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1

Changes in context and perception of maximum reaching height.  

PubMed

Successfully performing a given behavior requires flexibility in both perception and behavior. In particular, doing so requires perceiving whether that behavior is possible across the variety of contexts in which it might be performed. Three experiments investigated how (changes in) context (ie point of observation and intended reaching task) influenced perception of maximum reaching height. The results of experiment 1 showed that perceived maximum reaching height more closely reflected actual reaching ability when perceivers occupied a point of observation that was compatible with that required for the reaching task. The results of experiments 2 and 3 showed that practice perceiving maximum reaching height from a given point of observation improved perception of maximum reaching height from a different point of observation, regardless of whether such practice occurred at a compatible or incompatible point of observation. In general, such findings show bounded flexibility in perception of affordances and are thus consistent with a description of perceptual systems as smart perceptual devices. PMID:24919349

Wagman, Jeffrey B; Day, Brian M

2014-01-01

2

Nested prospectivity in perception: Perceived maximum reaching height reflects anticipated changes in reaching ability  

Microsoft Academic Search

Perception of possibilities for behavior is a necessarily prospective (i.e., forward-looking) act. Such prospectivity is highlighted\\u000a by the fact that, in general, behaviors are nested within behaviors over a number of spatial and temporal scales. Participants\\u000a reported their maximum vertical reaching height when they expected to walk across the room and (1) reach for an object while\\u000a standing on the

Jeffrey B. Wagman; Lydia L. Morgan

2010-01-01

3

Have We Reached a Maximum Astronomical Research Output?  

NASA Astrophysics Data System (ADS)

The US astronomical research output during the past 50 yr has been growing at 6 times the population increase and we wonder whether that ratio can continue. I counted pages of the AJ and ApJ for the past 50 yr, and corrected them for changes in format, foreign input, online contributions, and population increases. For the combined two journals, the American astronomical output is still increasing at a current 128 pages per million people. The same is true for UK contributions to the MNRAS, except that those lag behind the US by 10 yr. For Europe I did not want to dilute the contributions in A&A from the major producers with those of the countries still developing major astronomical centers. Therefore I counted pages for France, Germany, Italy, and the Netherlands (FGIN) only. However, Europeans still publish many of their articles in MNRAS, in particular, and ApJ. Counting FGIN articles in all four journals showed a steady rise but with a 12 yr lag behind the US. We conclude that the astronomical research rates in all three regions have not yet reached a maximum.

Abt, Helmut A.

2010-08-01

4

Maximum Fruit Growth Potential Following Resource Limitation During Peach Growth  

Microsoft Academic Search

To achieve its maximum organ growth potential, an organ must grow at its potential relative growth rate (RGR) throughout development. When resource availability limits growth, the RGR is reduced below the potential RGR. This study examines whether, following a period of resource-limited growth, the RGR is able to increase to the potential RGR when sufficient resources are available. Fruit RGRs

Yaffa L. Grossman; Theodore M. DeJong

1995-01-01

5

Model-based neural decoding of reaching movements: a maximum likelihood approach.  

PubMed

A new paradigm for decoding reaching movements from the signals of an ensemble of individual neurons is presented. This new method not only provides a novel theoretical basis for the task, but also results in a significant decrease in the error of reconstructed hand trajectories. By using a model of movement as a foundation for the decoding system, we show that the number of neurons required for reconstruction of the trajectories of point-to-point reaching movements in two dimensions can be halved. Additionally, using the presented framework, other forms of neural information, specifically neural "plan" activity, can be integrated into the trajectory decoding process. The decoding paradigm presented is tested in simulation using a database of experimentally gathered center-out reaches and corresponding neural data generated from synthetic models. PMID:15188860

Kemere, Caleb; Shenoy, Krishna V; Meng, Teresa H

2004-06-01

6

The effects of box size, frequency and extended horizontal reach on maximum acceptable weights of lifting  

Microsoft Academic Search

In the development of our present manual materials handling (MMH) guidelines (Ergonomics 34 (1991) 1197), the assumption was made that the effects of frequency on maximum acceptable weights (MAWs) of lifting with a large box (hand distance, 38cm from chest) were similar to frequency effects on MAWs of lifting with a small box (hand distance, 17cm from chest). The first

Vincent M. Ciriello

2003-01-01

7

Forbearance for fluoxetine: Do monoaminergic antidepressants require a number of years to reach maximum therapeutic effect in humans?  

PubMed

It is of high clinical interest to better understand the timecourse through which psychiatric drugs produce their beneficial effects. While a rough estimate of the time lag between initiating monoaminergic antidepressant therapy and the onset of therapeutic effect in depressed subjects is two weeks, much less is known about when these drugs reach maximum effect. This paper briefly examines studies that directly address this question through long-term antidepressant administration to humans, while also putting forth a simple theoretical approach for estimating the time required for monoaminergic antidepressants to reach maximum therapeutic effect in humans. The theory invokes a comparison between speed of antidepressant drug response in humans and in rodents, focusing on the apparently greater speed in rodents. The principal argument is one of proportions, comparing earliest effects of these drugs in rodents and humans, versus their time to reach maximum effect in these organisms. If the proportionality hypothesis is even coarsely accurate, then applying these values or to some degree their ranges to the hypothesis, may suggest that monoaminergic antidepressants require a number of years to reach maximum effect in humans, at least in some individuals. PMID:24131223

Fitzgerald, Paul J

2014-07-01

8

Impact of various noises on maximum reach in broadband light source based high-capacity WDM passive optical networks.  

PubMed

We investigated the effects of various noises on the performance of extended-reach WDM-PONs based on broadband light sources (BLSs). The maximum reach in BLS based WDM-PONs was analyzed by taking into account the impact of relative intensity noise of optical source, chromatic dispersion of transmission fiber and in-band crosstalk. We confirmed that the system's performance of BLS based WDM-PONs would be strongly dependent on the equivalent optical bandwidth of optical source. From the results, we found that the maximum reach in BLS based WDM-PONs operating at 1.25 Gb/s could be increased to be approximately 70 km of single-mode fiber as long as the chirp and relative intensity noise (RIN) of optical source would be suppressed properly. PMID:20588835

Kim, Chul Han

2010-05-10

9

Occurrence and Impact of Insects in Maximum Growth Plantations  

SciTech Connect

Investigation of the relationships between intensive management practices and insect infestation using maximum growth potential studies of loblolly pine constructed over five years using a hierarchy of cultural treatments-monitoring differences in growth and insect infestation levels related to the increasing management intensities. This study shows that tree fertilization can increase coneworm infestation and demonstrated that tip moth management tree growth, at least initially.

Nowak, J.T.; Berisford, C.W.

2001-01-01

10

Maximum Fruit Growth Potential and Seasonal Patterns of Resource Dynamics During Peach Growth  

Microsoft Academic Search

Maximum fruit growth potential, the growth attained by fruits when they are grown under optimal environmental conditions in the presence of a non-limiting supply of resources, was estimated for two peach [Prunus persica (L.) Batsch] cultivars that differ in the timing of resource demand for reproductive growth. Maximum potential fruit growth was estimated on trees that were heavily thinned at

Yaffa L. Grossman; Theodore M. DeJong

1995-01-01

11

Maximum Vegetative Growth Potential and Seasonal Patterns of Resource Dynamics during Peach Growth  

Microsoft Academic Search

The maximum vegetative growth potential of two peach [Prunus persica (L.) Batsch] cultivars that differ in the timing of resource demand for reproductive growth was determined in terms of stem extension, stem and leaf dry weight accumulation, and trunk radial increment on defruited trees. The maximum vegetative growth potentials were similar on the two cultivars indicating that the greater partitioning

Yaffa L. Grossman; Theodore M. Dejong

1995-01-01

12

The vermetid gastropod Dendropoma maximum reduces coral growth and survival  

PubMed Central

Coral reefs are one of the most diverse systems on the planet; yet, only a small fraction of coral reef species have attracted scientific study. Here, we document strong deleterious effects of an often overlooked species—the vermetid gastropod, Dendropoma maximum—on growth and survival of reef-building corals. Our surveys of vermetids on Moorea (French Polynesia) revealed a negative correlation between the density of vermetids and the per cent cover of live coral. Furthermore, the incidence of flattened coral growth forms was associated with the presence of vermetids. We transplanted and followed the fates of focal colonies of four species of corals on natural reefs where we also manipulated presence/absence of vermetids. Vermetids reduced skeletal growth of focal corals by up to 81 per cent and survival by up to 52 per cent. Susceptibility to vermetids varied among coral species, suggesting that vermetids could shift coral community composition. Our work highlights the potential importance of a poorly studied gastropod to coral dynamics.

Shima, Jeffrey S.; Osenberg, Craig W.; Stier, Adrian C.

2010-01-01

13

Allometries of Maximum Growth Rate versus Body Mass at Maximum Growth Indicate That Non-Avian Dinosaurs Had Growth Rates Typical of Fast Growing Ectothermic Sauropsids  

PubMed Central

We tested if growth rates of recent taxa are unequivocally separated between endotherms and ectotherms, and compared these to dinosaurian growth rates. We therefore performed linear regression analyses on the log-transformed maximum growth rate against log-transformed body mass at maximum growth for extant altricial birds, precocial birds, eutherians, marsupials, reptiles, fishes and dinosaurs. Regression models of precocial birds (and fishes) strongly differed from Case’s study (1978), which is often used to compare dinosaurian growth rates to those of extant vertebrates. For all taxonomic groups, the slope of 0.75 expected from the Metabolic Theory of Ecology was statistically supported. To compare growth rates between taxonomic groups we therefore used regressions with this fixed slope and group-specific intercepts. On average, maximum growth rates of ectotherms were about 10 (reptiles) to 20 (fishes) times (in comparison to mammals) or even 45 (reptiles) to 100 (fishes) times (in comparison to birds) lower than in endotherms. While on average all taxa were clearly separated from each other, individual growth rates overlapped between several taxa and even between endotherms and ectotherms. Dinosaurs had growth rates intermediate between similar sized/scaled-up reptiles and mammals, but a much lower rate than scaled-up birds. All dinosaurian growth rates were within the range of extant reptiles and mammals, and were lower than those of birds. Under the assumption that growth rate and metabolic rate are indeed linked, our results suggest two alternative interpretations. Compared to other sauropsids, the growth rates of studied dinosaurs clearly indicate that they had an ectothermic rather than an endothermic metabolic rate. Compared to other vertebrate growth rates, the overall high variability in growth rates of extant groups and the high overlap between individual growth rates of endothermic and ectothermic extant species make it impossible to rule out either of the two thermoregulation strategies for studied dinosaurs.

Werner, Jan; Griebeler, Eva Maria

2014-01-01

14

Allometries of maximum growth rate versus body mass at maximum growth indicate that non-avian dinosaurs had growth rates typical of fast growing ectothermic sauropsids.  

PubMed

We tested if growth rates of recent taxa are unequivocally separated between endotherms and ectotherms, and compared these to dinosaurian growth rates. We therefore performed linear regression analyses on the log-transformed maximum growth rate against log-transformed body mass at maximum growth for extant altricial birds, precocial birds, eutherians, marsupials, reptiles, fishes and dinosaurs. Regression models of precocial birds (and fishes) strongly differed from Case's study (1978), which is often used to compare dinosaurian growth rates to those of extant vertebrates. For all taxonomic groups, the slope of 0.75 expected from the Metabolic Theory of Ecology was statistically supported. To compare growth rates between taxonomic groups we therefore used regressions with this fixed slope and group-specific intercepts. On average, maximum growth rates of ectotherms were about 10 (reptiles) to 20 (fishes) times (in comparison to mammals) or even 45 (reptiles) to 100 (fishes) times (in comparison to birds) lower than in endotherms. While on average all taxa were clearly separated from each other, individual growth rates overlapped between several taxa and even between endotherms and ectotherms. Dinosaurs had growth rates intermediate between similar sized/scaled-up reptiles and mammals, but a much lower rate than scaled-up birds. All dinosaurian growth rates were within the range of extant reptiles and mammals, and were lower than those of birds. Under the assumption that growth rate and metabolic rate are indeed linked, our results suggest two alternative interpretations. Compared to other sauropsids, the growth rates of studied dinosaurs clearly indicate that they had an ectothermic rather than an endothermic metabolic rate. Compared to other vertebrate growth rates, the overall high variability in growth rates of extant groups and the high overlap between individual growth rates of endothermic and ectothermic extant species make it impossible to rule out either of the two thermoregulation strategies for studied dinosaurs. PMID:24586409

Werner, Jan; Griebeler, Eva Maria

2014-01-01

15

The effects of container size, frequency and extended horizontal reach on maximum acceptable weights of lifting for female industrial workers  

Microsoft Academic Search

In the development of our present manual materials handling (MMH) guidelines (Snook, S.H., Ciriello, V.M., 1991. The design of manual tasks: revised tables of maximum acceptable weights and forces. Ergonomics 34, 1197–1213), the assumption was made that the effects of frequency on maximum acceptable weights (MAWs) of lifting with a large box (hand distance, 38cm from chest) were similar to

Vincent M. Ciriello

2007-01-01

16

"To change the world." Cairo conference reaches consensus on plan to stabilize world growth by 2015.  

PubMed

After 6 days of debate and 200 speakers during September 5-13, 1994, participants from 180 countries at the Cairo International Conference on Population and Development (ICPD) agreed on a strategy for curbing global population growth over the next 20 years. The objective was sustained economic growth and sustainable development. In his opening remarks, UN Secretary-General Boutros Boutros-Ghali said that the objective was to balance humanity and the environment with the means to sustain life, and that the efficacy of the world economic order depended to some extent on the ICPD. Participants were urged to use rigor, tolerance, and conscience in conference deliberations. Men and women should have the right and the means to choose their families' futures. The preamble stated that the ICPD would probably be the last opportunity in the twentieth century to address globally the issues relating to population and development. UN Population Fund Executive Director Nafis Sadik remarked that the ICPD had the potential to change the world. Egyptian President Mohamed Hosni Mubarak was elected president of the ICPD. Mubarak stated that solutions to population problems must go beyond demographic accounting and incorporate change in social, economic, and cultural conditions. Norway's Prime Minister Gro Harlem Brundtland stated that development in many countries never reached many women. She called it a hypocritical morality that allowed women to suffer and die from unwanted pregnancies, illegal abortions, and miserable living conditions. US Vice President Albert Gore called for comprehensive and holistic solutions. The essential features of social change would involve democracy, economic reform, low rates of inflation, low levels of corruption, sound environmental management, free and open markets, and access to developed country markets. Pakistan's Prime Minister Benazir urged the empowerment of women. Many expressed the concern about unsustainable consumption in industrialized countries. Prior world population conferences had been held in Rome (1954), Belgrade (1965), Bucharest (1974), and Mexico City (1984). The first World Plan of Action was adopted in 1974 and changed at the 1984 conference. PMID:12288776

1994-12-01

17

Inhibition of the maximum specific growth and fermentation rate of Zymomonas mobilis by ethanol  

Microsoft Academic Search

The inhibition of the maximum specific growth and fermentation rate of Zymomonas mobilis by ethanol was studied in turbidostat cultures at constant and stepwise changed ethanol concentrations. Up to 50 g\\/l ethanol, the inhibition kinetics can be approximated by a linear relationship between the specific growth rate and the ethanol concentration. Above this level, deviations from this linearity are observed.

I. M. L. Joebses; J. A. Roels

1986-01-01

18

Maximum photosynthetic efficiency of biomass growth: a criticism of some measurements  

SciTech Connect

The yield of biomass produced in a photosynthetic culture is an expression of the photosynthetic efficiency. Microbial cells consume energy for both growth and for maintenance. The bioenergetics of Chlorella cultures and the maximum growth yields obtained by various researchers are examined in this paper.

Lee, Y.K.; Pirt, S.J.

1982-02-01

19

Inhibition of the maximum specific growth and fermentation rate of Zymomonas mobilis by ethanol  

SciTech Connect

The inhibition of the maximum specific growth and fermentation rate of Zymomonas mobilis by ethanol was studied in turbidostat cultures at constant and stepwise changed ethanol concentrations. Up to 50 g/l ethanol, the inhibition kinetics can be approximated by a linear relationship between the specific growth rate and the ethanol concentration. Above this level, deviations from this linearity are observed. The specific fermentation rates were less inhibited by ethanol than was the specific growth rate. The maximum ethanol concentration achieved was 72 g/l. The response time for the adaptation of a turbidostat culture to step changes in the ethanol concentration was markedly dependent on the concentration level, the response time being larger at high ethanol concentrations. 44 references.

Joebses, I.M.L.; Roels, J.A.

1986-04-01

20

Vortices, maximum growth and the problem of finite-time singularity formation  

NASA Astrophysics Data System (ADS)

In this work we are interested in extreme vortex states leading to the maximum possible growth of palinstrophy in 2D viscous incompressible flows on periodic domains. This study is a part of a broader research effort motivated by the question about the finite-time singularity formation in the 3D Navier–Stokes system and aims at a systematic identification of the most singular flow behaviors. We extend the results reported in Ayala and Protas (2014 J. Fluid Mech. 742 340–67) where extreme vortex states were found leading to the growth of palinstrophy, both instantaneously and in finite time, which saturates the estimates obtained with rigorous methods of mathematical analysis. Here we uncover the vortex dynamics mechanisms responsible for such extreme behavior in time-dependent 2D flows. While the maximum palinstrophy growth is achieved at short times, the corresponding long-time evolution is characterized by some nontrivial features, such as vortex scattering events.

Ayala, Diego; Protas, Bartosz

2014-06-01

21

Expanding the reach of youth mentoring: partnering with youth for personal growth and social change.  

PubMed

The goals of youth mentoring have broadened from redressing youth problems to promoting positive youth development. Yet, many of the principles associated with contemporary conceptualizations of development found in the positive youth development (PYD) and community psychology (CP) literature have yet to be fully integrated into mentoring research and practice. These approaches place greater emphasis on youth as assets to their communities and the promotion of positive development through the cultivation of these assets, often by fostering collaborative partnerships between youth and adults to effect social change. In this paper, we examine how bringing these systemic, asset-oriented approaches more fully to bear on the youth mentoring process creates opportunities that may both extend the reach and deepen the impact of youth mentoring through the promotion of community, social, and individual change. PMID:23267749

Liang, Belle; Spencer, Renée; West, Jennifer; Rappaport, Nancy

2013-04-01

22

Auxin transport is sufficient to generate a maximum and gradient guiding root growth.  

PubMed

The plant growth regulator auxin controls cell identity, cell division and cell expansion. Auxin efflux facilitators (PINs) are associated with auxin maxima in distal regions of both shoots and roots. Here we model diffusion and PIN-facilitated auxin transport in and across cells within a structured root layout. In our model, the stable accumulation of auxin in a distal maximum emerges from the auxin flux pattern. We have experimentally tested model predictions of robustness and self-organization. Our model explains pattern formation and morphogenesis at timescales from seconds to weeks, and can be understood by conceptualizing the root as an 'auxin capacitor'. A robust auxin gradient associated with the maximum, in combination with separable roles of auxin in cell division and cell expansion, is able to explain the formation, maintenance and growth of sharply bounded meristematic and elongation zones. Directional permeability and diffusion can fully account for stable auxin maxima and gradients that can instruct morphogenesis. PMID:17960234

Grieneisen, Verônica A; Xu, Jian; Marée, Athanasius F M; Hogeweg, Paulien; Scheres, Ben

2007-10-25

23

Maximum Shell Size, Growth Rate, and Maturation Age Correlate With Longevity in Bivalve Molluscs  

PubMed Central

Bivalve molluscs are newly discovered models of successful aging, and this invertebrate group includes Arctica islandica, with the longest metazoan life span. Despite an increasing biogerontological focus on bivalves, their life history traits in relation to maximum age are not as comprehensively understood as those in vertebrate model aging organisms. We explore the allometric scaling of longevity and the relationship between development schedules (time to maturity and growth rate) and longevity in the Bivalvia. Using a traditional nonphylogenetic approach and the phylogenetically independent contrasts method, the relationship among these life history parameters is analyzed. It is demonstrated that in bivalves, maximum shell size, development, and growth rates all associate with longevity. Our findings support the observations of life history patterns in mammals and fish. This is the first investigation into the relationship among longevity, size, and development schedules throughout this group, and the results strengthened by the control for phylogenetic independence.

Richardson, C. A.; Austad, S. N.

2011-01-01

24

Total maximum daily load (TMDL) based sustainable basin growth and management strategy.  

PubMed

This study focused on the development and application of the new approach 'Total Maximum Daily Load (TMDL) based sustainable basin growth and management strategy' to give better insight for the management of surface waters. The establishment of the proposed decision process mainly comprised: beneficial use designations-targets, interrogation of the ambient water quality, selection of variable(s) for TMDL analysis, water quality modeling, basin growth scenarios development and decision on the basin growth plan. The approach was validated through a systematic application study in a field case in Turkey, known as Tahtali Basin. Results revealed that decision process assists policy makers to develop realistic strategies that take into account the basin specific conditions. PMID:18157610

Boyacioglu, Hülya; Alpaslan, M Necdet

2008-11-01

25

Growth, yield and photosynthesis of Panicum maximum and Stylosanthes hamata under elevated CO2.  

PubMed

Plant height, biomass production, assimilatory functions and chlorophyll accumulation of Panicum maximum and Stylosanthes hamata in intercropping systems was influenced significantly under elevated CO2 (600 +/- 50 ppm) in open top chambers (OTCs). The plant height increased by 32.0 and 49.0% over the control in P. maximum and S. hamata respectively in intercropping system under elevated CO2 over open field grown crops (Ca). P. maximum and S. hamata produced 67 and 85% higher fresh and dry biomass respectively under elevated CO2. Rates of photosynthesis and stomatal conductance increased in both the crop species in intercropping systems under elevated CO2. The canopy photosynthesis (photosynthesis x leaf area index) of these crop species increased significantly under elevated CO2 over the open grown crops. The chlorophyll a and b accumulation were also higher in the leaves of both the crop species as grown in OTC with elevated CO2. The increased chlorophyll content, leaf area index and canopy photosynthesis led to higher growth and biomass production in these crop species under elevated CO2. The total carbon sequestration in crop biomass and soils during the three years was 21.53 Mg C/ha under elevated CO2. The data revealed that P. maximum and S. hamata intercropping system is the potential as a sink for the increasing level of CO2 in the atmosphere in the semi-arid tropics. PMID:21186734

Bhatt, R K; Baig, M J; Tiwari, H S; Roy, Sharmila

2010-07-01

26

The Time of Maximum Post-Ischemic Hyperperfusion Indicates Infarct Growth Following Transient Experimental Ischemia  

PubMed Central

After recanalization, cerebral blood flow (CBF) can increase above baseline in cerebral ischemia. However, the significance of post-ischemic hyperperfusion for tissue recovery remains unclear. To analyze the course of post-ischemic hyperperfusion and its impact on vascular function, we used magnetic resonance imaging (MRI) with pulsed arterial spin labeling (pASL) and measured CBF quantitatively during and after a 60 minute transient middle cerebral artery occlusion (MCAO) in adult rats. We added a 5% CO2 - challenge to analyze vasoreactivity in the same animals. Results from MRI were compared to histological correlates of angiogenesis. We found that CBF in the ischemic area recovered within one day and reached values significantly above contralateral thereafter. The extent of hyperperfusion changed over time, which was related to final infarct size: early (day 1) maximal hyperperfusion was associated with smaller lesions, whereas a later (day 4) maximum indicated large lesions. Furthermore, after initial vasoparalysis within the ischemic area, vasoreactivity on day 14 was above baseline in a fraction of animals, along with a higher density of blood vessels in the ischemic border zone. These data provide further evidence that late post-ischemic hyperperfusion is a sequel of ischemic damage in regions that are likely to undergo infarction. However, it is transient and its resolution coincides with re-gaining of vascular structure and function.

Wegener, Susanne; Artmann, Judith; Luft, Andreas R.; Buxton, Richard B.; Weller, Michael; Wong, Eric C.

2013-01-01

27

Significance of river-aquifer interactions for reach-scale thermal patterns and trout growth potential in the Motueka River, New Zealand  

NASA Astrophysics Data System (ADS)

To assess whether reaches of the Motueka River (New Zealand) that gain water from groundwater were likely to represent significant cold-water refugia for brown trout during periods of high water temperatures, water temperature was monitored for more than 18 months in two gaining reaches of the Motueka River and three reaches that were predicted to be losing water to groundwater. These data were used to predict brown trout ( Salmo trutta) growth in gaining and losing reaches. Groundwater inputs had a small effect on water temperature at the reach-scale and modelling suggests that the differences observed were unlikely to result in appreciable differences in trout growth. Several coldwater patches were identified within the study reach that were up to 3.5°C cooler than the mainstem, but these were generally shallow and were unlikely to provide refuge for adult trout. The exception was Hinetai Spring, which had a mean water temperature of close to 16°C during the period January-March, when temperatures in the mainstem regularly exceeded 19°C. Trout were observed within the cold-water plume at the mouth of Hinetai Stream, which would allow them to thermoregulate when mainstem temperatures are unfavourable while still being able to capitalise on food resources available in the mainstem.

Olsen, Dean A.; Young, Roger G.

2009-02-01

28

A comparison of least squares and conditional maximum likelihood estimators under volume endpoint censoring in tumor growth experiments.  

PubMed

Measurements in tumor growth experiments are stopped once the tumor volume exceeds a preset threshold: a mechanism we term volume endpoint censoring. We argue that this type of censoring is informative. Further, least squares (LS) parameter estimates are shown to suffer a bias in a general parametric model for tumor growth with an independent and identically distributed measurement error, both theoretically and in simulation experiments. In a linear growth model, the magnitude of bias in the LS growth rate estimate increases with the growth rate and the standard deviation of measurement error. We propose a conditional maximum likelihood estimation procedure, which is shown both theoretically and in simulation experiments to yield approximately unbiased parameter estimates in linear and quadratic growth models. Both LS and maximum likelihood estimators have similar variance characteristics. In simulation studies, these properties appear to extend to the case of moderately dependent measurement error. The methodology is illustrated by application to a tumor growth study for an ovarian cancer cell line. PMID:22826185

Roy Choudhury, Kingshuk; O'Sullivan, Finbarr; Kasman, Ian; Plowman, Greg D

2012-12-20

29

Defining an Urban Growth Strategy Which will Achieve Maximum Travel Demand Reduction and Access Opportunity Enhancement.  

National Technical Information Service (NTIS)

This report investigated the potential for directing the growth of an urban region so that the evolving urban form contributes to high levels of access opportunity with minimum travel requirements. Measures of total travel, accessibility, and spatial equi...

J. W. Clark

1974-01-01

30

Effect of maximum Cu ratio during three-stage CIGS growth documented by design of experiment  

Microsoft Academic Search

The impact of a Cu-rich growth period during three-stage CIGS co-evaporation on device performance was examined. Design of experiments was utilized to determine effect magnitudes and statistical significance. It was found that a Cu-rich growth period yields a statistically significant benefit for device performance. By varying film thickness, the number of moles deposited in stage 3 was also included as

L. L. Repins; D. C. Fisher; M. E. Beck; J. S. Britt

2005-01-01

31

Effects of the herbicide bentazon on growth and photosystem II maximum quantum yield of the marine diatom Skeletonema costatum  

Microsoft Academic Search

Chlorophyll fluorescence techniques are used for the detection of toxic substances in samples of photosynthetic cells by measuring chlorophyll a fluorimetric parameters, which are a response of the PSII physiological status. This work was conducted to determine the effects of the herbicide bentazon (CASRN 25057-89-0) on growth and maximum quantum yield of photosystem II (Fv\\/Fm) in cells of the marine

R. S. Macedo; A. T. Lombardi; C. Y. Omachi; L. R. Rörig

2008-01-01

32

Operation of suspended-growth shortcut biological nitrogen removal (SSBNR) based on the minimum\\/maximum substrate concentration  

Microsoft Academic Search

This study exploited the concept of the minimum\\/maximum substrate concentrations (MSC values) for identifying proper start-up conditions and achieving stable and low effluent total ammonium nitrogen (TAN) concentrations in suspended-growth short-cut biological nitrogen removal (SSBNR). Calculations based on the MSC concept indicated that SDmax, the TAN concentration above which ammonium-oxidizing bacteria (AOB) are washed out, was around 450mgTAN\\/L at the

Wookeun Bae; Bruce E. Rittmann; Seungjin Kim; Jinwook Chung

2010-01-01

33

Maximum aerobic power and body composition during the puberty growth period: similarities and differences between children of two European countries.  

PubMed

This report gives results of a longitudinal study of two cohorts of school children in Norway and West-Germany. The rate of growth in body size and composition is identical for the two samples, but different for the two sexes, and follows closely the trend of growth which has been found for North-Europeans in general. Despite of this similarity in growth of anatomical variables the Norwegian children appeared to be superior in their maximum aerobic power at all comparable ages and in both sexes. The differences between means in maximal oxygen uptake varies somewhat with age and sex and are in the range of 5-10%. It is suggested that the mean differences between Norwegian and German children in their exercise and cardio-vascular fitness are brought about by a more physically active behavioural pattern of living in Norway. PMID:7227388

Rutenfranz, J; Andersen, K L; Seliger, V; Klimmer, F; Berndt, I; Ruppel, M

1981-05-01

34

Effects of the herbicide bentazon on growth and photosystem II maximum quantum yield of the marine diatom Skeletonema costatum.  

PubMed

Chlorophyll fluorescence techniques are used for the detection of toxic substances in samples of photosynthetic cells by measuring chlorophyll a fluorimetric parameters, which are a response of the PSII physiological status. This work was conducted to determine the effects of the herbicide bentazon (CASRN 25057-89-0) on growth and maximum quantum yield of photosystem II (Fv/Fm) in cells of the marine diatom Skeletonema costatum. Unialgal cultures were exposed to several bentazon concentrations and its effects on algal growth and Fv/Fm were determined. The traditional algal growth inhibition test (algal biomass measurements) and DCMU-induced chlorophyll a variable fluorescence measurements were determined. Our results showed that even low concentrations of bentazon rapidly lead to Fv/Fm decrease, while the effects on algal growth were detected after 24 h of exposure. The LOEC (2.81 mg L(-1)) and EC50 (13.0 mg L(-1)) determined through Fv/Fm experiments were lower than the LOEC (22.5 mg L(-1)) and EC50 (24.0 mg L(-1)) determined through algal growth inhibition experiments. This confirms that the Fv/Fm is a more sensitive parameter than algal growth for monitoring the effects of bentazon. The present results have demonstrated the applicability of Fv/Fm parameter to access the early toxicity of bentazon, as well as other PSII-inhibition compounds, before significant changes occurred in the original concentration and bioavailability of these toxicants during longer exposure times. PMID:18180139

Macedo, R S; Lombardi, A T; Omachi, C Y; Rörig, L R

2008-04-01

35

A simple approximate result for the maximum growth rate of baroclinic instabilities  

NASA Technical Reports Server (NTRS)

The Charney problem for baroclinic instability involves the quasi-geostrophic instability of a zonal flow on a beta plane where the zonal flow is characterized by a constant vertical shear. The atmosphere is non-Boussinesq and continuous. The solution of this problem involves confluent hypergeometric functions, and the mathematical difficulty of the problem has precluded extracting simple results of generality. It is shown that there exists very simple, powerful approximate result for the growth rate of the most rapidly growing instability, viz., that this growth rate is linearly proportional to the surface meridional temperature gradient. The coefficient of proportionality is also easily determined. The result extends to substantially more general profiles than those in the Charney problem.

Lindzen, R. S.; Farrell, B.

1980-01-01

36

Physiological and growth responses of C3 and C4 plants at the Pleistocene glacial maximum  

SciTech Connect

A C3 plant (Abutilon theophrasti) and a C4 plant (Amaranthus retroflexus) were grown from seed in the Duke University Phytotron under four CO2 concentrations (15 Pa, below the Pleistocene minimum), 27 Pa (pre-industrial), 35 Pa (current), and 70 Pa (future) to examine photosynthetic, growth and reproduction responses of annual plants to historic and future levels of CO2. Net photosynthesis and growth were greatly inhibited at 15 Pa and greatly stimulated at 70 Pa. in the C3 Abutilon but only slightly affected in the C4 Amaranthus. Flower bud initiation was not affected by CO2 treatment in either species but all flower buds in 15 Pa CO2 aborted in the C3 within two days of appearance while no inhibition of reproduction was observed at low CO2 in the C4. Differences in physiology, growth and reproduction to the low levels of atmospheric CO2 of the Pleistocene suggest that competitive interactions of C3 and C4 annuals have changed through geologic time. A major question concerning the survival and evolution of obligate C3 annuals during the CO2 minima of the Pleistocene is raised by the results of this study.

Strain, B.R. [Duke Univ., Durham, NC (United States)

1995-06-01

37

Reaching the hard to reach.  

PubMed

The 1994 International Conference on Population and Development proposed increasing contraceptive couple protection from 550 million in 1995 to 880 million in 2015. The task for family planning (FP) programs is to provide access to services for, sometimes, inaccessible rural populations. FP need based on desire for no more children has ranged from under 20% in Senegal to almost 80% in Peru. Socioeconomic development was found not to be a prerequisite for fertility change. Gender inequalities in education and social autonomy must be changed. FP access is very important among women with a disadvantaged background or among women unsure about FP. Bangladesh is a good example of a country with increased contraceptive prevalence despite low income. The rule of thumb is that contraception increases of 15% contribute to a drop in family size of about one child. Program effectiveness is related to a variety of factors: contraceptive availability at many locations, acceptable price of contraception, delivery of the oral contraceptives without prescriptions, and other strategies. FP is a service not a medical treatment. A range of methods must be promoted and available from a range of facilities. Contraceptive use is dependent on the woman's stage in her lifecycle and is dependent on informed choice. Community-based distribution systems are effective, whereas free distribution by poorly-trained field workers is not always very effective because patient payment of all or part of the cost assures quality and freedom of choice. Effective programs for underprivileged groups involve aggressive, easy to manage programs that can be replicated rapidly. FP serves a useful function in depressing maternal mortality among the poor in Africa, who have no access to quality health services. Social marketing is an effective strategy for reaching remote areas. Political will and robust management are necessary commodities. PMID:12345832

Bhiwandi, P; Campbell, M; Potts, M

1994-01-01

38

Effect of carbon substrate on electron acceptor diauxic lag and anoxic maximum specific growth rate in species with and without periplasmic enzyme  

Microsoft Academic Search

The effect of oxidation state of carbon substrate on the diauxic lag of facultative anaerobic denitrifying bacteria growing aerobically upon switching to anoxic growth was studied. Also studied was the effect on the anoxic maximum specific growth rate. Two pure bacteria cultures were used, Paracoccus pantotrophus, denitrifying bacteria containing a periplasmic nitrate reductase (Nap), and Pseudomonas denitrificans, denitrifying bacteria lacking

Anna I. Casasús; Dong-Uk Lee; Ryan K. Hamilton; Spyros A. Svoronos; Ben Koopman

2007-01-01

39

Interannual physiological and growth responses of glacial Juniperus to changes in atmospheric [CO2] since the Last Glacial Maximum  

NASA Astrophysics Data System (ADS)

During the Last Glacial Maximum, atmospheric [CO2] was as low as 180 ppm and has currently risen to a modern value of 393 ppm as a result of fossil fuel combustion and deforestation. In order to understand how changing [CO2] influenced trees over the last 50,000 years, we analyzed carbon isotope ratios and width of individual tree rings from glacial Juniperus specimens preserved in the Rancho La Brea tar pits in southern California (aged 14-49 kyr BP). Modern trees were also analyzed to compare effects of changing precipitation, temperature and atmospheric [CO2] on physiology and growth. To assess physiological responses, we calculated ci/ca (intercellular [CO2]/atmospheric [CO2]) for each annual ring of each tree. This ratio incorporates numerous aspects of plant physiology, including stomatal conductance and photosynthetic capacity. In addition, we measured ring widths for each sample, and standardized these measurements into indices in order to compare across individuals. Mean ci/ca values remained constant throughout 50,000 years despite major environmental changes, indicating a long-term physiological set point for ci/ca in this group. Constant ci/ca ratios would be maintained through offsetting changes in stomatal conductance and photosynthetic capacity. Glacial Juniperus never experienced ci values below 90 ppm, suggesting a survival compensation point for Juniperus. In addition, glacial trees showed significantly reduced interannual variation in ci/ca, even though interannual climatic variability was as high during the LGM in this region as it is today. A lack of variability in ci/ca of glacial trees suggests that tree physiology was dominated by low [CO2], which shows low interannual variation. Modern trees showed high interannual variation in ci/ca, since water availability dominates current physiological responses and varies greatly from year to year. Interestingly, interannual variation in ring width index did not show significant differences between glacial and modern trees, suggesting these trees were adapted to maintain growth under low [CO2]. These adaptations may constrain the ability of modern trees to fully utilize increases in atmospheric [CO2]. These results have significant implications for our understanding of the adaptations of trees to changing [CO2] and indicate that the environmental factors that most strongly influence plant physiology may have changed over geologic time scales.

Gerhart, L. M.; Harris, J. M.; Ward, J. K.

2011-12-01

40

Reaching Out the Write Way.  

ERIC Educational Resources Information Center

Describes a program called "Reaching Out the Write Way" that takes place in an adult basic education literacy program at a maximum-security state prison. Describes how this innovative and low-cost program teaches inmates (many of whom are fathers) both storybook writing and bookmaking. Notes the enthusiastic responses of inmates and their…

Geraci, Pauline M.

2000-01-01

41

Effect of carbon substrate on electron acceptor diauxic lag and anoxic maximum specific growth rate in species with and without periplasmic enzyme.  

PubMed

The effect of oxidation state of carbon substrate on the diauxic lag of facultative anaerobic denitrifying bacteria growing aerobically upon switching to anoxic growth was studied. Also studied was the effect on the anoxic maximum specific growth rate. Two pure bacteria cultures were used, Paracoccus pantotrophus, denitrifying bacteria containing a periplasmic nitrate reductase (Nap), and Pseudomonas denitrificans, denitrifying bacteria lacking the periplasmic nitrate reductase. The anoxic maximum specific growth rate of both cultures following a period of aerobic growth with identical dilution up to steady-state was indeed affected by the oxidation state of the carbon, with the most oxidized substrate yielding the highest anoxic maximum specific growth rate. The diauxic lags for Paracoccus pantotrophus were considerably shorter than those for Pseudomonas denitrificans, something expected due to the presence of Nap, an enzyme not affected by aerobiosis. Since the activity of Nap in Paracoccus pantotrophus under aerobic conditions has been shown to increase with the extent of reduction of the carbon substrate, it was also expected that the diauxic lag length for these bacteria would decrease as the reduction state of the carbon substrate increased. This could not be demonstrated, as no significant lags were observed for this species. Pseudomonas denitrificans exhibited a shorter diauxic lag with the more oxidized carbon source. PMID:17129955

Casasús, Anna I; Lee, Dong-Uk; Hamilton, Ryan K; Svoronos, Spyros A; Koopman, Ben

2007-01-01

42

AEROSOL NUCLEATION AND GROWTH DURING LAMINAR TUBE FLOW: MAXIMUM SATURATIONS AND NUCLEATION RATES. (R827354C008)  

EPA Science Inventory

An approximate method of estimating the maximum saturation, the nucleation rate, and the total number nucleated per second during the laminar flow of a hot vapour–gas mixture along a tube with cold walls is described. The basis of the approach is that the temperature an...

43

Investigation of the maximum quantum yield of PS II in Haematococcus pluvialis cell cultures during growth: effects of chemical or high-intensity light treatment.  

PubMed

In this study, we investigated the increase in photosynthetic quantum yield that occurs in advance of increased microalgal growth. Haematococcus pluvialis was cultivated under normal conditions; the number of cells, the maximum quantum yield of photosystem II (F(v)/F(m)), and optical density were measured. We observed an increase in F(v)/F(m) approximately 72h prior to the cell growth phase. To confirm the relationship between photosynthetic yield and growth, samples were treated with several chemicals under high-intensity light illumination and control conditions to inhibit photosystem II and induce a decrease in the quantum photosynthetic yield. The samples were exposed to high-intensity light at an irradiance of 400?mol photonsm(-2)s(-1) for varied amount of time and were treated with chemicals such as 3-(3,4-dichlorophenyl)-1,1-dimethylurea, nigericin sodium salt and valinomycin. We observed that both the photooxidation of photosystem II reaction centers and the formation of transmembrane electrochemical gradients led to an initial decrease in fluorescence yield after the onset of high-intensity light illumination. We also observed that treatment of high-intensity light illuminated cells with antibiotics after adaptation to moderate light intensities caused a difference in photosynthetic activity. In conclusion, the maximum quantum yield of photosystem II is obtained prior to the cell growth phase and can therefore be used as a prediction parameter for cell growth. PMID:21592814

Wang, Hui-Chih; Cho, Man-Gi; Riznichenko, Galina; Rubin, Andrey B; Lee, Ji-Hyun

2011-09-01

44

Stability Conditions and Maximum Growth Rates of the Kelvin-Helmholtz Instability in a Compressible Plasma with a Density Jump.  

National Technical Information Service (NTIS)

The influence of a density jump on the stability of ideal compressible MHD Kelvin-Helmholtz modes is investigated for any orientation of B, u, and k (B is uniform). The instability with the largest growth rates are related to the torsional Alfven mode. Th...

A. G. Gonzalez J. Gratton

1994-01-01

45

Variation of Maximum Tree Height and Annual Shoot Growth of Smith Fir at Various Elevations in the Sygera Mountains, Southeastern Tibetan Plateau  

PubMed Central

Little is known about tree height and height growth (as annual shoot elongation of the apical part of vertical stems) of coniferous trees growing at various altitudes on the Tibetan Plateau, which provides a high-elevation natural platform for assessing tree growth performance in relation to future climate change. We here investigated the variation of maximum tree height and annual height increment of Smith fir (Abies georgei var. smithii) in seven forest plots (30 m×40 m) along two altitudinal transects between 3,800 m and 4,200/4,390 m above sea level (a.s.l.) in the Sygera Mountains, southeastern Tibetan Plateau. Four plots were located on north-facing slopes and three plots on southeast-facing slopes. At each site, annual shoot growth was obtained by measuring the distance between successive terminal bud scars along the main stem of 25 trees that were between 2 and 4 m high. Maximum/mean tree height and mean annual height increment of Smith fir decreased with increasing altitude up to the tree line, indicative of a stress gradient (the dominant temperature gradient) along the altitudinal transect. Above-average mean minimum summer (particularly July) temperatures affected height increment positively, whereas precipitation had no significant effect on shoot growth. The time series of annual height increments of Smith fir can be used for the reconstruction of past climate on the southeastern Tibetan Plateau. In addition, it can be expected that the rising summer temperatures observed in the recent past and anticipated for the future will enhance Smith fir's growth throughout its altitudinal distribution range.

Wang, Yafeng; Cufar, Katarina; Eckstein, Dieter; Liang, Eryuan

2012-01-01

46

Reaching Your Fitness Goals  

MedlinePLUS

Everyday Fitness Ideas from the National Institute on Aging at NIH www.nia.nih.gov/Go4Life Reaching Your Fitness ... longer, and more easily. As you increase your fitness level, you also might find that you need ...

47

REACH. Major Appliance.  

ERIC Educational Resources Information Center

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of major appliances. The instructional units focus on installation of appliances, troubleshooting washing machines, troubleshooting electric dryers,…

English, Charles; And Others

48

REACH. Heating Units.  

ERIC Educational Resources Information Center

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized units in the area of heating. The instructional units focus on electric heating systems, gas heating systems, and oil burning systems. Each unit follows a typical format that includes a unit…

Stanfield, Carter; And Others

49

Reaching for the Stars  

ERIC Educational Resources Information Center

Dr. Mae Jemison is the world's first woman astronaut of color who continues to reach for the stars. Jemison was recently successful in leading a team that has secured a $500,000 federal grant to make interstellar space travel a reality. The Dorothy Jemison Foundation for Excellence (named after Jemison's mother) was selected in June by the Defense…

Terry, Dorothy Givens

2012-01-01

50

Reaching into Pictorial Spaces  

NASA Astrophysics Data System (ADS)

While binocular viewing of 2D pictures generates an impression of 3D objects and space, viewing a picture monocularly through an aperture produces a more compelling impression of depth and the feeling that the objects are "out there", almost touchable. Here, we asked observers to actually reach into pictorial space under both binocular- and monocular-aperture viewing. Images of natural scenes were presented at different physical distances via a mirror-system and their retinal size was kept constant. Targets that observers had to reach for in physical space were marked on the image plane, but at different pictorial depths. We measured the 3D position of the index finger at the end of each reach-to-point movement. Observers found the task intuitive. Reaching responses varied as a function of both pictorial depth and physical distance. Under binocular viewing, responses were mainly modulated by the different physical distances. Instead, under monocular viewing, responses were modulated by the different pictorial depths. Importantly, individual variations over time were minor, that is, observers conformed to a consistent pictorial space. Monocular viewing of 2D pictures thus produces a compelling experience of an immersive space and tangible solid objects that can be easily explored through motor actions.

Volcic, Robert; Vishwanath, Dhanraj; Domini, Fulvio

2014-02-01

51

REACH. Refrigeration Units.  

ERIC Educational Resources Information Center

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of refrigeration. The instructional units focus on refrigeration fundamentals, tubing and pipe, refrigerants, troubleshooting, window air conditioning, and…

Snow, Rufus; And Others

52

FOSTERING MAXIMUM GROWTH IN CHILDREN.  

ERIC Educational Resources Information Center

SINCE SYMBOLS ARE SEEN AS REPRESENTATIVES OF THINGS, ACTION, RELATIONSHIPS, AND FEELINGS, YOUNG CHILDREN NEED TO LEARN TO PROCESS SYMBOLS. THE QUALITY OF A CHILD'S EDUCATION IN MANAGING AND UTILIZING SYMBOLS WILL AFFECT HIS ABILITY TO WORK, LOVE, AND GROW. SOME MAJOR IDEAS IN OUR CONCEPTUALIZATIONS OF MAN AND HIS DEVELOPMENT HAVE BEEN UPROOTED IN…

BOWER, ELI M.

53

Reaching consensus on rumors  

NASA Astrophysics Data System (ADS)

An important contribution in sociophysics is the Galam’s model of rumors spreading. This model provides an explanation of rumors spreading in a population and explains some interesting social phenomena such as the diffusion of hoaxes. In this paper the model has been reformulated as a Markov process highlighting the stochastic nature of the phenomena. This formalization allows us to derive conditions for consensus to be reached and for the existence of some interesting phenomena such as the emergence of impasses. The proposed formulation allows a deeper and more comprehensive analysis of the diffusion of rumors.

Merlone, U.; Radi, D.

2014-07-01

54

Europe reaches the Moon  

NASA Astrophysics Data System (ADS)

A complex package of tests on new technologies was successfully performed during the cruise to the Moon, while the spacecraft was getting ready for the scientific investigations which will come next. These technologies pave the way for future planetary missions. SMART-1 reached its closest point to the lunar surface so far - its first ‘perilune’ - at an altitude of about 5000 kilometres at 18:48 Central European Time (CET) on 15 November. Just hours before that, at 06:24 CET, SMART-1’s solar-electric propulsion system (or ‘ion engine’) was started up and is now being fired for the delicate manoeuvre that will stabilise the spacecraft in lunar orbit. During this crucial phase, the engine will run almost continuously for the next four days, and then for a series of shorter burns, allowing SMART-1 to reach its final operational orbit by making ever-decreasing loops around the Moon. By about mid-January, SMART-1 will be orbiting the Moon at altitudes between 300 kilometres (over the lunar south pole) and 3000 kilometres (over the lunar north pole), beginning its scientific observations. The main purpose of the first part of the SMART-1 mission, concluding with the arrival at the Moon, was to demonstrate new spacecraft technologies. In particular, the solar-electric propulsion system was tested over a long spiralling trip to the Moon of more than 84 million kilometres. This is a distance comparable to an interplanetary cruise. For the first time ever, gravity-assist manoeuvres, which use the gravitational pull of the approaching Moon, were performed by an electrically-propelled spacecraft. The success of this test is important to the prospects for future interplanetary missions using ion engines. SMART-1 has demonstrated new techniques for eventually achieving autonomous spacecraft navigation. The OBAN experiment tested navigation software on ground computers to determine the exact position and velocity of the spacecraft using images of celestial objects taken by the AMIE camera on SMART-1 as references. Once used on board future spacecraft, the technique demonstrated by OBAN will allow spacecraft to know where they are in space and how fast they are moving, limiting the need for intervention by ground control teams. SMART-1 also carried out deep-space communication tests, with the KaTE and RSIS experiments, consisting of testing radio transmissions at very high frequencies compared to traditional radio frequencies. Such transmissions will allow the transfer of ever-increasing volumes of scientific data from future spacecraft. With the Laser Link experiment, SMART-1 tested the feasibility of pointing a laser beam from Earth at a spacecraft moving at deep-space distances for future communication purposes. During the cruise, to prepare for the lunar science phase, SMART-1 made preliminary tests on four miniaturised instruments, which are being used for the first time in space: the AMIE camera, which has already imaged Earth, the Moon and two total lunar eclipses from space, the D-CIXS and XSM X-ray instruments, and the SIR infrared spectrometer. In all, SMART-1 clocked up 332 orbits around Earth. It fired its engine 289 times during the cruise phase, operating for a total of about 3700 hours. Only 59 kilograms of xenon propellant were used (out of 82 kilograms). Overall, the engine performed extremely well, enabling the spacecraft to reach the Moon two months earlier than expected. The extra fuel available also allowed the mission designers to significantly reduce the altitude of the final orbit around the Moon. This closer approach to the surface will be even more favourable for the science observations that start in January. The extra fuel will also be used to boost the spacecraft back into a stable orbit, after six months of operations around the Moon, in June, if the scientific mission is extended.

