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

E2,M1 Multipole mixing ratios in odd-mass nuclei, 59< or =A< or =149

International Nuclear Information System (INIS)

Krane, K.S.

1977-01-01

A survey is presented of the E2,M1 mxing ratios of gamma-ray transitions in odd-mass nuclei with 59< or =A< or =149. Angular distribution and correlation data from the literature are analyzed in terms of a consistent choice of the phase relationship between the E2 and M1 matrix elements. A set of recommended values of the mixing ratios is included, based on averages of results from various studies. The survey includes data available in the literature up to September 1976

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

Broad-range PCR: past, present, or future of bacteriology?

Science.gov (United States)

Renvoisé, A; Brossier, F; Sougakoff, W; Jarlier, V; Aubry, A

2013-08-01

PCR targeting the gene encoding 16S ribosomal RNA (commonly named broad-range PCR or 16S PCR) has been used for 20 years as a polyvalent tool to study prokaryotes. Broad-range PCR was first used as a taxonomic tool, then in clinical microbiology. We will describe the use of broad-range PCR in clinical microbiology. The first application was identification of bacterial strains obtained by culture but whose phenotypic or proteomic identification remained difficult or impossible. This changed bacterial taxonomy and allowed discovering many new species. The second application of broad-range PCR in clinical microbiology is the detection of bacterial DNA from clinical samples; we will review the clinical settings in which the technique proved useful (such as endocarditis) and those in which it did not (such as characterization of bacteria in ascites, in cirrhotic patients). This technique allowed identifying the etiological agents for several diseases, such as Whipple disease. This review is a synthesis of data concerning the applications, assets, and drawbacks of broad-range PCR in clinical microbiology. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

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

Science.gov (United States)

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

2015-05-01

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

Sex Ratio and Twinning in Women with Hyperemesis or Pre-eclampsia

DEFF Research Database (Denmark)

Basso, Olga; Olsen, Jørn

2001-01-01

We examined twinning and fetal gender in births of women with a hospital diagnosis of pre-eclampsia or hyperemesis. We also investigated sex ratio in infants whose mothers had had hyperemesis or pre-eclampsia in a different pregnancy. From all the hospitalized cases in Denmark between 1980 and 1996...... we extracted 6,227 births with hyperemesis and 24,764 with pre-eclampsia. Twins were more frequent in pregnancies with either condition. The male to female sex ratio was 1.04 (95%CI = 1.02-1.05) in the reference population, 0.87 (95% CI = 0.82-0.91) in births with hyperemesis, and 1.10 (95% CI = 1...

Backward running or absence of running from Creutz ratios

International Nuclear Information System (INIS)

Giedt, Joel; Weinberg, Evan

2011-01-01

We extract the running coupling based on Creutz ratios in SU(2) lattice gauge theory with two Dirac fermions in the adjoint representation. Depending on how the extrapolation to zero fermion mass is performed, either backward running or an absence of running is observed at strong bare coupling. This behavior is consistent with other findings which indicate that this theory has an infrared fixed point.

Highly Oriented Growth of Catalytically Active Zeolite ZSM‐5 Films with a Broad Range of Si/Al Ratios

OpenAIRE

Fu, Donglong; Schmidt, Joel E.; Ristanović, Zoran; Chowdhury, Abhishek Dutta; Meirer, Florian; Weckhuysen, Bert M.

2017-01-01

Abstract Highly b‐oriented zeolite ZSM‐5 films are critical for applications in catalysis and separations and may serve as models to study diffusion and catalytic properties in single zeolite channels. However, the introduction of catalytically active Al3+ usually disrupts the orientation of zeolite films. Herein, using structure‐directing agents with hydroxy groups, we demonstrate a new method to prepare highly b‐oriented zeolite ZSM‐5 films with a broad range of Si/Al ratios (Si/Al=45 to ∞)...

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.

Evaluation of the performance of Hy-Line Brown laying hens fed soybean or soybean-free diets using cage or free-range rearing systems.

Science.gov (United States)

Al-Ajeeli, M N; Leyva-Jimenez, H; Abdaljaleel, R A; Jameel, Y; Hashim, M M; Archer, G; Bailey, C A

2018-03-01

This study evaluated egg production and quality variables of caged and free-range Hy-Line Brown laying hens fed soybean meal (SBM) and soybean-meal-free (SBMF) diets. Hens were randomly assigned to the same 2 dietary treatments within 3 location blocks. SBM and SBMF diets with equivalent calculated nutrient content were prepared based on Hy-Line Brown rearing guidelines. The SBMF diets utilized cottonseed meal, corn distillers dried grains with solubles, corn gluten meal, and wheat middlings in place of dehulled soybean meal. The experiment was conducted between August 2015 and January of 2016 within the TAMU Poultry Research Center and data analyzed over 6 consecutive 28-day periods. Data were analyzed as a split-plot with rearing systems designated whole plots and diets designated as subplots. Hens reared in the free-range rearing system peaked a couple of wk later than those hens within the more conventional indoor caged system, and cumulative production data were considerably more variable for hens raised in the free-range environment. Cumulative egg production, feed per dozen eggs and feed conversion ratio (g feed/g egg) were 92 ± 1.23 and 86 ± 1.84%, 1.45 ± 0.02 and 1.89 ± 0.05 kg, and 2.14 ± 0.04 and 2.77 ± 0.08 (P free-range rearing systems. Cumulative egg weight, feed per dozen eggs, and feed conversion ratio were 59.9 ± 0.59 and 56.5 ± 0.60 g, 1.57 ± 0.04 and 1.77 ± 0.05 kg, and 2.24 ± 0.06 and 2.67 ± 0.08 kg (P  0.05). With respect to egg quality, there were no differences in cumulative albumen height, Haugh unit, or breaking strength, but there was a significant rearing system by diet interaction for shell thickness, with the free-range hens averaging 40.77 ± 0.19 and 39.86 ± 0.31 μm (P free-range production is more variable than traditional closed-house cage systems based on standard errors, and SBMF diets containing cottonseed meal can be used in both caged and free-range production systems without

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

Science.gov (United States)

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

2012-12-01

This study investigated effects of roasted or extruded oilseed supplementation ranging in n-6/n-3 ratios from 0.3 to 5.0 on the fatty acid composition and expression of delta-5 desaturase (Δ5d) and Δ6-desaturase (Δ6d) protein in commercial steer cheek (m. masseter) and diaphragm (pars costalis diaphragmatis) muscles. In general, the n-6/n-3 ratio of the diet had a subsequent effect on the muscle n-6/n-3 ratio (P muscle 18:2n-6 and 18:3n-3 content relating to proportion of dietary soya bean and linseed (P muscle the Δ5d protein expression had a stronger association with the desaturase products rather than the precursors. The relationship between Δ5d protein expression and the muscle LC n-6/n-3 ratio was negative in both muscles (P muscle 18:2n-6 and 18:3n-3 deposition, whereas the Δ5d and Δ6d protein expression had some influence on the polar lipid LC-PUFA profile. Results reaffirm that processed oilseeds can be used to increase the proportion of fatty acids potentially beneficial for human health, by influencing the formation of LC-PUFA and reducing the n-6/n-3 ratio.

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

Science.gov (United States)

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

2017-05-01

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

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.

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

Science.gov (United States)

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

2018-01-01

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

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

Science.gov (United States)

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

2018-03-01

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

Use of a range scaling method to determine alanine/water stopping power ratios

International Nuclear Information System (INIS)

McEwen, M.R.; Sephton, J.P.; Sharpe, P.H.G.; Shipley, D.R.

2003-01-01

A phantom composed of alanine dosimeter material has been constructed and depth-dose measurements made in a 10 MeV electron beam. The results have demonstrated the feasibility of using relative depth-dose measurements to determine stopping power ratios in materials of dosimetric interest. Experimental stopping power ratios for alanine dosimeter material and water agreed with the data of ICRU Report 37 within the uncertainty of the experiment (±1.2% at a 95% confidence level)

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)

Measurement of the ratio of charged current neutrino cross sections on neutrons and protons in the energy range 1-10 GeV

International Nuclear Information System (INIS)

Lerche, W.; Pohl, M.; Schultze, K.; Derange, B.; Francois, T.; Van Dam, P.; Jaffre, M.; Longuemare, C.; Pascaud, C.; Calimani, E.; Ciampolillo, S.; Mattioli, F.

1978-01-01

The charged current cross-section ratio R = sigma(γ+n)/sigma(γ+p), averaged over the energy range, 1-10 GeV, is determined by two independent methods. The combined value is R = 2.08+-0.15. Semi-inclusive proton production rates on both proton and neutron targets are presented. Event rates of exclusive channels on the proton target are also given. (Auth.)

Underwater Ranging

OpenAIRE

S. P. Gaba

1984-01-01

The paper deals with underwater laser ranging system, its principle of operation and maximum depth capability. The sources of external noise and methods to improve signal-to-noise ratio are also discussed.

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.

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.

The Effect of Ratio of Contraction to Relaxation Durations in PNF Exercises on the Muscle Strength and Range of Motion of Hip Joint

Directory of Open Access Journals (Sweden)

Hossein Rashedi

2015-09-01

Full Text Available Objective: The aim of the present study was to compare the effect of ratios of contraction- Relaxation on the muscle strength and range of motion of hip joint in PNF exercises. Methods: Thirty nine nonathletic male students (Mean±SD; age, 13±1.2 years; body mass, 55±9.8 kg were assigned .Three groups designated as I, II and III groups. The ratios of contraction to relaxation periods for groups were 1, 2 and 3 respectively. Training program included three sessions per week (CR-PNF for 6 weeks. Measurements of hip extensors muscles stretch and strength were performed at the beginning and at the end of training using an inclinometer (during leg raise test and dynamometer. Data were analyzed using dependent samples t-test and one-way ANOVA. Results: The results of the present study showed significant increases in hip extensor muscles flexibility and strength for three groups. This increase the in the strength in group I equaled 6 kg, in group II 4 kg and in group III 7 kg. The amount of increase in the hip extensor muscles flexibility in group I, II and II were 15, 8 and 12 degrees, respectively. The increase in these two variables was significant and similar in all three groups. Conclusion: Different contraction to relaxation ratio normally, 0.5, 1 and 2, did not show any meaningful differences on hip extensor muscular strength and hip range of motion.

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

Science.gov (United States)

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

2011-01-01

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

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.

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.

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

Science.gov (United States)

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

1974-01-01

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

Precise Range Determination Using Laser Ranging Data of LAGEOS

Directory of Open Access Journals (Sweden)

Kwang-Ryul Kim

1993-12-01

Full Text Available Satellite laser ranging observation of LAGEOS ¥± has been performed using the SLR System at Sheshan Laser Ranging Station, Shanghai Observatory. And we obtained 1,838 observational points The observed range data is corrected by means of system delay correction using ground target observation, atmospheric refraction delay correction, offset correction, general relativistic correction and tide correction including solid tide, polar tide and ocean tide. As a result, the determined range delay mean value is 19.12m and the mean internal accuracy by means of polynomial fitting and least square method is ¡¾7cm. Corrected observational points are 1,340 and noise ratio to total observational points is 27.1%

Effect of genotype and transport on tonic immobility and heterophil/lymphocyte ratio in two local Italian breeds and Isa Brown hens kept under free-range conditions

Directory of Open Access Journals (Sweden)

Michele De Marco

2013-10-01

Full Text Available This study was undertaken to investigate the effect of transport and genotype on the welfare and fear response of laying hens through a comparison of three breeds reared in free-range conditions: a commercial strain, the Isa Brown (IBh, and two local chicken breeds, the Bionda Piemontese (BPh and the Bianca di Saluzzo (BSh. After a journey of 67 km (75 min from the farmhouse of origin to the experimental station, ninety hens, divided according to breed, were free-range reared for two months. Body weight (BW, tonic immobility (TI, red and white blood cells, heterophil to lymphocyte (H/L ratio and α1-acid glycoprotein (AGP were assessed at four different sampling times: at the farmhouse of origin (T1, at 1 day (T2, 15 days (T3 and at 2 months (T4 after arrival at the experimental station. No statistical differences were found between the four sampling times for BW, total red and white blood parameters. cells or for AGP. An increase in the H/L ratio (P<0.05 was recorded at time T2 for IBh and BSh, compared to BPh (P<0.05. TI was significantly higher (P<0.05 for the local breeds, BPh and BSh, than for the commercial strain IBh. The results of this study suggest that genetic and adaptive differences can affect both, physiological and ethological parameters.

Challenges in miniaturized automotive long-range lidar system design

Science.gov (United States)

Fersch, Thomas; Weigel, Robert; Koelpin, Alexander

2017-05-01

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

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.

Can Coronene and/or Benzo(a)pyrene/Coronene ratio act as unique markers for vehicle emission?

International Nuclear Information System (INIS)

Shen, Guofeng; Chen, Yuanchen; Wei, Siye; Fu, Xiaofang; Ding, Aijun; Wu, Haisuo; Tao, Shu

2014-01-01

Coronene is a high molecular weight polycyclic aromatic hydrocarbon with seven aromatic rings. It, more specifically a lower ratio of Benzo[a]pyrene to Coronone (BaP/COR), is suggested as a marker for vehicle emission. In the present study, emissions of Coronene were measured from residential combustions of wood, crop straw, and pellets. The detection of COR in non-vehicle emission sources, and comparable BaP/COR ratios between the solid fuel combustion and vehicle emissions indicated that the generality of COR or the BaP/COR ratio as markers for the vehicle emission would be questionable, especially for the area where solid fuel combustion dominated the PAHs emission. Highlights: • Coronene alone is not a unique marker for vehicle emission. • The specific ratio, BaP/Coronene, could be very high for gasoline emission. • The use of a specific ratio, BaP/Coronene, as a marker is debatable. -- Coronene alone is not a unique tracer for vehicle emission and the use of specific Benzo[a]pyrene to Coronene ratio needs more evaluation studies

System and method for high precision isotope ratio destructive analysis

Science.gov (United States)

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

2013-07-02

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

Sterilization of melon flies: mating competitiveness after treatment with tepa or gamma irradiation and ratios of treated to untreated flies producing population suppression

International Nuclear Information System (INIS)

Ashraf, M.; Keiser, I.; Harris, E.J.

1976-01-01

Male melon flies, Dacus cucurbitae Coquillett, treated with a single dose of the chemosterilant tepa (tris(l-aziridinyl) phosphine oxide), or with gamma irradiation, either single or fractionated doses, did not differ significantly in sexual competitiveness as determined by percentage hatch of eggs. Mating competitiveness of males treated by either method ranged from 53 to 66 percent of that of untreated males. In another study, melon flies (males and females) sterilized with 0.0125 percent tepa, the threshold dose for both sexes, completely suppressed a population when the ratio was 16:16:1:1 (sterile males-sterile females-untreated males-untreated females) as determined by no egg hatch

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.

RATIO_TOOL - SOFTWARE FOR COMPUTING IMAGE RATIOS

Science.gov (United States)

Yates, G. L.

1994-01-01

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

Ratio dependence in small number discrimination is affected by the experimental procedure

Directory of Open Access Journals (Sweden)

Christian eAgrillo

2015-10-01

Full Text Available Adults, infants and some non-human animals share an approximate number system (ANS to estimate numerical quantities, and are supposed to share a second, ‘object-tracking’, system (OTS that supports the precise representation of a small number of items (up to 3 or 4. In relative numerosity judgments, accuracy depends on the ratio of the two numerosities (Weber’s Law, for numerosities > 4 (the typical ANS range, while for numerosities ≤ 4 (OTS range there is usually no ratio effect. However, recent studies have found evidence for ratio effects for small numerosities, challenging the idea that the OTS might be involved for small number discrimination. Here we tested the hypothesis that the lack of ratio effect in the numbers 1-4 is largely dependent on the type of stimulus presentation.We investigated relative numerosity judgments in college students using three different procedures: a simultaneous presentation of intermingled and separate groups of dots in separate experiments, and a further experiment with sequential presentation. As predicted, in the large number range, ratio dependence was observed in all tasks. By contrast, in the small number range, ratio insensitivity was found in one task (sequential presentation. In a fourth experiment, we showed that the presence of intermingled distractors elicited a ratio effect, while easily distinguishable distractors did not. As the different ratio sensitivity for small and large numbers has been often interpreted in terms of the activation of the OTS and ANS, our results suggest that numbers 1-4 may be represented by both numerical systems and that the experimental context, such as the presence/absence of task-irrelevant items in the visual field, would determine which system is activated.

Consumers' motivational associations favoring free-range meat or less meat

NARCIS (Netherlands)

de Boer, J.; Boersema, J.J.; Aiking, H.

2009-01-01

The present paper analyzed the motivational orientations of consumers who choose to eat (1) small portions of meat or (2) ethically distinctive meat, such as free-range meat, in relation to the motivational orientations of their opposites. Going beyond the conventional approach to consumer behavior,

Golden Ratio

Indian Academy of Sciences (India)

Keywords. Fibonacci numbers, golden ratio, Sanskrit prosody, solar panel. Abstract. Our attraction to another body increases if the body is symmetricaland in proportion. If a face or a structure is in proportion,we are more likely to notice it and find it beautiful.The universal ratio of beauty is the 'Golden Ratio', found inmany ...

Golden Ratio

Indian Academy of Sciences (India)

Our attraction to another body increases if the body is symmetricaland in proportion. If a face or a structure is in proportion,we are more likely to notice it and find it beautiful.The universal ratio of beauty is the 'Golden Ratio', found inmany structures. This ratio comes from Fibonacci numbers.In this article, we explore this ...

Multilayered samples reconstructed by measuring Kα/Kβ or Lα/Lβ X-ray intensity ratios by EDXRF

Science.gov (United States)

Cesareo, Roberto; de Assis, Joaquim T.; Roldán, Clodoaldo; Bustamante, Angel D.; Brunetti, Antonio; Schiavon, Nick

2013-10-01

In this paper a general method based on energy-dispersive X-ray fluorescence (EDXRF) analysis has been tested to assess its possible use as a tool to reconstruct the structure and determine the thickness of two and/or multi-layered materials. The method utilizes the X-ray intensity ratios of Kα/Kβ or Lα/Lβ peaks (or the ratio of these peaks) for selected elements present in multi-layered objects of various materials (Au alloys, gilded Cu, gilded Ag, gilded Pb, Ag-Au Tumbaga, stone surfaces with protective treatments, Zn or Nickel plating on metals). Results show that, in the case of multi-layered samples, a correct calculation of the peak ratio (Kα /Kβ and/or Lα/Lβ) of relevant elements from energy-dispersive X-ray fluorescence spectra, can provide important information in assessing the exact location of each layer and for calculating its thickness. The methodological approach shown may have important applications not only in materials science but also when dealing with the conservation and restoration of multi-layered cultural heritage objects where the use of a Non-Destructive techniques to determine slight chemical and thickness variations in the layered structure is often of paramount importance to achieve the best results.

Golden Ratio

Indian Academy of Sciences (India)

Our attraction to another body increases if the body is sym- metrical and in proportion. If a face or a structure is in pro- portion, we are more likely to notice it and find it beautiful. The universal ratio of beauty is the 'Golden Ratio', found in many structures. This ratio comes from Fibonacci numbers. In this article, we explore this ...

Meal composition and plasma amino acid ratios: Effect of various proteins or carbohydrates, and of various protein concentrations

Science.gov (United States)

Yokogoshi, Hidehiko; Wurtman, Richard J.

1986-01-01

The effects of meals containing various proteins and carbohydrates, and of those containing various proportions of protein (0 percent to 20 percent of a meal, by weight) or of carbohydrate (0 percent to 75 percent), on plasma levels of certain large neutral amino acids (LNAA) in rats previously fasted for 19 hours were examined. Also the plasma tryptophan ratios (the ratio of the plasma trytophan concentration to the summed concentrations of the other large neutral amino acids) and other plasma amino acid ratios were calculated. (The plasma tryptophan ratio has been shown to determine brain tryptophan levels and, thereby, to affect the synthesis and release of the neurotransmitter serotonin). A meal containing 70 percent to 75 percent of an insulin-secreting carbohydrate (dextrose or dextrin) increased plasma insulin levels and the tryptophan ratio; those containing 0 percent or 25 percent carbohydrate failed to do so. Addition of as little as 5 percent casein to a 70 percent carbohydrate meal fully blocked the increase in the plasma tryptophan ratio without affecting the secretion of insulin - probably by contributing much larger quantities of the other LNAA than of tryptophan to the blood. Dietary proteins differed in their ability to suppress the carbohydrate-induced rise in the plasma tryptophan ratio. Addition of 10 percent casein, peanut meal, or gelatin fully blocked this increase, but lactalbumin failed to do so, and egg white did so only partially. (Consumption of the 10 percent gelatin meal also produced a major reduction in the plasma tyrosine ratio, and may thereby have affected brain tyrosine levels and catecholamine synthesis.) These observations suggest that serotonin-releasing neurons in brains of fasted rats are capable of distinguishing (by their metabolic effects) between meals poor in protein but rich in carbohydrates that elicit insulin secretion, and all other meals. The changes in brain serotonin caused by carbohydrate-rich, protein

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

Highly Oriented Growth of Catalytically Active Zeolite ZSM-5 Films with a Broad Range of Si/Al Ratios.

Science.gov (United States)

Fu, Donglong; Schmidt, Joel E; Ristanović, Zoran; Chowdhury, Abhishek Dutta; Meirer, Florian; Weckhuysen, Bert M

2017-09-04

Highly b-oriented zeolite ZSM-5 films are critical for applications in catalysis and separations and may serve as models to study diffusion and catalytic properties in single zeolite channels. However, the introduction of catalytically active Al 3+ usually disrupts the orientation of zeolite films. Herein, using structure-directing agents with hydroxy groups, we demonstrate a new method to prepare highly b-oriented zeolite ZSM-5 films with a broad range of Si/Al ratios (Si/Al=45 to ∞). Fluorescence micro-(spectro)scopy was used to monitor misoriented microstructures, which are invisible to X-ray diffraction, and show Al 3+ framework incorporation and illustrate the differences between misoriented and b-oriented films. The methanol-to-hydrocarbons process was studied by operando UV/Vis diffuse reflectance micro-spectroscopy with on-line mass spectrometry, showing that the b-oriented zeolite ZSM-5 films are active and stable under realistic process conditions. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

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

Practical Guidance for Conducting Mediation Analysis With Multiple Mediators Using Inverse Odds Ratio Weighting

OpenAIRE

Nguyen, Quynh C.; Osypuk, Theresa L.; Schmidt, Nicole M.; Glymour, M. Maria; Tchetgen Tchetgen, Eric J.

2015-01-01

Despite the recent flourishing of mediation analysis techniques, many modern approaches are difficult to implement or applicable to only a restricted range of regression models. This report provides practical guidance for implementing a new technique utilizing inverse odds ratio weighting (IORW) to estimate natural direct and indirect effects for mediation analyses. IORW takes advantage of the odds ratio's invariance property and condenses information on the odds ratio for the relationship be...

Chinese tallow trees (Triadica sebifera) from the invasive range outperform those from the native range with an active soil community or phosphorus fertilization.

Science.gov (United States)

Zhang, Ling; Zhang, Yaojun; Wang, Hong; Zou, Jianwen; Siemann, Evan

2013-01-01

Two mechanisms that have been proposed to explain success of invasive plants are unusual biotic interactions, such as enemy release or enhanced mutualisms, and increased resource availability. However, while these mechanisms are usually considered separately, both may be involved in successful invasions. Biotic interactions may be positive or negative and may interact with nutritional resources in determining invasion success. In addition, the effects of different nutrients on invasions may vary. Finally, genetic variation in traits between populations located in introduced versus native ranges may be important for biotic interactions and/or resource use. Here, we investigated the roles of soil biota, resource availability, and plant genetic variation using seedlings of Triadica sebifera in an experiment in the native range (China). We manipulated nitrogen (control or 4 g/m(2)), phosphorus (control or 0.5 g/m(2)), soil biota (untreated or sterilized field soil), and plant origin (4 populations from the invasive range, 4 populations from the native range) in a full factorial experiment. Phosphorus addition increased root, stem, and leaf masses. Leaf mass and height growth depended on population origin and soil sterilization. Invasive populations had higher leaf mass and growth rates than native populations did in fresh soil but they had lower, comparable leaf mass and growth rates in sterilized soil. Invasive populations had higher growth rates with phosphorus addition but native ones did not. Soil sterilization decreased specific leaf area in both native and exotic populations. Negative effects of soil sterilization suggest that soil pathogens may not be as important as soil mutualists for T. sebifera performance. Moreover, interactive effects of sterilization and origin suggest that invasive T. sebifera may have evolved more beneficial relationships with the soil biota. Overall, seedlings from the invasive range outperformed those from the native range, however

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)

Higher levels of albuminuria within the normal range predict incident hypertension.

Science.gov (United States)

Forman, John P; Fisher, Naomi D L; Schopick, Emily L; Curhan, Gary C

2008-10-01

Higher levels of albumin excretion within the normal range are associated with cardiovascular disease in high-risk individuals. Whether incremental increases in urinary albumin excretion, even within the normal range, are associated with the development of hypertension in low-risk individuals is unknown. This study included 1065 postmenopausal women from the first Nurses' Health Study and 1114 premenopausal women from the second Nurses' Health Study who had an albumin/creatinine ratio who did not have diabetes or hypertension. Among the older women, 271 incident cases of hypertension occurred during 4 yr of follow-up, and among the younger women, 296 incident cases of hypertension occurred during 8 yr of follow-up. Cox proportional hazards regression was used to examine prospectively the association between the albumin/creatinine ratio and incident hypertension after adjustment for age, body mass index, estimated GFR, baseline BP, physical activity, smoking, and family history of hypertension. Participants who had an albumin/creatinine ratio in the highest quartile (4.34 to 24.17 mg/g for older women and 3.68 to 23.84 mg/g for younger women) were more likely to develop hypertension than those who had an albumin/creatinine ratio in the lowest quartile (hazard ratio 1.76 [95% confidence interval 1.21 to 2.56] and hazard ratio 1.35 [95% confidence interval 0.97 to 1.91] for older and younger women, respectively). Higher albumin/creatinine ratios, even within the normal range, are independently associated with increased risk for development of hypertension among women without diabetes. The definition of normal albumin excretion should be reevaluated.

Assets Held for Sale and Discontinued Operations – Evaluation of Liquidity – Determination of Ratio – or Necessity of Adjustment?

Directory of Open Access Journals (Sweden)

Grazyna Voss

2015-03-01

Full Text Available The change in the use of an asset results from economic conditions and requires that a company revalue the asset and adjusts its value by costs of sale or liquidation. The current value of the asset determined in that way influences the financial result of the company and enables the movement of value from non-current assets to current assets. This change has an impact on the evaluation of financial situation and financial ratios.The aim of this article is to describe principles of measurement and presentation of assets held for sale and application of financial analysis in order to assess risks by potential investors. The purpose of this work constitutes part of a wide-ranging discussion on the directions of changes in financial reporting and principles of effective investing.

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

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.

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.

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

Science.gov (United States)

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

2017-12-01

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

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.

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.

Real-time high dynamic range laser scanning microscopy

Science.gov (United States)

Vinegoni, C.; Leon Swisher, C.; Fumene Feruglio, P.; Giedt, R. J.; Rousso, D. L.; Stapleton, S.; Weissleder, R.

2016-04-01

In conventional confocal/multiphoton fluorescence microscopy, images are typically acquired under ideal settings and after extensive optimization of parameters for a given structure or feature, often resulting in information loss from other image attributes. To overcome the problem of selective data display, we developed a new method that extends the imaging dynamic range in optical microscopy and improves the signal-to-noise ratio. Here we demonstrate how real-time and sequential high dynamic range microscopy facilitates automated three-dimensional neural segmentation. We address reconstruction and segmentation performance on samples with different size, anatomy and complexity. Finally, in vivo real-time high dynamic range imaging is also demonstrated, making the technique particularly relevant for longitudinal imaging in the presence of physiological motion and/or for quantification of in vivo fast tracer kinetics during functional imaging.

Oxygen isotopic ratios in quartz as an indicator of provenance of dust

International Nuclear Information System (INIS)

Jackson, M.L.

1977-01-01

Quartz was isolated in the long range aerosol size range (fine silt, 1-10 μm in diameter) from atmospheric aerosols, wind-erosive soils, soil silts, shales, and Pacific pelagic sediments of the Northern and Southern Hemispheres, to trace their provenance or origin, as part of a study of dust mineral sequestering of 137 Cs and other products of nuclear fission. The oxygen isotopic ratio ( 18 O/ 16 O) was determined by mass spectrometry. The provenance has been established for this fine silt fraction which reflects the relative proportion of two classes of quartz source: (a) weathering of igneous and metamorphic rocks (high temperature origin and low 18 O/ 16 O ratio) and (b) of quartz crystallized in cherts and overgrowths (low temperature origin and high 18 O/ 16 O ratio). This quartz mixing ratio is a basic model or paradigm. Analyses of present day atmospheric aerosols and eolian-derived soils, Pacific pelagic sediments, and now-raised Phanerozoic marine sediments show that the Northern and Southern Hemispheres have separate large-scale reservoirs of the fine grain sizes that contribute to aerosol dusts. These can be identified by distinctive values of 18 O/ 16 O ratios of the quartz therein. The difference in quartz delta 18 O value in parts per thousand per ml ( 0 / 00 of about 12 +- 2 0 / 00 in Southern Hemisphere mixed detrital sediments and about 19 +- 2 0 / 00 in those of the Northern Hemisphere (for constant size, the 1-10 μm size fraction) results from the presence of a considerably larger proportion of quartz having low-temperature origin and higher delta 18 O values (chert, silica overgrowths, etc.) in the Northern Hemisphere reservoirs. The early paleoclimatic and paleogeochemical differences remain the control of the North-South Hemisphere difference in delta 18 O values in long-range aerosol sized quartz

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

Science.gov (United States)

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

2016-09-26

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

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

Science.gov (United States)

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

2016-09-01

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

Optimization of E-DCH channel power ratios to maximize link level efficiency

DEFF Research Database (Denmark)

Zarco, Carlos Ruben Delgado; Malone, Jaime Tito; Wigard, Jeroen

2006-01-01

For the WCDMA/HSUPA concept, a key to ensuring high spectral efficiency is to correctly adjust the transmission power ratios among the data and control channels. This paper provides optimal values for the power ratio between the Enhanced-Dedicated Physical Data Channel (E-DPDCH) and the Dedicated...... rate (typical values ranging from 8.1 to 9.9 dB) and the RSN target (maintaining or decreasing their value as the target increases). These results show that it is more link efficient to increase the DPCCH transmission power with the bit rate (and the E-DPDCH's by applying the power ratio) than...... to maintain a constant DPCCH transmission power and just increase the EDPDCH to DPCCH power ratio....

Metabolic control by sirtuins and other enzymes that sense NAD(+), NADH, or their ratio

DEFF Research Database (Denmark)

Anderson, Kristin A; Madsen, Andreas S; Olsen, Christian A

2017-01-01

NAD(+) is a dinucleotide cofactor with the potential to accept electrons in a variety of cellular reduction-oxidation (redox) reactions. In its reduced form, NADH is a ubiquitous cellular electron donor. NAD(+), NADH, and the NAD(+)/NADH ratio have long been known to control the activity of several...... oxidoreductase enzymes. More recently, enzymes outside those participating directly in redox control have been identified that sense these dinucleotides, including the sirtuin family of NAD(+)-dependent protein deacylases. In this review, we highlight examples of non-redox enzymes that are controlled by NAD......(+), NADH, or NAD(+)/NADH. In particular, we focus on the sirtuin family and assess the current evidence that the sirtuin enzymes sense these dinucleotides and discuss the biological conditions under which this might occur; we conclude that sirtuins sense NAD(+), but neither NADH nor the ratio. Finally, we...

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.

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

Science.gov (United States)

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

2018-01-01

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

Clinical implications of free-to-total immunoreactive prostate-specific antigen ratios

NARCIS (Netherlands)

Wymenga, LFA; Duisterwinkel, FJ; Groenier, K; Visser-van Brummen, P; Marrink, J; Mensink, HJA

Objective: A study was performed to evaluate the free-to-total prostate-specific antigen (PSA) ratio for discriminating benign prostatic hyperplasia (BPH) or prostate cancer in the intermediate PSA range (2.0-10.0 mu g/l) in patients referred for prostate evaluation. In addition, the relationship of

Sharpening Sharpe Ratios

OpenAIRE

William N. Goetzmann; Jonathan E. Ingersoll Jr.; Matthew I. Spiegel; Ivo Welch

2002-01-01

It is now well known that the Sharpe ratio and other related reward-to-risk measures may be manipulated with option-like strategies. In this paper we derive the general conditions for achieving the maximum expected Sharpe ratio. We derive static rules for achieving the maximum Sharpe ratio with two or more options, as well as a continuum of derivative contracts. The optimal strategy has a truncated right tail and a fat left tail. We also derive dynamic rules for increasing the Sharpe ratio. O...

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

Science.gov (United States)

Liu, Jianxing; Zhang, Yihui

2018-01-31

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

Soil Compressibility Models for a Wide Stress Range

KAUST Repository

Chong, Song-Hun

2016-03-03

Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low and high stress levels; all updated models involve four parameters. Compiled consolidation data for remolded and natural clays are used to test the models and to develop correlations between model parameters and index properties. Models can adequately fit soil compression data for a wide range of stresses and soil types; in particular, models that involve the power of the stress σ\\'β display higher flexibility to capture the brittle response of some natural soils. The use of a single continuous function avoids numerical discontinuities or the need for ad hoc procedures to determine the yield stress. The tangent stiffness-readily computed for all models-should not be mistaken for the small-strain constant-fabric stiffness. © 2016 American Society of Civil Engineers.

Out-of-range INR values and outcomes among new warfarin patients with non-valvular atrial fibrillation.

Science.gov (United States)

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

2015-02-01

Although efficacious in stroke prevention in non-valvular atrial fibrillation, many warfarin patients are sub-optimally managed. To evaluate the association of international normalized ratio control and clinical outcomes among new warfarin patients with non-valvular atrial fibrillation. Adult non-valvular atrial fibrillation patients (≥18 years) initiating warfarin treatment were selected from the US Veterans Health Administration dataset between 10/2007 and 9/2012. Valid international normalized ratio values were examined from the warfarin initiation date through the earlier of the first clinical outcome, end of warfarin exposure or death. Each patient contributed multiple in-range and out-of-range time periods. The relative risk ratios of clinical outcomes associated with international normalized ratio control were estimated. 34,346 patients were included for analysis. During the warfarin exposure period, the incidence of events per 100 person-years was highest when patients had international normalized ratio 3, patients had significantly increased risk of major bleeding (relative risk ratio: 1.5; 95 % confidence interval 1.2-2.0). In a Veterans Health Administration non-valvular atrial fibrillation population, exposure to out-of-range international normalized ratio values was associated with significantly increased risk of adverse clinical outcomes.

Abundance ratios in dwarf elliptical galaxies

Science.gov (United States)

Şen, Ş.; Peletier, R. F.; Boselli, A.; den Brok, M.; Falcón-Barroso, J.; Hensler, G.; Janz, J.; Laurikainen, E.; Lisker, T.; Mentz, J. J.; Paudel, S.; Salo, H.; Sybilska, A.; Toloba, E.; van de Ven, G.; Vazdekis, A.; Yesilyaprak, C.

2018-04-01

We determine abundance ratios of 37 dwarf ellipticals (dEs) in the nearby Virgo cluster. This sample is representative of the early-type population of galaxies in the absolute magnitude range -19.0 originate from late-type dwarfs or small spirals. Na-yields appear to be very metal-dependent, in agreement with studies of giant ellipticals, probably due to the large dependence on the neutron-excess in stars. We conclude that dEs have undergone a considerable amount of chemical evolution, they are therefore not uniformly old, but have extended SFH, similar to many of the Local Group galaxies.

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.

MEMS variable capacitance devices utilizing the substrate: I. Novel devices with a customizable tuning range

KAUST Repository

Elshurafa, Amro M.; El-Masry, Ezz I.

2010-01-01

, customizable, tuning ranges and/or ratios. The proposed structures can provide theoretical tuning ranges anywhere from 4.9 to 35 and from 3.4 to 26 respectively with a simple, yet effective, layout modification as opposed to the previously reported devices

Thickness measurement of multilayered samples by Kα/Kβ or Lα/Lβ X-ray ratios

Energy Technology Data Exchange (ETDEWEB)

Cesareo, Roberto; Brunetti, Antonio, E-mail: roberto.cesareo@gmail.com, E-mail: brunetti@uniss.it [Universita di Sassari (UNISS), Sassari, (Italy); Assis, Joaquim T. de, E-mail: rcbarros@pq.cnpq.br [Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ (Brazil)

2013-07-01

Objects composed of two or more layers are relatively common among industrial and electronic materials, works of art and common tools. For example plated objects (with zinc, nickel, silver, gold) are composed of two or three layers, a painting is generally composed of several layers, a decorated vase is composed of two or three layers, just as a stone, marble or bronze covered with a protective layer. In this paper a general method and some results are described to reconstruct structure and to determine thicknesses of multilayered material, when energy dispersive X-ray fluorescence is employed to analyze the material: the X-ray ratios of Kα/Kβ and Lα/Lβ for elements present in the multilayered samples are employed. (author)

Thickness measurement of multilayered samples by Kα/Kβ or Lα/Lβ X-ray ratios

International Nuclear Information System (INIS)

Cesareo, Roberto; Brunetti, Antonio; Assis, Joaquim T. de

2013-01-01

Objects composed of two or more layers are relatively common among industrial and electronic materials, works of art and common tools. For example plated objects (with zinc, nickel, silver, gold) are composed of two or three layers, a painting is generally composed of several layers, a decorated vase is composed of two or three layers, just as a stone, marble or bronze covered with a protective layer. In this paper a general method and some results are described to reconstruct structure and to determine thicknesses of multilayered material, when energy dispersive X-ray fluorescence is employed to analyze the material: the X-ray ratios of Kα/Kβ and Lα/Lβ for elements present in the multilayered samples are employed. (author)

Connection between effective-range expansion and nuclear vertex constant or asymptotic normalization coefficient

International Nuclear Information System (INIS)

Yarmukhamedov, R.; Baye, D.

2011-01-01

Explicit relations between the effective-range expansion and the nuclear vertex constant or asymptotic normalization coefficient (ANC) for the virtual decay B→A+a are derived for an arbitrary orbital momentum together with the corresponding location condition for the (A+a) bound-state energy. They are valid both for the charged case and for the neutral case. Combining these relations with the standard effective-range function up to order six makes it possible to reduce to two the number of free effective-range parameters if an ANC value is known from experiment. Values for the scattering length, effective range, and form parameter are determined in this way for the 16 O+p, α+t, and α+ 3 He collisions in partial waves where a bound state exists by using available ANCs deduced from experiments. The resulting effective-range expansions for these collisions are valid up to energies larger than 5 MeV.

Soil Compressibility Models for a Wide Stress Range

KAUST Repository

Chong, Song-Hun; Santamarina, Carlos

2016-01-01

Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low

Influence of accommodative lag upon the far-gradient measurement of accommodative convergence to accommodation ratio in strabismic patients.

Science.gov (United States)

Miyata, Manabu; Hasebe, Satoshi; Ohtsuki, Hiroshi

2006-01-01

To determine the influence of the lag of accommodation (LOA) on the accommodative convergence to accommodation (AC/A) ratio measured by the far-gradient method in strabismic patients. The AC/A ratio was measured with a distance target viewed with and without -3.00 diopter (D) addition lenses in 63 patients with different types of strabismus (age range, 7-34 years; range of strabismic angle, -60 to +40 prism diopters; refractive error range, -7.33 to +6.63 D). The LOA for the same lens was measured with an open-view-type autorefractometer. The stimulus AC/A ratio and the AC/A ratio adjusted by the individually measured LOA (adjusted AC/A ratio) were compared. The mean +/- SD of the LOA to the -3.00 D lenses was 1.06 +/- 0.43 D. The mean adjusted AC/A ratio was 41% greater than the stimulus AC/A ratio. The LOA differed widely among patients (0.13 to 2.14 D), and a large LOA tended to appear in myopic or young patients. The AC/A ratio obtained using the conventional far-gradient method is significantly biased by the LOA, and thus does not always represent the actual relationship between accommodation and vergence control systems. Copyright Japanese Ophthalmological Society 2006.

Kβ/Kα X-ray intensity ratios for some elements in the atomic number range 28≤Z≤39 at 16.896 keV

Directory of Open Access Journals (Sweden)

R. Yılmaz

2017-07-01

Full Text Available The K shell intensity ratios (Kβ/Kα have been experimentally determined for some elements in the atomic number range 28 ≤ Z ≤ 39 by using secondary excitation method. K X-rays emitted by samples have been counted by a Si (Li detector with 160 eV resolutions at 5.9 keV. The measured values were compared with the theoretical and experimental values. In general, the values obtained are in good agreement with the calculated values.

Correlation of normal-range FMR1 repeat length or genotypes and reproductive parameters.

