Poisson's ratio of fiber-reinforced composites

Science.gov (United States)

Christiansson, Henrik; Helsing, Johan

1996-05-01

Poisson's ratio flow diagrams, that is, the Poisson's ratio versus the fiber fraction, are obtained numerically for hexagonal arrays of elastic circular fibers in an elastic matrix. High numerical accuracy is achieved through the use of an interface integral equation method. Questions concerning fixed point theorems and the validity of existing asymptotic relations are investigated and partially resolved. Our findings for the transverse effective Poisson's ratio, together with earlier results for random systems by other authors, make it possible to formulate a general statement for Poisson's ratio flow diagrams: For composites with circular fibers and where the phase Poisson's ratios are equal to 1/3, the system with the lowest stiffness ratio has the highest Poisson's ratio. For other choices of the elastic moduli for the phases, no simple statement can be made.

Detecting isotopic ratio outliers

Science.gov (United States)

Bayne, C. K.; Smith, D. H.

An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers.

Detecting isotopic ratio outliers

International Nuclear Information System (INIS)

Bayne, C.K.; Smith, D.H.

1986-01-01

An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers

Arcjet nozzle area ratio effects

Science.gov (United States)

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

Science.gov (United States)

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.

Deriving aerosol scattering ratio using range-resolved lidar ratio

Indian Academy of Sciences (India)

2014-02-13

Feb 13, 2014 ... ratio (LDR) are used to suggest the type of aerosols. The altitude-dependent ... to the station and the experimentally measured lidar data. The 'model ... The integrated aerosol extinction profile with altitude-dependent S and k.

Detecting isotopic ratio outliers

International Nuclear Information System (INIS)

Bayne, C.K.; Smith, D.H.

1985-01-01

An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers. 6 refs., 3 figs., 3 tabs

Holes at High Blowing Ratios

Directory of Open Access Journals (Sweden)

Phillip M. Ligrani

1996-01-01

Full Text Available Experimental results are presented which describe the development and structure of flow downstream of a single row of holes with compound angle orientations producing film cooling at high blowing ratios. This film cooling configuration is important because similar arrangements are frequently employed on the first stage of rotating blades of operating gas turbine engines. With this configuration, holes are spaced 6d apart in the spanwise direction, with inclination angles of 24 degrees, and angles of orientation of 50.5 degrees. Blowing ratios range from 1.5 to 4.0 and the ratio of injectant to freestream density is near 1.0. Results show that spanwise averaged adiabatic effectiveness, spanwise-averaged iso-energetic Stanton number ratios, surveys of streamwise mean velocity, and surveys of injectant distributions change by important amounts as the blowing ratio increases. This is due to injectant lift-off from the test surface just downstream of the holes.

Regulation of the Docosapentaenoic Acid/Docosahexaenoic Acid Ratio (DPA/DHA Ratio) in Schizochytrium limacinum B4D1.

Science.gov (United States)

Zhang, Ke; Li, Huidong; Chen, Wuxi; Zhao, Minli; Cui, Haiyang; Min, Qingsong; Wang, Haijun; Chen, Shulin; Li, Demao

2017-05-01

Docosapentaenoic acid/docosahexaenoic acid ratio (DPA/DHA ratio) in Schizochytrium was relatively stable. But ideally the ratio of DPA/DHA will vary according to the desired end use. This study reports several ways of modulating the DPA/DHA ratio. Incubation times changed the DPA/DHA ratio, and changes in this ratio were associated with the variations in the saturated fatty acid (SFAs) content. Propionic acid sharply increased the SFAs content in lipids, dramatically decreased the even-chain SFAs content, and reduced the DPA/DHA ratio. Pentanoic acid (C5:0) and heptanoic acid (C7:0) had similar effects as propionic acid, whereas butyric acid (C4:0), hexanoic acid (C6:0), and octanoic acid (C8:0) did not change the fatty acid profile and the DPA/DHA ratio. Transcription analyses show that β-oxidation might be responsible for this phenomenon. Iodoacetamide upregulated polyunsaturated fatty acid (PUFA) synthase genes, reduced the DHA content, and improved the DPA content, causing the DPA/DHA ratio to increase. These results present new insights into the regulation of the DPA/DHA ratio.

Large aspect ratio tokamak study

International Nuclear Information System (INIS)

Reid, R.L.; Holmes, J.A.; Houlberg, W.A.; Peng, Y.K.M.; Strickler, D.J.; Brown, T.G.; Sardella, C.; Wiseman, G.W.

1979-01-01

The Large Aspect Ratio Tokamak Study (LARTS) investigated the potential for producing a viable long burn tokamak reactor through enhanced volt-second capability of the ohmic heating transformer by employing high aspect ratio designs. The plasma physics, engineering, and economic implications of high aspect ratio tokamaks were accessed in the context of extended burn operation. Plasma startup and burn parameters were addressed using a one-dimensional transport code. The pulsed electrical power requirements for the poloidal field system, which have a major impact on reactor economics, were minimized by optimizing the field in the ohmic heating coil and the wave shape of the ohmic heating discharge. A high aspect ratio reference reactor was chosen and configured

Using Ratio Analysis to Evaluate Financial Performance.

Science.gov (United States)

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)

Estimating 24-h urinary sodium/potassium ratio from casual ('spot') urinary sodium/potassium ratio: the INTERSALT Study.

Science.gov (United States)

Iwahori, Toshiyuki; Miura, Katsuyuki; Ueshima, Hirotsugu; Chan, Queenie; Dyer, Alan R; Elliott, Paul; Stamler, Jeremiah

2017-10-01

Association between casual and 24-h urinary sodium-to-potassium (Na/K) ratio is well recognized, although it has not been validated in diverse demographic groups. Our aim was to assess utility across and within populations of casual urine to estimate 24-h urinary Na/K ratio using data from the INTERSALT Study. The INTERSALT Study collected cross-sectional standardized data on casual urinary sodium and potassium and also on timed 24-h urinary sodium and potassium for 10 065 individuals from 52 population samples in 32 countries (1985-87). Pearson correlation coefficients and agreement were computed for Na/K ratio of casual urine against 24-h urinary Na/K ratio both at population and individual levels. Pearson correlation coefficients relating means of 24-h urine and casual urine Na/K ratio were r = 0.96 and r = 0.69 in analyses across populations and individuals, respectively. Correlations of casual urine Na/creatinine and K/creatinine ratios with 24-h urinary Na and K excretion, respectively, were lower than correlation of casual and 24-h urinary Na/K ratio in analyses across populations and individuals. The bias estimate with the Bland-Altman method, defined as the difference between Na/K ratio of 24-h urine and casual urine, was approximately 0.4 across both populations and individuals. Spread around, the mean bias was higher for individuals than populations. With appropriate bias correction, casual urine Na/K ratio may be a useful, low-burden alternative method to 24-h urine for estimation of population urinary Na/K ratio. It may also be applicable for assessment of the urinary Na/K ratio of individuals, with use of repeated measurements to reduce measurement error and increase precision. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association

Energy ratios in Finnish agricultural production

Directory of Open Access Journals (Sweden)

H. J. MIKKOLA

2008-12-01

Full Text Available The objective of this study was to assess energy ratios and net energy in plant production and energy ratios in animal production in Finland. Energy ratios and net energy were determined on the basis of plant- and animal-specific energy analyses. In plant production, energy ratios and net energy were assessed as a function of nitrogen fertilization, because indirect energy input in the form of agrochemicals was 54—73% from the total energy input and nitrogen was responsible for the major part of this. The highest energy ratio was 18.6 for reed canary grass. As a whole reed canary grass was superior to the other crops, which were barley, spring wheat, spring turnip rape, ley for silage, potato and sugar beet. Reed canary grass and sugar beet gained the highest net energy yields of 111–115 GJ ha-1. The optimum energy ratio was gained in general with less nitrogen fertilization intensity than farmers use. The energy ratios in pork production varied between 0.14–1.28 depending on what was included or excluded in the analysis and for milk production between 0.15–1.85. Ratios of 1.28 in pork production and 1.85 in milk production are unrealistic as they do not give any shelter to the animals, although they can be approached in very low-input production systems. If the ratio is calculated with feed energy content then the ratio is low, 0.14–0.22 for pork and 0.15 for milk. This shows that animals can convert 14–22 percent of the input energy to usable products. In pork production, the largest portion of the energy input was the ventilation of the building. In milk production milking and cooling consumes a lot of energy and for this reason the electricity consumption is high.;

Output factors and scatter ratios

Energy Technology Data Exchange (ETDEWEB)

Shrivastava, P N; Summers, R E; Samulski, T V; Baird, L C [Allegheny General Hospital, Pittsburgh, PA (USA); Ahuja, A S; Dubuque, G L; Hendee, W R; Chhabra, A S

1979-07-01

Reference is made to a previous publication on output factors and scatter ratios for radiotherapy units in which it was suggested that the output factor should be included in the definitions of scatter-air ratio and tissue-maximum ratio. In the present correspondence from other authors and from the authors of the previous publication, the original definitions and the proposed changes are discussed. Radiation scatter from source and collimator degradation of beam energy and calculation of dose in tissue are considered in relation to the objective of accurate dosimetry.

Influence of La/W ratio on electrical conductivity of lanthanum tungstate with high La/W ratio

International Nuclear Information System (INIS)

Kojo, Gen; Shono, Yohei; Ushiyama, Hiroshi; Oshima, Yoshito; Otomo, Junichiro

2017-01-01

The proton-conducting properties of lanthanum tungstates (LWOs) with high La/W ratios were investigated using electrochemical measurements and quantum chemical calculations. Single phases of LWOs with high La/W ratios (6.3≤La/W≤6.7) were synthesized by high-temperature sintering at around 1700 °C. The electrical conductivity of LWO increased with increasing La/W ratio in the single-phase region. The LWO synthesized at the optimum sintering temperature and time, and with the optimum La/W ratio gave the maximum conductivity, i.e., 2.7×10 −3 S cm −1 with La/W=6.7 at 500 °C. Density functional theory calculations, using the nudged elastic band method, were performed to investigate the proton diffusion barrier. The results suggest that the proton diffusion paths around La sites have the lowest proton diffusion barrier. These findings improve our understanding of LWO synthesis and the proton-conducting mechanism and provide a strategy for improving proton conduction in LWOs. - Graphical abstract: The LWOs with high La/W ratios were synthesized for the first time. The optimum La/W ratio gave the maximum conductivity with La/W=6.7 at 500 °C. The proton diffusion paths were also considered with density functional theory calculations. - Highlights: • The proton-conducting properties of lanthanum tungstates (LWOs) were investigated. • Single phase LWOs with high La/W ratios (6.3≤La/W≤6.7) were synthesized successfully. • LWOs with the high La/W ratios showed high proton conductivity. • The DFT calculation suggested the lowest proton diffusion barrier in the path around La sites.

Liquidity Analysis Using Cash Flow Ratios as Compared to Traditional Ratios in the Pharmaceutical Sector in Jordan

OpenAIRE

Sulayman H. Atieh

2014-01-01

The purpose of this study is to examine the liquidity position of the Jordanian pharmaceutical sector using the traditional ratios as compared to the more recently developed cash flow ratios. The research involved the comparison between traditional ratios and cash flow ratios of the big seven companies of the pharmaceutical industry in Jordan over six years period (2007¨C2012). The companies were all from the same sector, and the data was obtained from the annual reports of these companies. T...

A Study on the Effects of Compression Ratio, Engine Speed and Equivalence Ratio on HCCI Combustion of DME

DEFF Research Database (Denmark)

Pedersen, Troels Dyhr; Schramm, Jesper

2007-01-01

An experimental study has been carried out on the homogeneous charge compression ignition (HCCI) combustion of Dimethyl Ether (DME). The study was performed as a parameter variation of engine speed and compression ratio on excess air ratios of approximately 2.5, 3 and 4. The compression ratio...... was adjusted in steps to find suitable regions of operation, and the effect of engine speed was studied at 1000, 2000 and 3000 RPM. It was found that leaner excess air ratios require higher compression ratios to achieve satisfactory combustion. Engine speed also affects operation significantly....

Difference and ratio plots

DEFF Research Database (Denmark)

Svendsen, Anders Jørgen; Holmskov, U; Bro, Peter

1995-01-01

and systemic lupus erythematosus from another previously published study (Macanovic, M. and Lachmann, P.J. (1979) Clin. Exp. Immunol. 38, 274) are also represented using ratio plots. Our observations indicate that analysis by regression analysis may often be misleading....... hitherto unnoted differences between controls and patients with either rheumatoid arthritis or systemic lupus erythematosus. For this we use simple, but unconventional, graphic representations of the data, based on difference plots and ratio plots. Differences between patients with Burkitt's lymphoma...

High ratio recirculating gas compressor

Science.gov (United States)

Weinbrecht, J.F.

1989-08-22

A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

The ATP/DNA Ratio Is a Better Indicator of Islet Cell Viability Than the ADP/ATP Ratio

Science.gov (United States)

Suszynski, T.M.; Wildey, G.M.; Falde, E.J.; Cline, G.W.; Maynard, K. Stewart; Ko, N.; Sotiris, J.; Naji, A.; Hering, B.J.; Papas, K.K.

2009-01-01

Real-time, accurate assessment of islet viability is critical for avoiding transplantation of nontherapeutic preparations. Measurements of the intracellular ADP/ATP ratio have been recently proposed as useful prospective estimates of islet cell viability and potency. However, dead cells may be rapidly depleted of both ATP and ADP, which would render the ratio incapable of accounting for dead cells. Since the DNA of dead cells is expected to remain stable over prolonged periods of time (days), we hypothesized that use of the ATP/DNA ratio would take into account dead cells and may be a better indicator of islet cell viability than the ADP/ATP ratio. We tested this hypothesis using mixtures of healthy and lethally heat-treated (HT) rat insulinoma cells and human islets. Measurements of ATP/DNA and ADP/ATP from the known mixtures of healthy and HT cells and islets were used to evaluate how well these parameters correlated with viability. The results indicated that ATP and ADP were rapidly (within 1 hour) depleted in HT cells. The fraction of HT cells in a mixture correlated linearly with the ATP/DNA ratio, whereas the ADP/ADP ratio was highly scattered, remaining effectively unchanged. Despite similar limitations in both ADP/ADP and ATP/DNA ratios, in that ATP levels may fluctuate significantly and reversibly with metabolic stress, the results indicated that ATP/DNA was a better measure of islet viability than the ADP/ATP ratio. PMID:18374063

Application of Performance Ratios in Portfolio Optimization

Directory of Open Access Journals (Sweden)

Aleš Kresta

2015-01-01

Full Text Available The cornerstone of modern portfolio theory was established by pioneer work of Harry Markowitz. Based on his mean-variance framework, Sharpe formulated his well-known Sharpe ratio aiming to measure the performance of mutual funds. The contemporary development in computer’s computational power allowed to apply more complex performance ratios, which take into account also higher moments of return probability distribution. Although these ratios were proposed to help the investors to improve the results of portfolio optimization, we empirically demonstrated in our paper that this may not necessarily be true. On the historical dataset of DJIA components we empirically showed that both Sharpe ratio and MAD ratio outperformed Rachev ratio. However, for Rachev ratio we assumed only one level of parameters value. Different set-ups of parameters may provide different results and thus further analysis is certainly required.

A note on trader Sharpe Ratios.

Science.gov (United States)

Coates, John M; Page, Lionel

2009-11-25

Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D), which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

A note on trader Sharpe Ratios.

Directory of Open Access Journals (Sweden)

John M Coates

Full Text Available Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D, which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

Isokinetic Hamstrings: Quadriceps Ratios in Intercollegiate Athletes.

Science.gov (United States)

Rosene, John M.; Fogarty, Tracey D.; Mahaffey, Brian L.

2001-01-01

Compared the differences in the concentric hamstrings to quadriceps (H:Q) ratio among athletes in different sports at three velocities. Measurement of H:Q ratio of both knees among male and female college athletes indicated that the H:Q ratio increased as velocity increased. No differences existed for the H:Q ratio for sport or side of body. (SM)

Fast fission ratio and relative conversion ratio measurements in gadolinium poisoned water moderated UO2 lattices

International Nuclear Information System (INIS)

Murphy, M.F.

1984-01-01

A programme of criticality experiments has been carried out for BNFL by the Battelle reactor facility at Pacific Northwest Laboratories in Washington State, USA. A series of water moderated lattices of 4.3% enriched, 12.7 mm diameter, UO 2 fuel rods was studied, the fuel pitch was varied and the effects of gadolinium poison were measured. This report deals with the measurement of Fast Fission Ratios and Relative Conversion Ratios at the centre of five of the critical lattices. The Fast Fission Ratio (FFR) is defined here as the ratio of the fission rate per atom of U238, to the fission rate per atom of U235. The Relative Conversion Ratio (RCR) is defined as the ratio of the capture rate per ,atom of U238, to the fission rate per atom of U235, in the reactor fuel, relative to the corresponding ratio in a well thermalised neutron spectrum. A major aspect of these measurements was that the packs of foils were prepared at AEEW Winfrith, despatched to the USA for irradiation and returned to Winfrith for counting. This resulted in a considerable logistics problem but by good planning and the co-operation and diligence of all concerned this problem was overcome. However, the long distance involved inevitably meant that samples were not available for measurement until about 28 hours after the irradiation. It was therefore necessary to modify the techniques that are normally used in the Reactor Physics Division Counting Laboratory, where samples are normally available about two hours after shut-down. The techniques used and the results obtained are given below

effect of effect of blend ratio on blend ratio on characteristics

African Journals Online (AJOL)

User

properties, cassava-soybean composite, wheat, bread, blend ratio ... dily growing population, an in eating and ... thermodynamic variables can produce an effect on .... these conditions. ..... Ragaee, S. et al., Pasting properties of starch and.

Equity Theory Ratios as Causal Schemas

Directory of Open Access Journals (Sweden)

Alexios Arvanitis

2016-08-01

Full Text Available Equity theory approaches justice evaluations based on ratios of exchange inputs to exchange outcomes. Situations are evaluated as just if ratios are equal and unjust if unequal. We suggest that equity ratios serve a more fundamental cognitive function than the evaluation of justice. More particularly, we propose that they serve as causal schemas for exchange outcomes, that is, they assist in determining whether certain outcomes are caused by inputs of other people in the context of an exchange process. Equality or inequality of ratios in this sense points to an exchange process. Indeed, Study 1 shows that different exchange situations, such as disproportional or balanced proportional situations, create perceptions of give-and-take on the basis of equity ratios. Study 2 shows that perceptions of justice are based more on communicatively accepted rules of interaction than equity-based evaluations, thereby offering a distinction between an attribution and an evaluation cognitive process for exchange outcomes.

Equity Theory Ratios as Causal Schemas.

Science.gov (United States)

Arvanitis, Alexios; Hantzi, Alexandra

2016-01-01

Equity theory approaches justice evaluations based on ratios of exchange inputs to exchange outcomes. Situations are evaluated as just if ratios are equal and unjust if unequal. We suggest that equity ratios serve a more fundamental cognitive function than the evaluation of justice. More particularly, we propose that they serve as causal schemas for exchange outcomes, that is, they assist in determining whether certain outcomes are caused by inputs of other people in the context of an exchange process. Equality or inequality of ratios in this sense points to an exchange process. Indeed, Study 1 shows that different exchange situations, such as disproportional or balanced proportional situations, create perceptions of give-and-take on the basis of equity ratios. Study 2 shows that perceptions of justice are based more on communicatively accepted rules of interaction than equity-based evaluations, thereby offering a distinction between an attribution and an evaluation cognitive process for exchange outcomes.

Three-dimensional stereo by photometric ratios

International Nuclear Information System (INIS)

Wolff, L.B.; Angelopoulou, E.

1994-01-01

We present a methodology for corresponding a dense set of points on an object surface from photometric values for three-dimensional stereo computation of depth. The methodology utilizes multiple stereo pairs of images, with each stereo pair being taken of the identical scene but under different illumination. With just two stereo pairs of images taken under two different illumination conditions, a stereo pair of ratio images can be produced, one for the ratio of left-hand images and one for the ratio of right-hand images. We demonstrate how the photometric ratios composing these images can be used for accurate correspondence of object points. Object points having the same photometric ratio with respect to two different illumination conditions constitute a well-defined equivalence class of physical constraints defined by local surface orientation relative to illumination conditions. We formally show that for diffuse reflection the photometric ratio is invariant to varying camera characteristics, surface albedo, and viewpoint and that therefore the same photometric ratio in both images of a stereo pair implies the same equivalence class of physical constraints. The correspondence of photometric ratios along epipolar lines in a stereo pair of images under different illumination conditions is a correspondence of equivalent physical constraints, and the determination of depth from stereo can be performed. Whereas illumination planning is required, our photometric-based stereo methodology does not require knowledge of illumination conditions in the actual computation of three-dimensional depth and is applicable to perspective views. This technique extends the stereo determination of three-dimensional depth to smooth featureless surfaces without the use of precisely calibrated lighting. We demonstrate experimental depth maps from a dense set of points on smooth objects of known ground-truth shape, determined to within 1% depth accuracy

A father effect explains sex-ratio bias.

Science.gov (United States)

Malo, Aurelio F; Martinez-Pastor, Felipe; Garcia-Gonzalez, Francisco; Garde, Julián; Ballou, Jonathan D; Lacy, Robert C

2017-08-30

Sex ratio allocation has important fitness consequences, and theory predicts that parents should adjust offspring sex ratio in cases where the fitness returns of producing male and female offspring vary. The ability of fathers to bias offspring sex ratios has traditionally been dismissed given the expectation of an equal proportion of X- and Y-chromosome-bearing sperm (CBS) in ejaculates due to segregation of sex chromosomes at meiosis. This expectation has been recently refuted. Here we used Peromyscus leucopus to demonstrate that sex ratio is explained by an exclusive effect of the father, and suggest a likely mechanism by which male-driven sex-ratio bias is attained. We identified a male sperm morphological marker that is associated with the mechanism leading to sex ratio bias; differences among males in the sperm nucleus area (a proxy for the sex chromosome that the sperm contains) explain 22% variation in litter sex ratio. We further show the role played by the sperm nucleus area as a mediator in the relationship between individual genetic variation and sex-ratio bias. Fathers with high levels of genetic variation had ejaculates with a higher proportion of sperm with small nuclei area. This, in turn, led to siring a higher proportion of sons (25% increase in sons per 0.1 decrease in the inbreeding coefficient). Our results reveal a plausible mechanism underlying unexplored male-driven sex-ratio biases. We also discuss why this pattern of paternal bias can be adaptive. This research puts to rest the idea that father contribution to sex ratio variation should be disregarded in vertebrates, and will stimulate research on evolutionary constraints to sex ratios-for example, whether fathers and mothers have divergent, coinciding, or neutral sex allocation interests. Finally, these results offer a potential explanation for those intriguing cases in which there are sex ratio biases, such as in humans. © 2017 The Author(s).

A Study on the Effects of Compression Ratio, Engine Speed and Equivalence Ratio on HCCI Combustion of DME

DEFF Research Database (Denmark)

Pedersen, Troels Dyhr; Schramm, Jesper

2007-01-01

An experimental study has been carried out on the homogeneous charge compression ignition (HCCI) combustion of Dimethyl Ether (DME). The study was performed as a parameter variation of engine speed and compression ratio on excess air ratios of approximately 2.5, 3 and 4. The compression ratio was...

Eccentric crank variable compression ratio mechanism

Science.gov (United States)

Lawrence, Keith Edward [Kobe, JP; Moser, William Elliott [Peoria, IL; Roozenboom, Stephan Donald [Washington, IL; Knox, Kevin Jay [Peoria, IL

2008-05-13

A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

Pengaruh Debt to Equty Ratio, Current Ratio , Net Profit Margin Terhadap Harga Saham dengan Price Earning Ratio Sebagai Variabel Pemoderasi pada Perusahaan Manufaktur yang Terdaftar di BEI Periode 2012-2014

OpenAIRE

Theresia, Paskah Lia

2017-01-01

This study conducted to analyze the effect of variable Debt to Equity Ratio (DER), Current Ratio (CR), Net Profit Margin (NPM) andPrice Earnings Ratio (PER) to the Stock Prices with Price Earnings Ratio (PER) as an moderating variable on companies listed on Indonesian Stock Exchange from 2012 - 2014.The samplingtechnique used is purposive sampling and number of samples used by 23 companies. The analysis technique used are Descriptive Statistic Analysis, Classical Assumption Test, Hypothesis T...

Combined slope ratio analysis and linear-subtraction: An extension of the Pearce ratio method

Science.gov (United States)

De Waal, Sybrand A.

1996-07-01

A new technique, called combined slope ratio analysis, has been developed by extending the Pearce element ratio or conserved-denominator method (Pearce, 1968) to its logical conclusions. If two stoichiometric substances are mixed and certain chemical components are uniquely contained in either one of the two mixing substances, then by treating these unique components as conserved, the composition of the substance not containing the relevant component can be accurately calculated within the limits allowed by analytical and geological error. The calculated composition can then be subjected to rigorous statistical testing using the linear-subtraction method recently advanced by Woronow (1994). Application of combined slope ratio analysis to the rocks of the Uwekahuna Laccolith, Hawaii, USA, and the lavas of the 1959-summit eruption of Kilauea Volcano, Hawaii, USA, yields results that are consistent with field observations.

Comparing computing formulas for estimating concentration ratios

International Nuclear Information System (INIS)

Gilbert, R.O.; Simpson, J.C.

1984-03-01

This paper provides guidance on the choice of computing formulas (estimators) for estimating concentration ratios and other ratio-type measures of radionuclides and other environmental contaminant transfers between ecosystem components. Mathematical expressions for the expected value of three commonly used estimators (arithmetic mean of ratios, geometric mean of ratios, and the ratio of means) are obtained when the multivariate lognormal distribution is assumed. These expressions are used to explain why these estimators will not in general give the same estimate of the average concentration ratio. They illustrate that the magnitude of the discrepancies depends on the magnitude of measurement biases, and on the variances and correlations associated with spatial heterogeneity and measurement errors. This paper also reports on a computer simulation study that compares the accuracy of eight computing formulas for estimating a ratio relationship that is constant over time and/or space. Statistical models appropriate for both controlled spiking experiments and observational field studies for either normal or lognormal distributions are considered. 24 references, 15 figures, 7 tables

Hubungan Analisis Ratio Keuangan dengan Kesehatan Perusahaan

Directory of Open Access Journals (Sweden)

Soekarso Soekarso

2009-09-01

Full Text Available In the business world, companies develop a vision and mission to improve welfare in the future. The work program the company is to achieve productivity and profitability. Finance in the company is one of the strategic functions that includes wealth management and transformation of added value (added value and also the control of corporate health. The financial statements such as balance sheet (balance sheet, profit and loss statement (income statement, and financial ratio (financial ratios, reflects the company's performance and health. Financial ratio analysis relates to the health of the company through a ratio of effectiveness, efficiency, productivity, profitability, liquidity, and solvability. Analysis shows that whenever actual value of financial ratios is above standard it means the company is healthy, and when the actual value of financial ratios is below the standard, it reversely means that companies are not healthy.

Could changes in reported sex ratios at birth during China's 1958-1961 famine support the adaptive sex ratio adjustment hypothesis?

Directory of Open Access Journals (Sweden)

Anna Reimondos

2013-10-01

Full Text Available Background: The adaptive sex ratio adjustment hypothesis suggests that when mothers are in poor conditions the sex ratio of their offspring will be biased towards females. Major famines provide opportunities for testing this hypothesis because they lead to the widespread deterioration of living conditions in the affected population. Objective: This study examines changes in sex ratio at birth before, during, and after China's 1958-1961 famine, to see whether they provide any support for the adaptive sex ratio adjustment hypothesis. Methods: We use descriptive statistics to analyse data collected by both China's 1982 and 1988 fertility sample surveys and examine changes in sex ratio at birth in recent history. In addition, we examine the effectiveness of using different methods to model changes in sex ratio at birth and compare their differences. Results: During China's 1958-1961 famine, reported sex ratio at birth remained notably higher than that observed in most countries in the world. The timing of the decline in sex ratio at birth did not coincide with the timing of the famine. After the famine, although living conditions were considerably improved, the sex ratio at birth was not higher but lower than that recorded during the famine. Conclusions: The analysis of the data collected by the two fertility surveys has found no evidence that changes in sex ratio at birth during China's 1958-1961 famine and the post-famine period supported the adaptive sex ratio adjustment hypothesis.

Relationships between breath ratios, spirituality and health ...

African Journals Online (AJOL)

The aim of this retrospective, quantitative study was to investigate relationships between breath ratios, spirituality perceptions and health perceptions, with special reference to breath ratios that best predict optimal health and spirituality. Significant negative correlations were found between breath ratios and spirituality ...

Why is digit ratio correlated to sports performance?

Science.gov (United States)

Kim, Tae Beom; Kim, Khae Hawn

2016-12-01

Second to fourth digit ratio is the ratio of second to fourth digit length. It has been known that digit ratio is sexually dimorphic in humans, such that males tend to have lower digit ratio (longer fourth digits relative to second digits) than females. Digit ratio is thought to be a biomarker of the balance between fetal testosterone (FT) and fetal estrogen (FE) in a relatively narrow developmental window at the end of the first trimester of pregnancy. On the contrary, the relationships between digit ratio and levels of sex steroids in adults are not clear. Most correlational studies between digit ratio and adult sex steroids have revealed that this association is statistically not significant. However, for many years, a lot of researches showed negative relationships between digit ratio and sports performance such as rugby, surfing, rowing, sprinting, endurance, and hand grip strength. Here, we discuss possible mechanisms about the relationships between digit ratio and sports performance.

Introducing optional reserve ratios in Hungary

OpenAIRE

Lóránt Varga

2010-01-01

As of the reserve maintenance period commencing in November 2010, Hungarian credit institutions will be free to decide whether to apply the previously valid 2% reserve ratio, or to apply a higher mandatory reserve ratio. Credit institutions required to hold reserves may select from reserve ratios of 2, 3, 4 and 5%, and may change their decision on a semi-annual basis. In line with the international best practice, the purpose of the MNB’s reserve requirement system is to support credit institu...

Optimized aspect ratios of restrained thick-wall cylinders by virtue of Poisson's ratio selection. Part two: Temperature application

International Nuclear Information System (INIS)

Whitty, J.P.M.; Henderson, B.; Francis, J.

2011-01-01

Highlights: → Incontrovertible evidence is presented that thermal stresses in cylindrical components which include nuclear reactors and containment vessels are shown to be highly dependent on the Poisson's ratio of the materials. → The key novelty is concerned with the identification of a new potential thermal applications for negative Poisson's ratio (auxetic) materials; i.e. those that get fatter when they are stretched. → Negative Poisson's ratio (auxetic) materials exhibit lower thermal stress build-up than conventional positive Poisson's ratio materials, this conjecture being proven using thermal surface plots. - Abstract: Analytical and numerical modelling have been employed to show that the choice of Poisson's ratio is one of the principal design criteria in order to reduce thermal stress build-up in isotropic materials. The modelling procedures are all twofold; consisting of a solution to a steady-state heat conduction problem followed by a linear static solution. The models developed take the form of simplistic thick-wall cylinders such model systems are applicable at macro-structural and micro-structural levels as the underlining formulations are based on the classical theory of elasticity. Generally, the results show that the Poisson's ratio of the material has a greater effect on the magnitude of the principal stresses than the aspect ratio of the cylinders investigated. Constraining the outside of these models significantly increases the thermal stresses induced. The most significant and original finding presented is that the for both freely expanding and constrained thick-wall cylinders the optimum Poisson's ratio is minus unity.

Independent isomer yield ratio of 90Rb

International Nuclear Information System (INIS)

Reeder, P.L.; Warner, R.A.; Ford, G.P.; Willmes, H.

1985-05-01

The independent isomer yield ratio for 90 Rb from thermal neutron fission of 235 U has been measured by use of a new technique involving a pulsed reactor and an on-line mass spectrometer facility. The apparent isomer yield ratio was measured for different ion collection time intervals and extrapolated to zero collection time to eliminate interference from 90 Kr decay. The observed isomer yield ratio of 8.7 +- 1.0 is one of the largest ratios measured for a low energy fission process. However, a statistical model analysis shows that the average angular momentum ( = 4.5) deduced from this isomer yield ratio is consistent with average angular momentum for other products from low energy fission. 7 refs

D/H ratio for Jupiter

International Nuclear Information System (INIS)

Smith, H.; Schempp, W.V.; Baines, K.H.

1989-01-01

Observations of Jupiter's spectrum near the R5(0) HD line at 6063.88 A are reported. A feature with an equivalent width of 0.065 + or - 0.021 mA is coincident with the expected line. This feature is compared with HD profiles computed for inhomogeneous scattering models for Jupiter to yield a range for the Jovian D/H ratio of 1.0-2.9 x 10 to the -5th. This D/H ratio is in the lower range of previously reported D/H values for Jupiter and corresponds to an essentially solar D/H ratio for Jupiter. The detection of HD features in the presence of probable blends with spectral features of minor atmospheric hydrocarbon molecules is discussed. Such blends may make unambiguous identification of HD features difficult. 26 references

Quantitative structure activity relationships (QSAR) for binary mixtures at non-equitoxic ratios based on toxic ratios-effects curves.

Science.gov (United States)

Tian, Dayong; Lin, Zhifen; Yin, Daqiang

2013-01-01

The present study proposed a QSAR model to predict joint effects at non-equitoxic ratios for binary mixtures containing reactive toxicants, cyanogenic compounds and aldehydes. Toxicity of single and binary mixtures was measured by quantifying the decrease in light emission from the Photobacterium phosphoreum for 15 min. The joint effects of binary mixtures (TU sum) can thus be obtained. The results showed that the relationships between toxic ratios of the individual chemicals and their joint effects can be described by normal distribution function. Based on normal distribution equations, the joint effects of binary mixtures at non-equitoxic ratios ( [Formula: see text]) can be predicted quantitatively using the joint effects at equitoxic ratios ( [Formula: see text]). Combined with a QSAR model of [Formula: see text]in our previous work, a novel QSAR model can be proposed to predict the joint effects of mixtures at non-equitoxic ratios ( [Formula: see text]). The proposed model has been validated using additional mixtures other than the one used for the development of the model. Predicted and observed results were similar (p>0.05). This study provides an approach to the prediction of joint effects for binary mixtures at non-equitoxic ratios.

Pengaruh Likuiditas, Profitabilitas, Leverage, dan Market Ratio terhadap Dividend Payout Ratio pada Perusahaan Manufaktur

Directory of Open Access Journals (Sweden)

Erna Puspita

2017-04-01

Full Text Available Dividend policy is concerned with financial policies regarding what amount cash dividend paid to shareholders and re-invested as retained earnings. The recent research aimed to test empirically various factors is considered to affect dividend policy. The independent variables in his research included Current Ratio (CR, Return on Equity (ROE, Debt to Equity Ratio (DER, and Earning Per Share (EPS. Meanwhile, the dependent variable was Dividend Payout Ratio (DPR. Quantitative research was used as the research design and the data was secondary data. Furthermore, purposive sampling was selected to get the sample. The result was 14 companies that pay dividend continuously during this research conducted on 2012 - 2014 were selected as the sample of this research. Multiple linier regression was used to analyze the data. The results showed that ROE and EPS has a contribution to the DPR, and then CR and DER has no contribution to the DPR.

A Librarian's Primer on Financial Ratios.

Science.gov (United States)

Kerbel, Sandra Sandor

1982-01-01

Explains in simple terms the nature and function of a number of basic types of business and industrial financial ratios. An annotated list of five basic sources for ratios is included and a reference list and bibliography are attached. (JL)

Geometrical scaling in charm structure function ratios

International Nuclear Information System (INIS)

Boroun, G.R.; Rezaei, B.

2014-01-01

By using a Laplace-transform technique, we solve the next-to-leading-order master equation for charm production and derive a compact formula for the ratio R c =F L cc ¯ /F 2 cc ¯ , which is useful for extracting the charm structure function from the reduced charm cross section, in particular, at DESY HERA, at small x. Our results show that this ratio is independent of x at small x. In this method of determining the ratios, we apply geometrical scaling in charm production in deep inelastic scattering (DIS). Our analysis shows that the renormalization scales have a sizable impact on the ratio R c at high Q 2 . Our results for the ratio of the charm structure functions are in a good agreement with some phenomenological models

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

Science.gov (United States)

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.

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

Science.gov (United States)

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

DC-to-AC inverter ratio failure detector

Science.gov (United States)

Ebersole, T. J.; Andrews, R. E.

1975-01-01

Failure detection technique is based upon input-output ratios, which is independent of inverter loading. Since inverter has fixed relationship between V-in/V-out and I-in/I-out, failure detection criteria are based on this ratio, which is simply inverter transformer turns ratio, K, equal to primary turns divided by secondary turns.

7 CFR 1425.10 - Financial ratio requirement.

Science.gov (United States)

2010-01-01

... 7 Agriculture 10 2010-01-01 2010-01-01 false Financial ratio requirement. 1425.10 Section 1425.10... Financial ratio requirement. To be financially able to make advances to their members and to market their commodities, CMA's shall have a current ratio of at least 1 dollar of current assets for each 1 dollar of...

Do Strontium Isotope Ratios of Animal Bone and Teeth Really Reflect the Isotope Ratios of its birth- and growth-places?

Science.gov (United States)

Minami, M.; Goto, A.; Suzuki, K.; Kato, T.; Watanabe, K.; Hasegawa, T.

2007-12-01

Strontium enters the human body through the food chain as nutrients pass from bedrock through soil and water to plants and animals. Strontium substitutes for calcium in the hydroxyapatite mineral of skeletal tissue, and is stored there. 87Sr/86Sr ratios in an individual's bone and teeth could directly reflect the isotopic ratios found in the plants and animals that she or he consumed, which reflect the isotope ratios found in the soil and bedrock of that geologic region. Therefore, 87Sr/86Sr ratios of human skeletons could be useful tools for assessing human residential mobility in prehistory, and many studies on them have been often made. In this study, to evaluate whether the 87Sr/86Sr ratio of a bone or teeth really reflects the isotopic ratios of its birth and growth places, several bone and teeth samples were measured for 87Sr/86Sr ratios, compared with 87Sr/86Sr ratios of geological samples in their growth-places. Bone and teeth samples were leached with 5% acetic acid. After drying, samples were ashed in a muffle furnace at 825°C for 8h, and then digested in nitric acid, followed by cation exchange chromatography with 2.4M hydrochloric acid. 87Sr/86Sr ratios were measured using a thermal ionization mass Spectrometer (VG Sector 54) or an inductively coupled plasma mass spectrometer (Finnigan ELEMENT2). A modern boar bone collected at Asuke, Toyota City, Aichi prefecture, Japan showed a 87Sr/86Sr of 0.71001±0.00002 (2 σ), while stream sediments in the Asuke area showed around 0.710 (Asahara et al., 2006). The 87Sr/86Sr ratio of a modern black bass bone collected from Lake Biwa, Shiga prefecture, Japan was 0.71215±0.00002, while those of surface water in Lake Biwa was 0.71233±0.00002. The similar 87Sr/86Sr ratios between bone and its provenance geology could indicate that the 87Sr/86Sr ratios of bones reflect the isotopic ratios of the birth- and growth-places. The more results of modern and fossil skeletons will be shown in our presentation.

Isotopic ratios in the solar system

International Nuclear Information System (INIS)

1985-01-01

This colloquium is aimed at presentation of isotope ratio measurements in different objects of solar system and surrounding interstellar space and evaluation of what information on composition and structure of primitive solar nebula and on chemical evolution of interstellar space in this part of the galaxy can be deduced from it. Isotope ratio in solar system got from laboratory study of extraterrestrial materials is a subject of this colloquium. Then isotope ratio measured in solar wind, planets and comets. Measurements either are made in-situ by mass spectrometry of ions in solar wind or planetery atmosphere gases either are remote measurements of spectra emitted by giant planets and comets. At last, planetology and astrophysics implications are presented and reviewed. Consraints for solar system formation model can be deduced from isotope ratio measurement. Particularly, isotope anomalies are marks of the processes, which have influenced the primitive solar nebula contraction [fr

Contribution to the problem of liquidity ratios

OpenAIRE

Dvoøáèek Jaroslav

1997-01-01

The article is based on the importance of the financial analysis in mining industry. The author pays attention to liquidity ratios given in literature from the standpoint of their number, content, units and recommended quantity value of single ratios. For the application in practice two liquidity ratios are suggested and the methodology of their recommended values determination is given.

FINANCIAL RATIOS – REVEAL HOW A BUSINESS IS DOING?

OpenAIRE

MIRELA MONEA

2009-01-01

The paper aims to present the main financial ratios which provide a picture about company’s profitability, its financial position, use of its assets efficiency, its long-term debt financing. Discussion is focused on: profitability ratios, short-term financial ratios, activity ratios, long-term debt ratios or dividend policy ratios. Also, will try to answer at the following main questions: What financial ratios analysis tells us? What the users of these needs to know?

Curious Sex Ratios and Cytoplasmic Genes

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. Curious Sex Ratios and Cytoplasmic Genes Microbes Can Distort the Sex Ratio of Populations. Stephen J Freeland Laurence D Hurst. General Article Volume 2 Issue 6 June 1997 pp 68-78 ...

Limiting density ratios in piston-driven compressions

International Nuclear Information System (INIS)

Lee, S.

1985-07-01

By using global energy and pressure balance applied to a shock model it is shown that for a piston-driven fast compression, the maximum compression ratio is not dependent on the absolute magnitude of the piston power, but rather on the power pulse shape. Specific cases are considered and a maximum density compression ratio of 27 is obtained for a square-pulse power compressing a spherical pellet with specific heat ratio of 5/3. Double pulsing enhances the density compression ratio to 1750 in the case of linearly rising compression pulses. Using this method further enhancement by multiple pulsing becomes obvious. (author)

Golden ratio beauty as scientific function

Directory of Open Access Journals (Sweden)

Scott A. Olsen

2018-01-01

Full Text Available Normally when one is considering the golden ratio in the history of ideas, one is often looking at it as an aesthetic principle – usually associated with Greek art, sculpture and mathematics. However, in recent years the prevalence of the golden ratio within a broad range of scientific disciplines has brought its role in the perfection of science to the forefront. I would like to collapse these two areas by proposing a somewhat novel way of looking at the aesthetics of the golden ratio: its pervasive expression in scientific form and function is the basis of the aesthetics in the world. Therefore, science contains the same mathematical beauty as found in artistic expression. The golden ratio guides the Chaos Border of Kolmogorov, Arnold, and Moser (KAM theorem and it can be found hidden in all elementary particles, and even in the proportions of dark matter and energy relative to visible matter and energy. It is evident in the structure and growth functions of plants and animals and it can be found in the physiological functions of humans. It now appears that without the golden ratio, we would not have the form or function of the proton, cell, athlete, horse, species, planet, solar system or galaxy.

Global Carbon Reservoir Oxidative Ratios

Science.gov (United States)

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.

Investigation of Pockels Cells Crystal Contrast Ratio Distribution

Directory of Open Access Journals (Sweden)

Giedrius Sinkevičius

2017-07-01

Full Text Available The BBO Pockel’s cell has been investigated. The investigation results of optimal operating area on the surface of the crystal dependent of intrinsic contrast ratio (ICR and voltage contrast ratio (VCR for Pockel’s cell are presented. The block diagram of Pockel’s cells contrast measurement stand and measurement methodology are introduced and discussed. The graphs of intrinsic contrast ratio distribution on crystal surface, contrast ratio with voltage dependency and voltage contrast ratio distribution on crystal surface with half-wave voltage are presented.

Contribution to the problem of liquidity ratios

Directory of Open Access Journals (Sweden)

Dvoøáèek Jaroslav

1997-03-01

Full Text Available The article is based on the importance of the financial analysis in mining industry. The author pays attention to liquidity ratios given in literature from the standpoint of their number, content, units and recommended quantity value of single ratios. For the application in practice two liquidity ratios are suggested and the methodology of their recommended values determination is given.

Financial Ratio Analysis Comes to Nonprofits.

Science.gov (United States)

Chabotar, Kent John

1989-01-01

To evaluate their financial health, a growing number of colleges, universities, and other nonprofit organizations are using financial ratio analysis, a technique used in business. The strengths and weaknesses of ratio analysis are assessed and suggestions are made on how nonprofits can use it most effectively. (Author/MLW)

Serial binary interval ratios improve rhythm reproduction

Directory of Open Access Journals (Sweden)

Xiang eWu

2013-08-01

Full Text Available Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8, non-binary integer (1:3:5:6, and non-integer (1:2.3:5.3:6.4 ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

Serial binary interval ratios improve rhythm reproduction.

Science.gov (United States)

Wu, Xiang; Westanmo, Anders; Zhou, Liang; Pan, Junhao

2013-01-01

Musical rhythm perception is a natural human ability that involves complex cognitive processes. Rhythm refers to the organization of events in time, and musical rhythms have an underlying hierarchical metrical structure. The metrical structure induces the feeling of a beat and the extent to which a rhythm induces the feeling of a beat is referred to as its metrical strength. Binary ratios are the most frequent interval ratio in musical rhythms. Rhythms with hierarchical binary ratios are better discriminated and reproduced than rhythms with hierarchical non-binary ratios. However, it remains unclear whether a superiority of serial binary over non-binary ratios in rhythm perception and reproduction exists. In addition, how different types of serial ratios influence the metrical strength of rhythms remains to be elucidated. The present study investigated serial binary vs. non-binary ratios in a reproduction task. Rhythms formed with exclusively binary (1:2:4:8), non-binary integer (1:3:5:6), and non-integer (1:2.3:5.3:6.4) ratios were examined within a constant meter. The results showed that the 1:2:4:8 rhythm type was more accurately reproduced than the 1:3:5:6 and 1:2.3:5.3:6.4 rhythm types, and the 1:2.3:5.3:6.4 rhythm type was more accurately reproduced than the 1:3:5:6 rhythm type. Further analyses showed that reproduction performance was better predicted by the distribution pattern of event occurrences within an inter-beat interval, than by the coincidence of events with beats, or the magnitude and complexity of interval ratios. Whereas rhythm theories and empirical data emphasize the role of the coincidence of events with beats in determining metrical strength and predicting rhythm performance, the present results suggest that rhythm processing may be better understood when the distribution pattern of event occurrences is taken into account. These results provide new insights into the mechanisms underlining musical rhythm perception.

Ultima Ratio as a Constitutional Principle

Directory of Open Access Journals (Sweden)

Kaarlo Tuori

2013-01-01

Full Text Available The paper argues the criminal law notion of ultima ratio is an instance of a broader constitutional law principle of proportionality. However, ultima ratio is not the only principle relevant in a constitutional assessment of criminalization. The role of ultima ratio is to impose limitations on criminalization. But constitutional doctrines also exist which call for criminalization and might even be seen as establishing a criminalization obligation. The paper examines three constitutional counter weights to ultima ratio. The first of these is discussed in the context of state constitutions. This is the cluster of the interrelated constitutional doctrines of the horizontal effect of fundamental rights and the protective duty of the state, as well as the understanding of collective security as a basic right. These doctrines are analysed in the light of the praxis of the German Constitutional Court and the Finnish Constitutional Law Committee. The two other constitutional counterweights are discussed at the level of the transnational, European constitution. These are the principles of precaution and effectiveness. Este artículo defiende que el concepto de ultima ratio es una instancia más amplia del principio de proporcionalidad dentro del derecho constitucional. Sin embargo, el ultima ratio no es el único principio relevante en la valoración constitucional de la criminalización. El papel del ultima ratio es imponer límites a la criminalización. Pero también existen doctrinas constitucionales que exigen la criminalización e incluso dan pie a entender que obligan a establecer una pena. El documento examina tres contrapesos constitucionales al ultima ratio. En primer lugar, se analiza en el contexto de las constituciones estatales. Este es el conjunto de las doctrinas constitucionales interrelacionadas entre el efecto horizontal de los derechos fundamentales y el deber de protección del Estado, así como la asunción de la seguridad colectiva

The role of B/D ratio and A/D ratio to defferentiate malignancy from benignancy in distal extrahepatic bile duct obstruction

International Nuclear Information System (INIS)

Rhim, Hyun Chul; Baek, JUng Hwan; Jeon, Eui Yong; Koh, Byung Hee; Cho, On Koo; Kim, Young Hwan

1994-01-01

To determine wheter bilirubin/extrahepatic bile duct diameter ratio(B/D ratio) or alkalinephosphatase/extrahepatic bile duct diameter ratio (A/D ratio) can be used to differentiate malignant from benigndisease in distal extrahepatic bile duct obstruction during ultrasonographic examination. We retrospectively reviewed the sonograms and laboratory data of 100 patients with obstructive jaundice (benign : n=50, malignant: : n=50). The diagnosis was confirmed either surgically (n=66) or clinically (n=34). The B/D ratio and A/D radio were calculated by means of dividing total bilirubin (mg/dl) and alkaline phosphatase (I.U.)respectively by maximum extrahepatic bile duct diameter(mm) on ultrasonogram. Significant difference in B/D ratio was found between the benignancy (0.28+0.25) and malignancy (0.98+0.84) groups (P<0.001). Significant difference in A/D ratio was also found between the benignancy (15.00+10.22) and malignancy (32.44+30.28) groups(P<0.001) Accuracies to predict malignancy according to criteria of B/D and A/D ratios were less than 75% and 65%respectively. On the other hand, the positive predictive value and specificity were relatively high. The B/D ratio and A/D ratio calculated from ultrasonograms can be used as a valuable screening index todifferentiate malignancy from benignacy in patients with distal extrahepatic bile duct obstruction, especially when the sonography is difficult because of the interposition of bowel gas or obesity

The adenoid-nasopharynx ratio. Its clinical value in children

International Nuclear Information System (INIS)

Zou Mingshun

1997-01-01

To evaluate the clinical usefulness of adenoid-nasopharynx ratio (A/N ratio) measured on nasopharyngeal lateral plain film, 106 clinical cases of secretory otitis media were selected to measure the A/N ratio before treatment. For patients with A/N ratio of 0.50-0.70, the symptoms improved distinctly after conservative treatment, but one half of patients with A/N ratio ≥ 0.71 required adenoidectomy. A/N ratio is a practical and convenient method for evaluation of the adenoid. A/N ratio ≥ 0.71 indicates pathological enlarged adenoid

Business sustainability performance measurement: Eco-ratio analysis

Directory of Open Access Journals (Sweden)

Collins C. Ngwakwe

2016-12-01

Full Text Available Eco-aware customers and stakeholders are demanding for a measurement that links environmental performance with other business operations. To bridge this seemingly measurement gap, this paper suggests ‘Eco-Ratio Analysis’ and proposes an approach for conducting eco-ratio analysis. It is argued that since accounting ratios function as a tool for evaluating corporate financial viability by management and investors, eco-ratio analysis should be brought to the fore to provide a succinct measurement about the linkage between environmental performance and conventional business performance. It is hoped that this suggestion will usher in a nuance debate and approach in the teaching, research and practice of environmental management and sustainability accounting

Neutrophil-lymphocyte ratio and platelet-lymphocyte ratio as predictors of wound healing failure in head and neck reconstruction.