2004-11-01

55

Mexican agencies reach teenagers.  

PubMed

The Gente Joven project of the Mexican Foundation for Family Planning (MEXFAM) trains young volunteers in 19 cities to spread messages about sexually transmitted diseases and population growth to their peers. They also distribute condoms and spermicides. It also uses films and materials to spread its messages. The project would like to influence young men's behavior, but the Latin image of machismo poses a big challenge. It would like to become more responsible toward pregnancy prevention. About 50% of adolescents have sexual intercourse, but few use contraceptives resulting in a high adolescent pregnancy rate. Many of these pregnant teenagers choose not to marry. Adolescent pregnancy leads to girls leaving school, few marketable skills, and rearing children alone. Besides women who began childbearing as a teenager have 1.5 times more children than other women. Male involvement in pregnancy prevention should improve these statistics. As late as 1973, the Health Code banned promotion and sales of contraceptives, but by 1992 about 50% of women of reproductive age use contraceptives. The Center for the Orientation of Adolescents has organized 8 Young Men's Clubs in Mexico City to involve male teenagers more in family planning and to develop self-confidence. It uses a holistic approach to their development through discussions with their peers. A MEXFAM study shows that young men are not close with their fathers who tend to exude a machismo attitude, thus the young men do not have a role model for responsible sexual behavior. MEXFAM's work is cut out for them, however, since the same study indicates that 50% of the young men believe it is fine to have 1 girlfriend and 33% think women should earn more than men. A teenager volunteer reports, however, that more boys have been coming to him for contraception and information than girls in 1992 while in other years girls outnumbered the boys. PMID:12317721

Brito Lemus, R; Beamish, J

1992-08-01

56

Effects of Experimental High Flow Releases and Increased Fluctuations in Flow from Glen Canyon Dam on Abundance, Growth, and Survival Rates of Early Life Stages of Rainbow Trout in the Lee's Ferry Reach of the Colorado River  

NASA Astrophysics Data System (ADS)

The abundance of adult fish populations is controlled by the growth and survival rates of early life stages. Evaluating the effects of flow regimes on early life stages is therefore critical to determine how these regimes affect the abundance of adult populations. Experimental high flow releases from Glen Canyon Dam, primarily intended to conserve fine sediment and improve habitat conditions for native fish in the Colorado River in Grand Canyon, AZ, have been conducted in 1996, 2004, and 2008. These flows potentially affect the Lee's Ferry reach rainbow trout population, located immediately downstream of the dam, which supports a highly valued fishery and likely influences the abundance of rainbow trout in Grand Canyon. Due to concerns about negative effects of high trout abundance on endangered native fish, hourly variation in flow from Glen Canyon Dam was experimentally increased between 2003 and 2005 to reduce trout abundance. This study reports on the effects of experimental high flow releases and fluctuating flows on early life stages of rainbow trout in the Lee's Ferry reach based on monthly sampling of redds (egg nests) and the abundance and growth of age-0 trout between 2003 and 2009. Data on spawn timing, spawning elevations, and intergravel temperatures were integrated in a model to estimate the magnitude and seasonal trend in incubation mortality resulting from redd dewatering due to fluctuations in flow. Experimental fluctuations from January through March promoted spawning at higher elevations where the duration of dewatering was longer and intergravel temperatures exceeded lethal thresholds. Flow-dependent incubation mortality rates were 24% (2003) and 50% (2004) in years with higher flow fluctuations, compared to 5-11% under normal operations (2006-2009). Spatial and temporal predictions of mortality were consistent with direct observations of egg mortality determined from the excavation of 125 redds. The amount of variation in backcalculated hatch date distributions predicted by flow-independent (84-93%) and flow-dependent (82-91%) incubation loss models were similar. Age-0 abundance was generally independent of viable egg deposition, except in one year when egg deposition was 10-fold lower due to reduced spawning activity. There was no evidence from the hatch date or stock-recruitment analysis that flow-dependent incubation losses, although large in experimental years, affected the abundance of the age-0 population. The data indicate that strong compensation in survival rates shortly after emergence mitigated the impact of flow-dependent losses. Multiple lines of evidence demonstrated that the March 2008 high flow experiment (HFE) resulted in a large increase in early survival rates (fertilization to ~1-2 months from emergence) of age-0 trout due an improvement in habitat conditions. A stock-recruitment analysis indicated that age-0 abundance in July 2008 was over four-fold higher than expected given the number of viable redds that produced these fish. A hatch date analysis indicated that early survival rates were much higher for cohorts that emerged about two months after the HFE. These cohorts, which were fertilized after the HFE, were not exposed to high flows and emerged into better quality habitat. Inter annual differences in growth of age-0 trout based on otolith microstructure support this hypothesis. Growth rates in the summer and fall of 2008 (0.44 mm·day-1) were virtually the same as in 2006 (0.46 mm·day-1), the highest recorded over six years, even though abundance was eight-fold greater in 2008. I speculate that high flows in 2008 increased interstitial spaces in the substrate and food availability or quality, leading to higher early survival of recently emerged trout and better growth during summer and fall. Abundance in 2009 was over two-fold higher than expected, possibly indicating that the effect of the HFE on early life stages was somewhat persistent.

Korman, Josh

2010-05-01

57

Maximum extent of ice sheets in Morocco during the Late Ordovician glaciation  

Microsoft Academic Search

New field data demonstrate that during the Late Ordovician (Hirnantian) glaciation, an ice sheet expanding northwestwards over the Anti-Atlas range reached into the southern Meseta of northern Morocco. Its growth to a glacial maximum position resulted in extensive subglacial erosion and deformation including the development of soft-sediment striated surfaces and streamlined subglacial bedforms preserved between the High Atlas of Marrakech

Daniel Paul Le Heron; Jean-François Ghienne; Mohamed El Houicha; Yahya Khoukhi; Jean-Loup Rubino

2007-01-01

58

In-reach and out-reach programs  

NASA Technical Reports Server (NTRS)

Information is given in viewgraph form on in-reach and out-reach programs in in-space technology experiments. Information is given on thermal energy storage materials technology, industry/university in-space technology experiments, heat pipe performance, working fluid behavior, a tank pressure control experiment, spacecraft glow, the Mid-Deck Zero-Gravity Dynamics Experiment, and emulsion chamber technology.

Pyle, Jon S.

1988-01-01

59

Out of your hand's reach, out of my eyes' reach.  

PubMed

When witnessing another's action, people recruit the same motor resources that enable them to efficiently perform that action, thus gazing at its target well before the agent's hand. But just to what extent does this recruitment help people in grabbing another's action target? If the latter seems to be out of the agent's reach, will this impact on people's gaze behaviour? We recorded proactive eye movements while participants witnessed someone else trying to reach for and grasp objects located either within or outside his reach. Proactivity of gaze was impaired when the targets were just out of the agent's reach. This effect is likely to be due to an interpersonal bodily space representation that allows one to map another's reaching space, thus prompting proactive eye movements towards the target just in case the agent is in the position to act upon it. PMID:22524520

Costantini, Marcello; Ambrosini, Ettore; Sinigaglia, Corrado

2012-01-01

60

Reaching ignition in the tokamak  

SciTech Connect

This review covers the following areas: (1) the physics of burning plasmas, (2) plasma physics requirements for reaching ignition, (3) design studies for ignition devices, and (4) prospects for an ignition project. (MOW)

Furth, H.P.

1985-06-01

61

An Assessment of EU 2020 Strategy: Too Far to Reach?  

ERIC Educational Resources Information Center

In 2010, EU adopted a new growth strategy which includes three growth priorities and five headline targets to be reached by 2020. The aim of this paper is to investigate the current performance of the EU member and candidate states in achieving these growth priorities and the overall strategy target by allocating the headline targets into the…

Colak, Mehmet Selman; Ege, Aylin

2013-01-01

62

[The establishment of the maximum permissible concentration of the new plant growth stimulant T-86 in the air of a work area].  

PubMed

LD50 of plant growth stimulator T-86 was determined at the levels: 7500 mg/kg for rats, 1475 mg/kg for white mice, and 5000 mg/kg for rabbits. Moderate skin resorptive effect of the agent was revealed. Limac of T-86 is 290 mg/m3, Limch 12 mg/m3, threshold embryotoxic effect 5.2 mg/m3, and MAC for work zone air 0.5 mg/m3. PMID:10560187

Abdrashitova, E V

1999-01-01

63

Growth condition and bacterial community for maximum hydrolysis of suspended organic materials in anaerobic digestion of food waste-recycling wastewater.  

PubMed

This paper reports the effects of changing pH (5-7) and temperature (T, 40-60 degrees C) on the efficiencies of bacterial hydrolysis of suspended organic matter (SOM) in wastewater from food waste recycling (FWR) and the changes in the bacterial community responsible for this hydrolysis. Maximum hydrolysis efficiency (i.e., 50.5% reduction of volatile suspended solids) was predicted to occur at pH 5.7 and T = 44.5 degrees C. Changes in short-chain volatile organic acid profiles and in acidogenic bacterial communities were investigated under these conditions. Propionic and butyric acids concentrations increased rapidly during the first 2 days of incubation. Several band sequences consistent with Clostridium spp. were detected using denaturing gel gradient electrophoresis. Clostridium thermopalmarium and Clostridium novyi seemed to contribute to butyric acid production during the first 1.5 days of acidification of FWR wastewater, and C. thermopalmarium was a major butyric acid producer afterward. C. novyi was an important propionic acid producer. These two species appear to be important contributors to hydrolysis of SOM in the wastewater. Other acidogenic anaerobes, Aeromonas sharmana, Bacillus coagulans, and Pseudomonas plecoglossicida, were also indentified. PMID:19894044

Kim, Man Deok; Song, Minkyung; Jo, Minho; Shin, Seung Gu; Khim, Jee Hyeong; Hwang, Seokhwan

2010-02-01

64

REACH. Residential Electrical Wiring Units.  

ERIC Educational Resources Information Center

As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of residential electrical wiring. The instructional units focus on grounded outlets, service entrance, and blueprint reading. Each unit follows a typical format…

Ansley, Jimmy; Ennis, Mike

65

Reaching All Students with Mathematics.  

ERIC Educational Resources Information Center

The National Council of Teachers of Mathematics'"Curriculum and Evaluation Standards for School Mathematics" and "Professional Standards for Teaching Mathematics" reflect the belief that all students can learn a significant core of high-quality mathematics. Recognizing the magnitude of the task of reaching all students, this book was put together…

Cuevas, Gilbert, Ed.; Driscoll, Mark, Ed.

66

Records Reaching Recording Data Technologies  

NASA Astrophysics Data System (ADS)

The goal of RECORDS (Reaching Recording Data Technologies) is the digital capturing of buildings and cultural heritage objects in hard-to-reach areas and the combination of data. It is achieved by using a modified crane from film industry, which is able to carry different measuring systems. The low-vibration measurement should be guaranteed by a gyroscopic controlled advice that has been , developed for the project. The data were achieved by using digital photography, UV-fluorescence photography, infrared reflectography, infrared thermography and shearography. Also a terrestrial 3D laser scanner and a light stripe topography scanner have been used The combination of the recorded data should ensure a complementary analysis of monuments and buildings.

Gresik, G. W. L.; Siebe, S.; Drewello, R.

2013-07-01

67

Estimation of alga growth stage and lipid content growth rate  

NASA Technical Reports Server (NTRS)

Method and system for estimating a growth stage of an alga in an ambient fluid. Measured light beam absorption or reflection values through or from the alga and through an ambient fluid, in each of two or more wavelength sub-ranges, are compared with reference light beam absorption values for corresponding wavelength sub-ranges for in each alga growth stage to determine (1) which alga growth stage, if any, is more likely and (2) whether estimated lipid content of the alga is increasing or has peaked. Alga growth is preferably terminated when lipid content has approximately reached a maximum value.

Embaye, Tsegereda N. (Inventor); Trent, Jonathan D. (Inventor)

2012-01-01

68

Changes in biologically active ultraviolet radiation reaching the Earth's surface  

Microsoft Academic Search

Stratospheric ozone levels are near their lowest point since measurements began, so current ultraviolet-B (UV-B ) radiation levels are thought to be close to their maximum. Total stratospheric content of ozone-depleting substances is expected to reach a maximum before the year 2000. All other things eing equal, the current ozone losses and related UV-B increases should be close to their

S. Madronich; R. L. McKenzie; L. O. Björn; M. M. Caldwell; M. Ilyas

1998-01-01

69

RV strings of maximum curvature  

SciTech Connect

To design an effective interceptor for a string of reentry vehicles (RV's) released by a post-boost vehicle (PBV), it is necessary to have information about possible geometries of the string when it reaches a given altitude above the target. The geometry of the string, assumed for simplicity to contain three RV's, is determined by the motion of the PBV which is controlled by varying its thrust direction. Of interest in this study is maximizing the curvature of the string, which is represented by the distance of RV{sub 2} from the line joining RV{sub 1} and RV{sub 3} when RV{sub 1} reaches the intercept attitude, subject to the constraints that all three RV's must land within 3000 ft distance of the target. The maximum curvature problem is formulated as a parameter optimization problem and solved by a nonlinear programming code known as GRG2. The thrust angles are assumed to be piecewise linear, and a total of 21 parameters is used. The maximum curvature is shown to be approximately 2900 ft. 4 refs., 8 figs.

Hull, D.G. (Texas Univ., Austin, TX (United States)); Zazworsky, R.M. (Sandia National Labs., Albuquerque, NM (United States))

1991-01-01

70

[When the throug is reached].  

PubMed

The only option for a patient suffering from severe chronic obstructive pulmonary disease (COPD) despite fully developed medical therapy inclusive eventually supplemental oxygen is either lung transplantation or lung-volume-reduction surgery (LVRS). Indication for LVRS is based on the results of a large prostective controlled clinical trial and patients are selected for this intervention based on particular functional and radiomorphologic criteria. We report a patient with far advanced COPD, no longer able to walk to the toilette without support. Based on clinical reasoning and our experience with other unique cases the patient underwent unilateral LVRS despite a lack of scientific evidence that she might profit from this intervention. Luckily, the perioperative course was uneventful and she experienced an impressive subjective and objective improvement. This case illustrates, that in desperate situations it may be necessary to reach a therapeutic decision outside scientifically based evidence. PMID:19048527

Turk, Alexander J; Russi, Erich W

2008-12-01

71

Maximum Score Type Estimators  

Microsoft Academic Search

This paper presents maximum score type estimators for linear, binomial, tobit and truncated regression models. These estimators estimate the normalized vector of slopes and do not provide the estimator of intercept, although it may appear in the model. Strong consistency is proved. In addition, in the case of truncated and tobit regression models, maximum score estimators allow restriction of the

Marcin Owczarczuk

2009-01-01

72

Infrastructure for Reaching Disadvantaged Consumers  

PubMed Central

Both consumers and health service providers need access to up-to-date information, including patient and practice guidelines, that allows them to make decisions in partnership about individual and public health in line with the primary health care model of health service delivery. Only then is it possible for patient preferences to be considered while the health of the general population is improved. The Commonwealth Government of Australia has allocated $250 million over five years, starting July 1, 1997, to support activities and projects designed to meet a range of telecommunication needs in regional, rural, and remote Australia. This paper defines rural and remote communities, then reviews rural and remote health services, information, and telecommunication technology infrastructures and their use in Australia to establish the current state of access to information tools by rural and remote communities and rural health workers in Australia today. It is argued that a suitable telecommunication infrastructure is needed to reach disadvantaged persons in extremely remote areas and that intersectoral support is essential to build this infrastructure. In addition, education will make its utilization possible.

Hovenga, Evelyn J. S.; Hovel, Joe; Klotz, Jeanette; Robins, Patricia

1998-01-01

73

Agreement Reached on Fiji Hostages  

NSDL National Science Digital Library

Fiji's military rulers and the group of gunmen holding 31 members of the former government hostage have apparently reached a deal that will end the five-week political crisis and free the hostages "within days." The crisis began when a group led by George Speight raided the parliament building on May 19, demanding more power for indigenous Fijians. Most of the demands made by Speight -- that the 1997 multiracial constitution be thrown out and that Prime Minister Mahendra Chaudhry, Fiji's first prime minister of Indian descent, be fired -- have already been met. In the 36 days since the storming of parliament, Fiji's economy has entered a steep downward spiral. On May 29, the military declared martial law and assumed control of the government. On June 6, Fiji was suspended from the Commonwealth, and Australia, New Zealand, and the United States have threatened economic sanctions if Fiji is not restored to democracy. Meanwhile, Australian trade unions have refused to handle cargo to and from Fiji, freezing much of the country's exports. The garment, sugar, and tourism industries have all reported large losses and layoffs. The military regime has announced that the details of the deal will be made known tomorrow, and the hostages will then be released. Previous announcements regarding their release, however, have come to nothing. Once the immediate crisis is solved, the military has said they will continue to run the country for another three months and would then create an interim government to make preparations for new elections within two years.

De Nie, Michael W.

74

Maximum thrust mode evaluation  

NASA Technical Reports Server (NTRS)

Measured reductions in acceleration times which resulted from the application of the F-15 performance seeking control (PSC) maximum thrust mode during the dual-engine test phase is presented as a function of power setting and flight condition. Data were collected at altitudes of 30,000 and 45,000 feet at military and maximum afterburning power settings. The time savings for the supersonic acceleration is less than at subsonic Mach numbers because of the increased modeling and control complexity. In addition, the propulsion system was designed to be optimized at the mid supersonic Mach number range. Recall that even though the engine is at maximum afterburner, PSC does not trim the afterburner for the maximum thrust mode. Subsonically at military power, time to accelerate from Mach 0.6 to 0.95 was cut by between 6 and 8 percent with a single engine application of PSC, and over 14 percent when both engines were optimized. At maximum afterburner, the level of thrust increases were similar in magnitude to the military power results, but because of higher thrust levels at maximum afterburner and higher aircraft drag at supersonic Mach numbers the percentage thrust increase and time to accelerate was less than for the supersonic accelerations. Savings in time to accelerate supersonically at maximum afterburner ranged from 4 to 7 percent. In general, the maximum thrust mode has performed well, demonstrating significant thrust increases at military and maximum afterburner power. Increases of up to 15 percent at typical combat-type flight conditions were identified. Thrust increases of this magnitude could be useful in a combat situation.

Orme, John S.; Nobbs, Steven G.

1995-01-01

75

The Maximum Sinkage of a Ship  

Microsoft Academic Search

A ship moving steadily forward in shallow water of constant depth h is usually subject to downward forces and hence squat, which is a potentially dangerous sinkage or increase in draft. Sinkage increases with ship speed, until it reaches a maximum at just below the critical speed p gh. Here we use both a linear transcritical shallow-water equation and a

T. P. Gourlay; E. O. Tuck

76

Croatia has reached iodine sufficiency.  

PubMed

This study was performed in 2002, 6 yr after the introduction of a new regulation on salt iodination with 25 mg KI/kg of salt. The aim of the study was to evaluate whether further significant positive results of improved iodine intake could be observed among schoolchildren in Croatia. A total of 927 schoolchildren of both sexes, aged 6-12 yr, were included in the study. In Croatia, with a population of 4,437,460 the research was implemented in four major geographical regions: the Northwestern, Slavonia, Northern Adriatic and Dalmatian regions. Investigations included randomly selected pupils from regional centers and neighboring smaller towns or villages. The results have revealed that thyroid volumes were within the normal range according to the provisional WHO/ICCIDD reference values for sonographic thyroid volume in iodine-replete school-age children, updated in 2001. A significant improvement in medians of urinary iodine excretion was detected in 2002: from 9 microg/dl in 1991 to 14.6 microg/dl in Zagreb, from 4.3 microg/dl in 1995 to 13.1 microg/dl in Split, from 9.4 microg/dl in 1997 to 14.2 microg/dl in Rijeka and from 13.4 microg/dl in 1997 to 14.7 microg/dl in Osijek. An overall median of 14.0 microg/dl of urinary iodine excretion was detected in Croatian schoolchildren. The control of salt at different levels, from production to consumption, including salt produced in all three Croatian salt plants and imported salt, revealed that Croatian salt is adequately iodized. From severe iodine deficiency before the 1950s, through mild-to-moderate iodine deficiency in the 1990s, Croatia has now reached iodine sufficiency. PMID:14669828

Kusi?, Z; Novosel, S A; Dabeli?, N; Punda, M; Roncevi?, S; Labar, Z; Lukinac, Lj; Nöthig-Hus, D; Stanici?, A; Kai?-Rak, A; Mesaros-Kanjski, E; Karner, I; Smoje, J; Milanovi?, N; Kataleni?, M; Juresa, V; Sarnavka, V

2003-08-01

77

The maximum likelihood degree  

Microsoft Academic Search

Maximum likelihood estimation in statistics leads to the problem of\\u000amaximizing a product of powers of polynomials. We study the algebraic degree of\\u000athe critical equations of this optimization problem. This degree is related to\\u000athe number of bounded regions in the corresponding arrangement of\\u000ahypersurfaces, and to the Euler characteristic of the complexified complement.\\u000aUnder suitable hypotheses, the maximum

Serkan Hosten; Amit Khetan; Bernd Sturmfels

2006-01-01

78

Maximum ratio transmission  

Microsoft Academic Search

This paper presents the concept, principles, and analysis of maximum ratio transmission for wireless communications, where multiple antennas are used for both transmission and reception. The principles and analysis are applicable to general cases, including maximum-ratio combining. Simulation results agree with the analysis. The analysis shows that the average overall signal-to-mise ratio (SNR) is proportional to the cross correlation between

Titus K. Y. Lo

1999-01-01

79

Tuning in to Another Person's Action Capabilities: Perceiving Maximal Jumping-Reach Height from Walking Kinematics  

ERIC Educational Resources Information Center

Three experiments investigated the ability to perceive the maximum height to which another actor could jump to reach an object. Experiment 1 determined the accuracy of estimates for another actor's maximal reach-with-jump height and compared these estimates to estimates of the actor's standing maximal reaching height and to estimates of the…

Ramenzoni, Veronica; Riley, Michael A.; Davis, Tehran; Shockley, Kevin; Armstrong, Rachel

2008-01-01

80

Colony growth and the ontogeny of worker polymorphism in the fire ant, Solenopsis invicta  

Microsoft Academic Search

Colony size and worker polymorphism (headwidth) were determined for fire ant colonies ranging from incipient to 12 years of age. Colonies grew approximately logistically, reaching half size between 21\\/2 and 31\\/2 yr and reaching their maximum size of about 220000 workers after 4 to 6 yr. Colony size showed strong seasonal variation. There was some evidence that growth rate may

Walter R. Tschinkel

1988-01-01

81

ALMA telescope reaches new heights  

NASA Astrophysics Data System (ADS)

The ALMA (Atacama Large Millimeter/submillimeter Array) astronomical observatory has taken another step forward - and upwards. One of its state-of-the-art antennas was carried for the first time to the 5000m plateau of Chajnantor, in the Chilean Andes, on the back of a custom-built giant transporter. The antenna, which weighs about 100 tons and has a diameter of 12 metres, was transported up to the high-altitude Array Operations Site, where the extremely dry and rarefied air is ideal for ALMA's observations of the Universe. The conditions at the Array Operations Site on Chajnantor, while excellent for astronomy, are also very harsh. Only half as much oxygen is available as at sea level, making it very difficult to work there. This is why ALMA's antennas are assembled and tested at the lower 2900 m altitude of the ALMA Operations Support Facility. It was from this relatively hospitable base camp that the ALMA antenna began its journey to the high Chajnantor site. "This is an important moment for ALMA. We are very happy that the first transport of an antenna to the high site went flawlessly. This achievement was only possible through contributions from all international ALMA partners: this particular antenna is provided by Japan, the heavy-lift transporter by Europe, and the receiving electronics inside the antenna by North America, Europe, and Asia", said Wolfgang Wild, European ALMA Project Manager. The trip began when one of the two ALMA transporters, named Otto, lifted the antenna onto its back. It then carried its heavy load along the 28 km road from the Operations Support Facility up to the Array Operations Site. While the transporter is capable of speeds of up to 12 km/hour when carrying an antenna, this first journey was made more slowly to ensure that everything worked as expected, taking about seven hours. The ALMA antennas are the most advanced submillimetre-wavelength antennas ever made. They are designed to operate fully exposed in the harsh conditions of the Array Operations Site. This means surviving strong winds and temperatures between +20 and -20 Celsius whilst being able to point precisely enough that they could pick out a golf ball at a distance of 15 km, and to keep their smooth reflecting surfaces accurate to better than 25 micrometres (less than the typical thickness of a human hair). Once the transporter reached the high plateau it carried the antenna to a concrete pad - a docking station with connections for power and fibre optics - and positioned it with an accuracy of a few millimetres. The transporter is guided by a laser steering system and, just like some cars today, also has ultrasonic collision detectors. These sensors ensure the safety of the state-of-the-art antennas as the transporter drives them across what will soon be a rather crowded plateau. Ultimately, ALMA will have at least 66 antennas distributed over about 200 pads, spread over distances of up to 18.5 km and operating as a single, giant telescope. Even when ALMA is fully operational, the transporters will be used to move the antennas between pads to reconfigure the telescope for different kinds of observations. "Transporting our first antenna to the Chajnantor plateau is a epic feat which exemplifies the exciting times in which ALMA is living. Day after day, our global collaboration brings us closer to the birth of the most ambitious ground-based astronomical observatory in the world", said Thijs de Graauw, ALMA Director. This first ALMA antenna at the high site will soon be joined by others and the ALMA team looks forward to making their first observations from the Chajnantor plateau. They plan to link three antennas by early 2010, and to make the first scientific observations with ALMA in the second half of 2011. ALMA will help astronomers answer important questions about our cosmic origins. The telescope will observe the Universe using light with millimetre and submillimetre wavelengths, between infrared light and radio waves in the electromagnetic spectrum. Light at these wavelengths comes from some of th

2009-09-01

82

What causes cooling water temperature gradients in forested stream reaches?  

NASA Astrophysics Data System (ADS)

Previous studies have suggested that shading by riparian vegetation may reduce maximum water temperature and provide refugia for temperature sensitive aquatic organisms. Longitudinal cooling gradients have been observed during the daytime for stream reaches shaded by coniferous trees downstream of clear cuts, or deciduous woodland downstream of open moorland. However, little is known about the energy exchange processes that drive such gradients, especially in semi-natural woodland contexts, and in the absence of potentially confounding cool groundwater inflows. To address this gap, this study quantified and modelled variability in stream temperature and heat fluxes along an upland reach of the Girnock Burn (a tributary of the Aberdeenshire Dee, Scotland) where riparian landuse transitions from open moorland to semi-natural forest. Observations were made along a 1050 m reach using a spatially-distributed network of ten water temperature micro-loggers, three automatic weather stations and >200 hemispherical photographs, which were used to estimate incoming solar radiation. These data parameterised a high-resolution energy flux model, incorporating flow-routing, which predicted spatio-temporal variability in stream temperature. Variability in stream temperature was controlled largely by energy fluxes at the water column-atmosphere interface. Predominantly net energy gains occurred along the reach during daylight hours, and heat exchange across the bed-water column interface accounted for <1% of the net energy budget. For periods when daytime net radiation gains were high (under clear skies), differences between water temperature observations decreased in the streamwise direction; a maximum difference of 2.5 °C was observed between the upstream reach boundary and 1050 m downstream. Furthermore, daily maximum water temperature at 1050 m downstream was ?1°C cooler than at the upstream reach boundary and lagged the occurrence of daily maximum water temperature upstream by >1h. Temperature gradients were not generated by cooling of stream water, but rather by a combination of reduced rates of heating in the woodland reach and advection of cooler (overnight and early morning) water from the upstream moorland catchment. Longitudinal thermal gradients were indistinct at night and on days when net radiation gains were low (under over-cast skies), thus when changes in net energy gains or losses did not vary significantly in space and time, and heat advected into the reach was reasonably consistent. The findings of the study and the modelling approach employed are useful tools for assessing optimal planting strategies for mitigating against ecologically damaging stream temperature maxima.

Garner, G.; Malcolm, I. A.; Sadler, J. P.; Hannah, D. M.

2014-06-01

83

The Maximum Principle.  

National Technical Information Service (NTIS)

A relatively simple proof of the maximum principle is presented. The main objective was to obtain a proof, similar to that due to Halkin, but replacing the use of Brouwer's fixed point theorem by an easily proven contraction mapping theorem. The first use...

G. F. Bryant D. Q. Mayne

1973-01-01

84

Human Factors Requirements for Fingertip Reach Controls.  

National Technical Information Service (NTIS)

This project was instituted to develop human factors recommendations for fingertip reach controls. Interviews were conducted with 405 drivers of cars equipped with fingertip reach controls. A high percentage of finding problems was reported when the horn ...

R. R. Mourant E. Moussa-Hamouda J. M. Howard

1977-01-01

85

New symmetry of intended curved reaches  

PubMed Central

Background Movement regularities are inherently present in automated goal-directed motions of the primate's arm system. They can provide important signatures of intentional behaviours driven by sensory-motor strategies, but it remains unknown if during motor learning new regularities can be uncovered despite high variability in the temporal dynamics of the hand motions. Methods We investigated the conservation and violation of new movement regularity obtained from the hand motions traced by two untrained monkeys as they learned to reach outwardly towards spatial targets while avoiding obstacles in the dark. The regularity pertains to the transformation from postural to hand paths that aim at visual goals. Results In length-minimizing curves the area enclosed between the Euclidean straight line and the curve up to its point of maximum curvature is 1/2 of the total area. Similar trend is found if one examines the perimeter. This new movement regularity remained robust to striking changes in arm dynamics that gave rise to changes in the speed of the reach, to changes in the hand path curvature, and to changes in the arm's postural paths. The area and perimeter ratios characterizing the regularity co-varied across repeats of randomly presented targets whenever the transformation from posture to hand paths was compliant with the intended goals. To interpret this conservation and the cases in which the regularity was violated and recovered, we provide a geometric model that characterizes arm-to-hand and hand-to-arm motion paths as length minimizing curves (geodesics) in a non-Euclidean space. Whenever the transformation from one space to the other is distance-metric preserving (isometric) the two symmetric ratios co-vary. Otherwise, the symmetric ratios and their co-variation are violated. As predicted by the model we found empirical evidence for the violation of this movement regularity whenever the intended goals mismatched the actions. This was manifested in unintended curved "after-effect" trajectories executed in the absence of obstacles. In this case, the system was "perturbed" away from the symmetry but after several repeats it recovered its default state. Conclusions We propose this movement regularity as a sensory-motor transformation invariant of intentional acts.

2010-01-01

86

REACH: impact on the US cosmetics industry?  

PubMed

The Registration, Evaluation, Authorization and restriction of Chemicals (REACH) is a recent European regulation on chemical substances meant to protect human health and the environment. REACH imposes the "precautionary principle" where additional data and definitive action are required when uncertainty is identified. The cosmetics industry is only partially concerned by REACH: while the stages of registration and evaluation apply to cosmetics, those of authorization and restriction most likely will not, as cosmetic ingredients are already subject to regulation by various agencies and directives. REACH has potential benefits to the industry including the possibility of reassuring consumers and improving their image of chemicals and cosmetics. However, REACH also has potential disadvantages, mainly with regard to impeding innovation. The American cosmetics industry will be affected by REACH, because all US manufacturers who export substances to Europe will have to fully comply with REACH. PMID:19250158

Pouillot, Anne; Polla, Barbara; Polla, Ada

2009-03-01

87

Efficiency of Isothermal Molecular Machines at Maximum Power  

NASA Astrophysics Data System (ADS)

We derive upper and lower bounds for the efficiency of an isothermal molecular machine operating at maximum power. The upper bound is reached when the activated state is close to the fueling or reactant state (Eyring-like), while the lower bound is reached when the activated state is close to the product state (Kramers-like).

Van den Broeck, Christian; Kumar, Niraj; Lindenberg, Katja

2012-05-01

88

Efficiency of isothermal molecular machines at maximum power.  

PubMed

We derive upper and lower bounds for the efficiency of an isothermal molecular machine operating at maximum power. The upper bound is reached when the activated state is close to the fueling or reactant state (Eyring-like), while the lower bound is reached when the activated state is close to the product state (Kramers-like). PMID:23003230

Van den Broeck, Christian; Kumar, Niraj; Lindenberg, Katja

2012-05-25

89

EXECUTIVE SUMMARY: REACH OUT AND READ ASSESSMENT  

Microsoft Academic Search

The Reach Out and Read Assessment (RORA) project was a quasi-experimental study designed to evaluate the effectiveness of a Reach Out and Read program. Reach Out and Read (ROR) is a non-profit, national organization that features giving parenting and literacy information to families. Books are given to their children at well-child visits between the ages of six months and five

Jacqueline Gramann

90

Seasonal variations of growth and agar composition of Gracilaria multipartita harvested along the Atlantic coast of Morocco  

Microsoft Academic Search

The biology and agar composition and properties of Gracilaria multipartita, a common species along the coasts of Morocco, have been studied on samples collected monthly for one year. Growth of the alga was maximum in spring and autumn, and the seaweed partially decayed after its maximum fertility was reached in June and October. The agar content and composition showed seasonal

Thierry Givernaud; Abderrazak El Gourji; Aziza Mouradi-Givernaud; Yves Lemoine; Nadia Chiadmi

1999-01-01

91

Introduction to maximum entropy  

SciTech Connect

The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. We review the need for such methods in data analysis and show, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. We conclude with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab.

Sivia, D.S.

1988-01-01

92

Calibrating Reach Distance to Visual Targets  

ERIC Educational Resources Information Center

The authors investigated the calibration of reach distance by gradually distorting the haptic feedback obtained when participants grasped visible target objects. The authors found that the modified relationship between visually specified distance and reach distance could be captured by a straight-line mapping function. Thus, the relation could be…

Mon-Williams, Mark; Bingham, Geoffrey P.

2007-01-01

93

School Furniture Dimensions: Standing and Reaching.  

ERIC Educational Resources Information Center

Performance of school children in regard to their standing and reach postures are described with dimensions given on the limits of their performance only. The facts of task performances are presented for the following tasks--(1) seeing into a shelf, (2) reaching into a shelf, (3) drawing on a vertical surface, (4) sitting or standing while…

Department of Education and Science, London (England).

94

Always Connected, but Hard to Reach  

ERIC Educational Resources Information Center

Students seem to be always connected through their computers, personal digital assistants (PDAs), or mobile phones, making it easy to reach them--if you are a peer. For colleges and universities, reaching students with timely and relevant information often proves a challenge. With rapid changes in both technology and social practices, what should…

Rishi, Raju

2007-01-01

95

The Database for Reaching Experiments and Models  

PubMed Central

Reaching is one of the central experimental paradigms in the field of motor control, and many computational models of reaching have been published. While most of these models try to explain subject data (such as movement kinematics, reaching performance, forces, etc.) from only a single experiment, distinct experiments often share experimental conditions and record similar kinematics. This suggests that reaching models could be applied to (and falsified by) multiple experiments. However, using multiple datasets is difficult because experimental data formats vary widely. Standardizing data formats promises to enable scientists to test model predictions against many experiments and to compare experimental results across labs. Here we report on the development of a new resource available to scientists: a database of reaching called the Database for Reaching Experiments And Models (DREAM). DREAM collects both experimental datasets and models and facilitates their comparison by standardizing formats. The DREAM project promises to be useful for experimentalists who want to understand how their data relates to models, for modelers who want to test their theories, and for educators who want to help students better understand reaching experiments, models, and data analysis.

Walker, Ben; Kording, Konrad

2013-01-01

96

Interference of Different Types of Seats on Postural Control System during a Forward-Reaching Task in Individuals with Paraplegia  

ERIC Educational Resources Information Center

We aimed to evaluate the influence of different types of wheelchair seats on paraplegic individuals' postural control using a maximum anterior reaching test. Balance evaluations during 50, 75, and 90% of each individual's maximum reach in the forward direction using two different cushions on seat (one foam and one gel) and a no-cushion condition…

de Abreu, Daniela Cristina Carvalho; Takara, Kelly; Metring, Nathalia Lopes; Reis, Julia Guimaraes; Cliquet, Alberto, Jr.

2012-01-01

97

Growth  

NASA Astrophysics Data System (ADS)

This chapter is devoted to the growth of ZnO. It starts with various techniques to grow bulk samples and presents in some detail the growth of epitaxial layers by metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and pulsed laser deposition (PLD). The last section is devoted to the growth of nanorods. Some properties of the resulting samples are also presented. If a comparison between GaN and ZnO is made, very often the huge variety of different growth techniques available to fabricate ZnO is said to be an advantage of this material system. Indeed, growth techniques range from low cost wet chemical growth at almost room temperature to high quality MOCVD growth at temperatures above 1, 000?C. In most cases, there is a very strong tendency of c-axis oriented growth, with a much higher growth rate in c-direction as compared to other crystal directions. This often leads to columnar structures, even at relatively low temperatures. However, it is, in general, not straight forward to fabricate smooth ZnO thin films with flat surfaces. Another advantage of a potential ZnO technology is said to be the possibility to grow thin films homoepitaxially on ZnO substrates. ZnO substrates are mostly fabricated by vapor phase transport (VPT) or hydrothermal growth. These techniques are enabling high volume manufacturing at reasonable cost, at least in principle. The availability of homoepitaxial substrates should be beneficial to the development of ZnO technology and devices and is in contrast to the situation of GaN. However, even though a number of companies are developing ZnO substrates, only recently good quality substrates have been demonstrated. However, these substrates are not yet widely available. Still, the situation concerning ZnO substrates seems to be far from low-cost, high-volume production. The fabrication of dense, single crystal thin films is, in general, surprisingly difficult, even when ZnO is grown on a ZnO substrate. However, molecular beam epitaxy (MBE) delivers high quality ZnMgO-ZnO quantum well structures. Other thin film techniques such as PLD or MOCVD are also widely used. The main problem at present is to consistently achieve reliable p-type doping. For this topic, see also Chap. 5. In the past years, there have been numerous publications on p-type doping of ZnO, as well as ZnO p-n junctions and light emitting diodes (LEDs). However, a lot of these reports are in one way or the other inconsistent or at least incomplete. It is quite clear from optical data that once a reliable hole injection can be achieved, high brightness ZnO LEDs should be possible. In contrast to that expectation, none of the LEDs reported so far shows efficient light emission, as would be expected from a reasonable quality ZnO-based LED. See also Chap. 13. As a matter of fact, there seems to be no generally accepted and reliable technique for p-type doping available at present. The reason for this is the unfavorable position of the band structure of ZnO relative to the vacuum level, with a very low lying valence band. See also Fig. 5.1. This makes the incorporation of electrically active acceptors difficult. Another difficulty is the huge defect density in ZnO. There are many indications that defects play a major role in transport and doping. In order to solve the doping problem, it is generally accepted that the quality of the ZnO material grown by the various techniques needs to be improved. Therefore, the optimization of ZnO epitaxy is thought to play a key role in the further development of this material system. Besides being used as an active material in optoelectronic devices, ZnO plays a major role as transparent contact material in thin film solar cells. Polycrystalline, heavily n-type doped ZnO is used for this, combining a high electrical conductivity with a good optical transparency. In this case, ZnO thin films are fabricated by large area growth techniques such as sputtering. For this and other applications, see also Chap. 13.

Waag, Andreas

98

Growth characteristics of aquatic macrophytes cultured in nutrient-enriched water: I. Water hyacinth, water lettuce, and pennywort  

Microsoft Academic Search

Seasonal growth characteristics and biomass yield potential of 3 floating aquatic macrophytes cultured in nutrient nonlimiting\\u000a conditions were evaluated in central Florida’s climatic conditions. Growth cycle (growth curve) of the plants was found to\\u000a be complete when maximum plant density was reached and no additional increase in growth was recorded. Biomass yield per unit\\u000a area and time was found to

K. R. Reddy; W. F. Debusk

1984-01-01

99

Patterns of individual growth of gray garden slug Deroceras reticulatum  

Microsoft Academic Search

Individual growth of gray garden slug Deroceras reticulatum was studied under laboratory conditions in the period from collection to death. The studied population demonstrated different\\u000a patterns of growth. Three groups of slugs were recognized: (1) slugs that reached the maximum weight after 4 months of raring,\\u000a after which their weight rapidly decreased (the life span in culture was 6–7 months);

A. A. Zotin

2007-01-01

100

Faster Edge-Define Silicon-Ribbon Growth  

NASA Technical Reports Server (NTRS)

End-cooling allows faster growth and yields single-crystal ribbons. Improvement in edge-defined film-fed process for growing silicon ribbons increases speed of growth and improves quality of silicon product. Also produces silicon sheets, webs, or boules. Cold shoes cool melt at ends of emerging sheet. Since solidification at ends now occurs before end menisci reach maximum height, ribbon drawn substantially faster.

Richter, R.

1986-01-01

101

Extended reach eyed for Wytch Farm  

SciTech Connect

This paper reports that major advances in extended reach drilling into shallow pays during the past year have enabled BP Exploration to revamp is plans to develop the offshore portion of Wytch Farm oil field on the south coast of England. Instead of building an artifical island, BP will drill about 14 wells with a reach of as much as 5 km (3.105 miles) from existing and new well sites on the coast. The wells will recover about 80% of reserves that would have been reached from an artificial island. The key element in BP's change of plans was completion of an extended reach well in a shallow reservoir by Forest Oil Corp. in the Gulf of Mexico and Unocal Corp.'s extended reach well drilled last October from Platform Irene off California in Point Pedernales field. Forest drilled its OCS-G-5518A6 from a surface location in Block 325 to a bottomhole location in Block 326, both in the Eugene Island area off Louisiana.

Not Available

1992-01-06

102

The sun and heliosphere at solar maximum  

NASA Technical Reports Server (NTRS)

Recent Ulysses observations from the Sun's equator to the poles reveal fundamental properties of the three-dimensional heliosphere at the maximum in solar activity. The heliospheric magnetic field originates from a magnetic dipole oriented nearly perpendicular to, instead of nearly parallel to, the Sun'rotation axis. Magnetic fields, solar wind, and energetic charged particles from low-latitude sources reach all latitudes, including the polar caps. The very fast high-latitude wind and polar coronal holes disappear and reappear together. Solar wind speed continues to be inversely correlated with coronal temperature. The cosmic ray flux is reduced symmetrically at all latitudes.

Smith, E. J.; Marsden, R. G.; Balogh, A.; Gloeckler, G.; Geiss, J.; McComas, D. J.; McKibben, R. B.; MacDowall, R. J.; Lanzerotti, L. J.; Krupp, N.; Krueger, H.; Landgraf, M.

2003-01-01

103

Inactivation of the Parietal Reach Region Causes Optic Ataxia, Impairing Reaches but Not Saccades  

PubMed Central

SUMMARY Lesions in human posterior parietal cortex can cause optic ataxia (OA), in which reaches but not saccades to visual objects are impaired, suggesting separate visuomotor pathways for the two effectors. In monkeys, one potentially crucial area for reach control is the parietal reach region (PRR), in which neurons respond preferentially during reach planning as compared to saccade planning. However, direct causal evidence linking the monkey PRR to the deficits observed in OA is missing. We thus inactivated part of the macaque PRR, in the medial wall of the intraparietal sulcus, and produced the hallmarks of OA, misreaching for peripheral targets but unimpaired saccades. Furthermore, reach errors were larger for the targets preferred by the neural population local to the injection site. These results demonstrate that PRR is causally involved in reach-specific visuomotor pathways, and reach goal disruption in PRR can be a neural basis of OA.

Hwang, Eun Jung; Hauschild, Markus; Wilke, Melanie; Andersen, Richard A.

2013-01-01

104

Reaching African American men: a qualitative analysis.  

PubMed

African American men are disproportionately affected by most illnesses and associated complications. These men are also less likely to participate in primary and secondary prevention interventions. Little is known about reaching them. The purpose of this study(1) was to explore factors associated with effectively reaching African American men. Ethnographic methods were used. Key and general informants from an urban Northeastern community were recruited for this study. The data revealed 3 major themes as essential to reaching African American men: a trusted and respected community member providing the outreach, a perceived safe and caring environment during outreach, and a perceived benefit from participating in the outreach. The findings from this study provided a foundation for designing community interventions that will increase participation among African American men. Future research efforts should focus on operationalizing these findings in the community. PMID:16863400

Plowden, Keith O; John, Wendell; Vasquez, Elias; Kimani, James

2006-01-01

105

Unconstrained reaching modulates eye-hand coupling.  

PubMed

Eye–hand coordination is a crucial element of goal-directed movements. However, few studies have looked at the extent to which unconstrained movements of the eyes and hand made to targets influence each other. We studied human participants who moved either their eyes or both their eyes and hand to one of three static or flashed targets presented in 3D space. The eyes were directed, and hand was located at a common start position on either the right or left side of the body. We found that the velocity and scatter of memory-guided saccades (flashed targets) differed significantly when produced in combination with a reaching movement than when produced alone. Specifically, when accompanied by a reach, peak saccadic velocities were lower than when the eye moved alone. Peak saccade velocities, as well as latencies, were also highly correlated with those for reaching movements, especially for the briefly flashed targets compared to the continuous visible target. The scatter of saccade endpoints was greater when the saccades were produced with the reaching movement than when produced without, and the size of the scatter for both saccades and reaches was weakly correlated. These findings suggest that the saccades and reaches made to 3D targets are weakly to moderately coupled both temporally and spatially and that this is partly the result of the arm movement influencing the eye movement. Taken together, this study provides further evidence that the oculomotor and arm motor systems interact above and beyond any common target representations shared by the two motor systems. PMID:24121521

Lee, Dongpyo; Poizner, Howard; Corcos, Daniel M; Henriques, Denise Y

2014-01-01

106

BSP\\/CGM Algorithms for Maximum Subsequence and Maximum Subarray  

Microsoft Academic Search

\\u000a The maximum subsequence problem finds the contiguous subsequence of n real numbers with the highest sum. This problem appears in the analysis of DNA or protein sequences. It can be solved sequentially\\u000a in O(n) time. In the 2-D version, given an n × n array A, the maximum subarray of A is the contiguous subarray that has the maximum sum.

Carlos E. R. Alves; Edson Cáceres; Siang W. Song

2004-01-01

107

Functional reach test: movement strategies in diabetic subjects.  

PubMed

Functional reach (FR) is a clinical measure, defined as the maximum distance one can reach, forward beyond arm's length, able to identify elderly subjects at risk of recurrent falls. Subjects, exhibiting the same FR can perform the motor task in different ways: a kinematic analysis of the FR, task can help to identify the motor strategy adopted. The FR test was applied to 17 diabetic non-neuropathic, (CTRL) and 37 neuropathic (DN) subjects. Motor strategies adopted were defined as: "hip" or "other" strategy; the latter included: "mixed" and "trunk rotation" strategies. Principal Component Analysis and non-parametric statistical tests were used to study the different execution modalities of the FR test. Results show that, in CTRL, the most important parameters are those related to trunk flexion in the sagittal plane. Instead, for DN, the main features are related not only to trunk flexion but also to trunk rotation in the transverse plane. Percentages of subjects who used "hip" or "other" strategies are similar for CTRL and DN subjects. However, within the "other" strategy group, the percentage of DN that used a "trunk rotation" strategy was much higher than for CTRL. Results show that individuals, although exhibiting the same reaching distance, adopt different movement strategies. Consequently it is important to evaluate the kinematic behaviour and not only the clinical measure, because the evaluation of the motor strategy might be useful in the early detection of subjects at risk of postural instability. PMID:24074730

Maranesi, Elvira; Ghetti, Giacomo; Rabini, Rosa Anna; Fioretti, Sandro

2014-01-01

108

REACH. Teacher's Guide Volume II. Check Points.  