Science.gov (United States)

Maslow, Bat-Sheva L; Davis, Stephanie; Engmann, Lawrence; Nulsen, John C; Benadiva, Claudio A

2016-09-01

This study aims to ascertain whether the length of normal-ranged CGG repeats on the FMR1 gene correlates with abnormal reproductive parameters. We performed a retrospective, cross-sectional study of all FMR1 carrier screening performed as part of routine care at a large university-based fertility center from January 2011 to March 2014. Correlations were performed between normal-range FMR1 length and baseline serum anti-Müllerian hormone (AMH), cycle day 3 follicle stimulating hormone (FSH), ovarian volumes (OV), antral follicle counts (AFC), and incidence of diminished ovarian reserve (DOR), while controlling for the effect of age. Six hundred three FMR1 screening results were collected. One subject was found to be a pre-mutation carrier and was excluded from the study. Baseline serum AMH, cycle day 3 FSH, OV, and AFC data were collected for the 602 subjects with normal-ranged CGG repeats. No significant difference in median age was noted amongst any of the FMR1 repeat genotypes. No significant correlation or association was found between any allele length or genotype, with any of the reproductive parameters or with incidence of DOR at any age (p > 0.05). However, subjects who were less than 35 years old with low/low genotype were significantly more likely to have below average AMH levels compared to those with normal/normal genotype (RR 3.82; 95 % CI 1.38-10.56). This large study did not demonstrate any substantial association between normal-range FMR1 repeat lengths and reproductive parameters.

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

VVER-1000 dominance ratio

International Nuclear Information System (INIS)

Gorodkov, S.

2009-01-01

Dominance ratio, or more precisely, its closeness to unity, is important characteristic of large reactor. It allows evaluate beforehand the number of source iterations required in deterministic calculations of power spatial distribution. Or the minimal number of histories to be modeled for achievement of statistical error level desired in large core Monte Carlo calculations. In this work relatively simple approach for dominance ratio evaluation is proposed. It essentially uses core symmetry. Dependence of dominance ratio on neutron flux spatial distribution is demonstrated. (author)

WWER-1000 dominance ratio

International Nuclear Information System (INIS)

Gorodkov, S.S.

2009-01-01

Dominance ratio, or more precisely, its closeness to unity, is important characteristic of large reactor. It allows evaluate beforehand the number of source iterations required in deterministic calculations of power spatial distribution. Or the minimal number of histories to be modeled for achievement of statistical error level desired in large core Monte Carlo calculations. In this work relatively simple approach for dominance ratio evaluation is proposed. It essentially uses core symmetry. Dependence of dominance ratio on neutron flux spatial distribution is demonstrated. (Authors)

Oral fluid/plasma cannabinoid ratios following controlled oral THC and smoked cannabis administration.

Science.gov (United States)

Lee, Dayong; Vandrey, Ryan; Milman, Garry; Bergamaschi, Mateus; Mendu, Damodara R; Murray, Jeannie A; Barnes, Allan J; Huestis, Marilyn A

2013-09-01

Oral fluid (OF) is a valuable biological alternative for clinical and forensic drug testing. Evaluating OF to plasma (OF/P) cannabinoid ratios provides important pharmacokinetic data on the disposition of drug and factors influencing partition between matrices. Eleven chronic cannabis smokers resided on a closed research unit for 51 days. There were four 5-day sessions of 0, 30, 60, and 120 mg oral ∆(9)-tetrahydrocannabinol (THC)/day followed by a five-puff smoked cannabis challenge on Day 5. Each session was separated by 9 days ad libitum cannabis smoking. OF and plasma specimens were analyzed for THC and metabolites. During ad libitum smoking, OF/P THC ratios were high (median, 6.1; range, 0.2-348.5) within 1 h after last smoking, decreasing to 0.1-20.7 (median, 2.1) by 13.0-17.1 h. OF/P THC ratios also decreased during 5-days oral THC dosing, and after the smoked cannabis challenge, median OF/P THC ratios decreased from 1.4 to 5.5 (0.04-245.6) at 0.25 h to 0.12 to 0.17 (0.04-5.1) at 10.5 h post-smoking. In other studies, longer exposure to more potent cannabis smoke and oromucosal cannabis spray was associated with increased OF/P THC peak ratios. Median OF/P 11-nor-9-carboxy-THC (THCCOOH) ratios were 0.3-2.5 (range, 0.1-14.7) ng/μg, much more consistent in various dosing conditions over time. OF/P THC, but not THCCOOH, ratios were significantly influenced by oral cavity contamination after smoking or oromucosal spray of cannabinoid products, followed by time-dependent decreases. Establishing relationships between OF and plasma cannabinoid concentrations is essential for making inferences of impairment or other clinical outcomes from OF concentrations.

Video-rate or high-precision: a flexible range imaging camera

Science.gov (United States)

Dorrington, Adrian A.; Cree, Michael J.; Carnegie, Dale A.; Payne, Andrew D.; Conroy, Richard M.; Godbaz, John P.; Jongenelen, Adrian P. P.

2008-02-01

A range imaging camera produces an output similar to a digital photograph, but every pixel in the image contains distance information as well as intensity. This is useful for measuring the shape, size and location of objects in a scene, hence is well suited to certain machine vision applications. Previously we demonstrated a heterodyne range imaging system operating in a relatively high resolution (512-by-512) pixels and high precision (0.4 mm best case) configuration, but with a slow measurement rate (one every 10 s). Although this high precision range imaging is useful for some applications, the low acquisition speed is limiting in many situations. The system's frame rate and length of acquisition is fully configurable in software, which means the measurement rate can be increased by compromising precision and image resolution. In this paper we demonstrate the flexibility of our range imaging system by showing examples of high precision ranging at slow acquisition speeds and video-rate ranging with reduced ranging precision and image resolution. We also show that the heterodyne approach and the use of more than four samples per beat cycle provides better linearity than the traditional homodyne quadrature detection approach. Finally, we comment on practical issues of frame rate and beat signal frequency selection.

Metabolic control by sirtuins and other enzymes that sense NAD+, NADH, or their ratio.

Science.gov (United States)

Anderson, Kristin A; Madsen, Andreas S; Olsen, Christian A; Hirschey, Matthew D

2017-12-01

NAD + is a dinucleotide cofactor with the potential to accept electrons in a variety of cellular reduction-oxidation (redox) reactions. In its reduced form, NADH is a ubiquitous cellular electron donor. NAD + , NADH, and the NAD + /NADH ratio have long been known to control the activity of several oxidoreductase enzymes. More recently, enzymes outside those participating directly in redox control have been identified that sense these dinucleotides, including the sirtuin family of NAD + -dependent protein deacylases. In this review, we highlight examples of non-redox enzymes that are controlled by NAD + , NADH, or NAD + /NADH. In particular, we focus on the sirtuin family and assess the current evidence that the sirtuin enzymes sense these dinucleotides and discuss the biological conditions under which this might occur; we conclude that sirtuins sense NAD + , but neither NADH nor the ratio. Finally, we identify future studies that might be informative to further interrogate physiological and pathophysiological changes in NAD + and NADH, as well as enzymes like sirtuins that sense and respond to redox changes in the cell. Copyright © 2017 Elsevier B.V. All rights reserved.

The varying distribution of intra- and inter-vertebral height ratios determines the prevalence of vertebral fractures.

Science.gov (United States)

Zebaze, Roger Martin Djoumessi; Djoumessi, Roger Martin Zebaze; Maalouf, Ghassan; Wehbe, Joseph; Nehme, Alexandre; Maalouf, Naim; Seeman, Ego

2004-08-01

Credible inferences regarding the burden of vertebral fractures (VFs) cannot be made without a globally accepted quantitative definition of 'fracture'. Currently, differences in anterior, middle, or posterior vertebral heights (VHs) within a vertebra, or between adjacent vertebrae, are used to define 'fracture'. However, VH differences are essential for the construction of thoracolumbar curves, evolutionary adaptations that provide stability in bipedal stance and gait. As there is no reference standard to distinguish anatomical variation from fracture, approaches to defining a VF use a reference range of VH ratios derived in premenopausal women or derived by trimming, a method that iteratively removes the tails of a distribution of VH ratios to produce a normal distribution. From this, reference ranges of VH ratio means and standard deviations (SDs) are obtained and a nominal deviation of 15% or more, or 3 SD or more is regarded as a 'fracture'. We measured VHs by quantitative vertebral morphometry (QVM) and bone mineral density (BMD) by dual energy X-ray absorptiometry in 697 Lebanese women (age 20-89 years) to compare the prevalence of VF ascertained by published methods and a new method that uses the premenopausal range (without trimming) and requires two VH abnormalities. VF prevalence using published methods reached 60% to 70% in pre- and post-menopausal women, and in women with normal or high BMD because VH ratios were not normally distributed and cut-offs used to define VF fracture fell within the observed distribution of the data. The new method resulted in a VF prevalence of 3.3% in younger and 14% in older women, 7% (high), 10% (middle), and 20% (low) BMD tertiles consistent with the notion that the method detected VF due to bone fragility. We suggest that using a fixed trimming method to define reference range and cut-offs or applying fixed cut-offs to identify VFs in populations, where these ratios are not normally distributed, may result in the capture

Neutron activation analysis of calcium/phosphorus ratio in rib bone of healthy humans

International Nuclear Information System (INIS)

Tzaphlidou, Margaret; Zaichick, Vladimir

2002-01-01

The Ca/P ratio was estimated in intact rib bone samples from healthy humans, 37 women and 45 men, aged from 15 to 55 years using instrumental neutron activation analysis. No statistically significant differences (p>0.05) age- or sex-related differences in the Ca/P ratio were observed. The mean value (M±SD) for the investigated parameter for the whole group studied, 2.33±0.34, was within a very wide range of published data and close to the median value

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

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.

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.

FeII/MgII Emission Line Ratio in High Redshift Quasars

DEFF Research Database (Denmark)

Dietrich, M.; Hamann, F.; Appenzeller, I.

2003-01-01

the evolution of the FeII/MgII ratio over a wider range in cosmic time, we measured this ratio for composite quasar spectra which cover a redshift range of 0 4 quasars must have started already at an epoch corresponding to z_f = 6 to 9, when the age of the universe was ~0.5 Gyr (H_o = 72 km/s/Mpc, Omega_M = 0...

Comparison of hematocrit/hemoglobin ratios in subjects with alpha-thalassemia, with subjects having chronic kidney disease and normal subjects.

Science.gov (United States)

Insiripong, Somchai; Supattarobol, Tanarat; Jetsrisuparb, Arunee

2013-07-04

The ratio of hematocrit (Hct) to hemoglobin (Hb) in the people with normal red blood cell (RBC) morphology is generally three to one. We studied Hct/Hb ratios among patients with alpha-thalassemias (Hb H, H-CS, AEBart, AEBart-CS, EFBart and EFBart-CS diseases) diagnosed by high performance liquid chromatography, and compared them with normal subjects and with patients having anemia due to chronic kidney disease (CKD). The Hct and Hb levels were derived by automated analyzer. The means +/- SD of the Hct/Hb ratios were 3.5 +/- 0.2 (range 3.3 - 4.1), 3.0 +/- 0.1 (range 2.9 - 3.2) and 3.0 +/- 0.1 (range 2.8 - 3.2) in the alpha-thalassemia, normal and CKD groups, respectively. The mean Hct/Hb ratio in subjects with alpha-thalassemia was higher than the mean in normal subjects and in those with CKD. The Hct/Hb ratios for each genotype of the alpha-thalassemia were not different from each other. The underlying mechanisms for the higher Hct/Hb ratio among those with alpha-thalassemia are theorized to be less density and/or more hydration of a-thalassemia RBCs, more entrapment of plasma in the spun RBC, the high percent of nucleated RBC and WBC interference. A ratio of 3.5 +/- 0.2 may be helpful in cases of moderate anemia when typing only shows Hb A and E, to consider investigation for alpha-thalassemia, or in cases of alpha-thalassemia with acute blood loss, if the Hct is less than 35%, in the decision to transfuse.

Wide dynamic range beam profile monitor

International Nuclear Information System (INIS)

Lee, D.M.; Brown, D.; Hardekopf, R.; Bilskie, J.R.; van Dyck, O.B.V.

1985-01-01

An economical harp multiplexer system has been developed to achieve a wide dynamic range. The harp system incorporates a pneumatically actuated harp detector with ceramic boards and carbon wires; a high-sensitivity multiplexer packaged in a double-wide NIM module; and flat, shielded ribbon cable consisting of individual twisted pairs. The system multiplexes 30 wires in each of the x and y planes simultaneously and operates with or without computer control. The system has operated in beams of 100 nA to 1 mA, 1- to 120-Hz repetition rate, with a signal-to-noise ratio of greater than 10/1

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

Science.gov (United States)

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

1995-01-01

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

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.

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

Science.gov (United States)

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

2017-12-15

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

Evolutionary differences in Δ13C detected between spore and seed bearing plants following exposure to a range of atmospheric O2:CO2 ratios; implications for paleoatmosphere reconstruction

Science.gov (United States)

Porter, Amanda S.; Yiotis, Charilaos; Montañez, Isabel P.; McElwain, Jennifer C.

2017-09-01

The stable carbon isotopes of fossil plants are a reflection of the atmosphere and environment in which they grew. Fossil plant remains have thus stored information about the isotopic composition and concentration of atmospheric carbon dioxide (pCO2) and possibly pO2 through time. Studies to date, utilizing extant plants, have linked changes in plant stable carbon isotopes (δ13Cp) or carbon isotope discrimination (Δ13C) to changes in pCO2 and/or pO2. These studies have relied heavily on angiosperm representatives, a phylogenetic group only present in the fossil record post-Early Cretaceous (∼140 million years ago (mya)), whereas gymnosperms, monilophytes and lycophytes dominated terrestrial ecosystems prior to this time. The aim of this study was to expand our understanding of carbon isotope discrimination in all vascular plant groups of C3 plants including lycophytes, monilophytes, gymnosperms and angiosperms, under elevated CO2 and sub-ambient O2 to explore their utility as paleo-atmospheric proxies. To achieve this goal, plants were grown in controlled environment chambers under a range of O2:CO2 ratio treatments. Results reveal a strong phylogenetic dependency on Δ13C, where spore-bearing (lycophytes and monilophytes) have significantly higher 13C discrimination than seed plants (gymnosperms and angiosperms) by ∼5‰. We attribute this strong phylogenetic signal to differences in Ci/Ca likely mediated by fundamental differences in how spore and seed bearing plants control stomatal aperture. Decreasing O2:CO2 ratio in general resulted in increased carbon isotope discrimination in all plant groups. Notably, while all plant groups respond unidirectionally to elevated atmospheric CO2 (1900 ppm and ambient O2), they do not respond equally to sub-ambient O2 (16%). We conclude that (1) Δ13C has a strong phylogenetic or 'reproductive grade' bias, whereby Δ13C of spore reproducing plants is significantly different to seed reproducing taxa. (2) Δ13C increases

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...

Overwinter changes in urea nitrogen:creatinine and cortisol:creatinine ratios in urine from Banks Island Peary caribou

Directory of Open Access Journals (Sweden)

Nicholas C. Larter

2000-04-01

Full Text Available Over 200 snow urine samples were collected from Banks Island Peary caribou between March 1993 and May 1998. Most (n = 146 samples were collected during 3 time periods in 5 successive years: early winter (3 November-3 December, mid-winter (9 February-1 March, and late-winter (23 April-2 May. We determined the ratios of urea nitrogen:creatinine (U:C and cortisol:creatinine (C:C for each sample. U:C ratios had significant year, time, and year x time interaction effects. Mid-winter ratios were higher than early or late-winter ratios. U:C ratios ranged from 0.53 to 19.05 mg/mg, and were lowest in 1997-98. Five calf caribou sacrificed in February 1994 had significantly (P<0.02 higher U:C ratios than other caribou in mid-winter. Three adult male and 2 calf caribou sacrificed in November 1993 had U:C ratios similar to other caribou in early winter. Sacrificed caribou were in similar condition to animals that have been harvested for subsistent use in other years, not overly fat nor in an advanced state of starvation. U:C ratios for Peary caribou range from 10 to ca. 100-fold higher than those reported for barren-ground caribou; ratios > 60-fold higher than those indicative of prolonged undernutrition in barren-ground caribou were common. This difference is likely because the winter diet of Peary caribou has a higher crude protein content than that of barren-ground caribou. C:C ratios had significant year and year x time interaction effects, and were highest in 1996-97 and 1997-98. C:C ratios of sacrificed caribou were similar to those of other animals during early and mid-winter. C:C ratios for Peary caribou ranged from 0.0120 ug/mg to 0.2678 ug/mg; ratios indicative of morbidity in mule deer were common. C:C and U:C ratios from the same individuals were not correlated (R = -0.073. Monitoring U:C ratios of Banks Island Peary caribou may provide useful management information.

Effect of elimination of nitrogen and/or hypoxia or restricted visual environment on color vision and range of accommodation

Science.gov (United States)

Wolbarsht, M. L.; White, C. W.; Anderson, W. B., Jr.

1973-01-01

The effects upon range of accommodation and color vision of reduced atmospheric pressure, at partial and complete elimination of nitrogen, of hypoxia, and of exposure for varying periods of time to restricted visual environment, have been studied alone or in various combinations. Measurements were made on the electroretinogram, the electrooculogram, and the diameter of the retinal vessels as an indicator of blood flow to the retina at the time of total elimination of nitrogen. An objective method was used to test range of accommodation. In the color vision test the flicker colors of a Benham's top were matched with a colorimeter.

Glucose in prediabetic and diabetic range and outcome after stroke.

Science.gov (United States)

Osei, E; Fonville, S; Zandbergen, A A M; Koudstaal, P J; Dippel, D W J; den Hertog, H M

2017-02-01

Newly diagnosed disturbed glucose metabolism is highly prevalent in patients with stroke. Limited data are available on their prognostic value on outcome after stroke. We aimed to assess the association of glucose in the prediabetic and diabetic range with unfavourable short-term outcome after stroke. We included 839 consecutive patients with ischemic stroke and 168 patients with intracerebral haemorrhage. In all nondiabetic patients, fasting glucose levels were determined on day 2-4. Prediabetic range was defined as fasting glucose of 5.6-6.9 mmol/L, diabetic range as ≥7.0 mmol/L, pre-existent diabetes as the use of anti-diabetic medication prior to admission. Outcome measures were poor functional outcome or death defined as modified Rankin Scale (mRS) score >2 and discharge not to home. The association of prediabetic range, diabetic range and pre-existent diabetes (versus normal glucose) with unfavourable outcome was expressed as odds ratios, estimated with multiple logistic regression, with adjustment for prognostic factors. Compared with normal glucose, prediabetic range (aOR 1.8; 95%CI 1.1-2.8), diabetic range (aOR 2.5; 95%CI 1.3-4.9) and pre-existent diabetes (aOR 2.6; 95%CI 1.6-4.0) were associated with poor functional outcome or death. Patients in the prediabetic range (aOR 0.6; 95%CI 0.4-0.9), diabetic range (aOR 0.4; 95%CI 0.2-0.9) and pre-existent diabetes (aOR 0.6; 95%CI 0.4-0.9) were more likely not to be discharged to home. Patients with glucose in the prediabetic and diabetic range have an increased risk of unfavourable short-term outcome after stroke. These findings illustrate the potential impact of early detection and treatment of these patients. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A test procedure for determining the influence of stress ratio on fatigue crack growth

Science.gov (United States)

Fitzgerald, J. H.; Wei, R. P.

1974-01-01

A test procedure is outlined by which the rate of fatigue crack growth over a range of stress ratios and stress intensities can be determined expeditiously using a small number of specimens. This procedure was developed to avoid or circumvent the effects of load interactions on fatigue crack growth, and was used to develop data on a mill annealed Ti-6Al-4V alloy plate. Experimental data suggest that the rates of fatigue crack growth among the various stress ratios may be correlated in terms of an effective stress intensity range at given values of K max. This procedure is not to be used, however, for determining the corrosion fatigue crack growth characteristics of alloys when nonsteady-state effects are significant.

E2,M1 multipole mixing ratios in even--even nuclei, A greater than or equal to 152

International Nuclear Information System (INIS)

Krane, K.S.

1975-01-01

A survey is presented of E2,M1 mixing ratios of gamma-ray transitions in even-even nuclei with mass numbers A greater than or equal to 152. Angular distribution and correlation data from the literature are analyzed in terms of a consistent choice of the phase relationship between the E2 and M1 matrix elements. The cutoff date for the literature was June 1975. Based on an average of the experimental results from the literature, a recommended value of the E2,M1 mixing ratio for each transition is included

Validation of a noninvasive diagnostic tool to verify neuter status in dogs: The urinary FSH to creatinine ratio.

Science.gov (United States)

Albers-Wolthers, C H J; de Gier, J; Oei, C H Y; Schaefers-Okkens, A C; Kooistra, H S

2016-09-15

Determining the presence of functional gonadal tissue in dogs can be challenging, especially in bitches during anestrus or not known to have been ovariectomized, or in male dogs with nonscrotal testes. Furthermore, in male dogs treated with deslorelin, a slow-release GnRH agonist implant for reversible chemical castration, the verification of complete downregulation of the hypothalamic-pituitary-gonadal (HPG) axis can be difficult, especially if pretreatment parameters such as the size of the testes or prostate gland are not available. The aims of this study were to validate an immunoradiometric assay for measurement of FSH in canine urine, to determine if the urinary FSH to creatinine ratio can be used to verify the neuter status in bitches and male dogs, as an alternative to the plasma FSH concentration, and to determine if downregulation of the HPG axis is achieved in male dogs during deslorelin treatment. Recovery of added canine FSH and serial dilutions of urine reported that the immunoradiometric assay measures urinary FSH concentration accurately and with high precision. Plasma FSH concentrations (the mean of two samples, taken 40 minutes apart) and the urinary FSH to creatinine ratio were determined before gonadectomy and 140 days (median, range 121-225 days) and 206 days (median, range 158-294 days) after gonadectomy of 13 bitches and five male dogs, respectively, and in 13 male dogs before and 132 days (median, range 117-174 days) after administration of a deslorelin implant. In both bitches and male dogs, the plasma FSH concentration and the urinary FSH to creatinine ratio were significantly higher after gonadectomy, with no overlapping of their ranges. Receiver operating characteristic analysis of the urinary FSH to creatinine ratio revealed a cut-off value of 2.9 in bitches and 6.5 in males to verify the presence or absence of functional gonadal tissue. In male dogs treated with deslorelin, the plasma FSH concentrations and urinary FSH to

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.

Evaluation of diffuse diseases of the upper abdominal organs by MRI. Determination of a normal range in signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images and evaluation of diffuse diseases of an organ by using it

International Nuclear Information System (INIS)

Mitsuhashi, Hiroshi

1995-01-01

Diffuse diseases of the upper abdominal organs, including the liver, spleen, pancreas, and vertebral marrow, were evaluated by using signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images. Conventional T1- and T2-weighted images were obtained in 1.5 T MR system in 203 persons, including 122 controls and 81 patients with a diffuse disease in the upper abdominal organ. In controls, though there was neither sexual nor age difference in signal intensity ratios of the liver and pancreas, those of the spleen and vertebral marrow showed sexual and age difference, respectively. A normal range of signal intensity ratio of each organ in each image was determined in each decade of each sex by using controls. The signal intensity ratio of the liver was significantly low in T1- and T2-weighted images in patients with abundant iron deposit and within normal limits in patients with liver cirrhosis or scant iron deposit. The signal intensity ratio of the liver was significantly high only in a T2-weighted image in patients with fatty deposit in the liver, which was suspected to be due to inflammatory change in the liver with fatty deposit. The signal intensity ratios of the spleen, pancreas, and vertebral marrow were significantly low only in a T2-weighted image in patients with iron metabolic disturbance. The signal intensity ratio of the pancreas was significantly high in 40% of patients with acute and/or chronic pancreatitis, which was more sensitive in detection of pancreatitis than data in other studies. it can be concluded that the signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images is useful for detection of diffuse diseases of the upper abdominal organs by using the normal range in each decade of each sex. (S.Y.)

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

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

Energy Technology Data Exchange (ETDEWEB)

Doolan, P. J., E-mail: paul.doolan.09@ucl.ac.uk; Royle, G.; Gibson, A. [Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT (United Kingdom); Lu, H.-M. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Prieels, D.; Bentefour, E. H. [Ion Beam Applications (IBA), 3 Chemin du Cyclotron, Louvain la Neuve B-1348 (Belgium)

2015-04-15

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

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.

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 ...

The e/h ratio of the ATLAS hadronic tile calorimeter

International Nuclear Information System (INIS)

Budagov, Yu.A.; Vinogradov, V.B.; Kul'chitskij, Yu.A.; Kuz'min, M.V.

2002-01-01

We have determined the e/h ratios of the Module-0 of the ATLAS iron-scintillator barrel hadron tile calorimeter for five values of pseudorapidity η in the range of -0.55 ≤ η ≤ -0.15 for the beam energy range from 10 to 300 GeV on the basis of the July 1999 test beam data. These e/h ratios demonstrate independence from |η| value. The mean value is e/h = 1.362 + 0.006. The results are compared with the existing experimental data and with some Monte Carlo calculations

Raman ratios on the repair of grafted surgical bone defects irradiated or not with laser (λ780 nm) or LED (λ850 nm).

Science.gov (United States)

Pinheiro, Antonio Luiz B; Soares, Luiz Guilherme P; Marques, Aparecida Maria C; Aciole, Jouber Mateus S; de Souza, Renato Aparecido; Silveira, Landulfo

2014-09-05

This work aimed to assess biochemical changes associated to mineralization and remodeling of bone defects filled with Hydroxyapatite+Beta-Beta-tricalcium phosphate irradiated or not with 2 light sources. Ratios of intensities, band position and bandwidth of selected Raman peaks of collagen and apatites were used. Sixty male Wistar rats were divided into 6 groups subdivided into 2 subgroups (15th and 30th days). A standard surgical defect was created on one femur of each animal. In 3 groups the defects were filled with blood clot (Clot, Clot+Laser and Clot+LED groups) and in the remaining 3 groups the defects were filled with biomaterial (Biomaterial, Biomaterial+Laser and Biomaterial+LED groups). When indicated, the defects were irradiated with either Laser (λ780 nm, 70 mW, Φ∼0.4 cm(2)) or LED (λ850±10 nm, 150 mW, Φ∼0.5 cm(2)), 20 J/cm(2) each session, at 48 h intervals/2 weeks (140 J/cm(2) treatment). Following sacrifice, bone fragments were analyzed by Raman spectroscopy. Statistical analysis (ANOVA General Linear Model, pRaman ratios of selected protein matrix and phosphate and carbonate HA indicated that the use of biphasic synthetic micro-granular HA+Beta-TCP graft improved the repair of bone defects, associated or not with Laser or LED light, because of the increasing deposition of HA. Copyright © 2014 Elsevier B.V. All rights reserved.

The Measurement of Fuel-air Ratio by Analysis of the Oxidized Exhaust Gas

Science.gov (United States)

Memm, J. Lawrence, Jr.

1943-01-01

An investigation was made to determine a method of measuring fuel-air ratio that could be used for test purposes in flight and for checking conventional equipment in the laboratory. Two single-cylinder test engines equipped with typical commercial engine cylinders were used. The fuel-air ratio of the mixture delivered to the engines was determined by direct measurement of the quantity of air and of fuel supplied and also by analysis of the oxidized exhaust gas and of the normal exhaust gas. Five fuels were used: gasoline that complied with Army-Navy Fuel Specification, No. AN-VV-F-781 and four mixtures of this gasoline with toluene, benzene, and xylene. The method of determining the fuel-air ratio described in this report involves the measurement of the carbon-dioxide content of the oxidized exhaust gas and the use of graphs or the presented equation. This method is considered useful in aircraft, in the field, or in the laboratory for a range of fuel-air ratios from 0.047 to 0.124

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 ...

High aspect ratio channels in glass and porous silicon

Energy Technology Data Exchange (ETDEWEB)

Liang, H.D. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Nanoscience and Nanotechnology Initiative (NNI), National University of Singapore, Singapore 117411 (Singapore); Dang, Z.Y. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Wu, J.F. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583 (Singapore); Kan, J.A. van; Qureshi, S. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Ynsa, M.D.; Torres-Costa, V. [Department of Applied Physics, Universidad Autónoma de Madrid, Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Centro de Micro-Análisis de Materiales (CMAM), Universidad Autónoma de Madrid, Campus de Cantoblanco Edif. 22, Faraday 3, E-28049 Madrid (Spain); Maira, A. [Department of Applied Physics, Universidad Autónoma de Madrid, Madrid, Campus de Cantoblanco, 28049 Madrid (Spain); Venkatesan, T.V. [Nanoscience and Nanotechnology Initiative (NNI), National University of Singapore, Singapore 117411 (Singapore); Breese, M.B.H., E-mail: phymbhb@nus.edu.sg [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

2017-03-01

We have developed a micromachining process to produce high-aspect-ratio channels and holes in glass and porous silicon. Our process utilizes MeV proton beam irradiation of silicon using direct writing with a focused beam, followed by electrochemical etching. To increase throughput we have also developed another process for large area ion irradiation based on a radiation-resistant gold surface mask, allowing many square inches to be patterned. We present a study of the achievable channel width, depth and period and sidewall verticality for a range of channels which can be over 100 μm deep or 100 nm wide with aspect ratios up to 80. This process overcomes the difficulty of machining glass on a micro- and nanometer scale which has limited many areas of applications in different fields such as microelectronics and microfluidics.

Bone/soft-tissue enrichment ratio in skeletal scintiscanning

International Nuclear Information System (INIS)

Reuschel, W.

1982-01-01

The thesis aimed at establishing normal values for the enrichment intensity of sup(99m)Tc-MDP above the sacrum (S) as reference point for spongy bones in relation to soft-tissue (ST) enrichment (S/St ratio). A normal range for S/ST was determined for five age groups which was given separately for males and females. In addition, the question was examined what causes there could be for S/ST exceeding, the norm or an increased F/ST ratio (F=femur centre) between bone and soft tissue. The question was studied whether or not beniguity or malignancy of a base disease has an important influence on F/ST values. Dependence of F/ST values from primary tumour localization and the tendency of metastatic spread in bones were investigated in malignoma patients. In addition, an assessment was made of what correlation existed, between the laboratory parameters measured, particularly alkaline phosphatase, and the F/ST values. The questions were examined what correlation existed between the F/ST values established and scintiscan findings; whether or not solitary radionuclide enrichments or multiple foci were found in the scintiscan; and what influence the number of foci had on the F/ST values. In tumour patients, the question examined what correlation existed between a tumour-specific treatment and the F/ST values. (orig./MG) [de

Controls over foliar N:P ratios in tropical rain forests.

Science.gov (United States)

Townsend, Alan R; Cleveland, Cory C; Asner, Gregory P; Bustamante, Mercedes M C

2007-01-01

Correlations between foliar nutrient concentrations and soil nutrient availability have been found in multiple ecosystems. These relationships have led to the use of foliar nutrients as an index of nutrient status and to the prediction of broadscale patterns in ecosystem processes. More recently, a growing interest in ecological stoichiometry has fueled multiple analyses of foliar nitrogen:phosphorus (N:P) ratios within and across ecosystems. These studies have observed that N:P values are generally elevated in tropical forests when compared to higher latitude ecosystems, adding weight to a common belief that tropical forests are generally N rich and P poor. However, while these broad generalizations may have merit, their simplicity masks the enormous environmental heterogeneity that exists within the tropics; such variation includes large ranges in soil fertility and climate, as well as the highest plant species diversity of any biome. Here we present original data on foliar N and P concentrations from 150 mature canopy tree species in Costa Rica and Brazil, and combine those data with a comprehensive new literature synthesis to explore the major sources of variation in foliar N:P values within the tropics. We found no relationship between N:P ratios and either latitude or mean annual precipitation within the tropics alone. There is, however, evidence of seasonal controls; in our Costa Rica sites, foliar N:P values differed by 25% between wet and dry seasons. The N:P ratios do vary with soil P availability and/or soil order, but there is substantial overlap across coarse divisions in soil type, and perhaps the most striking feature of the data set is variation at the species level. Taken as a whole, our results imply that the dominant influence on foliar N:P ratios in the tropics is species variability and that, unlike marine systems and perhaps many other terrestrial biomes, the N:P stoichiometry of tropical forests is not well constrained. Thus any use of N

A prediction model for wind speed ratios at pedestrian level with simplified urban canopies

Science.gov (United States)

Ikegaya, N.; Ikeda, Y.; Hagishima, A.; Razak, A. A.; Tanimoto, J.

2017-02-01

The purpose of this study is to review and improve prediction models for wind speed ratios at pedestrian level with simplified urban canopies. We adopted an extensive database of velocity fields under various conditions for arrays consisting of cubes, slender or flattened rectangles, and rectangles with varying roughness heights. Conclusions are summarized as follows: first, a new geometric parameter is introduced as a function of the plan area index and the aspect ratio so as to express the increase in virtual density that causes wind speed reduction. Second, the estimated wind speed ratios in the range 0.05 coefficients between the wind speeds averaged over the entire region, and the front or side region values are larger than 0.8. In contrast, in areas where the influence of roughness elements is significant, such as behind a building, the wind speeds are weakly correlated.

Odds Ratio or Prevalence Ratio? An Overview of Reported Statistical Methods and Appropriateness of Interpretations in Cross-sectional Studies with Dichotomous Outcomes in Veterinary Medicine

Directory of Open Access Journals (Sweden)

Brayan Alexander Fonseca Martinez

2017-11-01

Full Text Available One of the most commonly observational study designs employed in veterinary is the cross-sectional study with binary outcomes. To measure an association with exposure, the use of prevalence ratios (PR or odds ratios (OR are possible. In human epidemiology, much has been discussed about the use of the OR exclusively for case–control studies and some authors reported that there is no good justification for fitting logistic regression when the prevalence of the disease is high, in which OR overestimate the PR. Nonetheless, interpretation of OR is difficult since confusing between risk and odds can lead to incorrect quantitative interpretation of data such as “the risk is X times greater,” commonly reported in studies that use OR. The aims of this study were (1 to review articles with cross-sectional designs to assess the statistical method used and the appropriateness of the interpretation of the estimated measure of association and (2 to illustrate the use of alternative statistical methods that estimate PR directly. An overview of statistical methods and its interpretation using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA guidelines was conducted and included a diverse set of peer-reviewed journals among the veterinary science field using PubMed as the search engine. From each article, the statistical method used and the appropriateness of the interpretation of the estimated measure of association were registered. Additionally, four alternative models for logistic regression that estimate directly PR were tested using our own dataset from a cross-sectional study on bovine viral diarrhea virus. The initial search strategy found 62 articles, in which 6 articles were excluded and therefore 56 studies were used for the overall analysis. The review showed that independent of the level of prevalence reported, 96% of articles employed logistic regression, thus estimating the OR. Results of the multivariate models

Effects of particle exhaust on neutral compression ratios in DIII-D

International Nuclear Information System (INIS)

Colchin, R.J.; Maingi, R.; Wade, M.R.; Allen, S.L.; Greenfield, C.M.

1998-08-01

In this paper, neutral particles in DIII-D are studied via their compression in the plenum and via particle exhaust. The compression of gas in the plena is examined in terms of the magnetic field configuration and wall conditions. DIII-D compression ratios are observed in the range from 1 to ≥ 1,000. Particle control ultimately depends on the exhaust of neutrals via plenum or wall pumping. Wall pumping or outgassing is calculated by means of a detailed particle balance throughout individual discharges, and its effect on particle control is discussed. It is demonstrated that particle control through wall conditioning leads to lower normalized densities. A two-region model shows that the gas compression ratio (C div = divertor plenum neutral pressure/torus neutral pressure) can be interpreted in relation to gas flows in the torus and divertor including the pumping speed of the plenum cryopumps, plasma pumping, and the pumping or outgassing of the walls

Hydrogeochemical and stream sediment detailed geochemical survey for Thomas Range-Wasatch, Utah. Farmington Project area

International Nuclear Information System (INIS)

Butz, T.R.; Bard, C.S.; Witt, D.A.; Helgerson, R.N.; Grimes, J.G.; Pritz, P.M.

1980-01-01

Results of the Farmington project area of the Thomas Range-Wasatch detailed geochemical survey are reported. Field and laboratory data are presented for 71 groundwater samples, 345 stream sediment samples, and 178 radiometric readings. Statistical and areal distributions of uranium and possible uranium-related variables are given. A generalized geologic map of the project area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. Uranium concentrations in groundwater range from <0.20 to 21.77 ppB. The highest values are from groundwaters producing from areas in or near the Norwood Tuff and Wasatch, Evanston, and/or Echo Canyon Formations, and the Farmington Canyon Complex. The uranium:boron ratio delineates an anomalous trend associated with the Farmington Canyon Complex. Variables associated with uranium in groundwaters producing from the Norwood Tuff and Wasatch, Evanston, and/or Echo Canyon Formations include the uranium:sulfate ratio, boron, barium, potassium, lithium, silicon, chloride, selenium, and vanadium. Soluble uranium concentrations (U-FL) in stream sediments range from 0.99 to 86.41 ppM. Total uranium concentrations (U-NT) range from 1.60 to 92.40 ppM. Thorium concentrations range from <2 to 47 ppM. Anomalous concentrations of these variables are associated with the Farmington Canyon Complex. Variables which are associated with uranium include cerium, sodium, niobium, phosphorus, titanium, and yttrium

Tissue-phantom dose ratio R(t, F) in irradiation planning. 2

International Nuclear Information System (INIS)

Hegewald, H.

1986-01-01

The principles for measuring doses are represented to complete the developed tissue-phantom dose ratio R(t, F). The functional dependence of the tissue-phantom dose ratio on the field size results from the different spectral energy distribution in the buildup range compared to greater depths. This once more illustrates the demand, to move the calibration and reference depths into greater depths than the dose maximum depth on account of a high precision. The scattering factors and their dependence on the type of collimator are represented and tables are made up for practical use. In a supplement the derivations of the equation systems are given, to find out the tissue-phantom dose ratio by computation and the correspondence is tested. The measurements are more relevant in the megavolt range since dose values typically for the equipment are measured in the buildup range and depth dose tables are not available in the required completeness. (author)

Devonian magmatism in the Timan Range, Arctic Russia - subduction, post-orogenic extension, or rifting?

Science.gov (United States)

Pease, V.; Scarrow, J. H.; Silva, I. G. Nobre; Cambeses, A.

2016-11-01

Devonian mafic magmatism of the northern East European Craton (EEC) has been variously linked to Uralian subduction, post-orogenic extension associated with Caledonian collision, and rifting. New elemental and isotopic analyses of Devonian basalts from the Timan Range and Kanin Peninsula, Russia, in the northern EEC constrain magma genesis, mantle source(s) and the tectonic process(es) associated with this Devonian volcanism to a rift-related context. Two compositional groups of low-K2O tholeiitic basalts are recognized. On the basis of Th concentrations, LREE concentrations, and (LREE/HREE)N, the data suggest two distinct magma batches. Incompatible trace elements ratios (e.g., Th/Yb, Nb/Th, Nb/La) together with Nd and Pb isotopes indicate involvement of an NMORB to EMORB 'transitional' mantle component mixed with variable amounts of a continental component. The magmas were derived from a source that developed high (U,Th)/Pb, U/Th and Sm/Nd over time. The geochemistry of Timan-Kanin basalts supports the hypothesis that the genesis of Devonian basaltic magmatism in the region resulted from local melting of transitional mantle and lower crust during rifting of a mainly non-volcanic continental rifted margin.

Designing double-gap linear accelerators for a wide mass range

International Nuclear Information System (INIS)

Lysenko, W.P.; Wadlinger, E.A.; Rusnak, B.; Krawczyk, F.; Saadatmand, K.; Wan, Z.

1998-01-01

For applications like ion implantation, rf linacs using double-gap structures with external resonators can be used because they are practical at low frequencies. However, since the two gaps associated with a given resonator cannot be individually phased, it is not obvious how to build a linac that can efficiently accelerate particles having different mass/charge ratios. This paper describes the beam dynamics of double-gap rf linacs and shows how to maximize the range of mass/charge ratios. The theory also tells one how to rescale a linac tune (i.e., reset the voltages and phases) so that a new particle, having a different mass or charge, will behave similarly to the original particle

Co-production of acetone and ethanol with molar ratio control enables production of improved gasoline or jet fuel blends.

