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Sample records for nonpiezoelectric-to-piezoelectric length ratio

  1. Finger Length Ratios in Serbian Transsexuals

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    Vujović, Svetlana; Popović, Srdjan; Mrvošević Marojević, Ljiljana; Ivović, Miomira; Tančić-Gajić, Milina; Stojanović, Miloš; Marina, Ljiljana V.; Barać, Marija; Barać, Branko; Kovačević, Milena; Duišin, Dragana; Barišić, Jasmina; Djordjević, Miroslav L.; Micić, Dragan

    2014-01-01

    Atypical prenatal hormone exposure could be a factor in the development of transsexualism. There is evidence that the 2nd and 4th digit ratio (2D : 4D) associates negatively with prenatal testosterone and positively with estrogens. The aim was to assess the difference in 2D : 4D between female to male transsexuals (FMT) and male to female transsexuals (MFT) and controls. We examined 42 MFT, 38 FMT, and 45 control males and 48 control females. Precise measurements were made by X-rays at the ventral surface of both hands from the basal crease of the digit to the tip using vernier calliper. Control male and female patients had larger 2D : 4D of the right hand when compared to the left hand. Control male's left hand ratio was lower than in control female's left hand. There was no difference in 2D : 4D between MFT and control males. MFT showed similar 2D : 4D of the right hand with control women indicating possible influencing factor in embryogenesis and consequently finger length changes. FMT showed the lowest 2D : 4D of the left hand when compared to the control males and females. Results of our study go in favour of the biological aetiology of transsexualism. PMID:24982993

  2. Finger Length Ratios in Serbian Transsexuals

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    Svetlana Vujović

    2014-01-01

    Full Text Available Atypical prenatal hormone exposure could be a factor in the development of transsexualism. There is evidence that the 2nd and 4th digit ratio (2D : 4D associates negatively with prenatal testosterone and positively with estrogens. The aim was to assess the difference in 2D : 4D between female to male transsexuals (FMT and male to female transsexuals (MFT and controls. We examined 42 MFT, 38 FMT, and 45 control males and 48 control females. Precise measurements were made by X-rays at the ventral surface of both hands from the basal crease of the digit to the tip using vernier calliper. Control male and female patients had larger 2D : 4D of the right hand when compared to the left hand. Control male’s left hand ratio was lower than in control female’s left hand. There was no difference in 2D : 4D between MFT and control males. MFT showed similar 2D : 4D of the right hand with control women indicating possible influencing factor in embryogenesis and consequently finger length changes. FMT showed the lowest 2D : 4D of the left hand when compared to the control males and females. Results of our study go in favour of the biological aetiology of transsexualism.

  3. Sexual dimorphism in digit length ratios in two lizard species.

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    Rubolini, Diego; Pupin, Fabio; Sacchi, Roberto; Gentilli, Augusto; Zuffi, Marco A L; Galeotti, Paolo; Saino, Nicola

    2006-05-01

    Sexual dimorphism in digit length ratios has been reported for humans, a few other mammals, and two bird species. This dimorphism is thought to arise via an interaction between the prenatal exposure of the embryo to sex hormones and the Hox genes, which are highly conserved among vertebrates and control the development of both the appendices, including fingers and toes, and the urogenital system. In this study, we report on sexual dimorphism in 2D:3D, 2D:4D, and 3D:4D contralateral ratios of the forelimbs in two species of oviparous lizards, the common wall lizard (Podarcis muralis) and the tree skink (Mabuya planifrons), as measured on museum specimens. We found that male P. muralis had a larger 2D:4D ratio on both sides and larger 2D:3D ratio on the left side than females, whereas in M. planifrons, males had lower 2D:3D ratios than females on the left side. The two species show opposite patterns of sexual dimorphism in body size, males being larger than females in P. muralis, and the reverse in M. planifrons, suggesting that interspecific variation of sex differences in digit ratios could be associated with sex-specific growth trajectories. There was a limited evidence for directional asymmetry in digit ratios. Therefore, our findings provide the first evidence that digit ratios are sexually dimorphic in any reptile species and are consistent with the idea that the genetic link between limb development and the urogenital system had been established with the evolution of the earliest terrestrial tetrapods. Importantly, many lizard species with genetic sex determination, including the ones we studied, are oviparous and may represent valuable animal models for experimental tests of the association between prenatal exposure to androgens or estrogens and digit ratios.

  4. Digit Ratios, Finger Length, and Basic Musical Abilities

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    Martin Voracek

    2009-01-01

    Full Text Available Among elite orchestra musicians (predominantly men, a lower (masculinised second-to-fourth digit ratio (2D:4D, a putative marker of prenatal testosterone levels, has been shown to be associated with higher musical-ability rankings (Sluming & Manning, 2000. Seeking to extend this evidence, this study examined associations of digit ratios (2D:4D and other and absolute finger length (a putative marker of pubertal-adolescent testosterone levels with basic musical abilities (Seashore battery in a sample of 124 adult non-musicians. Among women better pitch discrimination corresponded to lower (masculinised digit ratios and longer (masculinised fingers, whilst among men directionally opposite and thus not theory compliant correlations of rhythm and time discrimination with finger-length measures emerged. Similarly, although men exceeded women on most of the Seashore tasks, these sex differences were negligible, with the exception of timbre discrimination. On the whole, significant associations between the study variables were sparse and yielded little support for the assumption that prenatal or pubertal-adolescent androgen effects may partly influence within-sex individual variation in basic musical abilities among adult non-musicians.

  5. Does digit ratio (2DAD) predict penile length?

    Institute of Scientific and Technical Information of China (English)

    Denise Brooks McQuade

    2011-01-01

    @@ Now advertized in at least one locale as the 'sexy ratio' with the caption,'Your hands give away your hotness' (http://io9.com/#!5794008; accessed 3 May 2011),an online summary of a recent study linking facial attractiveness to the ratio of the index and ring fingers1 indicates that digit ratio (2DAD)research has reached mainstream culture.Digit ratio,most commonly the ratio of the index to ring fingers in humans,is sexually dimorphic (males have lower values than females) with greater differences on their right hand 2s Ratios are determined early in development and remain relatively stable thereafter.4 Perhaps the popular appeal is the relative simplicity of the measure,and the fact that researchers interested in any number of behavioral or physiological traits correlatedwith hormone activity have adopted digit ratio as a convenient biomarker for prenatal androgen exposure.5 Over the past decade,the correlation of digit ratio with sexual behavior and other aspects of reproductive biology has been well documented6-9 and there is a growing list of traits with links to digit ratio,although the associations are less well established.

  6. Ratio-based lengths of intervals to improve fuzzy time series forecasting.

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    Huarng, Kunhuang; Yu, Tiffany Hui-Kuang

    2006-04-01

    The objective of this study is to explore ways of determining the useful lengths of intervals in fuzzy time series. It is suggested that ratios, instead of equal lengths of intervals, can more properly represent the intervals among observations. Ratio-based lengths of intervals are, therefore, proposed to improve fuzzy time series forecasting. Algebraic growth data, such as enrollments and the stock index, and exponential growth data, such as inventory demand, are chosen as the forecasting targets, before forecasting based on the various lengths of intervals is performed. Furthermore, sensitivity analyses are also carried out for various percentiles. The ratio-based lengths of intervals are found to outperform the effective lengths of intervals, as well as the arbitrary ones in regard to the different statistical measures. The empirical analysis suggests that the ratio-based lengths of intervals can also be used to improve fuzzy time series forecasting.

  7. Jet length/velocity ratio: a new index for echocardiographic evaluation of chronic aortic regurgitation.

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    Güvenç, Tolga Sinan; Karaçimen, Denizhan; Erer, Hatice Betül; İlhan, Erkan; Sayar, Nurten; Karakuş, Gültekin; Çekirdekçi, Elif; Eren, Mehmet

    2015-01-01

    Management of aortic regurgitation depends on the assessment for severity. Echocardiography remains as the most widely available tool for evaluation of aortic regurgitation. In this manuscript, we describe a novel parameter, jet length/velocity ratio, for the diagnosis of severe aortic regurgitation. A total of 30 patients with aortic regurgitation were included to this study. Severity of aortic regurgitation was assessed with an aortic regurgitation index incorporating five echocardiographic parameters. Jet length/velocity ratio is calculated as the ratio of maximum jet penetrance to mean velocity of regurgitant flow. Jet length/velocity ratio was significantly higher in patients with severe aortic regurgitation (2.03 ± 0.53) compared to patients with less than severe aortic regurgitation (1.24 ± 0.32, P < 0.001). Correlation of jet length/velocity ratio with aortic regurgitation index was very good (r(2) = 0.86) and correlation coefficient was higher for jet length/velocity ratio compared to vena contracta, jet width/LVOT ratio and pressure half time. For a cutoff value of 1.61, jet length/velocity ratio had a sensitivity of 92% and specificity of 88%, with an AUC value of 0.955. Jet length/velocity ratio is a novel parameter that can be used to assess severity of chronic aortic regurgitation. Main limitation for usage of this novel parameter is jet impringement to left ventricular wall. © 2014, Wiley Periodicals, Inc.

  8. Prospective investigation of penile length with newborn male circumcision and second to fourth digit ratio

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    Park, Jong Kwan; Doo, A. Ram; Kim, Joo Heung; Park, Hyung Sub; Do, Jung Mo; Choi, Hwang; Park, Seung Chol; Kim, Myung Ki; Jeong, Young Beom; Kim, Hyung Jim; Kim, Young Gon; Shin, Yu Seob

    2016-01-01

    Introduction: We prospectively investigated the relationship between newborn male circumcision (NMC) and second to fourth digit ratio with penile length. Methods: As participants for our study, we identified already circumcised young patients who visited our hospital for urological treatment. The age at which the circumcision had been done was assessed. The patients’ height and weight were measured. Second to fourth digit ratio was calculated by measuring the second and fourth digit lengths. The flaccid and erectile penile lengths were measured from the base of the penis to the tip of the glans in standing position. Results: A total of 248 patients were included in our study. In univariate analysis, height, second to fourth digit ratio, flaccid penile length, and age of circumcision were associated with erectile penile length. Among these variables, second to fourth digit ratio, flaccid penile length, and age of circumcision were significant predictive factors for erectile penile length in multivariate analysis. The subjects were divided into two groups, including 72 patients in the NMC group and 176 patients in the non-NMC group. No significant difference was found in height, weight, and second to fourth digit ratio between both groups. However, flaccid (p<0.001) and erectile (p=0.001) penile lengths were shorter in the NMC group than in the non-NMC group. Conclusions: Despite the small number of subjects, this study shows that NMC was associated with shorter penile length. Second to fourth digit ratio, flaccid penile length, and age of circumcision were also significant predictive factors for erectile penile length. Further multicentre studies with larger number of subjects and biochemical analyses are needed for potential clinical applicability. PMID:27695583

  9. Mucosal cuff length to penile length ratio may affect the risk of premature ejaculation in circumcised males.

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    Yuruk, E; Temiz, M Z; Colakerol, A; Muslumanoglu, A Y

    2016-01-01

    Data regarding the relation between premature ejaculation (PE) and post-circumcision mucosal cuff length are controversial. The aim of this study is to analyze the relation between post-circumcision mucosal cuff length/penile length ratio (MCR) and PE. After exclusion of patients with erectile dysfunction, penile deformity, history of penile surgery and severe lower urinary tract symptoms, 49 circumcised men with PE were included. The control group is constituted of 50 healthy volunteers with normal ejaculatory function. Self-estimated intravaginal ejaculation latency time (IELT) and premature ejaculation profile (PEP) measures of all subjects were recorded, and the MCRs of patients and controls were compared. The mean age of PE patients and controls was 35.82 ± 7.73 (range 23-54) and 38.78 ± 13.42 (range 19-71) years, respectively (P=0.183). Although mucosal cuff length was not associated with either self-estimated IELT (r=-0.185, P=0.067) or PEP (r=-0.098, P=0.336), there was a negative correlation between MCR and self-estimated IELT (r=-0.205, P=0.0001) and PEP measures (r=-0.308, P=0.002). The length of the mucosal cuff after circumcision may have an impact on ejaculatory function. Surgeons should avoid leaving excessive amount of mucosa during circumcision.

  10. Second to fourth digit ratio: a predictor of adult penile length

    Institute of Scientific and Technical Information of China (English)

    In Ho Choi; Khae Hawn Kim; Han Jung; Sang Jin Yoon; Soo Woong Kim; Tae Beom Kim

    2011-01-01

    @@ The second to fourth digit ratio (2D:4D) has been proposed as a putative biomarker for prenatal testosterone and covaries with the sensitivity of the androgen receptor (AR).Both prenatal testosterone and the AR play a central role in penile growth.In this study,we investigated the relationship between digit ratio and penile length.Korean men who were hospitalized for urological surgery at a single tertiary academic centre were examined in this study,and 1[44]men aged 20 years or older who gave informed consent were prospectively enrolled.Right-hand second- and fourth-digit lengths were measured by a single investigator prior to measurement of penile length.Under anaesthesia,flaccid and stretched penile lengths were measured by another investigator who did not measure nor have any the information regarding the digit lengths.Univariate and multivariate analysis using linear regression models showed that only height was a significant predictive factor for flaccid penile length (univariate analysis: r=0.185,P=0.026; multivariate analysis:r=0.172,P=0.038) and that only digit ratio was a significant predictive factor for stretched penile length (univariate analysis:r=-0.216,P=0.009; multivariate analysis: r=-0.201,P=0.024; stretched penile length=-9.201 xdigit ratio+20.577).Based on this evidence,we suggest that the digit ratio can predict adult penile size and that the effects of prenatal testosterone may in part explain the differences in adult penile length.

  11. Nasal bone length, prenasal thickness, prenasal thickness-to-nasal bone length ratio and prefrontal space ratio in second- and third-trimester fetuses with Down syndrome.

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    Vos, F I; De Jong-Pleij, E A P; Bakker, M; Tromp, E; Pajkrt, E; Kagan, K O; Bilardo, C M

    2015-02-01

    To evaluate nasal bone length (NBL), prenasal thickness (PT), prenasal thickness-to-nasal bone length (PT-NBL) ratio and prefrontal space ratio (PFSR) as markers for Down syndrome in the second and third trimesters. NBL, PT, PT-NBL ratio and PFSR were measured retrospectively in stored two-dimensional images or three-dimensional volumes (corrected to the mid-sagittal plane) of fetuses with Down syndrome, which were retrieved from the digital databases of participating units. Measurements were performed on the stored images and volumes by two experienced operators, and the values obtained were compared to our previously reported normal ranges for euploid fetuses in order to assess the detection rates for Down syndrome. A total of 159 fetuses with Down syndrome were included in the analysis, six of which were excluded because of inadequate available images. Median maternal age was 36.0 years and median gestational age was 23 + 1 weeks. NBL and PT were correlated with gestational age (P Down syndrome, the PT-NBL ratio yielded the highest detection rate (86.2%), followed by PFSR (79.7%), PT (63.4%) and NBL (61.9%). All markers were abnormal in 33.6% of cases, whilst all were normal in 4.7%. At least one of the four markers was abnormal in 95.3%, and either the PT-NBL ratio or PFSR was abnormal in 93.8%. Detection rates were not related to gestational age. The PT-NBL ratio and PFSR are robust second- and third-trimester markers for Down syndrome. Both provide high detection rates and are easy to use, as the cut-off for normality is constant throughout gestation. Ltd. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  12. Nano-scaled graphene platelets with a high length-to-width aspect ratio

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    Zhamu, Aruna; Guo, Jiusheng; Jang, Bor Z.

    2010-09-07

    This invention provides a nano-scaled graphene platelet (NGP) having a thickness no greater than 100 nm and a length-to-width ratio no less than 3 (preferably greater than 10). The NGP with a high length-to-width ratio can be prepared by using a method comprising (a) intercalating a carbon fiber or graphite fiber with an intercalate to form an intercalated fiber; (b) exfoliating the intercalated fiber to obtain an exfoliated fiber comprising graphene sheets or flakes; and (c) separating the graphene sheets or flakes to obtain nano-scaled graphene platelets. The invention also provides a nanocomposite material comprising an NGP with a high length-to-width ratio. Such a nanocomposite can become electrically conductive with a small weight fraction of NGPs. Conductive composites are particularly useful for shielding of sensitive electronic equipment against electromagnetic interference (EMI) or radio frequency interference (RFI), and for electrostatic charge dissipation.