ERIC Educational Resources Information Center

Designed for use with individualized instructional units (CE 026 345-347, CE 026 349-351) in the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this second volume of the postsecondary teacher guide contains the check points which the instructor may want to refer to when the unit sheet directs the…

Georgia Univ., Athens. Div. of Vocational Education.

109

Flood Hazard Mapping in Lower Reach of  

Microsoft Academic Search

After the Tsunami, disaster management strategies have undergone rapid changes. Flood hazard mapping has, particularly, been realized as one of foremost tasks to be accomplished in support of disaster management and sustainable development. As a pioneering effort, the lower reach of Kelani River which covers the islandís capital, Colombo, and two densely populated districts of the country. Colombo and Gampaha

I. P. Ajith Gunasekara

2008-01-01

110

Science Experiments: Reaching Out to Our Users  

ERIC Educational Resources Information Center

As more users access library services remotely, it has become increasingly important for librarians to reach out to their user communities and promote the value of libraries. Convincing the faculty and students in the sciences of the value of libraries and librarians can be a particularly "hard sell" as more and more of their primary journal…

Nolan, Maureen; Tschirhart, Lori; Wright, Stephanie; Barrett, Laura; Parsons, Matthew; Whang, Linda

2008-01-01

111

Polishing Difficult-To-Reach Cavities  

NASA Technical Reports Server (NTRS)

Springy abrasive tool used to finish surfaces of narrow cavities made by electrical-discharge machining. Robot arm moves vibrator around perimeters of cavities, polishing walls of cavities as it does so. Tool needed because such cavities inaccessible or at least difficult to reach with most surface-finishing tools.

Malinzak, R. Michael; Booth, Gary N.

1990-01-01

112

Project Reach: Final Report--Year 2.  

ERIC Educational Resources Information Center

The second year of Project Reach, a Federally funded two-year program, pursued two tactics for increasing the adult basic education (ABE) program relevance and effectiveness in South Bend, Indiana: (1) the training/hiring of ABE students as media paraprofessionals, and (2) a media enrollment campaign of various media promotions (television/radio…

McClelland, Samuel D.

113

Reaching out: Beyond School Walls. Spotlight Feature  

ERIC Educational Resources Information Center

In this article, the author features ideas and strategies for outreach that librarians can do to promote one's library media program and the good work it does. She stresses that by working together and reaching out, librarians can help foster visibility and support for school library media programs and professionals alike nationwide. Here, she…

Dopke-Wilson, MariRae

2008-01-01

114

REACH. Teacher's Guide, Volume III. Task Analysis.  

ERIC Educational Resources Information Center

Designed for use with individualized instructional units (CE 026 345-347, CE 026 349-351) in the electromechanical cluster, this third volume of the postsecondary teacher's guide presents the task analysis which was used in the development of the REACH (Refrigeration, Electro-Mechanical, Air Conditioning, Heating) curriculum. The major blocks of…

Morris, James Lee; And Others

115

Hydro automation. Rocky Reach hydroelectric project  

Microsoft Academic Search

The author describes how, in 1997, Rocky Reach hydroelectric power plant (USA) became one of the first hydropower projects to use a Windows NT based plant control system with programmable logic controllers (PLCs) controlling the unit auxiliary systems. The new system uses off-the-shelf software and hardware to create an inexpensive yet versatile plant automation system

J. A. Mettler

1999-01-01

116

REINFORCEMENT LEARNING FOR ROBOTIC REACHING AND GRASPING  

Microsoft Academic Search

SUMMARY A reinforcement learning approach is used to train a neural controller to perform a robotic reaching task. Unlike supervised learning techniques, where the teacher must provide the correct sequence of motor actions, only an evaluation of the robot's performance is provided. From this limited information, the robot must discover the appropriate motor programs that best satisfy the teacher's evaluation

A. H. Fagg

1993-01-01

117

Effect of physiological age on growth vigour of seed potatoes of two cultivars. 5. Review of literature and integration of some experimental results  

Microsoft Academic Search

The most important literature on physiological age is discussed and an attempt is made to describe the relationship between the chronological age and growth vigour of seed of cvs. Jaerla and Désirée produced in three seasons and stored at 4 or 12°C in darkness. The seed of both cultivars reaches maximum growth vigour earlier when stored at 12°C, although this

D. E. Van der Zaag; C. D. Van Loon

1987-01-01

118

[Implications of the REACH registry for endocrinologists].  

PubMed

Diabetes mellitus is a major public health problem due to its increasing incidence in the general population and the morbidity and mortality associated with micro- and macrovascular complications. Patients with diabetes have a 2-5-fold increased risk of coronary heart disease, stroke and peripheral artery disease. The REACH registry is the largest observational study in the world designed to assess prognostic and therapeutic data in the population with elevated risk for atherothrombotic events. The results of this study show a high prevalence of obesity, diabetes mellitus and metabolic syndrome in the population with increased cardiovascular risk. Moreover, the data demonstrate that metabolic control of diabetes mellitus is clearly inadequate. Data from the REACH registry show endocrinologists and diabetologists that a multidisciplinary approach is imperative and that adequate management of diabetic patients should include stratification of cardiovascular risk, including assessment of associated conditions such as obesity, hypertension, dyslipidemia, microalbuminuria and smoking. PMID:19631834

Alonso, Guillermo

2009-09-01

119

Bedrock Incision Rates Through A Knickpoint Reach  

NASA Astrophysics Data System (ADS)

Bedrock river incision is a fundamental process in landscape evolution, controlling, for example, the rate at which base-level fall is propagated through the drainage net and hence the rate of sediment flux from source areas to sedimentary basin ­rsinks'. Particular attention has been focused on the processes and erosion rates upstream and downstream of knickpoints. These key bedrock river landforms propagate headwards to transmit the ­rmessage­_ to the drainage net that base-level has fallen. Knickpoints may be sharply defined as waterfalls or cascades, which separate reaches controlled by different environmental settings. They may originate as a result of base-level changes, tectonic uplift, lithologic and structural controls, tributary sediment inputs or environmental changes. Information on changes in bed incision rates through a knickpoint reach provides insight into the role of knickpoints in landscape evolution. The River Etive, Scotland, has alternating alluvial and bedrock reaches and a stepped long profile caused by series of knickpoints. To investigate the controls over bedrock incision in this river, numerical simulations were performed using a process-based incision model. Physical modelling of the impact of bedload on abrasion has been used to verify the numerical simulations and cosmogenic nuclides have been used to estimate incision rates as a final test. To characterise and assess changes in incision rates through the knickpoint reach, five bedrock samples were collected for cosmogenic isotope analysis from above and below a knickpoint in the bed of the River Etive. The samples were taken from as close to the low flow water surface as practically possible and are overtopped even at moderate flows; it is therefore highly unlikely that they have ever been shielded by either peat or alluvial sediment. The sample sites have clearly been fluvially sculpted and are smooth and rounded; they are therefore highly appropriate for the analysis. Quartz was extracted from the samples and fully prepared, following standard procedures. In addition, the overall incision rates in the reach have been estimated using a bedrock incision model. The numerical model, in which incision is dominated by abrasion by saltating sediment particles, shows how interactions between sediment dynamics and hydraulic conditions determine the incision rates. Sensitivity analyses incorporating a wide range of model parameterisations confirmed that erosion rates in bedrock rivers are controlled by stream power, but changes in sediment discharge and size also play important roles in incision. The numerical simulation results are further tested through tumbling mill experiments. Topographic and sedimentological data from the River Etive are used to estimate the erosion rates in the knickpoint reach using the numerical model. The numerical simulations show that the spatial patterns of incision are changed as model parameters are changed. A conventional, diffusion style, model produced declining slopes at knickpoints, while the new model, which incorporates sediment dynamics, produced more complicated pattern of incision. The physical processes operating in knickpoint reaches determined the mode and rate of incision, and these physical processes change with location within the reach. For abrasion, changes in effective sediment flux as transport stage changes plays the critical role in determining incision rates. These conclusions will be evaluated using the cosmogenically derived incision rates.

Kim, J.; Hoey, T.; Bishop, P.; Fifield, K.; Levchenko, V.

2003-12-01

120

Reaching Asian Americans: Sampling Strategies and Incentives  

Microsoft Academic Search

Reaching and recruiting representative samples of minority populations is often challenging. This study examined in Chinese\\u000a and Korean Americans: 1) whether using two different sampling strategies (random sampling vs. convenience sampling) significantly\\u000a affected characteristics of recruited participants and 2) whether providing different incentives in the mail survey produced\\u000a different response rates. We found statistically significant, however mostly not remarkable, differences

Soo-Kyung Lee; Yu-Yao Cheng

2006-01-01

121

A Maximum Likelihood Stereo Algorithm  

Microsoft Academic Search

A stereo algorithm is presented that optimizes a maximum likelihood cost function. The maximum likelihood cost function assumes that corresponding features in the left and right images are normally distributed about a common true value and consists of a weighted squared error term if two features are matched or a (fixed) cost if a feature is determined to be occluded.

Ingemar J. Cox; Sunita L. Hingorani; Satish B. Rao; Bruce M. Maggs

1996-01-01

122

Age-related differences in the reaching and grasping coordination in children: unimanual and bimanual tasks.  

PubMed

This study examined age-related differences in the coordinative mechanism of the reach-to-grasp movement in three groups of children aged 6, 8, and 11 year, and in healthy adults. Three prehension conditions were manipulated: an unimanual and a bimanual self-driven tasks in which the reaching and grasping of the object were performed by participants, and a bimanual externally-driven task, in which the experimenter brought the object into the vicinity of the participant which grasped it. Classical kinematics data-peak velocities of the reaching and the grasping, the time to onset grip opening, maximum grip opening and grip closure-were calculated. Moreover, to obtain equivalent kinematics variables for all age groups, relative time to peak velocity (% of reaching duration), relative maximum grip opening (% of object size), and percentage of the four types of phase plans between reaching velocity and grip size have been calculated for each group of age. Our main results showed (1) a high variability at age 6, (2) an age-related change between the 6- and 8-year old for almost all of the dependent variables, and (3) a significant difference between the 11-year olds and adults. In summary, at 6 years, the interdependence between the reaching and grasping programs was unstable. A transitory feedback-based coordination between reaching and grasping appeared at 8 years of age. Finally, the adults' relationship between reaching and grasping was not attained at the age of 11. PMID:17091289

Olivier, Isabelle; Hay, Laurette; Bard, Chantal; Fleury, Michelle

2007-05-01

123

Prediction of visually perceived location using reaching action and effect of reaching distance on it  

NASA Astrophysics Data System (ADS)

We examined what effect the reaching distance had on the prediction of a visually perceived location using reaching action. A system presenting a virtual object must execute the process of interaction when a body is directly at the visually perceived location of the virtual object to enable direct interaction between an observer's body and the virtual object. Conventional techniques assume that the visually perceived location is the same as the location defined by binocular disparity. However, both locations are often different. We proposed a new technique in our previous studies to predict the visually perceived location using an observer's action. We also demonstrated prediction using an action where an observer reached out to a virtual object. This study was an examination into the range of applications of our proposed approach. An observer in an experiment reached out to a virtual object, and the reaching distance was the experimental variable. The results did not support the effect of the reaching distance on prediction. We demonstrated that our technique could be applied to a wide range of reaching distances.

Suzuki, Masahiro; Takazawa, Keigo; Uehira, Kazutake; Unno, Hiroshi

2012-02-01

124

Riparian Vegetation Mapping Along the Hanford Reach  

SciTech Connect

During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002 to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer.

FOGWELL, T.W.

2003-07-11

125

Medium for Isolation and Growth of Bacteria Associated with Plum Leaf Scald and Phony Peach Diseases  

PubMed Central

Rickettsia-like bacteria associated with plum leaf scald and phony peach diseases were isolated from diseased but not from healthy tissues and cultured on charcoal-yeast extract medium (BCYE) buffered with ACES (2-[(2-amino-2-oxoethyl) amino]-ethanesulfonic acid). Optimum conditions for isolation and growth on BCYE medium were pH 6.5 to 6.9 at 20 and 25°C under normal atmosphere. Growth of primary colonies and first-passage subcultures was restricted, and colonies reached a maximum diameter of 0.6 mm in 60 days. After 12 passages, subcultures reached maximum growth in 21 days. The rickettsia-like bacteria from BCYE cultures were gram negative, serologically the same as those present in diseased peach and plum, and composed of rod-shaped cells measuring 0.35 by 5 ?m (average diameter and maximum length) in a matrix of filamentous strands of similar width but of variable length. Images

Wells, J. M.; Raju, B. C.; Nyland, G.; Lowe, S. K.

1981-01-01

126

Spallation Neutron Source reaches megawatt power  

SciTech Connect

The Department of Energy's Spallation Neutron Source (SNS), already the world's most powerful facility for pulsed neutron scattering science, is now the first pulsed spallation neutron source to break the one-megawatt barrier. "Advances in the materials sciences are fundamental to the development of clean and sustainable energy technologies. In reaching this milestone of operating power, the Spallation Neutron Source is providing scientists with an unmatched resource for unlocking the secrets of materials at the molecular level," said Dr. William F. Brinkman, Director of DOE's Office of Science.

Dr. William F. Brinkman

2009-09-30

127

Feldenkrais sensory imagery and forward reach.  

PubMed

To investigate the effect of sensory imagery on subsequent movement, a unilateral Fleldenkrais lesson of imaging a soft bristle brush passing over one half of the body and in which no movement occurred, was given to 12 naive subjects. Forward flexion for each side of the body was measured at a sit-and-reach box. For 8 and 10 subjects who reported the perception of a side as being longer and lighter following the sensory imagery, there was also a significant increase in the forward flexion range on that side. PMID:11153843

Dunn, P A; Rogers, D K

2000-12-01

128

Arctic Sea Ice Maximum 2011  

NASA Video Gallery

AMSR-E Arctic Sea Ice: September 2010 to March 2011: Scientists tracking the annual maximum extent of Arctic sea ice said that 2011 was among the lowest ice extents measured since satellites began ...

129

Contribution of Mycorrhizae to Early Growth and Phosphorus Uptake by a Neotropical Palm  

Microsoft Academic Search

Arbuscular mycorrhizal fungi (AMF) can act as an extension of the root system of their host plants. In Desmoncus orthacanthos Martius (Arecaceae), which has thick and unbranched roots (i.e., magnolioid roots) and low densities of root hairs, this association may be essential to reach a maximum growth with minimum fertilizers. This is important because of the potential in the south

José Ramos-Zapata; Roger Orellana; Patricia Guadarrama; Salvador Medina-Peralta

2009-01-01

130

Can donated media placements reach intended audiences?  

PubMed

Donated media placements for public service announcements (PSAs) can be difficult to secure, and may not always reach intended audiences. Strategies used by the Centers for Disease Control and Prevention's (CDC) Screen for Life: National Colorectal Cancer Action Campaign (SFL) to obtain donated media placements include producing a diverse mix of high-quality PSAs, co-branding with state and tribal health agencies, securing celebrity involvement, monitoring media trends to identify new distribution opportunities, and strategically timing the release of PSAs. To investigate open-ended recall of PSAs promoting colorectal cancer screening, CDC conducted 12 focus groups in three U.S. cities with men and women either nearing age 50 years, when screening is recommended to begin, or aged 50-75 years who were not in compliance with screening guidelines. In most focus groups, multiple participants recalled exposure to PSAs promoting colorectal cancer screening, and most of these individuals reported having seen SFL PSAs on television, in transit stations, or on the sides of public buses. Some participants reported exposure to SFL PSAs without prompting from the moderator, as they explained how they learned about the disease. Several participants reported learning key campaign messages from PSAs, including that colorectal cancer screening should begin at age 50 years and screening can find polyps so they can be removed before becoming cancerous. Donated media placements can reach and educate mass audiences, including millions of U.S. adults who have not been screened appropriately for colorectal cancer. PMID:23720533

Cooper, Crystale Purvis; Gelb, Cynthia A; Chu, Jennifer; Polonec, Lindsey

2013-09-01

131

Planets Beyond the Reach of Kepler - Introduction  

NASA Astrophysics Data System (ADS)

What kind of planets lie at orbit radii of 1-2 AU - beyond the reach of Kepler? In the last two decades we have explored a sample of RV-detected planets, discovered distant planets with microlensing, and several hot young planets at large radii have been detected by direct imaging, as well as the debris disks that provide clues to formation and evolution. In these 4 sessions, we explore the near future, and how we can expect to learn much more about the demographics and properties of cold outer planets. AFTA-WFIRST will open up this area, with a microlensing survey to probe the population of long-orbit planets, and coronagraphy to take images and spectra of large planets in orbits at a few AU.

Unwin, Stephen C.

2014-06-01

132

Reach and get capability in a computing environment  

SciTech Connect

A reach and get technique includes invoking a reach command from a reach location within a computing environment. A user can then navigate to an object within the computing environment and invoke a get command on the object. In response to invoking the get command, the computing environment is automatically navigated back to the reach location and the object copied into the reach location.

Bouchard, Ann M. (Albuquerque, NM); Osbourn, Gordon C. (Albuquerque, NM)

2012-06-05

133

Effects of different movement strategies on forward reach distance  

Microsoft Academic Search

The functional reach test (FRT) is a reliable and frequently used test to measure dynamic balance ability clinically. However, it is not clear if reach strategy would affect the association between reach distance and dynamic balance. The purpose of this study was to investigate the extent to which reach distance reflected dynamic balance in different reaching strategies. Thirty-three healthy young

Chien-Fen Liao; Sang-I. Lin

2008-01-01

134

Project Outreach: Organizations Unified to Reach Youth.  

PubMed

Youths of today are forced to deal with the external pressures of alcohol and drug abuse on all levels-from the older youngsters across the street pressuring them to be "cool," to the "cute dog" enticing them with the glamour of being the original "party animal." Through today's mass communications, young people are exposed to negative, self-destructive attitudes. It is important, therefore, to expose them to a more positive influence and try to reach them through parental guidance, personal contact, and peer pressure. To achieve this, the University of Missouri's Kansas City Chapter of the American Pharmaceutical Association's Academy of Students of Pharmacy, in conjunction with the Metropolitan Kansas City Area Task Force on Alcohol and Other Drug Abuse, proposed the development of an annual drug abuse prevention program that specifically targets fifth graders in the greater Kansas City metropolitan area. A primary goal of Project Outreach (Organizations Unified to Reach Youth) is to unite drug abuse prevention programs in the greater Kansas City metropolitan area in their outreach efforts to give positive support to Kansas City's youth against alcohol and other drugs. Phase I of Project Outreach consisted of a series of programs for the parents in the community. Phase II entailed college students who spoke to fifth graders in their classrooms. These students also participated in poster and poem contents centered around drug abuse prevention. In Phase III, which featured an outstanding, motivated speaker, the sample group of 600 fifth graders in the area participated in a major event to give positive peer pressure to say no to drugs. Pertinent entertainment also was provided, and the governor of Missouri, John Ashcroft, attended the rally. In the future, each fifth grader will receive a free T-shirt as a tangible reminder of the main event. In Phase IV, to reinforce concepts presented in previous programming, the college students returned to the fifth grade classrooms to speak. Project Outreach programs are incorporated into existing drug abuse prevention programs and provide the foundation for the development of new drug abuse prevention programs in the greater Kansas City metropolitan area. PMID:2493666

Dunnington, B C; Hayes, M L

1989-01-01

135

Gaussian Prior for Smoothing Maximum Entropy Models.  

National Technical Information Service (NTIS)

In certain contexts, maximum entropy (ME) modeling can be viewed as maximum likelihood training for exponential models, and like other maximum likelihood methods is prone to overfitting of training data. Several smoothing methods for maximum entropy model...

S. F. Chen R. Rosenfeld

1999-01-01

136

Growth Kinetics and Toxicity of Enterobacter cloacae Grown on Linear Alkylbenzene Sulfonate as Sole Carbon Source  

Microsoft Academic Search

A successful attempt was made to isolate linear alkylbenzene sulfonate (LAS)–degrading bacteria from soil irrigated with wastewater.\\u000a The isolated bacteria were able to use LAS as sole carbon and energy source. Maximum growth rates on LAS reached only 0.27 h?1. 16S-rRNA sequencing and fatty-acid analysis placed the bacteria in the genus Enterobacter cloacae. The growth curves of E. cloacae both in

Khaled M. Khleifat; Khaled A. Tarawneh; Mohammad Ali Wedyan; Amjad A. Al-Tarawneh; Khalid Al Sharafa

2008-01-01

137

Kinetics of ? 5,7 -sterol accumulation during growth of Saccharomyces cerevisiae  

Microsoft Academic Search

Saccharomyces cerevisiae accumulates ?5,7-sterols up to 4 mg per g biomass. The differential rate of sterol synthesis continually increases during growth, its value\\u000a only being decreased at sterol levels higher than 30 mg per g biomass. The specific rate of sterol synthesis reaches a broad\\u000a maximum during the growth phase. The gradual sterol accumulation pattern is dominant in cultures growing

?. Novotný; B. B?halová; L. Doležalová; J. Zají?ek

1987-01-01

138

Using New Media to Reach Broad Audiences  

NASA Astrophysics Data System (ADS)

The International Year of Astronomy New Media Working Group (IYA NMWG) has a singular mission: To flood the Internet with ways to learn about astronomy, interact with astronomers and astronomy content, and socially network with astronomy. Within each of these areas, we seek to build lasting programs and partnerships that will continue beyond 2009. Our weapon of choice is New Media. It is often easiest to define New Media by what it is not. Television, radio, print and their online redistribution of content are not New Media. Many forms of New Media start as user provided content and content infrastructures that answer that individual's creative whim in a way that is adopted by a broader audience. Classic examples include Blogs and Podcasts. This media is typically distributed through content specific websites and RSS feeds, which allow syndication. RSS aggregators (iTunes has audio and video aggregation abilities) allow subscribers to have content delivered to their computers automatically when they connect to the Internet. RSS technology is also being used in such creative ways as allowing automatically updating Google-maps that show the location of someone with an intelligent GPS system, and in sharing 100 word microblogs from anyone (Twitters) through a single feed. In this poster, we outline how the IYA NMWG plans to use New Media to reach target primary audiences of astronomy enthusiasts, image lovers, and amateur astronomers, as well as secondary audiences, including: science fiction fans, online gamers, and skeptics.

Gay, P. L.

2008-06-01

139

Assessment of reproductive toxicity under REACH.  

PubMed

The European REACH regulation requires the evaluation of reproductive toxicity in screening tests according to OECD TG 421 and 422 for substances above the tonnage level of 10 tons/year. The overall aim of this paper is to increase flexibility in combination with a reduced number of experimental animals. Therefore, in contrast to the existing approach the registrant should have the possibility to file a dossier for a substance at the level of 10 tons/year and above also on the basis of data from a developmental toxicity study (OECD TG 414) plus a full-scale subacute toxicity study (OECD TG 407 according to the 1995 protocol). The proposed new test strategy takes into account overall considerations of duty of care and animal welfare. It enables an assessment of developmental toxicity on a definitive instead of a screening level. Registrants should be allowed to select between these two options, either the existing approach (OECD TG 421/407 and alternatively TG 422) or the approach proposed in this paper (OECD TG 407 plus TG 414). PMID:22475931

Aulmann, Walter

2012-07-01

140

Media perspective - new opportunities for reaching audiences  

NASA Astrophysics Data System (ADS)

The world of media is experiencing a period of extreme and rapid change with the rise of internet television and the download generation. Many young people no longer watch standard TV. Instead, they go on-line, talking to friends and downloading pictures, videos, music clips to put on their own websites and watch/ listen to on their laptops and mobile phones. Gone are the days when TV controllers determined what you watched and when you watched it. Now the buzzword is IPTV, Internet Protocol Television, with companies such as JOOST offering hundreds of channels on a wide range of subjects, all of which you can choose to watch when and where you wish, on your high-def widescreen with stereo surround sound at home or on your mobile phone on the train. This media revolution is changing the way organisations get their message out. And it is encouraging companies such as advertising agencies to be creative about new ways of accessing audiences. The good news is that we have fresh opportunities to reach young people through internet-based media and material downloaded through tools such as games machines, as well as through the traditional media. And it is important for Europlanet to make the most of these new and exciting developments.

Haswell, Katy

2007-08-01

141

Tobacco Companies, State Attorneys Reach Settlement  

NSDL National Science Digital Library

This week's In the News examines the November 16, 1998 $206 billion settlement reached between tobacco industry leaders and eight US states. The twelve resources discussed provide press releases, opinion, and background information on the economics of tobacco production and consumption in the US. Following increasing pressure from anti-tobacco activists at the state level, Philip Morris Incorporated, R.J. Reynolds Tobacco Company, Brown & Williamson Tobacco Corporation, and the Lorillard Tobacco Company settled pending lawsuits with New York, California, and Wisconsin, among other states. The agreement requires the companies to pay the potential medical costs of sick smokers based on a formula that factors state-by-state population, tobacco use, and previous Medicaid cost. The agreement also provides for a $1.5 billion anti-smoking campaign fund and bans billboard and transit ads in addition to "branded" merchandising -- the sale and distribution of items bearing tobacco brands' names or logos. Although these provisions give anti-smoking organizations much needed funding for educational resources, critics fear that the settlement protects the tobacco industry more than it hinders it. According to Gary Black, an analyst at Sanford C. Bernstein & Co., the settlement "removes the remaining threat of bankruptcy from the stocks and reduces the litigation discount that has plagued tobacco companies since 1994." With little risk of future lawsuits according to Black, "we're back to business as usual."

Waters, Megan.

1998-01-01

142

Sensitivity to prediction error in reach adaptation  

PubMed Central

It has been proposed that the brain predicts the sensory consequences of a movement and compares it to the actual sensory feedback. When the two differ, an error signal is formed, driving adaptation. How does an error in one trial alter performance in the subsequent trial? Here we show that the sensitivity to error is not constant but declines as a function of error magnitude. That is, one learns relatively less from large errors compared with small errors. We performed an experiment in which humans made reaching movements and randomly experienced an error in both their visual and proprioceptive feedback. Proprioceptive errors were created with force fields, and visual errors were formed by perturbing the cursor trajectory to create a visual error that was smaller, the same size, or larger than the proprioceptive error. We measured single-trial adaptation and calculated sensitivity to error, i.e., the ratio of the trial-to-trial change in motor commands to error size. We found that for both sensory modalities sensitivity decreased with increasing error size. A reanalysis of a number of previously published psychophysical results also exhibited this feature. Finally, we asked how the brain might encode sensitivity to error. We reanalyzed previously published probabilities of cerebellar complex spikes (CSs) and found that this probability declined with increasing error size. From this we posit that a CS may be representative of the sensitivity to error, and not error itself, a hypothesis that may explain conflicting reports about CSs and their relationship to error.

Haith, Adrian M.; Harran, Michelle D.; Shadmehr, Reza

2012-01-01

143

Maximum Acceptable Weight of Lift  

Microsoft Academic Search

This paper discusses the maximum amount of weight that an individual can be expected to lift comfortably and without strain. Recommendations based on empirical estimates, biomechanical techniques, and psychophysical methods are reviewed, including those of the International Labour Office, the Swiss Accident Insurance Institute, the Danish National Association for Infantile Paralysis, and the U. S. Air Force. The approach used

S. H. Snook; C. H. Irvine

1967-01-01

144

Graphs with maximum connectivity index  

Microsoft Academic Search

Let G be a graph and dv the degree (=number of first neighbors) of its vertex v. The connectivity index of G is ?=?(dudv)?1\\/2, with the summation ranging over all pairs of adjacent vertices of G. In a previous paper (Comput. Chem. 23 (1999) 469), by applying a heuristic combinatorial optimization algorithm, the structure of chemical trees possessing extremal (maximum

Gilles Caporossi; Ivan Gutman; Pierre Hansen; Ljiljana Pavlovic

2003-01-01

145

Reaching site closure for groundwater under multiple regulatory agencies  

SciTech Connect

Groundwater at the Connecticut Yankee Atomic Power Company (CYAPCO) Haddam Neck Plant (HNP) has been impacted by both radionuclides and chemical constituents. Furthermore, the cleanup standards and closure requirements for HNP are regulated both by federal and state agencies. The only consistent requirement is the development of a site conceptual model and an understanding of the hydrogeologic conditions that will govern contaminant transport and identify potential receptors. The cleanup criteria to reach site closure for radionuclides is regulated by both the Nuclear Regulatory Commission (NRC) and the Connecticut Department of Environmental Protection (CTDEP) Bureau of Air Management, Radiological Division. For license termination under the NRC, the total effective dose equivalent (TEDE) for all media can not exceed 25 milli-Rem per year (mRem/yr) plus As Low as Reasonably Achievable (ALARA). The CTDEP has a similar requirement with the TEDE not to exceed 19 mRem/yr plus ALARA. To reach these criteria, derived concentration guideline levels (DCGLs) were developed for radiological exposures from three (3) media components; soil, existing groundwater and future groundwater from left-in place foundations or footings. Based on current conditions, the target dose contribution from existing and future groundwater is not to exceed 2 mRem/yr TEDE. After source (soil) remediation is complete, the NRC requires two (2) years of quarterly monitoring to demonstrate that groundwater quality meets the DCGLs and does not show an upward trend. CYAPCO's NRC License Termination Plan (LTP) specifies a minimum 18-month period of groundwater monitoring, as long as samples are collected during two spring/high water seasons, to verify the efficacy of remedial actions at HNP. In addition to the 19 mRem/yr criteria, the CTDEP also requires groundwater to be in compliance with the Remediation Standards Regulation (RSRs). There are no published criteria for radionuclides in the RSRs, however CTDEP has approved the United States Environmental Protection Agency's (USEPA's) Maximum Contaminant Levels (MCLs) as the clean up standards for individual constituents. After remediation of an identified contamination source, the RSRs require that at least one groundwater monitoring well, hydraulically down-gradient of the remediation area, be sampled to confirm that the remediation has not impacted groundwater quality. After four quarters of groundwater monitoring with results below the MCLs, additional groundwater sampling must continue for up to three years to reach site closure in accordance with the RSRs. The cleanup criteria for chemical constituents, including boron, are regulated by the USEPA under the Resource Conservation and Recovery Act (RCRA) and the CTDEP Bureau of Water Protection and Land Reuse. The USEPA, however, has accepted the CTDEP RSRs as the cleanup criteria for RCRA. Therefore attainment of the CTDEP RSRs is the only set of criteria needed to reach closure, but both agencies retain oversight, interpretation, and closure authority. As stated above, under the RSRs, groundwater must be monitored following a source remediation for a minimum of four quarters. After demonstrating that the remediation was successful, then additional groundwater sampling is required for up to three additional years. However, the number of monitoring wells and frequency of sampling are not defined in the RSRs and must be negotiated with CTDEP. To successfully reach closure, the conceptual site model, groundwater transport mechanisms, and potential receptors must be defined. Once the hydrogeology is understood, a long term groundwater monitoring program can then be coordinated to meet each agencies requirement to both terminate the NRC license and reach site closure under RCRA. (authors)

Glucksberg, N. [MACTEC, Inc., Portland, ME (United States); Couture, B. [Connecticut Yankee Atomic Power Company, East Ham (United States)

2007-07-01

146

Cell cycle checkpoint regulators reach a zillion  

PubMed Central

Entry into mitosis is regulated by a checkpoint at the boundary between the G2 and M phases of the cell cycle (G2/M). In many organisms, this checkpoint surveys DNA damage and cell size and is controlled by both the activation of mitotic cyclin-dependent kinases (Cdks) and the inhibition of an opposing phosphatase, protein phosphatase 2A (PP2A). Misregulation of mitotic entry can often lead to oncogenesis or cell death. Recent research has focused on discovering the signaling pathways that feed into the core checkpoint control mechanisms dependent on Cdk and PP2A. Herein, we review the conserved mechanisms of the G2/M transition, including recently discovered upstream signaling pathways that link cell growth and DNA replication to cell cycle progression. Critical consideration of the human, frog and yeast models of mitotic entry frame unresolved and emerging questions in this field, providing a prediction of signaling molecules and pathways yet to be discovered.

Yasutis, Kimberly M.; Kozminski, Keith G.

2013-01-01

147

Cell cycle checkpoint regulators reach a zillion.  

PubMed

Entry into mitosis is regulated by a checkpoint at the boundary between the G2 and M phases of the cell cycle (G2/M). In many organisms, this checkpoint surveys DNA damage and cell size and is controlled by both the activation of mitotic cyclin-dependent kinases (Cdks) and the inhibition of an opposing phosphatase, protein phosphatase 2A (PP2A). Misregulation of mitotic entry can often lead to oncogenesis or cell death. Recent research has focused on discovering the signaling pathways that feed into the core checkpoint control mechanisms dependent on Cdk and PP2A. Herein, we review the conserved mechanisms of the G2/M transition, including recently discovered upstream signaling pathways that link cell growth and DNA replication to cell cycle progression. Critical consideration of the human, frog and yeast models of mitotic entry frame unresolved and emerging questions in this field, providing a prediction of signaling molecules and pathways yet to be discovered. PMID:23598718

Yasutis, Kimberly M; Kozminski, Keith G

2013-05-15

148

Reaching Healthy People 2010 by 2013  

PubMed Central

Background Healthy People 2010 (HP 2010) set as a goal to reduce adult smoking prevalence to 12% by 2010. Purpose This paper uses simulation modeling to examine the effects of three tobacco control policies and cessation treatment policies—alone and in conjunction—on population smoking prevalence. Methods Building on previous versions of the SimSmoke model, the effects of a defined set of policies on quit attempts, treatment use, and treatment effectiveness are estimated as potential levers to reduce smoking prevalence. The analysis considers the effects of (1) price increases through cigarette tax increases, (2) smokefree indoor air laws, (3) mass media/educational policies, and (4) evidence-based and promising cessation treatment policies. Results Evidence-based cessation treatment policies have the strongest effect, boosting the population quit rate by 78.8% in relative terms. Treatment policies are followed by cigarette tax increases (65.9%), smokefree air laws (31.8%), and mass media/educational policies (18.2%). Relative to the status quo in 2020, the model projects that smoking prevalence is reduced by 14.3% by a nationwide tax increase of $2.00, by 7.2% by smokefree laws, by 4.7% by mass media/educational policies, and by 16.5% by cessation treatment policies alone. Implementing all of the above policies in tandem would increase the quit rate by 296% such that the HP 2010 smoking prevalence goal of 12% is reached by 2013. Conclusions The impact of a combination of policies led to some surprisingly optimistic possible futures in lowering smoking prevalence to 12% within just several years. Simulation models can be a useful tool to evaluate complex scenarios where policies are implemented in tandem and for which there are limited data.

Levy, David T.; Mabry, Patricia L.; Graham, Amanda L.; Orleans, C. Tracy; Abrams, David B.

2010-01-01

149

Population Growth  

NSDL National Science Digital Library

These activities explore population growth rates and its consequences with regard to the distribution of natural resources. Population growth is perhaps the most important environmental issue of our time. As population increases and as people seek to raise their standard of living, more stress is put on our earthâs finite resources.One aspect of the population issue is the sheer magnitude of the numbers involved. World population did not reach 1 billion until the year 1800. Since then it has grown exponentially to reach our current 6.7 billion.

2009-01-01

150

Growth of Phragmites australis and Phalaris arundinacea in constructed wetlands for wastewater treatment in the Czech Republic  

Microsoft Academic Search

Common reed (Phragmites australis) and reed canarygrass (Phalaris arundinacea) are two most commonly used plant species in constructed wetlands for wastewater treatment in the Czech Republic. Growth characteristics of both plants (biomass, stem count, and length) have been measured in 13 horizontal sub-surface flow constructed wetlands since 1992. The results revealed that while Phalaris usually reaches its maximum biomass as

Jan Vymazal; Lenka Kr?pfelová

2005-01-01

151

Solar maximum: Solar array degradation  

NASA Technical Reports Server (NTRS)

The 5-year in-orbit power degradation of the silicon solar array aboard the Solar Maximum Satellite was evaluated. This was the first spacecraft to use Teflon R FEP as a coverglass adhesive, thus avoiding the necessity of an ultraviolet filter. The peak power tracking mode of the power regulator unit was employed to ensure consistent maximum power comparisons. Telemetry was normalized to account for the effects of illumination intensity, charged particle irradiation dosage, and solar array temperature. Reference conditions of 1.0 solar constant at air mass zero and 301 K (28 C) were used as a basis for normalization. Beginning-of-life array power was 2230 watts. Currently, the array output is 1830 watts. This corresponds to a 16 percent loss in array performance over 5 years. Comparison of Solar Maximum Telemetry and predicted power levels indicate that array output is 2 percent less than predictions based on an annual 1.0 MeV equivalent election fluence of 2.34 x ten to the 13th power square centimeters space environment.

Miller, T.

1985-01-01

152

Constitutional supercooling in heavily As-doped Czochralski Si crystal growth  

NASA Astrophysics Data System (ADS)

Heavily arsenic (As) doped Si crystals were grown by the Czochralski (CZ) method, and constitutional supercooling in As-doped CZ–Si crystal growth was investigated. When the As concentration in the crystal was high, cellular growth was induced and SiAs precipitates were then observed following the cellular structure. The As concentration increases in the cellular structure along the growth direction and around the precipitates it reaches approximately 4 at%, which corresponds to the maximum solid solubility of As in Si. According to the estimation of critical growth conditions for constitutional supercooling, it qualitatively obeys the theoretical equation of constitutional supercooling.

Taishi, Toshinori; Ohno, Yutaka; Yonenaga, Ichiro

2014-05-01

153

XMM classroom competitions : reaching for the stars!  

NASA Astrophysics Data System (ADS)

Partnered by a unique education network 'European Schoolnet'(*), ESA is today launching these three competitions for schools (age range: 8 to final year) in its Member States: draw a telescope, describe the benefits of space-based astronomy or produce an astronomy observation proposal. Details can be found on the special competition website : http://sci.esa.int/xmm/competition "Draw me a telescope!" This competition for 8 to 12 year-olds asks the class to draw a telescope (inside a 20 - 50 cm diameter circle). The 14 winning entries, one per Member State, will be included in a specially-designed official XMM mission logo to go on the Ariane-5 launcher fairing for official unveiling on launch day. A representative of each winning class will be invited to Kourou for the launch. Deadline for entries : 8 October 1999. For full information on how to enter see : http://sci.esa.int/xmm/competition "What's new, Mr Galileo?" The essay competition for 13 to 15 year-olds challenges an English class, writing in the international language of space, to submit a single page (500 words maximum) description of space-based astronomy and its benefits for humanity. The 14 winners, one per Member States, will be invited to Kourou to visit the Guiana Space Centre, Europe's spaceport, and witness final XMM launch preparations. Deadline for entries : 15 October 1999. For full information on how to enter see : http://sci.esa.int/xmm/competition. "Stargazing" In the final-year class competition, ESA is providing a unique opportunity to use the XMM telescope. Here, the physics class, assisted by the scientific community, has to submit an observation project. The 14 winning proposals will be put into practice in 2000 at a summer camp. Further details will be announced once XMM is in orbit. Note to editors: The X-ray Multi-Mirror mission is the second Cornerstone of ESA's Horizon 2000 Plus science programme. The telescope will revolutionise cosmic X-ray astronomy by harvesting far more X-rays per hour than any previous mission. Its large effective collecting area (120 m2 of mirror, 4500 cm2 of X-ray collecting area) and highly eccentric orbit will allow long-duration observation of unprecedented sensitivity. This enormous capability will enable astronomers to analyse many strong sources of cosmic X-rays very quickly and also discover and characterise many faint sources.

1999-09-01

154

The efficiency of electrokinetic pumping at a condition of maximum.  

SciTech Connect

Numerical methods are employed to examine the work, electric power input, and efficiency of electrokinetic pumps at a condition corresponding to maximum pump work. These analyses employ the full Poisson-Boltzmann equations and account for both convective and conductive electric currents, including surface conductance. We find that efficiencies at this condition of maximum work depend on three dimensionless parameters, the normalized zeta potential, normalized Debye layer thickness, and a fluid property termed the Levine number indicating the nominal ratio of convective to conductive electric currents. Efficiencies at maximum work exhibit a maximum for an optimum Debye layer thickness when the zeta potential and Levine number are fixed. This maximum efficiency increases with the square of the zeta potential when the zeta potential is small, but reaches a plateau as the zeta potential becomes large. The maximum efficiency in this latter regime is thus independent of the zeta potential and depends only on the Levine number. Simple analytical expressions describing this maximum efficiency in terms of the Levine number are provided. Geometries of a circular tube and planar channel are examined.

Griffiths, Stewart K.; Nilson, Robert H.

2004-08-01

155

Maximum life spur gear design  

NASA Technical Reports Server (NTRS)

Optimization procedures allow one to design a spur gear reduction for maximum life and other end use criteria. A modified feasible directions search algorithm permits a wide variety of inequality constraints and exact design requirements to be met with low sensitivity to initial guess values. The optimization algorithm is described, and the models for gear life and performance are presented. The algorithm is compact and has been programmed for execution on a desk top computer. Two examples are presented to illustrate the method and its application.

Savage, M.; Mackulin, M. J.; Coe, H. H.; Coy, J. J.

1991-01-01

156

Linear time maximum margin clustering.  

PubMed

Maximum margin clustering (MMC) is a newly proposed clustering method which has shown promising performance in recent studies. It extends the computational techniques of support vector machine (SVM) to the unsupervised scenario. Traditionally, MMC is formulated as a nonconvex integer programming problem which makes it difficult to solve. Several methods have been proposed in the literature to solve the MMC problem based on either semidefinite programming (SDP) or alternating optimization. However, these methods are still time demanding when handling large scale data sets, which limits its application in real-world problems. In this paper, we propose a cutting plane maximum margin clustering (CPMMC) algorithm. It first decomposes the nonconvex MMC problem into a series of convex subproblems by making use of the constrained concave-convex procedure (CCCP), then for each subproblem, our algorithm adopts the cutting plane algorithm to solve it. Moreover, we show that the CPMMC algorithm takes O(sn) time to converge with guaranteed accuracy, where n is the number of samples in the data set and s is the sparsity of the data set, i.e., the average number of nonzero features of the data samples. We also derive the multiclass version of our CPMMC algorithm. Experimental evaluations on several real-world data sets show that CPMMC performs better than existing MMC methods, both in efficiency and accuracy. PMID:20083456

Wang, Fei; Zhao, Bin; Zhang, Changshui

2010-02-01

157

High-speed long-reach wavelength-division-multiplexed passive optical network architectures  

NASA Astrophysics Data System (ADS)

We evaluate the performance of wavelength-locked Fabry-Pérot laser diode and spectrum-sliced ASE source for a high-speed (beyond 1.25 Gb/s) signal transmission in wavelength-division-multiplexed passive optical networks (WDM PONs). The impacts of relative intensity noise and fiber chromatic dispersion on the system performance are mainly investigated. In addition, we analyze the maximum reach of our proposed long-reach WDM PON architecture which utilize the distributed Raman amplification and pump recycling technique.

Kim, Chul Han

2007-10-01

158

Cancer costs projected to reach at least $158 billion in 2020;  

Cancer.gov

Based on growth and aging of the U.S. population, medical expenditures for cancer in the year 2020 are projected to reach at least $158 billion (in 2010 dollars) – an increase of 27 percent over 2010, according to a National Institutes of Health analysis.

159

Coral mortality increases wave energy reaching shores protected by reef flats: Examples from the Seychelles  

Microsoft Academic Search

In the granitic Seychelles, many shores and beaches are fringed by coral reef flats which provide protection to shores from erosion by waves. The surfaces of these reef flats support a complex ecology. About 10 years ago their seaward zones were extensively covered by a rich coral growth, which reached approximately to mean low water level, but in 1998 this

Charles Sheppard; David J. Dixon; Michael Gourlay; Anne Sheppard; Rolph Payet

2005-01-01

160

Role of peripheral vision in rapid perturbation-evoked reach-to-grasp reactions.  

PubMed

Onset and execution of compensatory reaches are faster than the most rapid voluntary reaches. With onset latencies near 100 ms, it is proposed that initial control of compensatory reaches cannot rely on visual information obtained after perturbation onset; rather, they rely on a visuospatial map acquired prior to instability. In natural conditions, it is not practical to direct gaze toward every potential support surface in preparation for a perturbation, suggesting that peripheral vision may be uniquely important. This study aimed to determine whether visuospatial mapping achieved using only peripheral visual information could be used to control reach-to-grasp reactions. Participants sat in an unstable chair. Whole body perturbations were used to evoke rapid reach-to-grasp reactions. A handle was positioned at midline or to the right of the participant. Gaze was directed toward the center or right to view the handle in peripheral or central visual fields. Electromyographic and kinematic data were recorded. Peripheral information acquired prior to perturbation was sufficient for successful execution of reach-to-grasp without delay. Differences in reach kinematics, however, did exist between vision conditions (e.g., maximum lateral wrist displacement and magnitude of hand overshoot relative to the handle were greater for peripheral vs. central vision). Handle location led to target-specific differences in initial muscle recruitment revealing information acquired prior to perturbation were used to guide initial limb trajectory. Results reveal the capacity to rely on a visuospatial map constructed from peripheral visual information for compensatory reaching but also highlight limitations leading to more conservative reach trajectories. PMID:23811736

Akram, Sakineh B; Miyasike-daSilva, Veronica; Van Ooteghem, Karen; McIlroy, William E

2013-09-01

161

Reaching Hard-to-Reach Individuals: Nonselective Versus Targeted Outbreak Response Vaccination for Measles  

PubMed Central

Current mass vaccination campaigns in measles outbreak response are nonselective with respect to the immune status of individuals. However, the heterogeneity in immunity, due to previous vaccination coverage or infection, may lead to potential bias of such campaigns toward those with previous high access to vaccination and may result in a lower-than-expected effective impact. During the 2010 measles outbreak in Malawi, only 3 of the 8 districts where vaccination occurred achieved a measureable effective campaign impact (i.e., a reduction in measles cases in the targeted age groups greater than that observed in nonvaccinated districts). Simulation models suggest that selective campaigns targeting hard-to-reach individuals are of greater benefit, particularly in highly vaccinated populations, even for low target coverage and with late implementation. However, the choice between targeted and nonselective campaigns should be context specific, achieving a reasonable balance of feasibility, cost, and expected impact. In addition, it is critical to develop operational strategies to identify and target hard-to-reach individuals.

Minetti, Andrea; Hurtado, Northan; Grais, Rebecca F.; Ferrari, Matthew

2014-01-01

162

Reach and its Impact: NASA and US Aerospace Communities  

NASA Technical Reports Server (NTRS)

REACH is a European law that threatens to impact materials used within the US aerospace communities, including NASA. The presentation briefly covers REACH and generally, its perceived impacts to NASA and the aerospace community within the US.

Rothgeb, Matthew J.

2011-01-01

163

Effects of different movement strategies on forward reach distance.  

PubMed

The functional reach test (FRT) is a reliable and frequently used test to measure dynamic balance ability clinically. However, it is not clear if reach strategy would affect the association between reach distance and dynamic balance. The purpose of this study was to investigate the extent to which reach distance reflected dynamic balance in different reaching strategies. Thirty-three healthy young adults performed the FRT that required subjects to stand with the feet shoulder width apart and one arm raised to 90 degrees , and then reach forward as far as possible without moving the feet or losing balance. Two additional instructions were given to induce different strategies: keeping the raised arm at 90 degrees throughout the test, and reaching toward a shoulder-height target. The kinematics was recorded using a Vicon motion system, and the hip, ankle and mixed strategies were identified. The results showed that subjects adopted different strategies during the FRT. Significant correlations were found between reach distance and center of mass displacement in the ankle, and mixed strategies. Reach distance, hip posterior displacement and angular displacement of the trunk, hip and ankle were significantly different between the hip and ankle strategies. These findings show that the extent to which reach distance reflected dynamic balance was affected by the reach strategy adopted. It is suggested that clinically, both reach distance and movement patterns should be given special attention when conducting the FRT. PMID:17988869

Liao, Chien-Fen; Lin, Sang-I

2008-07-01

164

Suspended Sediment Transport in the Freshwater Reach of the Hudson River Estuary in Eastern New York  

Microsoft Academic Search

Deposition of Hudson River sediment into New York Harbor interferes with navigation lanes and requires continuous dredging.\\u000a Sediment dynamics at the Hudson estuary turbidity maximum (ETM) have received considerable study, but delivery of sediment\\u000a to the ETM through the freshwater reach of the estuary has received relatively little attention and few direct measurements.\\u000a An acoustic Doppler current profiler was positioned

G. R. Wall; E. A. Nystrom; S. Litten

2008-01-01

165

The maximum drag reduction asymptote  

NASA Astrophysics Data System (ADS)

Addition of a small amount of long chain polymers to a Newtonian solvent can lead to a dramatic drag reduction in turbulent flows. This effect has been extensively studied since its discovery in the late 1940's. The drag reduction at first is proportional to the polymer concentration (Weisenberg number) but then saturates to the maximum drag reduction (MDR) asymptote. It is commonly believed that drag reduction results from an adjustment of the turbulent flow structure due to the action of the polymers. We here present experimental results of turbulent pipe flows using dilute polyacrylamid solutions at relatively large Weisenberg numbers (˜10). Our results show that for relatively low polymer concentrations transition to turbulence is postponed to higher Reynolds numbers. However when the Weisenberg number is increased further we find that the subcritical transition to turbulence, typical for Newtonian pipe flow disappears. Instead a supercritical instability is found at much lower Reynolds numbers which gives rise to a disordered flow. The observed drag of this disordered flow is identical to the well known MDR asymptote.

