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1

Improvements in perception of maximum reaching height transfer to increases or decreases in reaching ability.  

PubMed

Perception of affordances for a given behavior reflects not only a person's current action capabilities but also impending changes to his or her action capabilities. This experiment investigated perception of affordances for reaching when the means of performing the reaching task would increase or decrease reaching ability. The results showed that in both cases perception of maximum reaching height reflected the person's anthropometric properties (i.e., standing height) and the future means of reaching, and improvements in perception of maximum reaching height transferred to unpracticed reaching tasks. The results highlight the role of action in the perception of affordances and are discussed in the context of a description of perceptual systems as smart perceptual devices. PMID:25588270

Wagman, Jeffrey B; Taheny, Craig A; Higuchi, Takahiro

2014-01-01

2

Anthropometric modelling for the determination of 3-D maximum functional reach  

Microsoft Academic Search

Maximum functional reach for 3-D industrial workspace was determined from selected structural body dimensions. Six structural body dimensions out of 19 measured in this study were found to be dominant and statistically related to the functional reach in the spectrum of the workspace. Next to arm length, the most dominant body dimension was popliteal height for the male and stature

Devendra N. Behara; Biman Das

2011-01-01

3

Analysis of maximum reach in WDM PON architecture based on distributed Raman amplification and pump recycling technique.  

PubMed

We analyze the performance of bidirectional WDM PON architecture which utilizes distributed Raman amplification and pump recycling technique. The maximum reach at data rates of 622 Mb/s and 1.25 Gb/s in the proposed WDM PON architecture is calculated by taking into account the effects of power budget, chromatic dispersion of transmission fiber, and Raman amplification-induced noises with a given amount of Raman pump power. From the result, the maximum reach for 622 Mb/s and 1.25 Gb/s signal transmission is calculated to be 65 km and 60 km with a Raman pump power of 700 mW, respectively. We also find that the calculated results agree well with the experimental results which were reported previously. PMID:19550773

Kim, Chul Han; Lee, Ju Han; Lee, Kwanil

2007-10-29

4

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

5

Growth and maximum size of tiger sharks (Galeocerdo cuvier) in Hawaii.  

PubMed

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13'17?N 109°52'14?W), in the southern Gulf of California (minimum distance between tag and recapture sites ?=? approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates. PMID:24416287

Meyer, Carl G; O'Malley, Joseph M; Papastamatiou, Yannis P; Dale, Jonathan J; Hutchinson, Melanie R; Anderson, James M; Royer, Mark A; Holland, Kim N

2014-01-01

6

Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii  

PubMed Central

Tiger sharks (Galecerdo cuvier) are apex predators characterized by their broad diet, large size and rapid growth. Tiger shark maximum size is typically between 380 & 450 cm Total Length (TL), with a few individuals reaching 550 cm TL, but the maximum size of tiger sharks in Hawaii waters remains uncertain. A previous study suggested tiger sharks grow rather slowly in Hawaii compared to other regions, but this may have been an artifact of the method used to estimate growth (unvalidated vertebral ring counts) compounded by small sample size and narrow size range. Since 1993, the University of Hawaii has conducted a research program aimed at elucidating tiger shark biology, and to date 420 tiger sharks have been tagged and 50 recaptured. All recaptures were from Hawaii except a single shark recaptured off Isla Jacques Cousteau (24°13?17?N 109°52?14?W), in the southern Gulf of California (minimum distance between tag and recapture sites ?=? approximately 5,000 km), after 366 days at liberty (DAL). We used these empirical mark-recapture data to estimate growth rates and maximum size for tiger sharks in Hawaii. We found that tiger sharks in Hawaii grow twice as fast as previously thought, on average reaching 340 cm TL by age 5, and attaining a maximum size of 403 cm TL. Our model indicates the fastest growing individuals attain 400 cm TL by age 5, and the largest reach a maximum size of 444 cm TL. The largest shark captured during our study was 464 cm TL but individuals >450 cm TL were extremely rare (0.005% of sharks captured). We conclude that tiger shark growth rates and maximum sizes in Hawaii are generally consistent with those in other regions, and hypothesize that a broad diet may help them to achieve this rapid growth by maximizing prey consumption rates. PMID:24416287

Meyer, Carl G.; O'Malley, Joseph M.; Papastamatiou, Yannis P.; Dale, Jonathan J.; Hutchinson, Melanie R.; Anderson, James M.; Royer, Mark A.; Holland, Kim N.

2014-01-01

7

Coarsening Foams Robustly Reach a Self-Similar Growth Regime  

NASA Astrophysics Data System (ADS)

Dry liquid foams coarsen like other diphasic systems governed by interfacial energy: gas slowly diffuses across liquid films, resulting in large bubbles growing at the expense of smaller ones which eventually shrink and disappear. A foam scatters light very effectively, preventing direct optical observation of bubble sizes and shapes in large foams. Using high speed x-ray tomography, we have produced 4D movies (i.e., 3D+time) of up to 30 000 bubbles. After a transient regime, the successive images look alike, except that the average bubble size increases as the square root of time: This scaling state is the long sought self-similar growth regime. The bubble size and face-number distributions in this regime are compared with experimental distributions for grains in crystals and with numerical simulations of foams.

Lambert, Jérôme; Mokso, Rajmund; Cantat, Isabelle; Cloetens, Peter; Glazier, James A.; Graner, François; Delannay, Renaud

2010-06-01

8

The number e^{(1/2)} is the ratio between the time of maximum value and the time of maximum growth rate for restricted growth phenomena?  

E-print Network

For many natural process of growth, with the growth rate independent of size due to Gibrat law and with the growth process following a log-normal distribution, the ratio between the time (D) for maximum value and the time (L) for maximum growth rate (inflexion point) is then equal to the square root of the base of the natural logarithm (e^{1/2}). On the logarithm scale this ratio becomes one half ((1/2)). It remains an open question, due to lack of complete data for various cases with restricted growth, whether this e^{1/2} ratio can be stated as e^{1/2}-Law. Two established examples already published, one for an epidemic spreading and one for droplet production, support however this ratio. Another example appears to be the height of humain body. For boys the maximum height occurs near 23 years old while the maximum growth rate is at the age near 14, and there ratio is close to e^{1/2}. The main theoretical base to obtain this conclusion is problem independent, provided the growth process is restricted, such as public intervention to control the spreading of communicable epidemics, so that an entropy is associated with the process and the role of dissipation, representing the mechanism of intervention, is maximized. Under this formulation the principle of maximum rate of entropy production is used to make the production process problem independent.

Zi-Niu Wu

2013-10-02

9

Impact of seed source power on dispersion-limited maximum reach in WDM-PONs using broadband light source seeded optical sources.  

PubMed

The maximum reach in a WDM-PON using a broadband light source (BLS) seeded optical source has been experimentally evaluated by taking into account both effects of dispersion-induced pulse broadening and excess intensity noise (EIN) increase. In order to investigate the impact of BLS seed source power on the dispersion-limited performance, the system's performance has been measured and compared as a function of the spectrum-sliced BLS seed power into a reflective semiconductor optical amplifier (RSOA). From the results, we confirmed that the maximum reach in a RSOA based WDM-PON was mainly degraded by the dispersion-induced EIN increase. Therefore, by mitigating the effect of dispersion-induced EIN increase with a high seed power into a RSOA, the maximum reach in the WDM-PON using a BLS seeded RSOA source could be achieved to be ~60 km of single-mode fiber at the spectrum-sliced BLS seed power of >-10 dBm and a 1.25 Gb/s signal without using any dispersion-compensating techniques. PMID:22418106

Kim, Chul Han

2012-02-13

10

Effects of lag and maximum growth in contaminant transport and biodegradation modeling  

SciTech Connect

The effects of time lag and maximum microbial growth on biodegradation in contaminant transport are discussed. A mathematical model is formulated that accounts for these effects, and a numerical case study is presented that demonstrates how lag influences biodegradation.

Wood, B.D. (Pacific Northwest Lab., Richland, WA (United States)); Dawson, C.N. (Rice Univ., Houston, TX (United States). Dept. of Mathematical Sciences)

1992-06-01

11

Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii  

E-print Network

Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii Carl G. Meyer1 *, Joseph M. O , Mark A. Royer1 , Kim N. Holland1 1 Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Honolulu, Hawai'i, United States of America, 2 National Marine Fisheries Service, Pacific Islands Fisheries

12

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

13

Persistent growth of CO2 emissions and implications for reaching climate targets  

NASA Astrophysics Data System (ADS)

Efforts to limit climate change below a given temperature level require that global emissions of CO2 cumulated over time remain below a limited quota. This quota varies depending on the temperature level, the desired probability of staying below this level and the contributions of other gases. In spite of this restriction, global emissions of CO2 from fossil fuel combustion and cement production have continued to grow by 2.5% per year on average over the past decade. Two thirds of the CO2 emission quota consistent with a 2 °C temperature limit has already been used, and the total quota will likely be exhausted in a further 30 years at the 2014 emissions rates. We show that CO2 emissions track the high end of the latest generation of emissions scenarios, due to lower than anticipated carbon intensity improvements of emerging economies and higher global gross domestic product growth. In the absence of more stringent mitigation, these trends are set to continue and further reduce the remaining quota until the onset of a potential new climate agreement in 2020. Breaking current emission trends in the short term is key to retaining credible climate targets within a rapidly diminishing emission quota.

Friedlingstein, P.; Andrew, R. M.; Rogelj, J.; Peters, G. P.; Canadell, J. G.; Knutti, R.; Luderer, G.; Raupach, M. R.; Schaeffer, M.; van Vuuren, D. P.; Le Quéré, C.

2014-10-01

14

Secular trends for takeoff and maximum adolescent growth for eight decades of Japanese cohort data.  

PubMed

The presence of secular trends in the onset or takeoff of the adolescent growth spurt and subsequent adolescent growth of Japanese boys and girls were investigated using data published in "The Statistical Report of the School Health Survey" by the Ministry of Education, Science, Sports and Culture, Japan. An optimum kernel regression method was used to derive the biological parameters of the adolescent growth curve. An increasing trend in height at takeoff (i.e., height at the onset of the adolescent growth spurt) and height at peak height velocity (PHV) among Japanese children was evident during the 8 decades covered in this study. Age at PHV (i.e., the timing of the maximum adolescent growth) for each sex has decreased. Age at takeoff (i.e., the timing of the onset of the adolescent growth spurt) has decreased in boys during this century, but was almost constant in girls at about 7.8 years of age. Moreover, the interval between age at takeoff and age at PHV in girls has gradually decreased over this century. Since the birth year 1915, velocity at takeoff for girls was markedly greater than that for boys, whereas peak height velocity for girls was significantly less than that for boys (P < 0.05). Am. J. Hum. Biol. 12:702-712, 2000. Copyright 2000 Wiley-Liss, Inc. PMID:11534063

Ali, Md. Ayub; Lestrel, Pete E.; Ohtsuki, Fumio

2000-09-01

15

Hitting times and the running maximum of Markovian growth-collapse processes  

Microsoft Academic Search

We consider the level hitting times\\u000a?y<\\/sub> = inf{t ? 0 | Xt<\\/sub> = y}\\u000aand the running maximum process\\u000aMt<\\/sub> = sup{Xs<\\/sub> | 0 ? s ? t}\\u000aof a growth-collapse process\\u000a(Xt<\\/sub>)t?0<\\/sub>, defined as a\\u000a[0, ?)-valued Markov process that grows linearly between random\\u000a`collapse' times at which downward jumps with state-dependent distributions\\u000aoccur. We show how the

Andreas Löpker; Wolfgang Stadjey

2011-01-01

16

The estimation of maximum growth rate for aluminium nitride crystals grown by direct sublimation  

NASA Astrophysics Data System (ADS)

The largest crystals if AIN reported have been grown by direct sublimation and this paper examines each step in the sublimation process. It is shown that the large energy (9.8 eV) required for homogeneous dissociation of N 2 precludes any contribution from the transport of atomic nitrogen. The steps considered in the evaporation direction are: (1)AIN (s) ? Al ads + N ads, (2) Al ads ? Al (s), (3)N ads ? {1}/{2}N 2ads ? {1}/{2}N 2(g) or N ads ? N (g) ? {1}/{2}N 2(g). The likely rate-limiting step is identified and simple kinetic theory used to estimate the maximum possible rate of material transport in sublimation. The sticking coefficient of N 2 has been obtained from the data of Hoch and Ramakrishnan on the nitrogen exchange reaction of AIN. Choice of useful growth temperature is shown to be restricted to the range 2000-2400°C, where maximum possible growth rates range from 0.1-4 ? {m}/{s}.

Dryburgh, P. M.

1992-11-01

17

Ammonia inhibition of the maximum growth rate (? m ) of hydrogenotrophic methanogens at various pH-levels and temperatures  

Microsoft Academic Search

A method for the quantitative measurement of the maximum growth rate (µm) of hydrogen-consuming methanogenic populations was applied to assess the toxicity of ammonia1 under various pH and temperature conditions. The maximum uninhibited growth rate of the hydrogenotrophic population present in sludge from an industrial anaerobic wastewater treatment system appeared to be 0.126 h-1 at pH=7 and 37°C. At 350

Iman W. Koster; Ernst Koomen

1988-01-01

18

Effect of intercropping Panicum maximum var. Ntchisi and Lablab purpureus on the growth, herbage yield and chemical composition of Panicum maximum var. Ntchisi at different harvesting times.  

PubMed

The study was conducted to evaluate the effect of intercropping Panicum maximum var. Ntchisi and Lablab purpureus on the growth, herbage yield and chemical composition of P. maximum var. Ntchisi at different harvesting times at the Teaching and Research farm, Federal University of Agriculture, Abeokuta in a randomized complete block design. Samples were collected at different harvesting times (8, 10, 12, 14 weeks after planting). The growth parameters which were plant height, leaf length, leaf number and tiller number measured showed that the intercropping of grass with legume were higher than in the sole plot of P. maximum var. Ntchisi. The plant yield was consistently higher (p < 0.05) in intercropped forages than in sole throughout the harvesting times. The crude protein contents of the forages were also higher for the intercropped across the treatments. The values of the fibre components were significantly different (p < 0.05) at different harvesting times and it was increasing as the harvesting time was increasing. From this study, considering the herbage yield and chemical composition of intecropping Panicum maximum var. Ntchisi and Lablab purpureus, they can be grazed by ruminant animals or harvested at 12 weeks after planting when the quality and quantity will support livestock productivity and can be conserved to be fed to ruminant animals during dry season when feed availability and quality are extremely low. PMID:24511710

Ojo, V O A; Dele, P A; Amole, T A; Anele, U Y; Adeoye, S A; Hassan, O A; Olanite, J A; Idowu, O J

2013-11-15

19

Pigmentation in Drosophila melanogaster reaches its maximum in Ethiopia and correlates most strongly with ultra-violet radiation in sub-Saharan Africa  

PubMed Central

Background Pigmentation has a long history of investigation in evolutionary biology. In Drosophila melanogaster, latitudinal and altitudinal clines have been found but their underlying causes remain unclear. Moreover, most studies were conducted on cosmopolitan populations which have a relatively low level of genetic structure and diversity compared to sub-Saharan African populations. We investigated: 1) the correlation between pigmentation traits within and between the thorax and the fourth abdominal segment, and 2) their associations with different geographical and ecological variables, using 710 lines belonging to 30 sub-Saharan and cosmopolitan populations. Results Pigmentation clines substantially differed between sub-Saharan and cosmopolitan populations. While positive correlations with latitude have previously been described in Europe, India and Australia, in agreement with Bogert's rule or the thermal melanism hypothesis, we found a significant negative correlation in Africa. This correlation persisted even after correction for altitude, which in its turn showed a positive correlation with pigmentation independently from latitude. More importantly, we found that thoracic pigmentation reaches its maximal values in this species in high-altitude populations of Ethiopia (1,600-3,100 m). Ethiopian flies have a diffuse wide thoracic trident making the mesonotum and the head almost black, a phenotype that is absent from all other sub-Saharan or cosmopolitan populations including high-altitude flies from Peru (~3,400 m). Ecological analyses indicated that the variable most predictive of pigmentation in Africa, especially for the thorax, was ultra-violet (UV) intensity, consistent with the so-called Gloger's rule invoking a role of melanin in UV protection. Conclusion Our data suggest that different environmental factors may shape clinal variation in tropical and temperate regions, and may lead to the evolution of different degrees of melanism in different high altitude populations in the tropics. PMID:25115161

2014-01-01

20

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. PMID:23741488

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

2013-01-01

21

Ion permeability of the cytoplasmic membrane limits the maximum growth temperature of bacteria and archaea  

Microsoft Academic Search

Protons and sodium ions are the most commonly used coupling ions in energy transduction in bacteria and archaea. At their growth temperature, the permeability of the cytoplasmic membrane of thermophilic bacteria to protons is high compared with that of sodium ions. In some thermophiles, sodium is the sole energy-coupling ion. To test whether sodium is the preferred coupling ion at

Jack L. C. M. van de Vossenberg; Trees Ubbink-Kok; Marieke G. L. Elferink; Arnold J. M. Driessen; Wil N. Konings

1995-01-01

22

Maximum growth rates and possible life strategies of different bacterioplankton groups in relation to phosphorus availability in a freshwater reservoir.  

PubMed

We investigated net growth rates of distinct bacterioplankton groups and heterotrophic nanoflagellate (HNF) communities in relation to phosphorus availability by analysing eight in situ manipulation experiments, conducted between 1997 and 2003, in the canyon-shaped Rímov reservoir (Czech Republic). Water samples were size-fractionated and incubated in dialysis bags at the sampling site or transplanted into an area of the reservoir, which differed in phosphorus limitation (range of soluble reactive phosphorus concentrations--SRP, 0.7-96 microg l-1). Using five different rRNA-targeted oligonucleotide probes, net growth rates of the probe-defined bacterial groups and HNF assemblages were estimated and related to SRP using Monod kinetics, yielding growth rate constants specific for each bacterial group. We found highly significant differences among their maximum growth rates while insignificant differences were detected in the saturation constants. However, the latter constants represent only tentative estimates mainly due to insufficient sensitivity of the method used at low in situ SRP concentrations. Interestingly, in these same experiments HNF assemblages grew significantly faster than any bacterial group studied except for a small, but abundant cluster of Betaproteobacteria (targeted by the R-BT065 probe). Potential ecological implications of different growth capabilities for possible life strategies of different bacterial phylogenetic lineages are discussed. PMID:16913921

Simek, Karel; Hornák, Karel; Jezbera, Jan; Nedoma, Jirí; Vrba, Jaroslav; Straskrábová, Viera; Macek, Miroslav; Dolan, John R; Hahn, Martin W

2006-09-01

23

A Simple Approximate Result for the Maximum Growth Rate of Baroclinic Instabilities.  

NASA Astrophysics Data System (ADS)

The Charney problem for baroclinic instability involves the quasi-geostrophic instability of a zonal flow on a 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, for the most part, has precluded extracting simple results of some generality. In this note, it is shown that there does exist a 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. Moreover, the result extends to substantially more general profiles than those in the Charney problem.

Lindzen, R. S.; Farrell, Brian

1980-07-01

24

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

25

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

26

THE EFFECT OF PH ON MAXIMUM BACTERIAL GROWTH RATE AND ITS POSSIBLE ROLE AS A DETERMINANT OF BACTERIAL COMPETITION IN THE RUMEN  

Microsoft Academic Search

SUMMARY Five rumen bacteria were inoculated into media with pH values ranging from 6.7 to 4.7 to determine effects on maximum growth rate. Streptococcus boris, Bacteroides ruminicola, and Selenomanas ruminantium appeared to be more resistant to low pH than either Butyrivib- rio fibrisolvens or Megasphaera elsdenii. S. Boris, B. ruminicola, and S. ruminantium showed gradual decreases in maximum growth rate

J. B. Russell; W. M. Sharp; R. L. Baldwin

27

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

28

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...

29

On Some Growth Properties of Entire Functions Using Their Maximum Moduli Focusing (p, q)th Relative Order  

PubMed Central

We discuss some growth rates of composite entire functions on the basis of the definition of relative (p, q)th order (relative (p, q)th lower order) with respect to another entire function which improve some earlier results of Roy (2010) where p and q are any two positive integers.

Sanchez Ruiz, Luis Manuel; Datta, Sanjib Kumar; Biswas, Tanmay; Mondal, Golok Kumar

2014-01-01

30

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. PMID:22396738

Wang, Yafeng; ?ufar, Katarina; Eckstein, Dieter; Liang, Eryuan

2012-01-01

31

REACH. Electricity Units. Secondary.  

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 electricity. The instructional units focus on electricity fundamentals and electric motors. Each unit follows a typical format that includes a unit sheet,…

Smith, Gene; Sappe, Hoyt

32

REACH. Air Conditioning 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 air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

Garrison, Joe; And Others

33

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

34

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

35

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

36

GAP-REACH  

PubMed Central

Growing awareness of health and health care disparities highlights the importance of including information about race, ethnicity, and culture (REC) in health research. Reporting of REC factors in research publications, however, is notoriously imprecise and unsystematic. This article describes the development of a checklist to assess the comprehensiveness and the applicability of REC factor reporting in psychiatric research publications. The 16-itemGAP-REACH© checklist was developed through a rigorous process of expert consensus, empirical content analysis in a sample of publications (N = 1205), and interrater reliability (IRR) assessment (N = 30). The items assess each section in the conventional structure of a health research article. Data from the assessment may be considered on an item-by-item basis or as a total score ranging from 0% to 100%. The final checklist has excellent IRR (? = 0.91). The GAP-REACH may be used by multiple research stakeholders to assess the scope of REC reporting in a research article. PMID:24080673

Lewis-Fernández, Roberto; Raggio, Greer A.; Gorritz, Magdaliz; Duan, Naihua; Marcus, Sue; Cabassa, Leopoldo J.; Humensky, Jennifer; Becker, Anne E.; Alarcón, Renato D.; Oquendo, María A.; Hansen, Helena; Like, Robert C.; Weiss, Mitchell; Desai, Prakash N.; Jacobsen, Frederick M.; Foulks, Edward F.; Primm, Annelle; Lu, Francis; Kopelowicz, Alex; Hinton, Ladson; Hinton, Devon E.

2015-01-01

37

Pretoria Centre Reaches Out  

NASA Astrophysics Data System (ADS)

On 5 July 2014 six members of the Pretoria Centre of ASSA braved the light pollution of one of the shopping malls in Centurion to reach out to shoppers a la John Dobson and to show them the moon, Mars and Saturn. Although the centre hosts regular monthly public observing evenings, it was felt that we should take astronomy to the people rather than wait for the people to come to us.

Olivier, Bosman

2014-08-01

38

Effects of High-Flow Experiments from Glen Canyon Dam on Abundance, Growth, and Survival Rates of Early Life Stages of Rainbow Trout in the Lees Ferry Reach of the Colorado River  

USGS Publications Warehouse

High-flow experiments (HFEs) from Glen Canyon Dam are primarily intended to conserve fine sediment and improve habitat conditions for native fish in the Colorado River as it flows through Grand Canyon National Park, Arizona. These experimental flows also have the potential to affect the rainbow trout (Oncorhynchus mykiss) population in the Lees Ferry tailwater reach immediately below the dam, which supports a highly valued recreational fishery and likely influences the abundance of rainbow trout in Grand Canyon. Understanding how flow regimes affect the survival and growth of juvenile rainbow trout is critical to interpreting trends in adult abundance. This study reports on the effects of HFEs in 2004 and 2008 on early life stages of rainbow trout in the Lees Ferry reach on the basis of monthly sampling of redds (egg nests) and the abundance of the age-0 trout (fertilization to about 1 to 2 months from emergence) and their growth during a 7-year period between 2003 and 2009. Multiple lines of evidence indicate that the March 2008 HFE resulted in a large increase in early survival rates of age-0 trout because of an improvement in habitat conditions. A stock-recruitment analysis demonstrated that age-0 abundance in July 2008 was more than fourfold higher than expected, given the number of viable eggs that produced these fish. A hatch-date analysis showed that early survival rates were much higher for cohorts that hatched about 1 month after the 2008 HFE (about April 15, 2008) relative to those fish that hatched before this date. These cohorts, fertilized after the 2008 HFE, would have emerged into a benthic invertebrate community that had recovered, and was possibly enhanced by, the HFE. Interannual differences in growth of age-0 trout, determined on the basis of otolith microstructure, support this hypothesis. Growth rates in the summer and fall of 2008 (0.44 mm/day) were virtually the same as in 2006 (0.46 mm/day), the highest recorded during 6 years, even though abundance was eightfold greater in 2008. We speculate that the 60-hour-long 2008 HFE (with peak magnitude about twice that of the annual peak flow during the previous 4 years) increased interstitial spaces in the gravel bed substrate and food availability or quality, leading to higher early survival of recently emerged trout and better growth of these fish through summer and fall. Abundance in 2009 was more than twofold higher than expected, given the estimated number of viable eggs deposited in that year, perhaps indicating that the effect of the 2008 HFE on early life stages was somewhat persistent. In a 3-week interval that spanned the November 2004 HFE, abundance of age-0 trout that were approximately 7 months old from hatch experienced about a threefold decline, compared to the approximately twofold decrease observed between November and December 2008. Abundance of age-0 trout that were approximately 10 months old from hatch was very similar across sampling trips that spanned the March 2008 HFE. It is uncertain whether the decline in abundance after the November 2004 HFE was the result of higher flow-induced mortality or higher flow-induced downstream dispersal. A focused monitoring effort in Marble Canyon (the reach immediately downstream of the Lees Ferry tailwater) before and after future HFEs is recommended to resolve this uncertainty. Relatively detailed monitoring of early life stages-such as the program described in this study-is essential to establish linkages between Glen Canyon Dam operations, or possibly other factors, and trends in the abundance of important nonnative and native fish populations living downstream within Grand Canyon National Park.

Korman, Josh; Kaplinski, Matthew; Melis, Theodore S.

2010-01-01

39

Maximum Likelihood  

NSDL National Science Digital Library

This material introduces the basic theory of maximum likelihood estimation by discussing the likelihood function, the log likelihood function, and maximizing these functions using calculus. Several exercises ask students to derive certain estimators, while others have students compare the behavior of those estimators with other possibilities through the use of various JAVA applets. The applets use the same control features: the sliders set the parameter values, the Â?Stop #Â? drop down menu sets the number of samples taken, the Â?Update #Â? drop down menu sets how often the graph and tables update during the experiment, the single arrow takes one sample, the double arrow runs the full experiment, the square stops the experiment, and the back arrow resets the applet. This page is one lesson from the Virtual Laboratories in Statistics.

Siegrist, Kyle

40

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

41

Reaching Beyond The Stars  

NASA Astrophysics Data System (ADS)

Strawbridge Observatory at Haverford College is home to a undergraduate-led public observing program. Our program holds ~once monthly public events throughout the academic year that take advantage of eyepiece observing on our 16-inch and 12-inch telescopes as well as of the classroom, library, and projection system. These resources allow us to organize a variety of astronomy related activities that are engaging for individuals of all ages: accessible student talks, current film screenings and even arts and crafts for the families who attend with young children. These events aim to spark curiosity in others about scientific discovery and about the remarkable nature of the world in which we live. In addition to exciting local families about astronomy, this program has excited Haverford students from a range of disciplines about both science and education. Being entirely student led means that we are able to take the initiative in planning, coordinating and running all events, fostering an atmosphere of collaboration, experimentation and commitment amongst our volunteers. Additionally, this program is one of the few at Haverford that regularly reaches beyond the campus walls to promote and build relationships with the outside community. In light of this, our program presents a distinctive and enlightening opportunity for student volunteers: we get to use our scientific backgrounds to educate a general audience, while also learning from them about how to communicate and inspire in others the excitement we feel about the subject of astronomy. The work on this project has been supported by NSF AST-1151462.

Baker, Mariah; Rosenthal, L.; Gaughan, A.; Hopkins, E.

2014-01-01

42

Conservation reaches new heights.  

PubMed

The conservation program with the management assistance of the Woodlands Mountain Institute in 2 contiguous parks, the Mount Everest National Park in Nepal and the Qomolangma Nature Reserve in China, in 2 countries is described. The focus is on conservation of the complex ecosystem with sustainable development by showing local people how to benefit from the park without environmental damage. Cultural diversity is as important as biological diversity. The area has been designated by UNESCO as a World Heritage Site with the "last pure ecological seed" of the Himalayas. The regional geography and culture are presented. Population growth has impacted natural resources through overgrazing, cultivation of marginal land, and deforestation; future plans to build a dam and road bordering the nature reserve pose other threats. Proposed management plans for the Makalu-Barun Nature Park (established in November 1991) and Conservation Area include a division of the park into nature reserve areas free of human activity, protected areas which permit traditional land use, and special sites and trail for tourists and religious pilgrims. The conservation area will act as a buffer for the park and provide economic opportunities; further subdivisions include land use for biodiversity protection, community forest and pasture, agroforestry, and agriculture and settlement. Efforts will be made to increase the welfare of women and local people; proposed projects include the introduction of higher milk-producing animals for stall feeding. Also proposed is a cultural and natural history museum. 70% of the project's resources will be directed to local community participation in consultation and park maintenance. The project is a model of how conservation and protection of natural resources can coexist with local economic development and participation; an integration of preservation of biological diversity, mountain wisdom, and the value of local people as resources for conservation. PMID:12285834

Pepall, J; Khanal, P

1992-10-01

43

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

44

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

45

Fault growth by segment linkage: an explanation for scatter in maximum displacement and trace length data from the Canyonlands Grabens of SE Utah  

Microsoft Academic Search

Maximum displacement (D) and trace length (L) data for a population of 97 normal faults from the Canyonlands Grabens region of SE Utah are presented. Values of L range from 100 to 6500 m, and of D from 1.5–155 m. The data exhibit a scatter between D and L of about half an order-of-magnitude. This is comparable to that exhibited

Joseph A. Cartwright; Bruce D. Trudgill; Christopher S. Mansfield

1995-01-01

46

Effect of maximum-tolerated doses and low-dose metronomic chemotherapy on serum vascular endothelial growth factor and thrombospondin-1 levels in patients with advanced nonsmall cell lung cancer  

Microsoft Academic Search

Background  Angiogenesis is regulated by a balance of both angiogenic inducers and inhibitors. This study was designed to evaluate the\\u000a effect of both maximum-tolerated doses (MTD) and low-dose metronomic chemotherapy (LDM) on serum vascular endothelial growth\\u000a factor (VEGF), thrombospondin-1 (TSP1) and VEGFR1 concentrations in patients with advanced nonsmall cell lung cancer.\\u000a \\u000a \\u000a \\u000a Patients and methods  Forty consecutive patients with advanced stage nonsmall cell

Faruk Tas; Derya Duranyildiz; Hilal O. Soydinc; Irfan Cicin; Meltem Selam; Kazim Uygun; Rian Disci; Vildan Yasasever; Erkan Topuz

2008-01-01

47

PNW RIVER REACH FILE DOCUMENTATION  

EPA Science Inventory

The U.S. Geological Survey (USGS) in cooperation with Federal and state agencies, and NW Indian Tribes has produced a 1:100,000-scale River Reach data layer for the Pacific Northwest that will serve water-resource management applications for the next decade or more. The Pacific N...

48

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.

49

Astronomical reach of fundamental physics.  

PubMed

Using basic physical arguments, we derive by dimensional and physical analysis the characteristic masses and sizes of important objects in the universe in terms of just a few fundamental constants. This exercise illustrates the unifying power of physics and the profound connections between the small and the large in the cosmos we inhabit. We focus on the minimum and maximum masses of normal stars, the corresponding quantities for neutron stars, the maximum mass of a rocky planet, the maximum mass of a white dwarf, and the mass of a typical galaxy. To zeroth order, we show that all these masses can be expressed in terms of either the Planck mass or the Chandrasekar mass, in combination with various dimensionless quantities. With these examples, we expose the deep interrelationships imposed by nature between disparate realms of the universe and the amazing consequences of the unifying character of physical law. PMID:24477692

Burrows, Adam S; Ostriker, Jeremiah P

2014-02-18

50

Astronomical reach of fundamental physics  

PubMed Central

Using basic physical arguments, we derive by dimensional and physical analysis the characteristic masses and sizes of important objects in the universe in terms of just a few fundamental constants. This exercise illustrates the unifying power of physics and the profound connections between the small and the large in the cosmos we inhabit. We focus on the minimum and maximum masses of normal stars, the corresponding quantities for neutron stars, the maximum mass of a rocky planet, the maximum mass of a white dwarf, and the mass of a typical galaxy. To zeroth order, we show that all these masses can be expressed in terms of either the Planck mass or the Chandrasekar mass, in combination with various dimensionless quantities. With these examples, we expose the deep interrelationships imposed by nature between disparate realms of the universe and the amazing consequences of the unifying character of physical law. PMID:24477692

Burrows, Adam S.; Ostriker, Jeremiah P.

2014-01-01

51

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

52

Mirror versus parallel bimanual reaching  

PubMed Central

Background In spite of their importance to everyday function, tasks that require both hands to work together such as lifting and carrying large objects have not been well studied and the full potential of how new technology might facilitate recovery remains unknown. Methods To help identify the best modes for self-teleoperated bimanual training, we used an advanced haptic/graphic environment to compare several modes of practice. In a 2-by-2 study, we compared mirror vs. parallel reaching movements, and also compared veridical display to one that transforms the right hand’s cursor to the opposite side, reducing the area that the visual system has to monitor. Twenty healthy, right-handed subjects (5 in each group) practiced 200 movements. We hypothesized that parallel reaching movements would be the best performing, and attending to one visual area would reduce the task difficulty. Results The two-way comparison revealed that mirror movement times took an average 1.24 s longer to complete than parallel. Surprisingly, subjects’ movement times moving to one target (attending to one visual area) also took an average of 1.66 s longer than subjects moving to two targets. For both hands, there was also a significant interaction effect, revealing the lowest errors for parallel movements moving to two targets (p?reaching performance can be observed with parallel movements with a veridical display (moving to two separate targets). These results point to the expected levels of challenge for these bimanual training modes, which could be used to advise therapy choices in self-neurorehabilitation. PMID:23837908

2013-01-01

53

Accessible Buildings for People with Walking and Reaching Limitations.  

ERIC Educational Resources Information Center

Research was reviewed and conducted regarding the accessibility of buildings for physically disabled persons. Data was produced regarding anthropometrics (eye level and reach limits for ambulant, semiambulant, and wheelchair bound persons); wheelchair maneuvers; speed and distance (maximum travel distances for people with limitations of stamina);…

Steinfeld, Edward; And Others

54

Extending earthquakes' reach through cascading.  

PubMed

Earthquakes, whatever their size, can trigger other earthquakes. Mainshocks cause aftershocks to occur, which in turn activate their own local aftershock sequences, resulting in a cascade of triggering that extends the reach of the initial mainshock. A long-lasting difficulty is to determine which earthquakes are connected, either directly or indirectly. Here we show that this causal structure can be found probabilistically, with no a priori model nor parameterization. Large regional earthquakes are found to have a short direct influence in comparison to the overall aftershock sequence duration. Relative to these large mainshocks, small earthquakes collectively have a greater effect on triggering. Hence, cascade triggering is a key component in earthquake interactions. PMID:18292339

Marsan, David; Lengliné, Olivier

2008-02-22

55

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 Willem.

56

REACH Report to the Rockefeller Foundation. Revised.  

ERIC Educational Resources Information Center

This document summarizes the activities of REACH, the Rural Education Alliance for Collaborative Humanities. REACH is an effort to strengthen rural education in South Carolina through writing and the study of local history and culture. Among REACH projects are the REACH School Programs, fostering student created research on the history and…

Blodgett, Jack

57

Feeding a diet contaminated with ochratoxin A for chickens at the maximum level recommended by the EU for poultry feeds (0.1 mg/kg). 1. Effects on growth and slaughter performance, haematological and serum traits.  