  13. FETAL GESTATIONAL AGE ESTIMATION BY FETAL FOOT LENGTH MEASUREMENT AND FETAL FEMUR TO FOOT LENGTH RATIO IN INDIAN POPULATION - A PROSPECTIVE STUDY

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    Mukta

    2014-03-01

    Full Text Available BACKGROUND: Multiple parameters are in use for the accurate assessment of the gestational age by ultrasound, but the literature suggests that fetal foot length can be used to estimate gestational age, when other parameters are not available for measurement. Foetal femur/ foot length ratio can help in differentiating the foeti that have dysplastic limb reduction, from those whose limbs are short because of constitutional factors/IUGR. A prospective study was done to measure the fetal foot length for gestational age and to evaluate fetal femur to foot length ratio in pregnant women of 16-37 weeks gestation. MATERIALS & METHOD: One hundred and three normal singleton pregnant women of 16-37 weeks gestation were examined for routine obstetrics ultrasound. In these patients fetal foot length measurements were taken and the gestational age was assessed. In addition, fetal femur length to foot length ratio was calculated in each patient. RESULTS/OBSERVATION: Linear relationship between foot length and gestational age was present with a R2 value of 0.90 (p < than 0.001 and the fetal femur length/foot length ratio was found to be more than or equal to 0.92.The foot length can be a reliable parameter for use in assessment of gestational age and as most skeletal dysplasias spare the feet, the fetal femur length/foot length ratio can be used to detect most skeletal dysplasia. CONCLUSIONS: Foetal foot length is a reliable parameter for assessment of gestational age and femur length/foot length ratio is approximately 1 and a ratio of < 0.92 shall be useful in the detection of most skeletal dysplasia.

  14. The Relationship of Body Length and Ratio Pappilla with Sex in Gobi Fish (Sicyopterus macrostetholepis

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    Rona Taula Sari

    2017-07-01

    Full Text Available Research about the relationship of body length and ratio papilla with sex in goby fish (S. macrostetholepis Blkr. has been done at Animal Structure and Developmental Laboratory, Biologi Department, Faculty of Matematics and Natural Sciences, Andalas University, Padang, which purposed to analyse the relationship of body length and ratio papilla with sex of goby fish (S. macrostetholepis Blkr.. The samples were taken in wild stream area at Batangkuranji river, Padang City. This research used descriptive method and data were analyzed by qualitatively and quantitatively. The results of investigation showed that in several goby fishes (S. macrostetholepis Blkr. with different sex had the same of body length and the same of ratio papilla. So, there was not relationship between of body length and ratio papilla with sex.  Goby fishes (S. macrostetholepis Blkr. it belongs to the hermaphrodite protogini, which the androgynous young females, while in adulthood, it would change sex to male. The results of this study are expected to add to the treasures of knowledge and information about reproductive gobies (S. macrostetholepis Blkr. in the preservation and development of fish farming.   

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

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

    1975-01-01

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

  16. Dependence of effective screening length in granular columns on bead and silo sizes and their ratio

    Institute of Scientific and Technical Information of China (English)

    Abdul Qadir; Madad Ali Shah; Saeed Ahmed Khan

    2013-01-01

    Apparent mass measurements at the bottom of silos have been carried out.An important parameter in the Janssen model known as the effective screening length has been investigated for different bead and silo diameters as well as of their ratios.It is found that the effective screening length augments with the grain diameter d in addition to the granular column size.It is also revealed that λ exhibits stronger correlation with the bead diameter than that of the silo.This phenomenon is attributed to the reduced-shielding of the vertical stresses to the horizontal ones.

  17. Dependence of effective screening length in granular columns on bead and silo sizes and their ratio

    Science.gov (United States)

    Abdul, Qadir; Madad, Ali Shah; Saeed, Ahmed Khan

    2013-05-01

    Apparent mass measurements at the bottom of silos have been carried out. An important parameter in the Janssen model known as the effective screening length has been investigated for different bead and silo diameters as well as of their ratios. It is found that the effective screening length augments with the grain diameter d in addition to the granular column size. It is also revealed that λ exhibits stronger correlation with the bead diameter than that of the silo. This phenomenon is attributed to the reduced-shielding of the vertical stresses to the horizontal ones.

  18. On the Elastic Vibration Model for High Length-Diameter Ratio Rocket with Attitude Control System

    Institute of Scientific and Technical Information of China (English)

    朱伯立; 杨树兴

    2003-01-01

    An elastic vibration model for high length-diameter ratio spinning rocket with attitude control system which can be used for trajectory simulation is established. The basic theory of elastic dynamics and vibration dynamics were both used to set up the elastic vibration model of rocket body. In order to study the problem more conveniently, the rocket's body was simplified to be an even beam with two free ends. The model was validated by simulation results and the test data.

  19. CFD simulation of length to diameter ratio effects on the energy separation in a vortex tube

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    Bramo Reza Abdol

    2011-01-01

    Full Text Available The objective of the present computational fluid dynamics analysis is an attempt to investigate the effect of length to diameter ratio on the fluid flow characteristics and energy separation phenomenon inside the Ranque-Hilsch vortex tube. In this numerical study, performance of Ranque-Hilsch vortex tubes (RHVT, with length to diameter ratios (L/D of 8, 9.3, 10.5, 20.2, 30.7 and 35 with six straight nozzles was investigated. It includes generating better understanding of the effects of the stagnation point location on the performance of RHVT. It was found that the best performance was obtained when the ratio of vortex tube length to the diameter was 9.3 and also fort this case the stagnation point was found to be the farthest from the inlet. The results show that the closer distance to the hot end is produced the larger magnitude of the temperature difference. Computed results show good agreement with published experimental results.

  20. Effect of grain port length-diameter ratio on combustion performance in hybrid rocket motors

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    Cai, Guobiao; Zhang, Yuanjun; Tian, Hui; Wang, Pengfei; Yu, Nanjia

    2016-11-01

    The objectives of this study are to develop a more accurate regression rate considering the oxidizer mass flow and the fuel grain geometry configuration with numerical and experimental investigations in polyethylene (PE)/90% hydrogen peroxide (HP) hybrid rocket. Firstly, a 2-D axisymmetric CFD model with turbulence, chemistry reaction, solid-gas coupling is built to investigate the combustion chamber internal flow structure. Then a more accurate regression formula is proposed and the combustion efficiency changing with the length-diameter ratio is studied. A series experiments are conducted in various oxidizer mass flow to analyze combustion performance including the regression rate and combustion efficiency. The regression rates are measured by the fuel mass reducing and diameter changing. A new regression rate formula considering the fuel grain configuration is proposed in this paper. The combustion efficiency increases with the length-diameter ratio changing. To improve the performance of a hybrid rocket motor, the port length-diameter ratio is suggested 10-12 in the paper.

  1. Seed-Mediated Growth of Gold Nanorods: Limits of Length to Diameter Ratio Control

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    Christopher J. Ward

    2014-01-01

    Full Text Available The effects of the seed reaction conditions on the two-step seed-mediated growth of gold nanorods and the effect of gold and reducing agent content in the growth solution were evaluated. Results indicate that the reaction conditions used to produce the seeds have a significant impact on the aspect ratio of the gold nanorods produced. Increasing the concentration of gold or the reaction temperature in the seed production step results in lower length to diameter (aspect ratio gold rods. In addition, the amount of prepared seed added to the growth solution impacts the rod aspect ratio, with increasing amounts of seed reducing the aspect ratio. The effects of reducing agent, ascorbic acid (AA, and gold content of the growth solution on the aspect ratio of the produced rods are strongly interrelated. There exists a minimum ascorbic acid to gold concentration below which rods will not form; however, increasing the ratio above this minimum results in shorter rods being formed. Characterization of nanorod growth is performed by UV-vis-NIR spectrophotometry and transmission electron microscopy (TEM.

  2. Optimal Limb Length Ratio of Quadruped Robot Minimising Joint Torque on Slopes

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    Tadayoshi Aoyama

    2009-01-01

    Full Text Available This paper aims to determine an optimal structure for a quadruped robot, which will allow the robot’s joint torque sum to be minimised. An animal’s characteristic limb length ratio is a vital part of its overall morphology and the one that enables it to travel easily through its environment. For the same reason, a robot’s structure needs to be suitably designed for locomotion in its working environment. Joint torques are necessary to maintain the posture of the robot and to accelerate joint angles during walking motion, hence, minimisation of joint torques reduces energy consumption. We performed a numerical simulation in which we analysed the joint torques for various limb lengths and slope angles in order to determine the optimal structure of a robot walking on a slope. Our investigation determines that the optimal Ratio of Rear Leg Length (RRL can be derived by the use of a simulation designed to determine the physical structure of quadruped robot. Our analysis suggests that joint torque will increase as the slope angle becomes steeper if the rear legs of the robot are shorter than its forelegs, and that joint torque will decrease as the slope angle declines if the robot’s forelegs are shorter than its rear legs. Finally, experimental results validated our simulation analysis.

  3. Effects of varying inter-limb spacing to limb length ratio in metachronal swimming

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    Lai, Hong Kuan; Merkel, Rachael; Santhanakrishnan, Arvind

    2016-11-01

    Crustaceans such as shrimp, krill and crayfish swim by rhythmic paddling of four to five pairs of closely spaced limbs. Each pair is phase-shifted in time relative to the neighboring pair, resulting in a metachronal wave that travels in the direction of animal motion. The broad goal of this study is to investigate how the mechanical design of the swimming limbs affect scalability of metachronal swimming in terms of limb-based Reynolds number (Re). A scaled robotic model of metachronal paddling was developed, consisting of four pairs of hinged acrylic plates actuated using stepper motors that were immersed in a rectangular tank containing water-glycerin fluid medium. 2D PIV measurements show that the propulsive jets transition from being primarily horizontal (thrust-producing direction) at Re of order 10 to angled vertically at Re of order 100. The ratio of inter-limb spacing to limb length among metachronal swimming organisms ranges between 0.2 to 0.65. 2D PIV will be used to examine the jets generated between adjacent limbs for varying inter-limb spacing to limb length ratios. The effect of increasing this ratio to beyond the biologically observed range will be discussed.

  4. The ratio of intracellular CRY proteins determines the clock period length

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    Li, Yang [College of Biological Sciences, China Agricultural University, Beijing 100083 (China); National Institute of Biological Sciences, Beijing 102206 (China); Xiong, Wei [National Institute of Biological Sciences, Beijing 102206 (China); School of Life Sciences, Peking University, Beijing 100871 (China); Zhang, Eric Erquan, E-mail: zhangerquan@nibs.ac.cn [National Institute of Biological Sciences, Beijing 102206 (China)

    2016-04-08

    Although a deficiency in CRY1 or CRY2 correlates with a shorter or longer circadian period, the regulation of CRY proteins in the circadian period has not been well studied. In this study, we found that both CRY1 and CRY2 were able to rescue oscillation in CRY null cells and that they displayed different periods. Furthermore, we demonstrated that protein nuclear import rates, not protein stability, regulate the period-length at the cellular level. Co-transfection of CRY1 and CRY2 in various ratios in the same cells gives rise to the predicted period length in a dose-dependent manner. Given the distinct characteristics of the C-terminal tails of the CRY1 and CRY2 proteins, our study addresses a long-standing hypothesis that the ratio of these two CRY molecules affects the clock period. - Highlights: • Rhythmic CRY2, like CRY1, in the correct CRY1 phase is sufficient to rescue clock oscillation in CRY null cells. • The short-period mammalian CRY2 protein is more stable than the CRY1 protein. • The N-terminal polypeptide of CRY2 contributes to its stability and Per2 repression, but it does not affect the period. • The C-terminal tails of CRYs regulate their protein stability and nuclear import, but the import rate governs the period. • The ratio, rather than the absolute amounts of CRY1 and CRY2 proteins, determines the period in mammalian cells.

  5. Relationship between width and length ratios of upper anterior teeth in young Chilean population.

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    Jorge Troncoso-Pazos

    2017-08-01

    Full Text Available Introduction: Knowledge about the size and proportion of upper anterior teeth allows dental rehabilitation taking into consideration the local parameters of a population. The aim of this research is to determine the width, length and the relationship between width and length of central incisor, lateral incisor and canine teeth in both sexes in young Chilean population. Methodology: A cross-sectional study was performed. Study subjects included 187 dentistry students from two Chilean cities (mean age 21.35±2.7 years, 52.9% men. The teeth width and height were measured and the width/height ratio was calculated. Differences in measurements according to sex was analyzed (p<0.05; STATA v.10.0. Results: The width and height of the teeth were statistically and proportionally larger in men (p<0.05. The width/height ratio of lateral and canine incisors was significantly higher in women (p<0.05. Conclusion: In a sample of young Chileans, upper anterior teeth were longer and wider in men. However, the width/height ratio of teeth was found to be significantly higher in women.

  6. Ultrasonographic measurement of fetal foot length and femur/foot length ratio in second trimester of normal pregnancy tn Korean women

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Eun Kyung [Pochon CHA Univ. College of Medicine, Seoul (Korea, Republic of)

    2001-06-01

    The aim of this study was to determine, using prenatal ultrasongraphy, normal fetal foot length and the femur length ratio during the second trimester of a normal pregnancy in Korean women. From May to July 1999, and in September of the same year, 1018 normal Korean singleton pregnancies showing no abnormality on prenatal sonograms were included in this study. The gestational age ranged from 19 to 30 weeks. Femur and foot length were measured by one radiologist. Regression analysis was performed for foot length and gestational age, and the mean value of the femur/foot length ratio and 95th percentile confidence interval of that mean value were calculated. The data obtained was compared with that obtained from caucasians. Foot length correlated with gestational age (r{sup 2}=0.87, {rho} value= 0.0001). The regression formula was as follows; Gestational age (days) = 70.98-2.15 X foot length (mm). Mean foot length at each gestational week was not different from the corresponding figure for Cancasians. The mean ({+-}SD) value of the femur/foot length ratio was 0.96 ({+-}0.05) and the 95{sup th} percentile confidence interval of that mean value was 0.96{+-} 0.000301, figures which are significantly lower than those for Caucasians. Fetal foot length during the second trimester of a normal pregnancy in Korean women is a reliable parameter for use in the assessment of gestational age. In our study the fetal foot length was not different from that of caucasians, while the femur/foot length ratio was lower than the value in that group. The nomogram depicted in of this study will serve as a useful adjunct in the screening of chromosomal abnormality or skeletal dysplasia among Koreans.

  7. 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.

  8. INCLUSION RATIO BASED ESTIMATOR FOR THE MEAN LENGTH OF THE BOOLEAN LINE SEGMENT MODEL WITH AN APPLICATION TO NANOCRYSTALLINE CELLULOSE

    Directory of Open Access Journals (Sweden)

    Mikko Niilo-Rämä

    2014-06-01

    Full Text Available A novel estimator for estimating the mean length of fibres is proposed for censored data observed in square shaped windows. Instead of observing the fibre lengths, we observe the ratio between the intensity estimates of minus-sampling and plus-sampling. It is well-known that both intensity estimators are biased. In the current work, we derive the ratio of these biases as a function of the mean length assuming a Boolean line segment model with exponentially distributed lengths and uniformly distributed directions. Having the observed ratio of the intensity estimators, the inverse of the derived function is suggested as a new estimator for the mean length. For this estimator, an approximation of its variance is derived. The accuracies of the approximations are evaluated by means of simulation experiments. The novel method is compared to other methods and applied to real-world industrial data from nanocellulose crystalline.

  9. Phenotypic features in autistic individuals: the finger length ratio (2D:4D), hair whorl, and hand dominance

    National Research Council Canada - National Science Library

    Aksu, Funda; Baykara, Burak; Ergın, Canem; Arman, Candan

    2013-01-01

    The aim of this study was to compare the finger length ratio (2D:4D), hair whorl direction, and hand, foot, and eye dominance in autistic and healthy individuals, and to investigate the phenotypic characteristics of autism...

