of heat content increases within three of the system's major

Smerdon, Jason E.

393

TRADE COSTS AND THE GAINS FROM TRADE IN CROP AGRICULTURE  

E-print Network

TRADE COSTS AND THE GAINS FROM TRADE IN CROP AGRICULTURE JEFFREY J. REIMER AND MAN LI We develop trade, and the elasticity of trade volumes to trade costs. The distribution of the gains from trade the extent by which changes in one country are transmitted to others. Key words: geography, grains, trade

Tullos, Desiree

394

Gantry cranes gain scheduling feedback control with friction compensation  

Microsoft Academic Search

We designed a controller based on gain-scheduling feedback to move a load on a gantry crane from point to point within one oscillation cycle and without inducing large swings. The settling time of the system is taken to be equal to the period of oscillation of the load. This criterion enables calculation of the controller feedback gains for varying load

Hanafy M. Omar; Ali H. Nayfeh

2005-01-01

395

Gain scheduled sensorless control of a synchronous reluctance motor  

Microsoft Academic Search

Presented in this paper is an extension to previous work on observer-based sensorless control of synchronous reluctance motors. The extensions include a systematic observer gain calculation that facilitates the use of gain scheduling to improve the transient response of the observer over a wide speed range and improve the low speed performance of the closed-loop sensorless controller. Laboratory experiments are

Matthew B. Hortman; David G. Taylor

2004-01-01

396

Gain-scheduled reusable launch vehicle attitude controller design  

Microsoft Academic Search

A new kind of gain-scheduled attitude controller for reusable launch vehicle is presented. In this paper, gain-scheduled controller design is finished without considering small perturbation linearization. Simultaneously, coordinated scheduling controller is used to deal with intentionally cross coupling. This framework is applied to the design of coupling between roll, pitch and yaw of reusable launch vehicle with large angles of

Nai-gang Cui; Jiangtao Xu; Rongjun Mu; Pengxin Han

2009-01-01

397

Analysis and design of nonlinear gain-scheduled control systems  

Microsoft Academic Search

Although traditional gain-scheduling is intuitively appealing, its heuristic nature usually introduces limitations into its achievable performance, mainly due to two factors: (1) the introduction of approximation errors in the linearization phase, and (2) the negligence of future transitions between operating points during the design phase. In this dissertation, we consider analysis and design of nonlinear gain-scheduled control systems. Nonlinear control

Kuang-Hsuan Tu

1997-01-01

398

Ethanol Consumption Does Not Promote Weight Gain in Female Mice  

Microsoft Academic Search

Background: The prevalence of obese adult women has increased dramatically in the United States. Individuals consuming alcoholic beverages may obtain as much as 6–10% of their calories from ethanol; consequently, ethanol may contribute to a positive energy balance and weight gain in women consuming ethanol. The objective of these studies is to determine if ethanol consumption affects weight gain or

Rebekah R. Smith; Jina Hong; Alison E. Harvey; Tamara Lewis; Daniel Diaz; Nomelí P. Núñez

2008-01-01

399

Do shareholders of acquiring firms gain from acquisitions?  

Microsoft Academic Search

We examine a sample of 12,023 acquisitions by public firms from 1980 to 2001. Shareholders of these firms lost a total of $218 billion when acquisitions were announced. Though shareholders lose throughout our sample period, losses associated with acquisition announcements after 1997 are dramatic. Small firms gain from acquisitions, so that shareholders of small firms gained $8 billion when acquisitions

Sara B. Moeller; Frederik P. Schlingemann; Rene M. Stulz

2003-01-01

400

Weight Gain during Pregnancy: Importance for Maternal and Child Health  

Microsoft Academic Search

Gestational weight gain is a strong predictor of short- and long-term health outcomes for both childbearing women and their offspring. Epidemiologic studies have found that higher maternal gestational weight gains are associated with abnormalities in maternal prenatal glycemia, hypertensive disorders of pregnancy and delivery complications, along with an increased risk of postpartum weight retention, incident obesity and adverse cardiometabolic sequelae

Sharon J. Herring; Emily Oken

2010-01-01

401

Long-period fiber-grating-based gain equalizers  

Microsoft Academic Search

Long-period fiber gratings are used to flatten the gain spectrum of erbium-doped fiber amplifiers. A broadband amplifier with >0.2-dB gain variation over 30 nm is presented. We also show that a chain of amplifiers can be equalized, leading to a bandwidth enhancement by a factor of 3. {copyright} {ital 1996 Optical Society of America.}

Ashish M. Vengsarkar; J. Renee Pedrazzani; Justin B. Judkins; Paul J. Lemaire; Neal S. Bergano; Carl R. Davidson

1996-01-01

402

Validity of Sudden Gains in Acute Phase Treatment of Depression  

ERIC Educational Resources Information Center

The authors examined the validity of sudden gains identified with T. Z. Tang and R. J. DeRubeis's (1999) method in 2 clinical data sets that involved treatment of major depressive disorder (N=227). Sudden gains replicated among self- and clinician reports of depressive symptoms and predicted better psychosocial functioning at the acute phase…

Vittengl, Jeffrey R.; Clark, Lee Anna; Jarrett, Robin B.

2005-01-01

403

24 CFR 3280.506 - Heat loss/heat gain.  

Code of Federal Regulations, 2012 CFR

...Development 5 2012-04-01 2012-04-01 false Heat loss/heat gain. 3280.506 Section 3280.506 Housing and...SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat...

2012-04-01

404

24 CFR 3280.506 - Heat loss/heat gain.  

Code of Federal Regulations, 2010 CFR

...Development 5 2010-04-01 2010-04-01 false Heat loss/heat gain. 3280.506 Section 3280.506 Housing and...SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat...

2010-04-01

405

24 CFR 3280.506 - Heat loss/heat gain.  

Code of Federal Regulations, 2013 CFR

...Development 5 2013-04-01 2013-04-01 false Heat loss/heat gain. 3280.506 Section 3280.506 Housing and...SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat...

2013-04-01

406

24 CFR 3280.506 - Heat loss/heat gain.  

Code of Federal Regulations, 2011 CFR

...Development 5 2011-04-01 2011-04-01 false Heat loss/heat gain. 3280.506 Section 3280.506 Housing and...SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat...

2011-04-01

407

24 CFR 3280.506 - Heat loss/heat gain.  

Code of Federal Regulations, 2014 CFR

...Development 5 2014-04-01 2014-04-01 false Heat loss/heat gain. 3280.506 Section 3280.506 Housing and...SAFETY STANDARDS Thermal Protection § 3280.506 Heat loss/heat gain. The manufactured home heat...

2014-04-01

408

Missile autopilot design using a gain scheduling technique  

Microsoft Academic Search

A recently developed framework for gain scheduled control system synthesis is applied to a missile autopilot design problem. In contrast to previous approaches, low order linear autopilots designed at discrete operating points using classical control techniques are gain scheduled. Also, mach number, modeled as a measured, time-varying exogenous signal, is viewed as a disturbance to be rejected in the linear

David P. White; Jason G. Wozniak; Douglas A. Lawrence

1994-01-01

409

Finding Optimal Gains In Linear-Quadratic Control Problems  

NASA Technical Reports Server (NTRS)

Analytical method based on Volterra factorization leads to new approximations for optimal control gains in finite-time linear-quadratic control problem of system having infinite number of dimensions. Circumvents need to analyze and solve Riccati equations and provides more transparent connection between dynamics of system and optimal gain.

Milman, Mark H.; Scheid, Robert E., Jr.

1990-01-01

410

Hybrid ElectricOIL Discharge, Gain, and Power Enhancements  

E-print Network

(ElectricOIL) system that significantly increased the discharge performance, supersonic cavity gain1 Hybrid ElectricOIL Discharge, Gain, and Power Enhancements G. F. Benavides,1,5 A. D. Palla,1 D. M iodine at 1315 nm was pumped by the production of O2(a1 ) in a radio-frequency discharge in an O2/He

Carroll, David L.

411

Focal-Plane Analysis For Calculating Antenna Gain  

NASA Technical Reports Server (NTRS)

Improved method devised for calculating gain of antenna system comprising main reflector and array of feed elements. Method involves much less computation; important advantage when necessary to compute gains repeatedly, with slight variations in design at each iteration, in effort to find optimum design.

Cramer, Paul W.; Imbriale, William A.; Rengarajan, Sembiam R.

1996-01-01

412

The Causes of and Gains from Intertemporal Trade  

ERIC Educational Resources Information Center

The authors show how the causes of and the gains from current account imbalances can be integrated into undergraduate economics courses using the same pedagogical tools that are used to explain comparative advantage and the gains from trade. A nonzero current account provides a mechanism for intertemporal trade, and a country has a comparative…

Craighead, William D.; Miller, Norman C.

2010-01-01

413

Slow-light-enhanced gain in active photonic crystal waveguides.  

PubMed

Passive photonic crystals have been shown to exhibit a multitude of interesting phenomena, including slow-light propagation in line-defect waveguides. It was suggested that by incorporating an active material in the waveguide, slow light could be used to enhance the effective gain of the material, which would have interesting application prospects, for example enabling ultra-compact optical amplifiers for integration in photonic chips. Here we experimentally investigate the gain of a photonic crystal membrane structure with embedded quantum wells. We find that by solely changing the photonic crystal structural parameters, the maximum value of the gain coefficient can be increased compared with a ridge waveguide structure and at the same time the spectral position of the peak gain be controlled. The experimental results are in qualitative agreement with theory and show that gain values similar to those realized in state-of-the-art semiconductor optical amplifiers should be attainable in compact photonic integrated amplifiers. PMID:25266779

Ek, Sara; Lunnemann, Per; Chen, Yaohui; Semenova, Elizaveta; Yvind, Kresten; Mork, Jesper

2014-01-01

414

Adaptive gain and filtering circuit for a sound reproduction system  

NASA Technical Reports Server (NTRS)

Adaptive compressive gain and level dependent spectral shaping circuitry for a hearing aid include a microphone to produce an input signal and a plurality of channels connected to a common circuit output. Each channel has a preset frequency response. Each channel includes a filter with a preset frequency response to receive the input signal and to produce a filtered signal, a channel amplifier to amplify the filtered signal to produce a channel output signal, a threshold register to establish a channel threshold level, and a gain circuit. The gain circuit increases the gain of the channel amplifier when the channel output signal falls below the channel threshold level and decreases the gain of the channel amplifier when the channel output signal rises above the channel threshold level. A transducer produces sound in response to the signal passed by the common circuit output.

Engebretson, A. Maynard (Inventor); O'Connell, Michael P. (Inventor)

1998-01-01

415

Elevations and distances in the United States  

USGS Publications Warehouse

The information in this booklet was compiled to answer inquiries received by the U.S. Geological Survey from students; teachers; writers; editors; publishers of encyclopedias, almanacs, and other reference books; and people in many other fields of work. The elevations of features and distances between points in the United States were determined from surveys and topographic maps of the U.S. Geological Survey or obtained from other sources. In most cases, the elevations were determined from surveys and from 1:24,000- and 1:25,000-scale, 7.5-minute topographic quadrangle maps. In Alaska, information was taken from 1:63,360-scale, 15-minute topographic quadrangle maps. In a few cases, data were obtained from older, 1:62,500-scale, 15-minute maps; these maps are being replaced with larger-scale 7.5-minute coverage. Further information about U.S. Geological Survey products can be obtained from: U.S. Geological Survey, Earth Science Information Center, 507 National Center, Reston, VA 22092 or phone 703-860-6045.

