Stability Characteristics of Two Missiles of Fineness Ratios 12 and 18 with Six Rectangular Fins of Very Low Aspect Ratio Over a Mach Number Range of 1.4 to 3.2

NASA Technical Reports Server (NTRS)

Henning, Allen B.

1959-01-01

Two rocket-propelled missiles have been test flown by the Langley Pilotless Aircraft Research Division in order to study the stability characteristics of a body with six rectangular fins of very low aspect ratio. The fins, which had exposed aspect ratios of approximately o.o4 and 0.02 per fin, were mounted on bodies of fineness ratios of 12 and 18, respectively. Each body had a nose with a fineness ratio of 3.5 and a cylindrical afterbody. The body and the fin chord of the model having a fineness ratio of 12 were extended the length of 6 body diameters to produce the model with a fineness ratio of 18. The missiles were disturbed in flight by pulse rockets in order to obtain the stability data. The tests were performed over a Mach number range of 1.4 to 3.2 and a Reynolds number range of 2 x 10(exp 6) to 21 x l0(exp 6). The results of these tests indicate that these configurations with the long rectangular fins of very low aspect ratio showed little induced roll" with the missile of highest fineness ratio and longest fin chord exhibiting the least amount. Extending the body and fin chord of the shorter missile six body diameters and thereby increasing the fin area approximately 115 percent increased the lift-curve slope based on body cross-sectional area approximately 40 to 55 percent, increased the dynamic stability by a substantial amount, and increased the drag from 14 to 33 percent throughout the comparable Mach number range. The center-of-pressure location of both missiles remained constant over the Mach number range.

Surrogate immiscible liquid pairs with refractive indexes matchable over a wide range of density and viscosity ratios

NASA Astrophysics Data System (ADS)

Saksena, Rajat; Christensen, Kenneth T.; Pearlstein, Arne J.

2015-08-01

In liquid-liquid flows, use of optical diagnostics is limited by interphase refractive index mismatch, which leads to optical distortion and complicates data interpretation, and sometimes also by opacity. Both problems can be eliminated using a surrogate pair of immiscible index-matched transparent liquids, whose density and viscosity ratios match corresponding ratios for the original liquid pair. We show that a wide range of density and viscosity ratios is accessible using aqueous solutions of 1,2-propanediol and CsBr (for which index, density, and viscosity are available), and solutions of light and heavy silicone oils and 1-bromooctane (for which we measured the same properties at 119 compositions). For each liquid phase, polynomials in the composition variables, least-squares fitted to index and density and to the logarithm of kinematic viscosity, were used to determine accessible density and viscosity ratios for each matchable index. Index-matched solution pairs can be prepared with density and viscosity ratios equal to those for water-liquid CO2 at 0 °C over a range of pressure (allowing water-liquid CO2 behavior at inconveniently high pressure to be simulated by 1-bar experiments), and for water-crude oil and water-trichloroethylene (avoiding opacity and toxicity problems, respectively), each over a range of temperature. For representative index-matched solutions, equilibration changes index, density, and viscosity only slightly, and mass spectrometry and elemental analysis show that no component of either phase has significant interphase solubility. Finally, procedures are described for iteratively reducing the residual index mismatch in surrogate solution pairs prepared on the basis of approximate polynomial fits to experimental data, and for systematically dealing with nonzero interphase solubility.

Impact of glyphosate-resistant corn, glyphosate applications and tillage on soil nutrient ratios, exoenzyme activities and nutrient acquisition ratios.

PubMed

Jenkins, Michael B; Locke, Martin A; Reddy, Krishna N; McChesney, Daniel S; Steinriede, R Wade

2017-01-01

We report results of the last two years of a 7 year field experiment designed to test the null hypothesis: applications of glyphosate on glyphosate-resistant (GR) and non-resistant (non-GR) corn (Zea mays L.) under conventional tillage and no-till would have no effect on soil exoenzymes and microbial activity. Bulk soil (BS) and rhizosphere soil (RS) macronutrient ratios were not affected by either GR or non-GR corn, or glyphosate applications. Differences observed between exoenzyme activities were associated with tillage rather than glyphosate applications. In 2013, nutrient acquisition ratios for bulk and rhizosphere soils indicated P limitations, but sufficient assimilable N. In 2014, P limitations were observed for bulk and rhizosphere soils, in contrast to balanced C and N acquisition ratios in rhizosphere soils. Stoichiometric relationships indicated few differences between glyphosate and non-glyphosate treatments. Negative correlations between C:P and N:P nutrient ratios and nutrient acquisition ratios underscored the inverse relation between soil nutrient status and microbial community exoenzyme activities. Inconsistent relationships between microbial community metabolic activity and exoenzyme activity indicated an ephemeral effect of glyphosate on BS exoenzyme activity. Except for ephemeral effects, glyphosate applications appeared not to affect the function of the BS and RS exoenzymes under conventional tillage or no-till. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Surrogate Immiscible Liquid Solution Pairs with Refractive Indexes Matchable Over a Wide Range of Density and Viscosity Ratios

NASA Astrophysics Data System (ADS)

Saksena, Rajat; Christensen, Kenneth T.; Pearlstein, Arne J.

2014-11-01

Use of laser diagnostics in liquid-liquid flows is limited by refractive index mismatch. This can be avoided using a surrogate pair of immiscible index-matched liquids, with density and viscosity ratios matching those of the original liquid pair. We demonstrate that a wide range of density and viscosity ratios is accessible using aqueous solutions of 1,2-propanediol and CsBr (for which index, density, and viscosity are available), and solutions of light and heavy silicone oils and 1-bromooctane (for which we measured the same properties at 119 compositions). For each liquid phase, polynomials in the composition variables were fitted to index and density and to the logarithm of kinematic viscosity, and the fits were used to determine accessible density and viscosity ratios for each matchable index. Index-matched solution pairs can be prepared with density and viscosity ratios equal to those for water-liquid CO2 at 0oC over a range of pressure, and for water-crude oil and water-trichloroethylene, each over a range of temperature. For representative index-matched solutions, equilibration changes index, density, and viscosity only slightly, and chemical analysis show that no component of either solution has significant interphase solubility. Partially supported by Intl. Inst. for Carbon-Neutral Energy Research.

Shoulder Dynamic Control Ratio and Rotation Range of Motion in Female Junior Elite Handball Players and Controls.

PubMed

van Cingel, Robert; Habets, Bas; Willemsen, Linn; Staal, Bart

2018-03-01

To compare glenohumeral range of motion and shoulder rotator muscle strength in healthy female junior elite handball players and controls. Cross-sectional case-control study. Sports medical center. Forty elite female handball players and 30 controls active in nonoverhead sports participated in this study. Passive external rotator (ER), internal rotator (IR), and total range of motion (TROM) of the dominant and nondominant arm were examined with a goniometer. An isokinetic dynamometer was used to evaluate concentric and eccentric rotator muscle strength at 60 and 120 degrees/s with dynamic control ratio (DCR = ERecc:IRcon) as the main outcome parameter. Except for the ER range of motion in the nondominant arm, no significant differences were found between groups for IR, ER of the dominant arm, and the TROM. Within the handball group, the side-to-side difference for IR of the dominant arm was -1.4 degrees. The ER and the TROM of the dominant arm were significantly larger, 6.3 and 4.9 degrees, respectively. For both groups, the DCR values were above 1 and no significant differences were found between the dominant and nondominant arm. The DCR values in the handball group were significantly lower than in the control group. Based on the adopted definitions for muscle imbalance, glenohumeral internal range of motion deficit and TROM deficit our elite female handball players seem not at risk for shoulder injuries. Prospective studies are needed to support the belief that a DCR below 1 places the shoulder at risk for injury.

Chemically active reduced graphene oxide with tunable C/O ratios.

PubMed

Compton, Owen C; Jain, Bonny; Dikin, Dmitriy A; Abouimrane, Ali; Amine, Khalil; Nguyen, Sonbinh T

2011-06-28

Organic dispersions of graphene oxide can be thermally reduced in polar organic solvents under reflux conditions to afford electrically conductive, chemically active reduced graphene oxide (CARGO) with tunable C/O ratios, dependent on the boiling point of the solvent. The reductions are achieved after only 1 h of reflux, and the corresponding C/O ratios do not change upon further thermal treatment. Hydroxyl and carboxyl groups can be removed when the reflux is carried out above 155 °C, while epoxides are removable only when the temperature is higher than 200 °C. The increasing hydrophobic nature of CARGO, as its C/O ratio increases, improves the dispersibility of the nanosheets in a polystyrene matrix, in contrast to the aggregates formed with CARGO having lower C/O ratios. The excellent processability of the obtained CARGO dispersions is demonstrated via free-standing CARGO papers that exhibit tunable electrical conductivity/chemical activity and can be used as lithium-ion battery anodes with enhanced Coulombic efficiency.

Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

NASA Astrophysics Data System (ADS)

Annewandter, Robert

2014-05-01

The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced gas transport and subsequent soil gas sampling during On-Site inspections. Generally, gas transport has been widely studied with different numerical codes. However, gas transport of radioxenons and radioiodines in the post-detonation regime and their possible fractionation is still neglected in the open peer-reviewed literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the multiple isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radionuclides, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different mass diffusivities due to mass differences between the radionuclides. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures or highly conductive faults which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a so-called ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which is recognized by the oil industry as leading in Discrete Fracture-Matrix (DFM) simulations. It has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations, fracture propagation in fractured, porous media, and Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic differential equations by a complementary finite

Vertical distributions of (99)Tc and the (99)Tc/(137)Cs activity ratio in the coastal water off Aomori, Japan.

PubMed

Nakanishi, Takahiro; Zheng, Jian; Aono, Tatsuo; Yamada, Masatoshi; Kusakabe, Masashi

2011-08-01

Using a sector-field ICP-MS the vertical distributions of the (99)Tc concentration and (99)Tc/(137)Cs activity ratio were measured in the coastal waters off Aomori Prefecture, Japan, where a spent-nuclear-fuel reprocessing plant has begun test operation. The (99)Tc concentrations in surface water ranged from 1.8 to 2.4 mBq/m(3), no greater than the estimated background level. Relatively high (99)Tc/(137)Cs activity ratios (10-12 × 10(-4)) would be caused by the inflow of the high-(99)Tc/(137)Cs water mass from the Japan Sea. There is no observable contamination from the reprocessing plant in the investigated area. The (99)Tc concentration and the (99)Tc/(137)Cs activity ratio in water column showed gradual decreases with depth. Our results implied that (99)Tc behaves in a more conservative manner than (137)Cs in marine environments. Copyright © 2011 Elsevier Ltd. All rights reserved.

High-precision determination of {sup 234}U/{sup 238}U activity ratios in natural waters and carbonates by ICPMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ketterer, M.E.; Khourey, C.J.

1998-12-31

A method has been developed for precise measurement of {sup 234}U/{sup 238}U activity ratios in natural waters and carbonates using quadrupole inductively coupled plasma mass spectrometry. A recovery of 80--85% of seawater U is achieved by Fe(III) coprecipitation followed by extraction chromatography with a supported dipentyl pentane phosphonate material; 90--95% of U is recovered from carbonates, which are dissolved in HNO{sub 3} and subjected to the same extraction chromatographic preparation. Isotopic measurements are made via recirculating pneumatic nebulization of small volumes of solutions containing 0.5--5 mg/L U. {sup 234}U/{sup 235}U is measured as a proxy for determination of {sup 234}U/{supmore » 238}U; iridium is added to sample solutions and the ion ratio {sup 191}Ir{sup 40}Ar{sup +}/{sup 193}Ir{sup 40}Ar{sup +} is measured for internal mass discrimination correction {sup 234}U/{sup 238}U activity ratios in the range 1.143--1.154 are observed for 13 seawater and contemporary corals, in agreement with the established marine {sup 234}U/{sup 238}U activity ratio. For samples sizes of 5--25 {micro}g U, ICPMS uncertainties of {+-} 0.2--0.5% relative, 2{theta} standard error, approach those obtained for < 0.1 {micro}g U by thermal ionization mass spectrometry. Measurements of {sup 234}U/{sup 238}U activity ratios in bottled waters, Lake Erie surface waters, mollusk fossils, and fertilizers are also demonstrated.« less

Diagnostic reference range of κ/λ free light chain ratio to screen for Bence Jones proteinuria is not significantly influenced by GFR.

PubMed

Schmidt-Hieltjes, Yvonne; Elshof, Clemens; Roovers, Lian; Ruinemans-Koerts, Janneke

2016-05-01

The aim of our study was to analyse whether the κ/λ free light chain ratio reference range for screening for Bence Jones proteinuria should be dependent on the estimated glomerular filtration rate (eGFR). The serum κ/λ free light chain ratio, eGFR, serum M-protein and Bence Jones protein were measured in 544 patients for whom Bence Jones protein analysis was ordered. In the population of patients without Bence Jones proteinuria or a M-protein (n = 402), there is no gradual increase in κ/λ free light chain ratio with diminishing eGFR. The κ/λ free light chain ratio in this group was 0.56-1.86 (95% interval). With this diagnostic reference range of the κ/λ ratio, 105 of the 110 patients with Bence Jones protein could be identified correctly. Only five patients with Bence Jones proteinuria (<0.17 g/L) were missed, without diagnostic or therapeutic consequences. In 36 patients (6.6%), an abnormal κ/λ free light chain ratio was measured without the presence of Bence Jones proteinuria. A κ/λ free light chain ratio in serum can be used safely and efficiently to select urine samples which should be analysed for Bence Jones proteinuria with an electrophoresis/immunofixation technique. Using this diagnostic reference range, the number of urine samples which should be analysed by electrophoresis/immunofixation could be reduced by 74%. The diagnostic reference interval can be determined best in a group of patients for whom Bence Jones analysis is indicated. For calculation of this reference range, the eGFR value does not need to be taken into account. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Hydrothermal synthesis and enhanced photocatalytic activity of mixed-phase TiO2 powders with controllable anatase/rutile ratio

NASA Astrophysics Data System (ADS)

Wang, Qi; Qiao, Zhi; Jiang, Peng; Kuang, Jianlei; Liu, Wenxiu; Cao, Wenbin

2018-03-01

In this study, mixed-phase TiO2 powders were novelly synthesized via a facile and mild hydrothermal method without any post-heat treatment. TiOSO4 and peroxide titanic acid (PTA) were used as inorganic titanium sources, while no special solvent or additive were introduced. The XRD and TEM results showed the mixed-phase TiO2 powders were composed of anatase and rutile phases, and the PTA sol played an important role on forming the rutile nucleus. The proportion of rutile in the mixed-phase TiO2 could be easily controlled in the range of 0%-70.5% by changing the amount of PTA sol used in the synthesis process. The UV-Visible absorption spectra indicated the prepared mixed-phase TiO2 showed enhanced visible light absorption with the increase of rutile ratio. The photodegradation experiments revealed the mixed-phase TiO2 exhibited the best photocatalytic activity at the rutile ratio of 41.5%, while a higher or lower rutile ratio both resulted in the decrease of photocatalytic activity.

Classifying organic materials by oxygen-to-carbon elemental ratio to predict the activation regime of cloud condensation nuclei (CCN)

NASA Astrophysics Data System (ADS)

Kuwata, M.; Shao, W.; Lebouteiller, R.; Martin, S. T.

2012-12-01

The governing highly soluble, slightly soluble, or insoluble activation regime of organic compounds as cloud condensation nuclei (CCN) was examined as a function of oxygen-to-carbon elemental ratio (O : C). New data were collected for adipic, pimelic, suberic, azelaic and pinonic acids. Secondary organic materials (SOMs) produced by α-pinene ozonolysis and isoprene photo-oxidation were also included in the analysis. The saturation concentrations C of the organic compounds in aqueous solutions served as the key parameter for delineating regimes of CCN activation, and the values of C were tightly correlated to the O : C ratios. The highly soluble, slightly soluble, and insoluble regimes of CCN activation were found to correspond to ranges of [O : C] > 0.6, 0.2 < [O : C] < 0.6, and [O : C] < 0.2, respectively. These classifications were evaluated against CCN activation data of isoprene-derived SOM (O : C = 0.69-0.72) and α-pinene-derived SOM (O : C = 0.38-0.48). Isoprene-derived SOM had highly soluble activation behavior, consistent with its high O : C ratio. For α-pinene-derived SOM, although CCN activation can be modeled as a highly soluble mechanism, this behavior was not predicted by the O : C ratio, for which a slightly soluble mechanism was anticipated. Complexity in chemical composition, resulting in continuous water uptake and the absence of a deliquescence transition that can thermodynamically limit CCN activation, might explain the differences of α-pinene-derived SOM compared to the behavior of pure organic compounds. The present results suggest that atmospheric particles dominated by hydrocarbon-like organic components do not activate (i.e. insoluble regime) whereas those dominated by oxygenated organic components activate (i.e. highly soluble regime).

Classifying organic materials by oxygen-to-carbon elemental ratio to predict the activation regime of Cloud Condensation Nuclei (CCN)

NASA Astrophysics Data System (ADS)

Kuwata, M.; Shao, W.; Lebouteiller, R.; Martin, S. T.

2013-05-01

The governing highly soluble, slightly soluble, or insoluble activation regime of organic compounds as cloud condensation nuclei (CCN) was examined as a function of oxygen-to-carbon elemental ratio (O : C). New data were collected for adipic, pimelic, suberic, azelaic, and pinonic acids. Secondary organic materials (SOMs) produced by α-pinene ozonolysis and isoprene photo-oxidation were also included in the analysis. The saturation concentrations C of the organic compounds in aqueous solutions served as the key parameter for delineating regimes of CCN activation, and the values of C were tightly correlated to the O : C ratios. The highly soluble, slightly soluble, and insoluble regimes of CCN activation were found to correspond to ranges of [O : C] > 0.6, 0.2 < [O : C] < 0.6, and [O : C] < 0.2, respectively. These classifications were evaluated against CCN activation data of isoprene-derived SOM (O : C = 0.69-0.72) and α-pinene-derived SOM (O : C = 0.38-0.48). Isoprene-derived SOM had highly soluble activation behavior, consistent with its high O : C ratio. For α-pinene-derived SOM, although CCN activation can be modeled as a highly soluble mechanism, this behavior was not predicted by the O : C ratio, for which a slightly soluble mechanism was anticipated. Complexity in chemical composition, resulting in continuous water uptake and the absence of a deliquescence transition that can thermodynamically limit CCN activation, might explain the difference in the behavior of α-pinene-derived SOM compared to that of pure organic compounds. The present results suggest that atmospheric particles dominated by hydrocarbon-like organic components do not activate (i.e., insoluble regime) whereas those dominated by oxygenated organic components activate (i.e., highly soluble regime) for typical atmospheric cloud life cycles.

Short-range correlations control the G/K and Poisson ratios of amorphous solids and metallic glasses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zaccone, Alessio; Terentjev, Eugene M.

2014-01-21

The bulk modulus of many amorphous materials, such as metallic glasses, behaves nearly in agreement with the assumption of affine deformation, namely that the atoms are displaced just by the amount prescribed by the applied strain. In contrast, the shear modulus behaves as for nonaffine deformations, with additional displacements due to the structural disorder which induce a marked material softening to shear. The consequence is an anomalously large ratio of the bulk modulus to the shear modulus for disordered materials characterized by dense atomic packing, but not for random networks with point atoms. We explain this phenomenon with a microscopicmore » derivation of the elastic moduli of amorphous solids accounting for the interplay of nonaffinity and short-range particle correlations due to excluded volume. Short-range order is responsible for a reduction of the nonaffinity which is much stronger under compression, where the geometric coupling between nonaffinity and the deformation field is strong, whilst under shear this coupling is weak. Predictions of the Poisson ratio based on this model allow us to rationalize the trends as a function of coordination and atomic packing observed with many amorphous materials.« less

Species–genus ratios reflect a global history of diversification and range expansion in marine bivalves

PubMed Central

Krug, Andrew Z; Jablonski, David; Valentine, James W

2008-01-01

The distribution of marine bivalve species among genera and higher taxa takes the form of the classic hollow curve, wherein few lineages are species rich and many are species poor. The distribution of species among genera (S/G ratio) varies with latitude, with temperate S/G's falling within the null expectation, and tropical and polar S/G's exceeding it. Here, we test several hypotheses for this polar overdominance in the species richness of small numbers of genera. We find a significant positive correlation between the latitudinal range of a genus and its species richness, both globally and within regions. Genus age and species richness are also positively related, but this relationship breaks down when the analysis is limited to genera endemic to climate zones or with narrow latitudinal ranges. The data suggest a link between speciation and range-expansion, with genera expanding out of the tropical latitudinal bins tending to speciate more prolifically, both globally and regionally. These genera contain more species within climate zones than taxa endemic to that zone. Range expansion thus appears to be fundamentally coupled with speciation, producing the skewed distribution of species among genera, both globally and regionally, whereas clade longevity is achieved through extinction—resistance conferred by broad geographical ranges. PMID:18270156

[Hydrogen production and enzyme activity of acidophilic strain X-29 at different C/N ratio].

PubMed

Li, Qiu-bo; Xing, De-feng; Ren, Nan-qi; Zhao, Li-hua; Song, Ye-ying

2006-04-01

Some fermentative bacteria can produce hydrogen by utilizing carbohydrate and other kinds of organic compounds as substrates. Hydrogen production was also determined by both the limiting of growth and related enzyme activity in energy metabolism. Carbon and nitrogen are needed for the growth and metabolism of microorganisms. In addition, the carbon/nitrogen (C/N) ratio can influence the material metabolized and the energy produced. In order to improve the hydrogen production efficiency of the bacteria, we analyzed the effect of different C/N ratios on hydrogen production and the related enzyme activities in the acidophilic strain X-29 using batch test. The results indicate that the differences in the metabolism level and enzyme activity are obvious at different C/N ratios. Although the difference in liquid fermentative products produced per unit of biomass is not obvious, hydrogen production is enhanced at a specifically determined ratio. At a C/N ratio of 14 the accumulative hydrogen yield of strain X-29 reaches the maximum, 2210.9 mL/g. At different C/N ratios, the expression of hydrogenase activity vary; the activity of hydrogenase decrease quickly after reaching a maximum along with the fermentation process, but the time of expression is short. The activity of alcohol dehydrogenase (ADH) tend to stabilize after reaching a peak along with the fermentation process, the difference in expression activity is little, and the expression period is long at different C/N ratios. At a C/N ratio of 14 hydrogenase and ADH reach the maximum 2.88 micromol x (min x mg)(-1) and 33.2 micromol x (min x mg)(-1), respectively. It is shown that the C/N ratio has an important effect on enhancing hydrogen production and enzyme activity.

Upper body push and pull strength ratio in recreationally active adults.

PubMed

Negrete, Rodney J; Hanney, William J; Pabian, Patrick; Kolber, Morey J

2013-04-01

Agonist to antagonist strength data is commonly analyzed due to its association with injury and performance. The purpose of this study was to examine the agonist to antagonist ratio of upper body strength using two simple field tests (timed push up/timed modified pull up) in recreationally active adults and to establish the basis for reference standards. One hundred eighty (180) healthy recreationally active adults (111 females and 69 males, aged 18-45 years) performed two tests of upper body strength in random order: 1. Push-ups completed during 3 sets of 15 seconds with a 45 second rest period between each set and 2. Modified pull-ups completed during 3 sets of 15 seconds with a 45 second rest period between each set. The push-up to modified pull-up ratio for the males was 1.57:1, whereas females demonstrated a ratio of 2.72:1. The results suggest that for our group of healthy recreationally active subjects, the upper body "pushing" musculature is approximately 1.5-2.7 times stronger than the musculature involved for pulling. In this study, these recreationally active adults displayed greater strength during the timed push-ups than the modified pull-ups. The relationship of these imbalances to one's performance and or injury risk requires further investigation. The reference values, however, may serve the basis for future comparison and prospective investigations. The field tests in this study can be easily implemented by clinicians and an agonist/antagonist ratio can be determined and compared to our findings. 2b.

Low plasma renin activity and high aldosterone/renin ratio are associated with untreated isolated systolic hypertension.

PubMed

Durukan, Mine; Guray, Umit; Aksu, Tolga; Guray, Yesim; Demirkan, Burcu; Korkmaz, Sule

2012-10-01

Isolated systolic hypertension (ISH) is generally encountered in elderly patients and there are scarce data regarding the renin-angiotensin-aldosterone system (RAAS) activity in patients with ISH. We aimed to determine the plasma renin activity (PRA), plasma aldosterone levels (PAL) and aldosterone/PRA ratio (PAL/PRA) in patients (age >50 years) with ISH and to compare these values with patients with essential hypertension (EH) as well as subjects with normal blood pressure values (control) who have similar age and cardiovascular risk profile. Consecutively, 42 untreated ISH patients, 30 patients with EH and 29 normal subjects were included in the study. Parameters were presented as median (interquartile range). There were no significant differences regarding age, gender and other cardiovascular risk factors among groups. As expected, systolic, diastolic blood pressure and pulse pressure values were significantly different among groups. Besides, PRA values were found to be significantly lower in patients with ISH (0.4 [0.2-1.1] ng/ml/h) compared with the EH (0.95 [0.5-2.6] ng/ml/h, p =0.024) and control (1.3 [0.7-2.1] ng/ml/h, p =0.001) groups. Although, PAL were similar among groups, PAL/PRA ratio was significantly higher in ISH group (134.1 [73-224]) compared with those with EH (42.2 [35-84], p <0.001) and the control group (53.3 [30-106], p =0.001). No significant difference was present with respect to PAL/PRA ratio between EH and control groups. Our findings suggested that in patients with ISH, despite lower PRA levels, PAL/PRA ratio is significantly higher compared with the patients with EH and subjects with normal blood pressure. Since higher PAL/PRA levels is an indicator of relative aldosterone excess, medications blocking RAAS activity including aldosterone antagonists may have useful cardiovascular consequences in addition to their antihypertensive effects in ISH.

Dispersal, niche breadth and population extinction: colonization ratios predict range size in North American dragonflies.

PubMed

McCauley, Shannon J; Davis, Christopher J; Werner, Earl E; Robeson, Michael S

2014-07-01

negative relationship between North American range size and species' extinction-to-colonization ratios. Our results indicate that metapopulation dynamics act to shape the extent of species' continental distributions. These population dynamics are likely to interact with dispersal behaviour, particularly at species range margins, to determine range limits and ultimately species range sizes. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Temporal Variations in 234U/238U Activity Ratios in the Lower Mississippi River due to Changes in Source Tributary Discharges

NASA Astrophysics Data System (ADS)

Grzymko, T. J.; Marcantonio, F.; McKee, B. A.; Stewart, C. M.

2004-12-01

The world's 25 largest river systems contribute nearly 50% of all freshwater to the global ocean and carry large quantities of dissolved trace metals annually. Trace metal concentrations in these systems show large variances on seasonal time scales. In order to constrain the causes of these variations, consistent sampling on sub-seasonal time intervals is essential. Here, we focus on the Mississippi River, the seventh largest river in the world in terms of freshwater discharge and the third largest in terms of drainage basin area. Biweekly sampling of the lower Mississippi River at New Orleans was performed from January 2003 to August 2004. Uranium concentrations and 234U/238U activity ratios were measured for the dissolved component (<0.2 μ m-fraction) of river water. Over the course of this study, dissolved U activity ratios spanned a range of about 25%, from 1.23 to 1.60. Dissolved U concentrations ranged from 0.28 to 1.06 ppb. The relationship between concentrations, activity ratios, and lower river discharge is complicated, and no clear pattern is observed on both biweekly and seasonal timescales. However, there does seem to be a relationship between the larger seasonal trends in the lower Mississippi River and variations in the discharge of its upstream tributaries. To constrain this relationship, we have sampled water from the Missouri River, the upper Mississippi River above the confluence with the Missouri, the Ohio River, and the Arkansas River in February, April, and August of 2004. For the upstream samples measured thus far, the highest dissolved uranium concentrations are observed for the Missouri River at 2.02 ppb, while the lowest are found in the Ohio River at 0.38 ppb. Dissolved 234U/238U activity ratios are as unique for each tributary and vary from 1.36 in the Ohio River to 1.51 in the Missouri River. A preliminary mass balance analysis reveals that the lower river uranium activity ratios are controlled simply by the quantity and isotope

Differences in the activation and co-activation ratios of the four subdivisions of trapezius between genders following a computer typing task.

PubMed

Szucs, Kimberly A; Molnar, Megan

2017-04-01

The aim of this study was to provide a description of gender differences of the activation patterns of the four subdivisions of the trapezius (clavicular, upper, middle, lower) following a 60min computer work task. Surface EMG was collected from these subdivisions from 21 healthy subjects during bilateral arm elevation pre-/post- task. Subjects completed a standardized 60min computer work task at a standard, ergonomic workstation. Normalized activation and activation ratios of each trapezius subdivision were compared between genders and condition with repeated measures ANOVAs. The interaction effect of Gender×Condition for upper trapezius% activation approached significance at p=0.051with males demonstrating greater activation post-task. The main effect of Condition was statistically significant for% activation of middle and lower trapezius (p<0.05), with both muscles demonstrating increase activation post-task. There was a statistically significant interaction effect of Gender×Condition for the Middle Trapezius/Upper Trapezius ratio and main effect of Condition for the Clavicular Trapezius/Upper Trapezius ratio, with a decreased ratio post-typing. Gender differences exist following 60min of a low force computer typing task. Imbalances in muscle activation and activation ratios following computer work may affect total shoulder kinematics and should be further explored. Copyright © 2017 Elsevier B.V. All rights reserved.

UPPER BODY PUSH AND PULL STRENGTH RATIO IN RECREATIONALLY ACTIVE ADULTS

PubMed Central

Hanney, William J.; Pabian, Patrick; Kolber, Morey J.

2013-01-01

Introduction: Agonist to antagonist strength data is commonly analyzed due to its association with injury and performance. The purpose of this study was to examine the agonist to antagonist ratio of upper body strength using two simple field tests (timed push up/timed modified pull up) in recreationally active adults and to establish the basis for reference standards. Methods: One hundred eighty (180) healthy recreationally active adults (111 females and 69 males, aged 18‐45 years) performed two tests of upper body strength in random order: 1. Push‐ups completed during 3 sets of 15 seconds with a 45 second rest period between each set and 2. Modified pull‐ups completed during 3 sets of 15 seconds with a 45 second rest period between each set. Results: The push‐up to modified pull‐up ratio for the males was 1.57:1, whereas females demonstrated a ratio of 2.72:1. The results suggest that for our group of healthy recreationally active subjects, the upper body “pushing” musculature is approximately 1.5–2.7 times stronger than the musculature involved for pulling. Conclusions: In this study, these recreationally active adults displayed greater strength during the timed push‐ups than the modified pull‐ups. The relationship of these imbalances to one's performance and or injury risk requires further investigation. The reference values, however, may serve the basis for future comparison and prospective investigations. The field tests in this study can be easily implemented by clinicians and an agonist/antagonist ratio can be determined and compared to our findings. Level of Evidence: 2b PMID:23593552

Fast range estimation based on active range-gated imaging for coastal surveillance

NASA Astrophysics Data System (ADS)

Kong, Qingshan; Cao, Yinan; Wang, Xinwei; Tong, Youwan; Zhou, Yan; Liu, Yuliang

2012-11-01

Coastal surveillance is very important because it is useful for search and rescue, illegal immigration, or harbor security and so on. Furthermore, range estimation is critical for precisely detecting the target. Range-gated laser imaging sensor is suitable for high accuracy range especially in night and no moonlight. Generally, before detecting the target, it is necessary to change delay time till the target is captured. There are two operating mode for range-gated imaging sensor, one is passive imaging mode, and the other is gate viewing mode. Firstly, the sensor is passive mode, only capturing scenes by ICCD, once the object appears in the range of monitoring area, we can obtain the course range of the target according to the imaging geometry/projecting transform. Then, the sensor is gate viewing mode, applying micro second laser pulses and sensor gate width, we can get the range of targets by at least two continuous images with trapezoid-shaped range intensity profile. This technique enables super-resolution depth mapping with a reduction of imaging data processing. Based on the first step, we can calculate the rough value and quickly fix delay time which the target is detected. This technique has overcome the depth resolution limitation for 3D active imaging and enables super-resolution depth mapping with a reduction of imaging data processing. By the two steps, we can quickly obtain the distance between the object and sensor.

Temporal Variations in 234U/238U Activity Ratios in Four Mississippi River Tributaries

NASA Astrophysics Data System (ADS)

Grzymko, T. J.; Marcantonio, F.

2005-05-01

In 2004 we sampled the four tributaries that are the major contributors to the Mississippi River in terms of water discharge, i.e., the Arkansas, Missouri, Upper Mississippi, and Ohio rivers. Each river was sampled four times over the course of the year at variable levels of discharge in an attempt to constrain the causes of the temporal variations of 234U/238U activity ratios in the lower Mississippi River at New Orleans. The tributary uranium data support the idea that lower river uranium isotope and elemental systematics are controlled by a simple mass balance of the source tributary discharges. Furthermore, the uranium isotope ratios of the individual tributaries show coherent patterns of variability. Specifically, the data obtained from the four sampling trips yielded similar patterns of temporal variation in the 234U/238U activity ratios of all of the rivers, although the absolute values of these ratios were distinctly different from one river to the next. The pattern was such that the highest 234U/238U activity ratios were observed during the highest flow associated with the spring freshet while the lowest ratios occurred during the summer. For example, in the Missouri River, the 234U/238U activity ratios varied from 1.51 (February 12) to 1.37 (April 14) to 1.34 (July 16) to 1.37 (November 12), while in the Ohio River the same ratios varied from 1.36 (February 12) to 1.29 (April 14) to 1.21 (July 16) to 1.23 (November 12). The apparent seasonal pattern of these ratios in each tributary has led to several ideas as to the causes of the observed trends. The first, and most obvious, is that in each individual drainage basin there are various source tributaries that contribute to the uranium isotope systematics of the main stem of the tributary of interest. It follows that the variations in the uranium activity ratios may be caused by spatial variations in the source rock chemistry of the drainage basin. Other more complex scenarios can also be envisioned and

Transition temperature range of thermally activated nickel-titanium archwires

PubMed Central

SPINI, Tatiana Sobottka; VALARELLI, Fabrício Pinelli; CANÇADO, Rodrigo Hermont; de FREITAS, Karina Maria Salvatore; VILLARINHO, Denis Jardim

2014-01-01

Objectives The shape memory resulting from the superelasticity and thermoelastic effect is the main characteristic of thermally activated NiTi archwires and is closely related to the transition temperature range (TTR). The aim of this study was to evaluate the TTR of thermally activated NiTi archwires commercially available. Material and Methods Seven different brands of 0.019"x0.025" thermally activated nickel-titanium archwires were tested as received by differential scanning calorimetry (DSC) over the temperature range from -100°C to 150°C at 10°C/min. Results All thermally activated NiTi archwires analyzed presented stage transformation during thermal scanning with final austenitic temperature (Af) ranging from 20.39°C to 45.42°C. Three brands of NiTi archwires presented Af close to the room temperature and, this way, do not present properties of shape memory and pseudoelasticity that are desirable in clinical applications. Conclusions The thermally activated NiTi archwires present great variability in the TTR and the elastic parameters of each NiTi archwire should be provided by the manufacturers, to allow achievement of the best clinical performance possible. PMID:24676581

Long-range forces affecting equilibrium inertial focusing behavior in straight high aspect ratio microfluidic channels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reece, Amy E.; Oakey, John, E-mail: joakey@uwyo.edu

2016-04-15

The controlled and directed focusing of particles within flowing fluids is a problem of fundamental and technological significance. Microfluidic inertial focusing provides passive and precise lateral and longitudinal alignment of small particles without the need for external actuation or sheath fluid. The benefits of inertial focusing have quickly enabled the development of miniaturized flow cytometers, size-selective sorting devices, and other high-throughput particle screening tools. Straight channel inertial focusing device design requires knowledge of fluid properties and particle-channel size ratio. Equilibrium behavior of inertially focused particles has been extensively characterized and the constitutive phenomena described by scaling relationships for straight channelsmore » of square and rectangular cross section. In concentrated particle suspensions, however, long-range hydrodynamic repulsions give rise to complex particle ordering that, while interesting and potentially useful, can also dramatically diminish the technique’s effectiveness for high-throughput particle handling applications. We have empirically investigated particle focusing behavior within channels of increasing aspect ratio and have identified three scaling regimes that produce varying degrees of geometrical ordering between focused particles. To explore the limits of inertial particle focusing and identify the origins of these long-range interparticle forces, we have explored equilibrium focusing behavior as a function of channel geometry and particle concentration. Experimental results for highly concentrated particle solutions identify equilibrium thresholds for focusing that scale weakly with concentration and strongly with channel geometry. Balancing geometry mediated inertial forces with estimates for interparticle repulsive forces now provide a complete picture of pattern formation among concentrated inertially focused particles and enhance our understanding of the fundamental

Pulsed activation measurement of the Doppler effect of uranium-238 over the temperature range 300 to 3115 K

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharyya, S.K.; Russell, G.J.; Foell, W.K.

The Doppler effect for /sup 235/U-enriched UO/sub 2/ fuel pellets has been measured by the Pulsed Activation Doppler (PAD) technique in a TRIGA reactor. A combination of static electrical preheating and pulsed fission heating during irradiation was used to perform the measurements at temperatures extending from 300 K to the melting point of UO/sub 2/ (3115 K). The /sup 235/U enrichment in the experimental samples investigated ranged from 0.22 to 12 percent by weight. Measurements were made at under partially molten conditions of UO/sub 2/. Two sizes of pellets were used, with nominal surface-to-mass ratio values of 0.63 and 1.08more » cm/sup 2//g, respectively. The experimentally determined values of the Doppler ratio were in good agreement with resonance integral ratios determined from GAROL calculations and extrapolations of the low-temperature Hellstrand correlation.« less

Feasible Muscle Activation Ranges Based on Inverse Dynamics Analyses of Human Walking

PubMed Central

Simpson, Cole S.; Sohn, M. Hongchul; Allen, Jessica L.; Ting, Lena H.

2015-01-01

Although it is possible to produce the same movement using an infinite number of different muscle activation patterns owing to musculoskeletal redundancy, the degree to which observed variations in muscle activity can deviate from optimal solutions computed from biomechanical models is not known. Here, we examined the range of biomechanically permitted activation levels in individual muscles during human walking using a detailed musculoskeletal model and experimentally-measured kinetics and kinematics. Feasible muscle activation ranges define the minimum and maximum possible level of each muscle’s activation that satisfy inverse dynamics joint torques assuming that all other muscles can vary their activation as needed. During walking, 73% of the muscles had feasible muscle activation ranges that were greater than 95% of the total muscle activation range over more than 95% of the gait cycle, indicating that, individually, most muscles could be fully active or fully inactive while still satisfying inverse dynamics joint torques. Moreover, the shapes of the feasible muscle activation ranges did not resemble previously-reported muscle activation patterns nor optimal solutions, i.e. static optimization and computed muscle control, that are based on the same biomechanical constraints. Our results demonstrate that joint torque requirements from standard inverse dynamics calculations are insufficient to define the activation of individual muscles during walking in healthy individuals. Identifying feasible muscle activation ranges may be an effective way to evaluate the impact of additional biomechanical and/or neural constraints on possible versus actual muscle activity in both normal and impaired movements. PMID:26300401

Range degradation and distal edge behavior of proton radiotherapy beams using 11C activation and Monte Carlo simulation

NASA Astrophysics Data System (ADS)

Elmekawy, Ahmed Farouk

The distal edge of therapeutic proton radiation beams was investigated by different methods. Proton beams produced at the Hampton University Proton Therapy Institute (HUPTI) were used to irradiate a Polymethylmethacrylate (PMMA) phantom for three different ranges (13.5, 17.0 and 21.0 cm) to investigate the distal slope dependence of the Bragg peak. The activation of 11 C was studied by scanning the phantom less than 10 minutes post-irradiation with a Philips Big Bore Gemini(c) PET/CT. The DICOM images were imported into the Varian Eclipse(c) Treatment Planning System (TPS) for analysis and then analyzed by ImageJ(c) . The distal slope ranged from ?0.1671 +/- 0.0036 to -0.1986 +/- 0.0052 (pixel intensity/slice number) for ranges 13.5 to 21.0 cm respectively. A realistic description of the setup was modeled using the GATE 7.0 Monte Carlo simulation tool and compared to the experiment data. The results show the distal slope ranged from -0.1158+/-0.0133 to -0.0787+/-0.002 (Gy/mm). Additionally, low activity, 11C were simulated to study the 11C reconstructed half-life dependence versus the initial activity for six ranges chosen around the previous activation study. The results of the expected/nominal half-life vs. activity ranged from -5 x 10-4 +/- 2.8104 x 10-4 to 1.6 x 10-3 +/- 9.44 x 10-4 (%diff./Bq). The comparison between two experiments with proton beams on a PMMA phantom and multi-layer ion chamber, and two GATE simulations of a proton beam incident on a water phantom and 11C PET study show that: (i) the distal fall-off variation of the steepness of the slopes are found to be similar thus validating the sensitivity of the PET technique to the range degradation and (ii) the average of the super-ratios difference between all studies observed is primarily due to the difference in the dose deposited in the media.

The Effects of Sex-Ratio and Density on Locomotor Activity in the House Fly, Musca domestica

PubMed Central

Bahrndorff, Simon; Kjærsgaard, Anders; Pertoldi, Cino; Loeschcke, Volker; Schou, Toke M.; Skovgård, Henrik; Hald, Birthe

2012-01-01

Although locomotor activity is involved in almost all behavioral traits, there is a lack of knowledge on what factors affect it. This study examined the effects of sex—ratio and density on the circadian rhythm of locomotor activity of adult Musca domestica L. (Diptera: Muscidae) using an infra—red light system. Sex—ratio significantly affected locomotor activity, increasing with the percentage of males in the vials. In accordance with other studies, males were more active than females, but the circadian rhythm of the two sexes was not constant over time and changed during the light period. There was also an effect of density on locomotor activity, where males at intermediate densities showed higher activity. Further, the predictability of the locomotor activity, estimated as the degree of autocorrelation of the activity data, increased with the number of males present in the vials both with and without the presence of females. Overall, this study demonstrates that locomotor activity in M. domestica is affected by sex—ratio and density. Furthermore, the predictability of locomotor activity is affected by both sex—ratio, density, and circadian rhythm. These results add to our understanding of the behavioral interactions between houseflies and highlight the importance of these factors when designing behavioral experiments using M. domestica.

Long-Range Solar Activity Predictions: A Reprieve from Cycle #24's Activity

NASA Technical Reports Server (NTRS)

Richon, K.; Schatten, K.

2003-01-01

We discuss the field of long-range solar activity predictions and provide an outlook into future solar activity. Orbital predictions for satellites in Low Earth Orbit (LEO) depend strongly on exospheric densities. Solar activity forecasting is important in this regard, as the solar ultra-violet (UV) and extreme ultraviolet (EUV) radiations inflate the upper atmospheric layers of the Earth, forming the exosphere in which satellites orbit. Rather than concentrate on statistical, or numerical methods, we utilize a class of techniques (precursor methods) which is founded in physical theory. The geomagnetic precursor method was originally developed by the Russian geophysicist, Ohl, using geomagnetic observations to predict future solar activity. It was later extended to solar observations, and placed within the context of physical theory, namely the workings of the Sun s Babcock dynamo. We later expanded the prediction methods with a SOlar Dynamo Amplitude (SODA) index. The SODA index is a measure of the buried solar magnetic flux, using toroidal and poloidal field components. It allows one to predict future solar activity during any phase of the solar cycle, whereas previously, one was restricted to making predictions only at solar minimum. We are encouraged that solar cycle #23's behavior fell closely along our predicted curve, peaking near 192, comparable to the Schatten, Myers and Sofia (1996) forecast of 182+/-30. Cycle #23 extends from 1996 through approximately 2006 or 2007, with cycle #24 starting thereafter. We discuss the current forecast of solar cycle #24, (2006-2016), with a predicted smoothed F10.7 radio flux of 142+/-28 (1-sigma errors). This, we believe, represents a reprieve, in terms of reduced fuel costs, etc., for new satellites to be launched or old satellites (requiring reboosting) which have been placed in LEO. By monitoring the Sun s most deeply rooted magnetic fields; long-range solar activity can be predicted. Although a degree of uncertainty

The dynamic range of response set activation during action sequencing.

PubMed

Behmer, Lawrence P; Crump, Matthew J C

2017-03-01

We show that theories of response scheduling for sequential action can be discriminated on the basis of their predictions for the dynamic range of response set activation during sequencing, which refers to the momentary span of activation states for completed and to-be-completed actions in a response set. In particular, theories allow that future actions in a plan are partially activated, but differ with respect to the width of the range, which refers to the number of future actions that are partially activated. Similarly, theories differ on the width of the range for recently completed actions that are assumed to be rapidly deactivated or gradually deactivated in a passive fashion. We validate a new typing task for measuring momentary activation states of actions across a response set during action sequencing. Typists recruited from Amazon Mechanical Turk copied a paragraph by responding to a "go" signal that usually cued the next letter but sometimes cued a near-past or future letter (n-3, -2, -1, 0, +2, +3). The activation states for producing letters across go-signal positions can be inferred from RTs and errors. In general, we found evidence of graded parallel activation for future actions and rapid deactivation of more distal past actions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Establishing age-associated normative ranges of the cerebral 18F-FDG uptake ratio in children.

PubMed

Hua, Chiaho; Merchant, Thomas E; Li, Xingyu; Li, Yimei; Shulkin, Barry L

2015-04-01

In this study, we reported age-associated ranges of the regional cerebral (18)F-FDG uptake ratio in pediatric patients as a surrogate to normative data from healthy children. (18)F-FDG PET scans of 132 children and adolescents (age, 1-20 y) with non-central nervous system-related diseases and normal-appearing tracer distributions in the brain were retrospectively analyzed. PET images of individual patients were warped to a 3-dimensional reference template. Uptake ratio was calculated for 63 anatomic regions by normalizing the regional count per voxel with the average count per voxel in all regions. Models of regional uptake ratio as a function of age and sex were developed to calculate the 95% prediction interval. The paracentral lobule and cuneus had the highest resting metabolic state among all gray matter regions, whereas the brain stem, uncus, and hippocampus had the lowest uptake. A large left-right asymmetry was present in the angular gyrus and inferior occipital gyrus. Quantitative data of the regression, 95% confidence interval, and 95% prediction interval for each age were summarized for the 63 regions. In 52 of 63 regions, the (18)F-FDG uptake ratio had a significant age effect. The linear model was optimal for 12 regions, whereas the spline model with 1 age knot was a better fit for 40 regions. In children younger than 5 y, frontal and temporal lobes had a lower uptake than parietal and occipital lobes in general. However, uptake in the frontal lobe continued to increase with age but it decreased in the parietal and occipital lobes. Anatomic regions of the brain in children and adolescents exhibited uniquely different (18)F-FDG uptake trends with age. Our results may be useful for studying childhood development and possibly regional metabolic defects in children with traumatic brain injury or central nervous system disorders or children receiving cancer treatment. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Moving target detection in flash mode against stroboscopic mode by active range-gated laser imaging

NASA Astrophysics Data System (ADS)

Zhang, Xuanyu; Wang, Xinwei; Sun, Liang; Fan, Songtao; Lei, Pingshun; Zhou, Yan; Liu, Yuliang

2018-01-01

Moving target detection is important for the application of target tracking and remote surveillance in active range-gated laser imaging. This technique has two operation modes based on the difference of the number of pulses per frame: stroboscopic mode with the accumulation of multiple laser pulses per frame and flash mode with a single shot of laser pulse per frame. In this paper, we have established a range-gated laser imaging system. In the system, two types of lasers with different frequency were chosen for the two modes. Electric fan and horizontal sliding track were selected as the moving targets to compare the moving blurring between two modes. Consequently, the system working in flash mode shows more excellent performance in motion blurring against stroboscopic mode. Furthermore, based on experiments and theoretical analysis, we presented the higher signal-to-noise ratio of image acquired by stroboscopic mode than flash mode in indoor and underwater environment.

Can Serum Neutrophil-to-Lymphocyte Ratio Be a Predictive Biomarker to Help Differentiate Active Chronic Otitis Media From Inactive Chronic Otitis Media?

PubMed

Tansuker, Hasan Deniz; Eroğlu, Sinan; Yenigün, Alper; Taşkin, Ümit; Oktay, Mehmet Faruk

2017-05-01

The authors' aim was to investigate whether serum neutrophil to lymphocyte ratio might be used as a predictive biomarker to help differentiate active from inactive chronic otitis media (COM). Two hundred fifty-nine patients having inactive COM received tympanoplasty without mastoidectomy and were identified as Group 1. On the other hand, 254 patients having active COM received tympanoplasty with mastoidectomy and were identified as Group 2. Routine hemogram tests were performed preoperatively for both the groups. By performing a chart review, white blood cell count, red blood cell count, hemoglobin, hematocrit, platelet, and mean platelet volume values were compared between the groups in an age-matched and sex-matched manner. A total of 513 COM patients with age range of 7 to 65 years were included in the study. Two hundred seventy-five patients (53.6%) were male, 238 were (46.4%) female. Preoperatively both serum neutrophil and lymphocyte counts were significantly higher in Group 2 (P = 0.015 and P = 0.004, respectively). However, the neutrophil-to-lymphocyte ratios between the groups were not significantly different (P = 0.511). No statistically significant differences were identified from preoperative neutrophil-to-lymphocyte ratios between patients having active COM and inactive COM. Level NA.

Metabolic Potential and Activity in Fluids of the Coast Range Ophiolite Microbial Observatory, California, USA

NASA Technical Reports Server (NTRS)

Hoehler, T.; Som, S.; Schrenk, M.; McCollom, T.; Cardace, D.

2016-01-01

Metabolic potential and activity associated with hydrogen and carbon monoxide were characterized in fluids sampled from the the Coast Range Ophiolite Microbial Observatory (CROMO). CROMO consists of two clusters of science-dedicated wells drilled to varying depths up to 35m in the actively serpentinizing, Jurassic-age Coast Range Ophiolite of Northern California, along with a suite of pre-existing monitoring wells at the same site. Consistent with the fluid chemistry observed in other serpentinizing systems, CROMO fluids are highly alkaline, with pH up to 12.5, high in methane, with concentrations up 1600 micromolar, and low in dissolved inorganic carbon (DIC), with concentrations of 10's to 100's of micromolar. CROMO is conspicuous for fluid H2 concentrations that are consistently sub-micromolar, orders of magnitude lower than is typical of other systems. However, higher H2 concentrations (10's -100's of micromolar) at an earlier stage of fluid chemical evolution are predicted by, or consistent with: thermodynamic models for fluid chemistry based on parent rock composition equivalent to local peridotite and with water:rock ratio constrained by observed pH; the presence of magnetite at several wt% in CROMO drill cores; and concentrations of formate and carbon monoxide that would require elevated H2 if formed in equilibrium with H2 and DIC. Calculated Gibbs energy changes for reaction of H2 and CO in each of several metabolisms, across the range of fluid composition encompassed by the CROMO wells, range from bioenergetically feasible (capable of driving ATP synthesis) to thermodynamically unfavorable. Active consumption relative to killed controls was observed for both CO and H2 during incubation of fluids from the pre-existing monitoring wells; in incubations of freshly cored solids, consumption was only observed in one sample set (corresponding to the lowest pH) out of three. The specific metabolisms by which H2 and CO are consumed remain to be determined.

Characterizing proton-activated materials to develop PET-mediated proton range verification markers

NASA Astrophysics Data System (ADS)

Cho, Jongmin; Ibbott, Geoffrey S.; Kerr, Matthew D.; Amos, Richard A.; Stingo, Francesco C.; Marom, Edith M.; Truong, Mylene T.; Palacio, Diana M.; Betancourt, Sonia L.; Erasmus, Jeremy J.; DeGroot, Patricia M.; Carter, Brett W.; Gladish, Gregory W.; Sabloff, Bradley S.; Benveniste, Marcelo F.; Godoy, Myrna C.; Patil, Shekhar; Sorensen, James; Mawlawi, Osama R.

2016-06-01

Conventional proton beam range verification using positron emission tomography (PET) relies on tissue activation alone and therefore requires particle therapy PET whose installation can represent a large financial burden for many centers. Previously, we showed the feasibility of developing patient implantable markers using high proton cross-section materials (18O, Cu, and 68Zn) for in vivo proton range verification using conventional PET scanners. In this technical note, we characterize those materials to test their usability in more clinically relevant conditions. Two phantoms made of low-density balsa wood (~0.1 g cm-3) and beef (~1.0 g cm-3) were embedded with Cu or 68Zn foils of several volumes (10-50 mm3). The metal foils were positioned at several depths in the dose fall-off region, which had been determined from our previous study. The phantoms were then irradiated with different proton doses (1-5 Gy). After irradiation, the phantoms with the embedded foils were moved to a diagnostic PET scanner and imaged. The acquired data were reconstructed with 20-40 min of scan time using various delay times (30-150 min) to determine the maximum contrast-to-noise ratio. The resultant PET/computed tomography (CT) fusion images of the activated foils were then examined and the foils’ PET signal strength/visibility was scored on a 5 point scale by 13 radiologists experienced in nuclear medicine. For both phantoms, the visibility of activated foils increased in proportion to the foil volume, dose, and PET scan time. A linear model was constructed with visibility scores as the response variable and all other factors (marker material, phantom material, dose, and PET scan time) as covariates. Using the linear model, volumes of foils that provided adequate visibility (score 3) were determined for each dose and PET scan time. The foil volumes that were determined will be used as a guideline in developing practical implantable markers.

Field Demonstrations of Active Laser Ranging with Sub-mm Precision

NASA Technical Reports Server (NTRS)

Chen, Yijiang; Birnbaum, Kevin M.; Hemmati, Hamid

2011-01-01

Precision ranging between planets will provide valuable information for scientific studies of the solar system and fundamental physics. Current passive ranging techniques using retro-reflectors are limited to the Earth-Moon distance due to the 1/R? losses. We report on a laboratory realization and field implementation of active laser ranging in real-time with two terminals, emulating interplanetary distance. Sub-millimeter accuracy is demonstrated.

Middle-Range Theory: Coping and Adaptation with Active Aging.

PubMed

Salazar-Barajas, Martha Elba; Salazar-González, Bertha Cecilia; Gallegos-Cabriales, Esther Carlota

2017-10-01

Various disciplines focus on a multiplicity of aspects of aging: lifestyles, personal biological factors, psychological conditions, health conditions, physical environment, and social and economic factors. The aforementioned are all related to the determinants of active aging. The aim is to describe the development of a middle-range theory based on coping and adaptation with active aging. Concepts and relationships derived from Roy's model of adaptation are included. The proposed concepts are hope, health habits, coping with aging, social relations, and active aging.

Optimal waist-to-hip ratios in women activate neural reward centers in men.

PubMed

Platek, Steven M; Singh, Devendra

2010-02-05

Secondary sexual characteristics convey information about reproductive potential. In the same way that facial symmetry and masculinity, and shoulder-to-hip ratio convey information about reproductive/genetic quality in males, waist-to-hip-ratio (WHR) is a phenotypic cue to fertility, fecundity, neurodevelopmental resources in offspring, and overall health, and is indicative of "good genes" in women. Here, using fMRI, we found that males show activation in brain reward centers in response to naked female bodies when surgically altered to express an optimal (approximately 0.7) WHR with redistributed body fat, but relatively unaffected body mass index (BMI). Relative to presurgical bodies, brain activation to postsurgical bodies was observed in bilateral orbital frontal cortex. While changes in BMI only revealed activation in visual brain substrates, changes in WHR revealed activation in the anterior cingulate cortex, an area associated with reward processing and decision-making. When regressing ratings of attractiveness on brain activation, we observed activation in forebrain substrates, notably the nucleus accumbens, a forebrain nucleus highly involved in reward processes. These findings suggest that an hourglass figure (i.e., an optimal WHR) activates brain centers that drive appetitive sociality/attention toward females that represent the highest-quality reproductive partners. This is the first description of a neural correlate implicating WHR as a putative honest biological signal of female reproductive viability and its effects on men's neurological processing.

Activity ratios in soil contaminated by the source of different reactor condition in the FDNPP accident

NASA Astrophysics Data System (ADS)

Satou, Yukihiko; Sueki, Keisuke; Sasa, Kimikazu; Matsunaka, Tetsuya; Shibayama, Nao; Takahashi, Tsutomu; Kinoshita, Norikazu

2014-05-01

The Fukushima Dai-ichi Nuclear power plant (FDNPP) accident caused radioactive contamination on the surface soil at Fukushima and its adjacent prefectures. Substantial contamination has been found in the northwestern area from the FDNPP, according to the airborne monitoring and ground base survey by the Japanese government. Activity ratios would have characteristic information on emission sources because each relevant reactor had different amount of radionuclide and different activity ratio. The ratios can be used to clarify more detailed source and process in the contamination. We have addressed to consider them in Namie town, northwestern region from the FDNPP. This study focused on the gamma-ray emitting radionuclides of 134Cs, 137Cs, and 110mAg. The activities were decay-corrected as of 11th March, 2011 when all nuclear reactors scrammed. Data of activity ratios by our results and the Japanese official report classified the investigated northwestern region into 3 groups. Ratios of 0.02 for 110mAg/137Cs and 0.90 for 134Cs/137Cs were observed in the northern region of 15 km inside from the FDNPP. On the other hand, two kinds of 110mAg/137Cs ratios of 0.005 and 0.002 were distributed broadly in the region 60 km away from the plant. The 134Cs/137Cs ratio was 0.98 there. The activity ratios of 110mAg/137Cs and 134Cs/137Cs in the northern region from the FDNPP correspond to those of nuclear fuel in Unit 1 according to estimation using the ORIGEN code. The 134Cs/137Cs in the northwestern area from FDNPP agrees with that of Unit 2 and 3. The 110mAg/137Cs ratios of 0.005 and0.002 are 1/5 - 1/10 of the Unit 2 and 3. Official report has announced that discharges of the radionuclides from Unit 2 and 3 occurred on 14th March, 2011. It is known that contamination in the northwestern region from the FDNPP took place on 15th March, 2011. Plausible species for silver in reactor core, metal, and halide etc. have higher boiling point than those species for cesium. The core would

The Effect of Alkaline Activator Ratio on the Compressive Strength of Fly Ash-Based Geopolymer Paste

NASA Astrophysics Data System (ADS)

Lăzărescu, A. V.; Szilagyi, H.; Baeră, C.; Ioani, A.

2017-06-01

Alkaline activation of fly ash is a particular procedure in which ash resulting from a power plant combined with a specific alkaline activator creates a solid material when dried at a certain temperature. In order to obtain desirable compressive strengths, the mix design of fly ash based geopolymer pastes should be explored comprehensively. To determine the preliminary compressive strength for fly ash based geopolymer paste using Romanian material source, various ratios of Na2SiO3 solution/ NaOH solution were produced, keeping the fly ash/alkaline activator ratio constant. All the mixes were then cured at 70 °C for 24 hours and tested at 2 and 7 days, respectively. The aim of this paper is to present the preliminary compressive strength results for producing fly ash based geopolymer paste using Romanian material sources, the effect of alkaline activators ratio on the compressive strength and studying the directions for future research.

Atmospheric residence time of (210)Pb determined from the activity ratios with its daughter radionuclides (210)Bi and (210)Po.