  10. Environmental Assessment of a Diesel Engine Under Variable Stroke Length and Constant Compression Ratio

    Directory of Open Access Journals (Sweden)

    Jehad A.A. Yamin

    2007-01-01

    Full Text Available In the light of the energy crisis and the stringent environmental regulations, diesel engines are offering good hope for automotive vehicles. However, lot of work is needed to reduce the diesel exhaust emissions and give the way for full utilization of the diesel fuel’s excellent characteristics. This paper presents a theoretical study on the effect of variable stroke length technique on the emissions of a four-stroke, water-cooled direct injections diesel engine with the help of experimentally verified computer software designed mainly for diesel engines. The emission levels were studied over the speed range (1000 rpm to 3000 rpm and stroke lengths (120 mm to 200 rpm and were compared with those of the original engine design. The simulation results clearly indicate the advantages and utility of variable stroke technique in the reduction of the exhaust emission levels. A reduction of about 10% to 75% was achieved for specific particulate matter over the entire speed range and bore-to-stroke ratio studied. Further, a reduction of about 10% to 59% was achieved for the same range. As for carbon dioxide, a reduction of 0% to 37% was achieved. On the other hand, a less percent change was achieved for the case of nitrogen dioxide and nitrogen oxides as indicated by the results. This study clearly shows the advantage of VSE over fixed stroke engines. This study showed that the variable stroke technique proved a good way to curb the diesel exhaust emissions and hence helped making these engines more environmentally friendly.

  11. An Evaluation of Leaf Biomass : Length Ratio as a Tool for Nondestructive Assessment in Eelgrass (Zostera marina L.

    Directory of Open Access Journals (Sweden)

    Hector Echavarria-Heras

    2012-01-01

    Full Text Available The characterization of biomass and its dynamics provides valuable information for the assessment of natural and transplanted eelgrass populations. The need for simple, nondestructive assessments has led to the use of the leaf biomass-to-length ratio for converting leaf-length measurements, which can be easily obtained, to leaf growth rates through the plastochrone method. Using data on leaf biomass and length collected in three natural eelgrass populations and a mesocosm, we evaluated the suitability of a leaf weight-to-length ratio for nondestructive assessments. For the data sets considered, the isometric scaling that sustains the weight-to-length proxy always produced inconsistent fittings, and for leaf-lengths greater than a threshold value, the conversion of leaf length to biomass generated biased estimations. In contrast, an allometric scaling of leaf biomass and length was highly consistent in all the cases considered. And these nondestructive assessments generated reliable levels of reproducibility in leaf biomass for all the ranges of variability in leaf lengths. We argue that the use of allometric scaling for the representation of leaf biomass in terms of length provides a more reliable approach for estimating eelgrass biomass.

  12. Changes of Root Length and Root-to-Crown Ratio after Apical Surgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Jensen, Simon S; Bornstein, Michael M

    2015-01-01

    the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. METHODS: In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47...

  13. Finger length ratio (2D:4D) correlates with physical aggression in men but not in women.

    Science.gov (United States)

    Bailey, Allison A; Hurd, Peter L

    2005-03-01

    Finger length ratio (2D:4D) is a sexually dimorphic trait. Men have relatively shorter second digits (index fingers) than fourth digits (ring fingers). Smaller, more masculine, digit ratios are thought to be associated with either higher prenatal testosterone levels or greater sensitivity to androgens, or both. Men with more masculine finger ratios are perceived as being more masculine and dominant by female observers, and tend to perform better in a number of physical sports. We hypothesized that digit ratio would correlate with propensity to engage in aggressive behavior. We examined the relationship between trait aggression, assayed using a questionnaire, and finger length ratio in both men and women. Men with lower, more masculine, finger length ratios had higher trait physical aggression scores (r(partial) = -0.21, N = 134, P = 0.028). We found no correlation between finger length ratio and any form of aggression in females. These results are consistent with the hypothesis that testosterone has an organizational effect on adult physical aggression in men.

  14. Effects of cigarette smoking and nicotine metabolite ratio on leukocyte telomere length.

    Science.gov (United States)

    Verde, Zoraida; Reinoso-Barbero, Luis; Chicharro, Luis; Garatachea, Nuria; Resano, Pilar; Sánchez-Hernández, Ignacio; Rodríguez González-Moro, Jose Miguel; Bandrés, Fernando; Santiago, Catalina; Gómez-Gallego, Félix

    2015-07-01

    Studies of the effects of smoking on leukocyte telomere length (LTL) using cigarettes smoked per day or pack years smoked (PYS) present limitations. Reported high levels of smoking may not increase toxin exposure levels proportionally. Nicotine metabolism ratio (NMR) predicts total cigarette puff volume and overall exposure based on total N-nitrosamines, is highly reproducible and independent of time since the last cigarette. We hypothesized that smokers with higher NMRs will exhibit increased total puff volume, reflecting efforts to extract more nicotine from their cigarettes and increasing toxin exposure. In addition, higher levels of smoking could cause a gross damage in LTL. The urinary cotinine, 3-OH cotinine and nicotine levels of 147 smokers were analyzed using a LC/MS system Triple-Q6410. LTL and CYP2A6 genotype was determined by PCR in blood samples. We found a significant association between NMR and CYP2A6 genotype. Reduction in LTL was seen in relation to accumulated tobacco consumption and years smoking when we adjusted for age and gender. However, there were no significant differences between NMR values and LTL. In our study the higher exposure was associated with lower number of PYS. Smokers with reduced cigarette consumption may exhibit compensatory smoking behavior that results in no reduced tobacco toxin exposure. Our results suggest that lifetime accumulated smoking exposure could cause a gross damage in LTL rather than NMR or PYS. Nevertheless, a combination of smoking topography (NMR) and consumption (PYS) measures may provide useful information about smoking effects on health outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Maternal Lineage of Warmblood Mares Contributes to Variation of Gestation Length and Bias of Foal Sex Ratio.

    Science.gov (United States)

    Kuhl, J; Stock, K F; Wulf, M; Aurich, C

    2015-01-01

    Maternal lineage influences performance traits in horses. This is probably caused by differences in mitochondrial DNA (mtDNA) transferred to the offspring via the oocyte. In the present study, we investigated if reproductive traits with high variability-gestation length and fetal sex ratio-are influenced by maternal lineage. Data from 142 Warmblood mares from the Brandenburg State Stud at Neustadt (Dosse), Germany, were available for the study. Mares were grouped according to their maternal lineage. Influences on the reproduction parameters gestation length and sex ratio of offspring were analyzed by simple and multiple analyses of variance. A total of 786 cases were included. From the 142 mares, 119 were assigned to six maternal lineages with n≥10 mares per lineage, and 23 mares belonged to smaller maternal lineages. The mean number of live foals produced per mare was 4.6±3.6 (±SD). Live foal rate was 83.5%. Mean gestation length was 338.5±8.9 days (±SD) with a range of 313 to 370 days. Gestation length was affected by maternal lineage (pGestation length was also significantly influenced by the individual mare, age of the mare, year of breeding, month of breeding and sex of the foal (pgestation length and foal sex ratio in horses. In young primiparous and aged mares, the percentage of female offspring is higher than the expected 1:1 ratio.

  16. Walk Ratio (Step Length/Cadence) as a Summary Index of Neuromotor Control of Gait: Application to Multiple Sclerosis

    Science.gov (United States)

    Rota, Viviana; Perucca, Laura; Simone, Anna; Tesio, Luigi

    2011-01-01

    In healthy adults, the step length/cadence ratio [walk ratio (WR) in mm/(steps/min) and normalized for height] is known to be constant around 6.5 mm/(step/min). It is a speed-independent index of the overall neuromotor gait control, in as much as it reflects energy expenditure, balance, between-step variability, and attentional demand. The speed…

  17. Maternal Lineage of Warmblood Mares Contributes to Variation of Gestation Length and Bias of Foal Sex Ratio.

    Directory of Open Access Journals (Sweden)

    J Kuhl

    Full Text Available Maternal lineage influences performance traits in horses. This is probably caused by differences in mitochondrial DNA (mtDNA transferred to the offspring via the oocyte. In the present study, we investigated if reproductive traits with high variability-gestation length and fetal sex ratio-are influenced by maternal lineage. Data from 142 Warmblood mares from the Brandenburg State Stud at Neustadt (Dosse, Germany, were available for the study. Mares were grouped according to their maternal lineage. Influences on the reproduction parameters gestation length and sex ratio of offspring were analyzed by simple and multiple analyses of variance. A total of 786 cases were included. From the 142 mares, 119 were assigned to six maternal lineages with n≥10 mares per lineage, and 23 mares belonged to smaller maternal lineages. The mean number of live foals produced per mare was 4.6±3.6 (±SD. Live foal rate was 83.5%. Mean gestation length was 338.5±8.9 days (±SD with a range of 313 to 370 days. Gestation length was affected by maternal lineage (p<0.001. Gestation length was also significantly influenced by the individual mare, age of the mare, year of breeding, month of breeding and sex of the foal (p<0.05. Of the 640 foals born alive at term, 48% were male and 52% female. Mare age group and maternal lineage significantly influenced the sex ratio of the foals (p<0.05. It is concluded that maternal lineage influences reproductive parameters with high variation such as gestation length and foal sex ratio in horses. In young primiparous and aged mares, the percentage of female offspring is higher than the expected 1:1 ratio.

  18. Does an Arithmetic Coding Followed by Run-length Coding Enhance the Compression Ratio?

    Directory of Open Access Journals (Sweden)

    Mohammed Otair

    2015-07-01

    Full Text Available Compression is a technique to minimize the quantity of image without excessively decreasing the quality of the image. Then, the translating of compressed image is much more efficient and rapidly than original image. Arithmetic and Huffman coding are mostly used techniques in the entropy coding. This study tries to prove that RLC may be added after Arithmetic coding as an extra processing step which may therefore be coded efficiently without any further degradation of the image quality. So, the main purpose of this study is to answer the following question "Which entropy coding, arithmetic with RLC or Huffman with RLC, is more suitable from the compression ratio perspective?" Finally, experimental results show that an Arithmetic followed by RLC coding yields better compression performance than Huffman with RLC coding.

  19. Gestation length, birth weight and offspring gender ratio of in vitro-produced Gyr (Bos indicus) cattle embryos.

    Science.gov (United States)

    Camargo, Luiz Sergio Almeida; Freitas, Celio; de Sa, Wanderlei Ferreira; de Moraes Ferreira, Ademir; Serapiao, Raquel Varela; Viana, João Henrique Moreira

    2010-07-01

    In vitro embryo production (IVP) has been suggested to result in a greater proportion of male calves, longer gestation and heavier offspring than artificial insemination in Bos taurus cattle. Despite the increasing use of IVP in tropical countries, its effects upon these traits in Bos indicus have not been conclusively investigated. Gyr is a B. indicus dairy breed with known physiological differences from B. taurus, such as a longer gestation period and lighter offspring. The aim of this study was to evaluate the effect of IVP on gestation length, birth weight and gender ratio in Gyr offspring. Oocytes were recovered from Gyr cows by ovum pick-up and were matured and fertilized with thawed Gyr semen in vitro. Embryos were cultured in CR2aa medium with cumulus cells and 10% fetal calf serum under 5% CO(2) at 38.5 degrees C in air. Seven- to eight-day blastocysts were transferred to synchronized recipients. Data on gestation length and birth weight of calves from in vitro-produced embryos were compared to data obtained from Gyr calves produced by artificial insemination (AI) and natural breeding (NB) during the same period using analysis of variance, and the gender ratio was compared to the expected 1:1 ratio using a chi-square test. IVP increased (P0.05) was observed in the AI and NB groups. Gestation length was similar (P>0.05) between the IVP and AI groups, but IVP-derived offspring were heavier (P<0.05) than AI- and NB-derived ones, mainly for male calves (P<0.05). These data show that in vitro production affects the subsequent development of Gyr embryos, resulting in a skewed sex ratio and increased birth weight.

  20. A modified method for determining the focal ratio degradation and length properties of optical fibres in astronomy

    Science.gov (United States)

    Yan, Yunxiang; Wang, Gang; Sun, Weimin; Luo, A.-Li; Ma, Zhenyu; Li, Jian; Wang, Shuqing

    2017-04-01

    Focal ratio degradation (FRD) is a major contributor to throughput and light loss in a fibre spectroscopic telescope system. We combine the guided mode theory in geometric optics and a well-known model, the power distribution model (PDM), to predict and explain the FRD dependence properties. We present a robust method by modifying the energy distribution method with f-intercept to control the input condition. This method provides a way to determine the proper position of the fibre end on the focal plane to improve energy utilization and FRD performance, which lifts the relative throughput up to 95 per cent with variation of output focal ratio less than 2 per cent. This method can also help to optimize the arrangement of the position of focal-plane plate to enhance the coupling efficiency in a telescope. To investigate length properties, we modified the PDM by introducing a new parameter, the focal distance f, into the original model to make it available for a multiposition measurement system. The results show that the modified model is robust and feasible for measuring the key parameter d0 to simulate the transmission characteristics. The output focal ratio in the experiment does not follow the prediction trend but shows an interesting phenomenon: the output focal ratio increases first to the peak, then decreases and remains stable finally with increasing fibre length longer than 15 m. This provides a reference for choosing the appropriate length of fibre to improve the FRD performance for the design of the fibre system in a telescope.

  1. The Ratio of Second to Fourth Digit Length (2D:4D in Children with Autistic Disorder

    Directory of Open Access Journals (Sweden)

    Javad Baharara

    2014-11-01

    Full Text Available Introduction Emerging hypotheses suggest a causal role for prenatal androgen exposure in some cases of Autism spectrum disorders (ASD. The ratios of the lengths of the bones of the 2nd to the 4th digits (2D:4D are purported to be markers for prenatal androgen exposure and to be established early in gestation. Ratio of second and fourth digits (2D:4D  is usually used as a proxy for prenatal testosterone. Methods and Materials In this study, 2D:4D in 48 children with ASD and in 41  control child was measured. Two groups were matched with the gender and age. Both groups were selected by convenience sampling method. All statistical analyses were performed using SPSS 19.0 software, considering as significant less than .05 (p < .05. Results: Results showed that the average ratio of 2D:4D in ASD children were lower than the ratio in control children (P

  2. Optimizing loading path and die linetype of large length-to-diameter ratio metal stator screw lining hydroforming

    Institute of Scientific and Technical Information of China (English)

    祝效华; 石昌帅; 童华

    2015-01-01

    In order to meet the high temperature environment requirement of deep and superdeep well exploitation, a technology of large length-to-diameter ratio metal stator screw lining meshing with rotor is presented. Based on the elastic-plasticity theory, and under the consideration of the effect of tube size, material mechanical parameters, friction coefficient and loading paths, the external pressure plastic forming mechanical model of metal stator screw lining is established, to study the optimal loading path of metal stator lining tube hydroforming process. The results show that wall thickness reduction of the external pressure tube hydroforming (THF) is about 4%, and three evaluation criteria of metal stator screw lining forming quality are presented: fillet stick mold coefficient, thickness relative error and forming quality coefficient. The smaller the three criteria are, the better the forming quality is. Each indicator has a trend of increase with the loading rate reducing, and the adjustment laws of die arc transition zone equidistance profile curve are acquired for improving tube forming quality. Hence, the research results prove the feasibility of external pressure THF used for processing high-accuracy large length-to-diameter ratio metal stator screw lining, and provide theoretical basis for designing new kind of stator structure which has better performance and longer service life.

  3. [Phenotypic features in autistic individuals: the finger length ratio (2D:4D), hair whorl, and hand dominance].

    Science.gov (United States)

    Aksu, Funda; Baykara, Burak; Ergın, Canem; Arman, Candan

    2013-01-01

    The aim of this study was to compare the finger length ratio (2D:4D), hair whorl direction, and hand, foot, and eye dominance in autistic and healthy individuals, and to investigate the phenotypic characteristics of autism. The study included 37 males diagnosed with autistic disorder and 121 healthy males, all aged 4-18 years. The length of the index and ring fingers of both hands--from the proximal bend of the metacarpophalangeal joint to the fingertips--was measured with digital calipers and the index-ring finger (2D:4D) ratio was determined. The distance between hair whorls, their perpendicular distance from the mid-sagittal line, and their direction of rotation were calculated in the autism and control groups. Hand, foot, and eye dominance were determined in both groups. The findings were evaluated using SPSS v.15.0. The autism group had a greater number of hair whorls than the control group. The distance between hair whorls and the mid-sagittal line was longer in those with left hand and left eye dominance. A significant difference in the 2D:4D ratio of the right and left hands between the 2 groups was not observed. The autism group had more hair whorls than the control group and the hair whorls in the autistic individuals with left hand and left eye dominance were located further from the mid-saggital line. We think that these novel findings might contribute to the determination of the phenotypic features specific to autism.