Hof, Björn; Samanta, Devranjan; Wagner, Christian

2011-11-01

166

Clades reach highest morphological disparity early in their evolution.  

PubMed

There are few putative macroevolutionary trends or rules that withstand scrutiny. Here, we test and verify the purported tendency for animal clades to reach their maximum morphological variety relatively early in their evolutionary histories (early high disparity). We present a meta-analysis of 98 metazoan clades radiating throughout the Phanerozoic. The disparity profiles of groups through time are summarized in terms of their center of gravity (CG), with values above and below 0.50 indicating top- and bottom-heaviness, respectively. Clades that terminate at one of the "big five" mass extinction events tend to have truncated trajectories, with a significantly top-heavy CG distribution overall. The remaining 63 clades show the opposite tendency, with a significantly bottom-heavy mean CG (relatively early high disparity). Resampling tests are used to identify groups with a CG significantly above or below 0.50; clades not terminating at a mass extinction are three times more likely to be significantly bottom-heavy than top-heavy. Overall, there is no clear temporal trend in disparity profile shapes from the Cambrian to the Recent, and early high disparity is the predominant pattern throughout the Phanerozoic. Our results do not allow us to distinguish between ecological and developmental explanations for this phenomenon. To the extent that ecology has a role, however, the paucity of bottom-heavy clades radiating in the immediate wake of mass extinctions suggests that early high disparity more probably results from the evolution of key apomorphies at the base of clades rather than from physical drivers or catastrophic ecospace clearing. PMID:23884651

Hughes, Martin; Gerber, Sylvain; Wills, Matthew Albion

2013-08-20

167

Advanced Reach Tool (ART): development of the mechanistic model.  

PubMed

This paper describes the development of the mechanistic model within a collaborative project, referred to as the Advanced REACH Tool (ART) project, to develop a tool to model inhalation exposure for workers sharing similar operational conditions across different industries and locations in Europe. The ART mechanistic model is based on a conceptual framework that adopts a source receptor approach, which describes the transport of a contaminant from the source to the receptor and defines seven independent principal modifying factors: substance emission potential, activity emission potential, localized controls, segregation, personal enclosure, surface contamination, and dispersion. ART currently differentiates between three different exposure types: vapours, mists, and dust (fumes, fibres, and gases are presently excluded). Various sources were used to assign numerical values to the multipliers to each modifying factor. The evidence used to underpin this assessment procedure was based on chemical and physical laws. In addition, empirical data obtained from literature were used. Where this was not possible, expert elicitation was applied for the assessment procedure. Multipliers for all modifying factors were peer reviewed by leading experts from industry, research institutes, and public authorities across the globe. In addition, several workshops with experts were organized to discuss the proposed exposure multipliers. The mechanistic model is a central part of the ART tool and with advancing knowledge on exposure, determinants will require updates and refinements on a continuous basis, such as the effect of worker behaviour on personal exposure, 'best practice' values that describe the maximum achievable effectiveness of control measures, the intrinsic emission potential of various solid objects (e.g. metal, glass, plastics, etc.), and extending the applicability domain to certain types of exposures (e.g. gas, fume, and fibre exposure). PMID:22003239

Fransman, Wouter; Van Tongeren, Martie; Cherrie, John W; Tischer, Martin; Schneider, Thomas; Schinkel, Jody; Kromhout, Hans; Warren, Nick; Goede, Henk; Tielemans, Erik

2011-11-01

168

Development of microgravity, full body functional reach envelope using 3-D computer graphic models and virtual reality technology  

NASA Technical Reports Server (NTRS)

In microgravity conditions mobility is greatly enhanced and body stability is difficult to achieve. Because of these difficulties, optimum placement and accessibility of objects and controls can be critical to required tasks on board shuttle flights or on the proposed space station. Anthropometric measurement of the maximum reach of occupants of a microgravity environment provide knowledge about maximum functional placement for tasking situations. Calculations for a full body, functional reach envelope for microgravity environments are imperative. To this end, three dimensional computer modeled human figures, providing a method of anthropometric measurement, were used to locate the data points that define the full body, functional reach envelope. Virtual reality technology was utilized to enable an occupant of the microgravity environment to experience movement within the reach envelope while immersed in a simulated microgravity environment.

Lindsey, Patricia F.

1994-01-01

169

Maximum Entropy Principle for Transportation  

NASA Astrophysics Data System (ADS)

In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

Bilich, F.; Dasilva, R.

2008-11-01

170

The Sherpa Maximum Likelihood Estimator  

NASA Astrophysics Data System (ADS)

A primary goal for the second release of the Chandra Source Catalog (CSC) is to include X-ray sources with as few as 5 photon counts detected in stacked observations of the same field, while maintaining acceptable detection efficiency and false source rates. Aggressive source detection methods will result in detection of many false positive source candidates. Candidate detections will then be sent to a new tool, the Maximum Likelihood Estimator (MLE), to evaluate the likelihood that a detection is a real source. MLE uses the Sherpa modeling and fitting engine to fit a model of a background and source to multiple overlapping candidate source regions. A background model is calculated by simultaneously fitting the observed photon flux in multiple background regions. This model is used to determine the quality of the fit statistic for a background-only hypothesis in the potential source region. The statistic for a background-plus-source hypothesis is calculated by adding a Gaussian source model convolved with the appropriate Chandra point spread function (PSF) and simultaneously fitting the observed photon flux in each observation in the stack. Since a candidate source may be located anywhere in the field of view of each stacked observation, a different PSF must be used for each observation because of the strong spatial dependence of the Chandra PSF. The likelihood of a valid source being detected is a function of the two statistics (for background alone, and for background-plus-source). The MLE tool is an extensible Python module with potential for use by the general Chandra user.

Nguyen, D.; Doe, S.; Evans, I.; Hain, R.; Primini, F.

2011-07-01

171

Maximum entropy principal for transportation  

SciTech Connect

In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

Bilich, F. [University of Brasilia (Brazil); Da Silva, R. [National Research Council (Brazil)

2008-11-06

172

Recovery of three arctic stream reaches from experimental nutrient enrichment  

USGS Publications Warehouse

1. Nutrient enrichment and resulting eutrophication is a widespread anthropogenic influence on freshwater ecosystems, but recovery from nutrient enrichment is poorly understood, especially in stream environments. We examined multi-year patterns in community recovery from experimental low-concentration nutrient enrichment (N + P or P only) in three reaches of two Arctic tundra streams (Kuparuk River and Oksrukuyik Creek) on the North Slope of Alaska (U.S.A.). 2. Rates of recovery varied among community components and depended on duration of enrichment (2-13 consecutive growing seasons). Biomass of epilithic algae returned to reference levels rapidly (within 2 years), regardless of nutrients added or enrichment duration. Aquatic bryophyte cover, which increased greatly in the Kuparuk River only after long-term enrichment (8 years), took 8 years of recovery to approach reference levels, after storms had scoured most remnant moss in the recovering reach. 3. Multi-year persistence of bryophytes in the Kuparuk River appeared to prevent recovery of insect populations that had either been positively (e.g. the mayfly Ephemerella, most chironomid midge taxa) or negatively (e.g. the tube-building chironomid Orthocladius rivulorum) affected by this shift in dominant primary producer. These lags in recovery (of >3 years) were probably driven by the persistent effect of bryophytes on physical benthic habitat. 4. Summer growth rates of Arctic grayling (both adults and young-of-year) in Oksrukuyik Creek (fertilised for 6 years with no bryophyte colonisation), which were consistently increased by nutrient addition, returned to reference rates within 1-2 years. 5. Rates of recovery of these virtually pristine Arctic stream ecosystems from low-level nutrient enrichment appeared to be controlled largely by duration of enrichment, mediated through physical habitat shifts caused by eventual bryophyte colonisation, and subsequent physical disturbance that removed bryophytes. Nutrient enrichment of oligotrophic Arctic stream ecosystems caused by climate change or local anthropogenic activity may have dramatic and persistent consequences if it results in the colonisation of long-lived primary producers that alter physical habitat. ?? 2007 The Authors.

Benstead, J. P.; Green, A. C.; Deegan, L. A.; Peterson, B. J.; Slavik, K.; Bowden, W. B.; Hershey, A. E.

2007-01-01

173

Hydraulic Limits on Maximum Plant Transpiration  

NASA Astrophysics Data System (ADS)

Photosynthesis occurs at the expense of water losses through transpiration. As a consequence of this basic carbon-water interaction at the leaf level, plant growth and ecosystem carbon exchanges are tightly coupled to transpiration. In this contribution, the hydraulic constraints that limit transpiration rates under well-watered conditions are examined across plant functional types and climates. The potential water flow through plants is proportional to both xylem hydraulic conductivity (which depends on plant carbon economy) and the difference in water potential between the soil and the atmosphere (the driving force that pulls water from the soil). Differently from previous works, we study how this potential flux changes with the amplitude of the driving force (i.e., we focus on xylem properties and not on stomatal regulation). Xylem hydraulic conductivity decreases as the driving force increases due to cavitation of the tissues. As a result of this negative feedback, more negative leaf (and xylem) water potentials would provide a stronger driving force for water transport, while at the same time limiting xylem hydraulic conductivity due to cavitation. Here, the leaf water potential value that allows an optimum balance between driving force and xylem conductivity is quantified, thus defining the maximum transpiration rate that can be sustained by the soil-to-leaf hydraulic system. To apply the proposed framework at the global scale, a novel database of xylem conductivity and cavitation vulnerability across plant types and biomes is developed. Conductivity and water potential at 50% cavitation are shown to be complementary (in particular between angiosperms and conifers), suggesting a tradeoff between transport efficiency and hydraulic safety. Plants from warmer and drier biomes tend to achieve larger maximum transpiration than plants growing in environments with lower atmospheric water demand. The predicted maximum transpiration and the corresponding leaf water potential compare well with measured peak transpiration and minimum water potentials across plant types and biomes, suggesting that plant water transport system and stomatal regulation co-evolved to meet peak atmospheric demands, thus sustaining carbon uptake while avoiding tissue damage even in such harsh conditions.

Manzoni, S.; Vico, G.; Katul, G. G.; Palmroth, S.; Jackson, R. B.; Porporato, A. M.

2011-12-01

174

Maximum vehicle cabin temperatures under different meteorological conditions.  

PubMed

A variety of studies have documented the dangerously high temperatures that may occur within the passenger compartment (cabin) of cars under clear sky conditions, even at relatively low ambient air temperatures. Our study, however, is the first to examine cabin temperatures under variable weather conditions. It uses a unique maximum vehicle cabin temperature dataset in conjunction with directly comparable ambient air temperature, solar radiation, and cloud cover data collected from April through August 2007 in Athens, GA. Maximum cabin temperatures, ranging from 41-76 degrees C, varied considerably depending on the weather conditions and the time of year. Clear days had the highest cabin temperatures, with average values of 68 degrees C in the summer and 61 degrees C in the spring. Cloudy days in both the spring and summer were on average approximately 10 degrees C cooler. Our findings indicate that even on cloudy days with lower ambient air temperatures, vehicle cabin temperatures may reach deadly levels. Additionally, two predictive models of maximum daily vehicle cabin temperatures were developed using commonly available meteorological data. One model uses maximum ambient air temperature and average daily solar radiation while the other uses cloud cover percentage as a surrogate for solar radiation. From these models, two maximum vehicle cabin temperature indices were developed to assess the level of danger. The models and indices may be useful for forecasting hazardous conditions, promoting public awareness, and to estimate past cabin temperatures for use in forensic analyses. PMID:19234721

Grundstein, Andrew; Meentemeyer, Vernon; Dowd, John

2009-05-01

175

Maximum Parsimony on Phylogenetic networks  

PubMed Central

Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are common to all the branching patterns introduced by the reticulate vertices. Thus the score contains an in-built cost for the number of reticulate vertices in the network, and would provide a criterion that is comparable among all networks. Although the problem of finding the parsimony score on the network is believed to be computationally hard to solve, heuristics such as the ones described here would be beneficial in our efforts to find a most parsimonious network.

2012-01-01

176

Maximum Flux Transition Paths of Conformational Change.  

PubMed

Given two metastable states A and B of a biomolecular system, the problem is to calculate the likely paths of the transition from A to B. Such a calculation is more informative and more manageable if done for a reduced set of collective variables chosen so that paths cluster in collective variable space. The computational task becomes that of computing the "center" of such a cluster. A good way to define the center employs the concept of a committor, whose value at a point in collective variable space is the probability that a trajectory at that point will reach B before A. The committor "foliates" the transition region into a set of isocommittors. The maximum flux transition path is defined as a path that crosses each isocommittor at a point which (locally) has the highest crossing rate of distinct reactive trajectories. This path is based on the same principle as the minimum resistance path of Berkowitz et al (1983), but it has two advantages: (i) the path is invariant with respect to a change of coordinates in collective variable space and (ii) the differential equations that define the path are simpler. It is argued that such a path is nearer to an ideal path than others that have been proposed with the possible exception of the finite-temperature string method path. To make the calculation tractable, three approximations are introduced, yielding a path that is the solution of a nonsingular two-point boundary-value problem. For such a problem, one can construct a simple and robust algorithm. One such algorithm and its performance is discussed. PMID:20890401

Zhao, Ruijun; Shen, Juanfang; Skeel, Robert D

2010-08-10

177

Three-dimensional reaching tasks: effect of reaching height and width on upper limb kinematics and muscle activity.  

PubMed

In previous studies, upper limb coordination was usually analyzed during two-dimensional (2D) arm movements. Based on joint kinematics and muscle activity, it has been demonstrated that the shoulder joint controls the multi-joint movement. This study focused on three-dimensional (3D) reaching tasks and examined if the coordination strategies previously described in 2D can be transferred to 3D movements and if reaching to different locations in space has an effect on kinematic and upper limb muscle strategies. Ten healthy subjects reached to nine different targets in 3D space placed at arm length. Kinematic data of the shoulder and elbow and electrical activity of 10 upper limb muscles were registered. Differences in kinematics and EMG were compared between different reaching conditions. Activity of shoulder muscles increased earlier than elbow muscles inducing shoulder elevation prior to elbow extension. Reaching at different widths only influenced shoulder kinematics, whereas reaching at different heights influenced both shoulder and elbow joints. Modulation of reaching height induced an immediate adaptation of elbow flexion followed by an adaptation of shoulder elevation. As previously described in 2D, the shoulder joint leads the movement during 3D reaching tasks. Changing the 3D nature of a reaching task influenced the interaction between shoulder and elbow joint, with reaching height primarily affecting the elbow coordination strategy. PMID:20729085

Vandenberghe, Annelies; Levin, Oron; De Schutter, Joris; Swinnen, Stephan; Jonkers, Ilse

2010-10-01

178

Multiple Parietal Reach Regions in Humans: Cortical Representations for Visual and Proprioceptive Feedback during On-Line Reaching  

PubMed Central

Reaching toward a visual target involves at least two sources of information. One is the visual feedback from the hand as it approaches the target. Another is proprioception from the moving limb, which informs the brain of the location of the hand relative to the target even when the hand is not visible. Where these two sources of information are represented in the human brain is unknown. In the present study, we investigated the cortical representations for reaching with or without visual feedback from the moving hand, using functional magnetic resonance imaging. To identify reach-dominant areas, we compared reaching with saccades. Our results show that a reach-dominant region in the anterior precuneus (aPCu), extending into medial intraparietal sulcus, is equally active in visual and nonvisual reaching. A second region, at the superior end of the parieto-occipital sulcus (sPOS), is more active for visual than for nonvisual reaching. These results suggest that aPCu is a sensorimotor area whose sensory input is primarily proprioceptive, while sPOS is a visuomotor area that receives visual feedback during reaching. In addition to the precuneus, medial, anterior intraparietal, and superior parietal cortex were also activated during both visual and nonvisual reaching, with more anterior areas responding to hand movements only and more posterior areas responding to both hand and eye movements. Our results suggest that cortical networks for reaching are differentially activated depending on the sensory conditions during reaching. This indicates the involvement of multiple parietal reach regions in humans, rather than a single homogenous parietal reach region.

Filimon, Flavia; Nelson, Jonathan D.; Huang, Ruey-Song; Sereno, Martin I.

2012-01-01

179

Tracked Vehicle Acceleration: Maximum and Minimum Speeds.  

National Technical Information Service (NTIS)

This document describes procedures for conducting acceleration and maximum and minimum speed tests of tracked vehicles. Acceleration and maximum speed are basic measures of vehicle power; they define the ability of a vehicle to execute a change in locatio...

1987-01-01

180

Temporal and spatial evolution of the Antarctic sea ice prior to the September 2012 record maximum extent  

NASA Astrophysics Data System (ADS)

24 September 2012 the Antarctic sea ice extent (SIE) reached a new annual daily maximum (ADM) for the satellite era of 19.72 × 106 km2. The largest positive SIE anomalies compared to the mean of all ADMs were found over the northern Amundsen Sea, off the coast of Wilkes Land, with smaller positive anomalies off the Dronning Maud Land coast (30°W to 30°E). The SIE at the ADM is significantly correlated with the extents for the previous 80 days, but the ice growth during the winter of 2012 was close to the climatological rate, and 1 month before the ADM, the SIE was near the recent mean. Deep depressions in the circumpolar trough since late August 2012 resulted in strong southerly flow and marked northward sea ice advection. The linear trend in SIE suggests that it contributed ~40% to the 2012 anomaly, with depression activity adding ~60%.

Turner, John; Hosking, J. Scott; Phillips, Tony; Marshall, Gareth J.

2013-11-01

181

The Relaxed Online Maximum Margin Algorithm  

Microsoft Academic Search

We describe a new incremental algorithm for training linear threshold functions: the Relaxed Online Maximum Margin Algorithm, or ROMMA. ROMMA can be viewed as an approximation to the algorithm that repeatedly chooses the hyperplane that classifies previously seen examples correctly with the maximum margin. It is known that such a maximum-margin hypothesis can be computed by minimizing the length of

Yi Li; Philip M. Long

2002-01-01

182

Validating CAR - A comparison study of experimentally-derived and computer-generated reach envelopes. [Crewstation Assessment of Reach  

NASA Technical Reports Server (NTRS)

In the present investigation, Crewstation Assessment of Reach (CAR) results in the form of male hand reach envelopes were generated and compared with an anthropometric survey performed by Kennedy (1978) to determine the extent of the validity of the CAR model with respect to experimentally-derived anthropometric data. The CAR-generated reach envelopes extensively matched the Kennedy envelopes. The match was particularly good in the areas to the front and side from which the reach originated. Attention is given to the crewstation model, the operator sample population, the CAR analysis, aspects of validation methodology, and the modeling of experimental parameters.

Harris, R.; Bennett, J.; Stokes, J.

1982-01-01

183

Considering Reach in Tangible and Table Top Design  

Microsoft Academic Search

Reach heavily impacts all aspects of designing for tangible and tabletop user interfaces. It dictates the input space available to each user and heavily shapes how that space is used. Despite its impact to date tangible, table top, and user interface design have all largely overlooked reach as a design constraint. As a result advancing the state of the art

Aaron Toney; Bruce H. Thomas

2006-01-01

184

The coordination of reaching and grasping in spastic hemiparesis  

Microsoft Academic Search

The kinematics and intrinsic dynamics of reaching and grasping movements in six subjects with spastic hemiparesis were studied. Movements were performed with both hands together as well as with each hand in isolation, and two target widths were used. As expected, large manual asymmetries existed in unimanual task performance. These asymmetries were more pronounced for grasping than for reaching, which

Bert Steenbergen; Edwin van Thiel; Wouter Hulstijn; Ruud G. J. Meulenbroek

2000-01-01

185

Postural responses to unexpected perturbations of balance during reaching  

PubMed Central

To study the interaction between feedforward and feedback modes of postural control, we investigated postural responses during unexpected perturbations of the support surface that occurred during forward reaching in a standing position. We examined postural responses in lower limb muscles of 9 human subjects. Baseline measures were obtained when subjects executed reaching movements to a target placed in front of them (R condition) and during postural responses to forward and backward support-surface perturbations (no reaching, P condition) during quiet stance. Perturbations were also given at different delays after the onset of reaching movements (RP conditions) as well as with the arm extended in the direction of the target, but not reaching (P/AE condition). Results showed that during perturbations to reaching (RP), the initial automatic postural response, occurring around 100 ms after the onset of perturbations, was relatively unchanged in latency or amplitude compared to control conditions (P and P/AE). However, longer latency postural responses were modulated to aid in the reaching movements during forward perturbations but not during backward perturbations. Our results suggest that the nervous system prioritizes the maintenance of a stable postural base during reaching, and that later components of the postural responses can be modulated to ensure the performance of the voluntary task.

Trivedi, Hari; Leonard, Julia A.; Ting, Lena H.; Stapley, Paul J.

2014-01-01

186

Maximum allowable heat flux for a submerged horizontal tube bundle  

SciTech Connect

For application to industrial heating of large pools by immersed heat exchangers, the socalled maximum allowable (or {open_quotes}critical{close_quotes}) heat flux is studied for unconfined tube bundles aligned horizontally in a pool without forced flow. In general, we are considering boiling after the pool reaches its saturation temperature rather than sub-cooled pool boiling which should occur during early stages of transient operation. A combination of literature review and simple approximate analysis has been used. To date our main conclusion is that estimates of q inch chf are highly uncertain for this configuration.

McEligot, D.M.

1995-08-14

187

Effects of cultivating conditions on the mycelial growth of Ganoderma lucidum in submerged flask cultures  

Microsoft Academic Search

In this paper the effects of environmental conditions on the mycelial growth of Ganoderma lucidum were investigated in shake flask cultures. The optimal temperature and pH were found to be around 30-35v°C and 4, respectively, in a glucose-ammonium chloride medium. The maximum mycelial concentration reached to around 350 mg\\/100 ml. The formation of mycelial pellets and their ultra structure was

F.-C. Yang; C.-B. Liau

1998-01-01

188

Growth of bean in high CO2: Effects on shoot mineral composition  

Microsoft Academic Search

It is widely recognized that a high CO2 concentration in the atmosphere can alter plant growth, but the effects of high CO2 on other plant characteristics are unclear. Bean plants (Phaseolus vulgaris L.) grown in 1200 ?1 1 CO2 reached a maximum vegetative shoot dry weight more rapidly than ambient?CO2?grown (350 ?1 1?) plants. While shoot dry weights of high

Michael A. Porter; Bernard Grodzinski

1989-01-01

189

Differences in the Heritability of Growth and Growth Velocity During Infancy and Associations With FTO Variants  

PubMed Central

While the associations of common variants in the FTO gene with obesity have been widely replicated in adults, there is conflicting evidence regarding their effects in infancy. We hypothesize that the genetic influences on growth traits vary during infancy, and that conflicting results may stem from variation in the ages at which FTO associations have been examined. Using longitudinal weight and length data at 0, 1, 3, 6, 9, 12, 18, 24, 30, and 36 months in 917 (444 females, 473 males) family members from the Fels Longitudinal Study, we used a variance components–based approach (SOLAR) to: (i) examine differences in heritability (gene-by-age interaction) in weight, length, relative weight (BMI and ponderal index (PI)) and instantaneous weight and length velocities over the course of infancy, and (ii) test whether a common FTO variant (rs9939609) was associated with infant growth at three ages (maximum trait heritability, birth and 36 months). All heritabilities at birth (of 39–74%) were significant (P < 3.9 × 10?10), but changed with age (gene-by-age interaction, P < 0.05). Weight, relative weight, and weight velocity reached maximum heritabilities (of 76–89%) at 6–9 months, while length and length velocity reached maximum heritabilities (of 96–99%) at 18–30 months. We found no association of rs9939609 with growth status or velocity measured at any age (P > 0.11). This study for the first time demonstrates the fluctuation of genetic influences on infant growth, but further work is required to determine which gene variants explain the strong additive genetic effects observed.

Choh, Audrey C.; Curran, Joanne E.; Odegaard, Andrew O.; Nahhas, Ramzi W.; Czerwinski, Stefan A.; Blangero, John; Towne, Bradford; Demerath, Ellen W.

2014-01-01

190

LHC reach for gauge mediated supersymmetry breaking models via prompt photon channels  

NASA Astrophysics Data System (ADS)

We evaluate the supersymmetry reach of the Large Hadron Collider within the gauge-mediated low energy supersymmetry breaking framework, assuming that a neutralino is the second lightest sparticle and that it decays promptly into a gravitino which escapes detection. We find that the maximum reach is obtained via a search for inclusive ??+ET events coming dominantly from chargino and neutralino production. Assuming an integrated luminosity of 10 fb-1, we find that LHC experiments will be able to probe values of the model parameter ?<~400 TeV, corresponding to mg~<=2.8 TeV. A measure of the model parameter ? may be possible from the photon pT spectrum.

Baer, Howard; Mercadante, Pedro G.; Paige, Frank; Tata, Xerxes; Wang, Yili

1998-09-01

191

Population growth and economic growth.  

PubMed

This discussion of the issues relating to the problem posed by population explosion in the developing countries and economic growth in the contemporary world covers the following: predictions of economic and social trends; the Malthusian theory of population; the classical or stationary theory of population; the medical triage model; ecological disaster; the Global 2000 study; the limits to growth; critiques of the Limits to Growth model; nonrenewable resources; food and agriculture; population explosion and stabilization; space and ocean colonization; and the limits perspective. The Limits to Growth model, a general equilibrium anti-growth model, is the gloomiest economic model ever constructed. None of the doomsday models, the Malthusian theory, the classical stationary state, the neo-Malthusian medical triage model, the Global 2000 study, are so far reaching in their consequences. The course of events that followed the publication of the "Limits to Growth" in 1972 in the form of 2 oil shocks, food shock, pollution shock, and price shock seemed to bear out formally the gloomy predictions of the thesis with a remarkable speed. The 12 years of economic experience and the knowledge of resource trends postulate that even if the economic pressures visualized by the model are at work they are neither far reaching nor so drastic. Appropriate action can solve them. There are several limitations to the Limits to Growth model. The central theme of the model, which is overshoot and collapse, is unlikely to be the course of events. The model is too aggregative to be realistic. It exaggerates the ecological disaster arising out of the exponential growth of population and industry. The gross underestimation of renewable resources is a basic flaw of the model. The most critical weakness of the model is its gross underestimation of the historical trend of technological progress and the technological possiblities within industry and agriculture. The model does correctly emphasize the exponential growth of population as the source of several complications for economic growth and human welfare. Stabilization of population by reducing fertility is conducive for improving the quality of population and also advances the longterm management of the population growth and work force utilization. The perspective of longterm economic management involves populatio n planning, control of environmental pollution, conservation of scarce resources, exploration of resources, realization of technological possibilities in agriculture and industry and in farm and factory, and achievement of economic growth and its equitable distribution. PMID:12314595

Narayana, D L

1984-01-01

192

Project Career REACH: Marketing Strategies for Effective Guidance Programs.  

ERIC Educational Resources Information Center

Outlines the practical marketing strategies used to implement Project Career REACH, a career development program for high school freshmen. Marketing basics for guidance programs are discussed, including mission analysis, market analysis, resource analysis, strategic planning, and evaluation. (TE)

Bollendorf, Marsha; And Others

1990-01-01

193

High-Reach Extendable Turrets with Skin-Penetrating Nozzle.  

National Technical Information Service (NTIS)

New equipment for aircraft rescue firefighting vehicles can help improve firefighting after an aircraft crash. New equipment such as a high-reach extendable turret (HRET) with skin-penetrating nozzle mounted on an airport firefighting vehicle could exting...

K. Bagot N. Subbotin

2005-01-01

194

Reaching Our Children: A Compendium of Outreach Models.  

National Technical Information Service (NTIS)

Millions of children face multiple barriers in accessing health care services. There are presently over 10 million uninsured children in America, and over four million of those children are eligible for Medicaid but not enrolled. Reaching out to these chi...

2006-01-01

195

Helping the Library Reach Out to the Future  

MedlinePLUS

... Bar Home Current Issue Past Issues Helping the Library Reach Out to the Future Past Issues / Fall ... On behalf of the Friends of the National Library of Medicine (FNLM), welcome to the Fall 2007 ...

196

Do transient storage parameters directly scale in longer, combined stream reaches? Reach length dependence of transient storage interpretations  

NASA Astrophysics Data System (ADS)

SummaryLittle work has been done to assess parameterizations and related interpretations (i.e., metrics of exchange) of transient storage modeling (TSM) over multiple spatial scales in streams. In this paper, we simulate conservative solute transport in a small mountain stream over combinations of five consecutive sub-reaches (38 m, 105 m, 281 m, 433 m, and 619 m below injection point) to (1) determine how optimized parameter estimates vary with reach length and reach combination, and (2) evaluate whether equally well-optimized simulations of solute transport in the channel result in varying interpretations of tracer exchange with the storage zone. Each simulated stream solute concentration breakthrough curve (BTC) showed consistently accurate fits to observations. However, our results indicate approximate equifinality (similar fits from different parameter sets) in the simulations of concentrations of stream tracer across individual sub-reaches and combined reaches leading to varying interpretations of transient storage exchange parameterization (i.e., variable optimized parameter estimates) and concentration time series of tracer in the storage zone. These results suggest strong reach-length dependence in simulated exchange. Based on stream BTCs alone, the TSM is useful in characterizing the influence of transient storage on in-stream solute transport, though it does not consistently reproduce storage zone dynamics. Characterization of the solute exchange between the stream and the storage zones remains problematic, and the effects of transient storage cannot be directly compared within overlapping stream reaches, an important consideration in designing and interpreting stream solute transport experiments.

Gooseff, Michael N.; Briggs, Martin A.; Bencala, Kenneth E.; McGlynn, Brian L.; Scott, Durelle T.

2013-03-01

197

A neural mechanism of synergy formation for whole body reaching  

Microsoft Academic Search

The present study proposes a computational model for the formation of whole body reaching synergy, i.e., coordinated movements\\u000a of lower and upper limbs, characterized by a focal component (the hand must reach a target) and a postural component (the\\u000a center of mass must remain inside the support base). The model is based on an extension of the equilibrium point hypothesis

Pietro Morasso; Maura Casadio; Vishwanathan Mohan; Jacopo Zenzeri

2010-01-01

198

Time-invariant reference frames for parietal reach activity.  

PubMed

Neurophysiological studies suggest that the transformation of visual signals into arm movement commands does not involve a sequential recruitment of the various reach-related regions of the cerebral cortex but a largely simultaneous activation of these areas, which form a distributed and recurrent visuomotor network. However, little is known about how the reference frames used to encode reach-related variables in a given "node" of this network vary with the time taken to generate a behavioral response. Here we show that in an instructed delay reaching task, the reference frames used to encode target location in the parietal reach region (PRR) and area 5 of the posterior parietal cortex (PPC) do not evolve dynamically in time; rather the same spatial representation exists within each area from the time target-related information is first instantiated in the network until the moment of movement execution. As previously reported, target location was encoded predominantly in eye coordinates in PRR and in both eye and hand coordinates in area 5. Thus, the different computational stages of the visuomotor transformation for reaching appear to coexist simultaneously in the parietal cortex, which may facilitate the rapid adjustment of trajectories that are a hallmark of skilled reaching behavior. PMID:18368398

Buneo, Christopher A; Batista, Aaron P; Jarvis, Murray R; Andersen, Richard A

2008-06-01

199

ReachOut opens women's center in Angeles.  

PubMed

In the Philippines, ReachOut AIDS Education Foundation opened a reproductive health center for female sex workers in Angeles City; the Australian Agency for International Development (AUSAID) provided funds. The women will be counseled about prevention of human immunodeficiency virus (HIV), acquired immunodeficiency syndrome (AIDS), and sexually transmitted diseases (STDs); genital health; and family planning. Establishment-based and freelance sex workers will be trained to provide outreach education to fellow workers. Condoms and educational materials will be distributed along with affordable meals. Legal aid, alternative livelihood projects, and rehabilitation will be provided. ReachOut actively coordinates with the Angeles City Health Department, the Task Force on AIDS, and the League of Angeles City Entertainers and Managers. ReachOut has a similar program, funded by the United Nations Population Fund (UNFPA), in the City of Makati. Another will be established in Baguio City, and a mobile STD clinic will be assigned to the Manila port areas frequented by stevedores, port handlers, seafarers, and truck drivers. ReachOut also runs education projects, targeting various population groups, in beerhouses, and operates the AIDS Helpline, a telephone counseling service for the general public. An AIDS Mobile Van provides counseling to female sex workers in Pasay. ReachOut also provides free HIV antibody tests, STD diagnosis and treatment, family planning counseling and service, training, and seminars. ReachOut projects are funded by UNFPA, AUSAID, the US Agency for International Development (USAID), and the Japanese government. PMID:12347463

1995-01-01

200

Maximum Urban Heat Island Intensity in Seoul.  

NASA Astrophysics Data System (ADS)

The maximum urban heat island (UHI) intensity in Seoul, Korea, is investigated using data measured at two meteorological observatories (an urban site and a rural site) during the period of 1973-96. The average maximum UHI is weakest in summer and is strong in autumn and winter. Similar to previous studies for other cities, the maximum UHI intensity is more frequently observed in the nighttime than in the daytime, decreases with increasing wind speed, and is pronounced for clear skies. A multiple linear regression analysis is performed to relate the maximum UHI to meteorological elements. Four predictors considered in this study are the maximum UHI intensity for the previous day, wind speed, cloudiness, and relative humidity. The previous-day maximum UHI intensity is positively correlated with the maximum UHI, and the wind speed, cloudiness, and relative humidity are negatively correlated with the maximum UHI intensity. Among the four predictors, the previous-day maximum UHI intensity is the most important. The relative importance among the predictors varies depending on time of day and season. A three-layer back-propagation neural network model with the four predictors as input units is constructed to predict the maximum UHI intensity in Seoul, and its performance is compared with that of a multiple linear regression model. For all test datasets, the neural network model improves upon the regression model in predicting the maximum UHI intensity. The improvement of the neural network model upon the regression model is 6.3% for the unstratified test data, is higher in the daytime (6.1%) than in the nighttime (3.3%), and ranges from 0.8% in spring to 6.5% in winter.

Kim, Yeon-Hee; Baik, Jong-Jin

2002-06-01

201

Reliability in the Parameterization of the Functional Reach Test in Elderly Stroke Patients: A Pilot Study  

PubMed Central

Background. Postural instability is one of the major complications found in stroke survivors. Parameterising the functional reach test (FRT) could be useful in clinical practice and basic research. Objectives. To analyse the reliability, sensitivity, and specificity in the FRT parameterisation using inertial sensors for recording kinematic variables in patients who have suffered a stroke. Design. Cross-sectional study. While performing FRT, two inertial sensors were placed on the patient's back (lumbar and trunk). Participants. Five subjects over 65 who suffer from a stroke. Measurements. FRT measures, lumbosacral/thoracic maximum angular displacement, maximum time of lumbosacral/thoracic angular displacement, time return initial position, and total time. Speed and acceleration of the movements were calculated indirectly. Results. FRT measure is??12.75 ± 2.06?cm. Intrasubject reliability values range from 0.829 (time to return initial position (lumbar sensor)) to 0.891 (lumbosacral maximum angular displacement). Intersubject reliability values range from 0.821 (time to return initial position (lumbar sensor)) to 0.883 (lumbosacral maximum angular displacement). FRT's reliability was 0.987 (0.983–0.992) and 0.983 (0.979–0.989) intersubject and intrasubject, respectively. Conclusion. The main conclusion could be that the inertial sensors are a tool with excellent reliability and validity in the parameterization of the FRT in people who have had a stroke.

Merchan-Baeza, Jose Antonio; Gonzalez-Sanchez, Manuel; Cuesta-Vargas, Antonio Ignacio

2014-01-01

202

The Holocene Thermal Maximum in the Greenland Sea and Fram Strait: Temporal and spatial variability  

NASA Astrophysics Data System (ADS)

The Holocene Thermal Maximum (HTM) is a distinct time interval in the early Holocene when strong advection of Atlantic Water to the northern Nordic Seas led to the development of conditions favorable for plankton growth due to limited sea ice coverage. Here we present a synthesis of records from the northern and western part of this area, reaching from the SW Greenland Sea (73°N) to the Yermak Plateau (81°N) and revealing temporal and spatial differences in HTM development. High-resolution radiocarbon dating enables us to constrain the timing of the HTM on (sub)millennial scale resolution. In the Fram Strait and on the Yermak Plateau, rapidly increasing subpolar foraminiferal amounts in the sediments and calculated fluxes indicate the arrival of subsurface warm and saline Atlantic Water at 11-10.5 ka. Depending on the temporal resolution, the records show that the maximum influx was terminated already 2000 years later (9-8 ka), contemporaneous to the short period of maximum sea surface temperatures (cf. Risebrobakken et al., 2011, Paleoceanography v. 26). In the northernmost Greenland Sea, low-resolution records show that the timing may have been similar here. A new submilliennial-scale record from the Vesterisbanken (73°N) in the Greenland Sea, however, reveals a somewhat different picture for this more southern area, affected by the Greenland Gyre. A reduction in annual ice coverage, as indicated by increasing total amounts of planktic foraminifers in the sediment, also occurred between 11 and 10 ka, but the maximum Atlantic Water advection came later (9 ka) and lasted until 6 ka. Apparently, the SW Greenland Sea site records the history of Atlantic Water in the Greenland Gyre that decoupled from the northward flowing Norwegian Atlantic Current/Westspitsbergen Current south of the Fram Strait and supplied relatively high amounts of heat to the subsurface Greenland Sea well into the middle Holocene. At that time, the more northerly sites had already experienced a substantial cooling and an increase in ice coverage, probably induced by a stronger sea ice production in the Arctic Ocean than in the Early Holocene.

Spielhagen, Robert F.; Bauch, Henning A.; Not, Christelle; Telesinski, Maciej M.; Werner, Kirstin

2014-05-01

203

'Reaching the hard to reach' - lessons learned from the VCS (voluntary and community Sector). A qualitative study  

PubMed Central

Background The notion 'hard to reach' is a contested and ambiguous term that is commonly used within the spheres of social care and health, especially in discourse around health and social inequalities. There is a need to address health inequalities and to engage in services the marginalized and socially excluded sectors of society. Methods This paper describes a pilot study involving interviews with representatives from eight Voluntary and Community Sector (VCS) organisations. The purpose of the study was to explore the notion of 'hard to reach' and perceptions of the barriers and facilitators to accessing services for 'hard to reach' groups from a voluntary and community sector perspective. Results The 'hard to reach' may include drug users, people living with HIV, people from sexual minority communities, asylum seekers, refugees, people from black and ethnic minority communities, and homeless people although defining the notion of the 'hard to reach' is not straight forward. It may be that certain groups resist engaging in treatment services and are deemed hard to reach by a particular service or from a societal stance. There are a number of potential barriers for people who may try and access services, including people having bad experiences in the past; location and opening times of services and how services are funded and managed. A number of areas of commonality are found in terms of how access to services for 'hard to reach' individuals and groups could be improved including: respectful treatment of service users, establishing trust with service users, offering service flexibility, partnership working with other organisations and harnessing service user involvement. Conclusions If health services are to engage with groups that are deemed 'hard to reach' and marginalised from mainstream health services, the experiences and practices for engagement from within the VCS may serve as useful lessons for service improvement for statutory health services.

2010-01-01

204

On the maximum mass of neutron stars  

Microsoft Academic Search

Upper limits to the maximum mass of neutron stars with locally isotropic pressure are derived within the framework of general relativity and discussed. The equations of stellar structure for stars with locally anisotropic pressure are derived from the field equations of general relativity, and upper limits to the maximum mass for such stars as derived and discussed. The equations of

D. R. Mikkelsen

1975-01-01

205

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2013 CFR

...the maximum civil penalty is $175,000 if the violation results in death, serious illness...no minimum civil penalty, except for a minimum...the maximum civil penalty is $175,000 if the violation results in death, serious...

2013-10-01

206

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2010 CFR

...the maximum civil penalty is $100,000 if the violation results in death, serious illness...minimum $450 civil penalty applies to a violation...the maximum civil penalty is $100,000 if the violation results in death, serious...

2009-10-01

207

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2010 CFR

...the maximum civil penalty is $110,000 if the violation results in death, serious illness...minimum $495 civil penalty applies to a violation...the maximum civil penalty is $110,000 if the violation results in death, serious...

2010-10-01

208

Radiochemical spectral analysis by maximum likelihood  

Microsoft Academic Search

The radiochemical spectral analysis problem is expressed mathematically. ; Maximum likelihood estimates are derived for the two situations of standard ; spectra well-known and standard spectra imprecise. The maximum likelihood method ; is applied to backward-scattered alpha particle analysis of lunar soil samples ; from the Surveyor V moonlander. The standard spectra are assumed known. (JSR)

W. L. Nicholson; D. L. Jr. Stevens

1975-01-01

209

Maximum Likelihood Estimation in Generalized Rasch Models  

Microsoft Academic Search

We review various models and techniques that have been proposed for item analysis according to the ideas of Rasch. A general model is proposed that unifies them, and maximum likelihood procedures are discussed for this general model. We show that unconditional maximum likelihood estimation in the functional Rasch model, as proposed by Wright and Haberman, is an important special case.

Jan De Leeuw; Norman Verhelst

1986-01-01

210

Maximum Entropy Pole-Zero Estimation.  

National Technical Information Service (NTIS)

Maximum Entropy has been suggested by numerous authors as a good objective measure for optimally modeling the power spectrum of a wide-sense stationary random process. This documents describes a new Maximum Entropy pole-zero spectrum estimation method. Th...

B. R. Musicus A. M. Kabel

1985-01-01

211

Magnetic field generated resistivity maximum in graphite  

NASA Technical Reports Server (NTRS)

In zero magnetic field, B, the electrical resistivity, rho(O,T) of highly oriented pyrolytic (polycrystalline) graphite drops smoothly with decreasing T, becoming constant below 4 K. However, in a fixed applied magnetic field B, the resistivity rho(B,T) goes through a maximum as a function of T, with larger maximum for larger B. The temperature of the maximum increases with B, but saturates to a constant value near 25 K (exact T depends on sample) at high B. In single crystal graphite a maximum in rho(B,T) as a function of T is also present, but has the effects of Landau level quantization superimposed. Several possible explanations for the rho(B,T) maximum are proposed, but a complete explanation awaits detailed calculations involving the energy band structure of graphite, and the particular scattering mechanisms involved.

Wollam, J. A.; Kreps, L. W.; Rojeski, M.; Vold, T.; Devaty, R.

1976-01-01

212

Maximum oxygen uptake utilising different treadmill protocols.  

PubMed Central

The study compared five treadmill protocols (four utilising a motorised, and one a non-motorised, treadmill) on maximum oxygen uptake. The five male and five female subjects, all actively engaged in training, were assigned the tests in random order. Statistical analysis revealed no significant differences between the five protocols for maximal oxygen uptake, maximum ventilation, maximum heart rate and blood lactate inflection point, relative to maximal oxygen uptake. Significant differences were observed between the 3' protocol with incline increments of 1.5% and all other protocols on time to exhaustion (p = less than 0.01) and maximum blood lactate levels (HLA, p = less than 0.05). The results indicate that the protocols used in this study did not significantly influence the maximum oxygen uptake attained. Images p74-a p74-b p74-c

Davies, B.; Daggett, A.; Jakeman, P.; Mulhall, J.

1984-01-01

213

Hydraulic characterization of the middle reach of the Congo River  

NASA Astrophysics Data System (ADS)

Little is known about the hydraulics of the Congo River compared to other large rivers, such as the Amazon, Nile and Mississippi, despite it draining an area greater than 3.7 million square kilometers and being the seconded largest river in terms of discharge. While there has been some study of the Congo Basin, most of these concentrate on ecology or the human aspects, but few look at the either the hydrology or hydraulic characteristics of the river. Of the published hydrology/hydraulic research, most concentrates on the hydrology of the Congo Basin aiming to alleviate some of the issues relating to a sparse river gauging network that currently exists. Even fewer studies have looked at hydraulics of the Congo, and usually over a relatively small area of the basin. To undertake a larger study area requires more details on the characteristics of the Congo River. The Congo River can be divided into three distinct reaches; the upper, middle and lower reaches. We concentrate on the middle reach which starts upstream at Boyoma falls, just south of Kisangani, and ends downstream at Livingstone Falls, at Kinshasa (DRC), Brazzaville (Congo) and the Pool Malebo. From Kisangani to Kinshasa, the middle Congo crosses the equator twice and is join by two large tributaries (Ubangi, Kasai) and is highly braided. The middle reach of the Congo is especially important as its still largely undisturbed wetlands are the seconded largest tropical wetlands globally. It is also the main transportation link between Kisangani and Kinshasa, the two largest cities in the DRC. By utilizing remotely sensed Landsat and Icesat datasets, we present the first detailed study on the hydraulic characterization of the middle reach of the Congo River. With these datasets we identify the main control points of flow in the middle reach, investigate how the water surface slope, channel width, islands and braids vary between high and low flows and spatially along the reach. We compare the middle reach of the Congo to other large braided rivers to highlight how the Congo is unique. This detailed analysis will yield key hydraulic characteristics for large reaches of the main channel and tributaries that will be essential for correct hydraulic modeling of the river in due course, and will also provide new insights into the behavior and hydrodynamics of this mysterious river.

O'Loughlin, F.; Trigg, M.; Schumann, G.; Bates, P. D.

2012-12-01

214

Saturated muscle activation contributes to compensatory reaching strategies following stroke  

PubMed Central

The control and execution of movement could potentially be altered by the presence of stroke-induced weakness if muscles are incapable of generating sufficient power. The purpose of this study was to identify compensatory strategies during a forward (sagittal) reaching task for twenty persons with chronic stroke and ten healthy age-matched controls. We hypothesized that the paretic anterior deltoid would be maximally activated (i.e., saturated) during a reaching task and that task completion would require activation of additional muscles, resulting in compensatory movements out of the sagittal plane. For reaching movements by control subjects, joint motion remained largely in the sagittal plane and hand trajectories were smooth and direct. Movement characteristics of the non-paretic arm of stroke subjects were similar to control subjects except for small increases in the abduction angle and the percentage that anterior deltoid was activated. In contrast, reaching movements of the paretic arm of stroke subjects were characterized by increased activation of all muscles, especially the lateral deltoid, in addition to the anterior deltoid, with resulting shoulder abduction power and segmented and indirect hand motion. For the paretic arm of stroke subjects, muscle and kinetic compensations increased with impairment severity and weaker muscles were used at a higher percentage of their available muscle activity. These results suggest that the inability to generate sufficient force with the typical agonists involved during a forward reaching task may necessitate compensatory muscle recruitment strategies to complete the task.

McCrea, Patrick H; Eng, Janice J; Hodgson, Antony J

2012-01-01

215

Retrieving groundwater depth in the lower reaches of Tarim River by NDVI  

NASA Astrophysics Data System (ADS)

The changes of the coverage of vegetation and groundwater depth during the period of ecological construction and environmental protection are the most important two indicators of the level of success in ecological water transportation project in lower reaches of Tarim River.In this study, a new way to predict the groundwater depth in the arid regions has been presented. The spatial and temporal change of vegetation states in lower reaches of Tarim River under the ecological water transpiration have been discussed by using NDVI data derived from SPOT VEGETATION (VGT) NDVI S10 time sequence image data for the year 1999, 2003 and 2006. It is found that the groundwater depth played a dominant role in determining vegetation growth status in the lower reaches of the Tarim River. After the ecological water transportation, the vegetation has been restored in both sides of the watercourse stretching to Taitema Lake, which extend to 3 km in Akedun section, but decline along the stream flow as 1km in Kaogan section. However the area, which is 3km to 15km away from watercourse, has not been influenced obviously. And the area far away (excess 15km) has no influence. Statistic analysis shows that the groundwater depth has negative relationship with NDVI. And the groundwater depth in lower reaches of Tarim River has been successfully inversed through the statistic method; the simulation precision is 75%.