PubMed

Semertzidou, P; Piliposian, G T; Appleby, P G

2016-08-01

The residence time of (210)Pb created in the atmosphere by the decay of gaseous (222)Rn is a key parameter controlling its distribution and fallout onto the landscape. These in turn are key parameters governing the use of this natural radionuclide for dating and interpreting environmental records stored in natural archives such as lake sediments. One of the principal methods for estimating the atmospheric residence time is through measurements of the activities of the daughter radionuclides (210)Bi and (210)Po, and in particular the (210)Bi/(210)Pb and (210)Po/(210)Pb activity ratios. Calculations used in early empirical studies assumed that these were governed by a simple series of equilibrium equations. This approach does however have two failings; it takes no account of the effect of global circulation on spatial variations in the activity ratios, and no allowance is made for the impact of transport processes across the tropopause. This paper presents a simple model for calculating the distributions of (210)Pb, (210)Bi and (210)Po at northern mid-latitudes (30°-65°N), a region containing almost all the available empirical data. By comparing modelled (210)Bi/(210)Pb activity ratios with empirical data a best estimate for the tropospheric residence time of around 10 days is obtained. This is significantly longer than earlier estimates of between 4 and 7 days. The process whereby (210)Pb is transported into the stratosphere when tropospheric concentrations are high and returned from it when they are low, significantly increases the effective residence time in the atmosphere as a whole. The effect of this is to significantly enhance the long range transport of (210)Pb from its source locations. The impact is illustrated by calculations showing the distribution of (210)Pb fallout versus longitude at northern mid-latitudes. Copyright © 2016 Elsevier Ltd. All rights reserved.

A terahertz EO detector with large dynamical range, high modulation depth and signal-noise ratio

NASA Astrophysics Data System (ADS)

Pan, Xinjian; Cai, Yi; Zeng, Xuanke; Zheng, Shuiqin; Li, Jingzhen; Xu, Shixiang

2017-05-01

The paper presents a novel design for terahertz (THz) free-space time domain electro-optic (EO) detection where the static birefringent phases of the two balanced arms are set close to zero but opposite to each other. Our theoretical and numerical analyses show this design has much stronger ability to cancel the optical background noise than both THz ellipsometer and traditional crossed polarizer geometry (CPG). Its optical modulation depth is about twice as high as that of traditional CPG, but about ten times as high as that of THz ellipsometer. As for the dynamical range, our improved design is comparable to the THz ellipsometer but obviously larger than the traditional CPG. Some experiments for comparing our improved CPG with traditional CPG agree well with the corresponding theoretical predictions. Our experiments also show that the splitting ratio of the used non-polarization beam splitter is critical for the performance of our design.

Comprehensive analysis of proton range uncertainties related to patient stopping-power-ratio estimation using the stoichiometric calibration

PubMed Central

Yang, M; Zhu, X R; Park, PC; Titt, Uwe; Mohan, R; Virshup, G; Clayton, J; Dong, L

2012-01-01

The purpose of this study was to analyze factors affecting proton stopping-power-ratio (SPR) estimations and range uncertainties in proton therapy planning using the standard stoichiometric calibration. The SPR uncertainties were grouped into five categories according to their origins and then estimated based on previously published reports or measurements. For the first time, the impact of tissue composition variations on SPR estimation was assessed and the uncertainty estimates of each category were determined for low-density (lung), soft, and high-density (bone) tissues. A composite, 95th percentile water-equivalent-thickness uncertainty was calculated from multiple beam directions in 15 patients with various types of cancer undergoing proton therapy. The SPR uncertainties (1σ) were quite different (ranging from 1.6% to 5.0%) in different tissue groups, although the final combined uncertainty (95th percentile) for different treatment sites was fairly consistent at 3.0–3.4%, primarily because soft tissue is the dominant tissue type in human body. The dominant contributing factor for uncertainties in soft tissues was the degeneracy of Hounsfield Numbers in the presence of tissue composition variations. To reduce the overall uncertainties in SPR estimation, the use of dual-energy computed tomography is suggested. The values recommended in this study based on typical treatment sites and a small group of patients roughly agree with the commonly referenced value (3.5%) used for margin design. By using tissue-specific range uncertainties, one could estimate the beam-specific range margin by accounting for different types and amounts of tissues along a beam, which may allow for customization of range uncertainty for each beam direction. PMID:22678123

Conceptual study of an advanced supersonic technology transport (AST-107) for transpacific range using low-bypass-ratio turbofan engines

NASA Technical Reports Server (NTRS)

Morris, S. J., Jr.; Foss, W. E., Jr.; Neubauer, M. J., Jr.

1980-01-01

An advanced supersonic technology configuration concept designated the AST-107, using a low bypass ratio turbofan engine, is described and analyzed. The aircraft had provisions for 273 passengers arranged five abreast. The cruise Mach number was 2.62. The mission range for the AST-107 was 8.48 Mm (4576 n.mi.) and an average lift drag ratio of 9.15 during cruise was achieved. The available lateral control was not sufficient for the required 15.4 m/s (30 kt) crosswind landing condition, and a crosswind landing gear or a significant reduction in dihedral effect would be necessary to meet this requirement. The lowest computed noise levels, including a mechanical suppressor noise reduction of 3 EPNdB at the flyover and sideline monitoring stations, were 110.3 EPNdB (sideline noise), 113.1 EPNdB (centerline noise) and 110.5 EPNdB (approach noise).

Using Multitemporal and Multispectral Airborne Lidar to Assess Depth of Peat Loss and Correspondence With a New Active Normalized Burn Ratio for Wildfires

NASA Astrophysics Data System (ADS)

Chasmer, L. E.; Hopkinson, C. D.; Petrone, R. M.; Sitar, M.

2017-12-01

Accuracy of depth of burn (an indicator of consumption) in peatland soils using prefire and postfire airborne light detection and ranging (lidar) data is determined within a wetland-upland forest environment near Fort McMurray, Alberta, Canada. The relationship between peat soil burn depth and an "active" normalized burn ratio (ANBR) is also examined beneath partially and fully burned forest and understory canopies using state-of-the-art active reflectance from a multispectral lidar compared with normalized burn ratio (NBR) derived from Landsat 7 ETM+. We find significant correspondence between depth of burn, lidar-derived ANBR, and difference NBR (dNBR) from Landsat. However, low-resolution optical imagery excludes peatland burn losses in transition zones, which are highly sensitive to peat loss via combustion. The findings presented here illustrate the utility of this new remote sensing technology for expanding an area of research where it has previously been challenging to spatially detect and quantify such wildfire burn losses.

Changes in cervical range of motion, flexion-relaxation ratio and pain with visual display terminal work.

PubMed

Shin, Seung-Je; Yoo, Won-Gyu

2014-01-01

The static posture in visual display terminal (VDT) workers results in increased forward neck flexion and increased static muscle tension in the neck and shoulder regions. However, few studies have objectively quantified the change in head posture induced shoulder pain during VDT work. This study elucidated changes in pressure pain in the upper trapezius muscles, cervical ROM, and the cervical flexion--relaxation ratio after continuous long-term VDT work. Twelve young VDT workers were recruited. The pressure pain of the upper trapezius muscles, active CROM, and cervical flexion--relaxation ratio were measured in all subjects once before and once after VDT work. The pressure pain threshold of the right upper trapezius muscle was 6.9 ± 1.6 lb before VDT work and 6.1 ± 1.0 lb after VDT work, revealing a significant increase with VDT work. The cervical extension, left and right lateral flexion, and left rotation measurers decreased significantly with VDT work. We postulate that even short-term VDT work has the potential to cause problems. It is necessary to develop a CROM self-measuring device and to monitor patients' musculoskeletal changes frequently.

The Intrinsic Eddington Ratio Distribution of Active Galactic Nuclei in Young Galaxies from SDSS

NASA Astrophysics Data System (ADS)

Jones, Mackenzie L.; Hickox, Ryan C.; Black, Christine; Hainline, Kevin Nicholas; DiPompeo, Michael A.

2016-04-01

An important question in extragalactic astronomy concerns the distribution of black hole accretion rates, i.e. the Eddington ratio distribution, of active galactic nuclei (AGN). Specifically, it is matter of debate whether AGN follow a broad distribution in accretion rates, or if the distribution is more strongly peaked at characteristic Eddington ratios. Using a sample of galaxies from SDSS DR7, we test whether an intrinsic Eddington ratio distribution that takes the form of a broad Schechter function is in fact consistent with previous work that suggests instead that young galaxies in optical surveys have a more strongly peaked lognormal Eddington ratio distribution. Furthermore, we present an improved method for extracting the AGN distribution using BPT diagnostics that allows us to probe over one order of magnitude lower in Eddington ratio, counteracting the effects of dilution by star formation. We conclude that the intrinsic Eddington ratio distribution of optically selected AGN is consistent with a power law with an exponential cutoff, as is observed in the X-rays. This work was supported in part by a NASA Jenkins Fellowship.

DUST IN ACTIVE GALACTIC NUCLEI: ANOMALOUS SILICATE TO OPTICAL EXTINCTION RATIOS?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyu, Jianwei; Hao, Lei; Li, Aigen, E-mail: haol@shao.ac.cn

Dust plays a central role in the unification theory of active galactic nuclei (AGNs). However, little is known about the nature (e.g., size, composition) of the dust that forms a torus around the AGN. In this Letter, we report a systematic exploration of the optical extinction (A{sub V} ) and the silicate absorption optical depth (Δτ{sub 9.7}) of 110 type 2 AGNs. We derive A{sub V} from the Balmer decrement based on the Sloan Digital Sky Survey data, and Δτ{sub 9.7} from the Spitzer/InfraRed Spectrograph data. We find that with a mean ratio of (A{sub V} /Δτ{sub 9.7}) ≲ 5.5, themore » optical-to-silicate extinction ratios of these AGNs are substantially lower than that of the Galactic diffuse interstellar medium (ISM) for which A{sub V} /Δτ{sub 9.7} ≈ 18.5. We argue that the anomalously low A{sub V} /Δτ{sub 9.7} ratio could be due to the predominance of larger grains in the AGN torus compared to that in the Galactic diffuse ISM.« less

Nicotinamide nucleotide transhydrogenase from Rhodobacter capsulatus; the H+/H- ratio and the activation state of the enzyme during reduction of acetyl pyridine adenine dinucleotide.

PubMed

Palmer, T; Jackson, J B

1992-02-21

Chromatophores from Rhodobacter capsulatus were incubated in the dark with NADPH and acetylpyridineadenine dinucleotide (AcPdAD+) in the presence of different concentrations of myxothiazol. The transhydrogenase activity was monitored until an appropriate mass action ratio, [AcPdAD+][NADPH]/[AcPdADH][NADP+], was reached. The sample was then illuminated and the initial rate of either AcPdAD+ reduction by NADPH or AcPdADH oxidation by NADP+ was recorded. The ratio of H+ translocated per H- equivalent transferred by transhydrogenase was calculated from the value of the membrane potential (delta pH = 0) at which illumination caused no net reaction in either direction. The mean value for the H+/H- ratio was 0.55. At greater values of [AcPdAD+][NADPH]/[AcPdADH][NADP+] than were employed in the above experiments and over a wider range of concentrations of myxothiazol, it was found that incremental increases in the membrane potential always gave rise to a decrease, never an increase in the rate of AcPdAD+ reduction. In contrast to the H(+)-ATP synthase, there is no evidence of any activation/deactivation of H(+)-transhydrogenase by the protonmotive force.

Network feedback regulates motor output across a range of modulatory neuron activity

PubMed Central

Spencer, Robert M.

2016-01-01

Modulatory projection neurons alter network neuron synaptic and intrinsic properties to elicit multiple different outputs. Sensory and other inputs elicit a range of modulatory neuron activity that is further shaped by network feedback, yet little is known regarding how the impact of network feedback on modulatory neurons regulates network output across a physiological range of modulatory neuron activity. Identified network neurons, a fully described connectome, and a well-characterized, identified modulatory projection neuron enabled us to address this issue in the crab (Cancer borealis) stomatogastric nervous system. The modulatory neuron modulatory commissural neuron 1 (MCN1) activates and modulates two networks that generate rhythms via different cellular mechanisms and at distinct frequencies. MCN1 is activated at rates of 5–35 Hz in vivo and in vitro. Additionally, network feedback elicits MCN1 activity time-locked to motor activity. We asked how network activation, rhythm speed, and neuron activity levels are regulated by the presence or absence of network feedback across a physiological range of MCN1 activity rates. There were both similarities and differences in responses of the two networks to MCN1 activity. Many parameters in both networks were sensitive to network feedback effects on MCN1 activity. However, for most parameters, MCN1 activity rate did not determine the extent to which network output was altered by the addition of network feedback. These data demonstrate that the influence of network feedback on modulatory neuron activity is an important determinant of network output and feedback can be effective in shaping network output regardless of the extent of network modulation. PMID:27030739

Network feedback regulates motor output across a range of modulatory neuron activity.

PubMed

Spencer, Robert M; Blitz, Dawn M

2016-06-01

Modulatory projection neurons alter network neuron synaptic and intrinsic properties to elicit multiple different outputs. Sensory and other inputs elicit a range of modulatory neuron activity that is further shaped by network feedback, yet little is known regarding how the impact of network feedback on modulatory neurons regulates network output across a physiological range of modulatory neuron activity. Identified network neurons, a fully described connectome, and a well-characterized, identified modulatory projection neuron enabled us to address this issue in the crab (Cancer borealis) stomatogastric nervous system. The modulatory neuron modulatory commissural neuron 1 (MCN1) activates and modulates two networks that generate rhythms via different cellular mechanisms and at distinct frequencies. MCN1 is activated at rates of 5-35 Hz in vivo and in vitro. Additionally, network feedback elicits MCN1 activity time-locked to motor activity. We asked how network activation, rhythm speed, and neuron activity levels are regulated by the presence or absence of network feedback across a physiological range of MCN1 activity rates. There were both similarities and differences in responses of the two networks to MCN1 activity. Many parameters in both networks were sensitive to network feedback effects on MCN1 activity. However, for most parameters, MCN1 activity rate did not determine the extent to which network output was altered by the addition of network feedback. These data demonstrate that the influence of network feedback on modulatory neuron activity is an important determinant of network output and feedback can be effective in shaping network output regardless of the extent of network modulation. Copyright © 2016 the American Physiological Society.

Results of an Advanced Fan Stage Operating Over a Wide Range of Speed and Bypass Ratio. Part 2; Comparison of CFD and Experimental Results

NASA Technical Reports Server (NTRS)

Celestina, Mark L.; Suder, Kenneth L.; Kulkarni, Sameer

2010-01-01

NASA and GE teamed to design and build a 57 percent engine scaled fan stage for a Mach 4 variable cycle turbofan/ramjet engine for access to space with multipoint operations. This fan stage was tested in NASA's transonic compressor facility. The objectives of this test were to assess the aerodynamic and aero mechanic performance and operability characteristics of the fan stage over the entire range of engine operation including: 1) sea level static take-off; 2) transition over large swings in fan bypass ratio; 3) transition from turbofan to ramjet; and 4) fan wind-milling operation at high Mach flight conditions. This paper will focus on an assessment of APNASA, a multistage turbomachinery analysis code developed by NASA, to predict the fan stage performance and operability over a wide range of speeds (37 to 100 percent) and bypass ratios.

Diet and waist-to-hip ratio: important predictors of lipoprotein levels in sedentary and active young men with no evidence of cardiovascular disease.

PubMed

Mansfield, E; McPherson, R; Koski, K G

1999-11-01

-to-hip ratio in the primary prevention of coronary heart disease is a simple and cost-effective measure to predict development of abnormal lipoprotein profiles in young men. Specific dietary recommendations include adoption of a heart-healthy diet with emphasis on monounsaturated fatty acids (10% to 12% of energy or one third of total fat intake) and the suggestion that small amounts of alcohol (< 3 drinks per week) may, indeed, be beneficial. Because alcohol and waist-to-hip ratio were both important predictors of LDL-C level, even in active young men, the consumption of low levels of alcohol may be beneficial only if waist-to-hip ratio is maintained within the healthful range by achieving an appropriate balance of physical activity and macronutrient intake.

[Non vascularized toe phalangeal transfers for symbrachydactyly. Active range of motion without joint reconstruction].

PubMed

Leca, J-B; Auquit Auckbur, I; Bachy, B; Milliez, P-Y

2008-12-01

Symbrachydactyly is a rare congenital malformation of the hand and its treatment is controversial. Non vascularized toe phalangeal transfers have been used for management of short digits for three children. Six phalanges have been harvested complete with their periosteum. No joint reconstruction has been performed and all children have undergone surgery at a young age. Four of six digits involved have an active range of motion (range 30 to 105 degrees ). All authors who have reported active range of motion of toe phalangeal transfers have performed joint reconstruction. Here, we report obtaining active range of motion of phalangeal transfers without necessity of joint reconstruction.

Using Ratio Analysis to Evaluate Financial Performance.

ERIC Educational Resources Information Center

Minter, John; And Others

1982-01-01

The ways in which ratio analysis can help in long-range planning, budgeting, and asset management to strengthen financial performance and help avoid financial difficulties are explained. Types of ratios considered include balance sheet ratios, net operating ratios, and contribution and demand ratios. (MSE)

Microwave synthesis and photocatalytic activities of ZnO bipods with different aspect ratios

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Fazhe; Zhao, Zengdian; Qiao, Xueliang, E-mail: xuelqiao@163.com

2016-02-15

Highlights: • We synthesized linked ZnO nanorods by a facile microwave method. • The effect of reaction parameters on ZnO was investigated. • ZnO bipods with different aspect ratios were prepared. • The photocatalytic performance of ZnO bipods was evaluated. - Abstract: Linked ZnO nanorods have been successfully prepared via a facile microwave method without any post-synthesis treatment. The X-ray diffraction (XRD) patterns indicated the precursor had completely transformed into the pure ZnO crystal. The images of field emitting scanning electron microscope (FESEM) and transmission electron microscope (TEM) showed that linked ZnO nanorods consisted predominantly of ZnO bipods. The formationmore » process of the ZnO bipods was clearly discussed. ZnO bipods with different aspect ratios have been obtained by tuning the concentrations of reagents and microwave power. Moreover, the photocatalytic performance of ZnO bipods with different aspect ratios for degradation of methylene blue was systematically evaluated. The results of photocatalytic experiments showed that the photocatalytic activity increased with the aspect ratios of ZnO bipods increased. The reason is that ZnO bipods with larger aspect ratio have higher surface area, which can absorb more MB molecules to react with ·OH radicals.« less

Correlation Between Cometary Gas/Dust Ratios and Heliocentric Distance

NASA Astrophysics Data System (ADS)

Harrington, Olga; Womack, Maria; Lastra, Nathan

2017-10-01

We compiled CO-based gas/dust ratios for several comets out to heliocentric distances, rh, of 8 au to probe whether there is a noticeable change in comet behavior over the range that water-ice sublimation starts. Previously, gas/dust ratios were calculated for an ensemble of comets using Q(CO2)/efp values derived from infrared measurements, which showed that the gas/dust ratio follows a rh-2 within 4 AU, but is flat at greater distances (Bauer et al. 2015). Our project focuses on gas/dust ratios for which CO is assumed to be the dominant gas, in order to test whether similar breaks in slope occur for CO. The gas/dust ratios were calculated from measurements of CO production rates (mostly from millimeter-wavelength spectroscopy) and reflected sunlight of comets (mostly via reported visual magnitudes of dusty comets). We present our new CO-based gas/dust ratios at different heliocentric distances, compare them to existing CO2-based gas/dust ratios, and discuss implications for CO-driven and CO2-driven activity. We discuss O.H. acknowledges support from the Hartmann Student Travel Grant program. M.W. acknowledges support from NSF grant AST-1615917.

Composite flexible skin with large negative Poisson’s ratio range: numerical and experimental analysis

NASA Astrophysics Data System (ADS)

Chen, Y. J.; Scarpa, F.; Farrow, I. R.; Liu, Y. J.; Leng, J. S.

2013-04-01

This paper describes the manufacturing, characterization and parametric modeling of a novel fiber-reinforced composite flexible skin with in-plane negative Poisson’s ratio (auxetic) behavior. The elastic mechanical performance of the auxetic skin is evaluated using a three-dimensional analytical model based on the classical laminate theory (CLT) and Sun’s thick laminate theory. Good agreement is observed between in-plane Poisson’s ratios and Young’s moduli of the composite skin obtained by the theoretical model and the experimental results. A parametric analysis carried out with the validated model shows that significant changes in the in-plane negative Poisson’s ratio can be achieved through different combinations of matrix and fiber materials and stacking sequences. It is also possible to identify fiber-reinforced composite skin configurations with the same in-plane auxeticity but different orthotropic stiffness performance, or the same orthotropic stiffness performance but different in-plane auxeticity. The analysis presented in this work provides useful guidelines to develop and manufacture flexible skins with negative Poisson’s ratio for applications focused on morphing aircraft wing designs.

Ectoenzymatic ratios in relation to particulate organic matter distribution (Ross Sea, Antarctica).

PubMed

Misic, C; Povero, P; Fabiano, M

2002-10-01

The results of a study on ectoenzymatic activity (the enzyme activity bound to particles larger than 0.2 micro m) and its relation to organic particle concentration are reported here. The sampling was carried out during the 1994 Antarctic spring, at a fixed station (Station 11) in the polynya of the Ross Sea, an area characterized by quick changes in sea ice cover. The sampling was repeated 4 times over a 20-day time period. The particulate organic matter distribution followed the physical structure of the water column, which depends on ice dynamics and is mainly determined by salinity. In the mixed-water surface layer (0-50 m) the concentrations were higher (on average 65.6 micro gC/L) than in the deeper water layer (50 m-bottom) (on average 19.1 micro gC/L). This distribution and quality, expressed by the protein:carbohydrate ratio, linked the particulate organic matter to the phytoplanktonic bloom which was in progress in the area. We determined the kinetic parameters of the glycolytic and proteolytic ectoenzymes and also the total activity for the proteolytic enzyme, in order to evaluate the contribution of the particle-bound activity. We observed higher values in the surface layer than in the deeper layer. b-Glucosidase activity ranged between 0.03 and 0.92 nmol L(-1) h(-1); b-N-acetylglucosaminidase activity was in the range of 0.04-0.58 nmol (L-1) (h-1). The total proteolytic activity (leucine aminopeptidase) ranged between 0.85 and 33.71 nmol L(-1) (h-1). The ectoproteolytic activity was about 35-60% of the total. The Km values were slightly higher for the proteolytic activity (on average 0.43 micro M for ectoproteolytic activity and 0.58 micro M for total proteolytic activity) than for the b-glucosidase (on average 0.36 micro M) and b-N-acetylglucosaminidase (on average 0.17 micro M), showing no remarkable variations in the water column. The ectoenzymatic ratios and their relationship with particulate organic substrates confirm the close link between

Out-of-range international normalized ratio values and healthcare cost among new warfarin patients with non-valvular atrial fibrillation.

PubMed

Nelson, Winnie W; Wang, Li; Baser, Onur; Damaraju, C V; Schein, Jeffrey R

2015-05-01

Patients with out-of-range international normalized ratio (INR) values <2.0 and >3.0 have been associated with increased risk of thromboembolic and bleeding events. INR monitoring is costly, because of associated physician and nurse time, laboratory resource use, and dose adjustments. This study assessed the healthcare cost burden associated with out-of-range INR among warfarin initiator patients diagnosed with non-valvular atrial fibrillation (NVAF) in the US Veterans Health Administration (VHA) population. Adult NVAF patients (≥18 years) initiating warfarin were selected from the VHA dataset for the study period October 1, 2007-September 30, 2012. Only valid INR measurements (0.5 ≤ INR ≤ 20) were examined for the follow-up period, from the index date (warfarin initiation date) until the end of warfarin exposure or death. All-cause healthcare costs within 30 days were measured starting from the second month (31 days post-index date) to the end of the study period. Costs for inpatient stays, emergency room, outpatient facility, physician office visits, and other services were computed separately. Multiple regression was performed using the generalized linear model for overall cost analysis. In total, 29,463 patients were included in the study sample. Mean costs for out-of-range INR ranged from $3419 to $5126. Inpatient, outpatient, outpatient pharmacy, and total costs were significantly higher after patients experienced out-of-range results (INR < 2, INR > 3), compared with in-range INR (2 ≤ INR ≤ 3). When exposed to out-of-range INR, patients also incurred higher mean total costs within 2-6 months ($3840-$5820) than after the first 6 months ($2789-$3503) of warfarin therapy. In the VHA population, INR measures outside of the 2-3 range were associated with significantly higher healthcare costs. Increased costs were especially apparent when INR values were below 2, although INR measures above 3 were also associated with higher costs

A non-radioactive method for measuring Rubisco activase activity in the presence of variable ATP: ADP ratios, including modifications for measuring the activity and activation state of Rubisco.

PubMed

Scales, Joanna C; Parry, Martin A J; Salvucci, Michael E

2014-03-01

Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) catalyzes carboxylation of ribulose-1,5-bisphosphate, the first in a series of reactions leading to the incorporation of atmospheric CO₂ into biomass. Rubisco requires Rubisco activase (RCA), an AAA+ ATPase that reactivates Rubisco by remodelling the conformation of inhibitor-bound sites. RCA is regulated by the ratio of ADP:ATP, with the precise response potentiated by redox regulation of the alpha-isoform. Measuring the effects of ADP on the activation of Rubisco by RCA using the well-established photometric assay is problematic because of the adenine nucleotide requirement of 3-phosphoglycerate (3-PGA) kinase. Described here is a novel assay for measuring RCA activity in the presence of variable ratios of ADP:ATP. The assay couples the formation of 3-PGA from ribulose 1,5-bisphosphate and CO₂ to NADH oxidation through cofactor-dependent phosphoglycerate mutase, enolase, PEP carboxylase and malate dehydrogenase. The assay was used to determine the effects of Rubisco and RCA concentration and ADP:ATP ratio on RCA activity, and to measure the activation of a modified Rubisco by RCA. Variations of the basic assay were used to measure the activation state of Rubisco in leaf extracts and the activity of purified Rubisco. The assay can be automated for high-throughput processing by conducting the reactions in two stages.

Modeling the ratio of photosynthetically active radiation to broadband global solar radiation using ground and satellite-based data in the tropics

NASA Astrophysics Data System (ADS)

Janjai, S.; Wattan, R.; Sripradit, A.

2015-12-01

Data from four stations in Thailand are used to model the ratio of photosynthetically active radiation (PAR) to broadband global solar radiation. The model expresses the ratio of PAR-to-broadband global solar radiation as a function of cloud index, aerosol optical depth, precipitable water, total ozone column and solar zenith angle. Data from the MTSAT-1R and OMI/AURA satellites are used to estimate the cloud index and total ozone column, respectively at each of the four stations, while aerosol optical depth and precipitable water are retrieved from Aerosol Robotic Network (AERONET) sunphotometer measurements, also available at each station. When tested against hourly measurements, the model exhibits a coefficient of variance (R2) equal to or better than 0.96, and root mean square difference (RMSD) in the range of 7.3-7.9% and mean bias difference (MBD) of -4.5% to 3.5%. The model compares favorably with other existing models.

Reference ranges for urinary concentrations and ratios of endogenous steroids, which can be used as markers for steroid misuse, in a Caucasian population of athletes.

PubMed

Van Renterghem, Pieter; Van Eenoo, Peter; Geyer, Hans; Schänzer, Wilhelm; Delbeke, Frans T

2010-02-01

The detection of misuse with naturally occurring steroids is a great challenge for doping control laboratories. Intake of natural anabolic steroids alters the steroid profile. Thus, screening for exogenous use of these steroids can be established by monitoring a range of endogenous steroids, which constitute the steroid profile, and evaluate their concentrations and ratios against reference ranges. Elevated values of the steroid profile constitute an atypical finding after which a confirmatory IRMS procedure is needed to unequivocally establish the exogenous origin of a natural steroid. However, the large inter-individual differences in urinary steroid concentrations and the recent availability of a whole range of natural steroids (e.g. dehydroepiandrosterone and androstenedione) which each exert a different effect on the monitored parameters in doping control complicate the interpretation of the current steroid profile. The screening of an extended steroid profile can provide additional parameters to support the atypical findings and can give specific information upon the steroids which have been administered. The natural concentrations of 29 endogenous steroids and 11 ratios in a predominantly Caucasian population of athletes were determined. The upper reference values at 97.5%, 99% and 99.9% levels were assessed for male (n=2027) and female (n=1004) populations. Monitoring minor metabolites and evaluation of concentration ratios with respect to their natural abundances could improve the interpretation of the steroid profile in doping analysis. Copyright 2009 Elsevier Inc. All rights reserved.

Spray Gun With Constant Mixing Ratio

NASA Technical Reports Server (NTRS)

Simpson, William G.

1987-01-01

Conceptual mechanism mounted in handle of spray gun maintains constant ratio between volumetric flow rates in two channels leading to spray head. With mechanism, possible to keep flow ratio near 1:1 (or another desired ratio) over range of temperatures, orifice or channel sizes, or clogging conditions.

The relationship between the plasma concentration of blonanserin, and its plasma anti-serotonin 5-HT(2A) activity/anti-dopamine D₂ activity ratio and drug-induced extrapyramidal symptoms.

PubMed

Suzuki, Hidenobu; Gen, Keishi

2012-03-01

 Blonanserin is a second-generation antipsychotic that was developed in Japan. We investigated the relationships between plasma concentration, the plasma anti-5-HT(2A) activity/anti-D₂ activity (S/D) ratio and extrapyramidal symptoms (EPS) in blonanserin dosing.  The subjects were 29 outpatients with schizophrenia. We assessed EPS using the Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). The plasma concentrations were measured by high performance liquid chromatography, and the plasma anti-D₂ and anti-5-HT(2A) activities were measured by [³H]-spiperone and [³H]-ketanserin radioreceptor assays. The results revealed that there were significant correlations between both the plasma concentration and the DIEPSS total score (P<0.05). A negative correlative tendency was found between the S/D ratio and the DIEPSS total score. Furthermore, the plasma concentrations were divided into a low plasma concentration group and a high plasma concentration group, and the S/D ratios were divided into a low S/D ratio group and a high S/D ratio group. We then compared each group based on the DIEPSS total scores. The score in the high plasma concentration-low S/D ratio group was significantly higher than in the high plasma concentration-high S/D ratio, low plasma concentration-high S/D ratio and low plasma concentration-low S/D ratio groups (P<0.05 for all).  These findings indicate that the incidence of EPS during treatment with blonanserin is mainly determined by plasma concentration, but the incidence of EPS may be inhibited when anti-5HT(2A) activity is predominant over anti-D₂ activity. © 2012 The Authors. Psychiatry and Clinical Neurosciences © 2012 Japanese Society of Psychiatry and Neurology.

Radioactive anomaly discrimination from spectral ratios

DOEpatents

Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements

2013-08-20

A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.

Labor Supply and Consumption of Food in a Closed Economy under a Range of Fixed- and Random-Ratio Schedules: Tests of Unit Price

ERIC Educational Resources Information Center

Madden, Gregory J.; Dake, Jamie M.; Mauel, Ellie C.; Rowe, Ryan R.

2005-01-01

The behavioral economic concept of unit price predicts that consumption and response output (labor supply) are determined by the unit price at which a good is available regardless of the value of the cost and benefit components of the unit price ratio. Experiment 1 assessed 4 pigeons' consumption and response output at a range of unit prices. In…

Free-ranging domestic cats (Felis catus) on public lands: estimating density, activity, and diet in the Florida Keys

USGS Publications Warehouse

Cove, Michael V.; Gardner, Beth; Simons, Theodore R.; Kays, Roland; O'Connell, Allan F.

2017-01-01

Feral and free-ranging domestic cats (Felis catus) can have strong negative effects on small mammals and birds, particularly in island ecosystems. We deployed camera traps to study free-ranging cats in national wildlife refuges and state parks on Big Pine Key and Key Largo in the Florida Keys, USA, and used spatial capture–recapture models to estimate cat abundance, movement, and activities. We also used stable isotope analyses to examine the diet of cats captured on public lands. Top population models separated cats based on differences in movement and detection with three and two latent groups on Big Pine Key and Key Largo, respectively. We hypothesize that these latent groups represent feral, semi-feral, and indoor/outdoor house cats based on the estimated movement parameters of each group. Estimated cat densities and activity varied between the two islands, with relatively high densities (~4 cats/km2) exhibiting crepuscular diel patterns on Big Pine Key and lower densities (~1 cat/km2) exhibiting nocturnal diel patterns on Key Largo. These differences are most likely related to the higher proportion of house cats on Big Pine relative to Key Largo. Carbon and nitrogen isotope ratios from hair samples of free-ranging cats (n = 43) provided estimates of the proportion of wild and anthropogenic foods in cat diets. At the population level, cats on both islands consumed mostly anthropogenic foods (>80% of the diet), but eight individuals were effective predators of wildlife (>50% of the diet). We provide evidence that cat groups within a population move different distances, exhibit different activity patterns, and that individuals consume wildlife at different rates, which all have implications for managing this invasive predator.

Exploring the CO/CN line ratio in nearby galaxies with the ALMA archive

NASA Astrophysics Data System (ADS)

Wilson, Christine D.

2018-07-01

We describe an archival project using Cycle 0 data from the Atacama Large Millimeter/submillimeter Array to survey the CO/CN line ratio in 17 nearby galaxies. CN is an interesting molecule that traces dense gas exposed to ultraviolet radiation and its N = 1 - 0 lines can be observed simultaneously with the CO J = 1 - 0 line. We identify eight galaxies with distances <200 Mpc for which both lines are detected. Signal-to-noise ratio matched CO/CN ratios range from as low as 7 to as high as 65, while ratios using the total detected flux range from 20 to 140. Spatial variations greater than a factor of 3 are seen in several galaxies. These line ratio changes are likely due to changes in the [CN]/[H2] abundance ratio and/or the CN excitation. Additional measurements of the warm gas pressure and the CN excitation should help to distinguish between these two possibilities. Three of the four active galactic nuclei in our sample show CO/CN line ratios that are roughly a factor of 2-3 larger than those seen in starburst-dominated regions, which may be in conflict with models of molecular abundances in X-ray-dominated regions.

Results of an Advanced Fan Stage Operating Over a Wide Range of Speed and Bypass Ratio. Part 1; Fan Stage Design and Experimental Results

NASA Technical Reports Server (NTRS)

Suder, Kenneth L.; Prahst, Patricia S.; Thorp, Scott A.

2011-01-01

NASA s Fundamental Aeronautics Program is investigating turbine-based combined cycle (TBCC) propulsion systems for access to space because it provides the potential for aircraft-like, space-launch operations that may significantly reduce launch costs and improve safety. To this end, National Aeronautics and Space Administration (NASA) and General Electric (GE) teamed to design a Mach 4 variable cycle turbofan/ramjet engine for access to space. To enable the wide operating range of a Mach 4+ variable cycle turbofan ramjet required the development of a unique fan stage design capable of multi-point operation to accommodate variations in bypass ratio (10 ), fan speed (7 ), inlet mass flow (3.5 ), inlet pressure (8 ), and inlet temperature (3 ). In this paper, NASA has set out to characterize a TBCC engine fan stage aerodynamic performance and stability limits over a wide operating range including power-on and hypersonic-unique "windmill" operation. Herein, we will present the fan stage design, and the experimental test results of the fan stage operating from 15 to 100 percent corrected design speed. Whereas, in the companion paper, we will provide an assessment of NASA s APNASA code s ability to predict the fan stage performance and operability over a wide range of speed and bypass ratio.

Management Ratios 1. For Colleges & Universities.

ERIC Educational Resources Information Center

Minter, John, Ed.

Ratios that enable colleges and universities to select other institutions for comparison are presented. The ratios and underlying data also enable colleges to rank order institutions and to calculate means, quartiles, and ranges for these groups. The data are based on FY 1983 U.S. Department of Education Statistics. The ratios summarize the…

Research on range-gated laser active imaging seeker

NASA Astrophysics Data System (ADS)

You, Mu; Wang, PengHui; Tan, DongJie

2013-09-01

Compared with other imaging methods such as millimeter wave imaging, infrared imaging and visible light imaging, laser imaging provides both a 2-D array of reflected intensity data as well as 2-D array of range data, which is the most important data for use in autonomous target acquisition .In terms of application, it can be widely used in military fields such as radar, guidance and fuse. In this paper, we present a laser active imaging seeker system based on range-gated laser transmitter and sensor technology .The seeker system presented here consist of two important part, one is laser image system, which uses a negative lens to diverge the light from a pulse laser to flood illuminate a target, return light is collected by a camera lens, each laser pulse triggers the camera delay and shutter. The other is stabilization gimbals, which is designed to be a rotatable structure both in azimuth and elevation angles. The laser image system consists of transmitter and receiver. The transmitter is based on diode pumped solid-state lasers that are passively Q-switched at 532nm wavelength. A visible wavelength was chosen because the receiver uses a Gen III image intensifier tube with a spectral sensitivity limited to wavelengths less than 900nm.The receiver is image intensifier tube's micro channel plate coupled into high sensitivity charge coupled device camera. The image has been taken at range over one kilometer and can be taken at much longer range in better weather. Image frame frequency can be changed according to requirement of guidance with modifiable range gate, The instantaneous field of views of the system was found to be 2×2 deg. Since completion of system integration, the seeker system has gone through a series of tests both in the lab and in the outdoor field. Two different kinds of buildings have been chosen as target, which is located at range from 200m up to 1000m.To simulate dynamic process of range change between missile and target, the seeker system has

Serum biochemistry of captive and free-ranging gray wolves (Canis lupus)

USGS Publications Warehouse

Constable, Peter; Hinchcliff, Ken; Demma, Nick; Callahan, Margaret; Dale, B.W.; Fox, Kevin; Adams, Layne G.; Wack, Ray; Kramer, Lynn

1998-01-01

Normal serum biochemistry values are frequently obtained from studies of captive sedentary (zoo) or free-ranging (wild) animals. It is frequently assumed that values from these two populations are directly referable to each other. We tested this assumption using 20 captive gray wolves (Canis lupus) in Minnesota, USA, and 11 free-ranging gray wolves in Alaska, USA. Free-ranging wolves had significantly (P<0.05) lower sodium, chloride, and creatine concentrations and significantly higher potassium and blood urea nitrogen (BUN) concentrations; BUN to creatine ratios; and alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities relative to captive wolves. Corticosteroid-induced alkaline phosphatase activity (a marker of stress in domestic dogs) was detected in 3 of 11 free-ranging wolves and in 0 of 20 captive wolves (P = 0.037). This study provides clear evidence that serum biochemical differences can exist between captive and free-ranging populations of one species. Accordingly, evaluation of the health status of an animal should incorporate an understanding of the potential confounding effect that nutrition, activity level, and environmental stress could have on the factor(s) being measured.

Cardiothoracic ratio within the “normal” range independently predicts mortality in patients undergoing coronary angiography

PubMed Central

Zaman, M Justin S; Sanders, Julie; Crook, Angela M; Feder, Gene; Shipley, Martin; Timmis, Adam; Hemingway, Harry

2007-01-01

Objective To determine whether cardiothoracic ratio (CTR), within the range conventionally considered normal, predicted prognosis in patients undergoing coronary angiography. Design Cohort study with a median of 7‐years follow‐up. Setting Consecutive patients undergoing coronary angiography at Barts and The London National Health Service (NHS) Trust. Subjects 1005 patients with CTRs measured by chest radiography, and who subsequently underwent coronary angiography. Of these patients, 7.3% had a CTR ⩾0.5 and were excluded from the analyses. Outcomes All‐cause mortality and coronary event (non‐fatal myocardial infarction or coronary death). Adjustments were made for age, left ventricular dysfunction, ACE inhibitor treatment, body mass index, number of diseased coronary vessels and past coronary artery bypass graft. Results The risk of death was increased among patients with a CTR in the upper part of the normal range. In total, 94 (18.9%) of those with a CTR below the median of 0.42 died compared with 120 (27.8%) of those with a CTR between 0.42 and 0.49 (log rank test p<0.001). After adjusting for potential confounders, this increased risk remained (adjusted HR 1.45, 95% CI 1.03 to 2.05). CTR, at values below 0.5, was linearly related to the risk of coronary event (test for trend p = 0.024). Conclusion : In patients undergoing coronary angiography, CTR between 0.42 and 0.49 was associated with higher mortality than in patients with smaller hearts. There was evidence of a continuous increase in risk with higher CTR. These findings, along with those in healthy populations, question the conventional textbook cut‐off point of ⩾0.5 being an abnormal CTR. PMID:17164481

Protein/energy ratios of current diets in developed and developing countries compared with a safe protein/energy ratio: implications for recommended protein and amino acid intakes.

PubMed

Millward, D Joe; Jackson, Alan A

2004-05-01

Revised estimates of protein and amino acid requirements are under discussion by the Food and Agriculture Organization (FAO)/World Health Organizaion (WHO), and have been proposed in a recent report on Dietary Reference Intakes (DRIs) from the USA. The nature and magnitude of these requirements are not entirely resolved, and no consideration has been given to the potential influence of metabolic adaptation on dietary requirements. We have examined the implications of these new values, and of the conceptual metabolic framework in which they are used, for defining the nutritional adequacy of protein intakes in developed and developing countries. We have expressed proposed values for protein requirements in relation to energy requirements, predicted for physical activity levels of 1.5, 1.75 and 2.0 times basal metabolic rate, in order to generate reference ratios for protein energy/total energy (reference P/E ratio) as a function of age, body weight, gender and physical activity level. Proposed values for amino acid requirements have been used to adjust the available digestible P/E ratio of foods and diets for protein quality. Focusing on the diets of UK omnivores and vegetarians and on diets in India, the risk of protein deficiency is evaluated from a comparison of P/E ratios of metabolic requirements with protein-quality-adjusted P/E ratios of intakes. A qualitative and conservative estimate of risk of deficiency is made by comparing the adjusted P/E ratio of the intake with a reference P/E ratio calculated for age, body weight, gender and physical activity according to FAO/WHO/United Nations University. A semi-quantitative estimate of risk of deficiency has also been made by the cut point approach, calculated as the proportion of the intake distribution below the mean P/E ratio of the requirement. Values for the quality-adjusted P/E ratio of the diet range from 0.126 for the UK omnivore diet to 0.054 for a rice-based diet of adults in West Bengal, which is lysine

Climate dominated topography in a tectonically active mountain range

NASA Astrophysics Data System (ADS)

Adams, B. A.; Ehlers, T. A.

2015-12-01

Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The broad spatial trend in channel steepness values suggests that the locus of high rock uplift rates is coincident with the rugged range core, in a similar position as high temperature and pressure lithologies, but not in the low lying foothills as has been previously suggested by low-temperature thermochronometry. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns. We demonstrate the same topographic effects are recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on topography makes the argument of mountain range steadiness untenable in significantly glaciated settings. Furthermore, our results suggest that most glaciated Cenozoic ranges are likely still in a mode of readjustment as fluvial systems change topography and erosion rates to equilibrate with rock uplift rates.

Development of acoustically lined ejector technology for multitube jet noise suppressor nozzles by model and engine tests over a wide range of jet pressure ratios and temperatures

NASA Technical Reports Server (NTRS)

Atvars, J.; Paynter, G. C.; Walker, D. Q.; Wintermeyer, C. F.

1974-01-01

An experimental program comprising model nozzle and full-scale engine tests was undertaken to acquire parametric data for acoustically lined ejectors applied to primary jet noise suppression. Ejector lining design technology and acoustical scaling of lined ejector configurations were the major objectives. Ground static tests were run with a J-75 turbojet engine fitted with a 37-tube, area ratio 3.3 suppressor nozzle and two lengths of ejector shroud (L/D = 1 and 2). Seven ejector lining configurations were tested over the engine pressure ratio range of 1.40 to 2.40 with corresponding jet velocities between 305 and 610 M/sec. One-fourth scale model nozzles were tested over a pressure ratio range of 1.40 to 4.0 with jet total temperatures between ambient and 1088 K. Scaling of multielement nozzle ejector configurations was also studied using a single element of the nozzle array with identical ejector lengths and lining materials. Acoustic far field and near field data together with nozzle thrust performance and jet aerodynamic flow profiles are presented.

NREL to Host Range of Activities for Energy Awareness Month

Science.gov Websites

Host Range of Activities for Energy Awareness Month Events devoted to energy savings Golden, Colo., Sept. 20, 2000 - Visitors will get an inside look at advanced energy technologies and learn tips for cutting utility bills when the U.S. Department of Energy's National Renewable Energy

Active and Inactive Enhancers Cooperate to Exert Localized and Long-Range Control of Gene Regulation.

PubMed

Proudhon, Charlotte; Snetkova, Valentina; Raviram, Ramya; Lobry, Camille; Badri, Sana; Jiang, Tingting; Hao, Bingtao; Trimarchi, Thomas; Kluger, Yuval; Aifantis, Iannis; Bonneau, Richard; Skok, Jane A

2016-06-07

V(D)J recombination relies on the presence of proximal enhancers that activate the antigen receptor (AgR) loci in a lineage- and stage-specific manner. Unexpectedly, we find that both active and inactive AgR enhancers cooperate to disseminate their effects in a localized and long-range manner. Here, we demonstrate the importance of short-range contacts between active enhancers that constitute an Igk super-enhancer in B cells. Deletion of one element reduces the interaction frequency between other enhancers in the hub, which compromises the transcriptional output of each component. Furthermore, we establish that, in T cells, long-range contact and cooperation between the inactive Igk enhancer MiEκ and the active Tcrb enhancer Eβ alters enrichment of CBFβ binding in a manner that impacts Tcrb recombination. These findings underline the complexities of enhancer regulation and point to a role for localized and long-range enhancer-sharing between active and inactive elements in lineage- and stage-specific control. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

An all-solid-state microsecond-range quasi-square pulse generator based on fractional-turn ratio saturable pulse transformer and anti-resonance network.

PubMed

Chen, Rong; Yang, Jianhua; Cheng, Xinbing; Pan, Zilong

2017-03-01

High voltage pulse generators are widely applied in a number of fields. Defense and industrial applications stimulated intense interests in the area of pulsed power technology towards the system with high power, high repetition rate, solid state characteristics, and compact structure. An all-solid-state microsecond-range quasi-square pulse generator based on a fractional-turn ratio saturable pulse transformer and anti-resonance network is proposed in this paper. This generator consists of a charging system, a step-up system, and a modulating system. In this generator, the fractional-turn ratio saturable pulse transformer is the key component since it acts as a step-up transformer and a main switch during the working process. Demonstrative experiments show that if the primary storage capacitors are charged to 400 V, a quasi-square pulse with amplitude of about 29 kV can be achieved on a 3500 Ω resistive load, as well as the pulse duration (full width at half maximum) of about 1.3 μs. Preliminary repetition rate experiments are also carried out, which indicate that this pulse generator could work stably with the repetition rates of 30 Hz and 50 Hz. It can be concluded that this kind of all-solid-state microsecond-range quasi-square pulse generator can not only lower both the operating voltage of the primary windings and the saturable inductance of the secondary windings, thus ideally realizing the magnetic switch function of the fractional-turn ratio saturable pulse transformer, but also achieve a quasi-square pulse with high quality and fixed flat top after the modulation of a two-section anti-resonance network. This generator can be applied in areas of large power microwave sources, sterilization, disinfection, and wastewater treatment.

Long-range dismount activity classification: LODAC

NASA Astrophysics Data System (ADS)

Garagic, Denis; Peskoe, Jacob; Liu, Fang; Cuevas, Manuel; Freeman, Andrew M.; Rhodes, Bradley J.

2014-06-01

Continuous classification of dismount types (including gender, age, ethnicity) and their activities (such as walking, running) evolving over space and time is challenging. Limited sensor resolution (often exacerbated as a function of platform standoff distance) and clutter from shadows in dense target environments, unfavorable environmental conditions, and the normal properties of real data all contribute to the challenge. The unique and innovative aspect of our approach is a synthesis of multimodal signal processing with incremental non-parametric, hierarchical Bayesian machine learning methods to create a new kind of target classification architecture. This architecture is designed from the ground up to optimally exploit correlations among the multiple sensing modalities (multimodal data fusion) and rapidly and continuously learns (online self-tuning) patterns of distinct classes of dismounts given little a priori information. This increases classification performance in the presence of challenges posed by anti-access/area denial (A2/AD) sensing. To fuse multimodal features, Long-range Dismount Activity Classification (LODAC) develops a novel statistical information theoretic approach for multimodal data fusion that jointly models multimodal data (i.e., a probabilistic model for cross-modal signal generation) and discovers the critical cross-modal correlations by identifying components (features) with maximal mutual information (MI) which is efficiently estimated using non-parametric entropy models. LODAC develops a generic probabilistic pattern learning and classification framework based on a new class of hierarchical Bayesian learning algorithms for efficiently discovering recurring patterns (classes of dismounts) in multiple simultaneous time series (sensor modalities) at multiple levels of feature granularity.

Spherical gearing with intermediate ball elements: parameter ranges with a high contact ratio

NASA Astrophysics Data System (ADS)

Gorbenko, M. V.; Gorbenko, T. I.

2017-02-01

The paper presents analytical research of the geometry and kinematical parameters of spherical gearing with ball intermediate elements. The main attention is paid to the influence of the offset coefficient on the tooth geometry generation, the contact ratio and the motion transmission angle. Intermediate ball element racetracks on the gear are trochoidal curves on a spherical surface. Two areas for the offset coefficient values providing a high value of the contact ratio - basic trochoid (without offset) and prolate trochoid with abutting racetracks of adjacent ball elements ― were revealed. Analysis of the investigated parameters showed that for power transmission, it is preferable to use spherical gearing without an offset, and for kinematic transmission, it is possible to use profiles with a large offset. The present study allows making a rational choice of geometrical parameters depending on the transmission predestination.

The relationship between physical activity and 2-hydroxyestrone, 16alpha-hydroxyestrone, and the 2/16 ratio in premenopausal women (United States).

PubMed

Bentz, Ann T; Schneider, Carole M; Westerlind, Kim C

2005-05-01

Estrogen is metabolized in the body through two mutually exclusive pathways yielding metabolites with different biological activities: the low estrogenic 2-hydroxyestrone (2-OHE1) and the highly estrogenic 16alpha-hydroxyestrone (16alpha-OHE1). The ratio of these metabolites (2/16) may be predictive of risk for developing breast cancer. Early evidence has demonstrated that exercise may alter estrogen metabolism to favor the weak estrogen, 2-OHE1. Seventy-seven eumenorrheic females completed physical activity logs for two weeks prior to providing a luteal phase urine sample. Concentrations of 2-OHE1 and 16alpha-OHE1 were measured and the 2/16 ratio computed. Hierarchical regression, controlling for age and body mass index (BMI), was used to determine relationships between estrogen metabolites and daily physical activity. Regression analyses indicated significant positive relationships between physical activity and 2-OHE1 and the 2/16 ratio (p < 0.05) that appears to be independent of BMI. 16alpha-OHE1 was not significantly related to physical activity. These results indicate that physical activity may modulate estrogen metabolism to favor the weak estrogen, 2-OHE1, thus producing a higher 2/16 ratio. This alteration in estrogen metabolism may represent one of the mechanisms by which increased physical activity reduces breast cancer risk.

High ratio of T790M to EGFR activating mutations correlate with the osimertinib response in non-small-cell lung cancer.

PubMed

Ariyasu, Ryo; Nishikawa, Shingo; Uchibori, Ken; Oh-Hara, Tomoko; Yoshizawa, Takahiro; Dotsu, Yosuke; Koyama, Junji; Saiki, Masafumi; Sonoda, Tomoaki; Kitazono, Satoru; Yanagitani, Noriko; Horiike, Atsushi; Inase, Naohiko; Kasahara, Kazuo; Nishio, Makoto; Katayama, Ryohei

2018-03-01

Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that can overcome resistance due to the Thr790Met (T790M) mutation. However, osimertinib occasionally shows limited efficacy in a small population of patients. We investigated the correlation between the ratio of T790M to EGFR activating mutation and the response to osimertinib. Between April 2016 and April 2017, 44 patients started osimertinib therapy at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research. We performed EGFR mutation analysis of cytological samples from 33 patients using droplet digital PCR. We calculated the ratio of T790M to EGFR activating mutations and correlated it with the systemic response to osimertinib. In tumors from the 33 patients, the average ratio of T790M to EGFR activating mutations was 0.420. Twenty-one of the 33 patients had tumors with a T790M ratio of ≥0.4. The osimertinib response rate was significantly higher (92.3%) in patients with a T790M ratio of ≥0.4 than in those with a T790M ratio of <0.4 (52.6%; p = 0.0237). We examined the correlation between the T790M ratio and the tumor reduction rate and obtained a coefficient of r = 0.417 (p = 0.0175). In patients with a T790M ratio of ≥0.4, the median progression-free survival was 355 days, which was longer, but not significant, than that in patients with a T790M ratio of <0.4 (median: 264 days). In patients with a T790M ratio of ≥0.4, the median treatment duration from first-line therapy onward was 931 days, which was significantly longer than that in patients with a T790M ratio of <0.4 (median, 567.5 days) (p = 0.044). The T790M ratio to EGFR activating mutation in tumor may correlate with the response to osimertinib, and patients with a higher T790M ratio have a longer treatment history. Copyright © 2017 Elsevier B.V. All rights reserved.

Neutron activation measurements over an extremely wide dynamic range (invited) (abstract)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnes, C.W.

1997-01-01

The DT program at the Tokamak Fusion Test Reactor (TFTR) created requirements on 14 MeV neutron measurements to measure from 10{sup 6} n/cm{sup 2} (for triton burnup and Ohmic tritium plasmas) to {gt}10{sup 12} n/cm{sup 2} (characteristic of {gt}10 MW DT plasmas) with an accuracy of 7% (one-sigma).1 To maintain an absolute calibration over this dynamic range with active neutron detectors required one to go from some absolute standard at one fluence level to a measurement at a much higher fluence. Maintaining accuracy requires an extremely linear set of measurements not systematically affected over this dynamic range. Neutron activation canmore » provide such linearity when care is taken with a number of effects such as gamma-ray detection efficiency and sample contamination.2 Absolutely calibrated neutron yield measurements using dosimetric (well-known cross section) reactions with thin (low-mass) elemental foils is be described. This technique makes the detector comparison to an absolute standard of gamma-ray activity correspond to all neutron fluences by reducing the sample mass while keeping the activation detectors operating in a linear counting mode; i.e., low count rates which minimize pileup effects. The International Thermonuclear Experimental Reactor is projected to have 1000 s burn durations at fluxes of few 10{sup 13} n/cm{sup 2}s, or more neutron fluence {ital per second} than entire TFTR discharges. Extrapolating neutron activation to these higher fluences will require yet more care. Some of the issues at such high fluences will be discussed.3 The National Ignition Facility (NIF) is projected to yield 10 MJ of fusion energy, or up to 10{sup 12} n/cm{sup 2} at the vacuum vessel wall, similar to TFTR DT conditions. It is expected that much interesting physics will be performed at yields far less than those from ignition, covering an even greater dynamic range than needed on TFTR. Thin foil techniques do not have the sensitivity required at low fluences.« less

Comprehensive analysis of proton range uncertainties related to stopping-power-ratio estimation using dual-energy CT imaging

NASA Astrophysics Data System (ADS)

Li, B.; Lee, H. C.; Duan, X.; Shen, C.; Zhou, L.; Jia, X.; Yang, M.

2017-09-01

The dual-energy CT-based (DECT) approach holds promise in reducing the overall uncertainty in proton stopping-power-ratio (SPR) estimation as compared to the conventional stoichiometric calibration approach. The objective of this study was to analyze the factors contributing to uncertainty in SPR estimation using the DECT-based approach and to derive a comprehensive estimate of the range uncertainty associated with SPR estimation in treatment planning. Two state-of-the-art DECT-based methods were selected and implemented on a Siemens SOMATOM Force DECT scanner. The uncertainties were first divided into five independent categories. The uncertainty associated with each category was estimated for lung, soft and bone tissues separately. A single composite uncertainty estimate was eventually determined for three tumor sites (lung, prostate and head-and-neck) by weighting the relative proportion of each tissue group for that specific site. The uncertainties associated with the two selected DECT methods were found to be similar, therefore the following results applied to both methods. The overall uncertainty (1σ) in SPR estimation with the DECT-based approach was estimated to be 3.8%, 1.2% and 2.0% for lung, soft and bone tissues, respectively. The dominant factor contributing to uncertainty in the DECT approach was the imaging uncertainties, followed by the DECT modeling uncertainties. Our study showed that the DECT approach can reduce the overall range uncertainty to approximately 2.2% (2σ) in clinical scenarios, in contrast to the previously reported 1%.

Active and inactive enhancers co-operate to exert localized and long-range control of gene regulation

PubMed Central

Proudhon, Charlotte; Snetkova, Valentina; Raviram, Ramya; Lobry, Camille; Badri, Sana; Jiang, Tingting; Hao, Bingtao; Trimarchi, Thomas; Kluger, Yuval; Aifantis, Iannis; Bonneau, Richard; Skok, Jane A

2016-01-01

V(D)J recombination relies on the presence of proximal enhancers that activate the antigen receptor (AgR) loci in a lineage and stage specific manner. Unexpectedly we find that both active and inactive AgR enhancers co-operate to disseminate their effects in a localized and long-range manner. Here we demonstrate the importance of short-range contacts between active enhancers that constitute an Igk super-enhancer in B cells. Deletion of one element reduces the interaction frequency between other enhancers in the hub, which compromises the transcriptional output of each component. We further establish that in T cells long-range contact and co-operation between the inactive Igk enhancer, MiEκ and the active Tcrb enhancer, Eβ, alters enrichment of CBFβ binding in a manner that impacts Tcrb recombination. These findings underline the complexities of enhancer regulation and point to a role for localized and long-range enhancer-sharing between active and inactive elements in lineage and stage specific control. PMID:27239026

Knee strength ratios in competitive female athletes

PubMed Central

Murawa, Michal; Mackala, Krzysztof; Dworak, Lechoslaw Bogdan

2018-01-01

Knee strength ratios are related to the movement patterns, sport-specific training and knee injuries in athletes. The purpose of this study was to determine the ratios in the concentric isokinetic strength of the hamstrings and quadriceps and the isometric strength of the knee extensors. In female basketball players (n = 14) and female volleyball players (n = 12) were evaluated: the hamstrings to quadriceps peak torque ratio (H/Q) and side-to-side peak torque ratio (TR) for hamstrings and quadriceps; the ratio of the maximal bilateral strength to the summed maximal unilateral strength (B/U) and side-to-side maximal strength ratio (SR) for knee extensors. For the H/Q values, a 2 × 2 × 3 mixed-factorial analysis of variance and Bonferroni post hoc test were computed. The H/Q values increased from 48.0 (3.9)% at 60°/s to 70.4 (7.9)% at 300°/s. Furthermore, there were significant differences in the H/Q values between 300°/s and 180°/s, 300°/s and 60°/s in basketball and volleyball athletes, and between 180°/s and 60°/s only in basketball athletes (p < .05). Significantly higher H/Q results at 60°/s demonstrated basketball players than volleyball players (p < .05). Differences in the TR and SR mean values ranged from 4.4% to 8.6% and indicated no significant side-to-side strength deficits (p > .05). In both groups, greater isometric strength developed bilaterally was found (B/U > 100%). The findings revealed the magnitude of knee strength ratios in female athletes determined by sport-specific movements in basketball and volleyball. This study highlighted the importance of the bilateral strength deficit and muscular balance between the hamstrings and quadriceps in basketball and volleyball athletes in activities related to their movement patterns and specific training. PMID:29315348

Effect of contact ratio on spur gear dynamic load

NASA Technical Reports Server (NTRS)

Liou, Chuen-Huei; Lin, Hsiang Hsi; Oswald, Fred B.; Townsend, Dennis P.