  4. Cycle length and COD/N ratio determine properties of aerobic granules treating high-nitrogen wastewater.

    Science.gov (United States)

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

    2014-07-01

    Aerobic granule characteristic in sequencing batch reactors treating high-nitrogen digester supernatant was investigated at cycle lengths (t) of 6, 8 and 12 h with the COD/N ratios in the influent of 4.5 and 2.3. The biomass production (Y obs) correlated with the extracellular polymeric substances (EPS) in grams per COD removed. Denitrification efficiency significantly decreased as the amount of EPS in biomass increased, suggesting that organic assimilation in EPS hampers nitrogen removal. Granule hydrophobicity was highest at t of 8 h; the t has to be long enough to remove pollutants, but not so long that excessive biomass starvation causes extracellular protein consumption that decreases hydrophobicity. At a given t, reducing the COD/N ratio improved hydrophobicity that stimulates cell aggregation. At t of 6 h and the COD/N ratio of 2.3, the dominance of 0.5-1.0 mm granules favored simultaneous nitrification and denitrification and resulted in the highest nitrogen removal.

  5. Length-Weight Relationships, Condition Index and Sex Ratio of Mussel Lamellidens corrianus (Lea, 1834 in a Freshwater Lake, Northwest Bangladesh

    Directory of Open Access Journals (Sweden)

    Mondol Mostafizur Rahman

    2016-12-01

    Full Text Available Allometry, condition index and sex ratio in freshwater mussel Lamellidens corrianus (Lea, 1834 were studied from the freshwater lake at Rajshahi, Northwest Bangladesh during the summer 2013. The collected mussel specimens ranged from 3.69 cm to 9.98 cm in length, and 4.82 g to 80.67 g in weight. The study was focused on the relationships between length-height and length-weights (length-total weight, length-tissue wet weight, length-shell wet weight, length-tissue dry weight and length-shell dry weight, which were found not to be significantly different between male and female (P<0.05. The calculated regression equation of length-height relationship for the entire study period was H= 0.5215L-0.1482 for combined sex. The equations of length-total weight, length-tissue wet weight, length-shell weight, length-tissue dry weight and length-shell dry weight relationships of mussel were W= 0.1756L2.6775, W= 0.0261L2.8919, W= 0.0261L2.5524, W= 0.0065L2.8946 and W= 0.095L2.5109, respectively for combined sex. The relationships between length and height were linear, while that between length-weights follow the non-linear pattern. The overall male to female sex ratio was 1: 0.92 and did not differ significantly from the expected 1: 1 ratio (x2-test, P<0.05. The condition index for male, female and combined sex was 13.54, 13.97 and 13.74, respectively. The results of this study will provide baseline information for fisheries researchers and for the further assessment and management of mussels in the freshwater ecosystems of Bangladesh.

  6. Biological markers of asexuality: Handedness, birth order, and finger length ratios in self-identified asexual men and women.

    Science.gov (United States)

    Yule, Morag A; Brotto, Lori A; Gorzalka, Boris B

    2014-02-01

    Human asexuality is defined as a lack of sexual attraction to anyone or anything and it has been suggested that it may be best conceptualized as a sexual orientation. Non-right-handedness, fraternal birth order, and finger length ratio (2D:4D) are early neurodevelopmental markers associated with sexual orientation. We conducted an Internet study investigating the relationship between self-identification as asexual, handedness, number of older siblings, and self-measured finger-lengths in comparison to individuals of other sexual orientation groups. A total of 325 asexuals (60 men and 265 women; M age, 24.8 years), 690 heterosexuals (190 men and 500 women; M age, 23.5 years), and 268 non-heterosexuals (homosexual and bisexual; 64 men and 204 women; M age, 29.0 years) completed online questionnaires. Asexual men and women were 2.4 and 2.5 times, respectively, more likely to be non-right-handed than their heterosexual counterparts and there were significant differences between sexual orientation groups in number of older brothers and older sisters, and this depended on handedness. Asexual and non-heterosexual men were more likely to be later-born than heterosexual men, and asexual women were more likely to be earlier-born than non-heterosexual women. We found no significant differences between sexual orientation groups on measurements of 2D:4D ratio. This is one of the first studies to test and provide preliminary empirical support for an underlying neurodevelopmental basis to account for the lack of sexual attraction characteristic of asexuality.

  7. Role of the ratio of biopolyelectrolyte persistence length to nanoparticle size in the structural tuning of electrostatic complexes

    Science.gov (United States)

    Shi, Li; Carn, Florent; Boué, François; Buhler, Eric

    2016-09-01

    Aggregation of nanoparticles of given size R induced by addition of a polymer strongly depends on its degree of rigidity. This is shown here on a large variety of silica nanoparticle self-assemblies obtained by electrostatic complexation with carefully selected oppositely charged biopolyelectrolytes of different rigidity. The effective rigidity is quantified by the total persistence length LT representing the sum of the intrinsic (Lp) and electrostatic (Le) polyelectrolyte persistence length, which depends on the screening, i.e., on ionic strength due to counterions and external salt concentrations. We experimentally show that the ratio LT/R is the main tuning parameter that controls the fractal dimension Df of the nanoparticles' self-assemblies, which is determined using small-angle neutron scattering: (i) For LT/R nanoparticles in excess, hence ramified structures with Df˜2 . (ii) For 0.3 chitosan or hyaluronan complexes), chain stiffness promotes the formation of one-dimensional nanorods (in excess of nanoparticles), in good agreement with computer simulations. (iii) For LT/R >1 ,Le is strongly increased due to the absence of salt and repulsions between nanoparticles cannot be compensated for by the polyelectrolyte wrapping, which allows a spacing between nanoparticles and the formation of one-dimensional pearl necklace complexes. (iv) Finally, electrostatic screening, i.e., ionic strength, turned out to be a reliable way of controlling Df and the phase diagram behavior. It finely tunes the short-range interparticle potential, resulting in larger fractal dimensions at higher ionic strength.

  8. Copolymers of N-cyclohexylacrylamide and n-butyl acrylate: synthesis, characterization, monomer reactivity ratios and mean sequence length

    Directory of Open Access Journals (Sweden)

    2007-06-01

    Full Text Available Copolymerization of N-cyclohexylacrylamide (NCHA and n-butyl acrylate (BA was carried out in dimethylformamide at 55±1°C using azobisisobutyronitrile as a free radical initiator. The copolymers were characterized by 1H-NMR spectroscopy and the copolymer compositions were determined by 1H-NMR analysis. The reactivity ratios of the monomers were determined by both linear and non-linear methods. The reactivity ratios of monomers determined using linear methods like Fineman-Ross (r1 = 0.37 and r2 = 1.77 , Kelen-Tudos (r1 = 0.38 and r2 = 1.77, ext. Kelen-Tudos (r1 = 0.37 and r2 = 1.75 Yezrieler-Brokhina-Roskin (r1 = 0.37 and r2 = 1.77 and non-linear methods like Tidwell-Mortimer (r1 = 0.37 and r2 = 1.76, ProCop (r1 = 0.36 and r2 = 1.82. The Q and e values for NCHA are 0.67 and 0.68 respectively. Mean sequence lengths of copolymers are estimated from r1 and r2 values. It shows that the BA units increases in a linear fashion in the polymer chain as the concentration of BA increases in the monomer feed.

  9. Failure-to-success ratios, transition probabilities and phase lengths for prophylactic vaccines versus other pharmaceuticals in the development pipeline.

    Science.gov (United States)

    Davis, Matthew M; Butchart, Amy T; Wheeler, John R C; Coleman, Margaret S; Singer, Dianne C; Freed, Gary L

    2011-11-28

    Research and development of prophylactic vaccines carries a high risk of failure. In the past, industry experts have asserted that vaccines are riskier to produce than other pharmaceuticals. This assertion has not been critically examined. We assessed outcomes in pharmaceutical research and development from 1995 to 2011, using a global pharmaceutical database to identify prophylactic vaccines versus other pharmaceuticals in preclinical, Phase I, Phase II, or Phase III stages of development. Over 16 years of follow-up for 4367 products (132 prophylactic vaccines; 4235 other pharmaceuticals), we determined the failure-to-success ratios for prophylactic vaccines versus all other products. The overall ratio of failures to successes for prophylactic vaccines for the 1995 cohort over 16 years of follow-up was 8.3 (116/14) versus 7.7 (3650/475) for other pharmaceuticals. The probability of advancing through the development pipeline at each point was not significantly different for prophylactic vaccines than for other pharmaceuticals. Phase length was significantly longer for prophylactic vaccines than other pharmaceuticals for preclinical development (3.70 years vs 2.80 years; pvaccines are not significantly different from those of other pharmaceutical products, which may partially explain rapidly growing interest in prophylactic vaccines among major pharmaceutical manufacturers.

  10. Time to achieving therapeutic international normalized ratio increases hospital length of stay after heart valve replacement surgery.

    Science.gov (United States)

    Arendt, Christopher J; Hong, Joon Hwa; Daly, Richard C; Scott, Christopher; Mehta, Ramila A; Bailey, Kent; Pathak, Jyotishman; Pereira, Naveen L

    2017-05-01

    Achieving a therapeutic international normalized ratio (INR) before hospital discharge is an important inpatient goal for patients undergoing mechanical cardiac valve replacement (MCVR). The use of clinical algorithms has reduced the time to achieve therapeutic INR (TTI) with warfarin therapy. Whether TTI prolongs length of stay (LOS) is unknown. Patients who underwent MCVR over a consecutive 42-month period were included. Clinical data were obtained from the Society of Thoracic Surgeons Adult Cardiac Surgery database and electronic medical records. Therapeutic INR was defined as per standard guidelines. Warfarin dose was prescribed using an inpatient pharmacy-managed algorithm and computer-based dosing tool. International normalized ratio trajectory, procedural needs, and drug interactions were included in warfarin dose determination. There were 708 patients who underwent MCVR, of which 159 were excluded for reasons that would preclude or interrupt warfarin use. Among the remainder of 549 patients, the average LOS was 6.4days and mean TTI was 3.5days. Landmark analysis showed that subjects in hospital on day 4 (n=542) who achieved therapeutic INR were more likely to be discharged by day 6 compared with those who did not achieve therapeutic INR (75% vs 59%, P<.001). Multivariable proportional hazards regression with TTI as a time-dependent effect showed a strong association with discharge (P=.0096, hazard ratio1.3) after adjustment for other significant clinical covariates. Time to achieve therapeutic INR is an independent predictor of LOS in patients requiring anticoagulation with warfarin after MCVR surgery. Alternative dosing and anticoagulation strategies will need to be adopted to reduce LOS in these patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Contraction dynamics and function of the muscle-tendon complex depend on the muscle fibre-tendon length ratio: a simulation study.

    Science.gov (United States)

    Mörl, Falk; Siebert, Tobias; Häufle, Daniel

    2016-02-01

    Experimental studies show different muscle-tendon complex (MTC) functions (e.g. motor or spring) depending on the muscle fibre-tendon length ratio. Comparing different MTC of different animals examined experimentally, the extracted MTC functions are biased by, for example, MTC-specific pennation angle and fibre-type distribution or divergent experimental protocols (e.g. influence of temperature or stimulation on MTC force). Thus, a thorough understanding of variation of these inner muscle fibre-tendon length ratios on MTC function is difficult. In this study, we used a hill-type muscle model to simulate MTC. The model consists of a contractile element (CE) simulating muscle fibres, a serial element (SE) as a model for tendon, and a parallel elastic element (PEE) modelling tissue in parallel to the muscle fibres. The simulation examines the impact of length variations of these components on contraction dynamics and MTC function. Ensuring a constant overall length of the MTC by L(MTC) = L(SE) + L(CE), the SE rest length was varied over a broad physiological range from 0.1 to 0.9 MTC length. Five different MTC functions were investigated by simulating typical physiological experiments: the stabilising function with isometric contractions, the motor function with contractions against a weight, the capability of acceleration with contractions against a small inertial mass, the braking function by decelerating a mass, and the spring function with stretch-shortening cycles. The ratio of SE and CE mainly determines the MTC function. MTC with comparably short tendon generates high force and maximal shortening velocity and is able to produce maximal work and power. MTC with long tendon is suitable to store and release a maximum amount of energy. Variation of muscle fibre-tendon ratio yielded two peaks for MTC's force response for short and long SE lengths. Further, maximum work storage capacity of the SE is at long relL(SE,0). Impact of fibre-tendon length ratio on MTC

  12. Differences in finger length ratio between males with autism, pervasive developmental disorder-not otherwise specified, ADHD, and anxiety disorders

    NARCIS (Netherlands)

    de Bruin, Esther I.; Verheij, Fop; Wiegman, T.; Ferdinand, Robert F.

    2006-01-01

    Children with autism have a relatively shorter index finger (2D) compared with their ring finger (4D). It is often presumed that the 2D:4D ratio is associated with fetal testosterone levels and that high fetal testosterone levels could play a role in the aetiology of autism. It is unknown whether th

  13. Association of newborn diseases with weight/length ratio and the adequacy of weight for gestational age

    Directory of Open Access Journals (Sweden)

    José Ricardo Dias Bertagnon

    2011-09-01

    Full Text Available Objective: To compare the frequencies of newborn diseases in thosenewborns classified according to a weight/length rate and thoseclassified by the adequacy weight for gestational age. Methods: Aretrospective cross-sectional study by record assessment was carriedout enclosing all the live newborns at Hospital Geral do Grajaú, fromSeptember to December, 2009 (n =577 classified according to therate weight/length and also to the adequacy weight for gestationalage. The 10 and 90 percentiles of the weight/length distribution, nowdesignated as “indices” were calculated leading to the followingclassification: low index, for newborns below 54.8 g/cm; high index,for those over 75.8 g/cm; and average index, for the remainingnewborns. According to the adequacy weight for gestational age thenewborns were designated as pre-term for gestational age; term smallfor gestational age; appropriate term and large term. In this samplethere were no small and large pre-term or post-term newborns. Majordiseases were related to the index and adequacy extracts by the χ2test for a contingency table. Results: A significant association wasfound among low index, pre-term for gestational age newborns andterm small for gestational age; between average index and appropriatefor gestational age term newborns; and high index with large termappropriate for gestational age newborns (p< 0.001. Hypoglycemia(3.4% was associated to both low and high indices, to appropriatefor gestational age preterm newborns and to small for gestational ageterm newborns. Sepsis (3.1% was associated to both low index andpre-term appropriate for gestational age newborns. The respiratorydistress syndrome (1.3% was associated to low index and pre-termappropriate for gestational age newborns. Other respiratory distresssyndromes (3.8% were associated to low and high indices but notto the adequacy for gestational age classification. Jaundice (14.9%was not associated to the studied classifications

  14. Experimental investigation of the effects of length to diameter ratio and nozzle number on the performance of counter flow Ranque-Hilsch vortex tubes

    Science.gov (United States)

    Dincer, K.; Baskaya, S.; Uysal, B. Z.

    2008-01-01

    In this experimental study, performance of counter flow type Ranque-Hilsch vortex tubes (RHVT), with a length to diameter ratio of 10, 15 and 18, were investigated with 2, 4, 6 nozzles. The measure of performance was chosen as the difference between the temperatures of hot output stream and cold output stream. The performances of RHVTs were experimentally tested by making use of velocity and temperature measurements of the input and output streams. It was determined that the difference between the temperatures of these streams, changed between 9 and 56 K. When all the results were assessed, it was concluded that the best performance was obtained when the ratio of vortex tube’s length to the diameter was 15 and the nozzle number was at least four, and the inlet pressure was as high as possible. Desired performance could be obtained by controlling the rate of the hot output stream.