Shen, Qi; Chen, Yaning; Xu, Jianhua; Zhang, Yan

2008-10-01

216

The REACH 2010 logic model: an illustration of expected performance.  

PubMed

The Centers for Disease Control and Prevention (CDC) supports 40 Racial and Ethnic Approaches to Community Health (REACH 2010) community coalitions in designing, implementing, and evaluating community-driven strategies to eliminate health disparities in racial and ethnic groups. The REACH 2010 logic model was developed to assist grantees in identifying, documenting, and evaluating local attributes of the coalition and its partners to reduce and eliminate local health disparities. The model emphasizes the program's theory of change for addressing health disparities; it displays five distinct stages of evaluation for which qualitative and quantitative measurement data are collected. The CDC is relying on REACH 2010 grantees to provide credible evidence that explains how community contributions have changed conditions and behaviors, thus leading to the reduction and elimination of health disparities. PMID:16356374

Tucker, Pattie; Liao, Youlian; Giles, Wayne H; Liburd, Leandris

2006-01-01

217

Reaching Out, Reaching In  

ERIC Educational Resources Information Center

In this article, the author describes the intergenerational service-learning program at South Scranton Intermediate School in Scranton, Pennsylvania. Currently in its fifth year of operation, the program was originated by William King, a former principal, as an attempt to develop a working relationship between Oakwood Terrace, an Alzheimer's care…

Wren, David J.

2004-01-01

218

Designing and drilling extended reach wells. Part 2  

SciTech Connect

One of the most important issues in the planning and successful drilling of an extended-reach well is well path design. During the last 40 years, the principal forces driving directional well path design have been: doglegs; drill pipe contact force across the build section; drillstring torque and drag; drill pipe buckling; hole cleaning; mechanical well bore stability; and well path tortuosity. Obviously, other concerns have influenced well path design, but an understanding of these issues has been a prerequisite to the successful construction of world class extended reach well bores. This paper reviews these issues.

Guild, G.J.; Hill, T.H.; Summers, M.A. (T H Hill Associates, Houston, TX (United States))

1995-01-01

219

Creating HoPE: Mental Health in Western Australian Maximum Security Prisons  

Microsoft Academic Search

The status of prisoners' mental health has wide-reaching implications for prison inmates, prison authorities and institutions, and the general community. This article presents the mental health findings from the 2008 Health of Prisoner Evaluation (HoPE) pilot project in which 146 maximum security prisoners were interviewed across two prisons in Western Australia. Results revealed significant discrepancies across gender and Indigenous status

Jennifer Fleming; Natalie Gately; Sharan Kraemer

2012-01-01

220

Creating HoPE: Mental Health in Western Australian Maximum Security Prisons  

Microsoft Academic Search

The status of prisoners' mental health has wide-reaching implications for prison inmates, prison authorities and institutions, and the general community. This article presents the mental health findings from the 2008 Health of Prisoner Evaluation (HoPE) pilot project in which 146 maximum security prisoners were interviewed across two prisons in Western Australia. Results revealed significant discrepancies across gender and Indigenous status

Jennifer Fleming; Natalie Gately; Sharan Kraemer

2011-01-01

221

Controlling pulsatile jet formation number with variable diameter exit nozzle for maximum impulse generation  

Microsoft Academic Search

Both jellyfish and Squid propel themselves by ejecting high momentum vortex rings. A set of vortex ring generating thrusters were developed and tested for application in underwater vehicle propulsion. Vortex rings generated from a steady piston cylinder mechanism have a universal formation time, known as the formation number (Gharib et al. 1998), associated with reaching maximum circulation, where the vortex

Mike Krieg; Tyler Thomas; Kamran Mohseni

2009-01-01

222

Effects of Pictorial Cues on Reaching Depend on the Distinctiveness of Target Objects  

PubMed Central

There is an ongoing debate under what conditions learned object sizes influence visuomotor control under preserved stereovision. Using meaningful objects (matchboxes of locally well-known brands in the UK) a previous study has nicely shown that the recognition of these objects influences action programming by means of reach amplitude and grasp pre-shaping even under binocular vision. Using the same paradigm, we demonstrated that short-term learning of colour-size associations was not sufficient to induce any visuomotor effects under binocular viewing conditions. Now we used the same matchboxes, for which the familiarity effect was shown in the UK, with German participants who have never seen these objects before. We addressed the question whether simply a high degree of distinctness, or whether instead actual prior familiarity of these objects, are required to affect motor computations. We found that under monocular and binocular viewing conditions the learned size and location influenced the amplitude of the reaching component significantly. In contrast, the maximum grip aperture remained unaffected for binocular vision. We conclude that visual distinctness is sufficient to form reliable associations in short-term learning to influence reaching even for preserved stereovision. Grasp pre-shaping instead seems to be less susceptible to such perceptual effects.

Himmelbach, Marc

2013-01-01

223

Laplacian eigenvalues and the maximum cut problem  

Microsoft Academic Search

We introduce and study an eigenvalue upper bound?(G) on the maximum cut mc (G) of a weighted graph. The function?(G) has several interesting properties that resemble the behaviour of mc (G). The following results are presented.

Charles Delorme; Svatopluk Poljak

1993-01-01

224

Density estimation by maximum quantum entropy.  

National Technical Information Service (NTIS)

A new Bayesian method for non-parametric density estimation is proposed, based on a mathematical analogy to quantum statistical physics. The mathematical procedure is related to maximum entropy methods for inverse problems and image reconstruction. The in...

R. N. Silver T. Wallstrom H. F. Martz

1993-01-01

225

Entropy Maximum Principle and Instantaneous Failure Statistics.  

National Technical Information Service (NTIS)

A Shannon entropy for instantaneous failure statistics is defined in terms of an integral over the full epoch of possible failure times. An entropy maximum principle subject only to the normalization of the probability density integral and the existence o...

S. Teitler, A. K. Rajagopal, K. L. Ngai

1984-01-01

226

Maximum a Posteriori Filtering and Smoothing Algorithms.  

National Technical Information Service (NTIS)

The paper presents the approximate solution of the non-linear two-point boundary value problem for maximum a posteriori estimation. Filtering, fixed point smoothing, fixed interval smoothing, and fixed lag smoothing algorithms are obtained by the discrete...

A. P. Sage

1969-01-01

227

5 CFR 534.203 - Maximum stipends.  

Code of Federal Regulations, 2010 CFR

...L-2 Second year college undergraduate ...L-3 Third year college undergraduate ...L-4 Fourth year college undergraduate ...1 The maximum money amount in...agency may pay a student-employee a...Office of Personnel Management has...

2010-01-01

228

5 CFR 534.203 - Maximum stipends.  

Code of Federal Regulations, 2010 CFR

...L-2 Second year college undergraduate ...L-3 Third year college undergraduate ...L-4 Fourth year college undergraduate ...1 The maximum money amount in...agency may pay a student-employee a...Office of Personnel Management has...

2009-01-01

229

A dual method for maximum entropy restoration  

NASA Technical Reports Server (NTRS)

A simple iterative dual algorithm for maximum entropy image restoration is presented. The dual algorithm involves fewer parameters than conventional minimization in the image space. Minicomputer test results for Fourier synthesis with inadequate phantom data are given.

Smith, C. B.

1979-01-01

230

The reach and impact of social marketing and reproductive health communication campaigns in Zambia  

PubMed Central

Background Like many sub-Saharan African countries, Zambia is dealing with major health issues, including HIV/AIDS, family planning, and reproductive health. To address reproductive health problems and the HIV/AIDS epidemic in Zambia, several social marketing and health communication programs focusing on reproductive and HIV/AIDS prevention programs are being implemented. This paper describes the reach of these programs and assesses their impact on condom use. Methods This paper assesses the reach of selected radio and television programs about family planning and HIV/AIDS and of communications about the socially marketed Maximum condoms in Zambia, as well as their impact on condom use, using data from the 2001–2002 Zambia Demographic and Health Survey. To control for self-selection and endogeneity, we use a two-stage regression model to estimate the effect of program exposure on the behavioural outcomes. Results Those who were exposed to radio and television programs about family planning and HIV/AIDS were more likely to have ever used a condom (OR = 1.16 for men and 1.06 for women). Men highly exposed to Maximum condoms social marketing communication were more likely than those with low exposure to the program to have ever used a condom (OR = 1.48), and to have used a condom at their last sexual intercourse (OR = 1.23). Conclusion Findings suggest that the reproductive health and social marketing campaigns in Zambia reached a large portion of the population and had a significant impact on condom use. The results suggest that future reproductive health communication campaigns that invest in radio programming may be more effective than those investing in television programming, and that future campaigns should seek to increase their impact among women, perhaps by focusing on the specific constrains that prevent females from using condoms.

Van Rossem, Ronan; Meekers, Dominique

2007-01-01

231

Flood Frequency Analysis using different flood descriptors - the Warsaw reach of the river Vistula case study  

NASA Astrophysics Data System (ADS)

Flood frequency analysis (FFA) is customarily performed using annual maximum flows. However, there is a number of different flood descriptors that could be used. Among them are water levels, peaks over the threshold, flood-wave duration, flood volume, etc. In this study we compare different approaches to FFA for their suitability for flood risk assessment. The main goal is to obtain the FFA curve with the smallest possible uncertainty limits, in particular for the distribution tail. The extrapolation of FFA curves is crucial in future flood risk assessment in a changing climate. We compare the FFA curves together with their uncertainty limits obtained using flows, water levels, flood inundation area and volumes for the Warsaw reach of the river Vistula. Moreover, we derive the FFA curves obtained using simulated flows. The results are used to derive the error distribution for the maximum simulated and observed values under different modelling techniques and assess its influence on flood risk predictions for ungauged catchments. MIKE11, HEC-RAS and transfer function model are applied in average and extreme conditions to model flow propagation in the Warsaw Vistula reach. The additional questions we want to answer are what is the range of application of different modelling tools under various flow conditions and how can the uncertainty of flood risk assessment be decreased. This work was partly supported by the projects "Stochastic flood forecasting system (The River Vistula reach from Zawichost to Warsaw)" and "Modern statistical models for analysis of flood frequency and features of flood waves", carried by the Institute of Geophysics, Polish Academy of Sciences on the order of the National Science Centre (contracts Nos. 2011/01/B/ST10/06866 and 2012/05/B/ST10/00482, respectively). The water level and flow data were provided by the Institute of Meteorology and Water Management (IMGW), Poland.

Karamuz, Emilia; Kochanek, Krzysztof; Romanowicz, Renata

2014-05-01

232

Minority Health Surveillance -- REACH U.S., 2009  

MedlinePLUS

... Health Surveillance- REACH U.S. 2009 Substantial racial/ethnic health disparities exist in the United States. Although racial/ethnic minorities are growing at a rapid pace, large-scale community-based surveys and ... status of minority populations are limited. The Racial ...

233

Out of Reach? Latinos, Education and Technology in California.  

ERIC Educational Resources Information Center

The Tomas Rivera Policy Institute conducted research to clarify the state of technology development in schools in San Bernardino and Los Angeles counties, California and to determine whether meaningful technology access was out of reach for those school districts in which the enrollment was predominantly Hispanic. The empirical investigation, with…

Wilhelm, Tony; Ladd, Michelle, Ed.

234

Reaching Higher Ground: Parental Outreach Programs at the Postsecondary Level  

ERIC Educational Resources Information Center

In this follow-up study to "College Knowledge: What Latino Parents Need to Know and Why They Don't Know It," [see ED469295], the Tomas Rivera Policy Institute examines how postsecondary institutions are mobilizing to address the need for college information among Latino parents. The primary objective of "Reaching Higher Ground" is to profile in…

Torres, Celina; Marquez, Amalia

2005-01-01

235

Overlapping representations for grip type and reach direction.  

PubMed

To grasp an object, we need to move the arm toward it and assume the appropriate hand configuration. While previous studies suggested dorsomedial and dorsolateral pathways in the brain specialized respectively for the transport and grip components, more recent studies cast doubt on such a clear-cut distinction. It is unclear, however, to which degree neuronal populations selective for the two components overlap, and if so, to which degree they interact. Here, we used multivoxel pattern analysis (MVPA) of functional magnetic resonance imaging (fMRI) data to investigate the representation of three center-out movements (touch, pincer grip, whole-hand grip) performed in five reach directions. We found selectivity exclusively for reach direction in posterior and rostral superior parietal lobes (SPLp, SPLr), supplementary motor area (SMA), and the superior portion of dorsal premotor cortex (PMDs). Instead, we found selectivity for both grip type and reach direction in the inferior portion of dorsal premotor cortex (PMDi), ventral premotor cortex (PMv), anterior intraparietal sulcus (aIPS), primary motor (M1), somatosensory (S1) cortices and the anterior superior parietal lobe (SPLa). Within these regions, PMv, M1, aIPS and SPLa showed weak interactions between the transport and grip components. Our results suggest that human PMDi and S1 contain both grip- and reach-direction selective neuronal populations that retain their functional independence, whereas this information might be combined at the level of PMv, M1, aIPS, and SPLa. PMID:24650596

Fabbri, Sara; Strnad, Lukas; Caramazza, Alfonso; Lingnau, Angelika

2014-07-01

236

Brood ecology of Canada geese on the Hanford Reach  

SciTech Connect

The objective was to examine the ecology of broods of the western Canada goose (Branta canadensis moffitti) on the Hanford Reach of the Columbia River in southcentral Washington. Broods were captured and equipped with radio transmitters and their movements tracked. Major brood rearing areas were identified. 5 references, 2 tables. (ACR)

Eberhardt, L.E.

1983-12-01

237

The statistical determinants of adaptation rate in human reaching  

PubMed Central

Rapid reaching to a target is generally accurate but also contains random and systematic error. Random errors result from noise in visual measurement, motor planning, and reach execution. Systematic error results from systematic changes in the mapping between the visual estimate of target location and the motor command necessary to reach the target (e.g., new spectacles, muscular fatigue). Humans maintain accurate reaching by recalibrating the visuomotor system, but no widely accepted computational model of the process exists. Given certain boundary conditions, a statistically optimal solution is a Kalman filter. We compared human to Kalman filter behavior to determine how humans take into account the statistical properties of errors and the reliability with which those errors can be measured. For most conditions, human and Kalman filter behavior was similar: Increasing measurement uncertainty caused similar decreases in recalibration rate; directionally asymmetric uncertainty caused different rates in different directions; more variation in systematic error increased recalibration rate. However, behavior differed in one respect: Inserting random error by perturbing feedback position causes slower adaptation in Kalman filters but had no effect in humans. This difference may be due to how biological systems remain responsive to changes in environmental statistics. We discuss the implications of this work.

Burge, Johannes; Ernst, Marc O.; Banks, Martin S.

2009-01-01

238

Now and Then: The U.S. Reaches 300 Million  

ERIC Educational Resources Information Center

Today, the Census Bureau compiles extensive information every year about the people and the economy of the United States. That is how the authors know that in 2006 the United States is going to reach an extraordinary milestone--300 million people. In this article, the authors discuss the "now and then" of the U.S. society. The authors observed…

Waldrop, Judith; Crews, Kimberly

2006-01-01

239

MIDDLE REACH OF THE SNAKE RIVER: WATER QUALITY MONITORING  

EPA Science Inventory

The purpose of the project was to collect, analyze, assemble, and assess water quality data and resulting chemical/nutrient loads entering and transported in the Middle Snake River Reach of Idaho, between Milner Dam and King Hill. Studies were conducted during the period of 1990 ...

240

Priming of Reach and Grasp Actions by Handled Objects  

ERIC Educational Resources Information Center

Pictures of handled objects such as a beer mug or frying pan are shown to prime speeded reach and grasp actions that are compatible with the object. To determine whether the evocation of motor affordances implied by this result is driven merely by the physical orientation of the object's handle as opposed to higher-level properties of the object,…

Masson, Michael E. J.; Bub, Daniel N.; Breuer, Andreas T.

2011-01-01

241

14. RAILROAD BRIDGE MISSISSIPPI, MONROE CO., ABERDEEN Reach by foot ...  

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

14. RAILROAD BRIDGE MISSISSIPPI, MONROE CO., ABERDEEN Reach by foot from E end of Vine St. St. Louis and San Francisco RR bridge. Bridge built 1887, replaced, 1969. Credit: Evans Memorial Library, Aberdeen, Ms. No date. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

242

REACH. Teacher's Guide, Volume I. Post-Secondary Program Management.  

ERIC Educational Resources Information Center

Designed for use with individualized instruction units (CE 026 345-347, and CE 026 349-351) in the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this first volume of the postsecondary teacher's guide is devoted to the establishment of standard instructional procedures. Following an introductory…

Morris, James Lee; And Others

243

REACH. Teacher's Guide, Volume I. Secondary Program Management.  

ERIC Educational Resources Information Center

Designed for use with individualized instructional units (CE 026 345 and CE 026 348-350) in the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this secondary teacher's guide is devoted to the establishment of standard instructional procedures. Following an introductory section, sections provide…

Morris, James Lee; And Others

244

Posterior cortical atrophy: visuomotor deficits in reaching and grasping  

PubMed Central

Posterior Cortical Atrophy (PCA) is a rare clinical syndrome characterized by the predominance of higher-order visual disturbances such as optic ataxia, a characteristic of Balint's syndrome. Deficits result from progressive neurodegeneration of occipito-temporal and occipito-parietal cortices. The current study sought to explore the visuomotor functioning of four individuals with PCA by testing their ability to reach out and grasp real objects under various viewing conditions. Experiment 1 had participants reach out and grasp simple, rectangular blocks under visually- and memory-guided conditions. Experiment 2 explored participants' abilities to accurately reach for objects located in their visual periphery. This investigation revealed that PCA patients demonstrate many of the same deficits that have been previously reported in other individuals with optic ataxia, such as “magnetic misreaching”—a pathological reaching bias toward the point of visual fixation when grasping peripheral targets. Unlike many other individuals with optic ataxia, however, the patients in the current study also show symptoms indicative of damage to the more perceptual stream of visual processing, including abolished grip scaling during memory-guided grasping and deficits in face and object identification. These investigations are the first to perform a quantitative analysis of the visuomotor deficits exhibited by patients with PCA. Critically, this study helps characterize common symptoms of PCA, a vital first step for generating effective diagnostic criteria and therapeutic strategies for this understudied neurodegenerative disorder.

Meek, Benjamin P.; Shelton, Paul; Marotta, Jonathan J.

2013-01-01

245

Simulating the Cortical 3D Visuomotor Transformation of Reach Depth  

PubMed Central

We effortlessly perform reach movements to objects in different directions and depths. However, how networks of cortical neurons compute reach depth from binocular visual inputs remains largely unknown. To bridge the gap between behavior and neurophysiology, we trained a feed-forward artificial neural network to uncover potential mechanisms that might underlie the 3D transformation of reach depth. Our physiologically-inspired 4-layer network receives distributed 3D visual inputs (1st layer) along with eye, head and vergence signals. The desired motor plan was coded in a population (3rd layer) that we read out (4th layer) using an optimal linear estimator. After training, our network was able to reproduce all known single-unit recording evidence on depth coding in the parietal cortex. Network analyses predict the presence of eye/head and vergence changes of depth tuning, pointing towards a gain-modulation mechanism of depth transformation. In addition, reach depth was computed directly from eye-centered (relative) visual distances, without explicit absolute depth coding. We suggest that these effects should be observable in parietal and pre-motor areas.

Blohm, Gunnar

2012-01-01

246

Simulating the cortical 3D visuomotor transformation of reach depth.  

PubMed

We effortlessly perform reach movements to objects in different directions and depths. However, how networks of cortical neurons compute reach depth from binocular visual inputs remains largely unknown. To bridge the gap between behavior and neurophysiology, we trained a feed-forward artificial neural network to uncover potential mechanisms that might underlie the 3D transformation of reach depth. Our physiologically-inspired 4-layer network receives distributed 3D visual inputs (1(st) layer) along with eye, head and vergence signals. The desired motor plan was coded in a population (3(rd) layer) that we read out (4(th) layer) using an optimal linear estimator. After training, our network was able to reproduce all known single-unit recording evidence on depth coding in the parietal cortex. Network analyses predict the presence of eye/head and vergence changes of depth tuning, pointing towards a gain-modulation mechanism of depth transformation. In addition, reach depth was computed directly from eye-centered (relative) visual distances, without explicit absolute depth coding. We suggest that these effects should be observable in parietal and pre-motor areas. PMID:22815979

Blohm, Gunnar

2012-01-01

247

The Effects of Motivational Graphing on Students Reaching Educational Goals  

ERIC Educational Resources Information Center

The purpose of this research project was to conclude if motivational graphing strategies, when used in Math Response to Intervention (RTI) classes, could increase the students' ability to reach their goals. To complete this investigation the researcher assessed the Math RTI students' ability to count orally within one minute on a biweekly basis.…

Graves, Loren Adair

2011-01-01

248

Within Our Reach: How America Can Educate Every Child  

ERIC Educational Resources Information Center

The No Child Left Behind Act (NCLB) is bolder than all previous federal education laws, setting ambitious goals for universal student achievement and authorizing severe remedies for schools not reaching them. In a nation where most youngsters are far from proficient in reading and mathematics and where innumerable efforts to boost learning levels…

Chubb, John E.

2005-01-01

249

Perceiving Children's Behavior and Reaching Limits in a Risk Environment  

ERIC Educational Resources Information Center

The purpose of this study was to investigate the accuracy of parents' perception of children's reaching limits in a risk scenario. A sample of 68 parents of 1- to 4-year-olds were asked to make a prior estimate of their children's behavior and action limits in a task that involved retrieving a toy out of the water. The action modes used for…

Cordovil, Rita; Santos, Carlos; Barreiros, Joao

2012-01-01

250

Reaching Approximate Agreement in the Presence of Faults  

Microsoft Academic Search

This paper considers a variant on the Byzantine Generals problem, in which processes start with arbitrary real values rather than Boolean values or values from some bounded range, and in which approximate, rather than exact, agreement is the desired goal. Algorithms are presented to reach approximate agreement in asynchronous, as well as synchronous systems. The asynchronous agreement algorithm is an

Danny Dolev; Nancy A. Lynch

1985-01-01

251

Reaching approximate agreement in the presence of faults  

Microsoft Academic Search

This paper considers a variant of the Byzantine Generals problem, in which processes start with arbitrary real values rather than Boolean values or values from some bounded range, and in which approximate, rather than exact, agreement is the desired goal. Algorithms are presented to reach approximate agreement in asynchronous, as well as synchronous systems. The asynchronous agreement algorithm is an

Danny Dolev; Nancy A. Lynch; Shlomit S. Pinter; Eugene W. Stark; William E. Weihl

1986-01-01

252

Hydraulic characterization of the middle reach of the Congo River  

NASA Astrophysics Data System (ADS)

The middle reach of the Congo remains one of the most difficult places to access, with ongoing conflicts and a lack of infrastructure. This has resulted in the Congo being perhaps the least understood large river hydraulically, particularly compared to the Amazon, Nile, or Mississippi. Globally the Congo River is important; it is the largest river in Africa and the basin contains some of the largest areas of tropical forests and wetlands in the world, which are important to both the global carbon and methane cycles. This study produced the first detailed hydraulic characterization of the middle reach, utilizing mostly remotely sensed data sets. Using Landsat imagery, a 30 m resolution water-mask was created for the middle reach, from which effective river widths and the number of channels and islands were determined. Water surface slopes were determined using ICESat observations for three different periods during the annual flood pulse, and while the overall slope calculated was similar to previous estimates, greater spatial variability was identified. We find that the water surface slope varies markedly in space but relatively little in time and that this appears to contrast with the Amazon where previous studies indicate that time and spatial variations are of equal magnitude. Five key hydraulic constraints were also identified, which play an important role in the overall dynamics of the Congo. Finally, backwater lengths were approximated for four of these constraints, with the results showing that at high water, over a third of the middle reach is affected by backwater effects.

O'Loughlin, F.; Trigg, M. A.; Schumann, G. J.-P.; Bates, P. D.

2013-08-01

253

Discovery mass reach for excited quarks at hadron colliders  

SciTech Connect

If quarks are composite particles then excited states are expected. We estimate the discovery mass reach as a function of integrated luminosity for excited quarks decaying to dijets at the Tevatron the mass reach is 0.94 TeV for Run 11 (2 fb{sup -1}) and 1. 1 TeV for TeV33 (30 fb{sup -1}). At the LHC the mass reach is 6.3 TeV for 100 fb{sup -1}. At a VLHC with a center of mass energy {radical}s, of 50 TeV (200 TeV) the mass reach is 25 TeV (78 TeV) for an integrated luminosity of 10{sup 4} fb{sup -1}. However, an excited quark with a mass of 25 TeV would be discovered at a hadron collider with {radical}s = 100 TeV and an integrated luminosity of 13 fb{sup -1}, illustrating a physics example where a factor of 2 in machine energy is worth a factor of 1000 in luminosity.

Harris, R.M.

1996-09-10

254

Reaching a Moveable Visual Target: Dissociations in Brain Tumour Patients  

ERIC Educational Resources Information Center

Damage to the posterior parietal cortex (PPC) can lead to Optic Ataxia (OA), in which patients misreach to peripheral targets. Recent research suggested that the PPC might be involved not only in simple reaching tasks toward peripheral targets, but also in changing the hand movement trajectory in real time if the target moves. The present study…

Buiatti, Tania; Skrap, Miran; Shallice, Tim

2013-01-01

255

Is There Directed Reaching in the Human Neonate?  

ERIC Educational Resources Information Center

A replication study of directed reaching in children. In response to a visual stimulus the arm and hand movements of infants were videotaped and analyzed to determine whether the position of the ball affected the direction of the infants' extensions. (Author/SS)

Ruff, Holly A.; Halton, Antonia

1978-01-01

256

Meet Marsha William: In Arms Reach Home Day Care  

ERIC Educational Resources Information Center

Confident in what she knows, excited about what she's learning, eager to share her passion with others--this is Marsha Williams, director of In Arms Reach Home Day Care, Baltimore, Maryland. She enjoys being a family care provider, because with no more than eight children, she manages to give more individualized attention on a daily basis. She…

Exchange: The Early Childhood Leaders' Magazine Since 1978, 2006

2006-01-01

257

The influence of object identity on obstacle avoidance reaching behaviour.  

PubMed

When reaching for target objects, we hardly ever collide with other objects located in our working environment. Behavioural studies have demonstrated that the introduction of non-target objects into the workspace alters both spatial and temporal parameters of reaching trajectories. Previous studies have shown the influence of spatial object features (e.g. size and position) on obstacle avoidance movements. However, obstacle identity may also play a role in the preparation of avoidance responses as this allows prediction of possible negative consequences of collision based on recognition of the obstacle. In this study we test this hypothesis by asking participants to reach towards a target as quickly as possible, in the presence of an empty or full glass of water placed about half way between the target and the starting position, at 8cm either left or right of the virtual midline. While the spatial features of full and empty glasses of water are the same, the consequences of collision are clearly different. Indeed, when there was a high chance of collision, reaching trajectories veered away more from filled than from empty glasses. This shows that the identity of potential obstacles, which allows for estimating the predicted consequences of collision, is taken into account during obstacle avoidance. PMID:24859673

de Haan, A M; Van der Stigchel, S; Nijnens, C M; Dijkerman, H C

2014-07-01

258

ENVISAT altimetry over narrow reaches of the Amazon basin contributors  

NASA Astrophysics Data System (ADS)

The lower limit in river width of the capability of radar altimetry to retrieve river stages is still a matter of debate. The Amazon basin includes rivers of all size, from as wide as several kilometers to as narrow as a few tens of meters. We have derived ~500 series in this basin over the entire range of reach widths. In the present study, we analyze the quality of these series with respect to the reach width criterion. We show that high quality series (rms error around 20 cm) can be retrieved even for reaches as narrow as 100m, as well as for km wide reaches. Such a result suggests that in a basin such as the Amazon basin, even more valuable series could be derived, probably more than a thousand. Such a dataset of water stages densely distributed throughout the basin is clearly a major dataset for any kind of study dealing with the hydrology of the Amazon basin. A preliminary test with a few series derived in the Congo basin suggests that similar results can be expected for this basin, too.

Silva, J. S.; Calmant, S.; Seyler, F.; Research Team Of Rhasa

2013-05-01

259

Reaching and Grasping Movements in Infants at Risk: A Review  

ERIC Educational Resources Information Center

Although the influence of intrinsic and extrinsic factors on the development of reaching and grasping skills in typical infants has been extensively described in the literature, the effect of such factors on at-risk infants is still poorly understood. Therefore, the aims of the present study were to analyze the scientific publications, from 1980…

de Campos, Ana Carolina; Rocha, Nelci Adriana Cicuto Ferreira; Savelsbergh, Geert J. P.

2009-01-01

260

Learning of Visuomotor Transformations for Vectorial Planning of Reaching Trajectories  

Microsoft Academic Search

The planning of visually guided reaches is accomplished by independent specification of extent and direction. We investi- gated whether this separation of extent and direction planning for well practiced movements could be explained by differences in the adaptation to extent and directional errors during motor learning. We compared the time course and generalization of adaptation with two types of screen

John W. Krakauer; Zachary M. Pine; Maria-Felice Ghilardi; Claude Ghez

2000-01-01

261

Reaching Part-Time Distance Students in Diverse Environments  

ERIC Educational Resources Information Center

This article focuses on the model used at the University of Kansas Medical Center to reach graduate students in the School of Nursing. Like many students returning for graduate degrees, distance students are balancing the demands of professional positions, graduate studies, and family life. Topics addressed include: point-of-need assistance,…

Whitehair, Kristin J.

2010-01-01

262

Control of reaching movements by muscle synergy combinations  

PubMed Central

Controlling the movement of the arm to achieve a goal, such as reaching for an object, is challenging because it requires coordinating many muscles acting on many joints. The central nervous system (CNS) might simplify the control of reaching by directly mapping initial states and goals into muscle activations through the combination of muscle synergies, coordinated recruitment of groups of muscles with specific activation profiles. Here we review recent results from the analysis of reaching muscle patterns supporting such a control strategy. Muscle patterns for point-to-point movements can be reconstructed by the combination of a small number of time-varying muscle synergies, modulated in amplitude and timing according to movement directions and speeds. Moreover, the modulation and superposition of the synergies identified from point-to-point movements captures the muscle patterns underlying multi-phasic movements, such as reaching through a via-point or to a target whose location changes after movement initiation. Thus, the sequencing of time-varying muscle synergies might implement an intermittent controller which would allow the construction of complex movements from simple building blocks.

d'Avella, Andrea; Lacquaniti, Francesco

2013-01-01

263

Reaching Rural Communities: Increasing Access to Disability Research Information.  

ERIC Educational Resources Information Center

Nonmetropolitan areas have the highest percentage of people with disabilities, including severe disabilities. However, rural people with disabilities may represent a population that is underserved or difficult to reach. Barriers to information dissemination in rural areas include limited transportation and communications infrastructures, greater…

Research Exchange, 2002

2002-01-01

264

Maximum forces and deflections from orthodontic appliances.  

PubMed

The maximum bending moment of an orthodontic wire is an important parameter in the design and use of an orthodontic appliance. It is the wire property that determines how much force an appliance can deliver. A bending test which allows direct measurement of the maximum bending moment was developed. Data produced from this test are independent of wire length and configuration. The maximum bending moment, percent recovery, and maximum springback were determined for round and rectangular cross sections of stainless steel, nickel-titanium, and beta-titanium wires. The data suggest the need for more specifically defining maximum moment and maximum springback. Three maximum bending moments are described: Me, My, and Mult. My and Mult are clinically the most significant. Appliances that are required to have no permanent deformation must operate below My. Appliances that exhibit marked permanent deformation may be used in some applications and, if so, higher bending moments can be produced. In order of magnitude, the maximum bending moment at yield is largest in stainless steel, beta-titanium, and nickel-titanium for a given cross section. Nickel-titanium and beta-titanium have significantly larger springback than stainless steel determined at the moment at yield. Nickel-titanium did not follow the theoretical ratio between ultimate bending moment and the bending moment at yield, exhibiting a very large ratio. The study supports the hypothesis that most orthodontic appliances are activated in a range where both plastic and elastic behavior occurs; therefore, the use of yield strengths for calculation of force magnitude can lead to a significant error in predicting the forces delivered. PMID:6576645

Burstone, C J; Goldberg, A J

1983-08-01

265

Maximum, Minimum, and Current Temperature Protocol  

NSDL National Science Digital Library

The purpose of this activity is to measure air (and optionally soil) temperature within one hour of solar noon and the maximum and minimum air temperatures for the previous 24 hours. Intended outcomes are that students will learn to read minimum, maximum, and current temperatures using a U-shaped thermometer, understand diurnal and annual temperature variations, and recognize factors that influence atmospheric temperatures. Supporting background materials for both student and teacher are included.

The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

2003-08-01

266

Reaching for the Sky: The Growth of Mountain Tourism in Switzerland.  

ERIC Educational Resources Information Center

Addresses the beginnings of Swiss tourism, its barriers, and the development and role of transportation in mountain tourism. Considers the environmental problems caused by mountain tourism in Switzerland and provides seven teaching ideas. (CMK)

Rothwell, Jennifer Truran

1999-01-01

267

Reaching Every Reader: Promotional Strategies for the Elementary School Library Media Specialist. Professional Growth Series.  

ERIC Educational Resources Information Center

This book is designed for overextended librarians and for those who are looking for fresh approaches to what they have been doing for years. The intent in the book is to incorporate traditional techniques, such as storytelling and puppetry, with the use of technology, particularly the Internet--many different learning styles are incorporated to…

Miller, Pat

268

Neuronal synchronization in human posterior parietal cortex during reach planning.  

PubMed

Although single-unit studies in monkeys have identified effector-related regions in the posterior parietal cortex (PPC) during saccade and reach planning, the degree of effector specificity of corresponding human regions, as established by recordings of the blood oxygen level-dependent signal, is still under debate. Here, we addressed this issue from a different perspective, by studying the neuronal synchronization of the human PPC during both reach and saccade planning. Using magnetoencephalography (MEG), we recorded ongoing brain activity while subjects performed randomly alternating trials of memory-guided reaches or saccades. Additionally, subjects performed a dissociation task requiring them to plan both a memory-guided saccade and reach to locations in opposing visual hemifields. We examined changes in spectral power of the MEG signal during a 1.5 s memory period in relation to target location (left/right) and effector type (eye/hand). The results show direction-selective synchronization in the 70-90 Hz gamma frequency band, originating from the medial aspect of the PPC, when planning a reaching movement. In contrast, activity in a more central portion of the PPC was synchronized in a lower gamma band (50-60 Hz) when planning the direction of a saccade. Both observations were corroborated in the dissociation task. In the lower frequency bands, we observed sustained alpha-band (8-12 Hz) desynchronization in occipitoparietal regions, but in an effector-unspecific manner. These results suggest that distinct modules in the posterior parietal cortex encode movement goals of different effectors by selective gamma-band activity, compatible with the functional organization of monkey PPC. PMID:20107066

Van Der Werf, Jurrian; Jensen, Ole; Fries, Pascal; Medendorp, W Pieter

2010-01-27

269

Role of TNF alpha and PLF in bone remodeling in a rat model of repetitive reaching and grasping  

PubMed Central

We have previously developed a voluntary rat model of highly repetitive reaching that provides an opportunity to study effects of non-weight bearing muscular loads on bone and mechanisms of naturally occurring inflammation on upper limb tissues in vivo. In this study, we investigated the relationship between inflammatory cytokines and matricellular proteins (Periostin-like-factor, PLF, and connective tissue growth factor, CTGF) using our model. We also examined the relationship between inflammatory cytokines, PLF and bone formation processes. Rats underwent initial training for 5 weeks, and then performed a high repetition high force (HRHF) task (12 reaches/min, 60% maximum grip force, 2 hr/day, 3 days/week) for 6 weeks. We then examined the effect of training or task performance with or without treatment with a rat specific TNF? antibody on inflammatory cytokines, osteocalcin (a bone formation marker), PLF, CTGF, and behavioral indicators of pain or discomfort. The HRHF task decreased grip strength and induced forepaw mechanical hypersensitivity in both trained control and 6-week HRHF animals. Two weeks of anti-TNF? treatment improved grip strength in both groups, but did not ameliorate forepaw hypersensitivity. Moreover, anti-TNF? treatment attenuated task-induced increases in inflammatory cytokines (TNF?, IL-1?, and MIP2 in serum; TNF? in forelimb bone and muscles) and serum osteocalcin in 6-week HRHF animals. PLF levels in forelimb bones and flexor digitorum muscles increased significantly in 6-week HRHF animals, increases attenuated by anti-TNF? treatment. CTGF levels were unaffected by task performance or anti-TNF? treatment in 6-week HRHF muscles. In primary osteoblast cultures, TNF?, MIP2 and MIP3a treatment increased PLF levels in a dose dependent manner. Also in primary osteoblast cultures, increased PLF promoted proliferation and differentiation, the latter assessed by measuring Runx2, alkaline phosphatase (ALP) and osteocalcin mRNA levels; ALP activity; as well as calcium deposition and mineralization. Increased PLF also promoted cell adhesion in MC3T3-E1 osteoblast-like cell cultures. Thus, tissue loading in vivo resulted in increased TNF?, which increased PLF, which then induced anabolic bone formation, the latter results confirmed in vitro.

Rani, Shobha; Barbe, Mary F; Barr, Ann E; Litivn, Judith

2011-01-01

270

The development of rapid online control in children aged 6-12 years: reaching performance.  

PubMed

Rapid online control during reaching has an important bearing on movement accuracy and flexibility. It is surprising then that few studies have investigated the development of rapid online control in children. In this study, we were particularly interested in age-related changes in the nature of motor control in response to visual perturbation. We compared the performance of younger (6-7 years of age), mid-aged (8-9), and older (10-12) children, as well as healthy young adults using a double-step reaching task. Participants were required to make target-directed reaching movements in near space, while also responding to visual perturbations that occurred at movement onset for a small percentage of trials. Results showed that both the older and mid-aged children corrected their reaching in response to the unexpected shifts in target location significantly faster than younger children, manifest by reduced time to correction. In turn, the responses of adults were faster than older children in terms of movement time and on kinematic measures such as time to correction and time to peak velocity. These results indicate that the capacity to utilize forward estimates of limb position in the service of online control of early perturbations to ballistic (or rapid) reaching develops in a non-linear fashion, progressing rapidly between early and middle childhood, showing a degree of stability over mid and later childhood, but then evidence for continued refinement between childhood and young adulthood. The pattern of change after childhood and into early adolescence requires further investigation, particularly during the rapid phase of physical growth that accompanies puberty. PMID:23932022

Wilson, Peter H; Hyde, Christian

2013-10-01

271

Coordinated turn-and-reach movements. I. Anticipatory compensation for self-generated coriolis and interaction torques  

NASA Technical Reports Server (NTRS)

When reaching movements involve simultaneous trunk rotation, additional interaction torques are generated on the arm that are absent when the trunk is stable. To explore whether the CNS compensates for such self-generated interaction torques, we recorded hand trajectories in reaching tasks involving various amplitudes and velocities of arm extension and trunk rotation. Subjects pointed to three targets on a surface slightly above waist level. Two of the target locations were chosen so that a similar arm configuration relative to the trunk would be required for reaching to them, one of these targets requiring substantial trunk rotation, the other very little. Significant trunk rotation was necessary to reach the third target, but the arm's radial distance to the body remained virtually unchanged. Subjects reached at two speeds-a natural pace (slow) and rapidly (fast)-under normal lighting and in total darkness. Trunk angular velocity and finger velocity relative to the trunk were higher in the fast conditions but were not affected by the presence or absence of vision. Peak trunk velocity increased with increasing trunk rotation up to a maximum of 200 degrees /s. In slow movements, peak finger velocity relative to the trunk was smaller when trunk rotation was necessary to reach the targets. In fast movements, peak finger velocity was approximately 1.7 m/s for all targets. Finger trajectories were more curved when reaching movements involved substantial trunk rotation; however, the terminal errors and the maximal deviation of the trajectory from a straight line were comparable in slow and fast movements. This pattern indicates that the larger Coriolis, centripetal, and inertial interaction torques generated during rapid reaches were compensated by additional joint torques. Trajectory characteristics did not vary with the presence or absence of vision, indicating that visual feedback was unnecessary for anticipatory compensations. In all reaches involving trunk rotation, the finger movement generally occurred entirely during the trunk movement, indicating that the CNS did not minimize Coriolis forces incumbent on trunk rotation by sequencing the arm and trunk motions into a turn followed by a reach. A simplified model of the arm/trunk system revealed that additional interaction torques generated on the arm during voluntary turning and reaching were equivalent to < or =1.8 g (1 g = 9.81 m/s(2)) of external force at the elbow but did not degrade performance. In slow-rotation room studies involving reaching movements during passive rotation, Coriolis forces as small as 0.2 g greatly deflect movement trajectories and endpoints. We conclude that compensatory motor innervations are engaged in a predictive fashion to counteract impending self-generated interaction torques during voluntary reaching movements.

Pigeon, Pascale; Bortolami, Simone B.; DiZio, Paul; Lackner, James R.

2003-01-01

272

Parieto-frontal coding of reaching: an integrated framework.  

PubMed

In the last few years, anatomical and physiological studies have provided new insights into the organization of the parieto-frontal network underlying visually guided arm-reaching movements in at least three domains. (1) Network architecture. It has been shown that the different classes of neurons encoding information relevant to reaching are not confined within individual cortical areas, but are common to different areas, which are generally linked by reciprocal association connections. (2) Representation of information. There is evidence suggesting that reach-related populations of neurons do not encode relevant parameters within pure sensory or motor "reference frames", but rather combine them within hybrid dimensions. (3) Visuomotor transformation. It has been proposed that the computation of motor commands for reaching occurs as a simultaneous recruitment of discrete populations of neurons sharing similar properties in different cortical areas, rather than as a serial process from vision to movement, engaging different areas at different times. The goal of this paper was to link experimental (neurophysiological and neuroanatomical) and computational aspects within an integrated framework to illustrate how different neuronal populations in the parieto-frontal network operate a collective and distributed computation for reaching. In this framework, all dynamic (tuning, combinatorial, computational) properties of units are determined by their location relative to three main functional axes of the network, the visual-to-somatic, position-direction, and sensory-motor axis. The visual-to-somatic axis is defined by gradients of activity symmetrical to the central sulcus and distributed over both frontal and parietal cortices. At least four sets of reach-related signals (retinal, gaze, arm position/movement direction, muscle output) are represented along this axis. This architecture defines informational domains where neurons combine different inputs. The position-direction axis is identified by the regular distribution of information over large populations of neurons processing both positional and directional signals (concerning the arm, gaze, visual stimuli, etc.) Therefore, the activity of gaze- and arm-related neurons can represent virtual three-dimensional (3D) pathways for gaze shifts or hand movement. Virtual 3D pathways are thus defined by a combination of directional and positional information. The sensory-motor axis is defined by neurons displaying different temporal relationships with the different reach-related signals, such as target presentation, preparation for intended arm movement, onset of movements, etc. These properties reflect the computation performed by local networks, which are formed by two types of processing units: matching and condition units. Matching units relate different neural representations of virtual 3D pathways for gaze or hand, and can predict motor commands and their sensory consequences. Depending on the units involved, different matching operations can be learned in the network, resulting in the acquisition of different visuo-motor transformations, such as those underlying reaching to foveated targets, reaching to extrafoveal targets, and visual tracking of hand movement trajectory. Condition units link these matching operations to reinforcement contingencies and therefore can shape the collective neural recruitment along the three axes of the network. This will result in a progressive match of retinal, gaze, arm, and muscle signals suitable for moving the hand toward the target. PMID:10591906

Burnod, Y; Baraduc, P; Battaglia-Mayer, A; Guigon, E; Koechlin, E; Ferraina, S; Lacquaniti, F; Caminiti, R

1999-12-01

273

A Maximum Likelihood Approach to Estimating Correlation Functions  

NASA Astrophysics Data System (ADS)

We define a maximum likelihood (ML for short) estimator for the correlation function, ?, that uses the same pair counting observables (D, R, DD, DR, RR) as the standard Landy & Szalay (LS for short) estimator. The ML estimator outperforms the LS estimator in that it results in smaller measurement errors at any fixed random point density. Put another way, the ML estimator can reach the same precision as the LS estimator with a significantly smaller random point catalog. Moreover, these gains are achieved without significantly increasing the computational requirements for estimating ?. We quantify the relative improvement of the ML estimator over the LS estimator and discuss the regimes under which these improvements are most significant. We present a short guide on how to implement the ML estimator and emphasize that the code alterations required to switch from an LS to an ML estimator are minimal.

Jones Baxter, Eric; Rozo, Eduardo

2013-12-01

274

Early local last glacial maximum in the tropical Andes.  

PubMed

The local last glacial maximum in the tropical Andes was earlier and less extensive than previously thought, based on 106 cosmogenic ages (from beryllium-10 dating) from moraines in Peru and Bolivia. Glaciers reached their greatest extent in the last glacial cycle approximately 34,000 years before the present and were retreating by approximately 21,000 years before the present, implying that tropical controls on ice volumes were asynchronous with those in the Northern Hemisphere. Our estimates of snowline depression reflect about half the temperature change indicated by previous widely cited figures, which helps resolve the discrepancy between estimates of terrestrial and marine temperature depression during the last glacial cycle. PMID:15860623

Smith, Jacqueline A; Seltzer, Geoffrey O; Farber, Daniel L; Rodbell, Donald T; Finkel, Robert C

2005-04-29

275

Maximum magnitudes in aftershock sequences in Taiwan  

NASA Astrophysics Data System (ADS)

In this work, Båth's Law, the b-value in Gutenberg–Richter Law (G–R Law) in the form of the 1/? relationship, and both the a- and b-values in the G–R Law were introduced in order to estimate maximum aftershock magnitudes of earthquake sequences in the Taiwan region. The averaged difference of magnitude between the mainshock and the maximum aftershock is 1.20, and is consistent with Båth's Law, however, with a large uncertainty. The large uncertainty implies that the difference may result from a variable controlled by other factors, such as the aftershocks number of an earthquake sequence and magnitude threshold for mainshock. With 1/?, since 86% of the earthquake sequences with a M ? 6.0 mainshock follow this relationship, the upper bound of the maximum magnitude can be estimated for an earthquake sequence with a large mainshock. The a- and b-values in the G–R Law was also considered by evaluating maximum aftershock magnitudes. As there are low residuals between the model and the observations, the results suggest that the G–R Law is a good index for maximum aftershock magnitude determinations. In order to evaluate the temporal decays of maximum aftershock magnitudes, modified Omori's Law was introduced. Using the approaches mentioned above, the maximum magnitudes and the temporal evolution of an earthquake sequence could be modeled. Among them, the model of the G–R Law has the best fit with observations for most of earthquake sequences. It shows its feasibility. The results of this work may benefit seismic hazards mitigation in the form of rapid re-evaluations for short-term seismic hazards immediately following devastating earthquakes.

Chan, Chung-Han; Wu, Yih-Min

2013-09-01

276

Reaching to Throw Compared to Reaching to Place: A Comparison across Individuals with and without Developmental Coordination Disorder  

ERIC Educational Resources Information Center

When picking up an object, adults show a longer deceleration phase when the onward action has a greater precision requirement. Tailoring action in this way is thought to need forward modelling in order to predict the consequences of movement. Some evidence suggests that young children also tailor reaching in this way; however, how this skill…

Wilmut, Kate; Byrne, Maia; Barnett, Anna L.