U.S. Geological Survey

1991-01-01

416

Relationship Between Optimal Gain and Coherence Zone in Flight Simulation  

NASA Technical Reports Server (NTRS)

In motion simulation the inertial information generated by the motion platform is most of the times different from the visual information in the simulator displays. This occurs due to the physical limits of the motion platform. However, for small motions that are within the physical limits of the motion platform, one-to-one motion, i.e. visual information equal to inertial information, is possible. It has been shown in previous studies that one-to-one motion is often judged as too strong, causing researchers to lower the inertial amplitude. When trying to measure the optimal inertial gain for a visual amplitude, we found a zone of optimal gains instead of a single value. Such result seems related with the coherence zones that have been measured in flight simulation studies. However, the optimal gain results were never directly related with the coherence zones. In this study we investigated whether the optimal gain measurements are the same as the coherence zone measurements. We also try to infer if the results obtained from the two measurements can be used to differentiate between simulators with different configurations. An experiment was conducted at the NASA Langley Research Center which used both the Cockpit Motion Facility and the Visual Motion Simulator. The results show that the inertial gains obtained with the optimal gain are different than the ones obtained with the coherence zone measurements. The optimal gain is within the coherence zone.The point of mean optimal gain was lower and further away from the one-to-one line than the point of mean coherence. The zone width obtained for the coherence zone measurements was dependent on the visual amplitude and frequency. For the optimal gain, the zone width remained constant when the visual amplitude and frequency were varied. We found no effect of the simulator configuration in both the coherence zone and optimal gain measurements.

Gracio, Bruno Jorge Correia; Pais, Ana Rita Valente; vanPaassen, M. M.; Mulder, Max; Kely, Lon C.; Houck, Jacob A.

2011-01-01

417

Quantitative characterization and elevation estimation of Lake Lahontan shoreline terraces from high-resolution digital elevation models  

Microsoft Academic Search

The precision with which the elevation of a feature, such as a terrace, can be measured depends on the characterization of the noise contaminating the measurement. A method for identification and extraction of terrace feature elevations is presented and the topographic noise, due to erosion, as well as measurement error, is quantified. High-resolution digital elevation models (DEM) are acquired at

Jennifer L. Hare; John F. Ferguson; Carlos L. V. Aiken; John S. Oldow

2001-01-01

418

Quantitative characterization and elevation estimation of Lake Lahontan shoreline terraces from high-resolution digital elevation models  

Microsoft Academic Search

The precision with which the elevation of a feature, such as a terrace, can be measured depends on the characterization of the noise contaminating the measurement. A method for identification and extraction of terrace feature elevations is presented and the topographic noise, due to erosion, as well as measurement error, is quantified. High- resolution digital elevation models (DEM) are acquired

Jennifer L. Hare; John F. Ferguson; Carlos L. V. Aiken; John S. Oldow

2001-01-01

419

Bergmann's Rule rules body size in an ectotherm: heat conservation in a lizard along a 2200-metre elevational gradient.  

PubMed

Bergmann's Rule predicts larger body sizes in colder habitats, increasing organisms' ability to conserve heat. Originally formulated for endotherms, it is controversial whether Bergmann's Rule may be applicable to ectotherms, given that larger ectotherms show diminished capacity for heating up. We predict that Bergmann's Rule will be applicable to ectotherms when the benefits of a higher conservation of heat due to a larger body size overcompensate for decreased capacity to heating up. We test this hypothesis in the lizard Psammodromus algirus, which shows increased body size with elevation in Sierra Nevada (SE Spain). We measured heating and cooling rates of lizards from different elevations (from 300 to 2500 m above sea level) under controlled conditions. We found no significant differences in the heating rate along an elevational gradient. However, the cooling rate diminished with elevation and body size: highland lizards, with larger masses, have a higher thermal inertia for cooling, which allows them to maintain heat for more time and keep a high body temperature despite the lower thermal availability. Consequently, the net gaining of heat increased with elevation and body size. This study highlights that the heat conservation mechanism for explaining Bergmann's Rule works and is applicable to ectotherms, depending on the thermal benefits and costs associated with larger body sizes. PMID:25387908

Zamora-Camacho, F J; Reguera, S; Moreno-Rueda, G

2014-12-01

420

Gaining Access to Hidden Populations: Strategies for Gaining Cooperation of Drug Sellers\\/Dealers and Their Families in Ethnographic Research  

Microsoft Academic Search

This article examines strategies for gaining the cooperation of drug sellers and their families in order to conduct ethnographic research. The strategies were developed during an eight year study of drug dealers in New York City. A key element in gaining the ability to talk with and observe drug dealers and their family members was the availability of funds to

Eloise Dunlap; Bruce D. Johnson

1998-01-01

421

Additive effects of simulated climate changes, elevated CO2, and nitrogen deposition on grassland diversity  

PubMed Central

Biodiversity responses to ongoing climate and atmospheric changes will affect both ecosystem processes and the delivery of ecosystem goods and services. Combined effects of co-occurring global changes on diversity, however, are poorly understood. We examined plant diversity responses in a California annual grassland to manipulations of four global environmental changes, singly and in combination: elevated CO2, warming, precipitation, and nitrogen deposition. After 3 years, elevated CO2 and nitrogen deposition each reduced plant diversity, whereas elevated precipitation increased it and warming had no significant effect. Diversity responses to both single and combined global change treatments were driven overwhelmingly by gains and losses of forb species, which make up most of the native plant diversity in California grasslands. Diversity responses across treatments also showed no consistent relationship to net primary production responses, illustrating that the diversity effects of these environmental changes could not be explained simply by changes in productivity. In two- to four-way combinations, simulated global changes did not interact in any of their effects on diversity. Our results show that climate and atmospheric changes can rapidly alter biological diversity, with combined effects that, at least in some settings, are simple, additive combinations of single-factor effects. PMID:12810960

Zavaleta, Erika S.; Shaw, M. Rebecca; Chiariello, Nona R.; Mooney, Harold A.; Field, Christopher B.

2003-01-01

422

Nitrogen saturation and soil N availability in a high-elevation spruce and fir forest  

SciTech Connect

A field study was conducted during the summer of 1995 to gain abetter understanding of the causes of nitrate (NO{sub 3}-N) leaching and ongoing changes in soil nitrogen (N) availability in high-elevation (1524-2000 m) spruce (Picea rubens) and fir (Abies fraseri) forests of the Great Smoky Mountains National Park, Tennessee and North Carolina, U.S.A. Indicators of soil N availability (total soil N concentrations, extractable NH{sub 4}-N, extractable NO{sub 3}-N, and C/N ratios) were measured in Oa and A horizons at 33 study plots. Dynamic measures included potential net soil N mineralization determined in 12-week aerobic laboratory incubations at 22 C. Potential net nitrification in the A horizon was correlated (r = + 0.83, P < 0.001) with total soil n concentrations. mostmeasures of soil n availability did not exhibit significanttrends with elevation, but there were topographic differences. Potential net soil N mineralization and net nitrification in the A horizon were higher in coves than on ridges. Relative amounts of particulate and organomineral soil organic matter influenced potential net N mineralization and nitrification in the A horizon. Calculations indicate that soil N availability and NO{sub 3}-N leaching in high-elevation spruce and fir forests of the Great Smoky Mountains National Park will increase in response to regional warming.

Garten Jr, Charles T [ORNL

2000-06-01

423

Dead wood biomass and turnover time, measured by radiocarbon, along a subalpine elevation gradient.  

PubMed

Dead wood biomass can be a substantial fraction of stored carbon in forest ecosystems, and coarse woody debris (CWD) decay rates may be sensitive to climate warming. We used an elevation gradient in Colorado Rocky Mountain subalpine forest to examine climate and species effects on dead wood biomass, and on CWD decay rate. Using a new radiocarbon approach, we determined that the turnover time of lodgepole pine CWD (340+/-130 years) was roughly half as long in a site with 2.5-3 degrees C warmer air temperature, as that of pine (630+/-400 years) or Engelmann spruce CWD (800+/-960 and 650+/-410 years) in cooler sites. Across all sites and both species, CWD age ranged from 2 to 600 years, and turnover time was 580+/-180 years. Total standing and fallen dead wood biomass ranged from 4.7+/-0.2 to 54+/-1 Mg ha(-1), and from 2.8 to 60% of aboveground live tree biomass. Dead wood biomass increased 75 kg ha(-1) per meter gain in elevation and decreased 13 Mg ha(-1) for every degree C increase in mean air temperature. Differences in biomass and decay rates along the elevation gradient suggest that climate warming will lead to a loss of dead wood carbon from subalpine forest. PMID:15338416

Kueppers, Lara M; Southon, John; Baer, Paul; Harte, John

2004-12-01

424

Compartment-specific transcriptomics in a reef-building coral exposed to elevated temperatures  

PubMed Central

Although rising ocean temperatures threaten scleractinian corals and the reefs they construct, certain reef corals can acclimate to elevated temperatures to which they are rarely exposed in situ. Specimens of the model Indo-Pacific reef coral Pocillopora damicornis collected from upwelling reefs of Southern Taiwan were previously found to have survived a 36-week exposure to 30°C, a temperature they encounter infrequently and one that can elicit the breakdown of the coral–dinoflagellate (genus Symbiodinium) endosymbiosis in many corals of the Pacific Ocean. To gain insight into the subcellular pathways utilized by both the coral hosts and their mutualistic Symbiodinium populations to acclimate to this temperature, mRNAs from both control (27°C) and high (30°C)-temperature samples were sequenced on an Illumina platform and assembled into a 236 435-contig transcriptome. These P. damicornis specimens were found to be ?60% anthozoan and 40% microbe (Symbiodinium, other eukaryotic microbes, and bacteria), from an mRNA-perspective. Furthermore, a significantly higher proportion of genes from the Symbiodinium compartment were differentially expressed after two weeks of exposure. Specifically, at elevated temperatures, Symbiodinium populations residing within the coral gastrodermal tissues were more likely to up-regulate the expression of genes encoding proteins involved in metabolism than their coral hosts. Collectively, these transcriptome-scale data suggest that the two members of this endosymbiosis have distinct strategies for acclimating to elevated temperatures that are expected to characterize many of Earth's coral reefs in the coming decades. PMID:25354956

Mayfield, Anderson B; Wang, Yu-Bin; Chen, Chii-Shiarng; Lin, Chung-Yen; Chen, Shu-Hwa

2014-01-01

425

Carbon balance, partitioning and photosynthetic acclimation in fruit-bearing grapevine (Vitis vinifera L. cv. Tempranillo) grown under simulated climate change (elevated CO2, elevated temperature and moderate drought) scenarios in temperature gradient greenhouses.  