  15. Experimental investigation of the effects of length to diameter ratio and nozzle number on the performance of counter flow Ranque-Hilsch vortex tubes

    Energy Technology Data Exchange (ETDEWEB)

    Dincer, K. [Selcuk University, Department of Mechanical Engineering, Faculty of Engineering and Architecture, Konya (Turkey); Baskaya, S. [Gazi University, Department of Mechanical Engineering, Faculty of Engineering and Architecture, Maltepe, Ankara (Turkey); Uysal, B.Z. [Gazi University, Department of Chemical Engineering, Faculty of Engineering and Architecture, Maltepe, Ankara (Turkey)

    2008-01-15

    In this experimental study, performance of counter flow type Ranque-Hilsch vortex tubes (RHVT), with a length to diameter ratio of 10, 15 and 18, were investigated with 2, 4, 6 nozzles. The measure of performance was chosen as the difference between the temperatures of hot output stream and cold output stream. The performances of RHVTs were experimentally tested by making use of velocity and temperature measurements of the input and output streams. It was determined that the difference between the temperatures of these streams, changed between 9 and 56 K. When all the results were assessed, it was concluded that the best performance was obtained when the ratio of vortex tube's length to the diameter was 15 and the nozzle number was at least four, and the inlet pressure was as high as possible. Desired performance could be obtained by controlling the rate of the hot output stream. (orig.)

  16. Differences in finger length ratio between males with autism, pervasive developmental disorder-not otherwise specified, ADHD, and anxiety disorders.

    Science.gov (United States)

    de Bruin, Esther I; Verheij, Fop; Wiegman, T; Ferdinand, Robert F

    2006-12-01

    Children with autism have a relatively shorter index finger (2D) compared with their ring finger (4D). It is often presumed that the 2D:4D ratio is associated with fetal testosterone levels and that high fetal testosterone levels could play a role in the aetiology of autism. It is unknown whether this effect is specific to autism. In this study, 2D:4D ratios of 144 males aged 6 to 14 years (mean age 9y 1 mo [SD 1y 11 mo]) with psychiatric disorders were compared with those of 96 males aged 6 to 13 years from the general population (mean age 9y 1 mo [SD 1y 10 mo]). Psychiatric disorders were divided into autism/Asperger syndrome (n=24), pervasive developmental disorder-not otherwise specified (PDD-NOS; n=26), attention-deficit-hyperactivity disorder (ADHD)/oppositional defiant disorder (ODD; n=68), and anxiety disorders (n=26). Males with autism/Asperger syndrome (pADHD/ODD (pAsperger syndrome had lower ratios than those in the comparison group. These results indicated that higher fetal testosterone levels may play a role, not only in the origin of autism, but also in the aetiology of PDD-NOS and of ADHD/ODD. Males with anxiety disorders might have been exposed to lower prenatal testosterone levels.

  17. Cephalometric evaluation of adenoids, upper airway, maxilla, velum length, need ratio for determining velopharyngeal incompetency in subjects with unilateral cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Avinash Gohilot

    2014-01-01

    Full Text Available Objectives: Children with cleft lip and palate (CLP are seen to have reduced airway size and large adenoids, which might lead to different characteristics in the upper airway and surrounding tissues from both morphological and functional perspectives. Decrease in adenoid size and increase in need ratio in cleft patients might lead to velopharyngeal incompetency (VPI and development of nasality in adulthood. No studies have been conducted on the Indian population with variables contributing to VPI. So the aim was to evaluate the size and position of the adenoids, upper airway, maxilla, velum length and need ratio contributing to VPI in subjects with and without unilateral cleft lip and palate (UCLP during juvenile and adolescent stages. Materials and Methods: Cephalograms of 120 subjects with 6-17 years were taken and various linear and angular measurements were measured and data was analyzed using the unpaired t test. Results: Adenoids were significantly larger and the upper airway smaller in the juvenile and adolescent cleft group than in the non-cleft group. In the adolescent cleft group, airway was larger than that in the adolescent non-cleft group. The maxilla was small and retropositioned in juvenile and adolescent subjects as compared to non cleft cases. Length of velum was smaller and need ratio was larger in both juvenile and adolescent groups as compared to the non-cleft group, suggestive of velopharyngeal incompetence. Conclusion: Decreased Adenoids, restricted airway, small, retruded maxilla, smaller velum length and larger need ratio larger were seen in the cleft group as compared to the non-cleft group, which was suggestive of VPI.

  18. Changes of Root Length and Root-to-Crown Ratio after Apical Surgery: An Analysis by Using Cone-beam Computed Tomography.

    Science.gov (United States)

    von Arx, Thomas; Jensen, Simon S; Bornstein, Michael M

    2015-09-01

    Apical surgery is an important treatment option for teeth with post-treatment periodontitis. Although apical surgery involves root-end resection, no morphometric data are yet available about root-end resection and its impact on the root-to-crown ratio (RCR). The present study assessed the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47 patients) were measured before and after apical surgery. Data were collected relative to the cementoenamel junction (CEJ) as well as to the crestal bone level (CBL). One observer took all measurements twice (to calculate the intraobserver variability), and the means were used for further analysis. The following parameters were assessed for all treated teeth as well as for specific tooth groups: length of root-end resection and percentage change of root length, preoperative and postoperative RCRs, and percentage change of RCR after apical surgery. The mean length of root-end resection was 3.58 ± 1.43 mm (relative to the CBL). This amounted to a loss of 33.2% of clinical and 26% of anatomic root length. There was an overall significant difference between the tooth groups (P < .05). There was also a statistically significant difference comparing mandibular and maxillary teeth (P < .05), but not for incisors/canines versus premolars/molars (P = .125). The mean preoperative and postoperative RCRs (relative to CEJ) were 1.83 and 1.35, respectively (P < .001). With regard to the CBL reference, the mean preoperative and postoperative RCRs were 1.08 and 0.71 (CBL), respectively (P < .001). The calculated changes of RCR after apical surgery were 24.8% relative to CEJ and 33.3% relative to CBL (P < .001). Across the different tooth groups, the mean RCR was not significantly different (P = .244 for

  19. The influence of gamete co-incubation length on the in vitro fertility and sex ratio of bovine bulls with different penetration speed.

    Science.gov (United States)

    Sattar, A; Rubessa, M; Di Francesco, S; Longobardi, V; Di Palo, R; Zicarelli, L; Campanile, G; Gasparrini, B

    2011-12-01

    The objectives of this work were to evaluate whether the sperm penetration speed is correlated to the in vitro fertility and whether adapting the gamete co-incubation length to the kinetics of the bull improves in vitro fertility and affects the sex ratio. In vitro matured oocytes were co-incubated with spermatozoa from four different bulls (A-D). At various post-insemination (p.i.) times (4, 8, 12, 16 and 20 h), samples of oocytes were fixed and stained with DAPI for nuclei examination, while the remaining ones were transferred into culture to evaluate embryo development. The blastocysts produced were sexed by PCR. Two bulls (A and B) had faster kinetics than the others (C and D), as shown by the higher penetration rates recorded at 4 h p.i. (43%, 30%, 11% and 6%, respectively for bulls A, B, C and D; pbulls did not reflect their in vitro fertility. The incidence of polyspermy was higher for faster penetrating bulls (36%, 24%, 16% and 4%, respectively for bulls A, B, C and D; pbulls may be improved by adapting the co-incubation length to their penetration speed. A sperm-oocyte co-incubation length of 8 h ensured the greatest blastocyst yields for the two faster penetrating bulls. On the contrary, 16 h co-incubation was required to increase (pbulls. Bulls with a faster kinetics did not alter the embryo sex ratio towards males. The female/male (F/M) ratios recorded were 2.1, 1.4, 1.2, 1.3 and 1.6, respectively at 4, 8, 12, 16 and 20 h p.i.

  20. Effect of variation of length-to-depth ratio and Mach number on the performance of a typical double cavity scramjet combustor

    Science.gov (United States)

    Mahto, Navin Kumar; Choubey, Gautam; Suneetha, Lakka; Pandey, K. M.

    2016-11-01

    The two equation standard k-ɛ turbulence model and the two-dimensional compressible Reynolds-Averaged Navier-Stokes (RANS) equations have been used to computationally simulate the double cavity scramjet combustor. Here all the simulations are performed by using ANSYS 14-FLUENT code. At the same time, the validation of the present numerical simulation for double cavity has been performed by comparing its result with the available experimental data which is in accordance with the literature. The results are in good agreement with the schlieren image and the pressure distribution curve obtained experimentally. However, the pressure distribution curve obtained numerically is under-predicted in 5 locations by numerical calculation. Further, investigations on the variations of the effects of the length-to-depth ratio of cavity and Mach number on the combustion characteristics has been carried out. The present results show that there is an optimal length-to-depth ratio for the cavity for which the performance of combustor significantly improves and also efficient combustion takes place within the combustor region. Also, the shifting of the location of incident oblique shock took place in the downstream of the H2 inlet when the Mach number value increases. But after achieving a critical Mach number range of 2-2.5, the further increase in Mach number results in lower combustion efficiency which may deteriorate the performance of combustor.

  1. From neural oscillations to reasoning ability: Simulating the effect of the theta-to-gamma cycle length ratio on individual scores in a figural analogy test.

    Science.gov (United States)

    Chuderski, Adam; Andrelczyk, Krzysztof

    2015-02-01

    Several existing computational models of working memory (WM) have predicted a positive relationship (later confirmed empirically) between WM capacity and the individual ratio of theta to gamma oscillatory band lengths. These models assume that each gamma cycle represents one WM object (e.g., a binding of its features), whereas the theta cycle integrates such objects into the maintained list. As WM capacity strongly predicts reasoning, it might be expected that this ratio also predicts performance in reasoning tasks. However, no computational model has yet explained how the differences in the theta-to-gamma ratio found among adult individuals might contribute to their scores on a reasoning test. Here, we propose a novel model of how WM capacity constraints figural analogical reasoning, aimed at explaining inter-individual differences in reasoning scores in terms of the characteristics of oscillatory patterns in the brain. In the model, the gamma cycle encodes the bindings between objects/features and the roles they play in the relations processed. Asynchrony between consecutive gamma cycles results from lateral inhibition between oscillating bindings. Computer simulations showed that achieving the highest WM capacity required reaching the optimal level of inhibition. When too strong, this inhibition eliminated some bindings from WM, whereas, when inhibition was too weak, the bindings became unstable and fell apart or became improperly grouped. The model aptly replicated several empirical effects and the distribution of individual scores, as well as the patterns of correlations found in the 100-people sample attempting the same reasoning task. Most importantly, the model's reasoning performance strongly depended on its theta-to-gamma ratio in same way as the performance of human participants depended on their WM capacity. The data suggest that proper regulation of oscillations in the theta and gamma bands may be crucial for both high WM capacity and effective complex

  2. Effect of Mach number, valve angle and length to diameter ratio on thermal performance in flow of air through Ranque Hilsch vortex tube

    Science.gov (United States)

    Devade, Kiran D.; Pise, Ashok T.

    2017-01-01

    Ranque Hilsch vortex tube is a device that can produce cold and hot air streams simultaneously from pressurized air. Performance of vortex tube is influenced by a number of geometrical and operational parameters. In this study parametric analysis of vortex tube is carried out. Air is used as the working fluid and geometrical parameters like length to diameter ratio (15, 16, 17, 18), exit valve angles (30°-90°), orifice diameters (5, 6 and 7 mm), 2 entry nozzles and tube divergence angle 4° is used for experimentation. Operational parameters like pressure (200-600 kPa), cold mass fraction (0-1) is varied and effect of Mach number at the inlet of the tube is investigated. The vortex tube is tested at sub sonic (0 tube is observed for CMF up to 0.5. Experimental correlations are proposed for optimum COP. Parametric correlation is developed for geometrical and operational parameters.

  3. The high cost of hospital trauma care: an analysis of hospital length of stay, injury severity score, case mix index, and reimbursement-to-cost ratio.

    Science.gov (United States)

    Legorreta, A P; Mikos, J; Sullivan, A; Delany, H M

    1993-01-01

    We conducted a study to evaluate reimbursement characteristics for an urban hospital providing a high volume of trauma care. Complete clinical and financial data for 209 trauma patients admitted to the Bronx Municipal Hospital Center during September 1990 were entered into a trauma registry. Patients were categorized into three groups. Group 1 fulfilled criteria for reimbursement using the New York State Major Diagnostic Category 25 (NYSMDC 25) for trauma. Group 2 patients fulfilled New York City Emergency Medical Service 911 criteria for transport to a level 1 trauma center. Group 3 patients did not fit either category. Analysis included age, race, sex, length of stay, injury severity score, case mix index, payer source, and reimbursement-to-cost ratio. Of the patients studied, 77.5% were men. Hispanic, African-American, and white patients constituted 40.2%, 26.3%, and 17.2%, respectively, of the study population. The payer mix was 36.6% Medicaid; 20.8% self-pay; 19.1% no fault; 9.6% Blue Cross; 5.5% Medicare; 5% commercial; and 3.3% other. The study demonstrated that criteria for group 1 and group 2 define patients who constitute a distinct clinical group by injury severity score. As expected, the length of stay and case mix index were significantly higher for group 1, but they did not differ between group 2 and group 3. Group 1 was a small proportion (7.7%) of trauma patients admitted to the Bronx Municipal Hospital Center level 1 trauma center. Trauma admissions were treated at a net loss, with a projected high annual deficit of $5.3 million.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. 喷丝头长径比对PANCF原丝性能的影响%Effect of length-diameter ratio on properties of as-spun PANCF

    Institute of Scientific and Technical Information of China (English)

    王二轲; 莫迪; 陈惠芳; 潘鼎

    2009-01-01

    采用不同长径比(L/D)的陶瓷喷丝头进行湿法、干湿法纺丝制备聚丙烯腈基碳纤维(PANCF);研究了L/D对聚丙烯腈/二甲基亚砜(PAN/DMSO)纺丝原液的可纺性及原丝性能的影响.结果表明:随着喷丝头L/D的增大,PAN/DMSO纺丝原液的可纺性提高,PANCF原丝的膨润度逐渐减少,PANCF原丝的结晶度、取向度及强度随之增大,有利于提高纤维的性能.%Ceramic spinnerets with different length-diameter ratio ( L/D ) were used to produce polyacrylonitrile-based carbon fiber (PANCF)via wet spinning process or dry-wet spinning process.The effect of L/D on the spinnability of polyacrylonitrile/ dimethyl sulphoxide (PAN/DMSO) spinning solution and the properties of as-spun fiber was studied.The results showed that the spinnability of PAN/DMSO spinning solution was increased,the swelling degree of PANCF was gradually decreased,the crystal-linity,orientation and strength of PANCF were increased as the spinneret L/D was increased.

  5. Effects of prenatal Leydig cell function on the ratio of the second to fourth digit lengths in school-aged children.

    Directory of Open Access Journals (Sweden)

    Takahiko Mitsui

    Full Text Available Prenatal sex hormones can induce abnormalities in the reproductive system and adversely impact on genital development. We investigated whether sex hormones in cord blood influenced the ratio of the second to fourth digit lengths (2D/4D in school-aged children. Of the 514 children who participated in a prospective cohort study on birth in Sapporo between 2002 and 2005, the following sex hormone levels were measured in 294 stored cord blood samples (135 boys and 159 girls; testosterone (T, estradiol (E, progesterone, LH, FSH, inhibin B, and insulin-like factor 3 (INSL3. A total of 350 children, who were of school age and could be contacted for this survey, were then requested via mail to send black-and-white photocopies of the palms of both the left and right hands. 2D/4D was calculated in 190 children (88 boys and 102 girls using photocopies and derived from participants with the characteristics of older mothers, a higher annual household income, higher educational level, and fewer smokers among family members. 2D/4D was significantly lower in males than in females (p<0.01. In the 294 stored cord blood samples, T, T/E, LH, FSH, Inhibin B, and INSL3 levels were significantly higher in samples collected from males than those from females. A multivariate regression model revealed that 2D/4D negatively correlated with INSL3 in males and was significantly higher in males with <0.32 ng/mL of INSL3 (p<0.01. No correlations were observed between other hormones and 2D/4D. In conclusion, 2D/4D in school-aged children, which was significantly lower in males than in females, was affected by prenatal Leydig cell function.