1992-01-01

A computer simulation is presented which shows how the gear contact ratio affects the dynamic load on a spur gear transmission. The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance. The analysis presented was performed using the NASA gear dynamics code, DANST. In the analysis, the contact ratio was varied over the range 1.20 to 2.40 by changing the length of the tooth addendum. In order to simplify the analysis, other parameters related to contact ratio were held constant. The contact ratio was found to have a significant influence on gear dynamics. Over a wide range of operating speeds, a contact ratio close to 2.0 minimized dynamic load. For low contact ratio gears (contact ratio less than 2.0), increasing the contact ratio reduced the gear dynamic load. For high contact ratio gears (contact ratio = or greater than 2.0), the selection of contact ratio should take into consideration the intended operating speeds. In general, high contact ratio gears minimized dynamic load better than low contact ratio gears.

A study on muscle activity and ratio of the knee extensor depending on the types of squat exercise

PubMed Central

Kang, Jeong-Il; Park, Joon-Su; Choi, Hyun; Jeong, Dae-Keun; Kwon, Hye-Min; Moon, Young-Jun

2017-01-01

[Purpose] For preventing the patellofemoral pain syndrome, this study aims to suggest a proper squat method, which presents selective muscle activity of Vastus Medialis Oblique and muscle activity ratios of Vastus Medialis Oblique/Vastus Lateralis by applying squat that is a representative weight bearing exercise method in various ways depending on the surface conditions and knee bending angles. [Subjects and Methods] An isometric squat that was accompanied by hip adduction, depending on the surface condition and the knee joint flexion angle, was performed by 24 healthy students. The muscle activity and the ratio of muscle activity were measured. [Results] In a comparison of muscle activity depending on the knee joint flexion angle on a weight-bearing surface, the vastus medialis oblique showed a significant difference at 15° and 60°. Meanwhile, in a comparison of the muscle activity ratio between the vastus medialis oblique and the vastus lateralis depending on the knee joint flexion angle on a weight-bearing surface, significant differences were observed at 15° and 60°. [Conclusion] An efficient squat exercise posture for preventing the patellofemoral pain syndrome is to increase the knee joint bending angle on a stable surface. But it would be efficient for patients with difficulties in bending the knee joint to keep a knee joint bending angle of 15 degrees or less on an unstable surface. It is considered that in future, diverse studies on selective Vastus Medialis Oblique strengthening exercise methods would be needed after applying them to patients with the patellofemoral pain syndrome. PMID:28210036

Molecular hydrogen in the vicinity of NGC 7538 IRS 1 and IRS 2 - Temperature and ortho-to-para ratio

NASA Technical Reports Server (NTRS)

Hoban, Susan; Reuter, Dennis C.; Mumma, Michael J.; Storrs, Alex D.

1991-01-01

Near-infrared spectroscopic observations of the active star-forming region near NGC 7538 IRS 1 and IRS 2 were made. The relative intensities of the v = 1-0 Q(1), Q(3), and Q(5) lines of molecular hydrogen are used to calculate a rotational excitation temperature. Comparison of the measured intensity of the Q(2) transition relative to the intensity of Q(1) and Q(3) permitted the retrieval of the ratio of ortho-to-para hydrogen. It is found that an ortho-to-para ratio of between 1.6 and 2.35 is needed to explain the Q-branch line intensity ratios, depending on the excitation model used. This range in ortho-to-para ratios implies a range of molecular hydrogen formation temperature of approximately 105 K to 140 K.

Elevated sacroilac joint uptake ratios in systemic lupus erythematosus

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Smet, A.A.; Mahmood, T.; Robinson, R.G.

1984-08-01

Sacroiliac joint radiographs and radionuclide sacroiliac joint uptake ratios were obtained on 14 patients with active systemic lupus erythematosus. Elevated joint ratios were found unilaterally in two patients and bilaterally in seven patients when their lupus was active. In patients whose disease became quiescent, the uptake ratios returned to normal. Two patients had persistently elevated ratios with continued clinical and laboratory evidence of active lupus. Mild sacroiliac joint sclerosis and erosions were detected on pelvic radiographs in these same two patients. Elevated quantitative sacroiliac joint uptake ratios may occur as a manifestation of active systemic lupus erythematosus.

Emergent ultra–long-range interactions between active particles in hybrid active–inactive systems

PubMed Central

Steimel, Joshua P.; Aragones, Juan L.; Hu, Helen; Qureshi, Naser; Alexander-Katz, Alfredo

2016-01-01

Particle–particle interactions determine the state of a system. Control over the range of such interactions as well as their magnitude has been an active area of research for decades due to the fundamental challenges it poses in science and technology. Very recently, effective interactions between active particles have gathered much attention as they can lead to out-of-equilibrium cooperative states such as flocking. Inspired by nature, where active living cells coexist with lifeless objects and structures, here we study the effective interactions that appear in systems composed of active and passive mixtures of colloids. Our systems are 2D colloidal monolayers composed primarily of passive (inactive) colloids, and a very small fraction of active (spinning) ferromagnetic colloids. We find an emergent ultra–long-range attractive interaction induced by the activity of the spinning particles and mediated by the elasticity of the passive medium. Interestingly, the appearance of such interaction depends on the spinning protocol and has a minimum actuation timescale below which no attraction is observed. Overall, these results clearly show that, in the presence of elastic components, active particles can interact across very long distances without any chemical modification of the environment. Such a mechanism might potentially be important for some biological systems and can be harnessed for newer developments in synthetic active soft materials. PMID:27071096

ESA activities on satellite laser ranging to non-cooperative objects

NASA Astrophysics Data System (ADS)

Flohrer, Tim; Krag, Holger; Funke, Quirin; Jilete, Beatriz; Mancas, Alexandru

2016-07-01

Satellite laser ranging (SLR) to non-cooperative objects is an emerging technology that can contribute significantly to operational, modelling and mitigation needs set by the space debris population. ESA is conducting various research and development activities in SLR to non-cooperative objects. ESA's Space Situational Awareness (SSA) program supports specific activities in the Space Surveillance and Tracking (SST) segment. Research and development activities with operational aspects are run by ESA's Space Debris Office. At ESA SSA/SST comprises detecting, cataloguing and predicting the objects orbiting the Earth, and the derived applications. SST aims at facilitating research and development of sensor and data processing technologies and of related common components while staying complementary with, and in support of, national and multi-national European initiatives. SST promotes standardisation and interoperability of the technology developments. For SLR these goals are implemented through researching, developing, and deploying an expert centre. This centre shall coordinate the contribution of system-external loosely connected SLR sensors, and shall provide back calibration and expert evaluation support to the sensors. The Space Debris Office at ESA is responsible for all aspects related to space debris in the Agency. It is in charge of providing operational support to ESA and third party missions. Currently, the office studies the potential benefits of laser ranging to space debris objects to resolve close approaches to active satellites, to improve re-entry predictions of time and locations, and the more general SLR support during contingency situations. The office studies the determination of attitude and attitude motion of uncooperative objects with special focus on the combination of SLR, light-curve, and radar imaging data. Generating sufficiently precise information to allow for the acquisition of debris objects by a SLR sensor in a stare

Bone mineral density across a range of physical activity volumes: NHANES 2007-2010.

PubMed

Whitfield, Geoffrey P; Kohrt, Wendy M; Pettee Gabriel, Kelley K; Rahbar, Mohammad H; Kohl, Harold W

2015-02-01

The association between aerobic physical activity volume and bone mineral density (BMD) is not completely understood. The purpose of this study was to clarify the association between BMD and aerobic activity across a broad range of activity volumes, particularly volumes between those recommended in the 2008 Physical Activity Guidelines for Americans and those of trained endurance athletes. Data from the 2007-2010 National Health and Nutrition Examination Survey were used to quantify the association between reported physical activity and BMD at the lumbar spine and proximal femur across the entire range of activity volumes reported by US adults. Participants were categorized into multiples of the minimum guideline-recommended volume based on reported moderate- and vigorous-intensity leisure activity. Lumbar and proximal femur BMD were assessed with dual-energy x-ray absorptiometry. Among women, multivariable-adjusted linear regression analyses revealed no significant differences in lumbar BMD across activity categories, whereas proximal femur BMD was significantly higher among those who exceeded the guidelines by 2-4 times than those who reported no activity. Among men, multivariable-adjusted BMD at both sites neared its highest values among those who exceeded the guidelines by at least 4 times and was not progressively higher with additional activity. Logistic regression estimating the odds of low BMD generally echoed the linear regression results. The association between physical activity volume and BMD is complex. Among women, exceeding guidelines by 2-4 times may be important for maximizing BMD at the proximal femur, whereas among men, exceeding guidelines by ≥4 times may be beneficial for lumbar and proximal femur BMD.

Use of Dynamic Geometry as a Support to Paper and Pencil Activities for Comprehension of Ratio and Proportion Topics

ERIC Educational Resources Information Center

Ruiz, Elena Fabiola; Lupianez, Jose Luis

2010-01-01

Introduction: The present paper shows the importance of a joint use of pencil and paper activities and of technology so that students may develop a complete understanding of ratio and proportion. A previous experience with strategy use when solving ratio and proportion problems provided background. Prompted by a recognition of the cognitive…

A Highly Linear and Wide Input Range Four-Quadrant CMOS Analog Multiplier Using Active Feedback

NASA Astrophysics Data System (ADS)

Huang, Zhangcai; Jiang, Minglu; Inoue, Yasuaki

Analog multipliers are one of the most important building blocks in analog signal processing circuits. The performance with high linearity and wide input range is usually required for analog four-quadrant multipliers in most applications. Therefore, a highly linear and wide input range four-quadrant CMOS analog multiplier using active feedback is proposed in this paper. Firstly, a novel configuration of four-quadrant multiplier cell is presented. Its input dynamic range and linearity are improved significantly by adding two resistors compared with the conventional structure. Then based on the proposed multiplier cell configuration, a four-quadrant CMOS analog multiplier with active feedback technique is implemented by two operational amplifiers. Because of both the proposed multiplier cell and active feedback technique, the proposed multiplier achieves a much wider input range with higher linearity than conventional structures. The proposed multiplier was fabricated by a 0.6µm CMOS process. Experimental results show that the input range of the proposed multiplier can be up to 5.6Vpp with 0.159% linearity error on VX and 4.8Vpp with 0.51% linearity error on VY for ±2.5V power supply voltages, respectively.

Impact of target-to-background ratio, target size, emission scan duration, and activity on physical figures of merit for a 3D LSO-based whole body PET/CT scanner.

PubMed

Brambilla, M; Matheoud, R; Secco, C; Sacchetti, G; Comi, S; Rudoni, M; Carriero, A; Inglese, E

2007-10-01

The aim of our work is to describe the way in which physical figures of merit such as contrast-to-noise ratio (CNR) behave when varying acquisition parameters such as emission scan duration (ESD) or activity at the start of acquisition (A(acq)) that in clinical practice can be selected by the user, or object properties such as target dimensions or target-to-background (T/B) ratio, which depend uniquely on the intrinsic characteristics of the object being imaged. Figures of merit, used to characterize image quality and quantitative accuracy for a 3D-LSO based PET/CT scanner, were studied as a function of ESD and A(acq) for different target sizes and T/B ratios using a multivariate approach in a wide range of conditions approaching the ones that can be encountered in clinical practice. An annular ring of water bags of 3 cm thickness was fitted over an IEC phantom in order to obtain counting rates similar to those found in average patients. The average scatter fraction (SF) of the modified IEC phantom was similar to the mean SF measured on patients with a similar scanner. A supplemental set of micro-hollow spheres was positioned inside the phantom. The NEMA NU 2-2001 scatter phantom was positioned at the end of the IEC phantom to approximate the clinical situation of having activity that extends beyond the scanner. The phantoms were filled with a solution of water and 18F (12 kBq/mL) and the spheres with various T/B ratios of 22.5, 10.3, and 3.6. Sequential imaging was performed to acquire PET images with varying background activity concentrations of about 12, 9, 6.4, 5.3, and 3.1 kBq/mL, positioned on the linear portion of the phantom's NECR curve, well below peak NECR of 61.2 kcps that is reached at 31.8 kBq/mL. The ESD was set to 1, 2, 3, and 4 min/bed. With T/B ratios of 3.6, 10.3, and 22.5, the 13.0, 8.1, and 6.5 mm spheres were detectable for the whole ranges of background activity concentration and ESD, respectively. The ESD resulted as the most significant

Doppler and range determination for deep space vehicles using active optical transponders.

PubMed

Kinman, P W; Gagliardi, R M

1988-11-01

This paper describes and analyzes two types of laser system employing active transponders that could accurately determine Doppler and range to deep space vehicles from earth-orbiting satellites. The first is a noncoherent optical system in which the Doppler effect on an intensity-modulating subcarrier is measured. The second is a coherent optical system in which the Doppler effect of the optical carrier itself is measured. Doppler and range measurement errors are mathematically modeled and, for three example systems, numerically evaluated.

Doppler and range determination for deep space vehicles using active optical transponders

NASA Technical Reports Server (NTRS)

Kinman, Peter W.; Gagliardi, Robert M.

1988-01-01

This paper describes and analyzes two types of laser system employing active transponders that could accurately determine Doppler and range to deep space vehicles from earth-orbiting satellites. The first is a noncoherent optical system in which the Doppler effect on an intensity-modulating subcarrier is measured. The second is a coherent optical system in which the Doppler effect of the optical carrier itself is measured. Doppler and range measurement errors are mathematically modeled and, for three example systems, numerically evaluated.

Microfluidic active mixers employing ultra-high aspect-ratio rare-earth magnetic nano-composite polymer artificial cilia

NASA Astrophysics Data System (ADS)

Rahbar, Mona; Shannon, Lesley; Gray, Bonnie L.

2014-02-01

We present a new micromixer based on highly magnetic, flexible, high aspect-ratio, artificial cilia that are fabricated as individual micromixer elements or in arrays for improved mixing performance. These new cilia enable high efficiency, fast mixing in a microchamber, and are controlled by small electromagnetic fields. The artificial cilia are fabricated using a new micromolding process for nano-composite polymers. Cilia fibers with aspect-ratios as high as 8:0.13 demonstrate the fabrication technique's capability in creating ultra-high aspect-ratio microstructures. Cilia, which are realized in polydimethylsiloxane doped with rare-earth magnetic powder, are magnetized to produce permanent magnetic structures with bidirectional deflection capabilities, making them highly suitable as mixers controlled by electromagnetic fields. Due to the high magnetization level of the polarized nano-composite polymer, we are able to use miniature electromagnets providing relatively small magnetic fields of 1.1 to 7 mT to actuate the cilia microstructures over a very wide motion range. Mixing performances of a single cilium, as well as different arrays of multiple cilia ranging from 2 to 8 per reaction chamber, are characterized and compared with passive diffusion mixing performance. The mixer cilia are actuated at different amplitudes and frequencies to optimize mixing performance. We demonstrate that more than 85% of the total volume of the reaction chamber is fully mixed after 3.5 min using a single cilium mixer at 7 mT compared with only 20% of the total volume mixed with passive diffusion. The time to achieve over 85% mixing is further reduced to 70 s using an array of eight cilia microstructures. The novel microfabrication technique and use of rare-earth permanently-magnetizable nano-composite polymers in mixer applications has not been reported elsewhere by other researchers. We further demonstrate improved mixing over other cilia micromixers as enabled by the high aspect-ratio

Environmental factors associated with physician's engagement in communication activities.

PubMed

Mazurenko, Olena; Hearld, Larry R

2015-01-01

Communication between patients and providers is a crucial component of effective care coordination and is associated with a number of desired patient and provider outcomes. Despite these benefits, physician-patient and physician-physician communication occurs infrequently. The purpose of this study was to examine the relationship between a medical practice's external environment and physician engagement in communication activities. This was a cross-sectional examination of 4,299 U.S. physicians' self-reported engagement in communication activities. Communication was operationalized as physician's time spent on communication with patients and other providers during a typical work day. The explanatory variables were measures of environmental complexity, dynamism, and munificence. Data sources were the Health Tracking Physician Survey, the Area Resource File database, and the Dartmouth Atlas. Binary logistic regression was used to estimate the association between the environmental factors and physician engagement in communication activities. Several environmental factors, including per capita income (odds ratio range, 1.17-1.38), urban location (odds ratio range, 1.08-1.45), fluctuations in Health Maintenance Organization penetration (odds ratio range, 3.47-13.22), poverty (odds ratio range, 0.80-0.97) and population rates (odds ratio range, 1.01-1.02), and the presence of a malpractice crisis (odds ratio range, 0.22-0.43), were significantly associated with communication. Certain aspects of a physician's external environment are associated with different modes of communication with different recipients (patients and providers). This knowledge can be used by health care managers and policy makers who strive to improve communication between different stakeholders within the health care system (e.g., patient and providers).

CD4(+)/CD8(+) T-lymphocyte Ratio: Effects of Rehydration before Exercise in Dehydrated Men

NASA Technical Reports Server (NTRS)

Greenleaf, John E.; Jackson, Catherine G. R.; Lawless, Desales

1995-01-01

Effects of fluid ingestion on CD4+/CD8+ T-lymphocyte cell ratios were measured in four dehydrated men (ages 30-46 yr) before and after 70 min of supine submaximal (71 % VO(sub 2max) lower extremity cycle exercise. Just before exercise, Evans blue dye was injected for measurement of plasma volume. The subjects then drank one of six fluid formulations (12 ml/kg) in 3-4 min. All six mean post-hydration (pre-exercise) CD4+/CD8+ ratios (Becton-Dickinson Fluorescence Activated Cell Sorter and FACScan Consort-30 software program were below the normal range of 1.2-1.5; mean (+/- SE) and range were 0.77 +/- 0.12 and 0.39-1.15, respectively. The post-exercise ratios increased: mean = 1.36 =/- 0.15 (P less than 0.05) and range = 0.98-1.98. Regression of mean CD4+/CD8+ ratios on mean plasma osmolality resulted in pre- and post-exercise correlation coefficients of -0.76 (P less than 0.10) and -0.92 (P less than 0.01), respectively. The decreased pre-exercise ratios (after drinking) were probably not caused by the Evans blue dye but appeared to be associated more with the stress (osmotic) of dehydration. The increased post-exercise ratios to normal levels accompanied the rehydration and were not due to the varied electrolyte and osmotic concentrations of the ingested fluids or to the varied vascular volume shifts during exercise. Thus, the level of subject hydration and plasma osmotality may be factors involved in the mechanism of immune system modulation induced by exercise.

Wearable Wide-Range Strain Sensors Based on Ionic Liquids and Monitoring of Human Activities

PubMed Central

Zhang, Shao-Hui; Wang, Feng-Xia; Li, Jia-Jia; Peng, Hong-Dan; Yan, Jing-Hui; Pan, Ge-Bo

2017-01-01

Wearable sensors for detection of human activities have encouraged the development of highly elastic sensors. In particular, to capture subtle and large-scale body motion, stretchable and wide-range strain sensors are highly desired, but still a challenge. Herein, a highly stretchable and transparent stain sensor based on ionic liquids and elastic polymer has been developed. The as-obtained sensor exhibits impressive stretchability with wide-range strain (from 0.1% to 400%), good bending properties and high sensitivity, whose gauge factor can reach 7.9. Importantly, the sensors show excellent biological compatibility and succeed in monitoring the diverse human activities ranging from the complex large-scale multidimensional motions to subtle signals, including wrist, finger and elbow joint bending, finger touch, breath, speech, swallow behavior and pulse wave. PMID:29135928

Activity budget and ranging patterns of Colobus vellerosus in forest fragments in central Ghana.

PubMed

Wong, Sarah N P; Sicotte, Pascale

2007-01-01

The forest fragments surrounding the 192-ha Boabeng-Fiema Monkey Sanctuary (BFMS) in central Ghana contain small populations of Colobus vellerosus. Data were collected on activity budget, ranging patterns and habitat use of 3 groups living in these small fragments in August-November 2003, and compared to 3 BFMS groups. Fragment groups spent less time moving and more time resting than BFMS groups. Home ranges of fragment groups tended to be smaller than those of BFMS groups. Fragment and BFMS groups used similarly sized trees. Comparisons of activity budget and ranging between fragments and the BFMS suggest that fragment habitat quality was sufficient to sustain current numbers. These behavioral trends are consistent with a concurrent study that we conducted investigating ecological quality in the same fragments. Copyright 2007 S. Karger AG, Basel.

Element Abundance Ratios in the Quiet Sun Transition Region

NASA Astrophysics Data System (ADS)

Young, P. R.

2018-03-01

Element abundance ratios of magnesium to neon (Mg/Ne) and neon to oxygen (Ne/O) in the transition region of the quiet Sun have been derived by re-assessing previously published data from the Coronal Diagnostic Spectrometer on board the Solar and Heliospheric Observatory in the light of new atomic data. The quiet Sun Mg/Ne ratio is important for assessing the effect of magnetic activity on the mechanism of the first ionization potential (FIP) effect, while the Ne/O ratio can be used to infer the solar photospheric abundance of neon, which cannot be measured directly. The average Mg/Ne ratio is found to be 0.52 ± 0.11, which applies over the temperature region 0.2–0.7 MK, and is consistent with the earlier study. The Ne/O ratio is, however, about 40% larger, taking the value 0.24 ± 0.05 that applies to the temperature range 0.08–0.40 MK. The increase is mostly due to changes in ionization and recombination rates that affect the equilibrium ionization balance. If the Ne/O ratio is interpreted as reflecting the photospheric ratio, then the photospheric neon abundance is 8.08 ± 0.09 or 8.15 ± 0.10 (on a logarithmic scale for which hydrogen is 12), according to whether the oxygen abundances of M. Asplund et al. or E. Caffau et al. are used. The updated photospheric neon abundance implies a Mg/Ne FIP bias for the quiet Sun of 1.6 ± 0.6.

UV activation of polymeric high aspect ratio microstructures: ramifications in antibody surface loading for circulating tumor cell selection.

PubMed

Jackson, Joshua M; Witek, Małgorzata A; Hupert, Mateusz L; Brady, Charles; Pullagurla, Swathi; Kamande, Joyce; Aufforth, Rachel D; Tignanelli, Christopher J; Torphy, Robert J; Yeh, Jen Jen; Soper, Steven A

2014-01-07

The need to activate thermoplastic surfaces using robust and efficient methods has been driven by the fact that replication techniques can be used to produce microfluidic devices in a high production mode and at low cost, making polymer microfluidics invaluable for in vitro diagnostics, such as circulating tumor cell (CTC) analysis, where device disposability is critical to mitigate artifacts associated with sample carryover. Modifying the surface chemistry of thermoplastic devices through activation techniques can be used to increase the wettability of the surface or to produce functional scaffolds to allow for the covalent attachment of biologics, such as antibodies for CTC recognition. Extensive surface characterization tools were used to investigate UV activation of various surfaces to produce uniform and high surface coverage of functional groups, such as carboxylic acids in microchannels of different aspect ratios. We found that the efficiency of the UV activation process is highly dependent on the microchannel aspect ratio and the identity of the thermoplastic substrate. Colorimetric assays and fluorescence imaging of UV-activated microchannels following EDC/NHS coupling of Cy3-labeled oligonucleotides indicated that UV-activation of a PMMA microchannel with an aspect ratio of ~3 was significantly less efficient toward the bottom of the channel compared to the upper sections. This effect was a consequence of the bulk polymer's damping of the modifying UV radiation due to absorption artifacts. In contrast, this effect was less pronounced for COC. Moreover, we observed that after thermal fusion bonding of the device's cover plate to the substrate, many of the generated functional groups buried into the bulk rendering them inaccessible. The propensity of this surface reorganization was found to be higher for PMMA compared to COC. As an example of the effects of material and microchannel aspect ratios on device functionality, thermoplastic devices for the

Relative phase asynchrony and long-range correlation of long-term solar magnetic activity

NASA Astrophysics Data System (ADS)

Deng, Linhua

2017-07-01

Statistical signal processing is one of the most important tasks in a large amount of areas of scientific studies, such as astrophysics, geophysics, and space physics. Phase recurrence analysis and long-range persistence are the two dynamical structures of the underlying processes for the given natural phenomenon. Linear and nonlinear time series analysis approaches (cross-correlation analysis, cross-recurrence plot, wavelet coherent transform, and Hurst analysis) are combined to investigate the relative phase interconnection and long-range correlation between solar activity and geomagnetic activity for the time interval from 1932 January to 2017 January. The following prominent results are found: (1) geomagnetic activity lags behind sunspot numbers with a phase shift of 21 months, and they have a high level of asynchronous behavior; (2) their relative phase interconnections are in phase for the periodic scales during 8-16 years, but have a mixing behavior for the periodic belts below 8 years; (3) both sunspot numbers and geomagnetic activity can not be regarded as a stochastic phenomenon because their dynamical behaviors display a long-term correlation and a fractal nature. We believe that the presented conclusions could provide further information on understanding the dynamical coupling of solar dynamo process with geomagnetic activity variation, and the crucial role of solar and geomagnetic activity in the long-term climate change.

Mean individual muscle activities and ratios of total muscle activities in a selective muscle strengthening experiment: the effects of lower limb muscle activity based on mediolateral slope angles during a one-leg stance.

PubMed

Lee, Sang-Yeol

2016-09-01

[Purpose] The purpose of this study was to provide basic data for research on selective muscle strengthening by identifying mean muscle activities and calculating muscle ratios for use in developing strengthening methods. [Subjects and Methods] Twenty-one healthy volunteers were included in this study. Muscle activity was measured during a one-leg stance under 6 conditions of slope angle: 0°, 5°, 10°, 15°, 20°, and 25°. The data used in the analysis were root mean square and % total muscle activity values. [Results] There were significant differences in the root mean square of the gluteus medius, the hamstring, and the medial gastrocnemius muscles. There were significant differences in % total muscle activity of the medial gastrocnemius. [Conclusion] Future studies aimed at developing selective muscle strengthening methods are likely to yield more effective results by using muscle activity ratios based on electromyography data.

Glacial reorganization of topography in a tectonically active mountain range

NASA Astrophysics Data System (ADS)

Adams, Byron; Ehlers, Todd

2016-04-01

Tests of the interactions between tectonic and climate forcing on Earth's topography often focus on the concept of steady-state whereby processes of rock deformation and erosion are opposing and equal. However, when conditions change such as the climate or tectonic rock uplift, then surface processes act to restore the balance between rock deformation and erosion by adjusting topography. Most examples of canonical steady-state mountain ranges lie within the northern hemisphere, which underwent a radical change in the Quaternary due to the onset of widespread glaciation. The activity of glaciers changed erosion rates and topography in many of these mountain ranges, which likely violates steady-state assumptions. With new topographic analysis, and existing patterns of climate and rock uplift, we explore a mountain range previously considered to be in steady-state, the Olympic Mountains, USA. The details of our analysis suggest the dominant topographic signal in the Olympic Mountains is a spatial, and likely temporal, variation in erosional efficiency dictated by orographic precipitation, and Pleistocene glacier ELA patterns, and not tectonic rock uplift rates. Alpine glaciers drastically altered the relief structure of the Olympic Mountains. The details of these relief changes are recorded in channel profiles as overdeepenings, reduced slopes, and associated knickpoints. We find the position of these relief changes within the orogen is dependent on the position of the Pleistocene ELA. While alpine glaciers overdeepened valleys in regions near the Pleistocene ELA (which has a tendency to increase relief), headward erosion of west and north flowing glacier systems captured significant area from opposing systems and caused drainage divide lowering. This divide lowering reduced relief throughout the range. We demonstrate similar topographic effects recorded in the basin hypsometries of other Cenozoic mountain ranges around the world. The significant glacial overprint on

Temporal variability of local abundance, sex ratio and activity in the Sardinian chalk hill blue butterfly

USGS Publications Warehouse

Casula, P.; Nichols, J.D.

2003-01-01

When capturing and marking of individuals is possible, the application of newly developed capture-recapture models can remove several sources of bias in the estimation of population parameters such as local abundance and sex ratio. For example, observation of distorted sex ratios in counts or captures can reflect either different abundances of the sexes or different sex-specific capture probabilities, and capture-recapture models can help distinguish between these two possibilities. Robust design models and a model selection procedure based on information-theoretic methods were applied to study the local population structure of the endemic Sardinian chalk hill blue butterfly, Polyommatus coridon gennargenti. Seasonal variations of abundance, plus daily and weather-related variations of active populations of males and females were investigated. Evidence was found of protandry and male pioneering of the breeding space. Temporary emigration probability, which describes the proportion of the population not exposed to capture (e.g. absent from the study area) during the sampling process, was estimated, differed between sexes, and was related to temperature, a factor known to influence animal activity. The correlation between temporary emigration and average daily temperature suggested interpreting temporary emigration as inactivity of animals. Robust design models were used successfully to provide a detailed description of the population structure and activity in this butterfly and are recommended for studies of local abundance and animal activity in the field.

Generic Long-Range Interactions Between Passive Bodies in an Active Fluid.

PubMed

Baek, Yongjoo; Solon, Alexandre P; Xu, Xinpeng; Nikola, Nikolai; Kafri, Yariv

2018-02-02

A single nonspherical body placed in an active fluid generates currents via breaking of time-reversal symmetry. We show that, when two or more passive bodies are placed in an active fluid, these currents lead to long-range interactions. Using a multipole expansion, we characterize their leading-order behaviors in terms of single-body properties and show that they decay as a power law with the distance between the bodies, are anisotropic, and do not obey an action-reaction principle. The interactions lead to rich dynamics of the bodies, illustrated by the spontaneous synchronized rotation of pinned nonchiral bodies and the formation of traveling bound pairs. The occurrence of these phenomena depends on tunable properties of the bodies, thus opening new possibilities for self-assembly mediated by active fluids.

Nearly constant ratio between the proton inertial scale and the spectrum break length scale in the plasma beta range from 0.2 to 1.4 in the solar wind turbulence

NASA Astrophysics Data System (ADS)

Wang, X.; Tu, C. Y.; He, J.; Wang, L.

2017-12-01

The spectrum break at the ion scale of the solar wind magnetic fluctuations are considered to give important clue on the turbulence dissipation mechanism. Among several possible mechanisms, the most notable ones are the two mechanisms that related respectively with proton thermal gyro-radius and proton inertial length. However, no definite conclusion has been given for which one is more reasonable because the two parameters have similar values in the normal plasma beta range. Here we do a statistical study for the first time to see if the two mechanism predictions have different dependence on the solar wind velocity and on the plasma beta in the normal plasma beta range in the solar wind at 1 AU. From magnetic measurements by Wind, Ulysses and Messenger, we select 60 data sets with duration longer than 8 hours. We found that the ratio between the proton inertial scale and the spectrum break scale do not change considerably with both varying the solar wind speed from 300km/s to 800km/s and varying the plasma beta from 0.2 to 1.4. The average value of the ratio times 2pi is 0.46 ± 0.08. However, the ratio between the proton gyro-radius and the break scale changes clearly. This new result shows that the proton inertial scale could be a single factor that determines the break length scale and hence gives a strong evidence to support the dissipation mechanism related to it in the normal plasma beta range. The value of the constant ratio may relate with the dissipation mechanism, but it needs further theoretical study to give detailed explanation.

Assessment of Anaerobic Toluene Biodegradation Activity by bssA Transcript/Gene Ratios

PubMed Central

Brow, Christina N.; O'Brien Johnson, Reid; Johnson, Richard L.

2013-01-01

Benzylsuccinate synthase (bssA) genes associated with toluene degradation were profiled across a groundwater contaminant plume under nitrate-reducing conditions and were detected in significant numbers throughout the plume. However, differences between groundwater and core sediment samples suggested that microbial transport, rather than local activity, was the underlying cause of the high copy numbers within the downgradient plume. Both gene transcript and reactant concentrations were consistent with this hypothesis. Expression of bssA genes from denitrifying toluene degraders was induced by toluene but only in the presence of nitrate, and transcript abundance dropped rapidly following the removal of either toluene or nitrate. The drop in bssA transcripts following the removal of toluene could be described by an exponential decay function with a half-life on the order of 1 h. Interestingly, bssA transcripts never disappeared completely but were always detected at some level if either inducer was present. Therefore, the detection of transcripts alone may not be sufficient evidence for contaminant degradation. To avoid mistakenly associating basal-level gene expression with actively degrading microbial populations, an integrated approach using the ratio of functional gene transcripts to gene copies is recommended. This approach minimizes the impact of microbial transport on activity assessment and allows reliable assessments of microbial activity to be obtained from water samples. PMID:23811506

Does proprioceptive acuity during active knee rotation in the transverse plane vary at different ranges?

PubMed

Muaidi, Qassim I

2016-11-21

Knee proprioception in the sagittal plane has been widely investigated in prospective studies, however limited information is known about proprioceptive acuity during active knee rotation and the way most commonly injured. To investigate whether proprioceptive acuity during active internal and external knee rotation varies at different ranges in the transverse plane. Healthy volunteers (N: 26) without previous injury or surgery of the knee joint participated in the study.Knee rotation proprioceptive acuity was measured using a custom-designed device. The measure of proprioceptive acuity used in this study was the just-noticeable-difference (JND). Participants actively rotated the knee at different intervals(initial, mid, and terminal internal or external rotation range) to one of four movement blocks and the magnitude of the permitted motion was judged. The means of the JND for proprioceptive acuity at initial internal rotation (0.80° ± 0.06) were significantly (p< 0.002) lower than for mid (1.62° ± 0.18), and terminal (2.08° ± 0.35) internal rotation. The means of the JND for proprioceptive acuity at initial external rotation (1.16° ± 0.10) were significantly (p< 0.04) lower than for mid (1.95° ± 0.30), and terminal (1.97° ± 0.24) internal rotation. Participants perceived smaller differences between active internal and external rotation movements at initial rotation range than at the mid and terminal rotation range of movement. This suggests better proprioceptive acuity at the initial rotation range of movement in the transverse plane.

Marine and freshwater concentration ratios (CR(wo-water)): review of Japanese data.

PubMed

Tagami, K; Uchida, S

2013-12-01

The water-to-organism (whole body) concentration ratio (CR(wo-water)), which is defined as the ratio of the concentration of a radionuclide in the biota (Bq kg(-1) fresh weight) to that in water (Bq L(-1)), has been used in mathematical models for environmental radiation protection. In the present paper, published global fallout (90)Sr, (137)Cs, (106)Ru, (144)Ce and (239+240)Pu activity concentration data and stable element concentration data for Na, K, Ca, Mg, Fe, Cu and Mn for organisms living in freshwater or seawater areas in Japan were collated. The data suitable for obtaining CR(wo-water) values were identified. CR(wo-water) values of (137)Cs were similar for pelagic fish, benthic fish and whitebait (immature, small fish) with respective geometric means of 30 (range: 4.4-69), 32 (range: 15-54) and 33 (range: 13-84). The calculated CR(wo-water) values of the other radionuclides and stable elements were generally similar to other previously reported values; with the exception that those for Ce were lower for marine biota and those of Cu were higher for freshwater fish. Copyright © 2012 Elsevier Ltd. All rights reserved.

An investigation of several NACA 1 series axisymmetric inlets at Mach numbers from 0.4 to 1.29. [wind tunnel tests over range of mass-flow ratios and at angle of attack

NASA Technical Reports Server (NTRS)

Re, R. J.

1974-01-01

An investigation was conducted in the Langley 16-foot transonic tunnel to determine the performance of seven inlets having NACA 1-series contours and one inlet having an elliptical contour over a range of mass-flow ratios and at angle of attack. The inlet diameter ratio varied from 0.81 to 0.89; inlet length ratio varied from 0.75 to 1.25; and internal contraction ratio varied from 1.009 to 1.093. Reynolds number based on inlet maximum diameter varied from 3.4 million at a Mach number of 0.4 to 5.6 million at a Mach number of 1.29.

Environmental impacts of training activities at an air weapons range.

PubMed

Bordeleau, Geneviève; Martel, Richard; Ampleman, Guy; Thiboutot, Sonia

2008-01-01

Within Canada, it has been recognized in the last decade that military training activities may have impacts on the environmental quality of training ranges. However, impacts of activities specific to Air Force Bases have not yet been intensely documented. A hydrogeological study was accomplished at the Cold Lake Air Weapons Range, Alberta, to evaluate the environmental impacts of using bombs, rockets, strafing, and open burning/open detonation (OB/OD) on the quality of soil, ground water, surface water, and lake sediments. Samples were analyzed for metals, anions, ammonium perchlorate (NH(4)ClO(4)), and energetic materials (EM). It was found that training activities did not result in measured values being exceeded on the basis of guidance values for surface water and lake sediments. Contamination by metals was mostly limited to soils, and some metals may be related to the use of bombs (Cd, Cu, Pb), strafe (Cu), and rockets (As, Ba, Cd, Cr, Cu, Fe, Ni, Pb, U, V, Zn). TNT (2,4,6-trinitrotoluene) was the main EM found in soils, while RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was more common in ground water. Both are related to live bombing, while nitroglycerine (NG) is related to rocket use and was detected in soils only. Aluminum, nitrate, and ammonium perchlorate detected in ground water may be related to live bombing or rockets. OB/OD operations resulted in the presence of various EM in soils, and of perchlorate and nitrate in ground water. Contamination by metals and explosives in soils was localized around the targets and varied significantly in time; however, in ground water it was more constant and may persist for a period of several years after a target has been removed.

A SYSTEMATIC REVIEW OF THE EXERCISES THAT PRODUCE OPTIMAL MUSCLE RATIOS OF THE SCAPULAR STABILIZERS IN NORMAL SHOULDERS

PubMed Central

Schory, Abbey; Bidinger, Erik; Wolf, Joshua

2016-01-01

ABSTRACT Purpose The purpose of this systematic review was to determine the exercises that optimize muscle ratios of the periscapular musculature for scapular stability and isolated strengthening. Methods A systematic search was performed in PubMed, CINAHL, SPORTDiscus, Scopus, and Discovery Layer. Studies were included if they examined the muscle activation of the upper trapezius compared to the middle trapezius, lower trapezius, or serratus anterior using EMG during open chain exercises. The participants were required to have healthy, nonpathological shoulders. Information obtained included maximal voluntary isometric contraction (MVIC) values, ratios, standard deviations, exercises, and exercise descriptions. The outcome of interest was determining exercises that create optimal muscle activation ratios between the scapular stabilizers. Results Fifteen observational studies met the inclusion criteria for the systematic review. Exercises with optimal ratios were eccentric exercises in the frontal and sagittal planes, especially flexion between 180 ° and 60 °. External rotation exercises with the elbow flexed to 90 ° also had optimal ratios for activating the middle trapezius in prone and side-lying positions. Exercises with optimal ratios for the lower trapezius were prone flexion, high scapular retraction, and prone external rotation with the shoulder abducted to 90 ° and elbow flexed. Exercises with optimal ratios for the serratus anterior were the diagonal exercises and scapular protraction. Conclusion This review has identified optimal positions and exercises for periscapular stability exercises. Standing exercises tend to activate the upper trapezius at a higher ratio, especially during the 60-120 ° range. The upper trapezius was the least active, while performing exercises in prone, side-lying, and supine positions. More studies need to be conducted to examine these exercises in greater detail and confirm their consistency in producing the

A tabulation of pipe length to diameter ratios as a function of Mach number and pressure ratios for compressible flow

NASA Technical Reports Server (NTRS)

Dixon, G. V.; Barringer, S. R.; Gray, C. E.; Leatherman, A. D.

1975-01-01

Computer programs and resulting tabulations are presented of pipeline length-to-diameter ratios as a function of Mach number and pressure ratios for compressible flow. The tabulations are applicable to air, nitrogen, oxygen, and hydrogen for compressible isothermal flow with friction and compressible adiabatic flow with friction. Also included are equations for the determination of weight flow. The tabulations presented cover a wider range of Mach numbers for choked, adiabatic flow than available from commonly used engineering literature. Additional information presented, but which is not available from this literature, is unchoked, adiabatic flow over a wide range of Mach numbers, and choked and unchoked, isothermal flow for a wide range of Mach numbers.

Plutonium activities and 240Pu/ 239Pu atom ratios in sediment cores from the east China sea and Okinawa Trough: Sources and inventories

NASA Astrophysics Data System (ADS)

Wang, Zhong-liang; Yamada, Masatoshi

2005-05-01

Plutonium concentrations and 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediment cores were determined by isotope dilution inductively coupled plasma mass spectrometry after separation using ion-exchange chromatography. The results showed that 240Pu/ 239Pu atom ratios in the East China Sea and Okinawa Trough sediments, ranging from 0.21 to 0.33, were much higher than the reported value of global fallout (0.18). The highest 240Pu/ 239Pu ratios (0.32-0.33) were observed in the deepest Okinawa Trough sediment samples. These ratios suggested the US nuclear weapons tests in the early 1950s at the Pacific Proving Grounds in the Marshall Islands were a major source of plutonium in the East China Sea and Okinawa Trough sediments, in addition to the global fallout source. It was proposed that close-in fallout plutonium was delivered from the Pacific Proving Grounds test sites via early direct tropospheric fallout and transportation by the North Pacific Equatorial Circulation system and Kuroshio Current into the Okinawa Trough and East China Sea. The total 239 + 240 Pu inventories in the cores were about 150-200% of that expected from direct global fallout; about 46-67% of the total inventories were delivered from the Pacific Proving Grounds. Much higher 239 + 240 Pu inventories were observed in the East China Sea sediments than in sediments of the Okinawa Trough, because in the open oceans, part of the 239 + 240 Pu was still retained in the water column, and continued Pu scavenging was higher over the margin than the trough. According to the vertical distributions of 239 + 240 Pu activities and 240Pu/ 239Pu atom ratios in these cores, it was concluded that sediment mixing was the dominant process in controlling profiles of plutonium in this area. Faster mixing in the coastal samples has homogenized the entire 240Pu/ 239Pu ratio record today; slightly slower mixing and less scavenging in the Okinawa Trough have left the surface sediment ratios closer

Dean Flow Dynamics in Low-Aspect Ratio Spiral Microchannels

PubMed Central

Nivedita, Nivedita; Ligrani, Phillip; Papautsky, Ian

2017-01-01

A wide range of microfluidic cell-sorting devices has emerged in recent years, based on both passive and active methods of separation. Curvilinear channel geometries are often used in these systems due to presence of secondary flows, which can provide high throughput and sorting efficiency. Most of these devices are designed on the assumption of two counter rotating Dean vortices present in the curved rectangular channels and existing in the state of steady rotation and amplitude. In this work, we investigate these secondary flows in low aspect ratio spiral rectangular microchannels and define their development with respect to the channel aspect ratio and Dean number. This work is the first to experimentally and numerically investigate Dean flows in microchannels for Re > 100, and show presence of secondary Dean vortices beyond a critical Dean number. We further demonstrate the impact of these multiple vortices on particle and cell focusing. Ultimately, this work offers new insights into secondary flow instabilities for low-aspect ratio, spiral microchannels, with improved flow models for design of more precise and efficient microfluidic devices for applications such as cell sorting and micromixing. PMID:28281579

Microprocessor realizations of range rate filters

NASA Technical Reports Server (NTRS)

1979-01-01

The performance of five digital range rate filters is evaluated. A range rate filter receives an input of range data from a radar unit and produces an output of smoothed range data and its estimated derivative range rate. The filters are compared through simulation on an IBM 370. Two of the filter designs are implemented on a 6800 microprocessor-based system. Comparisons are made on the bases of noise variance reduction ratios and convergence times of the filters in response to simulated range signals.

Arcjet nozzle area ratio effects

NASA Technical Reports Server (NTRS)

Curran, Francis M.; Sarmiento, Charles J.; Birkner, Bjorn W.; Kwasny, James

1990-01-01

An experimental investigation was conducted to determine the effect of nozzle area ratio on the operating characteristics and performance of a low power dc arcjet thruster. Conical thoriated tungsten nozzle inserts were tested in a modular laboratory arcjet thruster run on hydrogen/nitrogen mixtures simulating the decomposition products of hydrazine. The converging and diverging sides of the inserts had half angles of 30 and 20 degrees, respectively, similar to a flight type unit currently under development. The length of the diverging side was varied to change the area ratio. The nozzle inserts were run over a wide range of specific power. Current, voltage, mass flow rate, and thrust were monitored to provide accurate comparisons between tests. While small differences in performance were observed between the two nozzle inserts, it was determined that for each nozzle insert, arcjet performance improved with increasing nozzle area ratio to the highest area ratio tested and that the losses become very pronounced for area ratios below 50. These trends are somewhat different than those obtained in previous experimental and analytical studies of low Re number nozzles. It appears that arcjet performance can be enhanced via area ratio optimization.

Arcjet Nozzle Area Ratio Effects

NASA Technical Reports Server (NTRS)

Curran, Francis M.; Sarmiento, Charles J.; Birkner, Bjorn W.; Kwasny, James

1990-01-01

An experimental investigation was conducted to determine the effect of nozzle area ratio on the operating characteristics and performance of a low power dc arcjet thruster. Conical thoriated tungsten nozzle inserts were tested in a modular laboratory arcjet thruster run on hydrogen/nitrogen mixtures simulating the decomposition products of hydrazine. The converging and diverging sides of the inserts had half angles of 30 and 20 degrees, respectively, similar to a flight type unit currently under development. The length of the diverging side was varied to change the area ratio. The nozzle inserts were run over a wide range of specific power. Current, voltage, mass flow rate, and thrust were monitored to provide accurate comparisons between tests. While small differences in performance were observed between the two nozzle inserts, it was determined that for each nozzle insert, arcjet performance improved with increasing nozzle area ratio to the highest area ratio tested and that the losses become very pronounced for area ratios below 50. These trends are somewhat different than those obtained in previous experimental and analytical studies of low Re number nozzles. It appears that arcjet performance can be enhanced via area ratio optimization.

Administrator/Student Ratios in Large School Districts.

ERIC Educational Resources Information Center

Ornstein, Allan C.

1989-01-01

According to a survey of large school districts, the ratio of central office managers to students enrolled ranges from 1 administrator per 1,650 students to 1 administrator per 161 students. The average ratio was 1 administrator per 561 students. Western school districts appear most efficient. The ideal: 1 administrator per 1,000 to 1,200…

Surface compositional mapping by spectral ratioing of ERTS-1 MSS data in the Wind River Basin and Range, Wyoming

NASA Technical Reports Server (NTRS)

Vincent, R. K. (Principal Investigator); Salmon, B. C.; Pillars, W. W.; Harris, J. E.

1975-01-01

The author has identified the following significant results. ERTS data collected in August and October 1972 were processed on digital and special purpose analog recognition computers using ratio enhancement and pattern recognition. Ratios of band-averaged laboratory reflectances of some minerals and rock types known to be in the scene compared favorably with ratios derived from the data by ratio normalization procedures. A single ratio display and density slice of the visible channels of ERTS MSS data, Channel 5/Channel 4 (R5,4), separated the Triassic Chugwater formation (redbeds) from other formations present and may have enhanced iron oxide minerals present at the surface in abundance. Comparison of data sets collected over the same area at two different times of the year by digital processing indicated that spectral variation due to environmental factors was reduced by ratio processing.

Comparison of the Hamstring Muscle Activity and Flexion-Relaxation Ratio between Asymptomatic Persons and Computer Work-related Low Back Pain Sufferers.

PubMed

Kim, Min-Hee; Yoo, Won-Gyu

2013-05-01

[Purpose] The purpose of this study was to compare the hamstring muscle (HAM) activities and flexion-relaxation ratios of an asymptomatic group and a computer work-related low back pain (LBP) group. [Subjects] For this study, we recruited 10 asymptomatic computer workers and 10 computer workers with work-related LBP. [Methods] We measured the RMS activity of each phase (flexion, full-flexion, and re-extension phase) of trunk flexion and calculated the flexion-relaxation (FR) ratio of the muscle activities of the flexion and full-flexion phases. [Results] In the computer work-related LBP group, the HAM muscle activity increased during the full-flexion phase compared to the asymptomatic group, and the FR ration was also significantly higher. [Conclusion] We thought that prolonged sitting of computer workers might cause the change in their HAM muscle activity pattern.

On the Use of Line Depth Ratios to Measure Starspot Properties on Magnetically Active Stars

NASA Astrophysics Data System (ADS)

O'Neal, Douglas

2006-07-01

Photometric and spectroscopic techniques have proven to be effective ways to measure the properties of dark, cool starspots on magnetically active stars. Recently, a technique was introduced using atomic line depth ratios (LDRs) to measure starspot properties. Carefully reproducing this technique using a new set of spectroscopic observations of active stars, we find that the LDR technique encounters difficulties, specifically by overestimating spot temperatures (because the atomic lines blend with titanium oxide absorption in cooler spots) and by not tightly constraining the filling factor of spots. While the use of LDRs for active star studies has great promise, we believe that these concerns need to be addressed before the technique is more widely applied. This paper includes data taken at McDonald Observatory of the University of Texas at Austin.

Effect of coolant flow ejection on aerodynamic performance of low-aspect-ratio vanes. 2: Performance with coolant flow ejection at temperature ratios up to 2

NASA Technical Reports Server (NTRS)

Hass, J. E.; Kofskey, M. G.

1977-01-01

The aerodynamic performance of a 0.5 aspect ratio turbine vane configuration with coolant flow ejection was experimentally determined in a full annular cascade. The vanes were tested at a nominal mean section ideal critical velocity ratio of 0.890 over a range of primary to coolant total temperature ratio from 1.0 to 2.08 and a range of coolant to primary total pressure ratio from 1.0 to 1.4 which corresponded to coolant flows from 3.0 to 10.7 percent of the primary flow. The variations in primary and thermodynamic efficiency and exit flow conditions with circumferential and radial position were obtained.

Changes in active ankle dorsiflexion range of motion after acute inversion ankle sprain.

PubMed

Youdas, James W; McLean, Timothy J; Krause, David A; Hollman, John H

2009-08-01

Posterior calf stretching is believed to improve active ankle dorsiflexion range of motion (AADFROM) after acute ankle-inversion sprain. To describe AADFROM at baseline (postinjury) and at 2-wk time periods for 6 wk after acute inversion sprain. Randomized trial. Sports clinic. 11 men and 11 women (age range 11-54 y) with acute inversion sprain. Standardized home exercise program for acute inversion sprain. AADFROM with the knee extended. Time main effect on AADFROM was significant (F3,57 = 108, P < .001). At baseline, mean active sagittal-plane motion of the ankle was 6 degrees of plantar flexion, whereas at 2, 4, and 6 wk AADFROM was 7 degrees, 11 degrees, and 11 degrees, respectively. AADFROM increased significantly from baseline to week 2 and from week 2 to week 4. Normal AADFROM was restored within 4 wk after acute inversion sprain.

Dyslipidemia and Diabetes Increase the OPG/TRAIL Ratio in the Cardiovascular System.

PubMed

Toffoli, Barbara; Fabris, Bruno; Bartelloni, Giacomo; Bossi, Fleur; Bernardi, Stella

2016-01-01

Background . Dyslipidemia and diabetes are two of the most well established risk factors for the development of cardiovascular disease (CVD). Both of them usually activate a complex range of pathogenic pathways leading to organ damage. Here we hypothesized that dyslipidemia and diabetes could affect osteoprotegerin (OPG) and TNF-related apoptosis-inducing ligand (TRAIL) expression in the vessels and the heart. Materials and Methods . Gene and protein expression of OPG, TRAIL, and OPG/TRAIL ratio were quantified in the aorta and the hearts of control mice, dyslipidemic mice, and diabetic mice. Results . Diabetes significantly increased OPG and the OPG/TRAIL ratio expression in the aorta, while dyslipidemia was the major determinant of the changes observed in the heart, where it significantly increased OPG and reduced TRAIL expression, thus increasing cardiac OPG/TRAIL ratio. Conclusions . This work shows that both dyslipidemia and diabetes affect OPG/TRAIL ratio in the cardiovascular system. This could contribute to the changes in circulating OPG/TRAIL which are observed in patients with diabetes and CVD. Most importantly, these changes could mediate/contribute to atherosclerosis development and cardiac remodeling.

Influence of spectral resolution, spectral range and signal-to-noise ratio of Fourier transform infra-red spectra on identification of high explosive substances

NASA Astrophysics Data System (ADS)

Banas, Krzysztof; Banas, Agnieszka M.; Heussler, Sascha P.; Breese, Mark B. H.

2018-01-01

In the contemporary spectroscopy there is a trend to record spectra with the highest possible spectral resolution. This is clearly justified if the spectral features in the spectrum are very narrow (for example infra-red spectra of gas samples). However there is a plethora of samples (in the liquid and especially in the solid form) where there is a natural spectral peak broadening due to collisions and proximity predominately. Additionally there is a number of portable devices (spectrometers) with inherently restricted spectral resolution, spectral range or both, which are extremely useful in some field applications (archaeology, agriculture, food industry, cultural heritage, forensic science). In this paper the investigation of the influence of spectral resolution, spectral range and signal-to-noise ratio on the identification of high explosive substances by applying multivariate statistical methods on the Fourier transform infra-red spectral data sets is studied. All mathematical procedures on spectral data for dimension reduction, clustering and validation were implemented within R open source environment.

Soft network materials with isotropic negative Poisson's ratios over large strains.

PubMed

Liu, Jianxing; Zhang, Yihui

2018-01-31

Auxetic materials with negative Poisson's ratios have important applications across a broad range of engineering areas, such as biomedical devices, aerospace engineering and automotive engineering. A variety of design strategies have been developed to achieve artificial auxetic materials with controllable responses in the Poisson's ratio. The development of designs that can offer isotropic negative Poisson's ratios over large strains can open up new opportunities in emerging biomedical applications, which, however, remains a challenge. Here, we introduce deterministic routes to soft architected materials that can be tailored precisely to yield the values of Poisson's ratio in the range from -1 to 1, in an isotropic manner, with a tunable strain range from 0% to ∼90%. The designs rely on a network construction in a periodic lattice topology, which incorporates zigzag microstructures as building blocks to connect lattice nodes. Combined experimental and theoretical studies on broad classes of network topologies illustrate the wide-ranging utility of these concepts. Quantitative mechanics modeling under both infinitesimal and finite deformations allows the development of a rigorous design algorithm that determines the necessary network geometries to yield target Poisson ratios over desired strain ranges. Demonstrative examples in artificial skin with both the negative Poisson's ratio and the nonlinear stress-strain curve precisely matching those of the cat's skin and in unusual cylindrical structures with engineered Poisson effect and shape memory effect suggest potential applications of these network materials.

Effect of reinforcer magnitude on performance maintained by progressive-ratio schedules.

PubMed

Rickard, J F; Body, S; Zhang, Z; Bradshaw, C M; Szabadi, E

2009-01-01

This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive-ratio schedules. Fifteen rats were trained under a progressive-ratio schedule in seven phases of the experiment in which the volume of a 0.6-M sucrose solution reinforcer was varied within the range 6-300 microl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The "specific activation" parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the "response time" parameter, delta, which defines the minimum response time, increased as a function of reinforcer volume; the "currency" parameter, beta, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive-ratio schedules in behavioral neuroscience are discussed.

Dose ratio proton radiography using the proximal side of the Bragg peak

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doolan, P. J., E-mail: paul.doolan.09@ucl.ac.uk; Royle, G.; Gibson, A.

Purpose: In recent years, there has been a movement toward single-detector proton radiography, due to its potential ease of implementation within the clinical environment. One such single-detector technique is the dose ratio method in which the dose maps from two pristine Bragg peaks are recorded beyond the patient. To date, this has only been investigated on the distal side of the lower energy Bragg peak, due to the sharp falloff. The authors investigate the limits and applicability of the dose ratio method on the proximal side of the lower energy Bragg peak, which has the potential to allow a muchmore » wider range of water-equivalent thicknesses (WET) to be imaged. Comparisons are made with the use of the distal side of the Bragg peak. Methods: Using the analytical approximation for the Bragg peak, the authors generated theoretical dose ratio curves for a range of energy pairs, and then determined how an uncertainty in the dose ratio would translate to a spread in the WET estimate. By defining this spread as the accuracy one could achieve in the WET estimate, the authors were able to generate lookup graphs of the range on the proximal side of the Bragg peak that one could reliably use. These were dependent on the energy pair, noise level in the dose ratio image and the required accuracy in the WET. Using these lookup graphs, the authors investigated the applicability of the technique for a range of patient treatment sites. The authors validated the theoretical approach with experimental measurements using a complementary metal oxide semiconductor active pixel sensor (CMOS APS), by imaging a small sapphire sphere in a high energy proton beam. Results: Provided the noise level in the dose ratio image was 1% or less, a larger spread of WETs could be imaged using the proximal side of the Bragg peak (max 5.31 cm) compared to the distal side (max 2.42 cm). In simulation, it was found that, for a pediatric brain, it is possible to use the technique to image a region

Bone Mineral Density across a Range of Physical Activity Volumes: NHANES 2007–2010

PubMed Central

Whitfield, Geoffrey P.; Kohrt, Wendy M.; Pettee Gabriel, Kelley K.; Rahbar, Mohammad H.; Kohl, Harold W.

2014-01-01

Introduction The association between aerobic physical activity volume and bone mineral density (BMD) is not completely understood. The purpose of this study was to clarify the association between BMD and aerobic activity across a broad range of activity volumes, in particular volumes between those recommended in the 2008 Physical Activity Guidelines for Americans and those of trained endurance athletes. Methods Data from the 2007–2010 National Health and Nutrition Examination Survey were used to quantify the association between reported physical activity and BMD at the lumbar spine and proximal femur across the entire range of activity volumes reported by US adults. Participants were categorized into multiples of the minimum guideline-recommended volume based on reported moderate and vigorous intensity leisure activity. Lumbar and proximal femur BMD was assessed with dual-energy x-ray absorptiometry. Results Among women, multivariable-adjusted linear regression analyses revealed no significant differences in lumbar BMD across activity categories, while proximal femur BMD was significantly higher among those who exceeded guidelines by 2–4 times than those who reported no activity. Among men, multivariable-adjusted BMD at both sites neared its highest values among those who exceeded guidelines by at least 4 times and was not progressively higher with additional activity. Logistic regression estimating the odds of low BMD generally echoed the linear regression results. Conclusion The association between physical activity volume and BMD is complex. Among women, exceeding guidelines by 2–4 times may be important for maximizing BMD at the proximal femur, while among men, exceeding guidelines by 4+ times may be beneficial for lumbar and proximal femur BMD. PMID:24870584

[Antioxidant activity of vegetable oils with various omega-6/omega-3 fatty acids ratio].

PubMed

Guseva, D A; Prozorovskaia, N N; Shironin, A V; Sanzhakov, M A; Evteeva, N M; Rusina, I F; Kasaikina, O T

2010-01-01

Antioxidant activity and the oxidative stability were investigated in flax, sesame, silybum oils and oils with different omega-6/omega-3 fatty acid ratio. The content of antioxidants (AO) in crude oils and their reactivity towards peroxyl radicals were studied using kinetic method for addition of oil in a model reaction of cumol oxidation. There were correlations between PUFA/omega-9 and thermal stability (50 degrees C); between gamma-tocopherol content and resistantance to oxidative changes after storage at (10 +/- 2) degrees C for 6 months.