PubMed

Although plant performance under elevated CO2 has been extensively studied in the past little is known about photosynthetic performance changing simultaneously CO2, water availability and temperature conditions. Moreover, despite of its relevancy in crop responsiveness to elevated CO2 conditions, plant level C balance is a topic that, comparatively, has received little attention. In order to test responsiveness of grapevine photosynthetic apparatus to predicted climate change conditions, grapevine (Vitis vinifera L. cv. Tempranillo) fruit-bearing cuttings were exposed to different CO2 (elevated, 700ppm vs. ambient, ca. 400ppm), temperature (ambient vs. elevated, ambient +4°C) and irrigation levels (partial vs. full irrigation). Carbon balance was followed monitoring net photosynthesis (AN, C gain), respiration (RD) and photorespiration (RL) (C losses). Modification of environment (13)C isotopic composition (?(13)C) under elevated CO2 (from -10.30 to -24.93‰) enabled the further characterization of C partitioning into roots, cuttings, shoots, petioles, leaves, rachides and berries. Irrespective of irrigation level and temperature, exposure to elevated CO2 induced photosynthetic acclimation of plants. C/N imbalance reflected the inability of plants grown at 700ppm CO2 to develop strong C sinks. Partitioning of labeled C to storage organs (main stem and roots) did not avoid accumulation of labeled photoassimilates in leaves, affecting negatively Rubisco carboxylation activity. The study also revealed that, after 20 days of treatment, no oxidative damage to chlorophylls or carotenoids was observed, suggesting a protective role of CO2 either at current or elevated temperatures against the adverse effect of water stress. PMID:25462972

Salazar-Parra, Carolina; Aranjuelo, Iker; Pascual, Inmaculada; Erice, Gorka; Sanz-Sáez, Alvaro; Aguirreolea, Jone; Sánchez-Díaz, Manuel; Irigoyen, Juan José; Araus, José Luis; Morales, Fermín

2015-02-01

426

Extensive intron gain in the ancestor of placental mammals  

PubMed Central

Background Genome-wide studies of intron dynamics in mammalian orthologous genes have found convincing evidence for loss of introns but very little for intron turnover. Similarly, large-scale analysis of intron dynamics in a few vertebrate genomes has identified only intron losses and no gains, indicating that intron gain is an extremely rare event in vertebrate evolution. These studies suggest that the intron-rich genomes of vertebrates do not allow intron gain. The aim of this study was to search for evidence of de novo intron gain in domesticated genes from an analysis of their exon/intron structures. Results A phylogenomic approach has been used to analyse all domesticated genes in mammals and chordates that originated from the coding parts of transposable elements. Gain of introns in domesticated genes has been reconstructed on well established mammalian, vertebrate and chordate phylogenies, and examined as to where and when the gain events occurred. The locations, sizes and amounts of de novo introns gained in the domesticated genes during the evolution of mammals and chordates has been analyzed. A significant amount of intron gain was found only in domesticated genes of placental mammals, where more than 70 cases were identified. De novo gained introns show clear positional bias, since they are distributed mainly in 5' UTR and coding regions, while 3' UTR introns are very rare. In the coding regions of some domesticated genes up to 8 de novo gained introns have been found. Intron densities in Eutheria-specific domesticated genes and in older domesticated genes that originated early in vertebrates are lower than those for normal mammalian and vertebrate genes. Surprisingly, the majority of intron gains have occurred in the ancestor of placentals. Conclusions This study provides the first evidence for numerous intron gains in the ancestor of placental mammals and demonstrates that adequate taxon sampling is crucial for reconstructing intron evolution. The findings of this comprehensive study slightly challenge the current view on the evolutionary stasis in intron dynamics during the last 100 - 200 My. Domesticated genes could constitute an excellent system on which to analyse the mechanisms of intron gain in placental mammals. Reviewers: this article was reviewed by Dan Graur, Eugene V. Koonin and Jürgen Brosius. PMID:22112745

2011-01-01

427

Evaluation of Experimental Data from the GAINS Balloon GPS Surface Reflection Instrument  

NASA Technical Reports Server (NTRS)

The GPS Surface Reflection Instrument was integrated as an experiment on the GAINS (Global Airocean IN-situ System) 48-hour balloon mission flown in September 2001. The data collected by similar instruments in the past has been used to measure sea state from which ocean surface winds can be accurately estimated. The GPS signal has also been shown to be reflected from wetland areas and even from subsurface moisture. The current version of the instrument has been redesigned to be more compact, use less power, and withstand a greater variation in environmental conditions than previous versions. This instrument has also incorporated a new data collection mode to track 5 direct satellites (providing a continuous navigation solution) and multiplex the remaining 7 channels to track the reflected signal of the satellite tracked in channel 0. The new software mode has been shown to increase the signal to noise ratio of the collected data and enhance the science return of the instrument. During the 48-hour flight over the Northwest US, the instrument will measure surface reflections that can be detected over the balloon's ground track. Since ground surface elevations in this area vary widely from the WGS-84 ellipsoid altitude, the instrument software has been modified to incorporate a surface altitude correction based on USGS 30-minute Digital Elevation Models. Information presented will include facts about instrument design goals, data collection methodologies and algorithms, and results of the science data analyses for the 48-hour mission.

Gance, George G.; Johnson, Thomas A.

2004-01-01

428

Comparative Study of Gain Mechanisms in GaN Epilayers and GaN/AlGaN Separate Confinement Heterostructures  

NASA Astrophysics Data System (ADS)

We report the results of an experimental study on near-threshold gain mechanisms in optically pumped GaN epilayers and GaN/AlGaN separate confinement heterostructures (SCHs) in the temperature range of 10 to 300 K and identify critical issues necessary for the development of near- and deep-UV laser diodes. We show that the near-threshold gain mechanism in GaN epilayers is inelastic exciton-exciton scattering for temperatures below ~150 K, whereas at elevated temperatures an electron-hole plasma is the dominant gain mechanism. The Mott density in GaN (density at which excitons dissociate) was estimated to be 1.1× 10^18 cm-3. By improving carrier and optical confinement we were able to extend the exciton-exciton scattering gain mechanism up to room temperature in GaN/AlGaN SCHs. A remarkably low lasing threshold (carrier density substantially below the Mott density) was achieved in SCH heterostructures over the temperature range of 10 to 300 K. The implications of this study on the development of UV laser diodes will be discussed. This work was supported by AFOSR and BMDO.

Bidnyk, Sergiy; Biu Lam, Jack; Little, Brian; Gainer, Gordon; Song, Jin Joo

2000-03-01

429

Gain-switched pulses from InGaAs ridge-quantum-well lasers limited by intrinsic dynamical gain suppression.  

PubMed

Gain-switched pulses of InGaAs double-quantum-well lasers fabricated from identical epitaxial laser wafers were measured under both current injection and optical pumping conditions. The shortest output pulse widths were nearly identical (about 40 ps) both for current injection and optical pumping; this result attributed the dominant pulse-width limitation factor to the intrinsic gain properties of the lasers. We quantitatively compared the experimental results with theoretical calculations based on rate equations incorporating gain nonlinearities. Close consistency between the experimental data and the calculations was obtained only when we assumed a dynamically suppressed gain value deviated from the steady-state gain value supported by standard microscopic theories. PMID:23546139

Chen, Shaoqiang; Yoshita, Masahiro; Ito, Takashi; Mochizuki, Toshimitsu; Akiyama, Hidefumi; Yokoyama, Hiroyuki

2013-03-25

430

Traction sheave elevator, hoisting unit and machine space  

DOEpatents

Traction sheave elevator consisting of an elevator car moving along elevator guide rails, a counterweight moving along counterweight guide rails, a set of hoisting ropes (3) on which the elevator car and counterweight are suspended, and a drive machine unit (6) driving a traction sheave (7) acting on the hoisting ropes (3) and placed in the elevator shaft. The drive machine unit (6) is of a flat construction. A wall of the elevator shaft is provided with a machine space with its open side facing towards the shaft, the essential parts of the drive machine unit (6) being placed in the space. The hoisting unit (9) of the traction sheave elevator consists of a substantially discoidal drive machine unit (6) and an instrument panel (8) mounted on the frame (20) of the hoisting unit.

Hakala, Harri (Hyvinkaa, FI); Mustalahti, Jorma (Hyvinkaa, FI); Aulanko, Esko (Kerava, FI)

2000-01-01

431

Effects of Fully Open-Air [CO2] Elevation on Leaf Photosynthesis and Ultrastructure of Isatis indigotica Fort  

PubMed Central

Traditional Chinese medicine relies heavily on herbs, yet there is no information on how these herb plants would respond to climate change. In order to gain insight into such response, we studied the effect of elevated [CO2] on Isatis indigotica Fort, one of the most popular Chinese herb plants. The changes in leaf photosynthesis, chlorophyll fluorescence, leaf ultrastructure and biomass yield in response to elevated [CO2] (550±19 µmol mol–1) were determined at the Free-Air Carbon dioxide Enrichment (FACE) experimental facility in North China. Photosynthetic ability of I. indigotica was improved under elevated [CO2]. Elevated [CO2] increased net photosynthetic rate (PN), water use efficiency (WUE) and maximum rate of electron transport (Jmax) of upper most fully-expended leaves, but not stomatal conductance (gs), transpiration ratio (Tr) and maximum velocity of carboxylation (Vc,max). Elevated [CO2] significantly increased leaf intrinsic efficiency of PSII (Fv’/Fm’) and quantum yield of PSII(?PSII), but decreased leaf non-photochemical quenching (NPQ), and did not affect leaf proportion of open PSII reaction centers (qP) and maximum quantum efficiency of PSII (Fv/Fm). The structural chloroplast membrane, grana layer and stroma thylakoid membranes were intact under elevated [CO2], though more starch grains were accumulated within the chloroplasts than that of under ambient [CO2]. While the yield of I. indigotica was higher due to the improved photosynthesis under elevated [CO2], the content of adenosine, one of the functional ingredients in indigowoad root was not affected. PMID:24058596

Hao, Xingyu; Li, Ping; Feng, Yongxiang; Han, Xue; Gao, Ji; Lin, Erda; Han, Yuanhuai

2013-01-01

432

Field Dependent Dopant Deactivation in Bipolar Devices at Elevated irradiation Temperatures  

SciTech Connect

Metal-oxide-silicon capacitors fabricated in a bi-polar process were examined for densities of oxide trapped charge, interface traps and deactivated substrate acceptors following high-dose-rate irradiation at 100 C. Acceptor neutralization near the Si surface occurs most efficiently for small irradiation biases in depletion. The bias dependence is consistent with compensation and passivation mechanisms involving the drift of H{sup +} ions in the oxide and Si layers and the availability of holes in the Si depletion region. Capacitor data from unbiased irradiations were used to simulate the impact of acceptor neutralization on the current gain of an npn bipolar transistor. Neutralized acceptors near the base surface enhance current gain degradation associated with radiation-induced oxide trapped charge and interface traps by increasing base recombination. The additional recombination results from the convergence of carrier concentrations in the base and increased sensitivity of the base to oxide trapped charge. The enhanced gain degradation is moderated by increased electron injection from the emitter. These results suggest that acceptor neutralization may enhance radiation-induced degradation of linear circuits at elevated temperatures.

WITCZAK,STEVEN C.; LACOE,RONALD C.; SHANEYFELT,MARTY R.; MAYER,DONALD C.; SCHWANK,JAMES R.; WINOKUR,PETER S.

2000-08-15

433

Low Gestational Weight Gain Skews Human Sex Ratios towards Females  

PubMed Central

Background Human males are more vulnerable to adverse conditions than females starting early in gestation and continuing throughout life, and previous studies show that severe food restriction can influence the sex ratios of human births. It remains unclear, however, whether subtle differences in caloric intake during gestation alter survival of fetuses in a sex-specific way. I hypothesized that the ratio of male to female babies born should vary with the amount of weight gained during gestation. I predicted that women who gain low amounts of weight during gestation should produce significantly more females, and that, if gestational weight gain directly influences sex ratios, fetal losses would be more likely to be male when women gain inadequate amounts of weight during pregnancy. Methods I analyzed data collected from over 68 million births over 23 years to test for a relationship between gestational weight gain and natal sex ratios, as well as between gestational weight gain and sex ratios of fetal deaths at five gestational ages. Results Gestational weight gain and the proportion of male births were positively correlated; a lower proportion of males was produced by women who gained less weight and this strong pattern was exhibited in four human races. Further, sex ratios of fetal losses at 6 months of gestation were significantly male-biased when mothers had gained low amounts of weight during pregnancy, suggesting that low caloric intake during early fetal development can stimulate the loss of male fetuses. Conclusion My data indicate that human sex ratios change in response to resource availability via sex-specific fetal loss, and that a pivotal time for influences on male survival is early in fetal development, at 6 months of gestation. PMID:25493647

Navara, Kristen J.