PubMed

The European Commission Recommendation 2006/576/EC, suggests that the maximum level of Ochratoxin A (OTA) in poultry feeds should be set at 0.1 mg OTA/kg. Thirty-six one-day-old male Hubburd broiler chickens were divided into two groups, a Control (basal diet) and an Ochratoxin A (basal diet + 0.1 mg OTA/kg) group. The growth and slaughter performance traits were recorded. The liver, spleen, bursa of Fabricius and thymus weights were measured. The erythrocyte and leukocyte numbers were assayed in blood samples, and the heterophils to lymphocytes (H/L) ratio was determined. Alpha-1-acid glycoprotein (AGP), lysozyme, the total protein and the electrophoretic pattern were evaluated in serum samples. Liver enzymes (alanino aminotransferase, ALT and aspartate aminotransferase, AST) and kidney function parameters (uric acid and creatinine) were quantified. The results revealed that feeding a 0.1 mg OTA/kg contaminated diet to chicks caused a decrease in the absolute thymus weight (p < 0.05) and a lower total protein (p < 0.01), albumin (p < 0.01), alpha (p < 0.05), beta (p = 0.001) and gamma (p = 0.001) globulins serum concentration in the Ochratoxin A group. Moreover, the albumin-to-globulin (A/G) ratio of the OTA-treated animals resulted to be higher (p < 0.05). Feeding broiler chickens, a diet contaminated with the maximum level admitted by the European Commission Recommendation (0.1 mg OTA/kg), did not affect the animal performance, slaughter traits, organ weights, haematological parameters, liver enzyme or renal function parameters concentrations but had an overall immunosuppressant effect, with reduction in the thymus weight and of the total serum protein, albumin, alpha, beta and gamma globulins concentration. PMID:23639013

Pozzo, L; Salamano, G; Mellia, E; Gennero, M S; Doglione, L; Cavallarin, L; Tarantola, M; Forneris, G; Schiavone, A

2013-05-01

58

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

59

Maximum grasping reach of operators possessing functional impairments of the upper extremities  

E-print Network

Level Classification** Muscles Affected Cervical - 7 (C-7) Thoracic - 2 (T-2) Thoracic - 4 (T-4) Thoracic - 12 (T-12) Lumbar - 5 (L-5) Tri cepts, extensor di gi torum Intercostal (between ribs) Lateral hamstrings tibialis posterior, peroneals...

Goebel, Lucky Arlan

1978-01-01

60

Aptasensing of chloramphenicol in the presence of its analogues: reaching the maximum residue limit.  

PubMed

A novel, label-free folding induced aptamer-based electrochemical biosensor for the detection of chloramphenicol (CAP) in the presence of its analogues has been developed. CAP is a broad-spectrum antibiotic that has lost its favor due to its serious adverse toxic effects on human health. Aptamers are artificial nucleic acid ligands (ssDNA or RNA) able to specifically recognize a target such as CAP. In this article, the aptamers are fixed onto a gold electrode surface by a self-assembly approach. In the presence of CAP, the unfolded ssDNA on the electrode surface changes to a hairpin structure, bringing the target molecules close to the surface and triggering electron transfer. Detection limits were determined to be 1.6 × 10(-9) mol L(-1). In addition, thiamphenicol (TAP) and florfenicol (FF), antibiotics with a structure similar to CAP, did not influence the performance of the aptasensor, suggesting a good selectivity of the CAP-aptasensor. Its simplicity and low detection limit (because of the home-selected aptamers) suggest that the electrochemical aptasensor is suitable for practical use in the detection of CAP in milk samples. PMID:22725137

Pilehvar, Sanaz; Mehta, Jaytry; Dardenne, Freddy; Robbens, Johan; Blust, Ronny; De Wael, Karolien

2012-08-01

61

Nova M31 2014-11a has not reached its maximum yet  

NASA Astrophysics Data System (ADS)

We report an increased optical brightness of Nova M31 2014-11a (ATel #6675). Using the 50/70 cm Schmidt telescope at NAO Rozhen, Bulgaria, we obtained 3 consecutive 300s frames on Nov 10 and 5 consecutive 300s frames on Nov 11 in Cousins R filter.

Ovcharov, E.; Kurtenkov, A.; Valcheva, A.; Nedialkov, P.

2014-11-01

62

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

63

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

64

Maximum Power Point  

NSDL National Science Digital Library

Students learn how to find the maximum power point (MPP) of a photovoltaic (PV) panel in order to optimize its efficiency at creating solar power. They also learn about real-world applications and technologies that use this technique, as well as Ohm's law and the power equation, which govern a PV panel's ability to produce power.

Integrated Teaching And Learning Program

65

Maximum Tolerated Dose Studies  

Microsoft Academic Search

A three-stage maximum repeatable dose (MRD) protocol is described in which the MRD is established by dose incrementation, followed by administration of this dose for at least seven days, with the final stage being single dose administration of the doses anticipated for the one-month studies. The toxicokinetic measurements which are made in support of this protocol are illustrated with data

P. F. Carey; N. W. Spurling

1994-01-01

66

6 reach SUMMer 2013 and the Agile  

E-print Network

6 reach SUMMer 2013 CreA and the Agile #12;SUMMer 2013 reach 7 Or we'd just like to be better has led her to develop a unique frame- work to describe what she refers to as agility of mind or agile thinking. In simplest terms, Koutstaal defines the agile mind as one that moves nimbly back and forth

Koutstaal, Wilma

67

A model for learning human reaching movements  

Microsoft Academic Search

Reaching movement is a fast movement to- wards a given target. The main characteristics of such a movement are straight path and a bell-shaped speed profile. In this work a mathematical model for the con- trol of the human arm during ballistic reaching move- ments is presented. The model of the arm contains a 2 de- grees of freedom planar

Amir Karniel; Gideon F. Inbar

1997-01-01

68

Biology, not environment, drives major patterns in maximum tetrapod body size through time.  

PubMed

Abiotic and biological factors have been hypothesized as controlling maximum body size of tetrapods and other animals through geological time. We analyse the effects of three abiotic factors--oxygen, temperature and land area--on maximum size of Permian-Jurassic archosauromorphs and therapsids, and Cenozoic mammals, using time series generalized least-squares regression models. We also examine maximum size growth curves for the Permian-Jurassic data by comparing fits of Gompertz and logistic models. When serial correlation is removed, we find no robust correlations, indicating that these environmental factors did not consistently control tetrapod maximum size. Gompertz models--i.e. exponentially decreasing rate of size increase at larger sizes--fit maximum size curves far better than logistic models. This suggests that biological limits such as reduced fecundity and niche space availability become increasingly limiting as larger sizes are reached. Environmental factors analysed may still have imposed an upper limit on tetrapod body size, but any environmentally imposed limit did not vary substantially during the intervals examined despite variation in these environmental factors. PMID:22513278

Sookias, Roland B; Benson, Roger B J; Butler, Richard J

2012-08-23

69

Hypoxia and platelet-derived growth factor-BB synergistically upregulate the expression of vascular endothelial growth factor in vascular smooth muscle cells  

Microsoft Academic Search

Vascular endothelial growth factor (VEGF) mRNA expression was analysed in rabbit vascular smooth muscle cells following exposure to hypoxia and platelet-derived growth factor-BB (PDGF-BB). Hypoxia potently upregulated VEGF mRNA steady-state levels in a time- and concentration-dependent manner reaching a maximum level (?30-fold increase) after 12–24 h at 0% 02. In contrast, PDGF-BB caused a modest increase in VEGF expression. However,

George T. Stavri; Ying Hong; Ian C. Zachary; Georg Breier; Paul A. Baskerville; Seppo Ylä-Herttuala; Werner Risau; John F. Martin; Jorge D. Erusalimsky

1995-01-01

70

Ebola Donations Slow to Reach West Africa  

MedlinePLUS

... sharing features on this page, please enable JavaScript. Ebola Donations Slow to Reach West Africa Just 40 ... Preidt Wednesday, February 4, 2015 Related MedlinePlus Pages Ebola International Health WEDNEDAY, Feb. 4, 2015 (HealthDay News) -- ...

71

Well control procedures for extended reach wells  

E-print Network

Introduction to Extended Reach Drilling (ERD)............................................................ 1 BP's Wytch Farm oilfield ............................................................................................... 2 Well...-control challenges in ERD wells ........................................................................... 3 Simulating wellbore pressures during a kill procedure .................................................. 5 WELL CONTROL METHODS...

Gjorv, Bjorn

2004-09-30

72

Maximum gravitational recoil.  

PubMed

Recent calculations of gravitational radiation recoil generated during black-hole binary mergers have reopened the possibility that a merged binary can be ejected even from the nucleus of a massive host galaxy. Here we report the first systematic study of gravitational recoil of equal-mass binaries with equal, but counteraligned, spins parallel to the orbital plane. Such an orientation of the spins is expected to maximize the recoil. We find that recoil velocity (which is perpendicular to the orbital plane) varies sinusoidally with the angle that the initial spin directions make with the initial linear momenta of each hole and scales up to a maximum of approximately 4000 km s-1 for maximally rotating holes. Our results show that the amplitude of the recoil velocity can depend sensitively on spin orientations of the black holes prior to merger. PMID:17677894

Campanelli, Manuela; Lousto, Carlos O; Zlochower, Yosef; Merritt, David

2007-06-01

73

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

74

Cerebral cortical mechanisms of reaching movements.  

PubMed

Because reaching movements have a clear objective--to bring the hand to the spatial location of an object--they are well suited to study how the central nervous system plans a purposeful act from sensory input to motor output. Most models of movement planning propose a serial hierarchy of analytic steps. However, the central nervous system is organized into densely interconnected populations of neurons. This paradox between the apparent serial order of central nervous system function and its complex internal organization is strikingly demonstrated by recent behavioral, modeling, and neurophysiological studies of reaching movements. PMID:1549781

Kalaska, J F; Crammond, D J

1992-03-20

75

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 earth’s 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

76

The sun and heliosphere at solar maximum.  

PubMed

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's 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. PMID:14615526

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

2003-11-14

77

What Determines Limb Selection for Reaching?  

ERIC Educational Resources Information Center

While motor dominance appears to drive limb selection for reaching movements at the midline and ipsilateral (dominant) side, this study examined the possible determinants associated with what drives the programming of movements in response to stimuli presented in contralateral space. Experiment 1 distinguished between object proximity and a…

Helbig, Casi Rabb; Gabbard, Carl

2004-01-01

78

Hard-to-reach populations in Japan.  

PubMed

The objective of this study was to assess the trends of sampling locations and methods of studying hard-to-reach populations conducted in Japan. We accessed a Japanese medical database on 30 September 2005 to review 5 study types of hard-to-reach populations conducted in Japan: men who have sex with men, homeless, sex workers, undocumented migrants, and injecting drug users. We then categorized their sampling locations and methods. We found 298 articles on hard-to-reach populations published from 1983 to September 2005. Of the 285 studies sampled, approximately 92% were facility-based studies and the rest were community-based. This tendency was consistent in each subgroup; the majority of the studies were conducted among patients in medical facilities. Our study shows the majority of studies on hard-to-reach populations in Japan adopted a convenience sampling method and were facility-based. We suggest the utilization of comparatively valid techniques, such as time-location or respondent driven sampling to more clearly understand these populations. PMID:17539282

Nomura, Yuka; Poudel, Krishna C; Jimba, Masamine

2007-03-01

79

Can cosmic strangelets reach the earth?  

PubMed

The mechanism for the propagation of strangelets with low baryon number through the atmosphere of the Earth has been explored. It has been shown that, under suitable initial conditions, such strangelets may indeed reach depths near mountain altitudes with mass numbers and charges close to the observed values in cosmic ray experiments. PMID:10970510

Banerjee; Ghosh; Raha; Syam

2000-08-14

80

Reaching Rural Women: Case Studies and Strategies.  

ERIC Educational Resources Information Center

Although not often considered in the past by planners because their economic contributions are not performed for money, rural women are contributors to the development of their countries. The urgency of reaching women with important information to break the cycle of poverty is now being recognized by the major development agencies. While there are…

Colle, Royal D.; Fernandez de Colle, Susana

81

Directional technology will extend drilling reach  

Microsoft Academic Search

Extended reach drilling (ERD) is an advanced methodology for drilling high-angle well bores with significantly increased horizontal displacements. Such well bores offer a variety of applications with the potential for reducing production costs. Problems of pipe movement, differential sticking, hole cleaning, and applying weight on bit can be reduced by the use of available technology. A field test drilling program

T. B. Dellinger; W. Gravley; G. C. Tolle

1980-01-01

82

Approximating Human Reaching Volumes Using Inverse Kinematics  

E-print Network

, Switzerland Abstract This paper presents a system to analyse the reaching capabilities of the human body. Our system for the human body. Our research is motivated due to the necessity of systems which help to manage. Introduction Virtual Humans are a valuable medium for gaining knowledge and understanding about the human body

Rodríguez, Inmaculada

83

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

84

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

85

OSMOTIC STRESS-INDUCED CHANGES IN GERMINATION, GROWTH AND SOLUBLE SUGAR CONTENT OF SORGHUM BICOLOR (L.) MOENCH SEEDS  

Microsoft Academic Search

Summary. The effect of osmotic stress on germination, growth and soluble sugar content in Sorghum bicolor (L.) Moench cv. CSH 9 seeds and seedling components (endosperm and embryos) during early germination was inves- tigated. Under stress conditions germination decreased markedly, whereas the control at the same time reached its maximum germination (99%). A high percentage (67%) of ungerminated seeds from

Prabhjot Kaur Gill; Arun Dev Sharma; Prabhjeet Singh; Sukdev Singh Bhullar

2002-01-01

86

Rain and hail can reach the surface of Titan  

NASA Astrophysics Data System (ADS)

We have calculated the condensation and evaporation of ternary CH 4-N 2-C 2H 6 liquid drops and solid CH 4 hail as they fall through Titan's lower atmosphere to determine the likelihood that precipitation reaches the ground. Assuming the humidity profile determined by the Huygens probe, binary liquid CH 4/N 2 condensate grows in the region from ˜8 to 15 km in Titan's atmosphere because the combined humidity of CH 4 and N 2 exceeds saturation. These drops evaporate below ˜8 km. We determine the fate of 10 ?m seeds composed of ethane, which is expected to provide condensation sites. In addition, we study the fate of already formed raindrops with radii of 1-4.75 mm falling out of the growth region. High (50%) and low (0%) ethane relative humidities (RH) are considered in the calculation. We find that drops with radii ˜3 mm and smaller dropping from 8 km reach the ground in compositional equilibrium with the atmosphere in the high ethane RH case as a result of the stabilizing influence of the ethane, and evaporate in the atmosphere in the low ethane RH case. Large drops (>˜3 mm) reach the surface large and cold because the latent heat loss due to the evaporation of methane cools the drop and slows the evaporation rate. Pure methane hail hits the ground if its radius is initially more than 4 mm at 16 km above the surface and sublimates in the atmosphere if its radius is smaller.

Graves, S. D. B.; McKay, C. P.; Griffith, C. A.; Ferri, F.; Fulchignoni, M.

2008-03-01

87

Dynamic maximum power point tracker for photovoltaic applications  

Microsoft Academic Search

A dynamic process for reaching the maximum power point of a variable power source such as a solar cell is introduced. The process tracks maximum power nearly cycle-by-cycle during transients. Information from the natural switching ripple instead of external perturbation is used to support the maximizing process. The method is globally stable for DC-DC power converters, provided that a switching

Pallab Midya; Philip T. Krein; Robert J. Turnbull; Robert Reppa; Jonathan Kimball

1996-01-01

88

Last Glacial Maximum  

NSDL National Science Digital Library

Short lecture on CLIMAP project (see PowerPoint) 20 minutes Powerpoint (PowerPoint 444kB Nov7 10) Group activity - Reading for CLIMAP study assumptions, 20 minutes to read, 20 minutes for discussion Student Handout (Microsoft Word 50kB Nov7 10) Students break into groups (4 per group is good division of work) with 2 students per paper. Split the assumptions between students. Each group skims the CLIMAP papers for the assumptions (modern and/or LGM) used in the CLIMAP model-based reconstruction of the LGM. In the groups, students compare the assumptions between papers. Resources: CLIMAP (1976), The surface of the ice-age earth, Science, 191(4232), 1131-1137 and CLIMAP (1984), The last interglacial ocean, Quaternary Research, 21(2), 123. Class Discussion - Summarize assumptions used in CLIMAP studies. Group activity Exploring CLIMAP LGM Reconstructions, 40 minutes for model data, 20 minutes for discussion (Could be modified with as a "jigsaw" activity with a larger class). Learn more about the jigsaw teaching method. Students work on this activity in pairs; one person will create LGM maps, the other modern. Students should sit together with their computer monitors close together to compare. The students will use the IRI/LDEO Climate Data Library to access the CLIMAP reconstruction and produce maps using the tools available on this web site. In a web browser, go to http://iridl.ldeo.columbia.edu/SOURCES/.CLIMAP/ This is the main page for the CLIMAP Model output for the LGM 18,000 BP. In the middle of the page is the label "Datasets and variables" with two data sets below http://iridl.ldeo.columbia.edu/SOURCES/.CLIMAP/.LGM/ and http://iridl.ldeo.columbia.edu/SOURCES/.CLIMAP/.MOD/. Each student clicks on the link they are assigned to. There are several data sets listed for each period and the students will examine each data set and compare the LGM and Modern. As a class, go through each data set allowing pairs to compare the maps then summarize the results as a class. The worksheet has a table for the students and the PowerPoint has table for summarizing. Class Discussion - Summarize differences between modern and LGM in the CLIMAP model output. Discuss how the assumptions of the CLIMAP model studies may have influenced the results. Extra activities The students can explore the data further using the data selection and filters in the IRI/LDEO Climate Data Library. For the two SST data sets, click on "Data Selection" and narrow the data to the just the tropics (23.5º N-S). Click on "Filters" then select XY next to "Average over." The next window gives you the average over the tropics close to the top of the page. In the next class, the students repeat the Readings exercise by reading the COHMAP and MARGO papers to see how the scientific knowledge has progressed since the original CLIMAP studies. COHMAP Members, (1988), Climatic Changes of the Last 18,000 Years: Observations and Model Simulations, Science, 241(4869), 1043-1052. MARGO (2009), Constraints on the magnitude and patterns of ocean cooling at the Last Glacial Maximum, Nature Geoscience, 2(2), 127-132.

Kristine DeLong

89

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

90

AGU Scholarship Fund Reaches Its Goal  

NASA Astrophysics Data System (ADS)

The Edmond M. Dewan Young Scientist Scholarship fund has reached its goal of $25,000. Those who donated to the fund share AGU's mission in taking an active role in educating and nurturing the next generation of scientists and ensuring a sustainable future for society. Thanks to the generosity of more than 100 members of the AGU and science community, a deserving graduate student of atmospheric or space physics will receive financial assistance to further his or her research and advance his or her research and future career.

Howard, Claire

2014-11-01

91

Spallation Neutron Source reaches megawatt power  

ScienceCinema

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

2010-01-08

92

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

93

Reaching Diverse Audiences through NOAO Education Programs  

NASA Astrophysics Data System (ADS)

NOAO education programs are designed to reach diverse audiences. Examples described in this poster include the Hands-On Optics Project nationwide, an extension of the Hands-On Optics program at Boys and Girls Clubs in Arizona and in Hawaii, a professional development program for Navajo and Hopi teachers, a number of programs for the Tohono O'odham Nation, and a project collecting and reviewing Spanish language astronomy materials. Additionally NOAO is also involved in several local outreach projects for diverse and underserved audiences.

Pompea, Stephen M.; Sparks, R. T.; Walker, C. E.

2009-01-01

94

Reach Out, Reach Out and Beep Someone: People Communicate Better via Computer.  

ERIC Educational Resources Information Center

An electronic mail system used by and within a college development office provides a communication network reaching all parts of the institution's administration and colleagues nationwide. The applications include sending individual or group messages, teleconferencing, and maintenance of files. (MSE)

Gilbert, Arlene M.

1983-01-01

95

Growth kinetics of the Golgi apparatus during the cell cycle in onion root meristems.  

PubMed

In onion root meristems, the number of dictyosomes per cell shows a kinetics of growth strongly related to the cell cycle. During the interphase of steady-state proliferative cells, the volume density and numerical density of the Golgi apparatus decrease to reach minimum values in late-interphase cells, characterized by their greatest length. This pattern is also found in the total volume occupied by Golgi apparatus. Once in mitosis, the above-mentioned parameters begin to increase reaching maximum mean values in telophase. After the experimental uncoupling of chromosome and growth cycles by presynchronization with hydroxyurea, we found a similar behaviour pattern in the Golgi apparatus: decreasing values during interphase and a triggering of Golgi-apparatus growth in prophase independently of the bigger cell sizes reached in mitosis as an effect of pretreatment with hydroxyurea. These results indicate a cyclic kinetics of this subcellular component in higher-plant meristems, coupled with early mitotic events. PMID:24221867

Garcia-Herdugo, G; González-Reyes, J A; Gracia-Navarro, F; Navas, P

1988-09-01

96

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

97

Reach and get capability in a computing environment  

DOEpatents

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

98

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

99

Submovements during reaching movements after stroke.  

PubMed

Neurological deficits after cerebrovascular accidents very frequently disrupt the kinematics of voluntary movements with the consequent impact in daily life activities. Robotic methodologies enable the quantitative characterization of specific control deficits needed to understand the basis of functional impairments and to design effective rehabilitation therapies. In a group of right handed chronic stroke survivors (SS) with right side hemiparesis, intact proprioception, and differing levels of motor impairment, we used a robotic manipulandum to study right arm function during discrete point-to-point reaching movements and reciprocal out-and-back movements to visual targets. We compared these movements with those of neurologically intact individuals (NI). We analyzed the presence of secondary submovements in the initial (i.e. outward) trajectory portion of the two tasks and found that the SS with severe impairment (FM <; 30) presented arm submovements that differed notably not only from NI but also from those of SS with moderate arm impairment (FM 30-50). Therefore the results of this pilot study suggest that in SS arm kinematics vary significantly across differing levels of motor impairment. Our results support the development of rehabilitation therapies carefully tailored to each individual stroke survivor. PMID:25571204

Simo, Lucia S; Piovesan, Davide; Laczko, Jozsef; Ghez, Claude; Scheidt, Robert S

2014-08-01

100

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

101

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

102

Prism Adaptation of Reaching Movements: Specificity for the Velocity of Reaching  

Microsoft Academic Search

Accurate reaching toward a visual target is disturbed after the visual field is displaced by prisms but recovers with practice. When the prisms are removed, subjects misreach in the direc- tion opposite to the prism displacement (aftereffect). The present study demonstrated that the severity of the aftereffect depends on the velocity of the movements during and after the visual displacement.

Shigeru Kitazawa; Tatsuya Kimura; Takanori Uk

103

Comparison of Robot-Assisted Reaching to Free Reaching in Promoting Recovery  

E-print Network

. To date, ten subjects have completed twenty-four therapy sessions over an eight-week period, randomized to either a robot exercise group (N = 6) or non-robotic exercise group (N = 4). For the robot exercise group, the subjects performed unassisted, unrestrained reaching exercises to the same targets for the same number

Reinkensmeyer, David J.

104

San Acacia Reach San Acacia Dam to Escondida Bridge  

E-print Network

San Acacia Reach San Acacia Dam to Escondida Bridge Hydraulic Modeling Analysis 1918-2006 Middle, hydraulic modeling analyses have been performed on the San Acacia reach to determine the changes by Reclamation on the San Acacia reach. The 11.6 mile long reach extends from the San Acacia Diversion dam (River

Julien, Pierre Y.

105

Columbia River Estuary Ecosystem Classification Hydrogeomorphic Reach  

USGS Publications Warehouse

Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

2012-01-01

106

Predicting species' maximum dispersal distances from simple plant traits.  

PubMed

Many studies have shown plant species' dispersal distances to be strongly related to life-history traits, but how well different traits can predict dispersal distances is not yet known. We used cross-validation techniques and a global data set (576 plant species) to measure the predictive power of simple plant traits to estimate species' maximum dispersal distances. Including dispersal syndrome (wind, animal, ant, ballistic, and no special syndrome), growth form (tree, shrub, herb), seed mass, seed release height, and terminal velocity in different combinations as explanatory variables we constructed models to explain variation in measured maximum dispersal distances and evaluated their power to predict maximum dispersal distances. Predictions are more accurate, but also limited to a particular set of species, if data on more specific traits, such as terminal velocity, are available. The best model (R2 = 0.60) included dispersal syndrome, growth form, and terminal velocity as fixed effects. Reasonable predictions of maximum dispersal distance (R2 = 0.53) are also possible when using only the simplest and most commonly measured traits; dispersal syndrome and growth form together with species taxonomy data. We provide a function (dispeRsal) to be run in the software package R. This enables researchers to estimate maximum dispersal distances with confidence intervals for plant species using measured traits as predictors. Easily obtainable trait data, such as dispersal syndrome (inferred from seed morphology) and growth form, enable predictions to be made for a large number of species. PMID:24669743

Tamme, Riin; Götzenberger, Lars; Zobel, Martin; Bullock, James M; Hooftman, Danny A P; Kaasik, Ants; Pärtel, Meelis

2014-02-01

107

When could global warming reach 4°C?  

PubMed

The Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) assessed a range of scenarios of future greenhouse-gas emissions without policies to specifically reduce emissions, and concluded that these would lead to an increase in global mean temperatures of between 1.6°C and 6.9°C by the end of the twenty-first century, relative to pre-industrial. While much political attention is focused on the potential for global warming of 2°C relative to pre-industrial, the AR4 projections clearly suggest that much greater levels of warming are possible by the end of the twenty-first century in the absence of mitigation. The centre of the range of AR4-projected global warming was approximately 4°C. The higher end of the projected warming was associated with the higher emissions scenarios and models, which included stronger carbon-cycle feedbacks. The highest emissions scenario considered in the AR4 (scenario A1FI) was not examined with complex general circulation models (GCMs) in the AR4, and similarly the uncertainties in climate-carbon-cycle feedbacks were not included in the main set of GCMs. Consequently, the projections of warming for A1FI and/or with different strengths of carbon-cycle feedbacks are often not included in a wider discussion of the AR4 conclusions. While it is still too early to say whether any particular scenario is being tracked by current emissions, A1FI is considered to be as plausible as other non-mitigation scenarios and cannot be ruled out. (A1FI is a part of the A1 family of scenarios, with 'FI' standing for 'fossil intensive'. This is sometimes erroneously written as A1F1, with number 1 instead of letter I.) This paper presents simulations of climate change with an ensemble of GCMs driven by the A1FI scenario, and also assesses the implications of carbon-cycle feedbacks for the climate-change projections. Using these GCM projections along with simple climate-model projections, including uncertainties in carbon-cycle feedbacks, and also comparing against other model projections from the IPCC, our best estimate is that the A1FI emissions scenario would lead to a warming of 4°C relative to pre-industrial during the 2070s. If carbon-cycle feedbacks are stronger, which appears less likely but still credible, then 4°C warming could be reached by the early 2060s in projections that are consistent with the IPCC's 'likely range'. PMID:21115513

Betts, Richard A; Collins, Matthew; Hemming, Deborah L; Jones, Chris D; Lowe, Jason A; Sanderson, Michael G

2011-01-13

108

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

109

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

110

Common Sense and Maximum Entropy  

Microsoft Academic Search

This paper concerns the question of how to draw inferences common sensically from uncertain knowledge. Since the early work of Shore and Johnson, [10], Paris and Vencovsk a, [6], and Csiszár, [1], it has been known that the Maximum Entropy Inference Process is the only inference process which obeys certain common sense principles of uncertain reasoning. In this paper we

Jeff Paris

2000-01-01

111

Maximum throughput of clandestine relay  

Microsoft Academic Search

The maximum throughput of relaying information flows while concealing their presence is studied. The concealment is achieved by embedding transmissions of information flows into truly independent transmission schedules that resemble the normal transmission behaviors without any flow. Such embedding may reduce the throughput for delay-sensitive flows, and the paper provides a quantitative characterization of the level of reduction. Under a

Ting He; Lang Tong; Ananthram Swami

2009-01-01

112

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

113

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

114

Segmental Trunk Control Acquisition and Reaching in Typically Developing Infants  

PubMed Central

This study explored the influence of an external support at the thoracic and pelvic level of the trunk on the success of reaching, postural stability and reaching kinematics while infants reached for a toy. Seventeen infants (4–6 months) were clustered into two groups according to their trunk control assessed with the Segmental Assessment of Trunk Control (SATCo). Major differences were seen between groups with pelvic support, whereas with thoracic support, all infants showed similar quality reaching behaviours. With the external pelvic support, infants who had acquired trunk control in the lumbar region were more accurate in their reaching movements (less movement time, improved straightness of reach, less movement units and path length per movement unit) and were more stable (decreased trunk and head displacement) during a reach than infants that had only acquired trunk control in the thoracic region. These results support the hypothesis that trunk control influences the quality of reaching behaviour. PMID:23681292

Rachwani, Jaya; Santamaria, Victor; Saavedra, Sandra L.; Wood, Stacy; Porter, Francine; Woollacott, Marjorie H.

2013-01-01

115

Modulation of hand aperture during reaching in persons with incomplete cervical spinal cord injury.  

PubMed

The intact neuromotor system prepares for object grasp by first opening the hand to an aperture that is scaled according to object size and then closing the hand around the object. After cervical spinal cord injury (SCI), hand function is significantly impaired, but the degree to which object-specific hand aperture scaling is affected remains unknown. Here, we hypothesized that persons with incomplete cervical SCI have a reduced maximum hand opening capacity but exhibit novel neuromuscular coordination strategies that permit object-specific hand aperture scaling during reaching. To test this hypothesis, we measured hand kinematics and surface electromyography from seven muscles of the hand and wrist during attempts at maximum hand opening as well as reaching for four balls of different diameters. Our results showed that persons with SCI exhibited significantly reduced maximum hand aperture compared to able-bodied (AB) controls. However, persons with SCI preserved the ability to scale peak hand aperture with ball size during reaching. Persons with SCI also used distinct muscle coordination patterns that included increased co-activity of flexors and extensors at the wrist and hand compared to AB controls. These results suggest that motor planning for aperture modulation is preserved even though execution is limited by constraints on hand opening capacity and altered muscle co-activity. Thus, persons with incomplete cervical SCI may benefit from rehabilitation aimed at increasing hand opening capacity and reducing flexor-extensor co-activity at the wrist and hand. PMID:25511164

Stahl, Victoria A; Hayes, Heather B; Buetefisch, Cathrin M; Wolf, Steven L; Trumbower, Randy D

2015-03-01

116

What causes cooling water temperature gradients in a forested stream reach?  

NASA Astrophysics Data System (ADS)

Previous studies have suggested that shading by riparian vegetation may reduce maximum water temperatures 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 without 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 land use transitions from open moorland to semi-natural, predominantly deciduous woodland. Observations were made along a 1050 m reach using a spatially distributed network of 10 water temperature data loggers, 3 automatic weather stations and 211 hemispherical photographs that 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. Net energy gains occurred along the reach, predominantly 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 increased in the streamwise direction; a maximum instantaneous 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 by >1 h. 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 overcast 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.

2014-12-01

117

Far-Reaching Impacts of African Dust- A Calipso Perspective  

NASA Technical Reports Server (NTRS)

African dust can transport across the tropical Atlantic and reach the Amazon basin, exerting far-reaching impacts on climate in downwind regions. The transported dust influences the surface-atmosphere interactions and cloud and precipitation processes through perturbing the surface radiative budget and atmospheric radiative heating and acting as cloud condensation nuclei and ice nuclei. Dust also influences biogeochemical cycle and climate through providing nutrients vital to the productivity of ocean biomass and Amazon forests. Assessing these climate impacts relies on an accurate quantification of dust transport and deposition. Currently model simulations show extremely large diversity, which calls for a need of observational constraints. Kaufman et al. (2005) estimated from MODIS aerosol measurements that about 144 Tg of dust is deposited into the tropical Atlantic and 50 Tg of dust into the Amazon in 2001. This estimated dust import to Amazon is a factor of 3-4 higher than other observations and models. However, several studies have argued that the oversimplified characterization of dust vertical profile in the study would have introduced large uncertainty and very likely a high bias. In this study we quantify the trans-Atlantic dust transport and deposition by using 7 years (2007-2013) observations from CALIPSO lidar. CALIPSO acquires high-resolution aerosol extinction and depolarization profiles in both cloud-free and above-cloud conditions. The unique CALIPSO capability of profiling aerosols above clouds offers an unprecedented opportunity of examining uncertainties associated with the use of MODIS clear-sky data. Dust is separated from other types of aerosols using the depolarization measurements. We estimated that on the basis of 7-year average, 118142 Tg of dust is deposited into the tropical Atlantic and 3860 Tg of dust into the Amazon basin. Substantial interannual variations are observed during the period, with the maximum to minimum ratio of about 1.6 and 2.5 for the deposition to the tropical Atlantic and Amazon, respectively. The MODIS-based estimates appear to fall within the range of CALIPSO-based estimates; and the difference between MODIS and CALIPSO estimates can be largely attributed to the interannual variability, which is corroborated by long-term surface dust concentration observations in the tropical Atlantic. Considering that CALIPSO generally tends to underestimate the aerosol loading, our estimate is likely to represent a low bound for the dust transport and deposition estimate. The finding suggests that models have substantial biases and considerable effort is needed to improve model simulations of dust cycle.

Yu, Hongbin; Chin, Mian; Yuan, Tianle; Bian, Huisheng; Prospero, Joseph; Omar, Ali; Remer, Lorraine; Winker, David; Yang, Yuekui; Zhang, Yan; Zhang, Zhibo

2014-01-01

118

Modifications to the Standard Sit-and-Reach Flexibility Protocol  

PubMed Central

Objective: To present several modifications of the standard sit-and-reach protocol. Background: Many exercises designed to increase strength and aerobic capacity tend to decrease the flexibility of the erector spinae and hamstrings musculature. Less-than-ideal flexibility in these soft tissues may increase the risk of injury during training, competition, or activities of daily living. The most widely used measures of flexibility have been either the stand-and-reach or the sit-and-reach, but both are limited to a single measure. Description: Using the new multitest flexometer, we were able to take 6 flexibility measures beyond the stand-and-reach test: standard active sit-and-reach, standard passive sit-and-reach, modified active sit-and-reach with external rotators slackened, modified passive sit-and-reach with external rotators slackened, modified active sit-and-reach with the hamstrings, gastrocnemii, and external rotators slackened, and modified passive sit-and-reach with the hamstrings, gastrocnemii, and external rotators slackened. Clinical Advantages: This modified sit-and-reach protocol allows the indirect assessment of the influence of the 4 major muscle groups that affect sit-and-reach scores: erector spinae, hip rotators, hamstrings, and gastrocnemii. ImagesFigure 1.Figure 2.Figure 3. PMID:16558547

Holt, Laurence E.; Pelham, Thomas W.; Burke, Darren G.

1999-01-01

119

DRAFT San Acacia Reach San Acacia Dam to Escondida Bridge  

E-print Network

DRAFT San Acacia Reach San Acacia Dam to Escondida Bridge Hydraulic Modeling Analysis 1918, hydraulic modeling analyses have been performed on the San Acacia reach to determine the changes by Reclamation on the San Acacia reach. The 11.6 mile long extends from the San Acacia Diversion dam (River Mile

Julien, Pierre Y.

120

Behavioral inflexibility and motor dedifferentiation in persons with Parkinson's disease: Bilateral coordination deficits during a unimanual reaching task.  