R-carrying genotypes of serum paraoxonase (PON1) 192 polymorphism and higher activity ratio are related to susceptibility against ischemic stroke.

PubMed

Mahrooz, Abdolkarim; Gohari, Ghorban; Hashemi, Mohammad-Bagher; Zargari, Mehryar; Musavi, Hadis; Abedini, Mahmoud; Alizadeh, Ahad

2012-12-01

The polymorphic gene of serum paraoxonase (PON1) and its activity involved in atherosclerosis. The purpose of the study was to analyze PON1 192 Q/R polymorphism and the enzyme activities in ischemic stroke. The polymorphism as the most common polymorphism in PON1 gene coding sequence is associated with variation in the enzyme activity and vascular disease. The study included 85 stroke patients and 71 control subjects. PON1 192 polymorphism was genotyped using PCR protocol. Paraoxonase activity (Para) and arylesterase activity (Aryl) were determined spectrophotometrically using paraoxon and phenylacetate as the substrates. The QR and RR genotypes were more frequent in stroke population compared to controls, resulting in a higher frequency of the R allele in patients (0.24 vs 0.18, OR = 1.41). Patients had significantly higher Para/Aryl ratio than that of controls (P = 0.016). In stroke patients, Para/Aryl and Para/HDL ratios increased with this order: QQ < QR < RR. Hypertension significantly increased the risk of ischemic stroke by 15-fold among R-containing people, while this was significantly increased 4-fold for QQ homozygotes. Smoking increased the risk of having ischemic stroke in both QQ homozygote and QR + RR group (OR = 2.84 and OR = 2.33, respectively). In conclusion, these data highlight the importance of PON1 192 R allele and high Para/Aryl ratio in susceptibility to ischemic stroke in the population. The presence of the 192 R allele potentiates the risk of stroke especially in hypertensive people. Decreased Aryl and increased Para/Aryl, Para/HDL and Aryl/HDL ratios may be markers indicated the increased susceptibility to ischemic stroke in the population.

Coupling of the phosphatase activity of Ci-VSP to its voltage sensor activity over the entire range of voltage sensitivity

PubMed Central

Sakata, Souhei; Hossain, Md. Israil; Okamura, Yasushi

2011-01-01

Abstract The voltage sensing phosphatase Ci-VSP is composed of a voltage sensor domain (VSD) and a cytoplasmic phosphatase domain. Upon membrane depolarization, movement of the VSD triggers the enzyme's phosphatase activity. To gain further insight into its operating mechanism, we studied the PI(4,5)P2 phosphatase activity of Ci-VSP expressed in Xenopus oocytes over the entire range of VSD motion by assessing the activity of coexpressed Kir2.1 channels or the fluorescence signal from a pleckstrin homology domain fused with green fluorescent protein (GFP) (PHPLC-GFP). Both assays showed greater phosphatase activity at 125 mV than at 75 mV, which corresponds to ‘sensing’ charges that were 90% and 75% of maximum, respectively. On the other hand, the activity at 160 mV (corresponding to 98% of the maximum ‘sensing’ charge) was indistinguishable from that at 125 mV. Modelling the kinetics of the PHPLC-GFP fluorescence revealed that its time course was dependent on both the level of Ci-VSP expression and the diffusion of PHPLC-GFP beneath the plasma membrane. Enzyme activity was calculated by fitting the time course of PHPLC-GFP fluorescence into the model. The voltage dependence of the enzyme activity was superimposable on the Q–V curve, which is consistent with the idea that the enzyme activity is tightly coupled to VSD movement over the entire range of membrane potentials that elicit VSD movement. PMID:21486809

Dysfunctional long-range coordination of neural activity during Gestalt perception in schizophrenia.

PubMed

Uhlhaas, Peter J; Linden, David E J; Singer, Wolf; Haenschel, Corinna; Lindner, Michael; Maurer, Konrad; Rodriguez, Eugenio

2006-08-02

Recent theoretical and empirical research on schizophrenia converges on the notion that core aspects of the pathophysiology of the disorder may arise from a dysfunction in the coordination of distributed neural activity. Synchronization of neural responses in the beta-band (15-30 Hz) and gamma-band range (30-80 Hz) has been implicated as a possible neural substrate for dysfunctional coordination in schizophrenia. To test this hypothesis, we examined the electroencephalography (EEG) activity in 19 patients with a Diagnostic and Statistical Manual of Mental Disorder, edition IV criteria, diagnosis of schizophrenia and 19 healthy control subjects during a Gestalt perception task. EEG data were analyzed for phase synchrony and induced spectral power as an index of neural synchronization. Schizophrenia patients were impaired significantly in the detection of images that required the grouping of stimulus elements into coherent object representations. This deficit was accompanied by longer reaction times in schizophrenia patients. Deficits in Gestalt perception in schizophrenia patients were associated with reduced phase synchrony in the beta-band (20-30 Hz), whereas induced spectral power in the gamma-band (40-70 Hz) was mainly intact. Our findings suggest that schizophrenia patients are impaired in the long-range synchronization of neural responses, which may reflect a core deficit in the coordination of neural activity and underlie the specific cognitive dysfunctions associated with the disorder.

Sequential ranging integration times in the presence of CW interference in the ranging channel

NASA Technical Reports Server (NTRS)

Mathur, Ashok; Nguyen, Tien

1986-01-01

The Deep Space Network (DSN), managed by the Jet Propulsion Laboratory for NASA, is used primarily for communication with interplanetary spacecraft. The high sensitivity required to achieve planetary communications makes the DSN very susceptible to radio-frequency interference (RFI). In this paper, an analytical model is presented of the performance degradation of the DSN sequential ranging subsystem in the presence of downlink CW interference in the ranging channel. A trade-off between the ranging component integration times and the ranging signal-to-noise ratio to achieve a desired level of range measurement accuracy and the probability of error in the code components is also presented. Numerical results presented illustrate the required trade-offs under various interference conditions.

Use of polarization to improve signal to clutter ratio in an outdoor active imaging system

NASA Astrophysics Data System (ADS)

Fontoura, Patrick F.; Giles, Michael K.; Padilla, Denise D.

2005-08-01

This paper describes the methodology and presents the results of the design of a polarization-sensitive system used to increase the signal-to-clutter ratio in a robust outdoor structured lighting sensor that uses standard CCD camera technology. This lighting sensor is intended to be used on an autonomous vehicle, looking down to the ground and horizontal to obstacles in an 8 foot range. The kinds of surfaces to be imaged are natural and man-made, such as asphalt, concrete, dirt and grass. The main problem for an outdoor eye-safe laser imaging system is that the reflected energy from background clutter tends to be brighter than the reflected laser energy. A narrow-band optical filter does not reduce significantly the background clutter in bright sunlight, and problems also occur when the surface is highly absorptive, like asphalt. Therefore, most of applications are limited to indoor and controlled outdoor conditions. A series of measurements was made for each of the materials studied in order to find the best configuration for the polarizing system and also to find out the potential improvement in the signal-to-clutter ratio (STC). This process was divided into three parts: characterization of the reflected sunlight, characterization of the reflected laser light, and measurement of the improvement in the STC. The results show that by using polarization properties it is possible to design an optical system that is able to increase the signal-to-clutter ratio from approximately 30% to 100% in the imaging system, depending on the kind of surface and on the incidence angle of the sunlight. The technique was also analyzed for indoor use, with the background clutter being the room illumination. For this specific case, polarization did not improve the signal-to-clutter ratio.

Cinnamic acid-inhibited ribulose-1,5-bisphosphate carboxylase activity is mediated through decreased spermine and changes in the ratio of polyamines in cowpea.

PubMed

Huang, Xingxue; Bie, Zhilong

2010-01-01

This study investigated the effects of cinnamic acid (CA) on ribulose-1,5-bisphosphate carboxylase (RuBPC) activity and the endogenous polyamine levels of cowpea leaves. The results show that 0.1 mM CA treatment decreased photosynthetic rate (P(n)) and RuBPC activity, but it did not affect the maximal photochemical efficiency of PSII (F(v)/F(m)), the actual photochemical efficiency of PSII (PhiPSII), intercellular CO(2) concentration (C(i)), and relative chlorophyll content. These suggest that the decrease in P(n) is at least partially attributed to a lowered RuBPC activity. In addition, 0.1 mM CA treatment increased the putrescine (Put) level, but decreased spermidine (Spd) and spermine (Spm) levels, thereby reducing the (Spd+Spm)/Put (PAs) ratio in the leaves. The exogenous application of 1 mM Spd markedly reversed these CA-induced effects for polyamine and partially restored the PAs ratio and RuBPC activity in leaves. Methylglyoxal-bis (guanylhydrazone) (MGBG), which is an inhibitor of S-adenosylmethionine decarboxylase (SAMDC), results in the inability of activated cells to synthesize Spd and exacerbates the negative effects induced by CA. The exogenous application of 1 mM D-arginine (D-Arg), which is an inhibitor of Put biosynthesis, decreased the levels of Put, but increased the PAs ratio and RuBPC activity in leaves. These results suggest that 0.1 mM CA inhibits RuBPC activity by decreasing the levels of endogenous free and perchloric acid soluble (PS) conjugated Spm, as well as the PAs ratio.

Cervicocephalic kinesthetic sensibility, active range of cervical motion, and oculomotor function in patients with whiplash injury.

PubMed

Heikkilä, H V; Wenngren, B I

1998-09-01

To investigate cervicocephalic kinesthetic sensibility, active range of cervical motion, and oculomotor function in patients with whiplash injury. A 2-year review of consecutive patients admitted to the emergency unit after whiplash injury. An otorhinolaryngology department. Twenty-seven consecutive patients with diagnosed whiplash injury (14 men and 13 women, mean age, 33.8yrs [range, 18 to 66yrs]). The controls were healthy subjects without a history of whiplash injury. Oculomotor function was tested at 2 months and at 2 years after whiplash injury. The ability to appreciate both movement and head position was studied. Active range of cervical motion was measured. Subjective intensity of neck pain and major medical symptoms were recorded. Active head repositioning was significantly less precise in the whiplash subjects than in the control group. Failures in oculomotor functions were observed in 62% of subjects. Significant correlations occurred between smooth pursuit tests and active cervical range of motion. Correlations also were established between the oculomotor test and the kinesthetic sensibility test. The results suggest that restricted cervical movements and changes in the quality of proprioceptive information from the cervical spine region affect voluntary eye movements. A flexion/extension injury to the neck may result in dysfunction of the proprioceptive system. Oculomotor dysfunction after neck trauma might be related to cervical afferent input disturbances.

CD4/CD8 Ratio and KT Ratio Predict Yellow Fever Vaccine Immunogenicity in HIV-Infected Patients.

PubMed

Avelino-Silva, Vivian I; Miyaji, Karina T; Hunt, Peter W; Huang, Yong; Simoes, Marisol; Lima, Sheila B; Freire, Marcos S; Caiaffa-Filho, Helio H; Hong, Marisa A; Costa, Dayane Alves; Dias, Juliana Zanatta C; Cerqueira, Natalia B; Nishiya, Anna Shoko; Sabino, Ester Cerdeira; Sartori, Ana M; Kallas, Esper G

2016-12-01

HIV-infected individuals have deficient responses to Yellow Fever vaccine (YFV) and may be at higher risk for adverse events (AE). Chronic immune activation-characterized by low CD4/CD8 ratio or high indoleamine 2,3-dioxygenase-1 (IDO) activity-may influence vaccine response in this population. We prospectively assessed AE, viremia by the YFV virus and YF-specific neutralizing antibodies (NAb) in HIV-infected (CD4>350) and -uninfected adults through 1 year after vaccination. The effect of HIV status on initial antibody response to YFV was measured during the first 3 months following vaccination, while the effect on persistence of antibody response was measured one year following vaccination. We explored CD4/CD8 ratio, IDO activity (plasma kynurenine/tryptophan [KT] ratio) and viremia by Human Pegivirus as potential predictors of NAb response to YFV among HIV-infected participants with linear mixed models. 12 HIV-infected and 45-uninfected participants were included in the final analysis. HIV was not significantly associated with AE, YFV viremia or NAb titers through the first 3 months following vaccination. However, HIV-infected participants had 0.32 times the NAb titers observed for HIV-uninfected participants at 1 year following YFV (95% CI 0.13 to 0.83, p = 0.021), independent of sex, age and prior vaccination. In HIV-infected participants, each 10% increase in CD4/CD8 ratio predicted a mean 21% higher post-baseline YFV Nab titer (p = 0.024). Similarly, each 10% increase in KT ratio predicted a mean 21% lower post-baseline YFV Nab titer (p = 0.009). Viremia by Human Pegivirus was not significantly associated with NAb titers. HIV infection appears to decrease the durability of NAb responses to YFV, an effect that may be predicted by lower CD4/CD8 ratio or higher KT ratio.

Assessment of Non-Traditional Isotopic Ratios by Mass Spectrometry for Analysis of Nuclear Activities

DTIC Science & Technology

2016-03-01

Assessment of Non-traditional Isotopic Ratios by Mass Spectrometry for Analysis of Nuclear Activities Distribution Statement A. Approved for pubic...cubic meter (m 3 ) cubic foot (ft 3 ) 2.831 685 × 10 –2 cubic meter (m 3 ) Mass /Density pound (lb) 4.535 924 × 10 –1 kilogram (kg) unified...atomic mass unit (amu) 1.660 539 × 10 –27 kilogram (kg) pound- mass per cubic foot (lb ft –3 ) 1.601 846 × 10 1 kilogram per cubic meter (kg m –3

Chlorine Isotope Ratios in M Giants and S Stars

NASA Astrophysics Data System (ADS)

Maas, Zachary; Pilachowski, C. A.

2018-01-01

Chlorine is an odd-Z, light element that has been poorly studied in stars. Recently, the first stellar abundance measurements of the isotopologue 35Cl were made and the 35Cl/37Cl ratio was derived in RZ Ari (Maas et al. 2016). Additional abundance measurements are necessary to understand the Galactic chemical evolution and complex nucleosynthesis of Cl. The Cl isotope ratio in particular is important in distinguishing contributions from different nucleosynthesis sites to the surface abundances of stars. For example, current nucloesynthesis models predict that both isotopes of Cl are produced primarily during core collapse supernovae (CCSNe) with the energy and progenitor mass impacting the isotopic ratio of the ejected material. In addition to CCSNe, 37Cl is formed by the s-process both in massive stars and in AGB stars, and 35Cl may be produced from neutrino spallation. Understanding the formation of the Cl isotopes is also important to studies of the interstellar medium (ISM). A range of Cl isotope ratios mainly between 2 - 3.5 have been measured in star forming regions, in the circumstellar envelopes of evolved stars, and in proto-stellar cores using Cl bearing molecules. Additional measurements of the Cl isotope ratio in nearby stars will test nucleosynthesis models and allow comparisons with the range of isotope ratios observed in the ISM.We build on the results of Maas et al. (2016) by measuring the Cl isotope ratio in six M giants and four S stars using R~50,000 resolution spectra from Phoenix on Gemini South. We find no significant difference between the average Cl isotope ratios in the M stars and S stars and our measurements are consistent with the range of values seen in the ISM. We also find the average Cl ratio to be larger than the predicted isotope ratio of 1.8 for the solar neighborhood. Finally, two S stars, GG Pup and WY Pyx, show anomalously strong HCl features with equivalent widths ~3-5 times larger than the HCl features of other stars of

Numerical analysis of the effect of the kind of activating agent and the impregnation ratio on the parameters of the microporous structure of the active carbons

NASA Astrophysics Data System (ADS)

Kwiatkowski, Mirosław

2015-09-01

The paper presents the results of the research on the application of the LBET class adsorption models with the fast multivariant identification procedure as a tool for analysing the microporous structure of the active carbons obtained by chemical activation using potassium and sodium hydroxides as an activator. The proposed technique of the fast multivariant fitting of the LBET class models to the empirical adsorption data was employed particularly to evaluate the impact of the used activator and the impregnation ratio on the obtained microporous structure of the carbonaceous adsorbents.

The Black Hole Masses and Eddington Ratios of Type 2 Quasars

NASA Astrophysics Data System (ADS)

Kong, Minzhi; Ho, Luis C.

2018-06-01

Type 2 quasars are an important constituent of active galaxies, possibly representing the evolutionary precursors of traditionally studied type 1 quasars. We characterize the black hole (BH) mass (M BH) and Eddington ratio (L bol/L Edd) for 669 type 2 quasars selected from the Sloan Digital Sky Survey, using BH masses estimated from the M BH–σ * relation and bolometric corrections scaled from the extinction-corrected [O III] λ5007 luminosity. When stellar velocity dispersions cannot be measured directly from the spectra, we estimate them from the core velocity dispersions of the narrow emission lines [O II] λλ3726, 3729, [S II] λλ6716, 6731, and [O III] λ5007, which are shown to trace the gravitational potential of the stars. Energy input from the active nucleus still imparts significant perturbations to the gas kinematics, especially to high-velocity, blueshifted wings. Nonvirial motions in the gas become most noticeable in systems with high Eddington ratios. The BH masses of our sample of type 2 quasars range from M BH ≈ 106.5 to 1010.4 M ⊙ (median 108.2 M ⊙). Type 2 quasars have characteristically large Eddington ratios (L bol/L Edd ≈ 10‑2.9–101.8 median 10‑0.7), slightly higher than in type 1 quasars of similar redshift; the luminosities of ∼20% of the sample formally exceed the Eddington limit. The high Eddington ratios may be consistent with the notion that obscured quasars evolve into unobscured quasars.

Functional importance of short-range binding and long-range solvent interactions in helical antifreeze peptides.

PubMed

Ebbinghaus, Simon; Meister, Konrad; Prigozhin, Maxim B; Devries, Arthur L; Havenith, Martina; Dzubiella, Joachim; Gruebele, Martin

2012-07-18

Short-range ice binding and long-range solvent perturbation both have been implicated in the activity of antifreeze proteins and antifreeze glycoproteins. We study these two mechanisms for activity of winter flounder antifreeze peptide. Four mutants are characterized by freezing point hysteresis (activity), circular dichroism (secondary structure), Förster resonance energy transfer (end-to-end rigidity), molecular dynamics simulation (structure), and terahertz spectroscopy (long-range solvent perturbation). Our results show that the short-range model is sufficient to explain the activity of our mutants, but the long-range model provides a necessary condition for activity: the most active peptides in our data set all have an extended dynamical hydration shell. It appears that antifreeze proteins and antifreeze glycoproteins have reached different evolutionary solutions to the antifreeze problem, utilizing either a few precisely positioned OH groups or a large quantity of OH groups for ice binding, assisted by long-range solvent perturbation. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Some Effects of Sweep and Aspect Ratio on the Transonic Flutter Characteristics of a Series of Thin Cantilever Wings Having a Taper Ratio of 0.6

NASA Technical Reports Server (NTRS)

Jones, G. W., Jr.; Unangst, J. R.

1963-01-01

An investigation of the flutter characteristics of a series of thin cantilever wings having taper ratios of 0.6 was conducted in the Langley transonic blowdown tunnel at Mach numbers between 0.76 and 1.42. The angle of sweepback was varied from 0 degrees to 60 degrees on wings of aspect ratio 4, and the aspect ratio was varied from 2.4 to 6.4 on wings with 45 degrees of sweepback. The results are presented as ratios between the experimental flutter speeds and the reference flutter speeds calculated on the basis of incompressible two-dimensional flow. These ratios, designated the flutter-speed ratios, are given as functions of Mach number for the various wings. The flutter-speed ratios were characterized, in most cases, by values near 1.0 at subsonic speeds with large increases in the speed ratios in the range of supersonic speeds investigated. Increasing the sweep effected increases in the flutter-speed ratios between 0 degrees and 30 degrees followed by progressive reductions of the speed ratios to nearly 1.0 as the sweep was increased from 30 degrees to 60 degrees. Reducing the aspect ratio from 6.4 to 2.4 resulted in progressively larger values of the flutter-speed ratios throughout the Mach number range investigated.

Effect of Jet-nozzle-expansion Ratio on Drag of Parabolic Afterbodies

NASA Technical Reports Server (NTRS)

Englert, Gerald W; Vargo, Donald J; Cubbison, Robert W

1954-01-01

The interaction of the flow from one convergent and two convergent-divergent nozzles on parabolic afterbodies was studied at free-stream Mach numbers of 2.0, 1.6, and 0.6 over a range of jet pressure ratio. The influence of the jet on boattail and base drag was very pronounced. Study of the total external afterbody drag values at supersonic speeds indicated that, over most of the high-pressure-ratio range, increasing the nozzle design expansion ratio increased the drag even though the boattail area was reduced. Increasing the pressure ratio tended to increase slightly the total-drag increment caused by angle-of-attack operation.

New criteria for measuring range management activities.

Treesearch

T.M. Quigley; D.S. Dillard; J.B. [and others] Reese

1989-01-01

The USDA Forest Service national range program is currently evaluating its information needs at the national level A Range Measurement Task Group of Agency personnel was assembled in January 1988 to evaluate the information needs and recommend appropriate measures and reports. This document is the final recommendation of the task group. The recommendation includes...

Quantifying in situ growth rate of a filamentous bacterial species in activated sludge using rRNA:rDNA ratio.

PubMed

Nguyen, Vivi L; He, Xia; de Los Reyes, Francis L

2016-11-01

If the in situ growth rate of filamentous bacteria in activated sludge can be quantified, researchers can more accurately assess the effect of operating conditions on the growth of filaments and improve the mathematical modeling of filamentous bulking. We developed a method to quantify the in situ specific growth rate of Sphaerotilus natans (a model filament) in activated sludge using the species-specific 16S rRNA:rDNA ratio. Primers targeting the 16S rRNA of S. natans were designed, and real-time PCR and RT-PCR were used to quantify DNA and RNA levels of S. natans, respectively. A positive linear relationship was found between the rRNA:rDNA ratio (from 440 to 4500) and the specific growth rate of S. natans (from 0.036 to 0.172 h -1 ) using chemostat experiments. The in situ growth rates of S. natans in activated sludge samples from three water reclamation facilities were quantified, illustrating how the approach can be applied in a complex environment such as activated sludge. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

An overview of the laser ranging method of space laser altimeter

NASA Astrophysics Data System (ADS)

Zhou, Hui; Chen, Yuwei; Hyyppä, Juha; Li, Song

2017-11-01

Space laser altimeter is an active remote sensing instrument to measure topographic map of Earth, Moon and planetary. The space laser altimeter determines the range between the instrument and laser footprint by measuring round trip time of laser pulse. The return pulse reflected from ground surface is gathered by the receiver of space laser altimeter, the pulsewidth and amplitude of which are changeable with the variability of the ground relief. Meantime, several kinds of noise overlapped on the return pulse signal affect its signal-to-noise ratio. To eliminate the influence of these factors that cause range walk and range uncertainty, the reliable laser ranging methods need to be implemented to obtain high-precision range results. Based on typical space laser altimeters in the past few decades, various ranging methods are expounded in detail according to the operational principle of instruments and timing method. By illustrating the concrete procedure of determining time of flight of laser pulse, this overview provides the comparison of the employed technologies in previous and undergoing research programs and prospect innovative technology for space laser altimeters in future.

Noise and range considerations for close-range radar sensing of life signs underwater.

PubMed

Hafner, Noah; Lubecke, Victor

2011-01-01

Close-range underwater sensing of motion-based life signs can be performed with low power Doppler radar and ultrasound techniques. Corresponding noise and range performance trade-offs are examined here, with regard to choice of frequency and technology. The frequency range examined includes part of the UHF and microwave spectrum. Underwater detection of motion by radar in freshwater and saltwater are demonstrated. Radar measurements exhibited reduced susceptibility to noise as compared to ultrasound. While higher frequency radar exhibited better signal to noise ratio, propagation was superior for lower frequencies. Radar detection of motion through saltwater was also demonstrated at restricted ranges (1-2 cm) with low power transmission (10 dBm). The results facilitate the establishment of guidelines for optimal choice in technology for the underwater measurement motion-based life signs, with respect to trade offs involving range and noise.

The temperature dependence of the BK channel activity - kinetics, thermodynamics, and long-range correlations.

PubMed

Wawrzkiewicz-Jałowiecka, Agata; Dworakowska, Beata; Grzywna, Zbigniew J

2017-10-01

Large-conductance, voltage dependent, Ca 2+ -activated potassium channels (BK) are transmembrane proteins that regulate many biological processes by controlling potassium flow across cell membranes. Here, we investigate to what extent temperature (in the range of 17-37°C with ΔT=5°C step) is a regulating parameter of kinetic properties of the channel gating and memory effect in the series of dwell-time series of subsequent channel's states, at membrane depolarization and hyperpolarization. The obtained results indicate that temperature affects strongly the BK channels' gating, but, counterintuitively, it exerts no effect on the long-range correlations, as measured by the Hurst coefficient. Quantitative differences between dependencies of appropriate channel's characteristics on temperature are evident for different regimes of voltage. Examining the characteristics of BK channel activity as a function of temperature allows to estimate the net activation energy (E act ) and changes of thermodynamic parameters (ΔH, ΔS, ΔG) by channel opening. Larger E act corresponds to the channel activity at membrane hyperpolarization. The analysis of entropy and enthalpy changes of closed to open channel's transition suggest the entropy-driven nature of the increase of open state probability during voltage activation and supports the hypothesis about the voltage-dependent geometry of the channel vestibule. Copyright © 2017 Elsevier B.V. All rights reserved.

Experimental study of low aspect ratio compressor blading

NASA Technical Reports Server (NTRS)

Reid, L.; Moore, R. D.

1979-01-01

The effects of low aspect ratio blading on aerodynamic performance were examined. Four individual transonic compressor stages, representative of the inlet stage of an advanced high pressure ratio core compressor, are discussed. The flow phenomena for the four stages are investigated. Comparisons of blade element parameters are presented for the two different aspect ratio configurations. Blade loading levels are compared for the near stall conditions and comparisons are made of loss and diffusion factors over the operating range of incidence angles.

The activity ratio of 228Th to 228Ra in bone tissue of recently deceased humans: a new dating method in forensic examinations.

PubMed

Zinka, Bettina; Kandlbinder, Robert; Schupfner, Robert; Haas, Gerald; Wolfbeis, Otto S; Graw, Matthias

2012-01-01

Reliable determination of time since death in human skeletons or single bones often is limited by methodically difficulties. Determination of the specific activity ratio of natural radionuclides, in particular of 232Th (Thorium), 228Th and 228Ra (Radium) seems to be a new appropriate method to calculate the post mortem interval. These radionuclides are incorporated by any human being, mainly from food. So with an individual's death the uptake of radionuclides ends. But the decay of 232Th produces 228Ra and 228Th due to its decay series, whereas 228Th is continuously built up in the human's bones. Thus, it can be concluded that in all deceased humans at different times after death different activity ratios of 228Th to 228Ra will develop in bone. According to this fact it should be possible to calculate time since death of an individual by first analysing the specific activities of 228Th and 228Ra in bones of deceased and then determining the 228Th/228Ra activity ratio, which can be assigned to a certain post-mortem interval.

Performance and activated sludge characteristics at short solid retention time in a submerged MBR: effects of C/N ratio of wastewater.

PubMed

Sari Erkan, Hanife; Onkal Engin, Guleda

2018-02-22

This study investigated the effect of carbon to nitrogen (C/N) ratio of influent wastewater on performance and activated sludge properties at a sludge retention time of 5 d in a submerged membrane bioreactor. The chemical oxygen demand and ammonia-Nitrogen (NH 3 -N) removal efficiencies were found to be over 96.3% and 86.9% in the sMBRs having different C/N ratios. It was found that total extracellular polymeric substances and total soluble microbial products increased with an increase in C/N ratio. It was also observed that critical flux, relative hydrophobicity and zeta potential values decreased, and capillary suction time, particle size and viscosity of sludge increased as the C/N ratio increased.

Hydrothermal monitoring in a quiescent volcanic arc: Cascade Range, northwestern United States

USGS Publications Warehouse

Ingebritsen, S.E.; Randolph-Flagg, N. G.; Gelwick, K.D.; Lundstrom, E.A.; Crankshaw, I.M.; Murveit, A.M.; Schmidt, M.E.; Bergfeld, D.; Spicer, K.R.; Tucker, D.S.; Mariner, R.H.; Evans, William C.

2014-01-01

Ongoing (1996–present) volcanic unrest near South Sister, Oregon, is accompanied by a striking set of hydrothermal anomalies, including elevated temperatures, elevated major ion concentrations, and 3He/4He ratios as large as 8.6 RA in slightly thermal springs. These observations prompted the US Geological Survey to begin a systematic hydrothermal-monitoring effort encompassing 25 sites and 10 of the highest-risk volcanoes in the Cascade volcanic arc, from Mount Baker near the Canadian border to Lassen Peak in northern California. A concerted effort was made to develop hourly, multiyear records of temperature and/or hydrothermal solute flux, suitable for retrospective comparison with other continuous geophysical monitoring data. Targets included summit fumarole groups and springs/streams that show clear evidence of magmatic influence in the form of high 3He/4He ratios and/or anomalous fluxes of magmatic CO2 or heat. As of 2009–2012, summit fumarole temperatures in the Cascade Range were generally near or below the local pure water boiling point; the maximum observed superheat was 3 during periods of hourly record. Hydrothermal responses to these small seismic stimuli were generally undetectable or ambiguous. Evaluation of multiyear to multidecadal trends indicates that whereas the hydrothermal system at Mount St. Helens is still fast-evolving in response to the 1980–present eruptive cycle, there is no clear evidence of ongoing long-term trends in hydrothermal activity at other Cascade Range volcanoes that have been active or restless during the past century (Baker, South Sister, and Lassen). Experience gained during the Cascade Range hydrothermal-monitoring experiment informs ongoing efforts to capture entire unrest cycles at more active but generally less accessible volcanoes such as those in the Aleutian arc.

Assessing nursing staffing ratios: variability in workload intensity.

PubMed

Upenieks, Valda V; Kotlerman, Jenny; Akhavan, Jaleh; Esser, Jennifer; Ngo, Myha J

2007-02-01

In 2004, California became the first state to implement specific nurse-to-patient ratios for all hospitals. These mandated enactments have caused significant controversy among health care professionals as well as nursing unions and professional organizations. Supporters of minimum nurse-to-patient ratios cite patient care quality, safety, and outcomes, whereas critics point to the lack of solid data and the use of a universally standardized acuity tool. Much more remains to be learned about staffing policies before mature links may be made regarding set staffing ratios and patient outcomes - specifically, how nurses spend their time in terms of variability in their daily work. This study examines two comparable telemetry units with a 1:3 staffing ratio within a California hospital system to determine the relative rates of variability in nursing activities. The results demonstrate significant differences in categorical nursing activities (e.g., direct care, indirect care, etc.) between the two telemetry units (chi(2) = 91.2028; p < or = .0001). No correlation was noted between workload categories with daily staffing ratios and staffing mix between the two units. Although patients were grouped in a similar telemetry classification category and care was mandated at a set ratio, patient needs were variable, creating a significant difference in registered nurse (RN) categorical activities on the two units.

Fe/O ratio behavior as an indicator of solar plasma state at different solar activity manifestations and in periods of their absence

NASA Astrophysics Data System (ADS)

Minasyants, Gennady; Minasyants, Tamara; Tomozov, Vladimir

2018-03-01

We report the results of the investigation into plasma physical characteristics at various solar activity manifestations and in periods of their absence. These results have been obtained from quantitative estimates of the relative abundance of Fe/O ions in different energy ranges. Maximum values of the Fe/O ratio is shown to correspond to particle fluxes from impulsive flares for ions with energies <2 MeV/n (the most significant manifestation of the FIP effect). In particle fluxes from gradual flares, the Fe/O value decreases smoothly with ion energy and is noticeably inferior to values of fluxes in impulsive events. We have established that the properties of flares of solar cosmic rays indicate their belonging to a separate subclass in the total population of gradual events. Relying on variations in the abundance of Fe/O ions, we propose an explanation of the solar plasma behavior during the development of flares of both classes. Magnetic clouds (a separate type of coronal mass ejections (CME)), which have regions of turbulent compression and are sources of strong geomagnetic storms, exhibit a relative composition of Fe ions comparable to the abundance of Fe in ion fluxes from gradual flares. We have found out that the Fe/O value can be used to detect penetration of energetic flare plasma into the CME body at the initial phase of their joint development and to estimate its relative contribution. During solar minimum with the complete absence of sunspots, the Fe/O ratio during periods of "quiet" solar wind show absolutely low values of Fe/O=0.004-0.010 in the energy range from 2-5 to 30 MeV/n. This is associated with the manifestation of the cosmic ray anomalous component, which causes an increase in the intensity of ion fluxes with a high first ionization potential, including oxygen (O), and elements with a low first ionization potential (Fe) demonstrate the weakening of the fluxes. As for particles with higher energies (Ek>30 MeV/n), the Fe/O increase is due to

Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model

NASA Astrophysics Data System (ADS)

Martin, Elliot; Shreim, Amer; Paczuski, Maya

2010-01-01

We define an activity-dependent branching ratio that allows comparison of different time series Xt . The branching ratio bx is defined as bx=E[ξx/x] . The random variable ξx is the value of the next signal given that the previous one is equal to x , so ξx={Xt+1∣Xt=x} . If bx>1 , the process is on average supercritical when the signal is equal to x , while if bx<1 , it is subcritical. For stock prices we find bx=1 within statistical uncertainty, for all x , consistent with an “efficient market hypothesis.” For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, bx is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where bx≃1 , which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for Xt and for ξx . For the BTW model the distribution of ξx is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x . Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where bx is close to one disappears once bulk dissipation is introduced in the BTW model—supporting our hypothesis that it is an indicator of criticality.

Activity-dependent branching ratios in stocks, solar x-ray flux, and the Bak-Tang-Wiesenfeld sandpile model.

PubMed

Martin, Elliot; Shreim, Amer; Paczuski, Maya

2010-01-01

We define an activity-dependent branching ratio that allows comparison of different time series X(t). The branching ratio b(x) is defined as b(x)=E[xi(x)/x]. The random variable xi(x) is the value of the next signal given that the previous one is equal to x, so xi(x)=[X(t+1) | X(t)=x]. If b(x)>1, the process is on average supercritical when the signal is equal to x, while if b(x)<1, it is subcritical. For stock prices we find b(x)=1 within statistical uncertainty, for all x, consistent with an "efficient market hypothesis." For stock volumes, solar x-ray flux intensities, and the Bak-Tang-Wiesenfeld (BTW) sandpile model, b(x) is supercritical for small values of activity and subcritical for the largest ones, indicating a tendency to return to a typical value. For stock volumes this tendency has an approximate power-law behavior. For solar x-ray flux and the BTW model, there is a broad regime of activity where b(x) approximately equal 1, which we interpret as an indicator of critical behavior. This is true despite different underlying probability distributions for X(t) and for xi(x). For the BTW model the distribution of xi(x) is Gaussian, for x sufficiently larger than 1, and its variance grows linearly with x. Hence, the activity in the BTW model obeys a central limit theorem when sampling over past histories. The broad region of activity where b(x) is close to one disappears once bulk dissipation is introduced in the BTW model-supporting our hypothesis that it is an indicator of criticality.

Ranging, Activity and Habitat Use by Tigers in the Mangrove Forests of the Sundarban.

PubMed

Naha, Dipanjan; Jhala, Yadvendradev V; Qureshi, Qamar; Roy, Manjari; Sankar, Kalyansundaram; Gopal, Rajesh

2016-01-01

The Sundarban of India and Bangladesh (about 6000 km²) are the only mangrove forests inhabited by a sizeable population of tigers. The adjoining area also supports one of the highest human densities and experiences severe human-tiger conflicts. We used GPS-Satellite and VHF radio-collars on 6 (3 males and 3 female) tigers to study their ranging patterns and habitat preference. The average home range (95% Fixed Kernel) for resident females was 56.4 (SE 5.69) and for males it was 110 (SE 49) km². Tigers crossed an average of 5 water channels > 30 meters per day with a mean width of 54 meters, whereas channels larger than 400 meters were rarely crossed. Tigers spent over 58% of their time within Phoenix habitat but compositional analysis showed a habitat preference of the order Avicennia-Sonneratia > Phoenix > Ceriops > Barren > Water. Average daily distance moved was 4.6 km (range 0.1-23). Activity of tigers peaked between 05:00 hours and 10:00 hours showing some overlap with human activity. Territory boundaries were demarcated by large channels which tigers intensively patrolled. Extra caution should be taken while fishing or honey collection during early morning in Avicennia-Sonneratia and Phoenix habitat types along wide channels to reduce human-tiger conflict. Considering home-range core areas as exclusive, tiger density was estimated at 4.6 (SE range 3.6 to 6.7) tigers/100 km2 giving a total population of 76 (SE range 59-110) tigers in the Indian Sundarban. Reluctance of tigers to cross wide water channels combined with increasing commercial boat traffic and sea level rise due to climate change pose a real threat of fragmenting the Sundarban tiger population.

Ranging, Activity and Habitat Use by Tigers in the Mangrove Forests of the Sundarban

PubMed Central

Naha, Dipanjan; Jhala, Yadvendradev V.; Qureshi, Qamar; Roy, Manjari; Sankar, Kalyansundaram; Gopal, Rajesh

2016-01-01

The Sundarban of India and Bangladesh (about 6000 km²) are the only mangrove forests inhabited by a sizeable population of tigers. The adjoining area also supports one of the highest human densities and experiences severe human-tiger conflicts. We used GPS-Satellite and VHF radio-collars on 6 (3 males and 3 female) tigers to study their ranging patterns and habitat preference. The average home range (95% Fixed Kernel) for resident females was 56.4 (SE 5.69) and for males it was 110 (SE 49) km². Tigers crossed an average of 5 water channels > 30 meters per day with a mean width of 54 meters, whereas channels larger than 400 meters were rarely crossed. Tigers spent over 58% of their time within Phoenix habitat but compositional analysis showed a habitat preference of the order Avicennia-Sonneratia > Phoenix > Ceriops > Barren > Water. Average daily distance moved was 4.6 km (range 0.1–23). Activity of tigers peaked between 05:00 hours and 10:00 hours showing some overlap with human activity. Territory boundaries were demarcated by large channels which tigers intensively patrolled. Extra caution should be taken while fishing or honey collection during early morning in Avicennia-Sonneratia and Phoenix habitat types along wide channels to reduce human-tiger conflict. Considering home-range core areas as exclusive, tiger density was estimated at 4.6 (SE range 3.6 to 6.7) tigers/100 km2 giving a total population of 76 (SE range 59–110) tigers in the Indian Sundarban. Reluctance of tigers to cross wide water channels combined with increasing commercial boat traffic and sea level rise due to climate change pose a real threat of fragmenting the Sundarban tiger population. PMID:27049644

Arm position influences the activation patterns of trunk muscles during trunk range-of-motion movements.

PubMed

Siu, Aaron; Schinkel-Ivy, Alison; Drake, Janessa Dm

2016-10-01

To understand the activation patterns of the trunk musculature, it is also important to consider the implications of adjacent structures such as the upper limbs, and the muscles that act to move the arms. This study investigated the effects of arm positions on the activation patterns and co-activation of the trunk musculature and muscles that move the arm during trunk range-of-motion movements (maximum trunk axial twist, flexion, and lateral bend). Fifteen males and fifteen females, asymptomatic for low back pain, performed maximum trunk range-of-motion movements, with three arm positions for axial twist (loose, crossed, abducted) and two positions for flexion and lateral bend (loose, crossed). Electromyographical data were collected for eight muscles bilaterally, and activation signals were cross-correlated between trunk muscles and the muscles that move the arms (upper trapezius, latissimus dorsi). Results revealed consistently greater muscle co-activation (higher cross-correlation coefficients) between the trunk muscles and upper trapezius for the abducted arm position during maximum trunk axial twist, while results for the latissimus dorsi-trunk pairings were more dependent on the specific trunk muscles (either abdominal or back) and latissimus dorsi muscle (either right or left side), as well as the range-of-motion movement. The findings of this study contribute to the understanding of interactions between the upper limbs and trunk, and highlight the influence of arm positions on the trunk musculature. In addition, the comparison of the present results to those of individuals with back or shoulder conditions may ultimately aid in elucidating underlying mechanisms or contributing factors to those conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of area ratio on the performance of a 5.5:1 pressure ratio centrifugal impeller

NASA Technical Reports Server (NTRS)

Schumann, L. F.; Clark, D. A.; Wood, J. R.

1986-01-01

A centrifugal impeller which was initially designed for a pressure ratio of approximately 5.5 and a mass flow rate of 0.959 kg/sec was tested with a vaneless diffuser for a range of design point impeller area ratios from 2.322 to 2.945. The impeller area ratio was changed by successively cutting back the impeller exit axial width from an initial value of 7.57 mm to a final value of 5.97 mm. In all, four separate area ratios were tested. For each area ratio a series of impeller exit axial clearances was also tested. Test results are based on impeller exit surveys of total pressure, total temperature, and flow angle at a radius 1.115 times the impeller exit radius. Results of the tests at design speed, peak efficiency, and an exit tip clearance of 8 percent of exit blade height show that the impeller equivalent pressure recovery coefficient peaked at a design point area ratio of approximately 2.748 while the impeller aerodynamic efficiency peaked at a lower value of area ratio of approximately 2.55. The variation of impeller efficiency with clearance showed expected trends with a loss of approximately 0.4 points in impeller efficiency for each percent increase in exit axial tip clearance for all impellers tested.

Measurement of the temperature coefficient of ratio transformers

NASA Technical Reports Server (NTRS)

Briggs, Matthew E.; Gammon, Robert W.; Shaumeyer, J. N.

1993-01-01

We have measured the temperature coefficient of the output of several ratio transformers at ratios near 0.500,000 using an ac bridge and a dual-phase, lock-in amplifier. The two orthogonal output components were each resolved to +/- ppb of the bridge drive signal. The results for three commercial ratio transformers between 20 and 50 C range from 0.5 to 100 ppb/K for the signal component in phase with the bridge drive, and from 4 to 300 ppb/K for the quadrature component.

Association of dietary pattern and physical activity level with triglyceride to high-density lipoprotein cholesterol ratio among adults in Jiangsu, China: a cross-sectional study with sex-specific differences.

PubMed

Lyu, Shurong; Su, Jian; Xiang, Quanyong; Wu, Ming

2014-08-01

Our study aims to explore the association between dietary patterns and physical activity levels (PAL) with a triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio, and to examine whether the association is sex dependent among Chinese adults. In this cross-sectional study, data were collected through questionnaires, anthropometric measurement, and biochemical tests. Four food patterns ("meat," "healthy," "high-energy," and "traditional Chinese") were established through factor analysis. Physical activity level was categorized as "active," "moderate," and "inactive." Logistic regression models were used to determine the associations between food patterns and PAL with TG/HDL-C ratio. Compared with quartile 1, quartiles 2 and 3 of meat pattern among men were found to be associated with lower risk of high TG/HDL-C ratio (the highest quartile of TG/HDL-C ratio). Similar decreased risk of high TG/HDL-C ratio was also observed in the highest quartile 4 of healthy pattern among women. Active PAL was protective against high TG/HDL-C ratio among both men (odds ratio [OR], 0.69; 95% confidence interval [CI], 0.55-0.86) and women (OR, 0.77; 95% CI, 0.62-0.96). Although no statistically significant interaction was observed, we found that individuals with active PAL and low healthy diet had a similar OR with those with inactive PAL and high healthy diet (0.62 vs 0.68). In conclusion, dietary patterns were associated with TG/HDL-C ratio in a sex-specific way, and active PAL was consistently related to decreased risk of high TG/HDL-C ratio across genders. Copyright © 2014 Elsevier Inc. All rights reserved.

Classification of nine malathion emulsion samples by using carbon isotope ratios and the ratio of organic solvents.

PubMed

Suto, Nana; Kawashima, Hiroto

2017-01-01

The compound specific isotope analysis is nowadays an important and powerful tool in geochemical, environmental and forensics field. On November 2013, Aqli Foods Corporation in Japan dealt with complaints about stench from frozen foods produced. Subsequently, very high concentrations of organophosphorus pesticide as malathion, ethylbenzene and xylene were detected in recovered frozen foods. In particular case, we present the method to measure the stable carbon isotope ratio (δ 13 C) of nine malathion emulsion pesticides using gas chromatography/isotope ratio mass spectrometry (GC/IRMS) to identify the source. The δ 13 C values of malathion ranged from -30.6‰ to -29.5‰. Because malathion used in all malathion emulsions sold in Japan is imported from the same overseas company, Cheminova, Denmark. The δ 13 C values of ethylbenzene ranged from -28.2‰ to -20.8‰ and those of m,p-xylene from -28.7‰ to -25.2‰. The differences in the δ 13 C values may be because of the material itself and chemical processing. We also determined the ratio of ethylbenzene to m,p-xylene and finally categorized the nine malathion samples into five groups on the basis of this ratio and the δ 13 C values of ethylbenzene and m,p-xylene. The results of isotopic fractionation during volatilization (refrigerate, room temperature and incubator) was negligible small. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

The effect of exercise mode and intensity of sub-maximal physical activities on salivary testosterone to cortisol ratio and α-amylase in young active males

PubMed Central

AZARBAYJANI, MOHAMMAD ALI; FATOLAHI, HOSEYN; RASAEE, MOHAMMAD JAVAD; PEERI, MAGHSOD; BABAEI, ROHOLAH

2011-01-01

We examined the effect of exercise intensity and mode on the acute responses of free testosterone to cortisol ratio and salivary α-amylase. We also evaluated the relationship between cortisol and salivary α-amylase. Ten healthy young active males participated voluntarily in this study in six single sessions. They exercised on a cycle ergo meter, treadmill, and elliptical instrument at intensities of 70% and 85% maximum heart rate for 25 minutes. Saliva samples were collected 5 minutes before and 5 minutes after each exercise session. No significant changes were observed for cortisol. Free testosterone to cortisol ratio increased during each exercise session (F5, 45=3.15, P=0.02). However, these changes are only significant after exercise on the treadmill at 70% maximum heart rate (t=2.94, P=0.02) and 85% maximum heart rate (t=0.53, P=0.03). Salivary α-amylase significantly varied among exercise sessions (F5, 45=3.97, P=0.005), and a significant decline was observed after exercise on the elliptical instrument (t=2.38, P=0.04) and treadmill (t=3.55, P=0.006) at 85% maximum heart rate. We found that the free testosterone to cortisol ratio is dependent on the exercise mode, while the salivary α-amylase response is dependent on the intensity of exercise. The increase of free testosterone to cortisol ratio in this study may indicate lower physiological stress in response to performing these exercises. Applying muscular strength with moderate intensity weight-bearing exercises possibly activates the anabolic pathways. Although the cortisol and salivary α-amylase responses were opposite in the majority of the exercise sessions, no significant inverse relationship was observed. PMID:27182369

The effect of exercise mode and intensity of sub-maximal physical activities on salivary testosterone to cortisol ratio and α-amylase in young active males.

PubMed

Azarbayjani, Mohammad Ali; Fatolahi, Hoseyn; Rasaee, Mohammad Javad; Peeri, Maghsod; Babaei, Roholah

We examined the effect of exercise intensity and mode on the acute responses of free testosterone to cortisol ratio and salivary α-amylase. We also evaluated the relationship between cortisol and salivary α-amylase. Ten healthy young active males participated voluntarily in this study in six single sessions. They exercised on a cycle ergo meter, treadmill, and elliptical instrument at intensities of 70% and 85% maximum heart rate for 25 minutes. Saliva samples were collected 5 minutes before and 5 minutes after each exercise session. No significant changes were observed for cortisol. Free testosterone to cortisol ratio increased during each exercise session (F 5, 45 =3.15, P=0.02) . However, these changes are only significant after exercise on the treadmill at 70% maximum heart rate ( t=2.94, P=0.02 ) and 85% maximum heart rate ( t=0.53, P=0.03 ). Salivary α-amylase significantly varied among exercise sessions (F 5, 45 =3.97, P=0.005), and a significant decline was observed after exercise on the elliptical instrument (t=2.38, P=0.04) and treadmill ( t=3.55, P=0.006 ) at 85% maximum heart rate. We found that the free testosterone to cortisol ratio is dependent on the exercise mode, while the salivary α-amylase response is dependent on the intensity of exercise. The increase of free testosterone to cortisol ratio in this study may indicate lower physiological stress in response to performing these exercises. Applying muscular strength with moderate intensity weight-bearing exercises possibly activates the anabolic pathways. Although the cortisol and salivary α-amylase responses were opposite in the majority of the exercise sessions, no significant inverse relationship was observed.

Quantifying asymmetry: ratios and alternatives.

PubMed

Franks, Erin M; Cabo, Luis L

2014-08-01

Traditionally, the study of metric skeletal asymmetry has relied largely on univariate analyses, utilizing ratio transformations when the goal is comparing asymmetries in skeletal elements or populations of dissimilar dimensions. Under this approach, raw asymmetries are divided by a size marker, such as a bilateral average, in an attempt to produce size-free asymmetry indices. Henceforth, this will be referred to as "controlling for size" (see Smith: Curr Anthropol 46 (2005) 249-273). Ratios obtained in this manner often require further transformations to interpret the meaning and sources of asymmetry. This model frequently ignores the fundamental assumption of ratios: the relationship between the variables entered in the ratio must be isometric. Violations of this assumption can obscure existing asymmetries and render spurious results. In this study, we examined the performance of the classic indices in detecting and portraying the asymmetry patterns in four human appendicular bones and explored potential methodological alternatives. Examination of the ratio model revealed that it does not fulfill its intended goals in the bones examined, as the numerator and denominator are independent in all cases. The ratios also introduced strong biases in the comparisons between different elements and variables, generating spurious asymmetry patterns. Multivariate analyses strongly suggest that any transformation to control for overall size or variable range must be conducted before, rather than after, calculating the asymmetries. A combination of exploratory multivariate techniques, such as Principal Components Analysis, and confirmatory linear methods, such as regression and analysis of covariance, appear as a promising and powerful alternative to the use of ratios. © 2014 Wiley Periodicals, Inc.

A CRISPR-Cas9 sex-ratio distortion system for genetic control

PubMed Central

Galizi, Roberto; Hammond, Andrew; Kyrou, Kyros; Taxiarchi, Chrysanthi; Bernardini, Federica; O’Loughlin, Samantha M.; Papathanos, Philippos-Aris; Nolan, Tony; Windbichler, Nikolai; Crisanti, Andrea

2016-01-01

Genetic control aims to reduce the ability of insect pest populations to cause harm via the release of modified insects. One strategy is to bias the reproductive sex ratio towards males so that a population decreases in size or is eliminated altogether due to a lack of females. We have shown previously that sex ratio distortion can be generated synthetically in the main human malaria vector Anopheles gambiae, by selectively destroying the X-chromosome during spermatogenesis, through the activity of a naturally-occurring endonuclease that targets a repetitive rDNA sequence highly-conserved in a wide range of organisms. Here we describe a CRISPR-Cas9 sex distortion system that targets ribosomal sequences restricted to the member species of the Anopheles gambiae complex. Expression of Cas9 during spermatogenesis resulted in RNA-guided shredding of the X-chromosome during male meiosis and produced extreme male bias among progeny in the absence of any significant reduction in fertility. The flexibility of CRISPR-Cas9 combined with the availability of genomic data for a range of insects renders this strategy broadly applicable for the species-specific control of any pest or vector species with an XY sex-determination system by targeting sequences exclusive to the female sex chromosome. PMID:27484623

How the oxygen isotope ratio of rain water influences the isotope ratio of chicken eggshell carbonate

NASA Astrophysics Data System (ADS)

Price, Gregory; Grimes, Stephen

2015-04-01

The stable oxygen isotope ratio of chicken eggshell carbonate was analysed from chicken eggs laid under free range, and organic farming regimes from across the UK. The eggshell carbonate oxygen isotope data shows a clear depletion in delta18O distribution from the southwest to the northeast. Although consistently offset by around 1 permil, the same isotopic distribution as that seen in eggshell carbonate is observed in the delta18O ratio of rainfall and groundwater from across the UK. This distribution is related to the Rayleigh distillation of rainfall driven by westerly winds across the UK landmass. The clear relationship observed between eggshell delta18O values and that of rainwater presumably reflects the nature of free range chickens which must be drinking locally derived rainwater and supplementing their diet and water intake with locally derived food. These results suggest that the oxygen isotope value of chicken eggshells can be used as a forensic tool to identify the locality that free range and organic eggs were laid within the UK. Furthermore, if suitable material is preserved in the archaeological and geological record then such a relationship can potentially be used to establish the oxygen isotope value of rainwater from which ancient and / or ancestral birds lived.

A reevaluation of spectral ratios for lunar mare TiO2 mapping

NASA Technical Reports Server (NTRS)

Johnson, Jeffrey R.; Larson, Stephen M.; Singer, Robert B.

1991-01-01

The empirical relation established by Charette et al. (1974) between the 400/560-nm spectral ratio of mature mare soils and weight percent TiO2 has been used extensively to map titanium content in the lunar maria. Relative reflectance spectra of mare regions show that a reference wavelength further into the near-IR, e.g., above 700 nm, could be used in place of the 560-nm band to provide greater contrast (a greater range of ratio values) and hence a more sensitive indicator of titanium content. An analysis of 400/730-nm ratio values derived from both laboratory and telescopic relative reflectance spectra suggests that this ratio provides greater sensitivity to TiO2 content than the 400/560-nm ratio. The increased range of ratio values is manifested in higher contrast 400/730-nm ratio images compared to 400/560-nm ratio images. This potential improvement in sensivity encourages a reevaluation of the original Charette et al. (1974) relation using the 400/730-nm ratio.

The case for cases B and C: intrinsic hydrogen line ratios of the broad-line region of active galactic nuclei, reddenings, and accretion disc sizes

NASA Astrophysics Data System (ADS)

Gaskell, C. Martin

2017-05-01

Low-redshift active galactic nuclei (AGNs) with extremely blue optical spectral indices are shown to have a mean, velocity-averaged, broad-line Hα/Hβ ratio of ≈2.72 ± 0.04, consistent with a Baker-Menzel Case B value. Comparison of a wide range of properties of the very bluest AGNs with those of a luminosity-matched subset of the Dong et al. blue AGN sample indicates that the only difference is the internal reddening. Ultraviolet fluxes are brighter for the bluest AGNs by an amount consistent with the flat AGN reddening curve of Gaskell et al. The lack of a significant difference in the GALEX (far-ultraviolet-near-ultraviolet) colour index strongly rules out a steep Small Magellanic Cloud-like reddening curve and also argues against an intrinsically harder spectrum for the bluest AGNs. For very blue AGNs, the Ly α/Hβ ratio is also consistent with being the Case B value. The Case B ratios provide strong support for the self-shielded broad-line model of Gaskell, Klimek & Nazarova. It is proposed that the greatly enhanced Ly α/Hβ ratio at very high velocities is a consequence of continuum fluorescence in the Lyman lines (Case C). Reddenings of AGNs mean that the far-UV luminosity is often underestimated by up to an order of magnitude. This is a major factor causing the discrepancies between measured accretion disc sizes and the predictions of simple accretion disc theory. Dust covering fractions for most AGNs are lower than has been estimated. The total mass in lower mass supermassive black holes must be greater than hitherto estimated.

Potential for waist-to-height ratio to detect overfat adolescents from a Pacific Island, even those within the normal BMI range.

PubMed

Frayon, Stéphane; Cavaloc, Yolande; Wattelez, Guillaume; Cherrier, Sophie; Lerrant, Yannick; Ashwell, Margaret; Galy, Olivier

2017-12-15

Waist-to-height ratio (WHtR) is a simple anthropometric proxy for central body fat; it is easy to use from a health education perspective. A WHtR value >0.5 has been proposed as a first level indicator of health risk. The first aim of this study was to compare WHtR with values based on body mass index (BMI) in their prediction of the percentage of body fat (%BF) in a multi-ethnic population of adolescents from New-Caledonia (age 11-16year). Secondly, to see whether WHtR >0.5 could be used to detect overfat subjects whose BMI was in the normal range. Body fat percentage (%BF, based on skinfold measurements), BMI and WHtR were calculated for New Caledonian adolescents from different ethnic backgrounds. The relationship between %BF, BMI and WHtR was determined using quadratic models and from linear regression equations. The sensitivity and specificity of WHtR for detecting overfat adolescents (%BF >25% in boys and >30% in girls) were assessed and compared with those from the BMI-based classification. WHtR showed better correlation with %BF than BMI-based measurements. WHtR >0.5 was also more accurate than BMI in detecting overfat adolescents. Moreover, using this boundary value, 8% of adolescents in the normal BMI range were shown to be over-fat. WHtR is a good anthropometric proxy to detect overfat adolescents. Detecting overfat adolescents within the normal BMI range is particularly important for preventing non communicable diseases. We therefore recommend using WHtR for health education programs in the Pacific area and more generally. Copyright © 2017 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

G6PD/PK ratio: a reliable parameter to identify glucose-6-phosphate dehydrogenase deficiency associated with microcytic anemia in heterozygous subjects.

PubMed

Tagarelli, Antonio; Piro, Anna; Tagarelli, Giuseppe; Bastone, Loredana; Paleari, Renata; Mosca, Andrea

2004-10-01

To determine if measuring the ratio of glucose-6-phosphate dehydrogenase (G6PD) to pyruvate kinase (PK) is more reliable than only measuring G6PD activity to identify heterozygous G6PD- individuals with associated microcytic anemia in the Calabrian population, which shows high frequencies of both the thalassaemia (thal) trait and G6PD deficiency. Measurement of G6PD and PK activities was carried out on 205 samples of whole blood from Calabrian subjects of both sexes (age range 10-50 years) using a double starter differential pH-metry technique. The G6PD/PK ratio is able to differentiate G6PD- heterozygous individuals from the normal population. G6PD/PK values also allowed us to easily identify the G6PD- heterozygous subjects with microcytic anaemia. Student's t test shows that G6PD/PK ratio is more reliable in both sample groups, relative to G6PD activity in normal subjects. G6PD/PK ratio is a reliable diagnostic parameter for mass screening for G6PD deficiency.

Composite laminates with negative through-the-thickness Poisson's ratios

NASA Technical Reports Server (NTRS)

Herakovich, C. T.

1984-01-01

A simple analysis using two dimensional lamination theory combined with the appropriate three dimensional anisotropic constitutive equation is presented to show some rather surprising results for the range of values of the through-the-thickness effective Poisson's ratio nu sub xz for angle ply laminates. Results for graphite-epoxy show that the through-the-thickness effective Poisson's ratio can range from a high of 0.49 for a 90 laminate to a low of -0.21 for a + or - 25s laminate. It is shown that negative values of nu sub xz are also possible for other laminates.

Composite laminates with negative through-the-thickness Poisson's ratios

NASA Technical Reports Server (NTRS)

Herakovich, C. T.

1984-01-01

A simple analysis using two-dimensional lamination theory combined with the appropriate three-dimensional anisotropic constitutive equation is presented to show some rather surprising results for the range of values of the through-the-thickness effective Poisson's ratio nu sub xz for angle ply laminates. Results for graphite-epoxy show that the through-the-thickness effective Poisson's ratio can range from a high of 0.49 for a 90 laminate to a low of -0.21 for a + or - 25s laminate. It is shown that negative values of nu sub xz are also possible for other laminates.