2014-01-01

434

Optical properties of diamond at elevated temperatures  

SciTech Connect

The unique multispectral transparency properties of diamond, combined with its chemical inertness, hardness, and mechanical strength, enable a variety of optical applications requiring infrared transparency in aggressive environments. Knowledge of the optical properties of diamond at elevated temperatures enables the use of Fizeau interferometry as an in situ, non-contact probe of temperature, for homoepitaxial diamond growth studies, for example, and may be useful for other applications as well. The temperature dependence of the index of refraction of type IIa natural diamond was determined by Fizeau interferometry using a HeNe laser. Subtracting the contribution of thermal expansion to the optical path length, the logarithmic temperature derivative of the refractive index, 1/n dn/dT, is found to rise from 4 x 10{sup -6} at room temperature to 2.0 x 10{sup -5} at 1200 {degrees}C at a wavelength of 633 nm.

Rawles, R.E. [Rice Univ., Houston, TX (United States); D`Evelyn, M.P. [Rensselaer Polytechnic Institute, Troy, NY (United States)

1995-12-31

435

Minimizing Uncertainty in Coastal Digital Elevation Models  

NASA Astrophysics Data System (ADS)

Digital elevation models (DEMs) have inherent uncertainties in their values that impact the accuracies of coastal inundation studies that utilize them. Sources of DEM uncertainty include: uncertainty of source data, gridding interpolation to fill data gaps, and morphologic change after data collection. These uncertainties are propagated into modeling results such that the modeling of coastal inundation cannot be more accurate than the source DEMs they rely upon. We describe some of the major challenges in building coastal DEMs--those that integrate bathymetry and topography at the coast--and how to recognize errors and minimize model uncertainties. We also discuss procedures for building DEMs, and the efforts of NOAA and USGS to develop high-resolution DEMs of coastal areas impacted by Hurricane Sandy in October 2012.

Eakins, B.; Danielson, J.; McLean, S. J.

2013-12-01

436

Airborne mycotoxins in dust from grain elevators.  

PubMed

Workers in grain elevators are exposed to grain dust and may therefore have an increased risk of inhalatory contact with mycotoxins. To study the mycotoxin burden of such environments, settled grain dust samples (n=35) were collected from several locations of a total of 13 grain elevators in Germany, and analysed for ochratoxin A (OTA, detection limit 0.01 ng/g), deoxynivalenol (DON, detection limit 15 ng/g), and zearalenone (ZEA, detection limit 6 ng/g), respectively. Cytotoxicity of these samples was assessed by a MTT bioassay with a swine kidney target cell line. Additionally, the airborne dust concentration of these locations was determined. Nearly all settled dust samples contained OTA (96%), DON (100%), and ZEA (100%) with median concentrations of 0.4 ng/g, 416 ng/g, and 126 ng/g, respectively. Cytotoxic effects in varying degrees from weakly to highly toxic were caused by crude extracts of 86% of the dust samples. However, cytotoxicity did not correlate with mycotoxin levels in these samples and thus indicated the presence of cytotoxic compounds of unknown origin. Based on the mycotoxin findings in settled dust samples and the airborne dust concentrations, the average airborne mycotoxin concentrations were estimated to be 0.002 ng/m(3) (OTA), 2 ng/m(3) (DON), and 1 ng/m(3) (ZEA), respectively. The relevance of these findings for occupational health was assessed by comparison with WHO recommendations for the maximum tolerable daily (oral) intake (TDI). Even in a worst case scenario, the calculated inhalatory intake was far below the TDI values. However, considering the uncertainties resulting from different exposure pathways, namely oral ingestion versus inhalation, further research should primarily address the problem of how adequate assessment criteria for airborne exposure to mycotoxins could be established. PMID:23605914

Mayer, S; Curtui, V; Usleber, E; Gareis, M

2007-06-01

437

Procalcitonin elevation suggests a septic source.  

PubMed

Procalcitonin is used as a marker for sepsis but there is little known about the correlation of the procalcitonin elevation with the causative organism in sepsis. All patients aged 18 to 80 years who were admitted to the surgery service from June 2010 to May 2012 and who had a procalcitonin drawn were evaluated. Culture data were reviewed to determine the causative organism. Infections analyzed included pneumonia, urinary tract infection (UTI), bloodstream infection, and Clostridium difficile. Other parameters assessed included reason for admission, body mass index, pressor use, antibiotic duration, and disposition. Two hundred thirty-two patient records were reviewed. Patients without a known infection/source of sepsis had a mean procalcitonin of 3.95. Those with pneumonia had a procalcitonin of 20.59 (P = 0.03). Those with a UTI had a mean procalcitonin of 66.84 (P = 0.0005). Patients with a bloodstream infection had a mean procalcitonin of 33.30 (P = 0.003). Those with C. difficile had a procalcitonin of 47.20 (P = 0.004). When broken down by causative organisms, those with Gram-positive sepsis had a procalcitonin of 23.10 (P = 0.02) compared with those with Gram-negative sepsis at 32.75 (P = 0.02). Those with fungal infections had a procalcitonin of 42.90 (P = 0.001). These data suggest that procalcitonin elevation can help guide treatment by indicating likely causative organism and infection type. These data may provide a good marker for initiation of antifungal therapy. PMID:25197879

Friend, Kara E; Burgess, Jessica N; Britt, Rebecca C; Collins, Jay N; Weireter, Leonard N; Novosel, Timothy J; Britt, L D

2014-09-01

438

Elevated PTH After Parathyroidectomy Delays Symptom Improvement  

PubMed Central

Background Curative parathyroidectomy for primary hyperparathyroidism (PHPT) resolves various nonspecific symptoms related to the disease. Between 8 to 40% of patients with normocalcemia after parathyroidectomy have persistently elevated parathyroid hormone levels (ePTH) at follow-up. We investigated whether ePTH in the early post-operative period was associated with the timing of symptom improvement. Materials and Methods This prospective study included adult patients with PHPT who underwent curative parathyroidectomy from November 2011 to September 2012. Biochemical testing 2 weeks post-operatively identified ePTH (defined as PTH > 72 pg/mL) versus normal PTH (nPTH). A questionnaire administered pre- and post-operatively at 6 weeks and 6 months asked patients to rate the frequency of 18 symptoms of PHPT on a 5-point Likert scale. Student’s T-tests were used to compare pre- to post-operative changes in scores for individual symptoms. Results Of 194 patients that underwent parathyroidectomy, 129 (66%) participated in the study. Pre-operatively, all patients were symptomatic, with a mean of 13±4 symptoms. Two weeks post-operatively, 20 patients (16%) had ePTH. The percentage of patients with post-operative improvement for individual symptoms was compared between groups. At the early time point (6 weeks), the ePTH group showed less improvement in 14 of 18 symptoms. This difference reached statistical significance for four symptoms: anxiety, constipation, thirst, and polyuria. By the 6 month time point, these differences had resolved and symptom improvement was similar between groups. Conclusions Elevated PTH after curative parathyroidectomy may result in a delay in symptom improvement 6 weeks post-operatively, however, this difference resolves by 6 months. PMID:24685332

Pathak, Priya R.; Holden, Sara E.; Schaefer, Sarah C.; Leverson, Glen; Chen, Herbert; Sippel, Rebecca S.

2014-01-01

439

Feeding behaviour of juvenile snails ( Helix pomatia) to four plant species grown at elevated atmospheric CO 2  

NASA Astrophysics Data System (ADS)

The feeding behaviour of juveniles of the land snail Helix pomatia was examined in model plant communities consisting of Trifolium repens, Hieracium pilosella, Bromus erectus and Prunella vulgaris that are common species in extensively managed calcareous grasslands in the Swiss Jura mountains. The plant communities were grown either at ambient (350 ppm) or elevated (600 ppm) CO 2 concentrations. Leaves of T. repens and P. vulgaris grown in elevated atmospheric CO 2 had a lower specific leaf area, and leaves of T. repens had lower percentage N on a dry weight basis than leaves grown under ambient CO 2 concentration. Snails fed on all four plant species, but showed a overwhelming preference for T. repens (percentages of total biomass consumed were 91.9% at 350 ppm and 97.6% at 600 ppm). The species-specific feeding intensity of juvenile H. pomatia did not differ between the two treatments. The total dry weight of T. repens consumed by the snails was marginally greater ( P = 0.06) at elevated CO 2, but there were no significant differences in leaf N or leaf area eaten. These findings are similar to numerous other studies showing that invertebrates increase their consumption of plant material to balance reductions in plant N concentrations at elevated CO 2. The leaf biomass, leaf area and amount of nitrogen consumed of the other three plant species did not differ significantly between the two CO 2 treatments. Helix pomatia that fed on plants grown at elevated CO 2 atmosphere showed a larger increase in relative wet weight than those that fed on plants from ambient CO 2 conditions. However, the weight gain of H. pomatia was poorly correlated with amount of plant tissue consumed, so we suggest that the effect of CO 2 on weight gain in H. pomatia was due to a change in the quality of T. repens leaves.

Ledergerber, S.; Leadley, P. W.; Stöcklin, J.; Baur, Bruno

1998-02-01

440

Proton and gamma ray induced gain degradation in bipolar transistor  

NASA Astrophysics Data System (ADS)

This paper describes the results of the effect of 24 MeV proton and (CO)-C-60 gamma-irradiation on the collector characteristic., and forward current gain of commercial bipolar transistor (npn 2N2219A). The transistor has been exposed to these radiations in the biased condition and the collector characteristics and forward current gain have been measured as a function of proton fluence and gamma-dose. The observation is that both the proton and gamma-irradiation induce significant gain degradation in the transistor. The results are discussed in terms of displacement damage produced by energetic protons and gamma-radiation in the bulk of the semiconductor.

Kulkarni, S. R.; Sarma, A.; Joshi, G. R.; Ravindra, M.; Damle, R.

2003-09-01

441

Symmetry breaking and multipeaked solitons in inhomogeneous gain landscapes  

SciTech Connect

We address one-dimensional soliton formation in a cubic nonlinear medium with two-photon absorption and transversally inhomogeneous gain landscape consisting of a single or several amplifying channels. Existence of the solitons requires certain threshold gain while the properties of solitons strongly depend on whether the number of the amplifying channels is odd or even. In the former case, an increase of the gain leads to symmetry breaking, which occurs through the pitchfork bifurcation, and to emergence of a single or several coexisting stable asymmetric modes. In the case of an even number of amplifying channels, we have found only asymmetric stable states.

Kartashov, Yaroslav V.; Vysloukh, Victor A. [ICFO-Institut de Ciencies Fotoniques, and Universitat Politecnica de Catalunya, Mediterranean Technology Park, ES-8860 Castelldefels (Barcelona) (Spain); Konotop, Vladimir V. [Centro de Fisica Teorica e Computacional and Departamento de Fisica, Faculdade de Ciencias, Universidade de Lisboa, Avenida Professor Gama Pinto 2, Lisboa PT-1649-003 (Portugal)

2011-04-15

442

Gain enhancement of microstrip antennas with overlaying parasitic directors  

NASA Astrophysics Data System (ADS)

An experimental study of gain enhancement in microstrip antennas using identical parasitic patch directors is reported. The results indicate that, with two overlying parasitic directors, the gain of a rectangular microstrip antenna is enhanced from 4.7 dB to 10.6 dB, while the 3 dB beamwidth is reduced from 103 deg to 30 deg for the E-plane and from 70 deg to 35 deg for the H-plane. The three-layer electromagnetically coupled patch antenna exhibits similar antenna characteristics to those of the Yagi array, with over 120 dB gain and with about 1 percent bandwidth.