PubMed

We evaluated kinematics of people with Parkinson's disease (PD) and age-matched controls during cued and uncued reaching movements. Maximum hand velocity, its variability and shoulder-to-shoulder coupling, quantified by phase locking value (PLV), were compared between PD (n=14) and Control (n=4). The PD group achieved significantly lower maximum hand velocities during the reaching movement in comparison to the Control group (p=0.05), whereas the Control group exhibited significantly greater variability (i.e., larger SDs) of maximum hand velocities across the blocks than the PD group (p=0.01). Persons with PD exhibited higher PLVs than the healthy elderly individuals when performing reaching movements with their dominant side (p=0.05), while the PLVs did not differ between groups when the movements were performed with their non-dominant hand. The present study suggests that persons with PD have a reduced ability to: (1) modulate maximum reaching velocity; and (2) alter coordination across the shoulders to different reaching actions. In persons with PD, the velocity-oriented (dominant) limb becomes slowed and less flexible, to the point that its movement dynamics are effectively similar to that of the position-oriented (non-dominant) limb. PMID:25451729

Amano, Shinichi; Hong, S Lee; Sage, Jacob I; Torres, Elizabeth B

2015-01-12

121

Total Maximum Daily Load Program  

NSDL National Science Digital Library

The Environmental Protection Agency (EPA) provides this informative resource on Total Maximum Daily Loads (TMDL). A term used to discuss water quality, TMDL refers to "a calculation of the maximum amount of a pollutant that a water body can receive and still meet water quality standards." The TMDL Program Website offers background information on TMDLs (including FAQs), a National Overview of Impaired Waters in the US, and two standard presentations on TMDLs (HTML and Power Point). The heart of the site, however, is the interactive map of the US, which allows users access to each state's TMDL Program. Within each state, watershed names and maps, as well as source information (Water body, Parameter of Concern, Priority for TMDL Development), are provided.

122

[A growth study of Prioria copaifera (Caesalpinaceae) using dendrochronological techniques].  

PubMed

The Cativo (Prioria copaifera) forms very homogeneous forests called cativales in the flooded plains of some rivers from Costa Rica to Colombia. For over 70 years Cativo has been the main base of the timber industry in the Colombian Darien area. Because of high productivity and high-dominance of Cativo trees, they represent one of the most prone tropical forests for sustainable forest management. The objective of this research is to model diameter and timber volume growth and growth rates (absolute, mean and relative) of Cativo as a function of age, using tree ring data derived from dendrochronologycal techniques. We evaluated the annual nature of the tree rings by radiocarbon analysis and crossdating techniques. Besides, the diameter and volume growth was modeled using von Bertalanffy's model. As of our results, we estimated the life span of Cativo in 614 years as the time required to reach 99% of the asymptotic diameter. By the mean value we have found that the mean rate of diameter growth is 0.31cm/y. The species requires 90 years to reach 40cm in diameter, the regulated cut diameter in Colombia. We find that Cativo reaches maximum current annual increment (ICA) in diameter at 40 years and in volume at 90 years with rates of 0.5cm/y and 0.032m3/y per tree, respectively. The maximum diameter mean annual increments (MAI) are achieved at 80 years and for the volume at 140 year, with growth rates of 0.45cm/y and 0.018m3/y per tree, respectively. The generated information is useful for the sustainable management of Cativò forests. PMID:22208095

Giraldo Jiménez, Jorge Andrés; del Valle Arango, Jorge Ignacio

2011-12-01

123

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

124

Clades reach highest morphological disparity early in their evolution  

PubMed Central

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

2013-01-01

125

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, B. J.; Coe, H. H.; Coy, J. J.

1991-01-01

126

[Effects of nitrogen form on growth and quality of Chrysanthemums morifolium].  

PubMed

This paper is aimed to study the effects of nitrogen form on the growth and quality of Chrysanthemums morifolium at the same nitrogen level. In order to provide references for nutrition regulation of Ch. morifolium in field production, pot experiments were carried out in the greenhouse at experimental station of Nanjing Agricultural University. Five proportions of ammonium and nitrate nitrogen were set up and a randomized block design was applied four times repeatedly. The results showed that the growth and quality of Ch. morifolium were significantly influenced by the nitrogen form. The content of chlorophyll and photosynthesis rate were the highest at the NH4(+) -N /NO3(-) -N ratio of 25:75; The activities of NR in different parts of Ch. -morifolium reached the highest at the NH4(+) - N/NO3(-) -N ratio of 0: 100. The contents of nitrate nitrogen in the root and leaves reached the highest at the NH4(+) -N/NO3(-) -N ratio of 50:50. The activities of GS, GOGAT and the content of amylum increased with the ratio of NO3(-) -N decreasing and reached it's maximum at the NH4 + -N/NO3 - -N ratio of 100: 0. The content of ammonium nitrogen were the highest at the NH4 + -N /NO3 --N ratio of 75: 25, while the content of soluble sugar reached the highest at the NH4(+)-N/NO3(-) -N ratio of 25: 75. The content of flavones, chlorogenic acid and 3,5-O-dicoffeoylqunic acid were 57.2 mg x g(-1), 0.673% and 1.838% respectively, reaching the maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75; The content of luteoloside increased with the ratio of NO3(-) -N increasing and reached it's maximum at the NH4(+) -N/NO3(-) -N ratio of 0: 100. The yield of Ch. morifolium reached it's maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75. Nitrogen form has some remarkable influence on the nitrogen metabolism, photosynthesis and growth, Nitrogen form conducive to the growth and quality of Ch. morifolium at the NH4(+) -N /NO3(-) -N ratio of 25: 75. PMID:25522608

Zhang, Peng; Wang, Kang-cai; Cheng, Ming-chao; Guo, Qing-hai; Zhao, Jie; Zhao, Xiu-Mei; Li, Li

2014-09-01

127

Localized maximum entropy shape modelling.  

PubMed

A core part of many medical image segmentation techniques is the point distribution model, i.e., the landmark-based statistical shape model which describes the type of shapes under consideration. To build a proper model, that is flexible and generalizes well, one typically needs a large amount of landmarked training data, which can be hard to obtain. This problem becomes worse with increasing shape complexity and dimensionality. This work presents a novel methodology applicable to principal component-based shape model building and similar techniques. The main idea of the method is to make regular PCA shape modelling more flexible by using merely covariances between neighboring landmarks. The remaining unknown second order moments are determined using the maximum entropy principle based on which the full covariance matrix--as employed in the PCA--is determined using matrix completion. The method presented can be applied in a variety of situations and in conjunction with other technique facilitating model building. The experiments on point distributions demonstrate that improved shape models can be obtained using this localized maximum entropy modelling. PMID:17633734

Loog, Marco

2007-01-01

128

Mark III Space Suit Mobility: A Reach Evaluation Case Study  

NASA Technical Reports Server (NTRS)

A preliminary assessment of the reach envelope and field of vision (FOV) for a subject wearing a Mark III space suit was requested for use in human-machine interface design of the Science Crew Operations and Utility Testbed (SCOUT) vehicle. The reach and view of two suited and unsuited subjects were evaluated while seated in the vehicle using 3-dimensional position data collected during a series of reaching motions. Data was interpolated and displayed in orthogonal views and cross-sections. Compared with unsuited conditions, medio-lateral reach was not strongly affected by the Mark III suit, whereas vertical and antero-posterior reach were inhibited by the suit. Lateral FOV was reduced by approximately 40 deg. in the suit. The techniques used in this case study may prove useful in human-machine interface design by providing a new means of developing and displaying reach envelopes.

Thaxton, Sherry S.; Abercromby, Andrew F. J.; Onady, Elizabeth A.; Rajulu, Sudhakar L.

2007-01-01

129

[Growth modeling of Albizia niopoides (Mimosaceae) using dendrochronological methods].  

PubMed

The annual growth rings in tropical trees are fairly common, but their study is relatively recent. Growth rings were found in trees of Albizia niopoides from the Porce River Canyon, Central Cordillera of the Colombian Andes. A total of 33 cross-sections were collected from trees distributed throughout the study area from 664-870masl. Cross-dating, spaguetti plot and 14C analyses were used to demonstrate ring annuality, assuming as hypothesis that these are real annual growth rings. A combination of descriptive analysis of time series (smoothing and pre-whitening) to filter climate noise and nonlinear regression with weighted residuals was used to fit the diameter to Korfs growth model, in which the coefficient of determination reaches values close to 100%. The positive residual autocorrelation of order 1, although not significant, is explained by the existence of energy reserves in the stem and by the accumulation of diameter increments required for the construction of the diameter growth model. The current and mean annual maximum increment rates are 1.03 and 0.94cm/year at ages 18 and 46 years old, respectively. These trees are classified within the group of fast growing species which can reach a cut diameter of over 50cm in approximately 52 years. PMID:23025084

Giraldo, Víctor David; del Valle, Jorge Ignacio

2012-09-01

130

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

131

Reaching Year 12 in Victoria, Australia: Student and School Influences  

ERIC Educational Resources Information Center

This paper examines student and school influences on reaching Year 12, the final year of schooling in Victoria, Australia. It analyses data from the population of students who were in Year 9 in 2008. Male, English-speaking background, government school, and especially Indigenous students were less likely to reach Year 12 than comparison groups.…

Marks, Gary

2014-01-01

132

Modifications to the Standard Sit-and-Reach Flexibility Protocol.  

ERIC Educational Resources Information Center

Describes several modifications of the standard sit-and-reach flexibility protocol using a new device called the multitest flexometer (MTF). Using the MTF, researchers could take six flexibility measures beyond the stand-and-reach test. The modified protocol allowed the indirect assessment of the influence of the four major muscle groups that…

Holt, Laurence E.; Burke, Darren G.; Pelham, Thomas W.

1999-01-01

133

Using Object Knowledge in Visual Tracking and Reaching  

E-print Network

Using Object Knowledge in Visual Tracking and Reaching Neil E. Berthier Department of Psychology for these infants, task demands interfered with the integration of visual information and visuospatial reasoning for object knowledge in contrast to the manual tasks that involve reaching and searching for objects used

Massachusetts at Amherst, University of

134

Reaching forward: effects of a preceding task and aging.  

PubMed

Forward reaching is an integral part of many essential daily activities. It is often performed while standing quietly or after standing up from a seated position. This study sought to determine how a preceding balance task and aging would affect the task performance and movement strategy. Twenty-two healthy young and 20 older adults participated in this study and performed forward reaching under two task conditions. In forward reach (FR), reaching was performed during quiet standing. In up-and-reach (UR), subjects stood up from a seated position and then reached forward. A motion analysis system was used to calculate the location of the center of mass (COM) and joint angles at the initial and final positions, and the finger, COM, and joint angular displacements during the reaching task. For both groups, UR was initiated in a more flexed posture and had a significantly shorter reach distance and greater ankle dorsiflexion angle, compared to FR. The location of the COM, however, did not differ between the two task conditions. Older adults were found to significantly slow down their downward and forward COM motions in UR but not young adults. These findings showed that a preceding balance task increased the task demand and required modifications in the movement strategy. For older adults, the impact of increased task demand was greater, and adopting a cautious strategy could help to complete the task safely. PMID:25637334

Tsai, Yi-Ju; Lin, Sang-I

2015-02-01

135

Corticospinal Control during Reach, Grasp, and Precision Lift in Man  

Microsoft Academic Search

Transcranial magnetic brain stimulation (TMS) was used to assess the influence of the corticospinal system on motor output in seven human subjects during a task in which they had to reach out, grasp, and lift an object. Stimuli, directed at the hand area of the motor cortex, were delivered at eight defined points during the task: during reach, at grip

R. N. Lemon; R. S. Johanss; G. Westling

1995-01-01

136

Are trout populations affected by reach-scale stream slope?  

Microsoft Academic Search

Reach-scale stream slope and the structure of associated physical habitats are thought to affect trout popula - tions, yet previous studies confound the effect of stream slope with other factors that influence trout populations. We isolated the effect of stream slope on trout populations by sampling reaches immediately upstream and downstream of 23 marked changes in stream slope on 18

Daniel J. Isaak; Wayne A. Hubert

2000-01-01

137

RESEARCH ARTICLE Unconstrained three-dimensional reaching in Rhesus monkeys  

E-print Network

seated, monkeys reached, grasped, and retrieved food items. We recorded three-dimensional kinematics Á Prehension Á Multi-joint Á Reach- to-grasp Á Kinematics Á Dynamics Á Muscle Á Electromyography Á) (Bernstein 1967). Specific coordination rules could facilitate the selection of movement patterns. Planar

Jindrich, Devin L.

138

Multiple Early Eocene Thermal Maximums  

NASA Astrophysics Data System (ADS)

Periodic dissolution horizons signifying abrupt shoaling of the lysocline and CCD are characteristic features of deep-sea sections and often attributed to Milankovitch forcing via their diagnostic frequencies. Prominent dissolution horizons also correspond to abrupt climate events, such as the Paleocene-Eocene thermal maximum (PETM), as a result of input of significant CH4 - CO2 into the ocean-atmosphere system. The question arises whether other significant dissolution horizons identified in sediments of late Paleocene and early Eocene age similar to the recently identified ELMO (Lourens et al., 2004) were formed as a result of greenhouse gas input, or whether they were related to cumulative effects of periodic changes in ocean chemistry and circulation. Here we report the discovery of a 3rd thermal maximum in early Eocene (about 52 Ma) sediments recovered from the South Atlantic during ODP Leg 208. The prominent clay layer was named the "X" event and was identified within planktonic foraminifer zone P7 and calcareous nannofossil zone CP10 at four Walvis Ridge Transect sites with a water depth range of 2000 m (Sites 1262 to 1267). Benthics assemblages are composed of small individuals, have low diversity and high dominance. Dominant taxa are Nuttallides truempyi and various abyssaminids, resembling the post PETM extinction assemblages. High-resolution bulk carbonate \\delta13C measurements of one of the more shallow Sites 1265 reveal a rapid about 0.6 per mill drop in \\delta13C and \\delta18O followed by an exponential recovery to pre-excursion \\delta13C values well known for the PETM and also observed for the ELMO. The planktonic foraminiferal \\delta13C records of Morozovella subbotina and Acaranina soldadoensis in the deepest Site 1262 show a 0.8 to 0.9 per mill drop, whereas the \\delta13C drop of benthic foraminifera Nuttallides truempyi is slightly larger (about 1 per mill). We are evaluating mechanisms for the widespread change in deep-water chemistry, its connection to the surface-water response, and the relationship of the event, as well as the PETM and ELMO, with current astronomical solutions (Laskar et al., 2004; Varadi et al., 2003). References 1. Lourens, L.J., Sluijs, A., Kroon, D., Zachos, J.C., Thomas, E., Roehl, U., and the ODP Leg 208 Shipboard Scientific Party, 2004. An early Eocene transient warming (~53 Ma): Implications for astronomically-paced early Eocene hyperthermal events.- Abstract, 8th International Conference on Paleoceanography (ICP), 5-10 September 2004, Biarritz, France. 2. F. Varadi, B. Bunnegar, M. Ghil, Astrophysical J. 592, 620-630 (2003). 3. J. Laskar et al., Astronomy and Astrophysics (2004).

Roehl, U.; Zachos, J. C.; Thomas, E.; Kelly, D. C.; Donner, B.; Westerhold, T.

2004-12-01

139

Time course of epiphyseal growth plate fusion in rat tibiae  

NASA Technical Reports Server (NTRS)

Although the rat is the most common animal model used in studying osteoporosis, it is often used inappropriately. Osteoporosis is a disease that most commonly occurs in humans long after growth plate fusion with the associated cessation of longitudinal bone growth, but there has been a question as to when or to what extent the rat growth plate fuses. To investigate this question, we used microcomputed X-ray tomography, at voxel resolutions ranging from (5.7 micro m)(3) to (11 micro m)(3), to image the proximal epiphyseal growth plates of both male (n = 19) and female (n = 15) rat tibiae, ranging in age from 2 to 25 months. The three-dimensional images were used to evaluate fusion of the epiphyseal growth plate by quantitating the amount of cancellous bone that has bridged across the growth plate. The results suggest that the time course of fusion of the epiphyseal growth plate follows a sigmoidal pattern, with 10% of the maximum number of bridges having formed by 3.9 months in the male tibiae and 5.8 months in the female tibiae, 50% of the maximum number of bridges having formed by 5.6 months in the male tibiae and 5.9 months in the female tibiae, and 90% of the total maximum of bridges have formed by 7.4 months for the males and 6.5 months for the females. The total volume of bridges per tibia at the age at which the maximum number of bridges per tibia has first formed is 0.99 mm(3)/tibia for the males and 0.40 mm(3)/tibia for the females. After the maximum number of bridges (-290 for females, -360 for males) have formed the total volume of bridges per tibia continues to increase for an additional 7.0 months in the males and 17.0 months for the females until they reach maximum values (-1.5 mm(3)/tibia for the males and -2.2 mm(3)/tibia for the females).

Martin, E. A.; Ritman, E. L.; Turner, R. T.

2003-01-01

140

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

141

The maximum height of grasses is determined by roots.  

PubMed

Grasses such as bamboos can produce upright stems more than 30 m tall, yet the processes that constrain plant height in this important group have never been investigated. Air embolisms form commonly in the water transport system of grasses and we hypothesised that root pressure-dependent refilling these embolisms should limit the maximum height of grass species to the magnitude of their root pressure. Confirming this hypothesis, we show that in 59 species of bamboo grown in two common gardens, the maximum heights of culms of 67 clones are closely predicted by the maximum measured root pressure overnight. Furthermore, we demonstrate that water transport in these bamboo species is dependent on root pressure to repair hydraulic dysfunction sustained during normal diurnal gas exchange. Our results established the critical importance of root pressure in the tallest grass species and provide a new basis for understanding the limits for plant growth. PMID:22489611

Cao, Kun-Fang; Yang, Shi-Jian; Zhang, Yong-Jiang; Brodribb, Tim J

2012-07-01

142

An inverse dynamic analysis on the influence of upper limb gravity compensation during reaching.  

PubMed

Muscular dystrophies (MDs) are characterized by progressive muscle wasting and weakness. Several studies have been conducted to investigate the influence of arm supports in an attempt to restore arm function. Lowering the load allows the user to employ the residual muscle force for movement as well as for posture stabilization. In this pilot study three conditions were investigated during a reaching task performed by three healthy subjects and three MD subjects: a control condition involving reaching; a similar movement with gravity compensation using braces to support the forearm; an identical reaching movement in simulated zero-gravity. In the control condition the highest values of shoulder moments were present, with a maximum of about 6 Nm for shoulder flexion and abduction. In the gravity compensation and zero gravity conditions the maximum shoulder moments were decreased by more than 70% and instead of increasing during reaching, they remained almost unvaried, fluctuating around an offset value less than 1 Nm. Similarly, the elbow moments in the control condition were the highest with a peak around 3.3 Nm for elbow flexion, while the moments were substantially reduced in the remaining two conditions, fluctuating around offset values between 0 to 0.5 Nm. In conclusion, gravity compensation by lower arm support is effective in healthy subjects and MD subjects and lowers the amount of shoulder and elbow moments by an amount comparable to a zero gravity environment. However the influence of gravity compensation still needs to be investigated on more people with MDs in order to quantify any beneficial effect on this population. PMID:24187187

Essers, J M N Hans; Meijer, Kenneth; Murgia, Alessio; Bergsma, Arjen; Verstegen, Paul

2013-06-01

143

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

144

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

145

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. PMID:24031622

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

2011-01-01

146

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. PMID:24868537

Merchán-Baeza, Jose Antonio; González-Sánchez, Manuel; Cuesta-Vargas, Antonio Ignacio

2014-01-01

147

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

148

HYDROMETEOROLOGICAL REPORT NO. 39 PROBABLE MAXIMUM PRECIPITATION"  

E-print Network

HYDROMETEOROLOGICAL REPORT NO. 39 PROBABLE MAXIMUM PRECIPITATION" IN THE HAWAllAN ISLANDS LOAN COPY (Nos. 6-22 Numbered Retroactively) *No: 1. Maximum possible precipitation over the Ompompanoos~c Basin above Union Villag~, Vt. 1943. *No. 2. Maximum possible precipitation over'the Ohio River-Basin above

149

Parameterized Algorithms for Directed Maximum Leaf Problems  

E-print Network

Parameterized Algorithms for Directed Maximum Leaf Problems Noga Alon 1 , Fedor V. Fomin 2 spanning tree, then D contains one with at least (n/2) 1/5 - 1 leaves. 1 Introduction The Maximum Leaf a digraph D, the Directed Maximum Leaf Out­Branching problem is the problem of finding an out­branching in D

Krivelevich, Michael

150

Dynamic reaching in infants during binocular and monocular viewing  

PubMed Central

This study examined reaching in 6-, 8-, and 10-month-olds during binocular and monocular viewing in a dynamic reaching situation. Infants were rotated toward a flat vertical board and reached for objects at one of seven positions along a horizontal line at shoulder height. Hand selection, time to contact the object, and reaching accuracy were examined in both viewing conditions. Hand selection was strongly dependent on object location, not infants’ age or whether one eye was covered. Monocular viewing and age did, however, affect time to object contact and contact errors: Infants showed longer contact times when one eye was covered, and 6-month-olds made more contact errors in the monocular condition. For right hand selection, contact times were longer when the covered right eye was leading during the chair rotation. For left hand selection, there were no differences in contact time due to whether the covered eye was leading during rotation. PMID:23771585

Ekberg, Therese L.; Rosander, Kerstin; von Hofsten, Claes; Olsson, Ulf; Soska, Kasey C.; Adolph, Karen E.

2014-01-01

151

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 ...

152

The pasta matrix reaching task: a simple test for measuring skilled reaching distance, direction, and dexterity in rats.  

PubMed

Skilled forelimb use has been used in many studies to examine motor system status, learning, and recovery from nervous system damage in rats. The dependent measures in many current skilled reaching models rely on endpoint measures, number of successful reaches, or qualitative measures, the movements used in performing a reach. The present study describes a new reaching task, which allows measurement of distance and direction of skilled forelimb movement while also permitting end point and qualitative measurements. Animals reached from a clear Plexiglas box through an aperture to retrieve pieces of straight, uncooked pasta from an array of 260 vertically oriented pieces of pasta arranged in rows distally and laterally away from the aperture (a matrix). By extending the range of a reach, more pasta is obtained. Limb movements, pieces of pasta removed, and the pattern of pasta removal are dependent measures. The usefulness of the test is demonstrated using control, dorsal column lesion, and unilateral dopamine depleted animals. The task uses a desired food, tests learning and skill, the range of limb movement, and the ability to reach for different distances and directions. The task can also be modified to investigate other features of limb use including skill adjustments, laterality, and force. PMID:11248339

Ballermann, M; Metz, G A; McKenna, J E; Klassen, F; Whishaw, I Q

2001-03-30

153

Turbo system for infant incubators to rapidly reach operating temperature  

Microsoft Academic Search

A neonatal incubator takes between 45 min to 90 min to reach operating temperature(25degC to 37degC). For emergency cases in hospitals incubators are kept on at operating temperature which implies high electricity consumption. We present a turbo system that allows incubators to reach operating temperature rapidly eliminating the need to keep incubators warm when not in use. We propose the

E. Barajas; C. Madariaga; A. Rodriguez; R. San Vicente; J. E. Chong-Quero

2009-01-01

154

REACH and reproductive and developmental toxicology: still questions.  

PubMed

Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH) is a new chemicals regulation law in the European Union (EU). The law is supplemented by tens of thousands of pages of guidance documents, and the implementation of REACH is still a work in progress. Requirements for chemical testing are based on the annual volume of a chemical or 'substance' that is produced or imported into the EU. These requirements include reproductive and developmental toxicity testing in experimental animals for an annual volume of 10 metric tonnes or more. However, under REACH, the testing in vertebrate animals may not be performed without permission, and the law encourages the use of alternative methods of filling data gaps on the toxicological properties of chemicals. These alternatives might include in vitro and structure-activity relationship studies, but the REACH technical guidance indicates that these kinds of studies are not adequate to replace reproductive and developmental toxicity testing in whole animals. The most practical opportunity for the avoidance of whole animal testing may be 'read-across,' a process in which gaps are filled using data from related compounds. A method called 'weight of evidence' under REACH may also be used to avoid whole animal reproductive and developmental toxicity testing based on existing data in regulation and non-regulation studies and based on factors such as chemical structure and anticipated exposure. It is also possible that thresholds of toxicological concerns will be accepted under REACH as a method to avoid vertebrate animal testing. PMID:22239083

Scialli, Anthony R; Guikema, Arnold J

2012-02-01

155

Project Completion Report on China's Room AC Reach Standard  

SciTech Connect

After much anticipation and hard work, China's reach standard for room air-conditioners was announced in September 2004, with the first tier going into effect on March 1, 2005 and the reach standard taking effect on January 1, 2009. This is a major milestone in the development of minimum energy efficiency standards in China: finally China has set a minimum standard that is meaningful and stringent. According to our preliminary analysis, the majority of room ACs products on the Chinese market in 2004 would not meet the 2009 reach standard requirement. In addition to setting the minimum requirement, China's new AC standard also include classification requirement for the newly established Energy Information Label, as well as the certification requirement for CECP's Energy Conservation Label. Highlights of the 2009 reach standard include: (1) The Chinese Reach Standard for Room AC in 2009 is tighter than American counterpart, and almost matches the efficiency of American Central Air-Conditioners; and (2) Summer peak demand reduction in 2020 due to the reach standard exceeds the capacity of the Three Gorges Project.

Lin, Jiang

2005-03-10

156

Visuospatial updating of reaching targets in near and far space.  

PubMed

The brain constructs multiple representations of near and far space but it is unclear which spatial mechanism guides reaching across eye movements in near space. Retinocentric reaching representations are known to exist in parietal cortex, but must be updated during eye movements, in order to remain accurate. In contrast, non-retinal (e.g. muscle-centered) reaching plans in motor cortex do not require updating, and so may provide a more stable encoding mechanism. To test between these, we employed a behavioral test. Subjects briefly foveated a target (located at various depths in near and far space) looked peripherally, then reached toward its remembered location. Surprisingly, subjects did not use the stable non-retinal reaching plan (compared to controls without eye movements). Instead, the intervening eye movements induced a systematic pattern of reaching errors for targets at all depths consistent with updating in a retinal frame. We conclude that a common eye-centered updating mechanism prevails in programming arm movements in both near and far space. PMID:11973460

Medendorp, W Pieter; Crawford, J Douglas

2002-04-16

157

The effect of shading during the reproductive stage on the growth and yield of two rice varieties grown at two levels of nitrogen fertility  

E-print Network

that under low light intensity and excess nitrogen stem growth predomi- nated. The work of Apaoan (3) and Bollich (6, 7) showed that rice plants grown under shade during the active vegetative stage ap- peared much taller but weaker than those shaded only...- requisite for nitrogen responsiveness. Photosynthesis and Carbohydrate Accumulation Yamada (42) showed that the photosynthetic rate of detached 25'C ' d 1th 1 d ligh ' ~- tensity reaching a maximum at about 50 t. o 60 Klux. These results suggested...

Lucas, Leandro Navarro

2012-06-07

158

Supermassive Black Hole Growth and Merger Rates from Cosmological N-body Simulations  

E-print Network

Understanding how seed black holes grow into intermediate and supermassive black holes (IMBHs and SMBHs, respectively) has important implications for the duty-cycle of active galactic nuclei (AGN), galaxy evolution, and gravitational wave astronomy. Most studies of the cosmological growth and merger history of black holes have used semianalytic models and have concentrated on SMBH growth in luminous galaxies. Using high resolution cosmological N-body simulations, we track the assembly of black holes over a large range of final masses -- from seed black holes to SMBHs -- over widely varying dynamical histories. We used the dynamics of dark matter halos to track the evolution of seed black holes in three different gas accretion scenarios. We have found that growth of Sagittarius A* - size SMBH reaches its maximum mass M_{SMBH}~10^6Msun at z~6 through early gaseous accretion episodes, after which it stays at near constant mass. At the same redshift, the duty-cycle of the host AGN ends, hence redshift z=6 marks the transition from an AGN to a starburst galaxy which eventually becomes the Milky Way. By tracking black hole growth as a function of time and mass, we estimate that the IMBH merger rate reaches a maximum of R_{max}=55 yr^-1 at z=11. From IMBH merger rates we calculate N_{ULX}=7 per Milky Way type galaxy per redshift in redshift range 2

Miroslav Micic; Kelly Holley-Bockelmann; Steinn Sigurdsson; Tom Abel

2007-03-20

159

Estimating morphological parameters of Tamarix ramosissima by Digital hemispherical image in the lower reaches of heihe river, northwest China  

Microsoft Academic Search

Tamarix ramosissima is a dominant shrub and mainly contributes to total biomass in the lower reaches of Heihe River. In order to study the biomass and growth status of the shrub, we need to measure the morphological parameters. Usually, the morphological parameters are measured by field survey. However, the method is low in efficient and accurate. In this study, the

Huanhua Peng; Chuanyan Zhao; Zhaodong Feng; Zhonglin Xu

2010-01-01

160

An investigation of the neural circuits underlying reaching and reach-to-grasp movements: from planning to execution  

PubMed Central

Experimental evidence suggests the existence of a sophisticated brain circuit specifically dedicated to reach-to-grasp planning and execution, both in human and non-human primates (Castiello, 2005). Studies accomplished by means of neuroimaging techniques suggest the hypothesis of a dichotomy between a “reach-to-grasp” circuit, involving the anterior intraparietal area, the dorsal and ventral premotor cortices (PMd and PMv – Castiello and Begliomini, 2008; Filimon, 2010) and a “reaching” circuit involving the medial intraparietal area and the superior parieto-occipital cortex (Culham et al., 2006). However, the time course characterizing the involvement of these regions during the planning and execution of these two types of movements has yet to be delineated. A functional magnetic resonance imaging study has been conducted, including reach-to-grasp and reaching only movements, performed toward either a small or a large stimulus, and Finite Impulse Response model (Henson, 2003) was adopted to monitor activation patterns from stimulus onset for a time window of 10 s duration. Data analysis focused on brain regions belonging either to the reaching or to the grasping network, as suggested by Castiello and Begliomini (2008). Results suggest that reaching and grasping movements planning and execution might share a common brain network, providing further confirmation to the idea that the neural underpinnings of reaching and grasping may overlap in both spatial and temporal terms (Verhagen et al., 2013). But, although responsive for both actions, they show a significant predominance for either one of the two actions and such a preference is evident on a temporal scale. PMID:25228872

Begliomini, Chiara; De Sanctis, Teresa; Marangon, Mattia; Tarantino, Vincenza; Sartori, Luisa; Miotto, Diego; Motta, Raffaella; Stramare, Roberto; Castiello, Umberto

2014-01-01

161

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

162

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

163

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. PMID:23382882

Himmelbach, Marc

2013-01-01

164

Effects of pictorial cues on reaching depend on the distinctiveness of target objects.  

PubMed

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. PMID:23382882

Christensen, Andrea; Borchers, Svenja; Himmelbach, Marc

2013-01-01

165

Engineering growth Undergraduates enrolled in Engineering reach all-time high  

E-print Network

of Engineering programme this year. This intake is not only the largest ever, but also includes record numbers As the engineering and construction industries learn valuable lessons from the Christchurch earthquakes, 18-year the earthquake compliance of historic buildings in the city. "We found a lot that aren't compliant. It's going

Auckland, University of

166

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

167

Neural Dynamics of Reaching Following Incorrect or Absent Motor Preparation  

PubMed Central

SUMMARY Moving is thought to take separate preparation and execution steps. While preparing, neural activity in primary motor and dorsal premotor cortices achieves a state specific to an upcoming action, but movements are not performed until the execution phase. We investigated whether this preparatory state (more precisely, prepare-and-hold state) is required for movement execution using two complementary experiments. We compared monkeys’ neural activity during delayed and non-delayed reaches, and in a delayed reaching task in which the target switched locations on a small percentage of trials. Neural population activity bypassed the prepare-and-hold state both in the absence of a delay and if the wrong reach was prepared. However, the initial neural response to the target was similar across behavioral conditions. This suggests that the prepare-and-hold state can be bypassed if needed, but there is a short-latency preparatory step which is performed prior to movement even without a delay. PMID:24462104

Ames, K. Cora; Ryu, Stephen I.; Shenoy, Krishna V.

2014-01-01

168

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

169

Telerobotic operation of structurally flexible, long-reach manipulators  

SciTech Connect

As a part of the Department of Energy`s Environmental Restoration and Waste Management Program, long-reach manipulators are being considered for the retrieval of waste from large storage tanks. Long-reach manipulators may have characteristics significantly different from those of typical industrial robots because of the flexibility of long links needed to cover the large workspace. To avoid structural vibrations during operation, control algorithms employing various types of shaping filters were investigated. A new approach that uses embedded simulation was developed and compared with others. In the new approach, generation of joint trajectories considering link flexibility was also investigated.

Kwon, D.S.; Hwang, D.H.; Babcock, S.M.

1994-09-01

170

Signal analysis using the maximum entropy method  

NASA Astrophysics Data System (ADS)

The analysis of discrete series is explained using the maximum entropy method in order to solve data processing problems in the aeroelastic study of wind turbines. Discrete Fourier spectrum and maximum entropy spectrum are compared. This method searches for an autoregressive model for a series containing a maximum of information about entropy. The autoregressive model is outlined and the notions 'information' and 'entropy' in signal analysis are defined. Energy and phase spectrum construction, starting from an autoregressive model, is described, with examples. The maximum entropy method is valuable where Fourier transformation techniques hardly work or fail.

Kuik, W.

1981-03-01

171

Duality in a maximum generalized entropy model  

NASA Astrophysics Data System (ADS)

This paper discusses a possible generalization for the maximum entropy principle. A class of generalized entropy is introduced by that of generator functions, in which the maximum generalized distribution model is explicitly derived including q-Gaussian distributions, Wigner semicircle distributions and Pareto distributions. We define a totally geodesic subspace in the total space of all probability density functions in a framework of information geometry. The model of maximum generalized entropy distributions is shown to be totally geodesic. The duality of the model and the estimation in the maximum generalized principle is elucidated to give intrinsic understandings from the point of information geometry.

Eguchi, Shinto; Komori, Osamu; Ohara, Atsumi

2015-01-01

172

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

173

Riparian shading and groundwater enhance growth potential for smallmouth bass in Ozark streams.  

PubMed

Moderation of stream temperatures by riparian shading and groundwater are known to promote growth and survival of salmonid fishes, but effects of riparian shade and groundwater on to be growth of warmwater stream fishes are poorly understood or assumed to be negligible. We used stream temperature models to relate shading from riparian vegetation and groundwater inflow to summer water temperatures in Missouri Ozark streams and evaluated effects of summer water temperatures on smallmouth bass, Micropterus dolomieu, growth using a bioenergetics model. Bioenergetics model simulations revealed that adult smallmouth bass in non-spring-fed streams have lower growth potential during summer than fish in spring-fed streams, are subject to mass loss when stream temperatures exceed 27 degrees C, and will likely exhibit greater interannual variation in growth during summer if all growth-influencing factors, other than temperature, are identical between the two stream types. Temperature models indicated that increased riparian shading will expand the longitudinal extent of thermal habitat capable of supporting adult smallmouth bass growth in spring-fed stream reaches when mean daily air temperatures exceed 27 degrees C. Optimum growth temperature (22 degrees C) will be present only in spring-fed streams under these conditions. Potential for increasing shade through riparian restoration is greatest for streams <5 m wide and along north-south reaches of larger streams. However, temperature models also indicated that restoring riparian shading to maximum levels throughout a watershed would increase the total stream mileage capable of supporting positive growth of adult smallmouth bass by only 1-6% when air temperatures are at or near average summer maxima; increases in suitable thermal habitat would be greatest in watersheds with higher spring densities. Riparian management for maintenance or restoration of the thermal habitat of adult smallmouth bass during summer should be focused in areas strongly influenced by groundwater. Restoring riparian shading along spring-fed warmwater streams will likely benefit adult smallmouth bass growth and may ultimately influence population sizes. PMID:16937811

Whitledge, Gregory W; Rabeni, Charles F; Annis, Gust; Sowa, Scott P

2006-08-01

174

Growth: Limits or Process?  