Science.gov (United States)

Maruyama, Yoko; Inoue, Keita; Mori, Keita; Gorai, Katsuya; Shimamoto, Ryo; Onitsuka, Tetsuro; Iguchi, Hiroyoshi; Okazaki, Mutsumi; Nakagawa, Masahiro

2017-01-01

In microsurgical head and neck reconstruction, a higher rate of post-operative wound complication could be predicted by a lower pre-operative neutrophil ratio (wound complications in microsurgical head and neck reconstruction. Patients who were undergoing tumor ablation and microsurgical reconstruction from April 2011 to March 2014 were analyzed retrospectively. The pre-operative hematological data, age, sex, co-morbidities, body mass index (BMI), adjuvant therapies, smoking, operation time, blood loss, total protein, T-stage, and Anesthesiologists Performance Status (ASA-PS) score were collected. Cases of post-operative wound healing failure were reviewed. One hundred and three consecutive patients were enrolled. Among these, the results of 77 patients who were younger than 70 years of age were analyzed. The distributions of the neutrophil ratio (p = .0005), lymphocyte ratio (p = .0166), monocyte ratio (p = .0341), NLR (p = .005), and PLR (p = .008) differed significantly between the patients with and without post-operative wound healing failure. Neutrophil ratio, NLR, and PLR cut-off values of 64.9, 3.5, and 160 were significantly associated with the rate of wound healing failure rate (p = .0002, .00021, .0042, respectively).

The Golden Ratio--A Contrary Viewpoint

Science.gov (United States)

Falbo, Clement

2005-01-01

Many assertions about the occurrence of the golden ratio phi in art, architecture, and nature have been shown to be false, unsupported, or misleading. For instance, we show that the spirals found in sea shells, in particular the "Nautilus pompilius," are not in the shape of the golden ratio, as is often claimed. Some of the most interesting…

Systematic study of the π-/π+ ratio in heavy-ion collisions with the same neutron/proton ratio but different masses

International Nuclear Information System (INIS)

Zhang Ming; Xiao Zhigang; Zhu Shengjiang; Li Baoan; Chen Liewen; Yong Gaochan

2009-01-01

A systematic study of the π - /π + ratio in heavy-ion collisions with the same neutron/proton ratio but different masses can help single out effects of the nuclear mean field on pion production. Based on simulations using the IBUU04 transport model, it is found that the π - /π + ratio in head-on collisions of 48 Ca+ 48 Ca, 124 Sn+ 124 Sn, and 197 Au+ 197 Au at beam energies from 0.25 to 0.6 GeV/nucleon increases with increasing the system size or decreasing the beam energies. A comprehensive analysis of the dynamical isospin fractionation and the π - /π + ratio as well as their time evolution and spatial distributions demonstrates clearly that the π - /π + ratio is an effective probe of the high-density behavior of the nuclear symmetry energy.

Evaluation of Neutrophil–Lymphocyte Ratio, Platelet–Lymphocyte Ratio and Red Blood Cell Distribution Width–Platelet Ratio for Diagnosis of Premature Ovarian Insufficiency

Directory of Open Access Journals (Sweden)

Gülşah Ilhan

2017-03-01

Full Text Available Objective: To evaluate whether systemic inflammatory markers (neutrophil to lymphocyte ratio (NLR, platelet to lymphocyte ratio (PLR and red blood cell distribution width (RDW to platelet ratio (RPR can be used as reliable markers for the diagnosis of premature ovarian insufficiency (POI and to determine if there is a relationship between these markers and follicle stimulating hormone (FSH, Anti-Müllerian Hormone (AMH levels.Materials and methods: Written and electronic medical records were reviewed using searches for diagnoses with the terms of 'premature ovarian failure', 'premature ovarian insufficiency'. Patients younger than the age of 40 were diagnosed to have premature ovarian insufficiency based on their menstrual history and sonographic examination and they were compared with healthy females. Complete blood counts, day-3 hormone profiles, AMH levels of all subjects were analyzed.Results: NLR was statistically higher in POI group compared with controls (p < 0.05. NLR had a positive correlation between FSH (r = 0.23, p = 0.045 and a negative association with AMH (r = - 0.27, p = 0.018. The area under ROC curve for NLR in POI was 0.66, with a threshold value 1.5 and sensitivity = 75.7 % and specificity = 46.0 %.Conclusion: NLR can be a marker for the diagnosis of POI. There is a close relationship between NLR and ovarian reserve markers such as FSH and AMH.

La Dinámica Cross-Section de los Ratios Financieros: ¿Tienden los Ratios a Converger hacia la Media Sectorial?

Directory of Open Access Journals (Sweden)

Manuel Illueca Muñoz

2002-12-01

Full Text Available El objetivo fundamental de este artículo consiste en contrastar si los ratios financieros describen un proceso de ajuste / convergencia hacia la media sectorial. Utilizando un enfoque no paramétrico, se ha modelizado explícitamente la dinámica de las distribuciones de seis ratios, calculados a partir de una muestra de empresas del sector español de pavimentos y revestimientos cerámicos. Los resultados no permiten afirmar que las empresas de la muestra converjan hacia la media del sector, al contrario, las distribuciones de probabilidad de los ratios analizados presentan a largo plazo una dispersión similar a la del periodo muestral.The main objective of this paper is to test whether financial ratios follow a convergent path towards the industry mean. A non parametric approach is used to model the cross-section dynamics of six financial ratios, computed on a sample of Spanish tile firms. Our findings do not support the hipothesis of convergence. The dispersion of the ratios does not shrink in the long term.

A ratio scale for brightness perception derived from difference and ratio judgments

NARCIS (Netherlands)

Ridder, de H.; Sabourin, M.

1992-01-01

The often observed nonlinearity between magnitude estimations and category ratings has raised the question whether subjects can judge sensation differences as well as sensation ratios when instructed to do so. For brightness this will be shown to be the case; the rank order of difference judgments

Determination of Optimum Compression Ratio: A Tribological Aspect

Directory of Open Access Journals (Sweden)

L. Yüksek

2013-12-01

Full Text Available Internal combustion engines are the primary energy conversion machines both in industry and transportation. Modern technologies are being implemented to engines to fulfill today's low fuel consumption demand. Friction energy consumed by the rubbing parts of the engines are becoming an important parameter for higher fuel efficiency. Rate of friction loss is primarily affected by sliding speed and the load acting upon rubbing surfaces. Compression ratio is the main parameter that increases the peak cylinder pressure and hence normal load on components. Aim of this study is to investigate the effect of compression ratio on total friction loss of a diesel engine. A variable compression ratio diesel engine was operated at four different compression ratios which were "12.96", "15:59", "18:03", "20:17". Brake power and speed was kept constant at predefined value while measuring the in- cylinder pressure. Friction mean effective pressure ( FMEP data were obtained from the in cylinder pressure curves for each compression ratio. Ratio of friction power to indicated power of the engine was increased from 22.83% to 37.06% with varying compression ratio from 12.96 to 20:17. Considering the thermal efficiency , FMEP and maximum in- cylinder pressure optimum compression ratio interval of the test engine was determined as 18.8 ÷ 19.6.

Elevated Neutrophil Lymphocyte Ratio in Recurrent Optic Neuritis

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Hande Guclu

2015-01-01

Full Text Available Purpose. To demonstrate the relation between optic neuritis (ON and systemic inflammation markers as neutrophil lymphocyte ratio (N/L ratio, platelet count, mean platelet volume (MPV, and red cell distribution width (RDW and furthermore to evaluate the utilization of these markers to predict the frequency of the ON episodes. Methods. Forty-two patients with acute ON and forty healthy subjects were enrolled into the study. The medical records were reviewed for age, sex, hemoglobin (Hb, Haematocrit (Htc, RDW, platelet count, MPV, white blood cell count (WBC, neutrophil and lymphocyte count, and neutrophil lymphocyte ratio (N/L ratio. Results. The mean N/L ratio, platelet counts, and RDW were significantly higher in ON group (p=0.000, p=0.048, and p=0.002. There was a significant relation between N/L ratio and number of episodes (r=0.492, p=0.001. There was a statistically significant difference for MPV between one episode group and recurrent ON group (p=0.035. Conclusions. Simple and inexpensive laboratory methods could help us show systemic inflammation and monitor ON patients. Higher N/L ratio can be a useful marker for predicting recurrent attacks.

Determinants of capital adequacy ratio in Kuwaiti banks

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Moeidh Alajmi

2015-10-01

Full Text Available The aim of this study is to identify the effects of seven internal factors of five conventional Kuwaiti banks on capital adequacy ratio (CAR. The five factors are: Loans to Assets, Loans to Deposits, Non-Performing Loans to Total Loans, Return on Assets, Return on Equity, Dividend Payout and Total Liability to Total Assets. The study covers the period from 2005 to 2013. The study shows that under fixed effect model, variables DIVIEDEND, LAR, LDR, NPLLR, and ROE do not have any impact on capital adequacy ratio. However, SIZE has a significant and negative relationship with capital adequacy ratio. Also, ROA shows a significant and negative relationship with capital adequacy ratio. Under random effect model, results indicate that CAR is adversely affected by bank’s SIZE (total liability to assets, and ROA has a significant and negative relationship with capital adequacy ratio, However, Loan to Deposit Ratio (LDR showed a significant and positive relationship with capital adequacy ratio. On the other hand, dividend payout, loans to assets, Non-Performing Loans to Total Loans and Return on equity do not have significant effect on CAR under random effect model.

Intake to Production Ratio

DEFF Research Database (Denmark)

Nazaroff, William; Weschler, Charles J.; Little, John C.

2012-01-01

BACKGROUND: Limited data are available to assess human exposure to thousands of chemicals currently in commerce. Information that relates human intake of a chemical to its production and use can help inform understanding of mechanisms and pathways that control exposure and support efforts...... to protect public health.OBJECTIVES: We introduce the intake-to-production ratio (IPR) as an economy-wide quantitative indicator of the extent to which chemical production results in human exposure.METHODS: The IPR was evaluated as the ratio of two terms: aggregate rate of chemical uptake in a human......(n-butyl) phthalate, 1,040 ppm for para-dichlorobenzene, 6,800 ppm for di(isobutyl) phthalate, 7,700 ppm for diethyl phthalate, and 8,000-24,000 ppm (range) for triclosan.CONCLUSION: The IPR is well suited as an aggregate metric of exposure intensity for characterizing population-level exposure to synthesized...

Envera Variable Compression Ratio Engine

Energy Technology Data Exchange (ETDEWEB)

Charles Mendler

2011-03-15

Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low

Impact of Inflation Accounting Application on Key Financial Ratios

Directory of Open Access Journals (Sweden)

Aydın KARAPINAR

2012-03-01

Full Text Available This paper investigates the impact of inflation accounting on key financal ratios. To this end, the financial statements of 132 companies listed in the Istanbul Stock Exchange (ISE are studied. An analyis of paired samples t test has been conducted on the financial ratios of the companies. The results show that a significant difference between adjusted cost based financial ratios and historical cost based financial ratios occurs only for current, ratios, equity ratios and noncurrent turnover ratios. The study does not cover companies operating in the financial sector. The companies reporting in accordance with IFRS for the studied periods that spans 2001-2004 are not included in the study either. The study offers valuable information as to analysing companies operating in hiper inflation economies.

Incentive Ratios of Fisher Markets

DEFF Research Database (Denmark)

Chen, Ning; Deng, Xuaitue; Zhang, Hongyang

2012-01-01

In a Fisher market, a market maker sells m items to n potential buyers. The buyers submit their utility functions and money endowments to the market maker, who, upon receiving submitted information, derives market equilibrium prices and allocations of its items. While agents may benefit...... by misreporting their private information, we show that the percentage of improvement by a unilateral strategic play, called incentive ratio, is rather limited—it is less than 2 for linear markets and at most $e^{1/e}\\thickapprox 1.445$ for Cobb-Douglas markets. We further prove that both ratios are tight....

[Using log-binomial model for estimating the prevalence ratio].

Science.gov (United States)

Ye, Rong; Gao, Yan-hui; Yang, Yi; Chen, Yue

2010-05-01

To estimate the prevalence ratios, using a log-binomial model with or without continuous covariates. Prevalence ratios for individuals' attitude towards smoking-ban legislation associated with smoking status, estimated by using a log-binomial model were compared with odds ratios estimated by logistic regression model. In the log-binomial modeling, maximum likelihood method was used when there were no continuous covariates and COPY approach was used if the model did not converge, for example due to the existence of continuous covariates. We examined the association between individuals' attitude towards smoking-ban legislation and smoking status in men and women. Prevalence ratio and odds ratio estimation provided similar results for the association in women since smoking was not common. In men however, the odds ratio estimates were markedly larger than the prevalence ratios due to a higher prevalence of outcome. The log-binomial model did not converge when age was included as a continuous covariate and COPY method was used to deal with the situation. All analysis was performed by SAS. Prevalence ratio seemed to better measure the association than odds ratio when prevalence is high. SAS programs were provided to calculate the prevalence ratios with or without continuous covariates in the log-binomial regression analysis.

Particle ratios, quarks, and Chao-Yang statistics

Energy Technology Data Exchange (ETDEWEB)

Chew, C K; Low, G B; Lo, S Y [Nanyang Univ. (Singapore). Dept. of Physics; Phua, K K [Argonne National Lab., IL (USA)

1980-01-01

By introducing quarks into Chao-Yang statistics for 'violent' collisions, particle ratios are obtained which are consistent with the Chao-Yang results. The present method can also be extended to baryon-meson and baryon-antibaryon ratios.

Sex ratios at birth after induced abortion.

Science.gov (United States)

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.

A study on the effect of free cash flow and profitability current ratio on dividend payout ratio: Evidence from Tehran Stock Exchange

Directory of Open Access Journals (Sweden)

Hosein Parsian

2014-01-01

Full Text Available Decision making about dividend payout is one of the most important decision that companies should encounter. Identifying factors that influence dividends can help managers in making an appropriate dividend policy. In the other side, companies’ dividend payouts over time and with a stable manner may influence on stock price, future earnings growth and finally investor's evaluation about owners' equity. Hence, investigating the factors influencing dividend payout ratio is of high importance. In this research, we investigate the effects of various factors on dividend payout ratio of Tehran Stock Exchange (TSE listed companies. We use time series regression (panel data in order to test the hypothesis of this study. This study provides empirical evidences by choosing a sample of 102 companies over the time span of 2005-2010. The result shows that independent variables of free cash flow and profitability current ratio have negative and significant impact on dividend payout ratio; whereas, the independent variable of leverage ratio has a positive and significant impact on dividend payout ratio. The other independent ratio such as size of the company, growth opportunities and systematic risk do not have any significant influence on dividend payout ratio.

Temperature diagnostic line ratios of Fe XVII

International Nuclear Information System (INIS)

Raymond, J.C.; Smith, B.W.; Los Alamos National Lab., NM)

1986-01-01

Based on extensive calculations of the excitation rates of Fe XVII, four temperature-sensitive line ratios are investigated, paying special attention to the contribution of resonances to the excitation rates and to the contributions of dielectronic recombination satellites to the observed line intensities. The predictions are compared to FPCS observations of Puppis A and to Solar Maximum Mission (SMM) and SOLEX observations of the sun. Temperature-sensitive line ratios are also computed for emitting gas covering a broad temperature range. It is found that each ratio yields a differently weighted average for the temperature and that this accounts for some apparent discrepancies between the theoretical ratios and solar observations. The effects of this weighting on the Fe XVII temperature diagnostics and on the analogous Fe XXIV/Fe XXV satellite line temperature diagnostics are discussed. 27 references

Prolonged Tp-e Interval, Tp-e/QT Ratio and Tp-e/QTc Ratio in Patients with Type 2 Diabetes Mellitus

Directory of Open Access Journals (Sweden)

Alptug Tokatli

2016-03-01

Full Text Available BackgroundType 2 diabetes mellitus (T2DM is associated with increased risk of malignant ventricular arrhythmias. Cardiac electrical inhomogeneity may be the leading cause of the increased arrhythmic risk in patients with T2DM. The peak and the end of the T wave (Tp-e interval and associated Tp-e/QT ratio are promising measures of ventricular repolarization indicating transmural dispersion of repolarization. The aim of this study was to assess ventricular repolarization in patients with T2DM by using Tp-e interval, Tp-e/QT ratio and Tp-e/corrected QT interval (QTc ratio.MethodsForty-three patients with T2DM and 43 healthy control subjects, matched by gender and age, were studied. All participants underwent electrocardiography (ECG recording. PR, RR and QT intervals represents the ECG intervals. These are not abbreviations. In all literature these ECG intervals are written like in this text. Tp-e intervals were measured from 12-lead ECG. Rate QTc was calculated by using the Bazett's formula. Tp-e/QT ratio and Tp-e/QTc ratio were also calculated.ResultsMean Tp-e interval was significantly prolonged in patients with T2DM compared to controls (79.4±10.3, 66.4±8.1 ms, respectively; P<0.001. We also found significantly higher values of Tp-e/QT ratio and Tp-e/QTc ratio in patients with diabetes than controls (0.21±0.03, 0.17±0.02 and 0.19±0.02, 0.16±0.02, respectively; P<0.001. There was no difference in terms of the other ECG parameters between the groups.ConclusionTp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were prolonged in patients with T2DM. We concluded that T2DM leads to augmentation of transmural dispersion of repolarization suggesting increased risk for ventricular arrhythmogenesis.

26 CFR 26.2642-5 - Finality of inclusion ratio.

Science.gov (United States)

2010-04-01

... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Finality of inclusion ratio. 26.2642-5 Section...-5 Finality of inclusion ratio. (a) Direct skips. The inclusion ratio applicable to a direct skip...) Other GSTs. With respect to taxable distributions and taxable terminations, the inclusion ratio for a...

Transcription and the aspect ratio of DNA

DEFF Research Database (Denmark)

Olsen, Kasper Wibeck; Bohr, Jakob

2013-01-01

analysis of transcription. It is shown that under certain reasonable assumptions transcription is only possible if the aspect ratio is in the regime corresponding to further twisting. We find this constraint to be in agreement with long-established crystallographic studies of DNA.......Two separate regimes exist for the aspect ratio of DNA. A low aspect regime where DNA will twist further under strain and a high aspect regime where DNA will untwist under strain. The question of the overall geometry, i.e. the aspect ratio, of DNA is revisited from the perspective of a geometrical...

Financial Ratios and Perceived Household Financial Satisfaction

Directory of Open Access Journals (Sweden)

Scott Garrett

2013-08-01

Full Text Available This paper tests the relative strength of three objective measures of financial health (using the solvency, liquidity, and investment asset ratio in predicting a household’s subjective feeling of current financial satisfaction. Using a sample of 6,923 respondents in the 2008 Health and Retirement Study this paper presents evidence of two main findings: 1 the solvency ratio is most strongly associated with financial satisfaction levels based on a cross-sectional design and 2 changes in the investment asset ratio are most strongly associated with changes in financial satisfaction over time.

ANALISIS PENGARUH CAPITAL ADEQUACY RATIO (CAR) DAN NON PERFORMING LOAN (NPL) TERHADAP LOAN TO DEPOSIT RATIO (LDR) PADA BANK BUMN PERSERO DI INDONESIA

OpenAIRE

TANGKO, IRENE LASTRY FARDANI

2012-01-01

Non Performing Loan (NPL)Analisis Pengaruh Capital Adequacy Ratio (CAR) dan Non Performing Loan (NPL) Terhadap Loan to Deposit Ratio (LDR) Pada Bank BUMN Persero Di Indonesia Analysis ofEffect ofCapitalAdequacy Ratio (CAR) and theNon-PerformingLoan(NPL) AgainstLoanto DepositRatio (LDR) Thestate-owned bankinIndonesiaPersero Irene Lastry Fardani Tangko Otto R. Payangan Maat pono Penelitian ini bertujuan untuk menganalisis pengaruh Capital Adequacy Ratio (CAR) dan Non Performin...

Transformer ratio enhancement experiment

International Nuclear Information System (INIS)

Gai, W.; Power, J. G.; Kanareykin, A.; Neasheva, E.; Altmark, A.

2004-01-01

Recently, a multibunch scheme for efficient acceleration based on dielectric wakefield accelerator technology was outlined in J.G. Power, W. Gai, A. Kanareykin, X. Sun. PAC 2001 Proceedings, pp. 114-116, 2002. In this paper we present an experimental program for the design, development and demonstration of an Enhanced Transformer Ratio Dielectric Wakefield Accelerator (ETR-DWA). The principal goal is to increase the transformer ratio R, the parameter that characterizes the energy transfer efficiency from the accelerating structure to the accelerated electron beam. We present here an experimental design of a 13.625 GHz dielectric loaded accelerating structure, a laser multisplitter producing a ramped bunch train, and simulations of the bunch train parameters required. Experimental results of the accelerating structure bench testing and ramped pulsed train generation with the laser multisplitter are shown as well. Using beam dynamic simulations, we also obtain the focusing FODO lattice parameters

BAT AGN Spectroscopic Survey - III. An Observed Link Between AGN Eddington Ratio and Narrow-Emission-Line Ratios

Science.gov (United States)

Oh, Kyuseok; Schawinski, Kevin; Koss, Michael; Trakhtenbrot, Benny; Lamperti, Isabella; Ricci, Claudio; Mushotzky, Richard; Veilleux, Sylvain; Berney, Simon; Crenshaw, D. Michael;

10 CFR 436.21 - Savings-to-investment ratio.

Science.gov (United States)

2010-01-01

... is the ratio of the present value savings to the present value costs of an energy or water conservation measure. The numerator of the ratio is the present value of net savings in energy or water and non... conservation measure. The denominator of the ratio is the present value of the net increase in investment and...

Key financial ratios can foretell hospital closures.

Science.gov (United States)

Lynn, M L; Wertheim, P

1993-11-01

An analysis of various financial ratios sampled from open and closed hospitals shows that certain leverage, liquidity, capital efficiency, and resource availability ratios can predict hospital closure up to two years in advance of the closure with an accuracy of nearly 75 percent.

Reevaluation of the Pavlov ratio in patients with cervical myelopathy.

Science.gov (United States)

Suk, Kyung-Soo; Kim, Ki-Tack; Lee, Jung-Hee; Lee, Sang-Hun; Kim, Jin-Soo; Kim, Jin-Young

2009-03-01

This study was designed to reevaluate the effectiveness of the Pavlov ratio in patients with cervical myelopathy. We studied 107 patients who underwent open door laminoplasty for the treatment of cervical myelopathy between the C3 to C7 levels. We determined the Pavlov ratio on preoperative and postoperative cervical spine lateral radiographs, the vertebral body-to-canal ratio on sagittal reconstruction CT scans, and the vertebral body-to-cerebrospinal fluid (CSF) column ratio on T2-weighted sagittal MR images from C3 to C6. The severity of myelopathy was determined using the JOA score on both preoperative and postoperative images. The recovery rate was also calculated. The Pavlov ratio in plain radiographs from patients with myelopathy was compared with the ratio of the vertebral body to the spinal canal on CT and MRI. The average Pavlov ratio between C3 and C6 ranged from 0.71 to 0.76. On CT scan, the average vertebral body-to-canal ratio between C3 and C6 ranged from 0.62 to 0.66. On MRI, the vertebral body-to-CSF column ratio between C3 and C6 ranged between 0.53 and 0.57. A positive correlation was noted between the Pavlov ratio and the vertebral body-to-canal ratio on sagittal-reconstruction CT (correlation coefficient = 0.497-0.627, p = 0.000) and between the Pavlov ratio and the vertebral body-to-CSF column ratio on MRI (correlation coefficient = 0.511-0.649, p = 0.000). We demonstrated a good correlation between the Pavlov ratio and both the vertebral body-to-canal ratio on CT and the vertebral body-to-CSF column ratio on MRI. Therefore, the Pavlov ratio can be relied upon to predict narrowing of the cervical spinal canal in the sagittal plane.

From Fibonacci Sequence to the Golden Ratio

Directory of Open Access Journals (Sweden)

Alberto Fiorenza

2013-01-01

Full Text Available We consider the well-known characterization of the Golden ratio as limit of the ratio of consecutive terms of the Fibonacci sequence, and we give an explanation of this property in the framework of the Difference Equations Theory. We show that the Golden ratio coincides with this limit not because it is the root with maximum modulus and multiplicity of the characteristic polynomial, but, from a more general point of view, because it is the root with maximum modulus and multiplicity of a restricted set of roots, which in this special case coincides with the two roots of the characteristic polynomial. This new perspective is the heart of the characterization of the limit of ratio of consecutive terms of all linear homogeneous recurrences with constant coefficients, without any assumption on the roots of the characteristic polynomial, which may be, in particular, also complex and not real.

Disinflation in a DSGE Perspective: Sacrifice Ratio or Welfare Gain Ratio?

OpenAIRE

Guido Ascari; Tiziano Ropele

2009-01-01

When used to examine disinflation monetary policies, the current workhorse dynamic stochastic general equilibrium model of business cycle fluctuations is able to quantitatively account for the main stylized facts in terms of recessionary effects and sacrifice ratio. We complement the transitional analysis of the short-run costs with a rigorous welfare evaluation and show that, despite the long-lasting economic downturn, disinflation entails non-zero overall welfare gains.

Osmosis and Surface Area to Volume Ratio.

Science.gov (United States)

Barrett, D. R. B.

1984-01-01

Describes an experiment designed to help students understand the concepts of osmosis and surface area to volume ratio (SA:VOL). The task for students is to compare water uptake in different sizes of potato cubes and relate differences to their SA:VOL ratios. (JN)

Maternal preconception diet and the sex ratio

NARCIS (Netherlands)

Cramer, J.S.; Lumey, L.H.

2009-01-01

Temporal variations in the sex ratio or the ratio of boys over girls at birth have been widely studied and variously attributed to social changes, conditions of war, and environmental changes. Recently, Mathews, Johnson and Neil (2008) studied the direct evidence of individual pregnancies and

Novel bacterial ratio for predicting fecal age

Energy Technology Data Exchange (ETDEWEB)

Nieman, J.; Brion, G.M. [Univ. of Kentucky, Dept. of Civil Engineering, Lexington, Kentucky (United States)]. E-mail: gbrion@engr.uky.edu

2002-06-15

This study presents an extension of ongoing research into the utility of the ratio of bacterial colonies isolated on membrane filters during the total coliform test using m-Endo broth media for the prediction of fecal age. Analysis of the relative shifts in concentrations of indicator bacterial populations in Kentucky River water quality data collected from the inlet of a local water treatment plant showed a correlation between raw concentrations of atypical colonies (AC) and total coliform colonies (TC) formed on m-Endo membrane filter tests, and fecal age. Visual analysis of plant treatment records showed that low values of the AC/TC ratio were related to periods of high flow, when runoff added fresh fecal material to the river. A more detailed analysis of 2 years of Kentucky River water quality data showed the average AC/TC ratio during months with high river flow (rain) to be 3.4, rising to an average of 27.6 during months with low flow. The average AC/TC ratio during high flow months compared to that found in other studies for raw human sewage (3.9) and the ratio increased to values associated with animal impacted urban runoff (18.9) during low flow months. (author)

Mixing ratio sensor for alcohol mixed fuel

Energy Technology Data Exchange (ETDEWEB)

Miyata, Shigeru; Matsubara, Yoshihiro

1987-08-24

In order to improve the combustion efficiency of an internal combustion engine using gasoline-alcohol mixed fuel and to reduce harmful substance in its exhaust gas, it is necessary to control strictly the air-fuel ratio to be supplied and the ignition timing. In order to detect the mixing ratio of the mixed fuel, a mixing ratio sensor has so far been proposed to detect the above mixing ratio by casting a ray of light to the mixed fuel and utilizing a change of critical angle associated with the change of the composition of the fluid of the mixed fuel. However, because of the arrangement of its transparent substance in the fuel passage with the sealing material in between, this sensor invited the leakage of the fluid due to deterioration of the sealing material, etc. and its cost became high because of too many parts to be assembled. In view of the above, in order to reduce the number of parts, to lower the cost of parts and the assembling cost and to secure no fluid leakage from the fuel passage, this invention formed the above fuel passage and the above transparent substance both concerning the above mixing ratio sensor in an integrated manner using light transmitting resin. (3 figs)

Mixing ratio sensor of alcohol mixed fuel

Energy Technology Data Exchange (ETDEWEB)

Miyata, Shigeru; Matsubara, Yoshihiro

1987-08-07

In order to improve combustion efficiency of an internal combustion engine using gasoline-alcohol mixed fuel and to reduce harmful substance in its exhaust gas, it is necessary to control strictly the air-fuel ratio to be supplied and the ignition timing and change the condition of control depending upon the mixing ratio of the mixed fuel. In order to detect the mixing ratio of the mixed fuel, the above mixing ratio has so far been detected by casting a ray of light to the mixed fuel and utilizing a change of critical angle associated with the change of the composition of the fluid of the mixed fuel. However, in case when a light emitting diode is used for the light source above, two kinds of sensors are further needed. Concerning the two kinds of sensors above, this invention offers a mixing ratio sensor for the alcohol mixed fuel which can abolish a temperature sensor to detect the environmental temperature by making a single compensatory light receiving element deal with the compensation of the amount of light emission of the light emitting element due to the temperature change and the compensation of the critical angle caused by the temperature change. (6 figs)

Novel bacterial ratio for predicting fecal age

International Nuclear Information System (INIS)

Nieman, J.; Brion, G.M.

2002-01-01

This study presents an extension of ongoing research into the utility of the ratio of bacterial colonies isolated on membrane filters during the total coliform test using m-Endo broth media for the prediction of fecal age. Analysis of the relative shifts in concentrations of indicator bacterial populations in Kentucky River water quality data collected from the inlet of a local water treatment plant showed a correlation between raw concentrations of atypical colonies (AC) and total coliform colonies (TC) formed on m-Endo membrane filter tests, and fecal age. Visual analysis of plant treatment records showed that low values of the AC/TC ratio were related to periods of high flow, when runoff added fresh fecal material to the river. A more detailed analysis of 2 years of Kentucky River water quality data showed the average AC/TC ratio during months with high river flow (rain) to be 3.4, rising to an average of 27.6 during months with low flow. The average AC/TC ratio during high flow months compared to that found in other studies for raw human sewage (3.9) and the ratio increased to values associated with animal impacted urban runoff (18.9) during low flow months. (author)

Isotope ratios of lead as pollutant source indicators

International Nuclear Information System (INIS)

Chow, T.J.; Snyder, C.B.; Earal, J.L.

1975-01-01

Each lead ore deposit has its characteristic isotope ratios which are fixed during mineral ore genesis, and this unique property can be used to indicate the source of lead pollutants in the environment. The wolld production of primary lead is tabulated, and the geochemical significances of lead isotope ratios are discussed. The manufacture of lead alkyl additives for gasoline, which is the major source of lead pollutants, utilizes about 10% of the world annual consumption of lead. The isotope ratios of lead in gasoline, aerosols, soils and plants are correlated. Lead additives in various brands of gasoline sold in one region do not have the same isotope ratios. Regional variations in isotope ratios of lead additives were observed. This reflects the fact that petroleum refineries obtained the additives from various lead alkyl manufacturers which utilized lead from different mining districts. A definite changing trend of isotope ratios of lead pollutants in the San Diego, California (USA), area was detected. The lead shows a gradual increase in its radiogenic components during the past decade. This trend can be explained by the change of lead sources used by the additive manufacturers: Lead isotope ratios of the mid-1960's gasoline additives in the United States of America reflected those of less radiogenic leads imported from Canada, Australia, Peru and Mexico. Since then, the U.S. lead production has doubled-mainly from the Missouri district of highly radiogenic lead. Meanwhile, there has been a decrease in total lead imports. These combined effects result in changes in isotope ratios, from the less to more radiogenic, of the pooled lead. (aothor)

Maternal preconception diet and the sex ratio

NARCIS (Netherlands)

Cramer, J.S.; Lumey, L.H.

2010-01-01

Temporal variations in the sex ratio, or the ratio of boys to girls at birth, have been widely studied and variously attributed to social changes, conditions of war, and environmental changes. Recently, Mathews et al. ["You are what your mother eats: Evidence for maternal preconception diet

SOLVENCY RATIO AS A TOOL FOR BANKRUPTCY PREDICTION

Directory of Open Access Journals (Sweden)

Daniel BRÎNDESCU–OLARIU

2016-08-01

Full Text Available The current study evaluates the potential of the solvency ratio in predicting corporate bankruptcy. The research is focused on Romania and, in particular, on Timis County. The interest for the solvency ratio was based on the recommendations of the scientific literature, as well as on the availability of information concerning its values to all stakeholders. The event on which the research was focused was represented by the manifestation of bankruptcy 2 years after the date of the financial statements of reference. All tests were performed over 2 paired samples of 1176 companies in total. The methodology employed in evaluating the potential of the solvency ratio was based on the Area Under the ROC Curve (0.646 and the general accuracy ensured by the ratio (64.5% out-of-sample accuracy. The results confirm the practical utility of the solvency ratio in the prediction of bankruptcy.

Recent development in isotope ratio mass spectrometry

International Nuclear Information System (INIS)

Platzner, I.

1992-01-01

Within the limited of this review the following topics will be briefly discussed: a) Accuracy, precision, internal relative standard deviation (RISD) and external relative standard deviation (RESD) of isotope ratio measurements. With advanced instrumentation and use of standard reference materials, high accuracy and RESD = 0.002% (or better) may be achieved; b) The advantages of modern automatic isotope ratio mass spectrometer are briefly described. Computer controlled operation and data acquisition, and multiple ion collection are the recent important improvement; c) The isotopic fractionation during the course of isotope ratio measurement is considered as a major source of errors in thermal ionization of metallic elements. The phenomenon in strontium, neodymium, uranium, lead and calcium and methods to correct the measured data are discussed; d) Applications of isotope ratio mass spectrometry in atomic weight determinations, the isotope dilution technique, isotope geology, and isotope effects in biological systems are described together with specific applications in various research and technology area. (author)

Sex allocation and secondary sex ratio in Cuban boa ( Chilabothrus angulifer): mother's body size affects the ratio between sons and daughters

Science.gov (United States)

Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

2016-06-01

Secondary sex ratios of animals with genetically determined sex may considerably deviate from equality. These deviations may be attributed to several proximate and ultimate factors. Sex ratio theory explains some of them as strategic decisions of mothers improving their fitness by selective investment in sons or daughters, e.g. local resource competition hypothesis (LRC) suggests that philopatric females tend to produce litters with male-biased sex ratios to avoid future competition with their daughters. Until now, only little attention has been paid to examine predictions of sex ratio theory in snakes possessing genetic sex determination and exhibiting large variance in allocation of maternal investment. Cuban boa is an endemic viviparous snake producing large-bodied newborns (˜200 g). Extremely high maternal investment in each offspring increases importance of sex allocation. In a captive colony, we collected breeding records of 42 mothers, 62 litters and 306 newborns and examined secondary sex ratios (SR) and sexual size dimorphism (SSD) of newborns. None of the examined morphometric traits of neonates appeared sexually dimorphic. The sex ratio was slightly male biased (174 males versus 132 females) and litter sex ratio significantly decreased with female snout-vent length. We interpret this relationship as an additional support for LRC as competition between mothers and daughters increases with similarity of body sizes between competing snakes.

The Golden Ratio in Time-based Media

Directory of Open Access Journals (Sweden)

Emily Verba

2013-06-01

Full Text Available Measure and proportion manifest themselves in all areas of beauty and virtue.–Socrates Mathematics and visual communication share a long historical, symbiotic relationship. In their pursuit of achieving order and beauty, they find common ground through geometry. The golden ratio is a mathematic and aesthetic phenomenon inherent in nature that has consistently evoked sensory enjoyment since antiquity. It may be assumed that the manifestation of the golden ratio in nature accounts for human’s innate enjoyment of it. Throughout the ages, the conscious application of the golden ratio to proportions found in art, architecture, poetry, literature and musical composition has consistently evoked subconscious sensory pleasure. However, the application of the golden ratio to visual temporal proportion, or time-based media, has seldom been investigated. This thesis investigates various applications of the golden ratio as a mathematical framework for choreographing visually harmonious temporal compositions through time-based media. The proliferation of moving images we face on a daily basis is cause for great concern, as we have increasingly less free time in our days. Informative and pleasing images are buried in an avalanche of visual rubbish, constantly streaming into our physical and virtual worlds. Time-based media has the ability to expand and contract movement, thus directing the way viewers experience and spend their time. This investigation presupposes that editing moving images via increments of time determined by the golden ratio may streamline messages, isolating what is most symbolic and effectively communicative within a mathematical framework. A physiological and psychological benefit is created for viewers; there is no wasted time or space. Image-makers and visual communicators have a responsibility to create only that which is useful and/or aesthetically pleasing. An investigation into the temporal structure of time-based media, using

Effect of H/C ratio on coal ignition

Energy Technology Data Exchange (ETDEWEB)

Furimsky, E.

1988-09-01

The Cahn balance technique was found to be suitable for estimating ignition temperature and its dependence on the H/C ratio of the coal. This temperature decreased with increasing H/C ratio of coals. For coals a linear correlation between H/C ratio and the temperature was established. Chars derived from the coals deviated from the linear correlation established on coals. 17 refs., 4 figs.

Elevated sacroilac joint uptake ratios in systemic lupus erythematosus

International Nuclear Information System (INIS)

De Smet, A.A.; Mahmood, T.; Robinson, R.G.; Lindsley, H.B.

1984-01-01

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

12 CFR 3.6 - Minimum capital ratios.

Science.gov (United States)

2010-01-01

... should have well-diversified risks, including no undue interest rate risk exposure; excellent control... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Minimum capital ratios. 3.6 Section 3.6 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY MINIMUM CAPITAL RATIOS; ISSUANCE...

Rotator Cuff Strength Ratio and Injury in Glovebox Workers

Energy Technology Data Exchange (ETDEWEB)

Weaver, Amelia M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2014-01-30

Rotator cuff integrity is critical to shoulder health. Due to the high workload imposed upon the shoulder while working in an industrial glovebox, this study investigated the strength ratio of the rotator cuff muscles in glovebox workers and compared this ratio to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forces produced in the motions of shoulder internal and external rotation. Results showed this population to have shoulder strength ratios that were significantly different from the healthy norm. The deviation from the normal ratio demonstrates the need for solutions designed to reduce the workload on the rotator cuff musculature of glovebox workers in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development.

Corporate prediction models, ratios or regression analysis?

NARCIS (Netherlands)

Bijnen, E.J.; Wijn, M.F.C.M.

1994-01-01

The models developed in the literature with respect to the prediction of a company s failure are based on ratios. It has been shown before that these models should be rejected on theoretical grounds. Our study of industrial companies in the Netherlands shows that the ratios which are used in

Analysis of the moderating ratio in BWR fuels

International Nuclear Information System (INIS)

Gomez, A.; Xolocostli, V.; Alonso, G.

2001-01-01

In all different light water nuclear reactors is very important the fuel assembly design. It has to be designed to achieve safety and efficiency performance in an economical way. The moderating ratio plays a very important role because an adequate election can provide an optimal energy production making the fuel assembly more efficient. This work analyze the moderation ratio as a function of the fuel assembly enrichment and ifs burnup, based on this study the optimal moderation ratio are obtained. Furthermore, based on numerical relations some simulation schemes are proposed to describe the behavior of the infinite multiplication factor as a function of the moderating ratio for a given fuel assembly enrichment at zero burnup. (Author)

Study by the Prandtl-Glauert method of compressibility effects and critical Mach number for ellipsoids of various aspect ratios and thickness ratios

Science.gov (United States)

Hess, Robert V; Gardner, Clifford S

1947-01-01

By using the Prandtl-Glauert method that is valid for three-dimensional flow problems, the value of the maximum incremental velocity for compressible flow about thin ellipsoids at zero angle of attack is calculated as a function of the Mach number for various aspect ratios and thickness ratios. The critical Mach numbers of the various ellipsoids are also determined. The results indicate an increase in critical Mach number with decrease in aspect ratio which is large enough to explain experimental results on low-aspect-ratio wings at zero lift.

Ultima Ratio and the Judicial Application of Law

Directory of Open Access Journals (Sweden)

Joxerramon Bengoetxea

2013-01-01

Full Text Available The nature of Ultima Ratio as a principle, its relationship to other principles in the criminal law is the first subject of this paper. After discarding approaches that deny any role to the ultima ratio principle like the criminal law of the enemy, the major readings of the justification of the ius puniendi – deontological and utilitarian – are related to the idea of a restrained resort to criminalisation and penal sanction. The role of the main protagonists in relation to punishment is next considered: transgressor, community and victim. The issues of impunity and overpunity are also considered in this part. The second part of the paper analyses the possible effects of ultima ratio, a general politico-moral principle mainly addressed to the legislator, on the application of the law by the judges. It is then turned into something closer to a general legal principle. The impact of ultima ratio on the different sub-decisions of the judicial application of the criminal law is spelt out in the decisions on qualification, evidence (inferences, interpretation and consequences in sentencing. Next, the role of ultima ratio on decisions in appeal and in cassation is analysed. The third part and conclusion deals with the main ideologies of ultima ratio and the wider issue of its role in securing a guarantee oriented criminal law in Europe. En este artículo se aborda, en primer lugar, el carácter de ultima ratio como principio, su relación con otros principios en el derecho penal. Después de descartar los enfoques que rechazan cualquier papel del principio de ultima ratio como el derecho penal del enemigo, las lecturas principales de la justificación del ius puniendi, deontológico y utilitarista, están relacionadas con la idea de un recurso restringido a la criminalización y sanción penal. A continuación, se analiza el papel de los protagonistas principales relacionados con el castigo: transgresor, comunidad y víctima. En esta parte tambi

Ratio method of measuring W boson mass

Energy Technology Data Exchange (ETDEWEB)

Guo, Feng [Stony Brook Univ., NY (United States)

2010-08-01

This dissertation describes an alternative method of measuring the W boson mass in DØ experiment. Instead of extracting M_W from the fitting of W → ev fast Monte Carlo simulations to W → ev data as in the standard method, we make the direct fit of transverse mass between W → ev data and Z → ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (M_W/M_Z). Given the precisely measured Z boson mass, W mass is directly fitted from W → ev and Z → ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb^-1 DØ Run IIa dataset, ratio method gives M_W = 80435 ± 43(stat) ± 26(sys) MeV.

Isotope ratio in stellar atmospheres and nucleosynthesis

International Nuclear Information System (INIS)

Barbuy, B.L.S.

1987-01-01

The determination of isotopic ratios in stellar atmospheres is studied. The isotopic shift of atomic and molecular lines of different species of a certain element is examined. CH and MgH lines are observed in order to obtain the 12 C: 13 C and 24 Mg: 25 Mg: 26 Mg isotpic ratios. The formation of lines in stellar atmospheres is computed and the resulting synthetic spectra are employed to determine the isotopic abundances. The results obtained for the isotopic ratios are compared to predictions of nucleosynthesis theories. Finally, the concept of primary and secondary element is discussed, and these definitions are applied to the observed variations in the abundance of elements as a function of metallicity. (author) [pt

The rectilinear Steiner ratio

Directory of Open Access Journals (Sweden)

PO de Wet

2005-06-01

Full Text Available The rectilinear Steiner ratio was shown to be 3/2 by Hwang [Hwang FK, 1976, On Steiner minimal trees with rectilinear distance, SIAM Journal on Applied Mathematics, 30, pp. 104– 114.]. We use continuity and introduce restricted point sets to obtain an alternative, short and self-contained proof of this result.

PROFITABILITY RATIO AS A TOOL FOR BANKRUPTCY PREDICTION

Directory of Open Access Journals (Sweden)

Daniel BRÎNDESCU – OLARIU

2016-07-01

Full Text Available The current study evaluates the potential of the profitability ratio in predicting corporate bankruptcy. The research is focused on Romanian companies, with the targeted event being represented by the manifestation of bankruptcy 2 years after the date of the financial statements of reference. All tests were conducted over 2 paired samples of 1176 Romanian companies. The methodology employed in evaluating the potential of the profitability ratio was based on the Area Under the ROC Curve (0.663 and the general accuracy ensured by the ratio (62.6% out-of-sample accuracy. The results confirm the practical utility of the profitability ratio in the prediction of bankruptcy and thus validate the need for further research focused on developing a methodology of analysis.

Tau hadronic branching ratios

CERN Document Server

Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

1996-01-01

From 64492 selected \\tau-pair events, produced at the Z^0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and \\pi^0's, and the removal of fake photons. A detailed study of the systematics entering the \\pi^0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test of \\tau-\\mu universality in hadronic decays, g_\\tau/g_\\mu \\ = \\ 1.0013 \\ \\pm \\ 0.0095, and the first measurement of the vector and axial-vector contributions to the non-strange hadronic \\tau decay width: R_{\\tau ,V} \\ = \\ 1.788 \\ \\pm \\ 0.025 and R_{\\tau ,A} \\ = \\ 1.694 \\ \\pm \\ 0.027. The ratio (R_{\\tau ,V} - R_{\\tau ,A}) / (R_{\\tau ,V} + R_{\\tau ,A}), equal to (2.7 \\pm 1.3) \\ \\%, is a measure of the importance of Q...

National, regional, and global sex ratios of infant, child, and under-5 mortality and identification of countries with outlying ratios: a systematic assessment.

Science.gov (United States)

Alkema, Leontine; Chao, Fengqing; You, Danzhen; Pedersen, Jon; Sawyer, Cheryl C

2014-09-01

Under natural circumstances, the sex ratio of male to female mortality up to the age of 5 years is greater than one but sex discrimination can change sex ratios. The estimation of mortality by sex and identification of countries with outlying levels is challenging because of issues with data availability and quality, and because sex ratios might vary naturally based on differences in mortality levels and associated cause of death distributions. For this systematic analysis, we estimated country-specific mortality sex ratios for infants, children aged 1-4 years, and children under the age of 5 years (under 5s) for all countries from 1990 (or the earliest year of data collection) to 2012 using a Bayesian hierarchical time series model, accounting for various data quality issues and assessing the uncertainty in sex ratios. We simultaneously estimated the global relation between sex ratios and mortality levels and constructed estimates of expected and excess female mortality rates to identify countries with outlying sex ratios. Global sex ratios in 2012 were 1·13 (90% uncertainty interval 1·12-1·15) for infants, 0·95 (0·93-0·97) for children aged 1-5 years, and 1·08 (1·07-1·09) for under 5s, an increase since 1990 of 0·01 (-0·01 to 0·02) for infants, 0·04 (0·02 to 0·06) for children aged 1-4 years, and 0·02 (0·01 to 0·04) for under 5s. Levels and trends varied across regions and countries. Sex ratios were lowest in southern Asia for 1990 and 2012 for all age groups. Highest sex ratios were seen in developed regions and the Caucasus and central Asia region. Decreasing mortality was associated with increasing sex ratios, except at very low infant mortality, where sex ratios decreased with total mortality. For 2012, we identified 15 countries with outlying under-5 sex ratios, of which ten countries had female mortality higher than expected (Afghanistan, Bahrain, Bangladesh, China, Egypt, India, Iran, Jordan, Nepal, and Pakistan). Although excess female

The Ratio Between Metastatic and Examined Lymph Nodes (N Ratio) Is an Independent Prognostic Factor in Gastric Cancer Regardless of the Type of Lymphadenectomy

Science.gov (United States)

Marchet, Alberto; Mocellin, Simone; Ambrosi, Alessandro; Morgagni, Paolo; Garcea, Domenico; Marrelli, Daniele; Roviello, Franco; de Manzoni, Giovanni; Minicozzi, Annamaria; Natalini, Giovanni; De Santis, Francesco; Baiocchi, Luca; Coniglio, Arianna; Nitti, Donato

2007-01-01

Purpose: To investigate whether the ratio between metastatic and examined lymph nodes (N ratio) is a better prognostic factor as compared with traditional staging systems in patients with gastric cancer regardless of the extension of lymph node dissection. Patients & Methods: We retrospectively reviewed the data of 1853 patients who underwent radical resection for gastric carcinoma at 6 Italian centers. Patients with >15 (group 1, n = 1421) and those with ≤15 (group 2, n = 432) lymph nodes examined were separately analyzed. N ratio categories (N ratio 0, 0%; N ratio 1, 1%–9%; N ratio 2, 10%–25%; N ratio 3, >25%) were determined by the best cut-off approach. Results: After a median follow-up of 45.5 months (range, 4–182 months), the 5-year overall survival of N0, N1, and N2 patients of group 1 versus group 2 was 83.4% versus 74.2% (P = 0.0026), 54.3% versus 44.3% (P = 0.018), and 32.7% versus 14.7% (P = 0.004), respectively, suggesting that a low number of excised lymph nodes can lead to the understaging of patients. N ratio identified subsets of patients with significantly different survival rates within N1 and N2 stages in both groups. At multivariate analysis, the N ratio (but not N stage) was retained as an independent prognostic factor both in group 1 and group 2 (HR for N ratio 1, N ratio 2, and N ratio 3 = 1.67, 2.96, and 6.59, and 1.56, 2.68, and 4.28, respectively). In our series, the implementation of N ratio led to the identification of subgroups of patients prognostically more homogeneous than those classified by the TNM system. Conclusion: N ratio is a simple and reproducible prognostic tool that can stratify patients with gastric cancer also in case of limited lymph node dissection. These data may represent the rational for improving the prognostic power of current UICC TNM staging system and ultimately the selection of patients who may most benefit from adjuvant treatments. PMID:17414602

Correlation Between Cometary Gas/Dust Ratios and Heliocentric Distance

Science.gov (United States)

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.

Skewed sex ratios and criminal victimization in India.

Science.gov (United States)

South, Scott J; Trent, Katherine; Bose, Sunita

2014-06-01

Although substantial research has explored the causes of India's excessively masculine population sex ratio, few studies have examined the consequences of this surplus of males. We merge individual-level data from the 2004-2005 India Human Development Survey with data from the 2001 India population census to examine the association between the district-level male-to-female sex ratio at ages 15 to 39 and self-reports of victimization by theft, breaking and entering, and assault. Multilevel logistic regression analyses reveal positive and statistically significant albeit substantively modest effects of the district-level sex ratio on all three victimization risks. We also find that higher male-to-female sex ratios are associated with the perception that young unmarried women in the local community are frequently harassed. Household-level indicators of family structure, socioeconomic status, and caste, as well as areal indicators of women's empowerment and collective efficacy, also emerge as significant predictors of self-reported criminal victimization and the perceived harassment of young women. The implications of these findings for India's growing sex ratio imbalance are discussed.

Skewed Sex Ratios and Criminal Victimization in India

Science.gov (United States)

South, Scott J.; Trent, Katherine; Bose, Sunita

2014-01-01

Although substantial research has explored the causes of India’s excessively masculine population sex ratio, few studies have examined the consequences of this surplus of males. We merge individual-level data from the 2004–2005 India Human Development Survey with data from the 2001 India population census to examine the association between the district-level male-to-female sex ratio at ages 15 to 39 and self-reports of victimization by theft, breaking and entering, and assault. Multilevel logistic regression analyses reveal positive and statistically significant albeit substantively modest effects of the district-level sex ratio on all three victimization risks. We also find that higher male-to-female sex ratios are associated with the perception that young unmarried women in the local community are frequently harassed. Household-level indicators of family structure, socioeconomic status, and caste, as well as areal indicators of women’s empowerment and collective efficacy, also emerge as significant predictors of self-reported criminal victimization and the perceived harassment of young women. The implications of these findings for India’s growing sex ratio imbalance are discussed. PMID:24682921

Skewed sex ratios in India: "physician, heal thyself".