Lee, R. Q.; Lee, K. F.

1988-05-01

443

Gain enhancement of microstrip antennas with overlaying parasitic directors  

NASA Technical Reports Server (NTRS)

An experimental study of gain enhancement in microstrip antennas using identical parasitic patch directors is reported. The results indicate that, with two overlying parasitic directors, the gain of a rectangular microstrip antenna is enhanced from 4.7 dB to 10.6 dB, while the 3 dB beamwidth is reduced from 103 deg to 30 deg for the E-plane and from 70 deg to 35 deg for the H-plane. The three-layer electromagnetically coupled patch antenna exhibits similar antenna characteristics to those of the Yagi array, with over 120 dB gain and with about 1 percent bandwidth.

Lee, R. Q.; Lee, K. F.

1988-01-01

444

Fresnel reflection from a cavity with net roundtrip gain  

SciTech Connect

A planewave incident on an active etalon with net roundtrip gain may be expected to diverge in field amplitude, yet applying the Fresnel formalism to Maxwell's equations admits a convergent solution. We describe this solution mathematically and provide additional insight by demonstrating the response of such a cavity to an incident beam of light. Cavities with net roundtrip gain have often been overlooked in the literature, and a clear understanding of their behavior yields insight to negative refraction in nonmagnetic media, a duality between loss and gain, amplified total internal reflection, and the negative-index lens.

Mansuripur, Tobias S., E-mail: mansuripur@physics.harvard.edu [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States); Mansuripur, Masud [College of Optical Sciences, The University of Arizona, Tucson, Arizona 85721 (United States)

2014-03-24

445

Measuring gain-sharing dividends in acute care hospitals.  

PubMed

Hospitals have responded to industry consolidation by increasing productivity with nonmanagement, group-incentive compensation, known as gain sharing. A nationwide study conducted to obtain quantitative performance data for gain-sharing programs revealed that they are most successful during the initial stages of the program. Many variables affect the size of employee bonuses and the duration of employee support. Employers must identify how to appropriately install their gain-sharing program so that employee motivation, participation, and trust in management are maximized. PMID:8206759

Barbusca, A; Cleek, M

1994-01-01

446

Decoupling approximation design using the peak to peak gain  

NASA Astrophysics Data System (ADS)

Linear system design for accurate decoupling approximation is examined using the peak to peak gain of the error system. The design problem consists in finding values of system parameters to ensure that this gain is small. For this purpose a computationally inexpensive upper bound on the peak to peak gain, namely the star norm, is minimized using a stochastic method. Examples of the methodology's application to tensegrity structures design are presented. Connections between the accuracy of the approximation, the damping matrix, and the natural frequencies of the system are examined, as well as decoupling in the context of open and closed loop control.

Sultan, Cornel

2013-04-01

447

LPV Controller Interpolation for Improved Gain-Scheduling Control Performance  

NASA Technical Reports Server (NTRS)

In this paper, a new gain-scheduling control design approach is proposed by combining LPV (linear parameter-varying) control theory with interpolation techniques. The improvement of gain-scheduled controllers can be achieved from local synthesis of Lyapunov functions and continuous construction of a global Lyapunov function by interpolation. It has been shown that this combined LPV control design scheme is capable of improving closed-loop performance derived from local performance improvement. The gain of the LPV controller will also change continuously across parameter space. The advantages of the newly proposed LPV control is demonstrated through a detailed AMB controller design example.

Wu, Fen; Kim, SungWan

2002-01-01

448

Memristive devices as parameter setting elements in programmable gain amplifiers  

NASA Astrophysics Data System (ADS)

In this paper, we investigate the AC performance of a variable gain amplifier that utilizes an in-house manufactured memristor as a gain setting element. Analysis includes frequency and phase responses as the memristor is programmed at different resistive states. A TiO2-based solid-state memristor was employed in the feedback branch of an inverting voltage amplifier and was programmed externally. We have also observed indications of memcapacitive effects and a correlation with resistive states is presented. We demonstrate that our TiO2 memristive devices, although possessing relatively low ROFF/RON switching ratios (˜10), are versatile and can be used reliably in programmable gain amplifiers.

Berdan, R.; Prodromakis, T.; Salaoru, I.; Khiat, A.; Toumazou, C.

2012-12-01

449

Design of a powered elevator control system. [powered elevator system for modified C-8A aircraft for STOL operation  

NASA Technical Reports Server (NTRS)

The design, fabrication and flight testing of a powered elevator system for the Augmentor Wing Jet STOL Research Aircraft (AWJSRA or Mod C-8A) are discussed. The system replaces a manual spring tab elevator control system that was unsatisfactory in the STOL flight regime. Pitch control in the AWJSRA is by means of a single elevator control surface. The elevator is used for both maneuver and trim control as the stabilizer is fixed. A fully powered, irreversible flight control system powered by dual hydraulic sources was designed. The existing control columns and single mechanical cable system of the AWJSRA have been retained as has been the basic elevator surface, except that the elevator spring tab is modified into a geared balance tab. The control surface is directly actuated by a dual tandem moving body actuator. Control signals are transmitted from the elevator aft quadrant to the actuator by a linkage system that includes a limited authority series servo actuator.

Glende, W. L. B.

1974-01-01

450

Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use.  

PubMed

Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior. PMID:24009567

Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R

2013-01-01

451

Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2  

NASA Astrophysics Data System (ADS)

The ESA satellite CryoSat-2 has been observing Earth's polar regions since April 2010. It carries a sophisticated radar altimeter and aims for the detection of changes in sea ice thickness as well as surface elevation changes of Earth's land and marine ice sheets. This study focuses on the Greenland and Antarctic ice sheets, considering the contemporary elevation of their surfaces. Based on 2 years of CryoSat-2 data acquisition, elevation change maps and mass balance estimates are presented. Additionally, new digital elevation models (DEMs) and the corresponding error maps are derived. Due to the high orbit of CryoSat-2 (88° N/S) and the narrow across-track spacing, more than 99% of Antarctica's surface area is covered. In contrast, previous radar altimeter measurements of ERS1/2 and ENVISAT were limited to latitudes between 81.5° N and 81.5° S and to surface slopes below 1°. The derived DEMs for Greenland and Antarctica have an accuracy which is similar to previous DEMs obtained by satellite-based laser and radar altimetry (Liu et al., 2001; Bamber et al., 2009, 2013; Fretwell et al., 2013; Howat et al., 2014). Comparisons with ICESat data show that 80% of the CryoSat-2 DEMs have an error of less than 3 m ± 30 m. For both ice sheets the surface elevation change rates between 2011 and 2012 are presented at a resolution of 1 km. Negative elevation changes are concentrated at the west and south-east coast of Greenland and in the Amundsen Sea embayment in West Antarctica (e.g. Pine Island and Thwaites glaciers). They agree well with the dynamic mass loss observed by ICESat between 2003 and 2008 (Pritchard et al., 2009). Thickening occurs along the main trunk of Kamb Ice Stream and in Dronning Maud Land. While the former is a consequence of an ice stream stagnated ∼150 years ago (Rose, 1979; Retzlaff and Bentley, 1993), the latter represents a known large-scale accumulation event (Lenaerts et al., 2013). This anomaly partly compensates for the observed increased volume loss in West Antarctica. In Greenland the findings reveal an increased volume loss of a factor of 2 compared to the period 2003 to 2008. The combined volume loss of Greenland and Antarctica for the period 2011 and 2012 is estimated to be -448 ± 122 km3 yr-1.

Helm, V.; Humbert, A.; Miller, H.

2014-03-01

452

The bridge to space: Elevator sizing & performance analysis  

NASA Astrophysics Data System (ADS)

The Bridge to Space (BTS), an advanced system concept designed to significantly reduce payload-to-space delivery costs, consists of two major elements as seen in Figure 1: a long Space Elevator cable structure and an aircraft-like Sub-Orbital launch vehicle (SOLV). Preliminary estimates indicate the BTS can meet a launch cost target of $100/lb for 3rd generation launch systems. Previous papers have described the operational concept for launching payloads with the Bridge to Space (Marshall & Mottinger, 2000). These operations include payload transfer from the SOLV to the Space Elevator's Earth Transfer Station (ETS), payload translation along the elevator with a moving carriage platform and processing/transfer/release of the payload at the elevator's Apex Station (AS) as required, or payload release at the uppermost point of the elevator, the Space Transfer Station (STS). This paper will focus on sizing and performance modeling of the Space Elevator segment of the overall Bridge to Space. An elevator model has been developed to accept varying input parameters to determine outputs such as elevator mass and length, and altitude change/reboost requirements during payload transfer operations. Some of the key input variables include payload mass, ETS altitude and handoff velocity with the SOLV, and cable stress/density ratio. Sensitivity analyses have been performed with the model to determine the optimum altitude, velocity and size of the elevator for a given payload mass. Preliminary results of these sensitivity analyses are presented. The paper also includes a discussion of alternate concepts for the Space Elevator that could improve performance (i.e., minimize reboost fuel usage), based upon results of the model described above. Specifically, techniques to reduce the aerodynamic drag of the elevator's lower end and reduction of the overall elevator length and mass are discussed. The paper concludes with a summary of key results and lists technology development areas that would improve elevator performance. .

Marshall, Leland S.; Ladner, Daniel R.; McCandless, Bruce

2002-01-01

453

The ontogeny of individual vs. stand-level responses to elevated CO[sub 2  

SciTech Connect

Plant species appear to differ widely in terms of growth responses to elevated CO[sub 2]; however, most existing comparative data are limited to observations made early in the ontogeny on plants grown an isolated individuals. We examined growth responses to elevated CO[sub 2] in nine species of herbaceous plants, including three erect annuals (genera included Abutilon, Ambrosia, and Cassia) three grasses (Dactylis, Lolium, Panicum), and three rosette species (Plantago, Rumex, and Taraxacum), each grown as isolated individuals and as dense monocultures in ambient (350 ppm) and 2X ambient (700 ppm) CO[sub 2] atmospheres in a glasshouse over 5-6 mo. Soil texture, depth, and nutrient conditions matched those of waste areas in western Massachusetts. On the basis of non-destructive estimates of leaf area index (LAI), all species exhibited large early growth responses to CO[sub 2], ranging up to 50-120%. However, later in stand ontogeny LAI consistently converged between CO[sub 2] treatments, eventually becoming lower at ambient than at elevated CO[sub 2] in most species. Final total biomass effects at the stand level were in the range of 0-10% enhancements, with no consistent differences among growth forms. Reproductive output was significantly reduced by elevated CO[sub 2] in several species, including some with very high early growth enhancements. Our results strongly suggest that CO[sub 2] effects on early growth of individual plants greatly overestimate longer term effects on species performance and net ecosystem carbon gain.

Thomas, S.C.; Jasienski, M.; Bazzaz, F.A. (Harvard Univ., Cambridge, MA (United States))

1994-06-01

454

26 CFR 7.105-2 - Substantial gainful activity.  

Code of Federal Regulations, 2013 CFR

...CONTINUED) TEMPORARY INCOME TAX REGULATIONS UNDER THE TAX REFORM ACT OF 1976 § 7.105-2 Substantial gainful activity...institutional therapy or training, school attendance, clubs, social programs, and similar activities is not substantial...