2013-01-01

277

Translating the REACH Caregiver Intervention for Use by Area Agency on Aging Personnel: the REACH OUT Program  

ERIC Educational Resources Information Center

Purpose: The aim of this study was to translate the evidence-based Resources for Enhancing Alzheimer's Caregiver Health (REACH) II intervention for use in 4 Area Agencies on Aging (AAAs). A secondary aim was to examine possible moderators of treatment outcome. Design and Methods: We used a quasi-experimental pre-post treatment design with no…

Burgio, Louis D.; Collins, Irene B.; Schmid, Bettina; Wharton, Tracy; McCallum, Debra; DeCoster, Jamie

2009-01-01

278

Photodegradation of dissolved organic matter in two contrasting reaches of a regulated river  

NASA Astrophysics Data System (ADS)

Dissolved organic matter (DOM) plays an important role in a variety of ecosystem processes. Photodegradation by UV radiation is an important mechanism for DOM transformations including changes in molecular size, molecular structure, UV-absorbance, the relative size of recalcitrant and labile pools, and regeneration of nutrient sources such as N and P. The upper Klamath River is located in southern Oregon and is considered an important resource for anadromous fish populations. The river is hypereutrophic and experiences multiple impairments including organic enrichment, low dissolved oxygen, nutrients, and temperature. The river is highly regulated by a series of six dams, which compartmentalize the river into a series of riverine and reservoir reaches. Reservoirs create alternative physical and chemical environments than rivers, and these differences have implications in shifting DOM composition and availability. Four of the six dams on the Klamath River are slated for removal in 2020. Therefore, predicting changes in ecosystem characteristics following dam removal requires understanding of current DOM dynamics within both riverine and reservoir reaches. The role of photodegradation on DOM composition within a riverine reach and a reservoir reach of the Klamath River was examined during late July 2010. The reaches were located in series, with the river reach being upstream of the reservoir reach. Initial mean DOC concentrations were 7.34 mg/L for river water, and 8.57 mg/L for reservoir water. Tedlar bags of filtered (0.1µm) river and reservoir water were incubated in situ at both river and reservoir locations. Samples were treated either with or without UV-exposure for a total of 1-3 days. All bags were incubated at 55 cm depth, equivalent to 70% light transmittance in the river reach and 30% light transmittance in the reservoir reach. Bags were removed in triplicate after a total of 1, 2, and 3 days. Samples were analyzed for potential bacterial growth using standard plating and colony count methods. Water was analyzed for dissolved organic carbon (DOC), nutrients, and pH, UV-absorbance properties, including specific UV absorbance (SUVA) and selected spectral slopes (275-295 nm slope and 350-400 nm slope), were used to investigate changes in DOM characteristics. Spectrofluorometric techniques were used to determine the fluorescence index (emission at wavelength 450 nm to 500 nm at an excitation wavelength of 370 nm) for investigation of source material and transformations. Preliminary results suggest little to no change in DOC or nutrient concentrations. However, shifts in SUVA, spectral slope, and fluorescence index were apparent in both reservoir and river samples incubated at both sites, with larger changes observed for river samples incubated within the river reach at 70% light transmittance. These results provide information on how photodegradation may affect DOM recycling and regeneration as an energy source within different compartmentalized reaches of the Klamath River. This information will subsequently aid in developing models for predicting DOM dynamics over larger spatial and temporal scales, including predictions and implications for conditions following dam removal.

Oliver, A. A.; Dahlgren, R. A.; Spencer, R. G.

2010-12-01

279

Estimation of Maximum Earthquakes in Northeast India  

NASA Astrophysics Data System (ADS)

We attempt to estimate possible maximum earthquakes in the northeast Indian region for four seismic source zones, namely EHZ, MBZ, EBZ, and SHZ, which encapsulates the various seismogenic structures of the region and also for combined source zones taken as a single seismic source regime. The latter case exhibits a high maximum earthquake estimate of MW 9.4 (±0.85) through Bayesian interpretation of frequency magnitude distribution with Gamma function implicating a moderate deviation from the standard Gutenberg Richter model at the higher magnitudes. However, tapering Gutenberg Richter models with corner magnitudes at MW 8.01, 8.7 and 9.1, respectively indicated maximum values corresponding to MW 8.4, 9.0, and 9.3. The former approach was applied to each of the source zones wherein the data are presented in parts according to the data completeness, thereof. EHZ, MBZ, EBZ and SHZ are seen with maximum earthquakes of MW 8.35 (±0.59), 8.79 (±0.31), 8.20 (±0.50), and 8.73 (±0.70), respectively. The maximum possible earthquakes estimated for each individual zone are seen to be lower than that estimated for the single regime. However, the pertaining return periods estimated for the combined zone are far less than those estimated for the demarcated ones.

Thingbaijam, K. K. S.; Nath, S. K.

2008-05-01

280

Maximum permissible voltage of YBCO coated conductors  

NASA Astrophysics Data System (ADS)

Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (Ic) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the Ic degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z.; Hong, Z.; Wang, D.; Zhou, H.; Shen, X.; Shen, C.

2014-06-01

281

Maximum magnitude earthquakes induced by fluid injection  

NASA Astrophysics Data System (ADS)

of numerous case histories of earthquake sequences induced by fluid injection at depth reveals that the maximum magnitude appears to be limited according to the total volume of fluid injected. Similarly, the maximum seismic moment seems to have an upper bound proportional to the total volume of injected fluid. Activities involving fluid injection include (1) hydraulic fracturing of shale formations or coal seams to extract gas and oil, (2) disposal of wastewater from these gas and oil activities by injection into deep aquifers, and (3) the development of enhanced geothermal systems by injecting water into hot, low-permeability rock. Of these three operations, wastewater disposal is observed to be associated with the largest earthquakes, with maximum magnitudes sometimes exceeding 5. To estimate the maximum earthquake that could be induced by a given fluid injection project, the rock mass is assumed to be fully saturated, brittle, to respond to injection with a sequence of earthquakes localized to the region weakened by the pore pressure increase of the injection operation and to have a Gutenberg-Richter magnitude distribution with a b value of 1. If these assumptions correctly describe the circumstances of the largest earthquake, then the maximum seismic moment is limited to the volume of injected liquid times the modulus of rigidity. Observations from the available case histories of earthquakes induced by fluid injection are consistent with this bound on seismic moment. In view of the uncertainties in this analysis, however, this should not be regarded as an absolute physical limit.

McGarr, A.

2014-02-01

282

Incidents when older homebound women tried to reach help quickly.  

PubMed

During a longitudinal study of the experience of reaching help quickly, 34 homebound women (ages 85 to 97) who lived alone reported 106 reach-help-quickly incidents (RHQIs). The purpose of this study was to expand knowledge about RHQIs and intentions relative to them and to compare those facets of experience for subscribers to a personal emergency response system (PERS) and non-subscribers. We used a descriptive phenomenological method to analyze interview data, discerning six types of RHQIs, including finding myself down right here, realizing that I might not be alright after falling and getting up on my own, and realizing that something I cannot explain is or could be wrong with me. Intentions were focused on self-help before help seeking. The overall phenomenon was Handling a Situation When I Am Alone at Home and Probably Need Help Quickly. Practitioners should explore intentions about handling specific types of RHQIs and offer appropriate anticipatory guidance. PMID:23205934

Porter, Eileen J; Markham, Melinda Stafford; Ganong, Lawrence H

2013-01-01

283

The challenge of reproductive and developmental toxicology under REACH  

Microsoft Academic Search

The European Union’s REACH regulation has explicit requirements for reproductive and developmental toxicity data on all substances manufactured in or imported into the European Union at ?10metric tons\\/year. Meeting the data requirements with whole-animal testing could result in the use of almost 22 million vertebrate animals for the registration of existing chemicals and cost up to several hundred thousand dollars

Anthony R. Scialli

2008-01-01

284

The Agreement: Agreement Reached in the Multi-party Negotiations  

NSDL National Science Digital Library

CELT, an archive of documents relating to Irish culture and history at University College, Cork, has made available the full text of the historic proposed peace treaty for Northern Ireland. Aimed at ending many years of sectarian violence, the treaty was reached after arduous and intense negotiations. The agreement is to be voted upon by the people of both Northern Ireland and the Irish Republic in late May, 1998.

1998-01-01

285

The personal space station: Bringing interaction within reach  

Microsoft Academic Search

Near-field virtual re- ality allows users to interact with virtual objects within arm's reach of the user. Environments for near-field VR are well suited for direct precise interaction by tak- ing advantage of the user's hand- eye co-ordination. We discuss the design and initial experience of a near-field virtual environment, the Personal Space Station (PSS). In this system, all interactive

Jurriaan D. Mulder; Robert van Liere

2002-01-01

286

Effective manipulation of virtual objects within arm's reach  

Microsoft Academic Search

We present a study that compares finger-based direct interaction to controller-based ray interaction in a CAVE as well as in headmounted displays. We focus on interaction tasks within reach of the users’ arms and hands and explore various feedback methods including visual, pressure-based tactile and vibro-tactile feedback. Furthermore, we enhanced a precise finger tracking device with a direct pinch-detection mechanism

Mathias Moehring; Bernd Froehlich

2011-01-01

287

Hard x-ray Zernike microscopy reaches 30 nm resolution.  

SciTech Connect

Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30?nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.

Chen, Y.; Chen, T.; Yi, J.; Chu, Y.; Lee, W.-K.; Wang, C.; Kempson, I.; Hwu, Y.; Gajdosik, V.; Margaritondo, G. (X-Ray Science Division); (Academia Sinica); (BNL); (National Tsing Hua Univ,); (National Taiwan Ocean Univ.); (Ecole Polytechnique Federale de Lausanne)

2011-03-30

288

Hard x-ray Zernike Microscopy Reaches 30 nm Resolution  

SciTech Connect

Since its invention in 1930, Zernike phase contrast has been a pillar in optical microscopy and more recently in x-ray microscopy, in particular for low-absorption-contrast biological specimens. We experimentally demonstrate that hard-x-ray Zernike microscopy now reaches a lateral resolution below 30 nm while strongly enhancing the contrast, thus opening many new research opportunities in biomedicine and materials science.

Chen, Y.T.; Chu, Y.; Chen, T-Y.; Yi, J.; Lee, W-K.; Wang, C-L.; Kempson, I. M.; Hwu, Y.; Gajdosik, V.; Margaritondo, G.

2011-03-30

289

Abundance, growth and food demand of the scyphomedusa Aurelia aurita in the western Wadden Sea  

NASA Astrophysics Data System (ADS)

Medusae of Aurelia aurita are found in the western Wadden Sea from the beginning of May till August with maximum numbers of 250 to 500 individuals per 10 3 m 3 during May-June. The existence of a continuous ebb surplus suggests an origin from polyps living in the inner parts of the estuary and a transport or migration of the released medusae towards the North Sea. Growth is fast; a bell size of 20 cm diameter is reached within 3 to 4 months. The species is important as a predator from May to July, reaching maximum carbon biomass values of 12 to 18 g C·10 3 m -3. Predation by A. aurita may affect the recruitment of one of its food sources, viz. fish larvae.

van der Veer, H. W.; Oorthuysen, W.

290

Dealing with Target Uncertainty in a Reaching Control Interface  

PubMed Central

Prosthetic devices need to be controlled by their users, typically using physiological signals. People tend to look at objects before reaching for them and we have shown that combining eye movements with other continuous physiological signal sources enhances control. This approach suffers when subjects also look at non-targets, a problem we addressed with a probabilistic mixture over targets where subject gaze information is used to identify target candidates. However, this approach would be ineffective if a user wanted to move towards targets that have not been foveated. Here we evaluated how the accuracy of prior target information influenced decoding accuracy, as the availability of neural control signals was varied. We also considered a mixture model where we assumed that the target may be foveated or, alternatively, that the target may not be foveated. We tested the accuracy of the models at decoding natural reaching data, and also in a closed-loop robot-assisted reaching task. The mixture model worked well in the face of high target uncertainty. Furthermore, errors due to inaccurate target information were reduced by including a generic model that relied on neural signals only.

Corbett, Elaine A.; Kording, Konrad P.; Perreault, Eric J.

2014-01-01

291

Hazard and risk assessment of teratogenic chemicals under REACH.  

PubMed

In 2007, a new European chemicals legislation was implemented: Regulation (EC) No. 1907/2006, also known as "REACH." It obliges companies to take the main responsibility for the valid information on the safe use of the chemicals they manufacture and/or place on the European market. So they must, for example, register their chemicals at the European Chemicals Agency (ECHA) and submit extensive substance-related registration dossiers containing information on the substances' intrinsic hazardous properties and documentation of their risk assessment. REACH regulates the registration and evaluation process as well as the authorization and restriction procedure. In addition, classification, labeling, and packaging of chemicals apply in accordance with Regulation (EC) No. 1272/2008 ("CLP Regulation"). It implements almost completely the provisions of the United Nations Globally Harmonised System of Classification and Labelling of Chemicals (UN GHS) into European legislation and will fully replace the Dangerous Substances Directive (67/548/EEC) and the Dangerous Preparations Directive (1999/45/EC) by 2015. According to both the old and the new classification system, teratogenic chemicals are classified as developmental toxicants, with developmental toxicity falling within the hazard class of reproductive toxicity. REACH as well as the CLP Regulation provide several procedures in which reproductive toxicants take a special position because their harmful effects are considered particularly serious. Teratogenic substances are not explicitly named by these legal texts but, as they constitute as developmental toxicants a hazard differentiation of reproductive toxicity, they are implicitly always included by the provisions. PMID:23138924

Prutner, Wiebke

2013-01-01

292

Functional Corticomuscular Connection During Reaching Is Weakened Following Stroke  

PubMed Central

Objective To investigate the functional connection between motor cortex and muscles, we measured Electroencephalogram-Electromyogram (EEG-EMG) coherence of stroke patients and controls. Methods Eight healthy controls and 21 patients with shoulder and elbow coordination deficits were enrolled. All subjects performed a reaching task involving shoulder flexion and elbow extension. EMG of the anterior deltoid (AD) and brachii muscles (BB, TB) and 64-channel scalp EEG were recorded during the task. Time-frequency coherence was calculated using the bivariate autoregressive model. Results Stroke patients had significantly lower corticomuscular coherence compared with healthy controls for the AD and BB muscles at both the beta (20-30 Hz) and lower gamma (30-40 Hz) bands during the movement. BH procedure (FDR) identified a reduced corticomuscular coherence for stroke patients in 11 of 15 scalp area-muscle combinations. There was no statistically significant difference between stroke patients and control subjects according to coherence in other frequency bands. Conclusion Poorly recovered stroke survivors with persistent upper-limb motor deficits exhibited significantly lower gamma-band corticomuscular coherence in performing a reaching task. Significance The study suggests poor brain-muscle communication or poor integration of the EEG and EMG signals in higher frequency band during reaching task may reflect an underlying mechanism producing movement deficits post stroke.

Fang, Yin; Daly, Janis J; Sun, Jiayang; Hvorat, Ken; Fredrickson, Eric; Pundik, Svetlana; Sahgal, Vinod; Yue, Guang H.

2009-01-01

293

Distractor interference during a choice limb reaching task.  

PubMed

According to action-centered models of attention, the patterns of distractor interference that emerge in selective reaching tasks are related to the time and effort required to resolve a race for activation between competing target and non-target response producing processes. Previous studies have only used unimanual aiming tasks and, as such, only examined the effects of competition that occurs within a limb. The results of studies using unimanual aiming movements often reveal an "ipsilateral effect"--distractors on the same side of space as the effector cause greater interference than distractors on the opposite side of space. The cost of the competition when response selection is between the limbs has yet to be addressed. Participants in the present study executed reaching movements to 1 of 4 (2 left, 2 right) possible target locations with and without a distractor. Participants made ipsilateral reaches (left hand to left targets, right hand to right targets). In contrast to studies using unimanual aiming movements, a "contralateral effect" was observed; distractors affording responses for the other hand (in contralateral space) caused more interference than distractors affording responses for the same hand. The findings from the present research demonstrate that when certain portions of response planning must be resolved prior to response initiation, distractors that code for that dimension cause the greatest interference. PMID:24465813

Ray, Matthew; Weeks, Daniel; Welsh, Timothy N

2014-01-01

294

Gigantic Maximum of Nanoscale Noncontact Friction  

NASA Astrophysics Data System (ADS)

We report measurements of noncontact friction between surfaces of NbSe2 and SrTiO3 and a sharp Pt-Ir tip that is oscillated laterally by a quartz tuning fork cantilever. At 4.2 K, the friction coefficients on both the metallic and insulating materials show a giant maximum at the tip-surface distance of several nanometers. The maximum is strongly correlated with an increase in the spring constant of the cantilever. These features can be understood phenomenologically by a distance-dependent relaxation mechanism with distributed time scales.

Saitoh, Kohta; Hayashi, Kenichi; Shibayama, Yoshiyuki; Shirahama, Keiya

2010-12-01

295

Estimating Maximum Discharge of Geothermal Wells  

SciTech Connect

We cannot tell how 'good' a well is unless we can estimate the maximum flow possible under such ideal conditions as complete permeability a t the production horizon and boiling point throughout the depth of the reservoir. Calculated Lip pressures for vertical wide-open discharge under these conditions are surprisingly independent of the kind of fluid tapped by the well, whether dry saturated steam or saturated hot water. The status of an actual well can be established by comparing the measured Lip pressure with the calculated theoretical maximum. Discharges are simply determined from the values of Lip pressure and supply fluid enthalpy.

James, Russell

1980-12-16

296

Density estimation by maximum quantum entropy  

SciTech Connect

A new Bayesian method for non-parametric density estimation is proposed, based on a mathematical analogy to quantum statistical physics. The mathematical procedure is related to maximum entropy methods for inverse problems and image reconstruction. The information divergence enforces global smoothing toward default models, convexity, positivity, extensivity and normalization. The novel feature is the replacement of classical entropy by quantum entropy, so that local smoothing is enforced by constraints on differential operators. The linear response of the estimate is proportional to the covariance. The hyperparameters are estimated by type-II maximum likelihood (evidence). The method is demonstrated on textbook data sets.

Silver, R.N.; Wallstrom, T.; Martz, H.F.

1993-11-01

297

Maximum predictive power and the superposition principle  

NASA Technical Reports Server (NTRS)

In quantum physics the direct observables are probabilities of events. We ask how observed probabilities must be combined to achieve what we call maximum predictive power. According to this concept the accuracy of a prediction must only depend on the number of runs whose data serve as input for the prediction. We transform each probability to an associated variable whose uncertainty interval depends only on the amount of data and strictly decreases with it. We find that for a probability which is a function of two other probabilities maximum predictive power is achieved when linearly summing their associated variables and transforming back to a probability. This recovers the quantum mechanical superposition principle.

Summhammer, Johann

1994-01-01

298

Aging, Maturation and Growth of Sauropodomorph Dinosaurs as Deduced from Growth Curves Using Long Bone Histological Data: An Assessment of Methodological Constraints and Solutions  

PubMed Central

Information on aging, maturation, and growth is important for understanding life histories of organisms. In extinct dinosaurs, such information can be derived from the histological growth record preserved in the mid-shaft cortex of long bones. Here, we construct growth models to estimate ages at death, ages at sexual maturity, ages at which individuals were fully-grown, and maximum growth rates from the growth record preserved in long bones of six sauropod dinosaur individuals (one indeterminate mamenchisaurid, two Apatosaurus sp., two indeterminate diplodocids, and one Camarasaurus sp.) and one basal sauropodomorph dinosaur individual (Plateosaurus engelhardti). Using these estimates, we establish allometries between body mass and each of these traits and compare these to extant taxa. Growth models considered for each dinosaur individual were the von Bertalanffy model, the Gompertz model, and the logistic model (LGM), all of which have inherently fixed inflection points, and the Chapman-Richards model in which the point is not fixed. We use the arithmetic mean of the age at the inflection point and of the age at which 90% of asymptotic mass is reached to assess respectively the age at sexual maturity or the age at onset of reproduction, because unambiguous indicators of maturity in Sauropodomorpha are lacking. According to an AIC-based model selection process, the LGM was the best model for our sauropodomorph sample. Allometries established are consistent with literature data on other Sauropodomorpha. All Sauropodomorpha reached full size within a time span similar to scaled-up modern mammalian megaherbivores and had similar maximum growth rates to scaled-up modern megaherbivores and ratites, but growth rates of Sauropodomorpha were lower than of an average mammal. Sauropodomorph ages at death probably were lower than that of average scaled-up ratites and megaherbivores. Sauropodomorpha were older at maturation than scaled-up ratites and average mammals, but younger than scaled-up megaherbivores.

Griebeler, Eva Maria; Klein, Nicole; Sander, P. Martin

2013-01-01

299

Last Glacial Maximum age for the northwest Laurentide maximum from the Eagle River spillway and delta complex, northern Yukon  

NASA Astrophysics Data System (ADS)

The Eagle River spillway and braid delta complex provide a record of the maximum extent of the northwest Laurentide Ice Sheet and diversion of meltwater from Bonnet Plume Basin into the interior basins of non-glaciated northern Yukon. Development of the spillway can be characterized in three distinct zones based on the distribution of erosion and deposition along each reach: erosion-dominated channel initiation and incision; followed by channelization and coarse clastic deposition along channel margins and into tributary valleys; and lastly, fine-grained deltaic and lacustrine sedimentation in the lower channel reach. Deltaic sedimentation within the spillway is crudely-coarsening upward from alternating beds of massive clay and silt to ripple-cross-bedded sand. All sediments occur in rapidly-aggrading forms with no evidence for a significant hiatus in deposition. Radiocarbon ages on woody plant macrofossils and spruce needles are non-finite, while radiocarbon ages on macrofossils from herbaceous plant taxa and insects with 'steppe-tundra' ecological affinity from the upper part of the delta range from 15?840 ± 90 to 21?600 ± 1300 14C yr BP. These ages, coupled with the rapidly-aggrading nature of the delta sediments and landform, suggest an age of ca 15-16?000 14C yr BP. Non-finite and mixed ages underscore the significant problem of reworked, well-preserved macrofossils in Arctic environments and the need for careful selection of both fragile and ecologically-representative macrofossils to establish reliable chronologies.

Kennedy, K. E.; Froese, D. G.; Zazula, G. D.; Lauriol, B.

2010-05-01

300

Medium for isolation and growth of bacteria associated with plum leaf scald and phony peach diseases.  

PubMed

Rickettsia-like bacteria associated with plum leaf scald and phony peach diseases were isolated from diseased but not from healthy tissues and cultured on charcoal-yeast extract medium (BCYE) buffered with ACES (2-[(2-amino-2-oxoethyl) amino]-ethanesulfonic acid). Optimum conditions for isolation and growth on BCYE medium were pH 6.5 to 6.9 at 20 and 25 degrees C under normal atmosphere. Growth of primary colonies and first-passage subcultures was restricted, and colonies reached a maximum diameter of 0.6 mm in 60 days. After 12 passages, subcultures reached maximum growth in 21 days. The rickettsia-like bacteria from BCYE cultures were gram negative, serologically the same as those present in diseased peach and plum, and composed of rod-shaped cells measuring 0.35 by 5 mum (average diameter and maximum length) in a matrix of filamentous strands of similar width but of variable length. PMID:16345835

Wells, J M; Raju, B C; Nyland, G; Lowe, S K

1981-08-01

301

24 CFR 941.306 - Maximum project cost.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Maximum project cost. 941.306 Section 941.306 Housing...Application and Proposal § 941.306 Maximum project cost. (a) Calculation of maximum project cost. The maximum project cost...

2010-04-01

302

24 CFR 941.306 - Maximum project cost.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Maximum project cost. 941.306 Section 941.306 Housing...Application and Proposal § 941.306 Maximum project cost. (a) Calculation of maximum project cost. The maximum project cost...

2012-04-01

303

24 CFR 941.306 - Maximum project cost.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Maximum project cost. 941.306 Section 941.306 Housing...Application and Proposal § 941.306 Maximum project cost. (a) Calculation of maximum project cost. The maximum project cost...

2011-04-01

304

40 CFR 94.107 - Determination of maximum test speed.  

Code of Federal Regulations, 2010 CFR

...false Determination of maximum test speed. 94.107 Section 94.107 Protection...107 Determination of maximum test speed. (a) Overview. This section specifies how to determine maximum test speed from a lug curve. This maximum...

2009-07-01

305

40 CFR 94.107 - Determination of maximum test speed.  

Code of Federal Regulations, 2013 CFR

...false Determination of maximum test speed. 94.107 Section 94.107 Protection...107 Determination of maximum test speed. (a) Overview. This section specifies how to determine maximum test speed from a lug curve. This maximum...

2013-07-01

306

40 CFR 94.107 - Determination of maximum test speed.  

Code of Federal Regulations, 2010 CFR

...false Determination of maximum test speed. 94.107 Section 94.107 Protection...107 Determination of maximum test speed. (a) Overview. This section specifies how to determine maximum test speed from a lug curve. This maximum...

2010-07-01

307

40 CFR 141.13 - Maximum contaminant levels for turbidity.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Maximum contaminant levels for turbidity. 141.13 Section 141.13...DRINKING WATER REGULATIONS Maximum Contaminant Levels § 141.13 Maximum contaminant levels for turbidity. The maximum...

2013-07-01

308

40 CFR 141.65 - Maximum residual disinfectant levels.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Maximum residual disinfectant levels. 141.65 Section 141.65 Protection...Drinking Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels § 141.65 Maximum residual...

2013-07-01

309

Maximum Fillet Stresses in Breech Ring.  

National Technical Information Service (NTIS)

The effect of fillet geometry and wall thickness on maximum fillet stresses was investigated in the 105mm M137 Howitzer breech ring. The NASTRAN finite element analysis of three fillet geometries and two wall thicknesses shows that an elliptical fillet is...

Y. F. Cheng

1972-01-01

310

Maximum versus meaningful discrimination in scale response  

Microsoft Academic Search

This paper argues for the use of the number of response categories that are meaningful to respondents as a criterion in designing attribute rating scales in marketing in contrast to a focus in past research on using scales to maximize the discrimination elicited from respondents. Whereas scales eliciting a maximum level of discrimination may be more reliable than scales eliciting

Madhubalan Viswanathan; Seymour Sudman; Michael Johnson

2004-01-01

311

Maximum Entropy Estimation for Survey sampling  

Microsoft Academic Search

Calibration methods have been widely studied in survey sampling over the last decades. Viewing calibration as an inverse problem, we extend the calibration technique by using a maximum entropy method. Finding the optimal weights is achieved by considering random weights and looking for a discrete distribution which maximizes an entropy under the calibration constraint. This method points a new frame

Fabrice Gamboa; Jean-Michel Loubes; Paul Rochet

2009-01-01

312

Maximum Sunspot Numbers and Active Days  

NASA Astrophysics Data System (ADS)

Parameters associated with solar minimum have been studied to relate them to solar activity at solar maximum so that one could possibly predict behaviors of an upcoming solar cycle. The number of active days has been known as a reliable indicator of solar activity around solar minimum. Active days are days with sunspots reported on the solar disk. In this work, we have explored the relationship between the sunspot numbers at solar maximum and the characteristics of the monthly number of active days. Specifically, we have statistically examined how the maximum monthly sunspot number of a given solar cycle is correlated with the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days for the corresponding solar cycle. We have calculated the linear correlation coefficient r and the Spearman rank-order correlation coefficient rs for data sets prepared under various conditions. Even though marginal correlations are found, they turn out to be insufficiently significant (r ~ 0.3). Nonetheless, we have confirmed that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is less steep when solar cycles belonging to the "Modern Maximum" are considered compared with rests of solar cycles. We conclude, therefore, that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is indeed dependent on the solar activity at its maxima, but that this simple relationship should be insufficient as a valid method to predict the following solar activity amplitude.

Chang, Heon-Young

2013-09-01

313

Maximum output of an OTEC power plant  

Microsoft Academic Search

This paper theoretically investigates the effects of the temperature and flowrate of cold seawater on the net output of an OTEC plant. Parameters of pipe length, pipe diameter, seawater depth, and the flowrate of seawater are considered. It shows that a maximum output of the net work exists at a certain flowrate of cooling seawater. The output work is higher

Rong-Hua Yeh; Tar-Zen Su; Min-Shong Yang

2005-01-01

314

Analysis of Photovoltaic Maximum Power Point Trackers  

NASA Astrophysics Data System (ADS)

The photovoltaic generator exhibits a non-linear i-v characteristic and its maximum power point (MPP) varies with solar insolation. An intermediate switch-mode dc-dc converter is required to extract maximum power from the photovoltaic array. In this paper buck, boost and buck-boost topologies are considered and a detailed mathematical analysis, both for continuous and discontinuous inductor current operation, is given for MPP operation. The conditions on the connected load values and duty ratio are derived for achieving the satisfactory maximum power point operation. Further, it is shown that certain load values, falling out of the optimal range, will drive the operating point away from the true maximum power point. Detailed comparison of various topologies for MPPT is given. Selection of the converter topology for a given loading is discussed. Detailed discussion on circuit-oriented model development is given and then MPPT effectiveness of various converter systems is verified through simulations. Proposed theory and analysis is validated through experimental investigations.

Veerachary, Mummadi

315

Heliospheric Magnetic Field Structure At Solar Maximum  

Microsoft Academic Search

The evolution of the heliospheric magnetic field (HMF) from the relative simplicity at solar minimum has been charted by the Ulysses spacecraft through the ascending phase of the solar cycle through the recent maximum activity epoch. The changes that occurred in solar and coronal magnetic fields from 1997 to 2001 are reflected in a com- plex way in the evolution

A. Balogh; E. J. Smith; R. J. Forsyth; G. H. Jones; D. J. McComas

2002-01-01

316

Mammographic image restoration using maximum entropy deconvolution  

Microsoft Academic Search

An image restoration approach based on a Bayesian maximum entropy method (MEM) has been applied to a radiological image deconvolution problem, that of reduction of geometric blurring in magnification mammography. The aim of the work is to demonstrate an improvement in image spatial resolution in realistic noisy radiological images with no associated penalty in terms of reduction in the signal-to-noise

A. Jannetta; J. C. Jackson; C. J. Kotre; I. P. Birch; K. J. Robson; R. Padgett

2004-01-01

317

Predicting maximum lake depth from surrounding topography.  

PubMed

Information about lake morphometry (e.g., depth, volume, size, etc.) aids understanding of the physical and ecological dynamics of lakes, yet is often not readily available. The data needed to calculate measures of lake morphometry, particularly lake depth, are usually collected on a lake-by-lake basis and are difficult to obtain across broad regions. To span the gap between studies of individual lakes where detailed data exist and regional studies where access to useful data on lake depth is unavailable, we developed a method to predict maximum lake depth from the slope of the topography surrounding a lake. We use the National Elevation Dataset and the National Hydrography Dataset - Plus to estimate the percent slope of surrounding lakes and use this information to predict maximum lake depth. We also use field measured maximum lake depths from the US EPA's National Lakes Assessment to empirically adjust and cross-validate our predictions. We were able to predict maximum depth for ?28,000 lakes in the Northeastern United States with an average cross-validated RMSE of 5.95 m and 5.09 m and average correlation of 0.82 and 0.69 for Hydrological Unit Code Regions 01 and 02, respectively. The depth predictions and the scripts are openly available as supplements to this manuscript. PMID:21984945

Hollister, Jeffrey W; Milstead, W Bryan; Urrutia, M Andrea

2011-01-01

318

Multiple target tracking using maximum likelihood principle  

Microsoft Academic Search

Proposes a method (tracking algorithm (TAL)) based on the maximum likelihood (ML) principle for multiple target tracking in near-field using outputs from a large uniform linear array of passive sensors. The targets are assumed to be narrowband signals and modeled as sample functions of a Gaussian stochastic process. The phase delays of these signals are expressed as functions of both

A. Satish; Rangasami L. Kashyap

1995-01-01

319

Entropy Maximum Principle and Relaxation Phenomena.  

National Technical Information Service (NTIS)

A Shannon (epoch) entropy is defined in terms of an integral over the full temporal epoch of relaxation. A maximum entropy principle yields a linear exponential as a fundamental form for relaxation to equilibrium. It is observed that the time scale of mea...

A. K. Rajagopal, S. Teitler, K. L. Ngai

1984-01-01

320

Maximum entropy image restoration in astronomy  

Microsoft Academic Search

The theoretical basis and applications of the Maximum Entropy Method of inference for obtaining the most probable nonnegative image consistent with astronomical data are detailed. The generalized image restoration problem is reviewed, noting the effects of atmospheric blurring and the practice of representing images as a Fourier series. The problem is encountered in both single aperture and synthesis observations, and

Ramesh Narayan; Rajaram Nityananda

1986-01-01

321

Menu Plans: Maximum Nutrition for Minimum Cost.  

ERIC Educational Resources Information Center

Suggests that menu planning is the key to getting maximum nutrition in day care meals and snacks for minimum cost. Explores United States Department of Agriculture food pyramid guidelines for children and tips for planning menus and grocery shopping. Includes suggested meal patterns and portion sizes. (HTH)

Texas Child Care, 1995

1995-01-01

322

Climate Change Impacts on Probable Maximum Precipitation  

NASA Astrophysics Data System (ADS)

The estimation of the potential impacts of anthropogenic forcing of the climate system on extreme weather events relies heavily on the direct output of global and regional climate models, combined perhaps with extreme value statistical techniques. In this study, we use these tools along with physical and theoretical considerations to examine the potential impacts on Probable Maximum Precipitation estimates. Probable Maximum Precipitation (PMP) is the theoretically greatest depth of precipitation for a given duration that is physically possible over a particular drainage basin at a particular time of year. PMP values are used in the design of long-lived structures with lifetimes of many decades, such as dams. Climate change is an unavoidable consideration on those time scales. Many studies have documented an upward temporal trend in the frequency and intensity of extreme precipitation events. As the globe warms in response to increasing greenhouse gas concentrations, there is the potential for further changes in precipitation extremes. There are reasons why warming could lead to increased PMP values. One, the Clausius-Clapeyron relationship indicates that the saturation water vapor pressure increases with temperature; thus, precipitation-producing systems could have more "fuel" to precipitate. Two, warming may lead to an increase in the length of the convective season, when most of the extreme precipitation events occur. The methodology for estimation of PMP values has changed little over the last 30-40 years. The basic approach is to consider the factors that contribute to heavy precipitation and then consider the potential precipitation rates if all of those factors were simultaneously maximized. Convergence and vertical motion is one factor. Past work has assumed that there no empirical or satisfactory theoretical basis for assigning maximum values to this factor. The approach has been to use observed rainfall in notable storms as an indirect measure of maximum convergence and vertical motion. Notable storms are chosen to indicate the likely occurrence of near-maximum values. A second central factor is moisture availability. Observational data are used to determine maximum levels of moisture availability. Where topographic effects are important, wind maximization is a third factor. We are examining these factors in present-day and future simulations from global and regional climate models. Initial results strongly indicate the possibility for large future increases in maximum moisture, by about the same amount as increases in mean moisture content. This would lead directly to substantial increases in PMP values. Given the potential catastrophic consequences of dam failure, these findings should be considered carefully in future design activities.

Kunkel, K.; Easterling, D. R.

2011-12-01

323

Hemispheric asymmetries for kinematic and positional aspects of reaching.  

PubMed

Kinematic analyses of reaching have suggested that the left hemisphere is dominant for controlling the open loop component of the movement, which is more dependent on motor programmes; and the right hemisphere is dominant for controlling the closed loop component, which is more dependent on sensory feedback. This open and closed loop hypothesis of hemispheric asymmetry would also predict that advance planning should be dependent on the left hemisphere, and on-line response modification, which defines closed loop processes, should be dependent on the right hemisphere. Using kinematic analyses of reaching in patients with left or right hemisphere damage (LHD or RHD), we examined the ability: (i) to plan reaching movements in advance by examining changes in reaction time (RT) when response amplitude and visual feedback were cued prior to the response; and (ii) to modify the response during implementation when target location changed at the RT. Performance was compared between the stroke groups, using the ipsilesional arm, and age-matched control groups using their right (RNC) or left (LNC) arm. Aiming movements to a target that moved once or twice, with the second step occurring at the RT, were performed with or without visual feedback of hand position. There were no deficits in advance planning in either stroke group, as evidenced by comparable group changes in RT with changes in amplitude and visual feedback. Response modification deficits were seen for the LHD group in secondary velocity only. In addition, LHD produced slower initial peak velocity with prolongation of the deceleration phase and faster secondary peak velocities, and the RHD group produced deficits in final error only. These differences are more consistent with the dynamic dominance hypothesis, which links left hemisphere specialization to movement trajectory control and right hemisphere specialization to position control, rather than to global deficits in open and closed loop processing. PMID:15033898

Haaland, Kathleen Y; Prestopnik, Jillian L; Knight, Robert T; Lee, Roland R

2004-05-01

324

20 CFR 30.911 - Does maximum medical improvement always have to be reached for an impairment to be included in...  

Code of Federal Regulations, 2013 CFR

... Section 30.911 Employees' Benefits OFFICE OF WORKERS' COMPENSATION PROGRAMS, DEPARTMENT OF LABOR ENERGY EMPLOYEES OCCUPATIONAL ILLNESS COMPENSATION...OF 2000, AS AMENDED Impairment Benefits Under Part E of EEOICPA...

2013-04-01

325

The reach of INO for atmospheric neutrino oscillation parameters  

NASA Astrophysics Data System (ADS)

The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL@INO) for the study of atmospheric neutrinos. Using the detector resolutions and efficiencies obtained by the INO collaboration from a full-detector GEANT4-based simulation, we determine the reach of this experiment for the measurement of the atmospheric neutrino mixing parameters ( {sin^2 {?_{23 }}and| {\\varDelta m_{32}^2} |} ) . We also explore the sensitivity of this experiment to the octant of ? 23, and its deviation from maximal mixing.

Thakore, Tarak; Ghosh, Anushree; Choubey, Sandhya; Dighe, Amol

2013-05-01

326

[Human appropriation of net primary production in the middle reach of Heihe River basin].  

PubMed

Based on Miami model, this paper calculated the human appropriation of net primary production (HANPP) in the middle reach of Heihe River basin, discussed the relations between the HANPP and ecosystem diversity, and compared the values of HANPP and ecological footprint (EF) in sustainability assessment. The results showed that the increase of HANPP decreased the ecosystem diversity, and the current average HANPP in study area was 38.61%. The HANPP in Suzhou and Ganzhou districts already exceeded the potential maximum productivity. Considering the climate change and the development of social-economics, the ecosystems in study area would face more stress in the coming 40 years. Comparing with EF, HANPP was more available for the assessment of sustainability in the sight of ecosystem function change. PMID:18593049

Long, Ai-hua; Wang, Hao; Cheng, Guo-dong; Yu, Fu-liang

2008-04-01

327

Information models of software productivity - Limits on productivity growth  

NASA Technical Reports Server (NTRS)

Research into generalized information-metric models of software process productivity establishes quantifiable behavior and theoretical bounds. The models establish a fundamental mathematical relationship between software productivity and the human capacity for information traffic, the software product yield (system size), information efficiency, and tool and process efficiencies. An upper bound is derived that quantifies average software productivity and the maximum rate at which it may grow. This bound reveals that ultimately, when tools, methodologies, and automated assistants have reached their maximum effective state, further improvement in productivity can only be achieved through increasing software reuse. The reuse advantage is shown not to increase faster than logarithmically in the number of reusable features available. The reuse bound is further shown to be somewhat dependent on the reuse policy: a general 'reuse everything' policy can lead to a somewhat slower productivity growth than a specialized reuse policy.

Tausworthe, Robert C.

1992-01-01

328

Shifts in food quality for herbivorous consumer growth: multiple golden means in the life history.  

PubMed

Consumer growth can be affected by imbalances between the nutrient content of the consumer and its food resource. Although ontogenetic-driven changes in animal composition are well documented, their potential consequences for the organism's sensitivity to food quality constraints have remained elusive. Here we show that the potential growth response of the copepod Mixodiaptomus laciniatus (as %RNA and RNA:DNA ratio) to the natural gradient of seston carbon (C) : nutrient ratio is unimodal and stage specific. Solution of the equation given by the first derivative function provided the optimum C : nutrient ratio for maximum stage-specific growth, which increased during ontogeny. The peakedness of the function indicated that animal vulnerability to suboptimal food quality decreased as juveniles reached adulthood. Consistent with these results, a field experiment demonstrated that potential consumer growth responded to variations in seston C: phosphorus ratio, and that early life stages were particularly vulnerable to suboptimal food quality. PMID:25000759

Bullejos, Francisco José; Carrillo, Presentación; Gorokhova, Elena; Medina-Sánchez, Juan Manuel; Balseiro, Esteban Gabriel; Villar-Argaiz, Manuel

2014-05-01

329

Growth of Byssochlamys Nivea in Pineapple Juice Under the Effect of Water Activity and Ascospore Age  

PubMed Central

The study of thermal resistant mould, including Byssochlamys nivea, is of extreme importance since it has been associated with fruit and fruit products. The aim of this work is to analyze the influence of water activity (aw) and ascospore age (I) on the growth of Byssochlamys nivea in pineapple juice. Mold growth was carried out under different conditions of water activity (aw) (0.99, 0.96, 0.95, 0.93, 0.90) and ascospore age (I) (30, 51, 60, 69, 90 days). Growth parameters as length of adaptation phase (?), maximum specific growth rate (µmax) and maximum diameter reached by the colony (A) were obtained through the fit of the Modified Gompertz model to experimental data (measuring radial colony diameter). Statistica 6.0 was used for statistical analyses (significance level ? = 0.05). The results obtained clearly showed that water activity is statistically significant and that it influences all growth parameters, while ascospore age does not have any statistically significant influence on growth parameters. Also, these data showed that by increasing aw from 0.90 to 0.99, the ? value substantially decreased, while µmax and A values rose. The data contributed for the understanding of the behavior of B. nivea in pineapple juice. Therefore, it provided mathematical models that can well predict growth parameters, also helping on microbiological control and products’ shelf life determination.

Zimmermann, M.; Miorelli, S.; Massaguer, P.R.; Aragao, G.M.F.

2011-01-01

330

Tactile gating in a reaching and grasping task.  

PubMed

Abstract A multitude of events bombard our sensory systems at every moment of our lives. Thus, it is important for the sensory cortex to gate unimportant events. Tactile suppression is a well-known phenomenon defined as a reduced ability to detect tactile events on the skin before and during movement. Previous experiments found detection rates decrease just prior to and during finger abduction, and decrease according to the proximity of the moving effector. This study examined how tactile detection changes during a reach to grasp. Fourteen human participants used their right hand to reach and grasp a cylinder. Tactors were attached to the index finger, the fifth digit, and the forearm of both the right and left arm and vibrated at various epochs relative to a "go" tone. Results showed that detection rates at the forearm decreased before movement onset; whereas at the right index finger, right fifth digit and at the left index finger, left fifth digit, and forearm sites did not decrease like in the right forearm. These results indicate that the task affects gating dynamics in a temporally- and contextually dependent manner and implies that feed-forward motor planning processes can modify sensory signals. PMID:24760521

Colino, Francisco L; Buckingham, Gavin; Cheng, Darian T; van Donkelaar, Paul; Binsted, Gordon

2014-01-01

331

Integrated testing strategy (ITS) for bioaccumulation assessment under REACH.  

PubMed

REACH (registration, evaluation, authorisation and restriction of chemicals) regulation requires that all the chemicals produced or imported in Europe above 1 tonne/year are registered. To register a chemical, physicochemical, toxicological and ecotoxicological information needs to be reported in a dossier. REACH promotes the use of alternative methods to replace, refine and reduce the use of animal (eco)toxicity testing. Within the EU OSIRIS project, integrated testing strategies (ITSs) have been developed for the rational use of non-animal testing approaches in chemical hazard assessment. Here we present an ITS for evaluating the bioaccumulation potential of organic chemicals. The scheme includes the use of all available data (also the non-optimal ones), waiving schemes, analysis of physicochemical properties related to the end point and alternative methods (both in silico and in vitro). In vivo methods are used only as last resort. Using the ITS, in vivo testing could be waived for about 67% of the examined compounds, but bioaccumulation potential could be estimated on the basis of non-animal methods. The presented ITS is freely available through a web tool. PMID:24806447

Lombardo, Anna; Roncaglioni, Alessandra; Benfentati, Emilio; Nendza, Monika; Segner, Helmut; Fernández, Alberto; Kühne, Ralph; Franco, Antonio; Pauné, Eduard; Schüürmann, Gerrit

2014-08-01

332

Iron deficiency anemia in infancy and reach and grasp development  

PubMed Central

This study assessed 9 kinematic characteristics of infants’ reach and grasp to test the hypothesis that iron deficiency anemia (IDA) delays upper extremity motor development. Reach and grasp movements, recorded with a 3D-motion capture system, were compared in 9- to 10-month-old infants (4 IDA vs. 5 iron-sufficient [IS]). Based on normative motor development data available for 6 characteristics, the results indicated poorer upper extremity control in IDA infants: 2 characteristics showed statistically significant group differences despite small n, and the other 4 had strong indications for such results (effect sizes [Cohen's d] > 1.2). The remaining 3 measures, for which normative studies do not show developmental changes in this age period, showed significant or moderate-to- large effect differences. Poorer upper-extremity control in IDA infants in the short-term in this study and in the long-term despite iron therapy in other studies suggests that a motor intervention may be warranted when IDA is detected in infancy.

Shafir, Tal; Angulo-Barroso, Rosa; Su, Jing; Jacobson, Sandra W.; Lozoff, Betsy

2009-01-01

333

Ricin A chain reaches the endoplasmic reticulum after endocytosis  

SciTech Connect

Ricin is a potent ribosome inactivating protein and now has been widely used for synthesis of immunotoxins. To target ribosome in the mammalian cytosol, ricin must firstly retrograde transport from the endomembrane system to reach the endoplasmic reticulum (ER) where the ricin A chain (RTA) is recognized by ER components that facilitate its membrane translocation to the cytosol. In the study, the fusion gene of enhanced green fluorescent protein (EGFP)-RTA was expressed with the pET-28a (+) system in Escherichia coli under the control of a T7 promoter. The fusion protein showed a green fluorescence. The recombinant protein can be purified by metal chelated affinity chromatography on a column of NTA. The rabbit anti-GFP antibody can recognize the fusion protein of EGFP-RTA just like the EGFP protein. The cytotoxicity of EGFP-RTA and RTA was evaluated by the MTT assay in HeLa and HEP-G2 cells following fluid-phase endocytosis. The fusion protein had a similar cytotoxicity of RTA. After endocytosis, the subcellular location of the fusion protein can be observed with the laser scanning confocal microscopy and the immuno-gold labeling Electro Microscopy. This study provided important evidence by a visualized way to prove that RTA does reach the endoplasmic reticulum.

Liu Qiong [Department of Biochemistry and Molecular Biology, Zhejiang University Medical School, Hangzhou 310006 (China); Department of Biochemistry and Molecular Biology, Ningbo University Medical School, Ningbo 315211 (China); Zhan Jinbiao [Department of Biochemistry and Molecular Biology, Zhejiang University Medical School, Hangzhou 310006 (China) and Second Affiliated Hospital (Cancer Institute), Zhejiang University Medical School, Hangzhou 310006 (China)]. E-mail: jzhan2k@zju.edu.cn; Chen Xinhong [Department of Biochemistry and Molecular Biology, Yangzhou University Medical School, Yangzhou 225001 (China); Zheng Shu [Second Affiliated Hospital (Cancer Institute), Zhejiang University Medical School, Hangzhou 310006 (China)

2006-05-12

334

Tactile gating in a reaching and grasping task  

PubMed Central

Abstract A multitude of events bombard our sensory systems at every moment of our lives. Thus, it is important for the sensory cortex to gate unimportant events. Tactile suppression is a well?known phenomenon defined as a reduced ability to detect tactile events on the skin before and during movement. Previous experiments found detection rates decrease just prior to and during finger abduction, and decrease according to the proximity of the moving effector. This study examined how tactile detection changes during a reach to grasp. Fourteen human participants used their right hand to reach and grasp a cylinder. Tactors were attached to the index finger, the fifth digit, and the forearm of both the right and left arm and vibrated at various epochs relative to a “go” tone. Results showed that detection rates at the forearm decreased before movement onset; whereas at the right index finger, right fifth digit and at the left index finger, left fifth digit, and forearm sites did not decrease like in the right forearm. These results indicate that the task affects gating dynamics in a temporally? and contextually dependent manner and implies that feed?forward motor planning processes can modify sensory signals.

Colino, Francisco L.; Buckingham, Gavin; Cheng, Darian T.; van Donkelaar, Paul; Binsted, Gordon

2014-01-01

335

Optically trapped mirror for reaching the standard quantum limit  

NASA Astrophysics Data System (ADS)

The preparation of a mechanical oscillator driven by quantum back-action is a fundamental requirement to reach the standard quantum limit (SQL) for force measurement, in optomechanical systems. However, thermal fluctuating force generally dominates a disturbance on the oscillator. In the macroscopic scale, an optical linear cavity including a suspended mirror has been used for the weak force measurement, such as gravitational-wave detectors. This configuration has the advantages of reducing the dissipation of the pendulum (i.e., suspension thermal noise) due to a gravitational dilution by using a thin wire, and of increasing the circulating laser power. However, the use of the thin wire is weak for an optical torsional anti-spring effect in the cavity, due to the low mechanical restoring force of the wire. Thus, there is the trade-off between the stability of the system and the sensitivity. Here, we describe using a triangular optical cavity to overcome this limitation for reaching the SQL. The triangular cavity can provide a sensitive and stable system, because it can optically trap the mirror's motion of the yaw, through an optical positive torsional spring effect. To show this, we demonstrate a measurement of the torsional spring effect caused by radiation pressure forces.

Matsumoto, Nobuyuki; Michimura, Yuta; Aso, Yoichi; Tsubono, Kimio

2014-06-01

336

Optically trapped mirror for reaching the standard quantum limit.  