Science.gov (United States)

Baer, Zachary C; Bormann, Sebastian; Sreekumar, Sanil; Grippo, Adam; Toste, F Dean; Blanch, Harvey W; Clark, Douglas S

2016-10-01

The fermentation of simple sugars to ethanol has been the most successful biofuel process to displace fossil fuel consumption worldwide thus far. However, the physical properties of ethanol and automotive components limit its application in most cases to 10-15 vol% blends with conventional gasoline. Fermentative co-production of ethanol and acetone coupled with a catalytic alkylation reaction could enable the production of gasoline blendstocks enriched in higher-chain oxygenates. Here we demonstrate a synthetic pathway for the production of acetone through the mevalonate precursor hydroxymethylglutaryl-CoA. Expression of this pathway in various strains of Escherichia coli resulted in the co-production of acetone and ethanol. Metabolic engineering and control of the environmental conditions for microbial growth resulted in controllable acetone and ethanol production with ethanol:acetone molar ratios ranging from 0.7:1 to 10.0:1. Specifically, use of gluconic acid as a substrate increased production of acetone and balanced the redox state of the system, predictively reducing the molar ethanol:acetone ratio. Increases in ethanol production and the molar ethanol:acetone ratio were achieved by co-expression of the aldehyde/alcohol dehydrogenase (AdhE) from E. coli MG1655 and by co-expression of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (AdhB) from Z. mobilis. Controlling the fermentation aeration rate and pH in a bioreactor raised the acetone titer to 5.1 g L(-1) , similar to that obtained with wild-type Clostridium acetobutylicum. Optimizing the metabolic pathway, the selection of host strain, and the physiological conditions employed for host growth together improved acetone titers over 35-fold (0.14-5.1 g/L). Finally, chemical catalysis was used to upgrade the co-produced ethanol and acetone at both low and high molar ratios to higher-chain oxygenates for gasoline and jet fuel applications. Biotechnol. Bioeng. 2016;113: 2079-2087. © 2016 Wiley

Forensic utility of the carbon isotope ratio of PVC tape backings

Science.gov (United States)

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

2008-12-01

materials and recycling reactants during manufacture; as a result, tapes may be otherwise physically and chemical indistinguishable, but may have distinct carbon isotope ratios. We compared the carbon isotope ratios of 6 pairs of pre- and post-blast samples of PVC tapes adhered to explosive charges. The carbon isotope ratios of the post-blast samples were 0 to 0.5 ‰ higher than the corresponding pre-blast samples. Possible causes of this carbon isotope increase may be the reaction of the plasticizer and/or adhesive with the PVC backing during the explosion or the addition of debris to the tape backing during the explosion. Even with these minor explosive-induced carbon isotope alterations, the δ13C values of post-blast PVC tape backings were similar enough to the starting material to make carbon isotope ratios of post-blast tape a useful forensic tool. The range of carbon isotope ratios that would be used to exclude potential matches would have to be larger for post-blast samples, but with a 17 ‰ range in the population, this approach may still be useful for post-blast tape samples.

Influence of pollution of boron chlorinity ratio

Digital Repository Service at National Institute of Oceanography (India)

Narvekar, P.V.; Zingde, M.D.

Presence of boron in domestic wastewater has resulted in high B/CI ratio at some locations in the coastal water around Bombay. A widest range (0.215-0.281) of B/CI was observed at a location with high influence of wastewater release. The mean B...

Sensor for mixing ratio of gasoline and alcohol or the like

Energy Technology Data Exchange (ETDEWEB)

Miyata, Shigeru; Matsubara, Yoshihiro

1992-01-14

An improved sensor is disclosed which is capable of continuously measuring a ratio of alcohol and gasoline with high precision, irrespective of the ambient temperature, in order to obtain the most appropriate timing of ignition and injection when employed, for example, in an internal combustion engine. The sensor has a cylindrical enclosure having both inlet and outlet openings to act as a passage through which the liquid fuel mixture flows. A transparent column is concentrically disposed in the enclosure, an outer surface of which is at least in partial contact with the fuel mixture. A light emitting diode is placed at one end of the column so that light from the diode enters the column to reach a boundary between the column and the fuel mixture. A photo diode at the other end of the column receives light beams totally reflected back at the boundary to produce an output, the magnitude of which depends on the mixing ratio of the fuel mixture. A temperature compensation means is also provided in the form of a temperature compensation photo diode and an amplifier, in order to maintain a uniform intensity of light beams emitted from the light emitting diode irrespective of changes in ambient temperature. 8 figs.

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.

Which Bow Shock Theory, Gasdynamic or Magnetohydrodynamic, Better Explains CME Stand-off Distance Ratios from LASCO-C2 Observations ?

Energy Technology Data Exchange (ETDEWEB)

Lee, Jae-Ok; Moon, Y.-J. [School of Space Research Kyung Hee University Yongin 17104 (Korea, Republic of); Lee, Jin-Yi [Department of Astronomy and Space Science Kyung Hee University Yongin 17104 (Korea, Republic of); Kim, R.-S.; Cho, K.-S. [Korea Astronomy and Space Science Institute Daejeon 34055 (Korea, Republic of)

2017-03-20

It is generally believed that fast coronal mass ejections (CMEs) can generate their associated shocks, which are characterized by faint structures ahead of CMEs in white-light coronagraph images. In this study, we examine whether the observational stand-off distance ratio, defined as the CME stand-off distance divided by its radius, can be explained by bow shock theories. Of 535 SOHO /LASCO CMEs (from 1996 to 2015) with speeds greater than 1000 km s{sup −1} and angular widths wider than 60°, we select 18 limb CMEs with the following conditions: (1) their Alfvénic Mach numbers are greater than one under Mann’s magnetic field and Saito’s density distributions; and (2) the shock structures ahead of the CMEs are well identified. We determine observational CME stand-off distance ratios by using brightness profiles from LASCO-C2 observations. We compare our estimates with theoretical stand-off distance ratios from gasdynamic (GD) and magnetohydrodynamic (MHD) theories. The main results are as follows. Under the GD theory, 39% (7/18) of the CMEs are explained in the acceptable ranges of adiabatic gamma ( γ ) and CME geometry. Under the MHD theory, all the events are well explained when we consider quasi-parallel MHD shocks with γ = 5/3. When we use polarized brightness (pB) measurements for coronal density distributions, we also find similar results: 8% (1/12) under GD theory and 100% (12/12) under MHD theory. Our results demonstrate that the bow shock relationships based on MHD theory are more suitable than those based on GD theory for analyzing CME-driven shock signatures.

The isotope systematics of a juvenile intraplate volcano: Pb, Nd, and Srisotope ratios of basalts from Loihi Seamount, Hawaii

International Nuclear Information System (INIS)

Staudigel, H.; Zindler, A.; Leslie, T.

1984-01-01

Sr, Nd, and Pb isotope ratios for a representative suite of 15 basanites, alkali basalts, transitional basalts and tholeiites from Loihi Seamount, Hawaii, display unusually large variations for a single volcano, but lie within known ranges for Hawaiian basalts. Nd isotope ratios in alkali basalts show the largest relative variation (0.51291 - 0.51305), and include the nearly constant tholeiite value (approx.= 0.51297). Pb isotope ratios show similarly large ranges for tholeiites and alkali basalts and continue Tatsumoto's [31] 'Loa' trend towards higher 206 Pb/ 204 Pb, ratios, resulting in a substantial overlap with the 'Kea' trend. 206 Pb/ 204 Pb ratios for Loihi and other volcanoes along the Loa and Kea trends [31] are observed to correlate with the age of the underlying lithosphere suggesting lithosphere involvement in the formation of Hawaiian tholeiites. Loihi lavas display no correlation of Nd, Sr, or Pb isotope ratios with major element compositions or eruptive age, in contrast with observations of some other Hawaiian volcanoes. Isotope data for Loihi, as well as average values for Hawaiian volcanoes, are not adequately explained by previously proposed two-end-member models; new models for the origin and the development of Hawaiian volcanoes must include mixing of at least three geochemically distinct source regions and allow for the involvement of heterogeneous oceanic lithosphere. (orig.)

Species are not most abundant in the centre of their geographic range or climatic niche.

Science.gov (United States)

Dallas, Tad; Decker, Robin R; Hastings, Alan

2017-12-01

The pervasive idea that species should be most abundant in the centre of their geographic range or centre of their climatic niche is a key assumption in many existing ecological hypotheses and has been declared a general macroecological rule. However, empirical support for decreasing population abundance with increasing distance from geographic range or climatic niche centre (distance-abundance relationships) remains fairly weak. We examine over 1400 bird, mammal, fish and tree species to provide a thorough test of distance-abundance relationships, and their associations with species traits and phylogenetic relationships. We failed to detect consistent distance-abundance relationships, and found no association between distance-abundance slope and species traits or phylogenetic relatedness. Together, our analyses suggest that distance-abundance relationships may be rare, difficult to detect, or are an oversimplification of the complex biogeographical forces that determine species spatial abundance patterns. © 2017 John Wiley & Sons Ltd/CNRS.

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

Science.gov (United States)

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

2003-01-01

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

Craniometric ratios of microcephaly and LB1, Homo floresiensis, using MRI and endocasts

Science.gov (United States)

Vannucci, Robert C.; Barron, Todd F.; Holloway, Ralph L.

2011-01-01

The designation of Homo floresiensis as a new species derived from an ancient population is controversial, because the type specimen, LB1, might represent a pathological microcephalic modern Homo sapiens. Accordingly, two specific craniometric ratios (relative frontal breadth and cerebellar protrusion) were ascertained in 21 microcephalic infants and children by using MRI. Data on 118 age-equivalent control (normocephalic) subjects were collected for comparative purposes. In addition, the same craniometric ratios were determined on the endocasts of 10 microcephalic individuals, 79 normal controls (anatomically modern humans), and 17 Homo erectus specimens. These ratios were then compared with those of two LB1 endocasts. The findings showed that the calculated cerebral/cerebellar ratios of the LB1 endocast [Falk D, et al. (2007) Proc Natl Acad Sci USA 104:2513–2518] fall outside the range of living normocephalic individuals. The ratios derived from two LB1 endocasts also fall largely outside the range of modern normal human and H. erectus endocasts and within the range of microcephalic endocasts. The findings support but do not prove the contention that LB1 represents a pathological microcephalic Homo sapiens rather than a new species, (i.e., H. floresiensis). PMID:21825126

Maternal fructose and/or salt intake and reproductive outcome in the rat: effects on growth, fertility, sex ratio, and birth order.

Science.gov (United States)

Gray, Clint; Long, Sophie; Green, Charlotte; Gardiner, Sheila M; Craigon, Jim; Gardner, David S

2013-09-01

Maternal diet can significantly skew the secondary sex ratio away from the expected value of 0.5 (proportion males), but the details of how diet may do this are unclear. Here, we altered dietary levels of salt (4% salt in the feed) and/or fructose (10% in the drinking water) of pregnant rats to model potential effects that consumption of a "Western diet" might have on maternofetal growth, development, and sex ratio. We demonstrate that excess fructose consumption before and during pregnancy lead to a marked skew in the secondary sex ratio (proportion of males, 0.60; P < 0.006). The effect was not mediated by selective developmental arrest of female embryos or influenced by fetal position in the uterine horn or sex-specific effects on sperm motility, suggesting a direct effect of glycolyzable monosaccharide on the maternal ovary and/or ovulated oocyte. Furthermore, combined excess maternal consumption of salt and fructose-sweetened beverage significantly reduced fertility, reflected as a 50% reduction in preimplantation and term litter size. In addition, we also noted birth order effects in the rat, with sequential implantation sites tending to be occupied by the same sex.

Effect of anesthesia, positioning, time, and feeding on the proventriculus: keel ratio of clinically healthy parrots.

Science.gov (United States)

Dennison, Sophie E; Paul-Murphy, Joanne R; Yandell, Brian S; Adams, William M

2010-01-01

Healthy, adult Hispaniolan Amazon parrots (Amazona ventralis) were imaged on three occasions to determine the effects of anesthesia, patient rotation, feeding, and short/long-term temporal factors on the proventriculus:keel ratio. Increasing rotation up to 15 degrees from right lateral resulted in increased inability to measure the proventriculus in up to 44% of birds, meaning that the proventriculus:keel ratio could not be calculated from those radiographs. There was a significant difference between the proventriculus:keel ratio for individual parrots when quantified 3 weeks apart. Despite this difference, all ratios remained within normal limits. No significant effect was identified due to anesthesia, feeding, fasting, or repeated imaging through an 8-h period. Interobserver agreement for measurability and correlation for the proventriculus:keel ratio values was high. It is recommended that the proventriculus:keel ratio be calculated from anesthetized parrots to attain images in true lateral recumbency. Ratio fluctuations within the normal range between radiographs obtained on different dates may be observed in normal parrots.

The sex ratio of offspring is associated with the mothers' age at menarche

DEFF Research Database (Denmark)

Fukuda, Misao; Fukuda, Kiyomi; Shimizu, Takashi

2011-01-01

BACKGROUND Early menarcheal age is a risk factor for breast and ovarian cancers and is also associated with an increased spontaneous abortion rate. The aim of this study was to investigate whether there is a link between early menarcheal age and the offspring sex ratio. METHODS We recorded the sex...... of 21208 live born infants, all singletons, born to 10 847 premenopausal women (mean attending age: 37.5 ± 7.2 years, range 22-54) who attended our clinics for obstetrical and gynaecological assessment. We calculated the sex ratio of newborn infants in relation to the mothers' age of menarche (from 9 to 18...... years) and to the number of infants per woman (i.e. fertility index). RESULTS A low offspring sex ratio (males/females) of 0.800 was observed in mothers who entered menarche at the age of 9 years; the odds ratio (OR) (95% confidence intervals) compared with those of control group with menarche at age 14...

Treatment and Management of Closed or Inactive Small Arms Firing Ranges

National Research Council Canada - National Science Library

Larson, Steven L; Teeter, Cynthia L; Medina, Victor F; Martin, W. A

2007-01-01

This document provides environmental professionals and project managers with information on the effect of range type and soil type on technology selection for one-time cleanup of closed Small Arms Firing Ranges (SAFRs...

Self-produced Time Intervals Are Perceived as More Variable and/or Shorter Depending on Temporal Context in Subsecond and Suprasecond Ranges

Directory of Open Access Journals (Sweden)

Keita eMitani

2016-06-01

Full Text Available The processing of time intervals is fundamental for sensorimotor and cognitive functions. Perceptual and motor timing are often performed concurrently (e.g., playing a musical instrument. Although previous studies have shown the influence of body movements on time perception, how we perceive self-produced time intervals has remained unclear. Furthermore, it has been suggested that the timing mechanisms are distinct for the sub- and suprasecond ranges. Here, we compared perceptual performances for self-produced and passively presented time intervals in random contexts (i.e., multiple target intervals presented in a session across the sub- and suprasecond ranges (Experiment 1 and within the sub- (Experiment 2 and suprasecond (Experiment 3 ranges, and in a constant context (i.e., a single target interval presented in a session in the sub- and suprasecond ranges (Experiment 4. We show that self-produced time intervals were perceived as shorter and more variable across the sub- and suprasecond ranges and within the suprasecond range but not within the subsecond range in a random context. In a constant context, the self-produced time intervals were perceived as more variable in the suprasecond range but not in the subsecond range. The impairing effects indicate that motor timing interferes with perceptual timing. The dependence of impairment on temporal contexts suggests multiple timing mechanisms for the subsecond and suprasecond ranges. In addition, violation of the scalar property (i.e., a constant variability to target interval ratio was observed between the sub- and suprasecond ranges. The violation was clearer for motor timing than for perceptual timing. This suggests that the multiple timing mechanisms for the sub- and suprasecond ranges overlap more for perception than for motor. Moreover, the central tendency effect (i.e., where shorter base intervals are overestimated and longer base intervals are underestimated disappeared with subsecond

Drug ratio-dependent antagonism: a new category of multidrug resistance and strategies for its circumvention.

Science.gov (United States)

Harasym, Troy O; Liboiron, Barry D; Mayer, Lawrence D

2010-01-01

A newly identified form of multidrug resistance (MDR) in tumor cells is presented, pertaining to the commonly encountered resistance of cancer cells to anticancer drug combinations at discrete drug:drug ratios. In vitro studies have revealed that whether anticancer drug combinations interact synergistically or antagonistically can depend on the ratio of the combined agents. Failure to control drug ratios in vivo due to uncoordinated pharmacokinetics could therefore lead to drug resistance if tumor cells are exposed to antagonistic drug ratios. Consequently, the most efficacious drug combination may not occur at the typically employed maximum tolerated doses of the combined drugs if this leads to antagonistic ratios in vivo after administration and resistance to therapeutic effects of the drug combination. Our approach to systematically screen a wide range of drug ratios and concentrations and encapsulate the drug combination in a liposomal delivery vehicle at identified synergistic ratios represents a means to mitigate this drug ratio-dependent MDR mechanism. The in vivo efficacy of the improved agents (CombiPlex formulations) is demonstrated and contrasted with the decreased efficacy when drug combinations are exposed to tumor cells in vivo at antagonistic ratios.

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.

Robust extremum seeking and speed ratio control for high-performance CVT operation

NARCIS (Netherlands)

Meulen, van der S.H.; Jager, de A.G.; Veldpaus, F.E.; Steinbuch, M.

2010-01-01

The variator in a pushbelt continuously variable transmission (CVT) enables a stepless variation of the transmission ratio within a finite range. Nowadays, the variator is electronically controlled and the variator control objectives are twofold: 1) tracking a transmission ratio reference; 2)

Dynamic response of low aspect ratio piezoelectric microcantilevers actuated in different liquid environments

International Nuclear Information System (INIS)

Vázquez, J; Rivera, M A; Hernando, J; Sánchez-Rojas, J L

2009-01-01

The response of commercial piezoelectric AFM probes for potential applications in the field of chemical or biological sensors operating in liquids is investigated using laser Doppler vibrometry. The present work investigates the roles played in the frequency response by the density and the viscosity of different water–glycerol mixtures, in a frequency range of up to 1 MHz in air. Since the width of the tested probes is relatively large (and hence the aspect ratio remains small), inertial loading effects dominate viscous effects, unlike in cantilevers characterized by larger aspect ratios. Measurements are compared with results provided by a simplified computer model of a probe immersed in an inviscid surrounding fluid

Characterization and immobilization of engineered sialidases from Trypanosoma rangeli for transsialylation

DEFF Research Database (Denmark)

Zeuner, Birgitte; González-Delgado, Isabel; Holck, Jesper

2017-01-01

transsialylation activity: both had a 14 times higher ratio between transsialylation and hydrolysis products compared to the first reported mutant TrSA5mut. In the current work, these two variants, Tr15 and Tr16, were characterized in terms of pH optimum, thermal stability, effect of acceptor-to-donor ratio......, and acceptor specificity for transsialylation using casein glycomacropeptide (CGMP) as sialyl donor and lactose or other human milk oligosaccharide core structures as acceptors. Both sialidase variants exhibited pH optima around pH 4.8. Thermal stability of each enzyme was comparable to that of previously...... developed T. rangeli sialidase variants and higher than that of the native transsialidase from T. cruzi (TcTS). As for other engineered T. rangeli sialidase variants and TcTS, the acceptor specificity was broad: lactose, galactooligosaccharides (GOS), xylooligosaccharides (XOS), and human milk...

Stable carbon isotope ratio profiling of illicit testosterone preparations--domestic and international seizures.

Science.gov (United States)

Brooker, Lance; Cawley, Adam; Drury, Jason; Edey, Claire; Hasick, Nicole; Goebel, Catrin

2014-10-01

Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is now established as a robust and mature analytical technique for the doping control of endogenous anabolic androgenic steroids in human sport. It relies on the assumption that the carbon isotope ratios of naturally produced steroids are significantly different to synthetically manufactured testosterone or testosterone prohormones used in commercial medical or dietary supplement products. Recent publications in this journal have highlighted the existence of black market testosterone preparations with carbon isotope ratios within the range reported for endogenous steroids (i.e. δ(13) C ≥ -25.8 ‰). In this study, we set out to profile domestic and international law enforcement seizures of illicit testosterone products to monitor the prevalence of 'enriched' substrates--which if administered to human subjects would be considered problematic for the use of current GC-C-IRMS methodologies for the doping control of testosterone in sport. The distribution of δ(13) C values for this illicit testosterone sample population (n = 283) ranged from -23.4 ‰ to -32.9 ‰ with mean and median of -28.6 ‰--comparable to previous work. However, only 13 out of 283 testosterone samples (4.6 %) were found to display δ(13) C values ≥ -25.8 ‰, confirming that in the vast majority of cases of illicit testosterone administration, current GC-C-IRMS doping control procedures would be capable of confirming misuse. Copyright © 2014 John Wiley & Sons, Ltd.

BINARY FORMATION MECHANISMS: CONSTRAINTS FROM THE COMPANION MASS RATIO DISTRIBUTION

International Nuclear Information System (INIS)

Reggiani, Maddalena M.; Meyer, Michael R.

2011-01-01

We present a statistical comparison of the mass ratio distribution of companions, as observed in different multiplicity surveys, to the most recent estimate of the single-object mass function. The main goal of our analysis is to test whether or not the observed companion mass ratio distribution (CMRD) as a function of primary star mass and star formation environment is consistent with having been drawn from the field star initial mass function (IMF). We consider samples of companions for M dwarfs, solar-type stars, and intermediate-mass stars, both in the field as well as clusters or associations, and compare them with populations of binaries generated by random pairing from the assumed IMF for a fixed primary mass. With regard to the field we can reject the hypothesis that the CMRD was drawn from the IMF for different primary mass ranges: the observed CMRDs show a larger number of equal-mass systems than predicted by the IMF. This is in agreement with fragmentation theories of binary formation. For the open clusters α Persei and the Pleiades we also reject the IMF random-pairing hypothesis. Concerning young star-forming regions, currently we can rule out a connection between the CMRD and the field IMF in Taurus but not in Chamaeleon I. Larger and different samples are needed to better constrain the result as a function of the environment. We also consider other companion mass functions and we compare them with observations. Moreover the CMRD both in the field and clusters or associations appears to be independent of separation in the range covered by the observations. Combining therefore the CMRDs of M (1-2400 AU) and G (28-1590 AU) primaries in the field and intermediate-mass primary binaries in Sco OB2 (29-1612 AU) for mass ratios, q = M 2 /M 1 , from 0.2 to 1, we find that the best chi-square fit follows a power law dN/dq∝q β , with β = -0.50 ± 0.29, consistent with previous results. Finally, we note that the Kolmogorov-Smirnov test gives a ∼1

Interannual Variability of Fisheries Economic Returns and Energy Ratios Is Mostly Explained by Gear Type

Science.gov (United States)

Trenkel, Verena M.; Daurès, Fabienne; Rochet, Marie-Joëlle; Lorance, Pascal

2013-01-01

According to portfolio theory applied to fisheries management, economic returns are stabilised by harvesting in a portfolio stocks of species whose returns are negatively correlated and for which the portfolio economic return variance is smaller than the sum of stock specific return variances. Also, variability is expected to decrease with portfolio width. Using a range of indicators, these predictions were tested for the French fishing fleets in the Bay of Biscay (Northeast Atlantic) during the period 2001–2009. For this, vessels were grouped into eight fishing fleets based on the gears used and exploited species were grouped into five functional groups. The portfolio width of fleets ranged from 1–3 functional groups, or 4–19 species. Economic fleet returns (sale revenues minus fishing costs) varied strongly between years; the interannual variability was independent of portfolio width (species or functional groups). Energy ratio expressed by the ratio between fuel energy used for fishing and energy contained in landings varied from 0.3 for purse seines to 9.7 for trawlers using bottom trawls alone or in combination with pelagic trawls independent of portfolio width. Interannual variability in total sale revenues was larger than the sum of species specific sales revenue variability, except for fleets using hooks and pelagic trawlers; it increased with the number of species exploited. In conclusion, the interannual variability of economic returns or energy ratios of French fisheries in the Bay of Biscay did not decrease with the number of species or functional groups exploited, though it varied between fleets. PMID:23922951

Long-Term Statin Administration Does Not Affect Warfarin Time in Therapeutic Range in Australia or Singapore

Directory of Open Access Journals (Sweden)

Nijole Bernaitis

2018-05-01

Full Text Available Background: Warfarin requires ongoing monitoring of the International Normalised Ratio (INR. This is because numerous factors influence the response, including drug interactions with commonly-prescribed medications, such as statins. The administration of statins with warfarin may change INR; however, there is limited information regarding the effects on warfarin control as measured by time in therapeutic range (TTR. Statins may also alter bleeds with warfarin, but there are conflicting reports demonstrating both increased and decreased bleeds, and limited data on diverse ethnic populations. Therefore, the aim of this study was to determine the effect of statin administration on warfarin control and bleeds in patients in Australia and Singapore. Methods: Retrospective data were collected for patients on warfarin between January and June 2014 in Australia and Singapore. Patient data were used to calculate TTR and bleed events. Concurrent statin therapy was assessed and comparisons of TTR and bleed incidence were made across patient subgroups. Results: Warfarin control in Australia and Singapore was not significantly affected by statins, as measured by TTR (83% and 58%, respectively, frequency of testing, and warfarin doses. In Australia, statin use did not significantly affect bleeds, whilst in Singapore the bleed incidence was significantly lower for patients on statins. Conclusions: Chronic concurrent administration of statins with warfarin does not adversely affect warfarin TTR in Australia or Singapore. In Singapore, patients on statins, compared to no statins, had a lower bleed incidence and this requires further investigation, especially given the potential genetic influences of ethnicity on both statin and warfarin metabolism.

On the range of validity of the dipole picture

International Nuclear Information System (INIS)

Ewerz, Carlo; Manteuffel, Andreas von; Nachtmann, Otto

2008-01-01

We derive correlated bounds on ratios of deep inelastic structure functions from the dipole picture of photon-hadron scattering at high energies. In particular we consider ratios of the longitudinal structure function, the total structure function, and the charm part of the latter. We also consider ratios of total structure functions taken at the same energy but at three different photon virtualities. It is shown that by confronting these bounds with experimental data we can significantly constrain the range of validity of the dipole picture.

The net effect of alternative allocation ratios on recruitment time and trial cost.

Science.gov (United States)

Vozdolska, Ralitza; Sano, Mary; Aisen, Paul; Edland, Steven D

2009-04-01

Increasing the proportion of subjects allocated to the experimental treatment in controlled clinical trials is often advocated as a method of increasing recruitment rates and improving the performance of trials. The presumption is that the higher likelihood of randomization to the experimental treatment will be perceived by potential study enrollees as an added benefit of participation and will increase recruitment rates and speed the completion of trials. However, studies with alternative allocation ratios require a larger sample size to maintain statistical power, which may result in a net increase in time required to complete recruitment and a net increase in total trial cost. To describe the potential net effect of alternative allocation ratios on recruitment time and trial cost. Models of recruitment time and trial cost were developed and used to compare trials with 1:1 allocation to trials with alternative allocation ratios under a range of per subject costs, per day costs, and enrollment rates. In regard to time required to complete recruitment, alternative allocation ratios are net beneficial if the recruitment rate improves by more than about 4% for trials with a 1.5:1 allocation ratio and 12% for trials with a 2:1 allocation ratio. More substantial improvements in recruitment rate, 13 and 47% respectively for scenarios we considered, are required for alternative allocation to be net beneficial in terms of tangible monetary cost. The cost models were developed expressly for trials comparing proportions or means across treatment groups. Using alternative allocation ratio designs to improve recruitment may or may not be time and cost-effective. Using alternative allocation for this purpose should only be considered for trial contexts where there is both clear evidence that the alternative design does improve recruitment rates and the attained time or cost efficiency justifies the added study subject burden implied by a larger sample size.

Colloid normalizes resuscitation ratio in pediatric burns.

Science.gov (United States)

Faraklas, Iris; Lam, Uyen; Cochran, Amalia; Stoddard, Gregory; Saffle, Jeffrey

2011-01-01

Fluid resuscitation of burned children is challenging because of their small size and intolerance to over- or underresuscitation. Our American Burn Association-verified regional burn center has used colloid "rescue" as part of our pediatric resuscitation protocol. With Institutional Review Board approval, the authors reviewed children with ≥15% TBSA burns admitted from January 1, 2004, to May 1, 2009. Resuscitation was based on the Parkland formula, which was adjusted to maintain urine output. Patients requiring progressive increases in crystalloid were placed on a colloid protocol. Results were expressed as an hourly resuscitation ratio (I/O ratio) of fluid infusion (ml/kg/%TBSA/hr) to urine output (ml/kg/hr). We reviewed 53 patients; 29 completed resuscitation using crystalloid alone (lactated Ringer's solution [LR]), and 24 received colloid supplementation albumin (ALB). Groups were comparable in age, gender, weight, and time from injury to admission. ALB patients had more inhalation injuries and larger total and full-thickness burns. LR patients maintained a median I/O of 0.17 (range, 0.08-0.31), whereas ALB patients demonstrated escalating ratios until the institution of albumin produced a precipitous return of I/O comparable with that of the LR group. Hospital stay was lower for LR patients than ALB patients (0.59 vs 1.06 days/%TBSA, P = .033). Twelve patients required extremity or torso escharotomy, but this did not differ between groups. There were no decompressive laparotomies. The median resuscitation volume for ALB group was greater than LR group (9.7 vs 6.2 ml/kg/%TBSA, P = .004). Measuring hourly I/O is a helpful means of evaluating fluid demands during burn shock resuscitation. The addition of colloid restores normal I/O in pediatric patients.

Using Approximate Bayesian Computation to infer sex ratios from acoustic data.

Science.gov (United States)

Lehnen, Lisa; Schorcht, Wigbert; Karst, Inken; Biedermann, Martin; Kerth, Gerald; Puechmaille, Sebastien J

2018-01-01

Population sex ratios are of high ecological relevance, but are challenging to determine in species lacking conspicuous external cues indicating their sex. Acoustic sexing is an option if vocalizations differ between sexes, but is precluded by overlapping distributions of the values of male and female vocalizations in many species. A method allowing the inference of sex ratios despite such an overlap will therefore greatly increase the information extractable from acoustic data. To meet this demand, we developed a novel approach using Approximate Bayesian Computation (ABC) to infer the sex ratio of populations from acoustic data. Additionally, parameters characterizing the male and female distribution of acoustic values (mean and standard deviation) are inferred. This information is then used to probabilistically assign a sex to a single acoustic signal. We furthermore develop a simpler means of sex ratio estimation based on the exclusion of calls from the overlap zone. Applying our methods to simulated data demonstrates that sex ratio and acoustic parameter characteristics of males and females are reliably inferred by the ABC approach. Applying both the ABC and the exclusion method to empirical datasets (echolocation calls recorded in colonies of lesser horseshoe bats, Rhinolophus hipposideros) provides similar sex ratios as molecular sexing. Our methods aim to facilitate evidence-based conservation, and to benefit scientists investigating ecological or conservation questions related to sex- or group specific behaviour across a wide range of organisms emitting acoustic signals. The developed methodology is non-invasive, low-cost and time-efficient, thus allowing the study of many sites and individuals. We provide an R-script for the easy application of the method and discuss potential future extensions and fields of applications. The script can be easily adapted to account for numerous biological systems by adjusting the type and number of groups to be

Enhancement of concentration range of chromatographically detectable components with array detector mass spectrometry

Science.gov (United States)

Enke, Christie

2013-02-19

Methods and instruments for high dynamic range analysis of sample components are described. A sample is subjected to time-dependent separation, ionized, and the ions dispersed with a constant integration time across an array of detectors according to the ions m/z values. Each of the detectors in the array has a dynamically adjustable gain or a logarithmic response function, producing an instrument capable of detecting a ratio of responses or 4 or more orders of magnitude.

Obesity Index That Better Predict Metabolic Syndrome: Body Mass Index, Waist Circumference, Waist Hip Ratio, or Waist Height Ratio

Directory of Open Access Journals (Sweden)

Abdulbari Bener

2013-01-01

Full Text Available Aim. The aim was to compare body mass index (BMI, waist circumference (WC, waist hip ratio (WHR, and waist height ratio (WHtR to identify the best predictor of metabolic syndrome (MetS among Qatari adult population. Methods. A cross-sectional survey from April 2011 to December 2012. Data was collected from 1552 participants followed by blood sampling. MetS was defined according to Third Adult Treatment Panel (ATPIII and International Diabetes Federation (IDF. Receiver operating characteristics (ROC curve analysis was performed. Results. Among men, WC followed by WHR and WHtR yielded the highest area under the curve (AUC (0.78; 95% CI 0.74–0.82 and 0.75; 95% CI 0.71–0.79, resp.. Among women, WC followed by WHtR yielded the highest AUC (0.81; 95% CI 0.78–0.85 & 0.79; 95% CI 0.76–0.83, resp.. Among men, WC at a cut-off 99.5 cm resulted in the highest Youden index with sensitivity 81.6% and 63.9% specificity. Among women, WC at a cut-off 91 cm resulted in the highest Youden index with the corresponding sensitivity and specificity of 86.5% and 64.7%, respectively. BMI had the lowest sensitivity and specificity in both genders. Conclusion. WC at cut-off 99.5 cm in men and 91 cm in women was the best predictor of MetS in Qatar.

Predictive value of glucose-insulin ratio in PCOS and profile of women who will benefit from metformin therapy: obese, lean, hyper or normoinsulinemic?

Science.gov (United States)

Onalan, Gogsen; Goktolga, Umit; Ceyhan, Temel; Bagis, Tayfun; Onalan, Reside; Pabuçcu, Recai

2005-12-01

The aim of the present study is to evaluate sub-groups of PCOS patients who will benefit from metformin therapy and to find out any predictors of ovulation in PCOS sub-groups. In the current prospective-randomized, placebo-controlled, double-blind study, PCOS patients (n = 116) were divided into six main groups according to glucose to insulin ratio (G-I ratio mg/10(-4) U) and body mass index (BMI kg/m2) as: Group 1: normoinsulinemic (G-I ratio > or = 4.5 mg/10(-4) U), lean (BMI or = 30) (n = 18); Group 4: hyperinsulinemic (G-I ratio lean (n = 28); Group 5: hyperinsulinemic, overweight (n = 17); Group 6: hyperinsulinemic, obese (n = 20). Patients in each group were randomized onto placebo or metformin treatments (850 mg two to three times per day according to BMI). The rate of ovulation, biochemical profile, hormonal profile and clinical symptoms of hyperandrogenism were evaluated before and after 6 months of metformin and placebo treatments. We observed a significant decrease in WHR following metformin therapy in the normoinsulinemic overweight sub-group (P lean women (P lean hyperinsulinemic and normoinsulinemic groups (P lean hyperinsulinemic women (P PCOS patients.

The male handicap: male-biased mortality explains skewed sex ratios in brown trout embryos.

Science.gov (United States)

Morán, P; Labbé, L; Garcia de Leaniz, C

2016-12-01

Juvenile sex ratios are often assumed to be equal for many species with genetic sex determination, but this has rarely been tested in fish embryos due to their small size and absence of sex-specific markers. We artificially crossed three populations of brown trout and used a recently developed genetic marker for sexing the offspring of both pure and hybrid crosses. Sex ratios (SR = proportion of males) varied widely one month after hatching ranging from 0.15 to 0.90 (mean = 0.39 ± 0.03). Families with high survival tended to produce balanced or male-biased sex ratios, but SR was significantly female-biased when survival was low, suggesting that males sustain higher mortality during development. No difference in SR was found between pure and hybrid families, but the existence of sire × dam interactions suggests that genetic incompatibility may play a role in determining sex ratios. Our findings have implications for animal breeding and conservation because skewed sex ratios will tend to reduce effective population size and bias selection estimates. © 2016 The Authors.

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.

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.

Effect of natural and laboratory diet on O : N ratio in juvenile lobsters (Homarus americanus).

Science.gov (United States)

Brown, Anne Christine

2006-05-01

Oxygen consumption and ammonia excretion rates of juvenile lobsters spanning the size range from shelter-restricted to vagile (7-60 mm CL, carapace length) were measured. There are no significant size-dependent break points in the slope of oxygen consumption or nitrogen excretion rates versus weight in freshly caught wild or laboratory fed lobsters. This suggests that there are no inherent changes in energy metabolism in juvenile lobster in the 7-60 mm CL range (stage V to adolescent lobsters), despite major behavioral shifts related to foraging and shelter use. In addition, the O : N ratio of freshly caught wild lobsters (15.7+/-7.4, mean+/-S.D.) is not significantly different from that of lobsters fed brown algae (13.4+/-4.9) or a mixed carbohydrate/protein diet (13.7+/-6.8) in lab. The O : N ratio of wild lobsters is significantly higher than lobsters fed a high protein diet (7.5+/-2.5) in the lab. This suggests that carbohydrates, particularly algal-derived carbohydrates, make up a significant portion of the metabolic fuel of wild juvenile lobsters from settlement through adolescence.

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules.

Science.gov (United States)

Foster, T A; Hackenberg, T D; Vaidya, M

2001-09-01

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.

Polarization ratio property and material classification method in passive millimeter wave polarimetric imaging

Science.gov (United States)

Cheng, Yayun; Qi, Bo; Liu, Siyuan; Hu, Fei; Gui, Liangqi; Peng, Xiaohui

2016-10-01

Polarimetric measurements can provide additional information as compared to unpolarized ones. In this paper, linear polarization ratio (LPR) is created to be a feature discriminator. The LPR properties of several materials are investigated using Fresnel theory. The theoretical results show that LPR is sensitive to the material type (metal or dielectric). Then a linear polarization ratio-based (LPR-based) method is presented to distinguish between metal and dielectric materials. In order to apply this method to practical applications, the optimal range of incident angle have been discussed. The typical outdoor experiments including various objects such as aluminum plate, grass, concrete, soil and wood, have been conducted to validate the presented classification method.

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

Science.gov (United States)

Stickel, L.F.

1949-01-01

females for egg laying. Trips of unexplained nature are made by both males and females. Turtles from other areas are occasional transients through the study plot. Standardized census trips provided data for estimating the size of the population. Census data were taken after females had returned from egg laying. The samples were spaced at intervals of a week or more to allow free movement of turtles over their ranges and assure more nearly equal availability of all turtles. These standard samples were compared by a collection ratio. Assumptions involved in the use of this ratio are discussed. Correction factors were applied to make allowance for turtles whose ranges.were partly inside and partly outside the study area, and for transient turtles. A second estimate, on the basis of the entire season's collecting, gave closely comparable results. The population of the study area is estimated to be between four and five turtles per acre, with juveniles constituting less than ten per cent of the total.

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.

The Measurement of Fuel-Air Ratio by Analysis for the Oxidized Exhaust Gas

Science.gov (United States)

Gerrish, Harold C.; Meem, J. Lawrence, Jr.

1943-01-01

An investigation was made to determine a method of measuring fuel-air ratio that could be used for test purposes in flight and for checking conventional equipment in the laboratory. Two single-cylinder test engines equipped with typical commercial engine cylinders were used. The fuel-air ratio of the mixture delivered to the engines was determined by direct measurement of the quantity of air and of fuel supplied and also by analysis of the oxidized exhaust gas and of the normal exhaust gas. Five fuels were used: gasoline that complied with Army-Navy fuel Specification No. AN-VV-F-781 and four mixtures of this gasoline with toluene, benzene, and xylene. The method of determining the fuel-air ratio described in this report involves the measurement of the carbon-dioxide content of the oxidized exhaust gas and the use of graphs for the presented equation. This method is considered useful in aircraft, in the field, or in the laboratory for a range of fuel-air ratios from 0.047 to 0.124.

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)

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.

Morphologic and cytochemical characteristics of blood cells and hematologic and plasma biochemical reference ranges in green iguanas.

Science.gov (United States)

Harr, K E; Alleman, A R; Dennis, P M; Maxwell, L K; Lock, B A; Bennett, R A; Jacobson, E R

2001-03-15

To determine blood cell morphologic characteristics and hematologic and plasma biochemical reference ranges for iguanas housed in a warm indoor and outdoor environment with regular exposure to direct sunlight. Original study. 51 clinically normal iguanas (18 males, 25 females, and 8 juveniles) housed in 3 Florida locations. Blood was collected from the coccygeal or ventral abdominal vein. Any samples that had obvious hemolysis or clot formation were not used. Leukocyte counts were determined manually; other hematologic values were obtained by use of a commercially available cell counter. Plasma biochemical values were determined by use of a spectrophotometric chemistry analyzer. Blood smears were stained with Wright-Giemsa and cytochemical stains for morphologic and cytochemical evaluation. Hematologic ranges were generally higher in this study than previously reported. Thrombocytes were variable in appearance between individuals and sometimes difficult to distinguish from lymphocytes on a Wright-Giemsa preparation. Concentrations of calcium, phosphorus, total protein, globulins, and cholesterol were significantly higher, and the albumin:globulin ratio was significantly lower, in healthy gravid females than in male or nongravid female iguanas. Nongravid females had significantly higher calcium and cholesterol concentrations, compared with males. The calcium:phosphorus ratio was > 1 in all iguanas. Gravid females had a calcium phosphorus product ranging between 210 and 800. Intracytoplasmic inclusions were identified within the erythrocytes of some iguanas. Hematologic ranges for iguanas in this study are higher than those reported for iguanas. Sex and age of the iguana should be considered when evaluating biochemical values. Healthy ovulating and gravid females may have significantly increased electrolyte and protein concentrations, but maintain a calcium:phosphorus ratio > 1.

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...