ERIC Educational Resources Information Center

The author argues that there are ways to change direction and avoid reaching limits to growth too soon. To do this, he suggests decentralization and modifications of federal, provincial, and corporate institutions. He proposes this to sensitize institutions to social and environmental costs, issues, and limits. (Author/MA)

Chambers, Al

1975-01-01

175

Erich Regener and the ionisation maximum of the atmosphere  

NASA Astrophysics Data System (ADS)

In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under water and in the atmosphere. Along with one of his students, Georg Pfotzer, he discovered the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be, largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students, and through his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

Carlson, P.; Watson, A. A.

2014-12-01

176

How Schools Can Recruit Hard-to-Reach Parents.  

ERIC Educational Resources Information Center

When embarking on school/community-based management, nine Hawaii elementary schools trained their staff in facilitative leadership and received technical assistance from district offices. Schools can involve more parents by reaching a shared understanding about parental involvement, developing appropriate involvement strategies, providing parents…

Aronson, Julie Z.

1996-01-01

177

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

178

Reaching for Dexterous Manipulation MIT EECS Area Exam  

E-print Network

1 Reaching for Dexterous Manipulation MIT EECS Area Exam Exam Committee: Rodney Brooks (chair. These three papers are good examples of mainstream work in dexterous manipulation. Following a brief review that many of the most ordinary things people do have also been the most difficult to replicate in our

179

Reaching out to the Community: A DPS Speakers' Bureau  

Microsoft Academic Search

One of the most frequent ways in which scientists reach out to the community is through public presentations, which are often informal and held at local schools, planetariums, and museums. These talks are usually arranged by personal contact between the scientist and a person at the host institution. We propose to facilitate these contacts by creating a voluntary DPS Speakers'

R. M. C. Lopes; L. Lebofsky; E. Miner; L. Lowes

2001-01-01

180

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 8 cm 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

181

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

1983-01-01

182

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

183

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

184

The role of kinematic redundancy in adaptation of reaching  

Microsoft Academic Search

Although important differences exist between learning a new motor skill and adapting a well-learned skill to new environmental constraints, studies of force field adaptation have been used frequently in recent years to identify processes underlying learning. Most of these studies have been of reaching tasks that were each hand position was specified by a unique combination of joint angles. At

Jeng-Feng Yang; John P. Scholz; Mark L. Latash

2007-01-01

185

Discrete time adaptive reaching law speed control of electrical drives  

Microsoft Academic Search

This paper describes an adaptive control scheme for servomotor speed control systems under inertial and frictional variations. The control is based on reaching law control (RLC), which is an approach to sliding mode control (SMC) design. The adaptations of the control parameters are performed using the gradient descent method. Discrete time implementation of the SMC strategy is considered in the

Z. H. Akpolat; M. Gokbulut

2003-01-01

186

Characteristics of ocean waters reaching Greenland's glaciers Fiammetta STRANEO,1  

E-print Network

Characteristics of ocean waters reaching Greenland's glaciers Fiammetta STRANEO,1 David A, Eugene, OR, USA 3 Center for Atmosphere­Ocean Science, New York University, New York, NY, USA 4 Climate Change Institute, University of Maine, Orono, ME, USA 5 Department of Earth Sciences, University

Johnson, Helen

187

REACH coarse-grained simulation of a cellulose fiber.  

PubMed

A molecular level understanding of the structure, dynamics and mechanics of cellulose fibers can aid in understanding the recalcitrance of biomass to hydrolysis in cellulosic biofuel production. Here, a residue-scale REACH (Realistic Extension Algorithm via Covariance Hessian) coarse-grained force field was derived from all-atom molecular dynamics (MD) simulations of the crystalline I? cellulose fibril. REACH maps the atomistic covariance matrix onto coarse-grained elastic force constants. The REACH force field was found to reproduce the positional fluctuations and low-frequency vibrational spectra from the all-atom model, allowing elastic properties of the cellulose fibril to be characterized using the coarse-grained force field with a speedup of >20 relative to atomistic MD on systems of the same size. The calculated longitudinal/transversal Young's modulus and the velocity of sound are in agreement with experiment. The persistence length of a 36-chain cellulose microcrystal was estimated to be ~380 ?m. Finally, the normal-mode analysis with the REACH force field suggests that intrinsic dynamics might facilitate the deconstruction of the cellulose fibril from the hydrophobic surface. PMID:22937726

Glass, Dennis C; Moritsugu, Kei; Cheng, Xiaolin; Smith, Jeremy C

2012-09-10

188

Suppose the USA had REACH: ramifications for formaldehyde  

Microsoft Academic Search

The Registration, Evaluation, and Authorization of Chemicals (REACH) legislation for regulating chemicals came into force in the EU in June 2007. This framework is stricter and more precautionary than its counterpart in the USA – the Toxic Substances Control Act – in that it requires data submissions for not only new but existing chemicals as well. This study evaluates the

Sara Hajiamiri; Myles T. Collins; John D. Graham

2010-01-01

189

Reach for the Stars: Visions for Literacy Coaching Programs  

ERIC Educational Resources Information Center

This brief by the Literacy Coaching Clearinghouse is about reaching for the stars--stories of vision and commitment from educators in small and large schools. Everyone knows of people who are held up as "visionaries" throughout history: Leonardo Da Vinci, Mahatma Gandhi, Jules Verne, Thomas Edison, Susan Anthony, or John Dewey, to name a few. The…

DeFord, Diane

2012-01-01

190

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

191

"Terms of Engagement" Not "Hard to Reach Parents"  

ERIC Educational Resources Information Center

This article presents findings of qualitative research commissioned by the Achievement for All project in a UK local authority. The research investigated how schools should engage parents, including those considered to be "hard to reach". A focus group methodology was adapted to enable parents to provide answers to the research questions. The…

Day, Sara

2013-01-01

192

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

193

Reaching First Year College Students: Current Practices in Instructional Programs  

ERIC Educational Resources Information Center

In light of the new emphasis on information literacy, this research updates previous studies and explores current practices in first year library instruction and programming. Academic librarians are reaching out to freshmen seminar programs, first year orientations, Introduction to College courses, and English composition courses to integrate…

Boyd-Byrnes, Mary Kate; McDermott, Dona

2006-01-01

194

Ethical Issues in Research with "Vulnerable" and "HardtoReach"  

E-print Network

Ethical Issues in Research with "Vulnerable" and "HardtoReach" PopulationsPopulations Emily E, and literature of research ethics without undergoing g g stringent certification. And yet the need for some ETHICS GUIDANCEKEY RESEARCH ETHICS GUIDANCE DOCUMENTS #12;Belmont ReportBelmont Report · A reaction

Illinois at Chicago, University of

195

Patterns of Arm Muscle Activation Involved in Octopus Reaching Movements  

E-print Network

it to perform many different movements, yet octopuses reach toward a tar- get in a stereotyped manner using studying arm movements. The difficulties lie in the so-called "inverse kinematics" and "inverse dynamics "inverse dynamic problem") (Bizzi et al., 1991; Flanders and Hermann, 1992). The complexity

Hochner, Binyamin

196

Reaching and Helping Unorganized and Disadvantaged People. Courier No. 33.  

ERIC Educational Resources Information Center

The articles in this issue are mainly concerned with how to reach the poorest and most disadvantaged sections of the population and how best to help once contact has been made. "Nijera Kori in Retrospect: In Search of an Organization of the Rural Poor" (Mohiuddin Ahmad) provides extracts from an evaluation of this grassroots, village-based,…

ASPBAE Courier, 1985

1985-01-01

197

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

198

DEPARTMENT OF TRANSPORTATION SERVICES University of Maryland Reaches Gold  

E-print Network

DEPARTMENT OF TRANSPORTATION SERVICES University of Maryland Reaches Gold The University of Maryland is awarded the gold level Bicycle Friendly University designation. October 22, 2014. Over the past Friendly University (BFU) program. One of only 10 schools to earn the gold level or higher designation

Lathrop, Daniel P.

199

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

200

The Development of Infants' Reaches for Stationary and Moving Targets.  

ERIC Educational Resources Information Center

Examined organization of 5.5, 8.5, and 11.5-month-olds' reaching skill for stationary and moving targets. Found that infants of all ages made anticipatory adjustments of hand alignment; effectiveness of these adjustments improved with age. Regardless of age, infants used dynamic information from spinning and oscillating targets to update ongoing…

Wentworth, Naomi; Benson, Janette B.; Haith, Marshall M.

2000-01-01

201

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

202

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

203

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 ...

204

Temporal and temperature effects on the maximum rate of rewarming from hibernation  

PubMed Central

During hibernation animals oscillate from near ambient (Ta) to euthermic body temperatures (Tb). As animals arouse, the rate of rewarming (RRW) might be expected to simply increase as a function of time. We monitored the Tb of golden-mantled ground squirrels (Spermophilus lateralis) housed at 4, 8, 12, and 16° C during natural arousals. The maximum RRW, the time required to reach a maximum RRW, and the relative time index all demonstrated negative relationships with Ta. The Tb corresponding to maximal RRW demonstrated a positive relationship with Ta. Squirrels reached maximal RRW when they had generated 30 to 40% of the heat required to reach a euthermic Tb. These data suggest that arousal is more constrained than expected and that both time and temperature influence the RRW. PMID:17948068

Utz, Jenifer C.; Velickovska, Vanja; Shmereva, Anastacia; van Breukelen, Frank

2007-01-01

205

Investigation of Ice Phenomena On The Hungarian Danube Reach  

NASA Astrophysics Data System (ADS)

The importance of scientific work in the field of ice floods is high on the southern Hungarian reach of the Danube. The most dangerous floods of the reach in the past were almost all icy. This used to be so for two main reasons, out of which one is a hydro-meteorological, the other is a morphological factor. River training works on the reach have been completed, only maintenance and small corrections are being done. In spite of the process of global warming, that can be concluded analyzing the past few decades' data, an unfortunate constellation of hydro-meteorological factors can anytime cause serious frosts, and, consequently, ice floods. In our study we statisti- cally analyzed the past hundred years' data series of the reach in question. The results proved the existence of a 30-years long, almost iceless period, that we investigated the reasons for. Because of the above-mentioned rare occurence of ice phenomena, the observation and study of these processes also deteriorated. It is a big luck that Hungarian experts have dealt a lot with past ice phenomena up to 1970. Starting out from literal data and ideas, our investigations and new observations can be massively based. The newest computer technology features are now used for ice observations on the southern Hungarian Danube reach. We could gain useful experience already in the winter of 2001-2002 in computer-aided ice observation (CAIO). In our presenta- tion we would like to give an overall impression about the current issues of CAIO in southern Hungary.

Keve, G.; Kontur, I.

206

Impact of LSP character on Slepton reach at the LHC  

NASA Astrophysics Data System (ADS)

Searches for supersymmetry at the Large Hadron Collider (LHC) have significantly constrained the parameter space associated with colored superpartners, whereas the constraints on color-singlet superpartners are considerably less severe. In this study, we investigate the dependence of slepton decay branching fractions on the nature of the lightest supersymmetric particle (LSP). In particular, in the Higgsino-like LSP scenarios, both decay branching fractions of and depend strongly on the sign and value of M 1 /M 2, which has strong implications for the reach of dilepton plus [InlineMediaObject not available: see fulltext.] searches for slepton pair production. We extend the experimental results for same flavor, opposite sign dilepton plus [InlineMediaObject not available: see fulltext.] searches at the 8TeV LHC to various LSP scenarios. We find that the LHC bounds on sleptons are strongly enhanced for a non-Bino-like LSP: the 95% C.L. limit for extends from 300 GeV for a Bino-like LSP to about 370 GeV for a Wino-like LSP. The bound for with a Higgsino-like LSP is the strongest (˜ 490 GeV) for M 1 /M 2 ˜ - tan2 ? W and is the weakest (˜ 220 GeV) for M 1 /M 2 ˜ tan2 ? W . We also calculate prospective slepton search reaches at the 14 TeV LHC. With 100 fb-1 integrated luminosity, the projected 95% C.L. mass reach for the left-handed slepton varies from 550 (670) GeV for a Bino-like (Winolike) LSP to 900 (390) GeV for a Higgsino-like LSP under the most optimistic (pessimistic) scenario. The reach for the right-handed slepton is about 440 GeV. The corresponding 5 ? discovery sensitivity is about 100 GeV smaller. For 300 fb-1 integrated luminosity, the reach is about 50 - 100 GeV higher.

Eckel, Jonathan; Ramsey-Musolf, Michael J.; Shepherd, William; Su, Shufang

2014-11-01

207

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2012 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...

2012-10-01

208

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

209

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2011 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...

2011-10-01

210

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

211

49 CFR 107.329 - Maximum penalties.  

Code of Federal Regulations, 2014 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...

2014-10-01

212

Maximum likelihood training of probabilistic neural networks  

Microsoft Academic Search

A maximum likelihood method is presented for training probabilistic neural networks (PNN's) using a Gaussian kernel, or Parzen window. The proposed training algorithm enables general nonlinear discrimination and is a generalization of Fisher's method for linear discrimination. Important features of maximum likelihood training for PNN's are: 1) it economizes the well known Parzen window estimator while preserving feedforward NN architecture,

Roy L. Streit; Tod E. Luginbuhl

1994-01-01

213

DISCRETE MAXIMUM ENTROPY ESTIMATORS FOR SPATIAL INTERPOLATION  

Microsoft Academic Search

This study applies the maximum entropy principle to develop estimators for spatial interpolation. Rather than continuous probability distributions commonly applied in the literature, this study tries to develop the estimators based on discrete probabilities. The maximum entropy estimators established include those random fields assuming second-order stationary and intrinsic hypothesis. For further comparison, this study also investigates both the random fields

Yuh-Ming Lee

214

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

215

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

216

Growth Problems  

MedlinePLUS

... a more normal growth pattern. Continue What Are Growth Disorders? Teens may have growth problems for other ... Most cases of dwarfism are genetic. Back Continue Growth Hormone Deficiency One growth disorder that is specific ...

217

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

218

Habitat and density-dependent growth of the sea urchin Paracentrotus lividus in Galicia (NW Spain)  

NASA Astrophysics Data System (ADS)

We studied the small-scale spatial variability in the growth of Paracentrotus lividus in two populations in Galicia (NW Spain) by reading growth rings. A tetracycline marking experiment was carried out to verify that the rings form annually. The growth rings were read by two independent readers in order to estimate the uncertainty involved in assigning the age. Of the six growth models evaluated (Tanaka, von Bertalanffy, Gompertz, Richards, logistic and Jolicoeur) the Tanaka function obtained the best fit to the data. This function predicts unlimited growth and a maximum growth rate of 15.00 (± 0.97 SE) mm·year- 1 at 3.09 ± 0.10 years old, which progressively decreases at older ages. However, habitat characteristics lead to intrapopulation variations in this general function. Recruitment seems to occur mainly in shallow waters (? 4 m) and when the sea urchins reach 50 mm (approximately 4 years old) they migrate to deeper areas. Sea urchins larger than 50 mm that stayed in shallow waters grew at a rate between 0.41 and 0.43 mm·year- 1 less than the sea urchins that moved to depths of 8 and 12 m. The population density also influenced the growth, and individuals older than 4 years had higher growth rates in high-density patches than in low-density areas. This could be due to the better environmental conditions in aggregation areas, that is, better protection against waves and predators and/or more abundant food.

Ouréns, Rosana; Flores, Luis; Fernández, Luis; Freire, Juan

2013-02-01

219

Estimating the seasonal maximum light use efficiency  

NASA Astrophysics Data System (ADS)

Light use efficiency (LUE) is a key parameter in estimating gross primary production (GPP) based on global Earth-observation satellite data and model calculations. In current LUE-based GPP estimation models, the maximum LUE is treated as a constant for each biome type. However, the maximum LUE varies seasonally. In this study, seasonal maximum LUE values were estimated from the maximum incident LUE versus the incident photosynthetically active radiation (PAR) and the fraction of absorbed PAR. First, an algorithm to estimate maximum incident LUE was developed to estimate GPP capacity using a light response curve. One of the parameters required for the light response curve was estimated from the linear relationship of the chlorophyll index and the GPP capacity at a high PAR level of 2000 (µmolm-2s-1), and was referred to as" the maximum GPP capacity at 2000". The relationship was determined for six plant functional types: needleleaf deciduous trees, broadleaf deciduous trees, needleleaf evergreen trees, broadleaf evergreen trees, C3 grass, and crops. The maximum LUE values estimated in this study displayed seasonal variation, especially those for deciduous broadleaf forest, but also those for evergreen needleleaf forest.

Muramatsu, Kanako; Furumi, Shinobu; Soyama, Noriko; Daigo, Motomasa

2014-11-01

220

Key design requirements for long-reach manipulators  

SciTech Connect

Long-reach manipulators differ from industrial robots and teleoperators typically used in the nuclear industry in that the aspect ratio (length to diameter) of links is much greater and link flexibility, as well as joint or drive train flexibility, is likely to be significant. Long-reach manipulators will be required for a variety of applications in the Environmental Restoration and Waste Management Program. While each application will present specific functional kinematic, and performance requirements an approach for determining the kinematic applicability and performance characteristics is presented, with a focus on waste storage tank remediation. Requirements are identified, kinematic configurations are considered, and a parametric study of link design parameters and their effects on performance characteristics is presented.

Kwon, D.S.; March-Leuba, S.; Babcock, S.M.; Hamel, W.R.

1993-09-01

221

Maximum spin of black holes driving jets  

NASA Astrophysics Data System (ADS)

Unbound outflows in the form of highly collimated jets and broad winds appear to be a ubiquitous feature of accreting black hole systems. The most powerful jets are thought to derive a significant fraction, if not the majority, of their power from the rotational energy of the black hole. Whatever the precise mechanism that causes them, these jets must, therefore, exert a braking torque on the black hole. Consequently, we expect jet production to play a significant role in limiting the maximum spin attainable by accreting black holes. We calculate the spin-up function - the rate of change of black hole spin normalized to the black hole mass and accretion rate - for an accreting black hole, accounting for this braking torque. We assume that the accretion flow on to a Kerr black hole is advection-dominated (ADAF) and construct easy-to-use analytic fits to describe the global structure of such flows based on the numerical solutions of Popham & Gammie. We find that the predicted black hole spin-up function depends only on the black hole spin and dimensionless parameters describing the accretion flow. Using recent relativistic magnetohydrodynamical (MHD) numerical simulation results to calibrate the efficiency of angular momentum transfer in the flow, we find that an ADAF flow will spin a black hole up (or down) to an equilibrium value of about 96 per cent of the maximal spin value in the absence of jets. Combining our ADAF system with a simple model for jet power, we demonstrate that an equilibrium is reached at approximately 93 per cent of the maximal spin value, as found in the numerical simulation studies of the spin-up of accreting black holes, at which point the spin-up of the hole by accreted material is balanced by the braking torque arising from jet production. The existence of equilibrium spin means that optically dim active galactic nuclei (AGNs) that have grown via accretion from an advection-dominated flow will not be maximally rotating. It also offers a possible explanation for the tight correlation observed by Allen et al. between the Bondi accretion rate and jet power in nine, nearby, X-ray luminous giant elliptical galaxies. We suggest that the black holes in these galaxies must all be rotating close to their equilibrium value. Our model also yields a relationship between jet efficiency and black hole spin that is in surprisingly good agreement with that seen in the simulation studies, indicating that our simple model is a useful and convenient description of ADAF inflow - jet outflow about a spinning black hole for incorporation in semi-analytic modelling as well as cosmological numerical simulation studies focusing on the formation and evolution of galaxies, groups and clusters of galaxies.

Benson, Andrew J.; Babul, Arif

2009-08-01

222

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

223

Motion quality evaluation of upper limb target-reaching movements  

Microsoft Academic Search

Fitts' Law was extended in the polar coordinate system, and a set of indices for human motion evaluation is proposed. In this paper, the index of difficulty and the index of performance are introduced as the general indices for the quality measure of plane target-to-target movement. As an example, the target-reaching movement of the upper limb, which is a basic

Nianfeng Yang; Ming Zhang; Changhua Huang; Dewen Jin

2002-01-01

224

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

225

DWDM Reach Extension of a GPON to 135 km  

NASA Astrophysics Data System (ADS)

We report the operation of a gigabit-capable passive optical network (GPON, 2.488 Gb/s downstream and 1.244 Gb/s upstream) over 135 km giving performance that is consistent with the standards of International Telecommunication Union-Telecommunications Standardization Sector (ITU-T). Advanced dense-wavelength-division-multiplexing (DWDM) equipment is used to extend the physical reach and to provide fiber gain.

Davey, Russell P.; Healey, Peter; Hope, Ian; Watkinson, Phil; Payne, Dave B.; Marmur, Oren; Ruhmann, Jörg; Zuiderveld, Yvonne

2006-01-01

226

On stiffening cables of a long reach manipulator  

SciTech Connect

A long reach manipulator will be used for waste remediation in large underground storage tanks. The manipulator`s slenderness makes it flexible and difficult to control. A low-cost and effective method to enhance the manipulator`s stiffness is proposed in this research by using suspension cables. These cables can also be used to accurately measure the position of the manipulator`s wrist.

Wang, S.L.; Santiago, P. [North Carolina A& T State Univ., Greensboro, NC (United States). Dept. of Mechanical Engineering

1996-02-01

227

Theory, guidance and applications on QSAR and REACH  

E-print Network

ways to describe the chemical. Foreword #12;Foreword VI The e-book on QSAR and REACH: Theory, guidance and applications With this eBook you will learn about the state of the QSAR art. This book composed of three parts to the statistical power of a model. This eBook aims to give you tools to evaluate when QSAR models can help further

Gini, Giuseppina

228

The leading joint hypothesis for spatial reaching arm motions.  

PubMed

The leading joint hypothesis (LJH), developed for planar arm reaching, proposes that the interaction torques experienced by the proximal joint are low compared to the corresponding muscle torques. The human central nervous system could potentially ignore these interaction torques at the proximal (leading) joint with little effect on the wrist trajectory, simplifying joint-level control. This paper investigates the extension of the LJH to spatial reaching. In spatial motion, a number of terms in the governing equation (Euler's angular momentum balance) that vanish for planar movements are non-trivial, so their contributions to the joint torque must be classified as net, interaction or muscle torque. This paper applies definitions from the literature to these torque components to establish a general classification for all terms in Euler's equation. This classification is equally applicable to planar and spatial motion. Additionally, a rationale for excluding gravity torques from the torque analysis is provided. Subjects performed point-to-point reaching movements between targets whose locations ensured that the wrist paths lay in various portions of the arm's spatial workspace. Movement kinematics were recorded using electromagnetic sensors located on the subject's arm segments and thorax. The arm was modeled as a three-link kinematic chain with idealized spherical and revolute joints at the shoulder and elbow. Joint torque components were computed using inverse dynamics. Most movements were 'shoulder-led' in that the interaction torque impulse was significantly lower than the muscle torque impulse for the shoulder, but not the elbow. For the few elbow-led movements, the interaction impulse at the elbow was low, while that at the shoulder was high, and these typically involved large elbow and small shoulder displacements. These results support the LJH and extend it to spatial reaching motion. PMID:23229774

Ambike, Satyajit; Schmiedeler, James P

2013-02-01

229

Physicians helping the underserved: the Reach Out program.  

PubMed

In the current health care environment of competition and market forces, concern has arisen that the classic principle of serving disadvantaged persons may not be fulfilled due to pressures from managed care. Reach Out, a $12 million national program of the Robert Wood Johnson Foundation, was developed to recruit leaders from among practicing physicians to organize projects to care for the uninsured and underserved. Physician volunteerism was a key component of all projects. Thirty-nine Reach Out projects were implemented and carried out across the United States, with average funding per project of $300000 distributed over a period of 4 years. Seven model types emerged, the most common of which, the free clinic and the referral network, accounted for two thirds of the total. At the program's conclusion, 199584 patients were enrolled and 11252 physicians recruited. Project execution was more complex than initially supposed, and major progress commonly was not evident until the third or fourth year, but at least two thirds of the projects are likely to continue with local support. With strong physician leadership and a funded administrative core, organized community efforts can develop and sustain an effective program. Programs such as Reach Out cannot solve the national problem of access to health care, but they can make a small but important impact on the number of uninsured and underserved persons without access to health care. PMID:10632287

Scott, H D; Bell, J; Geller, S; Thomas, M

2000-01-01

230

Dealing with target uncertainty in a reaching control interface.  

PubMed

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. PMID:24489788

Corbett, Elaine A; Körding, Konrad P; Perreault, Eric J

2014-01-01

231

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. PMID:24489788

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

2014-01-01

232

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

233

Optimising the Yield of Energy From Biomass by Analytical Models of the Rate of Growth  

NASA Astrophysics Data System (ADS)

In the reported study of growth-rates of grey alder (Alnus incana) stands at different quality sites the authors, as a continuation of an earlier study, propose and use analytical models to approximate experimental data of mean annual increments of standing stock. The model equations of growth-rate functions are further used to optimise the cutting age by minimising the total area of stands for sustainable annual supply of biomass. The growth-rate behaviour with the age of natural grey alder stands is described by an exponential function of three parameters defining the initial and the maximum growth-rates, and the age at which the growth-rate maximum is reached. None of the parameters is known from experiment, and they are found by least-square fit of the available experimental mean values appraised at the chosen time intervals into the model. A high correlation between the experimental data and the model function is found. The optimum cutting age of 18 years determined in the earlier study is confirmed. In farmed stands the growth-rate is made to continue increasing at a lower speed, and is well approximated by a linear function, in which case it is shown that the cutting age cannot be optimised with respect to the area minimum existing under the condition of a decreasing growth-rate after passing a maximum. In the case of a constant or slowly growing annual increment the authors suggest considering the ratio between the increment of stock per unit of the total area to the increase in the area. The overall efficiency of using the product of photosynthesis for a 20-year-old grey alder stand is roughly estimated to be 0.3%.

Abolins, J.; Gravitis, J.; Kosmacha, J.

2010-01-01

234

Quaternary history of the piedmont reach of Río Diamante, Argentina  

NASA Astrophysics Data System (ADS)

The Río Diamante is located in a segment of the southern Central Andes that is transitional in terms of morphology and foreland tectonics (33-37°S). The piedmont reach of the river flows eastwards between the main mountain front and the San Rafael Block (the southernmost foreland uplift to the east of the southern Central Andes). Unlike adjacent rivers, the Río Diamante has incised into pre-Quaternary bedrock to form a deep canyon across the piedmont. Five fill and strath terraces were mapped, correlated, and surveyed along the ˜35 km piedmont reach to determine their paleo-long profiles. Chronological data for the terraces were provided by geochemical correlation of interbedded tephras to a previously dated ignimbrite, as well as by eight cosmogenic 10Be ages, and suggest a synchronous relationship between fill terrace deposition and glaciation upstream. Terraces are tentatively correlated with oxygen isotope stages 16 (Qt1), 12 (Qt2), 4 (Qt3) and 2 (Qt4 and Qt5). Minor spatial variation in incision along the reach is apparent from the long profile of the Qt2 strath (˜450 ka), which shows low-amplitude folding. The long-term reach average rate of bedrock incision is estimated to be ˜0.1-0.5 m/kyr and the recent shorter term (post-OIS 2) rate is estimated at ˜2 m/kyr. Mid and late Quaternary uplift of the piedmont area is a likely cause for the incision; however, other possible explanations include a delayed response to pre-mid Quaternary uplift, or a response to changes in climate and sediment supply on a tectonically stable portion of the piedmont flanked by subsiding basins. Base-level fall due to subsidence on the eastern side of the San Rafael Block creating a westward migrating knickzone may have contributed to the incision, but the depth of incision is greater than the observed subsidence and no major knickzone is present in the modern river profile of the study reach. Studies such as this on piedmont geomorphic processes are important for understanding the topographic and tectonic transitions that characterise the southern Central Andes.

Baker, Sophie E.; Gosse, John C.; McDonald, Eric V.; Evenson, Edward B.; Martínez, Oscar

2009-07-01

235

The Bacterial Growth Curve.  

ERIC Educational Resources Information Center

A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)

Paulton, Richard J. L.

1991-01-01

236

14 CFR 65.47 - Maximum hours.  

Code of Federal Regulations, 2011 CFR

...CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours. Except in an emergency, a certificated air traffic control tower operator must be relieved of all duties...

2011-01-01

237

14 CFR 65.47 - Maximum hours.  

Code of Federal Regulations, 2014 CFR

...CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours. Except in an emergency, a certificated air traffic control tower operator must be relieved of all duties...

2014-01-01

238

14 CFR 65.47 - Maximum hours.  

Code of Federal Regulations, 2012 CFR

...CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours. Except in an emergency, a certificated air traffic control tower operator must be relieved of all duties...

2012-01-01

239

14 CFR 65.47 - Maximum hours.  

Code of Federal Regulations, 2013 CFR

...CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours. Except in an emergency, a certificated air traffic control tower operator must be relieved of all duties...

2013-01-01

240

14 CFR 65.47 - Maximum hours.  

Code of Federal Regulations, 2010 CFR

...CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Air Traffic Control Tower Operators § 65.47 Maximum hours. Except in an emergency, a certificated air traffic control tower operator must be relieved of all duties...

2010-01-01

241

Raman self-focusing at maximum coherence  

NASA Astrophysics Data System (ADS)

We demonstrate a type of Raman self-focusing and -defocusing that is inherent in operation at maximum coherence. In this regime the two-photon detuning from the Raman resonance controls the refractive index of the medium.

Walker, D. R.; Yavuz, D. D.; Shverdin, M. Y.; Yin, G. Y.; Sokolov, A. V.; Harris, S. E.

2002-12-01

242

Temporal dynamics of non-structural carbohydrates and xylem growth in Pinus sylvestris exposed to drought  

PubMed Central

Wood formation requires a continuous supply of carbohydrates for structural growth and metabolism. In the montane belt of the central Austrian Alps we monitored the temporal dynamics of xylem growth and non-structural carbohydrates (NSC) in stem sapwood of Pinus sylvestris L. during the growing season 2009, which was characterized by exceptional soil dryness within the study area. Soil water content dropped below 10 % at the time of maximum xylem growth end of May. Histological analyses have been used to describe cambial activity and xylem growth. Determination of NSC was performed using specific enzymatic assays revealing that total NSC ranged from 0.8 to 1.7 % dry matter throughout the year. Significant variations (P < 0.05) of the size of the NSC pool were observed during the growing season. Starch showed persistent abundance throughout the year reaching a maximum shortly before onset of late wood formation in mid-July. Seasonal dynamics of NSC and xylem growth suggest that (i) high sink activity occurred at start of the growing season in spring and during late wood formation in summer and (ii) there was no particular shortage in NSC, which caused P. sylvestris to draw upon stem reserves more heavily during drought in 2009. PMID:22003262

Oberhuber, Walter; Swidrak, Irene; Pirkebner, Daniela; Gruber, Andreas

2011-01-01

243

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

244

Effect of Temperature on Growth of Vibrio paraphemolyticus and Vibrio vulnificus in Flounder, Salmon Sashimi and Oyster Meat  

PubMed Central

Vibrio parahaemolyticus and Vibrio vulnificus are the major pathogenic Vibrio species which contaminate ready-to-eat seafood. The purpose of this study was to evaluate the risk of human illness resulting from consumption of ready-to-eat seafood such as sashimi and raw oyster meat due to the presence of V. parahaemolyticus and V. vulnificus. We compared the growth kinetics of V. parahaemolyticus and V. vulnificus strains in broth and ready-to-eat seafood, including flounder and salmon sashimi, as a function of temperature. The growth kinetics of naturally occurring V. vulnificus in raw oyster meat was also evaluated. The minimum growth temperatures of V. parahaemolyticus and V. vulnificus in broth were 13 °C and 11 °C, respectively. Overall, significant differences in lag time (LT) and specific growth rate (SGR) values between flounder and salmon sashimi were observed at temperatures ranging from 13 °C to 30 °C (p < 0.05). The growth of naturally occurring V. vulnificus reached stationary phase at ~4 log CFU/g in oysters, regardless of the storage temperature. This data indicates that the population of V. vulnificus in oysters did not reach the maximum population density as observed in the broth, where growth of V. vulnificus and V. parahaemolyticus isolated from oysters grew up to >8 log CFU/mL. PMID:23330227

Kim, Yoo Won; Lee, Soon Ho; Hwang, In Gun; Yoon, Ki Sun

2012-01-01

245

Radionuclide concentrations in white sturgeons from the Hanford Reach of the Columbia River  

SciTech Connect

We summarized radionuclide concentrations in white sturgeons Acipenser transmontanus from the Columbia River during a period when several plutonium-production reactors were operating at the Hanford Site in Washington State and compared these values to those measured several years after reactor shutdown. Studies conducted in the Hanford Reach of the Columbia River during 1953-1955 indicated that high concentrations of radionuclides (as total beta) were present in some internal organs on the external surface of white sturgeons. Average concentrations were about 1,480 Bq/kg for liver and kidney and exceeded 2,200 Bq/kg for fins and scutes. The principal radionuclides in the tissues of white sturgeons from the Hanford Reach during 1963-1967, the peak reactor operation interval, were [sup 32]P, [sup 65]Zn, and [sup 51]Cr. Average concentrations of [sup 32]P in muscle ranged from 925 to 2,109 Bq/kg and were typically two to seven times greater than [sup 65]Zn. Average concentrations of radionuclides were usually in the order of gut contents [much gt] carcass > muscle. Studies from 1989 to 1990 showed that radionuclide concentrations had decreased dramatically in white sturgeon tissue since the time of reactor operation. Maximum concentrations for artificial radionuclides ([sup 90]Sr, [sup 60]Co, [sup 137]Cs) in muscle and cartilage of white sturgeons in the Columbia River had declined to less than 4 Bq/kg. Formerly abundant radionuclides, including [sup 32]P, [sup 65]Zn, and [sup 51]Cr, could not be detected in recent tissue samples. Further, radionuclide tissue burden in populations of sturgeons from the Hanford Reach and the upstream or downstream reference locations did not differ significantly. 34 refs., 3 figs., 4 tabs.

Dauble, D.D.; Poston, T.M. (Pacific Northwest Lab., Richland, WA (United States))

1994-07-01

246

Defining a controller architecture for the Long-Reach Manipulator  

SciTech Connect

To draft a procurement specification for the Long-Reach Manipulator (LRM), the benefits and limitations of the various robotic control system architectures available need to be determined. This report identifies and describes the advantages and potential disadvantages of using an open control system versus a closed (or proprietary) system, focusing on integration of interfaces for sensors, end effectors, tooling, and operator interfaces. In addition, the various controls methodologies of several recent systems are described. Finally, the reasons behind the recommendation to procure an open control system are discussed.

Ford, W.E. [Sandia National Labs., Albuquerque, NM (United States). Intelligent Systems Dept. III

1994-06-01

247

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

248

Energy Reduction Projects to Help Nissan Reach BBBP Goals  

E-print Network

Energy Reduction Projects to Help Nissan Reach BBBP Goals Brett Rasmussen, PE, CEM Senior Energy Engineer Nissan North America May 23, 2013 ESL-IE-13-05-38 Proceedings of the Thrity-Fifth Industrial Energy Technology Conference New Orleans..., LA. May 21-24, 2013 ? ? ? Smyrna, TN Decherd, TN Canton, MS NISSAN?S U.S. PLANTS 2 ESL-IE-13-05-38 Proceedings of the Thrity-Fifth Industrial Energy Technology Conference New Orleans, LA. May 21-24, 2013 Bill Kruger Signs the Save Energy Now...

Rasmussen, B.

2013-01-01

249

Open Learning in India: Evolution, Diversification and Reaching Out  

ERIC Educational Resources Information Center

Distance education has a history of over four decades in India. There has been a vast growth in the number of learners who need education and thus also the corresponding channels of providing education. Due to the constraints of the traditional educational sector, open and distance learning has been found to be a workable alternative strategy in…

Sharma, Ramesh C.