PubMed

The preparation of a mechanical oscillator driven by quantum back-action is a fundamental requirement to reach the standard quantum limit (SQL) for force measurement, in optomechanical systems. However, thermal fluctuating force generally dominates a disturbance on the oscillator. In the macroscopic scale, an optical linear cavity including a suspended mirror has been used for the weak force measurement, such as gravitational-wave detectors. This configuration has the advantages of reducing the dissipation of the pendulum (i.e., suspension thermal noise) due to a gravitational dilution by using a thin wire, and of increasing the circulating laser power. However, the use of the thin wire is weak for an optical torsional anti-spring effect in the cavity, due to the low mechanical restoring force of the wire. Thus, there is the trade-off between the stability of the system and the sensitivity. Here, we describe using a triangular optical cavity to overcome this limitation for reaching the SQL. The triangular cavity can provide a sensitive and stable system, because it can optically trap the mirror's motion of the yaw, through an optical positive torsional spring effect. To show this, we demonstrate a measurement of the torsional spring effect caused by radiation pressure forces. PMID:24921489

Matsumoto, Nobuyuki; Michimura, Yuta; Aso, Yoichi; Tsubono, Kimio

2014-06-01

337

Gating of vibrotactile detection during visually guided bimanual reaches.  

PubMed

It is far more difficult to detect a small tactile stimulation on a finger that is moving compared to when it is static. This suppression of tactile information during motion, known as tactile gating, has been examined in some detail during single-joint movements. However, the existence and time course of this gating has yet to be examined during visually guided multi-joint reaches, where sensory feedback may be paramount. The current study demonstrated that neurologically intact humans are unable to detect a small vibratory stimulus on one of their index fingers during a bimanual reach toward visual targets. By parametrically altering the delay between the visual target onset and the vibration, it was demonstrated that this gating was even apparent before participants started moving. A follow up experiment using electromyography indicated that gating was likely to occur even before muscle activity had taken place. This unique demonstration of tactile gating during a task reliant on visual feedback supports the notion this phenomenon is due to a central command, rather than a masking of sensory signals by afferent processing during movement. PMID:19851758

Buckingham, Gavin; Carey, David P; Colino, Francisco L; deGrosbois, John; Binsted, Gordon

2010-03-01

338

Reach-averaged sediment routing model of a canyon river  

USGS Publications Warehouse

Spatial complexity in channel geometry indicates that accurate prediction of sediment transport requires modeling in at least two dimensions. However, a one-dimensional model may be the only practical or possible alternative, especially for longer river reaches of practical concern in river management or landscape modeling. We have developed a one-dimensional model of the Colorado River through upper Grand Canyon that addresses this problem by reach averaging the channel properties and predicting changes in sand storage using separate source and sink functions coupled to the sand routing model. The model incorporates results from the application of a two-dimensional model of flow, sand transport, and bed evolution, and a new algorithm for setting the near-bed sand boundary condition for sand transported over an exposed bouldery bed. Model predictions were compared to measurements of sand discharge during intermittent tributary inputs and varying discharges controlled by dam releases. The model predictions generally agree well with the timing and magnitude of measured sand discharges but tend to overpredict sand discharge during the early stages of a high release designed to redistribute sand to higher-elevation deposits.

Wiele, S. M.; Wilcock, P. R.; Grams, P. E.

2007-01-01

339

Linognathus vituli (Anoplura: Linognathidae): population growth, dispersal and development of humoral immune responses in na??ve calves following induced infestations  

Microsoft Academic Search

Growth of Linognathus vituli populations following establishment at a point source was followed for 16 weeks on eight louse-na??ve Holstein calves. Dispersal of lice from the point of infestation (withers) was monitored by examination of known louse predilection sights. Mean louse indices increased during the initial weeks reaching maximum mean values at 8 weeks post-infestation (p.i.). Subsequently, mean indices decreased,

Douglas D Colwell; Christine Himsl-Rayner

2002-01-01

340

Batch maximum likelihood (ML) and maximum a posteriori (MAP) estimation with process noise for tracking applications  

Microsoft Academic Search

Batch maximum likelihood (ML) and maximum a posteriori (MAP) estimation with process noise is now more than thirty-five years old, and its use in multiple target tracking has long been considered to be too computationally intensive for real-time applications. While this may still be true for general usage, it is ideally suited for special needs such as bias estimation, track

Aubrey B. Poore; Benjamin J. Slocumb; Brian J. Suchomel; Fritz H. Obermeyer; Shawn M. Herman; Sabino M. Gadaleta

2004-01-01

341

Batch maximum likelihood (ML) and maximum a posteriori (MAP) estimation with process noise for tracking applications  

Microsoft Academic Search

Batch maximum likelihood (ML) and maximum a posteriori (MAP) estimation with process noise is now more than thirty-five years old, and its use in multiple target tracking has long been considered to be too computationally intensive for real-time applications. While this may still be true for general usage, it is ideally suited for special needs such as bias estimation, track

Aubrey B. Poore; Benjamin J. Slocumb; Brian J. Suchomel; Fritz H. Obermeyer; Shawn M. Herman; Sabino M. Gadaleta

2003-01-01

342

Batch Maximum Likelihood (ML) and Maximum A Posteriori (MAP) Estimation with Process Noise for Tracking Applications.  

National Technical Information Service (NTIS)

Batch maximum likelihood (ML) and maximum a posteriori (MAP) estimation with process noise is now more than thirty-five years old, and its use in multiple target tracking has long been considered to be too computationally intensive for real-time applicati...

A. B. Poore B. J. Slocumb B. J. Suchomel F. H. Obermeyer S. M. Herman

2003-01-01

343

Finding maximum colorful subtrees in practice.  

PubMed

In metabolomics and other fields dealing with small compounds, mass spectrometry is applied as a sensitive high-throughput technique. Recently, fragmentation trees have been proposed to automatically analyze the fragmentation mass spectra recorded by such instruments. Computationally, this leads to the problem of finding a maximum weight subtree in an edge-weighted and vertex-colored graph, such that every color appears, at most once in the solution. We introduce new heuristics and an exact algorithm for this Maximum Colorful Subtree problem and evaluate them against existing algorithms on real-world and artificial datasets. Our tree completion heuristic consistently scores better than other heuristics, while the integer programming-based algorithm produces optimal trees with modest running times. Our fast and accurate heuristic can help determine molecular formulas based on fragmentation trees. On the other hand, optimal trees from the integer linear program are useful if structure is relevant, for example for tree alignments. PMID:23509858

Rauf, Imran; Rasche, Florian; Nicolas, François; Böcker, Sebastian

2013-04-01

344

Deconvolution of planar scintigrams by maximum entropy.  

PubMed

Planar scintigrams are deconvolved with a point spread function using the maximum entropy method with the aim of improving image quality. The technique requires the specification of several parameters. These are related to the level of noise present in the data and our a priori knowledge of the object imaged. The performance of the technique is tested for a wide range of these parameters using images of a Williams phantom in scattering material and a figure of merit, derived from the detectability of the smallest cold spot, is calculated. For close to optimal values of the parameters a factor of two improvement in the figure is found. A processed bone image shows improved contrast and resolution. Maximum entropy processing could be used to increase image quality or allow comparable image quality with reduced imaging time or patient dose. PMID:7708837

Simpson, D E; Fleming, J S; Aldous, A J; Daniell, G J

1995-01-01

345

Maximum Noise Levels in City Traffic  

NASA Astrophysics Data System (ADS)

Manual and automatic noise measurements were made along 13 streets in Gothenburg, Sweden to explore sources of maximum noise levels. Noise from different types of vehicles driven in a realistic way in inner city traffic was measured. In summary, the results show that the most important vehicle component as regards the maximum noise level in inner city traffic was a medium-weight truck (delivery truck). Among the higher noise levels measured (>80 dB(A)), this type of vehicle is dominant. This is supported by tests that demonstrated that the noise level of a light truck, driven in a realistic way, exceeds that of cars and is on the same level as heavy trucks. Measures can be taken against the noisiest vehicle types specifically, and the noise load can be limited by introducing noise bans for particular streets in which vehicles that emit greater than a certain noise level would not be allowed use of the street.

Björkman, M.; Rylander, R.

1997-08-01

346

Maximum drag reduction simulation using rodlike polymers  

NASA Astrophysics Data System (ADS)

Simulations of maximum drag reduction (MDR) in channel flow using constitutive equations for suspensions of noninteracting rods predict a few-fold larger turbulent kinetic energy than in experiments using rodlike polymers. These differences are attributed to the neglect of interactions between polymers in the simulations. Despite these inconsistencies the simulations correctly reproduce the essential features of MDR, with universal profiles of the mean flow and the shear stress budgets that do not depend on the polymer concentration.

Gillissen, J. J. J.

2012-10-01

347

Maximum likelihood drift estimation for multiscale diffusions  

Microsoft Academic Search

We study the problem of parameter estimation using maximum likelihood for fast\\/slow systems of stochastic differential equations. Our aim is to shed light on the problem of model\\/data mismatch at small scales. We consider two classes of fast\\/slow problems for which a closed coarse-grained equation for the slow variables can be rigorously derived, which we refer to as averaging and

A. Papavasiliou; G. A. Pavliotis; A. M. Stuart

2009-01-01

348

Maximum Likelihood Drift Estimation for Multiscale Diffusions  

Microsoft Academic Search

We study the problem of parameter estimation using maximum likelihood for fast\\/slow systems of stochastic differential equations. Our aim is to shed light on the problem of model\\/data mismatch at small scales. We consider two classes of fast\\/slow problems for which a closed coarse-grained equation for the slow variables can be rigorously derived, which we refer to as averaging and

A. Papavasiliou; G. A. Pavliotis; A. M. Stuart

2008-01-01

349

Maximum entropy and Bayesian methods. Proceedings.  

NASA Astrophysics Data System (ADS)

This volume contains a selection of papers presented at the Tenth Annual Workshop on Maximum Entropy and Bayesian Methods. The thirty-six papers included cover a wide range of applications in areas such as economics and econometrics, astronomy and astrophysics, general physics, complex systems, image reconstruction, and probability and mathematics. Together they give an excellent state-of-the-art overview of fundamental methods of data analysis.

Grandy, W. T., Jr.; Schick, L. H.

350

Critical thermal maximum of seven estuarine fishes  

Microsoft Academic Search

Critical thermal maximum (CTM) and loss of righting response (LRR) were determined in seven estuarine fishes. The critical thermal maxima (CTM) ranged from 39.5°C to 44.5°C for fishes acclimated to 28°C. Lates calcarifer and Liza dussumeri had the highest CTM (44.5°C) and Siganus javus had the lowest CTM (39.5°C). The rate of change of CTM due to thermal acclimation was

S. Rajaguru

2002-01-01

351

Maximum entropy production - Full steam ahead  

NASA Astrophysics Data System (ADS)

The application of a principle of Maximum Entropy Production (MEP, or less ambiguously MaxEP) to planetary climate is discussed. This idea suggests that if sufficiently free of dynamical constraints, the atmospheric and oceanic heat flows across a planet may conspire to maximize the generation of mechanical work, or entropy. Thermodynamic and information-theoretic aspects of this idea are discussed. These issues are also discussed in the context of dust devils, convective vortices found in strongly-heated desert areas.

Lorenz, Ralph D.

2012-05-01

352

The maximum bias of robust covariances  

Microsoft Academic Search

This paper deals with the maximum asymptotic bias of two classes of robust estimates of the dispersion matrix V of a p-dimensional random vector x, under a contamination model of the form , where P is the distribution of x,P0 is a spherical distribution, and ?(x0) is a point mass at x0. Estimators VQ,? of the first class minimize the

Yohai J. Victor; Maronna A. Ricardo

1990-01-01

353

Maximum Mass of a Neutron Star  

Microsoft Academic Search

On the basis of Einstein's theory of relativity, the principle of causality, and Le Chatelier's principle, it is here established that the maximum mass of the equilibrium configuration of a neutron star cannot be larger than 3.2M[m?]. The extremal principle given here applies as well when the equation of state of matter is unknown in a limited range of densities.

Clifford E. Rhoades; Remo Ruffini

1974-01-01

354

Maximum Correntropy Criterion for Robust Face Recognition  

Microsoft Academic Search

In this paper, we present a sparse correntropy framework for computing robust sparse representations of face images for recognition. Compared with the state-of-the-art l 1 norm-based sparse representation classifier (SRC), which assumes that noise also has a sparse representation, our sparse algorithm is developed based on the maximum correntropy criterion, which is much more insensitive to outliers. In order to

Ran He; Wei-Shi Zheng; Bao-Gang Hu

2011-01-01

355

Identifying Semantic Roles Using Maximum Entropy Models  

Microsoft Academic Search

\\u000a In this paper, a supervised learning method of semantic role labeling is presented. It is based on maximum entropy conditional probability models. This method acquires the linguistic knowledge from an annotated corpus and this knowledge is represented in the form of\\u000a features. Several types of features have been analyzed for a few words selected from sections of the Wall Street

Paloma Moreda; Manuel Fernández; Manuel Palomar; Armando Suárez

2004-01-01

356

The maximum rate of mammal evolution.  

PubMed

How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes. PMID:22308461

Evans, Alistair R; Jones, David; Boyer, Alison G; Brown, James H; Costa, Daniel P; Ernest, S K Morgan; Fitzgerald, Erich M G; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; Okie, Jordan G; Saarinen, Juha J; Sibly, Richard M; Smith, Felisa A; Stephens, Patrick R; Theodor, Jessica M; Uhen, Mark D

2012-03-13

357

"SPURS" in the North Atlantic Salinity Maximum  

NASA Astrophysics Data System (ADS)

The North Atlantic Salinity Maximum is the world's saltiest open ocean salinity maximum and was the focus of the recent Salinity Processes Upper-ocean Regional Study (SPURS) program. SPURS was a joint venture between US, French, Irish, and Spanish investigators. Three US and two EU cruises were involved from August, 1012 - October, 2013 as well as surface moorings, glider, drifter and float deployments. Shipboard operations included underway meteorological and oceanic data, hydrographic surveys and turbulence profiling. The goal is to improve our understanding of how the salinity maximum is maintained and how it may be changing. It is formed by an excess of evaporation over precipitation and the wind-driven convergence of the subtropical gyre. Such salty areas are getting saltier with global warming (a record high SSS was observed in SPURS) and it is imperative to determine the relative roles of surface water fluxes and oceanic processes in such trends. The combination of accurate surface flux estimates with new assessments of vertical and horizontal mixing in the ocean will help elucidate the utility of ocean salinity in quantifying the changing global water cycle.

Schmitt, Raymond

2014-05-01

358

Global CO2 rise leads to reduced maximum stomatal conductance in Florida vegetation  

PubMed Central

A principle response of C3 plants to increasing concentrations of atmospheric CO2 (CO2) is to reduce transpirational water loss by decreasing stomatal conductance (gs) and simultaneously increase assimilation rates. Via this adaptation, vegetation has the ability to alter hydrology and climate. Therefore, it is important to determine the adaptation of vegetation to the expected anthropogenic rise in CO2. Short-term stomatal opening–closing responses of vegetation to increasing CO2 are described by free-air carbon enrichments growth experiments, and evolutionary adaptations are known from the geological record. However, to date the effects of decadal to centennial CO2 perturbations on stomatal conductance are still largely unknown. Here we reconstruct a 34% (±12%) reduction in maximum stomatal conductance (gsmax) per 100 ppm CO2 increase as a result of the adaptation in stomatal density (D) and pore size at maximal stomatal opening (amax) of nine common species from Florida over the past 150 y. The species-specific gsmax values are determined by different evolutionary development, whereby the angiosperms sampled generally have numerous small stomata and high gsmax, and the conifers and fern have few large stomata and lower gsmax. Although angiosperms and conifers use different D and amax adaptation strategies, our data show a coherent response in gsmax to CO2 rise of the past century. Understanding these adaptations of C3 plants to rising CO2 after decadal to centennial environmental changes is essential for quantification of plant physiological forcing at timescales relevant for global warming, and they are likely to continue until the limits of their phenotypic plasticity are reached.

Lammertsma, Emmy I.; de Boer, Hugo Jan; Dekker, Stefan C.; Dilcher, David L.; Lotter, Andre F.; Wagner-Cremer, Friederike

2011-01-01

359

Global CO2 rise leads to reduced maximum stomatal conductance in Florida vegetation.  

PubMed

A principle response of C3 plants to increasing concentrations of atmospheric CO(2) (CO(2)) is to reduce transpirational water loss by decreasing stomatal conductance (g(s)) and simultaneously increase assimilation rates. Via this adaptation, vegetation has the ability to alter hydrology and climate. Therefore, it is important to determine the adaptation of vegetation to the expected anthropogenic rise in CO(2). Short-term stomatal opening-closing responses of vegetation to increasing CO(2) are described by free-air carbon enrichments growth experiments, and evolutionary adaptations are known from the geological record. However, to date the effects of decadal to centennial CO(2) perturbations on stomatal conductance are still largely unknown. Here we reconstruct a 34% (±12%) reduction in maximum stomatal conductance (g(smax)) per 100 ppm CO(2) increase as a result of the adaptation in stomatal density (D) and pore size at maximal stomatal opening (a(max)) of nine common species from Florida over the past 150 y. The species-specific g(smax) values are determined by different evolutionary development, whereby the angiosperms sampled generally have numerous small stomata and high g(smax), and the conifers and fern have few large stomata and lower g(smax). Although angiosperms and conifers use different D and a(max) adaptation strategies, our data show a coherent response in g(smax) to CO(2) rise of the past century. Understanding these adaptations of C3 plants to rising CO(2) after decadal to centennial environmental changes is essential for quantification of plant physiological forcing at timescales relevant for global warming, and they are likely to continue until the limits of their phenotypic plasticity are reached. PMID:21330552

Lammertsma, Emmy I; de Boer, Hugo Jan; Dekker, Stefan C; Dilcher, David L; Lotter, André F; Wagner-Cremer, Friederike

2011-03-01

360

Spectroscopy of the very fast Nova Del 2013, already declining past maximum brightness  

NASA Astrophysics Data System (ADS)

Nova Del 2013 seems to have reached maximum brightness on August 16.45 UT at V=4.3 mag. It immediately entered the decline phase and it is declining pretty fast, of the order of 1 mag in a day, qualifying it as a very fast nova if the pace will be maintained on the coming days. Also the rise toward maximum has been real fast, 2 mag in about 1.5 days according to our photometry and AAVSO database. The total outburst amplitude is 12.6 mag in V, adopting V=16.9 mag for the progenitor as given by GSC 2.3.2.

Munari, U.; Valisa, P.; Milani, A.; Cetrulo, G.

2013-08-01

361

On the maximum energy and escape of accelerated particles in young supernova remnants  

NASA Astrophysics Data System (ADS)

Using analytic expressions and self-similar solutions, we explore different environments in which supernova remnants (SNRs) evolve, and investigate how the maximum energy to which particles are accelerated, and its time evolution, is a function of the complex environment. We take into account the ambient magnetic field and its amplification by resonant or non-resonant modes. We find that particles reach the maximum energies in the ejecta-dominated stage, much earlier than Sedov stage, particularly in the case of core-collapse SNe expanding in the winds of massive stars.

Dwarkadas, Vikram V.; Telezhinsky, Igor; Pohl, Martin

2012-12-01

362

Enhancement of the maximum energy density in atomic layer deposited oxide based thin film capacitors  

NASA Astrophysics Data System (ADS)

Thin film capacitors on areas up to 6 mm2 have been measured regarding capacitance density, relative permittivity, and electrical breakdown. The maximum storable energy density of the thin film capacitors will be discussed as a parameter to evaluate the thin film capacitors applicability. Therefore the measurements of the layer thickness, capacitance density, and the breakdown voltage were combined to achieve the maximum storable areal and volume energy density depending on the dielectric layer thickness. Thickness dependent volume energy densities of up to 50 J/cm3 for pure Al2O3 and 60 J/cm3 for Al2O3/TiO2 nanolaminates were reached.

Spahr, Holger; Nowak, Christine; Hirschberg, Felix; Reinker, Johannes; Kowalsky, Wolfgang; Hente, Dirk; Johannes, Hans-Hermann

2013-07-01

363

Automatic online control of motor adjustments in reaching and grasping.  

PubMed

Following the princeps investigations of Marc Jeannerod on action-perception, specifically, goal-directed movement, this review article addresses visual and non-visual processes involved in guiding the hand in reaching or grasping tasks. The contributions of different sources of correction of ongoing movements are considered; these include visual feedback of the hand, as well as the often-neglected but important spatial updating and sharpening of goal localization following gaze-saccade orientation. The existence of an automatic online process guiding limb trajectory toward its goal is highlighted by a series of princeps experiments of goal-directed pointing movements. We then review psychophysical, electrophysiological, neuroimaging and clinical studies that have explored the properties of these automatic corrective mechanisms and their neural bases, and established their generality. Finally, the functional significance of automatic corrective mechanisms-referred to as motor flexibility-and their potential use in rehabilitation are discussed. PMID:24334110

Gaveau, Valérie; Pisella, Laure; Priot, Anne-Emmanuelle; Fukui, Takao; Rossetti, Yves; Pélisson, Denis; Prablanc, Claude

2014-03-01

364

Extended reach drilling eliminates need for artificial island  

SciTech Connect

Four wells have been drilled in the Wytch Farm ERD project and the time/depth performance has dramatically improved with each. While operations are approaching current technology limits, new developments such as rotary steerable systems will allow even more aggressive ERD objectives. Wytch Farm oil field, located southwest of London on the coast near Poole, England, is operated by BP Exploration. The main producing reservoir is the Sherwood Triassic sandstone, which contains about 270 million bbl of recoverable oil at 5,200 ft TVD. A bout a third of the Sherwood`s reserves are offshore. Plans to develop the offshore portions of the reservoir using an artificial island were canceled in favor of extended reach drilling (ERD) from an onshore drill site. Use of ERD and elimination of the island are expected to save $150 million in development costs and should accelerate the production of offshore oil by 3 years.

Cocking, D.A.; Payne, M.L.; Hatch, A.J.

1995-02-01

365

Computing reaching dynamics in motor cortex with Cartesian spatial coordinates  

PubMed Central

How neurons in the primary motor cortex control arm movements is not yet understood. Here we show that the equations of motion governing reaching simplify when expressed in spatial coordinates. In this fixed reference frame, joint torques are the sums of vector cross products between the spatial positions of limb segments and their spatial accelerations and velocities. The consequences that follow from this model explain many properties of neurons in the motor cortex, including directional broad, cosinelike tuning, nonuniformly distributed preferred directions dependent on the workspace, and the rotation of the population vector during arm movements. Remarkably, the torques can be directly computed as a linearly weighted sum of responses from cortical motoneurons, and the muscle tensions can be obtained as rectified linear sums of the joint torques. This allows the required muscle tensions to be computed rapidly from a trajectory in space with a feedforward network model.

Sejnowski, Terrence J.

2013-01-01

366

Coding of the reach vector in parietal area 5d  

PubMed Central

Summary Competing models of sensorimotor computation predict different topological constraints in the brain. Some models propose population coding of particular reference frames in anatomically distinct nodes, whereas others require no such dedicated subpopulations and instead predict that regions will simultaneously code in multiple, intermediate, reference frames. Current empirical evidence is conflicting, partly due to difficulties involved in identifying underlying reference frames. Here, we independently varied the locations of hand, gaze and target over many positions while recording from the dorsal aspect of parietal area 5. We find that the target is represented in a predominantly hand-centered reference frame here, contrasting with the relative code seen in dorsal premotor cortex and the mostly gaze-centered reference frame in the parietal reach region. This supports the hypothesis that different nodes of the sensorimotor circuit contain distinct and systematic representations, and this constrains the types of computational model that are neurobiologically relevant.

Bremner, Lindsay R.; Andersen, Richard A.

2012-01-01

367

Supersymmetry reach of Fermilab Tevatron upgrades: A comparative study  

NASA Astrophysics Data System (ADS)

We use ISAJET to perform a detailed comparison of the supersymmetry reach of the current Fermilab Tevatron (100 pb-1) with that of the Main Injector (2 fb-1) and the proposed TeV33 upgrade designed to yield an integrated luminosity of 25 fb-1. Our analysis is performed within the framework of the minimal supergravity model with gauge coupling unification and radiative electroweak symmetry breaking. For each of these three luminosity options, we delineate the regions of parameter space where jets plus missing energy plus 0, 1, 2 (opposite-sign and same-sign dileptons), and 3 isolated lepton signals from the cascade decays of sparticles should be visible above standard model backgrounds. We compare these with the parameter regions where signals in the clean isolated dilepton and trilepton channels (from chargino or neutralino and slepton production) should be observable.

Baer, Howard; Chen, Chih-Hao; Paige, Frank; Tata, Xerxes

1996-11-01

368

The long reach of Alzheimer's disease: patients, practice, and policy.  

PubMed

The impact of Alzheimer's disease and related dementias reaches well beyond the health care needs of the person with dementia. As dementia inexorably progresses, the patient becomes increasingly dependent on others for basic daily care and routine tasks, a physically safe environment, and protection from exploitation or abuse. Addressing the diverse medical and social care needs of the burgeoning US population with Alzheimer's disease and related dementias requires the adoption of a broad-based policy framework and agenda that explicitly acknowledge the complex and unique needs of people with dementia and the impacts of dementia on caregivers and society at large. Public policies related to social service providers, agencies that provide appropriate housing, financial and legal services, and law enforcement must complement other policies focused on prevention and risk reduction, effective treatment development, and efficient health care delivery. PMID:24711311

Bynum, Julie P W

2014-04-01

369

QSPR prediction of physico-chemical properties for REACH.  

PubMed

For registration of a chemical, European Union REACH legislation requires information on the relevant physico-chemical properties of the chemical. Predicted property values can be used when the predictions can be shown to be valid and adequate. The relevant physico-chemical properties that are amenable to prediction are: melting/freezing point, boiling point, relative density, vapour pressure, surface tension, water solubility, n-octanol-water partition coefficient, flash point, flammability, explosive properties, self-ignition temperature, adsorption/desorption, dissociation constant, viscosity, and air-water partition coefficient (Henry's law constant). Published quantitative structure-property relationship (QSPR) methods for all of these properties are discussed, together with relevant property prediction software, as an aid for those wishing to use predicted property values in submissions to the European Chemicals Agency (ECHA). PMID:23521394

Dearden, J C; Rotureau, P; Fayet, G

2013-01-01

370

Walking Is Not Like Reaching: Evidence from Periodic Mechanical Perturbations  

PubMed Central

The control architecture underlying human reaching has been established, at least in broad outline. However, despite extensive research, the control architecture underlying human locomotion remains unclear. Some studies show evidence of high-level control focused on lower-limb trajectories; others suggest that nonlinear oscillators such as lower-level rhythmic central pattern generators (CPGs) play a significant role. To resolve this ambiguity, we reasoned that if a nonlinear oscillator contributes to locomotor control, human walking should exhibit dynamic entrainment to periodic mechanical perturbation; entrainment is a distinctive behavior of nonlinear oscillators. Here we present the first behavioral evidence that nonlinear neuro-mechanical oscillators contribute to the production of human walking, albeit weakly. As unimpaired human subjects walked at constant speed, we applied periodic torque pulses to the ankle at periods different from their preferred cadence. The gait period of 18 out of 19 subjects entrained to this mechanical perturbation, converging to match that of the perturbation. Significantly, entrainment occurred only if the perturbation period was close to subjects' preferred walking cadence: it exhibited a narrow basin of entrainment. Further, regardless of the phase within the walking cycle at which perturbation was initiated, subjects' gait synchronized or phase-locked with the mechanical perturbation at a phase of gait where it assisted propulsion. These results were affected neither by auditory feedback nor by a distractor task. However, the convergence to phase-locking was slow. These characteristics indicate that nonlinear neuro-mechanical oscillators make at most a modest contribution to human walking. Our results suggest that human locomotor control is not organized as in reaching to meet a predominantly kinematic specification, but is hierarchically organized with a semi-autonomous peripheral oscillator operating under episodic supervisory control.

Ahn, Jooeun; Hogan, Neville

2012-01-01

371

Hydrogen induced crack growth in Grade-12 titanium  

SciTech Connect

Internal hydrogen induced crack growth rates were measured in Grade-12 titanium which is a candidate material for high-level nuclear waste containers. As-received and hydrogen charged samples (5 ppM to 330 ppM hydrogen) were used for slow crack growth measurements at constant loads using a Krak Gauge. The testing temperature ranged from room temperature to 148/sup 0/C. The crack growth kinetics under low to moderate loads are linear, but this linear rate is interrupted by discrete fast crack jump segments with parabolic or cubic type kinetics. These fast jump segments are thought to be associated with the passage of the crack front through the alpha-beta interface phase or with the initial loading sequence. By measuring striation spacings on the fracture surface, most crack growth rates observed are found to be in stage II. The striations are considered to be associated with hydride fracture. The crack path is either transgranular in the alpha phase or interfacial in the alpha phase adjacent to the beta phase. For transgranular growth, crack growth rates are constant and slower than those for interfacial growth which is associated with fast crack growth through a high hydrogen concentration region. Most stage II crack growth rates depend slightly on the stress intensity suggesting the contribution of plastic tearing process to stage II kinetics. The activation energies for crack growth are much lower than the activation energy of hydrogen diffusion through the alpha phase, implying that hydrogen is transported along dislocations, grain boundaries or interfaces. When the temperature is increased, the crack velocity first reaches a maximum and then decreases at higher temperatures. These temperature effects come from lower hydrogen concentration trapped at dislocations or from slower hydride nucleation kinetics, both at higher temperatures.

Ahn, T.M.; Lee, K.S.

1984-01-01

372

Evaluation of influence of historical changes in land use along the middle Vistula river reach on flood risk  

NASA Astrophysics Data System (ADS)

There is a vast literature on the influence of land use changes on rainfall-runoff processes. The problem is difficult as it requires separation of climatic and water management related changes from land use influences. The present paper addresses the problem of the influence of land use changes on maximum flows at cross-sections along the middle River Vistula reach. We adopt a methodology tested at the catchment scale, which consists of an optimisation of a rainfall-runoff model using a moving time horizon and analysis of the variability of model parameters. In the present application, it consists of an analysis of changes of roughness coefficients of a distributed HEC-RAS model, optimised using a moving five-year window. The chosen river reach (between Annopol and Gusin) has a recorded history of land use changes over 50 years (from 1949 to 2001), which included 36% of the study area. The nature of the changes is complex and shows different trends for different plant communities and sections of the valley. Generally, there has been a several percent increase in the area occupied by forests and grassland communities and a slight increase in the proportion of scrub. The first step of the procedure is to define the river reaches that have recorded information on land use changes. The second step is to perform a moving window optimisation of the HEC-RAS model for a chosen river reach. In order to assess the influence of land use changes on maximum flow values, the goodness-of-fit of the simulation of annual maximum water levels is used as an optimisation criterion. In this way the influence of land use changes on maximum inundation extent related to flood risk assessment can be estimated. The final step is to analyse the results and relate the model parameter changes to historical land use changes. We report here the results of the first two steps of the procedure. This work was partly supported from the project "Stochastic flood forecasting system (The River Vistula reach from Zawichost to Warsaw)" carried out by the Institute of Geophysics, Polish Academy of Sciences on the order of the National Science Centre (contract No. 2011/01/B/ST10/06866). The water level and flow data were provided by the Institute of Meteorology and Water Management (IMGW), Poland.

Karamuz, Emilia; Romanowicz, Renata; Booij, Martijn

2014-05-01

373

Estimating maximum performance: effects of intraindividual variation.  

PubMed

Researchers often estimate the performance capabilities of animals using a small number of trials per individual. This procedure inevitably underestimates maximum performance, but few studies have examined the magnitude of this effect. In this study we explored the effects of intraindividual variation and individual sample size on the estimation of locomotor performance parameters. We measured sprint speed of the lizard Sceloporus occidentalis at two temperatures (20 degrees C and 35 degrees C), obtaining 20 measurements per individual. Speed did not vary temporally, indicating no training or fatigue effects. About 50% of the overall variation in speed at each temperature was due to intraindividual variation. While speed was repeatable, repeatability decreased slightly with increasing separation between trials. Speeds at 20 degrees C and 35 degrees C were positively correlated, indicating repeatability across temperatures as well. We performed statistical sampling experiments in which we randomly drew a subset of each individual's full set of 20 trials. As expected, the sample's maximum speed increased with the number of trials per individual; for example, five trials yielded an estimate averaging 89% of the true maximum. The number of trials also influenced the sample correlation between mean speeds at 20 degrees C and 35 degrees C; for example, five trials yielded a correlation coefficient averaging 90% of the true correlation. Therefore, intraindividual variation caused underestimation of maximal speed and the correlation between speeds across temperatures. These biases declined as the number of trials per individual increased, and depended on the magnitude of intraindividual variation, as illustrated by running sampling experiments that used modified data sets. PMID:18375858

Adolph, Stephen C; Pickering, Trevor

2008-04-01

374

Stoichiometric identification with maximum likelihood principal component analysis.  

PubMed

This study presents an effective procedure for the determination of a biologically inspired, black-box model of cultures of microorganisms (including yeasts, bacteria, plant and animal cells) in bioreactors. This procedure is based on sets of experimental data measuring the time-evolution of a few extracellular species concentrations, and makes use of maximum likelihood principal component analysis to determine, independently of the kinetics, an appropriate number of macroscopic reactions and their stoichiometry. In addition, this paper provides a discussion of the geometric interpretation of a stoichiometric matrix and the potential equivalent reaction schemes. The procedure is carefully evaluated within the stoichiometric identification framework of the growth of the yeast Kluyveromyces marxianus on cheese whey. Using Monte Carlo studies, it is also compared with two other previously published approaches. PMID:22821205

Mailier, Johan; Remy, Marcel; Vande Wouwer, Alain

2013-10-01

375

Dynamical maximum entropy approach to flocking  

NASA Astrophysics Data System (ADS)

We derive a new method to infer from data the out-of-equilibrium alignment dynamics of collectively moving animal groups, by considering the maximum entropy model distribution consistent with temporal and spatial correlations of flight direction. When bird neighborhoods evolve rapidly, this dynamical inference correctly learns the parameters of the model, while a static one relying only on the spatial correlations fails. When neighbors change slowly and the detailed balance is satisfied, we recover the static procedure. We demonstrate the validity of the method on simulated data. The approach is applicable to other systems of active matter.

Cavagna, Andrea; Giardina, Irene; Ginelli, Francesco; Mora, Thierry; Piovani, Duccio; Tavarone, Raffaele; Walczak, Aleksandra M.

2014-04-01

376

The 2009 Perseid Maximum - Photographic Results  

NASA Astrophysics Data System (ADS)

An astronomical camp was organized by Comet and Meteors Workshop during the 2009 Perseids maximum. 69 meteors were photographed during four consecutive nights. We found that photographic Perseid radiant was very compact and located at alpha=48.7 deg, delta=58.6 deg. Our main goal was the determination of the radiant from single station photographic observations, however we also calculated two double station trajectories using additional data which were send to us by casual photographic observer from other parts of Poland. Dozens of radio reflections were observed with simple radio receiver, some of them were identified with photographic images.

Zolcadek, P.; Wisniewski, M.; Polakowski, K.; Wala, E.; Walczak, K.; Poleski, R.

2010-01-01

377

Maximum a posteriori decoder for digital communications  

NASA Technical Reports Server (NTRS)

A system and method for decoding by identification of the most likely phase coded signal corresponding to received data. The present invention has particular application to communication with signals that experience spurious random phase perturbations. The generalized estimator-correlator uses a maximum a posteriori (MAP) estimator to generate phase estimates for correlation with incoming data samples and for correlation with mean phases indicative of unique hypothesized signals. The result is a MAP likelihood statistic for each hypothesized transmission, wherein the highest value statistic identifies the transmitted signal.

Altes, Richard A. (Inventor)

1997-01-01

378

Maximum aposteriori joint source/channel coding  

NASA Technical Reports Server (NTRS)

A maximum aposteriori probability (MAP) approach to joint source/channel coder design is presented in this paper. This method attempts to explore a technique for designing joint source/channel codes, rather than ways of distributing bits between source coders and channel coders. For a nonideal source coder, MAP arguments are used to design a decoder which takes advantage of redundancy in the source coder output to perform error correction. Once the decoder is obtained, it is analyzed with the purpose of obtaining 'desirable properties' of the channel input sequence for improving overall system performance. Finally, an encoder design which incorporates these properties is proposed.

Sayood, Khalid; Gibson, Jerry D.

1991-01-01

379

Dynamical maximum entropy approach to flocking.  

PubMed

We derive a new method to infer from data the out-of-equilibrium alignment dynamics of collectively moving animal groups, by considering the maximum entropy model distribution consistent with temporal and spatial correlations of flight direction. When bird neighborhoods evolve rapidly, this dynamical inference correctly learns the parameters of the model, while a static one relying only on the spatial correlations fails. When neighbors change slowly and the detailed balance is satisfied, we recover the static procedure. We demonstrate the validity of the method on simulated data. The approach is applicable to other systems of active matter. PMID:24827278

Cavagna, Andrea; Giardina, Irene; Ginelli, Francesco; Mora, Thierry; Piovani, Duccio; Tavarone, Raffaele; Walczak, Aleksandra M

2014-04-01

380

Control of aperture closure during reach-to-grasp movements in parkinson's disease  

PubMed Central

This study examined whether the pattern of coordination between arm-reaching toward an object (hand transport) and the initiation of aperture closure for grasping is different between PD patients and healthy individuals, and whether that pattern is affected by the necessity to quickly adjust the reach-to-grasp movement in response to an unexpected shift of target location. Subjects reached for and grasped a vertical dowel, the location of which was indicated by illuminating one of the three dowels placed on a horizontal plane. In control conditions, target location was fixed during the trial. In perturbation conditions, target location was shifted instantaneously by switching the illumination to a different dowel during the reach. The hand distance from the target at which the subject initiated aperture closure (aperture closure distance) was similar for both the control and perturbation conditions within each group of subjects. However, that distance was significantly closer to the target in the PD group than in the control group. The timing of aperture closure initiation varied considerably across the trials in both groups of subjects. In contrast, aperture closure distance was relatively invariant, suggesting that aperture closure initiation was determined by spatial parameters of arm kinematics rather than temporal parameters. The linear regression analysis of aperture closure distance showed that the distance was highly predictable based on the following three parameters: the amplitude of maximum grip aperture, hand velocity, and hand acceleration. This result implies that a control law, the arguments of which include the above parameters, governs the initiation of aperture closure. Further analysis revealed that the control law was very similar between the subject groups under each condition as well as between the control and perturbation conditions for each group. Consequently, the shorter aperture closure distance observed in PD patients apparently is a result of the hypometria of their grip aperture and bradykinesia of hand transport movement, rather than a consequence of a deficit in transport-grasp coordination. It is also concluded that the perturbation of target location does not disrupt the transport-grasp coordination in either healthy individuals or PD patients.

Rand, M. K.; Smiley-Oyen, A. L.; Shimansky, Y. P.; Bloedel, J. R.; Stelmach, G. E.

2007-01-01

381

An Improved Maximum Neural Network with Stochastic Dynamics Characteristic for Maximum Clique Problem  

NASA Astrophysics Data System (ADS)

Through analyzing the dynamics characteristic of maximum neural network with an added vertex, we find that the solution quality is mainly determined by the added vertex weights. In order to increase maximum neural network ability, a stochastic nonlinear self-feedback and flexible annealing strategy are embedded in maximum neural network, which makes the network more powerful to escape local minima and be independent of the initial values. Simultaneously, we present that solving ability of maximum neural network is dependence on problem. We introduce a new parameter into our network to improve the solving ability. The simulation in k random graph and some DIMACS clique instances in the second DIMACS challenge shows that our improved network is superior to other algorithms in light of the solution quality and CPU time.

Yang, Gang; Tang, Zheng; Dai, Hongwei

382

Application of maximum entropy method for droplet size distribution prediction using instability analysis of liquid sheet  

Microsoft Academic Search

This paper describes the implementation of the instability analysis of wave growth on liquid jet surface, and maximum entropy\\u000a principle (MEP) for prediction of droplet diameter distribution in primary breakup region. The early stage of the primary\\u000a breakup, which contains the growth of wave on liquid–gas interface, is deterministic; whereas the droplet formation stage\\u000a at the end of primary breakup

E. Movahednejad; F. Ommi; S. M. Hosseinalipour; C. P. Chen; S. A. Mahdavi

383

Resistivity maximum during Guinier-Preston zone formation in an Al4 wt% Cu alloy  

Microsoft Academic Search

In order to examine the scattering of conduction electrons from Guinier-Preston (GP) zones, the electrical resistivity (?) and the Hall coefficient have been measured. Quantitative information on the microstructure of aged alloys was obtained from small-angle X-ray scattering measurements. The resistivity behaves anomalously during isothermal ageing; it increases to a maximum, then decreases and reaches a value corresponding to the

Kozo Osamura; Naotaka Otsuka; Yotaro Murakami

1982-01-01

384

Selective conversion of bio-oil to light olefins: Controlling catalytic cracking for maximum olefins  

Microsoft Academic Search

Light olefins are the basic building blocks for the petrochemical industry. In this work, selective production of light olefins from catalytic cracking of bio-oil was performed by using the La\\/HZSM-5 catalyst. With a nearly complete conversion of bio-oil, the maximum yield reached 0.28±0.02kg olefins\\/(kg bio-oil), which was close to that from methanol. Addition of La into zeolite efficiently changed the

Feiyan Gong; Zhi Yang; Chenggui Hong; Weiwei Huang; Shen Ning; Zhaoxia Zhang; Yong Xu; Quanxin Li

2011-01-01

385

Metabolic networks evolve towards states of maximum entropy production  

PubMed Central

A metabolic network can be described by a set of elementary modes or pathways representing discrete metabolic states that support cell function. We have recently shown that in the most likely metabolic state the usage probability of individual elementary modes is distributed according to the Boltzmann distribution law while complying with the principle of maximum entropy production. To demonstrate that a metabolic network evolves towards such state we have carried out adaptive evolution experiments with Thermoanaerobacterium saccharolyticum operating with a reduced metabolic functionality based on a reduced set of elementary modes. In such reduced metabolic network metabolic fluxes can be conveniently computed from the measured metabolite secretion pattern. Over a time span of 300 generations the specific growth rate of the strain continuously increased together with a continuous increase in the rate of entropy production. We show that the rate of entropy production asymptotically approaches the maximum entropy production rate predicted from the state when the usage probability of individual elementary modes is distributed according to the Boltzmann distribution. Therefore, the outcome of evolution of a complex biological system can be predicted in highly quantitative terms using basic statistical mechanical principles.

Unrean, Pornkamol; Srienc, Friedrich

2011-01-01

386

Vegetation controls on the maximum size of coastal dunes.  

PubMed

Coastal dunes, in particular foredunes, support a resilient ecosystem and reduce coastal vulnerability to storms. In contrast to dry desert dunes, coastal dunes arise from interactions between biological and physical processes. Ecologists have traditionally addressed coastal ecosystems by assuming that they adapt to preexisting dune topography, whereas geomorphologists have studied the properties of foredunes primarily in connection to physical, not biological, factors. Here, we study foredune development using an ecomorphodynamic model that resolves the coevolution of topography and vegetation in response to both physical and ecological factors. We find that foredune growth is eventually limited by a negative feedback between wind flow and topography. As a consequence, steady-state foredunes are scale invariant, which allows us to derive scaling relations for maximum foredune height and formation time. These relations suggest that plant zonation (in particular for strand "dune-building" species) is the primary factor controlling the maximum size of foredunes and therefore the amount of sand stored in a coastal dune system. We also find that aeolian sand supply to the dunes determines the timescale of foredune formation. These results offer a potential explanation for the empirical relation between beach type and foredune size, in which large (small) foredunes are found on dissipative (reflective) beaches. Higher waves associated with dissipative beaches increase the disturbance of strand species, which shifts foredune formation landward and thus leads to larger foredunes. In this scenario, plants play a much more active role in modifying their habitat and altering coastal vulnerability than previously thought. PMID:24101481

Durán, Orencio; Moore, Laura J

2013-10-22

387

Vegetation controls on the maximum size of coastal dunes  

NASA Astrophysics Data System (ADS)

Coastal dunes, in particular foredunes, support a resilient ecosystem and reduce coastal vulnerability to storms. In contrast to dry desert dunes, coastal dunes arise from interactions between biological and physical processes. Ecologists have traditionally addressed coastal ecosystems by assuming that they adapt to preexisting dune topography, whereas geomorphologists have studied the properties of foredunes primarily in connection to physical, not biological, factors. Here, we study foredune development using an ecomorphodynamic model that resolves the co-evolution of topography and vegetation in response to both physical and ecological factors. We find that foredune growth is eventually limited by a negative feedback between wind flow and topography. As a consequence, steady state foredunes are scale invariant, which allows us to derive scaling relations for maximum foredune height and formation time. These relations suggest that plant zonation (in particular for strand `dune-building' species) is the primary factor controlling the maximum size of foredunes and therefore the amount of sand stored in a coastal dune system. We also find that aeolian sand supply to the dunes determines the time scale of foredune formation. These results offer a potential explanation for the empirical relation between beach type and foredune size, in which large (small) foredunes are found on dissipative (reflective) beaches: higher waves associated with dissipative beaches increase the disturbance of strand species which shifts foredune formation landwards and thus leads to larger foredunes.

Duran Vinent, Orencio; Moore, Laura J.

2014-05-01

388

Probably maximum flood of the Sava River  

NASA Astrophysics Data System (ADS)

The Nuclear Power Plant Krško (NEK) situated on the left bank of the Save River close to the border of Croatia. Probably Maximum Flood, on the location of the NEK could result in combination of probably maximum precipitation, sequential storm before PMP or snowmelt on the Sava River watershed. Mediterranean climate characterises very high precipitation and temporary high snow pack. The HBV-96 model as Integrated Hydrological Modelling System (IHMS) used for modelling. Model was calibrated and verification for daily time step at first for time period 1190-2006. Calibration and verification for hourly time step was done for period 1998-1999. The stream routing parameters were calibrated for flood event in years 1998 and 2007 and than verification for flood event in 1990. Discharge routing data analysis shown that possible inundation of Ljubljana and Savinja valley was not properly estimated. The flood areas are protected with levees and water does not spread over flooded areas in events used for calibration. Inundated areas in Ljubljana valley and Savinja valley are protected by levees and model could not simulate properly inundation of PMF. We recalibrate parameters controlled inundation on those areas for the worst scenario. Calculated PMF values drop down tramendosly after recalibration.

Brilly, Mitja; Vidmar, Andrej; Raj, Mojca Å.

2010-05-01

389

Maximum Correntropy Criterion for Robust Face Recognition.  

PubMed

In this paper, we present a sparse correntropy framework for computing robust sparse representations of face images for recognition. Compared with the state-of-the-art $l^1$-norm based sparse representation classifier (SRC), which assumes that noise also has a sparse representation, our sparse algorithm is developed based on the maximum correntropy criterion, which is much more insensitive to outliers. In order to develop a more tractable and practical approach, we in particular impose non-negativity constraint on the variables in the maximum correntropy criterion, and develop a half-quadratic optimization technique to approximately maximize the objective function in an alternating way, so that the complex optimization problem is reduced to learning a sparse representation through a weighted linear least squares problem with non-negativity constraint at each iteration. Our extensive experiments demonstrate that the proposed method is more robust and efficient in dealing with the occlusion and corruption problems in face recognition, as compared to the related state-of-the-art methods. In particular, it shows that the proposed method can improve both recognition accuracy and receiver operator characteristic (ROC) curves, while the computational cost is much lower than the SRC algorithms. PMID:21135440

He, Ran; Zheng, Wei-Shi; Hu, Bao-Gang

2010-11-30

390

Risk evaluation and management to reaching a suggested FSO in a steam meal.  