2013-04-01

455

26 CFR 7.105-2 - Substantial gainful activity.  

Code of Federal Regulations, 2014 CFR

...CONTINUED) TEMPORARY INCOME TAX REGULATIONS UNDER THE TAX REFORM ACT OF 1976 § 7.105-2 Substantial gainful activity...institutional therapy or training, school attendance, clubs, social programs, and similar activities is not substantial...

2014-04-01

456

26 CFR 7.105-2 - Substantial gainful activity.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) TEMPORARY INCOME TAX REGULATIONS UNDER THE TAX REFORM ACT OF 1976 § 7.105-2 Substantial gainful activity...institutional therapy or training, school attendance, clubs, social programs, and similar activities is not substantial...

2012-04-01

457

26 CFR 7.105-2 - Substantial gainful activity.  

Code of Federal Regulations, 2011 CFR

...CONTINUED) TEMPORARY INCOME TAX REGULATIONS UNDER THE TAX REFORM ACT OF 1976 § 7.105-2 Substantial gainful activity...institutional therapy or training, school attendance, clubs, social programs, and similar activities is not substantial...

2011-04-01

458

RESEARCH ARTICLE Open Access Gaining insight into benzodiazepine prescribing  

E-print Network

RESEARCH ARTICLE Open Access Gaining insight into benzodiazepine prescribing in General Practice of General Practice, has been compiling since 1993 in a network of 90 GPs working mainly in solo practices

Paris-Sud XI, Université de

459

Increased gain of channel intensifier tubes by pulsed biasing  

SciTech Connect

Although the most common use of proximity-focused channel intensifier tubes (CITs) is as optical image amplifiers, electrical gating allows them to be used as fast shutters. Except for gating, however, the effects of imposing transient or pulsed changes on CIT biases have received little attention in the literature. It would be desirable in many applications to attain the maximum possible gain, but not at the expense of reduced signal-to-noise ratio (SNR). In the experiments described here, we used pulsed biasing to increase gain; our measurements show a marked increase in gain over the dc gain without the increase in electronic noise and risk of damage that higher dc potentials create. 7 refs., 4 figs.

Noel, B.W.; Cates, M.R.; Franks, L.A.

1987-09-01

460

Review of health and productivity gains from better IEQ  

SciTech Connect

The available scientific data suggest that existing technologies and procedures can improve indoor environmental quality (IEQ) in a manner that significantly increases productivity and health. While there is considerable uncertainty in the estimates of the magnitudes of productivity gains that may be obtained, the projected gains are very large. For the U.S., the estimated potential annual savings and productivity gains are $6 to $14 billion from reduced respiratory disease, $2 to $4 billion from reduced allergies and asthma, $10 to $30 billion from reduced sick building syndrome symptoms, and $20 to $160 billion from direct improvements in worker performance that are unrelated to health. Productivity gains that are quantified and demonstrated could serve as a strong stimulus for energy efficiency measures that simultaneously improve the indoor environment.

Fisk, William J.

2000-08-01

461

Scientists Gain New Insights into Genetic Mechanisms of Ankylosing Spondylitis  

MedlinePLUS

... January 2012 Scientists Gain New Insights into Genetic Mechanisms of Ankylosing Spondylitis New research supported, in part, ... scientists a step closer to understanding the genetic mechanisms underlying ankylosing spondylitis, a chronic inflammatory form of ...

462

Healthy Weight Gain for Teens: A Guide for Parents  

MedlinePLUS

... they are growing taller, exercising a lot with sports, or they might simply have a high metabolism ( ... gain but remember to have discussions about school, sports, current events, and feelings with your teen. Written ...

463

Design of a variable gain amplifier for an ultrawideband receiver  

E-print Network

Reza Langari Head of Department, G.Huang August 2005 Major Subject: Electrical Engineering iii ABSTRACT Design of a Variable Gain Amplifier for an Ultra Wideband Receiver. (August 2005) Sivasankari Krishnanji, B.E (Hons...

Krishnanji, Sivasankari

2005-11-01

464

Predicting FCI gain with a nonverbal intelligence test  

NASA Astrophysics Data System (ADS)

We have administered both a commercial, nonverbal intelligence test (the GAMA) and Lawson's Classroom Test of Scientific Reasoning to students in two introductory physics classes to determine if either test can successfully predict normalized gains on the Force Concept Inventory. Since gain on the FCI is known to be related to gender, we adopted a linear model with gain on the FCI as the dependent variable and gender and a test score as the independent variables. We found that the GAMA score did not predict a significant amount of variation beyond gender. Lawson's test, however, did predict a small but significant variation beyond gender. When simple linear regressions were run separately for males and females with the Lawson score as a predictor, we found that the Lawson score did not significantly predict gains for females but was a marginally significant predictor for males.

Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W.

2013-01-01

465

Gain scheduling for geometrically nonlinear flexible space structures  

E-print Network

A gain-scheduling approach for the control of geometrically nonlinear structures is developed. The objective is to improve performance over current linear design techniques that are applied to the same control problem. The ...

Yung, Jeremy Hoyt, 1971-

2002-01-01

466

Mechanisms of intron gain and loss in Cryptococcus  

E-print Network

Background: Genome comparisons across deep phylogenetic divergences have revealed that spliceosomal intron gain and loss are common evolutionary events. However, because of the deep divergences involved in these comparisons, ...

Neafsey, Daniel E.

467

18 CFR 11.13 - Energy gains calculations.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Energy gains calculations. 11.13 Section 11...Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER...

2010-04-01

468

18 CFR 11.13 - Energy gains calculations.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Energy gains calculations. 11.13 Section 11...Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER...

2011-04-01

469

Perspective methods for the generation of COIL gain medium  

NASA Astrophysics Data System (ADS)

An ejector nozzle bank powered by centrifugal bubbling SOG is considered like highly efficient gain generating system for COIL. A high potential recovered pressure ~100 torr of the gain medium flow with a small signal gain higher than 1% cm -1 and low oxygen plenum pressure has been demonstrated. A centrifugal bubbling SOG is an efficient source of oxygen at high pressure with high depletion of the BHP in the single burn dawn. A high 0 II(1?) yield and chlorine utilization higher than 90% have been obtained at chlorine gas loading up to 6 mmole/s per 1 cm2 of the bubbler surface. The ejector COIL powered by centrifugal bubbling SOG demonstrated ~25% of chemical efficiency with specific power 6 kJ per 1 litre of the BHP in the single burn dawn. The combination of centrifugal bubble SOG with ejector nozzle bank can be considered as a promising gain medium flow generation system for COIL.

Zagidullin, Marsel V.; Nikolaev, Valery D.; Svistun, Michael I.; Khvatov, Nikolay A.

2007-04-01

470

Predicting FCI gain with a nonverbal intelligence test  

NSDL National Science Digital Library

We have administered both a commercial, nonverbal intelligence test (the GAMA) and Lawsonâs Classroom Test of Scientific Reasoning to students in two introductory physics classes to determine if either test can successfully predict normalized gains on the Force Concept Inventory. Since gain on the FCI is known to be related to gender, we adopted a linear model with gain on the FCI as the dependent variable and gender and a test score as the independent variables. We found that the GAMA score did not predict a significant amount of variation beyond gender. Lawsonâs test, however, did predict a small but significant variation beyond gender. When simple linear regressions were run separately for males and females with the Lawson score as a predictor, we found that the Lawson score did not significantly predict gains for females but was a marginally significant predictor for males.

Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W.

2014-02-01

471

Gain-assisted hybrid-superlens hyperlens for nano imaging.  

PubMed

We propose an innovative active imaging device named gain-assisted hybrid-superlens hyperlens and examine its resolving power theoretically. This semi-cylindrical device consists of a core of semi-cylindrical super-lens and a half cylindrical outer shell of hyperlens. Both the superlens and hyperlens parts of the device are appropriately designed multi-layered metal-dielectric structures having indefinite eigenvalues of dielectric tensors. The dielectric layers of the hyperlens are doped with Coumarin, which play the role of gain medium. The gain medium is analyzed thoroughly using a generic four-level system model, and the permittivity of the gain medium is extracted from this analysis for simulating the imaging characteristics of the device. According to our simulation at wavelength of 365 nm, an excellent resolution power much better than the diffraction limit value can be achieved. PMID:23037445

Wang, Yao Ting; Cheng, Bo Han; Ho, You Zhe; Lan, Yung-Chiang; Luan, Pi-Gang; Tsai, Din Ping

2012-09-24

472

Elementary modes of coupled oscillators with balanced loss and gain  

E-print Network

We provide a reduction of a set of two coupled oscillators with balanced loss and gain in their elementary modes. A possible method of quantization based on these elementary modes, in the framework of $PT$ symmetric quantum mechanics is indicated.

Rabin Banerjee; Pradip Mukherjee

2014-08-21

473

Losing it: The Influence of Losses on Individuals' Normalized Gains  

NSDL National Science Digital Library

Researchers and practitioners routinely use the normalized gain (Hake, 1998) to evaluate the effectiveness of instruction. Normalized gain (g) has been useful in distinguishing active engagement from traditional instruction. Recently, concerns were raised about normalized gain because it implicitly neglects retention (or, equivalently, "losses"). That is to say, g assumes no right answers become wrong after instruction. We analyze individual standardized gain (G) and loss (L) in data collected at Harvard University during the first five years that Peer Instruction was developed. We find that losses are non-zero, and that losses are larger among students with lower pre-test performances. These preliminary results warrant further research, particularly with different student populations, to establish whether the failure to address loss changes the conclusions drawn from g.

Miller, Kelly; Lasry, Nathaniel; Reshef, Orad; Dowd, Jason E.; Araujo, Ives; Mazur, Eric

2010-12-31

474

Minimizing gain transient dynamics by optimizing the erbium concentration and cavity length of a gain clamped EDFA.  

PubMed

Erbium doped fiber amplifier (EDFA) gain transient dynamics are studied in the context of their application in optically reconfigurable networks. We address the question of how to design the EDFA in order to minimize the gain transients present in the output signals of the EDFA when the system is optically reconfigured such that the total average input power levels and wavelengths are changed. Both experimental measurements and theoretical simulations show that the amplitude transients depend on the length of the erbium doped fiber (EDF) and the erbium concentration. We show how it may be possible to reduce the gain transients by appropriate design of the EDFA. PMID:19498777

Chan, P; Tsang, H

2005-09-19

475

Gain-scheduled filtering for parameter-dependent digital systems  

Microsoft Academic Search

This paper deals with the design of gain-scheduled filters, that is filters whose state-space realization is depending on some plant parameters available in real time. Similarly to well-recognized advantages in control theory, gain-scheduled filters are expected to provide enhanced performance in comparison with customary non-adjustable filters. Our construction technique is based on a nonlinear fractional transformation representation of the system

N. T. Hoang; H. D. Tuan; P. Apkarian; S. Hosoe

2002-01-01

476

High gain amplifiers: Power oscillations and harmonic generation  

SciTech Connect

We discuss the power oscillations in saturated high gain free electron laser amplifiers and show that the relevant period can be written in terms of the gain length. We use simple arguments following from the solution of the pendulum equation in terms of Jacobi elliptic functions. Nontrivial effects due to nonlinear harmonic generation and inhomogeneous broadening are discussed too, as well as the saturated dynamics of short pulses.

Dattoli, G.; Ottaviani, P. L.; Pagnutti, S. [ENEA, Dipartimento Tecnologie Fisiche e Nuovi Materiali, Centro Ricerche Frascati, C.P. 65-00044 Frascati, Rome (Italy)

2007-08-01

477

Pharmacological management of atypical antipsychotic-induced weight gain.  