Temperature and air-fuel ratio dependent specific heat ratio functions for lean burned and unburned mixture

International Nuclear Information System (INIS)

Ceviz, M.A.; Kaymaz, I.

2005-01-01

The most important thermodynamic property used in heat release calculations for engines is the specific heat ratio. The functions proposed in the literature for the specific heat ratio are temperature dependent and apply at or near stoichiometric air-fuel ratios. However, the specific heat ratio is also influenced by the gas composition in the engine cylinder and especially becomes important for lean combustion engines. In this study, temperature and air-fuel ratio dependent specific heat ratio functions were derived to minimize the error by using an equilibrium combustion model for burned and unburned mixtures separately. After the error analysis between the equilibrium combustion model and the derived functions is presented, the results of the global specific heat ratio function, as varying with mass fraction burned, were compared with the proposed functions in the literature. The results of the study showed that the derived functions are more feasible at lean operating conditions of a spark ignition engine

Super-ranging. A new ranging strategy in European badgers.

Directory of Open Access Journals (Sweden)

Aoibheann Gaughran

Full Text Available We monitored the ranging of a wild European badger (Meles meles population over 7 years using GPS tracking collars. Badger range sizes varied seasonally and reached their maximum in June, July and August. We analysed the summer ranging behaviour, using 83 home range estimates from 48 individuals over 6974 collar-nights. We found that while most adult badgers (males and females remained within their own traditional social group boundaries, several male badgers (on average 22% regularly ranged beyond these traditional boundaries. These adult males frequently ranged throughout two (or more social group's traditional territories and had extremely large home ranges. We therefore refer to them as super-rangers. While ranging across traditional boundaries has been recorded over short periods of time for extraterritorial mating and foraging forays, or for pre-dispersal exploration, the animals in this study maintained their super-ranges from 2 to 36 months. This study represents the first time such long-term extra-territorial ranging has been described for European badgers. Holding a super-range may confer an advantage in access to breeding females, but could also affect local interaction networks. In Ireland & the UK, badgers act as a wildlife reservoir for bovine tuberculosis (TB. Super-ranging may facilitate the spread of disease by increasing both direct interactions between conspecifics, particularly across social groups, and indirect interactions with cattle in their shared environment. Understanding super-ranging behaviour may both improve our understanding of tuberculosis epidemiology and inform future control strategies.

Thyroid Function Within the Normal Range and Risk of Coronary Heart Disease

DEFF Research Database (Denmark)

Åsvold, Bjørn O; Vatten, Lars J; Bjøro, Trine

2015-01-01

documented, but conflicting evidence suggests that thyrotropin levels in the upper part of the reference range may be associated with an increased risk of coronary heart disease (CHD). OBJECTIVE: To assess the association between differences in thyroid function within the reference range and CHD risk. DESIGN...... known thyroid or cardiovascular disease at baseline. EXPOSURES: Thyroid function as expressed by serum thyrotropin levels at baseline. MAIN OUTCOMES AND MEASURES: Hazard ratios (HRs) of CHD mortality and CHD events according to thyrotropin levels after adjustment for age, sex, and smoking status....... This finding suggests that differences in thyroid function within the population reference range do not influence the risk of CHD. Increased CHD risk does not appear to be a reason for lowering the upper thyrotropin reference limit....

General applicability of synthetic gene-overexpression for cell-type ratio control via reprogramming.

Science.gov (United States)

Ishimatsu, Kana; Hata, Takashi; Mochizuki, Atsushi; Sekine, Ryoji; Yamamura, Masayuki; Kiga, Daisuke

2014-09-19

Control of the cell-type ratio in multistable systems requires wide-range control of the initial states of cells. Here, using a synthetic circuit in E. coli, we describe the use of a simple gene-overexpression system combined with a bistable toggle switch, for the purposes of enabling the wide-range control of cellular states and thus generating arbitrary cell-type ratios. Theoretically, overexpression induction temporarily alters the bistable system to a monostable system, in which the location of the single steady state of cells can be manipulated over a wide range by regulating the overexpression levels. This induced cellular state becomes the initial state of the basal bistable system upon overexpression cessation, which restores the original bistable system. We experimentally demonstrated that the overexpression induced a monomodal cell distribution, and subsequent overexpression withdrawal generated a bimodal distribution. Furthermore, as designed theoretically, regulating the overexpression levels by adjusting the concentrations of small molecules generated arbitrary cell-type ratios.

Do voluntary strength, proprioception, range of motion, or postural sway predict occurrence of lateral ankle sprain?

OpenAIRE

de Noronha, M; Refshauge, K M; Herbert, R D; Kilbreath, S L

2006-01-01

Prevention of ankle sprain, the most common sporting injury, is only possible once risk factors have been identified. Voluntary strength, proprioception, postural sway, and range of motion are possible risk factors. A systematic review was carried out to investigate these possiblities. Eligible studies were those with longitudinal design investigating ankle sprain in subjects aged ⩾15 years. The studies had to have measured range of motion, voluntary strength, proprioception, or postural sway...

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.

Effect of Subject Rotation on Assessment of Esthetic Dental Ratios: A Simulation Study

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Rajesh Gyawali

2016-01-01

Full Text Available Objective. This study aimed to find out the change in esthetic ratios during rotation of patient’s head using a simulation. Materials and Methods. A plaster study model was photographed placing its midline along the long axis of the camera. Then a series of photographs were taken by rotating the model each degree till 10° on both right and left sides. These photographs were digitally measured and the ratio of the maxillary anterior teeth at zero-degree rotation was compared with that at various degrees of rotation. Results. As the model was rotated to the right side till 10°, the ratio of the right lateral to central incisor gradually decreased while the ratio of the left lateral to central incisor gradually increased. However, the ratio of the canine to lateral incisor on both sides gradually increased. Similar results were obtained when the model was rotated to the left side. The ratio of the lateral to central incisor deviated from the acceptable range (±10% when there was rotation of more than 7°, whereas the ratio of the canine to lateral incisor was within the acceptable range till 10° rotation on either side. Conclusions. Rotation of the model by more than 7° leads to a substantial change in the esthetic ratio.

Relationship of otolith strontium-to-calcium ratios and salinity: Experimental validation for juvenile salmonids

Science.gov (United States)

Zimmerman, C.E.

2005-01-01

Analysis of otolith strontium (Sr) or strontium-to-calcium (Sr:Ca) ratios provides a powerful tool to reconstruct the chronology of migration among salinity environments for diadromous salmonids. Although use of this method has been validated by examination of known individuals and translocation experiments, it has never been validated under controlled experimental conditions. In this study, incorporation of otolith Sr was tested across a range of salinities and resulting levels of ambient Sr and Ca concentrations in juvenile chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), sockeye salmon (Oncorhynchus nerka), rainbow trout (Oncorhynchus rnykiss), and Arctic char (Salvelinus alpinus). Experimental water was mixed, using stream water and seawater as end members, to create experimental salinities of 0.1, 6.3, 12.7, 18.6, 25.5, and 33.0 psu. Otolith Sr and Sr:Ca ratios were significantly related to salinity for all species (r2 range: 0.80-0.91) but provide only enough predictive resolution to discriminate among fresh water, brackish water, and saltwater residency. These results validate the use of otolith Sr:Ca ratios to broadly discriminate salinity histories encountered by salmonids but highlight the need for further research concerning the influence of osmoregulation and physiological changes associated with smoking on otolith microchemistry.

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

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

Science.gov (United States)

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

2018-04-01

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

Strain ratio measurement of femoral cartilage by real-time elastosonography: preliminary results

International Nuclear Information System (INIS)

Ipek, Ali; Unal, Ozlem; Kartal, Merve Gulbiz; Arslan, Halil; Isik, Cetin; Bozkurt, Murat

2015-01-01

The purpose of this study was to evaluate strain ratio measurement of femoral cartilage using real-time elastosonography. Twenty-five patients with femoral cartilage pathology on MRI (study group) were prospectively compared with 25 subjects with normal findings on MRI (control group) using real-time elastosonography. Strain ratio measurements of pathologic and normal cartilage were performed and compared, both within the study group and between the two groups. Elastosonography colour-scale coding showed a colour change from blue to red in pathologic cartilage and only blue colour-coding in normal cartilage. In the study group, the median strain ratio was higher in pathologic cartilage areas compared to normal areas (median, 1.49 [interquartile range, 0.80-2.53] vs. median, 0.01 [interquartile range, 0.01-0.01], p < 0.001, respectively). The median strain ratio of the control group was 0.01 (interquartile range, 0.01-0.01), and there was no significant difference compared to normal areas of the study group. There was, however, a significant difference between the control group cartilage and pathologic cartilage of the study group (p < 0.001). Elastosonography may be an effective, easily accessible, and relatively simple tool to demonstrate pathologic cartilage and to differentiate it from normal cartilage in the absence of advanced imaging facility such as MRI. (orig.)

Branching ratios in the radiative decay of helium doubly excited states

International Nuclear Information System (INIS)

Coreno, M.; Prince, K. C.; Richter, R.; De Simone, M.; Bucar, K.; Zitnik, M.

2005-01-01

The doubly excited singlet states of He below the N=2 threshold may decay by autoionization or fluorescence. In the fluorescence decay channel, most decay cascades consist of emission of three photons, of which the first is a VUV photon, the second is in or near the visible range, and the last is another VUV photon. We have studied the fluorescence channel decay dynamics of the (2,0 n ) (2,1 n ) and (2,-1 n ) 1 P, n=3-7, states by wavelength dispersed photon-induced fluorescence spectroscopy. We have detected the photons in the second step of the cascade and determined the branching ratios for the strongest lines in this step. From these data we are able to calculate the branching ratios of the first step in the cascade. The results are in good agreement with calculations of the main decay channels of the higher resonances, but about 20-30 % lower, and so we are able to describe quantitatively the whole fluorescence cascade of the above-mentioned doubly excited states

Numerical Investigation on Fluid Flow in a 90-Degree Curved Pipe with Large Curvature Ratio

Directory of Open Access Journals (Sweden)

Yan Wang

2015-01-01

Full Text Available In order to understand the mechanism of fluid flows in curved pipes, a large number of theoretical and experimental researches have been performed. As a critical parameter of curved pipe, the curvature ratio δ has received much attention, but most of the values of δ are very small (δ<0.1 or relatively small (δ≤0.5. As a preliminary study and simulation this research studied the fluid flow in a 90-degree curved pipe of large curvature ratio. The Detached Eddy Simulation (DES turbulence model was employed to investigate the fluid flows at the Reynolds number range from 5000 to 20000. After validation of the numerical strategy, the pressure and velocity distribution, pressure drop, fluid flow, and secondary flow along the curved pipe were illustrated. The results show that the fluid flow in a curved pipe with large curvature ratio seems to be unlike that in a curved pipe with small curvature ratio. Large curvature ratio makes the internal flow more complicated; thus, the flow patterns, the separation region, and the oscillatory flow are different.

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

Science.gov (United States)

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

2018-02-01

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

A test of the mean density approximation for Lennard-Jones mixtures with large size ratios

International Nuclear Information System (INIS)

Ely, J.F.

1986-01-01

The mean density approximation for mixture radial distribution functions plays a central role in modern corresponding-states theories. This approximation is reasonably accurate for systems that do not differ widely in size and energy ratios and which are nearly equimolar. As the size ratio increases, however, or if one approaches an infinite dilution of one of the components, the approximation becomes progressively worse, especially for the small molecule pair. In an attempt to better understand and improve this approximation, isothermal molecular dynamics simulations have been performed on a series of Lennard-Jones mixtures. Thermodynamic properties, including the mixture radial distribution functions, have been obtained at seven compositions ranging from 5 to 95 mol%. In all cases the size ratio was fixed at two and three energy ratios were investigated, 22 / 11 =0.5, 1.0, and 1.5. The results of the simulations are compared with the mean density approximation and a modification to integrals evaluated with the mean density approximation is proposed

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.

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

Science.gov (United States)

Hartman, Gideon; Richards, Mike

2014-02-01

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

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)

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...

The assumption of linearity in soil and plant concentration ratios: an experimental evaluation

International Nuclear Information System (INIS)

Sheppard, S.C.; Evenden, W.G.

1988-01-01

We have evaluated one of the main assumptions in the use of concentration ratios to describe the transfer of elements in the environment. The ratios examined in detail were the 'concentration ratio' (CR) of leaf to soil and the 'partition coefficient' (Ksub(d)) of solid- to liquid-phase concentrations in soil. Use of these ratios implies a linear relationship between the concentrations. Soil was experimentally contaminated to evaluate this linearity over more than a 1000-fold range in concentration. A secondary objective was to determine CR and Ksub(d) values in a long-term (2 y) outdoor study using a peat soil and blueberries. The elements I, Se, Cs, Pb and U were chosen as environmentally important elements. The results indicated that relationships of leaf and leachate concentrations were not consistently linearly related to the total soil concentrations for each of the elements. The modelling difficulties implied by these concentration dependencies can be partially offset by including the strong negative correlation between CR and Ksub(d). The error introduced by using a mean value of the ratios for Se or U resulted in up to a ten-fold increase in variability for CR and a three-fold increase for Ksub(d). (author)

The Liquidity Coverage Ratio: the need for further complementary ratios?

OpenAIRE

Ojo, Marianne

2013-01-01

This paper considers components of the Liquidity Coverage Ratio – as well as certain prevailing gaps which may necessitate the introduction of a complementary liquidity ratio. The definitions and objectives accorded to the Liquidity Coverage Ratio (LCR) and Net Stable Funding Ratio (NSFR) highlight the focus which is accorded to time horizons for funding bank operations. A ratio which would focus on the rate of liquidity transformations and which could also serve as a complementary metric gi...

Toxicity ratios: Their use and abuse in predicting the risk from induced cancer

International Nuclear Information System (INIS)

Mays, C.W.; Taylor, G.N.; Lloyd, R.D.

1986-01-01

The toxicity ratio concept assumes the validity of certain relationships. In some examples for bone sarcoma induction, the approximate toxicity of 239 Pu in man can be calculated algebraically from the observed toxicity in the radium-dial painters and the ratio of 239 Pu/ 226 Ra toxicities in suitable laboratory mammals. In a species highly susceptible to bone sarcoma induction, the risk coefficients for both 239 Pu and 226 Ra are elevated, but the toxicity ratio of 239 Pu to 226 Ra tends to be similar to the ratio in resistant species. Among the tested species the toxicity ratio of 239 Pu to 226 Ra ranged from 6 to 22 (a fourfold range), whereas their relative sensitivities to 239 Pu varied by a factor of 150. The toxicity ratio approach can also be used to estimate the actinide risk to man from liver cancer, by comparing to the Thorotrast patients; from lung cancer, by comparing to the uranium miners and the atomic-bomb survivors; and from neutron-induced cancers, by comparing to cancers induced by gamma rays. The toxicity ratio can be used to predict the risk to man from a specific type of cancer that has been reliably induced by a reference radiation in humans and that can be induced by both the reference and the investigated radiation in suitable laboratory animals. 26 refs., 3 figs., 1 tab

Ranging Behaviour of Commercial Free-Range Laying Hens.

Science.gov (United States)

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

2016-04-26

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

Extinction Mapping and Dust-to-Gas Ratios of Nearby Galaxies using LEGUS

Science.gov (United States)

Kahre, Lauren; Walterbos, Rene; Kim, Hwihyun; Thilker, David; Lee, Janice; LEGUS Team

2018-01-01

Dust is commonly used as a tracer for cold dense gas, either through IR and NIR emission maps or through extinction mapping, and dust abundance and gas metallicity are critical constraints for chemical and galaxy evolution models. Extinction mapping has been used to trace dust column densities in the Milky Way, the Magellanic Clouds, and M31. The maps for M31 use IR and NIR photometry of red giant branch stars, which is more difficult to obtain for more distant galaxies. Work by Kahre et al. (in prep) uses the extinctions derived for individual massive stars using the isochrone-matching method described by Kim et al. (2012) to generate extinction maps for these more distant galaxies.Isochrones of massive stars lie in the same location on a color-color diagram with little dependence on metallicity and luminosity class, so the extinction can be directly derived from the observed photometry. We generate extinction maps using photometry of massive stars from the Hubble Space Telescope for several of the nearly 50 galaxies observed by the Legacy Extragalactic Ultraviolet Survey (LEGUS). The derived extinction maps will allow us to correct ground-based and HST Halpha maps for extinction, and will be used to constrain changes in the dust-to-gas ratio across the galaxy sample and in different star formation, metallicity and morphological environments. Previous studies have found links between galaxy metallicity and the dust-to-gas mass ratio. We present a study of LEGUS galaxies spanning a range of distances, metallicities, and galaxy morphologies, expanding on our previous study of metal-poor dwarfs Holmberg I and II and giant spirals NGC 6503 and NGC 628. We see clear evidence for changes in the dust-to-gas mass ratio with changing metallicity. We also examine changes in the dust-to-gas mass ratio with galactocentric radius. Ultimately, we will provide constraints on the dust-to-gas mass ratio across a wide range of galaxy environments.

Minimum short-circuit ratios for grid interconnection of wind farms with induction generators

Energy Technology Data Exchange (ETDEWEB)

Reginatto, Romeu; Rocha, Carlos [Western Parana State University (UNIOESTE), Foz do Iguacu, PR (Brazil). Center for Engineering and Exact Sciences], Emails: romeu@unioeste.br, croberto@unioeste.br

2009-07-01

This paper concerns the problem of determining the minimum value for the short-circuit ratio which is adequate for the interconnection of a given wind farms to a given grid point. First, a set of 3 criteria is defined in order to characterize the quality/safety of the interconnection: acceptable terminal voltage variations, a minimum active power margin, and an acceptable range for the internal voltage angle. Then, the minimum short circuit ratio requirement is determined for 6 different induction generator based wind turbines, both fixed-speed (with and without reactive power compensation) and variable-speed (with the following control policies: reactive power, power factor, and terminal voltage regulation). The minimum short-circuit ratio is determined and shown in graphical results for the 6 wind turbines considered, for X/R in the range 0-15, also analyzing the effect of more/less stringent tolerances for the interconnection criteria. It is observed that the tighter the tolerances the larger the minimum short-circuit ratio required. For the same tolerances in the interconnection criteria, a comparison of the minimum short circuit ratio required for the interconnection of both squirrel-cage and doubly-fed induction generators is presented, showing that the last requires much smaller values for the short-circuit ratio. (author)

Identifying Malignant Pleural Effusion by A Cancer Ratio (Serum LDH: Pleural Fluid ADA Ratio).

Science.gov (United States)

Verma, Akash; Abisheganaden, John; Light, R W

2016-02-01

We studied the diagnostic potential of serum lactate dehydrogenase (LDH) in malignant pleural effusion. Retrospective analysis of patients hospitalized with exudative pleural effusion in 2013. Serum LDH and serum LDH: pleural fluid ADA ratio was significantly higher in cancer patients presenting with exudative pleural effusion. In multivariate logistic regression analysis, pleural fluid ADA was negatively correlated 0.62 (0.45-0.85, p = 0.003) with malignancy, whereas serum LDH 1.02 (1.0-1.03, p = 0.004) and serum LDH: pleural fluid ADA ratio 0.94 (0.99-1.0, p = 0.04) was correlated positively with malignant pleural effusion. For serum LDH: pleural fluid ADA ratio, a cut-off level of >20 showed sensitivity, specificity of 0.98 (95 % CI 0.92-0.99) and 0.94 (95 % CI 0.83-0.98), respectively. The positive likelihood ratio was 32.6 (95 % CI 10.7-99.6), while the negative likelihood ratio at this cut-off was 0.03 (95 % CI 0.01-0.15). Higher serum LDH and serum LDH: pleural fluid ADA ratio in patients presenting with exudative pleural effusion can distinguish between malignant and non-malignant effusion on the first day of hospitalization. The cut-off level for serum LDH: pleural fluid ADA ratio of >20 is highly predictive of malignancy in patients with exudative pleural effusion (whether lymphocytic or neutrophilic) with high sensitivity and specificity.

Echocardiographic reference ranges for sedentary donkeys in the UK.

Science.gov (United States)

Roberts, S L; Dukes-McEwan, J

2016-10-01

The aim of this study was to provide two-dimensional (2D) and M-mode echocardiographic reference ranges from a sample of the UK population of donkeys including geriatrics (>30 years), owned by The Donkey Sanctuary, and to assess the influence of gender, weight and age on these variables. A total of 36 donkeys with no clinical or echocardiographic evidence of cardiovascular disease were examined; 24 geldings and 12 females, aged 3-45 years old, weighing 130-262 kg. Left atrial to aortic ratio was larger in geldings (P=0.004). There was no significant difference for left ventricular M-mode diastolic diameter between females and geldings (P=0.121) after exclusion of one heavy female outlier. 2D measurements significantly increased with bodyweight including maximal left atrial diameter (R(2)=0.112; P=0.046), aortic diameter at various levels (e.g. annulus: R(2)=0.35; Pdonkeys across a wide age range and shows differences compared with reference ranges from working donkeys. British Veterinary Association.

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

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

129I/127I ratios in surface waters of the English Lake District

International Nuclear Information System (INIS)

Atarashi-Andoh, M.; Schnabel, C.; Cook, G.; MacKenzie, A.B.; Dougans, A.; Ellam, R.M.; Freeman, S.; Maden, C.; Olive, V.; Synal, H.-A.; Xu, S.

2007-01-01

Accelerator Mass Spectrometry (AMS) was used to measure 129 I/ 127 I ratios in surface sea, lake, and river water samples collected in 2004 and 2005 from the English Lake District and from SW Scotland, areas which are in relatively close proximity to the Sellafield nuclear fuel reprocessing plant in NW England. The 129 I/ 127 I ratios in surface water collected from the shore of the Irish Sea were in the range 2.8 x 10 -6 to 8.2 x 10 -6 . These ratios are one order of magnitude higher than that of seawater collected from the Irish Sea in 1992, correlating with the increase in 129 I content of the Sellafield liquid effluent discharge over the last decade. The 129 I/ 127 I ratios in lakes in the Lake District were in the range 0.7 x 10 -6 to 6.4 x 10 -6 and decreased exponentially as a function of distance from Sellafield. Consideration of the relative variation of stable I concentrations and 129 I/ 127 I ratios suggests that Sellafield gaseous discharges may be the dominant source of 129 I to the lakes

Signal-to-noise ratio, contrast-to-noise ratio and their trade-offs with resolution in axial-shear strain elastography

International Nuclear Information System (INIS)

Thitaikumar, Arun; Krouskop, Thomas A; Ophir, Jonathan

2007-01-01

In axial-shear strain elastography, the local axial-shear strain resulting from the application of quasi-static axial compression to an inhomogeneous material is imaged. In this paper, we investigated the image quality of the axial-shear strain estimates in terms of the signal-to-noise ratio (SNR asse ) and contrast-to-noise ratio (CNR asse ) using simulations and experiments. Specifically, we investigated the influence of the system parameters (beamwidth, transducer element pitch and bandwidth), signal processing parameters (correlation window length and axial window shift) and mechanical parameters (Young's modulus contrast, applied axial strain) on the SNR asse and CNR asse . The results of the study show that the CNR asse (SNR asse ) is maximum for axial-shear strain values in the range of 0.005-0.03. For the inclusion/background modulus contrast range considered in this study ( asse (SNR asse ) is maximum for applied axial compressive strain values in the range of 0.005%-0.03%. This suggests that the RF data acquired during axial elastography can be used to obtain axial-shear strain elastograms, since this range is typically used in axial elastography as well. The CNR asse (SNR asse ) remains almost constant with an increase in the beamwidth while it increases as the pitch increases. As expected, the axial shift had only a weak influence on the CNR asse (SNR asse ) of the axial-shear strain estimates. We observed that the differential estimates of the axial-shear strain involve a trade-off between the CNR asse (SNR asse ) and the spatial resolution only with respect to pitch and not with respect to signal processing parameters. Simulation studies were performed to confirm such an observation. The results demonstrate a trade-off between CNR asse and the resolution with respect to pitch

Propagation effects on radio range and noise in earth-space telecommunications

Science.gov (United States)

Flock, W. L.; Slobin, S. D.; Smith, E. K.

1982-01-01

Attention is given to the propagation effects on radio range and noise in earth-space telecommunications. The use of higher frequencies minimizes ionospheric effects on propagation, but tropospheric effects often increase or dominate. For paths of geostationary satellites, and beyond, the excess range delay caused by the ionosphere and plasmasphere is proportional to the total electron content along the path and inversely proportional to frequency squared. The delay due to dry air is usually of the order of a few meters while the delay due to water vapor (a few tens of centimeters) is responsible for most of the temporal variation in the range delay for clean air. For systems such as that of the Voyager spacecraft, and for attenuation values up to about 10 dB, increased sky noise degrades the received signal-to-noise ratio more than does the reduction in signal level due to attenuation.

Why is the Ratio of Reflectivity Effective for Chlorophyll Estimation in the Lake Water?

Directory of Open Access Journals (Sweden)

Kazuo Oki

2010-07-01

Full Text Available The reasons why it is effective to estimate the chlorophyll-a concentration with the ratio of spectral radiance reflectance at the red light region and near infrared regions were shown in theory using a two-flow model. It was found that all of the backscattering coefficients can consequently be ignored by using the ratio of spectral radiance reflectance, which is the ratio of the upward radiance to the downward irradiance, at the red light and near infrared regions. In other words, the ratio can be expressed by using only absorption coefficients, which are more stable for measurement than backscattering coefficients. In addition, the band selection is crucial for producing the band ratio when the chlorophyll-a concentration is estimated without the effects of backscattering. I conclude that the two wavelengths selected must be close, but one must be within the absorption range of chlorophyll-a, and the other must be outside of the absorption range of chlorophyll-a, in order to accurately estimate the chlorophyll-a concentration.

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...

Wide-range bipolar pulse conductance instrument employing current and voltage modes with sampled or integrated signal acquisition

Energy Technology Data Exchange (ETDEWEB)

Calhoun, R K; Holler, F J [Kentucky Univ., Lexington, KY (United States). Dept. of Chemistry; Geiger, jr, R F; Nieman, T A [Illinois Univ., Urbana, IL (United States). Dept. of Chemistry; Caserta, K J [Procter and Gamble Co., Cincinnati, OH (United States)

1991-11-05

An instrument for measuring solution conductance using the bipolar pulse technique is described. The instrument is capable of measuring conductances in the range of 5x10{sup -9}-10{Omega}{sup -1} with 1% accuracy or better in as little as 32 {mu}s. Accuracy of 0.001-0.01% is achievable over the range 1x10{sup -6}-1{Omega}{sup -1}. Circuitry and software are described that allow the instrument to adjust automatically the pulse height, pulse duration, excitation mode (current or voltage pulse) and data acquisition mode (sampled or integrated) to acquire data of optimum accuracy and precision. The urease-catalyzed decomposition of urea is used to illustrate the versality of the instrument, and other applications are cited. (author). 60 refs.; 7 figs.; 2 tabs.

Medial rectus Faden operations with or without recession for partially accommodative esotropia associated with a high accommodative convergence to accommodation ratio.

Science.gov (United States)

Akar, Serpil; Gokyigit, Birsen; Sayin, Nihat; Demirok, Ahmet; Yilmaz, Omer Faruk

2013-01-01

To evaluate the results of Faden operations on the medial rectus (MR) muscles with or without recession for the treatment of partially accommodative esotropia associated with a high accommodative convergence to accommodation (AC : A) ratio and to determine whether there was a decrease in the effects of posterior fixation over time. In this retrospective study, 108 of 473 patients who underwent surgery for partially accommodative esotropia with a high AC : A ratio received Faden operations on both MR muscles, and 365 received symmetric MR muscle recessions combined with a Faden operation. For the Faden operation, a satisfactory outcome of 76.9% at 1 month postoperation, decreased to 71.3% by the final follow-up visit (mean 4.8 years). A moderate positive correlation was observed between the increase in the postoperative near deviation and postoperative time. For the Faden operations combined with MR recession, a satisfactory outcome of 78.9% at 1 month post-operation, decreased to 78.4% by the final follow-up visit. A Faden operation of the MR muscles with or without recession is an effective surgical option for treating partially accommodative esotropia associated with a high AC : A ratio. For Faden operations of the MR muscles without recession, the effects of the posterior fixation decline over time.

Practical ambiguities during calculation of energy ratios and their impacts on life cycle assessment calculations

International Nuclear Information System (INIS)

Zhang, Yongli; Colosi, Lisa M.

2013-01-01

The energy ratio metrics are increasingly important means of assessing the efficiency of energy production for emerging biofuels platforms, making comparisons among multiple alternatives, and formulating policies to foster commercialization of sustainable energy systems. However, these metrics are susceptible to inadvertent or meaningful mathematical manipulation, whereby the same dataset can be used to compute dramatically different values of energy return on investment (EROI). In this study, previously published life cycle assessment (LCA) data for algal biofuels, corn ethanol, and switchgrass ethanol are used to demonstrate how seven seemingly reasonable EROI formulations give rise to a wide range of output values. It is then demonstrated that production of bioelectricity, and to a lesser extent, other co-products, significantly increases EROI ambiguity. Overall, the EROI results are used to illustrate how EROI ambiguity makes it difficult to properly assess the energetic favorability of a particular energy system or to make accurate comparisons among multiple systems. It is then recommended that all future biofuels studies restrict themselves to usage of “EROI 1 ”, which documents all input and outputs as explicit terms, to mitigate EROI ambiguity and improve policy decision-making. - Highlights: ► Energy ratios are appealing but potentially ambiguous sustainability metrics. ► Various ratio formulations can give different metrics for the same dataset. ► Production of electricity or other co-products exacerbates ratio ambiguity

Phytate/calcium molar ratio does not predict accessibility of calcium in ready-to-eat dishes.

Science.gov (United States)

Erba, Daniela; Manini, Federica; Meroni, Erika; Casiraghi, Maria C

2017-08-01

Phytic acid (PA), a naturally occurring compound of plant food, is generally considered to affect mineral bioavailability. The aim of this study was to investigate the reliability of the PA/calcium molar ratio as a predictive factor of calcium accessibility in composed dishes and their ingredients. Dishes were chosen whose ingredients were rich in Ca (milk or cheese) or in PA (whole-wheat cereals) in order to consider a range of PA/Ca ratios (from 0 to 2.4) and measure Ca solubility using an in vitro approach. The amounts of soluble Ca in composed dishes were consistent with the sum of soluble Ca from ingredients (three out of five meals) or higher. Among whole-wheat products, bread showed higher Ca accessibility (71%, PA/Ca = 1.1) than biscuits (23%, PA/Ca = 0.9) and pasta (15%, PA/Ca = 1.5), and among Ca-rich ingredients, semi-skimmed milk displayed higher Ca accessibility (64%) than sliced cheese (50%) and Parmesan (38%). No significant correlation between the PA/Ca ratio and Ca accessibility was found (P = 0.077). The reliability of the PA/Ca ratio for predicting the availability of calcium in composed dishes is unsatisfactory; data emphasized the importance of the overall food matrix influence on mineral accessibility. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Ranging Behaviour of Commercial Free-Range Laying Hens

Directory of Open Access Journals (Sweden)

Leonard Ikenna Chielo

2016-04-01

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

Change of the mode of failure by interface friction and width-to-height ratio of coal specimens

Directory of Open Access Journals (Sweden)

Gamal Rashed

2015-06-01

Full Text Available Bumps in coal mines have been recognized as a major hazard for many years. These sudden and violent failures around mine openings have compromised safety, ventilation and access to mine workings. Previous studies showed that the violence of coal specimen failure depends on both the interface friction and width-to-height (W/H ratio of coal specimen. The mode of failure for a uniaxially loaded coal specimen or a coal pillar is a combination of both shear failure along the interface and compressive failure in the coal. The shear failure along the interface triggered the compressive failure in coal. The compressive failure of a coal specimen or a coal pillar can be controlled by changing its W/H ratio. As the W/H ratio increases, the ultimate strength increases. Hence, with a proper combination of interface friction and the W/H ratio of pillar or coal specimen, the mode of failure will change from sudden violent failure which is brittle failure to non-violent failure which is ductile failure. The main objective of this paper is to determine at what W/H ratio and interface friction the mode of failure changes from violent to non-violent. In this research, coal specimens of W/H ratio ranging from 1 to 10 were uniaxially tested under two interface frictions of 0.1 and 0.25, and the results are presented and discussed.

Management of NPA via Capital Adequacy Norms: Its effect upon the profile of Indian banks and credit deposit ratio

Directory of Open Access Journals (Sweden)

Ramesh Chandra Das

2014-01-01

Full Text Available The reform agenda in the financial as well as banking sector in the Indian economy was not only in the target of achieving profitable banking business but also to reduce the magnitude of banking funds locked in the bad debt account so that, among others, the real delivery of credit (the credit-deposit ratio rises in overall fronts. The Narasimham Committee Report in respect of reducing magnitude of non- performing assets has been framed in line with the Basel Norm regarding the asset quality of the banks where capital adequacy ratio has been fixed for different banks to achieve within different time periods. The present study, under such a back ground, has been structured to examine the profile of all Scheduled Commercial Banks in all ranges of CRAR over time in aggregate and bank group specific and to measure degree of correlation of NPA-Deposit ratio with CRAR trends and Credit-Deposit Ratio in all ranges of CRAR and their significance levels for the time period 1995-96 to 2009-2010. It has been observed that there has been variation across banks in following the guidelines of the reform committee. SBI group and foreign banks have been performing well in this respect. There has been rising trend of the proportions of banks in the above 10 per cent range of CRAR. The NPA/D ratio and C-D ratio have been observed to be positively and negatively correlated respectively for the first three ranges of CRAR and reverse in the above 10 per cent range. The correlation between the NPA/D ratio and C-D ratio is negative and significant.

Sex ratios

OpenAIRE

West, Stuart A; Reece, S E; Sheldon, Ben C

2002-01-01

Sex ratio theory attempts to explain variation at all levels (species, population, individual, brood) in the proportion of offspring that are male (the sex ratio). In many cases this work has been extremely successful, providing qualitative and even quantitative explanations of sex ratio variation. However, this is not always the situation, and one of the greatest remaining problems is explaining broad taxonomic patterns. Specifically, why do different organisms show so ...

Odds Ratio Product of Sleep EEG as a Continuous Measure of Sleep State

Science.gov (United States)

Younes, Magdy; Ostrowski, Michele; Soiferman, Marc; Younes, Henry; Younes, Mark; Raneri, Jill; Hanly, Patrick

2015-01-01

Study Objectives: To develop and validate an algorithm that provides a continuous estimate of sleep depth from the electroencephalogram (EEG). Design: Retrospective analysis of polysomnograms. Setting: Research laboratory. Participants: 114 patients who underwent clinical polysomnography in sleep centers at the University of Manitoba (n = 58) and the University of Calgary (n = 56). Interventions: None. Measurements and Results: Power spectrum of EEG was determined in 3-second epochs and divided into delta, theta, alpha-sigma, and beta frequency bands. The range of powers in each band was divided into 10 aliquots. EEG patterns were assigned a 4-digit number that reflects the relative power in the 4 frequency ranges (10,000 possible patterns). Probability of each pattern occurring in 30-s epochs staged awake was determined, resulting in a continuous probability value from 0% to 100%. This was divided by 40 (% of epochs staged awake) producing the odds ratio product (ORP), with a range of 0–2.5. In validation testing, average ORP decreased progressively as EEG progressed from wakefulness (2.19 ± 0.29) to stage N3 (0.13 ± 0.05). ORP sleep and ORP > 2.0 predicted wakefulness in > 95% of 30-s epochs. Epochs with intermediate ORP occurred in unstable sleep with a high arousal index (> 70/h) and were subject to much interrater scoring variability. There was an excellent correlation (r2 = 0.98) between ORP in current 30-s epochs and the likelihood of arousal or awakening occurring in the next 30-s epoch. Conclusions: Our results support the use of the odds ratio product (ORP) as a continuous measure of sleep depth. Citation: Younes M, Ostrowski M, Soiferman M, Younes H, Younes M, Raneri J, Hanly P. Odds ratio product of sleep EEG as a continuous measure of sleep state. SLEEP 2015;38(4):641–654. PMID:25348125

Design and simulation of a two- or four-stroke free-piston engine generator for range extender applications

International Nuclear Information System (INIS)

Jia, Boru; Smallbone, Andrew; Zuo, Zhengxing; Feng, Huihua; Roskilly, Anthony Paul

2016-01-01

Highlights: • A FPE model operated in two thermodynamic cycles is presented. • The engine performance for both gas exchange cycles are described. • Power distribution with different operation parameters are provided. • Advantages and disadvantages for the two thermodynamic cycles are summarised. - Abstract: Free-piston engines (FPEs) are known to have a greater thermal efficiency (40–50%) than an equivalent and more conventional four-stroke reciprocating engines (30–40%). Modern FPEs are proposed for the generation of electric and hydraulic power, with a potential application in hybrid electric vehicles. The numerous FPE configurations considered to date have almost exclusively operated using a two-stroke thermodynamic cycle to improve the thermal efficiency, however it is well known that the application of two-stoke cycles can be limited by noise and exhaust gas emissions constraints. In this article, a numerical model is used to investigate the techno-feasibility of operating Newcastle University’s FPE prototype using a two- or four-stroke thermodynamic cycle. If operated as a four-stroke cycle, the linear generator must be used as both a motor and a generator resulting in a more irregular piston motion compared to corresponding operating in a two-stroke cycle. In four-stroke cycles, almost half the indicated power is consumed in overcoming the pumping losses of the motoring process. Whilst the heat release process is appears to be closer to a constant volume process when operated on two-stroke engine cycle, the peak cylinder pressure and compression ratio proved lower. In addition, a narrower power range is reported for a four-stroke cycle despite a corresponding higher thermal efficiency.

Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy

Science.gov (United States)

Wang, Yaqiang; Wang, Ruiwu; Li, Yaotang; (Sam) Ma, Zhanshan

2016-12-01

There are three sex ratio strategies (SRS) in nature—male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton’s local mate competition (LMC) and Clark’s local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC & LRC) in the field of SRS research.

Calibration and assessment of channel-specific biases in microarray data with extended dynamical range.

Science.gov (United States)

Bengtsson, Henrik; Jönsson, Göran; Vallon-Christersson, Johan

2004-11-12

Non-linearities in observed log-ratios of gene expressions, also known as intensity dependent log-ratios, can often be accounted for by global biases in the two channels being compared. Any step in a microarray process may introduce such offsets and in this article we study the biases introduced by the microarray scanner and the image analysis software. By scanning the same spotted oligonucleotide microarray at different photomultiplier tube (PMT) gains, we have identified a channel-specific bias present in two-channel microarray data. For the scanners analyzed it was in the range of 15-25 (out of 65,535). The observed bias was very stable between subsequent scans of the same array although the PMT gain was greatly adjusted. This indicates that the bias does not originate from a step preceding the scanner detector parts. The bias varies slightly between arrays. When comparing estimates based on data from the same array, but from different scanners, we have found that different scanners introduce different amounts of bias. So do various image analysis methods. We propose a scanning protocol and a constrained affine model that allows us to identify and estimate the bias in each channel. Backward transformation removes the bias and brings the channels to the same scale. The result is that systematic effects such as intensity dependent log-ratios are removed, but also that signal densities become much more similar. The average scan, which has a larger dynamical range and greater signal-to-noise ratio than individual scans, can then be obtained. The study shows that microarray scanners may introduce a significant bias in each channel. Such biases have to be calibrated for, otherwise systematic effects such as intensity dependent log-ratios will be observed. The proposed scanning protocol and calibration method is simple to use and is useful for evaluating scanner biases or for obtaining calibrated measurements with extended dynamical range and better precision. The

The Contribution of Matched Envelope Dynamic Range to the Binaural Benefits in Simulated Bilateral Electric Hearing

Science.gov (United States)

Chen, Fei; Wong, Lena L. N.; Qiu, Jianxin; Liu, Yehai; Azimi, Behnam; Hu, Yi

2013-01-01

Purpose: This study examined the effects of envelope dynamic-range mismatch on the intelligibility of Mandarin speech in noise by simulated bilateral electric hearing. Method: Noise-vocoded Mandarin speech, corrupted by speech-shaped noise at 5 and 0 dB signal-to-noise ratios, was presented unilaterally or bilaterally to 10 normal-hearing…

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.

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?

Origin of Manipur Ophiolite Complex, Indo-Myanmar Range ...

Indian Academy of Sciences (India)

r b

2017-11-20

Nov 20, 2017 ... The Manipur. Ophiolite. Complex: Varying degree of serpentinization and relict pyroxenes. 11/20/2017. 13. Page 14. Serpentinization process preserves the protolith elemental signatures. 11/20/2017. 14 ... The range of Nd isotope ratios in the serpentinized peridotites. 11/20/2017. 17. Kingson et al.

Effect of the addition of nitrogen sources to cassava fiber and carbon-to-nitrogen ratios on Agaricus brasiliensis growth.