2005-01-01

250

two stream reaches on the Northeastern Shore of Lake Tanganyika  

E-print Network

Water provides invaluable services to humanity including drinking water, waste dilution, fisheries, irrigation, and power generation (Wetzel 2001). However the exponential growth of human population puts a severe strain on this finite resource. Agricultural, pastoral, building, and industrial activities tend to

unknown authors

251

Guide to pediatric services Helping children reach their full potential  

E-print Network

, including stem-cell transplants n Cardiology and cardiac surgery n Chest surgery n Child and adolescent psychiatry n Child development and behavior n Child neurology n Child protection n Critical-care medicine n growth and development. Child life specialists, along with music and art therapists, provide bedside play

Leistikow, Bruce N.

252

Possible dynamical explanations for Paltridge's principle of maximum entropy production  

NASA Astrophysics Data System (ADS)

Throughout the history of non-equilibrium thermodynamics a number of theories have been proposed in which complex, far from equilibrium flow systems are hypothesised to reach a steady state that maximises some quantity. Perhaps the most celebrated is Paltridge's principle of maximum entropy production for the horizontal heat flux in Earth's atmosphere, for which there is some empirical support. There have been a number of attempts to derive such a principle from maximum entropy considerations. However, we currently lack a more mechanistic explanation of how any particular system might self-organise into a state that maximises some quantity. This is in contrast to equilibrium thermodynamics, in which models such as the Ising model have been a great help in understanding the relationship between the predictions of MaxEnt and the dynamics of physical systems. In this paper we show that, unlike in the equilibrium case, Paltridge-type maximisation in non-equilibrium systems cannot be achieved by a simple dynamical feedback mechanism. Nevertheless, we propose several possible mechanisms by which maximisation could occur. Showing that these occur in any real system is a task for future work. The possibilities presented here may not be the only ones. We hope that by presenting them we can provoke further discussion about the possible dynamical mechanisms behind extremum principles for non-equilibrium systems, and their relationship to predictions obtained through MaxEnt.

Virgo, Nathaniel; Ikegami, Takashi

2014-12-01

253

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

254

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

255

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

256

24 CFR 941.306 - Maximum project cost.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 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...

2013-04-01

257

40 CFR 141.13 - Maximum contaminant levels for turbidity.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 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...

2010-07-01

258

40 CFR 141.65 - Maximum residual disinfectant levels.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Maximum residual disinfectant levels. 141.65 Section 141...Contaminant Levels and Maximum Residual Disinfectant Levels § 141.65 Maximum residual disinfectant levels. (a) Maximum residual...

2010-07-01

259

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

260

Mouth Growths  

MedlinePLUS

... Symptoms of Oral and Dental Disorders 4 Mouth Growths Growths can originate in any type of tissue ... be Noncancerous (benign) Precancerous (dysplastic) Cancerous (malignant) Noncancerous growths: Most mouth growths are noncancerous. A variety of ...

261

Growth Disorders  

MedlinePLUS

... today's doctors have learned about growth. What's a Growth Disorder? Everyone grows and matures differently. You may ... than other kids the same age. What's Normal Growth? If growth isn't the same for all ...

262

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

263

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

264

Google Hangouts: Leveraging Social Media to Reach the Education Community  

NASA Astrophysics Data System (ADS)

Research shows that educator professional development is most effective when it is sustained and/or when a follow-on component is included to support the learning process. In order to create more comprehensive learning experiences for our workshop participants, the education team at the Space Telescope Science Institute is working collaboratively with scientific staff and other experts to create a follow-on component for our professional development program. The new component utilizes video conferencing platforms, such as Google's Hangouts On Air, to provide educators with content updates and extended learning opportunities in between in-person professional development experiences. The goal is to enhance our professional development program in a cost-effective way while reaching a greater cross-section of educators. Video broadcasts go live on Google+, YouTube, and our website - thus providing access to any user with a web browser. Additionally, the broadcasts are automatically recorded and archived for future viewing on our YouTube channel. This provides educators with anywhere, anytime training that best suits their needs and schedules. This poster will highlight our new Hangouts for educators as well as our cross-departmental efforts to expand the reach of our Hubble Hangouts for the public through a targeted recruitment strategy.

Eisenhamer, Bonnie; Summers, Frank; McCallister, Dan; Ryer, Holly

2015-01-01

265

Comparing cerebellar and motor cortical activity in reaching and grasping.  

PubMed

The activity of single cells in the cerebellar and motor cortex of awake monkeys was recorded during separate studies of whole-arm reaching movements and during the application of force-pulse perturbations to hand-held objects. Two general observations about the contribution of the cerebellum to the control of movement emerge from the data. The first, derived from the study of whole arm reaching, suggests that although both the motor cortex and cerebellum generate a signal related to movement direction, the cerebellar signal is less precise and varies from trial to trial even when the movement kinematics remain unchanged. The second observation, derived from the study of predictable perturbations of a hand-held object, indicates that cerebellar cortical neurons better reflect preparatory motor strategies formed from the anticipation of cutaneous and proprioceptive stimuli acquired by previous experience. In spite of strong relations to grip force and receptive fields stimulated by preparatory grip forces increase, the neurons of the percentral motor cortex showed very little anticipatory activity compared with either the premotor areas or the cerebellum. PMID:8334592

Smith, A M; Dugas, C; Fortier, P; Kalaska, J; Picard, N

1993-05-01

266

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

267

An optically trapped mirror for reaching the standard quantum limit  

E-print Network

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.

Nobuyuki Matsumoto; Yuta Michimura; Yoichi Aso; Kimio Tsubono

2014-05-19

268

Using maximum likelihood to estimate population size from temporal changes in allele frequencies.  

PubMed Central

We develop a maximum-likelihood framework for using temporal changes in allele frequencies to estimate the number of breeding individuals in a population. We use simulations to compare the performance of this estimator to an F-statistic estimator of variance effective population size. The maximum-likelihood estimator had a lower variance and smaller bias. Taking advantage of the likelihood framework, we extend the model to include exponential growth and show that temporal allele frequency data from three or more sampling events can be used to test for population growth. PMID:10353915

Williamson, E G; Slatkin, M

1999-01-01

269

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

270

Cell development obeys maximum Fisher information  

E-print Network

Eukaryotic cell development has been optimized by natural selection to obey maximal intracellular flux of messenger proteins. This, in turn, implies maximum Fisher information on angular position about a target nuclear pore complex (NPR). The cell is simply modeled as spherical, with cell membrane (CM) diameter 10 micron and concentric nuclear membrane (NM) diameter 6 micron. The NM contains about 3000 nuclear pore complexes (NPCs). Development requires messenger ligands to travel from the CM-NPC-DNA target binding sites. Ligands acquire negative charge by phosphorylation, passing through the cytoplasm over Newtonian trajectories toward positively charged NPCs (utilizing positive nuclear localization sequences). The CM-NPC channel obeys maximized mean protein flux F and Fisher information I at the NPC, with first-order delta I = 0 and approximate 2nd-order delta I = 0 stability to environmental perturbations. Many of its predictions are confirmed, including the dominance of protein pathways of from 1-4 proteins, a 4nm size for the EGFR protein and the approximate flux value F =10^16 proteins/m2-s. After entering the nucleus, each protein ultimately delivers its ligand information to a DNA target site with maximum probability, i.e. maximum Kullback-Liebler entropy HKL. In a smoothness limit HKL approaches IDNA/2, so that the total CM-NPC-DNA channel obeys maximum Fisher I. Thus maximum information approaches non-equilibrium, one condition for life.

B. R. Frieden; R. A. Gatenby

2014-04-29

271

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

272

Published by ORNL's Energy Efficiency and Renewable Energy Program (www.ornl.gov/Energy_Eff) November 1998 ORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State  

E-print Network

Published by ORNL's Energy Efficiency and Renewable Energy Program (www.ornl.gov/Energy_Eff) November 1998 ORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State Energy AgenciesORNL Reaches Out to State

Pennycook, Steve

273

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

274

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. PMID:21330552

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

2011-01-01

275

Soybean Seed Water Relations during in Situ and in Vitro Growth and Maturation.  

PubMed

Water, osmotic, and pressure potentials of soybean (Glycine max [L.] Merrill) embryos and related maternal tissues were measured during periods of seed growth and maturation to test the involvement of embryo water relations in seed maturation. Seeds were matured in situ or in an in vitro liquid culture medium in detached pods or as isolated seeds. Changes in water relations of embryo tissues were independent of maternal tissues. During seed maturation in situ, water and osmotic potentials in both embryo and maternal tissues declined sharply near the time of maximum dry weight. During in vitro seed culture with and without pods, water and osmotic potentials in axis and cotyledon tissues declined continuously during growth. Water and osmotic potentials of the seed coat, which was present only during in vitro seed culture with pods, changed little during the culture period. Positive turgor in the embryo was maintained beyond maximum dry weight and the loss of green color during in vitro culture but declined to zero at maturity in situ. The osmotic potential in embryo tissues declined from -1.1 megapascals at early pod fill to between -1.65 and -2.2 megapascals at maximum seed dry weight across all maturation environments. It is suggested that the decreasing osmotic potential in the growing soybean embryo reaches a threshold level that is associated with cessation of growth and onset of seed maturation. PMID:16666590

Saab, I N; Obendorf, R L

1989-02-01

276

Factors affecting the age-C resident fish community along shorelines of the Hanford Reach of the Columbia River  

USGS Publications Warehouse

The Hanford Reach is one of the few remaining unimpounded sections of the Columbia River. However, because of flow management at upstream dams, there are often large fluctuations in water level. To determine how environmental conditions might affect age-0 resident fishes in the Hanford Reach, we evaluated species composition, distribution, abundance, and standard lengths of larval and juvenile fishes along shoreline habitats during July and August 1998, 1999, and 2000. Catches in beach seine hauls during all three years were highly variable. The four most abundant taxa collected were three cyprinids, peamouth (Mylocheilus caurinus), northern pikeminnow (Plychocheilus oregonensis), and redside shiner (Richardson ius balteatus); and suckers (Catostoinus spp.). Highest overall catches were in sloughs of the Hanford Reach in 1999, a year with high flows, lower water level fluctuations, and more vegetation. Mean shoreline summer water temperatures were higher in 1998 than in 1999 and 2000, and mean lengths of the four most abundant taxa in late August were also greater in 1998, due presumably to enhanced growth or an earlier spawning season. In spite of flow fluctuations, overall catches of age-0 resident fishes were greater in the riverine Hanford Reach compared to past catches in a more lentic Columbia River reservoir. High abundances of age-0 resident fishes in the Hanford Reach could be due to more spawning and rearing habitat in this structurally complex area, and may mitigate for negative effects of variable flow regimes.

Gadomski, D.M.; Wagner, P.G.

2009-01-01

277

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

278

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

279

Learning of scaling factors and reference axes for reaching movements.  

PubMed

TO further understand visuomotor transformations in reaching, we compared adaptation to display rotation and altered gain in planar movements. Healthy subjects moved a cursor on a screen by moving an indicator on a horizontal digitizing tablet with their unseen hand. Adaptation to rotation was less complete and was accompanied by markedly increased directional variability. Adaptation training on a single target generalized broadly for gain change, but poorly for rotation. We propose that the difficulty in adapting to rotation arises from the substantial demands on short-term working memory imposed by the need to determine the new reference direction. Adaptation to gain change makes more modest demands on short-term memory to recalibrate the visuomotor scaling factor. PMID:8951852

Pine, Z M; Krakauer, J W; Gordon, J; Ghez, C

1996-10-01

280

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

281

Coding of the reach vector in parietal area 5d.  

PubMed

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. PMID:22841318

Bremner, Lindsay R; Andersen, Richard A

2012-07-26

282

Bell Atlantic and Communications Workers of America (CWA) Reach Agreement  

NSDL National Science Digital Library

This week's In the News examines the recent labor dispute between the Bell Atlantic Corporation and the Communications Workers of America (CWA). The ten resources discussed provide background information on the telecommunications industry and press coverage of the August 9-11, 1998 strike as well as Bell Atlantic's corporate history. Adding a human dimension to typical technological and economic coverage of the telecommunications industry, 73,000 telephone workers paralyzed Bell Atlantic services in thirteen Eastern states on August 9, 1998. Union fear concerning Bell Atlantic's recent acquisition of GTE is cited as a major strike cause as job losses due to new Internet technologies became a reality following the merger. A tentative two-year agreement was reached on August 11, however, ending the conflict with the promise of "high-skill, good paying jobs" that allow workers to reap the benefits of information-age ventures as well as employers.

Waters, Megan.

283

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

284

Relationship between improvements in motor performance and changes in anticipatory postural adjustments during whole-body reaching training.  

PubMed

Anticipatory postural adjustments (APAs) provide postural stability and play an important role in ensuring appropriate motor performance. APAs also change in various situations. However, it is unknown whether changes in APAs during repetitive movement training contribute to improvement in motor performance. This study aimed to investigate the relationship between improvement in motor performance and changes in APAs during repeated reaching training, as well as the learning effects on APA changes. Sixteen healthy subjects (23 ± 2 years of age) stood barefoot on a force platform and reached as quickly and accurately as possible to a target placed at their maximum reach distance immediately following a beep signal in a reaction time condition. Whole-body reaching training with the right arm was repeated 100 times for three consecutive days. Motor performance and APAs were evaluated on the first day, after discontinuation of training for one day, and again at three months. In addition, reaching with the left arm (untrained limb) was tested on the first and the fifth training day. Body position segments were measured using three-dimensional motion analysis. Surface electromyography of eight postural muscles in both lower limbs was recorded. Kinetics data were recorded using the force platform. Whole-body reaching training induced not only improvements in motor performance (e.g., increased peak hand velocity), but also changes in APAs (e.g., earlier APA onset and increased amplitude). These changes were strongly correlated with and occurred earlier than improvements in motor performance. The learning effects on APAs were retained after the discontinuation of training and were generalized to the untrained limb. These results suggest that change in APAs contributes to improvement in motor performance; that is, the central nervous system may be able to adapt APAs for improvement in motor performance. PMID:25108269

Saito, Hiroshi; Yamanaka, Masanori; Kasahara, Satoshi; Fukushima, Junko

2014-10-01

285

Variability in the timing of the late Holocene maximum extent of the southwest Greenland Ice Sheet  

NASA Astrophysics Data System (ADS)

Boreal summer climate generally cooled across the mid to late Holocene, driving growth of the Greenland Ice Sheet. The timing of maximum late Holocene Greenland Ice Sheet extent is usually assigned to the Little Ice Age (LIA), although earlier more extensive Neoglacial advances may have occurred. Here we present new 10-Be surface exposure ages from erratic boulders on bedrock just outside of historical moraines deposited during the LIA near Kangerlussuaq, Paamiut and Narsarsuaq in southwest Greenland to date when ice was more extensive than during the LIA. A more extensive Neoglacial advance at ~2 ka was previously proposed near Kangerlussuaq. Our cosmogenic dates just outside the historical moraine at Kangerlussuaq indicate, however, that ice has been within its historical limit since 6.8±0.1 ka (n=6, 1 std. error), which is similar to recently published age constraints further north in the Disko Bugt region of west Greenland. Near Narsarsuaq in south Greenland, cosmogenic boulder dates indicate that at 1.2±0.2 ka (n=4, 1 std. error), the outlet glacier Kiagtût sermiat was ~200 m thicker than its historical limit. The timing of thicker ice near Narsarsuaq is likely concurrent with an ~8 km advance the same outlet glacier relative to the modern ice margin previously inferred from one minimum limiting radiocarbon date of 1.2±0.1 ka (1?). Cosmogenic dates from near Paamiut in southwest Greenland and additional Narsarsuaq dates are forthcoming. The timing of ice thinning and retreat near Narsarsuaq beginning at ~1.2 ka is concurrent with a switch from the dominance of Arctic- to Atlantic-sourced water masses within southern Greenland fjords, inferred from changes in fjord faunal assemblages. Modern switches in the source of fjord waters are related to variations in the North Atlantic Oscillation (NAO), with a switch from a positive to a negative phase causing the incursion of relatively warm Irminger Current waters around southern Greenland. We hypothesize that similar variations in North Atlantic atmospheric-oceanic circulation at centennial time-scales could have resulted in relatively cold southern Greenland fjord waters prior to ~1.2 ka during a positive NAO-like state, which forced a more extensive Neoglacial advance in southern Greenland than during the LIA. Conversely, during the LIA, warmer Atlantic waters may have dominated southern Greenland fjords, resulting in less extensive ice. The importance of this effect may have diminished northward up the coast, such that at Kangerlussuaq and further north, temperatures reached Holocene minima and the ice sheet margin its Holocene maximum extent during the LIA.

Carlson, A. E.; Winsor, K.; Ullman, D. J.; Murray, D. S.; Rood, D. H.; Axford, Y.

2011-12-01

286

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

287

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

288

Pointing at Maximum Power for PV  

NSDL National Science Digital Library

Student teams measure voltage and current in order to determine the power output of a photovoltaic (PV) panel. They vary the resistance in a simple circuit connected to the panel to demonstrate the effects on voltage, current, and power output. After collecting data, they calculate power for each resistance setting, creating a graph of current vs. voltage, and indentifying the maximum power point.

Integrated Teaching And Learning Program

289

: runout specimen max : maximum fatigue stress  

E-print Network

: runout specimen max : maximum fatigue stress fe,i : elastic limit strength of each specimen 750 uniaxial tensile fatigue stress. Interests in tensile fatigue strength and behaviour come from the fact.g. cantilever of bridge deck slab). Tensile Fatigue behaviour of UHPFRC Doctoral student: Tohru Makita

290

Maximum rotation frequency of strange stars  

SciTech Connect

Using the MIT bag model of strange-quark matter, we calculate the maximum angular frequency of the uniform rotation of strange stars. After studying a broad range of the MIT bag-model parameters, we obtain an upper bound of 12.3 kHz.

Zdunik, J.L.; Haensel, P. (Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, PL-00-716 Warsaw (Poland))

1990-07-15

291

MODIFIED ALSEP Maximum Antenna Pointing Error  

E-print Network

and high rates of 91 600 and 101 600 bps. The MSFN ground stations are considered to have either cooled angle and possible surface moon slopes could then cause a small amount of multipath signal cancellation°, the third side lobe will reflect from the moon's surface also with a 35° angle. The maximum loss from

Rathbun, Julie A.

292

Maximum Galactic Disks vs. Hot Dark Halos  

E-print Network

A series of arguments is presented for heavy galaxy disks not only in the optical regions, but also in the dark matter dominated regions of spirals. We are testing this possibility with extreme maximum disk N-body models without any conventional spheroidal dark halo.

Daniel Pfenniger

2000-09-04

293

Weak Scale From the Maximum Entropy Principle  

E-print Network

The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\\cal{O}}(300\\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \\begin{equation} v_{h}\\sim\\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\

Yuta Hamada; Hikaru Kawai; Kiyoharu Kawana

2014-09-23

294

Integrated photovoltaic maximum power point tracking converter  

Microsoft Academic Search

A low-power low-cost highly efficient maximum power point tracker (MPPT) to be integrated into a photovoltaic (PV) panel is proposed. This can result in a 25% energy enhancement compared to a standard photovoltaic panel, while performing functions like battery voltage regulation and matching of the PV array with the load. Instead of using an externally connected MPPT, it is proposed

Johan H. R. Enslin; Mario S. Wolf; D. B. Snyman; Wernher Swiegers

1997-01-01

295

Comparing maximum pressures in internal combustion engines  

NASA Technical Reports Server (NTRS)

Thin metal diaphragms form a satisfactory means for comparing maximum pressures in internal combustion engines. The diaphragm is clamped between two metal washers in a spark plug shell and its thickness is chosen such that, when subjected to explosion pressure, the exposed portion will be sheared from the rim in a short time.

Sparrow, Stanwood W; Lee, Stephen M

1922-01-01

296

Maximum entropy analysis of hydraulic pipe networks  

NASA Astrophysics Data System (ADS)

A Maximum Entropy (MaxEnt) method is developed to infer mean external and internal flow rates and mean pressure gradients (potential differences) in hydraulic pipe networks, without or with sufficient constraints to render the system deterministic. The proposed method substantially extends existing methods for the analysis of flow networks (e.g. Hardy-Cross), applicable only to deterministic networks.

Waldrip, Steven H.; Niven, Robert K.; Abel, Markus; Schlegel, Michael

2014-12-01

297

Network Flow Maximum Flow and Minimum Cut  

E-print Network

3/3/2011 1 1 Chapter 7 Network Flow 2 Maximum Flow and Minimum Cut Max flow and min cut. Two very duality. Nontrivial applications / reductions. Data mining. Open-pit mining. Project selection. Airline-camera scene reconstruction. Many many more ... 3 Flow network. Abstraction for material flowing through

Srinivasan, Padmini

298

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

299

ON THE MAXIMUM MASS OF STELLAR BLACK HOLES  

SciTech Connect

We present the spectrum of compact object masses: neutron stars and black holes (BHs) that originate from single stars in different environments. In particular, we calculate the dependence of maximum BH mass on metallicity and on some specific wind mass loss rates (e.g., Hurley et al. and Vink et al.). Our calculations show that the highest mass BHs observed in the Galaxy M{sub bh} {approx} 15 M{sub sun} in the high metallicity environment (Z = Z{sub sun} = 0.02) can be explained with stellar models and the wind mass loss rates adopted here. To reach this result we had to set luminous blue variable mass loss rates at the level of {approx}10{sup -4} M{sub sun} yr{sup -1} and to employ metallicity-dependent Wolf-Rayet winds. With such winds, calibrated on Galactic BH mass measurements, the maximum BH mass obtained for moderate metallicity (Z = 0.3 Z{sub sun} = 0.006) is M{sub bh,max} = 30 M{sub sun}. This is a rather striking finding as the mass of the most massive known stellar BH is M{sub bh} = 23-34 M{sub sun} and, in fact, it is located in a small star-forming galaxy with moderate metallicity. We find that in the very low (globular cluster-like) metallicity environment the maximum BH mass can be as high as M{sub bh,max} = 80 M{sub sun} (Z = 0.01 Z{sub sun} = 0.0002). It is interesting to note that X-ray luminosity from Eddington-limited accretion onto an 80 M{sub sun} BH is of the order of {approx}10{sup 40} erg s{sup -1} and is comparable to luminosities of some known ultra-luminous X-ray sources. We emphasize that our results were obtained for single stars only and that binary interactions may alter these maximum BH masses (e.g., accretion from a close companion). This is strictly a proof-of-principle study which demonstrates that stellar models can naturally explain even the most massive known stellar BHs.

Belczynski, Krzysztof; Fryer, Chris L. [Los Alamos National Lab, P.O. Box 1663, MS 466, Los Alamos, NM 87545 (United States); Bulik, Tomasz [Astronomical Observatory, University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw (Poland); Ruiter, Ashley [Department of Astronomy, New Mexico State University, 1320 Frenger Mall, Las Cruces, NM 88003 (United States); Valsecchi, Francesca [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Vink, Jorick S. [Armagh Observatory, College Hill, Armagh BT61, 9DG, Northern Ireland (United Kingdom); Hurley, Jarrod R., E-mail: kbelczyn@nmsu.ed, E-mail: tb@astrouw.edu.p, E-mail: clfreyer@lanl.go, E-mail: aruiter@nmsu.ed, E-mail: francesca@u.northwestern.ed, E-mail: jsv@arm.ac.u, E-mail: JHurley@groupwise.swin.edu.a [Centre for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia)

2010-05-10

300

Microdroplet growth mechanism during water condensation on superhydrophobic surfaces.  

PubMed

By promoting dropwise condensation of water, nanostructured superhydrophobic coatings have the potential to dramatically increase the heat transfer rate during this phase change process. As a consequence, these coatings may be a facile method of enhancing the efficiency of power generation and water desalination systems. However, the microdroplet growth mechanism on surfaces which evince superhydrophobic characteristics during condensation is not well understood. In this work, the sub-10 ?m dynamics of droplet formation on nanostructured superhydrophobic surfaces are studied experimentally and theoretically. A quantitative model for droplet growth in the constant base (CB) area mode is developed. The model is validated using optimized environmental scanning electron microscopy (ESEM) imaging of microdroplet growth on a superhydrophobic surface consisting of immobilized alumina nanoparticles modified with a hydrophobic promoter. The optimized ESEM imaging procedure increases the image acquisition rate by a factor of 10-50 as compared to previous research. With the improved imaging temporal resolution, it is demonstrated that nucleating nanodroplets coalesce to create a wetted flat spot with a diameter of a few micrometers from which the microdroplet emerges in purely CB mode. After the droplet reaches a contact angle of 130-150°, its base diameter increases in a discrete steplike fashion. The droplet height does not change appreciably during this steplike base diameter increase, leading to a small decrease of the contact angle. Subsequently, the drop grows in CB mode until it again reaches the maximum contact angle and increases its base diameter in a steplike fashion. This microscopic stick-and-slip motion can occur up to four times prior to the droplet coalescence with neighboring drops. Lastly, the constant contact angle (CCA) and the CB growth models are used to show that modeling formation of a droplet with a 150° contact angle in the CCA mode rather than in the CB mode severely underpredicts both the drop formation time and the average heat transfer rate through the drop. PMID:22548441

Rykaczewski, Konrad

2012-05-22

301

Theoretical Analysis of Maximum Flow Declination Rate versus Maximum Area Declination Rate in Phonation  

ERIC Educational Resources Information Center

Purpose: Maximum flow declination rate (MFDR) in the glottis is known to correlate strongly with vocal intensity in voicing. This declination, or negative slope on the glottal airflow waveform, is in part attributable to the maximum area declination rate (MADR) and in part to the overall inertia of the air column of the vocal tract (lungs to…

Titze, Ingo R.

2006-01-01

302

Flower Power: Sunflowers as a Model for Logistic Growth  

ERIC Educational Resources Information Center

Logistic growth displays an interesting pattern: It starts fast, exhibiting the rapid growth characteristic of exponential models. As time passes, it slows in response to constraints such as limited resources or reallocation of energy. The growth continues to slow until it reaches a limit, called capacity. When the growth describes a population,…

Fernandez, Eileen; Geist, Kristi A.

2011-01-01

303

Early coding of reaching in the parietooccipital cortex.  

PubMed

Neural activity was recorded in the parietooccipital cortex while monkeys performed different tasks aimed at investigating visuomotor interactions of retinal, eye, and arm-related signals on neural activity. The tasks were arm reaching 1) to foveated targets; 2) to extrafoveal targets, with constant eye position; 3) within an instructed-delayed paradigm, under both light and darkness; 4) saccadic eye movements toward, and static eye holding on peripheral targets; and 5) visual fixation and stimulation. The activity of many cells was modulated during arm reaction (68%) and movement time (58%), and during static holding of the arm in space (64%), when eye position was kept constant. Eye position influenced the activity of many cells during hand reaction (45%) and movement time (51%) and holding of hand static position (69%). Many cells (56%) were also modulated during preparation for hand movement, in the delayed reach task. Modulation was present also in the dark in 59% of cells during this epoch, 51% during reaction and movement time, and 48% during eye/hand holding on the target. Cells (50%) displaying light-dark differences of activity were considered as related to the sight and monitoring of hand motion and/or position in the visual field. Saccadic eye movements modulated a smaller percentage (25%) of cells than eye position (68%). Visual receptive fields were mapped in 44% of the cells studied. They were generally large and extended to the periphery of the tested (30 degrees ) visual field. Sixty-six percent of cells were motion sensitive. Therefore the activity of many neurons in this area reflects the combined influence of visual, eye, and arm movement-related signals. For most neurons, the orientation of the preferred directions computed across different epochs and tasks, therefore expression of all different eye- and hand-related activity types, clustered within a limited sector of space, the field of global tuning. These spatial fields might be an ideal frame to combine eye and hand signals, thanks to the congruence of their tuning properties. The relationships between cell activity and oculomotor and visuomanual behavior were task dependent. During saccades, most cells were recruited when the eye moved to a spatial location that was also target for hand movement, whereas during hand movement most cells fired depending on whether or not the animal had prior knowledge about the location of the visual targets. PMID:10758140

Battaglia-Mayer, A; Ferraina, S; Mitsuda, T; Marconi, B; Genovesio, A; Onorati, P; Lacquaniti, F; Caminiti, R

2000-04-01

304

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

305

Reaching out to the Community: A DPS Speakers' Bureau  

NASA Astrophysics Data System (ADS)

One of the most frequent ways in which scientists reach out to the community is through public presentations, which are often informal and held at local schools, planetariums, and museums. These talks are usually arranged by personal contact between the scientist and a person at the host institution. We propose to facilitate these contacts by creating a voluntary DPS Speakers' Bureau. Respondents to the 2000 Education/Public Outreach Survey conducted by E. Miner expressed interest in this idea: 40% of respondents indicated a willingness to participate. The benefits of the Bureau would be many: it could serve regional needs for planetariums, museums, and clubs, as well as some limited formal education needs in local schools. The Bureau could also be useful to the media trying to locate experts on particular topics. We propose to implement a one-year trial run for the Bureau. We propose to make this service available via the DPS web site. Method of coordination is yet to be determined and input from potential participants is solicited. We will consider linking the Speakers' Bureau web page to the web sites run by the National Science Teachers' Association, the International Planetarium Society, and the Solar System Exploration E/PO site at NASA. A sign-up sheet for additional potential participants will be available at the poster site.

Lopes, R. M. C.; Lebofsky, L.; Miner, E.; Lowes, L.

2001-11-01

306

Breakthrough Capability for UVOIR Space Astronomy: Reaching the Darkest Sky  

NASA Technical Reports Server (NTRS)

We describe how availability of new solar electric propulsion (SEP) technology can substantially increase the science capability of space astronomy missions working within the near-UV to far-infrared (UVOIR) spectrum by making dark sky orbits accessible for the first time. We present two case studies in which SEP is used to enable a 700 kg Explorer-class and 7000 kg flagship-class observatory payload to reach an orbit beyond where the zodiacal dust limits observatory sensitivity. The resulting scientific performance advantage relative to a Sun-Earth L2 point (SEL2) orbit is presented and discussed. We find that making SEP available to astrophysics Explorers can enable this small payload program to rival the science performance of much larger long development-time systems. Similarly, we find that astrophysics utilization of high power SEP being developed for the Asteroid Redirect Robotics Mission (ARRM) can have a substantial impact on the sensitivity performance of heavier flagship-class astrophysics payloads such as the UVOIR successor to the James Webb Space Telescope.

Greenhouse, Matthew A.; Benson, Scott W.; Englander, Jacob; Falck, Robert D.; Fixsen, Dale J.; Gardner, Jonathan P.; Kruk, Jeffery W.; Oleson, Steven R.; Thronson, Harley A.

2015-01-01

307

Learning to Reach to Locations Encoded from Imaging Displays  

PubMed Central

The present study investigated how people learn to correct errors in actions directed toward cognitively encoded spatial locations. Subjects inserted a stylus to reach a hidden target localized by means of ultrasound imaging and portrayed with a scaled graph. As was found previously (Wu et al., 2005), subjects initially underestimated the target location but corrected their responses when given training with feedback. Three experiments were conducted to examine whether the error correction occurred at (1) the mapping from the input to a mental representation of target location; (2) the mapping from the representation of target location to the intended insertion response, or (3) the mapping from intended response to action. Experiment 1 and Experiment 3 disconfirmed Mappings 1 and 3, respectively, by showing that training did not alter independent measures of target localization or the action of aiming. Experiment 2 showed that the output of Mapping 2, the planned response -- measured as the initial insertion angle –was corrected over trials, and the correction magnitude predicted the response to a transfer stimulus with a new represented location. PMID:19177177

Wu, Bing; Klatzky, Roberta L.; Stetten, George

2008-01-01

308

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

309

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

310

Entirely passive reach extended GPON using Raman amplification.  

PubMed

In previous investigation of extended GPON system, we employed 1240 nm and 1427 nm dual pumps within optical line terminal (OLT) equipments at central office (CO) to provide distributed Raman gains of upstream 1310 nm and downstream 1490 nm signals. These pump wavelengths were selected to ensure compatibility with the standard GPON wavelengths and reduce the unwanted pump-to-signal interactions. In this paper, we propose a new system scheme for an entirely-passive extended reach GPON to further enhance the system performance by eliminating the pump-to-signal interactions. In this scheme, a 1240 nm laser is employed to provide counter-pumping distributed Raman amplification of the upstream 1310 nm signal, and a discrete Raman amplifier is integrated with the 1490 nm transmitter to booster the downstream signal power and to improve the link loss budget. An operation over 60-km of zero-water-peak Allwave® fiber with a 1:128 way splitter is experimentally demonstrated at 2.5 Gbit/s. The system performance of such purely passive GPON extender is investigated in the paper. The system transmission limitation of upstream signal due to Raman ASE noises is discussed, and the non-linear impairment on downstream signal due to high launch power into feeder fiber is also examined. PMID:21164685

Zhu, Benyuan

2010-10-25

311

Breakthrough capability for UVOIR space astronomy: Reaching the darkest sky  

NASA Astrophysics Data System (ADS)

We describe how availability of new solar electric propulsion (SEP) technology can substantially increase the science capability of space astronomy missions working within the near-UV to far-infrared (UVOIR) spectrum by making dark sky orbits accessible for the first time. We present a proof of concept case study in which SEP is used to enable a 700 kg Explorer-class observatory payload to reach an orbit beyond where the zodiacal dust limits observatory sensitivity. The resulting scientific performance advantage relative to a Sun-Earth L2 point orbit is presented and discussed. We find that making SEP available to astrophysics Explorers can enable this small payload program to rival the science performance of much larger long development-time systems. We also present flight dynamics analysis which illustrates that this concept can be extended beyond Explorers to substantially improve the sensitivity performance of heavier (7000 kg) flagship-class astrophysics payloads such as the UVOIR successor to the James Webb Space Telescope by using high power SEP that is being developed for the Asteroid Redirect Robotics Mission.

Greenhouse, Matthew A.; Benson, Scott W.; Englander, Jacob; Falck, Robert D.; Fixsen, Dale J.; Gardner, Jonathan P.; Kruk, Jeffrey W.; Oleson, Steven R.; Thronson, Harley A.

2015-02-01

312

How posture affects macaques' reach-to-grasp movements.  

PubMed

Although there is a wealth of behavioral data regarding grasping movements in non-human primates, how posture influences the kinematics of prehensile behavior is not yet clearly understood. The purpose of this study was to examine and compare kinematic descriptions of grip behaviors while primates (macaque monkeys) were in a sitting posture or when stopping after quadrupedal locomotion (i.e., tripedal stance). Video footage taken while macaques grasped objects was analyzed frame-by-frame using digitalization techniques. Each of the two grip types considered (power and precision grips) was found to be characterized by specific, distinct kinematic signatures for both the reaching and the grasping components when those actions were performed in a sitting position. The grasping component did not differentiate in relation to the type of grip that was needed when, instead, the prehensile action took place in a tripedal stance. Quadrupedal locomotion affected the concomitant organization of prehensile activities determining in fact a similar kinematic patterning for the two grips regardless of the size of the object to be grasped. It is suggested that using a single kinematic grip patterning for all prehensile activities might be both the by-product of planning a grasping action while walking and a way to simplify motor programming during unstable tripedal stance. PMID:24337352

Sartori, Luisa; Camperio-Ciani, Andrea; Bulgheroni, Maria; Castiello, Umberto

2014-03-01

313

Impulsivity Modulates Performance Under Response Uncertainty in a Reaching Task  

PubMed Central

We sought to explore the interaction of the impulsivity trait with response uncertainty. To this end, we used a reaching task (Pellizzer and Hedges 2003) where a motor response direction was cued at different levels of uncertainty (1 cue, ie no uncertainty, 2 cues or 3 cues). Data from 95 healthy adults (54 F, 41 M) were analyzed. Impulsivity was measured using the Barratt Impulsiveness Scale version 11 (BIS-11). Psychophysical variables recorded were reaction time (RT), errors of commission (referred to as “early errors”) and errors of precision. Data analysis employed generalised linear mixed models and generalized additive mixed models. Results For the early errors there was an interaction of impulsivity with uncertainty and gender, with increased errors for high impulsivity in the one-cue condition for women and the three cue condition for men. There was no effect of impulsivity on precision errors or RT. However, the analysis of the effect of RT and impulsivity on precision errors showed a different pattern for high vs low impulsives in the high uncertainty (3-cue) condition. In addition, there was a significant early error speed-accuracy tradeoff for women, primarily in low uncertainty and a “reverse” speed accuracy tradeoff for men in high uncertainty. We believe that these results extend the results of past studies of impulsivity which help define it as a behavioural trait that modulates speed vs accuracy response styles depending on environmental constraints and highlight once more the importance of gender in the interplay of personality and behaviour. PMID:23239199

Tzagarakis, C; Pellizzer, G; Rogers, RD

2013-01-01

314

Hypothesis: origin of life in deep-reaching tectonic faults.  