Science.gov (United States)

Patel, Archana B; Badhoniya, Neetu; Mamtani, Manju; Kulkarni, Hemant

2013-06-01

Sex selection, a gender discrimination of the worst kind, is highly prevalent across all strata of Indian society. Physicians have a crucial role in this practice and implementation of the Indian Government's Pre-Natal Diagnostic Techniques Act in 1996 to prevent the misuse of ultrasound techniques for the purpose of prenatal sex determination. Little is known about family preferences, let alone preferences among families of physicians. We investigated the sex ratios in 946 nuclear families with 1,624 children, for which either one or both parents were physicians. The overall child sex ratio was more skewed than the national average of 914. The conditional sex ratios decreased with increasing number of previous female births, and a previous birth of a daughter in the family was associated with a 38 % reduced likelihood of a subsequent female birth. The heavily skewed sex ratios in the families of physicians are indicative of a deeply rooted social malady that could pose a critical challenge in correcting the sex ratios in India.

Stable isotope ratio determination of the origin of vanillin in vanilla extracts and its relationship to vanillin/potassium ratios

International Nuclear Information System (INIS)

Martin, G.E.; Alfonso, F.C.; Figert, D.M.; Burggraff, J.M.

1981-01-01

A method is described for isolating vanillin from vanilla extract, followed by stable isotope ratio analysis to determine the amount of natural vanillin contained in adulterated vanilla extracts. After the potassium content is determined, the percent Madagascar and/or Java vanilla beans incorporated into the extract may then be approximated from the vanillin/potassium ratio

Sex ratios of Mountain Plovers from egg production to fledging

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Margaret M. Riordan

2015-12-01

Full Text Available Skewed sex ratios can have negative implications for population growth if they do not match a species' life history. A skewed tertiary sex ratio has been detected in a population of Mountain Plover (Charadrius montanus, a grassland shorebird experiencing population declines. To study the cause of the observed male skew, we examined three early life stages between egg and fledgling in eastern Colorado from 2010 to 2012. This allows us to distinguish between egg production and chick survival as an explanation for the observed skew. We examined the primary sex ratio in eggs produced and the secondary sex ratio in hatched chicks to see if the sex ratio bias occurs before hatching. We also determined the sex ratio at fledging to reveal sex-specific mortality of nestlings. The primary sex ratio was 1.01 (± 0.01 males per female. The secondary sex ratio consisted of 1.10 (± 0.02 males per female. The probability of a chick surviving to fledging differed between males (0.55 ± 0.13 and females (0.47 ± 0.15, but the precision of these survival estimates was low. Sex ratios in early life stages of the Mountain Plover do not explain the skewed sex ratio observed in adults in this breeding population.

PAH diagnostic ratios for the identification of pollution emission sources

International Nuclear Information System (INIS)

Tobiszewski, Marek; Namieśnik, Jacek

2012-01-01

Polycyclic aromatic hydrocarbon (PAH) diagnostic ratios have recently come into common use as a tool for identifying and assessing pollution emission sources. Some diagnostic ratios are based on parent PAHs, others on the proportions of alkyl-substituted to non-substituted molecules. The ratios are applicable to PAHs determined in different environmental media: air (gas + particle phase), water, sediment, soil, as well as biomonitor organisms such as leaves or coniferous needles, and mussels. These ratios distinguish PAH pollution originating from petroleum products, petroleum combustion and biomass or coal burning. The compounds involved in each ratio have the same molar mass, so it is assumed they have similar physicochemical properties. Numerous studies show that diagnostic ratios change in value to different extents during phase transfers and environmental degradation. The paper reviews applications of diagnostic ratios, comments on their use and specifies their limitations. - Highlights: ► PAH diagnostic ratios may identify pollution coming from petroleum spills, fuel combustion and coal or biomass burning. ► They are sensitive to changes during PAHs environmental fate processes. ► Some diagnostic ratios are of limited value due to fast photodegradation of one of the compounds. - The paper reviews PAH diagnostic ratios that are applied to identify pollution emission originating from petroleum products, fuel combustion or coal and biomass burning.

41 CFR 109-27.5002 - Stores inventory turnover ratio.

Science.gov (United States)

2010-07-01

... turnover ratio. 109-27.5002 Section 109-27.5002 Public Contracts and Property Management Federal Property....5002 Stores inventory turnover ratio. Comparison of investment in stores inventories to annual issues... comparison may be expressed either as a turnover ratio (dollar value of issues divided by dollar value of...

Neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in mood disorders: A meta-analysis.

Science.gov (United States)

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 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 are needed. Copyright © 2018 Elsevier Inc. All rights reserved.

Survey of literature on dispersion ratio and collection ratio of radioisotopes in animal study using radioisotopes

International Nuclear Information System (INIS)

Tozuka, Zenzaburo; Doi, Masahiro; Miyazawa, Eiji; Kawakami, Takeo

1998-01-01

A survey of literature in the title was performed to know the actual status of the dispersion from excretion and expiration studies of radioisotopes since, at present, the probable dispersion ratio is assumed to be 100% in calculation for legally permitted use of radioisotopes which conceivably being far from the real status and being incompatible with the guideline for pharmacokinetic studies requiring the recovery of >95% of dosed radioactivity in balance study. There are two interpretations for the dispersion; it is the expiration ratio and it is the fraction unrecovered. Survey was done on 11 Japanese and foreign journals in 1985-1996 publishing most of pharmacokinetic studies and on 650 compounds in 358 facilities with 1,975 experiments in total. In those experiments, the total recovery of radioactivity was 95% in average, unrecovered fraction, 5% and expiration ratio, 2%. As for unclide, 14 C, 3 H, 125 I and 35 S were surveyed since they occupied 99.4% of the experiments and their dispersion was <5%. Rats were used in 70% of the experiments and the dispersion in all animal experiments was about 5%. Administration route was regardless of the dispersion. (K.H.)

Ratio Bias and Policy Preferences

DEFF Research Database (Denmark)

Pedersen, Rasmus Tue

2017-01-01

Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...... is a general tendency to focus on numerators and pay insufficient attention to denominators in ratios. Using a population-based survey experiment, I demonstrate how differently framed but logically equivalent representations of the exact same numerical value can have large effects on citizens’ preferences...... regarding salient political issues such as education and taxes. Furthermore, the effects of numerical framing are found across most groups of the population, largely regardless of their political predisposition and their general ability to understand and use numerical information. These findings have...

CASH AND LIQUIDITY/LIQUIDITY AND LIQUIDITY RATIO

Directory of Open Access Journals (Sweden)

BEATRIX LIGHEZAN BREUER

2012-12-01

Full Text Available The present paper aims to present the correlation as well as the differences between liquidity/cash and liquidity ratio in terms of economic entities. Researches on this topic are based on the opinions of some specialists in accounting and in the economic-financial analysis, as well as on the national legal stipulations and the ones set out in the International Accounting Standards, the Financial report, respectively. The object of this paper is represented by the correlation between liquidity/cash and liquidity ratios representing the liquidity as current assets, assets implied in the determination of liquidity ratios. The end of the paper consists of the conclusions drawn from the issues presented in the paper but also our views on this research topic.

Amplitude ratios in ρ0 leptoproductions and GPDs

Directory of Open Access Journals (Sweden)

Goloskokov S.V.

2017-01-01

Using the model results we calculate the ratio of different helicity amplitudes for a transversely polarized proton target to the leading twist longitudinal amplitude. Our results are close to the amplitude ratios measured by HERMES.

Potential support ratios

DEFF Research Database (Denmark)

Kjærgaard, Søren; Canudas-Romo, Vladimir

2017-01-01

The ‘prospective potential support ratio’ has been proposed by researchers as a measure that accurately quantifies the burden of ageing, by identifying the fraction of a population that has passed a certain measure of longevity, for example, 17 years of life expectancy. Nevertheless......, the prospective potential support ratio usually focuses on the current mortality schedule, or period life expectancy. Instead, in this paper we look at the actual mortality experienced by cohorts in a population, using cohort life tables. We analyse differences between the two perspectives using mortality models...

The relationship between size, book-to-market equity ratio, earnings–price ratio, and return for the Tehran stock Exchange

Directory of Open Access Journals (Sweden)

Mohammad Ali Sadeghi Lafmejani

2016-01-01

Full Text Available This paper presents an empirical investigation to determine whether or there is any difference between the returns of two value and growth portfolios, sorted by price-to-earnings (P/E and price-to-book value (P/BV, in terms of the ratios of market sensitivity to index (β, firm size and market liquidity in listed firms in Tehran Stock Exchange (TSE over the period 2001-2008. The selected firms were collected from those with existing two-consecutive positive P/E and P/BV ratios and by excluding financial and holding firms. There were five independent variables for the proposed study of this paper including P/E, P/B, market size, market sensitivity beta (β and market liquidity. In each year, we first sort firms in non-decreasing order and setup four set of portfolios with equal firms. Therefore, the first portfolio with the lowest P/E ratio is called value portfolio and the last one with the highest P/E ratio is called growth portfolio. This process was repeated based on P/BV ratio to determine value and growth portfolios, accordingly. The study investigated the characteristics of two portfolios based on firm size, β and liquidity. The study has implemented t-student and Levin’s test to examine different hypotheses and the results have indicated mix effects of market sensitivity, firm size and market liquidity on returns of the firms in various periods.

Experimental characterization of the concrete behaviour under high confinement: influence of the saturation ratio and of the water/cement ratio

International Nuclear Information System (INIS)

Vu, X.H.

2007-08-01

The objective of this thesis is to experimentally characterize the influence of the saturation ratio and of the water/cement ratio of concrete on its behaviour under high confinement. This thesis lies within a more general scope of the understanding of concrete behaviour under severe loading situations (near field detonation or ballistic impacts). A near field detonation or an impact on a concrete structure generate very high levels of stress associated with complex loading paths in the concrete material. To validate concrete behaviour models, experimental results are required. The work presented in this thesis concerns tests conducted using a static triaxial press that allows to obtain stress levels of the order of the giga Pascal. The porous character of concrete and the high confinement required on the one hand, a development of a specimen protection device, and on the other hand, a development of an instrumentation with strain gauges, which is unprecedented for such high confinements. Hydrostatic and triaxial tests, conducted on the one hand on model materials and on the other hand on concrete, allowed to validate the developed experimental procedures as well as the technique of strain and stress measurements. The studies concerning the influence of the saturation ratio and of the water/cement ratio of concrete on its behaviour required the formulation of a plain baseline concrete and of two modified concretes with different water/cement ratios. The analysis of triaxial tests performed on the baseline concrete shows that the saturation ratio of concrete has a major influence on its static behaviour under high confinement. This influence is particularly marked for the concrete loading capacity and for the shape of limit state curves for saturation ratios greater than 50%. The concrete loading capacity increases with the confinement pressure for tests on dry concrete whereas beyond a given confinement pressure, it remains limited for wet or saturated concrete

Statistical moments of the Strehl ratio

Science.gov (United States)

Yaitskova, Natalia; Esselborn, Michael; Gladysz, Szymon

2012-07-01

Knowledge of the statistical characteristics of the Strehl ratio is essential for the performance assessment of the existing and future adaptive optics systems. For full assessment not only the mean value of the Strehl ratio but also higher statistical moments are important. Variance is related to the stability of an image and skewness reflects the chance to have in a set of short exposure images more or less images with the quality exceeding the mean. Skewness is a central parameter in the domain of lucky imaging. We present a rigorous theory for the calculation of the mean value, the variance and the skewness of the Strehl ratio. In our approach we represent the residual wavefront as being formed by independent cells. The level of the adaptive optics correction defines the number of the cells and the variance of the cells, which are the two main parameters of our theory. The deliverables are the values of the three moments as the functions of the correction level. We make no further assumptions except for the statistical independence of the cells.

Measurement of the temperature coefficient of ratio transformers

Science.gov (United States)

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.

The Improved Estimation of Ratio of Two Population Proportions

Science.gov (United States)

Solanki, Ramkrishna S.; Singh, Housila P.

2016-01-01

In this article, first we obtained the correct mean square error expression of Gupta and Shabbir's linear weighted estimator of the ratio of two population proportions. Later we suggested the general class of ratio estimators of two population proportions. The usual ratio estimator, Wynn-type estimator, Singh, Singh, and Kaur difference-type…

Hepatic MR imaging for in vivo differentiation of steatosis, iron deposition and combined storage disorder: Single-ratio in/opposed phase analysis vs. dual-ratio Dixon discrimination

International Nuclear Information System (INIS)

Bashir, Mustafa R.; Merkle, Elmar M.; Smith, Alastair D.; Boll, Daniel T.

2012-01-01

Objective: To assess whether in vivo dual-ratio Dixon discrimination can improve detection of diffuse liver disease, specifically steatosis, iron deposition and combined disease over traditional single-ratio in/opposed phase analysis. Methods: Seventy-one patients with biopsy-proven (17.7 ± 17.0 days) hepatic steatosis (n = 16), iron deposition (n = 11), combined deposition (n = 3) and neither disease (n = 41) underwent MR examinations. Dual-echo in/opposed-phase MR with Dixon water/fat reconstructions were acquired. Analysis consisted of: (a) single-ratio hepatic region-of-interest (ROI)-based assessment of in/opposed ratios; (b) dual-ratio hepatic ROI assessment of in/opposed and fat/water ratios; (c) computer-aided dual-ratio assessment evaluating all hepatic voxels. Disease-specific thresholds were determined; statistical analyses assessed disease-dependent voxel ratios, based on single-ratio (a) and dual-ratio (b and c) techniques. Results: Single-ratio discrimination succeeded in identifying iron deposition (I/O Ironthreshold Fatthreshold>1.15 ) from normal parenchyma, sensitivity 70.0%; it failed to detect combined disease. Dual-ratio discrimination succeeded in identifying abnormal hepatic parenchyma (F/W Normalthreshold > 0.05), sensitivity 96.7%; logarithmic functions for iron deposition (I/O Iron d iscriminator (0.01−F/W Iron )/0.48 ) and for steatosis (I/O Fatdiscriminator > e (F/W Fat −0.01)/0.48 ) differentiated combined from isolated diseases, sensitivity 100.0%; computer-aided dual-ratio analysis was comparably sensitive but less specific, 90.2% vs. 97.6%. Conclusion: MR two-point-Dixon imaging using dual-ratio post-processing based on in/opposed and fat/water ratios improved in vivo detection of hepatic steatosis, iron deposition, and combined storage disease beyond traditional in/opposed analysis.

A note on Youden's J and its cost ratio

Directory of Open Access Journals (Sweden)

Smits Niels

2010-09-01

Full Text Available Abstract Background The Youden index, the sum of sensitivity and specificity minus one, is an index used for setting optimal thresholds on medical tests. Discussion When using this index, one implicitly uses decision theory with a ratio of misclassification costs which is equal to one minus the prevalence proportion of the disease. It is doubtful whether this cost ratio truly represents the decision maker's preferences. Moreover, in populations with a different prevalence, a selected threshold is optimal with reference to a different cost ratio. Summary The Youden index is not a truly optimal decision rule for setting thresholds because its cost ratio varies with prevalence. Researchers should look into their cost ratio and employ it in a decision theoretic framework to obtain genuinely optimal thresholds.

The Old-Age Healthy Dependency Ratio in Europe.

Science.gov (United States)

Muszyńska, Magdalena M; Rau, Roland

2012-09-01

The aim of this study is to answer the question of whether improvements in the health of the elderly in European countries could compensate for population ageing on the supply side of the labour market. We propose a state-of-health-specific (additive) decomposition of the old-age dependency ratio into an old-age healthy dependency ratio and an old-age unhealthy dependency ratio in order to participate in a discussion of the significance of changes in population health to compensate for the ageing of the labour force. Applying the proposed indicators to the Eurostat's population projection for the years 2010-2050, and assuming there will be equal improvements in life expectancy and healthy life expectancy at birth, we discuss various scenarios concerning future of the European labour force. While improvements in population health are anticipated during the years 2010-2050, the growth in the number of elderly people in Europe may be expected to lead to a rise in both healthy and unhealthy dependency ratios. The healthy dependency ratio is, however, projected to make up the greater part of the old-age dependency ratio. In the European countries in 2006, the value of the old-age dependency ratio was 25. But in the year 2050, with a positive migration balance over the years 2010-2050, there would be 18 elderly people in poor health plus 34 in good health per 100 people in the current working age range of 15-64. In the scenarios developed in this study, we demonstrate that improvements in health and progress in preventing disability will not, by themselves, compensate for the ageing of the workforce. However, coupled with a positive migration balance, at the level and with the age structure assumed in the Eurostat's population projections, these developments could ease the effect of population ageing on the supply side of the European labour market.

Assessment of the golden ratio in pleasing smiles.

Science.gov (United States)

Nikgoo, Arash; Alavi, Kamiar; Alavi, Kavah; Mirfazaelian, Ali

2009-01-01

The golden ratio is a guideline to help harmoniously restore or replace missing teeth. However, this concept is controversial. This study assesses the validity of the golden ratio between the widths of the maxillary anterior teeth in individuals presenting with an attractive/nonattractive smile. A double-stage random cluster sample cross-sectional study included 903 students whose ages ranged from 18 to 30 years and met the inclusion criteria. Image-measurement software was used to assess the perceived mesiodistal widths of the maxillary anterior teeth on scanned photographs. A jury of two dental professionals, a portrait photographer, and a painter, along with the respective subject as the fifth judge, determined the attractiveness of each smile on a visual analog scale. The mean value determined whether an individual was allocated to the attractive or nonattractive smile group. Finally, the prevalence of the golden ratio was investigated in these two groups. Intraobserver correlation coefficient was 0.966. Cochran's chi-square test was used for data analysis. According to the jury, 143 individuals had an attractive smile and 289 had a nonattractive smile. Maxillary central to lateral incisor ratio showed the golden proportion in 50.3% of the students with an attractive smile as compared to 38.1% in the nonattractive smile group (P =.014). However, the golden ratio between the maxillary lateral incisors and the canines existed in only 16.8% of the individuals with an attractive smile as compared to 12.1% in the nonattractive smile group (P =.223). The golden ratio can be useful to achieve esthetic restorations of the maxillary central and lateral incisors. However, the golden ratio between the perceived widths of the maxillary lateral incisors to the canines does not seem to be decisive for an attractive smile and other factors should be considered. © 2009 BY QUINTESSENCE PUBLISHING CO, INC.

The HNC/HCN ratio in star-forming regions

International Nuclear Information System (INIS)

Graninger, Dawn M.; Öberg, Karin I.; Herbst, Eric; Vasyunin, Anton I.

2014-01-01

HNC and HCN, typically used as dense gas tracers in molecular clouds, are a pair of isomers that have great potential as a temperature probe because of temperature dependent, isomer-specific formation and destruction pathways. Previous observations of the HNC/HCN abundance ratio show that the ratio decreases with increasing temperature, something that standard astrochemical models cannot reproduce. We have undertaken a detailed parameter study on which environmental characteristics and chemical reactions affect the HNC/HCN ratio and can thus contribute to the observed dependence. Using existing gas and gas-grain models updated with new reactions and reaction barriers, we find that in static models the H + HNC gas-phase reaction regulates the HNC/HCN ratio under all conditions, except for very early times. We quantitatively constrain the combinations of H abundance and H + HNC reaction barrier that can explain the observed HNC/HCN temperature dependence and discuss the implications in light of new quantum chemical calculations. In warm-up models, gas-grain chemistry contributes significantly to the predicted HNC/HCN ratio and understanding the dynamics of star formation is therefore key to model the HNC/HCN system.

The twenty-four/four hour ratio (T/F ratio) of Tc-99m MDP uptake in patients with bone metastases and degenerative changes

International Nuclear Information System (INIS)

Israel, O.; Kleinhaus, U.; Keren, R.; Frankel, A.; Front, D.

1984-01-01

Normal and metastatic bone differ in their histological structure. Normal bone is mainly lamellar while metastatic bone formation is made in a large part out of new woven bone. The woven bone has a much larger surface area than the more stable lamellar bone and it is lined with metabolically active osteoblasts. The crystalline structures in the woven bone are smaller and have a larger surface area available for absorption. Uptake of bone seeking radiopharmaceuticals continues in new woven bone longer than in the lamellar bone. Bone scintigraphy was performed in 89 patients at four hours and 24 hours using a digital camera. The lesion to non lesion (L/N) ratio was determined using the camera computer. The T/F ratio was calculated: T/F=((L/N)-24)/((L/N)-4). Three groups were investigated. In 15 patients with metastatic bone carcinoma, T/F ratio was 1.46 +- 0.4. In 47 patients with degenerative joint disease the T/F ratio was 1.05 +- 0.06. In 27 patients with treated metastatic bone carcinoma the T/F ratio was 1.12 +- 0.13. The T/F ratio is significantly (p<0.001) different in patients with metastases compared to patients with benign degenerative disease. Chemotherapeutic and hormonal treatment cause significant (p<0.001) reduction in the T/F ratio. The T/F ratio may have a potential in differentiating degenerative from neoplastic diseases and in the evaluation of patients with bone metastases undergoing treatment

Charge ratio of muons from atmospheric neutrinos

Energy Technology Data Exchange (ETDEWEB)

Gaisser, T.K.; Stanev, Todor

2003-05-22

We calculate the intensities and angular distributions of positive and negative muons produced by atmospheric neutrinos. We comment on some sources of uncertainty in the charge ratio. We also draw attention to a potentially interesting signature of neutrino oscillations in the muon charge ratio, and we discuss the prospects for its observation (which are not quite within the reach of currently planned magnetized detectors)

Increasing the transformer ratio at the Argonne wakefield accelerator

International Nuclear Information System (INIS)

Power, J.G.; Conde, M.; Liu, W.; Yusof, Z.; Gai, W.; Jing, C.; Kanareykin, A.

2011-01-01

The transformer ratio is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss experienced by the drive bunch (or a bunch within a multidrive bunch train). This plays an important role in the collinear wakefield acceleration scheme. A high transformer ratio is desirable since it leads to a higher overall efficiency under similar conditions (e.g. the same beam loading, the same structure, etc.). One technique to enhance the transformer ratio beyond the ordinary limit of 2 is to use a ramped bunch train. The first experimental demonstration observed a transformer ratio only marginally above 2 due to the mismatch between the drive microbunch length and the frequency of the accelerating structure (C. Jing, A. Kanareykin, J. Power, M. Conde, Z. Yusof, P. Schoessow, and W. Gai, Phys. Rev. Lett. 98, 144801 (2007)). Recently, we revisited this experiment with an optimized microbunch length using a UV laser stacking technique at the Argonne Wakefield Accelerator facility and measured a transformer ratio of 3.4. Measurements and data analysis from these experiments are presented in detail.

The reliability of four widely used patellar height ratios.

Science.gov (United States)

van Duijvenbode, Dennis; Stavenuiter, Michel; Burger, Bart; van Dijke, Cees; Spermon, Jacco; Hoozemans, Marco

2016-03-01

The objective of this study was to evaluate the inter-observer reliability and the intra-observer reliability of four patellar height ratios: Insall-Salvati (IS), modified Insall-Salvati (MIS), Blackburne-Peel (BP) and Caton-Deschamps (CD). The patellar height ratios were assessed by four independent examiners using weight-bearing lateral knee radiographs in 30° flexion. Intra-class correlation coefficients and Fleiss' kappa's were determined. The inter-observer reliability was excellent for the IS and moderate for the other ratios. When the ratio values were categorized, the inter-observer reliability was strong for the IS, moderate for the MIS and BP, and poor for the CD. The intra-observer reliability was excellent for the IS, MIS and CD, and strong for the BP. When the ratio values were categorized, the intra-observer reliability was strong for the IS and MIS, and moderate for the other ratios. Although the IS showed best reliability, we advise to use the MIS as it showed the second best reliability but is, according to the literature, associated with better validity.

Characterizing gamma fields using isomeric activation ratios

Science.gov (United States)

Venkataraman, Ramkumar; Fleming, Ronald F.

1994-12-01

Isomeric activities were induced in indium by gamma irradiation in three different gamma fields, through the reactions 115In(γ, γ') 115mIn and 113In(γ, γ') 113mIn. The irradiation fields were (i) the 15 kCi 60Co source available in the University, (ii) the spent fuel gamma irradiator in the pool of the University's Ford Nuclear Reactor (FNR) and (iii) south face of the core of the FNR during routine shut downs. Isomeric activation ratios can serve to characterize gamma fields, provided the response functions of the two (γ, γ') reactions sample different energy regimes of the gamma spectrum present in the irradiation fields. The response of an isomeric activation detector, in turn, depends on the number of activation energy levels of the nuclide and the probabilities with which the activation levels de-populate to the isomeric level. The reaction rate ratio RIn115m/ RIn113m was measured in the three gamma fields. The measured ratios were (i) 1.210 ± 0.011 in the 60Co source, (ii) 1.314 ± 0.060 in the spent fuel gamma irradiator and (iii) 1.298 ± 0.039 in a location alongside the FNR core during routine shut downs. The measured reaction rate ratios are not only close to each other, but close to unity as well. This indicates that the excitation functions for the reactions 115In(γ, γ') 115mIn and 113In(γ, γ') 113mIn have similar shapes and that for the nuclides 115In and 113In, the number of activation energy levels and the probabilities with which they populate the isomeric levels are very similar to each other. Thus, the ratio RIn115m/ RIn113m will not yield any information regarding the shape of gamma spectrum in the field of measurement. However by choosing (γ, γ') reactions with different shapes for the excitation functions one can measure a set of isomeric activation ratios that characterize a given gamma field.

Improved interpretation of renal-vein-renin-ratio by simultaneous determination of renal 131I-hippuric-acid-clearance-ratio in patients with renovascular hypertension

International Nuclear Information System (INIS)

Helber, A.; Boenner, G.; Hummerich, W.; Wambach, G.; Meurer, K.A.; Dvorak, K.; Lent, V.; Zehle, A.; Kaufmann, W.; Koeln Univ.; Staedtisches Krankenhaus Koeln-Merheim; Staedtisches Krankenhaus Koeln-Merheim; Koeln Univ.

1979-01-01

In patients with unilateral vascular kidney disease and hypertension, ratio of renal-vein-renin was compared with 131 I-Hippuric-acid clearance and change in blood pressure during Saralasininfusion. The ratio of renal-vein-renin was positively correlated with the ratio in renal plasma flow between the kidneys in all patients studied. The ratio of renins therefore is a result of two factors: The difference in renin secretion and the difference in blood flow in the two kidneys. In patients with angiotensin independent hypertension renin-ratios up to 2.0 were found without relevance to elevated blood pressure. When the difference in renal blood flow between both kidneys was small, even a slight difference in renal vein renin indicated hypertension related to increased renin secretion. (orig./AJ) [de

Do Workplace Sex Ratios Affect Partnership Formation and Dissolution?

DEFF Research Database (Denmark)

Svarer, Michael

In this paper, I analyse the association between workplace sex ratios and partnership formation and dissolution. I find that the risk of dissolution increases with the fraction of coworkers of the opposite sex at both the female and male workplace. On the other hand, workplace sex ratios are not ......In this paper, I analyse the association between workplace sex ratios and partnership formation and dissolution. I find that the risk of dissolution increases with the fraction of coworkers of the opposite sex at both the female and male workplace. On the other hand, workplace sex ratios...

Psychological distress during early gestation and offspring sex ratio

DEFF Research Database (Denmark)

Obel, C; Henriksen, TB; Secher, Niels Jørgen

2007-01-01

BACKGROUND: Exposure to severe stress in early pregnancy is associated with a lower male to female ratio (sex ratio), but whether more moderate levels of psychological discomfort have the same kind of effect is unknown. In a population based follow-up study, we aimed to test whether psychological...... suggest that not only severe stress, but also more moderate and common levels of psychological distress, may decrease the sex ratio in the offspring. Stress during pregnancy is a likely candidate involved in the decreasing sex ratio observed in many countries....... distress was associated with the sex ratio in the offspring. METHODS: From 1989 to 1992, a cohort of 8,719 Danish-speaking pregnant women were followed until delivery. Questionnaires were administered to the women in early pregnancy and 6,629 (76%) completed the 30-item version of the General Health...

Psychological distress during early gestation and offspring sex ratio

DEFF Research Database (Denmark)

Obel, Carsten; Henriksen, Tine Brink; Secher, Niels Jørgen

2007-01-01

BACKGROUND: Exposure to severe stress in early pregnancy is associated with a lower male to female ratio (sex ratio), but whether more moderate levels of psychological discomfort have the same kind of effect is unknown. In a population based follow-up study, we aimed to test whether psychological...... suggest that not only severe stress, but also more moderate and common levels of psychological distress, may decrease the sex ratio in the offspring. Stress during pregnancy is a likely candidate involved in the decreasing sex ratio observed in many countries. Udgivelsesdato: 2007-Nov...... distress was associated with the sex ratio in the offspring. METHODS: From 1989 to 1992, a cohort of 8,719 Danish-speaking pregnant women were followed until delivery. Questionnaires were administered to the women in early pregnancy and 6,629 (76%) completed the 30-item version of the General Health...

Equivalence ratio and constriction effects on RBCC thrust augmentation

Science.gov (United States)

Koupriyanov, M.; Etele, J.

2011-06-01

A theoretical analysis of a variable area rocket based combined cycle engine with and without simultaneous mixing and combustion is presented. The flowfield is solved using a steady, quasi-one-dimensional, inviscid control volume formulation with combustion effects included via a generalized equilibrium calculation. Compression augmentation is shown to be sensitive to the equivalence ratio within the primary rocket chamber, where ejector section performance is greatest at both low and high equivalence ratios but near a minimum at stoichiometric conditions. The thrust generated by the RBCC engine compared to that generated by the same rocket in isolation can be increased by as much as 12% at constriction ratios of between 45% and 50%. Thrust augmentation is also shown to vary with equivalence ratio, where for a fixed geometry the maximum thrust is generated at equivalence ratios slightly below unity.

Statistical validity of using ratio variables in human kinetics research.

Science.gov (United States)

Liu, Yuanlong; Schutz, Robert W

2003-09-01

The purposes of this study were to investigate the validity of the simple ratio and three alternative deflation models and examine how the variation of the numerator and denominator variables affects the reliability of a ratio variable. A simple ratio and three alternative deflation models were fitted to four empirical data sets, and common criteria were applied to determine the best model for deflation. Intraclass correlation was used to examine the component effect on the reliability of a ratio variable. The results indicate that the validity, of a deflation model depends on the statistical characteristics of the particular component variables used, and an optimal deflation model for all ratio variables may not exist. Therefore, it is recommended that different models be fitted to each empirical data set to determine the best deflation model. It was found that the reliability of a simple ratio is affected by the coefficients of variation and the within- and between-trial correlations between the numerator and denominator variables. It was recommended that researchers should compute the reliability of the derived ratio scores and not assume that strong reliabilities in the numerator and denominator measures automatically lead to high reliability in the ratio measures.

Extraordinary sex ratios: cultural effects on ecological consequences.

Directory of Open Access Journals (Sweden)

Ferenc Molnár

Full Text Available We model sex-structured population dynamics to analyze pairwise competition between groups differing both genetically and culturally. A sex-ratio allele is expressed in the heterogametic sex only, so that assumptions of Fisher's analysis do not apply. Sex-ratio evolution drives cultural evolution of a group-associated trait governing mortality in the homogametic sex. The two-sex dynamics under resource limitation induces a strong Allee effect that depends on both sex ratio and cultural trait values. We describe the resulting threshold, separating extinction from positive growth, as a function of female and male densities. When initial conditions avoid extinction due to the Allee effect, different sex ratios cannot coexist; in our model, greater female allocation always invades and excludes a lesser allocation. But the culturally transmitted trait interacts with the sex ratio to determine the ecological consequences of successful invasion. The invading female allocation may permit population persistence at self-regulated equilibrium. For this case, the resident culture may be excluded, or may coexist with the invader culture. That is, a single sex-ratio allele in females and a cultural dimorphism in male mortality can persist; a low-mortality resident trait is maintained by father-to-son cultural transmission. Otherwise, the successfully invading female allocation excludes the resident allele and culture and then drives the population to extinction via a shortage of males. Finally, we show that the results obtained under homogeneous mixing hold, with caveats, in a spatially explicit model with local mating and diffusive dispersal in both sexes.

THEORETICAL PROPOSAL FOR EXPANSION OF ROE WITH NEW SUB-RATIOS

Directory of Open Access Journals (Sweden)

Danilo Dorović

2017-09-01

Full Text Available ROE is the ratio of profitability which can be separated into three ratios in Du Pont model. The question is - can it be even more comprehensive with more than three Du Pont ratios; that is can it also include liquidity, market share, break-even point, plan vs. actual, structure of assets and liabilities, structure of fixed costs, etc.? If these can be included in calculation, the financial, management accounting and strategic analysis could be more integrated into one more rounded system. Financial ratio analysis would also integrate into one ratio the usually different areas of analysis, like structure of assets, structure of liabili-ties, liquidity, turnover, financial leverage, etc. Strategic management and management accounting ratios, developed in the literature and used in business practice, are represented. The article in front of you presents a theoretical proposal through deduction method of how mentioned measures can potentially be included in ROE, resulting in potential benefits in planning and controlling. Integrated different areas of financial ratio analysis, manage- ment accounting and strategic analysis each represented with its ratios in profitability measure ratio, provides potentially better view of conditions, profit multiplicators and risk the profitability is achieved by. Integration inside profitability measure gives a special qual-itative advantage, having in mind that achieved profit is the main goal for owners of the company`s equity.

Sex ratios in fetuses and liveborn infants with autosomal aneuploidy

Energy Technology Data Exchange (ETDEWEB)

Heuther, C.A.; Martin, R.L.M.; Stoppelman, S.M. [Univ. of Cincinnati, OH (United States)] [and others

1996-06-14

Ten data sources were used substantially to increase the available data for estimating fetal and livebirth sex ratios for Patau (trisomy 13), Edwards (trisomy 18), and Down (trisomy 21) syndromes and controls. The fetal sex ratio estimate was 0.88 (N = 584) for trisomy 13, 0.90 (N = 1702) for trisomy 18, and 1.16 (N = 3154) for trisomy 21. All were significantly different from prenatal controls (1.07). The estimated ratios in prenatal controls were 1.28 (N = 1409) for CVSs and 1.06 (N = 49427) for amniocenteses, indicating a clear differential selection against males, mostly during the first half of fetal development. By contrast, there were no sex ratio differences for any of the trisomies when comparing gestational ages <16 and >16 weeks. The livebirth sex ratio estimate was 0.90 (N = 293) for trisomy 13, 0.63 (N = 497) for trisomy 18, and 1.15 (N = 6424) for trisomy 21, the latter two being statistically different than controls (1.05) (N = 3660707). These ratios for trisomies 13 and 18 were also statistically different than the ratio for trisomy 21. Only in trisomy 18 did the sex ratios in fetuses and livebirths differ, indicating a prenatal selection against males >16 weeks. No effects of maternal age or race were found on these estimates for any of the fetal or livebirth trisomies. Sex ratios for translocations and mosaics were also estimated for these aneuploids. Compared to previous estimates, these results are less extreme, most likely because of larger sample sizes and less sample bias. They support the hypothesis that these trisomy sex ratios are skewed at conception, or become so during embryonic development through differential intrauterine selection. The estimate for Down syndrome livebirths is also consistent with the hypothesis that its higher sex ratio is associated with paternal nondisjunction. 36 refs., 5 tabs.

Transport in a small aspect ratio torus

International Nuclear Information System (INIS)

White, R.B.; Gates, D.A.; Mynick, H.E.

2005-01-01

Transport theory in toroidal devices often assumes large aspect ratio and also assumes the poloidal field is small compared to the toroidal field. These assumptions result in transport which in the low collision rate limit is dominated by banana orbits, giving the largest collisionless excursion of a particle from an initial flux surface. However in a small aspect ratio device the gyro radius may be larger than the banana excursion, resulting in significant deviations from the standard neoclassical predictions. In this paper we report numerical simulation of diffusion in low and high beta low aspect ratio equilibria. We also sketch an analytic theory. The diffusion, which we refer to as omniclassical, is a combination of neoclassical and properly averaged classical effects, and can be two or three times the neoclassical value. Good agreement of the analytic theory with numerical simulations is obtained. (author)

D/H ratios of the inner Solar System.

Science.gov (United States)

Hallis, L J

2017-05-28

The original hydrogen isotope (D/H) ratios of different planetary bodies may indicate where each body formed in the Solar System. However, geological and atmospheric processes can alter these ratios through time. Over the past few decades, D/H ratios in meteorites from Vesta and Mars, as well as from S- and C-type asteroids, have been measured. The aim of this article is to bring together all previously published data from these bodies, as well as the Earth, in order to determine the original D/H ratio for each of these inner Solar System planetary bodies. Once all secondary processes have been stripped away, the inner Solar System appears to be relatively homogeneous in terms of water D/H, with the original water D/H ratios of Vesta, Mars, the Earth, and S- and C-type asteroids all falling between δD values of -100‰ and -590‰. This homogeneity is in accord with the 'Grand tack' model of Solar System formation, where giant planet migration causes the S- and C-type asteroids to be mixed within 1 AU to eventually form the terrestrial planets.This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'. © 2017 The Authors.

Accurate isotope ratio mass spectrometry. Some problems and possibilities

International Nuclear Information System (INIS)

Bievre, P. de

1978-01-01

The review includes reference to 190 papers, mainly published during the last 10 years. It covers the following: important factors in accurate isotope ratio measurements (precision and accuracy of isotope ratio measurements -exemplified by determinations of 235 U/ 238 U and of other elements including 239 Pu/ 240 Pu; isotope fractionation -exemplified by curves for Rb, U); applications (atomic weights); the Oklo natural nuclear reactor (discovered by UF 6 mass spectrometry at Pierrelatte); nuclear and other constants; isotope ratio measurements in nuclear geology and isotope cosmology - accurate age determination; isotope ratio measurements on very small samples - archaeometry; isotope dilution; miscellaneous applications; and future prospects. (U.K.)

Ratio Bias and Policy Preferences

DEFF Research Database (Denmark)

Pedersen, Rasmus Tue

2016-01-01

Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...

Radioactive anomaly discrimination from spectral ratios

Science.gov (United States)

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.

GUT Scale Fermion Mass Ratios

International Nuclear Information System (INIS)

Spinrath, Martin

2014-01-01

We present a series of recent works related to group theoretical factors from GUT symmetry breaking which lead to predictions for the ratios of quark and lepton Yukawa couplings at the unification scale. New predictions for the GUT scale ratios y μ /y s , y τ /y b and y t /y b in particular are shown and compared to experimental data. For this comparison it is important to include possibly large supersymmetric threshold corrections. Due to this reason the structure of the fermion masses at the GUT scale depends on TeV scale physics and makes GUT scale physics testable at the LHC. We also discuss how this new predictions might lead to predictions for mixing angles by discussing the example of the recently measured last missing leptonic mixing angle θ 13 making this new class of GUT models also testable in neutrino experiments

Investigation into stutter ratio variability between different laboratories.

Science.gov (United States)

Bright, Jo-Anne; Curran, James M

2014-11-01

The determination of parameters such as stutter ratio is important to inform a laboratory's forensic DNA profile interpretation strategy. As part of a large data analysis project to implement a continuous model of DNA profile interpretation we analysed stutter ratio data from eight different forensic laboratories for the Promega PowerPlex(®) 21 multiplex. This allowed a comparison of inter laboratory variation. The maximum difference for any one laboratory from the average of the best fit determined by the model was 0.31%. These results indicate that stutter ratios calculated from samples analysed using the same profiling kit are not expected to differ between laboratories, even those using different capillary electrophoresis platforms. A common set of laboratory parameters are able to be generated and used for profile interpretation at all laboratories using the same multiplex and cycle number, potentially reducing the need for individual laboratories to determine stutter ratios. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

India's Distorted Sex Ratio: Dire Consequences for Girls.

Science.gov (United States)

Roberts, Lisa R; Montgomery, Susanne B

2016-01-01

Female gender discrimination related to cultural preference for males is a common global problem, especially in Asian countries. Numerous laws intended to prevent discrimination on the basis of gender have been passed in India, yet the distorted female-to-male sex ratio seems to show worsening tendencies. Using detailed, two-year longitudinal chart abstraction data about delivery records of a private mission hospital in rural India, we explored if hospital birth ratio data differed in comparison to regional data, and what demographic and contextual variables may have influenced these outcomes. Using quantitative chart abstraction and qualitative contextual data, study results showed the female-to-male ratio was lower than the reported state ratio at birth. In the context of India's patriarchal structure, with its strong son preference, women are under tremendous pressure or coerced to access community-based, sex-selective identification and female fetus abortion. Nurses may be key to turning the tide.

Ratio index variables or ANCOVA? Fisher's cats revisited.

Science.gov (United States)

Tu, Yu-Kang; Law, Graham R; Ellison, George T H; Gilthorpe, Mark S

2010-01-01

Over 60 years ago Ronald Fisher demonstrated a number of potential pitfalls with statistical analyses using ratio variables. Nonetheless, these pitfalls are largely overlooked in contemporary clinical and epidemiological research, which routinely uses ratio variables in statistical analyses. This article aims to demonstrate how very different findings can be generated as a result of less than perfect correlations among the data used to generate ratio variables. These imperfect correlations result from measurement error and random biological variation. While the former can often be reduced by improvements in measurement, random biological variation is difficult to estimate and eliminate in observational studies. Moreover, wherever the underlying biological relationships among epidemiological variables are unclear, and hence the choice of statistical model is also unclear, the different findings generated by different analytical strategies can lead to contradictory conclusions. Caution is therefore required when interpreting analyses of ratio variables whenever the underlying biological relationships among the variables involved are unspecified or unclear. (c) 2009 John Wiley & Sons, Ltd.

Inter-Annual Variability of Fledgling Sex Ratio in King Penguins.

Directory of Open Access Journals (Sweden)

Célia Bordier

Full Text Available 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.

Inter-Annual Variability of Fledgling Sex Ratio in King Penguins.

Science.gov (United States)

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.

Digit ratios, the menstrual cycle and social preferences

NARCIS (Netherlands)

Buser, T.

2012-01-01

We examine whether social preferences are partially determined by biological factors. We do this by investigating whether digit ratios (2D:4D) and menstrual cycle information are correlated with choices in ultimatum, trust, public good and dictator games. Digit ratios are thought to be a proxy for

Risk aversion vs. the Omega ratio : Consistency results

NARCIS (Netherlands)

Balder, Sven; Schweizer, Nikolaus

This paper clarifies when the Omega ratio and related performance measures are consistent with second order stochastic dominance and when they are not. To avoid consistency problems, the threshold parameter in the ratio should be chosen as the expected return of some benchmark – as is commonly done

Likelihood-ratio-based biometric verification

NARCIS (Netherlands)

Bazen, A.M.; Veldhuis, Raymond N.J.

2002-01-01

This paper presents results on optimal similarity measures for biometric verification based on fixed-length feature vectors. First, we show that the verification of a single user is equivalent to the detection problem, which implies that for single-user verification the likelihood ratio is optimal.

Likelihood Ratio-Based Biometric Verification

NARCIS (Netherlands)

Bazen, A.M.; Veldhuis, Raymond N.J.

The paper presents results on optimal similarity measures for biometric verification based on fixed-length feature vectors. First, we show that the verification of a single user is equivalent to the detection problem, which implies that, for single-user verification, the likelihood ratio is optimal.

SM Higgs decay branching ratios and total Higgs width

CERN Multimedia

Daniel Denegri

2001-01-01

Upper: Higgs decay ratios as a function of Higgs mass. The largest branching ratio is not necessarily the most usefull one. The most usefull ones are gamma gamma bbar ZZ and WW as in those modes latter signal to background ratios can be achieved. Lower: Total Higgs decay width versus Higgs mass. At low masses the natural width is extremely small, thus observability depends on instrumental resolution primarily.

Method of Poisson's ratio imaging within a material part

Science.gov (United States)

Roth, Don J. (Inventor)

1996-01-01

The present invention is directed to a method of displaying the Poisson's ratio image of a material part. In the present invention longitudinal data is produced using a longitudinal wave transducer and shear wave data is produced using a shear wave transducer. The respective data is then used to calculate the Poisson's ratio for the entire material part. The Poisson's ratio approximations are then used to displayed the image.

Yearbook sectoral financial ratios in mexico for business benchmarking

Directory of Open Access Journals (Sweden)

Deyanira Bernal Domínguez

2012-05-01

Full Text Available Financial analysis through ratios is a useful tool for improving organizational performance. Databases of financial information in Mexico are limited, therefore the importance of an annual publication of financial ratios per company and industry average. The objectives of this research are: describe the financial ratios with higher predictive potential and their formulas, as well as the design of a research instrument for measuring the relevance of the publication. A descriptive methodology was applied selecting through the analysis ofempirical studies, several ratios of liquidity, leverage, asset management, business cycle, performance and self-financing. The questionnaire contains 43 reagents to be applied to a statistically representative sample of 46 entrepreneurs in Culiacan, Sinaloa, Mexico.

Asymmetric Lévy flight in financial ratios.

Science.gov (United States)

Podobnik, Boris; Valentinčič, Aljoša; Horvatić, Davor; Stanley, H Eugene

2011-11-01

Because financial crises are characterized by dangerous rare events that occur more frequently than those predicted by models with finite variances, we investigate the underlying stochastic process generating these events. In the 1960s Mandelbrot [Mandelbrot B (1963) J Bus 36:394-419] and Fama [Fama EF (1965) J Bus 38:34-105] proposed a symmetric Lévy probability distribution function (PDF) to describe the stochastic properties of commodity changes and price changes. We find that an asymmetric Lévy PDF, L, characterized by infinite variance, models several multiple credit ratios used in financial accounting to quantify a firm's financial health, such as the Altman [Altman EI (1968) J Financ 23:589-609] Z score and the Zmijewski [Zmijewski ME (1984) J Accounting Res 22:59-82] score, and models changes of individual financial ratios, ΔX(i). We thus find that Lévy PDFs describe both the static and dynamics of credit ratings. We find that for the majority of ratios, ΔX(i) scales with the Lévy parameter α ≈ 1, even though only a few of the individual ratios are characterized by a PDF with power-law tails X(i)(-1-α) with infinite variance. We also find that α exhibits a striking stability over time. A key element in estimating credit losses is the distribution of credit rating changes, the functional form of which is unknown for alphabetical ratings. For continuous credit ratings, the Altman Z score, we find that P(ΔZ) follows a Lévy PDF with power-law exponent α ≈ 1, consistent with changes of individual financial ratios. Estimating the conditional P(ΔZ|Z) versus Z, we demonstrate how this continuous credit rating approach and its dynamics can be used to evaluate credit risk.

Measurements of K/Π ratio in cosmic radiation

International Nuclear Information System (INIS)

Mahon, J.R.P.

1986-01-01

Measurements of k/Π ratio in cosmic radiation by its half lives and its fluxes, were carried out. The kaon flux was obtained using the Cherenkov detector, and for pion flux scintillation detectors were used. The final results of K/Π ratio ∼ 0.2 was obtained. (M.C.K.) [pt

Financial Ratio and Its Influence to Profitability in Islamic Banks.

Directory of Open Access Journals (Sweden)

Erika Amelia

2015-10-01

Full Text Available This research aims to analyze the influence of the Capital Adequacy Ratio (CAR, Non Performing Financing (NPF, Financing to Deposit Ratio (FDR and Biaya Operasional Pendapatan Operasional (BOPO to Return on Asset (ROA in Bank Muamalat Indonesia and Bank Syariah Mega. The data analysis method used in this research is multiple regression analysis. From the test results show that the Capital Adequacy Ratio (CAR, Non Performing Financing (NPF, Financing to Deposit Ratio (FDR and Biaya Operasional Pendapatan Operasional (BOPO simultaneously effect to Return on Asset (ROA. Based on the test results of the t statistic was concluded that the Capital Adequacy Ratio (CAR, Non Performing Financing (NPF and the Financing to Deposit Ratio (FDR partially no significant effect to Return on Asset (ROA, while Biaya Operasional Pendapatan Operasional (BOPO partially significant effect to Return on Asset (ROADOI: 10.15408/aiq.v7i2.1700

Nondestructive measurement of the grid ratio using a single image

International Nuclear Information System (INIS)

Pasciak, A. S.; Jones, A. Kyle

2009-01-01

The antiscatter grid is an essential part of modern radiographic systems. Since the introduction of the antiscatter grid, however, there have been few methods proposed for acceptance testing and verification of manufacturer-supplied grid specifications. The grid ratio (r) is an important parameter describing the antiscatter grid because it affects many other grid quality metrics, such as the contrast improvement ratio (K), primary transmission (T p ), and scatter transmission (T s ). Also, the grid ratio in large part determines the primary clinical use of the grid. To this end, the authors present a technique for the nondestructive measurement of the grid ratio of antiscatter grids. They derived an equation that can be used to calculate the grid ratio from a single off-focus flat field image by exploiting the relationship between grid cutoff and off-focus distance. The calculation can be performed by hand or with included analysis software. They calculated the grid ratios of several different grids throughout the institution, and afterward they destructively measured the grid ratio of a nominal r8 grid previously evaluated with the method. They also studied the sensitivity of the method to technical factors and choice of parameters. With one exception, the results for the grids found in the institution were in agreement with the manufacturer's specifications and international standards. The nondestructive evaluation of the r8 grid indicated a ratio of 7.3, while the destructive measurement indicated a ratio of 7.53±0.28. Repeated evaluations of the same grid yielded consistent results. The technique provides the medical physicist with a new tool for quantitative evaluation of the grid ratio, an important grid performance criterion. The method is robust and repeatable when appropriate choices of technical factors and other parameters are made.

The human heart: application of the golden ratio and angle.

Science.gov (United States)

Henein, Michael Y; Zhao, Ying; Nicoll, Rachel; Sun, Lin; Khir, Ashraf W; Franklin, Karl; Lindqvist, Per

2011-08-04

The golden ratio, or golden mean, of 1.618 is a proportion known since antiquity to be the most aesthetically pleasing and has been used repeatedly in art and architecture. Both the golden ratio and the allied golden angle of 137.5° have been found within the proportions and angles of the human body and plants. In the human heart we found many applications of the golden ratio and angle, in addition to those previously described. In healthy hearts, vertical and transverse dimensions accord with the golden ratio, irrespective of different absolute dimensions due to ethnicity. In mild heart failure, the ratio of 1.618 was maintained but in end-stage heart failure the ratio significantly reduced. Similarly, in healthy ventricles mitral annulus dimensions accorded with the golden ratio, while in dilated cardiomyopathy and mitral regurgitation patients the ratio had significantly reduced. In healthy patients, both the angles between the mid-luminal axes of the pulmonary trunk and the ascending aorta continuation and between the outflow tract axis and continuation of the inflow tract axis of the right ventricle approximate to the golden angle, although in severe pulmonary hypertension, the angle is significantly increased. Hence the overall cardiac and ventricular dimensions in a normal heart are consistent with the golden ratio and angle, representing optimum pump structure and function efficiency, whereas there is significant deviation in the disease state. These findings could have anatomical, functional and prognostic value as markers of early deviation from normality. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Exploring the possibilities for stabilizing the sex ratio in India

Directory of Open Access Journals (Sweden)

Saurabh RamBihariLal Shrivastava

2015-12-01

Full Text Available The sex ratio is an important demographic indicator for a nation. A wide range of adverse social consequences have been observed because of a skewed sex ratio in India. If India as a nation is to achieve the Millennium Development Goal – 3 (which promotes gender equality and ensures the empowerment of women, the primary target should be involve all those involved, so that a collective and comprehensive approach can be developed to counter the public health menace of an asymmetrical sex ratio. In conclusion, the nation’s program managers should prioritize the issue of a skewed sex ratio and work towards developing a coordinated response.Key Words: Sex ratio, policy makers, India.