Science.gov (United States)

Mantovani, T R D; Linde, G A; Colauto, N B

2007-01-01

The same substratum formulation to grow Agaricus bisporus has been used to grow Agaricus brasiliensis since its culture started in Brazil. Despite being different species, many of the same rules have been used for composting or axenic cultivation when it comes to nitrogen content and source in the substrate. The aim of this study was to verify the mycelial growth of A. brasiliensis in different ammonium sulfate and (or) urea concentrations added to cassava fiber and different carbon-to-nitrogen (C:N) ratios to increase the efficiency of axenic cultivation. Two nitrogen sources (urea and (or) ammonium sulfate) added to cassava fiber were tested for the in vitro mycelial growth in different C:N ratios (ranging from 2.5:l to 50:l) in the dark at 28 degrees C. The radial mycelial growth was measured after 8 days of growth and recorded photographically at the end of the experiment. Nitrogen from urea enhanced fungal growth better than ammonium sulfate or any mixture of nitrogen. The best C:N ratios for fungal growth were from 10:l to 50:l; C:N ratios below 10:l inhibited fungal growth.

Reproducibility of isotope ratio measurements

International Nuclear Information System (INIS)

Elmore, D.

1981-01-01

The use of an accelerator as part of a mass spectrometer has improved the sensitivity for measuring low levels of long-lived radionuclides by several orders of magnitude. However, the complexity of a large tandem accelerator and beam transport system has made it difficult to match the precision of low energy mass spectrometry. Although uncertainties for accelerator measured isotope ratios as low as 1% have been obtained under favorable conditions, most errors quoted in the literature for natural samples are in the 5 to 20% range. These errors are dominated by statistics and generally the reproducibility is unknown since the samples are only measured once

Measurement of the atmospheric muon charge ratio with the OPERA detector

OpenAIRE

Mauri, Nicoletta

2011-01-01

The atmospheric muon charge ratio, defined as the number of positive over negative charged muons, is an interesting quantity for the study of high energy hadronic interactions in atmosphere and the nature of the primary cosmic rays. The measurement of the charge ratio in the TeV muon energy range allows to study the hadronic interactions in kinematic regions not yet explored at accelerators. The OPERA experiment is a hybrid electronic detector/emulsion apparatus, located in the undergroun...

The prognostic value of lymph node ratio in a national cohort of rectal cancer patients

DEFF Research Database (Denmark)

Lykke, J; Jess, P; Roikjaer, O

2016-01-01

OBJECTIVE: To analyze the prognostic implications of the lymph node ratio (LNR) in curative resected rectal cancer. SUMMARY BACKGROUND DATA: It has been proposed that the LNR has a high prognostic impact in colorectal cancer, but the lymph node ratio has not been evaluated exclusively for rectal......-adjuvant treatment had been given. RESULTS: In a multivariate analysis the pN status, ypN status and lymph node yield were found to be independent prognostic factors for overall survival, irrespective of neo-adjuvant therapy. The LNR was also found to be a significant prognostic factor with a Hazard Ratio ranging...... cancer in a large national cohort study. METHODS: All 6793 patients in Denmark diagnosed with stage I to III adenocarcinoma of the rectum, and so treated in the period from 2003 to 2011, were included in the analysis. The cohort was divided into two groups according to whether or not neo...

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.

Gauge hierarchy and long range forces

International Nuclear Information System (INIS)

Pal, P.B.; Keung, Wai-Yee; Chang, D.

1990-01-01

With the aid of simple examples, we show how a long range attractive force can arise in a gauge theory with a hierarchy. The force is due to the exchange of a Higgs boson whose mass and matter couplings are both naturally suppressed by the hierarchical mass ratio. Such bosons appear if there is an accidental global symmetry in the low-energy renormalizable Lagrangian after the high energy symmetry breaking. 6 refs

Long-range correlations from colour confinement

International Nuclear Information System (INIS)

Jurkiewicz, J.; Zenczykowski, P.

1979-01-01

A class of independent parton emission models is generalized by the introduction of the colour degrees of freedom. In the proposed models colour confinement extorts strong long-range forward-backward correlations, the rise of one-particle inclusive distribution and the KNO scaling. It leads to the analytically calculable definite asymptotic predictions for the D/ ratio which depends only on the choice of the colour group. Multiplicity distribution develops a remarkably long tail. (author)

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…

Simulation of channelled ion ranges in crystalline silicon

International Nuclear Information System (INIS)

Kabadayi, Oender; Guemues, Hasan

2004-01-01

We present results from a channelled ion range simulation model based on separation of ion trajectories into three different categories known as random, channelled, and well-channelled. We present this for boron projectiles incident along the Si direction. Stopping powers for channelled particles, well-channelled, and random particles are determined using experimental ratios of random and channelled stopping powers for a boron/silicon system. We have found the particle range distributions and the mean range of particles in crystalline channels. A new program code has been developed for the implementation of the presented model. The results are compared with experimental data as well as Crystal-transport and range of ions in matter, stopping and ranges of ions in matter, and projected range algorithm programs. We have found good agreement between our calculations and experiment, with an average discrepancy of 7%. Our model is also able to simulate the observed shift towards larger depths for the main ion distribution under channelling conditions

Ventilation and ventilation/perfusion ratios

International Nuclear Information System (INIS)

Valind, S.O.

1989-01-01

The thesis is based on five different papers. The labelling of specific tracer compounds with positron emitting radionuclides enables a range of structural, physiological and biochemical parameters in the lung to be measured non-invasively, using positron emission tomography. This concept affords a unique opportunity for in vivo studies of different expressions of pulmonary pathophysiology at the regional level. The present thesis describes the application of positron emission tomography to the measurements of ventilation and ventilation/perfusion ratios using inert gas tracers, neon-19 and nitrogen-13 respectively. The validity of the methods applied was investigated with respect to the transport of inert gas tracers in the human lung. Both ventilation and the ventilation/perfusion ratio may be obtained with errors less than 10 % in the normal lung. In disease, however, errors may increase in those instances where the regional ventilation is very low or the intra-regional gas flow distribution is markedly nonuniform. A 2-3 fold increase in ventilation was demonstrated in normal nonsmoking subjects going from ventral to dorsal regions in the supine posture. These large regional differences could be well explained by the intrinsic elastic properties of lung tissue, considering the gravitational gradient in transpulmonary pressure. In asymptomatic smokers substantial regional ventilatroy abnormalities were found whilst the regional gas volume was similar in smokers and nonsmokers. The uncoupling between ventilation and gas volume probably reflects inflammatory changes in the airways. The regional differences in dV/dt/dQ/dt were relatively small and blood flow was largely matched to ventilation in the supine posture. However, small regions of lung with very low ventilation, unmatched by blood flow commonly exists in the most dependent parts of the lung in both smokers and nonsmokers. (29 illustrations, 7 tables, 113 references)

Sensitivity and Dynamic Range Considerations for Homodyne Detection Systems

DEFF Research Database (Denmark)

Jaggard, Dwight L.; King, Ray J

1973-01-01

The effects of modulation frequency, RF reference power, and external bias upon the sensitivity and dynamic range of microwave homodyne detection systems was measured for point contact diodes and low l/f noise Schottky and backward diodes. The measurements were made at 4.89 GHz using a signal...... to noise ratio of 3 dB and a detection system bandwidth of 10 Hz. Maximum sensitivities of -135, -150, and -145 dBm, and dynamic ranges of 92, 110, and 124 dB were measured for the point contact, Schottky, and backward diodes at modulation frequencies of 30, 30, and 3 kHz, respectively. It was found...... that the level of RF reference signal needed to obtain the maximum sensitivity was equal to or somewhat above the point where the diode changes from square law to linear detection. The results are significant in that previously reported homodyne sensitivities (not necessarily maximum) were on the order of -90...

Monte Carlo simulation of the effect of miniphantom on in-air output ratio

International Nuclear Information System (INIS)

Li Jun; Zhu, Timothy C.

2010-01-01

Purpose: The aim of the study was to quantify the effect of miniphantoms on in-air output ratio measurements, i.e., to determine correction factors for in-air output ratio. Methods: Monte Carlo (MC) simulations were performed to simulate in-air output ratio measurements by using miniphantoms made of various materials (PMMA, graphite, copper, brass, and lead) and with different longitudinal thicknesses or depths (2-30 g/cm 2 ) in photon beams of 6 and 15 MV, respectively, and with collimator settings ranging from 3x3 to 40x40 cm 2 . EGSnrc and BEAMnrc (2007) software packages were used. Photon energy spectra corresponding to the collimator settings were obtained from BEAMnrc code simulations on a linear accelerator and were used to quantify the components of in-air output ratio correction factors, i.e., attenuation, mass energy absorption, and phantom scatter correction factors. In-air output ratio correction factors as functions of miniphantom material, miniphantom longitudinal thickness, and collimator setting were calculated and compared to a previous experimental study. Results: The in-air output ratio correction factors increase with collimator opening and miniphantom longitudinal thickness for all the materials and for both energies. At small longitudinal thicknesses, the in-air output ratio correction factors for PMMA and graphite are close to 1. The maximum magnitudes of the in-air output ratio correction factors occur at the largest collimator setting (40x40 cm 2 ) and the largest miniphantom longitudinal thickness (30 g/cm 2 ): 1.008±0.001 for 6 MV and 1.012±0.001 for 15 MV, respectively. The MC simulations of the in-air output ratio correction factor confirm the previous experimental study. Conclusions: The study has verified that a correction factor for in-air output ratio can be obtained as a product of attenuation correction factor, mass energy absorption correction factor, and phantom scatter correction factor. The correction factors obtained in the

PENGARUH PERUBAHAN RETURN ON ASSETS, PERUBAHAN DEBT TO EQUITY RATIO DAN PERUBAHAN CASH RATIO TERHADAP PERUBAHAN DIVIDEND PAYOUT RATIO

Directory of Open Access Journals (Sweden)

Yuli Soesetio

2008-02-01

Full Text Available Dividend Payout Ratio used to calculate all of revenue that will be accepted by stockholders as cash dividend, usually explained as percentage. This research was conducted to know several factors that affected change of Dividend Payout Ratio and to know the significance level and the correlation between dependent and independent variable. Analysis instrument used was parametric statistic. Based on the result of statistic test,  The Change of Return on Asset (X1, The Change of Debt to Equity Ratio (X2,  were able to explain dependent variable of the change Dividend Payout Ratio, and The Change of CashRatio can’t explain dependent variable of the change Dividend Payout Ratio

Adult sex ratios and their implications for cooperative breeding in birds.

Science.gov (United States)

Komdeur, Jan; Székely, Tamás; Long, Xiaoyan; Kingma, Sjouke A

2017-09-19

Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations in adult sex ratio (ASR, the proportion of males in the adult population) have been hypothesized to influence the occurrence of cooperative breeding because of the resulting surplus of one sex and limited availability of breeding partners, this hypothesis has not been tested across a wide range of taxa. By using data from 188 bird species and phylogenetically controlled analyses, we show that cooperatively breeding species have more male-biased ASRs than non-cooperative species. Importantly, ASR predicts helper sex ratio: in species with more male-biased ASR, helper sex ratio is also more male biased. We also show that offspring sex ratios do not predict ASRs, so that the skewed ASRs emerge during the period when individuals aim to obtain a breeding position or later during adulthood. In line with this result, we found that ASR (among both cooperatively and non-cooperatively breeding species) is inversely related to sex bias in dispersal distance, suggesting that the cost of dispersal is more severe for the further-dispersing sex. As females usually disperse further in birds, this explains the generally male-biased ASR, and in combination with benefits of philopatry for males, this probably explains why ASR is more biased in cooperatively breeding species. Taken together, our results suggest that a sex bias in helping in cooperatively breeding species relates to biased ASRs. We propose that this relationship is driven by sex-specific costs and benefits of dispersal and helping, as well as other demographic factors. Future phylogenetic comparative and experimental work is needed to establish how this relationship emerges.This article is part of the themed issue 'Adult sex

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.

A Short-Range Distance Sensor with Exceptional Linearity

Science.gov (United States)

Simmons, Steven; Youngquist, Robert

2013-01-01

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

High Precision Ranging and Range-Rate Measurements over Free-Space-Laser Communication Link

Science.gov (United States)

Yang, Guangning; Lu, Wei; Krainak, Michael; Sun, Xiaoli

2016-01-01

We present a high-precision ranging and range-rate measurement system via an optical-ranging or combined ranging-communication link. A complete bench-top optical communication system was built. It included a ground terminal and a space terminal. Ranging and range rate tests were conducted in two configurations. In the communication configuration with 622 data rate, we achieved a two-way range-rate error of 2 microns/s, or a modified Allan deviation of 9 x 10 (exp -15) with 10 second averaging time. Ranging and range-rate as a function of Bit Error Rate of the communication link is reported. They are not sensitive to the link error rate. In the single-frequency amplitude modulation mode, we report a two-way range rate error of 0.8 microns/s, or a modified Allan deviation of 2.6 x 10 (exp -15) with 10 second averaging time. We identified the major noise sources in the current system as the transmitter modulation injected noise and receiver electronics generated noise. A new improved system will be constructed to further improve the system performance for both operating modes.

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 ratio DT/μ for electrons in water vapour at 294 K

International Nuclear Information System (INIS)

Elford, M.T.

1995-01-01

The ratio D T /μ for electrons in water vapour (294 K) has been measured by the Townsend-Huxley method as a function of E/N (where E is the electric field strength and N the gas number density) at vapour pressures ranging from 0.103 to 0.413 kPa. For E/N ≤ 30 Td, where attachment and ionisation may be neglected, the values are found to be independent of vapour pressure and of the current ratio relation used to derive D T /μ values from the measured current ratios. The uncertainty of these D T /μ values is estimated to be T /μ measured at E/N > 30 Td were found to be strongly pressure dependent, the strength and sign of the dependence depending on E/N and the current ratio relation used. Since extrapolation to infinite pressure at each E/N value did not give the same value of D T /μ, it has not been possible to derive reliable D T /μ values for this higher E/N range. Possible causes of the observed pressure dependences are discussed. The present data are in good agreement with the values predicted by Ness and Robson for values of E/N ≤ 24 Td. 17 refs., 1 tab., 5 figs

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.

Tokamak reactor designs as a function of aspect ratio

International Nuclear Information System (INIS)

Wong, C.P.C.; Stambaugh, R.D.

2000-01-01

This paper assesses the technical and economic potential of tokamak power plants which utilize superconducting coil (SC) or normal conducting coil (NC) designs as a function of aspect ratio (A). Based on the results from plasma equilibrium calculations, the key physics design parameters of β N , β p , β T , and κ were fitted to parametric equations covering A in the range of 1.2-6. By using ARIES-RS and ARIES-ST as reference design points, a fusion reactor system code was used to project the performance and cost of electricity (COE) of SC and NC reactor designs over the same range of A. The principle difference between the SC and the NC designs are the inboard standoff distance between the coil and the inboard first wall, and the maximum central column current density used for respective coil types. Results show that at an output power of 2 GWe both NC and SC designs can project COE in the respectable range of 62-65 mill/kW h at gross thermal efficiency of 46%, with neutron wall loading (Γ n ) ∼7 MW/m 2 . More importantly, we have learned that based on the present knowledge of equilibrium physics and fusion power core components and system design we can project the performance and COE of reactor designs at least for the purpose of comparative assessment. Tokamak design points can then be selected and optimized for testing or commercial devices as a function of output power, A and Γ n for both SC and NC design options

Consumer acceptance of eggs from Hy-Line Brown layers fed soybean or soybean-free diets using cage or free-range rearing systems.

Science.gov (United States)

Al-Ajeeli, M N; Miller, R K; Leyva, H; Hashim, M M; Abdaljaleel, R A; Jameel, Y; Bailey, C A

2018-05-01

Consumers have begun to awaken to the food on their plates with respect to human health and the environment, as well as animal welfare. They have become more demanding about what they buy or prefer in their food, such as soy-free, gluten-free, or organic products. The objective of this study was to evaluate consumer acceptance of eggs from hens fed soybean meal or soybean-free diets utilizing cottonseed meal and distillers' dried grains, using cage or free-range rearing systems. All eggs were stored at the sensory lab at Texas A&M University (TAMU) for a d prior to each test at 4°C. A panel of consumers (n = 60) made up of TAMU students, faculty, and staff, ages 18 to 50, were recruited to evaluate consumer acceptance based on 2 tests using scrambled and hard cooked eggs. Samples were placed in separate weigh boats labeled with 3-digit codes to avoid visual bias. Sensory ballots were based on overall like or dislike of flavor, texture, odor, and color using the 9-point hedonic scales. For scrambled eggs, flavor did not differ (P > 0.05), but texture liking was higher (P = 0.064) for scrambled eggs from the soybean-free diet (7.08) vs. scrambled eggs from the soybean meal diet (6.65). With respect to the hard cooked eggs, the consumer panel preferred the flavor of the eggs from the caged rearing system (7.11) vs. eggs from the free-range system (6.60; P = 0.014). Consumers liked the texture (P = 0.018) for eggs collected from hens fed soybean meal (6.91) vs. eggs from hens fed the soybean-free diet (6.30).

Prognostic value of the serum free light chain ratio in newly diagnosed myeloma: proposed incorporation into the international staging system.

Science.gov (United States)

Snozek, C L H; Katzmann, J A; Kyle, R A; Dispenzieri, A; Larson, D R; Therneau, T M; Melton, L J; Kumar, S; Greipp, P R; Clark, R J; Rajkumar, S V

2008-10-01

To determine if the serum free light chain (FLC) ratio has prognostic value in patients with symptomatic multiple myeloma (MM), baseline serum samples from a well-characterized cohort of 790 newly diagnosed MM patients were tested with the FLC assay. FLC ratio was calculated as kappa/lambda (reference range 0.26-1.65). On the basis of the distribution of values, a cutpoint kappa/lambda FLC ratio of 32 was chosen for further analysis. Overall survival was significantly inferior in patients with an abnormal FLC ratio of 32 (n=479) compared with those with an FLC ratio between 0.03 and 32 (n=311), with median survival of 30 versus 39 months, respectively. We incorporated abnormal FLC ratio with the International Staging System (ISS) risk factors (that is, albumin or=3.5 g/l), to create a risk stratification model with improved prognostic capabilities. Patients with 0, 1, 2 or 3 adverse risk factors had significantly different overall survival, with median survival times of 51, 39, 30 and 22 months, respectively (P<0.001). These findings suggest that the serum FLC ratio at initial diagnosis is an important predictor of prognosis in myeloma, and can be incorporated into the ISS for improved risk stratification.

Maternal condition but not corticosterone is linked to offspring sex ratio in a passerine bird.

Directory of Open Access Journals (Sweden)

Lindsay J Henderson

Full Text Available There is evidence of offspring sex ratio adjustment in a range of species, but the potential mechanisms remain largely unknown. Elevated maternal corticosterone (CORT is associated with factors that can favour brood sex ratio adjustment, such as reduced maternal condition, food availability and partner attractiveness. Therefore, the steroid hormone has been suggested to play a key role in sex ratio manipulation. However, despite correlative and causal evidence CORT is linked to sex ratio manipulation in some avian species, the timing of adjustment varies between studies. Consequently, whether CORT is consistently involved in sex-ratio adjustment, and how the hormone acts as a mechanism for this adjustment remains unclear. Here we measured maternal baseline CORT and body condition in free-living blue tits (Cyanistes caeruleus over three years and related these factors to brood sex ratio and nestling quality. In addition, a non-invasive technique was employed to experimentally elevate maternal CORT during egg laying, and its effects upon sex ratio and nestling quality were measured. We found that maternal CORT was not correlated with brood sex ratio, but mothers with elevated CORT fledged lighter offspring. Also, experimental elevation of maternal CORT did not influence brood sex ratio or nestling quality. In one year, mothers in superior body condition produced male biased broods, and maternal condition was positively correlated with both nestling mass and growth rate in all years. Unlike previous studies maternal condition was not correlated with maternal CORT. This study provides evidence that maternal condition is linked to brood sex ratio manipulation in blue tits. However, maternal baseline CORT may not be the mechanistic link between the maternal condition and sex ratio adjustment. Overall, this study serves to highlight the complexity of sex ratio adjustment in birds and the difficulties associated with identifying sex biasing mechanisms.

Novel Apparatus for the Real-Time Quantification of Dissolved Gas Concentrations and Isotope Ratios

Science.gov (United States)

Gupta, M.; Leen, J.; Baer, D. S.; Owano, T. G.; Liem, J.

2013-12-01

Measurements of dissolved gases and their isotopic composition are critical in studying a variety of phenomena, including underwater greenhouse gas generation, air-surface exchange, and pollution migration. These studies typically involve obtaining water samples from streams, lakes, or ocean water and transporting them to a laboratory, where they are degased. The gases obtained are then generally measured using gas chromatography and isotope ratio mass spectrometry for concentrations and isotope ratios, respectively. This conventional, off-line methodology is time consuming, significantly limits the number of the samples that can be measured and thus severely inhibits detailed spatial and temporal mapping of gas concentrations and isotope ratios. In this work, we describe the development of a new membrane-based degassing device that interfaces directly to Los Gatos Research (cavity enhanced laser absorption or Off-Axis ICOS) gas analyzers (cavity enhanced laser absorption or Off-Axis ICOS analyzers) to create an autonomous system that can continuously and quickly measure concentrations and isotope ratios of dissolved gases in real time in the field. By accurately controlling the water flow rate through the membrane degasser, gas pressure on the outside of the membrane, and water pressure on the inside of the membrane, the system is able to generate precise and highly reproducible results. Moreover, by accurately measuring the gas flow rates in and out of the degasser, the gas-phase concentrations (ppm) could be converted into dissolved gas concentrations (nM). We will present detailed laboratory test data that quantifies the linearity, precision, and dynamic range of the system for the concentrations and isotope ratios of dissolved methane, carbon dioxide, and nitrous oxide. By interfacing the degassing device to a novel cavity-enhanced spectrometer (developed by LGR), preliminary data will also be presented for dissolved volatile organics (VOC) and other

Theory of mass-discrimination effects in ion extraction from a plasma of wide pressure range

International Nuclear Information System (INIS)

Chang, J.-S.; Kodera, K.

1979-01-01

Mass-discrimination effects in stagnation-point ion extraction are treated for a plasma with a wide range of Knudsen number, i.e. when the charged particle's mean free path 3 , ion Schmidt numbers, from 0 to 10 4 , the effective Knudsen number K from 0 to infinity, and the Debye ratio Rsub(p)/lambdasub(D) from 0 to 10 -1 . Numerical results show that: (1) for a non-flowing plasma, mass-discrimination effects increase with increasing effective Knudsen number (or gas pressure) and decreasing sampling potential; (2) for a non-flowing plasma, no significant effect of the Debye ratio on mass-discrimination was found; (3) for a flowing plasma, mass-discrimination effects decrease with increasing Reynolds number (or flow velocity) and ion Schmidt number, and with decreasing sampling potential and effective Knudsen number. (Auth.)

Detection of counterfeit antiviral drug Heptodin and classification of counterfeits using isotope amount ratio measurements by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) and isotope ratio mass spectrometry (IRMS).

Science.gov (United States)

Santamaria-Fernandez, Rebeca; Hearn, Ruth; Wolff, Jean-Claude

2009-06-01

Isotope ratio mass spectrometry (IRMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) are highly important techniques that can provide forensic evidence that otherwise would not be available. MC-ICP-MS has proved to be a very powerful tool for measuring high precision and accuracy isotope amount ratios. In this work, the potential of combining isotope amount ratio measurements performed by MC-ICP-MS and IRMS for the detection of counterfeit pharmaceutical tablets has been investigated. An extensive study for the antiviral drug Heptodin has been performed for several isotopic ratios combining MC-ICP-MS and an elemental analyser EA-IRMS for stable isotope amount ratio measurements. The study has been carried out for 139 batches of the antiviral drug and analyses have been performed for C, S, N and Mg isotope ratios. Authenticity ranges have been obtained for each isotopic system and combined to generate a unique multi-isotopic pattern only present in the genuine tablets. Counterfeit tablets have then been identified as those tablets with an isotopic fingerprint outside the genuine isotopic range. The combination of those two techniques has therefore great potential for pharmaceutical counterfeit detection. A much greater power of discrimination is obtained when at least three isotopic systems are combined. The data from these studies could be presented as evidence in court and therefore methods need to be validated to support their credibility. It is also crucial to be able to produce uncertainty values associated to the isotope amount ratio measurements so that significant differences can be identified and the genuineness of a sample can be assessed.

Multilayered samples reconstructed by measuring K{sub α}/K{sub β} or L{sub α}/L{sub β} X-ray intensity ratios by EDXRF

Energy Technology Data Exchange (ETDEWEB)

Cesareo, Roberto, E-mail: cesareo@uniss.it [Istituto per lo Studio dei Materiali Nano Strutturati, CNR-Montelibretti, via Salaria km. 29.5, 00015 Monterotondo (Romania); Assis, Joaquim T. de, E-mail: joaquim.iprj@gmail.com [Universidade do Estado do Rio de Janeiro, Instituto Politécnico, P.O. Box 97282, 28625-570 Nova Friburgo, RJ (Brazil); Roldán, Clodoaldo, E-mail: Clodoaldo.Roldan@uv.es [Instituto de Ciencia de los Materiales, Universidad de Valencia, P.O. Box 22085, E46071 Valencia (Spain); Bustamante, Angel D., E-mail: angelbd1@gmail.com [Universidad Nacional Mayor de San Marcos, Lima (Peru); Brunetti, Antonio, E-mail: brunetti@uniss.it [Dipartimento di Scienze Politiche, Scienza della Comunicazione e Ingegneria dell’ Informazione, Università di Sassari, Sassari (Italy); Schiavon, Nick [Hercules Laboratory and Évora Geophysical Centre, University of Evora (Portugal)

2013-10-01

In this paper a general method based on energy-dispersive X-ray fluorescence (EDXRF) analysis has been tested to assess its possible use as a tool to reconstruct the structure and determine the thickness of two and/or multi-layered materials. The method utilizes the X-ray intensity ratios of K{sub α}/K{sub β} or L{sub α}/L{sub β} peaks (or the ratio of these peaks) for selected elements present in multi-layered objects of various materials (Au alloys, gilded Cu, gilded Ag, gilded Pb, Ag–Au Tumbaga, stone surfaces with protective treatments, Zn or Nickel plating on metals). Results show that, in the case of multi-layered samples, a correct calculation of the peak ratio (K{sub α} /K{sub β} and/or L{sub α}/L{sub β}) of relevant elements from energy-dispersive X-ray fluorescence spectra, can provide important information in assessing the exact location of each layer and for calculating its thickness. The methodological approach shown may have important applications not only in materials science but also when dealing with the conservation and restoration of multi-layered cultural heritage objects where the use of a Non-Destructive techniques to determine slight chemical and thickness variations in the layered structure is often of paramount importance to achieve the best results.

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

Isotope yield ratios as a probe of the reaction dynamics

International Nuclear Information System (INIS)

Trautmann, W.; Hildenbrand, K.D.; Lynen, U.; Mueller, W.F.J.; Rabe, H.J.; Sann, H.; Stelzer, H.; Trockel, R.; Wada, R.; Brummund, N.; Glasow, R.; Kampert, K.H.; Santo, R.; Eckert, E.M.; Pochodzalla, J.; Bock, I.; Pelte, D.

1987-04-01

Isotopically resolved yields of particles and complex fragments from 12 C and 18 O induced reactions on 53 Ni, 54 Ni, Ag, and 197 Au in the intermediate range of bombarding energies 30 MeV ≤ E/A ≤ 84 MeV were measured. The systematic variation of the deduced isotope yield ratios with projectile and target is used to determine the degree of N/Z equilibration achieved and to establish time scales for the reaction process. A quantum statistical model is employed in order to derive entropies of the emitting systems from the measured isotope yield ratios. (orig.)

Bi-Directional Brillouin Optical Time Domain Analyzer System for Long Range Distributed Sensing

Science.gov (United States)

Guo, Nan; Wang, Liang; Wang, Jie; Jin, Chao; Tam, Hwa-Yaw; Zhang, A. Ping; Lu, Chao

2016-01-01

We propose and experimentally demonstrate a novel scheme of bi-directional Brillouin time domain analyzer (BD-BOTDA) to extend the sensing range. By deploying two pump-probe pairs at two different wavelengths, the Brillouin frequency shift (BFS) distribution over each half of the whole fiber can be obtained with the simultaneous detection of Brillouin signals in both channels. Compared to the conventional unidirectional BOTDA system of the same sensing range, the proposed BD-BOTDA scheme enables distributed sensing with a performance level comparable to the conventional one with half of the sensing range and a spatial resolution of 2 m, while maintaining the Brillouin signal-to-noise ratio (SNR) and the BFS uncertainty. Based on this technique, we have achieved distributed temperature sensing with a measurement range of 81.9 km fiber at a spatial resolution of 2 m and BFS uncertainty of ~0.44 MHz without introducing any complicated components or schemes. PMID:27999250

Bi-Directional Brillouin Optical Time Domain Analyzer System for Long Range Distributed Sensing.

Science.gov (United States)

Guo, Nan; Wang, Liang; Wang, Jie; Jin, Chao; Tam, Hwa-Yaw; Zhang, A Ping; Lu, Chao

2016-12-16

We propose and experimentally demonstrate a novel scheme of bi-directional Brillouin time domain analyzer (BD-BOTDA) to extend the sensing range. By deploying two pump-probe pairs at two different wavelengths, the Brillouin frequency shift (BFS) distribution over each half of the whole fiber can be obtained with the simultaneous detection of Brillouin signals in both channels. Compared to the conventional unidirectional BOTDA system of the same sensing range, the proposed BD-BOTDA scheme enables distributed sensing with a performance level comparable to the conventional one with half of the sensing range and a spatial resolution of 2 m, while maintaining the Brillouin signal-to-noise ratio (SNR) and the BFS uncertainty. Based on this technique, we have achieved distributed temperature sensing with a measurement range of 81.9 km fiber at a spatial resolution of 2 m and BFS uncertainty of ~0.44 MHz without introducing any complicated components or schemes.

Flow Range of Centrifugal Compressor Being Extended

Science.gov (United States)

Skoch, Gary J.

2001-01-01

General Aviation will benefit from turbine engines that are both fuel-efficient and reliable. Current engines fall short of their potential to achieve these attributes. The reason is compressor surge, which is a flow stability problem that develops when the compressor is subjected to conditions that are outside of its operating range. Compressor surge can occur when fuel flow to the engine is increased, temporarily back pressuring the compressor and pushing it past its stability limit, or when the compressor is subjected to inlet flow-field distortions that may occur during takeoff and landing. Compressor surge can result in the loss of an aircraft. As a result, engine designers include a margin of safety between the operating line of the engine and the stability limit line of the compressor. Unfortunately, the most efficient operating line for the compressor is usually closer to its stability limit line than it is to the line that provides an adequate margin of safety. A wider stable flow range will permit operation along the most efficient operating line of the compressor, improving the specific fuel consumption of the engine and reducing emissions. The NASA Glenn Research Center is working to extend the stable flow range of the compressor. Significant extension has been achieved in axial compressors by injecting air upstream of the compressor blade rows. Recently, the technique was successfully applied to a 4:1 pressure ratio centrifugal compressor by injecting streams of air into the diffuser. Both steady and controlled unsteady injection were used to inject air through the diffuser shroud surface and extend the range. Future work will evaluate the effect of air injection through the diffuser hub surface and diffuser vanes with the goal of maximizing the range extension while minimizing the amount of injected air that is required.

Tracing the origin of pollution in French Alpine snow and aerosols using lead isotopic ratios.

Science.gov (United States)

Veysseyre, A M; Bollhöfer, A F; Rosman, K J; Ferrari, C P; Boutron, C F

2001-11-15

Fresh snow samples collected at 15 remote locations and aerosols collected at one location in the French Alps between November 1998 and April 1999 have been analyzed for Pb concentration and isotopic composition by thermal ionization mass spectrometry. The snow samples contained 19-1300 pg/g of Pb with isotopic ratios 206Pb/207Pb (208Pb/207Pb) of 1.1279-1.1607 (2.3983-2.4302). Airborne Pb concentrations at one sampling site ranged from 0.42 to 6.0 ng/m3 with isotopic ratios of 1.1321-1.1427 (2.4029-2.4160). Air mass trajectory analysis combined with isotopic compositions of potential source regions did not show discernible evidence of the long-range atmospheric transport of pollutants. Isotopic ratios in the Alpine snow samples and thus the free troposphere were generally higher than airborne Pb isotopic ratios in urban France, which coupled with the relatively high Pb concentrations suggested a regional anthropogenic Pb source, probably Italy but possibly Eastern Europe.

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

Pretreatment Neutrophil-Lymphocyte Ratio as a Predictor in Bladder Cancer and Metastatic or Unresectable Urothelial Carcinoma Patients: a Pooled Analysis of Comparative Studies.

Science.gov (United States)

Wu, Shuiqing; Zhao, Xiaokun; Wang, Yinhuai; Zhong, Zhaohui; Zhang, Lei; Cao, Jian; Ai, Kai; Xu, Ran

2018-01-01

Emerging studies have shown that the neutrophil-lymphocyte ratio (NLR) is a potential predictor in various tumors. Our study was conducted to assess the prognostic value of the pretreatment NLR in bladder cancer and metastatic or unresectable urothelial carcinoma (mUC or uUC) patients up to July 2017. The correlation between the pretreatment NLR and pathological characteristics was also evaluated in bladder cancer patients. The hazard ratio (HR) and odds ratio (OR) with the 95% confidence interval (CI) were extracted or calculated from the included studies for further pooled analysis. A total of 21 studies were included in a pooled analysis. The pooled results indicated that a high pretreatment NLR was associated with reduced overall survival (OS) (HR=1.27, 95% CI=1.12-1.43), relapse-free survival (RFS) (HR=1.41, 95% CI=1.23-1.60), progression-free survival (PFS) (HR=1.75, 95% CI=1.36-2.15), disease-specific survival (DSS) and cancer-specific survival (CSS) (HR=1.27, 95% CI=1.19-1.35) in the bladder cancer patients. Additionally, an elevated pretreatment NLR suggested a worse OS rate in the mUC or uUC patients (HR=1.63, 95% CI=1.34-1.91). The pooled ORs and 95% CIs showed that a high pretreatment NLR could be a risk indicator for certain pathological features, such as lymphovascular invasion, a positive margin status and advanced tumor stage. our results showed that a high pretreatment NLR predicted poor prognosis in bladder cancer, mUC and uUC patients. © 2018 The Author(s). Published by S. Karger AG, Basel.

Magnitude and Determinants of the Ratio between Prevalence of Low Vision and Blindness in Rapid Assessment of Avoidable Blindness Surveys.

Science.gov (United States)

Kaphle, Dinesh; Lewallen, Susan

2017-10-01

To determine the magnitude and determinants of the ratio between prevalence of low vision and prevalence of blindness in rapid assessment of avoidable blindness (RAAB) surveys globally. Standard RAAB reports were downloaded from the repository or requested from principal investigators. Potential predictor variables included prevalence of uncorrected refractive error (URE) as well as gross domestic product (GDP) per capita, health expenditure per capita of the country across World Bank regions. Univariate and multivariate linear regression were used to investigate the correlation between potential predictor variables and the ratio. The results of 94 surveys from 43 countries showed that the ratio ranged from 1.35 in Mozambique to 11.03 in India with a median value of 3.90 (Interquartile range 3.06;5.38). Univariate regression analysis showed that prevalence of URE (p = 0.04), logarithm of GDP per capita (p = 0.01) and logarithm of health expenditure per capita (p = 0.03) were significantly associated with the higher ratio. However, only prevalence of URE was found to be significant in multivariate regression analysis (p = 0.03). There is a wide variation in the ratio of the prevalence of low vision to the prevalence of blindness. Eye care service utilization indicators such as the prevalence of URE may explain some of the variation across the regions.

Pb concentrations and isotope ratios of soil O and C horizons in Nord-Trøndelag, central Norway: Anthropogenic or natural sources?

International Nuclear Information System (INIS)

Reimann, C.; Fabian, K.; Flem, B.; Schilling, J.; Roberts, D.; Englmaier, P.

2016-01-01

Soil O and C horizon samples (N = 752) were collected at a sample density of 1 site/36 km"2 in Nord-Trøndelag and parts of Sør-Trøndelag (c. 25,000 km"2), and analysed for Pb and three of the four naturally occurring Pb isotopes ("2"0"6Pb, "2"0"7Pb and "2"0"8Pb) in a HNO_3/HCl extraction. Soil O and C horizons are decoupled in terms of both Pb concentrations and Pb isotope ratios. In the soil C horizon the Grong-Olden Culmination, a continuous exposure of the Precambrian crystalline basement across the general grain of the Caledonian orogen, is marked by a distinct "2"0"6Pb/"2"0"7Pb isotope ratio anomaly. No clear regional or even local patterns are detected when mapping the Pb isotope ratios in the soil O horizon samples. Variation in the isotope ratios declines significantly from the soil C to the O horizon. On average, Pb concentrations in the O horizon are four times higher and the "2"0"6Pb/"2"0"7Pb isotope ratio is shifted towards a median of 1.15 in comparison to 1.27 in the C horizon. It is demonstrated that natural processes like weathering in combination with plant uptake need to be taken into account in order to distinguish anthropogenic input from natural influences on Pb concentration and the "2"0"6Pb/"2"0"7Pb isotope ratio in the soil O horizon. - Highlights: • Lead concentrations are on average higher by a factor of 4 in the soil O than in the C horizon. • The "2"0"6Pb/"2"0"7Pb isotope ratio is considerably lower in the soil O than in the C horizon. • The observed shifts are in conflict with exclusive anthropogenic input of Pb. • The hypothesis of natural Pb-isotope invariance can not be hold.

[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.

Determination of uranium in urine - measurement of isotope ratios and quantification by use of inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Krystek, P.; Ritsema, R.

2002-01-01

For analysis of uranium in urine determination of the isotope ratio and quantification were investigated by high-resolution inductively coupled plasma mass spectrometry (HR ICP-MS). The instrument used (ThermoFinniganMAT ELEMENT2) is a single-collector MS and, therefore, a stable sample-introduction system was chosen. The methodical set-up was optimized to achieve the best precision for both the isotope ratio and the total uranium concentration in the urine matrix.Three spiked urine samples from an European interlaboratory comparison were analyzed to determine the 235 U/ 238 U isotope ratio. The ratio was found to be in the range 0.002116 to 0.007222, the latter being the natural uranium isotope ratio. The first ratio indicates the abundance of depleted uranium.The effect of storage conditions and the stability for the matrix urine were investigated by using ''real-life'' urine samples from unexposed persons in the Netherlands. For samples stored under refrigeration and acidified the results (range 0.8 to 5.3 ng L -1 U) were in the normal fluctuation range whereas a decrease in uranium concentration was observed for samples stored at room temperature without acidification. (orig.)

MEMS variable capacitance devices utilizing the substrate: I. Novel devices with a customizable tuning range

International Nuclear Information System (INIS)

Elshurafa, Amro M; El-Masry, Ezz I

2010-01-01

This paper, the first in a series of two, presents a paradigm shift in the design of MEMS parallel plate PolyMUMPS variable capacitance devices by proposing two structures that utilize the substrate and are able to provide predetermined, customizable, tuning ranges and/or ratios. The proposed structures can provide theoretical tuning ranges anywhere from 4.9 to 35 and from 3.4 to 26 respectively with a simple, yet effective, layout modification as opposed to the previously reported devices where the tuning range is fixed and cannot be varied. Theoretical analysis is carried out and verified with measurements of fabricated devices. The first proposed device possessed initially a tuning range of 4.4. Two variations of the structure having tuning ranges of 3 and 3.4, all at 1 GHz, were also successfully developed and tested. The second proposed variable capacitance device behaved as a switch.

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

Science.gov (United States)

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

2018-04-19

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

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.;

CO-ANALYSIS OF SOLAR MICROWAVE AND HARD X-RAY SPECTRAL EVOLUTIONS. I. IN TWO FREQUENCY OR ENERGY RANGES

International Nuclear Information System (INIS)

Song Qiwu; Huang Guangli; Nakajima, Hiroshi

2011-01-01

Solar microwave and hard X-ray spectral evolutions are co-analyzed in the 2000 June 10 and 2002 April 10 flares, and are simultaneously observed by the Owens-Valley Solar Array in the microwave band and by Yohkoh/Hard X-ray Telescope or RHESSI in the hard X-ray band, with multiple subpeaks in their light curves. The microwave and hard X-ray spectra are fitted by a power law in two frequency ranges of the optical thin part and two photon energy ranges, respectively. Similar to an earlier event in Shao and Huang, the well-known soft-hard-soft pattern of the lower energy range changed to the hard-soft-hard (HSH) pattern of the higher energy range during the spectral evolution of each subpeak in both hard X-ray flares. This energy dependence is actually supported by a positive correlation between the overall light curves and spectral evolution in the lower energy range, while it becomes an anti-correlation in the higher energy range. Regarding microwave data, the HSH pattern appears in the spectral evolution of each subpeak in the lower frequency range, which is somewhat similar to Huang and Nakajima. However, it returns back to the well-known pattern of soft-hard-harder for the overall spectral evolution in the higher frequency range of both events. This frequency dependence is confirmed by an anti-correlation between the overall light curves and spectral evolution in the lower frequency range, but it becomes a positive correlation in the higher frequency range. The possible mechanisms are discussed, respectively, for reasons why hard X-ray and microwave spectral evolutions have different patterns in different energy and frequency intervals.