PubMed

Excessive bodyweight gain was reported during the 1950s as an adverse effect of typical antipsychotic drug treatment, but the magnitude of bodyweight gain was found to be higher with the atypical antipsychotic drugs that were introduced after 1990. Clozapine and olanzapine produce the greatest bodyweight gain, ziprasidone and aripiprazole have a neutral influence, and quetiapine and risperidone cause an intermediate effect. In the CATIE study, the percentage of patients with bodyweight gain of >7% compared with baseline differed significantly between the antipsychotic drugs, i.e. 30%, 16%, 14%, 12% and 7% for olanzapine, quetiapine, risperidone, perphenazine (a typical antipsychotic) and ziprasidone, respectively (p<0.001). Appetite stimulation is probably a key cause of bodyweight gain, but genetic polymorphisms modify the bodyweight response during treatment with atypical antipsychotics. In addition to nutritional advice, programmed physical activity, cognitive-behavioural training and atypical antipsychotic switching, pharmacological adjunctive treatments have been assessed to counteract excessive bodyweight gain. In some clinical trials, nizatidine, amantadine, reboxetine, topiramate, sibutramine and metformin proved effective in preventing or reversing atypical antipsychotic-induced bodyweight gain; however, the results are inconclusive since few randomized, placebo-controlled clinical trials have been conducted. Indeed, most studies were short-term trials without adequate statistical power and, in the case of metformin, nizatidine and sibutramine, the results are contradictory. The tolerability profile of these agents is adequate. More studies are needed before formal recommendations on the use of these drugs can be made. Meanwhile, clinicians are advised to use any of these adjunctive treatments according to their individual pharmacological and tolerability profiles, and the patient's personal and family history of bodyweight gain and metabolic dysfunction. PMID:18484791

Baptista, Trino; ElFakih, Yamily; Uzcátegui, Euderruh; Sandia, Ignacio; Tálamo, Eduardo; Araujo de Baptista, Enma; Beaulieu, Serge

2008-01-01

478

Thermodynamic properties of uranium in Ga-In based alloys  

NASA Astrophysics Data System (ADS)

Activity of uranium was determined in gallium, indium and gallium-indium eutectic (21.8 wt.% In) based alloys between 573 and 1073 K employing the electromotive force method. In two-phase U-Ga-In alloys, uranium forms the intermetallic compound UGa3. Activity coefficients and solubility of uranium in Ga-In eutectic were also determined in the same temperature range. Partial thermodynamic functions of ?-U in saturated alloys with gallium, indium and Ga-In eutectic were calculated.

Volkovich, V. A.; Maltsev, D. S.; Yamshchikov, L. F.; Melchakov, S. Yu; Shchetinskiy, A. V.; Osipenko, A. G.; Kormilitsyn, M. V.

2013-07-01

479

Automatic tuning of gain-scheduled control for asymmetrical processes  

Microsoft Academic Search

This paper presents an automatic tuning procedure for gain-scheduled control of asymmetrical processes. A modified relay feedback is employed to obtain a frequency response estimation for the dual dynamics of the asymmetrical process, where a novel gain-matching and frequency-matching method is developed to correct an asymmetry phenomenon associated with the oscillations induced from a direct application of basic relay feedback.

K. K. Tan; Q.-G. Wang; T. H. Lee; C. H. Gan

1998-01-01

480

Gain-scheduled wheel slip control in automotive brake systems  

Microsoft Academic Search

A wheel slip controller is developed and experimentally tested in a car equipped with electromechanical brake actuators and a brake-by-wire system. A gain scheduling approach is taken, where the vehicle speed is viewed as a slowly time-varying parameter and the model is linearized about the nominal wheel slip. Gain matrices for the different operating conditions are designed using an LQR

Tor A. Johansen; Idar Petersen; Jens Kalkkuhl; Jens Ludemann

2003-01-01

481

Spatial gain measurements in a chemical oxygen iodine laser (COIL)  

Microsoft Academic Search

The spatial distribution of small signal gain has been investigated on the RADICL device, a supersonic chemical oxygen-iodine laser (COIL). A frequency-stabilized, narrow linewidth diode laser system operating on the F=3?F=4 hyperfine levels of the (2 P1\\/2) to (2P3\\/2) spin-orbit transition in atomic iodine was used as a small signal probe. A peak gain of 1.2%\\/cm was measured along the

R. F. Tate; B. S. Hunt; C. A. Helms; K. A. Kruesdell; G. D. Hager

1995-01-01

482

A SiGe MMIC variable gain cascode amplifier  

Microsoft Academic Search

A silicon-germanium variable gain cascode amplifier has been developed to combine the functionality of an amplifier and an attenuator into one monolithic microwave integrated circuit (MMIC). The cascode amplifier, which was designed for a 7-11 GHz frequency range, achieved a gain of 12.5 dB, an input return loss of 7.5 dB, and an output return loss of 12.5 dB. The

Qasim Chaudhry; Raul Alidio; Glenn Sakamoto; Terry Cisco

2002-01-01

483

Computer simulation of space station computer steered high gain antenna  

NASA Technical Reports Server (NTRS)

The mathematical modeling and programming of a complete simulation program for a space station computer-steered high gain antenna are described. The program provides for reading input data cards, numerically integrating up to 50 first order differential equations, and monitoring up to 48 variables on printed output and on plots. The program system consists of a high gain antenna, an antenna gimbal control system, an on board computer, and the environment in which all are to operate.

Beach, S. W.

1973-01-01

484

The distribution of gains in uniformly multiplying avalanche photodiodes: Theory  

Microsoft Academic Search

Expressions are derived for the probabilityP_{n,m}that a pulse initiated bynelectrons (or holes) in a uniformly multiplying semiconductor diode will result in a total number of electrons (or holes)m, to give a gainm\\/n, and for the probabilityQ_{n,m}that the gain will bem\\/nor greater. It is shown that the distributions are far from Gaussian. The gain distributionP_{1,m}for a single photoelectron, for example, is

R. J. McIntyre

1972-01-01

485

High-gain GaAs MSM photodetector  

NASA Astrophysics Data System (ADS)

Photodetectors with metal-semiconductor -metal (MSM) structures having very high quan turn efficiency are investigated to identify the gain mechanism. From the temperature dependence studies impact ionisation of carriers in a region under the edge of the cathode is shown to be the predominant gain mechanism. Metal-Semiconductors-Metal (MSM) structure has recently emerged" 2 as an attractive device for photodetection due to its simple planar tech nology which can be easily adapted to optoelec tronic integration. The other features of MSM photodetector are their high sensitivity, low capacitance, low dark current and high speed. Substatial amount of work has been done on GaAs MSM photodiodes which are useful in near infrared wavelength regime. Devices with very low dark current (lOOpA at 1OV for 200x200pm geometry) and low rise and fall times (23 and 55 ps respecti vely) have been recently fabricated on semi-insu lating (SI) GaAs substrates1. The other interest ing feature of MSM structure is that it has in ternal gain. Despite intensive study of these devices there is still confusion about the physi cal origin of the gain in these devices. Ito et a13 attribute the gain to hole injection at the forward biased anode contact. Measurements of Zirngibl et al however, point to avalanche mechanism of gain in these devices. In this paper we report the results of experimental in vestigation of gain mechanism in GaAs MSM struc tures which have extremely high gain (100).

Karulkar, V. T.; Purandare, S. C.; Srivastava, Atul K.; Arora, B. M.

1992-12-01

486

Massage Therapy Facilitates Weight Gain in Preterm Infants  

Microsoft Academic Search

Studies from several labs have documented a 31 to 47% greater weight gain in preterm new-borns receiving massage therapy (three 15-min sessions for 5–10 days) compared with standard medical treatment. Although the underlying mechanism for this relationship between massage therapy and weight gain has not yet been established, possibilities that have been explored in studies with both humans and rats

Tiffany Field

2001-01-01

487

[Mechanisms for weight gain during blood glucose normalization].  

PubMed

Secondary failure to dietary and maximal oral treatment leads to insulin therapy in type 2 diabetic patients. However, weight gain is a frequent side effect of insulin therapy in these patients. Mechanisms for this weight gain are complex. Insulin 1) reduces glycosuria and its caloric expenditure; 2) stimulates the stockage of fatty acids into triglycerides in adipose tissue, thus favoring an increase in adipose mass; 3) yields a positive nitrogen balance through an inhibition of muscle proteolysis, thus favoring an increase in lean mass. Most studies report an average 6 kg weight gain during the first year following the initiation of insulin therapy in type 2 diabetic patients. Analysing body composition variations shows that weight gain results both from an increase in fat mass (mean 63%) and an increase in lean mass (mean 37%). Preexisting obesity does not influence this weight gain. Finally, the 10 year-follow up of UKPDS showed a beneficial effect of insulin therapy on microangiopathy prevention, without increasing cardiovascular mortality as compared with type 2 diabetic patients on oral treatment. Thus, while weight gain seems mandatory, it should not refrain from initiating insulin therapy in poorly controlled type 2 diabetic patients, as its expected beneficial effects on the prevention of microangiopathy seem well established. PMID:10945152

Laville, M; Andreelli, F

2000-06-01

488

Controlled hydrostatic sinus elevation: a novel method of elevating the sinus membrane.  

PubMed

Maxillary sinus elevation surgery has been practiced successfully over the past several decades with good outcomes, but tears and perforations still occur in significant numbers. The presumed cause of these problems is the fact that all methods currently used place "point sources" of lifting pressure on the Schneiderian membrane. A new procedure, controlled hydrostatic sinus lift, is presented herein as a safer, more controlled "lifting pressure" which simultaneously places equal force per square millimeter of bone-membrane interface. Hydraulic pressure in a closed system places equal pressure on all surfaces within the system, thereby eliminating "point sources" of pressure and gently elevating the Schneiderian membrane equally at all points of attachment. This controlled hydrostatic sinus lift procedure is accomplished by using a calibrated, hand-controlled pump and in-line pressure sensor meter. PMID:22067599

Kao, Daniel W K; DeHaven, Harold A

2011-12-01

489

Spatiotemporal variability of increasing temperature impacts on grassland vegetation along an elevation transect in the Alps  

NASA Astrophysics Data System (ADS)

Different manipulative approaches have been developed to study and quantify impacts of temperature increase on grassland ecosystems. Many of them share the problem of unwanted effects on the surrounding microclimatic conditions. Transplantation of grassland mesocosms along elevation gradients can be a realistic alternative, although with some restrictions. Here we present 3 years of data from a double-transplant-experiment, were 70*70*20cm grassland turves were transplanted at two elevations from 2000m to 1500m a.s.l. and from 1500m to 1000m a.s.l. respectively, along an inner-alpine elevation gradient in the Vinschgau Valley (South Tyrol, I). All donor and receiving sites are comparable regarding land use (meadows), soil conditions or exposition and are located within a few km's distance ensuring comparable weather conditions apart from the intended air temperature (0.54°K/100m) and annual precipitation (20mm/100m) lapse rate. Phytodiversity and above ground net primary production (ANPP) of the transplanted mesocosms were assessed and compared with locally transplanted monoliths of the respective donor site. Furthermore, growth dynamics was continuously observed throughout the vegetation season with a non-destructive method based on measurement of light (photosynthetic active radiation) extinction within the canopy. After 3 years no significant changes in absolute species numbers has been detected at all, whereas slight variations have been observed regarding species composition. Those shifts could be differentiated both to transplantation artifacts and effects of the elevated temperature. Total aboveground phytomass, unsurprisingly, showed higher values on transplanted (lower) mesocosms, however: data from single cuts and growth rate analysis reveal differing effects between the two transplantation steps as well as over the course of the vegetation period. Transplanted plots from 2000m to 1500m showed continuously higher productivity from spring to autumn, whereas on the lower transplants (from 1500m to 1000m) during summer months the temperature benefit gets balanced by higher evapotranspiration rates, resulting in more frequent drought stress. Summarizing, gained experiences confirm well-designed transplant approach to be an interesting alternative for mid- to longterm simulations of future climate conditions in grassland ecosystems. Furthermore, results indicate that the impact of increasing temperatures in the studied grassland highly depends on elevation and acts rather by a prolongation of the vegetation period than by elevated summer temperatures.