  6. Maternal corticosterone but not testosterone level is associated with the ratio of second-to-fourth digit length (2D:4D) in field vole offspring (Microtus agrestis).

    Science.gov (United States)

    Lilley, Thomas; Laaksonen, Toni; Huitu, Otso; Helle, Samuli

    2010-03-30

    The steroid environment encountered by a foetus can strongly affect its post-natal physiology and behaviour. It has been proposed that steroid concentrations experienced in utero could be estimated from adults by measuring their second-to-fourth digit length ratio (2D:4D). However, there is still little direct evidence that intra-uterine steroid levels affect individual 2D:4D. We examined whether maternal pre-pregnancy testosterone and corticosterone levels (as estimates of intra-uterine testosterone and corticosterone exposure) affected the 2D:4D of pups in non-domesticated field voles (Microtus agrestis), measured by X-rays at the age of weaning (21 days). Furthermore, for the first time in a non-human species, we studied whether testosterone and corticosterone levels correlated with 2D:4D in adult females. We found that the maternal pre-pregnancy level of testosterone was not associated with offspring 2D:4D in either the left or the right paw. Instead, maternal pre-pregnancy corticosterone level was positively correlated with offspring 2D:4D in the right paw, but unrelated to 2D:4D in the left paw. In addition, the 2D:4D of adult females was not associated with either their circulating testosterone or corticosterone levels. Our results suggest that in field voles maternally administered testosterone is not a major determinant of offspring 2D:4D, whereas maternal stress appears to account for some of the variation in the 2D:4D of their offspring.

  7. Corepressor effect on androgen receptor activity varies with the length of the CAG encoded polyglutamine repeat and is dependent on receptor/corepressor ratio in prostate cancer cells.

    Science.gov (United States)

    Buchanan, Grant; Need, Eleanor F; Barrett, Jeffrey M; Bianco-Miotto, Tina; Thompson, Vanessa C; Butler, Lisa M; Marshall, Villis R; Tilley, Wayne D; Coetzee, Gerhard A

    2011-08-01

    The response of prostate cells to androgens reflects a combination of androgen receptor (AR) transactivation and transrepression, but how these two processes differ mechanistically and influence prostate cancer risk and disease outcome remain elusive. Given recent interest in targeting AR transrepressive processes, a better understanding of AR/corepressor interaction and responses is warranted. Here, we used transactivation and interaction assays with wild-type and mutant ARs, and deletion AR fragments, to dissect the relationship between AR and the corepressor, silencing mediator for retinoic acid and thyroid hormone receptors (SMRT). We additionally tested how these processes are influenced by AR agonist and antagonist ligands, as well as by variation in the polyglutamine tract in the AR amino terminal domain (NTD), which is encoded by a polymorphic CAG repeat in the gene. SMRT was recruited to the AR ligand binding domain by agonist ligand, and as determined by the effect of strategic mutations in activation function 2 (AF-2), requires a precise conformation of that domain. A distinct region of SMRT also mediated interaction with the AR-NTD via the transactivation unit 5 (TAU5; residues 315-538) region. The degree to which SMRT was able to repress AR increased from 17% to 56% as the AR polyglutamine repeat length was increased from 9 to 42 residues, but critically this effect could be abolished by increasing the SMRT:AR molar ratio. These data suggest that the extent to which the CAG encoded polyglutamine repeat influences AR activity represents a balance between corepressor and coactivator occupancy of the same ligand-dependent and independent AR interaction surfaces. Changes in the homeostatic relationship of AR to these molecules, including SMRT, may explain the variable penetrance of the CAG repeat and the loss of AR signaling flexibility in prostate cancer progression.

  8. Simple biodosimetry method for cases of high-dose radiation exposure using the ratio of the longest/shortest length of Giemsa-stained drug-induced prematurely condensed chromosomes (PCC).

    Science.gov (United States)

    Gotoh, E; Tanno, Y

    2005-05-01

    The aim was to develop a simple biodosimetry method for as rapid as possible estimation of absorbed radiation doses in victims of radiation accidents, in particular after high-dose exposure. Human peripheral blood lymphocytes (PBL) were gamma-irradiated in vitro with several doses up to 40 Gy stimulated with phytohaemagglutinin-P (PHA-P) for 2 days and their chromosomes condensed prematurely using 50 nm calyculin A. Chromosome lengths of Giemsa-stained G2 prematurely condensed chromosomes (PCC) were measured using image analysing software and the ratio of the longest/shortest chromosome length was calculated. The length ratio (LR) of the longest/shortest Giemsa-stained chromosome s increased with a good correlation to the square root of the radiation dose (D) up to 40 Gy, i.e. LR = (4.90 x D0.5) + 2.14. The LR of the longest/shortest chromosome might be used as an index for estimating the radiation dose. The blood samples should not be cooled until the start of separation/stimulation of the lymphocytes. A rapid and easy estimation of large doses after whole-body exposure was identified by measuring the ratio of the longest/shortest length of Giemsa-stained G2-PCC induced by calyculin A. This simple protocol will be particularly useful for making therapy decisions for victims of ionizing radiation exposure and has potential for use as a biodosimeter for partial-body exposure accidents.

  9. Cation ratio fluctuations in Cu2ZnSnS4 at the 20 nm length scale investigated by analytical electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A. [National Renewable Energy Laboratory, Golden CO 80401 USA; Erkan, Mehmet E. [Department of Electrical and Computer Engineering, University of Utah, UT 84112 USA; Pruzan, Dennis S. [Department of Materials Science and Engineering, University of Utah, UT 84112 USA; Nagaoka, Akira [Department of Materials Science and Engineering, University of Utah, UT 84112 USA; Department of Applied Physics and Electronic Engineering, University of Miyazaki, Miyazaki 889 2192 Japan; Yoshino, Kenji [Department of Applied Physics and Electronic Engineering, University of Miyazaki, Miyazaki 889 2192 Japan; Moutinho, Helio [National Renewable Energy Laboratory, Golden CO 80401 USA; Al-Jassim, Mowafak [National Renewable Energy Laboratory, Golden CO 80401 USA; Scarpulla, Michael A. [Department of Electrical and Computer Engineering, University of Utah, UT 84112 USA; Department of Materials Science and Engineering, University of Utah, UT 84112 USA

    2016-04-05

    Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) is a sustainable material for thin-film photovoltaics with device efficiencies greater than 12% have been demonstrated. Despite similar crystal structure and polycrystalline film microstructures, there is widespread evidence for larger-amplitude potential and bandgap fluctuations in CZTS than in the analogous Cu(In,Ga)Se2 (CIGSe) chalcopyrite material. This disorder is believed to account for a sizable part of the larger open-circuit voltage (VOC) deficit in CZTS devices, yet the detailed origins and length scales of these fluctuations have not been fully elucidated. Herein, we present a transmission electron microscopy study focusing on composition variation within bulk multicrystals of CZTS grown by the travelling heater method (THM). In these slow-cooled, solution grown crystals we find direct evidence for spatial composition fluctuations of amplitude <1 at.% (~5 x 1020 cm-3) and thus, explainable by point defects. However, rather than being homogeneously-distributed we find a characteristic 20 nm length scale for these fluctuations, which sets a definite length scale for band gap and potential fluctuations. At Σ3 grain boundaries, we find no evidence of composition variation compared to the bulk. The finding highlights such variations reported at grain boundaries in polycrystalline thin-films are direct consequences of processing methods and not intrinsic properties of CZTS itself.

  10. Plastic Models Designed to Produce Large Height-to-Length Ratio Steady-State Planar and Axisymmetric (Radial) Viscous Liquid Laminar Flow Gravity Currents

    Science.gov (United States)

    Blanck, Harvey F.

    2012-01-01

    Naturally occurring gravity currents include events such as air flowing through an open front door, a volcanic eruption's pyroclastic flow down a mountainside, and the spread of the Bhopal disaster's methyl isocyanate gas. Gravity currents typically have a small height-to-distance ratio. Plastic models were designed and constructed with a…

  11. Effect of Evaporator Lengths and Ratio of Check Valves to Number of Turns on Internal Flow Patterns of a Closed-Loop Oscillating Heat-Pipe With Check Valves

    Directory of Open Access Journals (Sweden)

    S. Rittidech

    2008-01-01

    Full Text Available A visualization study of the internal flow patterns of a closed–loop oscillating heat-pipe with check valves (CLOHP/CV at normal operating condition for several evaporator lengths (Le, and ratio of check valves to number of turns (Rcv has been conducted. This article describes the effects of varying Le, and Rcv on flow patterns. The CLOHP/CV used a Pyrex glass tube with inside diameter of 2.4 mm. The evaporator length of 50 and 150 mm. (the lengths of evaporator, adiabatic and condenser were equal were employed with 10 turns, with Rcv of 0.2 and 1. R123 was used as the working fluid with filling ratio of 50% of internal volume of tube. It was found that the internal flow patterns could be classified according to the Le and Rcv as follows: At the high heat source when the Le decreases the main flow changes from the bubble flow with slug flow to disperse bubble flow. The Rcv decreases the main flow changes from the disperse bubble flow with bubble flow to disperse bubble When the velocity of slug increases, the length of vapor bubbles rapidly decreases and the heat flux rapidly increases.

  12. Fixation strength of biocomposite wedge interference screw in ACL reconstruction: effect of screw length and tunnel/screw ratio. A controlled laboratory study

    Directory of Open Access Journals (Sweden)

    Herrera Antonio

    2010-06-01

    Full Text Available Abstract Background Primary stability of the graft is essential in anterior cruciate ligament surgery. An optimal method of fixation should be easy to insert and provide great resistance against pull-out forces. A controlled laboratory study was designed to test the primary stability of ACL tendinous grafts in the tibial tunnel. The correlation between resistance to traction forces and the cross-section and length of the screw was studied. Methods The tibial phase of ACL reconstruction was performed in forty porcine tibias using digital flexor tendons of the same animal. An 8 mm tunnel was drilled in each specimen and two looped tendons placed as graft. Specimens were divided in five groups according to the diameter and length of the screw used for fixation. Wedge interference screws were used. Longitudinal traction was applied to the graft with a Servohydraulic Fatigue System. Load and displacement were controlled and analyzed. Results The mean loads to failure for each group were 295,44 N (Group 1; 9 × 23 screw, 564,05 N (Group 2; 9 × 28, 614,95 N (Group 3; 9 × 35, 651,14 N (Group 4; 10 × 28 and 664,99 (Group 5; 10 × 35. No slippage of the graft was observed in groups 3, 4 and 5. There were significant differences in the load to failure among groups (ANOVA/P Conclusions Longer and wider interference screws provide better fixation in tibial ACL graft fixation. Short screws (23 mm do not achieve optimal fixation and should be implanted only with special requirements.

  13. Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: new data and a meta-analytic review.

    Science.gov (United States)

    Hönekopp, Johannes; Bartholdt, Luise; Beier, Lothar; Liebert, Andreas

    2007-05-01

    The relative length of the second (index) to the fourth (ring) finger (2D:4D) is a putative negative correlate of prenatal testosterone (T) exposure. Therefore, 2D:4D (and to a lesser extent D(r-l), the difference between 2D:4D in the right hand and in the left hand) has often been used to study effects of prenatal androgenization on human behavior and cognition. However, evidence suggests that 2D:4D may also be related to levels of circulating sex hormones in adults. This would question the validity of 2D:4D as a means of studying the effects of prenatal sex hormones. Here we present new data from two non-clinical samples (64 women and 102 men) regarding the relationships of 2D:4D and D(r-l) with circulating sex hormone levels. We then present a meta-analytic review of all the present evidence regarding this issue. The results suggest that, in the normal population, 2D:4D and D(r-l) are not associated with adult sex hormone levels. The findings from this current study add to the growing body of evidence demonstrating that 2D:4D is a suitable tool to study the effects of prenatal androgenization on human behavior and cognition.

  14. Digit ratio (2D:4D), sex differences, allometry, and finger length of 12-30-year olds: evidence from the British Broadcasting Corporation (BBC) Internet study.

    Science.gov (United States)

    Manning, John T

    2010-01-01

    Many studies have reported digit ratio (2D:4D) to be sexually dimorphic, (males lower 2D:4D than females). However, Kratochvíl and Flegr ([2009]: Biol Lett 5:643-646) have suggested that 2D regressed on 4D has an allometric regression line with nonzero Y-intercept that is shared by males and females. Thus, 2D is shorter than expected when 4D is long, and males have lower 2D:4D than females because they have longer fingers. In this study, it is shown that this suggestion may be incorrect because sex differences in slope were not considered. Participants were recruited in an Internet study and had an age range of 12-30 years. The expected sex difference in 2D:4D was found, and the regression of 2D on 4D showed a significant sex difference in slope (males lower than females). A comparison of 10 age groups (12 years, 13 years..., 21-30 years) showed that sexual dimorphism for fingers was age dependent, varying from monomorphic to very dimorphic. Changes in sexual dimorphism of 2D:4D were much less marked, but there was a significant reduction in mean 2D:4D with age. The tendency for slopes of 2D regressed on 4D to be lower in males compared with females was significant in eight age groups. Sex difference in 2D:4D varied across the age groups and was positively related to the magnitude of the difference in female and male slopes. In contrast to the report of Kratochvíl and Flegr, it was found that the regression of 2D on 4D showed sex differences in slope, and such differences gave rise to the sexual dimorphism in 2D:4D.

  15. Association of second to fourth digit length ratio (2D:4D with some anthropometric measurements: a comparison between Polish and Indian young adults aged 18-25 years

    Directory of Open Access Journals (Sweden)

    R. Chakraborty

    2015-07-01

    Full Text Available Background: The ratio of lengths of second to the fourth digit (2D:4D is a proxy indicator of prenatal sex-hormone exposure. The male has lower 2D:4D than the female. The ratio and its sexual dimorphism vary across ethnicity. The relationships of 2D:4D with anthropometric dimensions are not consistent. Objective: To compare 2D:4D and its sexual dimorphism between the young Indian and Polish populations and to examine the relationship between 2D:4D and anthropometric measures. Methods: This cross-sectional study included 152 Indian (males: 71 females: 81 and 110 Polish (55 each sex young adults aged between 18 and 25 years. Height, weight, waist and hip circumferences, second and fourth digit lengths were measured. Results: Males had significantly lower 2D:4D than the female in both hands in both the ethnic groups. All the anthropometric measurements were higher in Polish males, including the 2D:4D of both hands, than the Indians, except for BMI and WHR. Polish females had higher digit lengths, height, weight and HC than the Indian females. In Polish males, 2D:4D was negatively associated with height and WHR in both hands. No significant correlation was observed between any anthropometric measure (except for height and 2D:4D among the Indians. However, the Indian Female had a nearly significant positive correlation between left 2D:4D and HC. In Indian Male correlation between left hand 2D:4D and Height is significant and similar to that of the Polish men. Conclusion: It was not possible to draw any conclusion regarding the nature of association between 2D:4D and anthropometric parameters. The findings indicate a link between fat patterning and digit ratio.

  16. Measuring Thermodynamic Length

    Energy Technology Data Exchange (ETDEWEB)

    Crooks, Gavin E

    2007-09-07

    Thermodynamic length is a metric distance between equilibrium thermodynamic states. Among other interesting properties, this metric asymptotically bounds the dissipation induced by a finite time transformation of a thermodynamic system. It is also connected to the Jensen-Shannon divergence, Fisher information, and Rao's entropy differential metric. Therefore, thermodynamic length is of central interestin understanding matter out of equilibrium. In this Letter, we will consider how to denethermodynamic length for a small system described by equilibrium statistical mechanics and how to measure thermodynamic length within a computer simulation. Surprisingly, Bennett's classic acceptance ratio method for measuring free energy differences also measures thermodynamic length.

  17. Radiological examination in diagnosis of dolicho-sigmoid taking into consideration the colon and sigmoid length ratio in pediatric patients; Diagnostyka radiologiczna zespolu dlugiej esicy u dzieci ze szczegolnym uwzglednieniem wspolczynnika okrezniczo-esicznego

    Energy Technology Data Exchange (ETDEWEB)

    Bober, S.T.