The Laplace Likelihood Ratio Test for Heteroscedasticity

Directory of Open Access Journals (Sweden)

J. Martin van Zyl

2011-01-01

Full Text Available It is shown that the likelihood ratio test for heteroscedasticity, assuming the Laplace distribution, gives good results for Gaussian and fat-tailed data. The likelihood ratio test, assuming normality, is very sensitive to any deviation from normality, especially when the observations are from a distribution with fat tails. Such a likelihood test can also be used as a robust test for a constant variance in residuals or a time series if the data is partitioned into groups.

ORTHO-TO-PARA ABUNDANCE RATIO (OPR) OF AMMONIA IN 15 COMETS: OPRs OF AMMONIA VERSUS 14N/15N RATIOS IN CN

International Nuclear Information System (INIS)

Shinnaka, Yoshiharu; Kawakita, Hideyo; Kobayashi, Hitomi; Jehin, Emmanuel; Manfroid, Jean; Hutsemekers, Damien; Arpigny, Claude

2011-01-01

The ortho-to-para abundance ratio (OPR) of cometary molecules is considered to be one of the primordial characteristics of cometary ices. We present OPRs of ammonia (NH 3 ) in 15 comets based on optical high-dispersion spectroscopic observations of NH 2 , which is a photodissociation product of ammonia in the gaseous coma. The observations were mainly carried out with the VLT/UVES. The OPR of ammonia is estimated from the OPR of NH 2 based on the observations of the NH 2 (0, 9, 0) vibronic band. The absorption lines by the telluric atmosphere are corrected and the cometary C 2 emission lines blended with NH 2 lines are removed in our analysis. The ammonia OPRs show a cluster between 1.1 and 1.2 (this corresponds to a nuclear spin temperature of ∼30 K) for all comets in our sample except for 73P/Schwassmann-Wachmann 3 (73P/SW3). Comet 73P/SW3 (both B- and C-fragments) shows the OPR of ammonia consistent with nuclear spin statistical weight ratio (1.0) that indicates a high-temperature limit as nuclear spin temperature. We compared the ammonia OPRs with other properties ( 14 N/ 15 N ratios in CN, D/H ratios of water, and mixing ratios of volatiles). Comet 73P/SW3 is clearly different from the other comets in the plot of ammonia OPRs versus 14 N/ 15 N ratios in CN. The ammonia OPRs of 1.0 and lower 15 N-fractionation of CN in comet 73P/SW3 imply that icy materials in this comet formed under warmer conditions than other comets. Comets may be classified into two groups in the plot of ammonia OPRs against 14 N/ 15 N ratios in CN.

Surface area-volume ratios in insects.

Science.gov (United States)

Kühsel, Sara; Brückner, Adrian; Schmelzle, Sebastian; Heethoff, Michael; Blüthgen, Nico

2017-10-01

Body mass, volume and surface area are important for many aspects of the physiology and performance of species. Whereas body mass scaling received a lot of attention in the literature, surface areas of animals have not been measured explicitly in this context. We quantified surface area-volume (SA/V) ratios for the first time using 3D surface models based on a structured light scanning method for 126 species of pollinating insects from 4 orders (Diptera, Hymenoptera, Lepidoptera, and Coleoptera). Water loss of 67 species was measured gravimetrically at very dry conditions for 2 h at 15 and 30 °C to demonstrate the applicability of the new 3D surface measurements and relevance for predicting the performance of insects. Quantified SA/V ratios significantly explained the variation in water loss across species, both directly or after accounting for isometric scaling (residuals of the SA/V ∼ mass 2/3 relationship). Small insects with a proportionally larger surface area had the highest water loss rates. Surface scans of insects to quantify allometric SA/V ratios thus provide a promising method to predict physiological responses, improving the potential of body mass isometry alone that assume geometric similarity. © 2016 Institute of Zoology, Chinese Academy of Sciences.

Mean centering of ratio spectra and successive derivative ratio spectrophotometric methods for determination of isopropamide iodide, trifluoperazine hydrochloride and trifluoperazine oxidative degradate

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Maha M. Abdelrahman

2016-09-01

Full Text Available Two sensitive, selective and precise stability indicating methods for the determination of isopropamide iodide (ISO, trifluoperazine hydrochloride (TPZ and trifluoperazine oxidative degradate (DEG were developed and validated. Method A is a successive derivative ratio spectrophotometric one, which depends on the successive derivative of ratio spectra in two steps using 0.1 N HCl as a solvent and measuring TPZ at 250.4 and 257.2 nm, ISO at 223 and 228 nm and DEG at 210.6, 213 and 270.2 nm. Method B is mean centering of ratio spectra which depends on using the mean centered ratio spectra in two successive steps and measuring the mean centered values of the second ratio spectra at 322, 355 and 339 nm for TPZ, ISO and DEG, respectively. Factors affecting the developed methods were studied and optimized, moreover, they have been validated as per ICH guidelines and the results demonstrated that the suggested methods are reliable, reproducible and suitable for routine use with short analysis time. Statistical analysis of the two developed methods with the reported one using F- and Student’s t-test showed no significant difference regarding accuracy and precision.

Patterns of Family Formation in Response to Sex Ratio Variation.

Science.gov (United States)

Schacht, Ryan; Kramer, Karen L

2016-01-01

The impact that unbalanced sex ratios have on health and societal outcomes is of mounting contemporary concern. However, it is increasingly unclear whether it is male- or female-biased sex ratios that are associated with family and social instability. From a socio-demographic perspective, male-biased sex ratios leave many men unable to find a mate, elevating competition among males, disrupting family formation and negatively affecting social stability. In contrast, from a mating-market perspective, males are expected to be less willing to marry and commit to a family when the sex ratio is female-biased and males are rare. Here we use U.S. data to evaluate predictions from these competing frameworks by testing the relationship between the adult sex ratio and measures of family formation. We find that when women are rare men are more likely to marry, be part of a family and be sexually committed to a single partner. Our results do not support claims that male-biased sex ratios lead to negative family outcomes due to a surplus of unmarried men. Rather, our results highlight the need to pay increased attention to female-biased sex ratios.

Analysis of cash flow ratios: A study on CMC

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Somnath Das

2018-01-01

Full Text Available Cash flow ratios help financial users get relevant information about financial resources for a given time. Cash flow ratios are now used more than the traditional ones because it is more effective and justified. Cash flow based ratios are especially surprising because they do not only play a significant role in the credit rating of evaluation, but also forecast the failure of a corporation. In this study, we perform an empirical investigation on a company named CMC. From the study, it is clear that the liquidity and solvency positions of the company were moderate whereas the company maintained low profitability. On the other hand, the efficiency and sufficiency ratios of the study give us a new look on financial judgement.

Mixing ratios of carbon monoxide in the troposphere

Energy Technology Data Exchange (ETDEWEB)

Novelli, P.C.; Steele, L.P. (Univ. of Colorado, Boulder (United States)); Tans, P.P. (NOAA, Boulder, CO (United States))

1992-12-20

Carbon monoxide (CO) mixing ratios were measured in air samples collected weekly at eight locations. The air was collected as part of the CMDL/NOAA cooperative flask sampling program (Climate Monitoring and Diagnostics Laboratory, formerly Geophysical Monitoring for Climatic Change, Air Resources Laboratory/National Oceanic and Atmospheric Administration) at Point Barrow, Alaska, Niwot Ridge, Colorado, Mauna Loa and Cape Kumakahi, Hawaii, Guam, Marianas Islands, Christmas Island, Ascension Island and American Samoa. Half-liter or 3-L glass flasks fitted with glass piston stopcocks holding teflon O rings were used for sample collection. CO levels were determined within several weeks of collection using gas chromatography followed by mercuric oxide reduction detection, and mixing ratios were referenced against the CMDL/NOAA carbon monoxide standard scale. During the period of study (mid-1988 through December 1990) CO levels were greatest in the high latitudes of the northern hemisphere (mean mixing ratio from January 1989 to December 1990 at Point Barrow was approximately 154 ppb) and decreased towards the south (mean mixing ratio at Samoa over a similar period was 65 ppb). Mixing ratios varied seasonally, the amplitude of the seasonal cycle was greatest in the north and decreased to the south. Carbon monoxide levels were affected by both local and regional scale processes. The difference in CO levels between northern and southern latitudes also varied seasonally. The greatest difference in CO mixing ratios between Barrow and Samoa was observed during the northern winter (about 150 ppb). The smallest difference, 40 ppb, occurred during the austral winter. The annually averaged CO difference between 71[degrees]N and 14[degrees]S was approximately 90 ppb in both 1989 and 1990; the annually averaged interhemispheric gradient from 71[degrees]N to 41[degrees]S is estimated as approximately 95 ppb. 66 refs., 5 figs., 5 tabs.

Cold versus hot fusion deuterium branching ratios

International Nuclear Information System (INIS)

Fox, H.; Bass, R.

1995-01-01

A major source of misunderstanding of the nature of cold nuclear fusion has been the expectation that the deuterium branching ratios occurring within a palladium lattice would be consistent with the gas-plasma branching ratios. This misunderstanding has led to the concept of the dead graduate student, the 1989's feverish but fruitless search for neutron emissions from cold fusion reactors, and the follow-on condemnation of the new science of cold fusion. The experimental facts are that in a properly loaded palladium lattice, the deuterium fusion produces neutrons at little above background, a greatly less-than-expected production of tritium (the tritium desert), and substantially more helium-4 than is observed in hot plasma physics. The experimental evidence is now compelling (800 reports of success from 30 countries) that cold nuclear fusion is a reality, that the branching ratios are unexpected, and that a new science is struggling to be recognized. Commercialization of some types of cold fusion devices has already begun

Odor concentration invariance by chemical ratio coding

Directory of Open Access Journals (Sweden)

Naoshige Uchida

2008-08-01

Full Text Available Many animal species rely on chemical signals to extract ecologically important information from the environment. Yet in natural conditions chemical signals will frequently undergo concentration changes that produce differences in both level and pattern of activation of olfactory receptor neurons. Thus, a central problem in olfactory processing is how the system is able to recognize the same stimulus across different concentrations. To signal species identity for mate recognition, some insects use the ratio of two components in a binary chemical mixture to produce a code that is invariant to dilution. Here, using psychophysical methods, we show that rats also classify binary odor mixtures according to the molar ratios of their components, spontaneously generalizing over at least a tenfold concentration range. These results indicate that extracting chemical ratio information is not restricted to pheromone signaling and suggest a general solution for concentration-invariant odor recognition by the mammalian olfactory system.

Worldwide lead-isotope ratio in bivalves and sediments

DEFF Research Database (Denmark)

Larsen, Martin Mørk; Jacobsen, Gitte; Strand, Jakob

The lead-isotope ratio have been used to assess and identify impact of leaded gasoline, coal combustion and  mineral activities[ref 1] due to the difference in 206Pb (~52%), 207Pb (~24%) and 208Pb (~23%) isotope ratios. The source of these differences is the decaying of the parent isotopes of 238U...

THE ENIGMA OF ETHIOPIAN SEX RATIOS AT BIRTH.

Science.gov (United States)

Garenne, Michel

2017-09-01

This study analysed sex ratios at birth (defined as the number of male births per 100 female births) using data on children ever-born from three censuses conducted in Ethiopia in 1984, 1994 and 2007. The results showed very high values by any standard, with an average of 108.4 for a sample of some 8.2 million births, with somewhat lower values in urban areas. Analysis of socioeconomic correlates revealed that the sex ratio varied very much by household wealth, from about 110 for very poor women to about 102 for wealthier women. The high value of the sex ratio at birth in Ethiopia could be explained by poverty, used as a proxy for poor nutritional status. In multivariate analysis, the effects of living in urban areas and of maternal education were less important than household wealth. Among the many ethno-linguistic groups, the Nilotic family had higher sex ratios than other groups. The results were confirmed using data from DHS surveys conducted in the country, and by the analysis of children still living at time of census.

BENEFITS AND CHALLENGES OF VARIABLE COMPRESSION RATIO AT DIESEL ENGINES

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Radivoje B Pešić

2010-01-01

Full Text Available The compression ratio strongly affects the working process and provides an exceptional degree of control over engine performance. In conventional internal combustion engines, the compression ratio is fixed and their performance is therefore a compromise between conflicting requirements. One fundamental problem is that drive units in the vehicles must successfully operate at variable speeds and loads and in different ambient conditions. If a diesel engine has a fixed compression ratio, a minimal value must be chosen that can achieve a reliable self-ignition when starting the engine in cold start conditions. In diesel engines, variable compression ratio provides control of peak cylinder pressure, improves cold start ability and low load operation, enabling the multi-fuel capability, increase of fuel economy and reduction of emissions. This paper contains both theoretical and experimental investigation of the impact that automatic variable compression ratios has on working process parameters in experimental diesel engine. Alternative methods of implementing variable compression ratio are illustrated and critically examined.

Explorations in statistics: the analysis of ratios and normalized data.

Science.gov (United States)

Curran-Everett, Douglas

2013-09-01

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 proportion for some biological response or to derive some standardized variable. In each situation, we want to control for differences in the denominator when the thing we really care about is the numerator. But there is peril lurking in a ratio: only if the relationship between numerator and denominator is a straight line through the origin will the ratio be meaningful. If not, the ratio will misrepresent the true relationship between numerator and denominator. In contrast, regression techniques-these include analysis of covariance-are versatile: they can accommodate an analysis of the relationship between numerator and denominator when a ratio is useless.

RECENT TRENDS IN GENDER RATIO AT BIRTH IN HANGZHOU, CHINA.

Science.gov (United States)

Tang, L; Qiu, L Q; Yau, Kkw; Hui, Y V; Binns, C W; Lee, A H

2015-12-01

Higher than normal sex ratios at birth in China have been reported since the early 1980's. This study aimed to investigate recent trends in sex ratio at birth in Hangzhou, capital of Zhejiang Province in southeast China. Information on selected maternal and birth-related characteristics was extracted from the Hangzhou Birth Information Database for all pregnant women who delivered live births during 2005-2014. The sex ratios at birth were calculated after excluding infants with missing data on gender and those born with ambiguous genitalia. A total of 478,192 male births and 430,852 female births were recorded giving an overall ratio of 111.0. The sex ratio at birth was almost constant at around 110.7 during the period 2005-2008, followed by an increase to the peak at 113.1 in 2010 and then declined back to 109.6 in 2014. The gender ratio at birth in Hangzhou remained unbalanced for the past decade.

Ratios of charmed and bottom meson decay constants

International Nuclear Information System (INIS)

Oakes, R.J.

1994-01-01

It is shown that general features of the standard theory require the double ratio (f Bs /f Bd )/(f Ds /f Dd ) to be very nearly unity with only very small corrections. The ratios f Bs /f Bd and f Ds /f Dd are both also near unity, within small corrections which partially cancel in the double ratio. A precise measurement of f Ds /f Dd therefore provides a sensitive test of some generally accepted features of the standard Lagrangian, as well as determines the value of f Bs /f Bd , which is important for calculating the relative strengths of B s- bar B s and B d- bar B d mixing

Lagoa Real design. Cachoeira mine. Uranium ratio from gamma profile

International Nuclear Information System (INIS)

Juliao, B.

1984-06-01

This paper presents the satisfactory accuracy of uranium ratio from gamma profile, using an equation from simple regression. The comparative study between radiometric ratios calculated from gamma data in boreholes and uranium ratio determined by Delayed Neutron Analysis shows a good measure of correlation in Cachoeira Mines. (author)

The golden ratio in Schwarzschild-Kottler black holes

Energy Technology Data Exchange (ETDEWEB)

Cruz, Norman [Universidad de Santiago de Chile, Departamento de Fisica, Facultad de Ciencia, Santiago 2 (Chile); Olivares, Marco [Universidad Diego Portales, Facultad de Ingenieria, Santiago (Chile); Villanueva, J.R. [Universidad de Valparaiso, Instituto de Fisica y Astronomia, Valparaiso (Chile)

2017-02-15

In this paper we show that the golden ratio is present in the Schwarzschild-Kottler metric. For null geodesics with maximal radial acceleration, the turning points of the orbits are in the golden ratio Φ = (√(5)-1)/2. This is a general result which is independent of the value and sign of the cosmological constant Λ. (orig.)

The reaction index and positivity ratio revisited

DEFF Research Database (Denmark)

Andersen, Klaus Ejner; Andersen, Flemming

2008-01-01

BACKGROUND AND OBJECTIVES: Assessing the quality of patch test preparations continues to be a challenge. 2 parameters, the reaction index (RI) and positivity ratio (PR), have been proposed as quality indicators by the Information Network of Departments of Dermatology (IVDK). The value of these st......BACKGROUND AND OBJECTIVES: Assessing the quality of patch test preparations continues to be a challenge. 2 parameters, the reaction index (RI) and positivity ratio (PR), have been proposed as quality indicators by the Information Network of Departments of Dermatology (IVDK). The value...

MAGNESIUM ISOTOPE RATIOS IN ω CENTAURI RED GIANTS

International Nuclear Information System (INIS)

Da Costa, G. S.; Norris, John E.; Yong, David

2013-01-01

We have used the high-resolution observations obtained at the Anglo-Australian Telescope with Ultra-High Resolution Facility (R ∼ 100,000) and at Gemini-S with b-HROS (R ∼ 150,000) to determine magnesium isotope ratios for seven ω Cen red giants that cover a range in iron abundance from [Fe/H] = –1.78 to –0.78 dex, and for two red giants in M4 (NGC 6121). The ω Cen stars sample both the ''primordial'' (i.e., O-rich, Na- and Al-poor) and the ''extreme'' (O-depleted, Na- and Al-rich) populations in the cluster. The primordial population stars in both ω Cen and M4 show ( 25 Mg, 26 Mg)/ 24 Mg isotopic ratios that are consistent with those found for the primordial population in other globular clusters with similar [Fe/H] values. The isotopic ratios for the ω Cen extreme stars are also consistent with those for extreme population stars in other clusters. The results for the extreme population stars studied indicate that the 26 Mg/ 24 Mg ratio is highest at intermediate metallicities ([Fe/H] 26 Mg in the extreme population stars is notably higher than that of 25 Mg, in contrast to model predictions. The 25 Mg/ 24 Mg isotopic ratio in fact does not show any obvious dependence on either [Fe/H] or [Al/Fe] nor, intriguingly, any obvious difference between the primordial and extreme population stars.

National, regional, and global sex ratios of infant, child, and under-5 mortality and identification of countries with outlying ratios: a systematic assessment

OpenAIRE

Alkema, Leontine; Chao, Fengqing; You, Danzhen; Pedersen, Jon; Sawyer, Cheryl C

2014-01-01

Background: Under natural circumstances, the sex ratio of male to female mortality up to the age of 5 years is greater than one but sex discrimination can change sex ratios. The estimation of mortality by sex and identification of countries with outlying levels is challenging because of issues with data availability and quality, and because sex ratios might vary naturally based on differences in mortality levels and associated cause of death distributions. Methods: For this systematic anal...

Asthma Medication Ratio Predicts Emergency Depart...

Data.gov (United States)

U.S. Department of Health & Human Services — According to findings reported in Asthma Medication Ratio Predicts Emergency Department Visits and Hospitalizations in Children with Asthma, published in Volume 3,...

Second to fourth digit ratio: a predictor of adult lung function

Directory of Open Access Journals (Sweden)

I-Nae Park

2014-02-01

Full Text Available Sex and sex hormones play a major role in lung physiology. It has been proposed that the ratio of the second to fourth digits (digit ratio is correlated with fetal sex hormones. We therefore hypothesized that digit ratio might help predict lung function. We investigated the relationship between digit ratio and pulmonary function test (PFT fi ndings. A total of 245 South Korean patients (162 male, 83 female aged from 34 to 90 years who were hospitalized for urological surgery were prospectively enrolled. Before administering the PFTs, the lengths of the second and fourth digits of the right hand were measured by a single investigator using a digital Vernier caliper. In males (n = 162, univariate and multivariate analysis using linear regression models showed that digit ratio was a signifi cant predictive factor of forced vital capacity (FVC and forced expiratory volume in 1 second (FEV1 (FVC: r = 0.156, P = 0.047; FEV1: r = 0.160, P = 0.042. In male ever-smokers (n = 69, lung functions (FVC and FEV1 were correlated with smoking exposure rather than digit ratio. In female never-smokers (n = 83, lung functions (FEV1 and FEV1/FVC ratio were positively correlated with digit ratio on univariate analysis (FEV1: r = 0.242, P = 0.027; FEV1/FVC ratio: r = 0.245, P = 0.026. Patients with lower digit ratios tend to have decreased lung function. These results suggest that digit ratio is a predictor of airway function.

Ratio Analysis: Where Investments Meet Mathematics.

Science.gov (United States)

Barton, Susan D.; Woodbury, Denise

2002-01-01

Discusses ratio analysis by which investments may be evaluated. Requires the use of fundamental mathematics, problem solving, and a comparison of the mathematical results within the framework of industry. (Author/NB)

Serum Thyroxine to Thyroxine-Binding Globulin Ratio in Pregnancy and Newborn

International Nuclear Information System (INIS)

Kim, Ji Yeul

1982-01-01

To evaluate the diagnostic value of the ratio of serum thyroxine(T 4 ) /thyroxine-binding globulin (TBG) for the thyroid status in pregnancy and newborn serum thyroxine, TBG, triiodothyronine, and free thyroxine levels were radioimmunoassayed in normal pregnant women at each of the trimesters, and the calculated serum T 4 /TBG ratios were compared with other parameters such as T 3 /TBG ratio and free T 4 /TBG ratio and free T 4 /TBG ratio. Serum T 4 levels were elevated with the proportionate increase in TBG levels during pregnancy, leading to the nearly constant value of serum T 4 /TBG ratios as in normal non-pregnant controls. In contrast, serum T 3 /TBG and free T 4 /TBG ratios varied considerably during pregnancy. In newborn, T 4 levels were nearly not changed with compared non-pregnant control value and TBG levels were elevated. The results indicate that serum T 4 /TBG ratio is a better parameter than others in evaluating the thyroid status during pregnancy and but newborn is a no better.

Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

NARCIS (Netherlands)

Moerdijk-Poortvliet, Tanja C. W.; Schierbeek, Henk; Houtekamer, Marco; van Engeland, Tom; Derrien, Delphine; Stal, Lucas J.; Boschker, Henricus T. S.

2015-01-01

We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ(13)C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

NARCIS (Netherlands)

Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

2015-01-01

We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of d13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

NARCIS (Netherlands)

Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

2015-01-01

Rationale: We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence,

Posterior distributions for likelihood ratios in forensic science.

Science.gov (United States)

van den Hout, Ardo; Alberink, Ivo

2016-09-01

Evaluation of evidence in forensic science is discussed using posterior distributions for likelihood ratios. Instead of eliminating the uncertainty by integrating (Bayes factor) or by conditioning on parameter values, uncertainty in the likelihood ratio is retained by parameter uncertainty derived from posterior distributions. A posterior distribution for a likelihood ratio can be summarised by the median and credible intervals. Using the posterior mean of the distribution is not recommended. An analysis of forensic data for body height estimation is undertaken. The posterior likelihood approach has been criticised both theoretically and with respect to applicability. This paper addresses the latter and illustrates an interesting application area. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

Urine Albumin and Albumin/ Creatinine Ratio

Science.gov (United States)

... it used? The urine albumin test or albumin/creatinine ratio (ACR) is used to screen people with chronic conditions, such as diabetes and high blood pressure ( hypertension ) that put them at an ...

Gyromagnetic ratio of charged Kerr-anti-de Sitter black holes

International Nuclear Information System (INIS)

Aliev, Alikram N

2007-01-01

We examine the gyromagnetic ratios of rotating and charged AdS black holes in four and higher spacetime dimensions. We compute the gyromagnetic ratio for Kerr-AdS black holes with an arbitrary electric charge in four dimensions and show that it corresponds to g = 2 irrespective of the AdS nature of the spacetime. We also compute the gyromagnetic ratio for Kerr-AdS black holes with a single angular momentum and with a test electric charge in all higher dimensions. The gyromagnetic ratio crucially depends on the dimensionless ratio of the rotation parameter to the curvature radius of the AdS background. At the critical limit, when the boundary Einstein universe is rotating at the speed of light, it exhibits a striking feature leading to g 2 regardless of the spacetime dimension. Next, we extend our consideration to include the exact metric for five-dimensional rotating charged black holes in minimal gauged supergravity. We show that the value of the gyromagnetic ratio found in the 'test-charge' approach remains unchanged for these black holes

Invited review: sex ratio and rheumatic disease.

Science.gov (United States)

Lockshin, M D

2001-11-01

Human illnesses affect men and women differently. In some cases (diseases of sex organs, diseases resulting from X or Y chromosome mutations), reasons for sex discrepancy are obvious, but in other cases no reason is apparent. Explanations for sex discrepancy of illness occur at different biological levels: molecular (e.g., imprinting, X-inactivation), cellular (sex-specific receptor activity), organ (endocrine influences), whole organism (size, age), and environmental-behavioral, including intrauterine influences. Autoimmunity represents a prototypical class of illness that has high female-to-male (F/M) ratios. Although the F/M ratios in autoimmune diseases are usually attributed to the influence of estrogenic hormones, evidence demonstrates that the attributed ratios are imprecise and that definitions and classifications of autoimmune diseases vary, rendering at least part of the counting imprecise. In addition, many studies on sex discrepancy of human disease fail to distinguish between disease incidence and disease severity. In April 2001, the Institute of Medicine of the National Academy of Sciences published Exploring the Biological Contributions to Human Health: Does Sex Matter? (Wizemann T and Pardue M-L, editors). This minireview summarizes the section of that report that concerns autoimmune and infectious disease. Some thyroid, rheumatic, and hepatic autoimmune diseases have high F/M ratios, whereas others have low. Those that have high ratios occur primarily in young adulthood. Gonadal hormones, if they play a role, likely do so through a threshold or permissive mechanism. Examples of sex differences that could be caused by environmental exposure, X inactivation, imprinting, X or Y chromosome genetic modulators, and intrauterine influences are presented as alternate, theoretical, and largely unexplored explanations for sex differences of incidence. The epidemiology of autoimmune diseases (young, female) suggests that an explanation for sex discrepancy of

Mother's occupation and sex ratio at birth

Directory of Open Access Journals (Sweden)

Amiot Volodymyr

2010-05-01

Full Text Available Abstract Background Many women are working outside of the home, occupying a multitude of jobs with varying degrees of responsibilities and levels of psychological stress. We investigated whether different job types in women are associated with child sex at birth, with the hypothesis that women in job types, which are categorized as "high psychological stress" jobs, would be more likely to give birth to a daughter than a son, as females are less vulnerable to unfavourable conditions during conception, pregnancy and after parturition, and are less costly to carry to term. Methods We investigated the effects of mother's age, maternal and paternal job type (and associated psychological stress levels and paternal income on sex ratio at birth. Our analyses were based on 16,384 incidences of birth from a six-year (2000 to 2005 inclusive childbirth dataset from Addenbrooke's Hospital in Cambridge, UK. We obtained a restricted data set from Addenbrooke's hospital with: maternal age, maternal and paternal occupations, and whether or not the child was first-born. Results Women in job types that were categorized as "high stress" were more likely to give birth to daughters, whereas women in job types that were categorized as "low stress" had equal sex ratios or a slight male bias in offspring. We also investigated whether maternal age, and her partner's income could be associated with reversed offspring sex ratio. We found no association between mother's age, her partner's job stress category or partner income on child sex. However, there was an important interaction between job stress category and partner income in some of the analyses. Partner income appears to attenuate the association between maternal job stress and sex ratios at moderate-income levels, and reverse it at high-income levels. Conclusions To our knowledge this is the first report on the association between women's job type stress categories and offspring sex ratio in humans, and the

Combined Effect of Contraction Ratio and Chamber Pressure on the Performance of a Gaseous Hydrogen-Liquid-Oxygen Combustor for a Given Propellant Weight Flow and Oxidant-Fuel Ratio

Science.gov (United States)

Hersch, Martin

1961-01-01

The effect of contraction ratio and chamber pressure on the combustion performance of a gaseous-hydrogen-liquid-oxygen combustor was investigated analytically and experimentally. The experiment was conducted with a "two-dimensional" gaseous-hydrogen-liquid-oxygen engine of about 150-pound thrust. The contraction ratio was varied from 1.5 to 6 by changing the nozzle throat area. This variation resulted in a chamber pressure variation of about 25 to 120 pounds per square inch. The experimental results were corrected for heat transfer to the engine walls and momentum pressure losses. The experimental performance, as evaluated in terms of characteristic exhaust velocity, was 98 percent of theoretical at contraction ratios greater than 3 but decreased very rapidly at smaller contraction ratios. The heat-transfer rate increased with increasing contraction ratio and chamber pressure; it was about 1 Btu per square inch per second at a contraction ratio of 1.5 and increased to about 3 at a contraction ratio of 6. The combined effects of contraction-ratio and chamber-pressure changes on performance were investigated analytically with a mixing model and a vaporization model. The mixing model predicted very poor mixing at contraction ratios below 3 and almost perfect mixing at higher contraction ratios. The performance predicted by the vaporization model was very close to 100 percent for all contraction ratios. From these results, it was concluded that the performance was limited by poor mixing at low contraction ratios and chamber pressures.

KERMA ratios in pediatric CT dosimetry

International Nuclear Information System (INIS)

Huda, Walter; Ogden, Kent M.; Lavallee, Robert L.; Roskopf, Marsha L.; Scalzetti, Ernest M.

2012-01-01

Patient organ doses may be estimated from CTDI values. More accurate estimates may be obtained by measuring KERMA (Kinetic Energy Released in Matter) in anthropomorphic phantoms and referencing these values to free-in-air X-ray intensity. To measure KERMA ratios (R K ) in pediatric phantoms at CT. CT scans produce an air KERMA K in a phantom and an air KERMA K CT at isocenter. KERMA ratios (R K ) are defined as (K/K CT ), measured using TLD chips in phantoms representing newborns to 10-year-olds. R K in the newborn is approximately constant. For the other phantoms, there is a peak R K value in the neck. The median R K values for the GE scanner at 120 kV were 0.92, 0.83, 0.77 and 0.76 for newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. Organ R K values were 0.91 ± 0.04, 0.84 ± 0.07, 0.74 ± 0.09 and 0.72 ± 0.10 in newborns, 1-year-olds, 5-year-olds and 10-year-olds, respectively. At 120 kV, a Siemens Sensation 16 scanner had R K values 5% higher than those of the GE LightSpeed Ultra. KERMA ratios may be combined with air KERMA measurements at the isocenter to estimate organ doses in pediatric CT patients. (orig.)

The Methane to Carbon Dioxide Ratio Produced during Peatland Decomposition and a Simple Approach for Distinguishing This Ratio

Science.gov (United States)

Chanton, J.; Hodgkins, S. B.; Cooper, W. T.; Glaser, P. H.; Corbett, J. E.; Crill, P. M.; Saleska, S. R.; Rich, V. I.; Holmes, B.; Hines, M. E.; Tfaily, M.; Kostka, J. E.

2014-12-01

Peatland organic matter is cellulose-like with an oxidation state of approximately zero. When this material decomposes by fermentation, stoichiometry dictates that CH4 and CO2 should be produced in a ratio approaching one. While this is generally the case in temperate zones, this production ratio is often departed from in boreal peatlands, where the ratio of belowground CH4/CO2 production varies between 0.1 and 1, indicating CO2 production by a mechanism in addition to fermentation. The in situ CO2/CH4 production ratio may be ascertained by analysis of the 13C isotopic composition of these products, because CO2 production unaccompanied by methane production produces CO2 with an isotopic composition similar to the parent organic matter while methanogenesis produces 13C depleted methane and 13C enriched CO2. The 13C enrichment in the subsurface CO2 pool is directly related to the amount of if formed from methane production and the isotopic composition of the methane itself. Excess CO2 production is associated with more acidic conditions, Sphagnum vegetation, high and low latitudes, methane production dominated by hydrogenotrophic methane production, 13C depleted methane, and generally, more nutrient depleted conditions. Three theories have been offered to explain these observations— 1) inhibition of acetate utilization, acetate build-up and diffusion to the surface and eventual aerobic oxidation, 2) the use of humic acids as electron acceptors, and the 3) utilization of organic oxygen to produce CO2. In support of #3, we find that 13C-NMR, Fourier transform infrared (FT IR) spectroscopy, and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) clearly show the evolution of polysaccharides and cellulose towards more decomposed humified alkyl compounds stripped of organic oxygen utilized to form CO2. Such decomposition results in more negative carbon oxidation states varying from -1 to -2. Coincident with this reduction in oxidation state, is the

Precise and accurate isotope ratio measurements by ICP-MS.

Science.gov (United States)

Becker, J S; Dietze, H J

2000-09-01

The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

Stopping-power ratios for dosimetry

International Nuclear Information System (INIS)

Andreo, P.

1988-01-01

The determination of the absorbed dose at a specified location in a medium irradiated with an electron or photon beam normally consists of two steps: (1) the determination of the mean absorbed dose to a detector by using a calibration factor or performing an absolute measurement, (2) the determination of the absorbed dose to the medium at the point of interest by calculations based on the knowledge of the absorbed dose to the detector and the different stopping and scattering properties of the medium and the detector material. When the influence of the detector is so small that the electron fluence in the medium is not modified, the ratio of the mass collision stopping power of the two materials accounts for the differences in energy deposition, and provides a conversion factor to relate the absorbed dose in both materials. Today, all national and international dosimetry protocols and codes of practice are based on such procedures, and the user easily can carry out these steps using tabulated data to convert a measured quantity to absorbed dose in the irradiated medium at the location of interest. Effects due to the spatial extension of the detector are taken into account using perturbation correction factors. The Monte Carlo method has become the most common and powerful calculational technique for determining the electron fluence (energy spectra) under different irradiation conditions. Cavity theory is then used to calculate stopping-power ratios. In this chapter, the different steps needed to evaluate s-ratios will be considered, emphasizing the different types of cavity-theory integrals and the Monte Carlo techniques used to derive the necessary electron spectra in the range of energies commonly used in radiation dosimetry, i.e., photon and electron beams with energies up to 50 MeV

Isotopic ratios in outbursting comet C/2015 ER61

Science.gov (United States)

Yang, Bin; Hutsemékers, Damien; Shinnaka, Yoshiharu; Opitom, Cyrielle; Manfroid, Jean; Jehin, Emmanuël; Meech, Karen J.; Hainaut, Olivier R.; Keane, Jacqueline V.; Gillon, Michaël

2018-02-01

Isotopic ratios in comets are critical to understanding the origin of cometary material and the physical and chemical conditions in the early solar nebula. Comet C/2015 ER61 (PANSTARRS) underwent an outburst with a total brightness increase of 2 magnitudes on the night of 2017 April 4. The sharp increase in brightness offered a rare opportunity to measure the isotopic ratios of the light elements in the coma of this comet. We obtained two high-resolution spectra of C/2015 ER61 with UVES/VLT on the nights of 2017 April 13 and 17. At the time of our observations, the comet was fading gradually following the outburst. We measured the nitrogen and carbon isotopic ratios from the CN violet (0, 0) band and found that 12C/13C = 100 ± 15, 14N/15N = 130 ± 15. In addition, we determined the 14N/15N ratio from four pairs of NH2 isotopolog lines and measured 14N/15N = 140 ± 28. The measured isotopic ratios of C/2015 ER61 do not deviate significantly from those of other comets.

Sex ratio and Wolbachia infection in the ant Formica exsecta.

Science.gov (United States)

Keller, L; Liautard, C; Reuter, M; Brown, W D; Sundström, L; Chapuisat, M

2001-08-01

Sex allocation data in social Hymenoptera provide some of the best tests of kin selection, parent-offspring conflict and sex ratio theories. However, these studies critically depend on controlling for confounding ecological factors and on identifying all parties that potentially manipulate colony sex ratio. It has been suggested that maternally inherited parasites may influence sex allocation in social Hymenoptera. If the parasites can influence sex allocation, infected colonies are predicted to invest more resources in females than non-infected colonies, because the parasites are transmitted through females but not males. Prime candidates for such sex ratio manipulation are Wolbachia, because these cytoplasmically transmitted bacteria have been shown to affect the sex ratio of host arthropods by cytoplasmic incompatibility, parthenogenesis, male-killing and feminization. In this study, we tested whether Wolbachia infection is associated with colony sex ratio in two populations of the ant Formica exsecta that have been the subject of extensive sex ratio studies. In these populations colonies specialize in the production of one sex or the other. We found that almost all F. exsecta colonies in both populations are infected with Wolbachia. However, in neither population did we find a significant association in the predicted direction between the prevalence of Wolbachia and colony sex ratio. In particular, colonies with a higher proportion of infected workers did not produce more females. Hence, we conclude that Wolbachia does not seem to alter the sex ratio of its hosts as a means to increase transmission rate in these two populations of ants.

Uncertainty importance analysis using parametric moment ratio functions.

Science.gov (United States)

Wei, Pengfei; Lu, Zhenzhou; Song, Jingwen

2014-02-01

This article presents a new importance analysis framework, called parametric moment ratio function, for measuring the reduction of model output uncertainty when the distribution parameters of inputs are changed, and the emphasis is put on the mean and variance ratio functions with respect to the variances of model inputs. The proposed concepts efficiently guide the analyst to achieve a targeted reduction on the model output mean and variance by operating on the variances of model inputs. The unbiased and progressive unbiased Monte Carlo estimators are also derived for the parametric mean and variance ratio functions, respectively. Only a set of samples is needed for implementing the proposed importance analysis by the proposed estimators, thus the computational cost is free of input dimensionality. An analytical test example with highly nonlinear behavior is introduced for illustrating the engineering significance of the proposed importance analysis technique and verifying the efficiency and convergence of the derived Monte Carlo estimators. Finally, the moment ratio function is applied to a planar 10-bar structure for achieving a targeted 50% reduction of the model output variance. © 2013 Society for Risk Analysis.

Poisson's Ratio and Auxetic Properties of Natural Rocks

Science.gov (United States)

Ji, Shaocheng; Li, Le; Motra, Hem Bahadur; Wuttke, Frank; Sun, Shengsi; Michibayashi, Katsuyoshi; Salisbury, Matthew H.

2018-02-01

Here we provide an appraisal of the Poisson's ratios (υ) for natural elements, common oxides, silicate minerals, and rocks with the purpose of searching for naturally auxetic materials. The Poisson's ratios of equivalently isotropic polycrystalline aggregates were calculated from dynamically measured elastic properties. Alpha-cristobalite is currently the only known naturally occurring mineral that has exclusively negative υ values at 20-1,500°C. Quartz and potentially berlinite (AlPO4) display auxetic behavior in the vicinity of their α-β structure transition. None of the crystalline igneous and metamorphic rocks (e.g., amphibolite, gabbro, granite, peridotite, and schist) display auxetic behavior at pressures of >5 MPa and room temperature. Our experimental measurements showed that quartz-rich sedimentary rocks (i.e., sandstone and siltstone) are most likely to be the only rocks with negative Poisson's ratios at low confining pressures (≤200 MPa) because their main constituent mineral, α-quartz, already has extremely low Poisson's ratio (υ = 0.08) and they contain microcracks, micropores, and secondary minerals. This finding may provide a new explanation for formation of dome-and-basin structures in quartz-rich sedimentary rocks in response to a horizontal compressional stress in the upper crust.

Avoiding mandatory hospital nurse staffing ratios: an economic commentary.

Science.gov (United States)

Buerhaus, Peter I

2009-01-01

The imposition of mandatory hospital nurse staffing ratios is among the more visible public policy initiatives affecting the nursing profession. Although the practice is intended to address problems in hospital nurse staffing and quality of patient care, this commentary argues that staffing ratios will lead to negative consequences for nurses involving the equity, efficiency, and costs of producing nursing care in hospitals. Rather than spend time and effort attempting to regulate nurse staffing, this commentary offers alternatives strategies that are directed at fixing the problems that motivate the advocates of staffing ratios.

Omniclassical Diffusion in Low Aspect Ratio Tokamaks

International Nuclear Information System (INIS)

Mynick, H.E.; White, R.B.; Gates, D.A.

2004-01-01

Recently reported numerical results for axisymmetric devices with low aspect ratio A found radial transport enhanced over the expected neoclassical value by a factor of 2 to 3. In this paper, we provide an explanation for this enhancement. Transport theory in toroidal devices usually assumes large A, and that the ratio B p /B t of the poloidal to the toroidal magnetic field is small. These assumptions result in transport which, in the low collision limit, is dominated by banana orbits, giving the largest collisionless excursion of a particle from an initial flux surface. However in a small aspect ratio device one may have B p /B t ∼ 1, and the gyroradius may be larger than the banana excursion. Here, we develop an approximate analytic transport theory valid for devices with arbitrary A. For low A, we find that the enhanced transport, referred to as omniclassical, is a combination of neoclassical and properly generalized classical effects, which become dominant in the low-A, B p /B t ∼ 1 regime. Good agreement of the analytic theory with numerical simulations is obtained

Optimized thick-wall cylinders by virtue of Poisson's ratio selection

International Nuclear Information System (INIS)

Whitty, J.P.M.; Henderson, B.; Francis, J.; Lloyd, N.

2011-01-01

The principal stress distributions in thick-wall cylinders due to variation in the Poisson's ratio are predicted using analytical and finite element methods. Analyses of appropriate brittle and ductile failure criteria show that under the isochoric pressure conditions investigated that auextic (i.e. those possessing a negative Poisson's ratio) materials act as stress concentrators; hence they are predicted to fail before their conventional (i.e. possessing a positive Poisson's ratio) material counterparts. The key finding of the work presented shows that for constrained thick-wall cylinders the maximum tensile principal stress can vanish at a particular Poisson's ratio and aspect ratio. This phenomenon is exploited in order to present an optimized design criterion for thick-wall cylinders. Moreover, via the use of a cogent finite element model, this criterion is also shown to be applicable for the design of micro-porous materials.

Predicting intrapartum fetal compromise using the fetal cerebro-umbilical ratio.

Science.gov (United States)

Sabdia, S; Greer, R M; Prior, T; Kumar, S

2015-05-01

The aim of this study was to explore the association between the cerebro-umbilical ratio measured at 35-37 weeks and intrapartum fetal compromise. This retrospective cross sectional study was conducted at the Mater Mothers' Hospital in Brisbane, Australia. Maternal demographics and fetal Doppler indices at 35-37 weeks gestation for 1381 women were correlated with intrapartum and neonatal outcomes. Babies born by caesarean section or instrumental delivery for fetal compromise had the lowest median cerebro-umbilical ratio 1.60 (IQR 1.22-2.08) compared to all other delivery groups (vaginal delivery, emergency delivery for failure to progress, emergency caesarean section for other reasons or elective caesarean section). The percentage of infants with a cerebro-umbilical ratio cerebro-umbilical ratio between the 10th-90th centile and 9.6% of infants with a cerebro-umbilical ratio > 90th centile required delivery for the same indication (p cerebro-umbilical ratio was associated with an increased risk of emergency delivery for fetal compromise, OR 2.03 (95% CI 1.41-2.92), p cerebro-umbilical ratio measured at 35-37 weeks is associated with a greater risk of intrapartum compromise. This is a relatively simple technique which could be used to risk stratify women in diverse healthcare settings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Alvar engine. An engine with variable compression ratio. Experiments and tests

Energy Technology Data Exchange (ETDEWEB)

Erlandsson, Olof

1998-09-01

This report is focused on tests with Variable Compression Ratio (VCR) engines, according to the Alvar engine principle. Variable compression ratio means an engine design where it is possible to change the nominal compression ratio. The purpose is to increase the fuel efficiency at part load by increasing the compression ratio. At maximum load, and maybe supercharging with for example turbocharger, it is not possible to keep a high compression ratio because of the knock phenomena. Knock is a shock wave caused by self-ignition of the fuel-air mix. If knock occurs, the engine will be exposed to a destructive load. Because of the reasons mentioned it would be an advantage if it would be possible to change the compression ratio continuously when the load changes. The Alvar engine provides a solution for variable compression ratio based on well-known engine components. This paper provides information about efficiency and emission characteristics from tests with two Alvar engines. Results from tests with a phase shift mechanism (for automatic compression ratio control) for the Alvar engine are also reviewed Examination paper. 5 refs, 23 figs, 2 tabs, 5 appendices

New Vehicle Detection Method with Aspect Ratio Estimation for Hypothesized Windows

Directory of Open Access Journals (Sweden)

Jisu Kim

2015-12-01

Full Text Available All kinds of vehicles have different ratios of width to height, which are called the aspect ratios. Most previous works, however, use a fixed aspect ratio for vehicle detection (VD. The use of a fixed vehicle aspect ratio for VD degrades the performance. Thus, the estimation of a vehicle aspect ratio is an important part of robust VD. Taking this idea into account, a new on-road vehicle detection system is proposed in this paper. The proposed method estimates the aspect ratio of the hypothesized windows to improve the VD performance. Our proposed method uses an Aggregate Channel Feature (ACF and a support vector machine (SVM to verify the hypothesized windows with the estimated aspect ratio. The contribution of this paper is threefold. First, the estimation of vehicle aspect ratio is inserted between the HG (hypothesis generation and the HV (hypothesis verification. Second, a simple HG method named a signed horizontal edge map is proposed to speed up VD. Third, a new measure is proposed to represent the overlapping ratio between the ground truth and the detection results. This new measure is used to show that the proposed method is better than previous works in terms of robust VD. Finally, the Pittsburgh dataset is used to verify the performance of the proposed method.

Ratios of involved nodes in early breast cancer

International Nuclear Information System (INIS)

Vinh-Hung, Vincent; Royce, Melanie; Verschraegen, Claire; Promish, Donald I; Cserni, Gábor; Van de Steene, Jan; Tai, Patricia; Vlastos, Georges; Voordeckers, Mia; Storme, Guy

2004-01-01

The number of lymph nodes found to be involved in an axillary dissection is among the most powerful prognostic factors in breast cancer, but it is confounded by the number of lymph nodes that have been examined. We investigate an idea that has surfaced recently in the literature (since 1999), namely that the proportion of node-positive lymph nodes (or a function thereof) is a much better predictor of survival than the number of excised and node-positive lymph nodes, alone or together. The data were abstracted from 83,686 cases registered in the Surveillance, Epidemiology, and End Results (SEER) program of women diagnosed with nonmetastatic T1–T2 primary breast carcinoma between 1988 and 1997, in whom axillary node dissection was performed. The end-point was death from breast cancer. Cox models based on different expressions of nodal involvement were compared using the Nagelkerke R 2 index (R 2 N ). Ratios were modeled as percentage and as log odds of involved nodes. Log odds were estimated in a way that avoids singularities (zero values) by using the empirical logistic transform. In node-negative cases both the number of nodes excised and the log odds were significant, with hazard ratios of 0.991 (95% confidence interval 0.986–0.997) and 1.150 (1.058–1.249), respectively, but without improving R 2 N . In node-positive cases the hazard ratios were 1.003–1.088 for the number of involved nodes, 0.966–1.005 for the number of excised nodes, 1.015–1.017 for the percentage, and 1.344–1.381 for the log odds. R 2 N improved from 0.067 (no nodal covariate) to 0.102 (models based on counts only) and to 0.108 (models based on ratios). Ratios are simple optimal predictors, in that they provide at least the same prognostic value as the more traditional staging based on counting of involved nodes, without replacing them with a needlessly complicated alternative. They can be viewed as a per patient standardization in which the number of involved nodes is standardized

Meiotic sex ratio variation in natural populations of Ceratodon purpureus (Ditrichaceae).

Science.gov (United States)

Norrell, Tatum E; Jones, Kelly S; Payton, Adam C; McDaniel, Stuart F

2014-09-01

• Sex ratio variation is a common but often unexplained phenomenon in species across the tree of life. Here we evaluate the hypothesis that meiotic sex ratio variation can contribute to the biased sex ratios found in natural populations of the moss Ceratodon purpureus.• We obtained sporophytes from several populations of C. purpureus from eastern North America. From each sporophyte, we estimated the mean spore viability by germinating replicate samples on agar plates. We estimated the meiotic sex ratio of each sporophyte by inferring the sex of a random sample of germinated spores (mean = 77) using a PCR-RFLP test. We tested for among-sporophyte variation in viability using an ANOVA and for deviations from 1:1 sex ratio using a χ(2)-test and evaluated the relationship between these quantities using a linear regression.• We found among-sporophyte variation in spore viability and meiotic sex ratio, suggesting that genetic variants that contribute to variation in both of these traits segregate within populations of this species. However, we found no relationship between these quantities, suggesting that factors other than sex ratio distorters contribute to variation in spore viability within populations.• These results demonstrate that sex ratio distortion may partially explain the population sex ratio variation seen in C. purpureus, but more generally that genetic conflict over meiotic segregation may contribute to fitness variation in this species. Overall, this study lays the groundwork for future studies on the genetic basis of meiotic sex ratio variation. © 2014 Botanical Society of America, Inc.

Optimization of solid content, carbon/nitrogen ratio and food/inoculum ratio for biogas production from food waste.

Science.gov (United States)

Dadaser-Celik, Filiz; Azgin, Sukru Taner; Yildiz, Yalcin Sevki

2016-12-01

Biogas production from food waste has been used as an efficient waste treatment option for years. The methane yields from decomposition of waste are, however, highly variable under different operating conditions. In this study, a statistical experimental design method (Taguchi OA 9 ) was implemented to investigate the effects of simultaneous variations of three parameters on methane production. The parameters investigated were solid content (SC), carbon/nitrogen ratio (C/N) and food/inoculum ratio (F/I). Two sets of experiments were conducted with nine anaerobic reactors operating under different conditions. Optimum conditions were determined using statistical analysis, such as analysis of variance (ANOVA). A confirmation experiment was carried out at optimum conditions to investigate the validity of the results. Statistical analysis showed that SC was the most important parameter for methane production with a 45% contribution, followed by F/I ratio with a 35% contribution. The optimum methane yield of 151 l kg -1 volatile solids (VS) was achieved after 24 days of digestion when SC was 4%, C/N was 28 and F/I were 0.3. The confirmation experiment provided a methane yield of 167 l kg -1 VS after 24 days. The analysis showed biogas production from food waste may be increased by optimization of operating conditions. © The Author(s) 2016.

Curious Sex Ratios and Cytoplasmic Genes

Indian Academy of Sciences (India)

instances of curious sex ratios exemplify an important principle: the fitness ..... markable transition - the whole means of sex determination has changed. No longer ... to the cytoplasmic symbiont is self-evident; the symbionts simply increase the.

Predictive value of C-reactive protein/albumin ratio in acute pancreatitis.