Goats and/or cattle on Mopani veld. | C.H. | African Journal of Range ...

African Journals Online (AJOL)

This phenomenon had a marked influence on the outcome of the results of the trial. It was concluded that the use of both cattle and goats is desirable in order to utilize and control woody plants. A cattle:goat ratio of less than 1:2 should be applied if the goats are to attain optimum production. Keywords: animal performance ...

Hematology and serum chemistry reference ranges of free-ranging moose (Alces alces) in Norway.

Science.gov (United States)

Rostal, Melinda K; Evans, Alina L; Solberg, Erling J; Arnemo, Jon M

2012-07-01

Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces alces) adults, yearlings, and calves in Norway sampled from 1992-2000. Additionally, we demonstrated that both induction time and chase time were correlated with initial rectal temperature, although they were not significantly correlated with cortisol, aspartate aminotransferase, glucose, or creatine kinase. Overall, the reference ranges given here are similar to those given for American moose, with a few differences that can be attributed to environment, testing methodology, or subspecies or species status. This is the first report, to our knowledge, of reference ranges for moose in Norway.

Differential Drell-Yan measurements and Z/top-pair cross section ratios

CERN Document Server

Zinser, Markus; The ATLAS collaboration

2017-01-01

Precision measurements of the Drell-Yan production of W and Z bosons at the LHC provide a benchmark of our understanding of perturbative QCD and electroweak processes and probe the proton structure in a unique way. The ATLAS collaboration performed a precision Z/gamma* measurement at a center of mass energy of 8 TeV in the di-lepton mass range up to the TeV scale. These are performed double-differentially in dilepton mass and rapidity or dilepton mass and rapidity separation. The measurements are compared to state-of-the-art theory calculations and are found to bring strong constraints on the high x partons and the poorly constrained photon content of the proton. Z cross sections are also measured at a center-of-mass energies of 8TeV and 13TeV, and cross-section ratios to the top-quark pair production have been derived. This ratio measurement leads to a cancellation of several systematic effects and allows therefore for a high precision comparison to the theory predictions.

Sex ratio of five species of pelagic copepods from Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Saraswathy, M.; Santhakumari, V.

Sex ratio in five species from south and southeast coast of India varied remarkably. Five species were selected for the present investigation. Range in the percentage of males was from 8 to 121 in @iUndinula vulgaris@@ (Dana), 16-425 in @i...

Systematic approach to peak-to-average power ratio in OFDM

Science.gov (United States)

Schurgers, Curt

2001-11-01

OFDM multicarrier systems support high data rate wireless transmission using orthogonal frequency channels, and require no extensive equalization, yet offer excellent immunity against fading and inter-symbol interference. The major drawback of these systems is the large Peak-to-Average power Ratio (PAR) of the transmit signal, which renders a straightforward implementation very costly and inefficient. Existing approaches that attack this PAR issue are abundant, but no systematic framework or comparison between them exist to date. They sometimes even differ in the problem definition itself and consequently in the basic approach to follow. In this work, we provide a systematic approach that resolves this ambiguity and spans the existing PAR solutions. The basis of our framework is the observation that efficient system implementations require a reduced signal dynamic range. This range reduction can be modeled as a hard limiting, also referred to as clipping, where the extra distortion has to be considered as part of the total noise tradeoff. We illustrate that the different PAR solutions manipulate this tradeoff in alternative ways in order to improve the performance. Furthermore, we discuss and compare a broad range of such techniques and organize them into three classes: block coding, clip effect transformation and probabilistic.

Comments on the asymptotic treatment of tokamak MHD-stability at large aspect ratio

International Nuclear Information System (INIS)

Rebhan, E.

1980-01-01

In the asymptotic treatment of tokamak MHD stability at small inverse aspect ratio epsilon, the special case of poloidal wave number m=0 has been treated improperly in the literature for both axisymmetric and non-axisymmetric modes. In axisymmetric stability, a contribution to the perturbational vacuum field is either omitted or cancelled. In a variational stability analysis this field contribution provides σ 2 W with a correction term proportional to (1nepsilon) -1 , which may change the asymptotic range of stability and improve agreement with numerical finite-aspect-ratio results. In non-axisymmetric stability, for the perturbational vacuum field of the m=0 modes, usually the wrong of two possible solutions is chosen. It is shown why in many cases this wrong choice has no consequences on the correctness of the stability results, and circumstances are pointed out under which consequences may arise. (author)

Monitoring of international normalized ratios: comparison of community nurses with family physicians.

Science.gov (United States)

Levine, Max A; Shao, Wei; Klein, Douglas

2012-08-01

To determine whether community-based, nurse-led monitoring of the international normalized ratio (INR) in patients requiring long-term warfarin therapy was comparable to traditional physician monitoring. A retrospective cohort analysis of patients taking long-term warfarin therapy. The study used data gathered from 3 family medicine clinics in a primary care network in Edmonton, Alta. Medical records of patients currently taking warfarin were examined. Implementation of nurse-led monitoring in a primary care network in place of standard family physician INR monitoring. The degree of INR control before and after the implementation of nurse-run INR monitoring was assessed. The average proportion of time spent outside of therapeutic INR ranges, as well as the average number of days between successive INR readings, was calculated and compared. The degree of control placed patients into either a good-control group (out of range ≤ 25% of the time) or a moderate-control group (out of range > 25% of the time) and these groups were compared. Before nurse monitoring, INR values were out of range 20.4% of the time; after nurse monitoring they were out of range 19.2% of the time (P = .115); the time between sequential INR readings also did not differ before and after implementation of nurse monitoring (23.9 vs 21.6 days, P = .789). Nurse-led monitoring of INR is as effective as traditional physician monitoring. Advantages of nurse-led monitoring might include freeing family physicians to see more patients or to spend less time at work. It might also represent potential cost savings.

Escape peak ratios in silicon X-ray charge coupled devices (CCDs)

International Nuclear Information System (INIS)

McCarthy, K.J.; Owens, A.; Keay, A.

1997-01-01

The intensity of the escape peak from the CCDs developed for the Joint European X-ray Telescope (JET-X) has been investigated over the energy range 2-10 keV. Both measured and calculated escape peak ratios (i.e., the ratio of counts in the escape peak to the sum of the counts in the escape and main peaks) are found to be in excellent agreement for all event sizes (i.e., single pixel events, 1 and 2 pixel events, etc.). Using a Monte Carlo simulation the escape peak ratio has been investigated as a function of pixel size and depletion depth. For completeness, we list the energy dependent parameterised forms for five CCDs used in three major astronomy missions. (orig.)

Measurement of the antineutrino to neutrino charged-current interaction cross section ratio in MINERvA

Science.gov (United States)

Ren, L.; Aliaga, L.; Altinok, O.; Bellantoni, L.; Bercellie, A.; Betancourt, M.; Bodek, A.; Bravar, A.; Budd, H.; Cai, T.; Carneiro, M. F.; da Motta, H.; Devan, J.; Dytman, S. A.; Díaz, G. A.; Eberly, B.; Endress, E.; Felix, J.; Fields, L.; Fine, R.; Gago, A. M.; Galindo, R.; Gallagher, H.; Ghosh, A.; Golan, T.; Gran, R.; Han, J. Y.; Harris, D. A.; Hurtado, K.; Kiveni, M.; Kleykamp, J.; Kordosky, M.; Le, T.; Maher, E.; Manly, S.; Mann, W. A.; Marshall, C. M.; Martinez Caicedo, D. A.; McFarland, K. S.; McGivern, C. L.; McGowan, A. M.; Messerly, B.; Miller, J.; Mislivec, A.; Morfín, J. G.; Mousseau, J.; Naples, D.; Nelson, J. K.; Norrick, A.; Nuruzzaman, Paolone, V.; Park, J.; Patrick, C. E.; Perdue, G. N.; Ramírez, M. A.; Ransome, R. D.; Ray, H.; Rimal, D.; Rodrigues, P. A.; Ruterbories, D.; Schellman, H.; Solano Salinas, C. J.; Sultana, M.; Sánchez Falero, S.; Valencia, E.; Walton, T.; Wolcott, J.; Wospakrik, M.; Yaeggy, B.; MinerνA Collaboration

2017-04-01

We present measurements of the neutrino and antineutrino total charged-current cross sections on carbon and their ratio using the MINERvA scintillator-tracker. The measurements span the energy range 2-22 GeV and were performed using forward and reversed horn focusing modes of the Fermilab low-energy NuMI beam to obtain large neutrino and antineutrino samples. The flux is obtained using a subsample of charged-current events at low hadronic energy transfer along with precise higher energy external neutrino cross section data overlapping with our energy range between 12-22 GeV. We also report on the antineutrino-neutrino cross section ratio, RCC , which does not rely on external normalization information. Our ratio measurement, obtained within the same experiment using the same technique, benefits from the cancellation of common sample systematic uncertainties and reaches a precision of ˜5 % at low energy. Our results for the antineutrino-nucleus scattering cross section and for RCC are the most precise to date in the energy range Eν<6 GeV .

The thermal history of char as disclosed by carbon isotope ratios

DEFF Research Database (Denmark)

Egsgaard, Helge; Ambus, Per; Ahrenfeldt, Jesper

In laboratory experiments, biomass char was produced under controlled conditions using wood chips from French pinewood. Different char qualities were obtained by pyrolysing the biomass at similar heating rates with end-temperatures ranging from 250 to 1000 o C. The char was analysed by flash...... pyrolysis and isotope ratio mass spectrometry. The results demonstrate that the temperature history of the char is reflected in the fine variation of carbon isotopes. The compound classes responsible for the variation were identified. Key words: Isotope ratio, flash pyrolysis, hot gas cleaning...

Divergence-ratio axi-vision camera (Divcam): A distance mapping camera

International Nuclear Information System (INIS)

Iizuka, Keigo

2006-01-01

A novel distance mapping camera the divergence-ratio axi-vision camera (Divcam) is proposed. The decay rate of the illuminating light with distance due to the divergence of the light is used as means of mapping the distance. Resolutions of 10 mm over a range of meters and 0.5 mm over a range of decimeters were achieved. The special features of this camera are its high resolution real-time operation, simplicity, compactness, light weight, portability, and yet low fabrication cost. The feasibility of various potential applications is also included

Geochemistry of tholeiitic and alkalic lavas from the Koolau Range, Oahu, Hawaii

International Nuclear Information System (INIS)

Roden, M.F.; Frey, F.A.

1984-01-01

Lavas of the post-erosional, alkalic Honolulu Volcanics have significantly lower 87 Sr/ 86 Sr and higher 143 Nd/ 144 Nd than the older and underlying Koolau tholeiites which form the Koolau shield of eastern Oahu, Hawaii. Despite significant compositional variation within lavas forming the Honolulu Volcanics, these lavas are isotopically (Sr, Nd, Pb) very similar which contrasts with the isotopic heterogeneity of the Koolau tholeiites. Among Hawaiian tholeiitic suites, the Koolau lavas are geochemically distinct because of their lower iron contents and Sr and Nd isotopic ratios which range to bulk earth values. These geochemical data preclude simple models such as derivation of the Honolulu Volcanics and Koolau tholeiites from a common source by different degrees of melting or by mixing of two geochemically distinct sources. There may be no genetic relationship between the origin and evolution of these two lava suites; however, the trend shown by Koolau Range lavas of increasing 143 Nd/ 144 Nd and decreasing 87 Sr/ 86 Sr with decreasing eruption age and increasing alkalinity also occurs at Haleakala, East Molokai and Kauai volcaneoes. A complex mixing model proposed for Haleakala lavas can account for the variations in Sr and Nd isotopic ratios and processes occurring during ascent of relatively enriched mantle through relatively depleted MORB-related lithosphere. Although two isotopically distinct components may be sufficient to explain Sr and Nd isotopic variations at individual Hawaiian volcaneoes, more than two isotopically distinct materials are required to explain variations of Sr, Nd and Pb isotopic ratios in all Hawaiian lavas. (orig.)

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

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

THE STAR FORMATION HISTORIES OF RED-SEQUENCE GALAXIES, MASS-TO-LIGHT RATIOS AND THE FUNDAMENTAL PLANE

International Nuclear Information System (INIS)

Allanson, Steven P.; Hudson, Michael J.; Smith, Russell J.; Lucey, John R.

2009-01-01

This paper addresses the challenge of understanding the typical star formation histories of red-sequence galaxies, using linestrength indices and mass-to-light ratios as complementary constraints on their stellar age distribution. We first construct simple parametric models of the star formation history that bracket a range of scenarios, and fit these models to the linestrength indices of low-redshift cluster red-sequence galaxies. For giant galaxies, we confirm the downsizing trend, i.e., the stellar populations are younger, on average, for lower σ galaxies. We find, however, that this trend flattens or reverses at σ ∼ -1 . We then compare predicted stellar mass-to-light ratios with dynamical mass-to-light ratios derived from the fundamental plane (FP), or by the SAURON group. For galaxies with σ ∼ 70 km s -1 , models with a late 'frosting' of young stars and models with exponential star formation histories have stellar mass-to-light ratios that are larger than observed dynamical mass-to-light ratios by factors of 1.7 and 1.4, respectively, and so are rejected. The single stellar population (SSP) model is consistent with the FP, and requires a modest amount of dark matter (between 20% and 30%) to account for the difference between stellar and dynamical mass-to-light ratios. A model in which star formation was 'quenched' at intermediate ages is also consistent with the observations, although in this case less dark matter is required for low mass galaxies. We also find that the contribution of stellar populations to the 'tilt' of the fundamental plane is highly dependent on the assumed star formation history: for the SSP model, the tilt of the FP is driven primarily by stellar-population effects. For a quenched model, two-thirds of the tilt is due to stellar populations and only one-third is due to dark matter or non-homology.

Effect of Processing Delay and Storage Conditions on Urine Albumin-to-Creatinine Ratio.

Science.gov (United States)

Herrington, William; Illingworth, Nicola; Staplin, Natalie; Kumar, Aishwarya; Storey, Ben; Hrusecka, Renata; Judge, Parminder; Mahmood, Maria; Parish, Sarah; Landray, Martin; Haynes, Richard; Baigent, Colin; Hill, Michael; Clark, Sarah

2016-10-07

Because there is substantial biologic intraindividual variation in albumin excretion, randomized trials of albuminuria-reducing therapies may need multiple urine samples to estimate daily urinary albumin excretion. Mailing spot urine samples could offer a convenient and cost-effective method to collect multiple samples, but urine albumin-to-creatinine ratio stability in samples stored at ambient temperatures for several days is unknown. Patients with kidney disease provided fresh urine samples in two tubes (with and without boric acid preservative). Reference aliquots from each participant were analyzed immediately, whereas remaining aliquots were subject to different handling/storage conditions before analysis, including delayed processing for up to 7 days at three different storage temperatures (4°C, 18°C, and 30°C), multiple freeze-thaw cycles, and long-term frozen storage at -80°C, -40°C, and -20°C. We calculated the mean percentage change in urine albumin-to-creatinine ratio for each condition, and we considered samples stable if the 95% confidence interval was within a ±5% threshold. Ninety-three patients provided samples with detectable albuminuria in the reference aliquot. Median (interquartile range) urine albumin-to-creatinine ratio was 87 (20-499) mg/g. The inclusion of preservative had minimal effect on fresh urine albumin-to-creatinine ratio measurements but reduced the changes in albumin and creatinine in samples subject to processing delay and storage conditions. The urine albumin-to-creatinine ratio was stable for 7 days in samples containing preservative at 4°C and 18°C and 2 days when stored at 30°C. It was also stable in samples with preservative after three freeze-thaw cycles and in frozen storage for 6 months at -80°C or -40°C but not at -20°C. Mailed urine samples collected with preservative and received within 7 days if ambient temperature is ≤18°C, or within 2 days if the temperature is higher but does not exceed 30°C, are

Fatigue crack growth threshold as a design criterion - statistical scatter and load ratio in the Kitagawa-Takahashi diagram

International Nuclear Information System (INIS)

Kolitsch, S.; Gänser, H.-P.; Maierhofer, J.; Pippan, R.

2016-01-01

Cracks in components reduce the endurable stress so that the endurance limit obtained from common smooth fatigue specimens cannot be used anymore as a design criterion. In such cases, the Kitagawa-Takahashi diagram can be used to predict the admissible stress range for infinite life, at a given crack length and stress range. This diagram is constructed for a single load ratio R. However, in typical mechanical engineering applications, the load ratio R varies widely due to the applied load spectra and residual stresses. In the present work an extended Kitagawa-Takahashi diagram accounting for crack length, crack extension and load ratio is constructed. To describe the threshold behaviour of short cracks, a master resistance curve valid for a wide range of steels is developed using a statistical approach. (paper)

Ratio manipulating spectrophotometry versus chemometry as stability indicating methods for cefquinome sulfate determination.

Science.gov (United States)

Yehia, Ali M; Arafa, Reham M; Abbas, Samah S; Amer, Sawsan M

2016-01-15

Spectral resolution of cefquinome sulfate (CFQ) in the presence of its degradation products was studied. Three selective, accurate and rapid spectrophotometric methods were performed for the determination of CFQ in the presence of either its hydrolytic, oxidative or photo-degradation products. The proposed ratio difference, derivative ratio and mean centering are ratio manipulating spectrophotometric methods that were satisfactorily applied for selective determination of CFQ within linear range of 5.0-40.0 μg mL(-1). Concentration Residuals Augmented Classical Least Squares was applied and evaluated for the determination of the cited drug in the presence of its all degradation products. Traditional Partial Least Squares regression was also applied and benchmarked against the proposed advanced multivariate calibration. Experimentally designed 25 synthetic mixtures of three factors at five levels were used to calibrate and validate the multivariate models. Advanced chemometrics succeeded in quantitative and qualitative analyses of CFQ along with its hydrolytic, oxidative and photo-degradation products. The proposed methods were applied successfully for different pharmaceutical formulations analyses. These developed methods were simple and cost-effective compared with the manufacturer's RP-HPLC method. Copyright © 2015 Elsevier B.V. All rights reserved.

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

Range-energy relations and stopping power of water, water vapour and tissue equivalent liquid for α particles over the energy range 0.5 to 8 MeV

International Nuclear Information System (INIS)

Palmer, R.B.J.; Akhavan-Rezayat, Ahmad

1978-01-01

Experimental range-energy relations are presented for alpha particles in water, water vapour and tissue equivalent liquid at energies up to 8 MeV. From these relations differential stopping powers are derived at 0.25 MeV energy intervals. Consideration is given to sources of error in the range-energy measurements and to the uncertainties that these will introduce into the stopping power values. The ratio of the differential stopping power of muscle equivalent liquid to that of water over the energy range 0.5 to 7.5 MeV is discussed in relation to the specific gravity and chemical composition of the muscle equivalent liquid. Theoretical molecular stopping power calculations based upon the Bethe formula are also presented for water. The effect of phase upon the stopping power of water is discussed. The molecular stopping power of water vapour is shown to be significantly higher than that of water for energies below 1.25 MeV and above 2.5 MeV, the ratio of the two stopping powers rising to 1.39 at 0.5 MeV and to 1.13 at 7.0 MeV. Stopping power measurements for other liquids and vapours are compared with the results for water and water vapour and some are observed to have stopping power ratios in the vapour and liquid phases which vary with energy in a similar way to water. It is suggested that there may be several factors contributing to the increased stopping power of liquids. The need for further experimental results on a wider range of liquids is stressed

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.

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

Visible-near-infrared spectroscopy can predict the clay/organic carbon and mineral fines/organic carbon ratios

DEFF Research Database (Denmark)

Hermansen, Cecilie; Knadel, Maria; Møldrup, Per

2016-01-01

The ratios of mineral fines (carbon (OC), consisting of the n-ratio (i.e., the clay/OC ratio) and m-ratio (i.e., the fines/OC ratio) have recently been used to analyze and predict soil functional properties such as tilth conditions, clay dispersibility, degree...... from seven Danish and one Greenlandic fields, with a large textural range (clay: 0.027–0.355 kg kg−1; OC: 0.011–0.084 kg kg−1; n-ratio: 0.49–16.80; m-ratio: 1.46–32.14), were analyzed for texture and OC and subsequently scanned with a vis-NIR spectrometer from 400 to 2500 nm. The spectral data were...

Improvement of trans-sialylation versus hydrolysis activity of an engineered sialidase from Trypanosoma rangeli by use of co-solvents

DEFF Research Database (Denmark)

Zeuner, Birgitte; Riisager, Anders; Mikkelsen, Jørn Dalgaard

2014-01-01

hexafluorophosphate), were examined as co-solvents for the improvement of the synthesis versus hydrolysis ratio in the trans-sialylation of lactose, catalysed by an engineered sialidase from Trypanosoma rangeli. The use of 25 % (v/v) t-butanol as co-solvent significantly increased 3'-sialyllactose production by 40...... % from 1.04 ± 0.09 to 1.47 ± 0.01 mM. The synthesis versus hydrolysis ratio increased correspondingly by 1.2-times. 1-2.5 % (v/v) EAN or [C2OHMIm][PF6] improved the synthesis versus hydrolysis ratio up to 2.5-times but simultaneously decreased the 3'-sialyllactose yield, probably due to enzyme...... inactivation caused by the ionic liquid. [MMIm][MeSO4] had a detrimental effect on the trans-sialylation yield and on the ratio between synthesis and hydrolysis....

High-q microring resonator with narrow free spectral range for pulse repetition rate multiplication

DEFF Research Database (Denmark)

Pu, Minhao; Ji, Hua; Frandsen, Lars Hagedorn

2009-01-01

We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz.......We demonstrate a silicon-on-insulator microring resonator with a free-spectral-range of 0.32 nm, an extinction ratio of 27 dB, and a quality factor of ~140900 at 1550 nm that is used for pulse repetition-rate multiplication from 10 to 40 GHz....

High aspect ratio MEMS capacitor for high frequency impedance matching applications

DEFF Research Database (Denmark)

Yalcinkaya, Arda Deniz; Jensen, Søren; Hansen, Ole

2003-01-01

We present a microelectromechanical tunable capacitor with a low control voltage, a wide tuning range and adequate electrical quality factor. The device is fabricated in a single-crystalline silicon layer using deep reactive ion etching (DRIE) for obtaining high-aspect ratio (> 20) parallel comb...

Factors which define the α/γ ratio in CsI:Tl crystals

International Nuclear Information System (INIS)

Kudin, Alexander M.; Sysoeva, Elena P.; Sysoeva, Elena V.; Trefilova, Larisa N.; Zosim, Dmitry I.

2005-01-01

Dependences of light yield and α/γ ratio on the Tl concentration have been studied within a wide range of shaping times. It is shown that the α/γ ratio essentially depends on the Tl concentration. Proper combination of the Tl concentration and optimum shaping time in electronics allows to obtain detectors with rather high light output for γ-rays, α-particles and α/γ ratio values. It has been shown that both the light yield at α-excitation and the α/γ-ratio depend on the time of crystal storage after polishing. On the basis of the idea of the formation of deformation-induced point defects in a thin surface-adjacent layer, the causes of the temporary increasing in light yield for α-particle are explained. An explanation is given of the results obtained by Gwin and Murray concerning the fact that the α/γ ratio is practically independent on Tl concentration

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

Determination of 240Pu/239Pu isotope ratios in Kara Sea and Novaya Zemlya sediments using accelerator mass spectrometry

International Nuclear Information System (INIS)

Oughton, D.H.; Skipperud, L.; Salbu, B.; Fifield, L.K.; Cresswell, R.C.; Day, J.P.

1999-01-01

Accelerator mass spectrometry (AMS) has been used to determine Pu activity concentrations and 240 Pu/ 239 Pu isotope ratios in sediments from the Kara Sea and radioactive waste dumping sites at Novaya Zemlya. Measured 239,240 Pu activities ranged from 0.06 - 9.8 Bq/kg dry weight, 240 Pu/ 239 Pu atom ratios ranged from 0.13 to 0.28, and 238 Pu/ 239,240 Pu activity ratios from 0.02 to 0.6. Perturbations from global fallout isotope ratios were evident at three sites: the Yenisey Estuary and Abrosimov Fjords where 240 Pu/ 239 Pu ratios were lower (0.13-0.14); and Stepovogo Fjord sediments where ratios were higher (up to 0.28) than fallout ratios. Based on procedural blanks, detection limits for AMS were below 1 fg Pu and the method showed good precision for isotope ratio measurements, minimal matrix, interference and memory effects. For high level samples, comparison between alpha spectrometry and AMS gave good agreement for measurement of 239,240 Pu activity concentrations. (author)

Determination of hydrogen/deuterium ratio with neutron measurements on MAST

Energy Technology Data Exchange (ETDEWEB)

Klimek, I., E-mail: iwona.klimek@physics.uu.se; Cecconello, M.; Ericsson, G. [Department of Physics and Astronomy, Uppsala University, Uppsala (Sweden); Sharapov, S. E.; Harrison, J. [CCFE, Culham Science Centre, Abingdon (United Kingdom)

2014-11-15

On MAST, compressional Alfvén eigenmodes can be destabilized by the presence of a sufficiently large population of energetic particles in the plasma. This dependence was studied in a series of very similar discharges in which increasing amounts of hydrogen were puffed into a deuterium plasma. A simple method to estimate the isotopic ratio n{sub H}/n{sub D} using neutron emission measurements is here described. The inferred isotopic ratio ranged from 0.0 to 0.6 and no experimental indication of changes in radial profile of n{sub H}/n{sub D} were observed. These findings are confirmed by TRANSP/NUBEAM simulations of the neutron emission.

Signal-to-noise ratios of multiplexing spectrometers in high backgrounds

Science.gov (United States)

Knacke, R. F.

1978-01-01

Signal-to-noise ratios and the amount of multiplexing gain achieved with a Michelson spectrometer during detector and background noise are studied. Noise caused by the warm background is found in 10 and 20-micron atmospheric windows in high resolution Fourier spectroscopy. An equation is derived for the signal-to-noise ratio based on the number of channels, total time to obtain the complete spectrum, the signal power in one spectral element, and the detector noise equivalent power in the presence of negligible background. Similar expressions are derived for backgrounds yielding a noise equivalent power to a spectral element, and backgrounds having flat spectra in the frequency range under investigation.

Effects of exposure to 56Fe particles of protons on fixed-ratio operant responding in rats

International Nuclear Information System (INIS)

Rabin, B.M.; Buhler, L.L.; Jenkins, D.G.; Joseph, J.A.; Shukitt-Hale, B.

2002-01-01

On long-duration trips outside of the magnetosphere, astronauts will be exposed to protons and to heavy particles which can affect their performance of required tasks. It is essential to determine the range of behaviors that might be affected by exposure to these types of radiation in order to understand the nature of behavioral deficits and to develop effective countermeasures. The present experiment examined the ability of rats to make an operant response following exposure to protons (250 MeV, 4 Gy) or 56 Fe particles (1 GeV/n, 1 or 2 Gy). Following irradiation, rats were trained to press a lever in order to obtain food reinforcement. They were then placed on an ascending fixed-ratio schedule from FR-1 (each lever press rewarded with a food pellet) through FR-35 (35 lever presses required for 1 food pellet). Rats exposed to 4 Gy of protons or 1 Gy of 56 Fe particles responded similarly to controls, increasing their rate of responding as the ratio increased. However, rats exposed to 2 Gy of 56 Fe particles failed to increase their rate of responding at ratios greater than FR-20, indicating that rats exposed to 2 Gy of 56 Fe particles cannot respond appropriately to increasing work requirements. (author)

Does Height to Width Ratio Correlate with Mean Volume in Gastropods?

Science.gov (United States)

Barriga, R.; Seixas, G.; Payne, J.

2012-12-01

Marine organisms' shell shape and size show important biological information. For example, shape and size can dictate how the organism ranges for food and escapes predation. Due to lack of data and analysis, the evolution of shell size in marine gastropods (snails) remains poorly known. In this study, I attempt to find the relationship between height to width ratio and mean volume. I collected height and width measurements from primary literature sources and calculated volume from these measurements. My results indicate that there was no correlation between height to width ratio and mean volume between 500 to 200 Ma, but there was a correlation between 200 Ma to present where there is a steady increase in both height to width ratio and mean volume. This means that shell shape was not an important factor at the beginning of gastropod evolution but after 200 Ma body size evolution was increasingly driven by the height to width ratio.

Increased power to weight ratio of piezoelectric energy harvesters through integration of cellular honeycomb structures

International Nuclear Information System (INIS)

Chandrasekharan, N; Thompson, L L

2016-01-01

The limitations posed by batteries have compelled the need to investigate energy harvesting methods to power small electronic devices that require very low operational power. Vibration based energy harvesting methods with piezoelectric transduction in particular has been shown to possess potential towards energy harvesters replacing batteries. Current piezoelectric energy harvesters exhibit considerably lower power to weight ratio or specific power when compared to batteries the harvesters seek to replace. To attain the goal of battery-less self-sustainable device operation the power to weight ratio gap between piezoelectric energy harvesters and batteries need to be bridged. In this paper the potential of integrating lightweight honeycomb structures with existing piezoelectric device configurations (bimorph) towards achieving higher specific power is investigated. It is shown in this study that at low excitation frequency ranges, replacing the solid continuous substrate of conventional bimorph with honeycomb structures of the same material results in a significant increase in power to weight ratio of the piezoelectric harvester. At higher driving frequency ranges it is shown that unlike the traditional piezoelectric bimorph with solid continuous substrate, the honeycomb substrate bimorph can preserve optimum global design parameters through manipulation of honeycomb unit cell parameters. Increased operating lifetime and design flexibility of the honeycomb core piezoelectric bimorph is demonstrated as unit cell parameters of the honeycomb structures can be manipulated to alter mass and stiffness properties of the substrate, resulting in unit cell parameter significantly influencing power generation. (paper)

MEMS variable capacitance devices utilizing the substrate: I. Novel devices with a customizable tuning range

KAUST Repository

Elshurafa, Amro M.

2010-03-22

This paper, the first in a series of two, presents a paradigm shift in the design of MEMS parallel plate PolyMUMPS variable capacitance devices by proposing two structures that utilize the substrate and are able to provide predetermined, customizable, tuning ranges and/or ratios. The proposed structures can provide theoretical tuning ranges anywhere from 4.9 to 35 and from 3.4 to 26 respectively with a simple, yet effective, layout modification as opposed to the previously reported devices where the tuning range is fixed and cannot be varied. Theoretical analysis is carried out and verified with measurements of fabricated devices. The first proposed device possessed initially a tuning range of 4.4. Two variations of the structure having tuning ranges of 3 and 3.4, all at 1 GHz, were also successfully developed and tested. The second proposed variable capacitance device behaved as a switch. © 2010 IOP Publishing Ltd.

Nitrogen to phosphorus ratio of plant biomass versus soil solution in a tropical pioneer tree, Ficus insipida.

Science.gov (United States)

Garrish, Valerie; Cernusak, Lucas A; Winter, Klaus; Turner, Benjamin L

2010-08-01

It is commonly assumed that the nitrogen to phosphorus (N:P) ratio of a terrestrial plant reflects the relative availability of N and P in the soil in which the plant grows. Here, this was assessed for a tropical pioneer tree, Ficus insipida. Seedlings were grown in sand and irrigated with nutrient solutions containing N:P ratios ranging from 100. The experimental design further allowed investigation of physiological responses to N and P availability. Homeostatic control over N:P ratios was stronger in leaves than in stems or roots, suggesting that N:P ratios of stems and roots are more sensitive indicators of the relative availability of N and P at a site than N:P ratios of leaves. The leaf N:P ratio at which the largest plant dry mass and highest photosynthetic rates were achieved was approximately 11, whereas the corresponding whole-plant N:P ratio was approximately 6. Plant P concentration varied as a function of transpiration rate at constant nutrient solution P concentration, possibly due to transpiration-induced variation in the mass flow of P to root surfaces. The transpiration rate varied in response to nutrient solution N concentration, but not to nutrient solution P concentration, demonstrating nutritional control over transpiration by N but not P. Water-use efficiency varied as a function of N availability, but not as a function of P availability.

Hematology and serum chemistry reference ranges of free-ranging moose (Alces Alces) in Norway

OpenAIRE

Rostal, Melinda K.; Evans, Alina L.; Solberg, Erling L.; Arnemo, Jon Martin

2012-01-01

This article is also available here: http://www.jwildlifedis.org/ Baseline reference ranges of serum chemistry and hematology data can be important indicators for the status of both individuals or populations of wild animals that are affected by emerging pathogens, toxicants, or other causes of disease. Frequently, reference ranges for these values are not available for wildlife species or subspecies. We present hematologic and serum chemistry reference ranges for moose (Alces ...

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

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

Science.gov (United States)

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

2013-04-01

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

TL glow ratios at different temperature intervals of integration in thermoluminescence method. Comparison of Japanese standard (MHLW notified) method with CEN standard methods

International Nuclear Information System (INIS)

Todoriki, Setsuko; Saito, Kimie; Tsujimoto, Yuka

2008-01-01

The effect of the integration temperature intervals of TL intensities on the TL glow ratio was examined in comparison of the notified method of the Ministry of Health, Labour and Welfare (MHLW method) with EN1788. Two kinds of un-irradiated geological standard rock and three kinds of spices (black pepper, turmeric, and oregano) irradiated at 0.3 kGy or 1.0 kGy were subjected to TL analysis. Although the TL glow ratio exceeded 0.1 in the andesite according to the calculation of the MHLW notified method (integration interval; 70-490degC), the maximum of the first glow were observed at 300degC or more, attributed the influence of the natural radioactivity and distinguished from food irradiation. When the integration interval was set to 166-227degC according to EN1788, the TL glow ratios became remarkably smaller than 0.1, and the evaluation of the un-irradiated sample became more clear. For spices, the TL glow ratios by the MHLW notified method fell below 0.1 in un-irradiated samples and exceeded 0.1 in irradiated ones. Moreover, Glow1 maximum temperatures of the irradiated samples were observed at the range of 168-196degC, and those of un-irradiated samples were 258degC or more. Therefore, all samples were correctly judged by the criteria of the MHLW method. However, based on the temperature range of integration defined by EN1788, the TL glow ratio of un-irradiated samples remarkably became small compared with that of the MHLW method, and the discrimination of the irradiated sample from non-irradiation sample became clearer. (author)

Age estimation by pulp/tooth ratio in lower premolars by orthopantomography.

Science.gov (United States)

Cameriere, Roberto; De Luca, Stefano; Alemán, Inmaculada; Ferrante, Luigi; Cingolani, Mariano

2012-01-10

Accurate age estimation has always been a problem for forensic scientists, and apposition of secondary dentine is often used as an indicator of age. Since 2004, in order to examine patterns of secondary dentine apposition, Cameriere et al. have been extensively studying the pulp/tooth area ratio of the canines by panoramic and peri-apical X-ray images. The main aim of this paper is to examine the relationship between age and age-related changes in the pulp/tooth area ratio in monoradicular teeth, with the exception of canines, by orthopantomography. A total of 606 orthopantomograms of Spanish white Caucasian patients (289 women and 317 men), aged between 18 and 75 years and coming from Bilbao and Granada (Spain), was analysed. Regression analysis of age of monoradicular teeth indicated that the lower premolars were the most closely correlated with age. An ANCOVA did not show significant differences between men and women. Multiple regression analysis, with age as dependent variable and pulp/tooth area ratio as predictor, yielded several formulae. R(2) ranged from 0.69 to 0.75 for a single lower premolar tooth and from 0.79 to 0.86 for multiple lower premolar teeth. Depending on the available number of premolar teeth, the mean of the absolute values of residual standard error, at 95% confidence interval, ranged between 4.34 and 6.02 years, showing that the pulp/tooth area ratio is a useful variable for assessing age with reasonable accuracy. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Measurement of 233U/234U ratios in contaminated groundwater using alpha spectrometry

International Nuclear Information System (INIS)

Harrison, Jennifer J.; Payne, Timothy E.; Wilsher, Kerry L.; Thiruvoth, Sangeeth; Child, David P.; Johansen, Mathew P.; Hotchkis, Michael A.C.

2016-01-01

The uranium isotope 233 U is not usually observed in alpha spectra from environmental samples due to its low natural and fallout abundance. It may be present in samples from sites in the vicinity of nuclear operations such as reactors or fuel reprocessing facilities, radioactive waste disposal sites or sites affected by clandestine nuclear operations. On an alpha spectrum, the two most abundant alpha emissions of 233 U (4.784 MeV, 13.2%; and 4.824 MeV, 84.3%) will overlap with the 234 U doublet peak (4.722 MeV, 28.4%; and 4.775 MeV, 71.4%), if present, resulting in a combined 233+234 U multiplet. A technique for quantifying both 233 U and 234 U from alpha spectra was investigated. A series of groundwater samples were measured both by accelerator mass spectrometry (AMS) to determine 233 U/ 234 U atom and activity ratios and by alpha spectrometry in order to establish a reliable 233 U estimation technique using alpha spectra. The Genie™ 2000 Alpha Analysis and Interactive Peak Fitting (IPF) software packages were used and it was found that IPF with identification of three peaks ( 234 U minor, combined 234 U major and 233 U minor, and 233 U major) followed by interference correction on the combined peak and a weighted average activity calculation gave satisfactory agreement with the AMS data across the 233 U/ 234 U activity ratio range (0.1–20) and 233 U activity range (2–300 mBq) investigated. Correlation between the AMS 233 U and alpha spectrometry 233 U was r 2  = 0.996 (n = 10). - Highlights: • Describes a technique for deconvoluting the combined 233 U and 234 U multiplet in alpha spectra. • Enables 233 U and 234 U activities and 233 U/ 234 U ratios to be quantified without requiring additional analysis and measurement. • Applicable to an environmental matrix (groundwater) using standard alpha spectrometry counting equipment, operation and set-up.

Effect of home testing of international normalized ratio on clinical events.

Science.gov (United States)

Matchar, David B; Jacobson, Alan; Dolor, Rowena; Edson, Robert; Uyeda, Lauren; Phibbs, Ciaran S; Vertrees, Julia E; Shih, Mei-Chiung; Holodniy, Mark; Lavori, Philip

2010-10-21

Warfarin anticoagulation reduces thromboembolic complications in patients with atrial fibrillation or mechanical heart valves, but effective management is complex, and the international normalized ratio (INR) is often outside the target range. As compared with venous plasma testing, point-of-care INR measuring devices allow greater testing frequency and patient involvement and may improve clinical outcomes. We randomly assigned 2922 patients who were taking warfarin because of mechanical heart valves or atrial fibrillation and who were competent in the use of point-of-care INR devices to either weekly self-testing at home or monthly high-quality testing in a clinic. The primary end point was the time to a first major event (stroke, major bleeding episode, or death). The patients were followed for 2.0 to 4.75 years, for a total of 8730 patient-years of follow-up. The time to the first primary event was not significantly longer in the self-testing group than in the clinic-testing group (hazard ratio, 0.88; 95% confidence interval, 0.75 to 1.04; P=0.14). The two groups had similar rates of clinical outcomes except that the self-testing group reported more minor bleeding episodes. Over the entire follow-up period, the self-testing group had a small but significant improvement in the percentage of time during which the INR was within the target range (absolute difference between groups, 3.8 percentage points; P<0.001). At 2 years of follow-up, the self-testing group also had a small but significant improvement in patient satisfaction with anticoagulation therapy (P=0.002) and quality of life (P<0.001). As compared with monthly high-quality clinic testing, weekly self-testing did not delay the time to a first stroke, major bleeding episode, or death to the extent suggested by prior studies. These results do not support the superiority of self-testing over clinic testing in reducing the risk of stroke, major bleeding episode, and death among patients taking warfarin

Practical guidance for conducting mediation analysis with multiple mediators using inverse odds ratio weighting.

Science.gov (United States)

Nguyen, Quynh C; Osypuk, Theresa L; Schmidt, Nicole M; Glymour, M Maria; Tchetgen Tchetgen, Eric J

2015-03-01

Despite the recent flourishing of mediation analysis techniques, many modern approaches are difficult to implement or applicable to only a restricted range of regression models. This report provides practical guidance for implementing a new technique utilizing inverse odds ratio weighting (IORW) to estimate natural direct and indirect effects for mediation analyses. IORW takes advantage of the odds ratio's invariance property and condenses information on the odds ratio for the relationship between the exposure (treatment) and multiple mediators, conditional on covariates, by regressing exposure on mediators and covariates. The inverse of the covariate-adjusted exposure-mediator odds ratio association is used to weight the primary analytical regression of the outcome on treatment. The treatment coefficient in such a weighted regression estimates the natural direct effect of treatment on the outcome, and indirect effects are identified by subtracting direct effects from total effects. Weighting renders treatment and mediators independent, thereby deactivating indirect pathways of the mediators. This new mediation technique accommodates multiple discrete or continuous mediators. IORW is easily implemented and is appropriate for any standard regression model, including quantile regression and survival analysis. An empirical example is given using data from the Moving to Opportunity (1994-2002) experiment, testing whether neighborhood context mediated the effects of a housing voucher program on obesity. Relevant Stata code (StataCorp LP, College Station, Texas) is provided. © The Author 2015. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Photopolymerization of highly filled dimethacrylate-based composites using Type I or Type II photoinitiators and varying co-monomer ratios.