    1993-12-31

    The aim of the study was usefulness evaluation of radiological examination in the diagnosis of dolicho sigmoid, especially establishing diagnosis criteria of pictures on contrast enema films which may be pathognomonic for dolicho sigmoid in children. An attempt has been made to establish objectively the length of sigmoid and colon to calculated the radio of their sizes in children with dolicho sigmoid syndrome and in control group. Contrast enemas were performed in 176 children. Among the examined children, in 26 cases dolicho sigmoid syndrome was found, including two cases of dolicho colon. Children with dolicho sigmoid syndrome showed various anomalies in elongated sigmoid location at its different levels. Generally, it was situated at the level of between L{sub 1} and L{sub 5}. The sigmoid formed often two or more abnormal loops with various bending and twisting or irregular protrusions. The coefficient or our invention concerned the ratio of colon length to the length of elongated sigmoid and on the basis of calculations made on children suffering from dolicho sigmoid syndrome the numerical values ranged from 0.7 to 1.5. The same calculations performed on the control for the proposed coefficient ranged from 2.2 to 4.2. (author). 65 refs, 15 figs, 11 tabs.

  18. Study on the digit ratio and digit length/height of soldiers in the Chinese people's armed tactical unit%武警某机动部队战士指长比和指长/身高的研究

    Institute of Scientific and Technical Information of China (English)

    曹亮; 周玉来; 李勇; 陈志忠; 雷晴

    2014-01-01

    目的:探讨武警部队战士指长比和指长/身高的特点,旨在获得军队此方面体质人类学数据,并为军队科学训练、安全管理提供理论依据。方法对武警某机动部队421名战士测量身高及左右4个手指长度,将指长与军标比较,计算指长比和指长/身高,并与年龄和文化程度进行相关分析。结果①该机动部队战士左右手指长大小关系均为3D>4D>2D>5D。左手2D、3D和右手的2D、5D均较军标长。左手和右手的指长比大小关系均为3D∶5D>4D∶5D>2D∶5D>3D∶4D>2D∶4D>2D∶3D;指长/身高大小关系均为3D∶H>4D∶H>2D∶H>5D∶H。②左手的2D∶4D、3D∶4D、右手的2D∶3D与年龄呈正相关。右手的3D∶4D及3D∶5D与年龄均呈负相关。指长/身高与年龄不相关。③右手的2D∶4D、3D∶4D与文化程度呈正相关,4D:H与文化程度呈负相关。结论该武警机动部队战士指长较军标长,年龄、文化程度与指长比、指长/身高具有部分较弱的相关性。本研究获得了部队指长比和指长/身高的体质人类学数据,并为武警部队科学训练和保持高度安全稳定提供了基础资料。%Objective To explore the traits of digit ratio and digit length/height, as to obtain the parameter of physical anthropology while to provide theoretical basis of scientific training and safety management for the army.Methods A total of 421 soldiers were measured by anthropometry technology for their heights and 4 digit lengths of two hands.Compared the digit length with the GJB. Calculated the digit ratio and digit length/height and then analysed their correlation with their age and educational level.Results ①The trend of the digit length was presented 3D>4D>2D>5D. 2D、3D of the left hand and 2D、5D of the right hand were all longer than the GJB.The digit ratio was 3D∶5D>4D∶5D>2D∶5D>3D:4D>2D∶4D>2D∶3D,and the digit length/height was 3D∶H>4D∶H>2D

  19. Flame Length

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Flame length was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  20. Minimum Length - Maximum Velocity

    CERN Document Server

    Panes, Boris

    2011-01-01

    We study a framework where the hypothesis of a minimum length in space-time is complemented with the notion of reference frame invariance. It turns out natural to interpret the action of the obtained reference frame transformations in the context of doubly special relativity. As a consequence of this formalism we find interesting connections between the minimum length properties and the modified velocity-energy relation for ultra-relativistic particles. For example we can predict the ratio between the minimum lengths in space and time using the results from OPERA about superluminal neutrinos.

  1. Normal Range of Fetal Nasal Bone Length during the Second Trimester in an Afro-Caribbean Population and Likelihood Ratio for Trisomy 21 of Absent or Hypoplastic Nasal Bone.

    Science.gov (United States)

    Gautier, Manuella; Gueneret, Michèle; Plavonil, Corinne; Jolivet, Eugénie; Schaub, Bruno

    2017-01-01

    To establish the normal reference range of fetal nasal bone length (NBL) during the second trimester in an Afro-Caribbean population and the likelihood ratio (LR) for fetal trisomy 21. Prenatal records of euploid, non-malformed singleton fetuses who underwent second-trimester ultrasonographic scans at 20-24 weeks of gestation were retrospectively analyzed for NBL and gestational age (GA). Only Afro-Caribbean couples were selected. The relationship between fetal NBL and GA was determined. The data of all fetuses with Down syndrome were provided by the French West Indies Register of Congenital Malformations (REMALAN). There was a significant linear association between fetal NBL and GA (R2 = 0. 354). The 50th percentile for NBL increased from 5.0 to 7.0 mm from week 20 to 24 of gestation. The nasal bone (NB) was absent or hypoplastic in 8.6% of the euploid fetuses and in 69.2% of the trisomy 21 fetuses. The LR for trisomy 21 of absent or hypoplastic NB in an Afro-Caribbean population was 8.02, but only 2.32 when this sign was isolated. The reference range for fetal NBL at 20-24 weeks of gestation in an Afro-Caribbean population and the LR for trisomy 21 of absent or hypoplastic NB differed from the other populations. © 2016 S. Karger AG, Basel.

  2. 光敏引发AM/DAC共聚的竞聚率测定和序列分布%Reactivity Ratio Determination and Sequence-Length Distribution of AM/DAC Copolymerization Initiated by Photosensitizer

    Institute of Scientific and Technical Information of China (English)

    李万捷; 姚婷; 郑玉刚

    2012-01-01

    The reactivity ratios of polymerization of acrylamide (AM) and 2-acryloyloxyethyl-trimethy- lammonium chloride (DAC) solution system with V-50 as photosensitizer were studied at certain condition under UV irradiation by the methods of Fineman-Ross, Kelen-Tudos and Yezrielev-Brokhina-Roskin. The results indicate that, the reactivity ratios of AM and DAC are 2. 2784 and 0. 3836 respectively at the condition of the photosensitive- initiation. The relations between molar ratio of monomers, instantaneous composition of copolymer with conversion and sequence-length distribution in the copolymers were analyzed. As a result, the technological condition of gaining relatively uniform AM/DAC copolymer is that the origination molar percentage of AM is 0.8 and the total conversion is under 80%. The copolymers were characterized by the differential scanning calorimetry. The results show that obtained polymer is copolymer of AM and DAC, not blends of two kinds of homopolymer.%以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为单体,2,2’-偶氮二异丁基脒盐酸盐(V-50)为光敏引发剂,在紫外光照射下进行水溶液聚合,采用Fineman-Ross、Kelen-Tudos及Yezrielev-Brokhina-Roskin法计算了单体竞聚率,得出光敏引发条件下,AM和DAC的竞聚率分别为2.2784和0.3836。分析了单体组成、共聚物瞬时组成随转化率变化的关系及共聚物主链的序列长度分布,得出采用AM起始物质的量比为0.8且总转化率在80%以下的合成工艺条件,可得到组成相对均一的AM/DAC共聚物。运用差示扫描量热仪对共聚物结构进行分析表征,表明所得聚合物是AM/DAC共聚物。

  3. 步宽/骨盆宽度比值和步长/骨盆厚度比值在脑瘫患儿步行康复中的作用研究%Study on the effect of the ratio of step width/pelvis width ratio and length/thickness ratio on walking rehabilitation of children with cerebral palsy

    Institute of Scientific and Technical Information of China (English)

    林国良

    2016-01-01

    目的:探讨步宽/骨盆宽度比值和步长/骨盆厚度比值在脑瘫患儿步行康复中的定量分析价值。方法选择2013年9月~2015年7月收治的脑瘫患儿50例作为研究对象,随机将其分为治疗组和对照组,各25例。均进行测量步宽/骨盆宽度和步长/骨盆厚度,治疗组以测量数据为基础,采用以跪位姿势结合踝足控制训练为主的综合康复治疗,对照组采用常规康复。步行功能评估采用粗大运动功能量表(gross motor function measure,GMFM)的E区评定,平衡能力评估采用Berg平衡功能量表(Berg balance scale,BBS)评定。结果步宽/骨盆宽度与GMFM E区评分呈高度负相关,差异有统计学意义(P<0.05);在控制步宽/骨盆宽度的影响后,步长/骨盆厚度与GMFM E区评分呈高度正相关,差异有统计学意义(P<0.05)。治疗组GMFM E区评分显著高于治疗前,差异有统计学意义(P<0.05),且显著优于对照组,差异有统计学意义(P<0.05)。结论步宽/骨盆宽度和步长/骨盆厚度在脑瘫患儿步行康复训练体系中具有良好的应用价值,值得推广。%Objective To investigate the step width/thickness of pelvis and step length/width pelvic in children with cerebral palsy rehabilitation in the quantitative analysis of the value on foot.Methods Selection of 50 cases of children with cerebral palsy were 2013.9 2015.7,were randomly divided into treatment group and control group, both for step width/thickness of the pelvis and step length/width pelvic measurement, quantitative analysis of the pelvis , adopt to kneel a pose with ankle foot control training comprehensive rehabilitation treatment method. Walking function evaluation using GMFM E zone evaluation, balance capability assessment using function of BBS. Results All children into the result analysis.Showed that the step width/pelvis width and GMFM E score is highly negative correlation(P<0.05);In

  4. Minimum length-maximum velocity

    Science.gov (United States)

    Panes, Boris

    2012-03-01

    We study a framework where the hypothesis of a minimum length in space-time is complemented with the notion of reference frame invariance. It turns out natural to interpret the action of the obtained reference frame transformations in the context of doubly special relativity. As a consequence of this formalism we find interesting connections between the minimum length properties and the modified velocity-energy relation for ultra-relativistic particles. For example, we can predict the ratio between the minimum lengths in space and time using the results from OPERA on superluminal neutrinos.

  5. Rare data on a rocky shore fish reproductive biology: sex ratio, length of first maturation and spawning period of Abudefduf saxatilis (Linnaeus, 1758 with notes on Stegastes variabilis spawning period (Perciformes: Pomacentridae in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Eduardo Bessa

    2007-09-01

    Full Text Available This study presents data on the reproduction of Abudefduf saxatilis, a rocky shore inhabitant at the northern coast of São Paulo State. A total of 73 individuals were collected using hooks and baits. They were measured, weighed and dissected, sex and maturation stage were analysed, first macroscopically, then part of the material was taken for microscopical confirmation. Visual censuses were also done for underwater observation of egg's presence. Results showed equivalence of males and females in the population, first maturation occurring between 101 and 115mm of total length, spawning period occurs from November to February for Abudefduf saxatilis and October to January for Stegastes variabilis. Reproductive period for A. saxatilis was positively related to air temperature and thermic amplitude, but the environmental clue most likely to influence this rhythm is photoperiod. Transects with visual census of males guarding eggs were also a reliable tool for finding reproductive period in these demersal, egg-guarder species.Esse estudo apresenta dados sobre a reprodução de Abudefduf saxatilis, uma espécie habitante de costões rochosos no litoral norte do estado de São Paulo. Os peixes foram coletados com anzol e isca num total de 73 indivíduos, foram medidos, pesados, dissecados, seu sexo e maturidade gonadal foram analisados, primeiro macroscopicamente, depois parte desse material foi levado para confirmação microscópica. Censos visuais também foram feitos para observar a presença de ovos. Os resultados apontam para uma equivalência entre o número de machos e fêmeas na população, a primeira maturação ocorre entre 101 e 115 mm de comprimento total, a desova ocorre entre os meses de novembro a fevereiro em Abudefduf saxatilis e outubro a janeiro em Stegastes variabilis. O período reprodutivo de A. saxatilis está positivamente relacionado à temperatura do ar e amplitude térmica, mas o indicador ambiental mais provável de

  6. Estimation of genome length

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The genome length is a fundamental feature of a species. This note outlined the general concept and estimation method of the physical and genetic length. Some formulae for estimating the genetic length were derived in detail. As examples, the genome genetic length of Pinus pinaster Ait. and the genetic length of chromosome Ⅵ of Oryza sativa L. were estimated from partial linkage data.

  7. Persistence Length of Stable Microtubules

    Science.gov (United States)

    Hawkins, Taviare; Mirigian, Matthew; Yasar, M. Selcuk; Ross, Jennifer

    2011-03-01

    Microtubules are a vital component of the cytoskeleton. As the most rigid of the cytoskeleton filaments, they give shape and support to the cell. They are also essential for intracellular traffic by providing the roadways onto which organelles are transported, and they are required to reorganize during cellular division. To perform its function in the cell, the microtubule must be rigid yet dynamic. We are interested in how the mechanical properties of stable microtubules change over time. Some ``stable'' microtubules of the cell are recycled after days, such as in the axons of neurons or the cilia and flagella. We measured the persistence length of freely fluctuating taxol-stabilized microtubules over the span of a week and analyzed them via Fourier decomposition. As measured on a daily basis, the persistence length is independent of the contour length. Although measured over the span of the week, the accuracy of the measurement and the persistence length varies. We also studied how fluorescently-labeling the microtubule affects the persistence length and observed that a higher labeling ratio corresponded to greater flexibility. National Science Foundation Grant No: 0928540 to JLR.

  8. Length-dependent modulation of cytoskeletal remodeling and mechanical energetics in airway smooth muscle

    National Research Council Canada - National Science Library

    Kim, Hak Rim; Liu, Katrina; Roberts, Thomas J; Hai, Chi-Ming

    2011-01-01

    ... and branched actin filaments in shortened ASM. The mechanical energy output/input ratio during sinusoidal length oscillation was dependent on muscle length, oscillatory amplitude, and cholinergic activation...

  9. Telomere length and depression

    DEFF Research Database (Denmark)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Rode, Line

    2016-01-01

    BACKGROUND: Depression has been cross-sectionally associated with short telomeres as a measure of biological age. However, the direction and nature of the association is currently unclear. AIMS: We examined whether short telomere length is associated with depression cross-sectionally as well...... as prospectively and genetically. METHOD: Telomere length and three polymorphisms, TERT, TERC and OBFC1, were measured in 67 306 individuals aged 20-100 years from the Danish general population and associated with register-based attendance at hospital for depression and purchase of antidepressant medication....... RESULTS: Attendance at hospital for depression was associated with short telomere length cross-sectionally, but not prospectively. Further, purchase of antidepressant medication was not associated with short telomere length cross-sectionally or prospectively. Mean follow-up was 7.6 years (range 0...

  10. Myofilament length dependent activation

    Energy Technology Data Exchange (ETDEWEB)

    de Tombe, Pieter P.; Mateja, Ryan D.; Tachampa, Kittipong; Mou, Younss Ait; Farman, Gerrie P.; Irving, Thomas C. (IIT); (Loyola)

    2010-05-25

    The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a beat-to-beat basis. The main cellular mechanism that underlies this phenomenon is an increase in the responsiveness of cardiac myofilaments to activating Ca{sup 2+} ions at a longer sarcomere length, commonly referred to as myofilament length-dependent activation. This review focuses on what molecular mechanisms may underlie myofilament length dependency. Specifically, the roles of inter-filament spacing, thick and thin filament based regulation, as well as sarcomeric regulatory proteins are discussed. Although the 'Frank-Starling law of the heart' constitutes a fundamental cardiac property that has been appreciated for well over a century, it is still not known in muscle how the contractile apparatus transduces the information concerning sarcomere length to modulate ventricular pressure development.

  11. A Characteristic Particle Length

    CERN Document Server

    Roberts, Mark D

    2015-01-01

    It is argued that there are characteristic intervals associated with any particle that can be derived without reference to the speed of light $c$. Such intervals are inferred from zeros of wavefunctions which are solutions to the Schr\\"odinger equation. The characteristic length is $\\ell=\\beta^2\\hbar^2/(8Gm^3)$, where $\\beta=3.8\\dots$; this length might lead to observational effects on objects the size of a virus.