Niedrist, Georg; Obojes, Nikolaus; Bertoldi, Giacomo; Della Chiesa, Stefano; Tasser, Erich; Tappeiner, Ulrike

2013-04-01

490

Phytochemical changes in leaves of subtropical grasses and fynbos shrubs at elevated atmospheric CO 2 concentrations  

NASA Astrophysics Data System (ADS)

The effects of elevated atmospheric CO 2 concentrations on plant polyphenolic, tannin, nitrogen, phosphorus and total nonstructural carbohydrate concentrations were investigated in leaves of subtropical grass and fynbos shrub species. The hypothesis tested was that carbon-based secondary compounds would increase when carbon gain is in excess of growth requirements. This premise was tested in two ecosystems involving plants with different photosynthetic mechanisms and growth strategies. The first ecosystem comprised grasses from a C 4-dominated, subtropical grassland, where three plots were subjected to three different free air CO 2 enrichment treatments, i.e., elevated (600 to 800 ?mol mol -1), intermediate (400 ?mol mol -1) and ambient atmospheric CO 2. One of the seven grass species, Alloteropsis semialata, had a C 3 photosynthetic pathway while the other grasses were all C 4. The second ecosystem was simulated in a microcosm experiment where three fynbos species were grown in open-top chambers at ambient and 700 ?mol mol -1 atmospheric CO 2 in low nutrient acid sands typical of south western coastal and mountain fynbos ecosystems. Results showed that polyphenolics and tannins did not increase in the grass species under elevated CO 2 and only in Leucadendron laureolum among the fynbos species. Similarly, foliar nitrogen content of grasses was largely unaffected by elevated CO 2, and among the fynbos species, only L. laureolum and Leucadendron xanthoconus showed changes in foliar nitrogen content under elevated CO 2, but these were of different magnitude. The overall decrease in nitrogen and phosphorus and consequent increase in C:N and C:P ratio in both ecosystems, along with the increase in polyphenolics and tannins in L. laureolum in the fynbos ecosystem, may negatively affect forage quality and decomposition rates. It is concluded that fast growing grasses do not experience sink limitation and invest extra carbon into growth rather than polyphenolics and tannins and show small species-specific chemical changes at elevated atmospheric CO 2 concentrations. Responses of fynbos species are varied and were species-specific.

Hattas, D.; Stock, W. D.; Mabusela, W. T.; Green, I. R.

2005-07-01

491

The surface elevation table: marker horizon method for measuring wetland accretion and elevation dynamics  

USGS Publications Warehouse

Tidal wetlands are highly sensitive to processes that affect their elevation relative to sea level. The surface elevation table–marker horizon (SET–MH) method has been used to successfully measure these processes, including sediment accretion, changes in relative elevation, and shallow soil processes (subsidence and expansion due to root production). The SET–MH method is capable of measuring changes at very high resolution (±millimeters) and has been used worldwide both in natural wetlands and under experimental conditions. Marker horizons are typically deployed using feldspar over 50- by 50-cm plots, with replicate plots at each sampling location. Plots are sampled using a liquid N2 cryocorer that freezes a small sample, allowing the handling and measurement of soft and easily compressed soils with minimal compaction. The SET instrument is a portable device that is attached to a permanent benchmark to make high-precision measurements of wetland surface elevation. The SET instrument has evolved substantially in recent decades, and the current rod SET (RSET) is widely used. For the RSET, a 15-mm-diameter stainless steel rod is pounded into the ground until substantial resistance is achieved to establish a benchmark. The SET instrument is attached to the benchmark and leveled such that it reoccupies the same reference plane in space, and pins lowered from the instrument repeatedly measure the same point on the soil surface. Changes in the height of the lowered pins reflect changes in the soil surface. Permanent or temporary platforms provide access to SET and MH locations without disturbing the wetland surface.

Callaway, John C.; Cahoon, Donald R.; Lynch, James C.

2014-01-01

492

Safe electrical design of mine elevator control systems  

SciTech Connect

A mine elevator recently experienced an ascending car overspeed accident resulting in serious injuries to four passengers. Although the four miners laid down on the floor prior to impact, the miners struck the ceiling of the elevator car as it collided into the overhead structure at an estimated speed four times faster than normal. Several electrical design precautions can be implemented to prevent elevator control system failures. This paper examines safe electrical design of elevator control systems. Supplemental circuits and devices which improve the safety integrity and maintenance of the elevator control system are presented. These circuits and devices provide protection that eliminates the potential hazard and significantly reduces the possibility of a mine elevator accident.

Barkand, T.D. [Mine Safety and Health Administration, Pittsburgh, PA (United States)

1995-12-31

493

Safe electrical design of mine elevator control systems  

SciTech Connect

A mine elevator recently experienced an ascending-car overspeed accident, resulting in serious injuries to four passengers. Although the four miners laid down on the floor prior to impact, the miners struck the ceiling of the elevator car as it collided into the overhead structure at an estimated speed four times faster than normal. Several electrical design precautions can be implemented to prevent elevator control system failures. This paper examines safe electrical design of elevator control systems. Supplemental circuits and devices which improve the safety integrity and maintenance of the elevator control system are presented. These circuits and devices provide protection that eliminates the potential hazard and significantly reduces the possibility of a mine elevator accident.

Barkand, T.D. [Mine Safety and Health Administration, Pittsburgh, PA (United States)] [Mine Safety and Health Administration, Pittsburgh, PA (United States)

1997-03-01

494

Svalbard glacier elevation changes and contribution to sea level rise  

Microsoft Academic Search

We compare satellite altimetry from the Ice, Cloud, and Land Elevation Satellite (ICESat, 2003-2007) to older topographic maps and digital elevation models (1965-1990) to calculate long-term elevation changes of glaciers on the Svalbard Archipelago. Results indicate significant thinning at most glacier fronts with either slight thinning or thickening in the accumulation areas, except for glaciers that surged which show thickening

Christopher Nuth; Geir Moholdt; Jack Kohler; Jon Ove Hagen; Andreas Kääb

2010-01-01

495

Svalbard glacier elevation changes and contribution to sea level rise  

Microsoft Academic Search

We compare satellite altimetry from the Ice, Cloud, and Land Elevation Satellite (ICESat, 2003–2007) to older topographic maps and digital elevation models (1965–1990) to calculate long-term elevation changes of glaciers on the Svalbard Archipelago. Results indicate significant thinning at most glacier fronts with either slight thinning or thickening in the accumulation areas, except for glaciers that surged which show thickening

Christopher Nuth; Geir Moholdt; Jack Kohler; Jon Ove Hagen; Andreas Kääb

2010-01-01

496

Morphological Filling of Digital Elevation Models  

NASA Astrophysics Data System (ADS)

In this paper a new approach for a more detailed post processing and filling of digital elevation models (DEMs) in urban areas is presented. To reach the required specifications in a first step the errors in digital surface models (DSMs) generated by dense stereo algorithms are analyzed and methods for detection and classification of the different types of errors are implemented. Subsequently the classified erroneous areas are handled in separate manner to eliminate outliers and fill the DSM properly. The errors which can be detected in DSMs range from outliers - single pixels or small areas containing extremely high or low values - over noise from mismatches, single small holes to occlusions, where large areas are not visible in one of the images of the stereo pair. To validate the presented method artificial DSMs are generated and superimposed with all different kinds of described errors like noise (small holes cut in), outliers (small areas moved up/down), occlusions (larger areas beneath steep walls) and so on. The method is subsequently applied to the artificial DSMs and the resulting filled DSMs are compared to the original artificial DSMs without the introduced errors. Also the method is applied to stereo satellite generated DSMs from the ISPRS Comission 1 WG4 benchmark dataset and the results are checked with the also provided first pulse laser DSM data. Finally the results are discussed, strengths and weaknesses of the approach are shown and suggestions for application and optimization are given.

Krauß, T.; d'Angelo, P.

2011-09-01

497

Elevated temperature biaxial fatigue. Final Report  

SciTech Connect

A 3 year experimental program for studying elevated temperature biaxial fatigue of a nickel based alloy Hastelloy-X has been completed. A new high temperature fatigue test facility with unique capabilities has been developed. Effort was directed toward understanding multiaxial fatigue and correlating the experimental data to the existing theories of fatigue failure. The difficult task of predicting fatigue lives for nonproportional loading was used as an ultimate test for various life prediction methods being considered. The primary means of reaching improved understanding were through several critical nonproportional loading experiments. The direction of cracking observed on failed specimens was also recorded and used to guide the development of the theory. Cyclic deformation responses were permanently recorded digitally during each test. It was discovered that the cracking mode switched from primarily cracking on the maximum shear planes at room temperature to cracking on the maximum normal strain planes at 649 C. In contrast to some other metals, loading path in nonproportional loading had little effect on fatigue lives. Strain rate had a small effect on fatigue lives at 649 C. Of the various correlating parameters the modified plastic work and octahedral shear stress were the most successful.

Jordan, E.H.

1985-10-01

498

Elevating crop disease resistance with cloned genes.  

PubMed

Essentially all plant species exhibit heritable genetic variation for resistance to a variety of plant diseases caused by fungi, bacteria, oomycetes or viruses. Disease losses in crop monocultures are already significant, and would be greater but for applications of disease-controlling agrichemicals. For sustainable intensification of crop production, we argue that disease control should as far as possible be achieved using genetics rather than using costly recurrent chemical sprays. The latter imply CO? emissions from diesel fuel and potential soil compaction from tractor journeys. Great progress has been made in the past 25 years in our understanding of the molecular basis of plant disease resistance mechanisms, and of how pathogens circumvent them. These insights can inform more sophisticated approaches to elevating disease resistance in crops that help us tip the evolutionary balance in favour of the crop and away from the pathogen. We illustrate this theme with an account of a genetically modified (GM) blight-resistant potato trial in Norwich, using the Rpi-vnt1.1 gene isolated from a wild relative of potato, Solanum venturii, and introduced by GM methods into the potato variety Desiree. PMID:24535396

Jones, Jonathan D G; Witek, Kamil; Verweij, Walter; Jupe, Florian; Cooke, David; Dorling, Stephen; Tomlinson, Laurence; Smoker, Matthew; Perkins, Sara; Foster, Simon

2014-04-01

499

Crushed salt reconsolidation at elevated temperatures.  

SciTech Connect

There is a long history of testing crushed salt as backfill for the Waste Isolation Pilot Plant program, but testing was typically done at 100 C or less. Future applications may involve backfilling crushed salt around heat-generating waste packages, where near-field temperatures could reach 250 C or hotter. A series of experiments were conducted to investigate the effects of hydrostatic stress on run-of-mine salt at temperatures up to 250 C and pressures to 20 MPa. The results of these tests were compared with analogous modeling results. By comparing the modeling results at elevated temperatures to the experimental results, the adequacy of the current crushed salt reconsolidation model was evaluated. The model and experimental results both show an increase in the reconsolidation rate with temperature. The current crushed salt model predicts the experimental results well at a temperature of 100 C and matches the overall trends, but over-predicts the temperature dependence of the reconsolidation. Further development of the deformation mechanism activation energies would lea