Science.gov (United States)

Randolph, Luc D; Steinhaus, Johannes; Möginger, Bernhard; Gallez, Bernard; Stansbury, Jeffrey; Palin, William M; Leloup, Gaëtane; Leprince, Julian G

2016-02-01

The use of a Type I photoinitiator (monoacylphosphine oxide, MAPO) was described as advantageous in a model formulation, as compared to the conventional Type II photoinitiator (Camphorquinone, CQ). The aim of the present work was to study the kinetics of polymerization of various composite mixtures (20-40-60-80 mol%) of bisphenol A glycidyl dimethacrylate/triethylene glycol dimethacrylate (BisGMA/TegDMA) containing either CQ or MAPO, based on real-time measurements and on the characterization of various post-cure characteristics. Polymerization kinetics were monitored by Fourier-transform near-infrared spectroscopy (FT-NIRS) and dielectric analysis (DEA). A range of postcure properties was also investigated. FT-NIRS and DEA proved complementary to follow the fast kinetics observed with both systems. Autodecceleration occurred after ≈1 s irradiation for MAPO-composites and ≈5-10 s for CQ-composites. Conversion decreased with increasing initial viscosity for both photoinitiating systems. However despite shorter light exposure (3s for MAPO vs 20s for CQ-composites), MAPO-composites yielded higher conversions for all co-monomer mixtures, except at 20 mol% BisGMA, the less viscous material. MAPO systems were associated with increased amounts of trapped free radicals, improved flexural strength and modulus, and reduced free monomer release for all co-monomer ratios, except at 20 mol% BisGMA. This work confirms the major influence of the initiation system both on the conversion and network cross-linking of highly-filled composites, and further highlights the advantages of using MAPO photoinitiating systems in highly-filled dimethacrylate-based composites provided that sufficient BisGMA content (>40 mol%) and adapted light spectrum are used. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Predicted versus observed cosmic-ray-produced noble gases in lunar samples: improved Kr production ratios

International Nuclear Information System (INIS)

Regnier, S.; Hohenberg, C.M.; Marti, K.; Reedy, R.C.

1979-01-01

New sets of cross sections for the production of krypton isotopes from targets of Rb, Sr, Y, and Zr were constructed primarily on the bases of experimental excitation functions for Kr production from Y. These cross sections were used to calculate galactic-cosmic-ray and solar-proton production rates for Kr isotopes in the moon. Spallation Kr data obtained from ilmenite separates of rocks 10017 and 10047 are reported. Production rates and isotopic ratios for cosmogenic Kr observed in ten well-documented lunar samples and in ilmenite separates and bulk samples from several lunar rocks with long but unknown irradiation histories were compared with predicted rates and ratios. The agreements were generally quite good. Erosion of rock surfaces affected rates or ratios for only near-surface samples, where solar-proton production is important. There were considerable spreads in predicted-to-observed production rates of 83 Kr, due at least in part to uncertainties in chemical abundances. The 78 Kr/ 83 Kr ratios were predicted quite well for samples with a wide range of Zr/Sr abundance ratios. The calculated 80 Kr/ 83 Kr ratios were greater than the observed ratios when production by the 79 Br(n,γ) reaction was included, but were slightly undercalculated if the Br reaction was omitted; these results suggest that Br(n,γ)-produced Kr is not retained well by lunar rocks. The productions of 81 Kr and 82 Kr were overcalculated by approximately 10% relative to 83 Kr. Predicted-to-observed 84 Kr/ 83 ratios scattered considerably, possibly because of uncertainties in corrections for trapped and fission components and in cross sections for 84 Kr production. Most predicted 84 Kr and 86 Kr production rates were lower than observed. Shielding depths of several Apollo 11 rocks were determined from the measured 78 Kr/ 83 Kr ratios of ilmenite separates. 4 figures, 5 tables

BINARY CEPHEIDS: SEPARATIONS AND MASS RATIOS IN 5 M ☉ BINARIES

International Nuclear Information System (INIS)

Evans, Nancy Remage; Karovska, Margarita; Tingle, Evan; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.

2013-01-01

Deriving the distribution of binary parameters for a particular class of stars over the full range of orbital separations usually requires the combination of results from many different observing techniques (radial velocities, interferometry, astrometry, photometry, direct imaging), each with selection biases. However, Cepheids—cool, evolved stars of ∼5 M ☉ —are a special case because ultraviolet (UV) spectra will immediately reveal any companion star hotter than early type A, regardless of the orbital separation. We have used International Ultraviolet Explorer UV spectra of a complete sample of all 76 Cepheids brighter than V = 8 to create a list of all 18 Cepheids with companions more massive than 2.0 M ☉ . Orbital periods of many of these binaries are available from radial-velocity studies, or can be estimated for longer-period systems from detected velocity variability. In an imaging survey with the Hubble Space Telescope Wide Field Camera 3, we resolved three of the companions (those of η Aql, S Nor, and V659 Cen), allowing us to make estimates of the periods out to the long-period end of the distribution. Combining these separations with orbital data in the literature, we derive an unbiased distribution of binary separations, orbital periods, and mass ratios. The distribution of orbital periods shows that the 5 M ☉ binaries have systematically shorter periods than do 1 M ☉ stars. Our data also suggest that the distribution of mass ratios depends on both binary separation and system multiplicity. The distribution of mass ratios as a function of orbital separation, however, does not depend on whether a system is a binary or a triple

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.

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

International normalized ratio stability in warfarin-experienced patients with nonvalvular atrial fibrillation.

Science.gov (United States)

Nelson, Winnie W; Desai, Sunita; Damaraju, Chandrasekharrao V; Lu, Lang; Fields, Larry E; Wildgoose, Peter; Schein, Jeffery R

2015-06-01

Maintaining stable levels of anticoagulation using warfarin therapy is challenging. Few studies have examined the stability of the international normalized ratio (INR) in patients with nonvalvular atrial fibrillation (NVAF) who have had ≥6 months' exposure to warfarin anticoagulation for stroke prevention. Our objective was to describe INR control in NVAF patients who had been receiving warfarin for at least 6 months. Using retrospective patient data from the CoagClinic™ database, we analyzed data from NVAF patients treated with warfarin to assess the quality of INR control and possible predictors of poor INR control. Time within, above, and below the recommended INR range (2.0-3.0) was calculated for patients who had received warfarin for ≥6 months and had three or more INR values. The analysis also assessed INR patterns and resource utilization of patients with an INR >4.0. Logistic regression models were used to determine factors associated with poor INR control. Patients (n = 9433) had an average of 1.6 measurements per 30 days. Mean follow-up time was 544 days. Approximately 39% of INR values were out of range, with 23% of INR values being 3.0. Mean percent time with INR in therapeutic range was 67%; INR 3.0 was 14%. Patients with more than one reading of INR >4.0 (~39%) required an average of one more visit and took 3 weeks to return to an in-range INR. Male sex and age >75 years were predictive of better INR control, whereas a history of heart failure or diabetes were predictive of out-of-range INR values. However, patient characteristics did not predict the likelihood of INR >4.0. Out-of-range INR values remain frequent in patients with NVAF treated with warfarin. Exposure to high INR values was common, resulting in increased resource utilization.

Higher Levels of Albuminuria within the Normal Range Predict Incident Hypertension

OpenAIRE

Forman, John P.; Fisher, Naomi D.L.; Schopick, Emily L.; Curhan, Gary C.

2008-01-01

Higher levels of albumin excretion within the normal range are associated with cardiovascular disease in high-risk individuals. Whether incremental increases in urinary albumin excretion, even within the normal range, are associated with the development of hypertension in low-risk individuals is unknown. This study included 1065 postmenopausal women from the first Nurses’ Health Study and 1114 premenopausal women from the second Nurses’ Health Study who had an albumin/creatinine ratio

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.

Characteristics of plant concentration ratios assessed in a 64-site field survey of 23 elements

International Nuclear Information System (INIS)

Sheppard, S.C.; Evenden, W.G.

1990-01-01

Many of the statistical characteristics of plant concentration ratios (CRs) and translocation factors (TFs) have not been critically assessed, especially in field surveys. The statistical characteristics, particularly the measures of variation, are important for stochastic modelling of plant uptake. The CR and TF values for 23 naturally occurring elements throughout the geographic range of one plant species, blueberries (Vaccinium angustifolium), in Canada were surveyed. Although the ratios imply linear relationships, the numerator concentrations were not closely correlated with the denominator concentrations. The variation in the ratios was not clearly related to the means or to characteristics of the elements. The overall geometric standard deviation for CRs was 2.5 and for TFs was 1.6. The values of CR were intercorrelated for certain groups of elements and these groups reflected the periodic classification of elements. Thus, correlation between elements in stochastic models, which may reduce overall variability, is valid. Site variables such as soil pH, soil bulk density, soil fertility and plant growth condition were only slightly useful in statistically explaining some of the variation in CR values. (author)

High Dynamic Range Imaging Using Multiple Exposures

Science.gov (United States)

Hou, Xinglin; Luo, Haibo; Zhou, Peipei; Zhou, Wei

2017-06-01

It is challenging to capture a high-dynamic range (HDR) scene using a low-dynamic range (LDR) camera. This paper presents an approach for improving the dynamic range of cameras by using multiple exposure images of same scene taken under different exposure times. First, the camera response function (CRF) is recovered by solving a high-order polynomial in which only the ratios of the exposures are used. Then, the HDR radiance image is reconstructed by weighted summation of the each radiance maps. After that, a novel local tone mapping (TM) operator is proposed for the display of the HDR radiance image. By solving the high-order polynomial, the CRF can be recovered quickly and easily. Taken the local image feature and characteristic of histogram statics into consideration, the proposed TM operator could preserve the local details efficiently. Experimental result demonstrates the effectiveness of our method. By comparison, the method outperforms other methods in terms of imaging quality.

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.

Spatial Cognition and Range Use in Free-Range Laying Hens.

Science.gov (United States)

Campbell, Dana L M; Talk, Andrew C; Loh, Ziyang A; Dyall, Tim R; Lee, Caroline

2018-02-08

Radio-frequency identification tracking shows individual free-range laying hens vary in range use, with some never going outdoors. The range is typically more environmentally complex, requiring navigation to return to the indoor resources. Outdoor-preferring hens may have improved spatial abilities compared to indoor-preferring hens. Experiment 1 tested 32 adult ISA Brown hens in a T-maze learning task that showed exclusively-indoor birds were slowest to reach the learning success criterion ( p 0.05), the age that coincided with the onset of lay. Enriched birds that were faster to learn the maze task showed more range visits in the first 4 weeks of range access. Enriched and non-enriched birds showed no differences in telencephalon or hippocampal volume ( p > 0.05). Fear may reduce spatial abilities but further testing with more pen replicates per early rearing treatments would improve our understanding of the relationship between spatial cognitive abilities and range use.

Urinary pregnandiol-3-glucuronide and estrone conjugates to creatinine ratios in early pregnancies complicated by vaginal bleeding.

Science.gov (United States)

Davidson, B J

1986-10-01

There is no simple and rapid test available to predict the outcome of an early pregnancy complicated by vaginal bleeding. In this prospective study, 15 women with normal pregnancies collected a weekly urine sample between 6 and 13 weeks' gestation. A single random urine sample was obtained from 15 women with bleeding who continued to carry their child and 50 women who proceeded to have a spontaneous abortion (SAB). Pregnandiol-3-glucuronide (PDG) was determined with the use of enzyme-multiplied immunoassay technique (EMIT) and estrone conjugates (E1C) were measured by radioimmunoassay (RIA). The ratios of these metabolites to creatinine (C) were calculated. PDG/C ratios in normal women rose gradually from 6 weeks on. All women with bleeding during a normal pregnancy had ratios in the normal range, but 94% of women with a SAB had ratios below the normal range. The E1C/C ratio remained unchanged from 6 to 11 weeks and then rose rapidly. Until 11 weeks, there was no clear separation between the E1C/C ratios of the women with a SAB and the women with bleeding who continued their pregnancies. The prognosis of threatened abortion can be made by a urinary PDG/C ratio but not by an E1C/C ratio. EMIT is simple and quick and uses technology present in many laboratories.

Back work ratio of Brayton cycle; La relacion de trabajo de retroceso de un ciclo Brayton

Energy Technology Data Exchange (ETDEWEB)

Malaver de la Fuente, M. [Universidad Maritima del Caribe (Venezuela)]. E-mail: mmf_umc@hotmail.com

2010-07-15

This paper analyzes the existing relation between temperatures, back work ratio and net work of Brayton cycle, a cycle that describes gas turbine engines performance. The application of computational software helps to show the influence of back work ratio or coupling ratio, compressor and turbine inlet temperatures in an ideal thermodynamical cycle. The results lead to deduce that the maximum value reached in back work ratio will depend on the ranges of maximum and minimal temperatures of Brayton cycle. [Spanish] En este articulo se estudia la relacion que existe entre las temperaturas, la relacion de trabajo de retroceso y el trabajo neto en el ciclo Brayton, que es el ciclo ideal que describe el comportamiento de los motores de turbina de gas. La aplicacion de programas computarizados ayuda a mostrar la influencia de la relacion de trabajo de retroceso o relacion de acoplamiento, la temperatura de entrada al compresor y la temperatura de entrada a la turbina en este ciclo termodinamico ideal. Los resultados obtenidos permiten deducir que el valor maximo que alcanza la relacion de trabajo de retroceso dependera de los limites de temperatura maxima y minima impuestos en el ciclo Brayton.

Periodic TiO2 Nanostructures with Improved Aspect and Line/Space Ratio Realized by Colloidal Photolithography Technique

Directory of Open Access Journals (Sweden)

Loïc Berthod

2017-10-01

Full Text Available This paper presents substantial improvements of the colloidal photolithography technique (also called microsphere lithography with the goal of better controlling the geometry of the fabricated nano-scale structures—in this case, hexagonally arranged nanopillars—printed in a layer of directly photopatternable sol-gel TiO2. Firstly, to increase the achievable structure height the photosensitive layer underneath the microspheres is deposited on a reflective layer instead of the usual transparent substrate. Secondly, an increased width of the pillars is achieved by tilting the incident wave and using multiple exposures or substrate rotation, additionally allowing to better control the shape of the pillar’s cross section. The theoretical analysis is carried out by rigorous modelling of the photonics nanojet underneath the microspheres and by optimizing the experimental conditions. Aspect ratios (structure height/lateral structure size greater than 2 are predicted and demonstrated experimentally for structure dimensions in the sub micrometer range, as well as line/space ratios (lateral pillar size/distance between pillars greater than 1. These nanostructures could lead for example to materials exhibiting efficient light trapping in the visible and near-infrared range, as well as improved hydrophobic or photocatalytic properties for numerous applications in environmental and photovoltaic systems.

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

Science.gov (United States)

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

2018-03-01

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

Comparison of the CoaguChek XS handheld coagulation analyzer and conventional laboratory methods measuring international normalised ratio (INR) values during the time to therapeutic range after mechanical valve surgery.

Science.gov (United States)

Bardakci, Hasmet; Altıntaş, Garip; Çiçek, Omer Faruk; Kervan, Umit; Yilmaz, Sevinc; Kaplan, Sadi; Birincioglu, Cemal Levent

2013-05-01

To compare the international normalised ratio (INR) value of patients evaluated using the CoaguChek XS versus conventional laboratory methods, in the period after open-heart surgery for mechanical valve replacement until a therapeutic range is achieved using vitamin K antagonists (VKA) together with low molecular weight heparin (LMWH). One hundred and five patients undergoing open-heart surgery for mechanical valve replacement were enrolled. Blood samples were collected from patients before surgery, and on the second and fifth postoperative days, simultaneously for both the point of care device and conventional laboratory techniques. Patients were administered VKA together with LMWH at therapeutic doses (enoxaparin 100 IU/kg twice daily) subcutaneously, until an effective range was achieved on approximately the fifth day after surgery. The mean INR values using the CoaguChek XS preoperatively and on the second and fifth days postoperatively were 1.20 (SD ± 0.09), 1.82 (SD ± 0.45), and 2.55 (SD ± 0.55), respectively. Corresponding results obtained using conventional laboratory techniques were 1.18 (SD ± 0.1), 1.81 (SD ± 0.43), and 2.51 (SD ± 0.58). The correlation coefficient was r = 0.77 preoperatively, r = 0.981 on postoperative day 2, and r = 0.983 on postoperative day 5. Results using the CoaguChek XS Handheld Coagulation Analyzer correlated strongly with conventional laboratory methods, in the bridging period between open-heart surgery for mechanical valve replacement and the achievement of a therapeutic range on warfarin and LMWH. © 2013 Wiley Periodicals, Inc.

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...

Estimating the sample mean and standard deviation from the sample size, median, range and/or interquartile range.

Science.gov (United States)

Wan, Xiang; Wang, Wenqian; Liu, Jiming; Tong, Tiejun

2014-12-19

In systematic reviews and meta-analysis, researchers often pool the results of the sample mean and standard deviation from a set of similar clinical trials. A number of the trials, however, reported the study using the median, the minimum and maximum values, and/or the first and third quartiles. Hence, in order to combine results, one may have to estimate the sample mean and standard deviation for such trials. In this paper, we propose to improve the existing literature in several directions. First, we show that the sample standard deviation estimation in Hozo et al.'s method (BMC Med Res Methodol 5:13, 2005) has some serious limitations and is always less satisfactory in practice. Inspired by this, we propose a new estimation method by incorporating the sample size. Second, we systematically study the sample mean and standard deviation estimation problem under several other interesting settings where the interquartile range is also available for the trials. We demonstrate the performance of the proposed methods through simulation studies for the three frequently encountered scenarios, respectively. For the first two scenarios, our method greatly improves existing methods and provides a nearly unbiased estimate of the true sample standard deviation for normal data and a slightly biased estimate for skewed data. For the third scenario, our method still performs very well for both normal data and skewed data. Furthermore, we compare the estimators of the sample mean and standard deviation under all three scenarios and present some suggestions on which scenario is preferred in real-world applications. In this paper, we discuss different approximation methods in the estimation of the sample mean and standard deviation and propose some new estimation methods to improve the existing literature. We conclude our work with a summary table (an Excel spread sheet including all formulas) that serves as a comprehensive guidance for performing meta-analysis in different

Haldane’s Rule Is Linked to Extraordinary Sex Ratios and Sperm Length in Stalk-Eyed Flies

Science.gov (United States)

Wilkinson, Gerald S.; Christianson, Sarah J.; Brand, Cara L.; Ru, George; Shell, Wyatt

2014-01-01

We use three allopatric populations of the stalk-eyed fly Teleopsis dalmanni from Southeast Asia to test two predictions made by the sex chromosome drive hypothesis for Haldane’s rule. The first is that modifiers that suppress or enhance drive should evolve rapidly and independently in isolated populations. The second is that drive loci or modifiers should also cause sterility in hybrid males. We tested these predictions by assaying the fertility of 2066 males derived from backcross experiments involving two pairs of populations and found that the proportion of mated males that fail to produce any offspring ranged from 38 to 60% among crosses with some males producing strongly female-biased or male-biased sex ratios. After genotyping each male at 25–28 genetic markers we found quantitative trait loci (QTL) that jointly influence male sterility, sperm length, and biased progeny sex ratios in each pair of populations, but almost no shared QTL between population crosses. We also discovered that the extant XSR chromosome has no effect on sex ratio or sterility in these backcross males. Whether shared QTL are caused by linkage or pleiotropy requires additional study. Nevertheless, these results indicate the presence of a “cryptic” drive system that is currently masked by suppressing elements that are associated with sterility and sperm length within but not between populations and, therefore, must have evolved since the populations became isolated, i.e., in hybrid sterility. PMID:25164880

Interannual Variations in Ecosystem Oxidative Ratio in Croplands, Deciduous Forest, Coniferous Forest, and Early Successional Forest Ecosystems

Science.gov (United States)

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

2009-12-01

Ecosystem net primary productivity (NPP) can vary significantly with annual variations in precipitation and temperature. These climate variations can also drive changes in plant carbon allocation patterns. Shifting allocation patterns can lead to variation in net ecosystem biochemical stocks (e.g. kg cellulose, lignin, protein, and lipid/ha), which can in turn lead to shifts in ecosystem oxidative ratio (OR). OR is the molar ratio of O2 released : CO2 fixed during biosynthesis. Major plant biochemicals vary substantially in oxidative ratio, ranging from average organic acid OR values of 0.75 to average lipid OR values of 1.37 (Masiello et al., 2008). OR is a basic property of ecosystem biochemistry, and is also an essential variable needed to constrain the size of the terrestrial biospheric carbon sink (Keeling et al., 1996). OR is commonly assumed to be 1.10 (e.g. Prentice et al., 2001), but small variations in net ecosystem OR can drive large errors in estimates of the size of the terrestrial carbon sink (Randerson et al., 2006). We hypothesized that interannual changes in climate may drive interannual variation in ecosystem OR values. Working at Kellogg Biological Station NSF LTER, we measured the annual average OR of coniferous and deciduous forests, an early successional forest, and croplands under both corn and soy. There are clear distinctions between individual ecosystems (e.g., the soy crops have a higher OR than the corn crops, and the coniferous forests have a higher OR than the deciduous forests), but the ecosystems themselves retained remarkably constant annual OR values between 1998 and 2008.

Range walk error correction and modeling on Pseudo-random photon counting system

Science.gov (United States)

Shen, Shanshan; Chen, Qian; He, Weiji

2017-08-01

Signal to noise ratio and depth accuracy are modeled for the pseudo-random ranging system with two random processes. The theoretical results, developed herein, capture the effects of code length and signal energy fluctuation are shown to agree with Monte Carlo simulation measurements. First, the SNR is developed as a function of the code length. Using Geiger-mode avalanche photodiodes (GMAPDs), longer code length is proven to reduce the noise effect and improve SNR. Second, the Cramer-Rao lower bound on range accuracy is derived to justify that longer code length can bring better range accuracy. Combined with the SNR model and CRLB model, it is manifested that the range accuracy can be improved by increasing the code length to reduce the noise-induced error. Third, the Cramer-Rao lower bound on range accuracy is shown to converge to the previously published theories and introduce the Gauss range walk model to range accuracy. Experimental tests also converge to the presented boundary model in this paper. It has been proven that depth error caused by the fluctuation of the number of detected photon counts in the laser echo pulse leads to the depth drift of Time Point Spread Function (TPSF). Finally, numerical fitting function is used to determine the relationship between the depth error and the photon counting ratio. Depth error due to different echo energy is calibrated so that the corrected depth accuracy is improved to 1cm.

Clinical evaluation of free to total prostate specific antigen ratio in serum

International Nuclear Information System (INIS)

Cheng Wei; Deng Shouzhen; Lin Xiangtong

1999-01-01

Free and total prostate specific antigen (F-PSA and T-PSA) in serum were measured with immunoradiometric assay and the F/T-PSA ratio was calculated in 175 patients with T-PSA levels in the range of 4-20 μg/L. Among them 141 patients were benign prostatic hyperplasia (BPH), 23 were untreated prostate cancer (Pca untreated) and 11 were treated prostate cancer (Pca treated). The results showed that difference in F-PSA and F/T-PSA ratio for BPH group and Pca untreated group were statistically significant (P<0.01). The effectiveness of F/T-PSA ratio for Pca (89.9%) was higher than F-PSA (54.8%). The receiver-operating characteristic (ROC) curve showed an improved diagnostic efficacy of F/T-PSA ratio compared with T-PSA for discrimination between BPH and Pca. If mean F/T-PSA ratio value + 1 SE (13.2%) was used in BPH group as discrimination limits of Pca patients, the diagnostic accuracy of BPH group and Pca untreated group were 90.8% and 82.6% respectively. Thereby F/T-PSA ratio may be useful for the differentiation between BPH and prostate cancer

Properties of Wide-dose-range GafChromic Films for Synchrotron Radiation Facility

International Nuclear Information System (INIS)

Nariyama, Nobuteru

2007-01-01

GafChromic films have been used at SPring-8 to detect the intensively irradiated parts and protect them from damage by being covered with shield or moved. To extend the usable dose range more widely, a new type of sensitive film EBT was investigated for the introduction. Calibration curves were obtained irradiated with 60Co γ rays and compared with those of other GafChromic films. For the application, these films were set in the white x-ray hutch and the dose distribution was measured. Ratio of doses given by EBT and XT-R indicated the degree of the photon spectrum hardness, which depended on the positions. As a result, dose range from 50 mGy to 300 kGy became available for dose distribution measurements, and a set of films having different energy responses was found to give information of photon spectra

Efficient, Low Pressure Ratio Propulsor for Gas Turbine Engines

Science.gov (United States)

Gallagher, Edward J. (Inventor); Monzon, Byron R. (Inventor)

2018-01-01

A gas turbine engine includes a bypass flow passage that has an inlet and defines a bypass ratio in a range of approximately 8.5 to 13.5. A fan is arranged within the bypass flow passage. A first turbine is a 5-stage turbine and is coupled with a first shaft, which is coupled with the fan. A first compressor is coupled with the first shaft and is a 3-stage compressor. A second turbine is coupled with a second shaft and is a 2-stage turbine. The fan includes a row of fan blades that extend from a hub. The row includes a number (N) of the fan blades, a solidity value (R) at tips of the fab blades, and a ratio of N/R that is from 14 to 16.

Minimum critical power ratio control device for nuclear power plants

International Nuclear Information System (INIS)

Kurosawa, Tsuneo.

1991-01-01

Reactor core flowrate is determined by comparing a minimum critical power ratio calculated based on the status amount of a nuclear power plant and a control value for the minimum critical power ratio that depends on the reactor core flowrate. Further, the minimum critical power ratio and a control value for the minimum critical power ratio that depends on the reactor thermal power are compared to set a reactor thermal power converted to a reactor core flowrate. Deviation between the thus determined reactor core flowrate and the present reactor core flowrate is calculated. When the obtained deviation is lower than a rated value, a reactor core flowrate set signal is generated to a reactor flowrate control means, to control the reactor power by a recycling flowrate control system of the reactor. On the other hand, when the deviation exceeds the determined value, the reactor core flowrate set signal is converted into a reactor thermal power, to control the position of control rods and control the reactor power. Then, monitor and control can be conducted safely and automatically without depending on operator's individual ability over the entire operation range corresponding to load following operation. (N.H.)

Density-ratio effects on buoyancy-driven variable-density turbulent mixing

Science.gov (United States)

Aslangil, Denis; Livescu, Daniel; Banerjee, Arindam

2017-11-01

Density-ratio effects on the turbulent mixing of two incompressible, miscible fluids with different densities subject to constant acceleration are studied by means of high-resolution Direct Numerical Simulations. In a triply periodic domain, turbulence is generated by stirring in response to the differential buoyancy forces within the flow. Later, as the fluids become molecularly mixed, dissipation starts to overcome turbulence generation by bouyancy. Thus, the flow evolution includes both turbulence growth and decay, and it displays features present in the core region of the mixing layer of the Rayleigh-Taylor as well as Richtmyer-Meshkov instabilities. We extend the previous studies by investigating a broad range of density-ratio, from 1-14.4:1, corresponding to Atwood numbers of 0.05-0.87. Here, we focus on the Atwood number dependence of mixing-efficiency, that is defined based on the energy-conversion ratios from potential energy to total and turbulent kinetic energies, the decay characteristics of buoyancy-assisted variable-density homogeneous turbulence, and the effects of high density-ratios on the turbulence structure and mixing process. Authors acknowledge financial support from DOE-SSAA (DE-NA0003195) and NSF CAREER (#1453056) awards.

Measurement of the charge ratio of atmospheric muons with the CMS detector

Energy Technology Data Exchange (ETDEWEB)

Khachatryan, Vardan [Yerevan Physics Inst. (Armenia); et al.

2010-08-01

We present a measurement of the ratio of positive to negative muon fluxes from cosmic ray interactions in the atmosphere, using data collected by the CMS detector both at ground level and in the underground experimental cavern at the CERN LHC. Muons were detected in the momentum range from 5 GeV/c to 1 TeV/c. The surface flux ratio is measured to be 1.2766 \\pm 0.0032(stat.) \\pm 0.0032 (syst.), independent of the muon momentum, below 100 GeV/c. This is the most precise measurement to date. At higher momenta the data are consistent with an increase of the charge ratio, in agreement with cosmic ray shower models and compatible with previous measurements by deep-underground experiments.

Parameter estimation in astronomy through application of the likelihood ratio. [satellite data analysis techniques

Science.gov (United States)

Cash, W.

1979-01-01

Many problems in the experimental estimation of parameters for models can be solved through use of the likelihood ratio test. Applications of the likelihood ratio, with particular attention to photon counting experiments, are discussed. The procedures presented solve a greater range of problems than those currently in use, yet are no more difficult to apply. The procedures are proved analytically, and examples from current problems in astronomy are discussed.

GasBench/isotope ratio mass spectrometry: a carbon isotope approach to detect exogenous CO(2) in sparkling drinks.

Science.gov (United States)

Cabañero, Ana I; San-Hipólito, Tamar; Rupérez, Mercedes

2007-01-01

A new procedure for the determination of carbon dioxide (CO(2)) (13)C/(12)C isotope ratios, using direct injection into a GasBench/isotope ratio mass spectrometry (GasBench/IRMS) system, has been developed to improve isotopic methods devoted to the study of the authenticity of sparkling drinks. Thirty-nine commercial sparkling drink samples from various origins were analyzed. Values of delta(13)C(cava) ranged from -20.30 per thousand to -23.63 per thousand, when C3 sugar addition was performed for a second alcoholic fermentation. Values of delta(13)C(water) ranged from -5.59 per thousand to -6.87 per thousand in the case of naturally carbonated water or water fortified with gas from the spring, and delta(13)C(water) ranged from -29.36 per thousand to -42.09 per thousand when industrial CO(2) was added. It has been demonstrated that the addition of C4 sugar to semi-sparkling wine (aguja) and industrial CO(2) addition to sparkling wine (cava) or water can be detected. The new procedure has advantages over existing methods in terms of analysis time and sample treatment. In addition, it is the first isotopic method developed that allows (13)C/(12)C determination directly from a liquid sample without previous CO(2) extraction. No significant isotopic fractionation was observed nor any influence by secondary compounds present in the liquid phase. Copyright (c) 2007 John Wiley & Sons, Ltd.

Characterization and immobilization of engineered sialidases from Trypanosoma rangeli for transsialylation

Directory of Open Access Journals (Sweden)

Birgitte Zeuner

2017-04-01

Full Text Available A sialidase (EC 3.2.1.18; GH 33 from non-pathogenic Trypanosoma rangeli has been engineered with the aim of improving its transsialylation activity. Recently, two engineered variants containing 15 and 16 amino acid substitutions, respectively, were found to exhibit significantly improved transsialylation activity: both had a 14 times higher ratio between transsialylation and hydrolysis products compared to the first reported mutant TrSA5mut. In the current work, these two variants, Tr15 and Tr16, were characterized in terms of pH optimum, thermal stability, effect of acceptor-to-donor ratio, and acceptor specificity for transsialylation using casein glycomacropeptide (CGMP as sialyl donor and lactose or other human milk oligosaccharide core structures as acceptors. Both sialidase variants exhibited pH optima around pH 4.8. Thermal stability of each enzyme was comparable to that of previously developed T. rangeli sialidase variants and higher than that of the native transsialidase from T. cruzi (TcTS. As for other engineered T. rangeli sialidase variants and TcTS, the acceptor specificity was broad: lactose, galactooligosaccharides (GOS, xylooligosaccharides (XOS, and human milk oligosaccharide structures lacto-N-tetraose (LNT, lacto-N-fucopentaose (LNFP V, and lacto-N-neofucopentaose V (LNnFP V were all sialylated by Tr15 and Tr16. An increase in acceptor-to-donor ratio from 2 to 10 had a positive effect on transsialylation. Both enzymes showed high preference for formation α(2,3-linkages at the non-reducing end of lactose in the transsialylation. Tr15 was the most efficient enzyme in terms of transsialylation reaction rates and yield of 3’-sialyllactose. Finally, Tr15 was immobilized covalently on glyoxyl-functionalized silica, leading to a 1.5-fold increase in biocatalytic productivity (mg 3’-sialyllactose per mg enzyme compared to free enzyme after 6 cycles of reuse. The use of glyoxyl-functionalized silica proved to be markedly better

Changes in monoterpene mixing ratios during summer storms in rural New Hampshire (USA)

Science.gov (United States)

Haase, K.B.; Jordan, C.; Mentis, E.; Cottrell, L.; Mayne, H.R.; Talbot, R.; Sive, B.C.

2011-01-01

Monoterpenes are an important class of biogenic hydrocarbons that influence ambient air quality and are a principle source of secondary organic aerosol (SOA). Emitted from vegetation, monoterpenes are a product of photosynthesis and act as a response to a variety of environmental factors. Most parameterizations of monoterpene emissions are based on clear weather models that do not take into account episodic conditions that can drastically change production and release rates into the atmosphere. Here, the ongoing monoterpene dataset from the rural Thompson Farm measurement site in Durham, New Hampshire is examined in the context of a set of known severe storm events. While some storm systems had a negligible influence on ambient monoterpene mixing ratios, the average storm event increased mixing ratios by 0.59 ?? 0.21 ppbv, a factor of 93 % above pre-storm levels. In some events, mixing ratios reached the 10's of ppbv range and persisted overnight. These mixing ratios correspond to increases in the monoterpene emission rate, ranging from 120 to 1240 g km-2 h -1 compared to an estimated clear weather rate of 116 to 193 g km-2 h-1. Considering the regularity of storm events over most forested areas, this could be an important factor to consider when modeling global monoterpene emissions and their resulting influence on the formation of organic aerosols. ?? 2011 Author(s).

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.

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.

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).

The mechanisms associated with the development of hypertension after exposure to lead, mercury species or their mixtures differs with the metal and the mixture ratio.

Science.gov (United States)

Wildemann, Tanja M; Siciliano, Steven D; Weber, Lynn P

2016-01-02

Hypertension is considered to be the most important risk factor for the development of cardiovascular diseases. Beside life-style risk factors, exposure to lead and mercury species are increasingly discussed as potential risk factors. Although there are a few previous studies, the underlying mechanism by which exposure to lead and mercury disturb blood pressure regulation is not currently understood. Potential mechanisms are oxidative stress production, kidney damage and activation of the renin-angiotensin system (RAS), all of which can interact to cause dysregulation of blood pressure. Male rats (Wistar) were exposed to lead, inorganic mercury, methylmercury or two mixtures of all three metals for four weeks through the drinking water. The two mixture ratios were based on ratios of known reference values or environmental exposure from the literature. To investigate the potential mechanism of actions, blood pressure was measured after four weeks and compared to plasma nitrotyrosine or reduced/oxidized glutathione levels in liver as markers for oxidative stress. Plasma renin and angiotensin II levels were used as markers for RAS activation. Finally, kidney function and injury were assessed via urinary and plasma creatinine levels, creatinine clearance and urinary kidney-injury molecule (KIM-1). While exposure to lead by itself increased oxidative stress and kidney damage along with blood pressure, inorganic mercury did not affect blood pressure or any end-point examined. Conversely, methylmercury instead increased RAS activation along with blood pressure. Surprisingly, when administered as mixtures, lead no longer increased oxidative stress or altered kidney function. Moreover, the mixture based on an environmental ratio no longer had an effect on blood pressure, while the reference value ratio still retained an increase in blood pressure. Based on our results, the prominent mechanism of action associated with the development of hypertension seems to be oxidative

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.

Temporal variation of erythemally effective UVB/UVA ratio at Chilton, UK

International Nuclear Information System (INIS)

Hooke, R. J.; Pearson, A. J.; O'Hagan, J. B.

2012-01-01

An analysis of the temporal variation in the erythemally weighted UVB/UVA irradiance ratio using spectral data collected from a monitoring site in Chilton, UK (51 deg. N) for the 5-y period from 2004 to 2008 is presented. The variation in the diurnal ratio was found to be bell-shaped, with minima on average 1 h after sunrise and before sunset. The minima were found to be indicative of the point at which UVB becomes undetectable by the spectro-radiometer and therefore the outer boundary of useful data. A potential flaw entailed in the erythemal weighting of low-level spectral UV data is described. The peak daily ratio value was found to have a bell-shaped distribution over the course of a year with a maximum in July rather than at the summer solstice-a result explained by the ozone cycle. The peak daily ratio was found to vary by a factor of 4 over the course of the year; this range of variation was also found to occur over a single day in the summer. (authors)

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.

Effect of Processing Delay and Storage Conditions on Urine Albumin-to-Creatinine Ratio

Science.gov (United States)

Illingworth, Nicola; Staplin, Natalie; Kumar, Aishwarya; Storey, Ben; Hrusecka, Renata; Judge, Parminder; Mahmood, Maria; Parish, Sarah; Landray, Martin; Haynes, Richard; Baigent, Colin; Hill, Michael; Clark, Sarah

2016-01-01

Background and objectives Because there is substantial biologic intraindividual variation in albumin excretion, randomized trials of albuminuria-reducing therapies may need multiple urine samples to estimate daily urinary albumin excretion. Mailing spot urine samples could offer a convenient and cost-effective method to collect multiple samples, but urine albumin-to-creatinine ratio stability in samples stored at ambient temperatures for several days is unknown. Design, setting, participants, & measurements Patients with kidney disease provided fresh urine samples in two tubes (with and without boric acid preservative). Reference aliquots from each participant were analyzed immediately, whereas remaining aliquots were subject to different handling/storage conditions before analysis, including delayed processing for up to 7 days at three different storage temperatures (4°C, 18°C, and 30°C), multiple freeze-thaw cycles, and long–term frozen storage at −80°C, −40°C, and −20°C. We calculated the mean percentage change in urine albumin-to-creatinine ratio for each condition, and we considered samples stable if the 95% confidence interval was within a ±5% threshold. Results Ninety-three patients provided samples with detectable albuminuria in the reference aliquot. Median (interquartile range) urine albumin-to-creatinine ratio was 87 (20–499) mg/g. The inclusion of preservative had minimal effect on fresh urine albumin-to-creatinine ratio measurements but reduced the changes in albumin and creatinine in samples subject to processing delay and storage conditions. The urine albumin-to-creatinine ratio was stable for 7 days in samples containing preservative at 4°C and 18°C and 2 days when stored at 30°C. It was also stable in samples with preservative after three freeze-thaw cycles and in frozen storage for 6 months at −80°C or −40°C but not at −20°C. Conclusions Mailed urine samples collected with preservative and received within 7 days if

Effect of production system (barn and free range) and slaughter age on some production traits of guinea fowl.

Science.gov (United States)

Yamak, U S; Sarica, M; Boz, M A; Ucar, A

2018-01-01

A total of 200 guinea fowl was reared in either barn or free-range systems and slaughtered at 14, 16, or 18 wk of age in order to determine the effects of production system on live weight, feed consumption, and some carcass and slaughter traits. Production system had a significant effect on live weight until 14 wk of age. Live weights were similar between free-range and indoor production systems at 16 (1,150 g vs. 1,152 g) and 18 (1,196 g vs. 1,203 g) wk of age. Guinea fowl reared in a free-range system consumed more feed (7,693 g vs. 6,983 g), and guinea fowl reared in a barn had better feed conversion ratio (5.80 vs. 6.43) (P free-range system had significantly less abdominal fat (P < 0.05). © 2017 Poultry Science Association Inc.

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.

Isotope ratios of 240Pu/239Pu in soil samples from different areas

International Nuclear Information System (INIS)

Muramatsu, Yasuyuki; Yoshida, Satoshi; Yamazaki, Shinnosuke

2003-01-01

Plutonium concentrations and 240 Pu/ 239 Pu atom ratios in soil samples from Japan and other areas in the world (including IAEA standard reference materials) were determined by ICP-MS. The range of 240 Pu/ 239 Pu atom ratios observed in 21 Japanese soil samples was 0.155 - 0.194 and the average was 0.180 ± 0.011, which is comparable to the global fallout value. A low ratio of about 0.05, which is derived from Pu-bomb, was found in samples from Nishiyama (Nagasaki) and Mururoa Atoll (IAEA-368), while a high ratio of about 0.31 was found in a sample from Bikini Atoll (Marshall Islands). The ratio for Irish Sea sediment (IAEA-135) was 0.21, which was higher than the global fallout value, suggesting the influence by the contamination from the Sellafield facility. The 240 Pu/ 239 Pu atom ratios in soils from the Chernobyl area were determined, and the ratio was found to be very high (about 0.4), indicating the high burn-up grade of the reactor fuel. These results show that the 240 Pu/ 239 Pu ratio can be used as a finger print to identify the source of the contamination. (author)

Photofission cross-section ratio measurement of 235U/238U using monoenergetic photons in the energy range of 9.0-16.6 MeV

Science.gov (United States)

Krishichayan; Bhike, Megha; Finch, S. W.; Howell, C. R.; Tonchev, A. P.; Tornow, W.