PubMed

The worldwide discussion on the origin of life encounters difficulties when it comes to estimate the conditions of the early earth and to define plausible environments for the development of the first complex organic molecules. Until now, the role of the earth's crust has been more or less ignored. In our opinion, deep-reaching open, interconnected tectonic fault systems may provide possible reaction habitats ranging from nano- to centimetre and even larger dimensions for the formation of prebiotic molecules. In addition to the presence of all necessary raw materials including phosphate, as well as variable pressure and temperature conditions, we suggest that supercritical CO2 as a nonpolar solvent could have played an important role. A hypothetical model for the origin of life is proposed which will be used to design crucial experiments for the model's verification. Because all proposed processes could still occur in tectonic faults at the present time, it may be possible to detect and analyse the formation of prebiotic molecules in order to assess the validity of the proposed hypothesis. PMID:22373604

Schreiber, Ulrich; Locker-Grütjen, Oliver; Mayer, Christian

2012-02-01

315

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. 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

2014-01-01

316

Recycling in 1998: States moving forward to reach higher goals  

SciTech Connect

As the end of the decade--and century--approaches, the US still is working to push the recycling envelope. The US as a whole has reached its higher recycling rate ever--27%, according to the US EPA, and individual states are striving to meet and surpass their own recycling goals. Yet, it is difficult to compare rates and goals and budgets of individual states to one another, and come up with the nationwide trend in terms of recycling. Comparing recycling programs from state to state is like comparing apples and oranges. Individual states recycle a different amount of material, include a range of materials in their recycling-rate calculations, and have a variety of costs associated with performing these activities. Recycling in New York City is nothing like recycling in Boise, Idaho, for instance. This article presents information from all 50 states and the District of Columbia on their recycling rates, goals, waste generation rates, and the resources they have allocated toward recycling efforts.

Heumann, J.M.; Egan, K.

1998-08-01

317

Reach Scale Hydraulic Assessment of Instream Salmonid Habitat Restoration  

NASA Astrophysics Data System (ADS)

This study investigates the use of a two-dimensional hydrodynamic model (River2D) for an assessment of the effects of instream large woody debris and rock groyne habitat structures. The bathymetry of a study reach (a side channel of the Chilliwack River located in southwestern British Columbia) was surveyed after the installation of 11 instream restoration structures. A digital elevation model was developed and used with a hydrodynamic model to predict local velocity, depth, scour, and habitat characteristics. The channel was resurveyed after the fall high-flow season during which a bankfull event occurred. Pre-flood and post-flood bathymetry pool distributions were compared. Measured scour was compared to predicted shear and pre-flood and post-flood fish habitat indices for coho salmon (Oncorhynchus kisutch) and steelhead trout (O. mykiss) were compared. Two-dimensional flow model velocity and depth predictions compare favorably to measured field values with mean standard errors of 24 percent and 6 percent, respectively, while areas of predicted high shear coincide with the newly formed pool locations. At high flows, the fish habitat index used (weighted usable area) increased by 150 percent to 210 percent. The application of the hydrodynamic model indicated a net habitat benefit from the restoration activities and provides a means of assessing and optimizing planned works.

Lacey, R. W. Jay; Millar, Robert G.

2004-12-01

318

Parametric design studies of long-reach manipulators  

SciTech Connect

A number of different approaches have been studied for remediation of waste storage tanks at various sites. One of the most promising approaches is the use of a high-capacity, long-reach manipulation (LRM) system with a variety of end effectors for dislodging the waste. LRMs may have characteristics significantly different from those of industrial robots due to the long links needed to cover the large workspace. Because link lengths are much greater than their diameters, link flexibility, as well as joint or drive train flexibility, is likely to be significant. LRMs will be required for a variety of applications in the Environmental Restoration and Waste Management Program. While each application will present specific functional, kinematic, and performance requirements, a design approach for determining the kinematic applicability and performance characteristics considering link flexibility is presented with a focus on waste storage tank remediation. This paper addresses key design issues for LRM-based waste retrieval systems. It discusses the effects of parameters such as payload capacity, storage tanks size, and access port diameter on manipulator structural design. The estimated weight, fundamental natural frequency, and static deflection of the manipulator have been calculated for various parameter conditions.

Kwon, D.S.; March-Leuba, S.; Babcock, S.M.; Burks, B.L.; Hamel, W.R.

1993-11-01

319

Pareto versus lognormal: A maximum entropy test  

NASA Astrophysics Data System (ADS)

It is commonly found that distributions that seem to be lognormal over a broad range change to a power-law (Pareto) distribution for the last few percentiles. The distributions of many physical, natural, and social events (earthquake size, species abundance, income and wealth, as well as file, city, and firm sizes) display this structure. We present a test for the occurrence of power-law tails in statistical distributions based on maximum entropy. This methodology allows one to identify the true data-generating processes even in the case when it is neither lognormal nor Pareto. The maximum entropy approach is then compared with other widely used methods and applied to different levels of aggregation of complex systems. Our results provide support for the theory that distributions with lognormal body and Pareto tail can be generated as mixtures of lognormally distributed units.

Bee, Marco; Riccaboni, Massimo; Schiavo, Stefano

2011-08-01

320

On optimizing maximum-power heat engines  

NASA Astrophysics Data System (ADS)

For a general class of heat engines operating at maximum power, in which the generic sources of irreversibility are finite-rate heat transfer and friction only, a study is made of (1) the time-dependent driving functions that maximize power when heat input and heat rejection are constrained to be nonisothermal, as is the case in many conventional heat engines, and (2) the specific impact of friction on the nature of the engine cycle that maximizes power, and on the engine's power-efficiency characteristics. The extent to which maximum power is affected by the constraints on the driving function is evaluated, as well as the time divisions on the different branches of the optimal cycle. The fundamental differences in engine performance that arise from frictional losses being internally dissipative, as opposed to externally dissipative, are derived, and illustrative examples are presented.

Gordon, J. M.; Huleihil, Mahmoud

1991-01-01

321

MAXIMUM LIKELIHOOD ESTIMATION FOR SOCIAL NETWORK DYNAMICS  

PubMed Central

A model for network panel data is discussed, based on the assumption that the observed data are discrete observations of a continuous-time Markov process on the space of all directed graphs on a given node set, in which changes in tie variables are independent conditional on the current graph. The model for tie changes is parametric and designed for applications to social network analysis, where the network dynamics can be interpreted as being generated by choices made by the social actors represented by the nodes of the graph. An algorithm for calculating the Maximum Likelihood estimator is presented, based on data augmentation and stochastic approximation. An application to an evolving friendship network is given and a small simulation study is presented which suggests that for small data sets the Maximum Likelihood estimator is more efficient than the earlier proposed Method of Moments estimator. PMID:25419259

Snijders, Tom A.B.; Koskinen, Johan; Schweinberger, Michael

2014-01-01

322

Zipf's law, power laws and maximum entropy  

NASA Astrophysics Data System (ADS)

Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines—from astronomy to demographics to software structure to economics to linguistics to zoology, and even warfare. A recent model of random group formation (RGF) attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present paper I argue that the specific cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified.

Visser, Matt

2013-04-01

323

Reconstruction of the 1707 Hoei, Japan, tsunami that reached the southern coast of the Korean Peninsula  

NASA Astrophysics Data System (ADS)

The 11 March 2011 Tohoku, Japan, tsunami reached the coast of Jeju Island, the southernmost Korean Peninsula, after about five hours from the origin time of the earthquake. The island is located in the backside of the epicentral Pacific region, and the direct propagation path is blocked by the Japanese Islands Arc. It implies that the tsunami observed in the Jeju Island is diffracted waves. The wave height observed in the island reaches about 0.2 m. There is no report of damage caused by the tsunami. On the other hand, there is a historical document which records an observation of earthquake and tidal waves simultaneously in the island. The date corresponds to the occurrence of the great 1707 Hoei earthquake (M~9) and tsunami in the Nankai and Tonankai areas, the offshore southern Honshu, Japan. The propagation path to the island of the Hoei tsunami is similar to that of the Tohoku tsunami, but is much shorter than it. In this study, we try to show that the 1707 historical observations in the Jeju Island was resulted from the great Hoei earthquake and tsunami in Japan, and how the maximum wave height was. Numerical simulations and investigations of historical documents are performed in parallel for this purpose. We assume that the source information of the 2011 Tohoku earthquake would be comparable to the 1707 Hoei earthquake because of the similar magnitude and tectonic environment. Therefore numerical simulations employ a variety of fault rupture models which are determined for the 2011 Tohoku earthquake. This study may extend to the prediction of any future tsunami in the island due to the potential megathrust earthquake which is expected to be co-located with the 1707 Hoei earthquake.

Kim, S.; Kang, T.

2012-12-01

324

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

325

Maximum likelihood estimation of population parameters  

Microsoft Academic Search

One of the most important parameters in population genetics is [theta] = 4N[sub e][mu] where N[sub e] is the effective population size and [mu] is the rate of mutation per gene per generation. The authors study two related problems, using the maximum likelihood method and the theory of coalescence. One problem is the potential improvement of accuracy in estimating the

Y. X. Fu; W. H. Li

1993-01-01

326

The Maximum Size of Dynamic Data Structures  

E-print Network

_->l. MAXIMUM SIZE OF DYNAMIC DATA STRUCTURES 811 intervals [ti, ti+l], with endpoints ti=i/n, for O Size2 _- a2 (2.3) dynamic queries over time. Let us denote the data structure size at time by Size(t). If we think of the items as horizontal intervals, then Size(t) is just the number of intervals "cut" by the vertical line...

Kenyon-Mathieu, Claire M.; Vitter, Jeffrey Scott

1991-10-01

327

The Maximum Principle for Holomorphic Operator Functions  

Microsoft Academic Search

We show that if an operator-valued analytic function f of a complex variable attains its maximum modulus at z\\u000a 0, then the coefficients of the nonconstant terms in the power series expansion about z\\u000a 0 cannot be invertible, provided a complex uniform convexity condition holds. One application is that the norm of the resolvent\\u000a of an operator on a complex

Andrzej Daniluk

2011-01-01

328

Dialogue act recognition using maximum entropy  

Microsoft Academic Search

A dialogue-based interface for information systems is considered a potentially very useful approach to infor- mation access. A key step in computer processing of natural-language dialogues is dialogue-act (DA) recogni- tion. In this paper, we apply a feature-based classification approach for DA recognition, by using the maximum entropy (ME) method to build a classifier for labeling utterances with DA tags.

Kwok Cheung Lan; Kei Shiu Ho; Robert Wing Pong Luk; Hong Va Leong

2008-01-01

329

Therapeutic Experience of Maximum Feasible Participation  

E-print Network

Therapeutic Experience of Maximum Feasible Participation George Pierre Castile In 1965 a number of scholars looked about them at the state of Native Americans, among them was Henry Dobyns, whose contribution to the collec tion, "The American... Indian Today," was titled "Therapeutic Experience of Re sponsible Democracy" (Dobyns 1968). This phrase was taken from a statement by John Collier, Commissioner of Indian affairs from 1933-45. Collier had de clared "The experience of responsible...

Castile, George Pierre

2006-03-01

330

Reach-scale channel sensitivity to multiple human activities and natural events: Lower Santa Clara River, California, USA  

NASA Astrophysics Data System (ADS)

Understanding the cumulative impact of natural and human influences on the sensitivity of channel morphodynamics, a relative measure between the drivers for change and the magnitude of channel response, requires an approach that accommodates spatial and temporal variability in the suite of primary stressors. Multiple historical data sources were assembled to provide a reach-scale analysis of the lower Santa Clara River (LSCR) in Ventura County, California, USA. Sediment supply is naturally high due to tectonic activity, earthquake-generated landslides, wildfires, and high magnitude flow events during El Niño years. Somewhat typically for the region, the catchment has been subject to four reasonably distinct land use and resource management combinations since European-American settlement. When combined with analysis of channel morphological response (quantifiable since ca. 1930), reach-scale and temporal differences in channel sensitivity become apparent. Downstream reaches have incised on average 2.4 m and become narrower by almost 50% with changes focused in a period of highly sensitive response after about 1950 followed by forced insensitivity caused by structural flood embankments and a significant grade control structure. In contrast, the middle reaches have been responsive but are morphologically resilient, and the upstream reaches show a mildly sensitive aggradational trend. Superimposing the natural and human drivers for change reveals that large scale stressors (related to ranching and irrigation) have been replaced over time by a suite of stressors operating at multiple spatial scales. Lower reaches have been sensitive primarily to 'local' scale impacts (urban growth, flood control, and aggregate mining) whereas, upstream, catchment-scale influences still prevail (including flow regulation and climate-driven sediment supply factors). These factors illustrate the complexity inherent to cumulative impact assessment in fluvial systems, provide evidence for a distinct Anthropocene fluvial response, and underpin the enormity of the challenge faced in trying to sustainably manage and restore rivers.

Downs, Peter W.; Dusterhoff, Scott R.; Sears, William A.

2013-05-01

331

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

332

"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

333

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

334

Continuity of the Maximum-Entropy Inference  

NASA Astrophysics Data System (ADS)

We study the inverse problem of inferring the state of a finite-level quantum system from expected values of a fixed set of observables, by maximizing a continuous ranking function. We have proved earlier that the maximum-entropy inference can be a discontinuous map from the convex set of expected values to the convex set of states because the image contains states of reduced support, while this map restricts to a smooth parametrization of a Gibbsian family of fully supported states. Here we prove for arbitrary ranking functions that the inference is continuous up to boundary points. This follows from a continuity condition in terms of the openness of the restricted linear map from states to their expected values. The openness condition shows also that ranking functions with a discontinuous inference are typical. Moreover it shows that the inference is continuous in the restriction to any polytope which implies that a discontinuity belongs to the quantum domain of non-commutative observables and that a geodesic closure of a Gibbsian family equals the set of maximum-entropy states. We discuss eight descriptions of the set of maximum-entropy states with proofs of accuracy and an analysis of deviations.

Stephan, Weis

2014-09-01

335

Continuity of the Maximum-Entropy Inference  

E-print Network

We study the inverse problem of inferring the state of a finite-level quantum system from expected values of a fixed set of observables, by maximizing a continuous ranking function. We have proved earlier that the maximum-entropy inference can be a discontinuous map from the convex set of expected values to the convex set of states because the image contains states of reduced support, while this map restricts to a smooth parametrization of a Gibbsian family of fully supported states. Here we prove for arbitrary ranking functions that the inference is continuous up to boundary points. This follows from a continuity condition in terms of the openness of the restricted linear map from states to their expected values. The openness condition shows also that ranking functions with a discontinuous inference are typical. Moreover it shows that the inference is continuous in the restriction to any polytope which implies that a discontinuity belongs to the quantum domain of non-commutative observables and that a geodesic closure of a Gibbsian family equals the set of maximum-entropy states. We discuss eight descriptions of the set of maximum-entropy states with proofs of accuracy and an analysis of deviations.

Stephan Weis

2014-04-21

336

Vegetation controls on the maximum size of coastal dunes  

PubMed Central

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.

2013-01-01

337

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

338

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

339

Subsurface chlorophyll maximum layers: enduring enigma or mystery solved?  

PubMed

The phenomenon of subsurface chlorophyll maximum layers (SCMLs) is not a unique ecological response to environmental conditions; rather, a broad range of interacting processes can contribute to the formation of persistent layers of elevated chlorophyll a concentration (Chl) that are nearly ubiquitous in stratified surface waters. Mechanisms that contribute to the formation and maintenance of the SCMLs include a local maximum in phytoplankton growth rate near the nutricline, photoacclimation of pigment content that leads to elevated Chl relative to phytoplankton biomass at depth, and a range of physiologically influenced swimming behaviors in motile phytoplankton and buoyancy control in diatoms and cyanobacteria that can lead to aggregations of phytoplankton in layers, subject to grazing and physical control. A postulated typical stable water structure characterizes consistent patterns in vertical profiles of Chl, phytoplankton biomass, nutrients, and light across a trophic gradient structured by the vertical flux of nutrients and characterized by the average daily irradiance at the nutricline. Hypothetical predictions can be tested using a nascent biogeochemical global ocean observing system. Partial results to date are generally consistent with predictions based on current knowledge, which has strong roots in research from the twentieth century. PMID:25251268

Cullen, John J

2015-01-01

340

Eyelid Growths  

MedlinePLUS

... Eye Disorders > Eyelid and Tearing Disorders 4 Eyelid Growths Noncancerous (benign) and cancerous (malignant) growths can form ... a microscope (biopsied) to exclude cancer. Other cancerous growths of the eyelids: Although less common, squamous cell ...

341

Growth Disorders  

MedlinePLUS

... because their parents are. But some children have growth disorders. Growth disorders are problems that prevent children from developing ... or other features. Very slow or very fast growth can sometimes signal a gland problem or disease. ...

342

Bimanual Reaching across the Hemispace: Which Hand Is Yoked to Which?  

ERIC Educational Resources Information Center

When both hands perform concurrent goal-directed reaches, they become yoked to one another. To investigate the direction of this coupling (i.e., which hand is yoked to which), the temporal dynamics of bimanual reaches were compared with equivalent-amplitude unimanual reaches. These reaches were to target pairs located on either the left or right…

Buckingham, Gavin; Binsted, Gordon; Carey, David P.

2010-01-01

343

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

344

Forest evaporation models: relationships between stand growth and evaporation  

NASA Astrophysics Data System (ADS)

The relationships between forest stand structure, growth and evaporation were analysed to determine whether forest evaporation can be estimated from stand growth data. This approach permits rapid assessment of the potential impacts of afforestation on the water regime. The basis for this approach is (a) that growth rates are determined by water availability and limited by the maximum water extraction potential, and (b) that stand evaporation is proportional to biomass and biomass increment. The relationships between stand growth and evaporation were modelled for a set of catchment experiments where estimates of both growth and evaporation were available. The predicted mean evaporation, over periods of several years, was generally within 10% of the measured mean annual evaporation (rainfall minus streamflow) when the model from one catchment was applied to other catchments planted with the same species. The residual evaporation, after fitting the models, was correlated with rainfall: above-average rainfall resulted in above-average evaporation. This relationship could be used to derive estimates for dry and wet years. Analyses using the models provide additional evidence that Eucalyptus grandis may be depleting groundwater reserves in catchments where its roots can reach the water table. The models are designed to be integrated into a plantation management system which uses a geographic information system for spatial analysis and modelling. The use of readily available growth parameters as predictor variables may reduce our dependence on intricate process-based models. This is seen as an efficient way of extrapolating existing catchment data — reflecting the impacts of forestry on water supplies across a range of sites, climatic zones and species. This approach has the potential for further development, especially in dealing with low flows and faster growing species.

Le Maitre, D. C.; Versfeld, D. B.

1997-06-01

345

Work Element B: 157. Sampling in Fish-Bearing Reaches [Variation in Productivity in Headwater Reaches of the Wenatchee Subbasin], Final Report for PNW Research Station.  

SciTech Connect

We studied variation in productivity in headwater reaches of the Wenatchee subbasin for multiple field seasons with the objective that we could develop methods for monitoring headwater stream conditions at the subcatchment and stream levels, assign a landscape-scale context via the effects of geoclimatic parameters on biological productivity (macroinvertebrates and fish) and use this information to identify how variability in productivity measured in fishless headwaters is transmitted to fish communities in downstream habitats. In 2008, we addressed this final objective. In collaboration with the University of Alaska Fairbanks we found some broad differences in the production of aquatic macroinvertebrates and in fish abundance across categories that combine the effects of climate and management intensity within the subbasin (ecoregions). From a monitoring standpoint, production of benthic macroinvertebrates was not a good predictor of drifting macroinvertebrates and therefore might be a poor predictor of food resources available to fish. Indeed, there is occasionally a correlation between drifting macroinvertebrate abundance and fish abundance which suggests that headwater-derived resources are important. However, fish in the headwaters appeared to be strongly food-limited and there was no evidence that fishless headwaters provided a consistent subsidy to fish in reaches downstream. Fish abundance and population dynamics in first order headwaters may be linked with similar metrics further down the watershed. The relative strength of local dynamics and inputs into productivity may be constrained or augmented by large-scale biogeoclimatic control. Headwater streams are nested within watersheds, which are in turn nested within ecological subregions; thus, we hypothesized that local effects would not necessarily be mutually exclusive from large-scale influence. To test this we examined the density of primarily salmonid fishes at several spatial and temporal scales within a major sub-basin of the Columbia River and associations of density with ecoregion and individuals drainages within the sub-basin. We further examined habitat metrics that show positive associations with fish abundance to see if these relationships varied at larger spatial scales. We examined the extent to which headwater fish density and temporal variation in density were correlated between the headwaters and the main tributaries of the sub-basin, and the influence of ecoregion influence on density differences, particularly at wider temporal scales. Finally, we examined demographic parameters such as growth and emigration to determine whether density-dependence differs among ecoregions or whether responses were more strongly influenced by the demography of the local fish population.

Polivka, Karl; Bennett, Rita L. [USDA Forest Service, Pacific Northwest Research Station, Wenatchee, WA

2009-03-31

346

Robots Explore the Farthest Reaches of Earth and Space  

NASA Technical Reports Server (NTRS)

"We were the first that ever burst/Into that silent sea," the title character recounts in Samuel Taylor Coleridge s opus Rime of the Ancient Mariner. This famous couplet is equally applicable to undersea exploration today as surface voyages then, and has recently been applied to space travel in the title of a chronicle of the early years of human space flight ("Into That Silent Sea: Trailblazers of the Space Era, 1961-1965"), companion to the +n the Shadow of the Moon book and movie. The parallel is certainly fitting, considering both fields explore unknown, harsh, and tantalizingly inhospitable environments. For starters, exploring the Briny Deep and the Final Frontier requires special vehicles, and the most economical and safest means for each employ remotely operated vehicles (ROVs). ROVs have proven the tool of choice for exploring remote locations, allowing scientists to explore the deepest part of the sea and the furthest reaches of the solar system with the least weight penalty, the most flexibility and specialization of design, and without the need to provide for sustaining human life, or the risk of jeopardizing that life. Most NASA probes, including the historic Voyager I and II spacecraft and especially the Mars rovers, Spirit and Opportunity, feature remote operation, but new missions and new planetary environments will demand new capabilities from the robotic explorers of the future. NASA has an acute interest in the development of specialized ROVs, as new lessons learned on Earth can be applied to new environments and increasingly complex missions in the future of space exploration.

2008-01-01

347

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

348

Axon Stretch Growth: The Mechanotransduction of Neuronal Growth  

PubMed Central

During pre-synaptic embryonic development, neuronal processes traverse short distances to reach their targets via growth cone. Over time, neuronal somata are separated from their axon terminals due to skeletal growth of the enlarging organism (Weiss 1941; Gray, Hukkanen et al. 1992). This mechanotransduction induces a secondary mode of neuronal growth capable of accommodating continual elongation of the axon (Bray 1984; Heidemann and Buxbaum 1994; Heidemann, Lamoureux et al. 1995; Pfister, Iwata et al. 2004). Axon Stretch Growth (ASG) is conceivably a central factor in the maturation of short embryonic processes into the long nerves and white matter tracts characteristic of the adult nervous system. To study ASG in vitro, we engineered bioreactors to apply tension to the short axonal processes of neuronal cultures (Loverde, Ozoka et al. 2011). Here, we detail the methods we use to prepare bioreactors and conduct ASG. First, within each stretching lane of the bioreactor, neurons are plated upon a micro-manipulated towing substrate. Next, neurons regenerate their axonal processes, via growth cone extension, onto a stationary substrate. Finally, stretch growth is performed by towing the plated cell bodies away from the axon terminals adhered to the stationary substrate; recapitulating skeletal growth after growth cone extension. Previous work has shown that ASG of embryonic rat dorsal root ganglia neurons are capable of unprecedented growth rates up to 10mm/day, reaching lengths of up to 10cm; while concurrently resulting in increased axonal diameters (Smith, Wolf et al. 2001; Pfister, Iwata et al. 2004; Pfister, Bonislawski et al. 2006; Pfister, Iwata et al. 2006; Smith 2009). This is in dramatic contrast to regenerative growth cone extension (in absence of mechanical stimuli) where growth rates average 1mm/day with successful regeneration limited to lengths of less than 3cm (Fu and Gordon 1997; Pfister, Gordon et al. 2011). Accordingly, further study of ASG may help to reveal dysregulated growth mechanisms that limit regeneration in the absence of mechanical stimuli. PMID:21860373

Loverde, Joseph R.; Tolentino, Rosa E.; Pfister, Bryan J.

2011-01-01

349

Axon stretch growth: the mechanotransduction of neuronal growth.  

PubMed

During pre-synaptic embryonic development, neuronal processes traverse short distances to reach their targets via growth cone. Over time, neuronal somata are separated from their axon terminals due to skeletal growth of the enlarging organism (Weiss 1941; Gray, Hukkanen et al. 1992). This mechanotransduction induces a secondary mode of neuronal growth capable of accommodating continual elongation of the axon (Bray 1984; Heidemann and Buxbaum 1994; Heidemann, Lamoureux et al. 1995; Pfister, Iwata et al. 2004). Axon Stretch Growth (ASG) is conceivably a central factor in the maturation of short embryonic processes into the long nerves and white matter tracts characteristic of the adult nervous system. To study ASG in vitro, we engineered bioreactors to apply tension to the short axonal processes of neuronal cultures (Loverde, Ozoka et al. 2011). Here, we detail the methods we use to prepare bioreactors and conduct ASG. First, within each stretching lane of the bioreactor, neurons are plated upon a micro-manipulated towing substrate. Next, neurons regenerate their axonal processes, via growth cone extension, onto a stationary substrate. Finally, stretch growth is performed by towing the plated cell bodies away from the axon terminals adhered to the stationary substrate; recapitulating skeletal growth after growth cone extension. Previous work has shown that ASG of embryonic rat dorsal root ganglia neurons are capable of unprecedented growth rates up to 10mm/day, reaching lengths of up to 10 cm; while concurrently resulting in increased axonal diameters (Smith, Wolf et al. 2001; Pfister, Iwata et al. 2004; Pfister, Bonislawski et al. 2006; Pfister, Iwata et al. 2006; Smith 2009). This is in dramatic contrast to regenerative growth cone extension (in absence of mechanical stimuli) where growth rates average 1mm/day with successful regeneration limited to lengths of less than 3 cm (Fu and Gordon 1997; Pfister, Gordon et al. 2011). Accordingly, further study of ASG may help to reveal dysregulated growth mechanisms that limit regeneration in the absence of mechanical stimuli. PMID:21860373

Loverde, Joseph R; Tolentino, Rosa E; Pfister, Bryan J

2011-01-01

350

30 CFR 57.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Maximum acceleration and deceleration. 57.19062 Section...Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2012-07-01

351

30 CFR 57.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Maximum acceleration and deceleration. 57.19062 Section...Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2011-07-01

352

30 CFR 56.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Maximum acceleration and deceleration. 56.19062 Section...Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2012-07-01

353

30 CFR 57.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Maximum acceleration and deceleration. 57.19062 Section...Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2013-07-01

354

30 CFR 57.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Maximum acceleration and deceleration. 57.19062 Section...Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2014-07-01

355

30 CFR 56.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Maximum acceleration and deceleration. 56.19062 Section...Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2013-07-01

356

30 CFR 56.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Maximum acceleration and deceleration. 56.19062 Section...Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2011-07-01

357

30 CFR 56.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Maximum acceleration and deceleration. 56.19062 Section...Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2010-07-01

358

30 CFR 57.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Maximum acceleration and deceleration. 57.19062 Section...Procedures § 57.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2010-07-01

359

30 CFR 56.19062 - Maximum acceleration and deceleration.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Maximum acceleration and deceleration. 56.19062 Section...Procedures § 56.19062 Maximum acceleration and deceleration. Maximum normal operating acceleration and deceleration shall not exceed...

2014-07-01

360

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

361

40 CFR 35.2205 - Maximum allowable project cost.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 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)...

2014-07-01

362

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

363

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

364

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

365

16 CFR 1505.7 - Maximum acceptable surface temperatures.  

Code of Federal Regulations, 2014 CFR

... false Maximum acceptable surface temperatures. 1505.7 Section 1505.7 Commercial...1505.7 Maximum acceptable surface temperatures. The maximum acceptable surface temperatures for electrically operated toys...

2014-01-01

366

16 CFR 1505.7 - Maximum acceptable surface temperatures.  

Code of Federal Regulations, 2011 CFR

... false Maximum acceptable surface temperatures. 1505.7 Section 1505.7 Commercial...1505.7 Maximum acceptable surface temperatures. The maximum acceptable surface temperatures for electrically operated toys...

2011-01-01

367

16 CFR 1505.7 - Maximum acceptable surface temperatures.  

Code of Federal Regulations, 2012 CFR

... false Maximum acceptable surface temperatures. 1505.7 Section 1505.7 Commercial...1505.7 Maximum acceptable surface temperatures. The maximum acceptable surface temperatures for electrically operated toys...

2012-01-01

368

16 CFR 1505.7 - Maximum acceptable surface temperatures.  

Code of Federal Regulations, 2010 CFR

... false Maximum acceptable surface temperatures. 1505.7 Section 1505.7 Commercial...1505.7 Maximum acceptable surface temperatures. The maximum acceptable surface temperatures for electrically operated toys...

2010-01-01

369

16 CFR 1505.7 - Maximum acceptable surface temperatures.  

Code of Federal Regulations, 2013 CFR

... false Maximum acceptable surface temperatures. 1505.7 Section 1505.7 Commercial...1505.7 Maximum acceptable surface temperatures. The maximum acceptable surface temperatures for electrically operated toys...

2013-01-01

370

A global maximum power point tracking DC-DC converter  

E-print Network

This thesis describes the design, and validation of a maximum power point tracking DC-DC converter capable of following the true global maximum power point in the presence of other local maximum. It does this without the ...

Duncan, Joseph, 1981-

2005-01-01

371

33 CFR 183.35 - Maximum weight capacity: Outboard boats.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Maximum weight capacity: Outboard boats. 183.35 ...EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is...

2011-07-01

372

33 CFR 183.35 - Maximum weight capacity: Outboard boats.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Maximum weight capacity: Outboard boats. 183.35 ...EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is...

2010-07-01

373

Changes in the Species Composition of the Fish Community in a Reach of the Kootenai River, Idaho, after Construction of Libby Dam  

Microsoft Academic Search

I evaluated fish community structure and the density and growth of mountain whitefish (Prosopium williamsoni) downstream of Libby Dam in a 1.0-km reach of the Kootenai River, Idaho, in 1994 and compared the results with those of a similar study in 1980, after closure of the dam. In 1980 seven species of fish were collected; mountain whitefish comprised 70% of

Vaughn L. Paragamian

2002-01-01

374

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

375

On the maximum drawdown during speculative bubbles  

NASA Astrophysics Data System (ADS)

A taxonomy of large financial crashes proposed in the literature locates the burst of speculative bubbles due to endogenous causes in the framework of extreme stock market crashes, defined as falls of market prices that are outlier with respect to the bulk of drawdown price movement distribution. This paper goes on deeper in the analysis providing a further characterization of the rising part of such selected bubbles through the examination of drawdown and maximum drawdown movement of indices prices. The analysis of drawdown duration is also performed and it is the core of the risk measure estimated here.

Rotundo, Giulia; Navarra, Mauro

2007-08-01

376

Design of toroidal transformers for maximum efficiency  

NASA Technical Reports Server (NTRS)

The design of the most efficient toroidal transformer that can be built given the frequency, volt-ampere rating, magnetic flux density, window fill factor, and materials is described. With the above all held constant and only the dimensions of the magnetic core varied, the most efficient design occurs when the copper losses equal 60 percent of the iron losses. When this criterion is followed, efficiency is only slightly dependent on design frequency and fill factor. The ratios of inside diameter to outside diameter and height to build of the magnetic core that result in transformers of maximum efficiency are computed.

Dayton, J. A., Jr.

1972-01-01

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 profit performance of an absorption refrigerator  

SciTech Connect

The operation of an absorption refrigerator is viewed as a production process with exergy as its output. The relations between the optimal profit and COP (coefficient of performance), and the COP bound at the maximum profit of the refrigerator are derived based on a general heat transfer law. The results provide a theoretical basis for developing and utilizing a variety of absorption refrigerators. The focus of this paper is to search the compromise optimization between economics (profit) and the utilization factor (COP) for finite-time endoreversible thermodynamic cycles.

Chen, L.; Sun, F. [Naval Academy of Engineering, Wuhan (China)] [Naval Academy of Engineering, Wuhan (China); Wu, C. [Naval Academy, Annapolis, MD (United States). Mechanical Engineering Dept.] [Naval Academy, Annapolis, MD (United States). Mechanical Engineering Dept.

1996-12-01

379

How large is the Knudsen number reached in fluid dynamical simulations of ultrarelativistic heavy ion collisions?  

E-print Network

We investigate the applicability of fluid dynamics in ultrarelativistic heavy ion (AA) collisions and high multiplicity proton nucleus (pA) collisions. In order for fluid dynamics to be applicable the microscopic and macroscopic distance/time scales of the system have to be sufficiently separated. The degree of separation is quantified by the ratio between these scales, usually referred to as the Knudsen number. In this work, we calculate the Knudsen numbers reached in fluid dynamical simulations of AA and pA collisions at RHIC and LHC energies. For this purpose, we consider different choices of shear viscosity parametrizations, initial states and initialization times. We then estimate the values of shear viscosity for which the fluid dynamical description of ultrarelativistic AA and pA collisions breaks down. In particular, we study how such values depend on the centrality, in the case of AA collision, and multiplicity, in the case of pA collision. We found that the maximum viscosity in AA collisions is of the order $\\eta/s \\sim 0.1 \\ldots 0.2$, which is similar in magnitude to the viscosities currently employed in simulations of heavy ion collisions. For pA collisions, we found that such limit is significantly lower, being less than $\\eta/s=0.08$

H. Niemi; G. S. Denicol

2014-04-29

380

How large is the Knudsen number reached in fluid dynamical simulations of ultrarelativistic heavy ion collisions?  

E-print Network

We investigate the applicability of fluid dynamics in ultrarelativistic heavy ion (AA) collisions and high multiplicity proton nucleus (pA) collisions. In order for fluid dynamics to be applicable the microscopic and macroscopic distance/time scales of the system have to be sufficiently separated. The degree of separation is quantified by the ratio between these scales, usually referred to as the Knudsen number. In this work, we calculate the Knudsen numbers reached in fluid dynamical simulations of AA and pA collisions at RHIC and LHC energies. For this purpose, we consider different choices of shear viscosity parametrizations, initial states and initialization times. We then estimate the values of shear viscosity for which the fluid dynamical description of ultrarelativistic AA and pA collisions breaks down. In particular, we study how such values depend on the centrality, in the case of AA collision, and multiplicity, in the case of pA collision. We found that the maximum viscosity in AA collisions is of t...

Niemi, H

2014-01-01

381

Do persistent organic pollutants reach a thermodynamic equilibrium in the global environment?  