Focal ratio degradation in lightly fused hexabundles

NASA Astrophysics Data System (ADS)

Bryant, J. J.; Bland-Hawthorn, J.; Fogarty, L. M. R.; Lawrence, J. S.; Croom, S. M.

2014-02-01

We are now moving into an era where multi-object wide-field surveys, which traditionally use single fibres to observe many targets simultaneously, can exploit compact integral field units (IFUs) in place of single fibres. Current multi-object integral field instruments such as Sydney-AAO Multi-object Integral field spectrograph have driven the development of new imaging fibre bundles (hexabundles) for multi-object spectrographs. We have characterized the performance of hexabundles with different cladding thicknesses and compared them to that of the same type of bare fibre, across the range of fill fractions and input f-ratios likely in an IFU instrument. Hexabundles with 7-cores and 61-cores were tested for focal ratio degradation (FRD), throughput and cross-talk when fed with inputs from F/3.4 to >F/8. The five 7-core bundles have cladding thickness ranging from 1 to 8 μm, and the 61-core bundles have 5 μm cladding. As expected, the FRD improves as the input focal ratio decreases. We find that the FRD and throughput of the cores in the hexabundles match the performance of single fibres of the same material at low input f-ratios. The performance results presented can be used to set a limit on the f-ratio of a system based on the maximum loss allowable for a planned instrument. Our results confirm that hexabundles are a successful alternative for fibre imaging devices for multi-object spectroscopy on wide-field telescopes and have prompted further development of hexabundle designs with hexagonal packing and square cores.

High variable mixture ratio oxygen/hydrogen engine

NASA Technical Reports Server (NTRS)

Erickson, C. M.; Tu, W. H.; Weiss, A. H.

1988-01-01

The ability of an O2/H2 engine to operate over a range of high-propellant mixture ratios was previously shown to be advantageous in single stage to orbit (SSTO) vehicles. The results are presented for the analysis of high-performance engine power cycles operating over propellant mixture ratio ranges of 12 to 6 and 9 to 6. A requirement to throttle up to 60 percent of nominal thrust was superimposed as a typical throttle range to limit vehicle acceleration as propellant is expended. The object of the analysis was to determine areas of concern relative to component and engine operability or potential hazards resulting from the operating requirements and ranges of conditions that derive from the overall engine requirements. The SSTO mission necessitates a high-performance, lightweight engine. Therefore, staged combustion power cycles employing either dual fuel-rich preburners or dual mixed (fuel-rich and oxygen-rich) preburners were examined. Engine mass flow and power balances were made and major component operating ranges were defined. Component size and arrangement were determined through engine layouts for one of the configurations evaluated. Each component is being examined to determine if there are areas of concern with respect to component efficiency, operability, reliability, or hazard. The effects of reducing the maximum chamber pressure were investigated for one of the cycles.

The visual perception of distance ratios outdoors.

PubMed

Norman, J Farley; Adkins, Olivia C; Dowell, Catherine J; Shain, Lindsey M; Hoyng, Stevie C; Kinnard, Jonathan D

2017-05-01

We conducted an experiment to evaluate the ability of 32 younger and older adults to visually perceive distances in an outdoor setting. On any given trial, the observers viewed 2 environmental distances and were required to estimate the distance ratio-the length of the (usually) larger distance relative to that of the shorter. The stimulus distance ratios ranged from 1.0 (the stimulus distances were identical) to 8.0 (1 distance interval was 8.0 times longer than the other). The stimulus distances were presented within a 26 m × 60 m portion of a grassy field. The observers were able to reliably estimate the stimulus distance ratios: The overall Pearson r correlation coefficient relating the judged and actual distance ratios was 0.762. Fifty-eight percent of the variance in the observers' perceived distance ratios could thus be accounted for by variations in the actual stimulus ratios. About half of the observers significantly underestimated the distance ratios, while the judgments of the remainder were essentially accurate. Significant modulatory effects of sex and age occurred, such that the male observers' judgments were the most precise, while those of the older males were the most accurate.

CMOS Active Pixel Sensors as energy-range detectors for proton Computed Tomography.

PubMed

Esposito, M; Anaxagoras, T; Evans, P M; Green, S; Manolopoulos, S; Nieto-Camero, J; Parker, D J; Poludniowski, G; Price, T; Waltham, C; Allinson, N M

2015-06-03

Since the first proof of concept in the early 70s, a number of technologies has been proposed to perform proton CT (pCT), as a means of mapping tissue stopping power for accurate treatment planning in proton therapy. Previous prototypes of energy-range detectors for pCT have been mainly based on the use of scintillator-based calorimeters, to measure proton residual energy after passing through the patient. However, such an approach is limited by the need for only a single proton passing through the energy-range detector in a read-out cycle. A novel approach to this problem could be the use of pixelated detectors, where the independent read-out of each pixel allows to measure simultaneously the residual energy of a number of protons in the same read-out cycle, facilitating a faster and more efficient pCT scan. This paper investigates the suitability of CMOS Active Pixel Sensors (APSs) to track individual protons as they go through a number of CMOS layers, forming an energy-range telescope. Measurements performed at the iThemba Laboratories will be presented and analysed in terms of correlation, to confirm capability of proton tracking for CMOS APSs.

The ZH ratio Analysis of Global Seismic Data

NASA Astrophysics Data System (ADS)

Yano, T.; Shikato, S.; Rivera, L.; Tanimoto, T.

2007-12-01

The ZH ratio, the ratio of vertical to horizontal component of the fundamental Rayleigh wave as a function of frequency, is an alternative approach to phase/group velocity analysis for constructing the S-wave velocity structure. In this study, teleseismic Rayleigh wave data for the frequency range between 0.004Hz to 0.04Hz is used to investigate the interior structure. We have analyzed most of the GEOSCOPE network data and some IRIS GSN stations using a technique developed by Tanimoto and Rivera (2007). Stable estimates of the ZH ratios were obtained for the frequency range for most stations. We have performed the inversion of the measured ZH ratios for the structure in the crust and mantle by using nonlinear iterative scheme. The depth sensitivity kernels for inversion are numerically calculated. Depth sensitivity of the lowest frequency extends to depths beyond 500 km but the sensitivity of the overall data for the frequency band extends down to about 300km. We found that an appropriate selection of an initial model, particularly the depth of Mohorovicic discontinuity, is important for this inversion. The inversion result depends on the initial model and turned out to be non-unique. We have constructed the initial model from the CRUST 2.0. Inversion with equal weighting to each data point tends to reduce variance of certain frequency range only. Therefore, we have developed a scheme to increase weighting to data points that do not fit well after the fifth iteration. This occurs more often for low frequency range, 0.004-0.007Hz. After fitting the lower frequency region, the low velocity zone around a depth of 100km is observed under some stations such as KIP (Kipapa, Hawaii) and ATD (Arta Cave, Djibouti). We have also carried out an analysis on the resolving power of data by examining the eigenvalues-eigenvectors of the least-squares problem. Unfortunately, the normal matrix usually has 1-2 very large eigenvalues, followed by much smaller eigenvalues. The third

Active laser ranging with frequency transfer using frequency comb

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Hongyuan; Wei, Haoyun; Yang, Honglei

2016-05-02

A comb-based active laser ranging scheme is proposed for enhanced distance resolution and a common time standard for the entire system. Three frequency combs with different repetition rates are used as light sources at the two ends where the distance is measured. Pulse positions are determined through asynchronous optical sampling and type II second harmonic generation. Results show that the system achieves a maximum residual of 379.6 nm and a standard deviation of 92.9 nm with 2000 averages over 23.6 m. Moreover, as for the frequency transfer, an atom clock and an adjustable signal generator, synchronized to the atom clock, are used asmore » time standards for the two ends to appraise the frequency deviation introduced by the proposed system. The system achieves a residual fractional deviation of 1.3 × 10{sup −16} for 1 s, allowing precise frequency transfer between the two clocks at the two ends.« less

Nitrogen removal from wastewater and bacterial diversity in activated sludge at different COD/N ratios and dissolved oxygen concentrations.

PubMed

Zielińska, Magdalena; Bernat, Katarzyna; Cydzik-Kwiatkowska, Agnieszka; Sobolewska, Joanna; Wojnowska-Baryła, Irena

2012-01-01

The impact of the organic carbon to nitrogen ratio (chemical oxygen demand (COD)/N) in wastewater and dissolved oxygen (DO) concentration on carbon and nitrogen removal efficiency, and total bacteria and ammonia-oxidizing bacteria (AOB) communities in activated sludge in constantly aerated sequencing batch reactors (SBRs) was determined. At DO of 0.5 and 1.5 mg O2/L during the aeration phase, the efficiency of ammonia oxidation exceeded 90%, with nitrates as the main product. Nitrification and denitrification achieved under the same operating conditions suggested the simultaneous course of these processes. The most effective nitrogen elimination (above 50%) was obtained at the COD/N ratio of 6.8 and DO of 0.5 mg O2/L. Total bacterial diversity was similar in all experimental series, however, for both COD/N ratios of 6.8 and 0.7, higher values were observed at DO of 0.5 mg O2/L. The diversity and abundance of AOB were higher in the reactors with the COD/N ratio of 0.7 in comparison with the reactors with the COD/N of 6.8. For both COD/N ratios applied, the AOB population was not affected by oxygen concentration. Amplicons with sequences indicating membership of the genus Nitrosospira were the determinants of variable technological conditions.

Short-range density functional correlation within the restricted active space CI method

NASA Astrophysics Data System (ADS)

Casanova, David

2018-03-01

In the present work, I introduce a hybrid wave function-density functional theory electronic structure method based on the range separation of the electron-electron Coulomb operator in order to recover dynamic electron correlations missed in the restricted active space configuration interaction (RASCI) methodology. The working equations and the computational algorithm for the implementation of the new approach, i.e., RAS-srDFT, are presented, and the method is tested in the calculation of excitation energies of organic molecules. The good performance of the RASCI wave function in combination with different short-range exchange-correlation functionals in the computation of relative energies represents a quantitative improvement with respect to the RASCI results and paves the path for the development of RAS-srDFT as a promising scheme in the computation of the ground and excited states where nondynamic and dynamic electron correlations are important.

Global earthquake catalogs and long-range correlation of seismic activity (Invited)

NASA Astrophysics Data System (ADS)

Ogata, Y.

2009-12-01

In view of the long-term seismic activity in the world, homogeneity of a global catalog is indispensable. Lately, Engdahl and Villaseñor (2002) compiled a global earthquake catalog of magnitude (M)7.0 or larger during the last century (1900-1999). This catalog is based on the various existing catalogs such as Abe catalog (Abe, 1981, 1984; Abe and Noguchi, 1983a, b) for the world seismicity (1894-1980), its modified catalogs by Perez and Scholz (1984) and by Pacheco and Sykes (1992), and also the Harvard University catalog since 1975. However, the original surface wave magnitudes of Abe catalog were systematically changed by Perez and Scholz (1984) and Pacheco and Sykes (1992). They suspected inhomogeneity of the Abe catalog and claimed that the two seeming changes in the occurrence rate around 1922 and 1948 resulted from magnitude shifts for some instrumental-related reasons. They used a statistical test assuming that such a series of large earthquakes in the world should behave as the stationary Poisson process (uniform occurrences). It is obvious that their claim strongly depends on their a priori assumption of an independent or short-range dependence of earthquake occurrence. We question this assumption from the viewpoint of long-range dependence of seismicity. We make some statistical analyses of the spectrum, dispersion-time diagrams and R/S for estimating and testing of the long-range correlations. We also attempt to show the possibility that the apparent rate change in the global seismicity can be simulated by a certain long-range correlated process. Further, if we divide the globe into the two regions of high and low latitudes, for example, we have different shapes of the cumulative curves to each other, and the above mentioned apparent change-points disappear from the both regions. This suggests that the Abe catalog shows the genuine seismic activity rather than the artifact of the suspected magnitude shifts that should appear in any wide enough regions

xs231Pa/xs230Th ratios in Northeastern Arabian Sea Sediments: Tracing Changes in Thermohaline Circulation over the past 50 ka?}

NASA Astrophysics Data System (ADS)

Pourmand, A.; Marcantonio, F.

2004-12-01

Patterns of millennial changes in productivity and eolian fluxes in the northeastern Arabian Sea are related to stadial-interstadial temperature variations observed in the Greenland ice cores. In an effort to constrain further the relationship between climate at low and high latitudes, we present new xs231Pa/xs230Th results from northeastern Arabian Sea sediments (core 93KL) spanning the past 50 ka. The unique difference in residence time between oceanic 231Pa and 230Th has allowed the xs231Pa/xs230Th activity ratio in sediments from ocean basins to be used as a proxy for various paleoclimatic indicators such as particle flux, particle composition, and thermohaline circulation. Over the past 50 ka, initial xs231Pa/xs230Th activity ratios in sediment from core 93KL are maintained at values significantly higher than the water-column production ratio of 0.093, ranging from 0.138 ( ˜16 ka) to 0.206 ( ˜4.3 ka). Average xs231Pa/xs230Th activity ratios are lower during the last glacial period than during the Holocene. In addition, there are sub-Milankovitch variations superimposed on the pattern of glacial-interglacial variability that are consistent with the timing of North Atlantic climate events. The most prominent feature of the pattern is that the lowest xs231Pa/xs230Th activity ratios coincide with the timing of Heinrich events 1 through 5. In contrast, the highest ratios are usually associated with interstadials. Increased productivity and boundary scavenging seem to exert some control on the variability we observe in the xs231Pa/xs230Th activity ratios. However, changing patterns of ocean thermohaline circulation (THC) also seem to influence these ratios. Specifically, low xs231Pa/xs230Th activity ratios during the Heinrich events may be caused by a slowdown in THC, which leads to a lower supply of Pa to our site in the northeastern Arabian Sea.

A Ratio Explanation for Evolution.

ERIC Educational Resources Information Center

Riss, Pam Helfers

1993-01-01

Describes hands-on physical anthropology activities for teaching students about evolution. Using evidence found in hominid skulls, students conduct investigations that involve calculating ratios. Eight full-page photographs of skulls from the program Stones and Bones are included. (PR)

Transport coefficients of hard-sphere mixtures. III. Diameter ratio 0. 4 and mass ratio 0. 03 at high fluid density

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erpenbeck, J.J.

1993-07-01

The equation of state and the transport coefficients of shear viscosity, thermal conductivity, thermal diffusion, and mutal diffusion are estimated for a binary, equimolar mixture of hard spheres having a diameter ratio of 0.4 and a mass ratio of 0.03 at volumes in the range 1.7[ital V][sub 0] to 3[ital V][sub 0] ([ital V][sub 0]=1/2 [radical]2 N[ital tsum][sub [ital a]x[ital a

Hydrodynamic characteristics over a range of speeds up to 80 feet per second of a rectangular modified flat plate having an aspect ratio of 0.25 and operating at several depths of submersion

NASA Technical Reports Server (NTRS)

Vaughan, Victor L , Jr; Ramsen, John A

1957-01-01

Results of an investigation of the hydrodynamic characteristics over an extended speed range of a rectangular modified flat plate having an aspect ratio of 0.25 and operating at several depths of submersion are presented. Comparisons between these data and data over a lower speed range on a similar aspect-ratio-0.25 flat plate but having one-half the thickness are presented. These comparisons show no significant differences at the low speeds. At high speeds and high angles of attack, where extensive cavitation was present, the lift coefficients were lower than would have been indicated by the results of the previous investigations and the present investigation at the lower angles of attack. A brief discussion and comparison of ventilation are presented which shows two types of planing bubble formation and the effect of increasing the thickness of the model on the ventilation boundary.

Effects of Blowing Spanwise from the Tips of Low-Aspect Ratio Wings of Varying Taper Ratio, with Application to Improving STOL Capability of Fighter Aircraft.

DTIC Science & Technology

1983-02-01

aspect ratio is relatively small. Brooks (ref. 1) worked with rectangular fins of 0.62 and 1.24 aspect ratio in a water medium and showed very large ...airflow rates. Lloyd (ref. 3) worked with an aspect ratio 2.0 rectangular wing using a very wide range of jet momentum coefficient; his results were in...D-A1i35 688 EFFECTS OF BLOWING SPANWISE FROM THE TIPS OF LOW ASPECT in, RATIO WINGS OF VA .(U) NIELSEN ENGINEERING AND RESEARCH INC MOUNTAIN VIEW CA

Isotopic Ratio, Isotonic Ratio, Isobaric Ratio and Shannon Information Uncertainty

NASA Astrophysics Data System (ADS)

Ma, Chun-Wang; Wei, Hui-Ling

2014-11-01

The isoscaling and the isobaric yield ratio difference (IBD) probes, both of which are constructed by yield ratio of fragment, provide cancelation of parameters. The information entropy theory is introduced to explain the physical meaning of the isoscaling and IBD probes. The similarity between the isoscaling and IBD results is found, i.e., the information uncertainty determined by the IBD method equals to β - α determined by the isoscaling (α (β) is the parameter fitted from the isotopic (isotonic) yield ratio).

Activity Patterns of Eurasian Lynx Are Modulated by Light Regime and Individual Traits over a Wide Latitudinal Range

PubMed Central

Heurich, Marco; Hilger, Anton; Küchenhoff, Helmut; Andrén, Henrik; Bufka, Luděk; Krofel, Miha; Mattisson, Jenny; Odden, John; Persson, Jens; Rauset, Geir R.; Schmidt, Krzysztof; Linnell, John D. C.

2014-01-01

The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49°7′N in central Europe to 70°00′N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day–night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey. PMID:25517902

Influence of oilseed supplement ranging in n-6/n-3 ratio on fatty acid composition and Δ5-, Δ6-desaturase protein expression in steer muscles.

PubMed

Turner, T D; Mitchell, A; Duynisveld, J; Pickova, J; Doran, O; McNiven, M A

2012-12-01

This study investigated effects of roasted or extruded oilseed supplementation ranging in n-6/n-3 ratios from 0.3 to 5.0 on the fatty acid composition and expression of delta-5 desaturase (Δ5d) and Δ6-desaturase (Δ6d) protein in commercial steer cheek (m. masseter) and diaphragm (pars costalis diaphragmatis) muscles. In general, the n-6/n-3 ratio of the diet had a subsequent effect on the muscle n-6/n-3 ratio (P < 0.05), with muscle 18:2n-6 and 18:3n-3 content relating to proportion of dietary soya bean and linseed (P < 0.01). Compared with canola, pure linseed and soya bean diets reduced 14:1c-9 and 16:1c-9 (P < 0.05) but increased 18:1t-11 and c-9,t-11 conjugated linoleic acid (CLA) content (P < 0.01). Oilseed processing had a minor influence but extruded oilseeds increase 18:1t-11 and c-9,t-11 CLA compared with roasted (P < 0.05). Polar lipid 18:3n-3 and n-3 long-chain polyunsaturated fatty acid (LC, ⩾20 carbons PUFA) derivative content increased in relation to dietary linseed supplementation in the diaphragm (P < 0.01), whereas only 18:3n-3 was increased in the cheek (P < 0.01). Protein expression did not differ between diets; however, in each muscle the Δ5d protein expression had a stronger association with the desaturase products rather than the precursors. The relationship between Δ5d protein expression and the muscle LC n-6/n-3 ratio was negative in both muscles (P < 0.05). The relationship between Δ6d protein expression and the LC n-6/n-3 ratio was positive in the cheek (P < 0.001) and negative in the diaphragm (P < 0.05). In conclusion, diet n-6/n-3 ratio affected muscle 18:2n-6 and 18:3n-3 deposition, whereas the Δ5d and Δ6d protein expression had some influence on the polar lipid LC-PUFA profile. Results reaffirm that processed oilseeds can be used to increase the proportion of fatty acids potentially beneficial for human health, by influencing the formation of LC-PUFA and reducing the n-6/n-3 ratio.

Influence of the urine flow rate on some caffeine metabolite ratios used to assess CYP1A2 activity.

PubMed

Sinués, Blanca; Fanlo, Ana; Bernal, María Luisa; Mayayo, Esteban; Soriano, María Antonia; Martínez-Ballarin, Enrique

2002-12-01

Five established metabolite ratios (MRs) to measure P450 CYP1A2 activity--MR1 (17X + 17U)/137X, MR2 (AFMU + 1X + 1U)/17U, MR3 (17X/137X), MR4 (AFMU + 1X + 1U + 17X + 17U)/137X, and MR5 (AFMU + 1X + 1U)/17X--were calculated in urine 4-5 hours after caffeine intake. First, to assess the potential of omeprazole to induce CYP1A2 activity, a caffeine test was performed in 27 subjects on two occasions: before and after 14 days on omeprazole (20 mg/day). Samples of urine were analyzed by high-performance liquid chromatography (HPLC) to quantify caffeine and metabolites used to calculate the different caffeine MRs. MR1, MR3, and MR4 were enhanced after treatment; the percentage of change was inversely associated with that of the urine flow, with r values of -0.48, -0.49, and -0.47, respectively. However, MR2 or MR5 were not modified. To determine the reason for these contradictory results, the authors analyzed data of metabolites, ratios, and their components (numerators and denominators) from 152 subjects (who underwent one caffeine test) and their relationship with the urinary flow. Caffeine concentration in urine was the only compound nondependent on the urine flow. Consistently, ratios containing caffeine (MR1, MR3, and MR4) were highly influenced by the rate of urine excretion, since the flow dependence of their numerators is not canceled out by that of caffeine in their denominators. The dependency of the caffeine excretion on renal factors may explain the opposite results found with the different ratios in the aforementioned prospective study of drug interaction, the absence of closer correlations of the five MRs to each other, the discrepancies about the type of frequency distribution of the different MRs (either normal or multimodal), and the higher sensitivity of MR2 to detect gender differences in CYP1A2 activity found in this study. In summary, the data clearly emphasize the need for a strict control of the liquid intake to avoid high urine flows when MRs

Optimization of NaOH Molarity, LUSI Mud/Alkaline Activator, and Na2SiO3/NaOH Ratio to Produce Lightweight Aggregate-Based Geopolymer

PubMed Central

Abdul Razak, Rafiza; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Hardjito, Djwantoro; Yahya, Zarina

2015-01-01

This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA) using LUSI (Sidoarjo mud) and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA) ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value) of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA) ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM) image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced. PMID:26006238

Ranging Behaviour of Commercial Free-Range Laying Hens

PubMed Central

Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

2016-01-01

Simple Summary Commercial free-range production has become a significant sector of the fresh egg market due to legislation banning conventional cages and consumer preference for products perceived as welfare friendly, as access to outdoor range can lead to welfare benefits such as greater freedom of movement and enhanced behavioural opportunities. This study investigated dispersal patterns, feather condition and activity of laying hens in three distinct zones of the range area; the apron area near shed; enriched zone 10–50 m from shed; and outer range beyond 50 m, in six flocks of laying hens under commercial free-range conditions varying in size between 4000 and 24,000 hens. Each flock was visited for four days to record number of hens in each zone, their behaviour, feather condition and nearest neighbour distances (NND), as well as record temperature and relative humidity during the visit. Temperature and relative humidity varied across the study period in line with seasonal variations and influenced the use of range with fewer hens out of shed as temperature fell or relative humidity rose. On average, 12.5% of the hens were observed on the range and most of these hens were recorded in the apron zone as hen density decreased rapidly with increasing distance from the shed. Larger flocks appeared to have a lower proportion of hens on range. The hens used the range more in the early morning followed by a progressive decrease through to early afternoon. The NND was greatest in the outer range and decreased towards the shed. Feather condition was generally good and hens observed in the outer range had the best overall feather condition. Standing, pecking, walking and foraging were the most commonly recorded behaviours and of these, standing occurred most in the apron whereas walking and foraging behaviours were recorded most in the outer range. This study supported the findings of previous studies that reported few hens in the range and greater use of areas closer

Helium/Carbon dioxide ratios as premonitors of volcanic activity.

PubMed

Thomas, D M; Naughton, J J

1979-06-15

The composition of the gaseous emissions of two fumaroles at the summit of Kilauea Volcano was monitored for môre than 2 years. Magma was released from the summit reservoir on three occasions during this period; prior to or during each event the ratios of helium to carbon dioxide in the fumarole gases decreased substantially from that observed during periods of quiescence.

Does the Q - H index show a stronger relationship than the H:Q ratio in regard to knee pain during daily activities in patients with knee osteoarthritis?

PubMed

Fujita, Remi; Matsui, Yasumoto; Harada, Atsushi; Takemura, Marie; Kondo, Izumi; Nemoto, Tetsuya; Sakai, Tadahiro; Hiraiwa, Hideki; Ota, Susumu

2016-12-01

[Purpose] The purpose of this study was to elucidate the relationship between knee muscle strength and knee pain in activities of daily living, based on consideration of the difference between extension and flexion strength (Q - H) and the hamstring:quadriceps (H:Q) ratio in patients with knee osteoarthritis. [Subjects and Methods] The participants were 78 females with knee osteoarthritis, and a total of 133 knees that had not been treated surgically were the targets of this research. The legs were divided according to dominance. Isometric knee extension and flexion muscle strength and knee pain during activities of daily living were measured. The H:Q ratio (flexion/extension muscle strength) and the difference between extension and flexion strength, (extension muscle strength/weight) minus (flexion muscle strength/weight), that is, Q - H, were calculated. The correlation between these indices and the knee pain score during activities of daily living was investigated. [Results] Greater knee pain during activities of daily living was related to lower knee extension muscle strength and Q - H in both the dominant and nondominant legs. Knee flexion muscle strength and the H:Q ratio were not significantly correlated with knee pain during any activities of daily living. [Conclusion] Knee extension muscle strength and Q - H were found to be significantly correlated with knee pain during activities of daily living, whereas the H:Q ratio was not.

Challenges in miniaturized automotive long-range lidar system design

NASA Astrophysics Data System (ADS)

Fersch, Thomas; Weigel, Robert; Koelpin, Alexander

2017-05-01

This paper discusses the current technical limitations posed on endeavors to miniaturize lidar systems for use in automotive applications and how to possibly extend those limits. The focus is set on long-range scanning direct time of flight LiDAR systems using APD photodetectors. Miniaturization evokes severe problems in ensuring absolute laser safety while maintaining the systems' performance in terms of maximum range, signal-to-noise ratio, detection probability, pixel density, or frame rate. Based on hypothetical but realistic specifications for an exemplary system the complete lidar signal path is calculated. The maximum range of the system is used as a general performance indicator. It is determined with the minimum signal-to-noise ratio required to detect an object. Various system parameters are varied to find their impact on the system's range. The reduction of the laser's pulse width and the right choice for the transimpedance amplifier's amplification have shown to be practicable measures to double the system's range.

Validation of a novel protocol for calculating estimated energy requirements and average daily physical activity ratio for the US population: 2005-2006.

PubMed

Archer, Edward; Hand, Gregory A; Hébert, James R; Lau, Erica Y; Wang, Xuewen; Shook, Robin P; Fayad, Raja; Lavie, Carl J; Blair, Steven N

2013-12-01

To validate the PAR protocol, a novel method for calculating population-level estimated energy requirements (EERs) and average physical activity ratio (APAR), in a nationally representative sample of US adults. Estimates of EER and APAR values were calculated via a factorial equation from a nationally representative sample of 2597 adults aged 20 and 74 years (US National Health and Nutrition Examination Survey; data collected between January 1, 2005, and December 31, 2006). Validation of the PAR protocol-derived EER (EER(PAR)) values was performed via comparison with values from the Institute of Medicine EER equations (EER(IOM)). The correlation between EER(PAR) and EER(IOM) was high (0.98; P<.001). The difference between EER(PAR) and EER(IOM) values ranged from 40 kcal/d (1.2% higher than EER(IOM)) in obese (body mass index [BMI] ≥30) men to 148 kcal/d (5.7% higher) in obese women. The 2005-2006 EERs for the US population were 2940 kcal/d for men and 2275 kcal/d for women and ranged from 3230 kcal/d in obese (BMI ≥30) men to 2026 kcal/d in normal weight (BMI <25) women. There were significant inverse relationships between APAR and both obesity and age. For men and women, the APAR values were 1.53 and 1.52, respectively. Obese men and women had lower APAR values than normal weight individuals (P¼.023 and P¼.015, respectively) [corrected], and younger individuals had higher APAR values than older individuals (P<.001). The PAR protocol is an accurate method for deriving nationally representative estimates of EER and APAR values. These descriptive data provide novel quantitative baseline values for future investigations into associations of physical activity and health. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Forensic utility of the carbon isotope ratio of PVC tape backings

NASA Astrophysics Data System (ADS)

Stern, L. A.; Thompson, A. H.; Mehltretter, A. H.; McLaskey, V.; Parish, A.; Aranda, R.

2008-12-01

Forensic interest in adhesive tapes with PVC-backings (polyvinyl chloride, electrical tapes) derives from their use in construction of improvised explosive devices, drug packaging and in a variety of other illicit activities. Due to the range of physical characteristics and chemical compositions of such tapes, traditional microscopic and chemical analysis of the tape backings and adhesives offer a high degree of discrimination between tapes from different manufacturers and products. To evaluate whether carbon isotope ratios may be able to increase discrimination of electrical tapes, particularly with regards to different tapes of the same product, we assessed the PVC-backings of 87 rolls of black electrical tape for their δ13C values. The adhesive on these tapes was physically removed with hexane, and plasticizers within the PVC tape backings were removed by three-20 minute extractions with chloroform. The δ13C values of the PVC tape backings ranged between -23.8 and -41.5 (‰ V-PDB). The carbon isotopic variation within a product (identical brand and product identification) is significant, based on five products with at least 3 rolls (ranges of 7.4‰ (n=3), 10.0‰ (n=6), 4.2‰ (n=16), 3.8‰ (n=6), and 11.5‰ (n=8), respectively). There was no measurable carbon isotope variation in regards to the following: a) along the length of a roll (4 samples from 1 roll); b) between the center and edge of a strip of tape (1 pair); c) between rolls assumed to be from the same lot of tape (2 pairs); d) between different rolls from the same batch of tape (same product purchased at the same time and place; 5 pairs); and e) between samples of a tape at room temperature, heated to 50° C and 80° C for 1 week. For each sample within the population of 87 tapes, carbon isotopes alone exclude 80 to 100% of the tapes as a potential match, with an average exclusion power of 92.5%, using a window of ± 0.4‰. Carbon isotope variations originate from variations in starting

Doing Mathematics with Bicycle Gear Ratios.

ERIC Educational Resources Information Center

Stump, Sheryl L.

2000-01-01

Describes an activity in which students examine bicycle chain-rings, cogs, and gear ratios as a means of exploring algebraic relationships, data collection, scatter plots, and lines of best fit. (KHR)

Assessing neural activity related to decision-making through flexible odds ratio curves and their derivatives.

PubMed

Roca-Pardiñas, Javier; Cadarso-Suárez, Carmen; Pardo-Vazquez, Jose L; Leboran, Victor; Molenberghs, Geert; Faes, Christel; Acuña, Carlos

2011-06-30

It is well established that neural activity is stochastically modulated over time. Therefore, direct comparisons across experimental conditions and determination of change points or maximum firing rates are not straightforward. This study sought to compare temporal firing probability curves that may vary across groups defined by different experimental conditions. Odds-ratio (OR) curves were used as a measure of comparison, and the main goal was to provide a global test to detect significant differences of such curves through the study of their derivatives. An algorithm is proposed that enables ORs based on generalized additive models, including factor-by-curve-type interactions to be flexibly estimated. Bootstrap methods were used to draw inferences from the derivatives curves, and binning techniques were applied to speed up computation in the estimation and testing processes. A simulation study was conducted to assess the validity of these bootstrap-based tests. This methodology was applied to study premotor ventral cortex neural activity associated with decision-making. The proposed statistical procedures proved very useful in revealing the neural activity correlates of decision-making in a visual discrimination task. Copyright © 2011 John Wiley & Sons, Ltd.

Associations between Physical Activity and Obesity Defined by Waist-To-Height Ratio and Body Mass Index in the Korean Population.

PubMed

Lee, On; Lee, Duck-Chul; Lee, Sukho; Kim, Yeon Soo

2016-01-01

This study investigated the associations between physical activity and the prevalence of obesity determined by waist-to-height ratio (WHtR) and body mass index (BMI). This is the first study to our knowledge on physical activity and obesity using a nationally representative sample of South Korean population from The Korea National Health and Nutrition Examination Survey. We categorized individuals into either non-obese or obese defined by WHtR and BMI. Levels of moderate-to-vigorous physical activity were classified as 'Inactive', 'Active', and 'Very active' groups based on the World Health Organization physical activity guidelines. Multivariable logistic regression was used to examine the associations between physical activity and the prevalence of obesity. Physical activity was significantly associated with a lower prevalence of obesity using both WHtR and BMI. Compared to inactive men, odds ratios (ORs) (95% confidence intervals [CIs]) for obesity by WHtR ≥0.50 were 0.69 (0.53-0.89) in active men and 0.76 (0.63-0.91) in very active men (p for trend = 0.007). The ORs (95% CIs) for obesity by BMI ≥25 kg/m2 were 0.78 (0.59-1.03) in active men and 0.82 (0.67-0.99) in very active men (p for trend = 0.060). The ORs (95% CIs) for obesity by BMI ≥30 kg/m2 were 0.40 (0.15-0.98) in active men and 0.90 (0.52-1.56) in very active men (p for trend = 0.978). Compared to inactive women, the ORs (95% CIs) for obesity by WHtR ≥0.50 were 0.94 (0.75-1.18) in active women and 0.84 (0.71-0.998) in very active women (p for trend = 0.046). However, no significant associations were found between physical activity and obesity by BMI in women. We found more significant associations between physical activity and obesity defined by WHtR than BMI. However, intervention studies are warranted to investigate and compare causal associations between physical activity and different obesity measures in various populations.

THE INTRINSIC EDDINGTON RATIO DISTRIBUTION OF ACTIVE GALACTIC NUCLEI IN STAR-FORMING GALAXIES FROM THE SLOAN DIGITAL SKY SURVEY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Mackenzie L.; Hickox, Ryan C.; Black, Christine S.

An important question in extragalactic astronomy concerns the distribution of black hole accretion rates of active galactic nuclei (AGNs). Based on observations at X-ray wavelengths, the observed Eddington ratio distribution appears as a power law, while optical studies have often yielded a lognormal distribution. There is increasing evidence that these observed discrepancies may be due to contamination by star formation and other selection effects. Using a sample of galaxies from the Sloan Digital Sky Survey Data Release 7, we test whether or not an intrinsic Eddington ratio distribution that takes the form of a Schechter function is consistent with previousmore » work suggesting that young galaxies in optical surveys have an observed lognormal Eddington ratio distribution. We simulate the optical emission line properties of a population of galaxies and AGNs using a broad, instantaneous luminosity distribution described by a Schechter function near the Eddington limit. This simulated AGN population is then compared to observed galaxies via their positions on an emission line excitation diagram and Eddington ratio distributions. We present an improved method for extracting the AGN distribution using BPT diagnostics that allows us to probe over one order of magnitude lower in Eddington ratio, counteracting the effects of dilution by star formation. We conclude that for optically selected AGNs in young galaxies, the intrinsic Eddington ratio distribution is consistent with a possibly universal, broad power law with an exponential cutoff, as this distribution is observed in old, optically selected galaxies and X-rays.« less

[The effect of diet ratio of polyunsaturated fatty acids of omega-3 and omega-6 families on activity of aminotransferases and gamma-glutamyltransferase in rat blood serum].

PubMed

Ketsa, O V; Marchenko, M M

2014-01-01

The effect of diet fat compositions with various ratio of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) on alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT) activities in blood serum of 45 white mongrel rats weighing 90-110 g (9 animals in group) has been investigated. Fat components in the semi-synthetic diet, compiled on the basis of AIN-93 diet, and sources of omega-6 and omega-3 PUFA were presented by sunflower oil, soybean oil and fish oil. It has been shown that four-week inclusion of linoleic acid (LA) and alpha-linolenic acid (alpha-LNA) in a ratio of 7:1 into the diet (soybean oil) as well as use of only omega-6 PUFA (sunflower oil) has lead to an increase in the activity of ALT and GGT in rat blood serum compared to control animals treated with the complex of linolenic, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid through the mixture of sunflower oil and fish oil (9:1) with the ratio of omega-6 and omega-3 PUFA 7:1. Along with this, the AST:ALT ratio (de Ritis ratio) was lower (p < 0.05) as compared with the control group of rat, amounting respectively 0.92 +/- 0.08 and 0.79 +/- 0.12 vs 1.26 +/- 0.10. The use of high doses of omega-3 fatty acids (600 mg EPA and 400 mg DHA per kg of animal weight per day coming through fish oil) did not affect the activity of ALT and GGT, but increased AST serum activity (0.47 +/- 0.04 micromoles/min per mg protein) and the de Ritis ratio (2.53 +/- 0.23). The diet deprived with fat increased enzyme activity of ALT, AST and GGT in rat blood serum.

Urinary coproporphyrin I/(I + III) ratio as a surrogate for MRP2 or other transporter activities involved in methotrexate clearance.

PubMed

Benz-de Bretagne, Isabelle; Zahr, Noël; Le Gouge, Amélie; Hulot, Jean-Sébastien; Houillier, Caroline; Hoang-Xuan, Khe; Gyan, Emmanuel; Lissandre, Séverine; Choquet, Sylvain; Le Guellec, Chantal

2014-08-01

The urinary coproporphyrin I/(I + III) ratio may be a surrogate for MRP2 activity. We conducted a prospective study in patients receiving methotrexate (MTX) to examine the relationship between this ratio and the pharmacokinetics of a MRP2 substrate. Three urine samples were collected from 81 patients for UCP I/(I + III) ratio determination: one before (P1), one at the end of MTX infusion (P2), and one on the day of hospital discharge (P3). Three polymorphisms of ABCC2 were analysed and their relationships with basal UCP I/(I + III) ratio values assessed. All associated drugs were recorded and a drug interaction score (DIS) was assigned. Population pharmacokinetic analysis was conducted to assess whether MTX clearance (MTXCL) was associated with the basal UCP I/(I + III) ratio, its variation during MTX infusion, the DIS or other common covariates. The basal UCP I/(I + III) ratio was not associated with ABCC2 polymorphisms and did not differ according to the DIS. Significant changes in the ratio were observed over time, with an increase between P1 and P2 and a decrease at P3 (P < 0.001). No association was found between basal UCP I/(I + III) ratio and MTXCL. The final model indicates that MTXCL was dependent on the change in the ratio between P1 and P3, DIS and creatinine clearance. The basal UCP I/(I + III) ratio is not predictive of MTXCL. However, it is sensitive to the presence of MTX, so it is plausible that it reflects a function modified in response to the drug. © 2014 The British Pharmacological Society.

Sex ratio dynamics and fluctuating selection on personality.

PubMed

Del Giudice, Marco

2012-03-21

Fluctuating selection has often been proposed as an explanation for the maintenance of genetic variation in personality. Here I argue that the temporal dynamics of the sex ratio can be a powerful source of fluctuating selection on personality traits, and develop this hypothesis with respect to humans. First, I review evidence that sex ratios modulate a wide range of social processes related to mating and parenting. Since most personality traits affect mating and parenting behavior, changes in the sex ratio can be expected to result in variable selection on personality. I then show that the temporal dynamics of the sex ratio are intrinsically characterized by fluctuations at various timescales. Finally, I address a number of evolutionary genetic challenges to the hypothesis. I conclude that the sex ratio hypothesis is a plausible explanation of genetic variation in human personality, and may be fruitfully applied to other species as well. Copyright © 2011 Elsevier Ltd. All rights reserved.

Activity of Nivolumab and Utility of Neutrophil-to-Lymphocyte Ratio as a Predictive Biomarker for Advanced Non-Small-Cell Lung Cancer: A Prospective Observational Study.

PubMed

Fukui, Tomoya; Okuma, Yuriko; Nakahara, Yoshiro; Otani, Sakiko; Igawa, Satoshi; Katagiri, Masato; Mitsufuji, Hisashi; Kubota, Masaru; Hiyoshi, Yasuhiro; Ishihara, Mikiko; Kasajima, Masashi; Sasaki, Jiichiro; Naoki, Katsuhiko

2018-05-05

The immune checkpoint inhibitor nivolumab is entering routine oncologic practice. We investigated the safety and efficacy of nivolumab in the real world and alternative predictive factors for survival in patients with advanced non-small-cell lung cancer (NSCLC). We performed a prospective observational study to evaluate the activity of nivolumab treatment for chemotherapy-refractory NSCLC. Patients were treated with nivolumab once every 2 weeks, and the efficacy was assessed every 8 ± 2 weeks. Fifty-two patients were enrolled after nivolumab approval in Japan. These patients received a median of 4 (range, 1-43) cycles of nivolumab. Overall objective response was observed in 12 patients (23.1%). Median progression-free survival was 2.1 (95% confidence interval, 1.0-3.2) months, and 1-year overall survival rate was 59.9%. A total of 23 immune-related adverse events occurred in 20 patients, as follows: 7 cases of pneumonitis, 6 of oral mucositis, 5 of hypothyroidism, 2 of colitis, 2 of liver dysfunction, and 1 of arthritis. All patients recovered after appropriate management. A pretreatment neutrophil-to-lymphocyte ratio (NLR) of ≥ 5 was significantly associated with poor prognosis compared to NLR < 5 (hazard ratio, 4.52; 95% confidence interval, 1.84-11.14; P = .013), independently. Nivolumab showed promising activity with a manageable safety profile in clinical practice, consistent with effects of previous clinical trials. This drug could affect a specific population of patients with advanced NSCLC, and pretreatment NLR was a candidate for surrogate markers for survival benefit of patients with NSCLC treated with nivolumab. Copyright © 2018 Elsevier Inc. All rights reserved.

The impact of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio among patients with intrahepatic cholangiocarcinoma.

PubMed

Buettner, Stefan; Spolverato, Gaya; Kimbrough, Charles W; Alexandrescu, Sorin; Marques, Hugo P; Lamelas, Jorge; Aldrighetti, Luca; Gamblin, T Clark; Maithel, Shishir K; Pulitano, Carlo; Weiss, Matthew; Bauer, Todd W; Shen, Feng; Poultsides, George A; Marsh, J Wallis; IJzermans, Jan N M; Koerkamp, Bas Groot; Pawlik, Timothy M

2018-06-11

Neutrophil-to-lymphocyte ratio and platelets-to-lymphocyte ratio may be host factors associated with prognosis. We sought to determine whether neutrophil-to-lymphocyte and platelets-to-lymphocyte ratio were associated with overall survival among patients undergoing surgery for intrahepatic cholangiocarcinoma. Patients who underwent resection for intrahepatic cholangiocarcinoma between 1990 and 2015 were identified from 12 major centers. Clinicopathologic factors and overall survival were compared among patients stratified by neutrophil-to-lymphocyte ratio and platelets-to-lymphocyte ratio. Risk factors identified on multivariable analysis were included in a prognostic model and the discrimination was assessed using Harrell's concordance index (C index). A total of 991 patients were identified. Median neutrophil-to-lymphocyte ratio and platelets-to-lymphocyte ratio were 2.7 (interquartile range [IQR]: 2.0-4.0) and 109.6 (IQR: 72.4-158.8), respectively. Preoperative neutrophil-to-lymphocyte ratio was elevated (≥5) in 100 patients (10.0%) and preoperative platelets-to-lymphocyte ratio (≥190) in 94 patients (15.2%). Patients with low and high neutrophil-to-lymphocyte ratio and platelets-to-lymphocyte ratio generally had similar baseline characteristics with regard to tumor characteristics. Overall survival was 37.7 months (95% confidence interval [CI]: 32.7-42.6); 1-, 3-, and 5-year overall survival was 78.8%, 51.6%, and 39.3%, respectively. Patients with an neutrophil-to-lymphocyte ratio <5 had a median survival of 47.1 months (95% CI: 37.9-53.3) compared with a median survival of 21.9 months (95% CI: 4.8-39.1) among patients with an neutrophil-to-lymphocyte ratio ≥5 (P = .001). In contrast, patients who had a platelets-to-lymphocyte ratio <190 vs platelets-to-lymphocyte ratio ≥190 had comparable long-term survival (P > .05). On multivariable analysis, an elevated neutrophil-to-lymphocyte ratio was independently associated with decreased overall survival

Export Time of Earthquake-Derived Landslides in Active Mountain Ranges

NASA Astrophysics Data System (ADS)

Croissant, T.; Lague, D.; Steer, P.; Davy, P.

2016-12-01

In active mountain ranges, large earthquakes (Mw > 5-6) trigger numerous landslides that impact river dynamics. These landslides bring local and sudden sediment deposits which are eroded and transported along the river network, causing downstream changes in river geometry, transport capacity and erosion efficiency. The progressive removal of landslide materials has implications for downstream hazards management and for landscape dynamics at the timescale of the seismic cycle. Although the export time of suspended sediments from landslides triggered by large-magnitude earthquakes has been extensively studied, the processes and time scales associated to bedload transport remains poorly studied. Here, we study the sediment export of large landslides with the 2D morphodynamic model, Eros. This model combines: (i) an hydrodynamic model, (ii) a sediment transport and deposition model and (iii) a lateral erosion model. Eros is particularly well suited for this issue as it accounts for the complex retro-actions between sediment transport and fluvial geometry for rivers submitted to external forcings such as abrupt sediment supply increase. Using a simplified synthetic topography we systematically study the influence of pulse volume (Vs) and channel transport capacity (QT) on the export time of landslides. The range of simulated river behavior includes landslide vertical incision, its subsequent removal by lateral erosion and the river morphology modifications induced by downstream sediment propagation. The morphodynamic adaptation of the river increases its transport capacity along the channel and tends to accelerate the landslide evacuation. Our results highlight two regimes: (i) the export time is linearly related to Vs/QT when the sediment pulse introduced in the river does not affect significantly the river hydrodynamic (low Vs/QT) and (ii) the export time is a non-linear function of Vs/QT when the pulse undergoes significant morphodynamic modifications during its

Ankle Ranges of Motion During Extended Activity Periods While Taped and Braced

PubMed Central

Paris, David L.; Kokkaliaris, Jimmy; Vardaxis, Vassilios

1995-01-01

Tape has traditionally been used to support the ankle during activity. More recently, commercial ankle braces have been worn as an alternative. The cumulative information on the effects of taped versus braced ankle support or interbrace comparisons is inconclusive. With few exceptions, ankle brace studies have collected data soon after support conditions were administered. Plantar-dorsiflexion and inversion-eversion ranges of motion (ROM) of 30 subjects were compared under conditions of unsupported, nonelastic adhesivetaped, and Swede-O and Sub Talar Support-braced ankles. We recorded measurements before activity and after periods of 15, 30, 45, and 60 minutes of selected activity on a motorized treadmill. All support conditions significantly reduced preactivity ROM in all directions compared to unsupported ankles. Results showed that the ankle significantly increased in plantarflexion ROM 15 minutes after the initiation of activity with tape or the SubTalar Support-brace, and after 30 minutes with the Swede-O brace. Tape showed further significant increases in plantarflexion ROM after 15-minute intervals of 30, 45, and 60 minutes of activity. All three support conditions had increased significantly in inversion ROM by 15 minutes of activity. The SubTalar Support brace showed a further significant inversion ROM increase between 15 and 30 minutes postactivity. We conclude that the Swede-O and SubTalar Support braces and tape offer significant preactivity ankle support in all four directions of movement. We also conclude that both braces offer longer postactivity support than tape. In inversion ROM and plantarflexion ROM, actions prevalent in ankle sprains, the Swede-O brace retained support longer than the SubTalar Support brace. ImagesFig 1.Fig 2.Fig 3. PMID:16558340

Temperature Measurements in the Solar Transition Region Using N III Line Intensity Ratios

NASA Technical Reports Server (NTRS)

Doron, R.; Doschek, G. A.; Laming, J. M.; Feldman, U.; Bhatia, A. K.

2003-01-01

UV emission from B-like N and O ions a rather rare opportunity for recording spectral lines in a narrow wavelength range that can potentially be used to derive temperatures relevant to the solar transition region. In these ions, the line intensity ratios of the type (2s2p(sup 2) - 2p(sup 3)) / (2s(sup 2)2p - 2s2p(sup 2)) are very sensitive to the electron temperature. Additionally, the lines involving the ratios fall within a range of only - 12 A; in N III the lines fall in the 980 - 992 A range and in O IV in the 780 - 791 A range. In this work, we explore the use of these atomic systems, primarily in N III, for temperature diagnostics of the transition region by analyzing UV spectra obtained by the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer flown on the Solar and Heliospheric Observatory (SOHO). The N III temperature-sensitive line ratios are measured in more than 60 observations. Most of the measured ratios correspond to temperatures in the range 5.7x10(exp 4) - 6.7x10(exp 4) K. This range is considerably lower than the calculated temperature of maximum abundance of N III, which is approx. 7.6x10(exp 4) K. Detailed analysis of the spectra further indicates that the measured ratios are probably somewhat overestimated due to resonant scattering effects in the 2s(sup 2)2p - 2s2p(sup 2) lines and small blends in the 2s2p(sup 2) - 2p3 lines. Actual lower ratios would only increase the disagreement between the ionization balance calculations and present temperature measurements based on a collisional excitation model. In the case of the O IV spectra, we determined that due to the close proximity in wavelength of the weak line (2s2p(sup 2)-2p3 transitions) to a strong Ne VIII line, sufficiently accurate ratio measurements cannot be obtained. Subject headings: atomic data --- atomic processes --- Sun: transition region --- Sun: U V radiation --- techniques: spectroscopic

Study on strontium isotope abundance-ratio measurements by using a 13-MeV proton beam

NASA Astrophysics Data System (ADS)

Jeong, Cheol-Ki; Jang, Han; Lee, Goung-Jin

2016-09-01

The Rb-Sr dating method is used in dating Paleozoic and Precambrian rocks. This method measures the 87Rb and the 87Sr concentrations by using thermal ionization mass spectrometry (TIMS) [J. Hefne et al., Inter. J. Phys. Sci. 3(1), 28 (2008)]. In addition, it calculates the initial 87Sr/86Sr ratio to increase the reliability of Rb-Sr dating. In this study, the 87Sr/86Sr ratio was measured by using a 13-MeV proton accelerator. Proton kinetic energies are in the range of tens of megaelectronvolts, and protons have large absorption cross-sections for ( p, n) reactions with most substances. After absorbing a proton with such a high kinetic energy, an element is converted into a nuclide with its atomic number increased by one via nuclear transmutation. These nuclides usually have short half-lives and return to the original state through radioactive decay. When a strontium sample is irradiated with protons, nuclear transmutation occurs; thus, the strontium isotope present in the sample changes to a yttrium isotope, which is an activated radioisotope. Based on this, the 87Sr/86Sr ratio was calculated by analyzing the gamma-rays emitted by each yttrium isotope. The KIRAMS-13 cyclotron at the Cyclotron Center of Chosun University, where 13-MeV protons can be extracted, was utilized in our experiment. The 87Sr/86Sr isotope ratio was computed for samples irradiated with these protons, and the result was similar to the isotope ratio for the Standard Reference Material, i.e., 98.2 ± 3.4%. As part of the analysis, proton activation analyses were performed using 13-MeV protons, and the experimental results of this research suggest a possible approach for measuring the strontium-isotope abundance ratio of samples.

THE {sup 12}C/{sup 13}C RATIO ON TITAN FROM CASSINI INMS MEASUREMENTS AND IMPLICATIONS FOR THE EVOLUTION OF METHANE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mandt, Kathleen E.; Waite, J. Hunter; Teolis, Benjamin

2012-04-20

We have re-evaluated the Cassini Ion Neutral Mass Spectrometer (INMS) {sup 12}C/{sup 13}C ratios in the upper atmosphere of Titan based on new calibration sensitivities and an improved model for the NH{sub 3} background in the {sup 13}CH{sub 4} mass channel. The INMS measurements extrapolated to the surface give a {sup 12}C/{sup 13}C in CH{sub 4} of 88.5 {+-} 1.4. We compare the results to a revised ratio of 91.1 {+-} 1.4 provided by the Huygens Gas Chromatograph Mass Spectrometer and 86.5 {+-} 7.9 provided by the Cassini Infrared Spectrometer and determine implications of the revised ratios for the evolutionmore » of methane in Titan's atmosphere. Because the measured {sup 12}C/{sup 13}C is within the probable range of primordial values, we can only determine an upper boundary for the length of time since methane began outgassing from the interior, assuming that outgassing of methane (e.g., cryovolcanic activity) has been continuous ever since. We find that three factors play a crucial role in this timescale: (1) the escape rate of methane, (2) the difference between the current and initial ratios and the rate of methane, and (3) production or resupply due to cryovolcanic activity. We estimate an upper limit for the outgassing timescale of 470 Myr. This duration can be extended to 940 Myr if production rates are large enough to counteract the fractionation due to escape and photochemistry. There is no lower limit to the timescale because the current ratios are within the range of possible primordial values.« less

In-situ measurement of dust devil activity at La Jornada Experimental Range, New Mexico, USA

USDA-ARS?s Scientific Manuscript database

We document observations of dust devil vortices using a linear array of 10 miniature pressure- and sunlight-logging stations in summer 2013 at La Jornada Experimental Range in the southwestern USA. These data provide a census of vortex and dust-devil activity at this site. The simultaneous spatial...

Effects of Planetary Gear Ratio on Mean Service Life

NASA Technical Reports Server (NTRS)

Savage, M.; Rubadeux, K. L.; Coe, H. H.

1996-01-01

Planetary gear transmissions are compact, high-power speed reductions which use parallel load paths. The range of possible reduction ratios is bounded from below and above by limits on the relative size of the planet gears. For a single plane transmission, the planet gear has no size at a ratio of two. As the ratio increases, so does the size of the planets relative to the sizes of the sun and ring. Which ratio is best for a planetary reduction can be resolved by studying a series of optimal designs. In this series, each design is obtained by maximizing the service life for a planetary with a fixed size, gear ratio, input speed power and materials. The planetary gear reduction service life is modeled as a function of the two-parameter Weibull distributed service lives of the bearings and gears in the reduction. Planet bearing life strongly influences the optimal reduction lives which point to an optimal planetary reduction ratio in the neighborhood of four to five.

Human variability in mercury toxicokinetics and steady state biomarker ratios.

PubMed

Bartell, S M; Ponce, R A; Sanga, R N; Faustman, E M

2000-10-01

Regulatory guidelines regarding methylmercury exposure depend on dose-response models relating observed mercury concentrations in maternal blood, cord blood, and maternal hair to developmental neurobehavioral endpoints. Generalized estimates of the maternal blood-to-hair, blood-to-intake, or hair-to-intake ratios are necessary for linking exposure to biomarker-based dose-response models. Most assessments have used point estimates for these ratios; however, significant interindividual and interstudy variability has been reported. For example, a maternal ratio of 250 ppm in hair per mg/L in blood is commonly used in models, but a 1990 WHO review reports mean ratios ranging from 140 to 370 ppm per mg/L. To account for interindividual and interstudy variation in applying these ratios to risk and safety assessment, some researchers have proposed representing the ratios with probability distributions and conducting probabilistic assessments. Such assessments would allow regulators to consider the range and like-lihood of mercury exposures in a population, rather than limiting the evaluation to an estimate of the average exposure or a single conservative exposure estimate. However, no consensus exists on the most appropriate distributions for representing these parameters. We discuss published reviews of blood-to-hair and blood-to-intake steady state ratios for mercury and suggest statistical approaches for combining existing datasets to form generalized probability distributions for mercury distribution ratios. Although generalized distributions may not be applicable to all populations, they allow a more informative assessment than point estimates where individual biokinetic information is unavailable. Whereas development and use of these distributions will improve existing exposure and risk models, additional efforts in data generation and model development are required.

Cytoplasm-to-myonucleus ratios and succinate dehydrogenase activities in adult rat slow and fast muscle fibers

NASA Technical Reports Server (NTRS)

Tseng, B. S.; Kasper, C. E.; Edgerton, V. R.

1994-01-01

The relationship between myonuclear number, cellular size, succinate dehydrogenase activity, and myosin type was examined in single fiber segments (n = 54; 9 +/- 3 mm long) mechanically dissected from soleus and plantaris muscles of adult rats. One end of each fiber segment was stained for DNA before quantitative photometric analysis of succinate dehydrogenase activity; the other end was double immunolabeled with fast and slow myosin heavy chain monoclonal antibodies. Mean +/- S.D. cytoplasmic volume/myonucleus ratio was higher in fast and slow plantaris fibers (112 +/- 69 vs. 34 +/- 21 x 10(3) microns3) than fast and slow soleus fibers (40 +/- 20 vs. 30 +/- 14 x 10(3) microns3), respectively. Slow fibers always had small volumes/myonucleus, regardless of fiber diameter, succinate dehydrogenase activity, or muscle of origin. In contrast, smaller diameter (< 70 microns) fast soleus and plantaris fibers with high succinate dehydrogenase activity appeared to have low volumes/myonucleus while larger diameter (> 70 microns) fast fibers with low succinate dehydrogenase activity always had large volume/myonucleus. Slow soleus fibers had significantly greater numbers of myonuclei/mm than did either fast soleus or fast plantaris fibers (116 +/- 51 vs. 55 +/- 22 and 44 +/- 23), respectively. These data suggest that the myonuclear domain is more limited in slow than fast fibers and in the fibers with a high, compared to a low, oxidative metabolic capability.

Effects of unregulated anthropogenic activities on mixing ratios of volatile organic air pollutants--A case study.

PubMed

Majumdar, Dipanjali; Rao, Padma S; Chakraborty, Bipasha Dinda; Srivastava, Anjali

2015-09-01

During the months of October to November, many important festivals are celebrated in India. Celebration of these festivals are marked by extensive use of fireworks or pyrotechnics, bonfire, incense burning, open air community cooking, and temporary eateries using crude fuel such as coal, wood, kerosene, cow dung, burning of raw/semiwood, and coconut shells. The present study deals with the influence of these unregulated anthropogenic activities on ambient mixing level of volatile organic compounds (VOCs), especially some carbonyl compounds. The study was undertaken in the metropolitan city of Kolkata, India, with very high population density, which is even higher during festival period. The average total carbonyl level at different sites in Kolkata varied from 134.8 to 516.5 μg m(-3) in pre-festival season, whereas in post-festival season the same varied from 252.2 to 589.3 μg m(-3). Formaldehyde to acetaldehyde ratio altered from 0.62 in pre-festival season to 1.78 in post-festival season. Diurnal variation also altered, indicating variation in source composition of carbonyls. The total ozone forming potential calculated for all 14 carbonyls in pre-festival season increased by 35% in post-festival season. The effect of anthropogenic activities typical to the event of Diwali night characterized by intense execution of pyrotechnics resulted in significantly high level of carbonyl VOCs. Principal component analysis study for the event of Diwali shows clear contribution of the event on certain carbonyl VOCs. The results indicate elevated primary emissions of these pollutants and also their effect on formation of secondary pollutants. The study emphasizes the need of generating awareness among the communities in society as well as need for regulations to minimize the emissions and related hazards to the extent possible. Altered anthropogenic activities typical of festival season including extensive use of pyrotechnics affect ambient level of volatile organic

Familial influences on the full range of variability in attention and activity levels during adolescence: A longitudinal twin study.