2017-05-01

Photofission cross-section ratios of 235U and 238U have been measured using monoenergetic photon beams at the HIγS facility of TUNL. These measurements have been performed in small energy steps between 9.0 and 16.6 MeV using a dual-fission ionization chamber. Measured cross-section ratios are compared with the previous experimental data as well as with the recent evaluated nuclear data library ENDF.

Digit ratio (2D:4D) and circulating testosterone, oestradiol, and progesterone levels across the menstrual cycle.

Science.gov (United States)

Richards, Gareth; Klimek, Magdalena; Jasienska, Grazyna; Marcinkowska, Urszula M

2018-02-01

Digit ratio (2D:4D) is used by researchers as an indicator of prenatal sex hormone exposure. Two previous studies have examined associations between 2D:4D and circulating sex steroid concentrations across the menstrual cycle in adult females. One reported that digit ratio correlated positively with oestradiol levels, whereas the other found no such effect; neither observed significant associations with progesterone. To examine associations between 2D:4D, as well as asymmetry (i.e. right minus left 2D:4D), and circulating sex steroids across the menstrual cycle. Correlational. 32 naturally cycling adult females from rural southern Poland. Salivary oestradiol, progesterone, testosterone, and testosterone to oestradiol ratio (T:O) measured during the follicular, peri-ovulatory, and luteal phases. Average levels across the cycle were also examined. Asymmetry in digit ratio correlated positively with oestradiol at each phase, as well as with average levels across the cycle. Each association, other than that relating to average levels, remained statistically significant after a range of covariates had been controlled for. No other significant correlations were observed between digit ratio variables and circulating hormone levels. Our results might suggest that low exposure to androgens and/or high exposure to oestrogens during gestation is a predictor of high oestradiol levels in naturally cycling females of reproductive age. However, considering that it was asymmetry in digit ratio, and not either right or left 2D:4D, that was a significant predictor, it is also possible that these effects reflect more general associations between bilateral asymmetry and circulating oestradiol levels. Copyright © 2017 Elsevier B.V. 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 ...

Characterization of diesel fuel by chemical separation combined with capillary gas chromatography (GC) isotope ratio mass spectrometry (IRMS).

Science.gov (United States)

Harvey, Scott D; Jarman, Kristin H; Moran, James J; Sorensen, Christina M; Wright, Bob W

2012-09-15

The purpose of this study was to perform a preliminary investigation of compound-specific isotope analysis (CSIA) of diesel fuels to evaluate whether the technique could distinguish diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for discovering fuel tax evasion schemes or for environmental forensic studies. Two urea adduction-based techniques were used to isolate the n-alkanes from the fuel. Both carbon isotope ratio (δ(13)C) and hydrogen isotope ratio (δD) values for the n-alkanes were then determined by CSIA in each sample. The samples investigated had δ(13)C values that ranged from -30.1‰ to -26.8‰, whereas δD values ranged from -83‰ to -156‰. Plots of δD versus δ(13)C with sample n-alkane points connected in order of increasing carbon number gave well-separated clusters with characteristic shapes for each sample. Principal components analysis (PCA) with δ(13)C, δD, or combined δ(13)C and δD data was applied to extract the maximum information content. PCA scores plots could clearly differentiate the samples, thereby demonstrating the potential of this approach for distinguishing (e.g., fingerprinting) fuel samples using δ(13)C and δD values. Copyright © 2012 Elsevier B.V. All rights reserved.

Financial Key Ratios

OpenAIRE

Tănase Alin-Eliodor

2014-01-01

This article focuses on computing techniques starting from trial balance data regarding financial key ratios. There are presented activity, liquidity, solvency and profitability financial key ratios. It is presented a computing methodology in three steps based on a trial balance.

Broad Anatomical Variation within a Narrow Wood Density Range--A Study of Twig Wood across 69 Australian Angiosperms.

Science.gov (United States)

Ziemińska, Kasia; Westoby, Mark; Wright, Ian J

2015-01-01

Just as people with the same weight can have different body builds, woods with the same wood density can have different anatomies. Here, our aim was to assess the magnitude of anatomical variation within a restricted range of wood density and explore its potential ecological implications. Twig wood of 69 angiosperm tree and shrub species was analyzed. Species were selected so that wood density varied within a relatively narrow range (0.38-0.62 g cm-3). Anatomical traits quantified included wood tissue fractions (fibres, axial parenchyma, ray parenchyma, vessels, and conduits with maximum lumen diameter below 15 μm), vessel properties, and pith area. To search for potential ecological correlates of anatomical variation the species were sampled across rainfall and temperature contrasts, and several other ecologically-relevant traits were measured (plant height, leaf area to sapwood area ratio, and modulus of elasticity). Despite the limited range in wood density, substantial anatomical variation was observed. Total parenchyma fraction varied from 0.12 to 0.66 and fibre fraction from 0.20 to 0.74, and these two traits were strongly inversely correlated (r = -0.86, P area to sapwood area ratio, and modulus of elasticity (0.24 ≤|r|≤ 0.41, P area to sapwood area ratio (0.47 ≤|r|≤ 0.65, all P area spectrum. The fibre-parenchyma spectrum does not yet have any clear or convincing ecological interpretation.

Variations in the stable isotope ratios of specific aromatic and aliphatic hydrocarbons from coal conversion processes

Energy Technology Data Exchange (ETDEWEB)

McRae, C.; Snape, C.E.; Fallick, A.E. [University of Strathclyde, Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry

1998-07-01

To establish the scope for applying gas chromatography-isotope ratio mass spectrometry ({sup {delta}-13}C GC-IRMS) to molecular recognition problems in coal utilisation, {sup 13}C/{sup 12}C isotope ratios were determined for n-alkanes and polycyclic aromatic hydrocarbons (PAHs) as a function of coal rank and process conditions. Six coals ranging from a lignite to a low volatile bituminous coal were subjected to chloroform extraction, fixed-bed pyrolysis under hydrogen pressure (hydropyrolysis) and fluidised-bed (flash) pyrolysis. No significant variations in the stable isotope ratios of n-alkanes were evident as a function of either rank or conversion regime. In contrast, the isotope ratios of PAHs show large variations with those for hydropyrolysis (-23 to -25 parts per thousand) being similar to the bulk values of the initial coals and being isotopically heavier (less negative) than their fluidised-bed pyrolysis counterparts by 2-3 parts per thousand. However, the PAHs from fluidised-bed pyrolysis, which resemble closely those obtained from high temperature coal carbonization, are still heavier (by 2-3 parts per thousand) than those from diesel particulates and coal gasification and combustion residues. This provides a firm basis for the source apportionment of airborne PAHs in the proximity of coking plants, particularly with no major variations in the PAH isotope ratios being found as a function of rank.

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

A study about critical flow characteristics and the pipeline network modeling of a pressure regulator (II) : the influence of a opening ratio

International Nuclear Information System (INIS)

Shin, Chang Hoon; Ha, Jong Man; Lee, Cheol Gu; Her, Jae Young; Im, Ji Hyun; Joo, Won Gu

2005-01-01

The suitable pressure regulator modeling at each opening ratio and pressure ratio is very important to obtain reliable results, especially in small scale pipeline network analysis such as a pressure regulator system. And it is needed to confirm both whether temperature recovery is achieved after passing by the pressure regulator's narrow neck and how much amount of low temperature area that can cause condensate accumulation is distributed by various PCV models and driving conditions. In this research, the numerical model resembling P company pressure regulator that is used widely for high pressure range in commercial, is adopted as the base model of CFD analysis to investigate pressure regulator's flow characteristics at each pressure ratio and opening ratio. And it is also introduced to examine pressure regulator's critical flow characteristics and possibility of condensation or freezing at each pressure ratio and opening ratio. Additionally, the comparison between the results of CFD analysis and the results of analytic solution obtained by compressible fluid-dynamics theory is attempted to validate the results of CFD modeling in this study and to estimate the accuracy of theoretical approach at each pressure ratio and opening ratio too

No Evidence for a Relationship Between Hair Testosterone Concentrations and 2D:4D Ratio or Risk Taking

Directory of Open Access Journals (Sweden)

Richard Ronay

2018-03-01

Full Text Available Using a recently developed alternative assay procedure to measure hormone levels from hair samples, we examined the relationships between testosterone, cortisol, 2D:4D ratio, overconfidence and risk taking. A total of 162 (53 male participants provided a 3 cm sample of hair, a scanned image of their right and left hands from which we determined 2D:4D ratios, and completed measures of overconfidence and behavioral risk taking. While our sample size for males was less than ideal, our results revealed no evidence for a relationship between hair testosterone concentrations, 2D:4D ratios and risk taking. No relationships with overconfidence emerged. Partially consistent with the Dual Hormone Hypothesis, we did find evidence for the interacting effect of testosterone and cortisol on risk taking but only in men. Hair testosterone concentrations were positively related to risk taking when levels of hair cortisol concentrations were low, in men. Our results lend support to the suggestion that endogenous testosterone and 2D:4D ratio are unrelated and might then exert diverging activating vs. organizing effects on behavior. Comparing our results to those reported in the existing literature we speculate that behavioral correlates of testosterone such as direct effects on risk taking may be more sensitive to state-based fluctuations than baseline levels of testosterone.

Hummingbird wing efficacy depends on aspect ratio and compares with helicopter rotors

NARCIS (Netherlands)

Kruyt, J.W.; Quicazan Rubio, E.M.; Heijst, van G.J.F.; Altshuler, D.L.; Lentink, D.

2014-01-01

Hummingbirds are the only birds that can sustain hovering. This unique flight behaviour comes, however, at high energetic cost. Based on helicopter and aeroplane design theory, we expect that hummingbird wing aspect ratio (AR), which ranges from about 3.0 to 4.5, determines aerodynamic efficacy.

Binary Cepheids: Separations and Mass Ratios in 5 M ⊙ Binaries

Science.gov (United States)

Evans, Nancy Evans; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.; Karovska, Margarita; Tingle, Evan

2013-10-01

Deriving the distribution of binary parameters for a particular class of stars over the full range of orbital separations usually requires the combination of results from many different observing techniques (radial velocities, interferometry, astrometry, photometry, direct imaging), each with selection biases. However, Cepheids—cool, evolved stars of ~5 M ⊙—are a special case because ultraviolet (UV) spectra will immediately reveal any companion star hotter than early type A, regardless of the orbital separation. We have used International Ultraviolet Explorer UV spectra of a complete sample of all 76 Cepheids brighter than V = 8 to create a list of all 18 Cepheids with companions more massive than 2.0 M ⊙. Orbital periods of many of these binaries are available from radial-velocity studies, or can be estimated for longer-period systems from detected velocity variability. In an imaging survey with the Hubble Space Telescope Wide Field Camera 3, we resolved three of the companions (those of η Aql, S Nor, and V659 Cen), allowing us to make estimates of the periods out to the long-period end of the distribution. Combining these separations with orbital data in the literature, we derive an unbiased distribution of binary separations, orbital periods, and mass ratios. The distribution of orbital periods shows that the 5 M ⊙ binaries have systematically shorter periods than do 1 M ⊙ stars. Our data also suggest that the distribution of mass ratios depends on both binary separation and system multiplicity. The distribution of mass ratios as a function of orbital separation, however, does not depend on whether a system is a binary or a triple. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained by the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.

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...

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.

Determination of thorium in the range of low concentrations

International Nuclear Information System (INIS)

Hill, R.; Lieser, K.H.

1992-01-01

Methods for the determination of Th in the range of low concentrations are compiled and discussed. Application of spectrophotometry and voltammetry is investigated. Spectrophotometry is applicable down to concentrations of the order of 0.1 μg/l as long as the ratio U:Th is low. Voltammetric determination of Th is not possible in the presence of Al. (orig.)

DPOAE generation dependence on primary frequencies ratio

Science.gov (United States)

Botti, Teresa; Sisto, Renata; Moleti, Arturo; D'Amato, Luisa; Sanjust, Filippo

2015-12-01

Two different mechanisms are responsible for the DPOAE generation. The nonlinear distortion wave-fixed mechanism generates the DPOAE Zero-Latency (ZL) component, as a backward traveling wave from the "overlap" region. Linear reflection of the forward DP wave (IDP) generates the DPOAE Long-Latency (LL) component through a place-fixed mechanism. ZL and LL components add up vectorially to generate the DPOAE recorded in the ear canal. The 2f1 - f2 and 2f2 - f1 DPOAE intensity depends on the stimulus level and on the primary frequency ratio r = f2/f1, where f1 and f2 are the primary stimuli frequencies. Here we study the behavior of the ZL and LL DPOAE components as a function of r by both numerical and laboratory experiments, measuring DPAOEs with an equal primary levels (L1 = L2) paradigm in the range [35, 75] dB SPL, with r ranging in [1.1, 1.45]. Numerical simulations of a nonlocal nonlinear model have been performed without cochlear roughness, to suppress the linear reflection mechanism. In this way the model solution at the base represents the DPOAE ZL component, and the solution at the corresponding DPOAE tonotopic place corresponds to the IDP. This technique has been not effectual to study the 2f2 - f1 DPOAE, as a consequence of its generation mechanism. While the 2f1 - f2 generation place is known to be the tonotopic place x(f2), the 2f2 - f1 DPOAE one has to be assumed basal to its corresponding reflection place. That is because ZL components generated in x(f2) cannot significantly pass through their resonant place. Moreover increasing the ratio r, 2f2 - f1 ZL and LL generation place approach each other, because the overlap region of primary tones decreases. Consequently, the distinction between the two places becomes complicated. DPOAEs have been measured in six young normal-hearing subjects. DPOAE ZL and LL components have been separated by a time-frequency filtering method based on the wavelet transform 1. due to their different phase gradient delay

Formation of high aspect ratio polyamide-6 nanofibers via electrically induced double layer during electrospinning

International Nuclear Information System (INIS)

Nirmala, R.; Nam, Ki Taek; Park, Soo-Jin; Shin, Yu-Shik; Navamathavan, R.; Kim, Hak Yong

2010-01-01

In the present study, the formation of high aspect ratio nanofibers in polyamide-6 was investigated as a function of applied voltage ranging from 15 to 25 kV using electrospinning technique. All other experimental parameters were kept constant. The electrospun polyamide-6 nanofibers were characterized by field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF). FE-SEM images of polyamide-6 nanofibers showed that the diameter of the electrospun fiber was decreased with increasing applied voltage. At the critical applied voltage, the polymer solution was completely ionized to form the dense high aspect ratio nanofibers in between the main nanofibers. The diameter of the polyamide-6 nanofibers was observed to be in the range of 75-110 nm, whereas the high aspect ratio structures consisted of regularly distributed very fine nanofibers with diameters of about 9-28 nm. Trends in fiber diameter and diameter distribution were discussed for the high aspect ratio nanofibers. TEM results revealed that the formation of double layers in polyamide-6 nanofibers and then split-up into ultrafine fibers. The electrically induced double layer in combination with the polyelectrolytic nature of solution is proposed as the suitable mechanisms for the formation of high aspect ratio nanofibers in polyamide-6.

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.

Estimation of (n,f) Cross-Sections by Measuring Reaction Probability Ratios

Energy Technology Data Exchange (ETDEWEB)

Plettner, C; Ai, H; Beausang, C W; Bernstein, L A; Ahle, L; Amro, H; Babilon, M; Burke, J T; Caggiano, J A; Casten, R F; Church, J A; Cooper, J R; Crider, B; Gurdal, G; Heinz, A; McCutchan, E A; Moody, K; Punyon, J A; Qian, J; Ressler, J J; Schiller, A; Williams, E; Younes, W

2005-04-21

Neutron-induced reaction cross-sections on unstable nuclei are inherently difficult to measure due to target activity and the low intensity of neutron beams. In an alternative approach, named the 'surrogate' technique, one measures the decay probability of the same compound nucleus produced using a stable beam on a stable target to estimate the neutron-induced reaction cross-section. As an extension of the surrogate method, in this paper they introduce a new technique of measuring the fission probabilities of two different compound nuclei as a ratio, which has the advantage of removing most of the systematic uncertainties. This method was benchmarked in this report by measuring the probability of deuteron-induced fission events in coincidence with protons, and forming the ratio P({sup 236}U(d,pf))/P({sup 238}U(d,pf)), which serves as a surrogate for the known cross-section ratio of {sup 236}U(n,f)/{sup 238}U(n,f). IN addition, the P({sup 238}U(d,d{prime}f))/P({sup 236}U(d,d{prime}f)) ratio as a surrogate for the {sup 237}U(n,f)/{sup 235}U(n,f) cross-section ratio was measured for the first time in an unprecedented range of excitation energies.

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.

Aerodynamic Characteristics of a Flying-Boat Hull Having a Length-Beam Ratio of 15, TED No. NACA 2206

Science.gov (United States)

Riebe, John M.; Naeseth, Rodger L.

1951-01-01

An investigation was made in the Langley 300 MPH 7- by 10-foot tunnel to determine the aerodynamic characteristics of a flying-boat hull of a length-beam ratio of 15 in the presence of a wing. The investigation was an extension of previous tests made on hulls of length-beam ratios of 6, 9, and 12; these hulls were designed to have approximately the same hydrodynamic performance with respect to spray and resistance characteristics. Comparison with the previous investigation at lower length-beam ratios indicated a reduction in minimum drag coefficients of 0.0006 (10 peroent)with fixed transition when the length-beam ratio was extended from 12 to 15. As with the hulls of lower length-beam ratio, the drag reduction with a length-beam ratio of 15 occurred throughout the range of angle of attack tested and the angle of attack for minimum drag was in the range from 2deg to 3deg. Increasing the length-beam ratio from 12 to 15 reduced the hull longitudinal instability by an mount corresponding to an aerodynamic-center shift of about 1/2 percent of the mean aerodynamic chord of the hypothetical flying boat. At an angle of attack of 2deg, the value of the variation of yawing-moment coefficient with angle of yaw for a length-beam ratio of 15 was 0.00144, which was 0.00007 larger than the value for a length-beam ratio of 12.

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

Estimating the hemodynamic influence of variable main body-to-iliac limb length ratios in aortic endografts.

Science.gov (United States)

Georgakarakos, Efstratios; Xenakis, Antonios; Georgiadis, George S

2018-02-01

We conducted a computational study to assess the hemodynamic impact of variant main body-to-iliac limb length (L1/L2) ratios on certain hemodynamic parameters acting on the endograft (EG) either on the normal bifurcated (Bif) or the cross-limb (Cx) fashion. A customary bifurcated 3D model was computationally created and meshed using the commercially available ANSYS ICEM (Ansys Inc., Canonsburg, PA, USA) software. The total length of the EG, was kept constant, while the L1/L2 ratio ranged from 0.3 to 1.5 in the Bif and Cx reconstructed EG models. The compliance of the graft was modeled using a Fluid Structure Interaction method. Important hemodynamic parameters such as pressure drop along EG, wall shear stress (WSS) and helicity were calculated. The greatest pressure decrease across EG was calculated in the peak systolic phase. With increasing L1/L2 it was found that the Pressure Drop was increasing for the Cx configuration, while decreasing for the Bif. The greatest helicity (4.1 m/s2) was seen in peak systole of Cx with ratio of 1.5 whereas its greatest value (2 m/s2) was met in peak systole in the Bif with the shortest L1/L2 ratio (0.3). Similarly, the maximum WSS value was highest (2.74Pa) in the peak systole for the 1.5 L1/L2 of the Cx configuration, while the maximum WSS value equaled 2 Pa for all length ratios of the Bif modification (with the WSS found for L1/L2=0.3 being marginally higher). There was greater discrepancy in the WSS values for all L1/L2 ratios of the Cx bifurcation compared to Bif. Different L1/L2 rations are shown to have an impact on the pressure distribution along the entire EG while the length ratio predisposing to highest helicity or WSS values is also determined by the iliac limbs pattern of the EG. Since current custom-made EG solutions can reproduce variability in main-body/iliac limbs length ratios, further computational as well as clinical research is warranted to delineate and predict the hemodynamic and clinical effect of variable

Whole-Organism Concentration Ratios for Plutonium in Wildlife from Past US Nuclear Research Data

Energy Technology Data Exchange (ETDEWEB)

johansen, M.; Kamboj; Kuhne, W.

2012-07-26

Whole-organism concentration ratios (CR{sub wo-media}) for plutonium (Pu) in wildlife were calculated using data from the broad range of organism types and environmental settings of the US nuclear research program. Original sources included site-specific reports and scientific journal articles typically from 1960s to 80s research. Most of the calculated CR{sub wo-media} values are new to existing data sets, and, for some wildlife categories, serve to fill gaps or add to sparse data including those for terrestrial reptile; freshwater bird, crustacean and zooplankton; and marine crustacean and zooplankton. Ratios of Pu concentration in the whole-organism to that in specific tissues and organs are provided here for a range of freshwater and marine fish. The CR{sub wo-media} values in fish living in liquid discharge ponds were two orders of magnitude higher than those for similar species living in lakes receiving Pu from atmospheric fallout, suggesting the physico-chemical form of the source Pu can dominate over other factors related to transfer, such as organism size and feeding behavior. Small rodent data indicated one to two order of magnitude increases when carcass, pelt, and gastrointestinal tract were included together in the whole-organism calculation compared to that for carcass alone. Only 4% of Pu resided in the carcass of small rodents compared to 75% in the gastrointestinal tract and 21% in the pelt.

Whole-organism concentration ratios for plutonium in wildlife from past US nuclear research data

International Nuclear Information System (INIS)

Johansen, M.P.; Kamboj, S.; Kuhne, W.W.

2013-01-01

Whole-organism concentration ratios (CR wo-media ) for plutonium (Pu) in wildlife were calculated using data from the broad range of organism types and environmental settings of the US nuclear research program. Original sources included site-specific reports and scientific journal articles typically from 1960s to 80s research. Most of the calculated CR wo-media values are new to existing data sets, and, for some wildlife categories, serve to fill gaps or add to sparse data including those for terrestrial reptile; freshwater bird, crustacean and zooplankton; and marine crustacean and zooplankton. Ratios of Pu concentration in the whole-organism to that in specific tissues and organs are provided here for a range of freshwater and marine fish. The CR wo-media values in fish living in liquid discharge ponds were two orders of magnitude higher than those for similar species living in lakes receiving Pu from atmospheric fallout, suggesting the physico-chemical form of the source Pu can dominate over other factors related to transfer, such as organism size and feeding behavior. Small rodent data indicated one to two order of magnitude increases when carcass, pelt, and gastrointestinal tract were included together in the whole-organism calculation compared to that for carcass alone. Only 4% of Pu resided in the carcass of small rodents compared to 75% in the gastrointestinal tract and 21% in the pelt

BINARY CEPHEIDS: SEPARATIONS AND MASS RATIOS IN 5 M {sub ☉} BINARIES

Energy Technology Data Exchange (ETDEWEB)

Evans, Nancy Remage; Karovska, Margarita; Tingle, Evan [Smithsonian Astrophysical Observatory, MS 4, 60 Garden Street, Cambridge, MA 02138 (United States); Bond, Howard E. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Schaefer, Gail H. [The CHARA Array, Georgia State University, P.O. Box 3965, Atlanta, GA 30302-3965 (United States); Mason, Brian D., E-mail: nevans@cfa.harvard.edu, E-mail: heb11@psu.edu, E-mail: schaefer@chara-array.org [US Naval Observatory, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420 (United States)

2013-10-01

Deriving the distribution of binary parameters for a particular class of stars over the full range of orbital separations usually requires the combination of results from many different observing techniques (radial velocities, interferometry, astrometry, photometry, direct imaging), each with selection biases. However, Cepheids—cool, evolved stars of ∼5 M {sub ☉}—are a special case because ultraviolet (UV) spectra will immediately reveal any companion star hotter than early type A, regardless of the orbital separation. We have used International Ultraviolet Explorer UV spectra of a complete sample of all 76 Cepheids brighter than V = 8 to create a list of all 18 Cepheids with companions more massive than 2.0 M {sub ☉}. Orbital periods of many of these binaries are available from radial-velocity studies, or can be estimated for longer-period systems from detected velocity variability. In an imaging survey with the Hubble Space Telescope Wide Field Camera 3, we resolved three of the companions (those of η Aql, S Nor, and V659 Cen), allowing us to make estimates of the periods out to the long-period end of the distribution. Combining these separations with orbital data in the literature, we derive an unbiased distribution of binary separations, orbital periods, and mass ratios. The distribution of orbital periods shows that the 5 M {sub ☉} binaries have systematically shorter periods than do 1 M {sub ☉} stars. Our data also suggest that the distribution of mass ratios depends on both binary separation and system multiplicity. The distribution of mass ratios as a function of orbital separation, however, does not depend on whether a system is a binary or a triple.

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

Mechanical design, analysis and testing of a large-range compliant microgripper

Directory of Open Access Journals (Sweden)

Y. Liu

2016-04-01

Full Text Available This paper presents the mechanical design, analysis, fabrication, and testing procedures of a new large-range microgripper which is based on a flexible hinge structure. The uniqueness of the gripper is that the gripper arms not only provide large gripping range but also deliver approximately rectilinear movement as the displacement in nonworking direction is extremely small. The large gripping range is enabled by a mechanism design based on dual-stage flexure amplifier to magnify the stroke of piezoelectric actuator. The first-stage amplifier is a modified version of the Scott Russell (SR mechanism and the second-stage amplifier contains a parallel mechanism. The displacement amplification ratio of the modified SR mechanism in the gripper has been enlarged to 3.56 times of the conventional design. Analytical static models of the gripper mechanism are developed and validated through finite-element analysis (FEA simulation. Results show that the gripping range is over 720 µm with a resonant frequency of 70.7 Hz and negligible displacement in nonworking direction. The total amplification ratio of the input displacement is 16.13. Moreover, a prototype of the gripper is developed by using aluminium 7075 for experimental testing. Experimental results validate the analytical model and FEA simulation results. The proposed microgripper can be employed in various microassembly applications such as pick-and-place of optical fibre.

Low power very high frequency resonant converter with high step down ratio

DEFF Research Database (Denmark)

Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

2013-01-01

This paper presents the design of a resonant converter with a switching frequency in the very high frequency range (30-300MHz), a large step down ratio and low output power. This gives the designed converters specifications which are far from previous results. The class E inverter and rectifier...

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).

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

Changes in monoterpene mixing ratios during summer storms in rural New Hampshire (USA

Directory of Open Access Journals (Sweden)

K. B. Haase

2011-11-01

Full Text Available Monoterpenes are an important class of biogenic hydrocarbons that influence ambient air quality and are a principle source of secondary organic aerosol (SOA. Emitted from vegetation, monoterpenes are a product of photosynthesis and act as a response to a variety of environmental factors. Most parameterizations of monoterpene emissions are based on clear weather models that do not take into account episodic conditions that can drastically change production and release rates into the atmosphere. Here, the monoterpene dataset from the rural Thompson Farm measurement site in Durham, New Hampshire is examined in the context of a set of known severe storm events. While some storm systems had a negligible influence on ambient monoterpene mixing ratios, the average storm event increased mixing ratios by 0.59 ± 0.21 ppbv, a factor of 93% above pre-storm levels. In some events, mixing ratios reached the 10's of ppbv range and persisted overnight. These mixing ratios correspond to increases in the monoterpene emission rate, ranging from 120 to 1240 g km⁻² h⁻¹ compared to an estimated clear weather rate of 116 to 193 g km⁻² h⁻¹. Considering the regularity of storm events over most forested areas, this could be an important factor to consider when modeling global monoterpene emissions and their resulting influence on the formation of organic aerosols.

Experimental study of the crack depth ratio threshold to analyze the slow crack growth by creep of high density polyethylene pipes

International Nuclear Information System (INIS)

Laiarinandrasana, Lucien; Devilliers, Clémence; Lucatelli, Jean Marc; Gaudichet-Maurin, Emmanuelle; Brossard, Jean Michel

2014-01-01

To assess the durability of drinking water connection pipes subjected to oxidation and slow crack growth, a comprehensive database was constructed on a novel specimen geometry: the pre-cracked NOL ring. 135 tests were carried out consisting of initial crack depth ratio ranging from 0.08 to 0.6; single or double longitudinal cracks: tensile with steady strain rate and creep loading. A threshold value of the crack depth ratio of 0.2, induced by the oxidation was determined by analyzing several mechanical parameters. This threshold value was shown to be independent on the strain rate effects, single or double crack configuration and the kind of loading: tensile or creep. Creep test results with crack depth ratio larger than 0.2 were then utilized to establish a failure assessment diagram. A methodology allowing the prediction of residual lifetime of in-service pipes was proposed, using this diagram. - Highlights: • Experimental data on pre-cracked rings featuring a longitudinally cracked HDPE pipe. • Crack depth ratio threshold for slow crack growth study consecutive to oxidation. • Investigation of the effects of the single/double notch(es) and of the strain rate. • Original results obtained from tests performed with tensile and creep loadings. • Correlation between creep initiation time and C* with DENT and ring specimens

Risk Preferences and Predictions about Others: No Association with 2D:4D Ratio

Directory of Open Access Journals (Sweden)

Katharina Lima de Miranda

2018-02-01

Full Text Available Prenatal androgen exposure affects the brain development of the fetus which may facilitate certain behaviors and decision patterns in the later life. The ratio between the lengths of second and the fourth fingers (2D:4D is a negative biomarker of the ratio between prenatal androgen and estrogen exposure and men typically have lower ratios than women. In line with the typical findings suggesting that women are more risk averse than men, several studies have also shown negative relationships between 2D:4D and risk taking although the evidence is not conclusive. Previous studies have also reported that both men and women believe women are more risk averse than men. In the current study, we re-test the relationship between 2D:4D and risk preferences in a German student sample and also investigate whether the 2D:4D ratio is associated with people’s perceptions about others’ risk preferences. Following an incentivized risk elicitation task, we asked all participants their predictions about (i others’ responses (without sex specification, (ii men’s responses, and (iii women’s responses; then measured their 2D:4D ratios. In line with the previous findings, female participants in our sample were more risk averse. While both men and women underestimated other participants’ (non sex-specific and women’s risky decisions on average, their predictions about men were accurate. We also found evidence for the false consensus effect, as risky choices are positively correlated with predictions about other participants’ risky choices. The 2D:4D ratio was not directly associated either with risk preferences or the predictions of other participants’ choices. An unexpected finding was that women with mid-range levels of 2D:4D estimated significantly larger sex differences in participants’ decisions. This finding needs further testing in future studies.

Risk Preferences and Predictions about Others: No Association with 2D:4D Ratio

Science.gov (United States)

Lima de Miranda, Katharina; Neyse, Levent; Schmidt, Ulrich

2018-01-01

Prenatal androgen exposure affects the brain development of the fetus which may facilitate certain behaviors and decision patterns in the later life. The ratio between the lengths of second and the fourth fingers (2D:4D) is a negative biomarker of the ratio between prenatal androgen and estrogen exposure and men typically have lower ratios than women. In line with the typical findings suggesting that women are more risk averse than men, several studies have also shown negative relationships between 2D:4D and risk taking although the evidence is not conclusive. Previous studies have also reported that both men and women believe women are more risk averse than men. In the current study, we re-test the relationship between 2D:4D and risk preferences in a German student sample and also investigate whether the 2D:4D ratio is associated with people’s perceptions about others’ risk preferences. Following an incentivized risk elicitation task, we asked all participants their predictions about (i) others’ responses (without sex specification), (ii) men’s responses, and (iii) women’s responses; then measured their 2D:4D ratios. In line with the previous findings, female participants in our sample were more risk averse. While both men and women underestimated other participants’ (non sex-specific) and women’s risky decisions on average, their predictions about men were accurate. We also found evidence for the false consensus effect, as risky choices are positively correlated with predictions about other participants’ risky choices. The 2D:4D ratio was not directly associated either with risk preferences or the predictions of other participants’ choices. An unexpected finding was that women with mid-range levels of 2D:4D estimated significantly larger sex differences in participants’ decisions. This finding needs further testing in future studies. PMID:29472846

Alternative method for variable aspect ratio vias using a vortex mask

Science.gov (United States)

Schepis, Anthony R.; Levinson, Zac; Burbine, Andrew; Smith, Bruce W.

2014-03-01

Historically IC (integrated circuit) device scaling has bridged the gap between technology nodes. Device size reduction is enabled by increased pattern density, enhancing functionality and effectively reducing cost per chip. Exemplifying this trend are aggressive reductions in memory cell sizes that have resulted in systems with diminishing area between bit/word lines. This affords an even greater challenge in the patterning of contact level features that are inherently difficult to resolve because of their relatively small area and complex aerial image. To accommodate these trends, semiconductor device design has shifted toward the implementation of elliptical contact features. This empowers designers to maximize the use of free device space, preserving contact area and effectively reducing the via dimension just along a single axis. It is therefore critical to provide methods that enhance the resolving capacity of varying aspect ratio vias for implementation in electronic design systems. Vortex masks, characterized by their helically induced propagation of light and consequent dark core, afford great potential for the patterning of such features when coupled with a high resolution negative tone resist system. This study investigates the integration of a vortex mask in a 193nm immersion (193i) lithography system and qualifies its ability to augment aspect ratio through feature density using aerial image vector simulation. It was found that vortex fabricated vias provide a distinct resolution advantage over traditionally patterned contact features employing a 6% attenuated phase shift mask (APM). 1:1 features were resolvable at 110nm pitch with a 38nm critical dimension (CD) and 110nm depth of focus (DOF) at 10% exposure latitude (EL). Furthermore, iterative source-mask optimization was executed as means to augment aspect ratio. By employing mask asymmetries and directionally biased sources aspect ratios ranging between 1:1 and 2:1 were achievable, however, this

Mechanical evidence of the orbital angular momentum to energy ratio of vortex beams.

Science.gov (United States)

Demore, Christine E M; Yang, Zhengyi; Volovick, Alexander; Cochran, Sandy; MacDonald, Michael P; Spalding, Gabriel C

2012-05-11

We measure, in a single experiment, both the radiation pressure and the torque due to a wide variety of propagating acoustic vortex beams. The results validate, for the first time directly, the theoretically predicted ratio of the orbital angular momentum to linear momentum in a propagating beam. We experimentally determine this ratio using simultaneous measurements of both the levitation force and the torque on an acoustic absorber exerted by a broad range of helical ultrasonic beams produced by a 1000-element matrix transducer array. In general, beams with helical phase fronts have been shown to contain orbital angular momentum as the result of the azimuthal component of the Poynting vector around the propagation axis. Theory predicts that for both optical and acoustic helical beams the ratio of the angular momentum current of the beam to the power should be given by the ratio of the beam's topological charge to its angular frequency. This direct experimental observation that the ratio of the torque to power does convincingly match the expected value (given by the topological charge to angular frequency ratio of the beam) is a fundamental result.

Can T1 w/T2 w ratio be used as a myelin-specific measure in subcortical structures? Comparisons between FSE-based T1 w/T2 w ratios, GRASE-based T1 w/T2 w ratios and multi-echo GRASE-based myelin water fractions.

Science.gov (United States)

Uddin, Md Nasir; Figley, Teresa D; Marrie, Ruth Ann; Figley, Chase R

2018-03-01

Given the growing popularity of T 1 -weighted/T 2 -weighted (T 1 w/T 2 w) ratio measurements, the objective of the current study was to evaluate the concordance between T 1 w/T 2 w ratios obtained using conventional fast spin echo (FSE) versus combined gradient and spin echo (GRASE) sequences for T 2 w image acquisition, and to compare the resulting T 1 w/T 2 w ratios with histologically validated myelin water fraction (MWF) measurements in several subcortical brain structures. In order to compare these measurements across a relatively wide range of myelin concentrations, whole-brain T 1 w magnetization prepared rapid acquisition gradient echo (MPRAGE), T 2 w FSE and three-dimensional multi-echo GRASE data were acquired from 10 participants with multiple sclerosis at 3 T. Then, after high-dimensional, non-linear warping, region of interest (ROI) analyses were performed to compare T 1 w/T 2 w ratios and MWF estimates (across participants and brain regions) in 11 bilateral white matter (WM) and four bilateral subcortical grey matter (SGM) structures extracted from the JHU_MNI_SS 'Eve' atlas. Although the GRASE sequence systematically underestimated T 1 w/T 2 w values compared to the FSE sequence (revealed by Bland-Altman and mountain plots), linear regressions across participants and ROIs revealed consistently high correlations between the two methods (r 2 = 0.62 for all ROIs, r 2 = 0.62 for WM structures and r 2 = 0.73 for SGM structures). However, correlations between either FSE-based or GRASE-based T 1 w/T 2 w ratios and MWFs were extremely low in WM structures (FSE-based, r 2 = 0.000020; GRASE-based, r 2 = 0.0014), low across all ROIs (FSE-based, r 2 = 0.053; GRASE-based, r 2 = 0.029) and moderate in SGM structures (FSE-based, r 2 = 0.20; GRASE-based, r 2 = 0.17). Overall, our findings indicated a high degree of correlation (but not equivalence) between FSE-based and GRASE-based T 1 w/T 2 w ratios, and low correlations between T 1 w/T 2 w ratios and MWFs. This

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)

Reevaluation of the Solar Wind 36Ar/38Ar Ratio

Science.gov (United States)

Becker, R. H.; Schlutter, D. J.; Rider, P. E.; Pepin, R. O.

1996-03-01

The isotopic composition of solar wind (SW) argon is an important parameter in the modeling of the evolution of the terrestrial planet atmospheres. Anders and Grevesse assumed a 36Ar/38Ar ratio for SW of 5.31, essentially equal to that of air. Considerable evidence has since developed which indicates that this ratio is too low. Benkert et al. have reported their best estimate for the recent SW as 5.48 +/- 0.05, determined from measurements of lunar soil 71501. Based on Ar data obtained from surface oxidation of a metal separate from the Weston meteorite and from an uncontrolled etch of lunar sample 67701, reported by our group previously, we consider even this value to be too low. Since values of 5.75 to 5.85 were reported by Black for initial low temperature (fairly high SW 36Ar/38Ar ratio (in the range of ~5.6 to ~5.7), we decided to analyze Kapoeta for its light solar wind gases using the acid-etching techniques developed in our laboratory based on the CSSE procedure of Benkert et al.

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.

Long-range propagation of plasmon and phonon polaritons in hyperbolic-metamaterial waveguides

Science.gov (United States)

Babicheva, Viktoriia E.

2017-12-01

We study photonic multilayer waveguides that include layers of materials and metamaterials with a hyperbolic dispersion (HMM). We consider the long-range propagation of plasmon and phonon polaritons at the dielectric-HMM interface in different waveguide geometries (single boundary or different layers of symmetric cladding). In contrast to the traditional analysis of geometrical parameters, we make an emphasis on the optical properties of constituent materials: solving dispersion equations, we analyze how dielectric and HMM permittivities affect propagation length and mode size of waveguide eigenmodes. We derive figures of merit that should be used for each waveguide in a broad range of permittivity values as well as compare them with plasmonic waveguides. We show that the conventional plasmonic quality factor, which is the ratio of real to imaginary parts of permittivity, is not applicable to the case of waveguides with complex structure. Both telecommunication wavelengths and mid-infrared spectral ranges are of interest considering recent advances in van der Waals materials, such as hexagonal boron nitride. We evaluate the performance of the waveguides with hexagonal boron nitride in the range where it possesses hyperbolic dispersion (wavelength 6.3-7.3 μm), and we show that these waveguides with natural hyperbolic properties have higher propagation lengths than metal-based HMM waveguides.

Critical assessment of bone scan quantitation (bone to soft tissue ratios) in the diagnosis of metabolic bone disease

Energy Technology Data Exchange (ETDEWEB)

Fogelman, I.; Gordon, D.; Bessent, R.G.

1981-03-01

Accurate quantitation from the bone scan image of skeletal uptake of radiopharmaceutical would be of value in the assessment of patients with metabolic bone disease. Repeat measurements of bone to soft tissue (B/ST) ratios on the one set of images were made for 103 subjects, a) by the same observer using lumbar vertebra 2 for the area of bone; b) by the same observer using lumbar vertebra 2 then lumbar vertebra 4; c) by two observers both using lumbar vertebra 2. The median difference between repeat measurements by the same observer was well under 1% but the 5-95 percentile range was -13 to +14%. Between the two observers there was a median difference of 10.6% with a 5-95 percentile range of -11 to +44%. We also measured B/ST ratios in 150 control subjects and 139 patients with various metabolic bone disorders. While statistically significant differences for B/ST ratios were found between the osteomalacia, renal osteodystrophy, Paget's groups, and the control population (P < 0.001 in all cases), there was appreciable overlap between individual patient results and the control range. It is concluded, therefore, that measurement of B/ST ratios for the individual is of limited value in clinical practice.

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.