PubMed

Steam meals are ready-to-eat meals composed of raw and semi-cooked ingredients, which get cooked while microwave heating. In this study, an Indian style meal was selected, Chicken Tandoori, from two different producers. These meals were first evaluated with the Risk Ranger® to identify the main foodborne pathogens risks, which were Listeria monocytogenes, Salmonella Typhimurium and Bacillus cereus. Thereafter, quantitative microbiology was applied using different models and verified with growth and inactivation challenge tests. It was observed that the gamma model and the ComBase program® showed very similar results. However, in some cases the results obtained with the challenge tests showed different results. The information gathered was used to create different scenarios which indicate how to manage the risks by setting Performance Objectives during the different stages of the food chain of this product and hence reaching a suggested Food Safety Objective. PMID:21511122

Mejia, Z Sosa; Beumer, R R; Zwietering, M H

2011-06-01

391

Higher harmonics increase LISA's mass reach for supermassive black holes  

SciTech Connect

Current expectations on the signal-to-noise ratios and masses of supermassive black holes which the Laser Interferometer Space Antenna (LISA) can observe are based on using in matched filtering only the dominant harmonic of the inspiral waveform at twice the orbital frequency. Other harmonics will affect the signal-to-noise ratio of systems currently believed to be observable by LISA. More significantly, inclusion of other harmonics in our matched filters would mean that more massive systems that were previously thought to be not visible in LISA should be detectable with reasonable SNRs. Our estimates show that we should be able to significantly increase the mass reach of LISA and observe the more commonly occurring supermassive black holes of masses {approx}10{sup 8}M{sub {center_dot}}. More specifically, with the inclusion of all known harmonics LISA will be able to observe even supermassive black hole coalescences with total mass {approx}10{sup 8}M{sub {center_dot}}(10{sup 9}M{sub {center_dot}}) (and mass ratio 0.1) for a low frequency cutoff of 10{sup -4} Hz (10{sup -5} Hz) with an SNR up to {approx}60 ({approx}30) at a distance of 3 Gpc. This is important from the astrophysical viewpoint since observational evidence for the existence of black holes in this mass range is quite strong and binaries containing such supermassive black holes will be inaccessible to LISA if one uses as detection templates only the dominant harmonic.

Arun, K. G. [Raman Research Institute, Bangalore, 560 080 (India); LAL, Univ Paris-Sud, IN2P3/CNRS, Orsay (France); GRECO, Institut d'Astrophysique de Paris-C.N.R.S., Paris (France); Iyer, Bala R. [Raman Research Institute, Bangalore, 560 080 (India); Sathyaprakash, B. S. [School of Physics and Astronomy, Cardiff University, 5, The Parade, Cardiff, United Kingdom, CF24 3YB (United Kingdom); Sinha, Siddhartha [Raman Research Institute, Bangalore, 560 080 (India); Deptartment of Physics, Indian Institute of Science, Bangalore, 560 012 (India)

2007-06-15

392

Scientists Provide Perspectives as Drilling Reaches Subglacial Antarctic Lake Vostok  

NASA Astrophysics Data System (ADS)

Culminating decades of effort, researchers drilled to subglacial Lake Vostok on 5 February. The glacial drilling team of the 57th Russian Antarctic Expedition penetrated to the waters of the lake at a depth of 3769.3 meters through deep ice borehole 5G, according to a report sent to the Arctic and Antarctic Research Institute by the head of Vostok station and the head of the glacial drilling team. Researchers collected about 1.5 cubic meters of water while working to prevent contamination of the lake before a plug of frozen water sealed the lake again, as researchers had planned. The accomplishment culminates decades of effort to reach Lake Vostok—a freshwater lake roughly the size of Lake Ontario located near the middle of the continent—and it opens up a new era in investigating subglacial Antarctic lakes. Some scientists speculate that Lake Vostok, the largest of more than 280 known subglacial lakes on the continent, could harbor life forms in an environment that has been sealed off from light and air for possibly tens of millions of years. They also speculate that the Vostok environment could be analogous to that of some icy moons in the solar system.

Showstack, Randy

2012-02-01

393

Advanced REACH Tool (ART): calibration of the mechanistic model.  

PubMed

The mechanistic model of the Advanced Reach Tool (ART) provides a relative ranking of exposure levels from different scenarios. The objectives of the calibration described in this paper are threefold: to study whether the mechanistic model scores are accurately ranked in relation to exposure measurements; to enable the mechanistic model to estimate actual exposure levels rather than relative scores; and to provide a method of quantifying model uncertainty. Stringent data quality guidelines were applied to the collated data. Linear mixed effects models were used to evaluate the association between relative ART model scores and measurements. A random scenario and company component of variance were introduced to reflect the model uncertainty. Stratified analyses were conducted for different forms of exposure (abrasive dust, dust, vapours and mists). In total more than 2000 good quality measurements were available for the calibration of the mechanistic model. The calibration showed that after calibration the mechanistic model of ART was able to estimate geometric mean (GM) exposure levels with 90% confidence for a given scenario to lie within a factor between two and six of the measured GM depending upon the form of exposure. PMID:21403945

Schinkel, Jody; Warren, Nicholas; Fransman, Wouter; van Tongeren, Martie; McDonnell, Patricia; Voogd, Eef; Cherrie, John W; Tischer, Martin; Kromhout, Hans; Tielemans, Erik

2011-05-01

394

Advanced REACH Tool: A Bayesian Model for Occupational Exposure Assessment.  

PubMed

This paper describes a Bayesian model for the assessment of inhalation exposures in an occupational setting; the methodology underpins a freely available web-based application for exposure assessment, the Advanced REACH Tool (ART). The ART is a higher tier exposure tool that combines disparate sources of information within a Bayesian statistical framework. The information is obtained from expert knowledge expressed in a calibrated mechanistic model of exposure assessment, data on inter- and intra-individual variability in exposures from the literature, and context-specific exposure measurements. The ART provides central estimates and credible intervals for different percentiles of the exposure distribution, for full-shift and long-term average exposures. The ART can produce exposure estimates in the absence of measurements, but the precision of the estimates improves as more data become available. The methodology presented in this paper is able to utilize partially analogous data, a novel approach designed to make efficient use of a sparsely populated measurement database although some additional research is still required before practical implementation. The methodology is demonstrated using two worked examples: an exposure to copper pyrithione in the spraying of antifouling paints and an exposure to ethyl acetate in shoe repair. PMID:24665110

McNally, Kevin; Warren, Nicholas; Fransman, Wouter; Entink, Rinke Klein; Schinkel, Jody; van Tongeren, Martie; Cherrie, John W; Kromhout, Hans; Schneider, Thomas; Tielemans, Erik

2014-06-01

395

Has the Arctic Perennial Ice Cover Reached the Tipping Point?  

NASA Astrophysics Data System (ADS)

Analysis of satellite data from 1979 to the present has indicated that the Arctic perennial ice cover has been declining at a rapid rate of about 10 percent per decade. The yearly fluctuation was relatively large during the first 20 years but in the last decade, the extent and area of the perennial ice cover have been persistently low. The coverage was a record low in 2002, followed by a slight recovery in 2003 and 2004, another record low in 2005 and a mild recovery in 2006. During the summer of 2007, however, the rate of decline was phenomenal. The extent and area of the ice cover as of 4 September 2007 were 4.5 and 3.9 million square km, respectively, which are considerably less (by 18 to 22 percent) than those of 2005, the corresponding values of which are 5.5 and 5.0 million square km. The large decline suggests that the tipping point for the perennial ice has been reached and a recovery is no longer possible in the foreseeable future. Such hypothesis is supported by studies of the impact of ice-albedo feedback using satellite observed (and in situ) changes in SST (sea surface temperature) in conjunction with a thermodynamic model.

Comiso, J. C.

2007-12-01

396

Advanced REACH Tool: A Bayesian Model for Occupational Exposure Assessment  

PubMed Central

This paper describes a Bayesian model for the assessment of inhalation exposures in an occupational setting; the methodology underpins a freely available web-based application for exposure assessment, the Advanced REACH Tool (ART). The ART is a higher tier exposure tool that combines disparate sources of information within a Bayesian statistical framework. The information is obtained from expert knowledge expressed in a calibrated mechanistic model of exposure assessment, data on inter- and intra-individual variability in exposures from the literature, and context-specific exposure measurements. The ART provides central estimates and credible intervals for different percentiles of the exposure distribution, for full-shift and long-term average exposures. The ART can produce exposure estimates in the absence of measurements, but the precision of the estimates improves as more data become available. The methodology presented in this paper is able to utilize partially analogous data, a novel approach designed to make efficient use of a sparsely populated measurement database although some additional research is still required before practical implementation. The methodology is demonstrated using two worked examples: an exposure to copper pyrithione in the spraying of antifouling paints and an exposure to ethyl acetate in shoe repair.

McNally, Kevin; Warren, Nicholas; Fransman, Wouter; Entink, Rinke Klein; Schinkel, Jody; van Tongeren, Martie; Cherrie, John W.; Kromhout, Hans; Schneider, Thomas; Tielemans, Erik

2014-01-01

397

Reaching Out: The Bachelor of Arts Degree In Physics  

NASA Astrophysics Data System (ADS)

Physics degrees are not only for physicists. Our department believes that it would be healthy if attorneys, physicians, journalists, politicians, businesspeople, and others had undergraduate degrees in physics. Thus, we have begun offering a Bachelor of Arts degree in physics, for students who want to study physics as a background for other fields such as law (patents, environmental law), medical school, business (high-tech firms), journalism (science reporting, environmental reporting), music (accoustics, electronic music), and essentially any other profession. The program reaches outward, outside of physics, rather than pointing toward further work in physics. It begins with the algebra-based introductory course rather than the calculus-based course for future physicists and engineers. Two new courses are being created to provide these pre-professional students with broad science literacy and knowledge of physics-related technologies. The program is more flexible and less technical than the traditional Bachelor of Science program, allowing students time for outside electives and professional requirements in other fields.

Hobson, Art

1996-05-01

398

40 CFR 35.2205 - Maximum allowable project cost.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Maximum allowable project cost. 35.2205 Section 35.2205...35.2205 Maximum allowable project cost. (a) Grants awarded on or...regulation, the maximum allowable project cost will be the sum of: (1)...

2010-07-01

399

40 CFR 35.2205 - Maximum allowable project cost.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Maximum allowable project cost. 35.2205 Section 35.2205...35.2205 Maximum allowable project cost. (a) Grants awarded on or...regulation, the maximum allowable project cost will be the sum of: (1)...

2012-07-01

400

40 CFR 35.2205 - Maximum allowable project cost.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Maximum allowable project cost. 35.2205 Section 35.2205...35.2205 Maximum allowable project cost. (a) Grants awarded on or...regulation, the maximum allowable project cost will be the sum of: (1)...

2011-07-01

401

40 CFR 35.2205 - Maximum allowable project cost.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Maximum allowable project cost. 35.2205 Section 35.2205...35.2205 Maximum allowable project cost. (a) Grants awarded on or...regulation, the maximum allowable project cost will be the sum of: (1)...

2013-07-01

402

33 CFR 183.35 - Maximum weight capacity: Outboard boats.  

Code of Federal Regulations, 2010 CFR

...false Maximum weight capacity: Outboard boats. 183.35 Section 183.35 Navigation...SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading...35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity...

2010-07-01

403

49 CFR 230.24 - Maximum allowable stress.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Maximum allowable stress. 230.24 Section 230.24 Transportation...STANDARDS Boilers and Appurtenances Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value....

2011-10-01

404

49 CFR 230.24 - Maximum allowable stress.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Maximum allowable stress. 230.24 Section 230.24 Transportation...STANDARDS Boilers and Appurtenances Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value....

2012-10-01

405

40 CFR 141.13 - Maximum contaminant levels for turbidity.  

Code of Federal Regulations, 2010 CFR

... false Maximum contaminant levels for turbidity. 141.13 Section 141.13 Protection...141.13 Maximum contaminant levels for turbidity. The maximum contaminant levels for turbidity are applicable to both community...

2010-07-01

406

49 CFR 230.24 - Maximum allowable stress.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Maximum allowable stress. 230.24 Section 230.24 Transportation...STANDARDS Boilers and Appurtenances Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value....

2010-10-01

407

49 CFR 230.24 - Maximum allowable stress.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Maximum allowable stress. 230.24 Section 230.24 Transportation...STANDARDS Boilers and Appurtenances Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value....

2013-10-01

408

49 CFR 230.24 - Maximum allowable stress.  

Code of Federal Regulations, 2010 CFR

... 2009-10-01 false Maximum allowable stress. 230.24 Section 230.24 Transportation...STANDARDS Boilers and Appurtenances Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value....

2009-10-01

409

Long-reach 10-Gb/s RSOA-based WDM PON employing QPSK signal and coherent receiver.  

PubMed

We demonstrate a long-reach wavelength-division-multiplexed passive optical network (WDM PON) operating at the symmetric rate of 10.3 Gb/s. For the cost-effectiveness, we realize the upstream transmission by utilizing directly-modulated TO-can packaged reflective semiconductor optical amplifiers (RSOAs) and digital coherent receivers. In addition, to overcome the limited modulation bandwidth of this TO-can packaged RSOA (~2.2 GHz) and operate it at 10.3 Gb/s, we utilize the quadrature phase shift keying (QPSK) format and the electronic phase equalization technique. The result shows that we can extend the maximum reach of the 10.3-Gb/s RSOA-based WDM PON to ~80 km without using any remote amplifiers. PMID:22772232

Cho, K Y; Hong, U H; Jung, S P; Takushima, Y; Agata, A; Sano, T; Horiuchi, Y; Suzuki, M; Chung, Y C

2012-07-01

410

An approximate, maximum terminal velocity descent to a point  

SciTech Connect

No closed form control solution exists for maximizing the terminal velocity of a hypersonic glider at an arbitrary point. As an alternative, this study uses neighboring extremal theory to provide a sampled data feedback law to guide the vehicle to a constrained ground range and altitude. The guidance algorithm is divided into two parts: 1) computation of a nominal, approximate, maximum terminal velocity trajectory to a constrained final altitude and computation of the resulting unconstrained groundrange, and 2) computation of the neighboring extremal control perturbation at the sample value of flight path angle to compensate for changes in the approximate physical model and enable the vehicle to reach the on-board computed groundrange. The trajectories are characterized by glide and dive flight to the target to minimize the time spent in the denser parts of the atmosphere. The proposed on-line scheme successfully brings the final altitude and range constraints together, as well as compensates for differences in flight model, atmosphere, and aerodynamics at the expense of guidance update computation time. Comparison with an independent, parameter optimization solution for the terminal velocity is excellent. 6 refs., 3 figs.

Eisler, G.R.; Hull, D.G.

1987-01-01

411

The 1988 Solar Maximum Mission event list  

NASA Technical Reports Server (NTRS)

Information on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1988 pointed observations is presented. Data from the following SMM experiments are included: (1) gamma ray spectrometer; (2) hard x ray burst spectrometer; (3) flat crystal spectrometers; (4) bent crystal spectrometer; (5) ultraviolet spectrometer polarimeter; and (6) coronagraph/polarimeter. Correlative optical, radio, and Geostationary Operational Environmental Satellite (GOES) x ray data are also presented. Where possible, bursts, or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observation. Spacecraft pointing coordinates and flare site angular displacement values from sun center are also included.

Dennis, B. R.; Licata, J. P.; Tolbert, A. K.

1992-01-01

412

The Maximum Age of Trapezium Systems  

NASA Astrophysics Data System (ADS)

We sought to determine the maximum age of Trapezium systems by studying possible trapezium systems that were selected independently of their occurrence in H II regions. We started with the unpublished catalog by Allen, Tapia, & Parrao of all the known visual systems having three or more stars in which the maximum separation is less than 3.0 times the minimum separation. Their catalog has 968 such systems whose most frequent primary type is F, which does not describe young systems. With a CCD on the Kitt Peak 0.9 m telescope we obtained UBV frames for 265 systems accessible with our equipment on Kitt Peak. The frames were used to obtain UBV photometry for about 1500 stars with an accuracy of +/-0.04 mag between V=7 and 14 mag. Also these frames were used to obtain astrometry with an accuracy of +/-0.015d in position angle and +/-0.01" in separation. For the brightest star in each system we obtained a spectral type to determine the distance and reddening to the system. The measures were used to determine physical membership from stars that (1) fit a single color-magnitude diagram, (2) fit a common color-color diagram, and (3) show no astrometric motion compared to visual measures made (mostly) a century ago. Combining the results with spectroscopic data for 20 additional Allen et al. systems by Abt, we found that 126 systems had only optical companions to the primaries, 116 systems contained only a single physical pair, 13 were hierarchical systems with 3-6 members and having separation ratios of more than a factor of 10, two were small clusters, and only 28 fitted the criteria of Trapezium systems. However, as shown by Ambartsumian, about 9% of the hierarchical systems should appear to be Trapezium systems in projection. Those, like other hierarchical systems, have a broad distribution of primary spectral types. We isolated 14 systems that seem to be true Trapezium systems. They have primary types of B3 or earlier, indicating a maximum age of about 5×107 yr. This upper limit is consistent with the estimate made by Allen & Poveda for an age of several million years for these dynamically unstable systems. These Trapezia are also large with a median radius of 0.2 pc and a maximum radius of 2.6 pc. We asked why the sample of 285 possible Trapezium systems yielded only 14 true ones, despite the attempt made by Allen et al. to eliminate optical companions with a ``1% filter,'' i.e., demanding that each companion have less than a 1% chance of being a field star of that magnitude within a circle of its radius from the primary. The explanation seems to be that the double star catalogs are based mostly on BD magnitudes that, fainter than V=12 mag, are systematically too faint by 1 mag.

Abt, Helmut A.; Corbally, Christopher J.

2000-10-01

413

The 1980 solar maximum mission event listing  

NASA Technical Reports Server (NTRS)

Information is contained on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1980 pointed observations. Data from the following SMM experiments are included: (1) Gamma Ray Spectrometer, (2) Hard X-Ray Burst Spectrometer, (3) Hard X-Ray Imaging Spectrometer, (4) Flat Crystal Spectrometer, (5) Bent Crystal Spectrometer, (6) Ultraviolet Spectrometer and Polarimeter, and (7) Coronagraph/Polarimeter. Correlative optical, radio, and Geostationary Operational Environmental Satellite (GOES) x ray data are also presented. Where possible, bursts or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observations. Spacecraft pointing coordinates and flare site angular displacement values from Sun center are also included.

Speich, D. M.; Nelson, J. J.; Licata, J. P.; Tolbert, A. K.

1991-01-01

414

Genetic algorithm for maximum entropy image restoration  

NASA Astrophysics Data System (ADS)

Linear image restoration techniques induce erroneous detail around sharp intensity changes. Thus, considerable work has centered on nonlinear methods, which incorporate constraints to reduce the artifacts generated in the restoration. In our paper, we examine the applicability of genetic algorithms to solving optimization problems posed by nonlinear image recovery techniques, particularly by maximum entropy restoration. Each point in the solution space is a feasible image, with the pixels as decision variables. Search is multiobjective: the entropy of the estimate must be maximized, subject to constraints dependent on the observed data and image degradation model. We use Pareto techniques to achieve this combined requirement, and problem-oriented knowledge to direct the search. Typical issues for genetic algorithms are addressed: chromosomal representation, genetic operators, selection scheme, and initialization.

Toma, Cristian E.; Datcu, Mihai P.

1994-06-01

415

The 1989 Solar Maximum Mission event list  

NASA Technical Reports Server (NTRS)

This document contains information on solar burst and transient activity observed by the Solar Maximum Mission (SMM) during 1989 pointed observations. Data from the following SMM experiments are included: (1) Gamma Ray Spectrometer, (2) Hard X-Ray Burst Spectrometer, (3) Flat Crystal Spectrometer, (4) Bent Crystal Spectrometer, (5) Ultraviolet Spectrometer Polarimeter, and (6) Coronagraph/Polarimeter. Correlative optical, radio, and Geostationary Operational Satellite (GOES) X-ray data are also presented. Where possible, bursts or transients observed in the various wavelengths were grouped into discrete flare events identified by unique event numbers. Each event carries a qualifier denoting the quality or completeness of the observations. Spacecraft pointing coordinates and flare site angular displacement values from sun center are also included.

Dennis, B. R.; Licata, J. P.; Tolbert, A. K.

1992-01-01

416

Maximum power flux of auroral kilometric radiation  

NASA Astrophysics Data System (ADS)

Distant observations of intense auroral kilometric radiation (AKR) are discussed in light of the increased maximum AKR power flux registered by the 3D radio-mapping instrument on ISEE 3. Only AKR events that contain the highest frequency signals are selected, and during spacecraft rotation the spacecraft antenna gain is employed to increase the dynamic range of the instrument. The technique is found to result in the screening of false signals created by instrument overloading as well as the detection of genuine second-harmonic AKR signals while the spacecraft was 17 R(E) from earth. A very strong power flux of fundamental AKR is also reported, exceeding 3 x 10 to the -13th W/sq m/Hz at 360 kHz. The most intense source-region values detected by Isis I and Viking measurements are compared to the strong signal, and the signal is concluded to be the combined signal of a number of sources.

Benson, Robert F.; Fainberg, Joseph

1991-08-01

417

Maximum neighborhood margin discriminant projection for classification.  

PubMed

We develop a novel maximum neighborhood margin discriminant projection (MNMDP) technique for dimensionality reduction of high-dimensional data. It utilizes both the local information and class information to model the intraclass and interclass neighborhood scatters. By maximizing the margin between intraclass and interclass neighborhoods of all points, MNMDP cannot only detect the true intrinsic manifold structure of the data but also strengthen the pattern discrimination among different classes. To verify the classification performance of the proposed MNMDP, it is applied to the PolyU HRF and FKP databases, the AR face database, and the UCI Musk database, in comparison with the competing methods such as PCA and LDA. The experimental results demonstrate the effectiveness of our MNMDP in pattern classification. PMID:24701144

Gou, Jianping; Zhan, Yongzhao; Wan, Min; Shen, Xiangjun; Chen, Jinfu; Du, Lan

2014-01-01

418

Approximate maximum likelihood decoding of block codes  

NASA Technical Reports Server (NTRS)

Approximate maximum likelihood decoding algorithms, based upon selecting a small set of candidate code words with the aid of the estimated probability of error of each received symbol, can give performance close to optimum with a reasonable amount of computation. By combining the best features of various algorithms and taking care to perform each step as efficiently as possible, a decoding scheme was developed which can decode codes which have better performance than those presently in use and yet not require an unreasonable amount of computation. The discussion of the details and tradeoffs of presently known efficient optimum and near optimum decoding algorithms leads, naturally, to the one which embodies the best features of all of them.

Greenberger, H. J.

1979-01-01

419

Maximum Neighborhood Margin Discriminant Projection for Classification  

PubMed Central

We develop a novel maximum neighborhood margin discriminant projection (MNMDP) technique for dimensionality reduction of high-dimensional data. It utilizes both the local information and class information to model the intraclass and interclass neighborhood scatters. By maximizing the margin between intraclass and interclass neighborhoods of all points, MNMDP cannot only detect the true intrinsic manifold structure of the data but also strengthen the pattern discrimination among different classes. To verify the classification performance of the proposed MNMDP, it is applied to the PolyU HRF and FKP databases, the AR face database, and the UCI Musk database, in comparison with the competing methods such as PCA and LDA. The experimental results demonstrate the effectiveness of our MNMDP in pattern classification.

Zhan, Yongzhao; Shen, Xiangjun; Du, Lan

2014-01-01

420

Maximum magnitude in the Lower Rhine Graben  

NASA Astrophysics Data System (ADS)

Estimating Mmax, the assumed magnitude of the largest future earthquakes expected on a fault or in an area, involves large uncertainties. No theoretical basis exists to infer Mmax because even where we know the long-term rate of motion across a plate boundary fault, or the deformation rate across an intraplate zone, neither predict how strain will be released. As a result, quite different estimates can be made based on the assumptions used. All one can say with certainty is that Mmax is at least as large as the largest earthquake in the available record. However, because catalogs are often short relative to the average recurrence time of large earthquakes, larger earthquakes than anticipated often occur. Estimating Mmax is especially challenging within plates, where deformation rates are poorly constrained, large earthquakes are rarer and variable in space and time, and often occur on previously unrecognized faults. We explore this issue for the Lower Rhine Graben seismic zone where the largest known earthquake, the 1756 Düren earthquake, has magnitude 5.7 and should occur on average about every 400 years. However, paleoseismic studies suggest that earthquakes with magnitudes up to 6.7 occurred during the Late Pleistocene and Holocene. What to assume for Mmax is crucial for critical facilities like nuclear power plants that should be designed to withstand the maximum shaking in 10,000 years. Using the observed earthquake frequency-magnitude data, we generate synthetic earthquake histories, and sample them over shorter intervals corresponding to the real catalog's completeness. The maximum magnitudes appearing most often in the simulations tend to be those of earthquakes with mean recurrence time equal to the catalog length. Because catalogs are often short relative to the average recurrence time of large earthquakes, we expect larger earthquakes than observed to date to occur. In a next step, we will compute hazard maps for different return periods based on the synthetic catalogs, in order to determine the influence of underestimating Mmax.

Vanneste, Kris; Merino, Miguel; Stein, Seth; Vleminckx, Bart; Brooks, Eddie; Camelbeeck, Thierry

2014-05-01

421

Technology Transfer, Reaching the Market for Geopressured-Geothermal Resources  

SciTech Connect

Technology transfer to the industrial sector for geopressured-geothermal technology has included diverse strategies, with successes and obstacles or roadblocks. Numerical data are tabulated in terms of response to the various strategies. Strategy categories include the following: feasibility studies and reports, consortium activities and proceedings, the Geothermal Resource Council, national and international meetings of the American Association of Petroleum Geologists, other societal and organizational meetings, and conferences, Department of Energy solicitation of interest in the Commerce Business Daily, industry peer review panels, and the Secretary's Technology Initiative. Additionally, the potential of a 12-page color brochure on the geopressured-geothermal resource, workshops, and cooperative research and development agreement (CRADA) is discussed. In conclusion, what is the best way to reach the market and what is the winning combination? All of the above strategies contribute to technology transfer and are needed in some combination for the desired success. The most successful strategy activities for bringing in the interest of the largest number of industries and the independents are the consortium meetings, one-on-one telephone calling, and consortium proceedings with information service followup. the most successful strategy activities for bringing in the interest and participation of ''majors'' are national and international peer reviewed papers at internationally recognized industry-related society meetings, and on-call presentations to specific companies. Why? Because quality is insured, major filtering has already taken place, and the integrity of the showcase is established. Thus, the focused strategy is reduced to a target of numbers (general public/minors/independents) versus quality (majors). The numerical results of the activities reflecting four years of technology transfer following the 15 year lead in the early phases of geopressured-geothermal program under the leadership of Dr. Myron Dorfman, reflect a dynamic surveying of what works in technology transfer with industry in the area of geopressured-geothermal resources. The identified obstacles can be removed and future efforts can benefit by this cataloging and discussion of results.

Wys, J. Negus-de

1992-03-24

422

Is the full potential of the biopharmaceutics classification system reached?  

PubMed

In this paper we analyse how the biopharmaceutics classification system (BCS) has been used to date. A survey of the literature resulted in a compilation of 242 compounds for which BCS classes were reported. Of these, 183 compounds had been reported to belong to one specific BCS class whereas 59 compounds had been assigned to multiple BCS classes in different papers. Interestingly, a majority of the BCS class 2 compounds had fraction absorbed (FA) values >85%, indicating that they were completely absorbed after oral administration. Solubility was computationally predicted at pH 6.8 for BCS class 2 compounds to explore the impact of the pH of the small intestine, where most of the absorption occurs, on the solubility. In addition, the solubilization capacity of lipid aggregates naturally present in the intestine was studied computationally and experimentally for a subset of 12 compounds. It was found that all acidic compounds with FA>85% were completely dissolved in the pH of the small intestine. Further, lipids at the concentration used in fasted state simulated intestinal fluid (FaSSIF) dissolved the complete dose given of the most lipophilic (logD6.5>3) compounds studied. Overall, biorelevant dissolution media (pure buffer of intestinal pH or FaSSIF) identified that for 20 of the 29 BCS class 2 compounds with FA>85% the complete dose given orally would be dissolved. These results indicate that a more relevant pH restriction for acids and/or dissolution medium with lipids present better forecast solubility-limited absorption in vivo than the presently used BCS solubility criterion. The analysis presented herein further strengthens the discussion on the requirement of more physiologically relevant dissolution media for the in vitro solubility classification performed to reach the full potential of the BCS. PMID:24075971

Bergström, Christel A S; Andersson, Sara B E; Fagerberg, Jonas H; Ragnarsson, Gert; Lindahl, Anders

2014-06-16

423

Estimating mean body masses of marine mammals from maximum body lengths  

Microsoft Academic Search

Generalized survival models were applied to growth curves published for 17 species of cetaceans (5 mysticetes, 12 odontocetes) and 13 species of pinnipeds (1 odobenid, 4 otariids, 8 phocids). The mean mass of all individuals in the population was calculated and plotted against the maximum body length reported for each species. The data showed strong linearity (on logarithmic scales), with

Andrew W. Trites; Daniel Pauly

1998-01-01

424

A Fast Algorithm to Compute Maximum Likelihood Estimates for the Hypergeometric Software Reliability Model  

Microsoft Academic Search

We present a fast and exact algorithm to com- pute maximum likelihood estimates for the number of faults initially contained in a software, using the hypergeometric software reliability model. The algo- rithm is based on a rigorous mathematical analysis of the growth behavior of the likelihood function for the model. We also clarify the stochastic process under- lying the model

Frank Padberg

2001-01-01

425

Stepwise advancement versus maximum jumping with headgear activator.  

PubMed

The aim of this study was to compare the effects of stepwise mandibular advancement versus maximum jumping and extended treatment versus early retention. The material was obtained prospectively and consisted of lateral cephalograms taken at the start (T0), after initial (T1), and at the end (T2) of treatment, from two groups of consecutively treated skeletal Class II patients who had undergone therapy with headgear activators. The first headgear activator group, HGA-S (n=24; mean age 11.9 +/- 1.2 years), was treated for 13 months and had 4-mm mandibular advancement every 3 months. The second headgear activator group, HGA-M (n=31; mean age 11.2 +/- 1.5 years), had maximum jumping, 6-8 mm interincisal opening, for a total of 15.4 months, and with reduced wear for the last 6.9 months. The dropout over 12 months was 41 and 46 per cent, respectively. Pre-treatment growth changes were obtained as a reference. An independent t-test was used to determine differences in baseline dentofacial morphology between the groups, a paired t-test for intra-group comparisons, and an independent t-test to evaluate differences between the groups. The results, in both groups, showed enhanced mandibular prognathism during the initial phase (T0-T1), followed by normal growth (T1-T2), and lower face height enhancement throughout treatment (T0-T2). For both groups, the mandibular plane and occlusal angle increased, possibly enhanced by 'extrusion' of the lower molars. For both groups, maxillary forward growth was restrained only during the initial phase, but the effect remained significant at T2 for the HGA-S group. In the HGA-M group, the lower incisors were protruded, while in the HGA-S group, they were unaffected. The findings indicate that both modes of mandibular jumping resulted in skeletal and dental effects. The length of active treatment seemed to be decisive in maintaining the treatment effects; stepwise advancement had less dental effects. PMID:17556729

Wey, Mang Chek; Bendeus, Margareta; Peng, Li; Hägg, Urban; Rabie, A Bakr M; Robinson, Wayne

2007-06-01

426

High force reaching task induces widespread inflammation, increased spinal cord neurochemicals and neuropathic pain.  

PubMed

Repetitive strain injuries (RSI), which include several musculoskeletal disorders and nerve compression injuries, are associated with performance of repetitive and forceful tasks. In this study, we examined in young, adult Sprague-Dawley rats, the effects of performing a voluntary, moderate repetition, high force (MRHF; nine reaches/min; 60% maximum pulling force) task for 12 weeks on motor behavior and nerve function, inflammatory responses in forearm musculoskeletal and nerve tissues and serum, and neurochemical immunoexpression in cervical spinal cord dorsal horns. We observed no change in reach rate, but reduced voluntary participation and grip strength in week 12, and increased cutaneous sensitivity in weeks 6 and 12, the latter indicative of mechanical allodynia. Nerve conduction velocity (NCV) decreased 15% in the median nerve in week 12, indicative of low-grade nerve compression. ED-1 cells increased in distal radius and ulna in week 12, and in the median nerve and forearm muscles and tendons in weeks 6 and 12. Cytokines IL-1alpha, IL-1beta, TNF-alpha, and IL-10 increased in distal forearm bones in week 12, while IL-6 increased in tendon in week 12. However, serum analysis revealed only increased TNF-alpha in week 6 and macrophage inflammatory protein 3a (MIP3a) in weeks 6 and 12. Lastly, Substance P and neurokinin-1 were both increased in weeks 6 and 12 in the dorsal horns of cervical spinal cord segments. These results show that a high force, but moderate repetition task, induced declines in motor and nerve function as well as peripheral and systemic inflammatory responses (albeit the latter was mild). The peripheral inflammatory responses were associated with signs of central sensitization (mechanical allodynia and increased neurochemicals in spinal cord dorsal horns). PMID:19032977

Elliott, M B; Barr, A E; Clark, B D; Amin, M; Amin, S; Barbe, M F

2009-01-23

427

High force reaching task induces widespread inflammation, increased spinal cord neurochemicals and neuropathic pain  

PubMed Central

Repetitive strain injuries (RSI), which include several musculoskeletal disorders and nerve compression injuries, are associated with performance of repetitive and forceful tasks. In this study, we examined the effects of performing a voluntary, moderate repetition, high force (MRHF; 9 reaches/min; 60% maximum pulling force) task for 12 weeks on motor behavior and nerve function, inflammatory responses in forearm musculoskeletal and nerve tissues and serum, and neurochemical immunoexpression in cervical spinal cord dorsal horns. We observed no change in reach rate, but reduced voluntary participation and grip strength in week 12, and increased cutaneous sensitivity in weeks 6 and 12, the latter indicative of mechanical allodynia. Nerve conduction velocity (NCV) decreased 15% in the median nerve in week 12, indicative of low-grade nerve compression. ED-1 cells increased in distal radius and ulna in week 12, and in the median nerve and forearm muscles and tendons in weeks 6 and 12. Cytokines IL-1?, IL-1?, TNF-?, and IL-10 increased in distal forearm bones in week 12, while IL-6 increased in tendon in week 12. However, serum analysis revealed only increased TNF-? in week 6 and macrophage inflammatory protein 3a (MIP3a) in weeks 6 and 12. Lastly, Substance P and neurokinin-1 were both increased in weeks 6 and 12 in the dorsal horns of cervical spinal cord segments. These results show that a high force, but moderate repetition task, induced declines in motor and nerve function as well as peripheral and systemic inflammatory responses (albeit the latter was mild). The peripheral inflammatory responses were associated with signs of central sensitization (mechanical allodynia and increased neurochemicals in spinal cord dorsal horns).

Elliott, Melanie B.; Barr, Ann E.; Clark, Brian D.; Amin, Mamta; Amin, Shreya; Barbe, Mary F.

2009-01-01

428

Effect of speed manipulation on the control of aperture closure during reach-to-grasp movements  

PubMed Central

This study investigates coordination between hand transport and grasp movement components by examining a hypothesis that the hand location, relative to the object, in which aperture closure is initiated remains relatively constant under a wide range of transport speed. Subjects made reach-to-grasp movements to a dowel under four speed conditions: slow, comfortable, fast but comfortable, and maximum (i.e., as fast as possible). The distance traveled by the wrist after aperture reached its maximum (aperture closure distance) increased with an increase of transport speed across the speed conditions. This finding rejected the hypothesis and suggests that the speed of hand transport is taken into account in aperture closure initiation. Within each speed condition, however, the closure distance exhibited relatively small variability across trials, even though the total distance traveled by the wrist during the entire transport movement varied from trial to trial. The observed stability in aperture closure distance across trials implies that the hand distance to the object plays an important role in the control law governing the initiation of aperture closure. Further analysis showed that the aperture closure distance depended on the amplitude of peak aperture as well as hand velocity and acceleration. To clarify the form of the above control law, we analyzed four different mathematical models, in which a decision to initiate grasp closure is made as soon as a specific movement parameter (wrist distance to target or transport time) crosses a threshold that is either a constant value or a function of the above-mentioned other movement-related parameters. Statistical analysis performed across all movement conditions revealed that the control law model (according to which grasp initiation is made when hand distance to target becomes less than a certain linear function of aperture amplitude, hand velocity, and hand acceleration) produced significantly smaller residual errors than the other three models. The findings support the notion that transport–grasp coordination and grasp initiation is based predominantly on spatial characteristics of the arm movement, rather than movement timing.

Squire, Linda M.; Stelmach, George E.

2007-01-01

429

Application of multi-objective technique in modeling water and sediment flow in river reaches  

NASA Astrophysics Data System (ADS)

Usually water resources problems consist of multiple objectives that may be conflicting and competing in nature. To evaluate optimal water resources system performances often it is required to obtain a compromise solution satisfying several goals and objectives. For example, in the case of multipurpose reservoir operations, a number of conflicting and competing purposes such as supply of water for conservation uses, downstream flood control, hydropower generation and related environmental objectives are to be optimally satisfied. It may be noted that for deriving maximum benefit from conservation uses reservoir storage should be as high as possible; on the other hand to achieve maximum flood control benefits the storage should be kept as low as possible. Since flood control and conservation objectives are conflicting in nature, higher achievement in flood control objective results in lower attainment of the conservation objectives. In other areas of water resources such as, rainfall runoff modeling, water quality problems, watershed management etc often a number of objectives are required to be satisfied to derive optimal system performances. It is known that one prominent cause of soil erosion and runoff generation from a catchment is related to the effect of rainfall over the catchment and thus water and the sediment discharge at a river station are mainly depended on rainfall and the catchment characteristics. Water and sediment discharge for a river section can be considered as two outputs due to a rainfall input over the catchment. To describe sediment and water flow through river reaches usually separate models are used and the model parameters are estimated using single/multiple optimization routines. Since water and sediment flow are effects with a common cause, a new model can be obtained that can quantify and explain both the effects that is, flow of sediment and water in a river course. In the present study, application of multiple objective optimization technique has described in obtaining parameters of the integrated water-sediment flow model. The integrated model needs to be calibrated using both water and sediment data for a river reach and requires separate objective functions to independently match water and sediment flow variations for a station. The integrated model describing two hydrological variables is highly nonlinear with exponential model form and requires efficient algorithm to identify model parameters. Multiple objectives were framed to calibrate the model using water and sediment data and the model parameters were estimated applying non-dominated sorting genetic algorithm (NSGA-II). The proposed model formulations are demonstrated for simulating suspended sediment load and water discharge in the Mississippi River Basin, USA. Results obtained show that an integrated model having multiple objectives can be developed to describe two hydrological variables with satisfactory performances.

Sil, Briti Sundar; Choudhury, Parthasarathi

2010-10-01

430

Predictive Reaching for Occluded Objects by 6-Month-Old Infants  

Microsoft Academic Search

Infants were presented with an object that moved into reaching space on a path that was either continuously visible or interrupted by an occluder. Infants' reaching was reduced sharply when an occluder was present, even though the occluder itself was out of reach and did not serve as a barrier to direct reaching for the object. We account for these

Elizabeth S. Spelke; Claes von Hofsten

2001-01-01

431

Occlusion Is Hard: Comparing Predictive Reaching for Visible and Hidden Objects in Infants and Adults  

Microsoft Academic Search

Infants can anticipate the future location of a moving object and execute a predictive reach to intercept the object. When a moving object is temporarily hidden by darkness or occlusion, 6-month- old infants' reaching is perturbed, but performance on darkness trials is significantly better than occlusion trials. How does this reaching behavior change over development? Experiment 1 tested predictive reaching

Susan Hespos; Gustaf Gredeback; Claes von Hofsten; Elizabeth S. Spelked

432

Economic interpretation of environmental flow regime downstream diverted river reaches.  

NASA Astrophysics Data System (ADS)

Water demand for hydropower production is increasing together with the consciousness of the importance of riparian ecosystems and biodiversity. Some Cantons in Switzerland and other alpine regions in Austria and in Sud Tirol (Italy) started replacing the inadequate concept of Minimum Flow Requirement (MFR) with a dynamic one, by releasing a fix percentage of the total inflow (e.g. 25 %) to the environment. In the same direction Perona et al. (in revision) mathematically formulated a method particularly suitable for small hydropower plants, handling the environment as a non-traditional water use, which competes with exploitators. This model uses the Principle of Equal Marginal Utility (PEMU) as optimal water allocation rule for generating like-natural flow releases while maximizing the aggregate economic benefit of all uses (Gorla and Perona, in revision). In this paper we show how redistribution policies can be interpreted in terms of PEMU, particularly we focus at traditional water repartition rules, such as the MFR, but also to dynamic ones like proportional redistribution. For the first case we show both ecological and economical arguments suggesting its inappropriateness; in the second case we highlight explicit points of strength and weakness, and suggest ways of improvement. For example the flow release allocation rule can be changed from inflow-independent ones (e.g., proportional redistribution), to inflow-dependent ones (e.g., non-proportional). The latters, having fewer constraints, can generally lead to better both ecological and economical performances. A class of simple functions, based on the PEMU, is then proposed as a suitable solution in run-of-river or small hydropower plants. Each water repartition policy underlies an ecosystem monetization. We explicit the value of the ecosystem health underlying each policy by means of the PEMU under a few assumptions, and discuss how the theoretic efficient redistribution law obtained by our approach is feasible and doesn't imply high costs or advanced management tools. Our approach is a simple but effective step towards eco-sustainability in the growing market of mini hydropower plants, where operation rules like MFR are still widespread. As such, this method is a powerful instrument for political managers to explicit contradictions thus enlightening best compromise measures/decisions. References Perona, P., Characklis, G., Duerrenmatt, D.J., in revision. Inverse parameters estimation of simple riparian benefit economical models. Journal of Environmental Management . Gorla, L. and Perona, P., in revision. On quantifying ecologically sustainable flow releases in a diverted river reach. Journal of Hydrology.

Gorla, Lorenzo; Perona, Paolo

2013-04-01

433

Non-induced cyclic hydroxamic acids in wheat during juvenile stage of growth  

Microsoft Academic Search

2,4-Dihydroxy-1,4-benzoxazine-3-one glucoside (DIBOA-G) and its methoxy analogue, 2,4-dihydroxy-7-methoxy-1,4-benzoxazine-3-one glucoside (DIMBOA-G), were present in germinating wheat (Triticum aestivum); the corresponding aglycones, DIBOA and DIMBOA, appeared soon after germination. The amounts of these compounds reached a maximum 12–48 hours after germination, and then decreased to undetectable levels as the plants began autotrophic growth. The time of their appearance was little affected by

Eri Nakagawa; Takashi Amano; Nobuhiro Hirai; Hajime Iwamura

1995-01-01

434

Stimulation of protein phosphatase activity by insulin and growth factors in 3T3 cells  

SciTech Connect

Incubation of Swiss mouse 3T3-D1 cells with physiological concentrations of insulin resulted in a rapid and transient activation of protein phosphatase activity as measure by using ({sup 32}P)phosphorylase {alpha} as substrate. Activation reached a maximum level (140% of control value) within 5 min of addition and returned to control levels within 20 min. The effect of insulin was dose-dependent with half-maximal activation occurring at {approx}5 nM insulin. This activity could be completely inhibited by addition of the heat-stable protein inhibitor 2, which suggests the presence of an activated type-1 phosphatase. Similar effects on phosphatase activity were seen when epidermal growth factor and platelet-derived growth factor were tested. These results suggest that some of the intracellular effects caused by insulin and growth factors are mediated through the activation of a protein phosphatase.

Chan, C.P.; McNall, S.J.; Krebs, E.G.; Fischer, E.H. (Univ. of Washington, Seattle (USA))

1988-09-01

435

[Effects of climate change on potato growth in semi-arid region of Loess Plateau, China].  

PubMed

Based on the 1988-2008 located observation and 2007-2008 encrypted observation of potato growth and the 1957-2008 meteorological observation in semi-arid region of Loess Plateau, this paper studied the effects of climate change on the potato growth in this region. In 1957-2008, the annual precipitation in this region had a descending trend, with a linear fitting rate of the annual precipitation change curves being - 13.359 mm x (10 a)(-1), while the annual mean temperature displayed an ascending trend, with a linear fitting rate of the annual mean temperature change curves being 0.239 degrees C x (10 a)(-1). During potato growth period, the aridity index displayed a marked ascending trend, and the linear fitting rate of the aridity index change curves was 0.102 x (10 a)(-1). The growth rate of potato tuber became faster from the 96th day after sowing, reached the maximum on the 110th day, and turned slower from the 124th day. The interval from sowing to seedling emergence was shortened by 1-2 d x (10 a)(-1), and that from inflorescence formation to reaping and of whole growth period was lengthened by 9-10 d x (10 a) (-1). In the study region, climate warming shortened the vegetative growth stage, but lengthened the reproductive growth stage and whole growth period of potato. PMID:20462009

Yao, Yu-Bi; Wang, Run-Yuan; Deng, Zhen-Yong; Han, Shu-Lin; Xing, Tuo-Qin

2010-02-01

436

Unsteady-state transfer of impurities during crystal growth of sucrose in sugarcane solutions  

NASA Astrophysics Data System (ADS)

In this work, we present growth rate data of sucrose crystals in the presence of impurities that can be used by both sugar technologists and crystal growth scientists. Growth rate curves measured in a pilot-scale evaporative crystallizer suggest a period of slow growth that follows the seeding of crystals into supersaturated technical solutions. The observed trend was enhanced by adding typical sugarcane impurities such as starch, fructose or dextran to the industrial syrups. Maximum growth rates of sucrose resulted at intermediate rather than high supersaturation levels in the presence of the additives. The effects of the additives on the sucrose solubility and sucrose mass transfer in solution were taken into account to explain the observed crystal growth kinetics. A novel mechanism was identified of unsteady-state adsorption of impurities at the crystal surface and their gradual replacement by the crystallizing solute towards the equilibrium occupation of the active sites for growth. Specifically designed crystallization experiments at controlled supersaturation confirmed this mechanism by showing increasing crystal growth rates with time until reaching a steady-state value for a given supersaturation level and impurity content.

Martins, P. M.; Ferreira, A.; Polanco, S.; Rocha, F.; Damas, A. M.; Rein, P.

2009-07-01

437

Land Cover Changes and Sediment Connectivity in a Torrential Reach of the Central Spanish Pyrenees  

NASA Astrophysics Data System (ADS)

The Ijuez River drains a sector of the Eocene flysch in the southern Pyrenees, The basin includes natural forests and afforestations in the montane belt, as well as extensive grasslands in the subalpine belt, over 1700 m a.s.l. At the beginning, the streambed develops a narrow canyon with a very steep longitudinal profile that ends in a torrential alluvial plain plenty of cobbles and boulders arranged in a chaotic manner. Several check dams in the middle and lower stretches of the river have contributed to reduce sediment transfer downstream. The upper reach, however, maintains it torrential character. There, the Ijuez River shows the occurrence of various changes in the hydromorphological regime: (i) a terrace level above 3 m of the actual channel, with matrix-supported cobbles indicating a fluvio-torrential regime; (ii) above the terrace level the accumulation of a large number of debris flows occurred; (iii) recently a strong incision of the actual channel occurred, contributing to the dismantlement of fluvial terrace and debris flow deposits. This evolution reflects, most likely, the changes underwent in the subalpine and montane belts due to deforestation and the consequent transformation of the forests into cultivated fields (below 1600 m a.s.l.) and subalpine grasslands to feed the transhumant sheep flocks. Such changes occurred between 2500-2000 years ago and between 1200-900 year ago, according to the deforestation ages obtained from charcoal remnants in soils and lacustrine sediments. Radiocarbon dates obtained for debris flows (from woody remnants located within the debris-flow deposits) in the Ijuez basin indicate an age of approximately 100 years ago, coinciding with the moment of maximum population pressure and the maximum extent of the cultivated area. Along the 20th century, farmland abandonment, afforestations and natural reforestation, as well as the decline of the livestock pressure has reduced sediment yield and connectivity, thus explaining the recent reduction in sediment supply and the consequent channel incision.

San Juan, Yasmina; María García Ruiz, José; Gómez Villar, Amelia; Nadal Romero, Estela; Beguería, Santiago; Álvarez Martínez, Javier; Arnáez Vadillo, Jose; González Sampériz, Penélope; Serrano Muela, María Pilar; Galilea Salvador, Ianire

2014-05-01

438

Reaching extended length-scales with temperature-accelerated dynamics  

NASA Astrophysics Data System (ADS)

In temperature-accelerated dynamics (TAD) a high-temperature molecular dynamics (MD) simulation is used to accelerate the search for the next low-temperature activated event. While TAD has been quite successful in extending the time-scales of simulations of non-equilibrium processes, due to the fact that the computational work scales approximately as the cube of the number of atoms, until recently only simulations of relatively small systems have been carried out. Recently, we have shown that by combining spatial decomposition with our synchronous sublattice algorithm, significantly improved scaling is possible. However, in this approach the size of activated events is limited by the processor size while the dynamics is not exact. Here we discuss progress in developing an alternate approach in which high-temperature parallel MD along with localized saddle-point (LSAD) calculations, are used to carry out TAD simulations without restricting the size of activated events while keeping the dynamics ``exact'' within the context of harmonic transition-state theory. In tests of our LSAD method applied to Ag/Ag(100) annealing and Cu/Cu(100) growth simulations