PubMed

Peng, Chun-Zi; Grant, Julia D; Heath, Andrew C; Reiersen, Angela M; Mulligan, Richard C; Anokhin, Andrey P

2016-05-01

To investigate familial influences on the full range of variability in attention and activity across adolescence, we collected maternal ratings of 339 twin pairs at ages 12, 14, and 16, and estimated the transmitted and new familial influences on attention and activity as measured by the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Disorder Symptoms and Normal Behavior Scale. Familial influences were substantial for both traits across adolescence: genetic influences accounted for 54%-73% (attention) and 31%-73% (activity) of the total variance, and shared environmental influences accounted for 0%-22% of the attention variance and 13%-57% of the activity variance. The longitudinal stability of individual differences in attention and activity was largely accounted for by familial influences transmitted from previous ages. Innovations over adolescence were also partially attributable to familial influences. Studying the full range of variability in attention and activity may facilitate our understanding of attention-deficit/hyperactivity disorder's etiology and intervention.

Assessing potential modifications to the activated sludge process to improve simultaneous removal of a diverse range of micropollutants.

PubMed

Petrie, Bruce; McAdam, Ewan J; Lester, John N; Cartmell, Elise

2014-10-01

It is proposed that wastewater treatment facilities meet legislated discharge limits for a range of micropollutants. However, the heterogeneity of these micropollutants in wastewaters make removal difficult to predict since their chemistry is so diverse. In this study, a range of organic and inorganic micropollutants known to be preferentially removed via different mechanisms were selected to challenge the activated sludge process (ASP) and determine its potential to achieve simultaneous micropollutant removal. At a fixed hydraulic retention time (HRT) of 8 h, the influence of an increase in solids retention time (SRT) on removal was evaluated. Maximum achievable micropollutant removal was recorded for all chemicals (estrogens, nonylphenolics and metals) at the highest SRT studied (27 days). Also, optimisation of HRT by extension to 24 h further augmented organic biodegradation. Most notable was the enhancement in removal of the considerably recalcitrant synthetic estrogen 17α-ethinylestradiol which increased to 65 ± 19%. Regression analysis indicates that this enhanced micropollutant behaviour is ostensibly related to the concomitant reduction in food: microorganism ratio. Interestingly, extended HRT also initiated nonylphenol biodegradation which has not been consistently observed previously in real wastewaters. However, extending HRT increased the solubilisation of particulate bound metals, increasing effluent aqueous metals concentrations (i.e., 0.45 μm filtered) by >100%. This is significant as only the aqueous metal phase is to be considered for environmental compliance. Consequently, identification of an optimum process condition for generic micropollutant removal is expected to favour a more integrated approach where upstream process unit optimisation (i.e., primary sedimentation) is demanded to reduce loading of the particle bound metal phase onto the ASP, thereby enabling longer HRT in the ASP to be considered for optimum removal of organic

Imaging energy status in live cells with a fluorescent biosensor of the intracellular ATP-to-ADP ratio

PubMed Central

Tantama, Mathew; Martínez-François, Juan Ramón; Mongeon, Rebecca; Yellen, Gary

2013-01-01

The ATP:ADP ratio is a critical parameter of cellular energy status that regulates many metabolic activities. Here we report an optimized genetically-encoded fluorescent biosensor, PercevalHR, that senses the ATP:ADP ratio. PercevalHR is tuned to the range of intracellular ATP:ADP expected in mammalian cells, and it can be used with one- or two-photon microscopy in live samples. We use PercevalHR to visualize activity-dependent changes in ATP:ADP when neurons are exposed to multiple stimuli, demonstrating that it is a sensitive reporter of physiological changes in energy consumption and production. We also use PercevalHR to visualize intracellular ATP:ADP while simultaneously recording currents from ATP-sensitive potassium (KATP) channels in single cells, showing that PercevalHR enables the study of coordinated variation in ATP:ADP and KATP channel open probability in intact cells. With its ability to monitor changes in cellular energetics within seconds, PercevalHR should be a versatile tool for metabolic research. PMID:24096541

A Short-Range Distance Sensor with Exceptional Linearity

NASA Technical Reports Server (NTRS)

Simmons, Steven; Youngquist, Robert

2013-01-01

A sensor has been demonstrated that can measure distance over a total range of about 300 microns to an accuracy of about 0.1 nm (resolution of about 0.01 nm). This represents an exceptionally large dynamic range of operation - over 1,000,000. The sensor is optical in nature, and requires the attachment of a mirror to the object whose distance is being measured. This work resulted from actively developing a white light interferometric system to be used to measure the depths of defects in the Space Shuttle Orbiter windows. The concept was then applied to measuring distance. The concept later expanded to include spectrometer calibration. In summary, broadband (i.e., white) light is launched into a Michelson interferometer, one mirror of which is fixed and one of which is attached to the object whose distance is to be measured. The light emerging from the interferometer has traveled one of two distances: either the distance to the fixed mirror and back, or the distance to the moving mirror and back. These two light beams mix and produce an interference pattern where some wavelengths interfere constructively and some destructively. Sending this light into a spectrometer allows this interference pattern to be analyzed, yielding the net distance difference between the two paths. The unique feature of this distance sensor is its ability to measure accurately distance over a dynamic range of more than one million, the ratio of its range (about 300 microns) to its accuracy (about 0.1 nanometer). Such a large linear operating range is rare and arises here because both amplitude and phase-matching algorithms contribute to the performance. The sensor is limited by the need to attach a mirror of some kind to the object being tracked, and by the fairly small total range, but the exceptional dynamic range should make it of interest.

The visual perception of distance ratios in physical space.

PubMed

Norman, J Farley; Adkins, Olivia C; Pedersen, Lauren E

2016-06-01

Past studies have consistently demonstrated that human observers cannot accurately perceive environmental distances. Even so, we obviously detect sufficient spatial information to meet the demands of everyday life. In the current experiment, ten younger adults (mean age was 21.8years) and ten older adults (mean age was 72.3years) estimated distance ratios in physical space. On any given trial, observers judged how long one distance interval was relative to another. The 18 stimulus ratios ranged from 1.0 to 9.5; the observers judged each stimulus ratio three times. The average correlation coefficient relating actual distance ratios to perceived ratios was identical (r=0.87) for both younger and older age groups. Despite this strong relationship between perception and reality, the judgments of many individual observers were inaccurate. For example, ten percent of the observers overestimated the stimulus ratios, while fifty percent underestimated the stimulus ratios. Although both under- and overestimation occurred in the current experiment, the results nevertheless demonstrate that human adults can reliably compare environmental distances in different directions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Populations and home range relationships of the box turtle, Terrapene carolina (Linnaeus)

USGS Publications Warehouse

Stickel, L.F.

1949-01-01

A population study of Terrapene carolina (Linnaeus) was made at the Patuxent Research Refuge, Maryland, from 1944 to 1947. A thirty acre area in bottomland forest was selected for intensive study. Turtles were marked by filing notches in marginal scutes according to a code. Turtles make extensive use of brushy shelter during the day as well.as at night. Gully banks and woods openings are used for sunning. Nights are usually spent in a 'form,' constructed by the turtle in leaves, debris, or earth. A form may be used once or it may be used repeatedly by the same or different turtles. Weather conditions most favorable to turtle activity are high humidity, warm sunny days, and frequent rains. Periods of activity are alternated with periods of quiet, even in favorable weather. There is no evidence for territorialism. Ranges of turtles of all ages and both sexes overlap grossly. Turtles are frequently found near each other but no antagonistic behavior has been observed. Adult turtles occupy specific home ranges which they maintain from year to year. Turtles retained their ranges even though a flood that completely covered the study area. Maximum home range diameters were determined by measurements of the mapped ranges of individual turtles. There was no significant difference between sizes of male and female ranges: males 33O+ 26 feet, females 37O+29 feet. A trail-laying device was used in following travel routes for 456 turtle days. Normal movements within the home range are characterized by (1) turns, doublings, detours, and criss-crossing paths, (2) interspersion of fairly direct traverses of the home range, (3) frequently repeated travels over certain routes. Maximum limits of the home range are ordinarily reached within a few days or weeks, although some turtles cover only one portion of the range at a time. Some turtles have two home ranges. One of these turtles was followed with a trailer for 161 days in 1946 and 1947. Trips outside the home range are made by

Emergence of long-range correlations and bursty activity patterns in online communication

NASA Astrophysics Data System (ADS)

Panzarasa, Pietro; Bonaventura, Moreno

2015-12-01

Research has suggested that the activity occurring in a variety of social, economic, and technological systems exhibits long-range fluctuations in time. Pronounced levels of rapidly occurring events are typically observed over short periods of time, followed by long periods of inactivity. Relatively few studies, however, have shed light on the degree to which inhomogeneous temporal processes can be detected at, and emerge from, different levels of analysis. Here we investigate patterns of human activity within an online forum in which communication can be assessed at three intertwined levels: the micro level of the individual users; the meso level of discussion groups and continuous sessions; and the macro level of the whole system. To uncover the relation between different levels, we conduct a number of numerical simulations of a zero-crossing model in which users' behavior is constrained by progressively richer and more realistic rules of social interaction. Results indicate that, when users are solipsistic, their bursty behavior is not sufficient for generating heavy-tailed interevent time distributions at a higher level. However, when users are socially interdependent, the power spectra and interevent time distributions of the simulated and real forums are remarkably similar at all levels of analysis. Social interaction is responsible for the aggregation of multiple bursty activities at the micro level into an emergent bursty activity pattern at a higher level. We discuss the implications of the findings for an emergentist account of burstiness in complex systems.

Impact of 10-Minute Interval Roller Massage on Performance and Active Range of Motion.

PubMed

Hodgson, D D; Quigley, P J; Whitten, J H D; Reid, J C; Behm, David G

2017-11-16

Hodgson, DD, Quigley, PJ, Whitten, JHD, Reid, JC, and Behm, DG. Impact of 10-minute interval roller massage on performance and active range of motion. J Strength Cond Res XX(X): 000-000, 2017-Roller massage (RM) has been shown to increase range of motion (ROM) without subsequent performance deficits. However, prolonged static stretching (SS) can induce performance impairments. The objective of this study was to examine the effects of combining SS and RM with and without subsequent RM on ROM and neuromuscular performance. Subjects (n = 12) participated in 5 sessions: (a) SS only (SS_rest), (b) SS + RM (SS + RM_rest), (c) SS with RM at 10 and 20 minutes after stretch (SS_RM), (d) SS + RM with RM at 10 and 20 minutes after stretch (SS + RM_RM), and (e) control. For the SS conditions, the quadriceps and hamstrings received passive SS for 2 × 30 seconds each. For the SS + RM conditions, SS was applied to the quadriceps and hamstrings for 30 seconds each, and RM was performed for 30 seconds per muscle. SS_RM and SS + RM_RM conditions received an additional 30-second RM at 10 and 20 minutes after warm-up, whereas sessions without additional RM rested for the same duration. Testing measures included hip flexion (HF) and knee flexion (KF) active and passive ROM, hurdle jump height and contact time, countermovement jump height, and maximal voluntary isometric contraction force. Initial KF and HF ROM improvements provided by SS_RM and SS + RM_RM were sustained up to 30 minutes after intervention. Furthermore, SS_RM exhibited greater ROM compared with sessions lacking additional RM in active and passive HF as well as active and passive KF. Similarly, SS + RM_RM elicited greater KF and HF ROM improvements than SS_rest. In conclusion, active KF and HF ROM improvements were prolonged by additional RM, whereas neuromuscular performance remained relatively unaffected.

Effect of multi-walled carbon nanotubes aspect ratio and temperature on the dielectric behavior of alternating alkene-carbon monoxide polyketone nanocomposites

NASA Astrophysics Data System (ADS)

Abu-Surrah, Adnan S.; Abdul Jawad, Saadi; Al-Ramahi, Esraa; Hallak, Awni B.; Khattari, Z.

2015-04-01

New alternating poly(propylene-alt-carbon monoxide/ethylene-alt-carbon monoxide) (PECO)/multiwalled carbon nanotubes (MWCNTs) composites have been prepared. Dielectric permittivity, electric modulus and ac conductivity of the isolated materials were investigated as a function of fiber aspect ratio, frequency and temperature. For aspect ratio of 30 and 200, a transition from insulator to semiconductor was observed at frequency 1×104. However, for high aspect ratio sample (660), no transition was observed and the conductivity is frequency independent in the measured frequency range of 10-106 Hz. The conductivity increases from about 1×10-4 for the sample that contain fibers of aspect ratio 30 and reaches 5×10-2 (Ω m)-1 for aspect ratio was 660. This behavior can be modeled by a circuit that consists of a contact resistance in series with a parallel combination of resistance (R) and capacitance (C). The calculated activation energy for sample filled with fibers having aspect ratio 30 is about 0.26 eV and decreases to about 0.16 eV when the aspect ratio is 660.

The D/H ratio in water from Halley

NASA Technical Reports Server (NTRS)

Eberhardt, P.; Dolder, U.; Schulte, W.; Krankowsky, D.; Laemmerzahl, P.; Hoffman, J. H.; Hodges, R. R.; Berthelier, J. J.; Illiano, J. M.

1986-01-01

The neutral gas mass spectrometer on Giotto made neutral and ion composition measurements with a high mass resolution. Evaluation of the ion data within the contact surface gives a D/H ratio in water from Halley between 0.00006 and 0.00048. While this ratio is definitely not compatible with the D/H in molecular hydrogen of the protosolar nebula or the Jovian and Saturnian atmospheres, it is in the range observed for hydrogen in solar system objects which acquired their hydrogen as part of volatile molecules, e.g., as ices.

Effect of Reinforcer Magnitude on Performance Maintained by Progressive-Ratio Schedules

ERIC Educational Resources Information Center

Rickard, J. F.; Body, S.; Zhang, Z.; Bradshaw, C. M.; Szabadi, E.

2009-01-01

This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive-ratio schedules. Fifteen rats were trained under a progressive-ratio schedule in seven phases of the experiment in which the volume of a 0.6-M sucrose solution reinforcer was varied within the range 6-300 microliters.…

Hormone-mediated adjustment of sex ratio in vertebrates.

PubMed

Navara, Kristen J

2013-12-01

The ability to adjust sex ratios at the individual level exists among all vertebrate groups studied to date. In many cases, there is evidence for facultative adjustment of sex ratios in response to environmental and/or social cues. Because environmental and social information must be first transduced into a physiological signal to influence sex ratios, hormones likely play a role in the adjustment of sex ratio in vertebrates, because the endocrine system acts as a prime communicator that directs physiological activities in response to changing external conditions. This symposium was developed to bring together investigators whose work on adjustment of sex ratio represents a variety of vertebrate groups in an effort to draw comparisons between species in which the sex-determination process is well-established and those in which more work is needed to understand how adjustments in sex ratio are occurring. This review summarizes potential hormone targets that may underlie the mechanisms of adjustment of sex ratio in humans, non-human mammals, birds, reptiles, and fishes.

Radar antenna pointing for optimized signal to noise ratio.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doerry, Armin Walter; Marquette, Brandeis

2013-01-01

The Signal-to-Noise Ratio (SNR) of a radar echo signal will vary across a range swath, due to spherical wavefront spreading, atmospheric attenuation, and antenna beam illumination. The antenna beam illumination will depend on antenna pointing. Calculations of geometry are complicated by the curved earth, and atmospheric refraction. This report investigates optimizing antenna pointing to maximize the minimum SNR across the range swath.

Paralleling power MOSFETs in their active region: Extended range of passively forced current sharing

NASA Technical Reports Server (NTRS)

Niedra, Janis M.

1989-01-01

A simple passive circuit that improves current balance in parallelled power MOSFETs that are not precisely matched and that are operated in their active region from a common gate drive are exhibited. A nonlinear circuit consisting of diodes and resistors generates the differential gate potential required to correct for unbalance while maintaining low losses over a range of current. Also application of a thin tape wound magnetic core to effect dynamic current balance is reviewed, and a simple theory is presented showing that for operation in the active region the branch currents tend to revert to their normal unbalanced values even if the core is not driven into saturation. Results of several comparative experiments are given.

Effect of C/N ratio on extracellular polymeric substances of activated sludge from an anoxic-aerobic sequencing batch reactor treating saline wastewater.

PubMed

Wang, Zichao; Gao, Mengchun; Xin, Yanjun; Ma, Dong; She, Zonglian; Wang, Zhe; Sun, Changqing; Ren, Yun

2014-01-01

The effect of C/N ratio on extracellular polymeric substances (EPS) of activated sludge was investigated in an anoxic-aerobic sequencing batch reactor (SBR) treating saline wastewater. The protein (PN) and protein/polysaccharide (PN/PS) ratio in the loosely bound EPS (LB-EPS) increased with the decrease of C/N ratio, whereas the PS in the LB-EPS decreased. The PS, PN and PN/PS ratio in the tightly bound EPS (TB-EPS) were independent of C/N ratio. Two fluorescence peaks in the LB-EPS and TB-EPS were identified at excitation/emission (Ex/Em) wavelengths of 275-280/335-340 nm and 220-225/330-340 nm by three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, respectively. These peaks in LB-EPS and TB-EPS were, respectively, associated with tryptophan protein-like substances and aromatic protein-like substances. The tryptophan protein-like fluorescence peaks in LB-EPS showed blue shift along the Ex axis and red shift along the Em axis with the decrease of C/N ratio. Fourier transform infrared spectra suggested that the variation of C/N ratio had more distinct effect on the functional groups of protein in the LB-EPS than those in the TB-EPS. The sludge volume index value decreased with the increase of LB-EPS, but there was no correlation between SVI and TB-EPS.

Stable isotope ratio profiling of testosterone preparations.

PubMed

Cawley, Adam; Collins, Michael; Kazlauskas, Rymantas; Handelsman, David J; Heywood, Robert; Longworth, Mitchell; Arenas-Queralt, Andrea

2010-01-01

Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is the preferred method of confirming the administration of exogenous testosterone by athletes. This relies on synthetic testosterone preparations being depleted in (13) C compared to natural testosterone. There is concern, however, about the existence of synthetic testosterone products that are unexpectedly (13) C-enriched and which may allow athletes to circumvent the current GC-C-IRMS test. Further to the reported studies of legitimate pharmaceutical-grade testosterone products, a detailed analysis of seized materials from border-level seizures was required to obtain intelligence concerning trends in 'black market' testosterone manufacture and distribution. The sample set collected for this study between 2006 and 2009 inclusive provided a δ(13) C range (n = 266) of -22.9‰ to -32.6‰ with mean and median values of -28.4‰ and -28.6‰, respectively. Within this distribution there were 24 samples (9%) confirmed to have δ(13) C values in the range reported for endogenous urinary steroid metabolites (≥ -25.8‰). The benefit of δ(13) C profiling for testosterone preparations was demonstrated by the ability to identify specific seized products that can be target tested for future intelligence purposes. In addition, the potential of stable hydrogen isotope ratio ((2) H/(1) H; δ(2) H) discrimination to complement δ(13) C analysis was investigated. Methodologies for the determination of δ(2) H values by gas chromatography-thermal conversion-isotope ratio mass spectrometry (GC-TC-IRMS) were developed to provide a δ(2) H range (n = 173) of -177‰ to -268‰ with mean and median values of -231‰ and -234‰, respectively. Copyright © 2010 John Wiley & Sons, Ltd.

Validation of serum free light chain reference ranges in primary care.

PubMed

Galvani, Luca; Flanagan, Jane; Sargazi, Mansour; Neithercut, William D

2016-05-01

The demand for measurement of serum immunoglobulin free kappa (κ) and lambda (λ) light chains has increased. The κ:λ ratio is used to assist in diagnosis/monitoring of plasma cell disorders. The binding site reference range for serum-free light chain κ:λ ratios of 0.26-1.65 was derived from healthy volunteers. Subsequently, a reference range of 0.37-3.1 for patients with chronic kidney disease has been proposed. Elevated free light chain concentrations and borderline raised free light chain ratios also may be found in polyclonal gammopathies and with other non-renal illnesses. This assessment was conducted to validate the established free light chain reference ranges in individuals from primary care. A total of 130 samples were identified from routine blood samples collected in primary care for routine biochemistry testing and estimated glomerular filtration rate calculation. The median and range of κ:λ ratios found in each estimated glomerular filtration rate group used for chronic kidney disease classification were higher than previously described. This was the case for individuals with normal or essentially normal renal function with estimated glomerular filtration rates>90, (0.58-1.76) and estimated glomerular filtration rate of 60-90 mL/min/1.73 m(2), (0.71-1.93). Individuals with estimated glomerular filtration rate 15-30, (0.72-4.50) and estimated glomerular filtration rate <15 ml/min/1.73 m(2) (0.71-4.95) also had higher values when compared to the current renal reference range of 0.37-3.10. Elevation of free light chain-κ:λ ratios may occur in the absence of a reduced renal function shown by a normal estimated glomerular filtration rate and in the presence of reduced renal function by estimated glomerular filtration rate when comparing results with the established reference ranges. Explanations include choice of analytical systems or the presence of other concurrent non-plasma cell illness. © The Author(s) 2016.

Ratio maps of iron ore deposits Atlantic City district, Wyoming

NASA Technical Reports Server (NTRS)

Vincent, R. K.

1973-01-01

Preliminary results of a spectral rationing technique are shown for a region at the southern end of the Wind River Range, Wyoming. Digital ratio graymaps and analog ratio images have been produced for the test site, but ground truth is not yet available for thorough interpretation of these products. ERTS analog ratio images were found generally better than either ERTS single-channel images or high altitude aerial photos for the discrimination of vegetation from non-vegetation in the test site region. Some linear geological features smaller than the ERTS spatial resolution are seen as well in ERTS ratio and single-channel images as in high altitude aerial photography. Geochemical information appears to be extractable from ERTS data. Good preliminary quantitative agreement between ERTS-derived ratios and laboratory-derived reflectance ratios of rocks and minerals encourage plans to use lab data as training sets for a simple ratio gating logic approach to automatic recognition maps.

Long-range speckle imaging theory, simulation, and brassboard results

NASA Astrophysics Data System (ADS)

Riker, Jim F.; Tyler, Glenn A.; Vaughn, Jeff L.

2017-09-01

In the SPIE 2016 Unconventional Imaging session, the authors laid out a breakthrough new theory for active array imaging that exploits the speckle return to generate a high-resolution picture of the target. Since then, we have pursued that theory even in long-range (<1000-km) engagement scenarios and shown how we can obtain that high-resolution image of the target using only a few illuminators, or by using many illuminators. There is a trade of illuminators versus receivers, but many combinations provide the same synthetic aperture resolution. We will discuss that trade, along with the corresponding radiometric and speckle-imaging Signal-to-Noise Ratios (SNR) for geometries that can fit on relatively small aircraft, such as an Unmanned Aerial Vehicle (UAV). Furthermore, we have simulated the performance of the technique, and we have created a laboratory version of the approach that is able to obtain high-resolution speckle imagery. The principal results presented in this paper are the Signal to Noise Ratios (SNR) for both the radiometric and the speckle imaging portions of the problem, and the simulated results obtained for representative arrays.

Methods of expanding bacteriophage host-range and bacteriophage produced by the methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crown, Kevin K.; Santarpia, Joshua

A method of producing novel bacteriophages with expanded host-range and bacteriophages with expanded host ranges are disclosed. The method produces mutant phage strains which are infectious to a second host and can be more infectious to their natural host than in their natural state. The method includes repeatedly passaging a selected phage strain into bacterial cultures that contain varied ratios of its natural host bacterial strain with a bacterial strain that the phage of interest is unable to infect; the target-host. After each passage the resulting phage are purified and screened for activity against the target-host via double-overlay assays. Whenmore » mutant phages that are shown to infect the target-host are discovered, they are further propagated in culture that contains only the target-host to produce a stock of the resulting mutant phage.« less

An optimally evolved connective ratio of neural networks that maximizes the occurrence of synchronized bursting behavior

PubMed Central

2012-01-01

Background Synchronized bursting activity (SBA) is a remarkable dynamical behavior in both ex vivo and in vivo neural networks. Investigations of the underlying structural characteristics associated with SBA are crucial to understanding the system-level regulatory mechanism of neural network behaviors. Results In this study, artificial pulsed neural networks were established using spike response models to capture fundamental dynamics of large scale ex vivo cortical networks. Network simulations with synaptic parameter perturbations showed the following two findings. (i) In a network with an excitatory ratio (ER) of 80-90%, its connective ratio (CR) was within a range of 10-30% when the occurrence of SBA reached the highest expectation. This result was consistent with the experimental observation in ex vivo neuronal networks, which were reported to possess a matured inhibitory synaptic ratio of 10-20% and a CR of 10-30%. (ii) No SBA occurred when a network does not contain any all-positive-interaction feedback loop (APFL) motif. In a neural network containing APFLs, the number of APFLs presented an optimal range corresponding to the maximal occurrence of SBA, which was very similar to the optimal CR. Conclusions In a neural network, the evolutionarily selected CR (10-30%) optimizes the occurrence of SBA, and APFL serves a pivotal network motif required to maximize the occurrence of SBA. PMID:22462685

Mass spectrometric measurement of urinary kynurenine-to-tryptophan ratio in children with and without urinary tract infection.

PubMed

Yarbrough, Melanie L; Briden, Kelleigh E; Mitsios, John V; Weindel, Annette L; Terrill, Cindy M; Hunstad, David A; Dietzen, Dennis J

2018-04-19

Indoleamine-2,3-dioxygenase (IDO) catalyzes the first step of tryptophan (Trp) catabolism, yielding kynurenine (Kyn) metabolites. The kynurenine-to-tryptophan (K/T) ratio is used as a surrogate for biological IDO enzyme activity. IDO expression is increased during Escherichia coli urinary tract infection (UTI). Thus, our objective was to develop a method for measurement of Kyn/Trp ratio in human blood and urine and evaluate its use as a biomarker of UTI. A mass spectrometric method was developed to measure Trp and Kyn in serum and urine specimens. The method was applied to clinical urine specimens from symptomatic pediatric patients with laboratory-confirmed UTI or other acute conditions and from healthy controls. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was linear to 500 μmol/L for both Trp and Kyn. Imprecision ranged from 5 to 15% for Trp and 6-20% for Kyn. Analytical recoveries of Trp and Kyn ranged from 96 to 119% in serum and 90-97% in urine. No correlation was found between the K/T ratio and circulating IDO mass (r = 0.110) in serum. Urinary Kyn and Trp in the pediatric test cohort demonstrated elevations in the K/T ratio in symptomatic patients with UTI (median 13.08) and without UTI (median 14.38) compared to healthy controls (median 4.93; p < 0.001 for both comparisons). No significant difference in K/T ratio was noted between symptomatic patients with and without UTI (p = 0.84). Measurement of Trp and Kyn by LC-MS/MS is accurate and precise in serum and urine specimens. While urinary K/T ratio is not a specific biomarker for UTI, it may represent a general indicator of a systemic inflammatory process. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

A Novel Unit Cell for Active Switches in the Millimeter-Wave Frequency Range

NASA Astrophysics Data System (ADS)

Müller, Daniel; Scherer, Gunnar; Lewark, Ulrich J.; Massler, Hermann; Wagner, Sandrine; Tessmann, Axel; Leuther, Arnulf; Zwick, Thomas; Kallfass, Ingmar

2018-02-01

This paper presents a novel transistor unit cell which is intended to realize compact active switches in the high millimeter-wave frequency range. The unit cell consists of the combination of shunt and common gate transistor within a four-finger transistor cell, achieving gain in the amplifying state as well as good isolation in the isolating state. Gate width-dependent characteristics of the unit cell as well as the design of actual switch implementations are discussed in detail. To verify the concept, two switches, a single pole double throw (SPDT) switch and single pole quadruple throw (SP4T) switch, intended for the WR3 frequency range (220-325 GHz) were manufactured and characterized. The measured gain at 250 GHz is 4.6 and 2.2 dB for the SPDT and SP4T switch, respectively. An isolation of more than 24 dB for the SPDT switch and 12.8 dB for the SP4T switch was achieved.

RATIO_TOOL - SOFTWARE FOR COMPUTING IMAGE RATIOS

NASA Technical Reports Server (NTRS)

Yates, G. L.

1994-01-01

Geological studies analyze spectral data in order to gain information on surface materials. RATIO_TOOL is an interactive program for viewing and analyzing large multispectral image data sets that have been created by an imaging spectrometer. While the standard approach to classification of multispectral data is to match the spectrum for each input pixel against a library of known mineral spectra, RATIO_TOOL uses ratios of spectral bands in order to spot significant areas of interest within a multispectral image. Each image band can be viewed iteratively, or a selected image band of the data set can be requested and displayed. When the image ratios are computed, the result is displayed as a gray scale image. At this point a histogram option helps in viewing the distribution of values. A thresholding option can then be used to segment the ratio image result into two to four classes. The segmented image is then color coded to indicate threshold classes and displayed alongside the gray scale image. RATIO_TOOL is written in C language for Sun series computers running SunOS 4.0 and later. It requires the XView toolkit and the OpenWindows window manager (version 2.0 or 3.0). The XView toolkit is distributed with Open Windows. A color monitor is also required. The standard distribution medium for RATIO_TOOL is a .25 inch streaming magnetic tape cartridge in UNIX tar format. An electronic copy of the documentation is included on the program media. RATIO_TOOL was developed in 1992 and is a copyrighted work with all copyright vested in NASA. Sun, SunOS, and OpenWindows are trademarks of Sun Microsystems, Inc. UNIX is a registered trademark of AT&T Bell Laboratories.

In-line process control for laser welding of titanium by high dynamic range ratio pyrometry and plasma spectroscopy

NASA Astrophysics Data System (ADS)

Lempe, B.; Taudt, C.; Baselt, T.; Rudek, F.; Maschke, R.; Basan, F.; Hartmann, P.

2014-02-01

The production of complex titanium components for various industries using laser welding processes has received growing attention in recent years. It is important to know whether the result of the cohesive joint meets the quality requirements of standardization and ultimately the customer requirements. Erroneous weld seams can have fatal consequences especially in the field of car manufacturing and medicine technology. To meet these requirements, a real-time process control system has been developed which determines the welding quality through a locally resolved temperature profile. By analyzing the resulting weld plasma received data is used to verify the stability of the laser welding process. The determination of the temperature profile is done by the detection of the emitted electromagnetic radiation from the material in a range of 500 nm to 1100 nm. As detectors, special high dynamic range CMOS cameras are used. As the emissivity of titanium depends on the wavelength, the surface and the angle of radiation, measuring the temperature is a problem. To solve these a special pyrometer setting with two cameras is used. That enables the compensation of these effects by calculating the difference between the respective pixels on simultaneously recorded images. Two spectral regions with the same emissivity are detected. Therefore the degree of emission and surface effects are compensated and canceled out of the calculation. Using the spatially resolved temperature distribution the weld geometry can be determined and the laser process can be controlled. The active readjustment of parameters such as laser power, feed rate and inert gas injection increases the quality of the welding process and decreases the number of defective goods.

Influences of Different Conditioners on Dehydration Ratio of Activated Sludge

NASA Astrophysics Data System (ADS)

Zhuo, Qiongfang; Zheng, Wenli; Yi, Hao; Chen, Sili; Xu, Zhencheng; Jin, Zhong; Lan, Yongzhe; Guo, Qingwei

2017-11-01

Excess sludge contains a large quantity of water with water content reaching about 97%-99%. Besides microorganisms and germs, the sludge is of complicated composition, including heavy metals, persistent organic pollutants, PPCPs, endocrine disrupters, etc. It covers a large area with harmfulness, so it needs further treatment. However, due to existence of extracellular polymeric substances in the sludge, the sludge has poor dehydration property, so how to improve dehydration of sludge is a difficult point in water treatment industry. Chemical conditioning—mechanical dehydration method is sludge dehydration technology which has been widely applied in China. Most sludge treatment plants use organic and inorganic conditioners like polyacrylamide (PAM), polyaluminum chloride (PAC) and polymerized ferrous sulfate (PFS), etc. With characteristics of low toxicity and degradation resistance, these conditioners pose potential risks to the environment and they are adverse to follow-up resource utilization. Therefore, influences of 17 conditioners on sludge dehydration ratio were discussed in this paper, expecting to seek for green, environmentally friendly and highly efficient conditioner so as to improve resource utilization ratio of sludge.

Implications of Fast Reactor Transuranic Conversion Ratio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steven J. Piet; Edward A. Hoffman; Samuel E. Bays

2010-11-01

Theoretically, the transuranic conversion ratio (CR), i.e. the transuranic production divided by transuranic destruction, in a fast reactor can range from near zero to about 1.9, which is the average neutron yield from Pu239 minus 1. In practice, the possible range will be somewhat less. We have studied the implications of transuranic conversion ratio of 0.0 to 1.7 using the fresh and discharge fuel compositions calculated elsewhere. The corresponding fissile breeding ratio ranges from 0.2 to 1.6. The cases below CR=1 (“burners”) do not have blankets; the cases above CR=1 (“breeders”) have breeding blankets. The burnup was allowed to floatmore » while holding the maximum fluence to the cladding constant. We graph the fuel burnup and composition change. As a function of transuranic conversion ratio, we calculate and graph the heat, gamma, and neutron emission of fresh fuel; whether the material is “attractive” for direct weapon use using published criteria; the uranium utilization and rate of consumption of natural uranium; and the long-term radiotoxicity after fuel discharge. For context, other cases and analyses are included, primarily once-through light water reactor (LWR) uranium oxide fuel at 51 MWth-day/kg-iHM burnup (UOX-51). For CR<1, the heat, gamma, and neutron emission increase as material is recycled. The uranium utilization is at or below 1%, just as it is in thermal reactors as both types of reactors require continuing fissile support. For CR>1, heat, gamma, and neutron emission decrease with recycling. The uranium utilization exceeds 1%, especially as all the transuranic elements are recycled. exceeds 1%, especially as all the transuranic elements are recycled. At the system equilibrium, heat and gamma vary by somewhat over an order of magnitude as a function of CR. Isotopes that dominate heat and gamma emission are scattered throughout the actinide chain, so the modest impact of CR is unsurprising. Neutron emitters are preferentially

Highly Active Au/δ-MoC and Cu/δ-MoC Catalysts for the Conversion of CO2: The Metal/C Ratio as a Key Factor Defining Activity, Selectivity, and Stability.

PubMed

Posada-Pérez, Sergio; Ramírez, Pedro J; Evans, Jaime; Viñes, Francesc; Liu, Ping; Illas, Francesc; Rodriguez, José A

2016-07-06

The ever growing increase of CO2 concentration in the atmosphere is one of the main causes of global warming. Thus, CO2 activation and conversion toward valuable added compounds is a major scientific challenge. A new set of Au/δ-MoC and Cu/δ-MoC catalysts exhibits high activity, selectivity, and stability for the reduction of CO2 to CO with some subsequent selective hydrogenation toward methanol. Sophisticated experiments under controlled conditions and calculations based on density functional theory have been used to study the unique behavior of these systems. A detailed comparison of the behavior of Au/β-Mo2C and Au/δ-MoC catalysts provides evidence of the impact of the metal/carbon ratio in the carbide on the performance of the catalysts. The present results show that this ratio governs the chemical behavior of the carbide and the properties of the admetal, up to the point of being able to switch the rate and mechanism of the process for CO2 conversion. A control of the metal/carbon ratio paves the road for an efficient reutilization of this environmental harmful greenhouse gas.

Highly active Au/δ-MoC and Cu/δ-MoC catalysts for the conversion of CO 2: The metal/C ratio as a key factor defining activity, selectivity, and stability

DOE PAGES

Posada-Pérez, Sergio; Ramírez, Pedro J.; Evans, Jaime; ...

2016-06-16

The ever growing increase of CO 2 concentration in the atmosphere is one of the main causes of global warming. Thus, CO 2 activation and conversion toward valuable added compounds is a major scientific challenge. A new set of Au/δ-MoC and Cu/δ-MoC catalysts exhibits high activity, selectivity, and stability for the reduction of CO 2 to CO with some subsequent selective hydrogenation toward methanol. Sophisticated experiments under controlled conditions and calculations based on density functional theory have been used to study the unique behavior of these systems. A detailed comparison of the behavior of Au/β-Mo 2C and Au/δ-MoC catalysts providesmore » evidence of the impact of the metal/carbon ratio in the carbide on the performance of the catalysts. The present results show that this ratio governs the chemical behavior of the carbide and the properties of the admetal, up to the point of being able to switch the rate and mechanism of the process for CO 2 conversion. Here, a control of the metal/carbon ratio paves the road for an efficient reutilization of this environmental harmful greenhouse gas.« less

Investigation of Model Sunscreen Formulations Comparing the Sun Protection Factor, the Universal Sun Protection Factor and the Radical Formation Ratio.

PubMed

Syring, Felicia; Weigmann, Hans-Jürgen; Schanzer, Sabine; Meinke, Martina C; Knorr, Fanny; Lademann, Jürgen

2016-01-01

In view of globally rising skin cancer rates and harmful effects exerted by sunlight throughout the ultraviolet, visible and infrared ranges, an objective, safe and comprehensive method for determining sunscreen efficacy is required in order to warrant safe sun exposure. In this study, the influence of characteristic active ingredients (chemical filters, physical filters and antioxidants) on different sunscreen indicators, including the universal sun protection factor and the radical formation ratio, was determined and compared to their influence on sun protection factor values. Spectroscopic universal sun protection factor measurements were conducted ex vivo by analyzing tape strips taken from human skin, and radical formation ratio determination was performed via electron paramagnetic resonance spectroscopy using porcine ear skin ex vivo. The sun protection factor determination was conducted according to ISO standards (ISO 24444:2010). It was shown that chemical filters provide a protective effect which was measurable by all methods examined (spectroscopy, electron paramagnetic resonance spectroscopy and erythema formation). Physical filters, when used as single active ingredients, increased protective values in universal sun protection factor and sun protection factor measurements but exhibited no significant effect on universal sun protection factor measurements when used in combination with chemical filters or antioxidants. Antioxidants were shown to increase sun protection factor values. Radical formation ratio values were shown to be influenced merely by chemical filters, leading to the conclusion that the universal sun protection factor is the most suitable efficacy indicator for the ultraviolet range. © 2015 S. Karger AG, Basel.

Solar Records: The Wolf Sunspot Index and Umbral/Penumbral Ratio

DOE Data Explorer

Hoyt, Douglas V. [National Center for Atmospheric Research, Boulder, CO (United States)

1985-01-01

These data from observations of sunspot activity cover the period 1875 through 1981; reconstructions are possible back to 1832. Available sunspot models and the theory of mixing length indicate that the observed changes in the umbral/penumbral (U/P) ratio may be equivalent to changes in the solar constant. The U/P ratio is calculated from measurements of solar activity and has been shown to be in good agreement with the Northern Hemisphere temperature record. The data consist of year, number of sunspot groups, Wolf sunspot number, umbra area, whole area, penumbral area, and umbral/penumbral ratio. The data are in one file (3.3 kB).

Warfarin Patients With Anemia Show Trend of Out-of-Range International Normalized Ratio Frequency With Point-of-Care Testing in an Anticoagulation Clinic.

PubMed

DeRemer, Christina E; McMichael, Bliss; Young, Henry N

2018-01-01

Many factors influence international normalized ratio (INR); however, few studies have examined the impact of anemia in warfarin patients. The primary objective of this study was to explore the relationship between in-clinic anemia and the control of INR within an anticoagulation clinic. A retrospective chart review was performed on a random sample of patients seen in an academic medical center pharmacy-managed anticoagulation clinic. Hemochron® Signature Elite machine was utilized to monitor point-of-care (POC) INR. In-clinic anemia was defined as hematocrit <32%. Statistical analyses were conducted using STATA MP a webbased platform ( https://www.stata.com/statamp/ ). Of the 300 patients analyzed, 45 (15%) patients had in-clinic anemia. Patients with in-clinic anemia were more likely to be younger ( P < .05), female ( P < .05), and have a diagnosis of sickle cell disease or anemia ( P < .05). In the unadjusted logistic regression model, patients with in-clinic anemia were less likely to have an in-range INR ( OR: 0.52; 95% CI: 0.27-0.98). The adjusted regression model did not show significance. Study results suggest that in-clinic anemia may be more prevalent among younger, female patients prescribed warfarin, and patients diagnosed with in-clinic anemia may be a risk factor for out-of-range INR. Pharmacists practicing in anticoagulation clinics can incorporate this information into patient care practice in efforts to maintain optimal management.

40 CFR 86.322-79 - NDIR CO2 rejection ratio check.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 19 2012-07-01 2012-07-01 false NDIR CO2 rejection ratio check. 86.322... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission....322-79 NDIR CO2 rejection ratio check. (a) Zero and span the analyzer on the lowest range that will be...

40 CFR 86.322-79 - NDIR CO2 rejection ratio check.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 19 2013-07-01 2013-07-01 false NDIR CO2 rejection ratio check. 86.322... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission....322-79 NDIR CO2 rejection ratio check. (a) Zero and span the analyzer on the lowest range that will be...

40 CFR 86.322-79 - NDIR CO2 rejection ratio check.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 18 2011-07-01 2011-07-01 false NDIR CO2 rejection ratio check. 86.322... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission....322-79 NDIR CO2 rejection ratio check. (a) Zero and span the analyzer on the lowest range that will be...

40 CFR 86.322-79 - NDIR CO2 rejection ratio check.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false NDIR CO2 rejection ratio check. 86.322... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission....322-79 NDIR CO2 rejection ratio check. (a) Zero and span the analyzer on the lowest range that will be...

Home-range and activity pattern of rehabilitated malayan sun bears (Helarctos malayanus) in the Tembat Forest Reserve, Terengganu

NASA Astrophysics Data System (ADS)

Abidin, Mohammad Kamaruddin Zainal; Mohammed, Ahmad Azhar; Nor, Shukor Md

2018-04-01

Re-introduction programme has been adopted in solving the conflict issues related with the Malayan sun bears in Peninsular Malaysia. Two rehabilitated sun bears (#1533 and #1532) were collared and released in Tembat Forest Reserve, Hulu Terengganu to study the home-range and activity pattern. Tracking of sun bear in wild have be conducted manually by using telemetry devices namely radio frequency systems and GPS-UHF download system. A total of 912 locations were recorded. The home range size (indicate by the size of convex polygon) of bear #1533 is larger than bear #1532, with value of 95% minimum convex polygon was 130 km2 compared to its counterpart was 33.28 km2. Bears moved to forest (primary and secondary) and oil palm area. Bear #1533 and #1532 were more active in daytime (diurnal) especially from sunrise to midday. Activity pattern of both rehabilitated bears suggested influence by their daily activity in captivity. This study has proposed two guidelines in re-introduction, 1) minimum distance between release site and possible conflict area is 10-13 km and 2) release during the bear's active time.

Stable water isotopologue ratios in fog and cloud droplets of liquid clouds are not size-dependent

USGS Publications Warehouse

Spiegel, J.K.; Aemisegger, F.; Scholl, M.; Wienhold, F.G.; Collett, J.L.; Lee, T.; van Pinxteren, D.; Mertes, S.; Tilgner, A.; Herrmann, H.; Werner, Roland A.; Buchmann, N.; Eugster, W.

2012-01-01

In this work, we present the first observations of stable water isotopologue ratios in cloud droplets of different sizes collected simultaneously. We address the question whether the isotope ratio of droplets in a liquid cloud varies as a function of droplet size. Samples were collected from a ground intercepted cloud (= fog) during the Hill Cap Cloud Thuringia 2010 campaign (HCCT-2010) using a three-stage Caltech Active Strand Cloud water Collector (CASCC). An instrument test revealed that no artificial isotopic fractionation occurs during sample collection with the CASCC. Furthermore, we could experimentally confirm the hypothesis that the δ values of cloud droplets of the relevant droplet sizes (μm-range) were not significantly different and thus can be assumed to be in isotopic equilibrium immediately with the surrounding water vapor. However, during the dissolution period of the cloud, when the supersaturation inside the cloud decreased and the cloud began to clear, differences in isotope ratios of the different droplet sizes tended to be larger. This is likely to result from the cloud's heterogeneity, implying that larger and smaller cloud droplets have been collected at different moments in time, delivering isotope ratios from different collection times.

Global Carbon Reservoir Oxidative Ratios

NASA Astrophysics Data System (ADS)

Masiello, C. A.; Gallagher, M. E.; Hockaday, W. C.

2010-12-01

Photosynthesis and respiration move carbon and oxygen between the atmosphere and the biosphere at a ratio that is characteristic of the biogeochemical processes involved. This ratio is called the oxidative ratio (OR) of photosynthesis and respiration, and is defined as the ratio of moles of O2 per moles of CO2. This O2/CO2 ratio is a characteristic of biosphere-atmosphere gas fluxes, much like the 13C signature of CO2 transferred between the biosphere and the atmosphere has a characteristic signature. OR values vary on a scale of 0 (CO2) to 2 (CH4), with most ecosystem values clustered between 0.9 and 1.2. Just as 13C can be measured for both carbon fluxes and carbon pools, OR can also be measured for fluxes and pools and can provide information about the processes involved in carbon and oxygen cycling. OR values also provide information about reservoir organic geochemistry because pool OR values are proportional to the oxidation state of carbon (Cox) in the reservoir. OR may prove to be a particularly valuable biogeochemical tracer because of its ability to couple information about ecosystem gas fluxes with ecosystem organic geochemistry. We have developed 3 methods to measure the OR of ecosystem carbon reservoirs and intercalibrated them to assure that they yield accurate, intercomparable data. Using these tools we have built a large enough database of biomass and soil OR values that it is now possible to consider the implications of global patterns in ecosystem OR values. Here we present a map of the natural range in ecosystem OR values and begin to consider its implications. One striking pattern is an apparent offset between soil and biospheric OR values: soil OR values are frequently higher than that of their source biomass. We discuss this trend in the context of soil organic geochemistry and gas fluxes.

Characteristics of the gait adaptation process due to split-belt treadmill walking under a wide range of right-left speed ratios in humans

PubMed Central

Ogawa, Tetsuya; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka

2018-01-01

The adaptability of human bipedal locomotion has been studied using split-belt treadmill walking. Most of previous studies utilized experimental protocol under remarkably different split ratios (e.g. 1:2, 1:3, or 1:4). While, there is limited research with regard to adaptive process under the small speed ratios. It is important to know the nature of adaptive process under ratio smaller than 1:2, because systematic evaluation of the gait adaptation under small to moderate split ratios would enable us to examine relative contribution of two forms of adaptation (reactive feedback and predictive feedforward control) on gait adaptation. We therefore examined a gait behavior due to on split-belt treadmill adaptation under five belt speed difference conditions (from 1:1.2 to 1:2). Gait parameters related to reactive control (stance time) showed quick adjustments immediately after imposing the split-belt walking in all five speed ratios. Meanwhile, parameters related to predictive control (step length and anterior force) showed a clear pattern of adaptation and subsequent aftereffects except for the 1:1.2 adaptation. Additionally, the 1:1.2 ratio was distinguished from other ratios by cluster analysis based on the relationship between the size of adaptation and the aftereffect. Our findings indicate that the reactive feedback control was involved in all the speed ratios tested and that the extent of reaction was proportionally dependent on the speed ratio of the split-belt. On the contrary, predictive feedforward control was necessary when the ratio of the split-belt was greater. These results enable us to consider how a given split-belt training condition would affect the relative contribution of the two strategies on gait adaptation, which must be considered when developing rehabilitation interventions for stroke patients. PMID:29694404

Characteristics of the gait adaptation process due to split-belt treadmill walking under a wide range of right-left speed ratios in humans.

PubMed

Yokoyama, Hikaru; Sato, Koji; Ogawa, Tetsuya; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Kawashima, Noritaka

2018-01-01

The adaptability of human bipedal locomotion has been studied using split-belt treadmill walking. Most of previous studies utilized experimental protocol under remarkably different split ratios (e.g. 1:2, 1:3, or 1:4). While, there is limited research with regard to adaptive process under the small speed ratios. It is important to know the nature of adaptive process under ratio smaller than 1:2, because systematic evaluation of the gait adaptation under small to moderate split ratios would enable us to examine relative contribution of two forms of adaptation (reactive feedback and predictive feedforward control) on gait adaptation. We therefore examined a gait behavior due to on split-belt treadmill adaptation under five belt speed difference conditions (from 1:1.2 to 1:2). Gait parameters related to reactive control (stance time) showed quick adjustments immediately after imposing the split-belt walking in all five speed ratios. Meanwhile, parameters related to predictive control (step length and anterior force) showed a clear pattern of adaptation and subsequent aftereffects except for the 1:1.2 adaptation. Additionally, the 1:1.2 ratio was distinguished from other ratios by cluster analysis based on the relationship between the size of adaptation and the aftereffect. Our findings indicate that the reactive feedback control was involved in all the speed ratios tested and that the extent of reaction was proportionally dependent on the speed ratio of the split-belt. On the contrary, predictive feedforward control was necessary when the ratio of the split-belt was greater. These results enable us to consider how a given split-belt training condition would affect the relative contribution of the two strategies on gait adaptation, which must be considered when developing rehabilitation interventions for stroke patients.

Macronutrient ratios in pollen shape bumble bee (Bombus impatiens) foraging strategies and floral preferences

PubMed Central

Vaudo, Anthony D.; Patch, Harland M.; Mortensen, David A.; Tooker, John F.; Grozinger, Christina M.

2016-01-01

To fuel their activities and rear their offspring, foraging bees must obtain a sufficient quality and quantity of nutritional resources from a diverse plant community. Pollen is the primary source of proteins and lipids for bees, and the concentrations of these nutrients in pollen can vary widely among host-plant species. Therefore we hypothesized that foraging decisions of bumble bees are driven by both the protein and lipid content of pollen. By successively reducing environmental and floral cues, we analyzed pollen-foraging preferences of Bombus impatiens in (i) host-plant species, (ii) pollen isolated from these host-plant species, and (iii) nutritionally modified single-source pollen diets encompassing a range of protein and lipid concentrations. In our semifield experiments, B. impatiens foragers exponentially increased their foraging rates of pollen from plant species with high protein:lipid (P:L) ratios; the most preferred plant species had the highest ratio (∼4.6:1). These preferences were confirmed in cage studies where, in pairwise comparisons in the absence of other floral cues, B. impatiens workers still preferred pollen with higher P:L ratios. Finally, when presented with nutritionally modified pollen, workers were most attracted to pollen with P:L ratios of 5:1 and 10:1, but increasing the protein or lipid concentration (while leaving ratios intact) reduced attraction. Thus, macronutritional ratios appear to be a primary factor driving bee pollen-foraging behavior and may explain observed patterns of host-plant visitation across the landscape. The nutritional quality of pollen resources should be taken into consideration when designing conservation habitats supporting bee populations. PMID:27357683

Mills' ratio

NASA Astrophysics Data System (ADS)

Baricz, Árpád

2008-04-01

In this paper we study the monotonicity properties of some functions involving the Mills' ratio of the standard normal law. From these we deduce some new functional inequalities involving the Mills' ratio, and we show that the Mills' ratio is strictly completely monotonic. At the end of this paper we present some Turán-type inequalities for Mills' ratio.

Synthetic aperture radar range - Azimuth ambiguity design and constraints

NASA Technical Reports Server (NTRS)

Mehlis, J. G.

1980-01-01

Problems concerning the design of a system for mapping a planetary surface with a synthetic aperture radar (SAR) are considered. Given an ambiguity level, resolution, and swath width, the problems are related to the determination of optimum antenna apertures and the most suitable pulse repetition frequency (PRF). From the set of normalized azimuth ambiguity ratio curves, the designer can arrive at the azimuth antenna length, and from the sets of normalized range ambiguity ratio curves, he can arrive at the range aperture length or pulse repetition frequency. A procedure based on this design method is shown in an example. The normalized curves provide results for a SAR using a uniformly or cosine weighted rectangular antenna aperture.

Chloride/bromide ratios in leachate derived from farm-animal waste.

PubMed

Hudak, Paul F

2003-01-01

Ratios of conservative chemicals have been used to identify sources of groundwater contamination. While chloride/bromide ratios have been reported for several common sources of groundwater contamination, little work has been done on leachate derived from farm-animal waste. In this study, chloride/bromide ratios were measured in leachate derived from longhorn-cattle, quarterhorse, and pygme-goat waste at a farm in Abilene, Texas, USA. (Minimum, median, and maximum) chloride/bromide ratios of (66.5, 85.6, and 167), (119, 146, and 156), and (35.4, 57.8, and 165) were observed for cattle, horses, and goats, respectively. These ratios are below typical values for domestic wastewater and within the range commonly observed for oilfield brine. Results of this study have important implications for identifying sources of contaminated groundwater in settings with significant livestock and/or oil production.

Stable isotope ratios of tap water in the contiguous United States

NASA Astrophysics Data System (ADS)

Bowen, Gabriel J.; Ehleringer, James R.; Chesson, Lesley A.; Stange, Erik; Cerling, Thure E.

2007-03-01

Understanding links between water consumers and climatological (precipitation) sources is essential for developing strategies to ensure the long-term sustainability of water supplies. In pursing this understanding a need exists for tools to study and monitor complex human-hydrological systems that involve high levels of spatial connectivity and supply problems that are regional, rather than local, in nature. Here we report the first national-level survey of stable isotope ratios in tap water, including spatially and temporally explicit samples from a large number of cities and towns across the contiguous United States. We show that intra-annual ranges of tap water isotope ratios are relatively small (e.g., <10‰ for δ2H) at most sites. In contrast, spatial variation in tap water isotope ratios is very large, spanning ranges of 163‰ for δ2H and 23.6‰ for δ18O. The spatial distribution of tap water isotope ratios at the national level is similar to that of stable isotope ratios of precipitation. At the regional level, however, pervasive differences between tap water and precipitation isotope ratios can be attributed to hydrological factors in the water source to consumer chain. These patterns highlight the potential for monitoring of tap water isotope ratios to contribute to the study of regional water supply stability and provide warning signals for impending water resource changes. We present the first published maps of predicted tap water isotope ratios for the contiguous United States, which will be useful in guiding future research on human-hydrological systems and as a tool for applied forensics and traceability studies.

Interaction between Trypanosoma rangeli and the Rhodnius prolixus salivary gland depends on the phosphotyrosine ecto-phosphatase activity of the parasite.

PubMed

Dos-Santos, André L A; Dick, Claudia F; Alves-Bezerra, Michele; Silveira, Thaís S; Paes, Lisvane Silva; Gondim, Katia C; Meyer-Fernandes, José R

2012-08-01

Trypanosoma rangeli is the trypanosomatid that colonizes the salivary gland of its insect vector, with a profound impact on the feeding capacity of the insect. In this study we investigated the role of the phosphotyrosine (P-Tyr) ecto-phosphatase activity of T. rangeli in its interaction with Rhodnius prolixus salivary glands. Long but not short epimastigotes adhered to the gland cells and the strength of interaction correlated with the enzyme activity levels in different strains. Differential interference contrast microscopy demonstrated that clusters of parasites are formed in most cases, suggesting cooperative interaction in the adhesion process. The tightness of the correlation was evidenced by modulating the P-Tyr ecto-phosphatase activity with various concentrations of inhibitors. Sodium orthovanadate, ammonium molybdate and zinc chloride decreased the interaction between T. rangeli and R. prolixus salivary glands in parallel. Levamisole, an inhibitor of alkaline phosphatases, affected neither process. EDTA strongly inhibited adhesion and P-Tyr ecto-phosphatase activity to the same extent, an effect that was no longer seen if the parasites were pre-incubated with the chelator and then washed. When the P-Tyr ecto-phosphatase of living T. rangeli epimastigotes was irreversibly inactivated with sodium orthovanadate and the parasite cells were then injected into the insect thorax, colonization of the salivary glands was greatly depressed for several days after blood feeding. Addition of P-Tyr ecto-phosphatase substrates such as p-nitrophenyl phosphate (pNPP) and P-Tyr inhibited the adhesion of T. rangeli to salivary glands, but P-Ser, P-Thr and β-glycerophosphate were completely ineffective. Immunoassays using anti-P-Tyr-residues revealed a large number of P-Tyr-proteins in extracts of R. prolixus salivary glands, which could be potentially targeted by T. rangeli during adhesion. These results indicate that dephosphorylation of structural P-Tyr residues on the

Neoseiulus californicus (Acari: Phytoseiidae) as a potential control agent of Tetranychus urticae (Acari: Tetranychidae): effect of pest/predator ratio on pest abundance on strawberry.

PubMed

Greco, Nancy M; Sánchez, Norma E; Liljesthröm, Gerardo G

2005-01-01

Neoseiulus californicus (McGregor) is a promising agent for successful Tetranychus urticae Koch control through conservation techniques, in strawberry crops in La Plata (Buenos Aires, Argentina). In prey-predator interaction, initial relative densities have an important effect on system dynamics. The economic threshold level (ETL) used for this pest in the present study was 50 active mites per leaflet. In our laboratory experiments, initial T. urticae to N. californicus ratio had a significant effect on the population abundance of T. urticae at a 7-day period. When pest/predator ratio was 5/1 (at initial pest densities from 5 to 15 females/leaflet) the final number of active T. urticae/leaflet was significantly lower than the ETL, while at 20 females/leaflet this number did not differ from the ETL. At 7.5/1 ratio, the final number of active T. urticae/leaflet, at initial pest densities from 5 to 15 females/leaflet, reached the ETL without surpassing it. At 10/1 and 15/1 ratios, pest densities exceeded the ETL only at 15 initial T. urticae/leaflet. Most greenhouse and field observations were consistent with the predictions of a graphical model based on experimental results. This predator was very effective in limiting pest densities at a 7-day period and within the range of pest-predator ratios and absolute densities used in this study. Conservation of N. californicus promoting favorable pest/predator ratios may result in early control of T. urticae.

Determination of phenylalanine isotope ratio enrichment by liquid chromatography/time- of-flight mass spectrometry.

PubMed

Wu, Zhanpin; Zhang, Xiao-Jun; Cody, Robert B; Wolfe, Robert R

2004-01-01

The application of time-of-flight mass spectrometry to isotope ratio measurements has been limited by the relatively low dynamic range of the time-to-digital converter detectors available on commercial LC/ToF-MS systems. Here we report the measurement of phenylalanine isotope ratio enrichment by using a new LC/ToF-MS system with wide dynamic range. Underivatized phenylalanine was injected onto a C18 column directly with 0.1% formic acid/acetonitrile as the mobile phase. The optimal instrument parameters for the time-of-flight mass spectrometer were determined by tuning the instrument with a phenylalanine standard. The accuracy of the isotope enrichment measurement was determined by the injection of standard solutions with known isotope ratios ranging from 0.02% to 9.2%. A plot of the results against the theoretical values gave a linear curve with R2 of 0.9999. The coefficient of variation for the isotope ratio measurement was below 2%. The method is simple, rapid, and accurate and presents an attractive alternative to traditional GC/MS applications.

Pinpointing wastewater and process parameters controlling the AOB to NOB activity ratio in sewage treatment plants.