Science.gov (United States)

Kaplan, Mustafa; Ates, Ihsan; Akpinar, Muhammed Yener; Yuksel, Mahmut; Kuzu, Ufuk Baris; Kacar, Sabite; Coskun, Orhan; Kayacetin, Ertugrul

2017-08-15

Serum C-reactive protein (CRP) increases and albumin decreases in patients with inflammation and infection. However, their role in patients with acute pancreatitis is not clear. The present study was to investigate the predictive significance of the CRP/albumin ratio for the prognosis and mortality in acute pancreatitis patients. This study was performed retrospectively with 192 acute pancreatitis patients between January 2002 and June 2015. Ranson scores, Atlanta classification and CRP/albumin ratios of the patients were calculated. The CRP/albumin ratio was higher in deceased patients compared to survivors. The CRP/albumin ratio was positively correlated with Ranson score and Atlanta classification in particular and with important prognostic markers such as hospitalization time, CRP and erythrocyte sedimentation rate. In addition to the CRP/albumin ratio, necrotizing pancreatitis type, moderately severe and severe Atlanta classification, and total Ranson score were independent risk factors of mortality. It was found that an increase of 1 unit in the CRP/albumin ratio resulted in an increase of 1.52 times in mortality risk. A prediction value about CRP/albumin ratio >16.28 was found to be a significant marker in predicting mortality with 92.1% sensitivity and 58.0% specificity. It was seen that Ranson and Atlanta classification were higher in patients with CRP/albumin ratio >16.28 compared with those with CRP/albumin ratio ≤16.28. Patients with CRP/albumin ratio >16.28 had a 19.3 times higher chance of death. The CRP/albumin ratio is a novel but promising, easy-to-measure, repeatable, non-invasive inflammation-based prognostic score in acute pancreatitis. Copyright © 2017 The Editorial Board of Hepatobiliary & Pancreatic Diseases International. Published by Elsevier B.V. All rights reserved.

Sacroiliac Joint/Sacrum Uptake Ratio Measured by Quantitative Sacroiliac Joint Scintigraphy

International Nuclear Information System (INIS)

Lee, Young Yiul; Park, Seon Yang; Lee, Myung Chul; Choi, Sang Jae; Cho, Bo Youn; Choe, Kang Won; Koh, Chang Soon

1982-01-01

To evaluate the diagnostic usefulness and significance of quantitative sacroiliac joint scintigraphy in the assessment of sacroiliitis, we measured Sacroiliac Joint/Sacrum Uptake Ratio (SIS Ratio) by region of interest (ROI) method using 99m Tc-methylene diphosphonate. The observed results were as follows:1) Using ROI method, the SIS ratios for the control group of 65 persons were 1.05±0.08 (left) and 1.06±0.07 (right) which were narrower in range than those of slice method (mean±S.D.) 2) The effects of age, gender and laterality on SIS ratio were not significant. 3) In left side, one of 6 patients with rheumatoid arthritis had SIS ratio in excess of 2 standard deviation of normal control group, and remainder had SIS ratios within normal limit. In right side, 3 patients had SIS ratios in excess of 2 standard deviation of normal control group, and remainder, within normal limit. 4) In both sacroiliac joint, 2 of 3 patients having sacroiliitis clinically with Reiter's syndrome whose pelvis A-P X-ray findings showed normal had high SIS ratios (left/right; 1.31/1.69, 1.90/1.80), but SIS ratio of one patient who bad no evidence of sacroiliitis clinically was within normal limit. 5) In 6 patients with ankylosing spondylitis in both sacroiliac joints, q whose pelvis A-P X-ray findings showed severe sclerotic change of sacroiliac pints had SIS ratio within normal limit or below that of normal control group, and SIS ratios of 2 patients whose pelvis A-P X-ray findings showed were increased. 6) 4 of 5 patients with low back pain of which cause could not be evaluated clinically and radiologically had SIS ratios in excess of that of normal control group. It would be concluded the quantitative sacroiliac joint scintigraphy is useful and sensitive screening method in the diagnosis as well as in the assessment clinical activity of sacroiliitis.

The evolution of sex ratios and sex-determining systems

NARCIS (Netherlands)

Uller, Tobias; Pen, Ido; Wapstra, Erik; Beukeboom, Leo W.; Komdeur, Jan

Sex determination is a fundamental process governed by diverse mechanisms. Sex ratio selection is commonly implicated in the evolution of sex-determining systems, although formal models are rare. Here, we argue that, although sex ratio selection can induce shifts in sex determination, genomic

Distribution of Bowen ratio over the north Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Rao, G.R.L.; Rao, M.V.; Prasad, P.H.; Reddy, K.G.

The monthly averages of Bowen ratio over the north Indian Ocean have been computed Three typical situations in the months of January May and September are taken for the present study Month to month differences in the Bowen ratio over the study...

Parental correlates of offspring sex ratio in Eurasian Oystercatchers

NARCIS (Netherlands)

Heg, D.; Dingemanse, NJ; Lessells, CM; Mateman, AC

2000-01-01

We investigated hatchling and fledgling sex ratios in Eurasian Oystercatchers (Haematopus ostralegus) using random amplified polymorphic DNA markers. The overall hatchling (53% males, n = 374 hatchlings from 177 broods) and fledgling (49% males, n = 51) sex ratio did not differ significantly from

Dynamic Responses of Flexible Cylinders with Low Mass Ratio

Science.gov (United States)

Olaoye, Abiodun; Wang, Zhicheng; Triantafyllou, Michael

2017-11-01

Flexible cylinders with low mass ratios such as composite risers are attractive in the offshore industry because they require lower top tension and are less likely to buckle under self-weight compared to steel risers. However, their relatively low stiffness characteristics make them more vulnerable to vortex induced vibrations. Additionally, numerical investigation of the dynamic responses of such structures based on realistic conditions is limited by high Reynolds number, complex sheared flow profile, large aspect ratio and low mass ratio challenges. In the framework of Fourier spectral/hp element method, the current technique employs entropy-viscosity method (EVM) based large-eddy simulation approach for flow solver and fictitious added mass method for structure solver. The combination of both methods can handle fluid-structure interaction problems at high Reynolds number with low mass ratio. A validation of the numerical approach is provided by comparison with experiments.

Current switching ratio optimization using dual pocket doping engineering

Science.gov (United States)

Dash, Sidhartha; Sahoo, Girija Shankar; Mishra, Guru Prasad

2018-01-01

This paper presents a smart idea to maximize current switching ratio of cylindrical gate tunnel FET (CGT) by growing pocket layers in both source and channel region. The pocket layers positioned in the source and channel of the device provides significant improvement in ON-state and OFF-state current respectively. The dual pocket doped cylindrical gate TFET (DP-CGT) exhibits much superior performance in term of drain current, transconductance and current ratio as compared to conventional CGT, channel pocket doped CGT (CP-CGT) and source pocket doped CGT (SP-CGT). Further, the current ratio has been optimized w.r.t. width and instantaneous position both the pocket layers. The much improved current ratio and low power consumption makes the proposed device suitable for low-power and high speed application. The simulation work of DP-CGT is done using 3D Sentaurus TCAD device simulator from Synopsys.

Metabolic Risk Susceptibility in Men Is Partially Related to Adiponectin/Leptin Ratio

Directory of Open Access Journals (Sweden)

Gloria Lena Vega

2013-01-01

Full Text Available Background. High adiponectin/leptin ratio may be protective from metabolic risks imparted by high triglyceride, low HDL, and insulin resistance. Methods. This cross-sectional study examines plasma adipokine levels in 428 adult men who were subgrouped according to low (<6.5 μg/mLand high (≥6.5 μg/mLadiponectin levels or a low or high ratio of adiponectin/leptin. Results. Men with high adiponectin/leptin ratio had lower plasma triglyceride and higher HDL cholesterol than those with low ratio. Similarly, those with high adiponectin/leptin ratio had lower TG/HDL cholesterol ratio and HOMA2-IR than those with low ratio. In contrast, levels of adiponectin or the ratio of adiponectin/leptin did not associate with systolic blood pressure. But the ratio of adiponectin/leptin decreased progressively with the increase in the number of risk factors for metabolic syndrome. Conclusion. Adipokine levels may reflect adipose tissue triglyceride storage capacity and insulin sensitivity. Leptin is an index of fat mass, and adiponectin is a biomarker of triglyceride metabolism and insulin sensitivity. Men with high adiponectin/leptin ratios have better triglyceride profile and insulin sensitivity than men with a low ratio regardless of waist girth.

Regional sensitivity analysis using revised mean and variance ratio functions

International Nuclear Information System (INIS)

Wei, Pengfei; Lu, Zhenzhou; Ruan, Wenbin; Song, Jingwen

2014-01-01

The variance ratio function, derived from the contribution to sample variance (CSV) plot, is a regional sensitivity index for studying how much the output deviates from the original mean of model output when the distribution range of one input is reduced and to measure the contribution of different distribution ranges of each input to the variance of model output. In this paper, the revised mean and variance ratio functions are developed for quantifying the actual change of the model output mean and variance, respectively, when one reduces the range of one input. The connection between the revised variance ratio function and the original one is derived and discussed. It is shown that compared with the classical variance ratio function, the revised one is more suitable to the evaluation of model output variance due to reduced ranges of model inputs. A Monte Carlo procedure, which needs only a set of samples for implementing it, is developed for efficiently computing the revised mean and variance ratio functions. The revised mean and variance ratio functions are compared with the classical ones by using the Ishigami function. At last, they are applied to a planar 10-bar structure

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

International Nuclear Information System (INIS)

Hudak, P.F.

2003-01-01

Results have important implications for identifying animal sources of contaminated groundwater. - 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, quarter-horse, 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

Achieving high aspect ratio wrinkles by modifying material network stress.

Science.gov (United States)

Chen, Yu-Cheng; Wang, Yan; McCarthy, Thomas J; Crosby, Alfred J

2017-06-07

Wrinkle aspect ratio, or the amplitude divided by the wavelength, is hindered by strain localization transitions when an increasing global compressive stress is applied to synthetic material systems. However, many examples from living organisms show extremely high aspect ratios, such as gut villi and flower petals. We use three experimental approaches to demonstrate that these high aspect ratio structures can be achieved by modifying the network stress in the wrinkle substrate. We modify the wrinkle stress and effectively delay the strain localization transition, such as folding, to larger aspect ratios by using a zero-stress initial wavy substrate, creating a secondary network with post-curing, or using chemical stress relaxation materials. A wrinkle aspect ratio as high as 0.85, almost three times higher than common values of synthetic wrinkles, is achieved, and a quantitative framework is presented to provide understanding the different strategies and predictions for future investigations.

Elliptic nozzle aspect ratio effect on controlled jet propagation

Energy Technology Data Exchange (ETDEWEB)

Kumar, S M Aravindh; Rathakrishnan, Ethirajan, E-mail: aravinds@iitk.ac.in, E-mail: erath@iitk.ac.in [Department of Aerospace Engineering, Indian Institute of Technology, Kanpur (India)

2017-04-15

The present study deals with the control of a Mach 2 elliptic jet from a convergent–divergent elliptic nozzle of aspect ratio 4 using tabs at the nozzle exit. The experiments were carried out for rectangular and triangular tabs of the same blockage, placed along the major and minor axes of the nozzle exit, at different levels of nozzle expansion. The triangular tabs along the minor axis promoted superior mixing compared to the other controlled jets and caused substantial core length reduction at all the nozzle pressure ratios studied. The rectangular tabs along the minor axis caused core length reduction at all pressure ratios, but the values were minimal compared to that of triangular tabs along the minor axis. For all the test conditions, the mixing promotion caused by tabs along the major axis was inferior to that of tabs along the minor axis. The waves present in the core of controlled jets were visualized using a shadowgraph. Comparison of the present results with the results of a controlled Mach 2 elliptic jet of aspect ratio 2 (Aravindh Kumar and Sathakrishnan 2016 J. Propulsion Power 32 121–33, Aravindh Kumar and Rathakrishnan 2016 J. Aerospace Eng. at press (doi:10.1177/0954410016652921)) show that for all levels of expansion, the mixing effectiveness of triangular tabs along the minor axis of an aspect ratio 4 nozzle is better than rectangular or triangular tabs along the minor axis of an aspect ratio 2 nozzle. (paper)

Elliptic nozzle aspect ratio effect on controlled jet propagation

International Nuclear Information System (INIS)

Kumar, S M Aravindh; Rathakrishnan, Ethirajan

2017-01-01

The present study deals with the control of a Mach 2 elliptic jet from a convergent–divergent elliptic nozzle of aspect ratio 4 using tabs at the nozzle exit. The experiments were carried out for rectangular and triangular tabs of the same blockage, placed along the major and minor axes of the nozzle exit, at different levels of nozzle expansion. The triangular tabs along the minor axis promoted superior mixing compared to the other controlled jets and caused substantial core length reduction at all the nozzle pressure ratios studied. The rectangular tabs along the minor axis caused core length reduction at all pressure ratios, but the values were minimal compared to that of triangular tabs along the minor axis. For all the test conditions, the mixing promotion caused by tabs along the major axis was inferior to that of tabs along the minor axis. The waves present in the core of controlled jets were visualized using a shadowgraph. Comparison of the present results with the results of a controlled Mach 2 elliptic jet of aspect ratio 2 (Aravindh Kumar and Sathakrishnan 2016 J. Propulsion Power 32 121–33, Aravindh Kumar and Rathakrishnan 2016 J. Aerospace Eng. at press (doi:10.1177/0954410016652921)) show that for all levels of expansion, the mixing effectiveness of triangular tabs along the minor axis of an aspect ratio 4 nozzle is better than rectangular or triangular tabs along the minor axis of an aspect ratio 2 nozzle. (paper)

Performance evaluation using bootstrapping DEA techniques: Evidence from industry ratio analysis

OpenAIRE

Halkos, George; Tzeremes, Nickolaos

2010-01-01

In Data Envelopment Analysis (DEA) context financial data/ ratios have been used in order to produce a unified measure of performance metric. However, several scholars have indicated that the inclusion of financial ratios create biased efficiency estimates with implications on firms’ and industries’ performance evaluation. There have been several DEA formulations and techniques dealing with this problem including sensitivity analysis, Prior-Ratio-Analysis and DEA/ output–input ratio analysis ...

Introducing errors in progress ratios determined from experience curves

NARCIS (Netherlands)

van Sark, W.G.J.H.M.

2008-01-01

Progress ratios (PRs) derived from historical data in experience curves are used for forecasting development of many technologies as a means to model endogenous technical change in for instance climate–economy models. These forecasts are highly sensitive to uncertainties in the progress ratio. As a

Diagnosis of childhood hypertension: is blood pressure height ratio ...

African Journals Online (AJOL)

Blood pressure was also recorded according to the standard method. Systolic and diastolic blood pressure to height ratio were then calculated. Receiver operating curves was used to assess the ability of systolic blood and diastolic blood pressure height ratio to discriminate childhood prehypertension and hypertension.

Sex Dimorphism of the Heart Diameters and Cardiothoracic Ratios ...

African Journals Online (AJOL)

Objective: To determine gender associated differences in the cardiothoracic ratio (CTR) and heart diameters in a normal Nigerian population. Subject and Method: The normal heart diameters and cardiothoracic ratios were measured from posteroanterior (PA) chest radiographs of healthy 510 male and 508 female ...

K0/K+ ratio in relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Ivanov, Yu.B.; Russkikh, V.N.

1996-11-01

It is shown that ratio of production yields of K 0 and K + mesons in collisions of isotopically asymmetric nuclei at incident energies ∼ 1 GeV/nucleon is related directly enough to temperature of nuclear matter at the initial stage of the collision. Sensitivity of the K 0 /K + ratio to the temperature variation is analyzed. Ambiguities, associated with interpretation of this quantity as a probe of nuclear temperature, are discussed. It is argued that the K 0 /K + ratio is a fairly model-independent quantity, provided channels with Δ isobars dominate the kaon production. (orig.)

Ratio of νe/νμ in atmospheric neutrinos

International Nuclear Information System (INIS)

Barr, S.; Gaisser, T.K.; Tilav, S.

1988-01-01

When the effect of muon polarization is included, the calculated ratio ν e /ν μ for atmospheric neutrinos with energies above ≅ 200 MeV is increased by 10-20% compared to the result when polarization is neglected. We give an analytic derivation of this ratio for the artificial case of a power law differential spectrum of parent pions propagating in an atmosphere in which all pions and muons decay. This is sufficient to estimate the effect on the calculated ratio of electron-like to muon-like events induced by neutrino interactions in large underground detectors. (orig.)

Isotope ratio monitoring LC/MS (IRM-LC/MS): new applications

International Nuclear Information System (INIS)

Juchelka, D; Hilkert, A.; Krummen, M.

2005-01-01

With the introduction of compound specific isotope analysis by isotope ratio monitoring GC/ MS (IRM-GC/MS) the immediate demand for similar applications using HPLC was created. Many compounds of biological, medical, pharmaceutical and environmental interest are not volatile or too polar. Consequently, they cannot be directly analyzed by gas chromatography. In IRM-GC/MS the carrier is helium, which does not interfere with the essential combust ion step prior to isotope ratio mass spectrometry (IRMS). In opposite the LC mobile phase has inhibited a similar direct conversion up to now. All earlier IRM-LC/MS approaches were based on the removal of the liquid phase prior to combustion risking fractionation of the isotope ratios of the eluted compounds. To avoid such restrictions we developed a new continuous flow concept for the coupling of an HPLC system to the isotope ratio MS for 13 C/ 12C isotope ratio analysis. In the Finnigan LC IsoLink, the liquid phase is not removed from the sample prior to oxidation. The sample is oxidized still in the mobile phase followed by on-line separation of the CO 2 from the liquid phase and transfer into the isotope ratio MS. Therefore, this strategy is based on water and inorganic buffers as mobile phase. The new approach opens up a whole new world in the application of gas isotope ratio mass spectrometry. The 13 C/ 12 C ratio s of organic acids, amino acids, carbohydrates and nucleotides can now be measured. These components typically within a complex matrix are separated by liquid chromatography followed by on-line determination of the isotope ratios. The draw backs of using derivatization and off-line preparation procedures can now be over come. This new technique allow s studying biochemical cycles, running tracer experiments and determining the origin of components. Applications from different scientific areas such as biogeochemistry, molecular biology, and pharmacy as well as authenticity control o f foods will be presented

Relationship between Serum Lipoprotein Ratios and Insulin Resistance in Polycystic Ovary Syndrome

Directory of Open Access Journals (Sweden)

Shou-Kui Xiang

2012-01-01

Full Text Available Objective. To investigate the association between serum lipoprotein ratios and insulin resistance in women with polycystic ovarian syndrome (PCOS. Methods. 105 PCOS patients and 109 controls were randomly enrolled in the study. Serum levels of luteinizing hormone (LH, follicle-stimulating hormone (FSH, estradiol (E2, total testosterone (T, fasting glucose (FBG, fasting insulin (FINS, serum triglycerides (TG, total cholesterol (TC, high-density lipoprotein (HDL-C, and low-density lipoprotein (LDL-C levels were checked, and then TG/HDL-C ratio, TC/HDL-C, ratio and LDL-C/HDL-C ratio were calculated. The homeostasis model assessment of insulin resistance (HOMA-IR was used to calculate the insulin resistance. Results. All lipoprotein ratios were significantly higher in PCOS patients as compared to healthy controls (<0.05. TG/HDL-C ratio, TC/HDL-C ratio, and LDL-C/HDL-C ratio were significantly correlated with HOMA-IR (<0.05. The ROC curve demonstrated that TC/HDL-C ratio had higher sensitivity and specificity in diagnosing PCOS with insulin resistance. Conclusion. This study demonstrates that serum lipoprotein ratio significantly correlates with insulin resistance and can be used as the marker of insulin resistance in PCOS patients.

An Improved Optimal Slip Ratio Prediction considering Tyre Inflation Pressure Changes

Directory of Open Access Journals (Sweden)

Guoxing Li

2015-01-01

Full Text Available The prediction of optimal slip ratio is crucial to vehicle control systems. Many studies have verified there is a definitive impact of tyre pressure change on the optimal slip ratio. However, the existing method of optimal slip ratio prediction has not taken into account the influence of tyre pressure changes. By introducing a second-order factor, an improved optimal slip ratio prediction considering tyre inflation pressure is proposed in this paper. In order to verify and evaluate the performance of the improved prediction, a cosimulation platform is developed by using MATLAB/Simulink and CarSim software packages, achieving a comprehensive simulation study of vehicle braking performance cooperated with an ABS controller. The simulation results show that the braking distances and braking time under different tyre pressures and initial braking speeds are effectively shortened with the improved prediction of optimal slip ratio. When the tyre pressure is slightly lower than the nominal pressure, the difference of braking performances between original optimal slip ratio and improved optimal slip ratio is the most obvious.

Periodic equivalence ratio modulation method and apparatus for controlling combustion instability

Science.gov (United States)

Richards, George A.; Janus, Michael C.; Griffith, Richard A.

2000-01-01

The periodic equivalence ratio modulation (PERM) method and apparatus significantly reduces and/or eliminates unstable conditions within a combustion chamber. The method involves modulating the equivalence ratio for the combustion device, such that the combustion device periodically operates outside of an identified unstable oscillation region. The equivalence ratio is modulated between preselected reference points, according to the shape of the oscillation region and operating parameters of the system. Preferably, the equivalence ratio is modulated from a first stable condition to a second stable condition, and, alternatively, the equivalence ratio is modulated from a stable condition to an unstable condition. The method is further applicable to multi-nozzle combustor designs, whereby individual nozzles are alternately modulated from stable to unstable conditions. Periodic equivalence ratio modulation (PERM) is accomplished by active control involving periodic, low frequency fuel modulation, whereby low frequency fuel pulses are injected into the main fuel delivery. Importantly, the fuel pulses are injected at a rate so as not to affect the desired time-average equivalence ratio for the combustion device.

Measurement of the inclusive charmless and double-charm B branching ratios

CERN Document Server

Abreu, P; Adye, T; Adzic, P; Alekseev, G D; Alemany, R; Allport, P P; Almehed, S; Amaldi, Ugo; Amato, S; Andersson, P; Andreazza, A; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bärring, O; Bates, M J; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Belous, K S; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bizouard, M A; Bloch, D; Bonesini, M; Bonivento, W; Boonekamp, M; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozovic, I; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Brown, R; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Cerruti, C; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chen, M; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Collins, P; Colomer, M; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; D'Almagne, B; Damgaard, G; Dauncey, P D; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Di Diodato, A; Djannati, A; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Duperrin, A; Durand, J D; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Ellert, M; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Fayot, J; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Fichet, S; Firestone, A; Fischer, P A; Flagmeyer, U; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gaspar, M; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gerdyukov, L N; Ghodbane, N; Glege, F; Gokieli, R; Golob, B; González-Caballero, I; Gopal, Gian P; Gorn, L; Górski, M; Gracco, Valerio; Grahl, J; Graziani, E; Green, C; Grefrath, A; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Haider, S; Hajduk, Z; Hallgren, A; Hamacher, K; Harris, F J; Hedberg, V; Heising, S; Henriques, R P; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Holthuizen, D J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, C; Juillot, P; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Khokhlov, Yu A; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Knoblauch, D; Kokkinias, P; Koratzinos, M; Korcyl, K; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kreuter, C; Kronkvist, I J; Krumshtein, Z; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leisos, A; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Lethuillier, M; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Mahon, J R; Maio, A; Malek, A; Malmgren, T G M; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, F; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Medbo, J; Meroni, C; Meyer, W T; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Moreau, X; Morettini, P; Münich, K; Mulders, M; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Némécek, S; Neufeld, N; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Nikolenko, M; Niss, P; Nomerotski, A; Normand, Ainsley; Nygren, A; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Paiano, S; Pain, R; Paiva, R; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Piana, G; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Rames, J; Ratoff, P N; Read, A L; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ruiz, A; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sampsonidis, D; Sannino, M; Schneider, H; Schwickerath, U; Schyns, M A E; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Sekulin, R L; Shellard, R C; Sheridan, A; Silvestre, R; Simonetto, F; Sissakian, A N; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Solovyanov, O; Sopczak, André; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stampfer, D; Stanescu, C; Stanic, S; Stapnes, Steinar; Stavitski, I; Stevenson, K; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Chikilev, O G; Tegenfeldt, F; Terranova, F; Thomas, J; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Todorova, S; Toet, D Z; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Vulpen, I B; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Verzi, V; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Waldner, F; Weiser, C; Wetherell, Alan M; Wicke, D; Wickens, J H; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Wlodek, T; Wolf, G; Yi, J; Yushchenko, O P; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

1998-01-01

The DELPHI experiment at LEP has measured the inclusive charmless $B$ hadron decay branching ratio, the $B$ branching ratio into two charmed particles, and the total number of charmed particles per $B$ decay, using the hadronic Z data taken between 1992 and 1995. The results are extracted from a fit to the $b$-tagging probability distribution based on the precise impact parameter measurements made using the microvertex detector. The inclusive charmless $B$ branching ratio, including $B$ decays into hidden charm ($c\\bar{c}$), is measured to be $0.033 \\pm 0.021$. The $B$ branching ratio into two open charmed particles is $0.136 \\pm 0.042$. The mean number of charmed particles per $B$ decay (including hidden charm) is $1.147 \\pm 0.041$. After subtracting the $B$ decay branching ratio into hidden charm, the charmless $B$ branching ratio is found to be $0.007 \\pm 0.021$, compatible with the Standard Model expectation. Models that predict an additional contribution to the charmless $B$ branching ratio of 0.037 or h...

Intrinsic ratios of glucose, fructose, glycerol and ethanol 13C/12C isotopic ratio determined by HPLC-co-IRMS: toward determining constants for wine authentication.

Science.gov (United States)

Guyon, François; Gaillard, Laetitia; Salagoïty, Marie-Hélène; Médina, Bernard

2011-09-01

High-performance liquid chromatography linked to isotope ratio mass spectrometry (HPLC-co-IRMS) via a Liquiface© interface has been used to simultaneously determine (13)C isotope ratios of glucose (G), fructose (F), glycerol (Gly) and ethanol (Eth) in sweet and semi-sweet wines. The data has been used the study of wine authenticity. For this purpose, 20 authentic wines from various French production areas and various vintages have been analyzed after dilution in pure water from 20 to 200 times according to sugar content. If the (13)C isotope ratios vary according to the production area and the vintage, it appears that internal ratios of (13)C isotope ratios (R((13)C)) of the four compounds studied can be considered as a constant. Thus, ratios of isotope ratios are found to be 1.00 ± 0.04 and 1.02 ± 0.08 for R((13)C(G/F)) and R((13)C(Gly/Eth)), respectively. Moreover, R((13)C(Eth/Sugar)) is found to be 1.15 ± 0.10 and 1.16 ± 0.08 for R((13)C(Gly/Sugar)). Additions of glucose, fructose and glycerol to a reference wine show a variation of the R((13)C) value for a single product addition as low as 2.5 g/L(-1). Eighteen commercial wines and 17 concentrated musts have been analyzed. Three wine samples are suspicious as the R((13)C) values are out of range indicating a sweetening treatment. Moreover, concentrated must analysis shows that (13)C isotope ratio can be also used directly to determine the authenticity of the matrix.

Determining sex ratios of turtle hatchlings

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Previous status assessments of marine turtles have assumed that the natural sex ratio of a marine turtle population is 1:1 (e.g. Conant et al. 2009). However, this...

Earnings quality and P/E ratio: Evidence from Tehran Stock Exchange

Directory of Open Access Journals (Sweden)

Hassan Ghodrati

2014-08-01

Full Text Available This paper evaluates the impacts of earnings quality criteria on the ratio of price to earnings per share (P/E on 88 accepted companies in Tehran Stock Exchange (TSE over the period 2007- 2012. The results indicate that there was a positive and significant relationship between the P/E ratio and cash dividend. There is also a positive and significant relationship between P/E ratio as dependent variable and the gross profit ratio to sales. On the other hand, there is a significant reverse relationship between P/E ratio and the profit variability. However, no significant relationship exists between P/E as dependent variable and deferrals (accruals variable.

Calcium isotope ratios in animal and human bone

Science.gov (United States)

Reynard, L. M.; Henderson, G. M.; Hedges, R. E. M.

2010-07-01

Calcium isotopes in tissues are thought to be influenced by an individual's diet, reflecting parameters such as trophic level and dairy consumption, but this has not been carefully assessed. We report the calcium isotope ratios (δ 44/42Ca) of modern and archaeological animal and human bone ( n = 216). Modern sheep raised at the same location show 0.14 ± 0.08‰ higher δ 44/42Ca in females than in males, which we attribute to lactation by the ewes. In the archaeological bone samples the calcium isotope ratios of the herbivorous fauna vary by location. At a single site, the archaeological fauna do not show a trophic level effect. Humans have lower δ 44/42Ca than the mean site fauna by 0.22 ± 0.22‰, and the humans have a greater δ 44/42Ca range than the animals. No effect of sex or age on the calcium isotope ratios was found, and intra-individual skeletal δ 44/42Ca variability is negligible. We rule out dairy consumption as the main cause of the lower human δ 44/42Ca, based on results from sites pre-dating animal domestication and dairy availability, and suggest instead that individual physiology and calcium intake may be important in determining bone calcium isotope ratios.

Stress ratio determination from the core-disking phenomenon

International Nuclear Information System (INIS)

Lehnhoff, T.F.; Stefansson, B.; Thirumalai, K.

1982-08-01

The ability to predict in situ stress conditions from standard core samples offers planning and site-selection advantages for most underground facilities. This paper presents an empirical relation for estimating the horizontal to vertical stress ratio in basalt. The resulting estimates can then be used to help assess the extent to which measurement of in situ stress is required. The core disking phenomenon has long been used as an indicator of high in situ stress. It is concluded that disks form as the result of tensile failure initiation rather than shear failure initiation of the core. It is deduced that the tensile failure begins at the edge of the core and propagates toward the center in shear rather than beginning at the center and propagating outward. An empirical relation for horizontal to vertical stress ratio variation with depth has been developed and is shown to agree substantially with previous measured horizontal to vertical stress ratios for locations in several areas of the world. The stress-ratio predictions are justified based on finite-element studies using linear elastic analysis and also nonlinear (tension cut-off) analysis. Indications of fracture propagation paths were determined from the analyses. The shape of the predicted propagation path agrees well with physical observations

THE CONFLUENCE RATIO OF THE TRANSYLVANIAN BASIN RIVERS

Directory of Open Access Journals (Sweden)

ROŞIAN GH.

2014-03-01

Full Text Available There are many possibilities to assess the hydrological and geomorphological evolution of a territory. Among them, one remarks the confluence ratio of the rivers belonging to different catchment areas. The values of this indicator may provide information regarding the stage of evolution of the fluvial landforms in the Transylvanian Basin. Also, the values may serve for the calculation of other parameters of catchment areas like: the degree of finishing of the drainage basin for its corresponding order, the density of river segments within a catchment area etc. To calculate the confluence ratio, 35 catchment areas of different orders have been selected. The confluence ratio varies between 3.04 and 6.07. The large range of values demonstrates the existence of a heterogeneous lithology and of morphological and hydrographical contrasts from one catchment area to the other. The existence of values above 5, correlated also with observations in the field, reveals an accelerated dynamics of the geomorphological processes in those catchment areas. This dynamic is mainly supported by the high landform fragmentation due to the first order rivers. In contrast, the catchment areas that have a confluence ratio below 5 are in a more advanced stage of evolution with stable slopes, unable to initiate new first order river segments.

The four-loop six-gluon NMHV ratio function

Energy Technology Data Exchange (ETDEWEB)

Dixon, Lance J. [SLAC National Accelerator Lab., Stanford, CA (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States); von Hippel, Matt [Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada); McLeod, Andrew J. [SLAC National Accelerator Lab., Stanford, CA (United States)

2016-01-11

We use the hexagon function bootstrap to compute the ratio function which characterizes the next-to-maximally-helicity-violating (NMHV) six-point amplitude in planar N = 4 super-Yang-Mills theory at four loops. A powerful constraint comes from dual superconformal invariance, in the form of a Q^- differential equation, which heavily constrains the first derivatives of the transcendental functions entering the ratio function. At four loops, it leaves only a 34-parameter space of functions. Constraints from the collinear limits, and from the multi-Regge limit at the leading-logarithmic (LL) and next-to-leading-logarithmic (NLL) order, suffice to fix these parameters and obtain a unique result. We test the result against multi- Regge predictions at NNLL and N³LL, and against predictions from the operator product expansion involving one and two flux-tube excitations; all cross-checks are satisfied. We also study the analytical and numerical behavior of the parity-even and parity-odd parts on various lines and surfaces traversing the three-dimensional space of cross ratios. As part of this program, we characterize all irreducible hexagon functions through weight eight in terms of their coproduct. Furthermore, we provide representations of the ratio function in particular kinematic regions in terms of multiple polylogarithms.

The four-loop six-gluon NMHV ratio function

Energy Technology Data Exchange (ETDEWEB)

Dixon, Lance J. [SLAC National Accelerator Laboratory, Stanford University,Stanford, CA 94309 (United States); Walter Burke Institute for Theoretical Physics, California Institute of Technology,Pasadena, CA 91125 (United States); Hippel, Matt von [Perimeter Institute for Theoretical Physics,Waterloo, Ontario N2L 2Y5 (Canada); McLeod, Andrew J. [SLAC National Accelerator Laboratory, Stanford University,Stanford, CA 94309 (United States)

2016-01-11

We use the hexagon function bootstrap to compute the ratio function which characterizes the next-to-maximally-helicity-violating (NMHV) six-point amplitude in planar N=4 super-Yang-Mills theory at four loops. A powerful constraint comes from dual superconformal invariance, in the form of a Q̄ differential equation, which heavily constrains the first derivatives of the transcendental functions entering the ratio function. At four loops, it leaves only a 34-parameter space of functions. Constraints from the collinear limits, and from the multi-Regge limit at the leading-logarithmic (LL) and next-to-leading-logarithmic (NLL) order, suffice to fix these parameters and obtain a unique result. We test the result against multi-Regge predictions at NNLL and N{sup 3}LL, and against predictions from the operator product expansion involving one and two flux-tube excitations; all cross-checks are satisfied. We study the analytical and numerical behavior of the parity-even and parity-odd parts on various lines and surfaces traversing the three-dimensional space of cross ratios. As part of this program, we characterize all irreducible hexagon functions through weight eight in terms of their coproduct. We also provide representations of the ratio function in particular kinematic regions in terms of multiple polylogarithms.

The Reference Return Ratio

DEFF Research Database (Denmark)

Nicolaisen, Jeppe; Faber Frandsen, Tove

2008-01-01

The paper introduces a new journal impact measure called The Reference Return Ratio (3R). Unlike the traditional Journal Impact Factor (JIF), which is based on calculations of publications and citations, the new measure is based on calculations of bibliographic investments (references) and returns...... (citations). A comparative study of the two measures shows a strong relationship between the 3R and the JIF. Yet, the 3R appears to correct for citation habits, citation dynamics, and composition of document types - problems that typically are raised against the JIF. In addition, contrary to traditional...

K X-ray production cross sections, Kβ/Kα ratios, and radiative Auger ratios for protons impacting low-Z elements

International Nuclear Information System (INIS)

Cipolla, Sam J.

1999-01-01

A Cockcroft-Walton accelerator was used to produce 50-300 keV protons to excite characteristic X-rays from thick targets of elements from Z=21 to 32, using an efficiency-calibrated Si(Li) detector equipped with an ultra-thin window. X-ray production cross sections were determined and compared with prevailing theories. Special attention was paid to accounting for the radiative Auger effects (RAE) in the analysis of the X-ray energy spectra. Ratios of RAE to K α and K β intensities, as well as K β /K α ratios, will be compared to theoretical values

Fatigue crack closure behavior at high stress ratios

Science.gov (United States)

Turner, C. Christopher; Carman, C. Davis; Hillberry, Ben M.

1988-01-01

Fatigue crack delay behavior at high stress ratio caused by single peak overloads was investigated in two thicknesses of 7475-T731 aluminum alloy. Closure measurements indicated no closure occurred before or throughout the overload plastic zones following the overload. This was further substantiated by comparing the specimen compliance following the overload with the compliance of a low R ratio test when the crack was fully open. Scanning electron microscope studies revealed that crack tunneling and possibly reinitiation of the crack occurred, most likely a result of crack-tip blunting. The number of delay cycles was greater for the thinner mixed mode stress state specimen than for the thicker plane strain stress state specimen, which is similar to low R ratio test results and may be due to a larger plastic zone for the mixed mode cased.

Ratio analysis specifics of the family dairies' financial statements

Directory of Open Access Journals (Sweden)

Mitrović Aleksandra

2015-01-01

Full Text Available The subject of this paper is the evaluation of the financial analysis specifics of the dairy enterprises with a focus on the implementation of the ratio analysis of financial statements. The ratio analysis is a central part of financial analysis, since it is based on investigating the relationship between logically related items in the financial statements to assess the financial position of the observed enterprise and its earning capacity. Speaking about the reporting of financial performance in family dairies, the basis is created for displaying techniques of financial analysis, with a special indication on the specifics of their application in agricultural enterprises focusing on companies engaged in dairying. Applied in the paper is ratio analysis on the example of a dairy enterprise, i.e. a family dairy operating in Serbia. The ratio indicators are the basis for identifying relationships based on which by comparing the actual performance and certain business standards differences or variations are identified.

India’s Distorted Sex Ratio: Dire Consequences for Girls

Science.gov (United States)

Roberts, Lisa R.; Montgomery, Susanne B.

2017-01-01

Female gender discrimination related to cultural preference for males is a common global problem, especially in Asian countries. Numerous laws intended to prevent discrimination on the basis of gender have been passed in India, yet the distorted female-to-male sex ratio seems to show worsening tendencies. Using detailed, two-year longitudinal chart abstraction data about delivery records of a private mission hospital in rural India, we explored if hospital birth ratio data differed in comparison to regional data, and what demographic and contextual variables may have influenced these outcomes. Using quantitative chart abstraction and qualitative contextual data, study results showed the female-to-male ratio was lower than the reported state ratio at birth. In the context of India’s patriarchal structure, with its strong son preference, women are under tremendous pressure or coerced to access community-based, sex-selective identification and female fetus abortion. Nurses may be key to turning the tide. PMID:28286369

High conversion ratio plutonium recycle in pressurized water reactors

International Nuclear Information System (INIS)

Edlund, M.C.

1975-01-01

The use of Pu light water reactors in such a way as to minimise the depletion of Pu needed for future use, and therefore to reduce projected demands for U ore and U enrichment is envisaged. Fuel utilisation in PWRs could be improved by tightly-packed fuel rod lattices with conversion ratios of 0.8 to 0.9 compared with ratios of about 0.5 in Pu recycle designs using fuel to water volume ratios of currently operating PWRs. A conceptual design for the Babcock and Wilcox Company reactors now in operation is presented and for illustrative purposes thermalhydraulic design considerations and the reactor physics are described. Principle considerations in the mechanical design of the fuel assemblies are the effect of hydraulic forces, thermal expansion, and fission gas release. The impact of high conversion ratio plutionium recycle in separative work and natural U requirements for PWRs likely to be in operation by 1985 are examined. (U.K.)

The behavior of the likelihood ratio test for testing missingness

OpenAIRE

Hens, Niel; Aerts, Marc; Molenberghs, Geert; Thijs, Herbert

2003-01-01

To asses the sensitivity of conclusions to model choices in the context of selection models for non-random dropout, one can oppose the different missing mechanisms to each other; e.g. by the likelihood ratio tests. The finite sample behavior of the null distribution and the power of the likelihood ratio test is studied under a variety of missingness mechanisms. missing data; sensitivity analysis; likelihood ratio test; missing mechanisms

MARKETING MIX BY BED OCCUPANCY RATIO (BOR

Directory of Open Access Journals (Sweden)

Abdul Muhith

2017-04-01

Full Text Available Introduction: Bed Occupancy Ratio (BOR in RSI Arafah Mojosari during the last three years are at under ideal rate and the lowest of the three existing hospitals in the area of Mojosari. The purpose of this study was to determine the relationship marketing mix with Bed Occupancy Ratio in RSI Arafah Mojosari. Methods: This research uses analytic methods with crossectional approach. Variables in the study is marketing mix and Bed Occupancy Ratio (BOR. The population in this study were all patients hospitalized in the RSI Arafah Mojosari. Samples amounted 44 respondents taken by the Stratified random sampling technique. Data were collected using the questionnaire and analyzed using Fisher's Exact test. Result: The results obtained more than 50% of respondents (59.1% rate well against the marketing mix is developed by the hospital management and the majority of respondents (79.5% are in the treatment room that has a number BOR is not ideal. Fisher Exact test test results obtained probabililty value=0.02<0.05 so that H0 is rejected, which means there is a relationship marketing mix with the Bed Occupancy Ratio in RSI Arafah Mojosari. Discussion: Hospitals which able to develop the marketing mix very well, can attract consumers to use inpatient services at the hospital, with that BOR value will increase as the increased use of inpatient services. Hospital management must be able to formulate a good marketing mix strategy that hospital marketing objectives can be achieved. Conformity between service quality and service rates must be addressed, otherwise it extent of media promotions can attract patients to inpatient services.

THE CORRELATION BETWEEN THE AUTONOMY RATIO AND THE RETURN ON EQUITY

Directory of Open Access Journals (Sweden)

Daniel BRÎNDESCU – OLARIU

2014-11-01

Considering the relationship between the autonomy ratio and the bankruptcy risk as well as the relationship between the autonomy ratio and the return on equity, it is concluded that the optimum value of the autonomy ratio is placed within the interval [50%; 100%].

Sex ratio variation and sex determination in Urtica dioica

NARCIS (Netherlands)

Glawe, Grit Anja

2006-01-01

This thesis will first document on variation in progeny sex ratios among individual female plants of Urtica dioica at our field site in Meijendel (Chapter 2). Next, we show that there is also considerable sex ratio variation among male and female flowering shoots in 26 natural populations studied

Bankruptcy Prediction Based on the Autonomy Ratio

Directory of Open Access Journals (Sweden)

Daniel Brîndescu Olariu

2016-11-01

Full Text Available The theory and practice of the financial ratio analysis suggest the existence of a negative correlation between the autonomy ratio and the bankruptcy risk. Previous studies conducted on a sample of companies from Timis County (largest county in Romania confirm this hypothesis and recommend the autonomy ratio as a useful tool for measuring the bankruptcy risk two years in advance. The objective of the current research was to develop a methodology for measuring the bankruptcy risk that would be applicable for the companies from the Timis County (specific methodologies are considered necessary for each region. The target population consisted of all the companies from Timis County with annual sales of over 10,000 lei (aprox. 2,200 Euros. The research was performed over all the target population. The study has thus included 53,252 yearly financial statements from the period 2007 – 2010. The results of the study allow for the setting of benchmarks, as well as the configuration of a methodology of analysis. The proposed methodology cannot predict with perfect accuracy the state of the company, but it allows for a valuation of the risk level to which the company is subjected.

Canyon transfer neutron absorber to fissile material ratio analysis. Revision 1

International Nuclear Information System (INIS)

Clemmons, J.S.

1994-01-01

Waste tank fissile material and non-fissile material estimates are used to evaluate criticality safety for the existing sludge inventory and batches of sludge sent to Extended Sludge Processing (ESP). This report documents the weight ratios of several non-fissile waste constituents to fissile waste constituents from canyon reprocessing waste streams. Weight ratios of Fe, Mn, Al, Mi, and U-238 to fissile material are calculated from monthly loss estimates from the F and H Canyon Low Heat Waste (LHW) and High Heat Waste (HHW) streams. The monthly weight ratios for Fe, Mn and U-238 are then compared to calculated minimum safe weight ratios. Documented minimum safe weight ratios for Al and Ni to fissile material are currently not available. Total mass data for the subject sludge constituents is provided along with scatter plots of the monthly weight ratios for each waste stream

A simple analytical model for dynamics of time-varying target leverage ratios

Science.gov (United States)

Lo, C. F.; Hui, C. H.

2012-03-01

In this paper we have formulated a simple theoretical model for the dynamics of the time-varying target leverage ratio of a firm under some assumptions based upon empirical observations. In our theoretical model the time evolution of the target leverage ratio of a firm can be derived self-consistently from a set of coupled Ito's stochastic differential equations governing the leverage ratios of an ensemble of firms by the nonlinear Fokker-Planck equation approach. The theoretically derived time paths of the target leverage ratio bear great resemblance to those used in the time-dependent stationary-leverage (TDSL) model [Hui et al., Int. Rev. Financ. Analy. 15, 220 (2006)]. Thus, our simple model is able to provide a theoretical foundation for the selected time paths of the target leverage ratio in the TDSL model. We also examine how the pace of the adjustment of a firm's target ratio, the volatility of the leverage ratio and the current leverage ratio affect the dynamics of the time-varying target leverage ratio. Hence, with the proposed dynamics of the time-dependent target leverage ratio, the TDSL model can be readily applied to generate the default probabilities of individual firms and to assess the default risk of the firms.

Selected financial and operating ratios of public power systems

International Nuclear Information System (INIS)

Moody, D.

1993-01-01

In 1992, the American Public Power Association published its fourth report on financial and operating ratios. Based on 1990 data for the largest public power distribution systems, the report examined 21 categories of ratio indicators that can be used by public power distribution systems to assess their performance relative to the utilities of of comparable size and in the same geographic region. The 394 utilities summarized in the report are those that are required to file financial statements with the Energy Information Administration (EIA). Ratios were calculated from financial and operating data reported by utilities to the EIA. Data are presented for the following ratios: (1) revenue per kW/hr; (2) revenue for customer; (3) debt to total assets; (4) operating ratio; (5) current ratio; (6) times interest earned; (7) net income per revenue dollar; (8) uncollectible accounts per revenue dollar; (9) retail MW hr sales per manpower generation employee; (10) retail customers per nonpower generation employee; (11) total operation and maintenane expense per kW hr sold; (12) total operation and maintenance expense per retail customer; (13) total power supply expense kW hr sold; (14) purchased power cost per kW hr; (15) production expense per not kW hr; (16) retail customers for with reader; (17) distribution operation and maintenance expenses per retail customer; (18) distribution operation and maintenance expenses per circuit mile; (19) customer accounting, customer service and sales expenses per retail customers; (20) administration and general expenses per retail customer; (21) labor expense per worker-hour; (22) OSHA incidence rate; and (23) the system average interruptible duration index

Liquid and gas chromatography coupled to isotope ratio mass spectrometry for the determination of 13C-valine isotopic ratios in complex biological samples

NARCIS (Netherlands)

Godin, Jean-Philippe; Breuillé, Denis; Obled, Christiane; Papet, Isabelle; Schierbeek, Henk; Hopfgartner, Gérard; Fay, Laurent-Bernard

2008-01-01

On-line gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is commonly used to measure isotopic ratios at natural abundance as well as for tracer studies in nutritional and medical research. However, high-precision (13)C isotopic enrichment can also be measured by liquid

Uranium isotope ratio measurements in field settings

International Nuclear Information System (INIS)

Shaw, R.W.; Barshick, C.M.; Young, J.P.; Ramsey, J.M.

1997-01-01

The authors have developed a technique for uranium isotope ratio measurements of powder samples in field settings. Such a method will be invaluable for environmental studies, radioactive waste operations, and decommissioning and decontamination operations. Immediate field data can help guide an ongoing sampling campaign. The measurement encompasses glow discharge sputtering from pressed sample hollow cathodes, high resolution laser spectroscopy using conveniently tunable diode lasers, and optogalvanic detection. At 10% 235 U enrichment and above, the measurement precision for 235 U/( 235 U+ 238 U) isotope ratios was ±3%; it declined to ±15% for 0.3% (i.e., depleted) samples. A prototype instrument was constructed and is described

Poisson's ratio and Young's modulus of lipid bilayers in different phases

Directory of Open Access Journals (Sweden)

Tayebeh eJadidi

2014-04-01

Full Text Available A general computational method is introduced to estimate the Poisson's ratio for membranes with small thickness.In this method, the Poisson's ratio is calculated by utilizing a rescaling of inter-particle distancesin one lateral direction under periodic boundary conditions. As an example for the coarse grained lipid model introduced by Lenz and Schmid, we calculate the Poisson's ratio in the gel, fluid, and interdigitated phases. Having the Poisson's ratio, enable us to obtain the Young's modulus for the membranes in different phases. The approach may be applied to other membranes such as graphene and tethered membranes in orderto predict the temperature dependence of its Poisson's ratio and Young's modulus.

Influence of void ratio on thermal performance of heat pipe receiver

International Nuclear Information System (INIS)

Gui Xiaohong; Tang Dawei; Liang Shiqiang; Lin Bin; Yuan Xiugan

2012-01-01

Highlights: ► The temperature gradient increases significantly and the utility ratio of PCM decreases obviously as void ratio increases. ► Void cavity influences the process of phase change greatly. ► PCM melts slowly during sunlight periods and freezes slowly during eclipse periods as void ratio increases. ► The temperature gradient of PCM zone is very significant with the effect of void cavity. - Abstract: In this paper, influence of void ratio on thermal performance of heat pipe receiver under microgravity is numerically simulated. Accordingly, mathematical model is set up. Numerical method is offered. The temperature field of Phase Change Material (PCM) canister is shown. Numerical results are compared with numerical ones of National Aeronautics and Space Administration (NASA). Numerical results show that the temperature gradient increases significantly and the utility ratio of PCM decreases obviously as void ratio increases. Void cavity influences the process of phase change greatly. PCM melts slowly during sunlight periods and freezes slowly during eclipse periods as void ratio increases. The thermal resistance of void cavity is much bigger than that of PCM canister wall. Void cavity prevents the heat transfer between PCM zone and canister wall. The temperature gradient of PCM zone is very significant with the effect of void cavity. So the thermal stress of heat pipe receiver may increase, and the lifetime may decrease as void ratio increases.

BENEFITS AND CHALLENGES OF VARIABLE COMPRESSION RATIO AT DIESEL ENGINES

OpenAIRE

Radivoje B Pešić; Saša T Milojević; Stevan P Veinović

2010-01-01

The compression ratio strongly affects the working process and provides an exceptional degree of control over engine performance. In conventional internal combustion engines, the compression ratio is fixed and their performance is therefore a compromise between conflicting requirements. One fundamental problem is that drive units in the vehicles must successfully operate at variable speeds and loads and in different ambient conditions. If a diesel engine has a fixed compression ratio, a minim...

Updating Financial Ratios: Seeking Greater Understanding, Precision, and Practicality.

Science.gov (United States)

Jenny, Hans H.; Minter, W. John

1993-01-01

Modifications to current methods of calculating and reporting financial ratios are outlined for college managers. The modified ratios, felt to be more realistic, are illustrated with applications in three areas: (1) student revenues; (2) endowment and other investment income; and (3) public and private gifts, grants, and contracts revenue. (MSE)

Analysis of root surface properties by fluorescence/Raman intensity ratio.

Science.gov (United States)

Nakamura, Shino; Ando, Masahiro; Hamaguchi, Hiro-O; Yamamoto, Matsuo

2017-11-01

The aim of this study is to evaluate the existence of residual calculus on root surfaces by determining the fluorescence/Raman intensity ratio. Thirty-two extracted human teeth, partially covered with calculus on the root surface, were evaluated by using a portable Raman spectrophotometer, and a 785-nm, 100-mW laser was applied for fluorescence/Raman excitation. The collected spectra were normalized to the hydroxyapatite Raman band intensity at 960 cm -1 . Raman spectra were recorded from the same point after changing the focal distance of the laser and the target radiating angle. In seven teeth, the condition of calculus, cementum, and dentin were evaluated. In 25 teeth, we determined the fluorescence/Raman intensity ratio following three strokes of debridement. Raman spectra collected from the dentin, cementum, and calculus were different. After normalization, spectra values were constant. The fluorescence/Raman intensity ratio of calculus region showed significant differences compared to the cementum and dentin (p Raman intensity ratio decreased with calculus debridement. For this analysis, the delta value was defined as the difference between the values before and after three strokes, with the final 2 delta values close to zero, indicating a gradual asymptotic curve and the change in intensity ratio approximating that of individual constants. Fluorescence/Raman intensity ratio was effectively used to cancel the angle- and distance-dependent fluctuations of fluorescence collection efficiency during measurement. Changes in the fluorescence/Raman intensity ratio near zero suggested that cementum or dentin was exposed, and calculus removed.