PubMed

Equilibrium partitioning between different environmental media is one of the main driving forces that govern the environmental fate of organic chemicals. In the global environment, equilibrium partitioning is in competition with long-range transport, advective phase transfer processes such as wet deposition, and degradation. Here we investigate under what conditions equilibrium partitioning is strong enough to control the global distribution of organic chemicals. We use a global multimedia mass-balance model to calculate the Globally Balanced State (GBS) of organic chemicals. The GBS is the state where equilibrium partitioning is in balance with long-range transport; it represents the maximum influence of thermodynamic driving forces on the global distribution of a chemical. Next, we compare the GBS with the Temporal Remote State, which represents the long-term distribution of a chemical in the global environment when the chemical's distribution is influenced by all transport and degradation processes in combination. This comparison allows us to identify the chemical properties required for a substance to reach the GBS as a stable global distribution. We find that thermodynamically controlled distributions are rare and do not occur for most Persistent Organic Pollutants. They are only found for highly volatile and persistent substances, such as chlorofluorocarbons. Furthermore, we find that the thermodynamic cold-trap effect (i.e., accumulation of pollutants at the poles because of reduced vapor pressure at low temperatures) is often strongly attenuated by atmospheric and oceanic long-range transport. PMID:24654605

Schenker, Sebastian; Scheringer, Martin; Hungerbühler, Konrad

2014-05-01

382

Maximum gravitational-wave energy emissible in magnetar flares  

NASA Astrophysics Data System (ADS)

Recent searches of gravitational-wave data raise the question of what maximum gravitational-wave energies could be emitted during gamma-ray flares of highly magnetized neutron stars (magnetars). The highest energies (˜1049erg) predicted so far come from a model [K. Ioka, Mon. Not. R. Astron. Soc.MNRAA40035-8711 327, 639 (2001), http://adsabs.harvard.edu/abs/2001MNRAS.327..639I] in which the internal magnetic field of a magnetar experiences a global reconfiguration, changing the hydromagnetic equilibrium structure of the star and tapping the gravitational potential energy without changing the magnetic potential energy. The largest energies in this model assume very special conditions, including a large change in moment of inertia (which was observed in at most one flare), a very high internal magnetic field, and a very soft equation of state. Here we show that energies of 1048-1049erg are possible under more generic conditions by tapping the magnetic energy, and we note that similar energies may also be available through cracking of exotic solid cores. Current observational limits on gravitational waves from magnetar fundamental modes are just reaching these energies and will beat them in the era of advanced interferometers.

Corsi, Alessandra; Owen, Benjamin J.

2011-05-01

383

Maximum gravitational-wave energy emissible in magnetar flares  

SciTech Connect

Recent searches of gravitational-wave data raise the question of what maximum gravitational-wave energies could be emitted during gamma-ray flares of highly magnetized neutron stars (magnetars). The highest energies ({approx}10{sup 49} erg) predicted so far come from a model [K. Ioka, Mon. Not. R. Astron. Soc. 327, 639 (2001), http://adsabs.harvard.edu/abs/2001MNRAS.327..639I] in which the internal magnetic field of a magnetar experiences a global reconfiguration, changing the hydromagnetic equilibrium structure of the star and tapping the gravitational potential energy without changing the magnetic potential energy. The largest energies in this model assume very special conditions, including a large change in moment of inertia (which was observed in at most one flare), a very high internal magnetic field, and a very soft equation of state. Here we show that energies of 10{sup 48}-10{sup 49} erg are possible under more generic conditions by tapping the magnetic energy, and we note that similar energies may also be available through cracking of exotic solid cores. Current observational limits on gravitational waves from magnetar fundamental modes are just reaching these energies and will beat them in the era of advanced interferometers.

Corsi, Alessandra; Owen, Benjamin J. [LIGO Laboratory, California Institute of Technology, MS 100-36, Pasadena, California 91125 (United States); Center for Gravitational Wave Physics, Institute for Gravitation and the Cosmos, Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802 (United States) and Max Planck Institut fuer Gravitationsphysik (Albert Einstein Institut), Callinstr. 38, 30167 Hannover (Germany)

2011-05-15

384

Seventh meeting of the Global Alliance to Eliminate Lymphatic Filariasis: reaching the vision by scaling up, scaling down, and reaching out  

PubMed Central

This report summarizes the 7th meeting of the Global Alliance to Eliminate Lymphatic Filariasis (GAELF), Washington DC, November 18–19, 2012. The theme, “A Future Free of Lymphatic Filariasis: Reaching the Vision by Scaling Up, Scaling Down and Reaching Out”, emphasized new strategies and partnerships necessary to reach the 2020 goal of elimination of lymphatic filariasis (LF) as a public-health problem. PMID:24450283

2014-01-01

385

Living bacteria rheology: Population growth, aggregation patterns, and collective behavior under different shear flows  

NASA Astrophysics Data System (ADS)

The activity of growing living bacteria was investigated using real-time and in situ rheology—in stationary and oscillatory shear. Two different strains of the human pathogen Staphylococcus aureus—strain COL and its isogenic cell wall autolysis mutant, RUSAL9—were considered in this work. For low bacteria density, strain COL forms small clusters, while the mutant, presenting deficient cell separation, forms irregular larger aggregates. In the early stages of growth, when subjected to a stationary shear, the viscosity of the cultures of both strains increases with the population of cells. As the bacteria reach the exponential phase of growth, the viscosity of the cultures of the two strains follows different and rich behaviors, with no counterpart in the optical density or in the population's colony-forming units measurements. While the viscosity of strain COL culture keeps increasing during the exponential phase and returns close to its initial value for the late phase of growth, where the population stabilizes, the viscosity of the mutant strain culture decreases steeply, still in the exponential phase, remains constant for some time, and increases again, reaching a constant plateau at a maximum value for the late phase of growth. These complex viscoelastic behaviors, which were observed to be shear-stress-dependent, are a consequence of two coupled effects: the cell density continuous increase and its changing interacting properties. The viscous and elastic moduli of strain COL culture, obtained with oscillatory shear, exhibit power-law behaviors whose exponents are dependent on the bacteria growth stage. The viscous and elastic moduli of the mutant culture have complex behaviors, emerging from the different relaxation times that are associated with the large molecules of the medium and the self-organized structures of bacteria. Nevertheless, these behaviors reflect the bacteria growth stage.

Patrício, P.; Almeida, P. L.; Portela, R.; Sobral, R. G.; Grilo, I. R.; Cidade, T.; Leal, C. R.

2014-08-01

386

Living bacteria rheology: population growth, aggregation patterns and cooperative behaviour under different shear flows  

E-print Network

The activity of growing living bacteria was investigated using real-time and in situ rheology -- in stationary and oscillatory shear. Two different strains of the human pathogen Staphylococcus aureus -- strain COL and its isogenic cell wall autolysis mutant -- were considered in this work. For low bacteria density, strain COL forms small clusters, while the mutant, presenting deficient cell separation, forms irregular larger aggregates. In the early stages of growth, when subjected to a stationary shear, the viscosity of both strains increases with the population of cells. As the bacteria reach the exponential phase of growth, the viscosity of the two strains follow different and rich behaviours, with no counterpart in the optical density or in the population's colony forming units measurements. While the viscosity of strain COL keeps increasing during the exponential phase and returns close to its initial value for the late phase of growth, where the population stabilizes, the viscosity of the mutant strain decreases steeply, still in the exponential phase, remains constant for some time and increases again, reaching a constant plateau at a maximum value for the late phase of growth. These complex viscoelastic behaviours, which were observed to be shear stress dependent, are a consequence of two coupled effects: the cell density continuous increase and its changing interacting properties. The viscous and elastic moduli of strain COL, obtained with oscillatory shear, exhibit power-law behaviours whose exponent are dependent on the bacteria growth stage. The viscous and elastic moduli of the mutant have complex behaviours, emerging from the different relaxation times that are associated with the large molecules of the medium and the self-organized structures of bacteria. These behaviours reflect nevertheless the bacteria growth stage.

P. Patricio; P. L. Almeida; R. Portela; R. G. Sobral; I. R. Grilo; T. Cidade; C. R. Leal

2014-03-06

387

Maximum likelihood estimation of population parameters  

SciTech Connect

One of the most important parameters in population genetics is [theta] = 4N[sub e][mu] where N[sub e] is the effective population size and [mu] is the rate of mutation per gene per generation. The authors study two related problems, using the maximum likelihood method and the theory of coalescence. One problem is the potential improvement of accuracy in estimating the parameter [theta] over existing methods and the other is the estimation of parameter [lambda] which is the ratio of two [theta]'s. The minimum variances serve as the lower bounds of the variances of all possible estimates of [theta] in practice. The authors then show that Watterson's estimate of [theta] based on the number of segregating sites is asymptotically an optimal estimate of [theta]. However, for a finite sample of sequences, substantial improvement over Watterson's estimate is possible when [theta] is large. The maximum likelihood estimate of [lambda] = [theta][sub 1]/[theta][sub 2] is obtained and the properties of the estimate are discussed. 9 refs., 3 figs., 3 tabs.

Fu, Y.X.; Li, W.H. (Univ. of Texas, Houston, TX (United States))

1993-08-01

388

Maximum likelihood estimation of population parameters.  

PubMed

One of the most important parameters in population genetics is theta = 4Ne mu where Ne is the effective population size and mu is the rate of mutation per gene per generation. We study two related problems, using the maximum likelihood method and the theory of coalescence. One problem is the potential improvement of accuracy in estimating the parameter theta over existing methods and the other is the estimation of parameter lambda which is the ratio of two theta's. The minimum variances of estimates of the parameter theta are derived under two idealized situations. These minimum variances serve as the lower bounds of the variances of all possible estimates of theta in practice. We then show that Watterson's estimate of theta based on the number of segregating sites is asymptotically an optimal estimate of theta. However, for a finite sample of sequences, substantial improvement over Watterson's estimate is possible when theta is large. The maximum likelihood estimate of lambda = theta 1/theta 2 is obtained and the properties of the estimate are discussed. PMID:8375660

Fu, Y X; Li, W H

1993-08-01

389

Maximum likelihood decoding of Reed Solomon Codes  

SciTech Connect

We present a randomized algorithm which takes as input n distinct points ((x{sub i}, y{sub i})){sup n}{sub i=1} from F x F (where F is a field) and integer parameters t and d and returns a list of all univariate polynomials f over F in the variable x of degree at most d which agree with the given set of points in at least t places (i.e., y{sub i} = f (x{sub i}) for at least t values of i), provided t = {Omega}({radical}nd). The running time is bounded by a polynomial in n. This immediately provides a maximum likelihood decoding algorithm for Reed Solomon Codes, which works in a setting with a larger number of errors than any previously known algorithm. To the best of our knowledge, this is the first efficient (i.e., polynomial time bounded) algorithm which provides some maximum likelihood decoding for any efficient (i.e., constant or even polynomial rate) code.

Sudan, M. [IBM Thomas J. Watson Research Center, Yorktown Heights, NY (United States)

1996-12-31

390

Maximum Diameter of Impacting Liquid Droplets  

NASA Astrophysics Data System (ADS)

The maximum diameter a droplet that impacts on a surface will attain is the subject of controversy, notably for high-velocity impacts of low-viscosity liquids such as water or blood. We study the impact of droplets of simple liquids of different viscosities, and a shear-thinning complex fluid (blood), for a wide range of surfaces, impact speeds, and impact angles. We show that the spreading behavior cannot simply be predicted by equating the inertial to either capillary or viscous forces, since, for most situations of practical interest, all three forces are important. We determine the correct scaling behaviors for the viscous and capillary regimes and, by interpolating between the two, allow for a universal rescaling. The results for different impact angles can be rescaled on this universal curve also, by doing a simple geometrical correction for the impact angle. For blood, we show that the shear-thinning properties do not affect the maximum diameter and only the high-shear rate viscosity is relevant. With our study, we solve a long-standing problem within the fluid-dynamics community: We attest that the spreading behavior of droplets is governed by the conversion of kinetic energy into surface energy or dissipated heat. Energy transfer into internal flows marginally hinders droplet spreading upon impact.

Laan, Nick; de Bruin, Karla G.; Bartolo, Denis; Josserand, Christophe; Bonn, Daniel

2014-10-01

391

3D Multi-Cell Simulation of Tumor Growth and Angiogenesis  

PubMed Central

We present a 3D multi-cell simulation of a generic simplification of vascular tumor growth which can be easily extended and adapted to describe more specific vascular tumor types and host tissues. Initially, tumor cells proliferate as they take up the oxygen which the pre-existing vasculature supplies. The tumor grows exponentially. When the oxygen level drops below a threshold, the tumor cells become hypoxic and start secreting pro-angiogenic factors. At this stage, the tumor reaches a maximum diameter characteristic of an avascular tumor spheroid. The endothelial cells in the pre-existing vasculature respond to the pro-angiogenic factors both by chemotaxing towards higher concentrations of pro-angiogenic factors and by forming new blood vessels via angiogenesis. The tumor-induced vasculature increases the growth rate of the resulting vascularized solid tumor compared to an avascular tumor, allowing the tumor to grow beyond the spheroid in these linear-growth phases. First, in the linear-spherical phase of growth, the tumor remains spherical while its volume increases. Second, in the linear-cylindrical phase of growth the tumor elongates into a cylinder. Finally, in the linear-sheet phase of growth, tumor growth accelerates as the tumor changes from cylindrical to paddle-shaped. Substantial periods during which the tumor grows slowly or not at all separate the exponential from the linear-spherical and the linear-spherical from the linear-cylindrical growth phases. In contrast to other simulations in which avascular tumors remain spherical, our simulated avascular tumors form cylinders following the blood vessels, leading to a different distribution of hypoxic cells within the tumor. Our simulations cover time periods which are long enough to produce a range of biologically reasonable complex morphologies, allowing us to study how tumor-induced angiogenesis affects the growth rate, size and morphology of simulated tumors. PMID:19834621

Shirinifard, Abbas; Gens, J. Scott; Zaitlen, Benjamin L.; Pop?awski, Nikodem J.; Swat, Maciej; Glazier, James A.

2009-01-01

392

Population demographics of catostomids in large river ecosystems: effects of discharge and temperature on recruitment dynamics and growth  

USGS Publications Warehouse

Catostomids are among the most widespread and ecologically important groups of fishes in North America, particularly in large river systems. Despite their importance, little information is available on their population demographics and even less is known about factors influencing their population dynamics. The objectives of this study were to describe annual mortality, recruitment variation, and growth of eight catostomid species, and to evaluate the effects of discharge and temperature on year-class strength and growth in Iowa rivers. Catostomids were sampled from 3-km reaches in four nonwadable rivers during June–August 2009. Northern hogsucker, Hypentelium nigricans, golden redhorse, Moxostoma erythrurum, and shorthead redhorse, M. macrolepidotum, typically lived 6–8 years, had very stable recruitment, and had high total annual mortality (i.e., 40–60%). Golden redhorse exhibited the fastest growth of all species. Growth of northern hogsucker and shorthead redhorse was intermediate to the other catostomids. Highfin carpsucker, Carpiodes velifer, quillback, Carpiodes cyprinus, and white sucker, Catostomus commersonii, had high growth rates, low mortality (i.e., 25–30%), and relatively stable recruitment. River carpsucker, Carpiodes carpio, and silver redhorse, M. anisurum, had higher maximum ages (up to age 11), slower growth, lower total annual mortality (20–25%), and higher recruitment variability than the other species. Neither discharge nor temperature was strongly related to recruitment of catostomids. In contrast, several interesting patterns were observed with regard to growth. Species (e.g., carpsuckers, Carpiodes spp.) that typically consume prey items most common in fine substrates (e.g., chironomids) had higher growth rates in reaches dominated by sand and silt substrate. Species (e.g., northern hogsucker) that consume prey associated with large substrates (e.g., plecopterans) had much faster growth in reaches with a high proportion of rocky substrates. Temperature was weakly related to growth of catostomids; however, discharge explained a substantial amount of the variation in growth of nearly all species. Results of this study provide important information on the autecology of catostomids that can be used for comparison among species and systems. These data also suggest that connection of rivers with their floodplain is an important feature for catostomids in temperate river systems.

Quist, M.C.; Spiegel, J.R.

2011-01-01

393

Continuous cultivation of recombinant Escherichia coli: Existence of an optimum dilution rate for maximum plasmid and gene product concentration.  

PubMed

Growth yield factors, plasmid stability, cellular plasmid content, and cloned gene product activity for Escherichia coli HB101 containing plasmid pDM246 were measured at several dilution rates in continuous culture. Cell mass yield per mass of glucose consumed declined with increasing dilution rate. There was no evidence of plasmid segregational instability in any experiments, none of which employed selective medium. Plasmid content per cell varied with population-specific growth rate as observed in earlier batch experiments with the same strain. Plasmid content declined with increasing specific growth rate following indication of a maximum number of plasmids per cell at specific growth rates of ca. 0.3 h(-1). Cloned gene product (beta-lactamase) activity exhibited a sharp maximum with respect to dilution rate in continuous culture. Qualitatively different results were observed in previous experiments in batch cultivation in which specific growth rate changes were effected by altering medium composition. PMID:18553877

Seo, J H; Bailey, J E

1986-10-01

394

Better Algorithms and Bounds for Directed Maximum Leaf Problems  

E-print Network

Better Algorithms and Bounds for Directed Maximum Leaf Problems Noga Alon 1 , Fedor V. Fomin 2 of Mathematical Sciences Chennai, 600 017, India saket@imsc.res.in Abstract. The Directed Maximum Leaf Out Maximum Leaf Out­Branching problem is to find an out­branching in a given digraph with the maximum number

Krivelevich, Michael

395

Maximum screening fields of superconducting multilayer structures  

E-print Network

It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields $H_s$ of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness $\\sim 0.1\\; \\mu$m at the Nb surface could increase $H_s\\simeq 240$ mT of a clean Nb up to $H_s\\simeq 290$ mT. Optimized multilayers of Nb$_3$Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

Gurevich, Alex

2015-01-01

396

Diffusivity maximum in a reentrant nematic phase.  

PubMed

We report molecular dynamics simulations of confined liquid crystals using the Gay-Berne-Kihara model. Upon isobaric cooling, the standard sequence of isotropic-nematic-smectic A phase transitions is found. Upon further cooling a reentrant nematic phase occurs. We investigate the temperature dependence of the self-diffusion coefficient of the fluid in the nematic, smectic and reentrant nematic phases. We find a maximum in diffusivity upon isobaric cooling. Diffusion increases dramatically in the reentrant phase due to the high orientational molecular order. As the temperature is lowered, the diffusion coefficient follows an Arrhenius behavior. The activation energy of the reentrant phase is found in reasonable agreement with the reported experimental data. We discuss how repulsive interactions may be the underlying mechanism that could explain the occurrence of reentrant nematic behavior for polar and non-polar molecules. PMID:22837730

Stieger, Tillmann; Mazza, Marco G; Schoen, Martin

2012-01-01

397

Diffusivity Maximum in a Reentrant Nematic Phase  

PubMed Central

We report molecular dynamics simulations of confined liquid crystals using the Gay–Berne–Kihara model. Upon isobaric cooling, the standard sequence of isotropic–nematic–smectic A phase transitions is found. Upon further cooling a reentrant nematic phase occurs. We investigate the temperature dependence of the self-diffusion coefficient of the fluid in the nematic, smectic and reentrant nematic phases. We find a maximum in diffusivity upon isobaric cooling. Diffusion increases dramatically in the reentrant phase due to the high orientational molecular order. As the temperature is lowered, the diffusion coefficient follows an Arrhenius behavior. The activation energy of the reentrant phase is found in reasonable agreement with the reported experimental data. We discuss how repulsive interactions may be the underlying mechanism that could explain the occurrence of reentrant nematic behavior for polar and non-polar molecules. PMID:22837730

Stieger, Tillmann; Mazza, Marco G.; Schoen, Martin

2012-01-01

398

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

399

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

400

Unidimensional games, propitious environments, and maximum diversity  

NASA Astrophysics Data System (ADS)

Cellular automata have been extensively used in the modeling of complexity. In biological phenomena complexity is directly related to the intuitive concept of diversity, which manifests itself in several forms. Particularly, the game Life [E. R. Berlekamp, J. H. Conway, and R. K. Guy, Winning Ways for Your Mathematical Plays (Academic, New York, 1982), Vol. 2] may be viewed as a picture of nonlinear open biological systems acting cooperatively. However, it has been shown that, in Life, diversity (defined in terms of different clusters) decreases with time. We derive an alternative game introducing the concept of a propitious environment which confers longevity to live sites in time evolution. It is shown that the game self-organizes in a configuration of maximum diversity exhibiting a high geometrical complexity. This game is considered in one dimension and has some connections with the unidimensional Life.

Sales, Tasso R. M.

1993-10-01

401

Maximum screening fields of superconducting multilayer structures  

NASA Astrophysics Data System (ADS)

It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields Hs of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness ˜0.1 ?m at the Nb surface could increase Hs ? 240 mT of a clean Nb up to Hs ? 290 mT. Optimized multilayers of Nb3Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.

Gurevich, Alex

2015-01-01

402

Maximum entropy model for business cycle synchronization  

NASA Astrophysics Data System (ADS)

The global economy is a complex dynamical system, whose cyclical fluctuations can mainly be characterized by simultaneous recessions or expansions of major economies. Thus, the researches on the synchronization phenomenon are key to understanding and controlling the dynamics of the global economy. Based on a pairwise maximum entropy model, we analyze the business cycle synchronization of the G7 economic system. We obtain a pairwise-interaction network, which exhibits certain clustering structure and accounts for 45% of the entire structure of the interactions within the G7 system. We also find that the pairwise interactions become increasingly inadequate in capturing the synchronization as the size of economic system grows. Thus, higher-order interactions must be taken into account when investigating behaviors of large economic systems.

Xi, Ning; Muneepeerakul, Rachata; Azaele, Sandro; Wang, Yougui

2014-11-01

403

Maximum mass of magnetic white dwarfs  

E-print Network

We revisit in this work the problem of the maximum masses of magnetized White Dwarfs (WD). The impact of a strong magnetic field onto the structure equations is addressed. The pressures become anisotropic due to the presence of the magnetic field and split into a parallel and perpendicular components. We first construct stable solutions of TOV equations for the parallel pressures, and found that physical solutions vanish for the perpendicular pressure when $B \\gtrsim 10^{13}$ G. This fact establishes an upper bound for a magnetic field and the stability of the configurations in the (quasi) spherical approximation. Our findings also indicate that it is not possible to obtain stable magnetized WD with super Chandrasekhar masses because the values of the magnetic field needed for them are higher than this bound. To proceed into the anisotropic regime, we derived structure equations appropriated for a cylindrical metric with anisotropic pressures. From the solutions of the structure equations in cylindrical symme...

Paret, D Manreza; Horvath, J E

2015-01-01

404

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. PMID:24701144

Zhan, Yongzhao; Shen, Xiangjun; Du, Lan

2014-01-01

405

Maximum life spiral bevel reduction design  

NASA Technical Reports Server (NTRS)

Optimization is applied to the design of a spiral bevel gear reduction for maximum life at a given size. 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 values. Gear tooth bending strength and minimum contact ratio under load are included in the active constraints. The optimal design of the spiral bevel gear reduction includes the selection of bearing and shaft proportions in addition to gear mesh parameters. System life is maximized subject to a fixed backcone distance of the spiral bevel gear set for a specified speed reduction, shaft angle, input torque, and power. Design examples show the influence of the bearing lives on the gear parameters in the optimal configurations. For a fixed back-cone distance, optimal designs with larger shaft angles have larger service lives.

Savage, M.; Prasanna, M. G.; Coe, H. H.

1992-01-01

406

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

407

ILP-based maximum likelihood genome scaffolding  

PubMed Central

Background Interest in de novo genome assembly has been renewed in the past decade due to rapid advances in high-throughput sequencing (HTS) technologies which generate relatively short reads resulting in highly fragmented assemblies consisting of contigs. Additional long-range linkage information is typically used to orient, order, and link contigs into larger structures referred to as scaffolds. Due to library preparation artifacts and erroneous mapping of reads originating from repeats, scaffolding remains a challenging problem. In this paper, we provide a scalable scaffolding algorithm (SILP2) employing a maximum likelihood model capturing read mapping uncertainty and/or non-uniformity of contig coverage which is solved using integer linear programming. A Non-Serial Dynamic Programming (NSDP) paradigm is applied to render our algorithm useful in the processing of larger mammalian genomes. To compare scaffolding tools, we employ novel quantitative metrics in addition to the extant metrics in the field. We have also expanded the set of experiments to include scaffolding of low-complexity metagenomic samples. Results SILP2 achieves better scalability throughg a more efficient NSDP algorithm than previous release of SILP. The results show that SILP2 compares favorably to previous methods OPERA and MIP in both scalability and accuracy for scaffolding single genomes of up to human size, and significantly outperforms them on scaffolding low-complexity metagenomic samples. Conclusions Equipped with NSDP, SILP2 is able to scaffold large mammalian genomes, resulting in the longest and most accurate scaffolds. The ILP formulation for the maximum likelihood model is shown to be flexible enough to handle metagenomic samples. PMID:25253180

2014-01-01

408

The Maximum Mass of Star Clusters  

E-print Network

When an universal untruncated star cluster initial mass function (CIMF) described by a power-law distribution is assumed, the mass of the most massive star cluster in a galaxy (M_max) is the result of the size-of-sample (SoS) effect. This implies a dependence of M_max on the total number of star clusters (N). The SoS effect also implies that M_max within a cluster population increases with equal logarithmic intervals of age. This is because the number of clusters formed in logarithmic age intervals increases (assuming a constant cluster formation rate). This effect has been observed in the SMC and LMC. Based on the maximum pressure (P_int) inside molecular clouds, it has been suggested that a physical maximum mass (M_max[phys]) should exist. The theory predicts that M_max[phys] should be observable, i.e. lower than M_max that follows from statistical arguments, in big galaxies with a high star formation rate. We compare the SoS relations in the SMC and LMC with the ones in M51 and model the integrated cluster luminosity function (CLF) for two cases: 1) M_max is determined by the SoS effect and 2) M_max=M_max[phys]=constant. The observed CLF of M51 and the comparison of the SoS relations with the SMC and LMC both suggest that there exists a M_max[phys] of 5*10^5 M_sun in M51. The CLF of M51 looks very similar to the one observed in the ``Antennae'' galaxies. A direct comparison with our model suggests that there M_max[phys]=2*10^6 M_sun.

M. Gieles; S. S. Larsen; M. R. Haas; R. A. Scheepmaker; N. Bastian

2006-04-27

409

DOWN-STREAM SPATIAL DISTRIBUTION OF ANTIBIOTIC RESISTANCE TRAITS ALONG METAL CONTAMINATED STREAM REACHES  

SciTech Connect

Sediment bacteria samples were collected from three streams in South Carolina, two contaminated with multiple metals (Four Mile Creek and Castor Creek), one uncontaminated (Meyers Branch), and another metal contaminated stream (Lampert Creek) in northern Washington State. Growth plates inoculated with Four Mile Creek sample extracts show bacteria colony growth after incubation on plates containing either one of two aminoglycosides (kanamycin or streptomycin), tetracycline or chloramphenocol. This study analyzes the spatial pattern of antibiotic resistance in culturable sediment bacteria in all four streams that may be due to metal contamination. We summarize the two aminoglycoside resistance measures and the 10 metals concentrations by Principal Components Analysis. Respectively, 63% and 58% of the variability was explained in the 1st principal component of each variable set. We used the respective multivariate summary metrics (i.e. 1st principal component scores) as input measures for exploring the spatial correlation between antibiotic resistance and metal concentration for each stream reach sampled. Results show a significant and negative correlation between metals scores versus aminoglycoside resistance scores and suggest that selection for metal tolerance among sediment bacteria may influence selection for antibiotic resistance differently than previously supposed.. In addition, we borrow a method from geostatistics (variography) wherein a spatial cross-correlation analysis shows that decreasing metal concentrations scores are associated with increasing aminoglycoside resistance scores as the separation distance between sediment samples decreases, but for contaminated streams only. Since these results were counter to our initial expectation and to other experimental evidence for water column bacteria, we suspect our field results are influenced by metal bioavailability in the sediments and by a contaminant promoted interaction or ''cocktail effect'' from complex combinations of pollution mediated selection agents.

Tuckfield, C; J V Mcarthur (NOEMAIL), J

2007-04-16

410

Handling Temperature Bursts Reaching 464°C: Different Microbial Strategies in the Sisters Peak Hydrothermal Chimney  

PubMed Central

The active venting Sisters Peak (SP) chimney on the Mid-Atlantic Ridge holds the current temperature record for the hottest ever measured hydrothermal fluids (400°C, accompanied by sudden temperature bursts reaching 464°C). Given the unprecedented temperature regime, we investigated the biome of this chimney with a focus on special microbial adaptations for thermal tolerance. The SP metagenome reveals considerable differences in the taxonomic composition from those of other hydrothermal vent and subsurface samples; these could be better explained by temperature than by other available abiotic parameters. The most common species to which SP genes were assigned were thermophilic Aciduliprofundum sp. strain MAR08-339 (11.8%), Hippea maritima (3.8%), Caldisericum exile (1.5%), and Caminibacter mediatlanticus (1.4%) as well as to the mesophilic Niastella koreensis (2.8%). A statistical analysis of associations between taxonomic and functional gene assignments revealed specific overrepresented functional categories: for Aciduliprofundum, protein biosynthesis, nucleotide metabolism, and energy metabolism genes; for Hippea and Caminibacter, cell motility and/or DNA replication and repair system genes; and for Niastella, cell wall and membrane biogenesis genes. Cultured representatives of these organisms inhabit different thermal niches; i.e., Aciduliprofundum has an optimal growth temperature of 70°C, Hippea and Caminibacter have optimal growth temperatures around 55°C, and Niastella grows between 10 and 37°C. Therefore, we posit that the different enrichment profiles of functional categories reflect distinct microbial strategies to deal with the different impacts of the local sudden temperature bursts in disparate regions of the chimney. PMID:24837379

Kurtz, Stefan; LaRoche, Julie

2014-01-01

411

Low-level nocturnal wind maximum over the Central Amazon Basin  

NASA Technical Reports Server (NTRS)

A low-level nocturnal wind maximum is shown to exist over extensive and nearly undisturbed rainforest near the central Amazon city of Manaus. Meteorological data indicate the presence of this nocturnal wind maximum during both the wet and dry seasons of the Central Amazon Basin. Daytime wind speeds which are characteristically 3-7 m/s between 300 and 1000 m increase to 10-15 m/s shortly after sunset. The wind-speed maximum is reached in the early evening, with wind speeds remaining high until several hours after sunrise. The nocturnal wind maximum is closely linked to a strong low-level inversion formed by radiational cooling of the rainforest canopy. Surface and low-level pressure gradients between the undisturbed forest and the large Amazon river system and the city of Manaus are shown to be responsible for much of the nocturnal wind increase. The pressure gradients are interpreted as a function of the thermal differences between undisturbed forest and the river/city. The importance of both the frictional decoupling and the horizontal pressure gradient suggest that the nocturnal wind maximum does not occur uniformly over all Amazonia. Low-level winds are thought to be pervasive under clear skies and strong surface cooling and that, in many places (i.e., near rivers), local pressure gradients enhance the low-level nocturnal winds.

Greco, Steven; Ulanski, Stanley; Garstang, Michael; Houston, Samuel

1992-01-01

412

On the maximum value of the cosmic abundance of oxygen and the oxygen yield  

E-print Network

We search for the maximum oxygen abundance in spiral galaxies. Because this maximum value is expected to occur in the centers of the most luminous galaxies, we have constructed the luminosity - central metallicity diagram for spiral galaxies, based on a large compilation of existing data on oxygen abundances of HII regions in spiral galaxies. We found that this diagram shows a plateau at high luminosities (-22.3 oxygen abundance 12+log(O/H) ~ 8.87. This provides strong evidence that the oxygen abundance in the centers of the most luminous metal-rich galaxies reaches the maximum attainable value of oxygen abundance. Since some fraction of the oxygen (about 0.08 dex) is expected to be locked into dust grains, the maximum value of the true gas+dust oxygen abundance in spiral galaxies is 12+log(O/H) ~ 8.95. This value is a factor of ~ 2 higher than the recently estimated solar value. Based on the derived maximum oxygen abundance in galaxies, we found the oxygen yield to be about 0.0035, depending on the fraction of oxygen incorporated into dust grains.

L. S. Pilyugin; T. X. Thuan; J. M. Vilchez

2007-01-11

413

Suppression of mammalian bone growth by membrane transport inhibitors.  

PubMed

Bone lengthening during skeletal growth is driven primarily by the controlled enlargement of growth plate (GP) chondrocytes. The cellular mechanisms are unclear but membrane transporters are probably involved. We investigated the role of the Na(+)/H(+) antiporter (NHE1) and anion exchanger (AE2) in bone lengthening and GP chondrocyte hypertrophy in Sprague-Dawley 7-day-old rat (P7) bone rudiments using the inhibitors EIPA (5-(N-ethyl-N-isopropyl)amiloride) and DIDS (4,4-diidothiocyano-2,2-stilbenedisulphonate), respectively. We have also determined cell-associated levels of these transporters along the GP using fluorescent immunohistochemistry (FIHC). Culture of bones with EIPA or DIDS inhibited rudiment growth (50% at approx. 250 and 25 µM, respectively). Both decreased the size of the hypertrophic zone (P < 0.05) but had no effect on overall length or cell density of the GP. In situ chondrocyte volume in proliferative and hypertrophic zones was decreased (P < 0.01) with EIPA but not DIDS. FIHC labeling of NHE1 was relatively high and constant along the GP but declined steeply in the late hypertrophic zone. In contrast, AE2 labeling was relatively low in proliferative zone cells but increased (P < 0.05) reaching a maximum in the early hypertrophic zone, before falling rapidly in the late hypertrophic zone suggesting AE2 might regulate the transition phase of chondrocytes between proliferative and hypertrophic zones. The inhibition of bone growth by EIPA may be due to a reduction to chondrocyte volume set-point. However the effect of DIDS was unclear but could result from inhibition of AE2 and blocking of the transition phase. These results demonstrate that NHE1 and AE2 are important regulators of bone growth. PMID:23059814

Loqman, Mohamad Y; Bush, Peter G; Farquharson, Colin; Hall, Andrew C

2013-03-01

414

Chandra Proves Black Hole Influence is Far Reaching  

NASA Astrophysics Data System (ADS)

Scientists using NASA's Chandra X-ray Observatory have discovered evidence of energetic plumes - particles that extend 300,000 light years into a massive cluster of galaxies. The plumes are due to explosive venting from the vicinity of a supermassive black hole, and they provide dramatic new evidence of the influence a black hole can have over intergalactic distances. "In relative terms, it is as if a heat source the size of a fingernail affects the behavior of a region the size of Earth," said Andrew Fabian of Cambridge University, U.K. Fabian is lead author of a report on this research that will appear in an upcoming issue of the Monthly Notices of the Royal Astronomical Society. Perseus Cluster Animation Perseus Cluster Animation Fabian's group discovered the plumes by studying data from 280 hours (more than 1 million seconds) of Chandra observations of the Perseus cluster, the longest X-ray observation ever taken of a galaxy cluster. The cluster contains thousands of galaxies immersed in a vast cloud of multi-million degree gas with the mass equivalent of trillions of suns. The plumes showed up in the X-ray data as low pressure regions in the hot gas extending outward from the giant galaxy in the center of the cluster. The low gas pressure measured in the plumes is likely the result of the displacement of the gas by bubbles of unseen high-energy particles. The bubbles appear to be generated by high-speed jets blasting away from the vicinity of the giant galaxy's supermassive black hole. Individual bubbles seen in the inner regions expand and merge to create vast plumes at larger distances. Chandra Image of Perseus Cluster with Overlay of Low Pressure Region Chandra Image of Perseus Cluster with Overlay of Low Pressure Region "The plumes show that the black hole has been venting for at least 100 million years, and probably much longer," said co-author Jeremy Sanders also of Cambridge University. The venting produces sound waves which heat the gas throughout the inner regions of the cluster and prevent the gas from cooling and making stars at a large rate. This process has slowed the growth of the central galaxy in the cluster, NGC 1275, which is one of the largest galaxies in the universe. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. Images and additional information about Chandra are available at: http://chandra.harvard.edu and http://chandra.nasa.gov For more information about NASA and agency programs on the Web, visit: http://www.nasa.gov

2005-12-01

415

R.E.A.C.H.ing Out to Creative Thinking.  