PubMed

Seuntjens, Dries; Han, Mofei; Kerckhof, Frederiek-Maarten; Boon, Nico; Al-Omari, Ahmed; Takacs, Imre; Meerburg, Francis; De Mulder, Chaïm; Wett, Bernhard; Bott, Charles; Murthy, Sudhir; Carvajal Arroyo, Jose Maria; De Clippeleir, Haydée; Vlaeminck, Siegfried E

2018-07-01

Even though nitrification/denitrification is a robust technology to remove nitrogen from sewage, economic incentives drive its future replacement by shortcut nitrogen removal processes. The latter necessitates high potential activity ratios of ammonia oxidizing to nitrite oxidizing bacteria (rAOB/rNOB). The goal of this study was to identify which wastewater and process parameters can govern this in reality. Two sewage treatment plants (STP) were chosen based on their inverse rAOB/rNOB values (at 20 °C): 0.6 for Blue Plains (BP, Washington DC, US) and 1.6 for Nieuwveer (NV, Breda, NL). Disproportional and dissimilar relationships between AOB or NOB relative abundances and respective activities pointed towards differences in community and growth/activity limiting parameters. The AOB communities showed to be particularly different. Temperature had no discriminatory effect on the nitrifiers' activities, with similar Arrhenius temperature dependences (Θ AOB  = 1.10, Θ NOB  = 1.06-1.07). To uncouple the temperature effect from potential limitations like inorganic carbon, phosphorus and nitrogen, an add-on mechanistic methodology based on kinetic modelling was developed. Results suggest that BP's AOB activity was limited by the concentration of inorganic carbon (not by residual N and P), while NOB experienced less limitation from this. For NV, the sludge-specific nitrogen loading rate seemed to be the most prevalent factor limiting AOB and NOB activities. Altogether, this study shows that bottom-up mechanistic modelling can identify parameters that influence the nitrification performance. Increasing inorganic carbon in BP could invert its rAOB/rNOB value, facilitating its transition to shortcut nitrogen removal. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ranging Behaviour of Commercial Free-Range Laying Hens.

PubMed

Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

2016-04-26

In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

System and method for high precision isotope ratio destructive analysis

DOEpatents

Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

2013-07-02

A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

Chemiluminescence-based multivariate sensing of local equivalence ratios in premixed atmospheric methane-air flames

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tripathi, Markandey M.; Krishnan, Sundar R.; Srinivasan, Kalyan K.

Chemiluminescence emissions from OH*, CH*, C2, and CO2 formed within the reaction zone of premixed flames depend upon the fuel-air equivalence ratio in the burning mixture. In the present paper, a new partial least square regression (PLS-R) based multivariate sensing methodology is investigated and compared with an OH*/CH* intensity ratio-based calibration model for sensing equivalence ratio in atmospheric methane-air premixed flames. Five replications of spectral data at nine different equivalence ratios ranging from 0.73 to 1.48 were used in the calibration of both models. During model development, the PLS-R model was initially validated with the calibration data set using themore » leave-one-out cross validation technique. Since the PLS-R model used the entire raw spectral intensities, it did not need the nonlinear background subtraction of CO2 emission that is required for typical OH*/CH* intensity ratio calibrations. An unbiased spectral data set (not used in the PLS-R model development), for 28 different equivalence ratio conditions ranging from 0.71 to 1.67, was used to predict equivalence ratios using the PLS-R and the intensity ratio calibration models. It was found that the equivalence ratios predicted with the PLS-R based multivariate calibration model matched the experimentally measured equivalence ratios within 7%; whereas, the OH*/CH* intensity ratio calibration grossly underpredicted equivalence ratios in comparison to measured equivalence ratios, especially under rich conditions ( > 1.2). The practical implications of the chemiluminescence-based multivariate equivalence ratio sensing methodology are also discussed.« less

Food consumption, physical activity and socio-economic status related to BMI, waist circumference and waist-to-height ratio in adolescents.

PubMed

Abreu, Sandra; Santos, Rute; Moreira, Carla; Santos, Paula Clara; Mota, Jorge; Moreira, Pedro

2014-08-01

To examine the association between obesity and food group intakes, physical activity and socio-economic status in adolescents. A cross-sectional study was carried out in 2008. Cole's cut-off points were used to categorize BMI. Abdominal obesity was defined by a waist circumference at or above the 90th percentile, as well as a waist-to-height ratio at or above 0·500. Diet was evaluated using an FFQ, and the food group consumption was categorized using sex-specific tertiles of each food group amount. Physical activity was assessed via a self-report questionnaire. Socio-economic status was assessed referring to parental education and employment status. Data were analysed separately for girls and boys and the associations among food consumption, physical activity, socio-economic status and BMI, waist circumference and waist-to-height ratio were evaluated using logistic regression analysis, adjusting the results for potential confounders. Public schools in the Azorean Archipelago, Portugal. Adolescents (n 1209) aged 15-18 years. After adjustment, in boys, higher intake of ready-to-eat cereals was a negative predictor while vegetables were a positive predictor of overweight/obesity and abdominal obesity. Active boys had lower odds of abdominal obesity compared with inactive boys. Boys whose mother showed a low education level had higher odds of abdominal obesity compared with boys whose mother presented a high education level. Concerning girls, higher intake of sweets and pastries was a negative predictor of overweight/obesity and abdominal obesity. Girls in tertile 2 of milk intake had lower odds of abdominal obesity than those in tertile 1. Girls whose father had no relationship with employment displayed higher odds of abdominal obesity compared with girls whose father had high employment status. We have found that different measures of obesity have distinct associations with food group intakes, physical activity and socio-economic status.

Successive ratio subtraction as a novel manipulation of ratio spectra for quantitative determination of a mixture of furosemide, spironolactone and canrenone

NASA Astrophysics Data System (ADS)

Emam, Aml A.; Abdelaleem, Eglal A.; Naguib, Ibrahim A.; Abdallah, Fatma F.; Ali, Nouruddin W.

2018-03-01

Furosemide and spironolactone are commonly prescribed antihypertensive drugs. Canrenone is the main degradation product and main metabolite of spironolactone. Ratio subtraction and extended ratio subtraction spectrophotometric methods were previously applied for quantitation of only binary mixtures. An extension of the above mentioned methods; successive ratio subtraction, is introduced in the presented work for quantitative determination of ternary mixtures exemplified by furosemide, spironolactone and canrenone. Manipulating the ratio spectra of the ternary mixture allowed their determination at 273.6 nm, 285 nm and 240 nm and in the concentration ranges of (2-16 μg mL- 1), (4-32 μg mL- 1) and (1-18 μg mL- 1) for furosemide, spironolactone and canrenone, respectively. Method specificity was ensured by the application to laboratory prepared mixtures. The introduced method was ensured to be accurate and precise. Validation of the developed method was done with respect to ICH guidelines and its validity was further ensured by the application to the pharmaceutical formulation. Statistical comparison between the obtained results and those obtained from the reported HPLC method was achieved concerning student's t-test and F ratio test where no significant difference was observed.

Ratio

NASA Astrophysics Data System (ADS)

Webster, Nathan A. S.; Pownceby, Mark I.; Madsen, Ian C.; Studer, Andrew J.; Manuel, James R.; Kimpton, Justin A.

2014-12-01

Effects of basicity, B (CaO:SiO2 ratio) on the thermal range, concentration, and formation mechanisms of silico-ferrite of calcium and aluminum (SFCA) and SFCA-I iron ore sinter bonding phases have been investigated using an in situ synchrotron X-ray diffraction-based methodology with subsequent Rietveld refinement-based quantitative phase analysis. SFCA and SFCA-I phases are the key bonding materials in iron ore sinter, and improved understanding of the effects of processing parameters such as basicity on their formation and decomposition may assist in improving efficiency of industrial iron ore sintering operations. Increasing basicity significantly increased the thermal range of SFCA-I, from 1363 K to 1533 K (1090 °C to 1260 °C) for a mixture with B = 2.48, to ~1339 K to 1535 K (1066 °C to 1262 °C) for a mixture with B = 3.96, and to ~1323 K to 1593 K (1050 °C to 1320 °C) at B = 4.94. Increasing basicity also increased the amount of SFCA-I formed, from 18 wt pct for the mixture with B = 2.48 to 25 wt pct for the B = 4.94 mixture. Higher basicity of the starting sinter mixture will, therefore, increase the amount of SFCA-I, considered to be more desirable of the two phases. Basicity did not appear to significantly influence the formation mechanism of SFCA-I. It did, however, affect the formation mechanism of SFCA, with the decomposition of SFCA-I coinciding with the formation of a significant amount of additional SFCA in the B = 2.48 and 3.96 mixtures but only a minor amount in the highest basicity mixture. In situ neutron diffraction enabled characterization of the behavior of magnetite after melting of SFCA produced a magnetite plus melt phase assemblage.

Branching Ratios for The Radiometric Calibration of EUNIS-2012

NASA Technical Reports Server (NTRS)

Daw, Adrian N.; Bhatia, A. K.; Rabin, Douglas M.

2012-01-01

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument is a two-channel imaging spectrograph that observes the solar corona and transition region with high spectral resolution and a rapid cadence made possible by unprecedented sensitivity. The upcoming flight will incorporate a new wavelength channel covering the range 524-630 Angstroms, the previously-flown 300-370 Angstroms channel, and the first flight demonstration of cooled active pixel sensor (APS) arrays. The new 524-630 Angstrom channel incorporates a Toroidal Varied Line Space (TVLS) grating coated with B4C/Ir, providing broad spectral coverage and a wide temperature range of 0.025 to 10 MK. Absolute radiometric calibration of the two channels is being performed using a hollow cathode discharge lamp and NIST-calibrated AXUV-100G photodiode. Laboratory observations of He I 584 Angstroms and He II 304 Angstroms provide absolute radiometric calibrations of the two channels at those two respective wavelengths by using the AXUV photodiode as a transfer standard. The spectral responsivity is being determined by observing line pairs with a common upper state in the spectra of Ne I-III and Ar II-III. Calculations of A-values for the observed branching ratios are in progress.

Measuring Poisson Ratios at Low Temperatures

NASA Technical Reports Server (NTRS)

Boozon, R. S.; Shepic, J. A.

1987-01-01

Simple extensometer ring measures bulges of specimens in compression. New method of measuring Poisson's ratio used on brittle ceramic materials at cryogenic temperatures. Extensometer ring encircles cylindrical specimen. Four strain gauges connected in fully active Wheatstone bridge self-temperature-compensating. Used at temperatures as low as liquid helium.

Home range and travels

USGS Publications Warehouse

Stickel, L.F.; King, John A.

1968-01-01

The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

Characterization and Properties of Activated Carbon Prepared from Tamarind Seeds by KOH Activation for Fe(III) Adsorption from Aqueous Solution

PubMed Central

Mopoung, Sumrit; Moonsri, Phansiri; Palas, Wanwimon; Khumpai, Sataporn

2015-01-01

This research studies the characterization of activated carbon from tamarind seed with KOH activation. The effects of 0.5 : 1–1.5 : 1 KOH : tamarind seed charcoal ratios and 500–700°C activation temperatures were studied. FTIR, SEM-EDS, XRD, and BET were used to characterize tamarind seed and the activated carbon prepared from them. Proximate analysis, percent yield, iodine number, methylene blue number, and preliminary test of Fe(III) adsorption were also studied. Fe(III) adsorption was carried out by 30 mL column with 5–20 ppm Fe(III) initial concentrations. The percent yield of activated carbon prepared from tamarind seed with KOH activation decreased with increasing activation temperature and impregnation ratios, which were in the range from 54.09 to 82.03 wt%. The surface functional groups of activated carbon are O–H, C=O, C–O, –CO3, C–H, and Si–H. The XRD result showed high crystallinity coming from a potassium compound in the activated carbon. The main elements found in the activated carbon by EDS are C, O, Si, and K. The results of iodine and methylene blue adsorption indicate that the pore size of the activated carbon is mostly in the range of mesopore and macropore. The average BET pore size and BET surface area of activated carbon are 67.9764 Å and 2.7167 m2/g, respectively. Finally, the tamarind seed based activated carbon produced with 500°C activation temperature and 1.0 : 1 KOH : tamarind seed charcoal ratio was used for Fe(III) adsorption test. It was shown that Fe(III) was adsorbed in alkaline conditions and adsorption increased with increasing Fe(III) initial concentration from 5 to 20 ppm with capacity adsorption of 0.0069–0.019 mg/g. PMID:26689357

Global remote sensing of water-chlorophyll ratio in terrestrial plant leaves.

PubMed

Kushida, Keiji

2012-10-01

I evaluated the use of global remote sensing techniques for estimating plant leaf chlorophyll a + b (C(ab); μg cm(-2)) and water (C(w); mg cm(-2)) concentrations as well as the ratio of C(w)/C(ab) with the PROSAIL model under possible distributions for leaf and soil spectra, leaf area index (LAI), canopy geometric structure, and leaf size. First, I estimated LAI from the normalized difference vegetation index. I found that, at LAI values <2, C(ab), C(w), and C(w)/C(ab) could not be reliably estimated. At LAI values >2, C(ab) and C(w) could be estimated for only restricted ranges of the canopy structure; however, the ratio of C(w)/C(ab) could be reliably estimated for a variety of possible canopy structures with coefficients of determination (R(2)) ranging from 0.56 to 0.90. The remote estimation of the C(w)/C(ab) ratio from satellites offers information on plant condition at a global scale.

Parrotfish sex ratios recover rapidly in Bermuda following a fishing ban

NASA Astrophysics Data System (ADS)

O'Farrell, Shay; Luckhurst, Brian E.; Box, Stephen J.; Mumby, Peter J.

2016-06-01

Parrotfishes are an ecologically and commercially important teleost group whose grazing contributes to maintaining coral-dominated states on hermatypic reefs. However, overfishing has skewed sex ratios of Atlantic parrotfishes because fishing has disproportionate impacts on larger individuals, and males are generally larger than females. Whether protection from fishing may allow sex ratios to return to equilibrium is unknown, as fishing can induce irreversible ecological and/or evolutionary shifts. Bermuda banned trap fishing in 1990, creating a unique opportunity to analyse long-term responses of Atlantic parrotfishes to release from fishing. We found that sex ratios of four common parrotfishes were initially skewed, with male proportions ranging from 0.04 to 0.18. However, male proportions rebounded within 3-4 yr, equilibrating at values ranging from 0.36 to 0.54, similar to those reported at unfished sites in the region. Our results are encouraging for regional efforts to recover lost grazing function by restoring overfished herbivore populations.

Decreased sodium:potassium ratios in cats: 49 cases.

PubMed

Bell, Rory; Mellor, Dominic J; Ramsey, Ian; Knottenbelt, Clare

2005-06-01

Sodium:potassium (Na:K) ratios are often reported in feline biochemical panels, although the importance of this measurement has not been investigated. The aims of this study were to document the range of feline disease states associated with a decreased Na:K ratio, to determine the prevalence of this biochemical abnormality in a referral hospital population, and to identify any particular disease that was more likely to have a decreased Na:K ratio. A group of 49 cats with decreased Na:K ratios was compared with a group of 50 cats with normal Na:K ratios that were randomly selected from the same hospital population. Twelve of the 49 cats (24.5%) had gastrointestinal disease, 10 (20.4%) had urinary disease, 8 (16.3%) had endocrine disease, 8 (16.3%) had cardiorespiratory disease, and 5 (10.0%) had diseases affecting other body systems. Six (12.2%) had artifactually decreased Na:K ratios. No cat was identified with hypoadrenocorticism. Statistical analysis revealed that, although none of these disease states was significantly over- or under-represented in the affected group, a significantly higher proportion of cats with decreased Na:K ratio had body cavity effusions (P = .025). Serum potassium concentrations were significantly higher in the affected group (P < .0001), but there was no significant difference in mean sodium concentration between the 2 groups. Decreased Na:K ratios frequently occur in cats with diseases other than hypoadrenocorticism, including cats with effusions. These findings should be considered when evaluating cats with this biochemical abnormality.

Isotopic ratios D/H and 15N/14N in giant planets

NASA Astrophysics Data System (ADS)

Marboeuf, Ulysse; Thiabaud, Amaury; Alibert, Yann; Benz, Willy

2018-04-01

The determination of isotopic ratios in planets is important since it allows us to investigate the origins and initial composition of materials. The present work aims to determine the possible range of values for isotopic ratios D/H and 15N/14N in giant planets. The main objective is to provide valuable theoretical assumptions on the isotopic composition of giant planets, their internal structure, and the main reservoirs of species. We use models of ice formation and planet formation that compute the composition of ices and gas accreted in the core and the envelope of planets. Assuming a single initial value for isotopic ratios in volatile species, and disruption of planetesimals in the envelope of gaseous planets, we obtain a wide variety of D/H and 15N/14N ratios in low-mass planets (≤100 Mearth) due to the migration pathway of planets, the accretion time of gas species whose relative abundance evolves with time, and isotope exchanges among species. If giant planets with mass greater than 100 Mearth have solar isotopic ratios such as Jupiter and Saturn due to their higher envelope mass, Neptune-type planets present values ranging between one and three times the solar value. It seems therefore difficult to use isotopic ratios in the envelope of these planets to get information about their formation in the disc. For giant planets, the ratios allow us to constrain the mass fraction of volatile species in the envelope needed to reproduce the observational data by assuming initial values for isotopic ratios in volatile species.

Statistical inference for tumor growth inhibition T/C ratio.

PubMed

Wu, Jianrong

2010-09-01

The tumor growth inhibition T/C ratio is commonly used to quantify treatment effects in drug screening tumor xenograft experiments. The T/C ratio is converted to an antitumor activity rating using an arbitrary cutoff point and often without any formal statistical inference. Here, we applied a nonparametric bootstrap method and a small sample likelihood ratio statistic to make a statistical inference of the T/C ratio, including both hypothesis testing and a confidence interval estimate. Furthermore, sample size and power are also discussed for statistical design of tumor xenograft experiments. Tumor xenograft data from an actual experiment were analyzed to illustrate the application.

Integrated optical gyroscope using active Long-range surface plasmon-polariton waveguide resonator

PubMed Central

Zhang, Tong; Qian, Guang; Wang, Yang-Yang; Xue, Xiao-Jun; Shan, Feng; Li, Ruo-Zhou; Wu, Jing-Yuan; Zhang, Xiao-Yang

2014-01-01

Optical gyroscopes with high sensitivity are important rotation sensors for inertial navigation systems. Here, we present the concept of integrated resonant optical gyroscope constructed by active long-range surface plasmon-polariton (LRSPP) waveguide resonator. In this gyroscope, LRSPP waveguide doped gain medium is pumped to compensate the propagation loss, which has lower pump noise than that of conventional optical waveguide. Peculiar properties of single-polarization of LRSPP waveguide have been found to significantly reduce the polarization error. The metal layer of LRSPP waveguide is electro-optical multiplexed for suppression of reciprocal noises. It shows a limited sensitivity of ~10−4 deg/h, and a maximum zero drift which is 4 orders of magnitude lower than that constructed by conventional single-mode waveguide. PMID:24458281

Selected control events and reporting odds ratio in signal detection methodology.

PubMed

Ooba, Nobuhiro; Kubota, Kiyoshi

2010-11-01

To know whether the reporting odds ratio (ROR) using "control events" can detect signals hidden behind striking reports on one or more particular events. We used data of 956 drug use investigations (DUIs) conducted between 1970 and 1998 in Japan and domestic spontaneous reports (SRs) between 1998 and 2008. The event terms in DUIs were converted to the preferred terms in Medical Dictionary for Regulatory Activities (MedDRA). We calculated the incidence proportion for various events and selected 20 "control events" with a relatively constant incidence proportion across DUIs and also reported regularly to the spontaneous reporting system. A "signal" was generated for the drug-event combination when the lower limit of 95% confidence interval of the ROR exceeded 1. We also compared the ROR in SRs with the RR in DUIs. The "control events" accounted for 18.2% of all reports. The ROR using "control events" may detect some hidden signals for a drug with the proportion of "control events" lower than the average. The median of the ratios of the ROR using "control events" to RR was around the unity indicating that "control events" roughly represented the exposure distribution though the range of the ratios was so diverse that the individual ROR might not be regarded as the estimate of RR. The use of the ROR with "control events" may give an adjunctive to the traditional signal detection methods to find a signal hidden behind some major events. Copyright © 2010 John Wiley & Sons, Ltd.

STATISTICAL CHARACTERISTICS OF ELEMENTAL ABUNDANCE RATIOS: OBSERVATIONS FROM THE ACE SPACECRAFT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, L.-L.; Zhang, H.

We statistically analyze the elemental galactic cosmic ray (GCR) composition measurements of elements 5 ≤ Z ≤ 28 within the energy range 30–500 MeV/nucleon from the CRIS instrument on board the ACE spacecraft in orbit about the L1 Lagrange point during the period from 1997 to 2014. Similarly to the last unusual solar minimum, the elevated elemental intensities of all heavy nuclei during the current weak solar maximum in 2014 are ∼40% higher than that of the previous solar maximum in 2002, which has been attributed to the weak modulation associated with low solar activity levels during the ongoing weakestmore » solar maximum since the dawn of space age. In addition, the abundance ratios of heavy nuclei with respect to elemental oxygen are generally independent of kinetic energy per nucleon in the energy region 60–200 MeV/nuc, in good agreement with previous experiments. Furthermore, the abundance ratios of most relatively abundant species, except carbon, exhibit considerable solar-cycle variation, which are obviously positively correlated with the sunspot numbers with about one-year time lag. We also find that the percentage variation of abundance ratios for most elements are approximately identical. These preliminary results provide valuable insights into the characteristics of elemental heavy nuclei composition and place new and significant constraints on future GCR heavy nuclei propagation and modulation models.« less

Long‐term trends in fall age ratios of black brant

USGS Publications Warehouse

Ward, David H.; Amundson, Courtney L.; Stehn, Robert A.; Dau, Christian P.

2018-01-01

Accurate estimates of the age composition of populations can inform past reproductive success and future population trajectories. We examined fall age ratios (juveniles:total birds) of black brant (Branta bernicla nigricans; brant) staging at Izembek National Wildlife Refuge near the tip of the Alaska Peninsula, southwest Alaska, USA, 1963 to 2015. We also investigated variation in fall age ratios associated with sampling location, an index of flock size, survey effort, day of season, observer, survey platform (boat‐ or land‐based) and tide stage. We analyzed data using logistic regression models implemented in a Bayesian framework. Mean predicted fall age ratio controlling for survey effort, day of year, and temporal and spatial variation was 0.24 (95% CL = 0.23, 0.25). Overall trend in age ratios was −0.6% per year (95% CL = −1.3%, 0.2%), resulting in an approximate 26% decline in the proportion of juveniles over the study period. We found evidence for variation across a range of variables implying that juveniles are not randomly distributed in space and time within Izembek Lagoon. Age ratios varied by location within the study area and were highly variable among years. They decreased with the number of birds aged (an index of flock size) and increased throughout September before leveling off in early October and declining in late October. Age ratios were similar among tide stages and observers and were lower during boat‐based (offshore) than land‐based (nearshore) surveys. Our results indicate surveys should be conducted annually during early to mid‐October to ensure the entire population is present and available for sampling, and throughout Izembek Lagoon to account for spatiotemporal variation in age ratios. Sampling should include a wide range of flock sizes representative of their distribution and occur in flocks located near and off shore. Further research evaluating the cause of declining age ratios in the fall population is necessary

Stable oxygen and hydrogen isotopes of brines - comparing isotope ratio mass spectrometry and isotope ratio infrared spectroscopy

NASA Astrophysics Data System (ADS)

Ahrens, Christian; Koeniger, Paul; van Geldern, Robert; Stadler, Susanne

2013-04-01

Today's standard analytical methods for high precision stable isotope analysis of fluids are gas-water equilibration and high temperature pyrolysis coupled to isotope ratio mass spectrometers (IRMS). In recent years, relatively new laser-based analytical instruments entered the market that are said to allow high isotope precision data on nearly every media. This optical technique is referred to as isotope ratio infrared spectroscopy (IRIS). The objective of this study is to evaluate the capability of this new instrument type for highly saline solutions and a comparison of the analytical results with traditional IRMS analysis. It has been shown for the equilibration method that the presence of salts influences the measured isotope values depending on the salt concentration (see Lécuyer et al, 2009; Martineau, 2012). This so-called 'isotope salt effect' depends on the salt type and salt concentration. These factors change the activity in the fluid and therefore shift the isotope ratios measured by the equilibration method. Consequently, correction factors have to be applied to these analytical data. Direct conversion techniques like pyrolysis or the new laser instruments allow the measurement of the water molecule from the sample directly and should therefore not suffer from the salt effect, i.e. no corrections of raw values are necessary. However, due to high salt concentrations this might cause technical problems with the analytical hardware and may require labor-intensive sample preparation (e.g. vacuum distillation). This study evaluates the salt isotope effect for the IRMS equilibration technique (Thermo Gasbench II coupled to Delta Plus XP) and the laser-based IRIS instruments with liquid injection (Picarro L2120-i). Synthetic salt solutions (NaCl, KCl, CaCl2, MgCl2, MgSO4, CaSO4) and natural brines collected from the Stassfurt Salt Anticline (Germany; Stadler et al., 2012) were analysed with both techniques. Salt concentrations ranged from seawater salinity

Method to estimate the effective temperatures of late-type giants using line-depth ratios in the wavelength range 0.97-1.32 μm

NASA Astrophysics Data System (ADS)

Taniguchi, Daisuke; Matsunaga, Noriyuki; Kobayashi, Naoto; Fukue, Kei; Hamano, Satoshi; Ikeda, Yuji; Kawakita, Hideyo; Kondo, Sohei; Sameshima, Hiroaki; Yasui, Chikako

2018-02-01

The effective temperature, one of the most fundamental atmospheric parameters of a star, can be estimated using various methods; here, we focus on a method using line-depth ratios (LDRs). This method combines low- and high-excitation lines and makes use of relations between LDRs of these line pairs and the effective temperature. It has an advantage, for example, of being minimally affected by interstellar reddening, which changes stellar colours. We report 81 relations between LDRs and effective temperature established with high-resolution, λ/Δλ ∼ 28 000, spectra of nine G- to M-type giants in the Y and J bands. Our analysis gives the first comprehensive set of LDR relations for this wavelength range. The combination of all these relations can be used to determine the effective temperatures of stars that have 3700 < Teff < 5400 K and -0.5 < [Fe/H] < +0.3 dex, to a precision of ±10 K in the best cases.

Isotopic ratio and vertical distribution of radionuclides in soil affected by the accident of Fukushima Dai-ichi nuclear power plants.

PubMed

Fujiwara, Takeshi; Saito, Takumi; Muroya, Yusa; Sawahata, Hiroyuki; Yamashita, Yuji; Nagasaki, Shinya; Okamoto, Koji; Takahashi, Hiroyuki; Uesaka, Mitsuru; Katsumura, Yosuke; Tanaka, Satoru

2012-11-01

The results of γ analyses of soil samples obtained from 50 locations in Fukushima prefecture on April 20, 2011, revealed the presence of a spectrum of radionuclides resulted from the accident of the Fukushima Dai-ichi nuclear power plant (FDNPP). The sum γ radioactivity concentration ranged in more than 3 orders of magnitude, depending on the sampling locations. The contamination of soils in the northwest of the FDNPP was considerable. The (131)I/(137)Cs activity ratios of the soil samples plotted as a function of the distance from the F1 NPPs exhibited three distinctive patterns. Such patterns would reflect not only the different deposition behaviors of these radionuclides, but also on the conditions of associated release events such as temperature and compositions and physicochemical forms of released radionuclides. The (136)Cs/(137)Cs activity ratio, on the other hand, was considered to only reflect the difference in isotopic compositions of source materials. Two locations close to the NPP in the northwest direction were found to be depleted in short-lived (136)Cs. This likely suggested the presence of distinct sources with different (136)Cs/(137)Cs isotopic ratios, although their details were unknown at present. Vertical γ activity profiles of (131)I and (137)Cs were also investigated, using 20-30 cm soil cores in several locations. About 70% or more of the radionuclides were present in the uppermost 2-cm regions. It was found that the profiles of (131)I/(137)Cs activity ratios showed maxima in the 2-4 cm regions, suggesting slightly larger migration of the former nuclide. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mapping and defining sources of variability in bioavailable strontium isotope ratios in the Eastern Mediterranean

NASA Astrophysics Data System (ADS)

Hartman, Gideon; Richards, Mike

2014-02-01

The relative contributions of bedrock and atmospheric sources to bioavailable strontium (Sr) pools in local soils was studied in Northern Israel and the Golan regions through intensive systematic sampling of modern plants and invertebrates, to produce a map of modern bioavailable strontium isotope ratios (87Sr/86Sr) for regional reconstructions of human and animal mobility patterns. The study investigates sources of variability in bioavailable 87Sr/86Sr ratios, in particular the intra-and inter-site range of variation in plant 87Sr/86Sr ratios, the range of 87Sr/86Sr ratios of plants growing on marine sedimentary versus volcanic geologies, the differences between ligneous and non-ligneous plants with varying growth and water utilization strategies, and the relative contribution of atmospheric Sr sources from different soil and vegetation types and climatic zones. Results indicate predictable variation in 87Sr/86Sr ratios. Inter- and intra-site differences in bioavailable 87Sr/86Sr ratios average of 0.00025, while the range of 87Sr/86Sr ratios measured regionally in plants and invertebrates is 0.7090 in Pleistocene calcareous sandstone and 0.7074 in mid-Pleistocene volcanic pyroclast. The 87Sr/86Sr ratios measured in plants growing on volcanic bedrock show time dependent increases in atmospheric deposition relative to bedrock weathering. The 87Sr/86Sr ratios measured in plants growing on renzina soils depends on precipitation. The spacing between bedrock 87Sr/86Sr ratios and plants is highest in wet conditions and decreases in dry conditions. The 87Sr/86Sr ratios measured in plants growing on terra rossa soils is relatively constant (0.7085) regardless of precipitation. Ligneous plants are typically closer to bedrock 87Sr/86Sr ratios than non-ligneous plants. Since the bioavailable 87Sr/86Sr ratios currently measured in the region reflect a mix of both exogenous and endogenous sources, changes in the relative contribution of exogenous sources can cause variation

Use of ICP/MS with ultrasonic nebulizer for routine determination of uranium activity ratios in natural water

USGS Publications Warehouse

Kraemer, T.F.; Doughten, M.W.; Bullen, T.D.

2002-01-01

A method is described that allows precise determination of 234U/238U activity ratios (UAR) in most natural waters using commonly available inductively coupled plasma/mass spectrometry (ICP/MS) instrumentation and accessories. The precision achieved by this technique (??0.5% RSD, 1 sigma) is intermediate between thermal ionization mass spectrometry (??0.25% RSID, 1 sigma) and alpha particle spectrometry (??5% RSD, 1 sigma). It is precise and rapid enough to allow analysis of a large number of samples in a short period of time at low cost using standard, commercially available quadrupole instrumentation with ultrasonic nebulizer and desolvator accessories. UARs have been analyzed successfully in fresh to moderately saline waters with U concentrations of from less than 1 ??g/L to nearly 100 ??g/L. An example of the uses of these data is shown for a study of surface-water mixing in the North Platte River in western Nebraska. This rapid and easy technique should encourage the wider use of uranium isotopes in surface-water and groundwater investigations, both for qualitative (e.g. identifying sources of water) and quantitative (e.g. determining end-member mixing ratios purposes.

Likelihood ratio decisions in memory: three implied regularities.

PubMed

Glanzer, Murray; Hilford, Andrew; Maloney, Laurence T

2009-06-01

We analyze four general signal detection models for recognition memory that differ in their distributional assumptions. Our analyses show that a basic assumption of signal detection theory, the likelihood ratio decision axis, implies three regularities in recognition memory: (1) the mirror effect, (2) the variance effect, and (3) the z-ROC length effect. For each model, we present the equations that produce the three regularities and show, in computed examples, how they do so. We then show that the regularities appear in data from a range of recognition studies. The analyses and data in our study support the following generalization: Individuals make efficient recognition decisions on the basis of likelihood ratios.

The complexity of hair/blood mercury concentration ratios and its implications.

PubMed

Liberda, Eric N; Tsuji, Leonard J S; Martin, Ian D; Ayotte, Pierre; Dewailly, Eric; Nieboer, Evert

2014-10-01

The World Health Organization (WHO) recommends a mercury (Hg) hair-to-blood ratio of 250 for the conversion of Hg hair levels to those in whole blood. This encouraged the selection of hair as the preferred analyte because it minimizes collection, storage, and transportation issues. In spite of these advantages, there is concern about inherent uncertainties in the use of this ratio. To evaluate the appropriateness of the WHO ratio, we investigated total hair and total blood Hg concentrations in 1333 individuals from 9 First Nations (Aboriginal) communities in northern Québec, Canada. We grouped participants by sex, age, and community and performed a 3-factor (M)ANOVA for total Hg in hair (0-2 cm), total Hg in blood, and their ratio. In addition, we calculated the percent error associated with the use of the WHO ratio in predicting blood Hg concentrations from hair Hg. For group comparisons, Estimated Marginal Means (EMMS) were calculated following ANOVA. At the community level, the error in blood Hg estimated from hair Hg ranged -25% to +24%. Systematic underestimation (-8.4%) occurred for females and overestimation for males (+5.8%). At the individual level, the corresponding error range was -98.7% to 1040%, with observed hair-to-blood ratios spanning 3 to 2845. The application of the ratio endorsed by the WHO would be unreliable for determining individual follow-up. We propose that Hg exposure be assessed by blood measurements when there are human health concerns, and that the singular use of hair and the hair-to-blood concentration conversion be discouraged in establishing individual risk. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

The Effect of Cooling Passage Aspect Ratio on Curvature Heat Transfer Enhancement

NASA Technical Reports Server (NTRS)

Meyer, Michael L.

1997-01-01

A series of electrically heated tube experiments was performed to investigate the effect of high aspect ratio on curvature heat transfer enhancement in uniformly heated rectangular cooling passages. Three hardware geometries were tested: a baseline straight aspect ratio 10 tube, an aspect ratio 1 (square) tube with a 45 deg. curve, and an aspect ratio 10 tube with a 45 deg. curve. Gaseous nitrogen with the following properties was used as the coolant: ambient inlet temperature, pressures to 8.3 MPa, wall-to-bulk temperature ratios less than two, and Reynolds numbers based on hydraulic diameter ranging from 250,000 to 1,600,000. The measured curvature enhancement factors were compared to values predicted by three previously published models which had been developed for low aspect ratio tubes. The models were shown to be valid for the high aspect ratio tube as well the low aspect ratio tube, indicating that aspect ratio had little impact on the curvature heat transfer enhancement in these tests.

LTR12 promoter activation in a broad range of human tumor cells by HDAC inhibition

PubMed Central

Krönung, Sonja K.; Beyer, Ulrike; Chiaramonte, Maria Luisa; Dolfini, Diletta; Mantovani, Roberto; Dobbelstein, Matthias

2016-01-01

A considerable proportion of the human genome consists of transposable elements, including the long terminal repeats (LTRs) of endogenous retroviruses. During evolution, such LTRs were occasionally inserted upstream of protein-coding genes, contributing to their regulation. We previously identified the LTR12 from endogenous retrovirus 9 (ERV9) as a regulator of proapoptotic genes such as TP63 or TNFRSF10B. The promoter activity of LTR12 is largely confined to the testes, silenced in testicular carcinoma, but reactivated in testicular cancer cells by broad-range histone deacetylase (HDAC) inhibitors. Here we show that inhibition of HDAC1-3 is sufficient for LTR12 activation. Importantly, HDAC inhibitors induce LTR12 activity not only in testicular cancer cells, but also in cells derived from many additional tumor species. Finally, we characterize the transcription factor NF-Y as a mediator of LTR12 promoter activity and HDAC inhibitor-induced apoptosis, in the context of widespread genomic binding of NF-Y to specific LTR12 sequences. Thus, HDAC inhibitor-driven LTR12 activation represents a generally applicable means to induce proapoptotic genes in human cancer cells. PMID:27172897

Breeding sex ratios in adult leatherback turtles (Dermochelys coriacea) may compensate for female-biased hatchling sex ratios.

PubMed

Stewart, Kelly R; Dutton, Peter H

2014-01-01

For vertebrates with temperature-dependent sex determination, primary (or hatchling) sex ratios are often skewed, an issue of particular relevance to concerns over effects of climate change on populations. However, the ratio of breeding males to females, or the operational sex ratio (OSR), is important to understand because it has consequences for population demographics and determines the capacity of a species to persist. The OSR also affects mating behaviors and mate choice, depending on the more abundant sex. For sea turtles, hatchling and juvenile sex ratios are generally female-biased, and with warming nesting beach temperatures, there is concern that populations may become feminized. Our purpose was to evaluate the breeding sex ratio for leatherback turtles at a nesting beach in St. Croix, USVI. In 2010, we sampled nesting females and later sampled their hatchlings as they emerged from nests. Total genomic DNA was extracted and all individuals were genotyped using 6 polymorphic microsatellite markers. We genotyped 662 hatchlings from 58 females, matching 55 females conclusively to their nests. Of the 55, 42 females mated with one male each, 9 mated with 2 males each and 4 mated with at least 3 males each, for a multiple paternity rate of 23.6%. Using GERUD1.0, we reconstructed parental genotypes, identifying 47 different males and 46 females for an estimated breeding sex ratio of 1.02 males for every female. Thus we demonstrate that there are as many actively breeding males as females in this population. Concerns about female-biased adult sex ratios may be premature, and mate choice or competition may play more of a role in sea turtle reproduction than previously thought. We recommend monitoring breeding sex ratios in the future to allow the integration of this demographic parameter in population models.

Breeding Sex Ratios in Adult Leatherback Turtles (Dermochelys coriacea) May Compensate for Female-Biased Hatchling Sex Ratios

PubMed Central

Stewart, Kelly R.; Dutton, Peter H.

2014-01-01

For vertebrates with temperature-dependent sex determination, primary (or hatchling) sex ratios are often skewed, an issue of particular relevance to concerns over effects of climate change on populations. However, the ratio of breeding males to females, or the operational sex ratio (OSR), is important to understand because it has consequences for population demographics and determines the capacity of a species to persist. The OSR also affects mating behaviors and mate choice, depending on the more abundant sex. For sea turtles, hatchling and juvenile sex ratios are generally female-biased, and with warming nesting beach temperatures, there is concern that populations may become feminized. Our purpose was to evaluate the breeding sex ratio for leatherback turtles at a nesting beach in St. Croix, USVI. In 2010, we sampled nesting females and later sampled their hatchlings as they emerged from nests. Total genomic DNA was extracted and all individuals were genotyped using 6 polymorphic microsatellite markers. We genotyped 662 hatchlings from 58 females, matching 55 females conclusively to their nests. Of the 55, 42 females mated with one male each, 9 mated with 2 males each and 4 mated with at least 3 males each, for a multiple paternity rate of 23.6%. Using GERUD1.0, we reconstructed parental genotypes, identifying 47 different males and 46 females for an estimated breeding sex ratio of 1.02 males for every female. Thus we demonstrate that there are as many actively breeding males as females in this population. Concerns about female-biased adult sex ratios may be premature, and mate choice or competition may play more of a role in sea turtle reproduction than previously thought. We recommend monitoring breeding sex ratios in the future to allow the integration of this demographic parameter in population models. PMID:24505403

Optimal design of an activated sludge plant: theoretical analysis

NASA Astrophysics Data System (ADS)

Islam, M. A.; Amin, M. S. A.; Hoinkis, J.

2013-06-01

The design procedure of an activated sludge plant consisting of an activated sludge reactor and settling tank has been theoretically analyzed assuming that (1) the Monod equation completely describes the growth kinetics of microorganisms causing the degradation of biodegradable pollutants and (2) the settling characteristics are fully described by a power law. For a given reactor height, the design parameter of the reactor (reactor volume) is reduced to the reactor area. Then the sum total area of the reactor and the settling tank is expressed as a function of activated sludge concentration X and the recycled ratio α. A procedure has been developed to calculate X opt, for which the total required area of the plant is minimum for given microbiological system and recycled ratio. Mathematical relations have been derived to calculate the α-range in which X opt meets the requirements of F/ M ratio. Results of the analysis have been illustrated for varying X and α. Mathematical formulae have been proposed to recalculate the recycled ratio in the events, when the influent parameters differ from those assumed in the design.

30 CFR 7.87 - Test to determine the maximum fuel-air ratio.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Test to determine the maximum fuel-air ratio. 7... Use in Underground Coal Mines § 7.87 Test to determine the maximum fuel-air ratio. (a) Test procedure... range that will be used during this test. (3) While running the engine, the following shall apply: (i...

30 CFR 7.87 - Test to determine the maximum fuel-air ratio.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test to determine the maximum fuel-air ratio. 7... Use in Underground Coal Mines § 7.87 Test to determine the maximum fuel-air ratio. (a) Test procedure... range that will be used during this test. (3) While running the engine, the following shall apply: (i...

30 CFR 7.87 - Test to determine the maximum fuel-air ratio.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Test to determine the maximum fuel-air ratio. 7... Use in Underground Coal Mines § 7.87 Test to determine the maximum fuel-air ratio. (a) Test procedure... range that will be used during this test. (3) While running the engine, the following shall apply: (i...

30 CFR 7.87 - Test to determine the maximum fuel-air ratio.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Test to determine the maximum fuel-air ratio. 7... Use in Underground Coal Mines § 7.87 Test to determine the maximum fuel-air ratio. (a) Test procedure... range that will be used during this test. (3) While running the engine, the following shall apply: (i...

30 CFR 7.87 - Test to determine the maximum fuel-air ratio.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Test to determine the maximum fuel-air ratio. 7... Use in Underground Coal Mines § 7.87 Test to determine the maximum fuel-air ratio. (a) Test procedure... range that will be used during this test. (3) While running the engine, the following shall apply: (i...

The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures

NASA Astrophysics Data System (ADS)

Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

2016-09-01

Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H2) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H2/CH4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately larger than 40 for abiotic methane and values of <40 for biotic methane. The definition of the criterion was based on two serpentinization experiments at 200 °C and 0.3 kbar. However, it is not clear whether the criterion is applicable at a wider range of temperatures. In this study, we performed sixteen experiments at 311-500 °C and 3.0 kbar using natural ground peridotite. Our results demonstrate that the H2/CH4 ratios strongly depend on temperature. At 311 °C and 3.0 kbar, the H2/CH4 ratios ranged from 58 to 2,120, much greater than the critical value of 40. By contrast, at 400-500 °C, the H2/CH4 ratios were much lower, ranging from 0.1 to 8.2. The results of this study suggest that the H2/CH4 ratios cannot reliably discriminate abiotic from biotic methane.

The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures

PubMed Central

Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

2016-01-01

Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H2) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H2/CH4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately larger than 40 for abiotic methane and values of <40 for biotic methane. The definition of the criterion was based on two serpentinization experiments at 200 °C and 0.3 kbar. However, it is not clear whether the criterion is applicable at a wider range of temperatures. In this study, we performed sixteen experiments at 311–500 °C and 3.0 kbar using natural ground peridotite. Our results demonstrate that the H2/CH4 ratios strongly depend on temperature. At 311 °C and 3.0 kbar, the H2/CH4 ratios ranged from 58 to 2,120, much greater than the critical value of 40. By contrast, at 400–500 °C, the H2/CH4 ratios were much lower, ranging from 0.1 to 8.2. The results of this study suggest that the H2/CH4 ratios cannot reliably discriminate abiotic from biotic methane. PMID:27666288

The H2/CH4 ratio during serpentinization cannot reliably identify biological signatures.

PubMed

Huang, Ruifang; Sun, Weidong; Liu, Jinzhong; Ding, Xing; Peng, Shaobang; Zhan, Wenhuan

2016-09-26

Serpentinization potentially contributes to the origin and evolution of life during early history of the Earth. Serpentinization produces molecular hydrogen (H 2 ) that can be utilized by microorganisms to gain metabolic energy. Methane can be formed through reactions between molecular hydrogen and oxidized carbon (e.g., carbon dioxide) or through biotic processes. A simple criterion, the H 2 /CH 4 ratio, has been proposed to differentiate abiotic from biotic methane, with values approximately larger than 40 for abiotic methane and values of <40 for biotic methane. The definition of the criterion was based on two serpentinization experiments at 200 °C and 0.3 kbar. However, it is not clear whether the criterion is applicable at a wider range of temperatures. In this study, we performed sixteen experiments at 311-500 °C and 3.0 kbar using natural ground peridotite. Our results demonstrate that the H 2 /CH 4 ratios strongly depend on temperature. At 311 °C and 3.0 kbar, the H 2 /CH 4 ratios ranged from 58 to 2,120, much greater than the critical value of 40. By contrast, at 400-500 °C, the H 2 /CH 4 ratios were much lower, ranging from 0.1 to 8.2. The results of this study suggest that the H 2 /CH 4 ratios cannot reliably discriminate abiotic from biotic methane.

Effect of substrate temperature and V/III flux ratio on In incorporation for InGaN/GaN heterostructures grown by plasma-assisted molecular-beam epitaxy

NASA Astrophysics Data System (ADS)

O'Steen, M. L.; Fedler, F.; Hauenstein, R. J.

1999-10-01

Reflection high-energy electron diffraction (RHEED) and laterally spatially resolved high resolution x-ray diffraction (HRXRD) have been used to identify and characterize rf plasma-assisted molecular-beam epitaxial growth factors which strongly affect the efficiency of In incorporation into InxGa1-xN epitaxial materials. HRXRD results for InxGa1-xN/GaN superlattices reveal a particularly strong dependence of average alloy composition x¯ upon both substrate growth temperature and incident V/III flux ratio. For fixed flux ratio, results reveal a strong thermally activated behavior, with over an order-of-magnitude decrease in x¯ with increasing growth temperature within the narrow range 590-670 °C. Within this same range, a further strong dependence upon V/III flux ratio is observed. The decreased In incorporation at elevated substrate temperatures is tentatively attributed to In surface-segregation and desorption processes. RHEED observations support this segregation/desorption interpretation to account for In loss.

Neotectonic Activity from Karewa Sediments, Kashmir Himalaya, India

NASA Astrophysics Data System (ADS)

Agarwal, K. K.; Shah, R. A.; Achyuthan, H.; Singh, D. S.; Srivastava, S.; Khan, I.

2018-01-01

Intermontane basin sedimentation occurred during Pliocene-Pleistocene in the Karewa Basin which formed after the continent-continent collision resulting in the formation of Himalayan orogenic belt around Eocene. These are elongated, narrow, thrust bounded basins which have formed during the late stages of orogeny. Situated at a height of 1700-1800 m above sea level, the Karewa basin received sediments because of ponding of a pre-existing river system and the tectonic movements along the Great Himalayan Ranges in the north and the Pir-Panjal ranges in the south along active faults. About 1300 m thick sediments of largely fluvio-lacustrine, glacio-fluvio-lacustrine and eolian origin are exposed having evidences of neotectonically formed structural features such as folds and faults. Folds are more prominent in the Lower Karewa formation (Hirpur Formation) while faults (mostly normal faults) are abundant in the Upper Karewas (Nagum Formation). Drainage in the area varies from dendritic to anastomosing to parallel. Anastomosing drainage suggests sudden decrease in gradient while presence of linear features such as faults and ridges is evident by parallel drainage. Study of morphometric parameters such as stream length (Lsm) and stream length ratios (RL), bifurcation ratio (Rb), drainage density (D), form factor (Rf), circularity ratio (Rc), and elongation ratio (Re) also indicate intense tectonic activity in the recent past.

Leaf and root C-to-N ratios are poor predictors of soil microbial biomass C and respiration across 32 tree species.

PubMed

Ferlian, Olga; Wirth, Christian; Eisenhauer, Nico

2017-11-01

Soil microorganisms are the main primary decomposers of plant material and drive biogeochemical processes like carbon and nitrogen cycles. Hence, knowledge of their nutritional demands and limitations for activity and growth is of particular importance. However, potential effects of the stoichiometry of soil and plant species on soil microbial activity and carbon use efficiency are poorly understood. Soil properties and plant traits are assumed to drive microbial carbon and community structure. We investigated the associations between C and N concentrations of leaf, root, and soil as well as their ratios and soil microbial biomass C and activity (microbial basal respiration and specific respiratory quotient) across 32 young native angiosperm tree species at two locations in Central Germany. Correlations between C:N ratios of leaves, roots, and soil were positive but overall weak. Only regressions between root and leaf C:N ratios as well as between root and soil C:N ratios were significant at one site. Soil microbial properties differed significantly between the two sites and were significantly correlated with soil C:N ratio across sites. Soil C concentrations rather than N concentrations drove significant effects of soil C:N ratio on soil microbial properties. No significant correlations between soil microbial properties and leaf as well as root C:N ratios were found. We found weak correlations of C:N ratios between plant aboveground and belowground tissues. Furthermore, microorganisms were not affected by the stoichiometry of plant tissues in the investigated young trees. The results suggest that soil stoichiometry represents a consistent determinant of soil microbial biomass and respiration. Our study indicates that stoichiometric relationships among tree organs can be weak and poor predictors of soil microbial properties in young tree stands. Further research in controlled experimental settings with a wide range of tree species is needed to study the role of

Topology Optimized Architectures with Programmable Poisson's Ratio over Large Deformations.

PubMed

Clausen, Anders; Wang, Fengwen; Jensen, Jakob S; Sigmund, Ole; Lewis, Jennifer A

2015-10-07

Topology optimized architectures are designed and printed with programmable Poisson's ratios ranging from -0.8 to 0.8 over large deformations of 20% or more. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Lunar phase function effects on spectral ratios used for resource assessment

NASA Technical Reports Server (NTRS)

Larson, S. M.; Collins, J.; Singer, R. B.; Johnson, J. R.; Melendrez, D. E.

1993-01-01

Groundbased telescopic CCD images of 36 selected locations on the moon were obtained in five 'standard' bandpasses at 12 phase angles ranging from -78 deg to +75 deg to measure phase function effects on the ratio values used to quantify the abundance of TiO2 and qualitatively indicate soil maturity. Consistent with previous studies, we find that the moon is 'bluer' at small phase angles, but that the effect on the ratio values for TiO2 abundance for the phase angles of our data is on the order of the measurement uncertainties throughout the range of abundances found in the mare. The effect is more significant as seen from orbiting spacecraft over a range of selenographic latitude. Spectral ratio images (400/560 and 400/730 nm) were used to map the abundance of TiO2 using the empirical relation found by Charlette et al from analysis of returned lunar soils. Additionally, the 950/560 and 950/730 nm image ratios were used to define the regions of mature mare soil in which the relation is valid. Although the phase function dependence on wavelength was investigated and quantified for small areas and the integrated disc, the effect specifically on TiO2 mapping was not rigorously determined. For consistency and convenience in observing the whole lunar front side, our mapping utilized images taken -15 deg less than alpha less than 15 deg when the moon was fully illuminated from earth; however, this includes the strong opposition peak.

Placental Adaptation: What Can We Learn from Birthweight:Placental Weight Ratio?

PubMed Central

Hayward, Christina E.; Lean, Samantha; Sibley, Colin P.; Jones, Rebecca L.; Wareing, Mark; Greenwood, Susan L.; Dilworth, Mark R.

2016-01-01

Appropriate fetal growth relies upon adequate placental nutrient transfer. Birthweight:placental weight ratio (BW:PW ratio) is often used as a proxy for placental efficiency, defined as the grams of fetus produced per gram placenta. An elevated BW:PW ratio in an appropriately grown fetus (small placenta) is assumed to be due to up-regulated placental nutrient transfer capacity i.e., a higher nutrient net flux per gram placenta. In fetal growth restriction (FGR), where a fetus fails to achieve its genetically pre-determined growth potential, placental weight and BW:PW ratio are often reduced which may indicate a placenta that fails to adapt its nutrient transfer capacity to compensate for its small size. This review considers the literature on BW:PW ratio in both large cohort studies of normal pregnancies and those studies offering insight into the relationship between BW:PW ratio and outcome measures including stillbirth, FGR, and subsequent postnatal consequences. The core of this review is the question of whether BW:PW ratio is truly indicative of altered placental efficiency, and whether changes in BW:PW ratio reflect those placentas which adapt their nutrient transfer according to their size. We consider this question using data from mice and humans, focusing upon studies that have measured the activity of the well characterized placental system A amino acid transporter, both in uncomplicated pregnancies and in FGR. Evidence suggests that BW:PW ratio is reduced both in FGR and in pregnancies resulting in a small for gestational age (SGA, birthweight < 10th centile) infant but this effect is more pronounced earlier in gestation (<28 weeks). In mice, there is a clear association between increased BW:PW ratio and increased placental system A activity. Additionally, there is good evidence in wild-type mice that small placentas upregulate placental nutrient transfer to prevent fetal undergrowth. In humans, this association between BW:PW ratio and placental system A

Sex ratios at birth after induced abortion.

PubMed

Urquia, Marcelo L; Moineddin, Rahim; Jha, Prabhat; O'Campo, Patricia J; McKenzie, Kwame; Glazier, Richard H; Henry, David A; Ray, Joel G

2016-06-14

Skewed male:female ratios at birth have been observed among certain immigrant groups. Data on abortion practices that might help to explain these findings are lacking. We examined 1 220 933 births to women with up to 3 consecutive singleton live births between 1993 and 2012 in Ontario. Records of live births, and induced and spontaneous abortions were linked to Canadian immigration records. We determined associations of male:female infant ratios with maternal birthplace, sex of the previous living sibling(s) and prior spontaneous or induced abortions. Male:female infant ratios did not appreciably depart from the normal range among Canadian-born women and most women born outside of Canada, irrespective of the sex of previous children or the characteristics of prior abortions. However, among infants of women who immigrated from India and had previously given birth to 2 girls, the overall male:female ratio was 1.96 (95% confidence interval [CI] 1.75-2.21) for the third live birth. The male:female infant ratio after 2 girls was 1.77 (95% CI 1.26-2.47) times higher if the current birth was preceded by 1 induced abortion, 2.38 (95% CI 1.44-3.94) times higher if preceded by 2 or more induced abortions and 3.88 (95% CI 2.02-7.50) times higher if the induced abortion was performed at 15 weeks or more gestation relative to no preceding abortion. Spontaneous abortions were not associated with male-biased sex ratios in subsequent births. High male:female ratios observed among infants born to women who immigrated from India are associated with induced abortions, especially in the second trimester of pregnancy. © 2016 Canadian Medical Association or its licensors.

Sex ratios at birth after induced abortion

PubMed Central

Urquia, Marcelo L.; Moineddin, Rahim; Jha, Prabhat; O’Campo, Patricia J.; McKenzie, Kwame; Glazier, Richard H.; Henry, David A.; Ray, Joel G.

2016-01-01

Background: Skewed male:female ratios at birth have been observed among certain immigrant groups. Data on abortion practices that might help to explain these findings are lacking. Methods: We examined 1 220 933 births to women with up to 3 consecutive singleton live births between 1993 and 2012 in Ontario. Records of live births, and induced and spontaneous abortions were linked to Canadian immigration records. We determined associations of male:female infant ratios with maternal birthplace, sex of the previous living sibling(s) and prior spontaneous or induced abortions. Results: Male:female infant ratios did not appreciably depart from the normal range among Canadian-born women and most women born outside of Canada, irrespective of the sex of previous children or the characteristics of prior abortions. However, among infants of women who immigrated from India and had previously given birth to 2 girls, the overall male:female ratio was 1.96 (95% confidence interval [CI] 1.75–2.21) for the third live birth. The male:female infant ratio after 2 girls was 1.77 (95% CI 1.26–2.47) times higher if the current birth was preceded by 1 induced abortion, 2.38 (95% CI 1.44–3.94) times higher if preceded by 2 or more induced abortions and 3.88 (95% CI 2.02–7.50) times higher if the induced abortion was performed at 15 weeks or more gestation relative to no preceding abortion. Spontaneous abortions were not associated with male-biased sex ratios in subsequent births. Interpretation: High male:female ratios observed among infants born to women who immigrated from India are associated with induced abortions, especially in the second trimester of pregnancy. PMID:27067818

Integrated photonic power divider with arbitrary power ratios.

PubMed

Xu, Ke; Liu, Lu; Wen, Xiang; Sun, Wenzhao; Zhang, Nan; Yi, Ningbo; Sun, Shang; Xiao, Shumin; Song, Qinghai

2017-02-15

Integrated optical power splitters are one of the fundamental building blocks in photonic integrated circuits. Conventional multimode interferometer-based power splitters are widely used as they have reasonable footprints and are easy to fabricate. However, it is challenging to realize arbitrary split ratios, especially for multi-outputs. In this Letter, an ultra-compact power splitter with a QR code-like nanostructure is designed by a nonlinear fast search method. The highly functional structure is composed of a number of freely designed square pixels with the size of 120×120  nm which could be either dielectric or air. The light waves are scattered by a number of etched squares with optimized locations, and the scattered waves superimpose at the outputs with the desired power ratio. We demonstrate 1×2 splitters with 1:1, 1:2, and 1:3 split ratios, and a 1×3 splitter with the ratio of 1:2:1. The footprint for all the devices is only 3.6×3.6  μm. Well-controlled split ratios are measured for all the cases. The measured transmission efficiencies of all the splitters are close to 80% over 30 nm wavelength range.

On Graduate Student/Faculty Ratios and Faculty Teaching Loads

ERIC Educational Resources Information Center

Madey, Richard; Schoepfle, G. K.

1975-01-01

Describes a survey of 70 institutions with doctoral programs in physics. The faculty teaching loads involve only one formal course in 30 institutions, 1.5 in 11 institutions, and 2 in 22 institutions. Graduate student/faculty ratios range from 1.3 to 5.4. (Author/MLH)

Epiphytic fruticose lichens as biomonitors for retrospective evaluation of the (134)Cs/(137)Cs ratio in Fukushima fallout.

PubMed

Ramzaev, V; Barkovsky, A; Gromov, A; Ivanov, S; Kaduka, M

2014-12-01

In 2011-2013, sampling of epiphytic fruticose lichens of the genera Usnea, Bryoria and Alectoria was carried out on Sakhalin and Kuril Islands (the Sakhalin region, Russia) to investigate contamination of these organisms with the Fukushima-derived (134)Cs and (137)Cs. Activities of the radionuclides were determined in all 56 samples of lichens taken for the analysis. After correction for radioactive decay (on 15 March 2011), the activity concentrations ranged from 2.1 Bq kg(-1) (d.w.) to 52 Bq kg(-1) for (134)Cs and from 2.3 Bq kg(-1) to 52 Bq kg(-1) for (137)Cs. Cesium-134 and (137)Cs activities for the whole set of lichens (n = 56) were strongly positively correlated; Spearman's rank correlation coefficient was calculated as 0.991 (P < 0.01). The activity concentrations of (134)Cs and (137)Cs in Usnea lichens from the Sakhalin and Kunashir islands declined with a factor of three in the period from 2011 to 2013. The average biological half-time for both cesium radionuclides in lichens of the genus Usnea is estimated as 1.3 y. The mean of 0.99 ± 0.10 and median of 0.99 were calculated for the decay corrected (134)Cs/(137)Cs activities ratios in the lichens (n = 56). The radionuclides ratio in the lichens did not depend on location of sampling site, species and the time that had passed after the Fukushima accident. The regression analysis has shown the background pre-Fukushima level of (137)Cs of 0.4 ± 0.3 Bq kg(-1), whereas the ratio between the Fukushima-borne (134)Cs and (137)Cs in the lichens was estimated as 1.04. The (134)Cs/(137)Cs activities ratio in lichens from the Sakhalin region is consistent with the ratios reported by others for the heavy contaminated areas on Honshu Island in Japan following the Fukushima accident. The activity concentrations of natural (7)Be in lichens from the Sakhalin region varied between 100 Bq kg(-1) and 600 Bq kg(-1); the activity concentrations did not exhibit temporal variations during a 2y

Non-linear properties of metallic cellular materials with a negative Poisson's ratio

NASA Technical Reports Server (NTRS)

Choi, J. B.; Lakes, R. S.