Arbitrary-ratio power splitter based on nonlinear multimode interference coupler

International Nuclear Information System (INIS)

Tajaldini, Mehdi; Jafri, Mohd Zubir Mat

2015-01-01

We propose an ultra-compact multimode interference (MMI) power splitter based on nonlinear effects from simulations using nonlinear modal propagation analysis (NMPA) cooperation with finite difference Method (FDM) to access free choice of splitting ratio. Conventional multimode interference power splitter could only obtain a few discrete ratios. The power splitting ratio may be adjusted continuously while the input set power is varying by a tunable laser. In fact, using an ultra- compact MMI with a simple structure that is launched by a tunable nonlinear input fulfills the problem of arbitrary-ratio in integrated photonics circuits. Silicon on insulator (SOI) is used as the offered material due to the high contrast refractive index and Centro symmetric properties. The high-resolution images at the end of the multimode waveguide in the simulated power splitter have a high power balance, whereas access to a free choice of splitting ratio is not possible under the linear regime in the proposed length range except changes in the dimension for any ratio. The compact dimensions and ideal performance of the device are established according to optimized parameters. The proposed regime can be extended to the design of M×N arbitrary power splitters ratio for programmable logic devices in all optical digital signal processing. The results of this study indicate that nonlinear modal propagation analysis solves the miniaturization problem for all-optical devices based on MMI couplers to achieve multiple functions in a compact planar integrated circuit and also overcomes the limitations of previously proposed methods for nonlinear MMI

Arbitrary-ratio power splitter based on nonlinear multimode interference coupler

Energy Technology Data Exchange (ETDEWEB)

Tajaldini, Mehdi [School of Physics, Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia); Young Researchers and Elite Club, Baft Branch, Islamic Azad University, Baft (Iran, Islamic Republic of); Jafri, Mohd Zubir Mat [School of Physics, Universiti Sains Malaysia, 11800 Pulau Pinang (Malaysia)

2015-04-24

We propose an ultra-compact multimode interference (MMI) power splitter based on nonlinear effects from simulations using nonlinear modal propagation analysis (NMPA) cooperation with finite difference Method (FDM) to access free choice of splitting ratio. Conventional multimode interference power splitter could only obtain a few discrete ratios. The power splitting ratio may be adjusted continuously while the input set power is varying by a tunable laser. In fact, using an ultra- compact MMI with a simple structure that is launched by a tunable nonlinear input fulfills the problem of arbitrary-ratio in integrated photonics circuits. Silicon on insulator (SOI) is used as the offered material due to the high contrast refractive index and Centro symmetric properties. The high-resolution images at the end of the multimode waveguide in the simulated power splitter have a high power balance, whereas access to a free choice of splitting ratio is not possible under the linear regime in the proposed length range except changes in the dimension for any ratio. The compact dimensions and ideal performance of the device are established according to optimized parameters. The proposed regime can be extended to the design of M×N arbitrary power splitters ratio for programmable logic devices in all optical digital signal processing. The results of this study indicate that nonlinear modal propagation analysis solves the miniaturization problem for all-optical devices based on MMI couplers to achieve multiple functions in a compact planar integrated circuit and also overcomes the limitations of previously proposed methods for nonlinear MMI.

Getting past nature as a guide to the human sex ratio.

Science.gov (United States)

Murphy, Timothy F

2013-05-01

Sex selection of children by pre-conception and post-conception techniques remains morally controversial and even illegal in some jurisdictions. Among other things, some critics fear that sex selection will distort the sex ratio, making opposite-sex relationships more difficult to secure, while other critics worry that sex selection will tilt some nations toward military aggression. The human sex ratio varies depending on how one estimates it; there is certainly no one-to-one correspondence between males and females either at birth or across the human lifespan. Complications about who qualifies as 'male' and 'female' complicate judgments about the ratio even further. Even a judiciously estimated sex ratio does not have, however, the kind of normative status that requires society to refrain from antenatal sex selection. Some societies exhibit lopsided sex ratios as a consequence of social policies and practices, and pragmatic estimates of social needs are a better guide to what the sex ratio should be, as against looking to 'nature'. The natural sex ratio cannot be a sound moral basis for prohibiting parents from selecting the sex of their children, since it ultimately lacks any normative meaning for social choices. © 2011 Blackwell Publishing Ltd.

Characterization of low active ghrelin ratio in patients with advanced pancreatic cancer.

Science.gov (United States)

Miura, Tomofumi; Mitsunaga, Shuichi; Ikeda, Masafumi; Ohno, Izumi; Takahashi, Hideaki; Suzuki, Hidetaka; Irisawa, Ai; Kuwata, Takeshi; Ochiai, Atsushi

2018-05-18

Acyl ghrelin is an orexigenic peptide. Active ghrelin ratio, the ratio of acyl ghrelin to total ghrelin, has an important role in physiological functions and gastrointestinal symptoms. However, low active ghrelin ratio-related characteristics, gastrointestinal symptoms, and chemotherapy-induced gastrointestinal toxicity in patients with advanced pancreatic cancer have not been previously evaluated. The goal of this study was to identify low active ghrelin ratio-related factors in treatment-naïve advanced pancreatic cancer patients. Patients with treatment-naïve advanced pancreatic cancer were eligible for inclusion in this study. Active ghrelin ratio and clinical parameters of patients were prospectively recorded. Factors correlated with low active ghrelin ratio and survival were analyzed. In total, 92 patients were analyzed. Low active ghrelin ratio-related factors were advanced age (P advanced pancreatic cancer.

PROFITABILITY RATIO AS A TOOL FOR BANKRUPTCY PREDICTION

OpenAIRE

Daniel BRÎNDESCU – OLARIU

2016-01-01

The current study evaluates the potential of the profitability ratio in predicting corporate bankruptcy. The research is focused on Romanian companies, with the targeted event being represented by the manifestation of bankruptcy 2 years after the date of the financial statements of reference. All tests were conducted over 2 paired samples of 1176 Romanian companies. The methodology employed in evaluating the potential of the profitability ratio was based on the Area Under the ROC Curve (0.663...

The labor/land ratio and India's caste system

OpenAIRE

Duleep, Harriet

2012-01-01

This paper proposes that India’s caste system and involuntary labor were joint responses by a nonworking landowning class to a low labor/land ratio in which the rules of the caste system supported the institution of involuntary labor. The hypothesis is tested in two ways: longitudinally, with data from ancient religious texts, and cross-sectionally, with twentieth-century statistics on regional population/land ratios linked to anthropological measures of caste-system rigidity. Both the longit...

Ratio of critical quantities related to Hawking temperature–entanglement entropy criticality

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Jie-Xiong Mo

2017-10-01

Full Text Available We revisit the Hawking temperature–entanglement entropy criticality of the d-dimensional charged AdS black hole with our attention concentrated on the ratio TcδSEcQc. Comparing the results of this paper with those of the ratio TcScQc, one can find both the similarities and differences. These two ratios are independent of the characteristic length scale l and dependent on the dimension d. These similarities further enhance the relation between the entanglement entropy and the Bekenstein–Hawking entropy. However, the ratio TcδSEcQc also relies on the size of the spherical entangling region. Moreover, these two ratios take different values even under the same choices of parameters. The differences between these two ratios can be attributed to the peculiar property of the entanglement entropy since the research in this paper is far from the regime where the behavior of the entanglement entropy is dominated by the thermal entropy.

Rocket nozzle expansion ratio analysis for dual-fuel earth-to-orbit vehicles

Science.gov (United States)

Martin, James A.

1989-01-01

Results are reported from a recent study of the effects of Space Shuttle Main Engine expansion ratio modifications, in the cases of both single-stage and two-stage systems. Two-position nozzles were employed; after varying the lower expansion ratio while the higher was held constant at 120, the lower expansion ratio was held constant at 40 or 60 while the higher expansion ratio was varied. The expansion ratios for minimum vehicle dry mass are different for single-stage and two-stage systems. For two-stage systems, a single expansion ratio of 77.5 provides a lower dry mass than any two-position nozzle.

Nilai Rerata Vascular Pedicle Width, Vascular Pedicle-Cardiac Ratio Vascular Pedicle-Thoracic Ratio Orang Dewasa Normal Indonesia Studi di RS dr. Cipto Mangunkusomo

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Rommy Zunera

2016-03-01

Full Text Available Vascular pedicle width (VPW adalah jarak tepi luar vena kava superior ke tepi luar arteri subklavia kiri. Pemeriksaan VPW di foto toraks bersifat non-invasif, cepat dan mudah untuk memprediksi hipervolemia.Penelitian ini bertujuan untuk mengetahui rerata nilai VPW orang dewasa normal Indonesia. VPW diukurdengan dua metode: pertama pengukuran VPW tunggal yang akurasinya terbatas di foto toraks digital karenarelatif tidak dipengaruhi faktor magnifikasi. Metode kedua untuk foto toraks nondigital yaitu pengukuranrasio:vascular pedicle-cardiac ratio (VPCR dan vascular pedicle-thoracic ratio (VPTR. Pengukuran serupadilakukan terhadap  topogram CT scan toraks AP terlentang dan CT scan toraks lalu dibandingkan akurasipengukuran di topogram dengan CT scan  toraks sebagai standar baku. Sampel terdiri atas 104 foto toraksPA subyek normal dan 103 CT scan  toraks subyek terpilih. Pada pemeriksaan toraks PA didapatkan rerata VPW 48,0±5,5mm, rerata VPCR 40,3±4,6%, dan rerata VPTR 17,2±1,7%. Pada pemeriksaan topogram CTscan didapatkan rerata VPW 50,3±6,2mm, rerata VPTR 45±5,1%, dan rerata VPTR 19,8±2,5%. Rerata VPWpada CT scan toraks 50,4±6,1mm. Pengukuran di foto toraks AP 10% lebih besar dibandingkan pada fototoraks PA dan pengukuranVPW di foto toraks terbukti memiliki akurasi  tinggi. Kata kunci: fototoraks, vascular pedicle width, vascular pedicle-cardiac ratio, vascular pedicle-thoracic ratio, hipervolemia.   The Mean Value of Vascular Pedicle Width, Vascular Pedicle-Cardiac Ratio,Vascular Pedicle-Thoracic Ratio of Normal Indonesian Adult Study In dr. Cipto Mangunkusomo Hospital Abstract Vascular pedicle width (VPW is the distance, from a perpendicular line at the takeoff point of the left subclavian artery off the aorta to the point at which the superior vena cava. Measurement of VPW on chestx-ray is relatively non-invasive, fast and easy technique as  hypervolemia predictor. The purpose of thisstudy is to know the mean VPW value of normal

Positron Annihilation Ratio Spectroscopy (PsARS) Applied to Positronium Formation Studies

Science.gov (United States)

2010-03-01

Positron Annihilation Ratio Spectroscopy (PsARS). These experimental techniques have been used for a variety of military and civilian applications ... POSITRON ANNIHILATION RATIO SPECTROSCOPY (PsARS) APPLIED TO POSITRONIUM FORMATION STUDIES THESIS...of Defense, or the United States Government. AFIT/GNE/ENP/10-M07 POSITRON ANNIHILATION RATIO SPECTROSCOPY

Financial and Staffing Ratio Analysis: Predicting Fiscal Distress in School Districts.

Science.gov (United States)

Lee, Robert Alan

1983-01-01

From analysis of data from 579 school districts it is concluded that financial ratios have the ability to forecast fiscal distress a year in advance. Liquidity ratios and salary and fringe benefit ratios were found to be strong forecasters, while per pupil expenditure data had little predictive value. (MJL)

On the electron-ion temperature ratio established by collisionless shocks

Science.gov (United States)

Vink, Jacco; Broersen, Sjors; Bykov, Andrei; Gabici, Stefano

2015-07-01

Astrophysical shocks are often collisionless shocks, in which the changes in plasma flow and temperatures across the shock are established not through Coulomb interactions, but through electric and magnetic fields. An open question about collisionless shocks is whether electrons and ions each establish their own post-shock temperature (non-equilibration of temperatures), or whether they quickly equilibrate in the shock region. Here we provide a simple, thermodynamic, relation for the minimum electron-ion temperature ratios that should be expected as a function of Mach number. The basic assumption is that the enthalpy-flux of the electrons is conserved separately, but that all particle species should undergo the same density jump across the shock, in order for the plasma to remain charge neutral. The only form of additional electron heating that we allow for is adiabatic heating, caused by the compression of the electron gas. These assumptions result in an analytic treatment of expected electron-ion temperature ratio that agrees with observations of collisionless shocks: at low sonic Mach numbers, Ms ≲ 2, the electron-ion temperature ratio is close to unity, whereas for Mach numbers above Ms ≈ 60 the electron-ion temperature ratio asymptotically approaches a temperature ratio of Te/Ti = me/ ⟨ mi ⟩. In the intermediate Mach number range the electron-ion temperature ratio scales as Te/Ti ∝ Ms-2. In addition, we calculate the electron-ion temperature ratios under the assumption of adiabatic heating of the electrons only, which results in a higher electron-ion temperature ratio, but preserves the Te/Ti ∝ Ms-2 scaling. We also show that for magnetised shocks the electron-ion temperature ratio approaches the asymptotic value Te/Ti = me/ ⟨ mi ⟩ for lower magnetosonic Mach numbers (Mms), mainly because for a strongly magnetised shock the sonic Mach number is larger than the magnetosonic Mach number (Mms ≤ Ms). The predicted scaling of the electron

Calculation of the Cardiothoracic Ratio from Portable Anteroposterior Chest Radiography

Science.gov (United States)

Chon, Sung Bin; Oh, Won Sup; Cho, Jun Hwi; Kim, Sam Soo

2011-01-01

Cardiothoracic ratio (CTR), the ratio of cardiac diameter (CD) to thoracic diameter (TD), is a useful screening method to detect cardiomegaly, but is reliable only on posteroanterior chest radiography (chest PA). We performed this cross-sectional 3-phase study to establish reliable CTR from anteroposterior chest radiography (chest AP). First, CDChest PA/CDChest AP ratios were determined at different radiation distances by manipulating chest computed tomography to simulate chest PA and AP. CDChest PA was inferred from multiplying CDChest AP by this ratio. Incorporating this CD and substituting the most recent TDChest PA, we calculated the 'corrected' CTR and compared it with the conventional one in patients who took both the chest radiographies. Finally, its validity was investigated among the critically ill patients who performed portable chest AP. CDChest PA/CDChest AP ratio was {0.00099 × (radiation distance [cm])} + 0.79 (n = 61, r = 1.00, P chest AP with an available previous chest PA. This might help physicians detect congestive cardiomegaly for patients undergoing portable chest AP. PMID:22065900

12 CFR 567.8 - Leverage ratio.

Science.gov (United States)

2010-01-01

... anticipating or experiencing significant growth and have well-diversified risks, including no undue interest rate risk exposure, excellent asset quality, high liquidity, and good earnings. (b) For all savings... capital ratios may be required if warranted by the particular circumstances or risk profiles of an...

The Steiner ratio for points on a triangular lattice

African Journals Online (AJOL)

design of integrated circuit boards, communication networks, power networks and pipelines of minimum cost. In such applications the Steiner ratio is an indication of how badly a minimum spanning tree performs compared to a Steiner minimal tree. In this paper a short proof is presented for the Steiner ratio for points on a ...

Implications of Fast Reactor Transuranic Conversion Ratio

International Nuclear Information System (INIS)

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

2010-01-01

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 float 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, 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 found among the higher actinides, so the neutron emission varies much stronger with CR, about three orders of magnitude.

Design and development of a digital phase ratio meter

Energy Technology Data Exchange (ETDEWEB)

Majee, B C [Reactor Control Division, Bhabha Atomic Research Centre, Mumbai (India); Roy, S B; Meghal, A M [Uranium Extraction Division, Bhabha Atomic Research Centre, Mumbai (India)

1994-06-01

Uranium purification at Uranium Metal Plant is being carried out using solvent extraction process. The feed is aqueous uranyl nitrate solution with 2-4% insoluble silica particles. The solvent is tri-butyl phosphate diluted with commercial grade kerosene. Extraction is conducted in a slurry extractor equipment using compressed air as mixing and solution-interstage transferring medium. To ensure the organic continuous mode in the mixer and to avoid stable emulsion formation, organic to aqueous ratio maintained in each mixer is 10 to 12 whereas optimum extraction process requires an overall organic to aqueous ratio of 2. Therefore, a high volume of internal recirculation of organic is being arranged by the air-lift in mixers. For a smooth, continuous efficient extraction, mixer organic to aqueous ratio is a very critical parameter and it is required to be monitored periodically to take corrective actions during the operation by controlling the compressed air flow rate. Trials were conducted to select a suitable method of autocontrol of this phase ratio and a system has been designed for this purpose. (author). 3 figs., 1 tab.

The effect of financial ratios on systematic risk index

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Ali Faez

2013-11-01

Full Text Available This paper investigates the relationship between financial ratios and indicator of systemic risk in the Tehran Stock Exchange. The study selects 73 manufacturing companies of the Tehran Stock Exchange market over the period 2003-2010. The study first calculates the independent variables in the form of financial ratios and then the ratios affecting the systematic risk index are extracted using entropy method. The output of this stage is the introduction of five influential financial indicators as the independent variables of the study. Using t-test and Pearson correlation coefficient the rate of independent variables effect on the systematic risk index is evaluated and finally, using stepwise regression method, the effect of independent variables on the dependent variable is examined. According to results of our survey, the correlation coefficient of such indices as “the ratio of stock price to the profit of each share”, “Current ratio”, “each share profit ratio” and “the stockholders rights return ratio” have respectively the highest correlation with the systematic risk index.

Standardized binomial models for risk or prevalence ratios and differences.

Science.gov (United States)

Richardson, David B; Kinlaw, Alan C; MacLehose, Richard F; Cole, Stephen R

2015-10-01

Epidemiologists often analyse binary outcomes in cohort and cross-sectional studies using multivariable logistic regression models, yielding estimates of adjusted odds ratios. It is widely known that the odds ratio closely approximates the risk or prevalence ratio when the outcome is rare, and it does not do so when the outcome is common. Consequently, investigators may decide to directly estimate the risk or prevalence ratio using a log binomial regression model. We describe the use of a marginal structural binomial regression model to estimate standardized risk or prevalence ratios and differences. We illustrate the proposed approach using data from a cohort study of coronary heart disease status in Evans County, Georgia, USA. The approach reduces problems with model convergence typical of log binomial regression by shifting all explanatory variables except the exposures of primary interest from the linear predictor of the outcome regression model to a model for the standardization weights. The approach also facilitates evaluation of departures from additivity in the joint effects of two exposures. Epidemiologists should consider reporting standardized risk or prevalence ratios and differences in cohort and cross-sectional studies. These are readily-obtained using the SAS, Stata and R statistical software packages. The proposed approach estimates the exposure effect in the total population. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Correlates of lung/heart ratio of thallium-201 in coronary artery disease

International Nuclear Information System (INIS)

Homma, S.; Kaul, S.; Boucher, C.A.

1987-01-01

We studied 306 patients with chest pain (262 with coronary artery disease and 44 with no coronary artery disease) to determine which of 23 clinical, exercise, thallium, and angiographic variables best discriminate between patients with increased lung/heart ratios of thallium versus those with normal ratios. Normal lung/heart ratio values were defined using an additional 45 subjects with less than 1% probability of coronary artery disease. The number of diseased vessels was the best discriminator between patients with increased ratios versus those with normal ratios. Double product at peak exercise, number of segments with abnormal wall motion, patient gender, and duration of exercise were also significant discriminators. Using discriminant function analysis these variables could correctly identify 81% of cases with increased lung/heart ratios and 72% of cases with normal ratios. These results indicate that an increased lung/heart ratio of thallium reflects exercise-induced left ventricular dysfunction and affords a better understanding of why this thallium parameter is a powerful prognostic indicator in patients with chest pain

Forecasting Fire Insurance Loss Ratio in Misr Insurance Company

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Tarek TAHA

2017-06-01

Full Text Available Loss ratio is one of the most important indicator that has many strategic decisions applications, such as pricing, underwriting, investment, reinsurance and reserving decisions. It serves as an early warning of financial solvency of insurance companies and it can be judged on the strength of the financial position of these companies. The aim of this study is to identify the reliable time series-forecasting model to forecast loss ratio estimates of fire segment in Misr insurance company. Box-Jenkins Analysis is applied on actual reported loss ratios data for Misr insurance company for the period 1980/1981– 2013/2014. The study concludes that the best forecasting model is ARMA(1,1.

Development of air fuel ratio sensor; A/F sensor no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Sakawa, T; Hori, M [Denso Corp., Aichi (Japan); Nakamura, Y [Toyota Motor Corp., Aichi (Japan)

1997-10-01

The Air Fuel Ratio Sensor (A/F sensor), which is applied to a 1997 model year Low Emission Vehicle (LEV) was developed. This sensor enables the detection of the exhaust gas air fuel ratio, both lean and rich of stoichiometric. It has an effective air fuel ratio range from 12 to 18 as required for LEV regulation. It has the fast light off, - within 20 seconds - to minimize exhaust hydrocarbon content. Further, it has fast response time, less than 200 msec, to improve the air fuel ratio controllability. 3 refs., 7 figs.

High extinction ratio integrated optical modulator for quantum telecommunication systems

Science.gov (United States)

Tronev, A.; Parfenov, M.; Agruzov, P.; Ilichev, I.; Shamray, A.

2018-01-01

A method for increasing the extinction ratio of integrated optical Mach-Zehnder modulators based on LiNbO3 via the photorefractive effect is proposed. The influence of the photorefractive effect on the X- and Y-splitters of intensity modulators is experimentally studied. An increase in the modulator extinction ratio by 17 dB (from 30 to 47 dB) is obtained. It is shown that fabricated modulators with a high extinction ratio are important for quantum key distribution systems.

Calibrating recruitment estimates for mourning doves from harvest age ratios

Science.gov (United States)

Miller, David A.; Otis, David L.

2010-01-01

We examined results from the first national-scale effort to estimate mourning dove (Zenaida macroura) age ratios and developed a simple, efficient, and generalizable methodology for calibrating estimates. Our method predicted age classes of unknown-age wings based on backward projection of molt distributions from fall harvest collections to preseason banding. We estimated 1) the proportion of late-molt individuals in each age class, and 2) the molt rates of juvenile and adult birds. Monte Carlo simulations demonstrated our estimator was minimally biased. We estimated model parameters using 96,811 wings collected from hunters and 42,189 birds banded during preseason from 68 collection blocks in 22 states during the 2005–2007 hunting seasons. We also used estimates to derive a correction factor, based on latitude and longitude of samples, which can be applied to future surveys. We estimated differential vulnerability of age classes to harvest using data from banded birds and applied that to harvest age ratios to estimate population age ratios. Average, uncorrected age ratio of known-age wings for states that allow hunting was 2.25 (SD 0.85) juveniles:adult, and average, corrected ratio was 1.91 (SD 0.68), as determined from harvest age ratios from an independent sample of 41,084 wings collected from random hunters in 2007 and 2008. We used an independent estimate of differential vulnerability to adjust corrected harvest age ratios and estimated the average population age ratio as 1.45 (SD 0.52), a direct measure of recruitment rates. Average annual recruitment rates were highest east of the Mississippi River and in the northwestern United States, with lower rates between. Our results demonstrate a robust methodology for calibrating recruitment estimates for mourning doves and represent the first large-scale estimates of recruitment for the species. Our methods can be used by managers to correct future harvest survey data to generate recruitment estimates for use in

Long‐term trends in fall age ratios of black brant

Science.gov (United States)

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

Characterizations of Soil Profiles Through Electric Resistivity Ratio

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Chik Z

2015-04-01

Full Text Available This paper presents how near surface soil characteristics are obtained through soil electric resistivity ratio from soil apparent resistivity profile. In recent advances of electrical sensors, soil apparent resistivity is implemented as nondestructive method for obtaining near surface soil profile. Although geo-electric techniques offer an improvement to traditional soil sampling methods, the resulting data are still often misinterpreted for obtaining soil characteristics through apparent electrical resistivity in the field. Because, soil resistivity as before rain and after rain are changeable due to the presence of more moisture contents in field investigations. In this study, the parameter of soil electric resistivity ratio is incorporated to obtain reliable near surface soil profiles from apparent resistivity of adjacent two layers in soil. The variations of potential differences are taken into account for using four probes method to get the soil apparent resistivity profile. The research is significant for simpler and faster soil characterizations using resistivity ratio of apparent resistivity in soil investigations.

Sex ratio, gonadal development and fecundity of the grunt ...

African Journals Online (AJOL)

The sex ratio, gonadosomatic index, stages of gonadal development and fecundity of the grunt, Pomadasys jubelini in the New Calabar-Bonny River were investigated. P. jubelini had a sex ratio of 1: 2.1 (male to female). Gonadosomatic index ranged from 0.33 to 7.29% with a mean of 2.89+0.08%. High gonadosomatic ...

Radiographic measurement of the cardiothoracic ratio in pet macaques from Sulawesi, Indonesia

Energy Technology Data Exchange (ETDEWEB)

Schillaci, Michael A. [Department of Social Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4 (Canada)], E-mail: schillaci@utsc.utoronto.ca; Parish, Stephanie [Department of Social Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4 (Canada); Jones-Engel, Lisa [National Primate Research Center, University of Washington, 1705 N.E. Pacific Street, Seattle, WA 98195 (United States)

2009-11-15

The relative size of the heart, as measured by the cardiothoracic ratio, is often used as an index of ventricular hypertrophy-an important measure of myocardial pathophysiology in human primates. Despite its widespread use in human medicine, use of the cardiothoracic ratio in nonhuman primate veterinary medicine has been poorly documented. This report describes the results of our radiographic study of the cardiothoracic ratio in a sample of pet monkeys from Sulawesi, Indonesia. We assessed the effects of age and sex on cardiothoracic ratios, and compared our estimates with those presented in the literature for the Formosan macaque (Macaca cyclopis). Our results indicated a significant difference between the Sulawesi macaque species groupings in cardiothoracic ratios. Sex and age-related differences were not significant. Comparisons of cardiothoracic ratios with published ratios indicated similarity between M. cyclopis and Macaca nigra, but not between M. cyclopis and Macaca tonkeana.

Radiographic measurement of the cardiothoracic ratio in pet macaques from Sulawesi, Indonesia

International Nuclear Information System (INIS)

Schillaci, Michael A.; Parish, Stephanie; Jones-Engel, Lisa

2009-01-01

The relative size of the heart, as measured by the cardiothoracic ratio, is often used as an index of ventricular hypertrophy-an important measure of myocardial pathophysiology in human primates. Despite its widespread use in human medicine, use of the cardiothoracic ratio in nonhuman primate veterinary medicine has been poorly documented. This report describes the results of our radiographic study of the cardiothoracic ratio in a sample of pet monkeys from Sulawesi, Indonesia. We assessed the effects of age and sex on cardiothoracic ratios, and compared our estimates with those presented in the literature for the Formosan macaque (Macaca cyclopis). Our results indicated a significant difference between the Sulawesi macaque species groupings in cardiothoracic ratios. Sex and age-related differences were not significant. Comparisons of cardiothoracic ratios with published ratios indicated similarity between M. cyclopis and Macaca nigra, but not between M. cyclopis and Macaca tonkeana.

The impact of student-faculty ratio on pharmacy faculty scholarship.

Science.gov (United States)

Benavides, Sandra; Garcia, Angela S; Caballero, Joshua; Wolowich, William R

2010-10-11

To determine the relationship and impact of student-faculty ratio on scholarship of pharmacy faculty members. The number and rank of faculty members, pharmacy program characteristics, and faculty productivity data were collected to determine the impact of student-faculty ratio on faculty scholarship. Faculty scholarship was not predicted by student-faculty ratio. Factors impacting positively on faculty productivity included National Institutes of Health funding; presence of clinical associate professors, instructors, and lecturers; and programs located in public universities. Faculty productivity is not related to the student-faculty ratio, wherein more faculty members and fewer students equates to increased scholarship. However, public universities may have different infrastructures which are associated with greater academic productivity compared to private institutions. Additionally, utilizing instructors and clinical or nontenure-track faculty members can significantly increase scholarship among faculty members.

Remarks on 'Poisson ratio beyond the limits of the elasticity theory'

International Nuclear Information System (INIS)

Wojciechowski, K.W.

2002-12-01

The non-chiral, elastically isotropic model exhibits Poison ratios in the range -1 ≤ σ ≤ 1 without any molecular rotation. The centres of discs-atoms are replaced in the vertices of a perfect triangle of the side length equal to σ. The positive sign of the Lame constant λ is not necessary for the stability of an isotropic system at any dimensionality. As the upper limit for the Poisson ratio in 2D isotropic systems is 1, crystalline or polycrystalline 2D systems can be obtained having the Poisson ratio exceeding 1/2. Both the traditional theory of elasticity and the Cosserat one exclude Poisson ratios exceeding 1/2 in 3D isotropic systems. Neighter anisotropy nor rotation are necessary to obtain extreme values of the Poisson ratio (author)

Model Persamaan Massa Karbon Akar Pohon dan Root-Shoot Ratio Massa Karbon (Equation Models of Tree Root Carbon Mass and Root-Shoot Carbon Mass Ratio

Directory of Open Access Journals (Sweden)

Elias .

2011-03-01

Full Text Available The case study was conducted in the area of Acacia mangium plantation at BKPH Parung Panjang, KPH Bogor. The objective of the study was to formulate equation models of tree root carbon mass and root to shoot carbon mass ratio of the plantation. It was found that carbon content in the parts of tree biomass (stems, branches, twigs, leaves, and roots was different, in which the highest and the lowest carbon content was in the main stem of the tree and in the leaves, respectively. The main stem and leaves of tree accounted for 70% of tree biomass. The root-shoot ratio of root biomass to tree biomass above the ground and the root-shoot ratio of root biomass to main stem biomass was 0.1443 and 0.25771, respectively, in which 75% of tree carbon mass was in the main stem and roots of tree. It was also found that the root-shoot ratio of root carbon mass to tree carbon mass above the ground and the root-shoot ratio of root carbon mass to tree main stem carbon mass was 0.1442 and 0.2034, respectively. All allometric equation models of tree root carbon mass of A. mangium have a high goodness-of-fit as indicated by its high adjusted R2.Keywords: Acacia mangium, allometric, root-shoot ratio, biomass, carbon mass

Plasma features and alpha particle transport in low-aspect ratio tokamak reactor

International Nuclear Information System (INIS)

Xu Qiang; Wang Shaojie

1997-06-01

The results of the experiment and theory from low-aspect ratio tokamak devices have proved that the MHD stability will be improved. Based on present plasma physics and extrapolation to reduced aspect ratio, the feature of physics of low-aspect ratio tokamak reactor is discussed primarily. Alpha particle confinement and loss in the self-justified low-aspect ratio tokamak reactor parameters and the effect of alpha particle confinement and loss for different aspect ratio are calculated. The results provide a reference for the feasible research of compact tokamak reactor. (9 refs., 2 figs., 3 tabs.)

Correlation of the Na2SiO3 to NaOH Ratios and Solid to Liquid Ratios to the Kedah’s Soil Strength

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Nur Hamzah Hazamaah

2016-01-01

Full Text Available Geopolymer was used for the soil stabilization of Kedah’s soil at different ratios of solid to liquid and Na2SiO3 to NaOH in order to achieve the desired compressive strength. The geopolymerization process which produces an aluminosilicate gel was occurred due to the mixing of Kedah’s soil and fly ash with Na2SiO3 and NaOH. Soil stabilization by geopolymer was synthesized by the activation of fly ash and Kedah’s soil with Na2SiO3 and NaOH at different ratios of solid to liquid (1.5, 2.0, 2.5 and 3.0 and Na2SiO3 to NaOH (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 at a specific constant concentration of NaOH solution of 6M. The compressive strength up to 5.12 MPa was obtained at 3.0 of solid to liquid ratio and 2.5 of Na2SiO3 to NaOH ratio in 7 days curing at room temperature.

Fabrication of high aspect ratio nanocell lattices by ion beam irradiation

International Nuclear Information System (INIS)

Ishikawa, Osamu; Nitta, Noriko; Taniwaki, Masafumi

2016-01-01

Highlights: • Nanocell lattice with a high aspect ratio on InSb semiconductor surface was fabricated by ion beam irradiation. • The fabrication technique consisting of top-down and bottom-up processes was performed in FIB. • High aspect ratio of 2 was achieved in nanocell lattice with a 100 nm interval. • The intermediate-flux irradiation is favorable for fabrication of nanocell with a high aspect ratio. - Abstract: A high aspect ratio nanocell lattice was fabricated on the InSb semiconductor surface using the migration of point defects induced by ion beam irradiation. The fabrication technique consisting of the top-down (formation of voids and holes) and bottom-up (growth of voids and holes into nanocells) processes was performed using a focused ion beam (FIB) system. A cell aspect ratio of 2 (cell height/cell diameter) was achieved for the nanocell lattice with a 100 nm dot interval The intermediate-flux ion irradiation during the bottom-up process was found to be optimal for the fabrication of a high aspect ratio nanocell.

34 CFR 668.172 - Financial ratios.

Science.gov (United States)

2010-07-01

... effect of changes in accounting principles, and the effect of changes in accounting estimates; (2) May... intangible assets defined as intangible in accordance with generally accepted accounting principles; and (5... 34 Education 3 2010-07-01 2010-07-01 false Financial ratios. 668.172 Section 668.172 Education...

Measuring Poisson Ratios at Low Temperatures

Science.gov (United States)

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.

Combining Ratio Estimation for Low Density Parity Check (LDPC) Coding

Science.gov (United States)

Mahmoud, Saad; Hi, Jianjun

2012-01-01

The Low Density Parity Check (LDPC) Code decoding algorithm make use of a scaled receive signal derived from maximizing the log-likelihood ratio of the received signal. The scaling factor (often called the combining ratio) in an AWGN channel is a ratio between signal amplitude and noise variance. Accurately estimating this ratio has shown as much as 0.6 dB decoding performance gain. This presentation briefly describes three methods for estimating the combining ratio: a Pilot-Guided estimation method, a Blind estimation method, and a Simulation-Based Look-Up table. The Pilot Guided Estimation method has shown that the maximum likelihood estimates of signal amplitude is the mean inner product of the received sequence and the known sequence, the attached synchronization marker (ASM) , and signal variance is the difference of the mean of the squared received sequence and the square of the signal amplitude. This method has the advantage of simplicity at the expense of latency since several frames worth of ASMs. The Blind estimation method s maximum likelihood estimator is the average of the product of the received signal with the hyperbolic tangent of the product combining ratio and the received signal. The root of this equation can be determined by an iterative binary search between 0 and 1 after normalizing the received sequence. This method has the benefit of requiring one frame of data to estimate the combining ratio which is good for faster changing channels compared to the previous method, however it is computationally expensive. The final method uses a look-up table based on prior simulated results to determine signal amplitude and noise variance. In this method the received mean signal strength is controlled to a constant soft decision value. The magnitude of the deviation is averaged over a predetermined number of samples. This value is referenced in a look up table to determine the combining ratio that prior simulation associated with the average magnitude of

On the product and ratio of Bessel random variables

Directory of Open Access Journals (Sweden)

Saralees Nadarajah

2005-01-01

Full Text Available The distributions of products and ratios of random variables are of interest in many areas of the sciences. In this paper, the exact distributions of the product |XY| and the ratio |X/Y| are derived when X and Y are independent Bessel function random variables. An application of the results is provided by tabulating the associated percentage points.

MIR hollow waveguide (HWG) isotope ratio analyzer for environmental applications

Science.gov (United States)

Wang, Zhenyou; Zhuang, Yan; Deev, Andrei; Wu, Sheng

2017-05-01

An advanced commercial Mid-InfraRed Isotope Ratio (IR2) analyzer was developed in Arrow Grand Technologies based on hollow waveguide (HWG) as the sample tube. The stable carbon isotope ratio, i.e. δ13C, was obtained by measuring the selected CO2 absorption peaks in the MIR. Combined with a GC and a combustor, it has been successfully employed to measure compound specific δ13C isotope ratios in the field. By using both the 1- pass HWG and 5-path HWG, we are able to measure δ13C isotope ratio at a broad CO2 concentration of 300 ppm-37,500 ppm. Here, we demonstrate its applications in environmental studies. The δ13C isotope ratio and concentration of CO2 exhaled by soil samples was measured in real time with the isotope analyzer. The concentration was found to change with the time. We also convert the Dissolved Inorganic Carbon (DIC) into CO2, and then measure the δ13C isotope ratio with an accuracy of better than 0.3 ‰ (1 σ) with a 6 min test time and 1 ml sample usage. Tap water, NaHCO3 solvent, coca, and even beer were tested. Lastly, the 13C isotope ratio of CO2 exhaled by human beings was obtained <10 seconds after simply blowing the exhaled CO2 into a tube with an accuracy of 0.5‰ (1 σ) without sample preconditioning. In summary, a commercial HWG isotope analyzer was demonstrated to be able to perform environmental and health studies with a high accuracy ( 0.3 ‰/Hz1/2 1 σ), fast sampling rate (up to 10 Hz), low sample consumption ( 1 ml), and broad CO2 concentration range (300 ppm-37,500 ppm).

Tumour alpha/beta ratios and dose-rate selection in brachytherapy

International Nuclear Information System (INIS)

Duchesne, G.M.

2003-01-01

Traditionally brachytherapy employed low dose rate (LDR) techniques. Recent adoption of high dose rate (HDR) applications, addressing radiation protection concerns, has sparked debate over possible reductions in therapeutic ratio. The radiobiological characteristics of two contrasting examples, prostate cancer and cervical cancer, are examined. Both in-vitro and clinical observations of prostate cancer suggest a low α/β ratio. Labelling indices are below 2.5%, translating into long potential doubling times (Tpot ) of 16 to 61 days or more. Clinical PSA doubling times are in the order of years. Analysis of clinical endpoints in prostate cancer treated with either LDR or HDR techniques indicates that its α/β ratio may lie between 1 - 4 Gy, similar to slowly proliferating late reacting tissues. As such, therapeutic gain may arise from the use of hypofractionated HDR treatments, exploiting the sensitivity to large fraction sizes, effectively escalating dose. The slow proliferative rate also gives credence to the use of LDR, although several tumour doublings may occur during the effective treatment time, and analysis of the clinical data using a low α/β ratio suggests that LDR doses are only equivalent to 70 Gy with conventional fractionation. Cervical carcinoma is a rapidly proliferating tumour with Tpot values of 3-6 days. LDR implants were delivered over relatively short treatment times, negating repopulation effects, and the 'hyperfractionation' effect of LDR was suited to the high α/β ratio. HDR, although also preventing significant repopulation, has the potential to decrease the therapeutic ratio if low α/β , late-reacting tissues are not protected. Clinical data however show improved outcomes and reduced morbidity with HDR through reduced doses to normal tissues. Choosing the optimal dose rate in brachytherapy depends on tumour behaviour and achievable accuracy. HDR offers some advantages even for high α/β ratio tumours, and may be the technique of

The CN/C15N isotopic ratio towards dark clouds

Science.gov (United States)

Hily-Blant, P.; Pineau des Forêts, G.; Faure, A.; Le Gal, R.; Padovani, M.

2013-09-01

Understanding the origin of the composition of solar system cosmomaterials is a central question, not only in the cosmochemistry and astrochemistry fields, and requires various approaches to be combined. Measurements of isotopic ratios in cometary materials provide strong constraints on the content of the protosolar nebula. Their relation with the composition of the parental dark clouds is, however, still very elusive. In this paper, we bring new constraints based on the isotopic composition of nitrogen in dark clouds, with the aim of understanding the chemical processes that are responsible for the observed isotopic ratios. We have observed and detected the fundamental rotational transition of C15N towards two starless dark clouds, L1544 and L1498. We were able to derive the column density ratio of C15N over 13CN towards the same clouds and obtain the CN/C15N isotopic ratios, which were found to be 500 ± 75 for both L1544 and L1498. These values are therefore marginally consistent with the protosolar value of 441. Moreover, this ratio is larger than the isotopic ratio of nitrogen measured in HCN. In addition, we present model calculations of the chemical fractionation of nitrogen in dark clouds, which make it possible to understand how CN can be deprived of 15N and HCN can simultaneously be enriched in heavy nitrogen. The non-fractionation of N2H+, however, remains an open issue, and we propose some chemical way of alleviating the discrepancy between model predictions and the observed ratios. Appendices are available in electronic form at http://www.aanda.orgThe reduced spectra (in FITS format) are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/557/A65

Rotating spacetimes with asymptotic nonflat structure and the gyromagnetic ratio

International Nuclear Information System (INIS)

Aliev, Alikram N.

2008-01-01

In general relativity, the gyromagnetic ratio for all stationary, axisymmetric, and asymptotically flat Einstein-Maxwell fields is known to be g=2. In this paper, we continue our previous works of examination of this result for rotating charged spacetimes with asymptotic nonflat structure. We first consider two instructive examples of these spacetimes: The spacetime of a Kerr-Newman black hole with a straight cosmic string on its axis of symmetry and the Kerr-Newman Taub-NUT (Newman-Unti-Tamburino) spacetime. We show that for both spacetimes the gyromagnetic ratio g=2 independent of their asymptotic structure. We also extend this result to a general class of metrics which admit separation of variables for the Hamilton-Jacobi and wave equations. We proceed with the study of the gyromagnetic ratio in higher dimensions by considering the general solution for rotating charged black holes in minimal five-dimensional gauged supergravity. We obtain the analytic expressions for two distinct gyromagnetic ratios of these black holes that are associated with their two independent rotation parameters. These expressions reveal the dependence of the gyromagnetic ratio on both the curvature radius of the AdS background and the parameters of the black holes: The mass, electric charge, and two rotation parameters. We explore some special cases of interest and show that when the two rotation parameters are equal to each other and the rotation occurs at the maximum angular velocity, the gyromagnetic ratio g=4 regardless of the value of the electric charge. This agrees precisely with our earlier result obtained for general Kerr-AdS black holes with a test electric charge. We also show that in the Bogomol'nyi-Prasad-Sommerfield (BPS) limit the gyromagnetic ratio for a supersymmetric black hole with equal rotation parameters ranges between 2 and 4

Digit ratio predicts sense of direction in women.

Directory of Open Access Journals (Sweden)

Xiaoqian J Chai

Full Text Available The relative length of the second-to-fourth digits (2D:4D has been linked with prenatal androgen in humans. The 2D:4D is sexually dimorphic, with lower values in males than females, and appears to correlate with diverse measures of behavior. However, the relationship between digit ratio and cognition, and spatial cognition in particular, has produced mixed results. In the present study, we hypothesized that spatial tasks separating cue conditions that either favored female or male strategies would examine this structure-function correlation with greater precision. Previous work suggests that males are better in the use of directional cues than females. In the present study, participants learned a target location in a virtual landscape environment, in conditions that contained either all directional (i.e., distant or compass bearing cues, or all positional (i.e., local, small objects cues. After a short delay, participants navigated back to the target location from a novel starting location. Males had higher accuracy in initial search direction than females in environments with all directional cues. Lower digit ratio was correlated with higher accuracy of initial search direction in females in environments with all directional cues. Mental rotation scores did not correlate with digit ratio in either males or females. These results demonstrate for the first time that a sex difference in the use of directional cues, i.e., the sense of direction, is associated with more male-like digit ratio.

Digit ratio predicts sense of direction in women.

Science.gov (United States)

Chai, Xiaoqian J; Jacobs, Lucia F

2012-01-01

The relative length of the second-to-fourth digits (2D:4D) has been linked with prenatal androgen in humans. The 2D:4D is sexually dimorphic, with lower values in males than females, and appears to correlate with diverse measures of behavior. However, the relationship between digit ratio and cognition, and spatial cognition in particular, has produced mixed results. In the present study, we hypothesized that spatial tasks separating cue conditions that either favored female or male strategies would examine this structure-function correlation with greater precision. Previous work suggests that males are better in the use of directional cues than females. In the present study, participants learned a target location in a virtual landscape environment, in conditions that contained either all directional (i.e., distant or compass bearing) cues, or all positional (i.e., local, small objects) cues. After a short delay, participants navigated back to the target location from a novel starting location. Males had higher accuracy in initial search direction than females in environments with all directional cues. Lower digit ratio was correlated with higher accuracy of initial search direction in females in environments with all directional cues. Mental rotation scores did not correlate with digit ratio in either males or females. These results demonstrate for the first time that a sex difference in the use of directional cues, i.e., the sense of direction, is associated with more male-like digit ratio.

A Hybrid Joint Moment Ratio Test for Financial Time Series

NARCIS (Netherlands)

Groenendijk, Patrick A.; Lucas, André; Vries, de Casper G.

1998-01-01

We advocate the use of absolute moment ratio statistics in conjunctionwith standard variance ratio statistics in order to disentangle lineardependence, non-linear dependence, and leptokurtosis in financial timeseries. Both statistics are computed for multiple return horizonssimultaneously, and the

Sex ratio in two species of Pegoscapus wasps (Hymenoptera: Agaonidae) that develop in figs: can wasps do mathematics, or play sex ratio games?

Science.gov (United States)

Ramírez-Benavides, William; Monge-Nájera, Julián; Chavarría, Juan B

2009-09-01

The fig pollinating wasps (Hymenoptera: Agaonidae) have obligate arrhenotoky and a breeding structure that fits local mate competition (LMC). It has been traditionally assumed that LMC organisms adjust the sex ratio by laying a greater proportion of male eggs when there is superparasitism (several foundresses in a host). We tested the assumption with two wasp species, Pegoscapus silvestrii, pollinator of Ficus pertusa and Pegoscapus tonduzi, pollinator of Ficus eximia (= F citrifolia), in the Central Valley of Costa Rica. Total number of wasps and seeds were recorded in individual isolated naturally colonized syconia. There was a constant additive effect between the number of foundresses and the number of males produced in the brood of a syconium, while the number of females decreased. Both wasp species seem to have precise sex ratios and probably lay the male eggs first in the sequence, independently of superparasitism and clutch size: consequently, they have a non-random sex allocation. Each syconium of Ficus pertusa and of F. eximia colonized by one foundress had similar mean numbers of females, males, and seeds. The two species of wasps studied do not seem to adjust the sex ratio when there is superparasitism. Pollinating fig wasp behavior is better explained by those models not assuming that females do mathematical calculations according to other females' sex ratios, size, number of foundresses, genetic constitution, clutch size or environmental conditions inside the syconium. Our results are in agreement with the constant male number hypothesis, not with sex ratio games.

Are elderly dependency ratios associated with general population suicide rates?

Science.gov (United States)

Shah, Ajit

2011-05-01

The elderly population size is increasing worldwide due to falling birth rates and increasing life expectancy. It has been hypothesized that as the elderly dependency ratio (the ratio of those over the age of 65 years to those under 65) increases, there will be fewer younger people available to care for older people and this, in turn, will increase the burden on younger carers with increased levels of psychiatric morbidity leading to an increase in general population suicide rates. A cross-national study examining the relationship between elderly dependency ratios and general population suicide rates was conducted using data from the World Health Organization and the United Nations websites. The main findings were of a significant and independent positive correlation between elderly dependency ratios and general population suicide rates in both genders. The contribution of cross-national differences in psychiatric morbidity in younger carers on general population suicide rates requires further study. The prevalence of psychiatric morbidity in younger carers of older people should be examined by: (i) cross-national studies using standardized measures of psychiatric morbidity that are education-free, culture-fair and language-fair; and (ii) within-country longitudinal studies with changing elderly dependency ratios over time.

Vapor-melt Ratio in Laser Fine Cutting of Slot Arrays

International Nuclear Information System (INIS)

Wang Xuyue; Meng Qingxuan; Kang Renke; Xu Wenji; Guo Dongming; Wang Lianji

2011-01-01

In order to improve cut quality for slot arrays, a new method of laser fine cutting under the consideration of the ratio of vapor to melt is presented. Laser cutting of 6063 aluminum alloy sheet, 0.5 mm in thickness, was carried out on a JK701H Nd:YAG pulse laser cutting system. The effects of vapor-melt ratio on kerf width, surface roughness and recast layer were studied which relate cutting qualities. Observation on the cut samples with different vapor-melt ratios (0.687, 1.574, 3.601 varied with laser power increasing, and 1.535, 3.601, 7.661 with decreasing of beam cutting speed) shows that high vapor-melt ratio improves laser cut quality clearly. Kerf width 0.2 mm of smooth area on kerf top area and thickness 2.03 μm of recast layer are obtained. No dross was found on the kerf bottom and the percentage of the smooth area is up to 40% out of whole kerf side. The research on vapor-melt ratio provides a deeper understanding of laser cutting and improves laser cut quality effectively.

Measurement of the atmospheric muon charge ratio with the OPERA detector

CERN Document Server

Agafonova, N.; Aoki, S.; Ariga, A.; Ariga, T.; Autiero, D.; Badertscher, A.; Bagulya, A.; Bertolin, A.; Besnier, M.; Bick, D.; Boyarkin, V.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Cozzi, M.; D'Amato, G.; Dal Corso, F.; D'Ambrosio, N.; De Lellis, G.; Declais, Y.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Dmitrievski, S.; Dracos, M.; Duchesneau, D.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, A.; Esposito, L.S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Frekers, D.; Fukuda, T.; Fukushima, C.; Galkin, V.I.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Goldberg, J.; Golubkov, D.; Goncharova, L.; Gornushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gustavino, C.; Hagner, C.; Hamada, K.; Hara, T.; Hierholzer, M.; Hoshino, K.; Ieva, M.; Jakovcic, K.; Jollet, C.; Juget, F.; Kazuyama, M.; Kim, S.H.; Kimura, M.; Klicek, B.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Kubota, H.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, A.; Lutter, G.; Malgin, A.; Mandrioli, G.; Marotta, A.; Marteau, J.; Matsuo, T.; Matveev, V.; Mauri, N.; Medinaceli, E.; Meisel, F.; Meregaglia, A.; Migliozzi, P.; Mikado, S.; Miyamoto, S.; Monacelli, P.; Morishima, K.; Moser, U.; Muciaccia, M.T.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakano, T.; Naumov, D.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Olchevski, A.; Oldorf, C.; Orlova, G.; Osedlo, V.; Paniccia, M.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pilipenko, V.; Pistillo, C.; Policastro, G.; Polukhina, N.; Pozzato, M.; Pretzl, K.; Publichenko, P.; Pupilli, F.; Rescigno, R.; Roganova, T.; Rokujo, H.; Romano, G.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryasny, V.; Ryazhskaya, O.; Sato, O.; Sato, Y.; Schembri, A.; Schmidt Parzefall, W.; Schroeder, H.; Scotto Lavina, L.; Sheshukov, A.; Shibuya, H.; Simone, S.; Sioli, M.; Sirignano, C.; Sirri, G.; Song, J.S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, P.; Takahashi, S.; Tenti, M.; Terranova, F.; Tezuka, I.; Tioukov, V.; Tolun, P.; Tran, T.; Tufanli, S.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J.L.; Wilquet, G.; Wonsak, B.; Yakushev, V.; Yoon, C.S.; Yoshioka, T.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, A.; Zimmermann, R.