ERIC Educational Resources Information Center

Described is Project Reach (Reaching Educators and Actualizing Children) which is designed for gifted students, and includes exercises in productive thinking, student participation in planning, decision making, forecasting, communication, creative problem solving, and mind stretching. (KC)

Gaffron, Norma Bondeson

1980-01-01

416

5 CFR 315.703 - Employees formerly reached on a register.  

Code of Federal Regulations, 2010 CFR

...false Employees formerly reached on a register. 315.703 Section 315.703 ...703 Employees formerly reached on a register. (a) Employee coverage. An...career-conditional appointment on a register appropriate for that position may...

2010-01-01

417

5 CFR 330.505 - Nonapplicability to persons within reach on registers.  

Code of Federal Regulations, 2010 CFR

...Nonapplicability to persons within reach on registers. 330.505 Section 330.505 ...Nonapplicability to persons within reach on registers. The restrictions in this subpart...apply to a person who is within reach on a register for competitive appointment to the...

2010-01-01

418

RESEARCH ARTICLE Locomoting-to-reach: information variables and control strategies  

E-print Network

RESEARCH ARTICLE Locomoting-to-reach: information variables and control strategies for nested online: 20 September 2011 Ã? Springer-Verlag 2011 Abstract Locomoting-to-reach is a basic perception/ action behavior that requires visual information for the control of both locomotion and reaching

Bingham, Geoffrey P.

419

AMPHIBIANS AND REPTILES OF THE GREAT FALLS BYPASSED REACHES IN SOUTH CAROLINA  

E-print Network

AMPHIBIANS AND REPTILES OF THE GREAT FALLS BYPASSED REACHES IN SOUTH CAROLINA MICHAEL E. DORCAS of the amphibians and reptiles inhabiting the Great Falls Bypassed Reaches of the Catawba River in South Carolina. A list of 85 species of amphibians and reptiles potentially occurring in the Great Falls Bypassed Reaches

Dorcas, Michael E.

420

[Net ecosystem CO2 exchange and its environmental regulation mechanisms in a reed wetland in the Yellow River Delta of China during the growth season].  

PubMed

By using eddy covariance technique, this paper measured the net ecosystem CO2 exchange (NEE) in a reed (Phragmites australis) wetland in the Yellow River Delta of China during the growth season of 2011, and investigated the variation patterns of the NEE and related affecting factors. The average diurnal variation of the NEE in different months showed a U-type curve, with the maximum net CO2 uptake rate and release rate being (0.44 +/- 0.03) and (0.16 +/- 0.01) mg CO2 x m(-2) x s(-1), respectively. The NEE, ecosystem respiration (R(eco)), and gross primary productivity (GPP) were all higher in vigorous growth season (from July to September) and lower in early growth season (from May to June) and late growth season (from October to November). Both R(eco) and NEE reached their maximum values in August, while GPP reached its peak value in July. During the growth season, the ecosystem CO2 exchange was mainly dominated by photosynthetic active radiation (PAR), soil temperature (T(s)), and soil water content (SWC). There was a rectangular hyperbolic relationship between the daytime NEE and PAR. The nighttime ecosystem respiration (R(eco,n)) was exponentially correlated with the T(s) at 5 cm depth, and the temperature sensitivity of the ecosystem respiration (Q10) was 2.30. SWC and T(s) were the main factors affecting the R(eco,n). During the entire growth season, the reed wetland ecosystem in the Yellow River delta was an obvious carbon sink, with the total net carbon sequestration being 780.95 g CO2 x m(-2). PMID:24417096

Yang, Li-Qiong; Han, Guang-Xuan; Yu, Jun-Bao; Wu, Li-Xin; Zhu, Min; Xing, Qing-Hui; Wang, Guang-Mei; Mao, Pei-Li

2013-09-01

421

REACH exposure assessment of anticorrosive paint products--determination of exposure from application and service life to the aquatic environment.  

PubMed

The European Community Regulation on the registration, evaluation, authorisation and restriction of chemicals (REACH) introduced exposure scenarios describing safe use quantitatively, and enhancing the importance of scientific based exposure assessments. This paper presents methods to determine exposure from the airless spray application of anti-corrosive paint and leaching of painted articles submerged in seawater, to establish whether it is possible to test these exposures in a reproducible and feasible way. The paper also presents results from using the methods in order to assess how well the default values recommended under REACH coincide with the tested values and corresponding values available in literature. The methods used were feasible under laboratory conditions. The reproducibility of the application study was shown to be good and all analyses of the leaching showed concentrations below detection limit. More replicates will be required to validate the reproducibility of the growth inhibition tests. Measured values for the present overspray scenario were between, and the leaching values below, values from REACH guidelines and emission scenario documents. Further development of the methods is recommended. PMID:21964505

Gade, Anne Lill; Heiaas, Harald; Thomas, Kevin; Hylland, Ketil

2011-12-01

422

Radial growth of Tamarix ramosissima responds to changes in the water regime in an extremely arid region of northwestern China  

NASA Astrophysics Data System (ADS)

The response of radial growth of tamarisk ( Tamarix ramosissima) growing on the shore of West-Juyan Lake, on the Heihe River in northwestern China, to changes in the lake’s water regime was studied using tree-ring chronologies, principal components (PC) analysis, and classical correlation analysis. The first PC accounted for 53.3% of the total variance and reflected a common growth response at different sites. Correlation analysis indicated that fluctuations in the lake’s water level during the growing season (May August) was primarily responsible for variations in the radial growth of tamarisk and explained more of the variance at low-lying sites than at higher sites. The second PC accounted for 30.7% of the total variance and revealed distinct differences in growth response between low-lying sites and those on higher ground. Total annual precipitation played an important role in radial growth of tamarisk at the higher sites. The spatial pattern in the tree-ring chronologies for different sites was performed in the temporal pattern of the tree-ring chronology at the same site. Other factors such as microtopography, soil salinity, sand activity, and browsing by herbivores also affected the radial growth of tamarisk. The diversity in responses to the maximum water table depth for tamarisk in the study area appears to have been caused by local variations in precipitation, which can compensate to some degree for the inability of a plant’s roots to reach the water table.

Xiao, Shengchun; Xiao, Honglang

2007-11-01

423

Age and Growth of the Round Stingray Urotrygon rogersi, a Particularly Fast-Growing and Short-Lived Elasmobranch  

PubMed Central

We examined the age and growth of Urotrygon rogersi on the Colombian coast of the Eastern Tropical Pacific Ocean by directly estimating age using vertebral centra. We verified annual deposition of growth increments with marginal increment analysis. Eight growth curves were fitted to four data sets defined on the basis of the reproductive cycle (unadjusted or adjusted for age at first band) and size variables (disc width or total length). Model performance was evaluated using Akaike's Information Criterion (AIC), AIC weights and multi-model inference criteria. A two-phase growth function with adjusted age provided the best description of growth for females (based on five parameters, DW? ?=? 20.1 cm, k ?=? 0.22 yr–1) and males (based on four and five parameters, DW? ?=? 15.5 cm, k ?=? 0.65 yr–1). Median maturity of female and male U. rogersi is reached very fast (mean ± SE ?=? 1.0 ± 0.1 year). This is the first age and growth study for a species of the genus Urotrygon and results indicate that U. rogersi attains a smaller maximum size and has a shorter lifespan and lower median age at maturity than species of closely related genera. These life history traits are in contrast with those typically reported for other elasmobranchs. PMID:24776963

Mejía-Falla, Paola A.; Cortés, Enric; Navia, Andrés F.; Zapata, Fernando A.

2014-01-01

424

Maximum Error Modeling for Fault-Tolerant Computation using Maximum a posteriori (MAP) Hypothesis  

E-print Network

The application of current generation computing machines in safety-centric applications like implantable biomedical chips and automobile safety has immensely increased the need for reviewing the worst-case error behavior of computing devices for fault-tolerant computation. In this work, we propose an exact probabilistic error model that can compute the maximum error over all possible input space in a circuit specific manner and can handle various types of structural dependencies in the circuit. We also provide the worst-case input vector, which has the highest probability to generate an erroneous output, for any given logic circuit. We also present a study of circuit-specific error bounds for fault-tolerant computation in heterogeneous circuits using the maximum error computed for each circuit. We model the error estimation problem as a maximum a posteriori (MAP) estimate, over the joint error probability function of the entire circuit, calculated efficiently through an intelligent search of the entire input space using probabilistic traversal of a binary join tree using Shenoy-Shafer algorithm. We demonstrate this model using MCNC and ISCAS benchmark circuits and validate it using an equivalent HSpice model. Both results yield the same worst-case input vectors and the highest % difference of our error model over HSpice is just 1.23%. We observe that the maximum error probabilities are significantly larger than the average error probabilities, and provides a much tighter error bounds for fault-tolerant computation. We also find that the error estimates depend on the specific circuit structure and the maximum error probabilities are sensitive to the individual gate failure probabilities.

Karthikeyan Lingasubramanian; Syed M. Alam; Sanjukta Bhanja

2009-06-17

425

Gauging the Nearness and Size of Cycle Maximum  

NASA Technical Reports Server (NTRS)

A simple method for monitoring the nearness and size of conventional cycle maximum for an ongoing sunspot cycle is examined. The method uses the observed maximum daily value and the maximum monthly mean value of international sunspot number and the maximum value of the 2-mo moving average of monthly mean sunspot number to effect the estimation. For cycle 23, a maximum daily value of 246, a maximum monthly mean of 170.1, and a maximum 2-mo moving average of 148.9 were each observed in July 2000. Taken together, these values strongly suggest that conventional maximum amplitude for cycle 23 would be approx. 124.5, occurring near July 2002 +/-5 mo, very close to the now well-established conventional maximum amplitude and occurrence date for cycle 23-120.8 in April 2000.

Wilson, Robert M.; Hathaway, David H.

2003-01-01

426

Reaching activity in parietal area V6A of macaque: eye influence on arm activity or retinocentric coding of reaching movements?  

PubMed

Parietal area V6A contains neurons modulated by the direction of gaze as well as neurons able to code the direction of arm movement. The present study was aimed to disentangle the gaze effect from the effect of reaching activity upon single V6A neurons. To this purpose, we used a visuomotor task in which the direction of arm movement remained constant while the animal changed the direction of gaze. Gaze direction modulated reach-related activity in about two-thirds of tested neurons. In several cases, modulations were not due to the eye-position signal per se, the apparent eye-position modulation being just an epiphenomenon. The real modulating factor was the location of reaching target with respect to the point gazed by the animal, that is, the retinotopic coordinates towards which the action of reaching occurred. Comparison of neural discharge of the same cell during execution of foveated and non-foveated reaching movements, performed towards the same or different spatial locations, confirmed that in a part of V6A neurons reaching activity is coded retinocentrically. In other neurons, reaching activity is coded spatially, depending on the direction of reaching movement regardless of where the animal was looking at. The majority of V6A reaching neurons use a system that encompasses both of these reference frames. These results are in line with the view of a progressive visuomotor transformation in the dorsal visual stream, that changes the frame of reference from the retinocentric one, typically used by the visual system, to the arm-centred one, typically used by the motor system. PMID:18279330

Marzocchi, Nicoletta; Breveglieri, Rossella; Galletti, Claudio; Fattori, Patrizia

2008-02-01

427

Conceptual Model of Hydrologic and Thermal Conditions of the Eastbank Aquifer System near Rocky Reach Dam, Douglas County, Washington  

USGS Publications Warehouse

The Lower and Combined Aquifers of the Eastbank Aquifer system, located in a river-terrace deposit along the Columbia River near Rocky Reach Dam, Washington, are primarily recharged by the Columbia River and provide water to the Eastbank Hatchery and the regional water system servicing the cities of Wenatchee, East Wenatchee, and parts of unincorporated Chelan and Douglas Counties. In 2006, mean annual pumpage from the aquifers by the hatchery and regional water system was about 43 and 16 cubic feet per second, respectively. Reportedly, temperatures of ground water pumped by the hatchery have been increasing, thereby making water potentially too warm for salmonid fish production. An evaluation of hourly ground-water and river temperatures from January 1991 through August 2007 indicates increasing interannual trends in temperatures in most of the Lower and Combined Aquifers from 1999 through 2006 that correspond to increasing trends in the annual mean and annual maximum river temperatures during the same period of 0.07 and 0.17?C per year, respectively. There were no trends in the annual minimum river temperatures from 1999 through 2006, and there were no trends in the annual minimum, mean, and maximum river temperatures from 1991 through 1998 and from 1991 through 2007. Increases in river temperatures from 1999 through 2006 are within the natural variability of the river temperatures. Most of the Lower and Combined Aquifers reached thermal equilibrium?defined by constant time lags between changes in river temperatures and subsequent changes in ground-water temperatures?during 1991?98. The only exceptions are the Combined Aquifer north of the well field of the regional water system, which had not reached thermal equilibrium by 2006, and the Lower Aquifer west of the well fields of the hatchery and the regional water system, which reached thermal equilibrium prior to 1991. Because most of the Lower and Combined Aquifers were in thermal equilibrium from 1999 through 2006 and seasonal pumpage patterns were relatively stable, reported trends of increasing temperatures of water pumped by the hatchery well field are most likely explained by increasing trends in river temperatures. Most of the water pumped by the hatchery well field recharges in an area west to southwest of the well field about 2 months prior to the time it is pumped from the aquifer. The northern extent of the hatchery well field may pump some colder water from a bedrock depression to the north and west of the well field. The conceptual model of hydrologic and thermal conditions is supported by analyses of historical water temperatures, water-level data collected on July 18, 2007, and dissolved-constituent and bacterial concentrations in samples collected on August 20?22, 2007.

van Heeswijk, Marijke; Cox, Stephen E.; Huffman, Raegan L.; Curran, Christopher A.

2008-01-01

428

CORA: Emission Line Fitting with Maximum Likelihood  

NASA Astrophysics Data System (ADS)

The advent of pipeline-processed data both from space- and ground-based observatories often disposes of the need of full-fledged data reduction software with its associated steep learning curve. In many cases, a simple tool doing just one task, and doing it right, is all one wishes. In this spirit we introduce CORA, a line fitting tool based on the maximum likelihood technique, which has been developed for the analysis of emission line spectra with low count numbers and has successfully been used in several publications. CORA uses a rigorous application of Poisson statistics. From the assumption of Poissonian noise we derive the probability for a model of the emission line spectrum to represent the measured spectrum. The likelihood function is used as a criterion for optimizing the parameters of the theoretical spectrum and a fixed point equation is derived allowing an efficient way to obtain line fluxes. As an example we demonstrate the functionality of the program with an X-ray spectrum of Capella obtained with the Low Energy Transmission Grating Spectrometer (LETGS) on board the Chandra observatory and choose the analysis of the Ne IX triplet around 13.5 Å.

Ness, Jan-Uwe; Wichmann, Rainer

2011-12-01

429

CORA - emission line fitting with Maximum Likelihood  

NASA Astrophysics Data System (ADS)

The advent of pipeline-processed data both from space- and ground-based observatories often disposes of the need of full-fledged data reduction software with its associated steep learning curve. In many cases, a simple tool doing just one task, and doing it right, is all one wishes. In this spirit we introduce CORA, a line fitting tool based on the maximum likelihood technique, which has been developed for the analysis of emission line spectra with low count numbers and has successfully been used in several publications. CORA uses a rigorous application of Poisson statistics. From the assumption of Poissonian noise we derive the probability for a model of the emission line spectrum to represent the measured spectrum. The likelihood function is used as a criterion for optimizing the parameters of the theoretical spectrum and a fixed point equation is derived allowing an efficient way to obtain line fluxes. As an example we demonstrate the functionality of the program with an X-ray spectrum of Capella obtained with the Low Energy Transmission Grating Spectrometer (LETGS) on board the Chandra observatory and choose the analysis of the Ne IX triplet around 13.5 Å.

Ness, J.-U.; Wichmann, R.

2002-07-01

430

Finding maximum JPEG image block code size  

NASA Astrophysics Data System (ADS)

We present a study of JPEG baseline coding. It aims to determine the minimum storage needed to buffer the JPEG Huffman code bits of 8-bit image blocks. Since DC is coded separately, and the encoder represents each AC coefficient by a pair of run-length/AC coefficient level, the net problem is to perform an efficient search for the optimal run-level pair sequence. We formulate it as a two-dimensional, nonlinear, integer programming problem and solve it using a branch-and-bound based search method. We derive two types of constraints to prune the search space. The first one is given as an upper-bound for the sum of squares of AC coefficients of a block, and it is used to discard sequences that cannot represent valid DCT blocks. The second type constraints are based on some interesting properties of the Huffman code table, and these are used to prune sequences that cannot be part of optimal solutions. Our main result is that if the default JPEG compression setting is used, space of minimum of 346 bits and maximum of 433 bits is sufficient to buffer the AC code bits of 8-bit image blocks. Our implementation also pruned the search space extremely well; the first constraint reduced the initial search space of 4 nodes down to less than 2 nodes, and the second set of constraints reduced it further by 97.8%.

Lakhani, Gopal

2012-07-01

431

Penalized maximum likelihood for multivariate Gaussian mixture  

NASA Astrophysics Data System (ADS)

In this paper, we first consider the parameter estimation of a multivariate random process distribution using multivariate Gaussian mixture law. The labels of the mixture are allowed to have a general probability law which gives the possibility to modelize a temporal structure of the process under study. We generalize the case of univariate Gaussian mixture in [1] to show that the likelihood is unbounded and goes to infinity when one of the covariance matrices approaches the boundary of singularity of the non negative definite matrices set. We characterize the parameter set of these singularities. As a solution to this degeneracy problem, we show that the penalization of the likelihood by an Inverse Wishart prior on covariance matrices results to a penalized or maximum a posteriori criterion which is bounded. Then, the existence of positive definite matrices optimizing this criterion can be guaranteed. We also show that with a modified EM procedure or with a Bayesian sampling scheme, we can constrain covariance matrices to belong to a particular subclass of covariance matrices. Finally, we study degeneracies in the source separation problem where the characterization of parameter singularity set is more complex. We show, however, that Inverse Wishart prior on covariance matrices eliminates the degeneracies in this case too.

Snoussi, Hichem; Mohammad-Djafari, Ali

2002-05-01

432

Maximum likelihood inference of reticulate evolutionary histories.  

PubMed

Hybridization plays an important role in the evolution of certain groups of organisms, adaptation to their environments, and diversification of their genomes. The evolutionary histories of such groups are reticulate, and methods for reconstructing them are still in their infancy and have limited applicability. We present a maximum likelihood method for inferring reticulate evolutionary histories while accounting simultaneously for incomplete lineage sorting. Additionally, we propose methods for assessing confidence in the amount of reticulation and the topology of the inferred evolutionary history. Our method obtains accurate estimates of reticulate evolutionary histories on simulated datasets. Furthermore, our method provides support for a hypothesis of a reticulate evolutionary history inferred from a set of house mouse (Mus musculus) genomes. As evidence of hybridization in eukaryotic groups accumulates, it is essential to have methods that infer reticulate evolutionary histories. The work we present here allows for such inference and provides a significant step toward putting phylogenetic networks on par with phylogenetic trees as a model of capturing evolutionary relationships. PMID:25368173

Yu, Yun; Dong, Jianrong; Liu, Kevin J; Nakhleh, Luay

2014-11-18

433

Non-uniformly sampled Maximum Quantum spectroscopy.  

PubMed

Maximum-Quantum (MaxQ) NMR is an approach that exploits the simple lineshape (a singlet) of the highest possible coherence quantum order for a given spin system to help resolving the interpretation of the spectrum of complex mixtures. In this setup, resolution in the indirect, multiple-quantum, dimension is crucial, and it may be linked to a long duration of the signal acquired along this axis. We explored if this boundary on the length of the indirect dimension could not necessarily translate into extended experimental times by applying Non-Uniform Sampling (NUS) schemes in conjunction with Recursive Multi-Dimensional Decomposition (R-MDD) data processing. The actual value of the MaxQ order depends on the size of the spin system, so that for a mixture several MQ correlation spectra must be recorded to detect all possible molecular fragments. As the sparseness of the MQ datasets vary dramatically in going from higher (sparser) to lower (denser) coherence orders, the optimal compressing conditions and the fidelity of NUS/R-MDD scheme may vary along the series of MQ spectra. The NUS-MaxQ approach is demonstrated on the aromatic region of the 1H spectrum of a mixture of 10 simple aromatic molecules. PMID:21962930

Piotto, Martial; Reddy, G N Manjunatha; Caldarelli, Stefano

2011-12-01

434

Midnight Temperature Maximum Observations Over Millstone Hill  

NASA Astrophysics Data System (ADS)

The thermospheric Midnight Temperature Maximum (MTM) is a large-scale neutral temperature anomaly usually observed at low latitudes. The magnitude of temperature enhancements during low-latitude MTM events is about 50-150 K and its occurrence is linked to poleward surges in an otherwise "quiescent" equatorward meridional flow. The MTM is also associated with the post-midnight brightness of 630 nm (redline) emission and the downward descent of the F-region plasma (midnight collapse). Recent experimental and modeling studies have indicated that MTM anomalies extend into mid-latitudes, although observational evidence of the mid-latitude MTM in the literature is limited to a single site in the Southern Hemisphere. In this paper, we present observations of Northern Hemisphere mid-latitude MTM in Faby-Perot Interferometer (FPI) redline data from Millstone Hill Observatory (42.6° N, 71.49° W). The FPI at Millstone Hill has been operating since April, 2010 and providing F-region night-time neutral winds and temperatures. We present case studies of post-midnight red-line temperature enhancements and correlated poleward surges in the meridional neutral winds.; An example of Millstone Hill redline temperature and neutral wind measurements during an MTM event.

Azeem, S. I.; Crowley, G.; Noto, J.; Kerr, R. B.; Kapali, S.; Riccobono, J.; Migliozzi, M.

2012-12-01

435

Maximum life spiral bevel reduction design  

NASA Technical Reports Server (NTRS)

Optimization is applied to the design of a spiral bevel gear reduction for maximum life at a given size. 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 values. Gear tooth bending strength and minimum contact ratio under load are included in the active constraints. The optimal design of the spiral bevel gear reduction includes the selection of bearing and shaft proportions in addition to gear mesh parameters. System life is maximized subject to a fixed back-cone distance of the spiral bevel gear set for a specified speed ratio, shaft angle, input torque, and power. Significant parameters in the design are: the spiral angle, the pressure angle, the numbers of teeth on the pinion and gear, and the location and size of the four support bearings. Interpolated polynomials expand the discrete bearing properties and proportions into continuous variables for gradient optimization. After finding the continuous optimum, a designer can analyze near optimal designs for comparison and selection. Design examples show the influence of the bearing lives on the gear parameters in the optimal configurations. For a fixed back-cone distance, optimal designs with larger shaft angles have larger service lives.

Savage, M.; Prasanna, M. G.; Coe, H. H.

1992-01-01

436

How cold was the Last Glacial Maximum?  

NASA Astrophysics Data System (ADS)

Several collations of proxy data dating from the Last Glacial Maximum have been published, but they have rarely if ever been synthesised into a true global field or mean. While various arguments have previously been presented to the effect that the LGM mean temperature change was around -5C relative to pre-industrial, a recent analysis of Schmittner et al has rekindled interest in this question with a remarkably warm anomaly of -3C with a likely range of -2.1 to -3.3C, based on a model fit to the recent proxy collections of MARGO, Bartlein et al and Shakun et al. Here we present a number of analyses of essentially the same proxy data, based on methods ranging from purely statistical analyses to highly model-based fits. We use a number of cross-validation tests to evaluate the methods. We argue that the Schmittner et al analysis is likely too warm, and identify some possible explanation for this bias. While our analysis does not directly address the question of equilibrium climate sensitivity, some simple semi-quantitative reasoning suggests that this result of Schmittner et al may also be biased low. As well as a global mean temperature change, we present spatial fields that may be used for model testing and validation.

Annan, J. D.; Hargreaves, J. C.

2012-04-01

437

Lemniscate growth  

E-print Network

May 8, 2012 ... time), produced by a Laplacian growth process, is a family of ... We propose to call any such process governed by (2) “lemniscate growth” .... this case the level sets {z G(z) = t} move with velocity equal to ? times the ...... way, lemniscate growth might be viewed as a simplified model of a special case.

2012-05-08

438

PREHATCH AND POSTHATCH GROWTH OF FISHES-A GENERAL MODEL  

E-print Network

and yolk-sac growth curves reach asymptotic limits independent of temperature. Other biological events (ePREHATCH AND POSTHATCH GROWTH OF FISHES- A GENERAL MODEL JAMES R. ZWEIFEL AND REUBEN LASKER1 ABSTRACT The developmental stages of fish eggs and the growth of larval fishes of several species can

439

Rapid population growth.  

PubMed

At the current rate of population growth, world population by 2000 is expected to reach 7 billion or more, with developing countries accounting for some 5.4 billion, and economically advanced nations accounting for 1.6 billion. 'Population explosion' is the result of falling mortality rates and continuing high birth rates. Many European countries, and Japan, have already completed what is termed as demographic transition, that is, birth rates have fallen to below 20 births per 1000 population, death rates to 10/1000 population, and annual growth rates are 1% or less; annual growth rates for less developed countries ranged from 2 to 3.5%. Less developed countries can be divided into 3 groups: 1) countries with both high birth and death rates; 2) countries with high birth rates and low death rates; and 3) countries with intermediate and declining birth rates and low death rates. Rapid population growth has serious economic consequences. It encourages inequities in income distribution; it limits rate of growth of gross national product by holding down level of savings and capital investments; it exerts pressure on agricultural production and land; and it creates unemployment problems. In addition, the quality of education for increasing number of chidren is adversely affected, as high proportions of children reduce the amount that can be spent for the education of each child out of the educational budget; the cost and adequacy of health and welfare services are affected in a similar way. Other serious consequences of rapid population growth are maternal death and illness, and physical and mental retardation of children of very poor families. It is very urgent that over a billion births be prevented in the next 30 years to reduce annual population growth rate from the current 2% to 1% per year. PMID:12261450

1972-01-01

440

Locating Ground-Water Discharge in the Hanford Reach of the Columbia River  

SciTech Connect

A bottom-contacting probe for measuring electrical conductivity at the sediment-water interface was used to scan the bed of the Columbia River adjacent to the Hanford Site in southeast Washington State during a 10-day investigation. Four river-sections, each about a kilometer in length, were scanned for variations in electrical conductivity. The probe was towed along the riverbed at a speed of 1 m/s and is position was recorded using a Global Positioning System. The bottom tows revealed several areas of elevated electrical conductivity. Where these anomalies were relatively easy to access, piezometers were driven into the riverbed and porewater electrical conductivity ranged from 111 to 150 uS/cm. The piezometers, placed in electrical conductivity “hotspots,” yielded chemical or isotopic data consistent with previous analyses of water taken from monitoring wells and visible shoreline seeps. Tritium, nitrate, and chromium exceeded water quality standards in some porewaters. The highest tritium and nitrate levels were found near the Old Hanford Townsite at 120,000 pCi/L (+ 5,880 pCi/L total propagated analytical uncertainty) and ug/L (+ 5,880 ug/L), respectively. The maximum chromium (total and hexavalent) levels were found near 100-H reactor area where unfiltered porewater total chromium was 1,900 ug/L (+ 798 ug/L) and hexavalent chromium was 20 ug/L. The electrical conductivity probe provided rapid, cost-effective reconnaissance for ground-water discharge areas when used in combination with conventional piezometers. It may be possible to obtain quantitative estimates of both natural and contaminated ground-water discharge in the Hanford Reach with more extensive surveys of river bottom.

Lee, D.R.; Geist, D.R.; Saldi, K.; Hartwig, D.; Cooper, T.

1997-03-01

441

Estimate of Solar Maximum Using the 1-8 Å Geostationary Operational Environmental Satellites X-Ray Measurements  

NASA Astrophysics Data System (ADS)

We present an alternate method of determining the progression of the solar cycle through an analysis of the solar X-ray background. Our results are based on the NOAA Geostationary Operational Environmental Satellites (GOES) X-ray data in the 1-8 Å band from 1986 to the present, covering solar cycles 22, 23, and 24. The X-ray background level tracks the progression of the solar cycle through its maximum and minimum. Using the X-ray data, we can therefore make estimates of the solar cycle progression and the date of solar maximum. Based upon our analysis, we conclude that the Sun reached its hemisphere-averaged maximum in solar cycle 24 in late 2013. This is within six months of the NOAA prediction of a maximum in spring 2013.

Winter, L. M.; Balasubramaniam, K. S.

2014-10-01

442

Maximum Mouth Opening in Saudi Adolescents  

PubMed Central

Background: The aim of this study was to investigate the maximum mouth opening (MMO) in a representative sample of the Saudi adolescents. Materials and Methods: A total of 1825 Saudi adolescents (1007 males and 818 females) aged 12-16 years were randomly selected. The subjects were asked to open their mouth maximally till no further opening was possible and then the distance from the incisal edge of the maxillary incisors to incisal edge of the mandibular incisors was recorded. All data were analyzed using SPSS program and simple descriptive statistics of MMO with regard to gender and age groups were reported. The Student’s t-test and one-way analysis of variance were used to examine differences in mouth opening relative to gender and age groups. Results: The mean maximal mouth opening for males was 43.5 ± 4.23 mm (range 29-59 mm). The mean maximal mouth opening for females was 35.5 ± 4.4 mm (range 20-45 mm). There was a significant difference between the mouth opening of males and females in all the age group (P = 0.000). The mouth opening, regardless of gender, increases significantly with age from the age of 12 years to the age of 14 years (P = 0.000), then remained unchanged till the age of 16 years. Conclusion: The mouth opening of males is significantly higher than that of females in all the age group. There was a significant increase in MMO with age up to the age of 14 years regardless of gender.

Al-Dlaigan, Yousef H; Asiry, Moshabab A

2014-01-01

443

Reconstruction of the Early Mérida, pre-LGM glaciation with comparison to Late Glacial Maximum till, northwestern Venezuelan Andes  

NASA Astrophysics Data System (ADS)

Valley glaciers have been well studied in the northwestern Venezuelan Andes over the last 20-year period with most sourcing reconstructions limited to the Last Glacial Maximum (LGM) and confined to the mapping of moraine positions and the detailed analysis of pedostratigraphic sequences reaching back into the Middle Wisconsinan (Weichselian) Glaciation. Using bedding macrofeatures, fabric analysis (magnetic azimuths) with mirror images, clast inclination and microtextural evidence determined with the FE-SEM (Field Emission Scanning Electron Microscopy) and EDS (Energy Dispersive Spectroscopy), and micromorphology of the PED5 composite section of Early to Late Mérida age was analyzed to reconstruct the till succession and glacial dynamics. The fabric is used to reconstruct the build-up of valley ice in the lower Mucuñuque Valley, the icecap spreading over the upper catchments of neighbouring drainage basins toward the headwaters of the Mucuchache Valley over a time frame estimated to be < 90 ka and lasting to ˜ 60 ka. Microtextural analysis was invoked to determine if physical differences on quartz and garnet mineral surfaces could be determined between various diamictons such as subglacial, flow and meltout tills, and outwash. Sample identification was made optically and with EDS. The evidence supports the theory that a substantial ice mass - a virtual icecap - existed during the Early Mérida stade of the last glaciation with the ice mass originating and decaying from the upper Mucuñuque Catchment south over some 40° of arc. This is the first evidence for an icecap complex in the northwestern Andes. Comparison between Early and Late Mérida glacial styles indicates that, in the Mucuñuque-Mucuchache corridor of the Mérida Andes glaciation in the LGM was catchment restricted with no evidence of icecap growth.

Mahaney, William C.; Kalm, Volli; Menzies, John; Milner, Michael W.

2010-04-01

444

Freshwater discharges in a simulation of the Last Glacial Maximum climate using improved river routing  

NASA Astrophysics Data System (ADS)

The large ice-sheets over North America and Europe at the Last Glacial Maximum (LGM) strongly disturbed river pathways. This has never been taken into account in simulations of the LGM climate, even if it could have an impact on the freshwater input to the ocean. Here, we have introduced a more realistic river routing in LGM atmospheric general circulation model simulations. A comparison with classical LGM simulations shows that the discharge into the Arctic Ocean is not drastically different. Even if the Ob and Yenisei rivers could not reach the Arctic Ocean because of the Fennoscandian ice sheet (which results in a lake South of this ice sheet), the discharge of other rivers nearby is increased due to the influence of this lake. The maximum monthly discharge into the North Atlantic Ocean decreases by 34000 m3/s between 54 and 66°N, while it is stronger by 35000 m3/s between 28 and 54°N.

Alkama, R.; Kageyama, M.; Ramstein, G.

2006-11-01

445

49 CFR 230.27 - Maximum shearing strength of rivets.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Strength of Materials § 230.27 Maximum shearing strength of rivets. The maximum shearing strength of rivets per square...

2010-10-01

446

7 CFR 1738.18 - Minimum and maximum loan amount.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Minimum and maximum loan amount. 1738...and Basic Policies § 1738.18 Minimum and maximum loan amount. Recognizing plant costs, the applicant's cost of system design, and RUS'...

2010-01-01

447

7 CFR 1738.18 - Minimum and maximum loan amount.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Minimum and maximum loan amount. 1738...and Basic Policies § 1738.18 Minimum and maximum loan amount. Recognizing plant costs, the applicant's cost of system design, and RUS'...

2011-01-01

448

24 CFR 200.41 - Maximum mortgagee fees and charges.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Maximum mortgagee fees and charges. 200.41 Section 200.41 Housing...Requirements for Existing Projects Fees and Charges § 200.41 Maximum mortgagee fees and charges. (a) Mortgagee fees and...

2014-04-01

449

40 CFR 35.635 - Maximum federal share.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Maximum federal share. 35.635 Section 35.635 Protection of Environment ENVIRONMENTAL PROTECTION...Source Management Grants (sections 319(h) and 518(f)) § 35.635 Maximum federal share. (a) The...

2014-07-01

450

40 CFR 35.635 - Maximum federal share.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Maximum federal share. 35.635 Section 35.635 Protection of Environment ENVIRONMENTAL PROTECTION...Source Management Grants (sections 319(h) and 518(f)) § 35.635 Maximum federal share. (a) The...

2010-07-01

451

40 CFR 35.635 - Maximum federal share.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Maximum federal share. 35.635 Section 35.635 Protection of Environment ENVIRONMENTAL PROTECTION...Source Management Grants (sections 319(h) and 518(f)) § 35.635 Maximum federal share. (a) The...

2012-07-01

452

40 CFR 35.335 - Maximum federal share.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Maximum federal share. 35.335 Section 35.335 Protection of Environment ENVIRONMENTAL... State Underground Storage Tanks (section 2007(f)(2)) § 35.335 Maximum federal share. The Regional...

2010-07-01

453

40 CFR 35.335 - Maximum federal share.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Maximum federal share. 35.335 Section 35.335 Protection of Environment ENVIRONMENTAL... State Underground Storage Tanks (section 2007(f)(2)) § 35.335 Maximum federal share. The Regional...

2012-07-01

454

40 CFR 35.335 - Maximum federal share.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Maximum federal share. 35.335 Section 35.335 Protection of Environment ENVIRONMENTAL... State Underground Storage Tanks (section 2007(f)(2)) § 35.335 Maximum federal share. The Regional...

2013-07-01

455