1992-01-01

Negative Poisson's ratio copper foam was prepared and characterized experimentally. The transformation into re-entrant foam was accomplished by applying sequential permanent compressions above the yield point to achieve a triaxial compression. The Poisson's ratio of the re-entrant foam depended on strain and attained a relative minimum at strains near zero. Poisson's ratio as small as -0.8 was achieved. The strain dependence of properties occurred over a narrower range of strain than in the polymer foams studied earlier. Annealing of the foam resulted in a slightly greater magnitude of negative Poisson's ratio and greater toughness at the expense of a decrease in the Young's modulus.

Concurrent validity and interrater reliability of a new smartphone application to assess 3D active cervical range of motion in patients with neck pain.

PubMed

Stenneberg, Martijn S; Busstra, Harm; Eskes, Michel; van Trijffel, Emiel; Cattrysse, Erik; Scholten-Peeters, Gwendolijne G M; de Bie, Rob A

2018-04-01

There is a lack of valid, reliable, and feasible instruments for measuring planar active cervical range of motion (aCROM) and associated 3D coupling motions in patients with neck pain. Smartphones have advanced sensors and appear to be suitable for these measurements. To estimate the concurrent validity and interrater reliability of a new iPhone application for assessing planar aCROM and associated 3D coupling motions in patients with neck pain, using an electromagnetic tracking device as a reference test. Cross-sectional study. Two samples of neck pain patients were recruited; 30 patients for the validity study and 26 patients for the reliability study. Validity was estimated using intraclass correlation coefficients (ICCs), and by calculating 95% limits of agreement (LoA). To estimate interrater reliability, ICCs were calculated. Cervical 3D coupling motions were analyzed by calculating the cross-correlation coefficients and ratio between the main motions and coupled motions for both instruments. ICCs for concurrent validity and interrater reliability ranged from 0.90 to 0.99. The width of the 95% LoA ranged from about 5° for right lateral bending to 11° for total rotation. No significant differences were found between both devices for associated coupling motion analysis. The iPhone application appears to be a useful discriminative tool for the measurement of planar aCROM and associated coupling motions in patients with neck pain. It fulfills the need for a valid, reliable, and feasible instrument in clinical practice and research. Therapists and researchers should consider measurement error when interpreting scores. Copyright © 2017 Elsevier Ltd. All rights reserved.

Range Measurement as Practiced in the Deep Space Network

NASA Technical Reports Server (NTRS)

Berner, Jeff B.; Bryant, Scott H.; Kinman, Peter W.

2007-01-01

Range measurements are used to improve the trajectory models of spacecraft tracked by the Deep Space Network. The unique challenge of deep-space ranging is that the two-way delay is long, typically many minutes, and the signal-to-noise ratio is small. Accurate measurements are made under these circumstances by means of long correlations that incorporate Doppler rate-aiding. This processing is done with commercial digital signal processors, providing a flexibility in signal design that can accommodate both the traditional sequential ranging signal and pseudonoise range codes. Accurate range determination requires the calibration of the delay within the tracking station. Measurements with a standard deviation of 1 m have been made.

Multigenerational response to artificial selection for biased clutch sex ratios in Tigriopus californicus populations.

PubMed

Alexander, H J; Richardson, J M L; Anholt, B R

2014-09-01

Polygenic sex determination (PSD) is relatively rare and theoretically evolutionary unstable, yet has been reported across a range of taxa. Evidence for multilocus PSD is provided by (i) large between-family variance in sex ratio, (ii) paternal and maternal effects on family sex ratio and (iii) response to selection for family sex ratio. This study tests the polygenic hypothesis of sex determination in the harpacticoid copepod Tigriopus californicus using the criterion of response to selection. We report the first multigenerational quantitative evidence that clutch sex ratio responds to artificial selection in both directions (selection for male- and female-biased families) and in multiple populations of T. californicus. In the five of six lines that showed a response to selection, realized heritability estimated by multigenerational analysis ranged from 0.24 to 0.58. Divergence of clutch sex ratio between selection lines is rapid, with response to selection detectable within the first four generations of selection. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Influence of accommodative lag upon the far-gradient measurement of accommodative convergence to accommodation ratio in strabismic patients.

PubMed

Miyata, Manabu; Hasebe, Satoshi; Ohtsuki, Hiroshi

2006-01-01

To determine the influence of the lag of accommodation (LOA) on the accommodative convergence to accommodation (AC/A) ratio measured by the far-gradient method in strabismic patients. The AC/A ratio was measured with a distance target viewed with and without -3.00 diopter (D) addition lenses in 63 patients with different types of strabismus (age range, 7-34 years; range of strabismic angle, -60 to +40 prism diopters; refractive error range, -7.33 to +6.63 D). The LOA for the same lens was measured with an open-view-type autorefractometer. The stimulus AC/A ratio and the AC/A ratio adjusted by the individually measured LOA (adjusted AC/A ratio) were compared. The mean +/- SD of the LOA to the -3.00 D lenses was 1.06 +/- 0.43 D. The mean adjusted AC/A ratio was 41% greater than the stimulus AC/A ratio. The LOA differed widely among patients (0.13 to 2.14 D), and a large LOA tended to appear in myopic or young patients. The AC/A ratio obtained using the conventional far-gradient method is significantly biased by the LOA, and thus does not always represent the actual relationship between accommodation and vergence control systems. Copyright Japanese Ophthalmological Society 2006.

Explorations in Statistics: The Analysis of Ratios and Normalized Data

ERIC Educational Resources Information Center

Curran-Everett, Douglas

2013-01-01

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This ninth installment of "Explorations in Statistics" explores the analysis of ratios and normalized--or standardized--data. As researchers, we compute a ratio--a numerator divided by a denominator--to compute a…

Identification of a Long-range Protein Network That Modulates Active Site Dynamics in Extremophilic Alcohol Dehydrogenases*

PubMed Central

Nagel, Zachary D.; Cun, Shujian; Klinman, Judith P.

2013-01-01

A tetrameric thermophilic alcohol dehydrogenase from Bacillus stearothermophilus (ht-ADH) has been mutated at an aromatic side chain in the active site (Trp-87). The ht-W87A mutation results in a loss of the Arrhenius break seen at 30 °C for the wild-type enzyme and an increase in cold lability that is attributed to destabilization of the active tetrameric form. Kinetic isotope effects (KIEs) are nearly temperature-independent over the experimental temperature range, and similar in magnitude to those measured above 30 °C for the wild-type enzyme. This suggests that the rigidification in the wild-type enzyme below 30 °C does not occur for ht-W87A. A mutation at the dimer-dimer interface in a thermolabile psychrophilic homologue of ht-ADH, ps-A25Y, leads to a more thermostable enzyme and a change in the rate-determining step at low temperature. The reciprocal mutation in ht-ADH, ht-Y25A, results in kinetic behavior similar to that of W87A. Collectively, the results indicate that flexibility at the active site is intimately connected to a subunit interaction 20 Å away. The convex Arrhenius curves previously reported for ht-ADH (Kohen, A., Cannio, R., Bartolucci, S., and Klinman, J. P. (1999) Nature 399, 496–499) are proposed to arise, at least in part, from a change in subunit interactions that rigidifies the substrate-binding domain below 30 °C, and impedes the ability of the enzyme to sample the catalytically relevant conformational landscape. These results implicate an evolutionarily conserved, long-range network of dynamical communication that controls C-H activation in the prokaryotic alcohol dehydrogenases. PMID:23525111

Neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in mood disorders: A meta-analysis.

PubMed

Mazza, Mario Gennaro; Lucchi, Sara; Tringali, Agnese Grazia Maria; Rossetti, Aurora; Botti, Eugenia Rossana; Clerici, Massimo

2018-06-08

The immune and inflammatory system is involved in the etiology of mood disorders. Neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and monocyte/lymphocyte ratio (MLR) are inexpensive and reproducible biomarkers of inflammation. This is the first meta-analysis exploring the role of NLR and PLR in mood disorder. We identified 11 studies according to our inclusion criteria from the main Electronic Databases. Meta-analyses were carried out generating pooled standardized mean differences (SMDs) between index and healthy controls (HC). Heterogeneity was estimated. Relevant sensitivity and meta-regression analyses were conducted. Subjects with bipolar disorder (BD) had higher NLR and PLR as compared with HC (respectively SMD = 0.672; p < 0.001; I 2  = 82.4% and SMD = 0.425; p = 0.048; I 2  = 86.53%). Heterogeneity-based sensitivity analyses confirmed these findings. Subgroup analysis evidenced an influence of bipolar phase on the overall estimate whit studies including subjects in manic and any bipolar phase showing a significantly higher NLR and PLR as compared with HC whereas the effect was not significant among studies including only euthymic bipolar subjects. Meta-regression showed that age and sex influenced the relationship between BD and NLR but not the relationship between BD and PLR. Meta-analysis was not carried out for MLR because our search identified only one study when comparing BD to HC, and only one study when comparing MDD to HC. Subjects with major depressive disorder (MDD) had higher NLR as compared with HC (SMD = 0.670; p = 0.028; I 2  = 89.931%). Heterogeneity-based sensitivity analyses and meta-regression confirmed these findings. Our meta-analysis supports the hypothesis that an inflammatory activation occurs in mood disorders and NLR and PLR may be useful to detect this activation. More researches including comparison of NLR, PLR and MLR between different bipolar phases and between BD and MDD

Tonopah Test Range Post-Closure Inspection Annual Report, Tonopah Test Range, Nevada, Calendar Year 2003

DOE Office of Scientific and Technical Information (OSTI.GOV)

U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Bechtel Nevada

This post-closure inspection report provides documentation of the semiannual inspection activities, maintenance and repair activities, and conclusions and recommendations for calendar year 2003 for eight corrective action units located on the Tonopah Test Range, Nevada.

Bird species migration ratio in East Asia, Australia, and surrounding islands.

PubMed

Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

2013-08-01

Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

Bird species migration ratio in East Asia, Australia, and surrounding islands

NASA Astrophysics Data System (ADS)

Kuo, Yiliang; Lin, Da-Li; Chuang, Fu-Man; Lee, Pei-Fen; Ding, Tzung-Su

2013-08-01

Bird migration and its relationship with the contemporary environment have attracted long-term discussion. We calculated the avian migration ratio (the proportion of breeding species that migrate) in the areas from 70°E to 180°E and examined its relationship with the annual ranges of ambient temperature, primary productivity (estimated by the Enhanced Vegetation Index), and precipitation, along with island isolation and elevational range. The avian migration ratio increased with increasing latitude in general but varied greatly between the two hemispheres. Additionally, it showed minimal differences between continents and islands. Our analyses revealed that the seasonality of ambient temperature, which represents the energy expenditure of birds, is the dominant factor in determining bird species migration. Seasonality in primary productivity and other environmental factors play an indirect or limited role in bird species migration. The lower avian migration ratio in the Southern Hemisphere can be attributed to its paleogeographical isolation, stable paleoclimate, and warm contemporary environment. Under current trends of global warming, our findings should lead to further studies of the impact of warming on bird migration.

Problems encountered when defining Arctic amplification as a ratio.

PubMed

Hind, Alistair; Zhang, Qiong; Brattström, Gudrun

2016-07-27

In climate change science the term 'Arctic amplification' has become synonymous with an estimation of the ratio of a change in Arctic temperatures compared with a broader reference change under the same period, usually in global temperatures. Here, it is shown that this definition of Arctic amplification comes with a suite of difficulties related to the statistical properties of the ratio estimator itself. Most problematic is the complexity of categorizing uncertainty in Arctic amplification when the global, or reference, change in temperature is close to 0 over a period of interest, in which case it may be impossible to set bounds on this uncertainty. An important conceptual distinction is made between the 'Ratio of Means' and 'Mean Ratio' approaches to defining a ratio estimate of Arctic amplification, as they do not only possess different uncertainty properties regarding the amplification factor, but are also demonstrated to ask different scientific questions. Uncertainty in the estimated range of the Arctic amplification factor using the latest global climate models and climate forcing scenarios is expanded upon and shown to be greater than previously demonstrated for future climate projections, particularly using forcing scenarios with lower concentrations of greenhouse gases.

Radial fingering under arbitrary viscosity and density ratios

NASA Astrophysics Data System (ADS)

Anjos, Pedro H. A.; Dias, Eduardo O.; Miranda, José A.

2017-08-01

We study viscous fingering formation in radial Hele-Shaw cell geometry considering the combined action of capillary and inertial effects for arbitrary values of viscosity and density ratios. We tackle the problem by employing a perturbative mode-coupling approach and focus our attention on weakly nonlinear stages of the dynamics. If inertial effects are neglected, our theoretical results indicate that the shape of the resulting interfacial patterns is significantly affected by changes in the viscosity ratio. Under such conditions, the growing fingers tend to proliferate through a repeated ramification process (e.g., by finger bifurcation, quadrifurcation, etc.) as the capillary number is increased. Nevertheless, we find that this scenario is dramatically altered when inertia is taken into account. When inertia is relevant, the conventional finger splitting morphologies are replaced by three-lobed structures, characterized by the occurrence of sidebranching phenomena. We verify that slightly different types of sidebranched patterns arise, presenting either wide or sharp fingertips, for a range of capillary numbers and density ratios.

Isolation and Characterization of Precise Dye/Dendrimer Ratios

PubMed Central

Dougherty, Casey A.; Furgal, Joseph C.; van Dongen, Mallory A.; Goodson, Theodore; Banaszak Holl, Mark M.; Manono, Janet; DiMaggio, Stassi

2014-01-01

Fluorescent dyes are commonly conjugated to nanomaterials for imaging applications using stochastic synthesis conditions that result in a Poisson distribution of dye/particle ratios and therefore a broad range of photophysical and biodistribution properties. We report the isolation and characterization of generation 5 poly(amidoamine) (G5 PAMAM) dendrimer samples containing 1, 2, 3, and 4 fluorescein (FC) or 6-carboxytetramethylrhodamine succinimidyl ester (TAMRA) dyes per polymer particle. For the fluorescein case, this was achieved by stochastically functionalizing dendrimer with a cyclooctyne `click' ligand, separation into sample containing precisely defined `click' ligand/particle ratios using reverse-phase high performance liquid chromatography (rp-HPLC), followed by reaction with excess azide-functionalized fluorescein dye. For the TAMRA samples, stochastically functionalized dendrimer was directly separated into precise dye/particle ratios using rp-HPLC. These materials were characterized using 1H and 19F NMR, rp-HPLC, UV-Vis and fluorescence spectroscopy, lifetime measurements, and MALDI. PMID:24604830

CD4/CD8 Ratio and KT Ratio Predict Yellow Fever Vaccine Immunogenicity in HIV-Infected Patients

PubMed Central

Hunt, Peter W.; Huang, Yong; Simoes, Marisol; Lima, Sheila B.; Freire, Marcos S.; Caiaffa-Filho, Helio H.; Hong, Marisa A.; Costa, Dayane Alves; Dias, Juliana Zanatta C.; Cerqueira, Natalia B.; Nishiya, Anna Shoko; Sabino, Ester Cerdeira; Sartori, Ana M.; Kallas, Esper G.

2016-01-01

Background HIV-infected individuals have deficient responses to Yellow Fever vaccine (YFV) and may be at higher risk for adverse events (AE). Chronic immune activation–characterized by low CD4/CD8 ratio or high indoleamine 2,3-dioxygenase-1 (IDO) activity—may influence vaccine response in this population. Methods We prospectively assessed AE, viremia by the YFV virus and YF-specific neutralizing antibodies (NAb) in HIV-infected (CD4>350) and -uninfected adults through 1 year after vaccination. The effect of HIV status on initial antibody response to YFV was measured during the first 3 months following vaccination, while the effect on persistence of antibody response was measured one year following vaccination. We explored CD4/CD8 ratio, IDO activity (plasma kynurenine/tryptophan [KT] ratio) and viremia by Human Pegivirus as potential predictors of NAb response to YFV among HIV-infected participants with linear mixed models. Results 12 HIV-infected and 45-uninfected participants were included in the final analysis. HIV was not significantly associated with AE, YFV viremia or NAb titers through the first 3 months following vaccination. However, HIV–infected participants had 0.32 times the NAb titers observed for HIV-uninfected participants at 1 year following YFV (95% CI 0.13 to 0.83, p = 0.021), independent of sex, age and prior vaccination. In HIV-infected participants, each 10% increase in CD4/CD8 ratio predicted a mean 21% higher post-baseline YFV Nab titer (p = 0.024). Similarly, each 10% increase in KT ratio predicted a mean 21% lower post-baseline YFV Nab titer (p = 0.009). Viremia by Human Pegivirus was not significantly associated with NAb titers. Conclusions HIV infection appears to decrease the durability of NAb responses to YFV, an effect that may be predicted by lower CD4/CD8 ratio or higher KT ratio. PMID:27941965

Isotopic ratios of 36Cl/Cl in Japanese surface soil

NASA Astrophysics Data System (ADS)

Seki, R.; Matsuhiro, T.; Nagashima, Y.; Takahashi, T.; Sasa, K.; Sueki, K.; Tosaki, Y.; Bessho, K.; Matsumura, H.; Miura, T.

2007-06-01

We have measured the 36Cl/Cl ratio of uncultivated surface soil samples collected from 11 areas distributed throughout Japan to determine the undisturbed value of the ratio. The ratio was found to be on the order of 10-13 except for the Tokai-mura area, where four research reactors, two commercial nuclear power plants and a nuclear fuel reprocessing plant have been operated. The observed ratio in the Tokai-mura area was higher than 10-12. Notably, soil samples collected from a site of commercial BWR nuclear power plants in Fukushima prefecture showed no significant increase in 36Cl/Cl ratio. The 36Cl/Cl ratio depth profiles of soil samples collected at both of Makabe-town and Tokai-mura were also measured. Since Makabe-town is located about 50 km apart from Tokai-mura, we do not expect it to be affected by the nuclear facilities. No large variations were observed in the Makabe depth profile; the measured ratios ranged from ∼3 to ∼5 × 10-13. The result obtained for Tokai-mura is significantly different in that from the surface to about 80 cm depth, the measured ratios, ∼10-12, are much higher than any at Makabe. At depth below 80 cm, the Tokai-mura ratios are lower and become indistinguishable from those at Makabe. The 36Cl/Cl ratio in unaffected areas of Japan is estimated to be 3-4 × 10-13.

Biological N2 fixation mainly controlled by Sphagnum tissue N:P ratio in ombrotrophic bogs

NASA Astrophysics Data System (ADS)

Zivkovic, Tatjana; Moore, Tim R.

2017-04-01

-fixation across a range of bogs, eight study sites along the latitudinal gradient from temperate, boreal to subarctic zone in eastern Canada were selected. From each bog, two predominant microptopographies, hummocks and hollows, were tested for both N2-fixation activity in the laboratory and Sphagnum tissue concentrations of N, P and N:P ratio. We found that 65% of the variance in the increase of N2-fixation activity was explained by the decrease in N:P ratio in hollows (n = 73) but only about 20% in hummocks (n = 78). Changes in neither N or P concentration alone explained the increase in N2-fixation better than N:P ratio. We interpret that the difference between hollows and hummocks results from the availability of moisture that further limits N2-fixation. When moisture is not a limiting factor, i.e. in hollows, N:P ratio will be the best predictor of N2-fixation in bogs. Both studies suggest that the relative P availability to Sphagnum-associated diazotrophs, measured as a tissue N:P ratio, best describes N2-fixation activity in bogs, especially ones exposed to larger N deposition.

Ratio Tables to Promote Proportional Reasonings in the Primary Classroom

ERIC Educational Resources Information Center

Dole, Shelley

2008-01-01

There are many classroom activities that can be implemented with primary students that introduce and immerse them in ratio investigations. Some enjoyable tasks include finding the ratio of tongue rollers to non-tongue rollers in the classroom; left-hand dominant to right-hand dominant; right-thumb over left-thumb when clasping the hands to…

Stress Ratio Effects on Small Fatigue Crack Growth in Ti-6Al-4V (Preprint)

DTIC Science & Technology

2008-11-01

crack effect is observed in this alloy , consistent with previous observations, where small cracks grew at stress intensity factor ranges below the long...high stress intensity factor ranges, ΔK, on the order of 10 MPa√m or greater. A significant small crack effect is observed in this alloy , consistent...the behavior of small cracks under different stress ratios in Ti-6Al-4V, an alloy commonly used for fan airfoils. The effect of stress ratio on

Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy.

PubMed

Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; Sam Ma, Zhanshan

2016-12-23

There are three sex ratio strategies (SRS) in nature-male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton's local mate competition (LMC) and Clark's local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC &LRC) in the field of SRS research.

Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy

NASA Astrophysics Data System (ADS)

Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; (Sam) Ma, Zhanshan

2016-12-01

There are three sex ratio strategies (SRS) in nature—male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton’s local mate competition (LMC) and Clark’s local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC & LRC) in the field of SRS research.

Method and apparatus for instantaneous band ratioing in a reflectance radiometer

NASA Technical Reports Server (NTRS)

Goetz, Alexander F. H. (Inventor); Machida, Richard A. (Inventor)

1982-01-01

A hand-held instrument is provided to compare information from selected infrared and visible bands in the 0.4 to 2.5 micrometer range, to perform ratioing via a dividing circuit (17) and to directly read out, via a display system (18), ratio values in a continuous digital display. The dual-beam, ratioing radiometer contains two optical trains (10, 12), each having two repeater lenses (L1a, L1b and L2a, L2b) and a cooled lead sulfide detector (D1, D2). One of the trains (10) is pivotal to facilitate measurements at distances ranging from about 1 meter to infinity. The optical trains are intersected by a set of two coaxially-mounted filter wheels (F1, F2), each containing up to five interference filters and slits to pass radiation filtered by the other. Filters with band passes as narrow as 0.01 micrometer are used in the region 0.4 to 2.5 micrometers. The total time for a calibration and measurement is only a few seconds. It is known from previous field studies using prior art devices, that materials, e.g., clay minerals, and carbonate minerals such as limestone, have unique spectral properties in the 2.0 to 2.5 micrometer region. Using properly chosen spectral filters, and ratioing the signals to remove the effect of topography on the brightness measured, the instrument can be used for real-time analysis of reflecting materials in the field. Other materials in the broader range of 0.4 to 2.5 micrometers (and even beyond) could be similarly identified once the reflectance spectrum of the material is established by any means.

Electron-density-sensitive Line Ratios of Fe XIII– XVI from Laboratory Sources Compared to CHIANTI

NASA Astrophysics Data System (ADS)

Weller, M. E.; Beiersdorfer, P.; Soukhanovskii, V. A.; Scotti, F.; LeBlanc, B. P.

2018-02-01

We present electron-density-sensitive line ratios for Fe XIII– XVI measured in the spectral wavelength range of 200–440 Å and an electron density range of (1–4) × 1013 cm‑3. The results provide a test at the high-density limit of density-sensitive line ratios useful for astrophysical studies. The measurements were performed on the National Spherical Torus Experiment-Upgrade, where electron densities were measured independently by the laser Thomson scattering diagnostic. Spectra were collected with a flat-field grazing-incidence spectrometer, which provided a spectral resolution of up to 0.3 Å, i.e., high resolution across the broad wavelength range. The response of the instrument was relatively calibrated using spectroscopic techniques in order to improve accuracy. The line ratios are compared to other laboratory sources and the latest version of CHIANTI (8.0.2), and an agreement within 30% is found.

Solar-diffuser panel and ratioing radiometer approach to satellite sensor on-board calibration

NASA Technical Reports Server (NTRS)

Slater, Philip N.; Palmer, James M.

1991-01-01

The use of a solar-diffuser panel is a desirable approach to the on-board absolute radiometric calibration of satellite multispectral sensors used for earth observation in the solar reflective spectral range. It provides a full aperture, full field, end-to-end calibration near the top of the sensor's dynamic range and across its entire spectral response range. A serious drawback is that the panel's reflectance, and the response of any simple detector used to monitor its reflectance may change with time. This paper briefly reviews some preflight and on-board methods for absolute calibration and introduces the ratioing-radiometer concept in which the radiance of the panel is ratioed with respect to the solar irradiance at the time the multispectral sensor is viewing the panel in its calibration mode.

Is Log Ratio a Good Value for Measuring Return in Stock Investments?

NASA Astrophysics Data System (ADS)

Ultsch, Alfred

Measuring the rate of return is an important issue for theory and practice of investments in the stock market. A common measure for rate of return is the logarithm of the ratio of successive prices (LogRatio). In this paper it is shown that LogRatio as well as arithmetic return rate (Ratio) have several disadvantages. As an alternative relative differences (RelDiff) are proposed to measure return. The stability against numerical and rounding errors of RelDiff is much better than for LogRatios and Ratio). RelDiff values are identical to LogRatios and Return for small absolutes. The usage of RelDiff maps returns to a finite range. For most subsequent analyses this is a big advantage. The usefulness of the approach is demonstrated on daily return rates of a large set of actual stocks. It is shown that returns can be modeled with a very simple mixture of distributions in great precision using Relative differences.

Fabrication of organic solar cells with design blend P3HT: PCBM variation of mass ratio

NASA Astrophysics Data System (ADS)

Supriyanto, Agus; Mustaqim, Amrina; Agustin, Maya; Ramelan, Ari H.; Suyitno; Septa Rosa, Erlyta; Yofentina; Nurosyid, Fahru

2016-02-01

Organic solar cells of FTO/PEDOT: PSS/P3HT: PCBM/Al has been fabricated, and its performance has been tested in dark and under various illumination of light intensity 1000 W/m2. The active materials used in this study are poly (3- hexylthiophene) (P3HT) and [6, 6]-phenyl-C61-butyric acid methyl ester (PCBM). P3HT is the donor while PCBM acts as an acceptor. Variation of PCBM and P3HT are 1:1, 1:2, 1:3, 1:4 and 1:5. P3HT: PCBM was mixed by chlorobenzene solvents. The mixing was done by using the ultrasonic cleaner. The absorbance characterization using by UV-Visible Spectrometer Lambda 25 instrument and I-V characterization has been tested using a set of 2602A Keithley instrument. Absorbance characterization shows that two peaks are formed. The first peak in the range of 300 to 350 nm which is a range of PCBM and the second peak range from 450 to 600 nm which is a range of P3HT. As the mass ratio increases, the second peak of P3HT increases while the first peak does not change. The gap energy estimated by the Tauc method is 2.0 eV. I-V characterization of the efficiency was obtained. The efficiency of sample 1, 2, 3, 4, and 5 are 5.80x10-2%; 6.46x10-2%; 7.72x10-2%; 8.25x10-2% and 9.81x10-2%, respectively. The highest value of efficiency was obtained at mass ratio 1:5.

A More Stringent Constraint on the Mass Ratio of Binary Neutron Star Merger GW170817

NASA Astrophysics Data System (ADS)

Gao, He; Cao, Zhoujian; Ai, Shunke; Zhang, Bing

2017-12-01

Recently, the LIGO–Virgo Collaborations reported their first detection of gravitational-wave (GW) signals from the low-mass compact binary merger GW170817, which is most likely due to a double neutron star (NS) merger. With the GW signals only, the chirp mass of the binary is precisely constrained to {1.188}-0.002+0.004 {M}ȯ , but the mass ratio is loosely constrained in the range 0.4–1, so that a very rough estimation of the individual NS masses (1.36 M ⊙ < M 1 < 2.26 M ⊙ and 0.86 M ⊙ < M 2 < 1.36 M ⊙) was obtained. Here, we propose that if one can constrain the dynamical ejecta mass through performing kilonova modeling of the optical/IR data, by utilizing an empirical relation between the dynamical ejecta mass and the mass ratio of NS binaries, one may place a more stringent constraint on the mass ratio of the system. For instance, considering that the red “kilonova” component is powered by the dynamical ejecta, we reach a tight constraint on the mass ratio in the range of 0.46–0.59. Alternatively, if the blue “kilonova” component is powered by the dynamical ejecta, the mass ratio would be constrained in the range of 0.53–0.67. Overall, such a multi-messenger approach could narrow down the mass ratio of GW170817 system to the range of 0.46–0.67, which gives a more precise estimation of the individual NS mass than pure GW signal analysis, i.e., 1.61 M ⊙ < M 1 < 2.11 M ⊙ and 0.90 M ⊙ < M 2 < 1.16 M ⊙.

Determination of electron temperature in a penning discharge by the helium line ratio method

NASA Technical Reports Server (NTRS)

Richardson, R. W.

1975-01-01

The helium line ratio technique was used to determine electron temperatures in a toroidal steady-state Penning discharge operating in helium. Due to the low background pressure, less than .0001 torr, and the low electron density, the corona model is expected to provide a good description of the excitation processes in this discharge. In addition, by varying the Penning discharge anode voltage and background pressure, it is possible to vary the electron temperature as measured by the line ratio technique over a wide range (10 to 100+ eV). These discharge characteristics allow a detailed comparison of electron temperatures measured from different possible line ratios over a wide range of temperatures and under reproducible steady-state conditions. Good agreement is found between temperatures determined from different neutral line ratios, but use of the helium ion line results in a temperature systematically 10 eV high compared to that from the neutral lines.

Effect of various Na/K ratios in low-salinity well water on growth performance and physiological response of Pacific white shrimp Litopenaeus vannamei

NASA Astrophysics Data System (ADS)

Liu, Hongyu; Tan, Beiping; Yang, Jinfang; Lin, Yingbo; Chi, Shuyan; Dong, Xiaohui; Yang, Qihui

2014-09-01

To investigate the influence of sodium to potassium (Na/K) ratios on the growth performance and physiological response of the Pacific white shrimp ( Litopenaeus vananmei), various concentrations of KCl were added to low-salinity well water (salinity 4) in an 8-week culture trial. Six treatments with Na/K ratios of 60:1, 42:1, 33:1, 23:1, 17:1, and 14:1 were replicated in triplicate. The highest weight-gain rate (3 506±48)% and survival rate (89.38±0.88)% was observed in well water with Na/K ratios of 23:1 and 42:1, respectively, while the feed conversion ratio (1.02±0.01), oxygen consumption, and ammonia-N excretion rate was the lowest in the medium with a Na/K ratio of 23:1. Gill Na+-K+-ATPase activity, as an indicator of osmoregulation, peaked in the treatment where the Na/K ratio was 17:1. The total hemocyte count, respiratory burst, and immune-related enzyme activities (ALP, LSZ, PO, and SOD) of L. vananmei were affected significantly by Na/K ratios ( P<0.05). After challenged with Vibrio harveyi, the cumulative mortality of shrimp reared in a Na/K ratio of 23:1 (30±14.14)% was significantly lower than the control (75±7.07)%. In conclusion, the addition of K+ to low-salinity well water in L. vannamei cultures is feasible. Na/K ratios ranging from 23:1 to 33:1 might improve survival and growth. Immunity and disease resistance are also closely related to the Na/K ratio of the low-salinity well water. The findings may contribute to the development of more efficient K + remediation strategies for L. vananmei culture in low-salinity well water.

Fine-scale assessment of home ranges and activity patterns for resident black vultures (Coragyps atratus) and turkey vultures (Cathartes aura)

DOE PAGES

Holland, Amanda E.; Byrne, Michael E.; Bryan, A. Lawrence; ...

2017-07-05

Knowledge of black vulture (Coragyps atratus) and turkey vulture (Cathartes aura) spatial ecology is surprisingly limited despite their vital ecological roles. Fine-scale assessments of space use patterns and resource selection are particularly lacking, although development of tracking technologies has allowed data collection at finer temporal and spatial resolution. The objectives of this study were to conduct the first assessment of monthly home range and core area sizes of resident black and turkey vultures with consideration to sex, as well as elucidate differences in monthly, seasonal, and annual activity patterns based on fine-scale movement data analyses. We collected 2.8-million locations formore » 9 black and 9 turkey vultures from June 2013 –August 2015 using solar-powered GSM/GPS transmitters. We quantified home ranges and core areas using the dynamic Brownian bridge movement model and evaluated differences as a function of species, sex, and month. Mean monthly home ranges for turkey vultures were ~50% larger than those of black vultures, although mean core area sizes did not differ between species. Turkey vulture home ranges varied little across months, with exception to a notable reduction in space-use in May, which corresponds with timing of chick-rearing activities. Black vulture home ranges and core areas as well as turkey vulture core areas were larger in breeding season months (January–April). Comparison of space use between male and female vultures was only possible for black vultures, and space use was only slightly larger for females during breeding months (February–May). Analysis of activity patterns revealed turkey vultures spend more time in flight and switch motion states (between flight and stationary) more frequently than black vultures across temporal scales. Our study reveals substantive variability in space use and activity rates between sympatric black and turkey vultures, providing insights into potential behavioral

Fine-scale assessment of home ranges and activity patterns for resident black vultures (Coragyps atratus) and turkey vultures (Cathartes aura)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Amanda E.; Byrne, Michael E.; Bryan, A. Lawrence

Knowledge of black vulture (Coragyps atratus) and turkey vulture (Cathartes aura) spatial ecology is surprisingly limited despite their vital ecological roles. Fine-scale assessments of space use patterns and resource selection are particularly lacking, although development of tracking technologies has allowed data collection at finer temporal and spatial resolution. The objectives of this study were to conduct the first assessment of monthly home range and core area sizes of resident black and turkey vultures with consideration to sex, as well as elucidate differences in monthly, seasonal, and annual activity patterns based on fine-scale movement data analyses. We collected 2.8-million locations formore » 9 black and 9 turkey vultures from June 2013 –August 2015 using solar-powered GSM/GPS transmitters. We quantified home ranges and core areas using the dynamic Brownian bridge movement model and evaluated differences as a function of species, sex, and month. Mean monthly home ranges for turkey vultures were ~50% larger than those of black vultures, although mean core area sizes did not differ between species. Turkey vulture home ranges varied little across months, with exception to a notable reduction in space-use in May, which corresponds with timing of chick-rearing activities. Black vulture home ranges and core areas as well as turkey vulture core areas were larger in breeding season months (January–April). Comparison of space use between male and female vultures was only possible for black vultures, and space use was only slightly larger for females during breeding months (February–May). Analysis of activity patterns revealed turkey vultures spend more time in flight and switch motion states (between flight and stationary) more frequently than black vultures across temporal scales. Our study reveals substantive variability in space use and activity rates between sympatric black and turkey vultures, providing insights into potential behavioral

Dense range map reconstruction from a versatile robotic sensor system with an active trinocular vision and a passive binocular vision.

PubMed

Kim, Min Young; Lee, Hyunkee; Cho, Hyungsuck

2008-04-10

One major research issue associated with 3D perception by robotic systems is the creation of efficient sensor systems that can generate dense range maps reliably. A visual sensor system for robotic applications is developed that is inherently equipped with two types of sensor, an active trinocular vision and a passive stereo vision. Unlike in conventional active vision systems that use a large number of images with variations of projected patterns for dense range map acquisition or from conventional passive vision systems that work well on specific environments with sufficient feature information, a cooperative bidirectional sensor fusion method for this visual sensor system enables us to acquire a reliable dense range map using active and passive information simultaneously. The fusion algorithms are composed of two parts, one in which the passive stereo vision helps active vision and the other in which the active trinocular vision helps the passive one. The first part matches the laser patterns in stereo laser images with the help of intensity images; the second part utilizes an information fusion technique using the dynamic programming method in which image regions between laser patterns are matched pixel-by-pixel with help of the fusion results obtained in the first part. To determine how the proposed sensor system and fusion algorithms can work in real applications, the sensor system is implemented on a robotic system, and the proposed algorithms are applied. A series of experimental tests is performed for a variety of configurations of robot and environments. The performance of the sensor system is discussed in detail.

Using effort information with change-in-ratio data for population estimation

USGS Publications Warehouse

Udevitz, Mark S.; Pollock, Kenneth H.

1995-01-01

Most change-in-ratio (CIR) methods for estimating fish and wildlife population sizes have been based only on assumptions about how encounter probabilities vary among population subclasses. When information on sampling effort is available, it is also possible to derive CIR estimators based on assumptions about how encounter probabilities vary over time. This paper presents a generalization of previous CIR models that allows explicit consideration of a range of assumptions about the variation of encounter probabilities among subclasses and over time. Explicit estimators are derived under this model for specific sets of assumptions about the encounter probabilities. Numerical methods are presented for obtaining estimators under the full range of possible assumptions. Likelihood ratio tests for these assumptions are described. Emphasis is on obtaining estimators based on assumptions about variation of encounter probabilities over time.

Performance of single-stage axial-flow transonic compressor with rotor and stator aspect ratios of 1.19 and 1.26 respectively, and with design pressure ratio of 2.05

NASA Technical Reports Server (NTRS)

Moore, R. D.; Reid, L.

1980-01-01

The overall and blade-element performances of a low-aspect-ratio transonic compressor stage are presented over the stable operating flow range for speeds from 50 to 100 percent of design. At design speed the rotor and stage achieved peak efficiencies of 0.876 and 0.840 at pressure ratios of 2.056 and 2.000, respectively. The stage stall margin at design speed was 10 percent.

Influence of magnesia-to-phosphate molar ratio on microstructures, mechanical properties and thermal conductivity of magnesium potassium phosphate cement paste with large water-to-solid ratio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Biwan, E-mail: xubiwan@gmail.com; Ma, Hongyan, E-mail: mhy1103@gmail.com; Li, Zongjin

2015-02-15

This paper describes the influence of the magnesia-to-phosphate (M/P) molar ratios ranging from 4 to 12, on the properties and microstructures of magnesium potassium phosphate cement (MKPC) pastes with a large water-to-solid ratio (w/s) of 0.50. The setting behavior, compressive strength, tensile bonding strength and thermal conductivity of the MKPC pastes, were investigated. The results show that an increase in the M/P ratio can slow down the setting reaction, and clearly degrade the mechanical strengths, but clearly improve the thermal conductivity of MKPC pastes. Furthermore, micro-characterizations including X-ray diffraction, scanning electron microscopy and thermogravimetric analysis, on the MKPC pastes revealmore » that a lower M/P ratio can facilitate better crystallization of the resultant magnesium potassium phosphate hexahydrate (MKP) and a denser microstructure. Moreover, strong linear correlations are found between the mechanical strengths and the MKP-to-space ratio, and between thermal conductivity and the volume ratio of the unreacted magnesia to the MKP. - Highlights: • Increase of M/P molar ratio causes clear mechanical degradations on MKPC pastes. • Thermal conductivity of MKPC pastes is improved with increase of M/P molar ratio. • Lower M/P ratio leads to better MKP crystallization and denser microstructure. • Strengths of MKPC pastes are linearly correlated to the MKP-to-space ratios. • Thermal conductivity is affected by the volume ratio of unreacted magnesia to MKP.« less

Tourniquet use during total knee arthroplasty does not modulate the neutrophil-to-lymphocyte ratio, pain, or activity.

PubMed

Barker, Tyler; Rogers, Victoria E; Brown, Kimberly B; Henriksen, Vanessa T; Rasmussen, G Lynn

2017-09-01

The purpose of our study was to identify the influence of tourniquet use during total knee arthroplasty (TKA) on the neutrophil-to-lymphocyte ratio (NLR) shortly after surgery and patient-reported outcomes (pain and physical activity) from outpatient physical therapy. This retrospective study consisted of 104 subjects who underwent primary unilateral TKA (51 subjects with and 53 subjects without tourniquet assistance) between 2010 and 2012. The NLR was calculated from the absolute neutrophil and lymphocyte counts obtained immediately before and after (1 and 2 days) knee arthroplasty. The Knee Outcome Survey (KOS) of Activities of Daily Living and numeric pain scores collected at the first [33.0 (34.2) days after surgery] and last [85.5 (40.7) days after surgery] outpatient physical therapy visits were extracted from an electronic database. The NLR, pain, and KOS score were not significantly (all p > 0.05) different with tourniquet use. Based on these findings, we conclude that tourniquet use during TKA neither increases systemic inflammation shortly after surgery nor impairs patient-reported outcomes obtained during outpatient physical therapy. IV.

Evaluation of Cadmium Ratio and Foil Activation Measurements for a Beryllium-Reflected Assembly of U(93.15)O 2 Fuel Rods (1.506-cm Triangular Pitch)

DOE PAGES

Marshall, Margaret A.

2014-11-04

A series of small, compact critical assembly (SCCA) experiments were completed from 1962 to 1965 at Oak Ridge National Laboratory’s Critical Experiments Facility (ORCEF) in support of the Medium-Power Reactor Experiments (MPRE) program. Initial experiments, performed in November and December of 1962, consisted of a core of un-moderated stainless-steel tubes, each containing 26 UOIdaho National Laboratory (INL), Idaho Falls, ID (United States) fuel pellets, surrounded by a graphite reflector. Measurements were performed to determine critical reflector arrangements, fission-rate distributions, and cadmium ratio distributions. The graphite reflectors were then changed to beryllium reflectors. For the beryllium reflected assemblies, the fuel wasmore » in 1.506-cm-triangular and 7-tube clusters leading to two critical configurations. Once the critical configurations had been achieved, various measurements of reactivity, relative axial and radial activation rates of 235U, and cadmium ratios were performed. The cadmium ratio, reactivity, and activation rate measurements, performed on the 1.506-cm-array critical configuration, have been evaluated and are described in this paper.« less

Inter-Annual Variability of Fledgling Sex Ratio in King Penguins.

PubMed

Bordier, Célia; Saraux, Claire; Viblanc, Vincent A; Gachot-Neveu, Hélène; Beaugey, Magali; Le Maho, Yvon; Le Bohec, Céline

2014-01-01

As the number of breeding pairs depends on the adult sex ratio in a monogamous species with biparental care, investigating sex-ratio variability in natural populations is essential to understand population dynamics. Using 10 years of data (2000-2009) in a seasonally monogamous seabird, the king penguin (Aptenodytes patagonicus), we investigated the annual sex ratio at fledging, and the potential environmental causes for its variation. Over more than 4000 birds, the annual sex ratio at fledging was highly variable (ranging from 44.4% to 58.3% of males), and on average slightly biased towards males (51.6%). Yearly variation in sex-ratio bias was neither related to density within the colony, nor to global or local oceanographic conditions known to affect both the productivity and accessibility of penguin foraging areas. However, rising sea surface temperature coincided with an increase in fledging sex-ratio variability. Fledging sex ratio was also correlated with difference in body condition between male and female fledglings. When more males were produced in a given year, their body condition was higher (and reciprocally), suggesting that parents might adopt a sex-biased allocation strategy depending on yearly environmental conditions and/or that the effect of environmental parameters on chick condition and survival may be sex-dependent. The initial bias in sex ratio observed at the juvenile stage tended to return to 1∶1 equilibrium upon first breeding attempts, as would be expected from Fisher's classic theory of offspring sex-ratio variation.

Does the Mother or Father Determine the Offspring Sex Ratio? Investigating the Relationship between Maternal Digit Ratio and Offspring Sex Ratio

PubMed Central

Kim, Tae Beom; Oh, Jin Kyu; Kim, Kwang Taek; Yoon, Sang Jin; Kim, Soo Woong

2015-01-01

Objective In mammals, high parental testosterone levels present around the time of conception are thought to skew offspring sex ratio toward sons. The second to fourth digit ratio (digit ratio) is now widely accepted as a negative correlate of prenatal testosterone. Thus, we investigated the association between digit ratio and offspring sex ratio. Methods A total of 508 Korean patients (257 males and 251 females) less than 60 years old who had one or more offspring were prospectively enrolled. The lengths of the 2nd and 4th digits of the right hand were measured by a single investigator using a digital vernier calliper. Next, the patients’ lifetime offspring birth sex ratios were investigated. Results Maternal (rather than paternal) digit ratio was significantly associated with the number of sons (r = -0.153, p = 0.015), number of daughters (r = 0.130, p = 0.039), and offspring sex ratio (r = -0.171, p = 0.007). And, the maternal digit ratio was a significant factor for predicting offspring sex ratio (B = -1.620, p = 0.008) on multiple linear regression analysis. The female patients with a lower digit ratio (< 0.95) were found to have a higher offspring sex ratio (0.609 versus 0.521, p = 0.046) compared to those with a higher digit ratio (≥ 0.95). Furthermore, females in the low digit ratio group have a probability 1.138 greater of having sons than females in the high digit ratio group. Conclusions Maternal digit ratio was negatively associated with offspring sex ratio. Females with a lower digit ratio were more likely to have more male offspring compared to those with a higher digit ratio. Thus, our results suggest that the sex of offspring might be more influenced by maternal rather than paternal factors. PMID:26575995

Active thermal fine laser tuning in a broad spectral range and optical properties of cholesteric liquid crystal.

PubMed

Jeong, Mi-Yun; Kwak, Keumcheol

2016-11-20

In this study, we achieved active fine laser tuning in a broad spectral range with dye-doped cholesteric liquid crystal wedge-type cells through temperature control. The spatial pitch gradient of each position of the wedge cell at room temperature was almost maintained after developing a temperature gradient. To achieve the maximum tuning range, the chiral dopant concentration, thickness, thickness gradient, and temperature gradient on the wedge cell should be matched properly. In order to understand the laser tuning mechanism for temperature change, we studied the temperature dependence of optical properties of the photonic bandgap of cholesteric liquid crystals. In our cholesteric liquid crystal samples, when temperature was increased, photonic bandgaps were shifted toward blue, while the width of the photonic bandgap was decreased, regardless of whether the helicity was left-handed or right-handed. This is mainly due to the combination of decreased refractive indices, higher molecular anisotropy of chiral molecules, and increased chiral molecular solubility. We envisage that this kind of study will prove useful in the development of practical active tunable CLC laser devices.

Organization of Functional Long-Range Circuits Controlling the Activity of Serotonergic Neurons in the Dorsal Raphe Nucleus.

PubMed

Zhou, Li; Liu, Ming-Zhe; Li, Qing; Deng, Juan; Mu, Di; Sun, Yan-Gang

2017-03-21

Serotonergic neurons play key roles in various biological processes. However, circuit mechanisms underlying tight control of serotonergic neurons remain largely unknown. Here, we systematically investigated the organization of long-range synaptic inputs to serotonergic neurons and GABAergic neurons in the dorsal raphe nucleus (DRN) of mice with a combination of viral tracing, slice electrophysiological, and optogenetic techniques. We found that DRN serotonergic neurons and GABAergic neurons receive largely comparable synaptic inputs from six major upstream brain areas. Upon further analysis of the fine functional circuit structures, we found both bilateral and ipsilateral patterns of topographic connectivity in the DRN for the axons from different inputs. Moreover, the upstream brain areas were found to bidirectionally control the activity of DRN serotonergic neurons by recruiting feedforward inhibition or via a push-pull mechanism. Our study provides a framework for further deciphering the functional roles of long-range circuits controlling the activity of serotonergic neurons in the DRN. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Variations in Ratio and Correlation of Solar Magnetic Fields in the Fe i 525.02 nm and Na i 589.59 nm Lines According to Mount Wilson Measurements During 2000 - 2012

NASA Astrophysics Data System (ADS)

Golubeva, Elena

2016-10-01

Variations in the solar magnetic-field ratio over 13 years are analyzed, relying on the comparison of simultaneous measurements in two spectral lines at the Mount Wilson Observatory (MWO). The ratio and correlation coefficient are calculated over the general working range of measured magnetic-field values and in various ranges of the field magnitudes. Variations in both parameters are considered. We found the following tendencies: i) the parameters show changes with the cycle of solar activity in the general case; ii) their dependence on magnetic-field magnitude is a nonlinear function of time, and this is especially pronounced in the ratio behavior; iii) several separate ranges of the field magnitudes can be distinguished based on the behavioral patterns of the ratio variations. Correspondences between these ranges and the known structural objects of the solar atmosphere are discussed. This permits us to reach the conclusion that the dependence of parameters considered on the magnetic-field magnitude and time is connected with the variety of magnetic structural components and their cyclic rearrangements. The results represented may be useful for solving interpretation problems of solar magnetic-field measurements and for the cross-calibration of applicable instruments. They can also be of interest for tasks related to the creation of a uniform long temporal series of solar magnetic-field data from various sources.

Harnessing out-of-plane deformation to design 3D architected lattice metamaterials with tunable Poisson's ratio.

PubMed

Li, Tiantian; Hu, Xiaoyi; Chen, Yanyu; Wang, Lifeng

2017-08-21

Auxetic materials exhibiting a negative Poisson's ratio are of great research interest due to their unusual mechanical responses and a wide range of potential deployment. Efforts have been devoted to exploring novel 2D and 3D auxetic structures through rational design, optimization, and taking inspiration from nature. Here we report a 3D architected lattice system showing a negative Poisson's ratio over a wide range of applied uniaxial stretch. 3D printing, experimental tests, numerical simulation, and analytical modeling are implemented to quantify the evolution of the Poisson's ratio and reveal the underlying mechanisms responsible for this unusual behavior. We further show that the auxetic behavior can be controlled by tailoring the geometric features of the ligaments. The findings reported here provide a new routine to design architected metamaterial systems exhibiting unusual properties and having a wide range of potential applications.

Feed-conversion ratio of finisher pigs in the USA.

PubMed

Losinger, W C

1998-10-09

Although the feed-conversion ratio is recognized as a prominent indicator of profitability for pork producers, only 212 (50.7%) of 418 producers who were asked the feed-conversion ratio for finisher pigs provided a response during the USA National Animal Health Monitoring System 1995 National Swine Study. Of these, 126 (59.4%) producers furnished a feed-conversion ratio which they characterized as having been calculated from records, while 86 (40.6%) gave a response that they characterized as estimated or guessed. Feed-conversion ratios ranged from 2.18 to 5.91 kg of feed fed for each kg of live-body weight gained during the grower/finisher phase, with a mean of 3.28 and a standard deviation of 0.52. Stepwise regression revealed the following management factors to be associated with improved feed-conversion ratios: > or = 3 different rations fed during the grower/finisher phase (P < 0.01); no rations mixed on the farm (P < 0.05); and not giving chlortetracycline in feed or water as a disease preventive or growth promotant (P < 0.01). In addition, operations where > or = 3000 pigs entered the grower/finisher-production phase during the six-month period prior to interview had a better mean feed-conversion ratio than operations where < 3000 pigs entered the grower/finisher phase (P < 0.01).

A Lactobacillus plantarum Esterase Active on a Broad Range of Phenolic Esters

PubMed Central

Esteban-Torres, María; Landete, José María; Reverón, Inés; Santamaría, Laura; de las Rivas, Blanca

2015-01-01

Lactobacillus plantarum is the lactic acid bacterial species most frequently found in the fermentation of food products of plant origin on which phenolic compounds are abundant. L. plantarum strains showed great flexibility in their ability to adapt to different environments and growth substrates. Of 28 L. plantarum strains analyzed, only cultures from 7 strains were able to hydrolyze hydroxycinnamic esters, such as methyl ferulate or methyl caffeate. As revealed by PCR, only these seven strains possessed the est_1092 gene. When the est_1092 gene was introduced into L. plantarum WCFS1 or L. lactis MG1363, their cultures acquired the ability to degrade hydroxycinnamic esters. These results support the suggestion that Est_1092 is the enzyme responsible for the degradation of hydroxycinnamic esters on the L. plantarum strains analyzed. The Est_1092 protein was recombinantly produced and biochemically characterized. Surprisingly, Est_1092 was able to hydrolyze not only hydroxycinnamic esters, since all the phenolic esters assayed were hydrolyzed. Quantitative PCR experiments revealed that the expression of est_1092 was induced in the presence of methyl ferulate, an hydroxycinnamic ester, but was inhibited on methyl gallate, an hydroxybenzoic ester. As Est_1092 is an enzyme active on a broad range of phenolic esters, simultaneously possessing feruloyl esterase and tannase activities, its presence on some L. plantarum strains provides them with additional advantages to survive and grow on plant environments. PMID:25746986

210Po/210Pb Activity Ratios as a Possible `Dating Tool' of Ice Cores and Ice-rafted Sediments from the Western Arctic Ocean - Preliminary Results

NASA Astrophysics Data System (ADS)

Krupp, K.; Baskaran, M. M.

2016-02-01

We have collected and analyzed a suite of surface snow samples, ice cores, ice-rafted sediments (IRS) and aerosol samples from the Western Arctic for Po-210 and Pb-210 to examine the extent of disequilibrium between this pair to possibly use 210Po/210Pb activity ratio to date different layers of ice cores and time of incorporation of ice-rafted sediments into the sea ice. We have earlier reported that the activity concentrations of 210Pb in IRS vary over an order of magnitude and it is 1-2 orders of magnitude higher than that of the benthic sediments (1-2 dpm/g in benthic sediments compared to 25 to 300 dpm/g in IRS). In this study, we have measured 210Po/210Pb activity ratios in aerosols from the Arctic Ocean to constrain the initial 210Po/210Pb ratio at the time of deposition during precipitation. The 210Po activity concentration in recent snow is compared to surface ice samples. The `age' of IRS incorporation can be calculated as follows: [210Po]measured = [210Po]initial + [210Pb] (1 - exp(-λt)) (1) where λ is the decay constant of 210Po, 138.4 days, and `t' is the in-growth time period. From this equation, `t' can be calculated as follows: t = (-1/λ) [ln (1- ((210Po/210Pb)measured - (210Po/210Pb)initial)] (2) The assumption involved in this approach are: i) there is no preferential uptake of 210Po (highly biogenic - S group); and iii) both 210Po and 210Pb remain as closed system. The calculated age using equation (2) will be discussed and presented.

Electron-density-sensitive Line Ratios of Fe xiii– xvi from Laboratory Sources Compared to CHIANTI

DOE PAGES

Weller, M. E.; Beiersdorfer, P.; Soukhanovskii, V. A.; ...

2018-02-15

We present electron-density-sensitive line ratios for Fe xiii– xvi measured in the spectral wavelength range of 200–440 Å and an electron density range of (1-4) × 10 13 cm -3. The results provide a test at the high-density limit of density-sensitive line ratios useful for astrophysical studies. The measurements were performed on the National Spherical Torus Experiment-Upgrade, where electron densities were measured independently by the laser Thomson scattering diagnostic. Spectra were collected with a flat-field grazing-incidence spectrometer, which provided a spectral resolution of up to 0.3 Å, i.e., high resolution across the broad wavelength range. The response of the instrumentmore » was relatively calibrated using spectroscopic techniques in order to improve accuracy. Lastly, the line ratios are compared to other laboratory sources and the latest version of CHIANTI (8.0.2), and an agreement within 30% is found.« less

Electron-density-sensitive Line Ratios of Fe xiii– xvi from Laboratory Sources Compared to CHIANTI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weller, M. E.; Beiersdorfer, P.; Soukhanovskii, V. A.

We present electron-density-sensitive line ratios for Fe xiii– xvi measured in the spectral wavelength range of 200–440 Å and an electron density range of (1-4) × 10 13 cm -3. The results provide a test at the high-density limit of density-sensitive line ratios useful for astrophysical studies. The measurements were performed on the National Spherical Torus Experiment-Upgrade, where electron densities were measured independently by the laser Thomson scattering diagnostic. Spectra were collected with a flat-field grazing-incidence spectrometer, which provided a spectral resolution of up to 0.3 Å, i.e., high resolution across the broad wavelength range. The response of the instrumentmore » was relatively calibrated using spectroscopic techniques in order to improve accuracy. Lastly, the line ratios are compared to other laboratory sources and the latest version of CHIANTI (8.0.2), and an agreement within 30% is found.« less

Diffuse-direct ultraviolet ratios with a compact double monochromator

NASA Technical Reports Server (NTRS)

Garrison, L. M.; Murray, L. E.; Doda, D. D.; Green, A. E. S.

1978-01-01

An improved system has been implemented for measuring the ratio of the diffuse skylight to the direct sunlight in the biologically active region of the UV near the atmospheric limit. It combines a double monochromator employing holographic gratings for reduction of stray light with a cooled photomultiplier tube to provide a greatly improved SNR below 300 nm. Data may be obtained in either a scan mode or a narrowband photometry mode; in the latter mode accurate ratios have been obtained near 290 nm. Representative data are discussed along with a theoretical model of the ratio. The system is compact enough for use in a mobile monitoring system.

Changes in Upper Extremity Range of Motion and Efficiency in Multiple Sclerosis Patients Due to Water Activity.

ERIC Educational Resources Information Center

Duthie, Pamela Rae

To determine the effects of water exercise on the movements of multiple sclerosis patients, this study utilized tests to determine changes in the linear range of motion of the shoulder, elbow, and wrist after a 45-minute period of water activities and to determine if the movement became more effective. The test used was an overhead throw with a…

Effects of Fineness Ratio and Reynolds Number on the Low-Speed Crosswind Drag Characteristics of Circular and Modified-Square Cylinders

NASA Technical Reports Server (NTRS)

McKinney, Linwood W.

1960-01-01

A wind-tunnel investigation has been made on modified-square and circular cylinders to determine the effects of fineness ratio and Reynolds numbers on the crosswind drag characteristics. Fineness ratios from 2 to 14 were investigated over a Reynolds number range from approximately 300,000 to 1,650,000 which corresponded to Mach numbers from 0.057 to 0.377.The result of the investigation show that at supercraft Reynolds numbers the drag coefficient of the circular cylinder increases with increasing Reynolds number for all fineness ratios but at low fineness ratios this effect is considerably less than at higher fineness ratios. For circular cylinders in the high fineness-ratio range there is a reduction in drag as the fineness ratio is decreased except for Reynolds numbers of 900,000 and 1,000,000, whereas at low fineness ratios the opposite trend generally occurs. The addition of hemispherical ends to the circular cylinder gave a substantial decrease in drag at a fineness ratio of 3.27 but the effect was negligible at fineness ratios of 5.27 and 10. The finite-length modified-square cylinder gave the reduction in drag over the two-dimensional modified-square cylinder for the complete range of test Reynolds numbers with the lowest fineness ratio giving the lowest drag at Reynolds numbers above 3O0,OOO.

Calculation and usage of the thyroid to background ratio on the pertechnetate thyroid scan.

PubMed

Wallack, Seth; Metcalf, Michelle; Skidmore, Angela; Lamb, Christopher R

2010-01-01

Feline hyperthyroidism is a common endocrine disorder. A single dose of 148MBq (4mCi) 131I is 95-98% effective for the treatment of hyperthyroidism in cats; however, the cause for treatment failures has not been determined. In a series of 113 hyperthyroid cats having pertechnetate thyroid scintigraphy before treatment using a standard 148MBq (4mCi) 131I dose, the thyroid to salivary gland (T:S) ratio and the thyroid to background (T:B) ratio were calculated. Results in 107 (95%) cats successfully treated were compared with results in six (5%) cats that remained hyperthyroid after treatment. T:B ratio was significantly higher for cats that had treatment failure (median 13.0, range 3.6-73.0) than for cats successfully treated (median 4.4, range 1.2-69.0) (P = 0.02), whereas there was no significant difference in their T:S ratios (P = 0.2). The T:B ratio is a new approach to evaluating the thyroid pertechnetate scan with the intent of identifying which hyperthyroid cats may fail treatment using a standard 148 MBq (4 mCi) 131 dose and which, therefore, require a higher dose.