2010-01-01

The OPERA detector at the Gran Sasso underground laboratory (LNGS) was used to measure the atmospheric muon charge ratio in the TeV energy region. We analyzed 403069 atmospheric muons corresponding to 113.4 days of livetime during the 2008 CNGS run. We computed separately the muon charge ratio for single and for multiple muon events in order to select different energy regions of the primary cosmic ray spectrum and to test the charge ratio dependence on the primary composition. The measured charge ratio values were corrected taking into account the charge-misidentification errors. Data have also been grouped in five bins of the "vertical surface energy". A fit to a simplified model of muon production in the atmosphere allowed the determination of the pion and kaon charge ratios weighted by the cosmic ray energy spectrum.

PENGARUH RASIO KEUANGAN DAN PERUBAHAN PAJAK DIVIDEN TERHADAP DIVIDEND PAYOUT RATIO PERUSAHAAN TERBUKA

Directory of Open Access Journals (Sweden)

Cahyo Dwi Sulistiyo

2016-05-01

Full Text Available Abstract The objective of this research was to analyse influence company performance ratio such as ROA, DER, Size,EPS, Current Ratio, Growth and changes in dividend tax rates to Dividend Payout Ratio. The variables testedusing panel regression analysis. Research conducted on 40 emitens included in LQ 45 index of Indonesia StockExchange (ISE with years of research covering 2006 to 2012. The panel regression results show that  thevariables ROA, Current Ratio, Size, andGrowth showed a significant effect on dividend payout ratio,while thevariable DER, EPS, and Tax have no significant effect on the dividend payout ratio but all the variablesimultaneously influential to dividend payout ratio.

Mortality, fertility, and the OY ratio in a model hunter-gatherer system.

Science.gov (United States)

White, Andrew A

2014-06-01

An agent-based model (ABM) is used to explore how the ratio of old to young adults (the OY ratio) in a sample of dead individuals is related to aspects of mortality, fertility, and longevity experienced by the living population from which the sample was drawn. The ABM features representations of rules, behaviors, and constraints that affect person- and household-level decisions about marriage, reproduction, and infant mortality in hunter-gatherer systems. The demographic characteristics of the larger model system emerge through human-level interactions playing out in the context of "global" parameters that can be adjusted to produce a range of mortality and fertility conditions. Model data show a relationship between the OY ratios of living populations (the living OY ratio) and assemblages of dead individuals drawn from those populations (the dead OY ratio) that is consistent with that from empirically known ethnographic hunter-gatherer cases. The dead OY ratio is clearly related to the mean ages, mean adult mortality rates, and mean total fertility rates experienced by living populations in the model. Sample size exerts a strong effect on the accuracy with which the calculated dead OY ratio reflects the actual dead OY ratio of the complete assemblage. These results demonstrate that the dead OY ratio is a potentially useful metric for paleodemographic analysis of changes in mortality and mean age, and suggest that, in general, hunter-gatherer populations with higher mortality, higher fertility, and lower mean ages are characterized by lower dead OY ratios. Copyright © 2014 Wiley Periodicals, Inc.

THE EFFECTS OF INCREASE THE COMPRESSION RATIO ON PERFORMANCE OF A DIESEL ENGINE

Directory of Open Access Journals (Sweden)

Adnan PARLAK

2003-02-01

Full Text Available An optimisation of the Diesel cycle has been performed for power output and thermal efficiency with respect to compression ratio for various extreme temperature ratio. The relation between compression ratio and extreme temperature ratio, which gives optimum performance is derived. As the compression ratio of the diesel engine is increased in comparison to the optimum value of the engine, it is shown that the performance of the engine is decreased. The experimental study agrees with these results. In this study, compression ratio of a single cylinder pre-combustion chamber variable compression ratio Ricardo E6 type engine with the optimum compression ratio of 18.20 was increased to 19.60. As a results of this increase, specific fuel consumption was increased about 8 % and brake thermal efficiency was decreased about 7.5 %.

Computer-controlled detection system for high-precision isotope ratio measurements

International Nuclear Information System (INIS)

McCord, B.R.; Taylor, J.W.

1986-01-01

In this paper the authors describe a detection system for high-precision isotope ratio measurements. In this new system, the requirement for a ratioing digital voltmeter has been eliminated, and a standard digital voltmeter interfaced to a computer is employed. Instead of measuring the ratio of the two steadily increasing output voltages simultaneously, the digital voltmeter alternately samples the outputs at a precise rate over a certain period of time. The data are sent to the computer which calculates the rate of charge of each amplifier and divides the two rates to obtain the isotopic ratio. These results simulate a coincident measurement of the output of both integrators. The charge rate is calculated by using a linear regression method, and the standard error of the slope gives a measure of the stability of the system at the time the measurement was taken

Planned Enhanced Wakefield Transformer Ratio Experiment at Argonne Wakefield Accelerator

CERN Document Server

Kanareykin, Alex; Gai, Wei; Jing, Chunguang; Konecny, Richard; Power, John G

2005-01-01

In this paper, we present a preliminary experimental study of a wakefield accelerating scheme that uses a carefully spaced and current ramped electron pulse train to produce wakefields that increases the transformer ratio much higher than 2. A dielectric structure was designed and fabricated to operate at 13.625 GHz with dielectric constant of 15.7. The structure will be initially excited by two beams with first and second beam charge ratio of 1:3. The expected transformer ratio is 3 and the setup can be easily extend to 4 pulses which leads to a transformer ratio of more than 6. The dielectric structure cold test results show the tube is within the specification. A set of laser splitters was also tested to produce ramped bunch train of 2 - 4 pulses. Overall design of the experiment and initial results will be presented.

Ratio-based vs. model-based methods to correct for urinary creatinine concentrations.

Science.gov (United States)

Jain, Ram B

2016-08-01

Creatinine-corrected urinary analyte concentration is usually computed as the ratio of the observed level of analyte concentration divided by the observed level of the urinary creatinine concentration (UCR). This ratio-based method is flawed since it implicitly assumes that hydration is the only factor that affects urinary creatinine concentrations. On the contrary, it has been shown in the literature, that age, gender, race/ethnicity, and other factors also affect UCR. Consequently, an optimal method to correct for UCR should correct for hydration as well as other factors like age, gender, and race/ethnicity that affect UCR. Model-based creatinine correction in which observed UCRs are used as an independent variable in regression models has been proposed. This study was conducted to evaluate the performance of ratio-based and model-based creatinine correction methods when the effects of gender, age, and race/ethnicity are evaluated one factor at a time for selected urinary analytes and metabolites. It was observed that ratio-based method leads to statistically significant pairwise differences, for example, between males and females or between non-Hispanic whites (NHW) and non-Hispanic blacks (NHB), more often than the model-based method. However, depending upon the analyte of interest, the reverse is also possible. The estimated ratios of geometric means (GM), for example, male to female or NHW to NHB, were also compared for the two methods. When estimated UCRs were higher for the group (for example, males) in the numerator of this ratio, these ratios were higher for the model-based method, for example, male to female ratio of GMs. When estimated UCR were lower for the group (for example, NHW) in the numerator of this ratio, these ratios were higher for the ratio-based method, for example, NHW to NHB ratio of GMs. Model-based method is the method of choice if all factors that affect UCR are to be accounted for.

Inference for the Sharpe Ratio Using a Likelihood-Based Approach

Directory of Open Access Journals (Sweden)

Ying Liu

2012-01-01

Full Text Available The Sharpe ratio is the prominent risk-adjusted performance measure used by practitioners. Statistical testing of this ratio using its asymptotic distribution has lagged behind its use. In this paper, highly accurate likelihood analysis is applied for inference on the Sharpe ratio. Both the one- and two-sample problems are considered. The methodology has O(n−3/2 distributional accuracy and can be implemented using any parametric return distribution structure. Simulations are provided to demonstrate the method's superior accuracy over existing methods used for testing in the literature.

An improved data acquisition system for isotopic ratio mass spectrometers

International Nuclear Information System (INIS)

Saha, T.K.; Reddy, B.; Nazare, C.K.; Handu, V.K.

1999-01-01

Isotopic ratio mass spectrometers designed and fabricated to measure the isotopic ratios with a precision of better than 0.05%. In order to achieve this precision, the measurement system consisting of ion signal to voltage converters, analog to digital converters, and data acquisition electronics should be at least one order better than the overall precision of measurement. Using state of the art components and techniques, a data acquisition system, which is an improved version of the earlier system, has been designed and developed for use with multi-collector isotopic ratio mass spectrometers

Stability of high β large aspect ratio tokamaks

International Nuclear Information System (INIS)

Cowley, S.C.

1991-10-01

High β(β much-gt ε/q 2 ) large aspect ratio (ε much-gt 1) tokamak equilibria are shown to be always stable to ideal M.H.D. modes that are localized about a flux surface. Both the ballooning and interchange modes are shown to be stable. This work uses the analytic high β large aspect ratio tokamak equilibria developed by Cowley et.al., which are valid for arbitrary pressure and safety factor profiles. The stability results make no assumption about these profiles or the shape of the boundary. 14 refs., 4 figs

Carbon isotope ratios in field Population II giant stars

International Nuclear Information System (INIS)

Sneden, C.; Pilachowski, C.A.; Vandenberg, D.A.; Kitt Peak National Observatory, Tucson, AZ; Victoria Univ., Canada)

1986-01-01

Carbon isotope ratios have been derived from high-resolution spectra of the CH G-band in 15 very metal-poor Population II giant stars and two similar dwarf stars. Many of the giants possess very low C-12/C-13 ratios, some approaching the CN cycle equilibrium value. The metal-poor dwarfs do not have detectable CH-13 features; thus the low carbon isotope ratios in the giants probably are due to their internal evolutions. These results strongly support the idea that at least part of the anomalously low C/N values in Population II giants arises from very efficient mixing of their envelopes into the CN cycle burning layers. Detailed calculations of the expected CNO surface abundances in Population II giants in different evolutionary states have been performed. These computations demonstrate that the observed carbon isotope ratios cannot be produced during the first dredge-up mixing phases in low-mass, low metal abundance stars. Numerical experiments show that theoretical and observational results can be brought into agreement with artificially induced extra mixing. An agent to provoke this additional mixing has not been identified with certainty yet, although internal stellar rotation is a promising candidate. 63 references

Fetal omphalocele ratios predict outcomes in prenatally diagnosed omphalocele.

Science.gov (United States)

Montero, Freddy J; Simpson, Lynn L; Brady, Paula C; Miller, Russell S

2011-09-01

The objective of the study was to evaluate whether ratios considering omphalocele diameter relative to fetal biometric measurements perform better than giant omphalocele designation at predicting inability to achieve neonatal primary surgical closure. Cases of fetal omphalocele that underwent evaluation between May 2003 and July 2010 were identified. Inclusion was restricted to live births with plan for postnatal repair. Omphalocele diameter upon antenatal ultrasound was compared with abdominal circumference, femur length, and head circumference, yielding the respective omphalocele (O)/abdominal circumference (AC), O/femur length (FL), and O/head circumference (HC) ratios. The absolute measurements were used to classify giant lesions. Omphalocele ratios and giant omphalocele designations were evaluated as predictors of inability to achieve primary repair. Among 25 included cases, staged or delayed closure occurred in 52%. With an optimal cutoff of 0.21 or greater, O/HC best predicted the primary outcome (sensitivity, 84.6%; specificity, 58.3%; odds ratio, 7.7). The O/HC of 0.21 or greater outperformed giant designations. The O/HC of 0.21 or greater best predicted staged or delayed omphalocele closure. Giant omphalocele designation, regardless of definition, poorly predicted outcome. Copyright © 2011 Mosby, Inc. All rights reserved.

Abundance Ratios in Dwarf Elliptical Galaxies

NARCIS (Netherlands)

Sen, Seyda; Peletier, Reynier F.; Toloba, Elisa; Mentz, Jaco J.

The aim of this study is to determine abundance ratios and star formation histories (SFH) of dwarf ellipticals in the nearby Virgo cluster. We perform a stellar population analysis of 39 dEs and study them using index-index and scaling relations. We find an unusual behaviour where [Na/Fe] is

A Hybrid Joint Moment Ratio Test for Financial Time Series

NARCIS (Netherlands)

P.A. Groenendijk (Patrick); A. Lucas (André); C.G. de Vries (Casper)

1998-01-01

textabstractWe advocate the use of absolute moment ratio statistics in conjunction with standard variance ratio statistics in order to disentangle linear dependence, non-linear dependence, and leptokurtosis in financial time series. Both statistics are computed for multiple return horizons

An evaluation of the usefulness of cash flow ratios to predict financial distress

Directory of Open Access Journals (Sweden)

L. Jooste

2007-12-01

Full Text Available Purpose: With the introduction of the cash flow statement it became an integral part of financial reporting. A need arose to develop ratios for the effective evaluation of cash flow information. This article investigates cash flow ratios suggested by various researchers and suggests a list of ratios with the potential to predict financial failure. Design: The cash flow ratios suggested by researchers, from as early as 1966, are investigated and eight cash flow ratios selected for inclusion in an analysis to predict financial failure. Ten failed entities are selected for a cash flow evaluation by means of the selected ratios for five years prior to failure. For a comparison, non-failed entities in similar sectors are selected and also evaluated by means of the cash flow ratios. The mean values of each ratio, for each year prior to failure, were then calculated and the means of the failed entities were compared to the non-failed entities. Findings: The comparison revealed that cash flow ratios have predictive value with the cash flow to total debt identified as the best indicator of failure. It was also determined that, although failed entities have lower cash flows than non-failed entities, they also had smaller reserves of liquid assets. Furthermore, they have less capacity to meet debt obligations and they tend to incur more debt. The ratios of the failed entities were unstable and fluctuated from one year to the next. Finally, bankruptcy could be predicted three years prior to financial failure. Implications: Income statement and balance sheet ratios are not enough to measure liquidity. An entity can have positive liquidity ratios and increasing profits, yet have serious cash flow problems. Ratios developed from the cash flow statement should supplement traditional accrual-based ratios to provide additional information on the financial strengths and weaknesses of an entity .

A heritable component in sex ratio and caste determination in a Cardiocondyla ant

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Heinze Jürgen

2009-10-01

Full Text Available Abstract Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias" - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids. Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals. Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals even when uniformly nursed by workers from another colony. Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

A heritable component in sex ratio and caste determination in a Cardiocondyla ant.

Science.gov (United States)

Frohschammer, Sabine; Heinze, Jürgen

2009-10-28

Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias") - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids.Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals). Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals) even when uniformly nursed by workers from another colony.Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

LITERATURE SURVEY ON ISOTOPIC ABUNDANCE RATIO MEASUREMENTS - 2001-2005

International Nuclear Information System (INIS)

HOLDEN, N.E.

2005-01-01

Along with my usual weekly review of the published literature for new nuclear data, I also search for new candidates for best measurements of isotopic abundances from a single source. Most of the published articles, that I previously had found in the Research Library at the Brookhaven Lab, have already been sent to the members of the Atomic Weights Commission, by either Michael Berglund or Thomas Walczyk. In the last few days, I checked the published literature for any other articles in the areas of natural variations in isotopic abundance ratios, measurements of isotopic abundance ratios on samples of extra-terrestrial material and isotopic abundance ratio measurements performed using ICPMS instruments. Hopefully this information will be of interest to members of the Commission, the sub-committee on isotopic abundance measurements (SIAM), members of the former sub-committee on natural isotopic fractionation (SNIF), the sub-committee on extra-terrestrial isotope ratios (SETIR), the RTCE Task Group and the Guidelines Task Group, who are dealing with ICPMS and TIMS comparisons. In the following report, I categorize the publications in one of four areas. Measurements performed using either positive or negative ions with Thermal Ionization Mass Spectrometer, TIMS, instruments; measurements performed on Inductively Coupled Plasma Mass Spectrometer, ICPMS, instruments; measurements of natural variations of the isotopic abundance ratios; and finally measurements on extra-terrestrial samples with instrumentation of either type. There is overlap in these areas. I selected out variations and ET results first and then categorized the rest of the papers by TIMS and ICPMS

Systems Biology and Ratio-Based, Real-Time Disease Surveillance.

Science.gov (United States)

Fair, J M; Rivas, A L

2015-08-01

Most infectious disease surveillance methods are not well fit for early detection. To address such limitation, here we evaluated a ratio- and Systems Biology-based method that does not require prior knowledge on the identity of an infective agent. Using a reference group of birds experimentally infected with West Nile virus (WNV) and a problem group of unknown health status (except that they were WNV-negative and displayed inflammation), both groups were followed over 22 days and tested with a system that analyses blood leucocyte ratios. To test the ability of the method to discriminate small data sets, both the reference group (n = 5) and the problem group (n = 4) were small. The questions of interest were as follows: (i) whether individuals presenting inflammation (disease-positive or D+) can be distinguished from non-inflamed (disease-negative or D-) birds, (ii) whether two or more D+ stages can be detected and (iii) whether sample size influences detection. Within the problem group, the ratio-based method distinguished the following: (i) three (one D- and two D+) data classes; (ii) two (early and late) inflammatory stages; (iii) fast versus regular or slow responders; and (iv) individuals that recovered from those that remained inflamed. Because ratios differed in larger magnitudes (up to 48 times larger) than percentages, it is suggested that data patterns are likely to be recognized when disease surveillance methods are designed to measure inflammation and utilize ratios. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Effect of Gynosaponin on Rumen Methanogenesis under Different Forage-Concentrate Ratios

Directory of Open Access Journals (Sweden)

Bakhetgul Manatbay

2014-08-01

Full Text Available The study aimed to investigate the effects of gynosaponin on in vitro methanogenesis under different forage-concentrate ratios (F:C ratios. Experiment was conducted with two kinds of F:C ratios (F:C = 7:3 and F:C = 3:7 and gynosaponin addition (0 mg and 16 mg in a 2×2 double factorial design. In the presence of gynosaponin, methane production and acetate concentration were significantly decreased, whereas concentration of propionate tended to be increased resulting in a significant reduction (p<0.05 of acetate:propionate ratio (A:P ratio, in high-forage substrate. Gynosaponin treatment increased (p<0.05 the butyrate concentration in both F:C ratios. Denaturing gradient gel electrophoresis (DGGE analysis showed there was no apparent shift in the composition of total bacteria, protozoa and methanogens after treated by gynosaponin under both F:C ratios. The real-time polymerase chain reaction (PCR analysis indicated that variable F:C ratios significantly affected the abundances of Fibrobacter succinogenes, Rumninococcus flavefaciens, total fungi and counts of protozoa (p<0.05, but did not affect the mcrA gene copies of methanogens and abundance of total bacteria. Counts of protozoa and abundance of F.succinogenes were decreased significantly (p<0.05, whereas mcrA gene copies of methanogens were decreased slightly (p<0.10 in high-forage substrate after treated by gynosaponin. However, gynosaponin treatment under high-concentrate level did not affect the methanogenesis, fermentation characteristics and tested microbes. Accordingly, overall results suggested that gynosaponin supplementation reduced the in vitro methanogenesis and improved rumen fermentation under high-forage condition by changing the abundances of related rumen microbes.

Design studies of low-aspect ratio quasi-omnigenous stellarators

International Nuclear Information System (INIS)

Spong, D.A.; Hirshman, S.; Whitson, J.C.

2001-01-01

Significant progress has been made in the development of new modest-size compact stellarator devices that could test optimization principles for the design of a more attractive reactor. These are 3 and 4 field period low-aspect-ratio quasi-omnigenous (QO) stellarators based on an optimization method that targets improved confinement, stability, ease of coil design, low-aspect-ratio, and low bootstrap current. (author)

Ratio asymptotics of Hermite-Pade polynomials for Nikishin systems

International Nuclear Information System (INIS)

Aptekarev, A I; Lopez, Guillermo L; Rocha, I A

2005-01-01

The existence of ratio asymptotics is proved for a sequence of multiple orthogonal polynomials with orthogonality relations distributed among a system of m finite Borel measures with support on a bounded interval of the real line which form a so-called Nikishin system. For m=1 this result reduces to Rakhmanov's celebrated theorem on the ratio asymptotics for orthogonal polynomials on the real line.

Prediction of renovascualar hypertension by captopril-stimulated renal vein renin ratios

International Nuclear Information System (INIS)

Roubidoux, M.A.; Dunnick, N.R.; Svetkey, L.; Newmann, G.E.; Cohan, R.H.; Kadir, S.; Klotman, P.

1989-01-01

The authors have prospectively studied 114 patients with suspected renovascular hypertension to determine whether captopril-stimulated, selective, renal vein renin ratios could be used to predict renovascular hypertension. As judged by the response to correction of renal artery lesions, 14 patients had renovascular hypertension, and renal vein renin ratios were significant in eight (sensitivity 57%). Overall, the positive predictive value of renal vein renin ratios was 33%, and the negative predictive value was 89%. The authors concluded that, in patients with renal artery stenosis, renal vein renin ratios predict neither the need for conventional arteriography nor potential benefit from the correction of vascular insufficiency

Cell pairing ratio controlled micro-environment with valve-less electrolytic isolation

KAUST Repository

Chen, Yu-Chih

2012-01-01

We present a ratio controlled cell-to-cell interaction chip using valve-less isolation. We incorporated electrolysis in a microfluidic channel. In each microfluidic chamber, we loaded two types of different cells at various pairing ratios. More than 80% of the microchambers were successfully loaded with a specific target pairing ratio. For the proof of concept, we have demonstrated the cell-to-cell interaction between prostate cancer cells and muscle stem cells can be controlled by cell pairing ratios through growth factor secretion. The experimental data shows that sealing of microenvironment by air generated from electrolysis does not affect cell viability and cell interaction assay results. © 2012 IEEE.

Breeding sex ratio and population size of loggerhead turtles from Southwestern Florida.

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Jacob A Lasala

Full Text Available Species that display temperature-dependent sex determination are at risk as a result of increasing global temperatures. For marine turtles, high incubation temperatures can skew sex ratios towards females. There are concerns that temperature increases may result in highly female-biased offspring sex ratios, which would drive a future sex ratio skew. Studying the sex ratios of adults in the ocean is logistically very difficult because individuals are widely distributed and males are inaccessible because they remain in the ocean. Breeding sex ratios (BSR are sought as a functional alternative to study adult sex ratios. One way to examine BSR is to determine the number of males that contribute to nests. Our goal was to evaluate the BSR for loggerhead turtles (Caretta caretta nesting along the eastern Gulf of Mexico in Florida, from 2013-2015, encompassing three nesting seasons. We genotyped 64 nesting females (approximately 28% of all turtles nesting at that time and up to 20 hatchlings from their nests (n = 989 using 7 polymorphic microsatellite markers. We identified multiple paternal contributions in 70% of the nests analyzed and 126 individual males. The breeding sex ratio was approximately 1 female for every 2.5 males. We did not find repeat males in any of our nests. The sex ratio and lack of repeating males was surprising because of female-biased primary sex ratios. We hypothesize that females mate offshore of their nesting beaches as well as en route. We recommend further comparisons of subsequent nesting events and of other beaches as it is imperative to establish baseline breeding sex ratios to understand how growing populations behave before extreme environmental effects are evident.

Mean platelet volume, neutrophil to lyphocyte ratio and platelet to lymphocyte ratio in psoriasis

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Mehmet Ünal

2015-06-01

Full Text Available Background and Design: It has been demonstrated that ratio of neutrophil and platelet count systemic inflammation and is associated with prognosis of many cardiovascular diseases, malignates and chronic inflammatory diseases.As far as it is known, there are no studies investigating neutrophil/lymphocyeratio(NLR, platelet/lymphocyte ratio(PLR and mean platelet volume(MPV values together within the context of psoriasis, a chronic and systemic inflammatory disease. Materials and Methods: 320 patients followed up in our polyclinic with psoriasis vulgaris and 200 healthy persons were evaluated in the study. Results: Leukocyte, neutrophil, platelet, MPV, NLR and PLR values in patients with psoriasis were significantly higher, and lymphocyte count, on the other hand, was significantly lower than those of the control group. No significant difference was found between MPV, NLR and PLR values of patients with or without a family history, nail and joint involvement. Conclusions: These parameters may be made use of as cheap and easily applicable methods in predicting which psoriasis patients are under the risk of cardiovascular disease. PLR is a better inflammation marker than MPV and NLR in patients with psoriasis. We did not observe a significant relationship between MPV, NLR and PLR values and such disease characteristics as severity of disease, joint involvement, nail involvement and duration of disease in patients with psoriasis. So, we believe that there is little information on the extent to which MPV,NLR and PLR might be useful regarding these characteristics.

High aspect ratio spheromak experiments

International Nuclear Information System (INIS)

Robertson, S.; Schmid, P.

1987-05-01

The Reversatron RFP (R/a = 50cm/8cm) has been operated as an ohmically heated spheromak of high aspect ratio. We find that the dynamo can drive the toroidal field upward at rates as high as 10 6 G/sec. Discharges can be initiated and ramped upward from seed fields as low as 50 G. Small toroidal bias fields of either polarity (-0.2 < F < 0.2) do not significantly affect operation. 5 refs., 3 figs

Correlation between supercooled liquid relaxation and glass poisson’s ratio

DEFF Research Database (Denmark)

Sun, Q.J.; Hu, L.N.; Zhou, C.

2015-01-01

in the ratio r and this relation can be described by the empirical function v = 0.5 − A ∗ exp(−B ∗ r), where A and B are constants. This correlation might imply that glass plasticity is associated with the competition between the α and the slow β relaxations in SLs. The underlying physics of this correlation......We report on a correlation between the supercooled liquid (SL) relaxation and glass Poisson’s ratio (v) by comparing the activation energy ratio (r) of the α and the slow β relaxations and the v values for both metallic and nonmetallic glasses. Poisson’s ratio v generally increases with an increase...... lies in the heredity of the structural heterogeneity from liquid to glass. This work gives insights into both the microscopic mechanism of glass deformation through the SL dynamics and the complex structural evolution during liquid-glass transition....

Magnetic Resonance Signal Intensity Ratio Measurement Before Uterine Artery Embolization

DEFF Research Database (Denmark)

Duvnjak, Stevo; Ravn, Pernille; Green, Anders

2017-01-01

, 52 patients were included in this prospective study. The SI ratio before UFE was calculated using circular region of interests placed on the dominant fibroid and the iliac muscle. The SI fibroid-to-iliac muscle ratio was calculated as SI of the dominant fibroid/SI of the iliac muscle on T1-, T2......-, and T1 post-contrast-weighted sequences. The dominant fibroid volume was measured and analyzed before and after UFE. RESULTS: In all, 46 patients who completed the three-month follow-up MRI were available for analysis. The correlation between SI fibroid-to-muscle ratio at the T2-weighted sequence...... positive correlation (r = 0.439, p T2-weighted sequence. The area under curve (AUC) for SI fibroid-to-muscle ratio on T2-weighted sequence was 0.776. For the other parameters, the AUC values were 0.512, 0.671, and 0.578, respectively. CONCLUSION: SI...

Stable isotope ratio measurements in hydrogen, nitrogen, and oxygen using Raman scattering

International Nuclear Information System (INIS)

Harney, R.C.; Bloom, S.D.; Milanovich, F.P.

1975-01-01

A method for measuring stable isotope ratios using laser Raman scattering was developed which may prove of significant utility and benefit in stable isotope tracer studies. Crude isotope ratio measurements obtained with a low-power laser indicate that with current technology it should be possible to construct an isotope ratio measurement system using laser Raman scattering that is capable of performing 0.1 percent accuracy isotope ratio measurements of 16 O/ 18 O in natural abundance oxygen gas or 14 N/ 15 N in natural abundance nitrogen gas in times less than two minutes per sample. Theory pertinent to the technique, designs of specific isotope ratio spectrometer systems, and data relating to isotope ratio measurements in hydrogen, nitrogen, and oxygen are presented. In addition, the current status of several studies utilizing this technique is discussed. (auth)

Does predation control adult sex ratios and longevities in marine pelagic copepods?

DEFF Research Database (Denmark)

Hirst, A.G.; Bonnet, D.; Conway, D.V.P.

2010-01-01

We assess the causes of adult sex ratio skew in marine pelagic copepods by examining changes in these ratios between the juveniles and adults, sexual differences in juvenile stage durations, and mortality rates of adults in the field and laboratory (when free from predators). In the field, late...... copepodite stages (CIV and CV) commonly have sex ratios that are either not significantly different from equity (1 : 1), or slightly male biased. By contrast, in adults, these ratios are commonly significantly biased toward female dominance. Sex ratio skews are therefore primarily attributable to processes...... in adults. Members of the non-Diaptomoidea have especially skewed adult ratios; in the members Oithonidae and Clausocalanidae this is not generated from differences between male and female adult physiological longevity (i.e., laboratory longevity when free of predators). In the genera Acartia, Oithona...

The spleen-to-liver ratios in hepatic diseases

International Nuclear Information System (INIS)

Vorne, M.; Jurvelin, J.; Vaehaetalo, S.; Himanka, E.

1984-01-01

We compared light pen (LPEN) and Region of Interest (ROI) computer methods in determining spleen-to-liver (S/L) ratios both in anterior and posterior images in various liver diseases. The S/L ratio was independent of age or type of colloid used (equal particle size provided). Results with corresponding LPEN and ROI programs did not differ significantly from each other. The sensitivity and specificity were tested and the anterior view yielded somewhat better results than the posterior view but the best results were obtained when both projections were used. The sensitivity for all liver diseases was 60% and the corresponding specificity 93%. In hepatocellular diseases the sensitivity was 80-100%, but the S/L ratio had only 37% sensitivity for hepatic metastases. Hepatomegaly in the anterior view was found in 67% of fatty liver cases, in 25% of cirrhosis cases, in 20% of hepatitis and in 25% of metastatic livers. Splenomegaly was noted in 39-54% of patients with hepatocellular diseases but only in 4-10% of metastatic diseases. (orig.) [de

The Determinants of Brazilian Football Clubs’ Debt Ratios

Directory of Open Access Journals (Sweden)

Marke Geisy da Silva Dantas

2017-01-01

Full Text Available This paper explores the relationship between the debt ratio of Brazilian football clubs and several potential determinants, both financial and sports-related. Our explanatory variables are Current Ratio, Return on Assets, Score Percentage, Size, 12 Biggest Clubs, Access (to specific championships, e.g. Libertadores da América , Division, Title (won at time t and Relegated (at time t . Data was collected from several publicly available channels and our sample was mostly decided according to this availability. The time range adopted was 2010-2013. The model employed was Generalized Estimating Equation. Our results suggest that debt ratios are more associated with their popularity or their participation in the highest division of its main championship rather than titles held, access to different competitions or relegation to lower levels. We believe that our findings may be useful for both practitioners, who might know the impact of their sports-related choices in their clubs’ debts, and policymakers, that could prepare differentiated policies for specific groups (e.g divisions.

Anomalous Enantiomer Ratios in Meteoritic Sugar Derivatives

Science.gov (United States)

Cooper, G.; Sant, M.; Asiyo, C.

2009-03-01

The enantiomer (mirror-image) ratios of sugar acids in carbonaceous meteorites have been measured. D-enantiomer excesses are found in all acids measured thus far. This includes rare as well as common compounds.

Sex ratio in two species of Pegoscapus wasps (Hymenoptera: Agaonidae that develop in figs: can wasps do mathematics, or play sex ratio games?

Directory of Open Access Journals (Sweden)

William Ramírez-Benavides

2009-09-01

Full Text Available The fig pollinating wasps (Hymenoptera: Agaonidae have obligate arrhenotoky and a breeding structure that fits local mate competition (LMC. It has been traditionally assumed that LMC organisms adjust the sex ratio by laying a greater proportion of male eggs when there is superparasitism (several foundresses in a host. We tested the assumption with two wasp species, Pegoscapus silvestrii, pollinator of Ficus pertusa and Pegoscapus tonduzi, pollinator of Ficus eximia (= F. citrifolia, in the Central Valley of Costa Rica. Total number of wasps and seeds were recorded in individual isolated naturally colonized syconia. There was a constant additive effect between the number of foundresses and the number of males produced in the brood of a syconium, while the number of females decreased. Both wasp species seem to have precise sex ratios and probably lay the male eggs first in the sequence, independently of superparasitism and clutch size: consequently, they have a non-random sex allocation. Each syconium of Ficus pertusa and of F. eximia colonized by one foundress had similar mean numbers of females, males, and seeds. The two species of wasps studied do not seem to adjust the sex ratio when there is superparasitism. Pollinating fig wasp behavior is better explained by those models not assuming that females do mathematical calculations according to other females’ sex ratios, size, number of foundresses, genetic constitution, clutch size or environmental conditions inside the syconium. Our results are in agreement with the constant male number hypothesis, not with sex ratio games. Rev. Biol. Trop. 57 (3: 605-621. Epub 2009 September 30.

Riparian Sediment Delivery Ratio: Stiff Diagrams and Artifical Neural Networks

Science.gov (United States)

Various methods are used to estimate sediment transport through riparian buffers and grass jilters with the sediment delivery ratio having been the most widely applied. The U.S. Forest Service developed a sediment delivery ratio using the stiff diagram and a logistic curve to int...

Influence of the cylindrical gear pairs parameters to the transverse contact ratio

Directory of Open Access Journals (Sweden)

Predrag S. Dobratić

2014-06-01

Full Text Available In the field of transmission and power transformation from the power engine to the working machine, gear pairs, are mostly used in mechanical engineering due to their compactness of the structure, high reliability and capacity. One way of improving the performance characteristics of gear pairs, and thus the gear transmitters, is to increase the number of simultaneously meshed pairs of teeth, or increasing the transverse contact ratio. To this end, this paper analyzes in detail the partial and simultaneous influence of the number of teeth and tooth profile shapes, moving through shifting coefficient and pressure angle, to the number of simultaneously meshed pairs of teeth. The obtained results allow us to define the optimum parameters of cylindrical gear pairs, in terms of the size of the transverse contact ratio. Introduction The kinematic indicator of the existence of the transmitting continuity of a rotary movement is the total contact ratio. In order to achieve the transmitting continuity of a rotary movement, the total contact ratio must be higher than one. Based on the total contact ratio, the information on the number of simultaneously meshed pairs of the teeth which rotate during the contact period is obtained. For example, if the  – one and two pairs of teeth alternately take turn, and if the  – two and three pairs of teeth alternately take turn, etc. It should be noted that the  is a necessary but not sufficient condition for achieving multiple meshes. The next condition to meet is the compatibility between the accuracy of teeth production, the teeth rigidity and the intensity of the total load of the teeth pair. The influence of the addendum coefficient on the transverse contact ratio is shown in the paper (Li, 2008. It is shown that changes in the addendum coefficient in conjunction with the corresponding values of the shifting coefficient and gear ratio can achieve the transverse contact ratio value higher than four. The paper

Preconception maternal polychlorinated biphenyl concentrations and the secondary sex ratio

International Nuclear Information System (INIS)

Taylor, Kira C.; Jackson, Leila W.; Lynch, Courtney D.; Kostyniak, Paul J.; Buck Louis, Germaine M.

2007-01-01

The secondary sex ratio is the ratio of male to female live births and historically has ranged from 102 to 106 males to 100 females. Temporal declines have been reported in many countries prompting authors to hypothesize an environmental etiology. Blood specimens were obtained from 99 women aged 24-34 prior to attempting pregnancy and quantified for 76 polychlorinated biphenyl (PCB) congeners using dual column gas chromatography with electron capture detection. Women were prospectively followed until pregnancy or 12 cycles of trying. The odds of a male birth for three PCB groupings (total, estrogenic, anti-estrogenic) controlling for maternal characteristics were estimated using logistic regression. Among the 50 women with live births and PCB data, 26 female and 24 male infants were born (ratio 0.92). After adjusting for age and body mass index, odds of a male birth were elevated among women in the second (OR=1.29) and third (OR=1.48) tertiles of estrogenic PCBs; odds (OR=0.70) were reduced among women in the highest tertile of anti-estrogenic PCBs. All confidence intervals included one. The direction of the odds ratios in this preliminary study varied by PCB groupings, supporting the need to study specific PCB patterns when assessing environmental influences on the secondary sex ratio

Econometric models for predicting confusion crop ratios

Science.gov (United States)

Umberger, D. E.; Proctor, M. H.; Clark, J. E.; Eisgruber, L. M.; Braschler, C. B. (Principal Investigator)

1979-01-01

Results for both the United States and Canada show that econometric models can provide estimates of confusion crop ratios that are more accurate than historical ratios. Whether these models can support the LACIE 90/90 accuracy criterion is uncertain. In the United States, experimenting with additional model formulations could provide improved methods models in some CRD's, particularly in winter wheat. Improved models may also be possible for the Canadian CD's. The more aggressive province/state models outperformed individual CD/CRD models. This result was expected partly because acreage statistics are based on sampling procedures, and the sampling precision declines from the province/state to the CD/CRD level. Declining sampling precision and the need to substitute province/state data for the CD/CRD data introduced measurement error into the CD/CRD models.

Direct uranium isotope ratio analysis of single micrometer-sized glass particles

International Nuclear Information System (INIS)

Kappel, Stefanie; Boulyga, Sergei F.; Prohaska, Thomas

2012-01-01

We present the application of nanosecond laser ablation (LA) coupled to a ‘Nu Plasma HR’ multi collector inductively coupled plasma mass spectrometer (MC-ICP-MS) for the direct analysis of U isotope ratios in single, 10–20 μm-sized, U-doped glass particles. Method development included studies with respect to (1) external correction of the measured U isotope ratios in glass particles, (2) the applied laser ablation carrier gas (i.e. Ar versus He) and (3) the accurate determination of lower abundant 236 U/ 238 U isotope ratios (i.e. 10 −5 ). In addition, a data processing procedure was developed for evaluation of transient signals, which is of potential use for routine application of the developed method. We demonstrate that the developed method is reliable and well suited for determining U isotope ratios of individual particles. Analyses of twenty-eight S1 glass particles, measured under optimized conditions, yielded average biases of less than 0.6% from the certified values for 234 U/ 238 U and 235 U/ 238 U ratios. Experimental results obtained for 236 U/ 238 U isotope ratios deviated by less than −2.5% from the certified values. Expanded relative total combined standard uncertainties U c (k = 2) of 2.6%, 1.4% and 5.8% were calculated for 234 U/ 238 U, 235 U/ 238 U and 236 U/ 238 U, respectively. - Highlights: ► LA-MC-ICP-MS was fully validated for the direct analysis of individual particles. ► Traceability was established by using an IRMM glass particle reference material. ► Measured U isotope ratios were in agreement with the certified range. ► A comprehensive total combined uncertainty evaluation was performed. ► The analysis of 236 U/ 238 U isotope ratios was improved by using a deceleration filter.

The ratio of structure functions for the neutron and the proton

International Nuclear Information System (INIS)

Ballintijn, M.K.

1994-01-01

The subject of this thesis is the ratio of the structure functions F 2 of the deuteron and the proton. The structure function ratio is measured by the NMC with high precision due to a dedicated target setup. In this thesis the analysis is presented of the data taken in 1989, which were obtained using incident muon energies of 120, 200 and 280 GeV. These data complement the results from earlier measurements performed in 1986 and 1987 which were obtained at 90 and 280 GeV incident muon energy. The newly determined structure function ratio, in a slightly extended range of the scaling parameter x, is compared to the previous one and is found to be in good agreement. All data are combined to give the most accurate determination of the structure function ratio to date. The results are used to determine the dependence of the structure function ratio on the value of Q 2 , the scale at which the nucleon is probed. Finally, the structure function ratios obtained at four different incident muon energies separately, are used to determine the difference R d -R p , where R is the ratio of cross sections for the absorption of longitudinally and transversely polarized virtual photons. The difference in R for the deuteron and the proton is related to differences in the gluon distribution. The result is compatible with a gluon distribution that is identical for the deuteron and the proton. The degree of equality of R d and R p is a measure for the correctness of the procedure to extract structure function ratios. The present result is R d -R p =0.02±0.02 and hence compatible with zero. (orig.)

The impact of sex ratio and economic status on local birth rates

OpenAIRE

Chipman, A.; Morrison, E.

2013-01-01

Human mating and reproductive behaviour can vary depending on various mechanisms, including the local sex ratio. Previous research shows that as sex ratios become female-biased, women from economically deprived areas are less likely to delay reproductive opportunities to wait for a high-investing mate but instead begin their reproductive careers sooner. Here, we show that the local sex ratio also has an impact on female fertility schedules. At young ages, a female-biased ratio is associated w...

Blind deblurring of spiral CT images - comparative studies on edge-to-noise ratios

International Nuclear Information System (INIS)

Jiang Ming; Wan Ge; Skinner, Margaret W.; Rubinstein, Jay T.; Vannier, Michael W.

2002-01-01

A recently developed blind deblurring algorithm based on the edge-to-noise ratio has been applied to improve the quality of spiral CT images. Since the discrepancy measure used to quantify the edge and noise effects is not symmetric, there are several ways to formulate the edge-to-noise ratio. This article is to investigate the performance of those ratios with phantom and patient data. In the phantom study, it is shown that all the ratios share similar properties, validating the blind deblurring algorithm. The image fidelity improvement varies from 29% to 33% for different ratios, according to the root mean square error (RMSE) criterion; the optimal iteration number determined for each ratio varies from 25 to 35. Those ratios that are associated with most satisfactory performance are singled out for the image fidelity improvement of about 33% in the numerical simulation. After automatic blind deblurring with the selected ratios, the spatial resolution of CT is substantially refined in all the cases tested

Human sex ratio at amniocentesis and at birth in Taiwan

Directory of Open Access Journals (Sweden)

I-Wen Lee

2012-12-01

Conclusions: The results showed that sex ratio was already skewed toward male at midtrimester. Our data imply that artificial sex selection, if it were present, might have already emerged prior to the timing of amniocentesis. However, more large nationwide studies on sex ratios in Taiwan are warranted.

Pupil – Teacher Ratio: Implication for Quality Education in Nigeria ...

African Journals Online (AJOL)

Significantly, pupil-teacher ratios are very essential to quality of education. They perhaps rank alongside professional knowledge, skill, as well as strategies, in genuinely determining educational success and performance. This paper discusses pupil-teacher ratio and relevance that pupils seem to have a greater impact on ...

On efficiency of some ratio estimators in double sampling design ...

African Journals Online (AJOL)

In this paper, three sampling ratio estimators in double sampling design were proposed with the intention of finding an alternative double sampling design estimator to the conventional ratio estimator in double sampling design discussed by Cochran (1997), Okafor (2002) , Raj (1972) and Raj and Chandhok (1999).

Deep Reactive Ion Etching for High Aspect Ratio Microelectromechanical Components

DEFF Research Database (Denmark)

Jensen, Søren; Yalcinkaya, Arda Deniz; Jacobsen, S.

2004-01-01

A deep reactive ion etch (DRIE) process for fabrication of high aspect ratio trenches has been developed. Trenches with aspect ratios exceeding 20 and vertical sidewalls with low roughness have been demonstrated. The process has successfully been used in the fabrication of silicon-on-insulator (SOI...

Sex ratios in the Arctic--do man-made chemicals matter?

DEFF Research Database (Denmark)

Bjerregaard, Peter; Chatwood, Susan; Denning, Bryany

2013-01-01

The objective was to analyze the variation of secondary sex ratios across the Arctic and to estimate the time trend. The rationale for this was claims in news media that, in the Arctic, sex ratios have become reduced due to exposure to anthropogenic contaminants in the environment....

Concept of planetary gear system to control fluid mixture ratio

Science.gov (United States)

Mcgroarty, J. D.

1966-01-01

Mechanical device senses and corrects for fluid flow departures from the selected flow ratio of two fluids. This system has been considered for control of rocket engine propellant mixture control but could find use wherever control of the flow ratio of any two fluids is desired.

Neutrophil Lymphocyte Ratio Predicts Postoperative Pain after ...

African Journals Online (AJOL)

2018-02-07

Feb 7, 2018 ... between preoperatively measured neutrophil-lymphocyte ratio (NLR) – as an inflammation ... analgesic (tenoxicam – as the first drug of choice, paracetamol, tramadol, or pethidine) usage ... fracture fixation). Age, sex, type of ...

Is combination of neutrophil to lymphocyte ratio and platelet lymphocyte ratio a useful predictor of postoperative survival in patients with esophageal squamous cell carcinoma?

Directory of Open Access Journals (Sweden)

Tanoglu A

2014-03-01

Full Text Available Alpaslan Tanoglu,1 Ergenekon Karagoz,2 Nurettin Yiyit,3 Ufuk Berber4 1Department of Gastroenterology, 2Department of Infectious Diseases and Clinical Microbiology, 3Department of Thoracic Surgery, 4Department of Pathology, GATA Haydarpasa Training Hospital, Uskudar, TurkeyWe read with interest the recent article entitled "Combination of neutrophil to lymphocyte ratio and platelet lymphocyte ratio is a useful predictor of postoperative survival in patients with esophageal squamous cell carcinoma" by Feng et al.1 In their study, authors aimed to investigate the usefulness of a novel inflammation-based prognostic system, using the combination of neutrophil lymphocyte ratio (NLR and platelet lymphocyte ratio (PLR, for predicting survival in patients with esophageal squamous cell carcinoma (ESCC. Finally, they concluded that combination of NLR and PLR is a useful predictor of postoperative survival in patients with ESCC and combination of these parameters is superior to NLR or PLR as a predictive factor in patients with ESCC. We would like to thank the authors for their contribution.View original paper by Feng and colleagues.

Evaluation of compression ratio using JPEG 2000 on diagnostic images in dentistry

International Nuclear Information System (INIS)

Jung, Gi Hun; Han, Won Jeong; Yoo, Dong Soo; Kim, Eun Kyung; Choi, Soon Chul

2005-01-01

To find out the proper compression ratios without degrading image quality and affecting lesion detectability on diagnostic images used in dentistry compressed with JPEG 2000 algorithm. Sixty Digora peri apical images, sixty panoramic computed radiographic (CR) images, sixty computed tomography (CT) images, and sixty magnetic resonance (MR) images were compressed into JPEG 2000 with ratios of 10 levels from 5:1 to 50:1. To evaluate the lesion detectability, the images were graded with 5 levels (1 : definitely absent ; 2 : probably absent ; 3 : equivocal ; 4 : probably present ; 5 : definitely present), and then receiver operating characteristic analysis was performed using the original image as a gold standard. Also to evaluate subjectively the image quality, the images were graded with 5 levels (1 : definitely unacceptable ; 2 : probably unacceptable ; 3 : equivocal ; 4 : probably acceptable ; 5 : definitely acceptable), and then paired t-test was performed. In Digora, CR panoramic and CT images, compressed images up to ratios of 15:1 showed nearly the same lesion detectability as original images, and in MR images, compressed images did up to ratios of 25:1. In Digora and CR panoramic images, compressed images up to ratios of 5:1 showed little difference between the original and reconstructed images in subjective assessment of image quality. In CT images, compressed images did up to ratios of 10:1 and in MR images up to ratios of 15:1. We considered compression ratios up to 5:1 in Digora and CR panoramic images, up to 10:1 in CT images, up to 15:1 in MR images as clinically applicable compression ratios.

Non-linearity of the response accommodative convergence to accommodation ratio.

Science.gov (United States)

Johnston, Miriam S; Firth, Alison Y

2013-09-01

Previous studies have reported variation in stimulus accommodative convergence to accommodation (AC/A) ratio across differing accommodative stimuli. Response AC/A ratio was assessed across 4 accommodative demands to determine if these differences could be due to accommodative inaccuracies to stimuli. Twenty-three student participants aged 18 to 26 years (mean age 20.3 ± 1.7 years) successfully completed all testing conditions. The modified Thorington technique was used at 4 m to measure heterophoria. The Shin Nippon SRW 5000 infrared autorefractor was used to determine accommodative change to -1.50, -3.00, -4.50, and -6.00D lens stimuli. Significant differences were found in response AC/A ratio between different minus lens stimulated accommodative demands (p accommodative stimuli, but tended to increase with accommodative demand. Significant variability in response AC/A ratio was found, both within individuals to different accommodative demands, and between individuals across the data set.

Evaluation of electrical impedance ratio measurements in accuracy of electronic apex locators.

Science.gov (United States)

Kim, Pil-Jong; Kim, Hong-Gee; Cho, Byeong-Hoon

2015-05-01

The aim of this paper was evaluating the ratios of electrical impedance measurements reported in previous studies through a correlation analysis in order to explicit it as the contributing factor to the accuracy of electronic apex locator (EAL). The literature regarding electrical property measurements of EALs was screened using Medline and Embase. All data acquired were plotted to identify correlations between impedance and log-scaled frequency. The accuracy of the impedance ratio method used to detect the apical constriction (APC) in most EALs was evaluated using linear ramp function fitting. Changes of impedance ratios for various frequencies were evaluated for a variety of file positions. Among the ten papers selected in the search process, the first-order equations between log-scaled frequency and impedance were in the negative direction. When the model for the ratios was assumed to be a linear ramp function, the ratio values decreased if the file went deeper and the average ratio values of the left and right horizontal zones were significantly different in 8 out of 9 studies. The APC was located within the interval of linear relation between the left and right horizontal zones of the linear ramp model. Using the ratio method, the APC was located within a linear interval. Therefore, using the impedance ratio between electrical impedance measurements at different frequencies was a robust method for detection of the APC.

Dilution Ratios for HB Line Phase I Eductor System

International Nuclear Information System (INIS)

Steimke, J.L.

2002-01-01

HB Line Phase I product transfer includes an eductor which transfers liquid from Product Hold Tank (PHT) RT-33 or RT-34 to Tank 11.1. The eductor also dilutes the liquid from the PHT with eductant. Dilution must be reliably controlled because of criticality concerns with H Canyon Tanks. The eductor system, which contains a 1 inch Model 264 Schutte and Koerting eductor, was previously modeled [1] in 1998 and dilution ratios were calculated for different flow restrictors, eductant pressures and densities for the eductant and the contents of the PHT. The previous calculation was performed using spreadsheet software no longer supported at SRS. For the previous work dilution ratio was defined as the volume of eductant consumed divided by volume of PHT contents transferred. Since 1998 HB Line Engineering has changed the definition of dilution ratio to the total volume of liquid, eductant consumed plus the volume of PHT liquid transferred, divided by the volume of PHT liquid transferred. The 1998 base case calculation was for a restrictor diameter of 0.334 inches, an eductant supply pressure of 15 psig, full PHT, an eductant specific gravity of 1.385 and a PHT density of 1.015. The base case dilution ratio calculated in 1998 using the current definition was 3.52. After accounting for uncertainty the minimum dilution ratio decreased to 3.23. In 2001 HB Line Engineering requested that the calculation be repeated for a manganous nitrate solution eductant and also a process water eductant. The other conditions were the same as for the 1998 calculation. The objective of this report is to document the calculations and the results

Association of secondary sex ratio with smoking and parity.

Science.gov (United States)

Beratis, Nicholas G; Asimacopoulou, Aspasia; Varvarigou, Anastasia

2008-03-01

To assess the sex ratio in offspring of smoking and nonsmoking mothers in relationship to parity. Prospective study. University hospital. The authors studied 2,108 term singleton neonates born between 1993 and 2002, 665 from smoking mothers and 1,443 from nonsmoking mothers. A prospective recording of maternal age, parity and smoking status, and gender of neonates delivered over a 10-year period. Secondary sex ratio in regard to maternal smoking and parity. The offspring sex ratio in the total sample studied was 1.09; in the offspring of smoking and nonsmoking mothers, it was 1.26 and 1.03, respectively, a statistically significant difference. In the offspring of smoking women who had parity 1, 2, and >or=3, it was 1.47, 1.35, and 0.92, whereas in those of nonsmoking women, it was 1.04, 1.00, and 1.03, respectively (the differences of the parity 1 and 2 groups between the offspring of smoking and nonsmoking mothers were statistically significant). Logistic regression analysis showed that the possibility of a boy being delivered by a mother who smoked was significantly greater in primiparous women than in women who had parity >or=3, independent of the maternal age. Conversely, parity did not affect significantly the sex ratio in the offspring of nonsmoking women. The findings suggest that among women who smoked, significantly more male than female offspring are born from primiparous women, whereas women who had parity >or=3 gave birth to more female offspring; biparous women give birth to significantly more male offspring, but the offspring sex ratio declined with the number of cigarettes when the mothers smoked >or=10 cigarettes per day.

Prediction of Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma by Using Neutrophil to Lymphocyte Ratio and Platelet to Lymphocyte Ratio.

Science.gov (United States)

Ozgonul, Cem; Sertoglu, Erdim; Mumcuoglu, Tarkan; Ozge, Gokhan; Gokce, Gokcen

2016-12-01

To assess the levels of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in patients with pseudoexfoliation syndrome (PEX) and to compare the NLR and PLR results of patients with PEX, PEX glaucoma (PXG), and healthy controls. In total, 34 patients with PEX, 29 patients with PXG, and 42 healthy subjects were enrolled in this retrospective study. Complete ophthalmologic examination and complete blood count measurements were performed of all subjects. Complete blood counts were performed within 2 h of blood collection. There was a significant difference in NLR between PEX and control groups (p = 0.012) and PXG and control groups (p = 0.003). Also, a significant difference was found in PLR values between control and PXG groups (p = 0.024). Our study for the first time provides evidence that PLR and NLR may be useful for predicting the prognosis of PEX patients and progression to PXG.

Baryon-to-dark matter ratio from random angular fields

International Nuclear Information System (INIS)

McDonald, John

2013-01-01

We consider the baryon-to-dark matter ratio in models where the dark matter and baryon densities depend on angular fields θ d and θ b according to ρ d ∝θ d α and ρ b ∝θ b β , with all values of θ d and θ b being equally probable in a given randomly-selected domain. Under the assumption that anthropic selection depends primarily on the baryon density in galaxies at spherical collapse, we show that the probability density function for the baryon-to-dark matter ratio r = Ω B /Ω DM is purely statistical in nature and is independent of anthropic selection. We compute the probability density function for r as a function of α and β and show that the observed value of the baryon-to-dark matter ratio, r ≈ 1/5, is natural in this framework

Rapid Development, Build-Out Ratio and Subsequent Neighborhood Turnover

Directory of Open Access Journals (Sweden)

George O. Rogers

2018-04-01

Full Text Available Neighborhood development is primarily comprised of structural elements that include design elements, nearby amenities and ecological attributes. This paper assumes that the process of development itself also influences the character of the neighborhood—specifically, that the rate of development and build-out ratio influences neighborhood turnover. While the structural components clearly set a framework for development, the process of development expresses the character of the neighborhood in subtle messages conveyed through the market. Neighborhoods in the rapidly growing university town of College Station, Texas are analyzed in terms of neighborhood design, nearby amenities and landscape ecology components. Residential property records are used to characterize each neighborhood in terms of the rate of development and current build-out ratio. The multivariate analysis indicates that the development rate increases subsequent neighborhood turnover rates while the build-out ratio decreases it.

Inequalities in mortality: study rates, not standardised mortality ratios [Letter

NARCIS (Netherlands)

Bonneux, L.G.A.

2010-01-01

In their study from 1921 to 2007 Thomas and colleagues conclude on the basis of standardised mortality ratios that inequalities in mortality continue to rise and are now almost as high as in the 1930s. Relative ratios are, however, misleading when absolute rates change strongly. I calculated the

Staff/population ratios in South African public sector mental health ...

African Journals Online (AJOL)

To document existing staff/population ratios per 100 000 population in South African public sector mental health services. Design. Cross-sectional survey. ... The staff/population ratios per 100 000 population for selected personnel categories (with the interprovincial ranges in brackets) were as follows: total nursing staff 15.6 ...

Effect of Aspect Ratio, Channel Orientation, Rib Pitch-to-Height Ratio, and Number of Ribbed Walls on Pressure Drop Characteristics in a Rotating Channel with Detached Ribs

Directory of Open Access Journals (Sweden)

K. Arun

2007-01-01

Full Text Available The present work involves experimental investigation of the effects of aspect ratio, channel orientation angle, rib pitch-to-height ratio (P/e, and number of ribbed walls on friction factor in orthogonally rotating channel with detached ribs. The ribs are separated from the base wall to provide a small region of flow between the base wall and the ribs. Experiments have been conducted at Reynolds number ranging from 10000–17000 with rotation numbers varying from 0–0.38. Pitch-to-rib height ratios (P/e of 5 and 10 at constant rib height-to-hydraulic diameter ratio (e/D of 0.1 and a clearance ratio (C/e of 0.38 are considered. The rib angle of attack with respect to mainstream flow is 90∘. The channel orientation at which the ribbed wall becomes trailing surface (pressure side on which the Coriolis force acts is considered as the 0∘ orientation angle. For one-wall ribbed case, channel is oriented from 0∘ to 180∘ about its axis in steps of 30∘ to change the orientation angle. For two-wall ribbed case, the orientation angle is changed from 0∘ to 90∘ in steps of 30∘. Friction factors for the detached ribbed channels are compared with the corresponding attached ribbed channel. It is found that in one-wall detached ribbed channel, increase in the friction factor ratio with the orientation angle is lower for rectangular channel compared to that of square channel for both the pitch-to-rib height ratios of 5 and 10 at a given Reynolds number and rotation number. Friction factor ratios of two-wall detached ribbed rectangular channel are comparable with corresponding two-wall detached ribbed square channel both under stationary and rotating conditions.

Comparison of conventional hamstring/quadriceps ratio between genders in level-matched soccer players

Directory of Open Access Journals (Sweden)

M. Pellicer-Chenoll

2017-03-01

Conclusions: For both men and women, the results showed lower ratios in the non-dominant leg compared to the dominant leg. At higher velocities, the force ratios were higher, while in more knee-flexed positions, the ratios were lower. Finally, we did not find differences in ratios between men and women.

The ratio method: a new way to look at halo nuclei

Directory of Open Access Journals (Sweden)

Capel P.

2014-03-01

Full Text Available A new reaction observable is presented to study exotic loosely-bound structures, such as halo nuclei. It consists of the ratio of two angular distributions, e. g. one for breakup and one for elastic scattering. This ratio is nearly independent of the reaction mechanism and is very sensitive to the projectile structure. This new ratio method is illustrated on the particular case of 11Be, the archetypal one-neutron halo nucleus.

The influence of pressure ratio on the regenerator performance

Science.gov (United States)

Lin, Y.; Zhu, S.

2017-12-01

For a multi-stage pulse tube refrigerator with displacer, improving the regenerator efficiency is important. A displacer can get higher operating pressure ratio compared with inertance tube. The pressure ratio and porosity influence on the regenerator performance with is discussed, and CFD simulation is done on a two-stage pulse tube refrigerator with displacer to show that mass flow rate and pressure wave relation in the regenerator can be realized by a step-displacer.

Analytic Investigation Into Effect of Population Heterogeneity on Parameter Ratio Estimates

International Nuclear Information System (INIS)

Schinkel, Colleen; Carlone, Marco; Warkentin, Brad; Fallone, B. Gino

2007-01-01

Purpose: A homogeneous tumor control probability (TCP) model has previously been used to estimate the α/β ratio for prostate cancer from clinical dose-response data. For the ratio to be meaningful, it must be assumed that parameter ratios are not sensitive to the type of tumor control model used. We investigated the validity of this assumption by deriving analytic relationships between the α/β estimates from a homogeneous TCP model, ignoring interpatient heterogeneity, and those of the corresponding heterogeneous (population-averaged) model that incorporated heterogeneity. Methods and Materials: The homogeneous and heterogeneous TCP models can both be written in terms of the geometric parameters D 50 and γ 50 . We show that the functional forms of these models are similar. This similarity was used to develop an expression relating the homogeneous and heterogeneous estimates for the α/β ratio. The expression was verified numerically by generating pseudo-data from a TCP curve with known parameters and then using the homogeneous and heterogeneous TCP models to estimate the α/β ratio for the pseudo-data. Results: When the dominant form of interpatient heterogeneity is that of radiosensitivity, the homogeneous and heterogeneous α/β estimates differ. This indicates that the presence of this heterogeneity affects the value of the α/β ratio derived from analysis of TCP curves. Conclusions: The α/β ratio estimated from clinical dose-response data is model dependent-a heterogeneous TCP model that accounts for heterogeneity in radiosensitivity will produce a greater α/β estimate than that resulting from a homogeneous TCP model

Generalized characteristic ratios assignment for commensurate fractional order systems with one zero.

Science.gov (United States)

Tabatabaei, Mohammad

2017-07-01

In this paper, a new method for determination of the desired characteristic equation and zero location of commensurate fractional order systems is presented. The concept of the characteristic ratio is extended for zero-including commensurate fractional order systems. The generalized version of characteristic ratios is defined such that the time-scaling property of characteristic ratios is also preserved. The monotonicity of the magnitude frequency response is employed to assign the generalized characteristic ratios for commensurate fractional order transfer functions with one zero. A simple pattern for characteristic ratios is proposed to reach a non-overshooting step response. Then, the proposed pattern is revisited to reach a low overshoot (say for example 2%) step response. Finally, zero-including controllers such as fractional order PI or lag (lead) controllers are designed using generalized characteristic ratios assignment method. Numerical simulations are provided to show the efficiency of the so designed controllers. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Measurement of the super-allowed branching ratio of $^{22}$Mg

CERN Multimedia

We propose to measure the super-allowed branching ratio and the half-life of $^{22}$Mg, one of the least-well-measured $0^{+} \\rightarrow 0^{+}$ transitions of the 14 nuclei used to determine V$_{ud}$ and to test the unitarity of the CKM matrix. We propose measurements which should allow to significantly improve the precision on the super-allowed branching ratio employing a precisely efficiency calibrated germanium detector and on the half-life. As no method exists to greatly improve (e.g. an order of magnitude) on previous results, the branching ratio and the half-life have to be measured several times with independent methods and in independent experiments.

Effect of sodium adsorption ratio and electric conductivity of the ...

African Journals Online (AJOL)

of the water and its sodium content relative to calcium and magnesium content. ... calcium and magnesium is the sodium adsorption ratio (SAR). It is a measure of the ..... comparison of ANN and geo statistics methods for estimating spatial distribution of sodium adsorption ratio (SAR) in groundwater. Int. J. Agric. Crop Sci.

Child-to-Teacher Ratio and Day Care Teacher Sickeness Absenteeism

DEFF Research Database (Denmark)

Gørtz, Mette; Andersson, Elvira

2014-01-01

time periods, 2002–2003 and 2005–2006, by using generalized method of moments with lagged levels of the child-to-teacher ratio as instrument. Our estimation results are somewhat mixed. Generally, the results indicate that the child-to-teacher ratio is positively related to short-term sickness absence...

Fat to muscle ratio measurements with dual energy x-ray absorbtiometry

Energy Technology Data Exchange (ETDEWEB)

Chen, A. [Shenzhen College of International Education, 1st HuangGang Park St., Shenzhen, GuangDong (China); Luo, J. [Department of Biomedical Engineering, University at Buffalo, 332 Bonner Hall, Buffalo, NY 14260-1920 (United States); Wang, A. [Department of Computer Science, Carnegie Mellon University, Pittsburgh, PA 15213 (United States); Broadbent, C. [School of Engineering, Columbia University, 1130 Amsterdam Av., New York, NY 10027 (United States); Zhong, J. [Department of English, Dartmouth College, 6032 Sanborn House, Hanover, NH 03755 (United States); Dilmanian, F.A. [Departments of Radiation Oncology, Neurology, and Radiology, Stony Brook University, Stony Brook, NY 11794 (United States); Zafonte, F.; Zhong, Z. [National Synchrotron Light Source II, Brookhaven National Laboratory, Bldg. 743, Upton, NY 11973 (United States)

2015-07-11

Accurate measurement of the fat-to-muscle ratio in animal model is important for obesity research. An efficient way to measure the fat to muscle ratio in animal model using dual-energy absorptiometry is presented in this paper. A radioactive source exciting x-ray fluorescence from a target material is used to provide the two x-ray energies needed. The x-rays, after transmitting through the sample, are measured with an energy-sensitive Ge detector. Phantoms and specimens were measured. The results showed that the method was sensitive to the fat to muscle ratios with good linearity. A standard deviation of a few percent in the fat to muscle ratio could be observed with the x-ray dose of 0.001 mGy.

Air/fuel ratio visualization in a diesel spray

Science.gov (United States)

Carabell, Kevin David

1993-01-01

To investigate some features of high pressure diesel spray ignition, we have applied a newly developed planar imaging system to a spray in an engine-fed combustion bomb. The bomb is designed to give flow characteristics similar to those in a direct injection diesel engine yet provide nearly unlimited optical access. A high pressure electronic unit injector system with on-line manually adjustable main and pilot injection features was used. The primary scalar of interest was the local air/fuel ratio, particularly near the spray plumes. To make this measurement quantitative, we have developed a calibration LIF technique. The development of this technique is the key contribution of this dissertation. The air/fuel ratio measurement was made using biacetyl as a seed in the air inlet to the engine. When probed by a tripled Nd:YAG laser the biacetyl fluoresces, with a signal proportional to the local biacetyl concentration. This feature of biacetyl enables the fluorescent signal to be used as as indicator of local fuel vapor concentration. The biacetyl partial pressure was carefully controlled, enabling estimates of the local concentration of air and the approximate local stoichiometry in the fuel spray. The results indicate that the image quality generated with this method is sufficient for generating air/fuel ratio contours. The processes during the ignition delay have a marked effect on ignition and the subsequent burn. These processes, vaporization and pre-flame kinetics, very much depend on the mixing of the air and fuel. This study has shown that poor mixing and over-mixing of the air and fuel will directly affect the type of ignition. An optimal mixing arrangement exists and depends on the swirl ratio in the engine, the number of holes in the fuel injector and the distribution of fuel into a pilot and main injection. If a short delay and a diffusion burn is desired, the best mixing parameters among those surveyed would be a high swirl ratio, a 4-hole nozzle and a

Using 2D: 4D digit ratios to determine motor skills in children.

Science.gov (United States)

Wang, Y; Wang, H-L; Li, Y-H; Zhu, F-L; Li, S-J; Ni, H

2016-03-01

In past few decades, there has an outburst of research surrounding second to fourth finger digit ratio (2D:4D) and its relation to prenatal sex steroids including both testosterone and estrogen. In utero, testosterone and estrogen are responsible for the differences in digit ratio between the genders. Recent research has tried to extend past the influence of steroids and look at the potential effect of digit ratios on fine and gross motor skills in children. We compiled the current understanding of the connection between sex hormones and the development of the 2D:4D ratio as well as the effect the ratio has on motor skills. There seems to be a significant positive correlation between 2D:4D digit ratio and precision of fine motor skill. In addition, there is a negative correlation between 2D:4D ratio and speed of fine motor activity. In this review, we will outline the use of 2D:4D ratio as a biomarker for prenatal sex steroids and through that, a proxy marker for fine and gross motor skills.

Millimeter-wave Line Ratios and Sub-beam Volume Density Distributions

Energy Technology Data Exchange (ETDEWEB)

Leroy, Adam K.; Gallagher, Molly [Department of Astronomy, The Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Usero, Antonio [Observatorio Astronmico Nacional (IGN), C/Alfonso XII, 3, E-28014 Madrid (Spain); Schruba, Andreas [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße 1, D-85748 Garching (Germany); Bigiel, Frank [Institute für theoretische Astrophysik, Zentrum für Astronomie der Universität Heidelberg, Albert-Ueberle Str. 2, D-69120 Heidelberg (Germany); Kruijssen, J. M. Diederik; Schinnerer, Eva [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstraße 12-14, D-69120 Heidelberg (Germany); Kepley, Amanda [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Blanc, Guillermo A. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Bolatto, Alberto D. [Department of Astronomy, Laboratory for Millimeter-wave Astronomy, and Joint Space Institute, University of Maryland, College Park, MD 20742 (United States); Cormier, Diane; Jiménez-Donaire, Maria J. [Max Planck Institute für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Hughes, Annie [CNRS, IRAP, 9 av. du Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France); Rosolowsky, Erik [Department of Physics, University of Alberta, Edmonton, AB (Canada)

2017-02-01

We explore the use of mm-wave emission line ratios to trace molecular gas density when observations integrate over a wide range of volume densities within a single telescope beam. For observations targeting external galaxies, this case is unavoidable. Using a framework similar to that of Krumholz and Thompson, we model emission for a set of common extragalactic lines from lognormal and power law density distributions. We consider the median density of gas that produces emission and the ability to predict density variations from observed line ratios. We emphasize line ratio variations because these do not require us to know the absolute abundance of our tracers. Patterns of line ratio variations have the potential to illuminate the high-end shape of the density distribution, and to capture changes in the dense gas fraction and median volume density. Our results with and without a high-density power law tail differ appreciably; we highlight better knowledge of the probability density function (PDF) shape as an important area. We also show the implications of sub-beam density distributions for isotopologue studies targeting dense gas tracers. Differential excitation often implies a significant correction to the naive case. We provide tabulated versions of many of our results, which can be used to interpret changes in mm-wave line ratios in terms of adjustments to the underlying density distributions.

Likelihood ratio sequential sampling models of recognition memory.

Science.gov (United States)

Osth, Adam F; Dennis, Simon; Heathcote, Andrew

2017-02-01

The mirror effect - a phenomenon whereby a manipulation produces opposite effects on hit and false alarm rates - is benchmark regularity of recognition memory. A likelihood ratio decision process, basing recognition on the relative likelihood that a stimulus is a target or a lure, naturally predicts the mirror effect, and so has been widely adopted in quantitative models of recognition memory. Glanzer, Hilford, and Maloney (2009) demonstrated that likelihood ratio models, assuming Gaussian memory strength, are also capable of explaining regularities observed in receiver-operating characteristics (ROCs), such as greater target than lure variance. Despite its central place in theorising about recognition memory, however, this class of models has not been tested using response time (RT) distributions. In this article, we develop a linear approximation to the likelihood ratio transformation, which we show predicts the same regularities as the exact transformation. This development enabled us to develop a tractable model of recognition-memory RT based on the diffusion decision model (DDM), with inputs (drift rates) provided by an approximate likelihood ratio transformation. We compared this "LR-DDM" to a standard DDM where all targets and lures receive their own drift rate parameters. Both were implemented as hierarchical Bayesian models and applied to four datasets. Model selection taking into account parsimony favored the LR-DDM, which requires fewer parameters than the standard DDM but still fits the data well. These results support log-likelihood based models as providing an elegant explanation of the regularities of recognition memory, not only in terms of choices made but also in terms of the times it takes to make them. Copyright © 2016 Elsevier Inc. All rights reserved.

THE CORRELATION BETWEEN THE AUTONOMY RATIO AND THE RETURN ON EQUITY

OpenAIRE

Daniel BRÎNDESCU – OLARIU

2014-01-01

Previous studies conducted over companies from the Timis County indicate a negative correlation between the autonomy ratio and the bankruptcy risk. At the same time, high values of the autonomy ratio could have a negative effect on the return on equity. The current study aims to evaluate the relationship between the autonomy ratio and the return on equity. The target population included all the companies from the Timis County that have submitted financial statements to the fiscal authoriti...

Density ratios in compressions driven by radiation pressure

International Nuclear Information System (INIS)

Lee, S.

1988-01-01

It has been suggested that in the cannonball scheme of laser compression the pellet may be considered to be compressed by the 'brute force' of the radiation pressure. For such a radiation-driven compression, an energy balance method is applied to give an equation fixing the radius compression ratio K which is a key parameter for such intense compressions. A shock model is used to yield specific results. For a square-pulse driving power compressing a spherical pellet with a specific heat ratio of 5/3, a density compression ratio Γ of 27 is computed. Double (stepped) pulsing with linearly rising power enhances Γ to 1750. The value of Γ is not dependent on the absolute magnitude of the piston power, as long as this is large enough. Further enhancement of compression by multiple (stepped) pulsing becomes obvious. The enhanced compression increases the energy gain factor G for a 100 μm DT pellet driven by radiation power of 10 16 W from 6 for a square pulse power with 0.5 MJ absorbed energy to 90 for a double (stepped) linearly rising pulse with absorbed energy of 0.4 MJ assuming perfect coupling efficiency. (author)

Oscillatory convection in low aspect ratio Czochralski melts

Science.gov (United States)

Anselmo, A.; Prasad, V.; Koziol, J.; Gupta, K. P.

1993-11-01

Modeling of the crucible in bulk crystal growth simulations as a right circular cylinder may be adequate for high aspect ratio melts but this may be unrealistic when the melt height is low. Low melt height is a unique feature of a solid feed continuous Czochralski growth process for silicon single crystals currently under investigation. At low melt heights, the crucible bottom curvature has a dampening effect on the buoyancy-induced oscillations, a source of inhomogeneities in the grown crystal. The numerical results demonstrate how the mode of convection changes from vertical wall-dominated recirculating flows to Benard convection as the aspect ratio is lowered. This phenomenon is strongly dependent on the boundary condition at the free surface of the melt, which has been generally considered to be either adiabatic or radiatively cooled. A comparison of the flow oscillations in crucibles with and without curved bottoms at aspect ratios in the range of 0.25 to 0.50, and at realistic Grashof numbers (10 7 < Gr < 10 8) illustrate that changing the shape of the crucible may be an effective means of suppressing oscillations and controlling the melt flow.

21 CFR 862.1455 - Lecithin/sphingomyelin ratio in amniotic fluid test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lecithin/sphingomyelin ratio in amniotic fluid... Clinical Chemistry Test Systems § 862.1455 Lecithin/sphingomyelin ratio in amniotic fluid test system. (a) Identification. A lecithin/sphingomyelin ratio in amniotic fluid test system is a device intended to measure the...

Evaluation of electrical impedance ratio measurements in accuracy of electronic apex locators

Directory of Open Access Journals (Sweden)

Pil-Jong Kim

2015-05-01

Full Text Available Objectives The aim of this paper was evaluating the ratios of electrical impedance measurements reported in previous studies through a correlation analysis in order to explicit it as the contributing factor to the accuracy of electronic apex locator (EAL. Materials and Methods The literature regarding electrical property measurements of EALs was screened using Medline and Embase. All data acquired were plotted to identify correlations between impedance and log-scaled frequency. The accuracy of the impedance ratio method used to detect the apical constriction (APC in most EALs was evaluated using linear ramp function fitting. Changes of impedance ratios for various frequencies were evaluated for a variety of file positions. Results Among the ten papers selected in the search process, the first-order equations between log-scaled frequency and impedance were in the negative direction. When the model for the ratios was assumed to be a linear ramp function, the ratio values decreased if the file went deeper and the average ratio values of the left and right horizontal zones were significantly different in 8 out of 9 studies. The APC was located within the interval of linear relation between the left and right horizontal zones of the linear ramp model. Conclusions Using the ratio method, the APC was located within a linear interval. Therefore, using the impedance ratio between electrical impedance measurements at different frequencies was a robust method for detection of the APC.

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

Energy Technology Data Exchange (ETDEWEB)

Tripathi, Markandey M.; Krishnan, Sundar R.; Srinivasan, Kalyan K.; Yueh, Fang-Yu; Singh, Jagdish P.

2011-09-07

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 the 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.

Explorations in Statistics: The Analysis of Ratios and Normalized Data

Science.gov (United States)

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…

Optimal Fisher Discriminant Ratio for an Arbitrary Spatial Light Modulator

Science.gov (United States)

Juday, Richard D.

1999-01-01

Optimizing the Fisher ratio is well established in statistical pattern recognition as a means of discriminating between classes. I show how to optimize that ratio for optical correlation intensity by choice of filter on an arbitrary spatial light modulator (SLM). I include the case of additive noise of known power spectral density.

Effects of Aspect Ratio on Water Immersion into Deep Silica Nanoholes.

Science.gov (United States)

Zheng, Jing; Zhang, Junqiao; Tan, Lu; Li, Debing; Huang, Liangliang; Wang, Qi; Liu, Yingchun

2016-08-30

Understanding the influence of aspect ratio on water immersion into silica nanoholes is of significant importance to the etching process of semiconductor fabrication and other water immersion-related physical and biological processes. In this work, the processes of water immersion into silica nanoholes with different height/width aspect ratios (ϕ = 0.87, 1.92, 2.97, 4.01, 5.06) and different numbers of water molecules (N = 9986, 19972, 29958, 39944) were studied by molecular dynamics simulations. A comprehensive analysis has been conducted about the detailed process of water immersion and the influence of aspect ratios on water immersion rates. Five distinguishable stages were identified for the immersion process with all studied models. The results reveal that water can easily immerse into the silica nanoholes with larger ϕ and smaller N. The calculation also suggests that aspect ratios have a greater effect on water immersion rates for larger N numbers. The mechanism of the water immersion process is discussed in this work. We also propose a mathematical model to correlate the complete water immersion process for different aspect ratios.

Multipole mixing ratios in /sup 154/Gd

Energy Technology Data Exchange (ETDEWEB)

Chung, Won Mo; Song, Choong Sik; Joo, Koan Sik

1985-06-01

We have measured gamma-gamma angular correlations to determine the mixing ratios of several gamma transitions in /sup 154/Gd. The results are compared with those derived from the pairing-plus-quadrupole model and from the interacting boson model.

Live birth sex ratios and father's geographic origins in Jerusalem, 1964-1976.

Science.gov (United States)

Groeger, J; Opler, M; Kleinhaus, K; Perrin, M C; Calderon-Margalit, R; Manor, O; Paltiel, O; Conley, D; Harlap, S; Malaspina, D

2017-05-06

To examine whether ancestry influenced sex ratios of offspring in a birth cohort before parental antenatal sex selection influenced offspring sex. We measured the sex ratio as the percent of males according to countries of birth of paternal and maternal grandfathers in 91,459 live births from 1964 to 1976 in the Jerusalem Perinatal Study. Confidence limits (CI) were computed based on an expected sex ratio of 1.05, which is 51.4% male. Of all live births recorded, 51.4% were male. Relative to Jewish ancestry (51.4% males), significantly more males (1,761) were born to Muslim ancestry (54.5, 95% CI = 52.1-56.8, P = 0.01). Among the former, sex ratios were not significantly associated with paternal or maternal age, education, or offspring's birth order. Consistent with a preference for male offspring, the sex ratio decreased despite increasing numbers of births over the 13-year period. Sex ratios were not affected by maternal or paternal origins in North Africa or Europe. However, the offspring whose paternal grandfathers were born in Western Asia included fewer males than expected (50.7, 50.1-51.3, P = 0.02), whether the father was born abroad (50.7) or in Israel (50.8). This was observed for descendents of paternal grandfathers born in Lebanon (47.6), Turkey (49.9), Yemen & Aden (50.2), Iraq (50.5), Afghanistan (50.5), Syria (50.6), and Cyprus (50.7); but not for those from India (51.5) or Iran (51.9). The West Asian group showed the strongest decline in sex ratios with increasing paternal family size. A decreased sex ratio associated with ancestry in Western Asia is consistent with reduced ability to bear sons by a subset of Jewish men in the Jerusalem cohort. Lower sex ratios may be because of pregnancy stress, which may be higher in this subgroup. Alternatively, a degrading Y chromosome haplogroup or other genetic or epigenetic differences on male germ lines could affect birth ratios, such as differential exposure to an environmental agent, dietary

Effect of the Th-232/U-238 ratio on the conversion ratio of PWR's

International Nuclear Information System (INIS)

Correa, F.

1977-01-01

The conversion ratio, the consumption of natural uranium and separative work for current PWR lattice designs are studied as function of: the initial fraction of thorium in the fuel, the type of fuel recycling employed, and the growth rate of the system of reactors. The incentive to utilize thorium is maximum when: thorium is used together with fully enriched uranium (93%); if only uranium can be recycled; and the system of reactors is at equilibrium. Under these conditions, the comsumption of natural uranium and separative work are lower than the all-uranium-fuel case by 41% and 18%,respectively [pt

Ratio analysis specifics of the family dairies' financial statements

OpenAIRE

Mitrović Aleksandra; Knežević Snežana; Veličković Milica

2015-01-01

The subject of this paper is the evaluation of the financial analysis specifics of the dairy enterprises with a focus on the implementation of the ratio analysis of financial statements. The ratio analysis is a central part of financial analysis, since it is based on investigating the relationship between logically related items in the financial statements to assess the financial position of the observed enterprise and its earning capacity. Speaking about the reporting of financial performanc...

Lalinet status - station expansion and lidar ratio systematic measurements

Directory of Open Access Journals (Sweden)

Landulfo Eduardo

2018-01-01

Full Text Available LALINET is expanding regionally to guarantee spatial coverage over South and Central Americas. One of the network goals is to obtain a set of regional representative aerosol optical properties such as particle backscatter, extinction and lidar ratio. Given the North-South extension and influence of distinct airmass circulation patterns it is paramount to distinguish these optical parameters in order to gain better perfomance in radiation transfer models. A set of lidar ratio data is presented.

Idealized Compression Ratio for a Screw Briquetting Press

Directory of Open Access Journals (Sweden)

Peter Biath

2012-01-01

Full Text Available This paper deals with issues in determining the ideal compression ratio for a screw briquetting press. First, the principles of operation and a basic description of the main parts of a screw briquetting press are introduced. The next section describes the pressing space by means of 3D software. The pressing space was created using a Boolean subtract function. The final section of the paper measures the partial volumes of the pressing chamber in CATIA V5 by function of measuring. The measured values are substituted into the formula for the compression ratio, and the resulting evaluations are presented in the diagram in the conclusion of this paper.

Likelihood ratio decisions in memory: three implied regularities.

Science.gov (United States)

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.

Measurement of boron isotope ratios in groundwater studies

International Nuclear Information System (INIS)

Porteous, N.C.; Walsh, J.N.; Jarvis, K.E.

1995-01-01

Boron is present at low levels in groundwater and rainfall in the UK, ranging between 2 and 200 ng ml -1 . A sensitive technique has been developed using inductively coupled plasma mass spectrometry (ICP-MS) to measure boron isotope ratios at low concentrations with a precision (s r ) of between 0.1 and 0.2%. Samples were evaporated to increase elemental boron concentrations to 200 ng ml -1 and interfering matrix elements were removed by an adapted cation-exchange separation procedure. The validity of measuring boron isotopic ratios by ICP-MS at this concentration level is discussed in relation to the theoretical instrument precision attainable based on counting statistics. (author)

Sibling sex ratio of individuals diagnosed with autism spectrum disorder as children

DEFF Research Database (Denmark)

Mouridsen, Svend Erik; Rich, Bente; Isager, Torben

2010-01-01

AIM: To study the sex ratio (proportion of males) in siblings of individuals diagnosed with autism spectrum disorders (ASDs) as children. METHOD: In the current study, we extended previous studies dealing with the androgen theory of autism and examined sex ratios in the siblings of 326 individuals...... the Danish live-birth sex ratio over the same period (0.514, p=0.001). The sibling sex ratio was not associated with the IQ in the autistic probands. INTERPRETATION: Our findings suggest a potential indirect confirmation of the androgen theory of autism....

Lead isotope ratios of ancient Chinese and Japanese glasses

International Nuclear Information System (INIS)

Yamasaki, Kazuo; Murozumi, Masayo; Nakamura, Seiji; Yuasa, Mitsuaki; Watarai, Motohiko.

1980-01-01

Lead isotope ratios of 29 archaeological glass samples (5 samples excavated in China, 10 samples excavated in Japan, and 14 samples made in Japan) were determined by surface ionization mass spectrometry with a HITACHI RMU-6 spectrometer. Of these glass samples, 28 were made of high lead glass, and one, of alkali-lime glass. Glass samples were decomposed in a mixture of hydrofluoric and nitric acids, and lead was separated from other elements by extraction with dithizone-chloroform. The lead nitrate solution thus prepared (corresponding to 0.5 μg Pb) was loaded on the rhenium single filament. The coefficients of variation of the determined ratios, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, were 0.1 -- 0.3%. Among the glasses excavated in Japan, some samples of the Yayoi period (ca. 3 rd C. B.C. -- ca. 3 rd C. A.D.) contained a large amount of barium in addition to lead, and resembled closely Chinese pre-Han glasses not only in chemical compositions, but also in lead isotope ratios. This means that pre-Han glasses were brought to Japan and then re-cast into glass beads characteristic of Japan. The lead isotope ratios of the glasses were compared with those of Chinese (2 samples), Korean (2) and Japanese (17) galena orea, and it was found that 12 glass beads made in the 8th century at Nara and 2 fine glass tubes made at Saga in the 18 th -- 19 th centuries showed similar lead isotope ratios with those of the Japanese galena ores. Consequently it is considered that the Japanese galena ores were already used as one of raw materials at manufacturing of these glass beads in ancient centuries. (author)

Financial ratios in diagnostic radiology practices: variability and trends.

Science.gov (United States)

Hogan, Christopher; Sunshine, Jonathan H

2004-03-01

To evaluate variation in financial ratios for radiology practices nationwide and trends in these ratios and in payments. In 1999, the American College of Radiology surveyed radiology practices by mail. The final response rate was 66%. Weighting was used to make responses representative of all radiology practices in the United States. Self-reported financial ratios (payments, charges, accounts receivable turnover) were analyzed; 449 responses had usable data on these ratios. Comparison with results of a similar 1992 survey and combined analysis with Medicare data on billed charges provided information on trends. All measures of payment collections declined sharply from 1992 to 1999, with the gross collections rate (revenues as percentage of billed charges) decreasing from 71% to 55%. Average payment for a typical radiology service decreased approximately 4% in dollar terms or approximately 19% in inflation-adjusted terms. In 1999, nonmetropolitan practices appeared to fare better than others. Among insurers, Medicaid stood out as a low and slow payer, but neither managed care nor Medicare had a consistent effect on financial ratios. The gross collections rate varied substantially across geographic areas, as did, in an inverse pattern, the level of billed charges. One-quarter of practices had accounts receivable equal to 90 or more days of billings. The opposing geographic pattern of billed charges and gross collection rate suggests that geographic variation in the latter is driven more by variation in billed charges than by variation in payment levels. Radiologists saw a substantial decrease in the real (inflation-adjusted) value of payment per service during the 1990s. The large fraction of practices with accounts receivable of 90 or more days of billings-a level considered potentially imprudent by financial management advisors-suggests that many practices should improve financial management and that state prompt-payment laws have not had a substantial positive

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

Science.gov (United States)

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.

The Relevance of Employee-Related Ratios for Early Detection of Corporate Crises

Directory of Open Access Journals (Sweden)

Mario Situm

2014-12-01

Full Text Available The purpose of this study was to analyse whether employee-related ratios derived from accounts have incremental predictive power for the early detection of corporate crises and bankruptcies. Based on the literature reviewed, it can be seen that not much attention has been drawn to this task, indicating that further research is justified. For empirical research purposes, a database of Austrian companies was used for the time period 2003 to 2005 in order to develop multivariate linear discriminant functions for the classification of companies into the two states; bankrupt and non-bankrupt, and to detect the contribution of employee-related ratios in explaining why firms fail. Several ratios from prior research were used as potential predictors. In addition, other separate ratios were analysed, including employee-related figures. The results of the study show that while employee-related ratios cannot contribute to an improvement in the classification performance of prediction models, signs of these ratios within the discriminant functions did show the expected directions. Efficient usage of employees seems to play an important role in decreasing the probability of insolvency. Additionally, two employee-related ratios were found which can be used as proxies for the size of the firm. This had not been identified in prior studies for this factor.

Low Aspect-Ratio Wings for Wing-Ships

DEFF Research Database (Denmark)

Filippone, Antonino; Selig, M.

1998-01-01

Flying on ground poses technical and aerodynamical challenges. The requirements for compactness, efficiency, manouverability, off-design operation,open new areas of investigations in the fieldof aerodynamic analysis and design. A review ofthe characteristics of low-aspect ratio wings, in- and out...

Prognostic roles of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in ovarian cancer: a meta-analysis of retrospective studies.

Science.gov (United States)

Zhao, Zhe; Zhao, Xinrui; Lu, Jingjing; Xue, Jing; Liu, Peishu; Mao, Hongluan

2018-04-01

The systemic inflammatory response markers have been reported to be associated with the prognosis of various cancers. We conducted this meta-analysis of retrospective studies to evaluate and identify the prognostic impact of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) on ovarian cancer. PubMed, EMBASE, and China National Knowledge Infrastructure databases were included to search for eligible studies. The following terms were used: "neutrophil to lymphocyte ratio", "NLR", "platelet to lymphocyte ratio", "PLR", "ovarian cancer", "ovary cancer", "ovarian carcinoma", "ovary carcinoma", "ovarian neoplasm", "ovary neoplasm", "ovarian tumor", and "ovary tumor". The random-effects model was chosen to estimate the pooled HR with 95% CI. Heterogeneity between studies was assessed by Higgins I 2 value. The stability and heterogeneity of studies were analyzed by sensitivity analysis. Publication bias was examined by Egger's test and Begg's test with the funnel plots. 13 studies consisting of 3467 patients were considered for meta-analysis. We found that the high NLR had a poor prognostic impact on OS and PFS in ovarian cancer, with a pooled HR 1.70, 95% CI 1.35-2.15 and HR 1.77, 95% CI 1.48-2.12, respectively. Similarly, the results showed the high PLR adversely affected OS and PFS in ovarian cancer, with a pooled HR 2.05, 95% CI 1.70-2.48 and HR 1.85, 95% CI 1.53-2.25, respectively. In conclusion, we found that both NLR and PLR had an unfavorable impact on PFS and OS of patients with ovarian cancer. Our meta-analysis supported that NLR/PLR could be effective prognostic predictors of ovarian cancer.

Allowable pillar to diameter ratio for strategic petroleum reserve caverns.

Energy Technology Data Exchange (ETDEWEB)

Ehgartner, Brian L.; Park, Byoung Yoon

2011-05-01

This report compiles 3-D finite element analyses performed to evaluate the stability of Strategic Petroleum Reserve (SPR) caverns over multiple leach cycles. When oil is withdrawn from a cavern in salt using freshwater, the cavern enlarges. As a result, the pillar separating caverns in the SPR fields is reduced over time due to usage of the reserve. The enlarged cavern diameters and smaller pillars reduce underground stability. Advances in geomechanics modeling enable the allowable pillar to diameter ratio (P/D) to be defined. Prior to such modeling capabilities, the allowable P/D was established as 1.78 based on some very limited experience in other cavern fields. While appropriate for 1980, the ratio conservatively limits the allowable number of oil drawdowns and hence limits the overall utility and life of the SPR cavern field. Analyses from all four cavern fields are evaluated along with operating experience gained over the past 30 years to define a new P/D for the reserve. A new ratio of 1.0 is recommended. This ratio is applicable only to existing SPR caverns.

Effect of aspect ratio in free-swimming plunging flexible plates

Science.gov (United States)

Yeh, Peter; Alexeev, Alexander

2015-11-01

Using three dimensional fully-coupled fluid-structure interaction simulations, we investigate the free swimming of plunging elastic rectangular plates with aspect ratios ranging from 0.5 to 5 in a viscous fluid with Reynolds number 250. We find that maximum velocity occurs near the first natural frequency regardless of aspect ratio, while the maximum swimming economy occurs away from the first natural frequency and corresponds to a specific swimmer bending pattern characterized by reduced displacement of the swimmer's center of mass. Furthermore, we find that swimmers with wider span are both faster and more economical than narrow swimmers. These faster speeds are due to decreased drag for low aspect ratio plunging swimmers, which is in agreement with a recently proposed vortex-induced drag model that suggests that the smaller relative size of side vortices in low aspect ratio swimmers creates less drag per unit width. Our results are useful for the design of small autonomous micro-swimming devices and also provide insights on the physics of aquatic locomotion using oscillating fins.

Selective breeding for a behavioral trait changes digit ratio.

Directory of Open Access Journals (Sweden)

Reginia H Y Yan

Full Text Available The ratio of the length of the second digit (index finger divided by the fourth digit (ring finger tends to be lower in men than in women. This 2D:4D digit ratio is often used as a proxy for prenatal androgen exposure in studies of human health and behavior. For example, 2D:4D ratio is lower (i.e. more "masculinized" in both men and women of greater physical fitness and/or sporting ability. Lab mice have also shown variation in 2D:4D as a function of uterine environment, and mouse digit ratios seem also to correlate with behavioral traits, including daily activity levels. Selective breeding for increased rates of voluntary exercise (wheel running in four lines of mice has caused correlated increases in aerobic exercise capacity, circulating corticosterone level, and predatory aggression. Here, we show that this selection regime has also increased 2D:4D. This apparent "feminization" in mice is opposite to the relationship seen between 2D:4D and physical fitness in human beings. The present results are difficult to reconcile with the notion that 2D:4D is an effective proxy for prenatal androgen exposure; instead, it may more accurately reflect effects of glucocorticoids, or other factors that regulate any of many genes.

Evaluation of atmospheric particulate concentrations derived from analysis of ratio Thematic Mapper data

Science.gov (United States)

Carnahan, W. H.; Mausel, P. W.; Zhou, G. P.

1984-01-01

An approach for atmospheric particulate concentration evaluation above urban areas using ratio Thematic Mapper (TM) data is discussed. October 25, 1982 TM data over Chicago, IL are analyzed using TM band ratios of 1/2, 1/3, 1/4, 1/5, and 1/6 and particulate concentration estimates derived from TM ratios are tested over low reflective turbid water sites and highly reflective concrete highways. From analysis of the data it is evident that for water, the pattern of increasing particulate concentration is associated with decreasing ratio values in all band combinations used. Over concrete features, the TM band 1/4 ratio values follow the predicted pattern, while the TM band 1/6 has ratios which are reversed from anticipated values.

Peak power ratio generator

Science.gov (United States)

Moyer, R.D.

A peak power ratio generator is described for measuring, in combination with a conventional power meter, the peak power level of extremely narrow pulses in the gigahertz radio frequency bands. The present invention in a preferred embodiment utilizes a tunnel diode and a back diode combination in a detector circuit as the only high speed elements. The high speed tunnel diode provides a bistable signal and serves as a memory device of the input pulses for the remaining, slower components. A hybrid digital and analog loop maintains the peak power level of a reference channel at a known amount. Thus, by measuring the average power levels of the reference signal and the source signal, the peak power level of the source signal can be determined.

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

Science.gov (United States)

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.

How required reserve ratio affects distribution and velocity of money

Science.gov (United States)

Xi, Ning; Ding, Ning; Wang, Yougui

2005-11-01

In this paper the dependence of wealth distribution and the velocity of money on the required reserve ratio is examined based on a random transfer model of money and computer simulations. A fractional reserve banking system is introduced to the model where money creation can be achieved by bank loans and the monetary aggregate is determined by the monetary base and the required reserve ratio. It is shown that monetary wealth follows asymmetric Laplace distribution and latency time of money follows exponential distribution. The expression of monetary wealth distribution and that of the velocity of money in terms of the required reserve ratio are presented in a good agreement with simulation results.

Pharmacy technician-to-pharmacist ratios: a state-driven safety and quality decision.

Science.gov (United States)

Bess, D Todd; Carter, Jason; DeLoach, Lindsey; White, Carol L

2014-01-01

To discuss the policy of pharmacy technician-to-pharmacist ratios by comparing Florida as an example of legislative-led authority versus Tennessee as an example of board of pharmacy-led ruling. Over the past 2 years, the Florida legislature has debated the issue of pharmacy staffing ratios, initially leaving the Florida Board of Pharmacy with little authority to advocate for and enact safe technician staffing ratios. Anticipating this situation, the Tennessee Board of Pharmacy created rules to meet pharmacy staffing needs while protecting the authority of the pharmacist-in-charge and promoting patient safety. Before enacting rules, members of the board toured the state and talked about proposed rule changes with pharmacists. The final rule sets the pharmacy technician-to-pharmacist ratio at 2:1 but permits a 4:1 ratio based on public safety considerations and availability of at least two Certified Pharmacy Technicians. Pharmacists and leaders within the profession should conduct further research on appropriate and safe ratios of pharmacy technicians to pharmacists, with a focus on safety and quality of care.

Analytical investigation of different mathematical approaches utilizing manipulation of ratio spectra

Science.gov (United States)

Osman, Essam Eldin A.

2018-01-01

This work represents a comparative study of different approaches of manipulating ratio spectra, applied on a binary mixture of ciprofloxacin HCl and dexamethasone sodium phosphate co-formulated as ear drops. The proposed new spectrophotometric methods are: ratio difference spectrophotometric method (RDSM), amplitude center method (ACM), first derivative of the ratio spectra (1DD) and mean centering of ratio spectra (MCR). The proposed methods were checked using laboratory-prepared mixtures and were successfully applied for the analysis of pharmaceutical formulation containing the cited drugs. The proposed methods were validated according to the ICH guidelines. A comparative study was conducted between those methods regarding simplicity, limitations and sensitivity. The obtained results were statistically compared with those obtained from the reported HPLC method, showing no significant difference with respect to accuracy and precision.

Evaluation of Tp-Te Interval and Tp-Te/QT Ratio in Patients with Coronary Slow Flow Tp-Te/QT Ratio and Coronary Slow Flow.

Science.gov (United States)

Tenekecioglu, Erhan; Karaagac, Kemal; Yontar, Osman Can; Agca, Fahriye Vatansever; Ozluk, Ozlem Arican; Tutuncu, Ahmet; Arslan, Burhan; Yilmaz, Mustafa

2015-06-01

Coronary slow flow (CSF) phenomenon is described by angiographically normal coronary arteries with delayed opacification of the distal vasculature. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-Te) may correspond to the transmural dispersion of the repolarization and that increased Tp-Te interval and Tp-Te/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate the ventricular repolarization by using Tp-Te interval and Tp-Te/QT ratio in patients with CSF. This study included 50 CSF patients (40 male, mean age 48.6±12.5 years) and 40 control individuals (23 male, mean age 47.8±12.5 years). Tp-Te interval and Tp-Te/QT ratio were measured from the 12-lead electrocardiogram. These parameters were compared in groups. Baseline characteristics of the study groups were comparable. In electrocardiographic parameters analysis, QT and corrected QT were similar in CSF patients compared to the controls (357±35.2 vs 362±38.0 milliseconds and 419±25.8 vs 430±44.2 milliseconds, all p value >0.05). Tp-Te interval, Tp-Te/QT and Tp-Te/QTc ratio were significantly higher in CSF patients (85±13.7 vs 74±9.9 milliseconds and 0.24±0.03 vs 0.20±0.02 and 0.20±0.03 vs 0.17±0.02 all p value ratio are prolonged in patients with CSF.

Tracing lead pollution sources in abandoned mine areas using stable Pb isotope ratios.

Science.gov (United States)

Yoo, Eun-Jin; Lee, Jung-A; Park, Jae-Seon; Lee, Khanghyun; Lee, Won-Seok; Han, Jin-Seok; Choi, Jong-Woo

2014-02-01

This study focused on Pb isotope ratios of sediments in areas around an abandoned mine to determine if the ratios can be used as a source tracer. For pretreatment, sediment samples were dissolved with mixed acids, and a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS, Nu plasma II) was used to investigate the Pb isotopic composition of the samples. The measured isotope ratios were then corrected for instrumental mass fractionation by measuring the (203)Tl/(205)Tl ratio. Repeated measurements with the NIST SRM 981 reference material showed that the precision of all ratios was below 104 ppm (±2σ) for 50 ng/g. The isotope ratios ((207)Pb/(206)Pb) found were 0.85073 ± 0.0004~0.85373 ± 0.0003 for the main stream, while they were 0.83736 ± 0.0010 for the tributary and 0.84393 ± 0.0002 for the confluence. A binary mixing equation for isotope ratios showed that the contributions of mine lead to neighboring areas were up to 60%. Therefore, Pb isotope ratios can be a good source tracer for areas around abandoned mines.

Mass-to-light ratios of nearby groups of galaxies

CERN Document Server

Materne, J

1980-01-01

The application of a probability density function gives the possibility of determining groups of galaxies and membership probabilities of the galaxies in a reliable unbiased way. For the five nearest groups so defined, the mean mass-to-light ratio was derived using the concept of negative energy. These groups have a mass-to- light ratio of 16 M/sub (.)//L/sub (.)/. The probability function gives also the possibility of deriving masses of groups in a direct and independent way. (22 refs).

Synchronous Condenser Allocation for Improving System Short Circuit Ratio

DEFF Research Database (Denmark)

Jia, Jundi; Yang, Guangya; Nielsen, Arne Hejde

2018-01-01

With converter-based renewable energy sources increasingly integrated into power systems and conventional power plants gradually phased out, future power systems will experience reduced short circuit strength. The deployment of synchronous condensers can serve as a potential solution. This paper...... presents an optimal synchronous condenser allocation method for improving system short circuit ratio at converter point of common coupling using a modified short circuit analysis approach. The total cost of installing new synchronous condensers is minimized while the system short circuit ratios...

Hilar height ratio in normal Korea

International Nuclear Information System (INIS)

Yoo, Kyung Ho; Lee, Nam Joon; Seol, Hae Young; Chung, Kyoo Byung

1979-01-01

Hilar displacement is one of the significant sign of pulmonary volume change. The hilar height ratio (HHR) is a value that express the normal position of hilum in its hemithorax, and it is calculated by dividing the distance from the hilum to the lung apex by the distance from the hilum to the diaphragm. Displacement of one hilum is usually easy to detect but both are displaced in the same direction especially, recognition is more difficult. Knowledge of normal HHR allows evaluation of hilar positional change even when the relative hilar position are not altered. Normal chest PA views of 275 cases taken at Korea University Hospital during the period of April 1978 to Jun 1979 were analyzed. The right hilum is positioned in lower half of the right hemithorax, while the left hilum is situated in the upper half of left hemithorax. The difference of hilar ratio according to age group is slight, but there is significant difference between right-HHR and left-HHR. The value of right-HHR is 1.28 ± 0.14, the value of left-HHR is 0.88 ± 0.09.

Validation of the Rotation Ratios Method

International Nuclear Information System (INIS)

Foss, O.A.; Klaksvik, J.; Benum, P.; Anda, S.

2007-01-01

Background: The rotation ratios method describes rotations between pairs of sequential pelvic radiographs. The method seems promising but has not been validated. Purpose: To validate the accuracy of the rotation ratios method. Material and Methods: Known pelvic rotations between 165 radiographs obtained from five skeletal pelvises in an experimental material were compared with the corresponding calculated rotations to describe the accuracy of the method. The results from a clinical material of 262 pelvic radiographs from 46 patients defined the ranges of rotational differences compared. Repeated analyses, both on the experimental and the clinical material, were performed using the selected reference points to describe the robustness and the repeatability of the method. Results: The reference points were easy to identify and barely influenced by pelvic rotations. The mean differences between calculated and real pelvic rotations were 0.0 deg (SD 0.6) for vertical rotations and 0.1 deg (SD 0.7) for transversal rotations in the experimental material. The intra- and interobserver repeatability of the method was good. Conclusion: The accuracy of the method was reasonably high, and the method may prove to be clinically useful

Prediction of Microcystis Blooms Based on TN:TP Ratio and Lake Origin