  12. Equilibrium CO bond lengths

    Science.gov (United States)

    Demaison, Jean; Császár, Attila G.

    2012-09-01

    Based on a sample of 38 molecules, 47 accurate equilibrium CO bond lengths have been collected and analyzed. These ultimate experimental (reEX), semiexperimental (reSE), and Born-Oppenheimer (reBO) equilibrium structures are compared to reBO estimates from two lower-level techniques of electronic structure theory, MP2(FC)/cc-pVQZ and B3LYP/6-311+G(3df,2pd). A linear relationship is found between the best equilibrium bond lengths and their MP2 or B3LYP estimates. These (and similar) linear relationships permit to estimate the CO bond length with an accuracy of 0.002 Å within the full range of 1.10-1.43 Å, corresponding to single, double, and triple CO bonds, for a large number of molecules. The variation of the CO bond length is qualitatively explained using the Atoms in Molecules method. In particular, a nice correlation is found between the CO bond length and the bond critical point density and it appears that the CO bond is at the same time covalent and ionic. Conditions which permit the computation of an accurate ab initio Born-Oppenheimer equilibrium structure are discussed. In particular, the core-core and core-valence correlation is investigated and it is shown to roughly increase with the bond length.

  13. Observations on oesophageal length.

    Science.gov (United States)

    Kalloor, G J; Deshpande, A H; Collis, J L

    1976-01-01

    The subject of oesophageal length is discussed. The great variations in the length of the oesophagus in individual patients is noted, and the practical use of its recognition in oesophageal surgery is stressed. An apprasial of the various methods available for this measurement is made; this includes the use of external chest measurement, endoscopic measurement, and the measurement of the level of the electrical mucosal potential change. Correlative studies of these various methods are made, and these show a very high degree of significance. These studies involved simultaneous measurement of external and internal oesophageal length in 26 patients without a hiatal hernia or gastro-oesophageal length in 26 patients without a hiatal hernia or gastro-oesophageal reflux symptoms, 42 patients with sliding type hiatal hernia, and 17 patients with a peptic stricture in association with hiatal hernia. The method of measuring oesophageal length by the use of the external chest measurement, that is, the distance between the lower incisor teeth and the xiphisternum, measured with the neck fully extended and the patient lying supine, is described in detail, its practical application in oesophageal surgery is illustrated, and its validity tested by internal measurements. The findings of this study demonstrate that the external chest measurement provides a mean of assessing the true static length of the oesophagus, corrected for the size of the individual. Images PMID:941114

  14. Mappability and Read Length

    Directory of Open Access Journals (Sweden)

    Wentian eLi

    2014-11-01

    Full Text Available Power-law distributions are the main functional form forthe distribution of repeat size and repeat copy number in the human genome. When the genome is broken into fragments for sequencing, the limited size offragments and reads may prevent an unique alignment of repeatsequences to the reference sequence. Repeats in the human genome canbe as long as $10^4$ bases, or $10^5-10^6$ bases when allowing for mismatches between repeat units. Sequence reads from these regions are therefore unmappable when the read length is in the range of $10^3$ bases.With the read length of exactly 1000 bases, slightly more than 1% of theassembled genome, and slightly less than 1% of the 1kbreads, are unmappable, excluding the unassembled portion of the humangenome (8% in GRCh37. The slow decay (long tail ofthe power-law function implies a diminishing return in convertingunmappable regions/reads to become mappable with the increase of theread length, with the understanding that increasing read length willalways move towards the direction of 100% mappability.

  15. Telomere Length and Mortality

    DEFF Research Database (Denmark)

    Kimura, Masayuki; Hjelmborg, Jacob V B; Gardner, Jeffrey P

    2008-01-01

    telomeres predicted the death of the first co-twin better than the mTRFL did (mTRFL: 0.56, 95% confidence interval (CI): 0.49, 0.63; mTRFL(50): 0.59, 95% CI: 0.52, 0.66; mTRFL(25): 0.59, 95% CI: 0.52, 0.66; MTRFL: 0.60, 95% CI: 0.53, 0.67). The telomere-mortality association was stronger in years 3-4 than......Leukocyte telomere length, representing the mean length of all telomeres in leukocytes, is ostensibly a bioindicator of human aging. The authors hypothesized that shorter telomeres might forecast imminent mortality in elderly people better than leukocyte telomere length. They performed mortality...... analysis in 548 same-sex Danish twins (274 pairs) aged 73-94 years, of whom 204 pairs experienced the death of one or both co-twins during 9-10 years of follow-up (1997-2007). From the terminal restriction fragment length (TRFL) distribution, the authors obtained the mean TRFL (mTRFL) and the mean values...

  16. L/B参数对双桨大长宽比超肥大船型阻力性能的影响%The Effect of L/B Parameters on the Hampered Performance of an Ultra-Large Vessel with Twin Screws and Large Length-width Ratio

    Institute of Scientific and Technical Information of China (English)

    黄广茂

    2011-01-01

    In order to discuss the effect of parameters on the resisted performance of an ultra-large ship with twin propellers and large length-width ratio, and to establish the quantitative forecasting system of effective power of this land of vessel, the author makes the L/B serial ship model tests after series of B/T and Cb tests. Four model vessels are involved in the L/B tests, with each tested with three hydrostatic resistance of different displacement. The tests generate the coefficient map of remaining resistance within the range ofL/B=8.0~11.65 and the map showing the effect of L/B parameters on the remaining resistance coefficient for correction, which offers some conclusions which will surely benefit the vessel designers.%为了探讨船型参数L/B对双桨大长宽比超肥大船型阻力性能的影响,建立该船型有效功率的定量预报系统,作者在B/T系列和CB系列船模试验之后,又进行了L/B系列船模试验.L/B系列船模共4艘,通过每条船模3个不同排水量的静水阻力试验,给出了L/B=8.0~11.65范围的剩余阻力系数图谱和L/B参数影响对剩余阻力系数的修正图谱,获得了一些有益的结论,供设计部门使用参考.

  17. The ideal dimensions of a Halbach cylinder of finite length

    DEFF Research Database (Denmark)

    Bjørk, Rasmus

    2011-01-01

    but with a possible shorter length is considered. The external radius and the length of the Halbach cylinder with the smallest possible dimensions are found as a function of a desired internal radius, length of the sample volume and mean flux density. It is shown that the optimal ratio between the outer and inner...... radius of the Halbach cylinder does not depend on the length of the sample volume. Finally, the efficiency of a finite length Halbach cylinder is considered and compared with the case of a cylinder of infinite length. The most efficient dimensions for a Halbach cylinder are found and it is shown...

  18. Relativistic length agony continued

    Directory of Open Access Journals (Sweden)

    Redžić D.V.

    2014-01-01

    Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

  19. Ground Wood Fiber Length Distributions

    OpenAIRE

    Lauri Ilmari Salminen; Sari Liukkonen; Alava, Mikko J.

    2014-01-01

    This study considers ground wood fiber length distributions arising from pilot grindings. The empirical fiber length distributions appear to be independent of wood fiber length as well as feeding velocity. In terms of mathematics the fiber fragment distributions of ground wood pulp combine an exponential distribution for high-length fragments and a power-law distribution for smaller lengths. This implies that the fiber length distribution is influenced by the stone surface. A fragmentation-ba...

  20. discouraged by queue length

    Directory of Open Access Journals (Sweden)

    P. R. Parthasarathy

    2001-01-01

    Full Text Available The transient solution is obtained analytically using continued fractions for a state-dependent birth-death queue in which potential customers are discouraged by the queue length. This queueing system is then compared with the well-known infinite server queueing system which has the same steady state solution as the model under consideration, whereas their transient solutions are different. A natural measure of speed of convergence of the mean number in the system to its stationarity is also computed.

  1. The ideal dimensions of a Halbach cylinder of finite length

    CERN Document Server

    Bjørk, R

    2014-01-01

    In this paper the smallest or optimal dimensions of a Halbach cylinder of a finite length for a given sample volume and desired flux density are determined using numerical modeling and parameter variation. A sample volume that is centered in and shaped as the Halbach cylinder bore but with a possible shorter length is considered. The external radius and the length of the Halbach cylinder with the smallest possible dimensions are found as a function of a desired internal radius, length of the sample volume and mean flux density. It is shown that the optimal ratio between the outer and inner radius of the Halbach cylinder does not depend on the length of the sample volume. Finally, the efficiency of a finite length Halbach cylinder is considered and compared with the case of a cylinder of infinite length. The most efficient dimensions for a Halbach cylinder are found and it is shown that the efficiency increases slowly with the length of the cylinder.

  2. Ground Wood Fiber Length Distributions

    Directory of Open Access Journals (Sweden)

    Lauri Ilmari Salminen

    2014-01-01

    Full Text Available This study considers ground wood fiber length distributions arising from pilot grindings. The empirical fiber length distributions appear to be independent of wood fiber length as well as feeding velocity. In terms of mathematics the fiber fragment distributions of ground wood pulp combine an exponential distribution for high-length fragments and a power-law distribution for smaller lengths. This implies that the fiber length distribution is influenced by the stone surface. A fragmentation-based model is presented that allows reproduction of the empirical results.

  3. Penile length-somatometric parameters relationship in healthy Egyptian men.

    Science.gov (United States)

    Shalaby, M E; Almohsen, A E-R M; El Shahid, A R; Abd Al-Sameaa, M T; Mostafa, T

    2015-05-01

    This study aimed to assess the penile length-somatometric parameters relationship in healthy Egyptian men. Two thousand physically normal men (22-40 years) were subjected to measurement of stretched penile length, glans penis, testis size, index finger, weight, height, span, body mass index (BMI), waist circumference, hip circumference and waist/hip ratio. The mean stretched penile length of the studied subjects was 13.84 ± 1.35 cm (range 12-19 cm), and the mean glans penis length was 2.6 ± 0.4 cm (range 1.7-3.8 cm). Penile length demonstrated positive significant correlation with glans penis length, index finger length, BMI and significant negative correlation with waist/hip ratio. On the other hand, penile length demonstrated nonsignificant correlation with age, weight, height, waist circumference, span or testicular size. It is concluded that the penile length-somatometric parameters relationship in healthy Egyptian men is mostly related to glans penis and index finger lengths.

  4. FETAL FOOT LENGTH AND HAND LENGTH: RELATIONSHIP WITH CROWN RUMP LENGTH AND GESTATIONAL AGE

    Directory of Open Access Journals (Sweden)

    Garima

    2015-12-01

    Full Text Available BACKGROUND Estimation of gestational age of fetus is of great medicolegal importance. Multiple parameters of the fetal anatomical measurements are in use. However, gestational age assessment may be difficult in fetus with anencephaly, hydrocephalus, short limb dysplasia, post mortem destruction or in mutilated case. Study of literature suggests that fetal foot has a characteristic pattern of normal growth and the fetal foot shows gradual increase in length relative to the length of the embryo and could be used to estimate gestational age. The purpose of the present study is to determine the accuracy in estimating gestational age using fetal foot and hand length by studying its relation with crown rump length in the foetuses of Manipuri origin. AIMS AND OBJECTIVES 1 To study the relationship between fetal crown rump length and fetal hand and foot length, thereby determining the accuracy in estimating gestational age by a cross-sectional study. MATERIALS AND METHODS A total of 100 formalin fixed fetuses of Manipuri origin, obtained from the Department of Obstetrics and Gynaecology, Regional Institute of Medical Sciences, Imphal, were included in the study, carried out in the Department of Anatomy, from February 2015 to July 2015. The parameters studied were crown rump length, foot length and hand length of fetuses. The data was analysed using SPSS software by regression analysis. Graphs were also plotted to determine pattern of growth and their correlation with crown rump length if any. RESULTS A total of 100 fetuses were studied, of which 43 were females and 57 were males. The mean foot length and hand length progressively increased with increase in crown rump length. Measurements were not significantly different in right or left side or among male and female fetuses. A statistically significant linear relationship was seen between foot length and crown rump length of the fetus (r=0.980, p<0.0001 and hand length and crown rump length of the fetus

  5. Leukocyte telomere length variation due to DNA extraction method.

    Science.gov (United States)

    Denham, Joshua; Marques, Francine Z; Charchar, Fadi J

    2014-12-04

    Telomere length is indicative of biological age. Shorter telomeres have been associated with several disease and health states. There are inconsistencies throughout the literature amongst relative telomere length measured by quantitative PCR (qPCR) and different extraction methods or kits used. We quantified whole-blood leukocyte telomere length using the telomere to single copy gene (T/S) ratio by qPCR in 20 young (18-25 yrs) men after extracting DNA using three common extraction methods: Lahiri and Nurnberger (high salt) method, PureLink Genomic DNA Mini kit (Life Technologies) and QiaAmp DNA Mini kit (Qiagen). Telomere length differences of DNA extracted from the three extraction methods was assessed by one-way analysis of variance (ANOVA). DNA purity differed between extraction methods used (P=0.01). Telomere length was impacted by the DNA extraction method used (P=0.01). Telomeres extracted using the Lahiri and Nurnberger method (mean T/S ratio: 2.43, range: 1.57-3.02) and PureLink Genomic DNA Mini Kit (mean T/S ratio: 2.57, range: 2.24-2.80) did not differ (P=0.13). Likewise, QiaAmp and Purelink-extracted telomeres were not statistically different (P=0.14). The Lahiri-extracted telomeres, however, were significantly shorter than those extracted using the QiaAmp DNA Mini Kit (mean T/S ratio: 2.71, range: 2.32-3.02; P=0.003). DNA purity was associated with telomere length. There are discrepancies between the length of leukocyte telomeres extracted from the same individuals according to the DNA extraction method used. DNA purity could be responsible for the discrepancy in telomere length but this will require validation studies. We recommend using the same DNA extraction kit when quantifying leukocyte telomere length by qPCR or when comparing different cohorts to avoid erroneous associations between telomere length and traits of interest.

  6. IMPEDANCE OF FINITE LENGTH RESISTOR

    Energy Technology Data Exchange (ETDEWEB)

    KRINSKY, S.; PODOBEDOV, B.; GLUCKSTERN, R.L.

    2005-05-15

    We determine the impedance of a cylindrical metal tube (resistor) of radius a, length g, and conductivity {sigma}, attached at each end to perfect conductors of semi-infinite length. Our main interest is in the asymptotic behavior of the impedance at high frequency, k >> 1/a. In the equilibrium regime, , the impedance per unit length is accurately described by the well-known result for an infinite length tube with conductivity {sigma}. In the transient regime, ka{sup 2} >> g, we derive analytic expressions for the impedance and wakefield.

  7. Polyketide chain length control by chain length factor.

    Science.gov (United States)

    Tang, Yi; Tsai, Shiou-Chuan; Khosla, Chaitan

    2003-10-22

    Bacterial aromatic polyketides are pharmacologically important natural products. A critical parameter that dictates product structure is the carbon chain length of the polyketide backbone. Systematic manipulation of polyketide chain length represents a major unmet challenge in natural product biosynthesis. Polyketide chain elongation is catalyzed by a heterodimeric ketosynthase. In contrast to homodimeric ketosynthases found in fatty acid synthases, the active site cysteine is absent from the one subunit of this heterodimer. The precise role of this catalytically silent subunit has been debated over the past decade. We demonstrate here that this subunit is the primary determinant of polyketide chain length, thereby validating its designation as chain length factor. Using structure-based mutagenesis, we identified key residues in the chain length factor that could be manipulated to convert an octaketide synthase into a decaketide synthase and vice versa. These results should lead to novel strategies for the engineered biosynthesis of hitherto unidentified polyketide scaffolds.

  8. Curve Length Estimation using Vertix Chain Code Curve Length Estimation

    Directory of Open Access Journals (Sweden)

    Habibollah Haron

    2010-09-01

    Full Text Available Most of the applications in image analysis are based on Freeman chain code. In this paper, for the first time, vertex chain code (VCC proposed by Bribiesca is applied to improve length estimation of the 2D digitized curve. The chain code has some preferences such as stable in shifting, turning, mirroring movement of image and has normalized starting point. Due to the variety of length estimator methods, we focused on the three specific techniques. First, the way Bribiesca proposed which is based on counting links between vertices; second, based on maximum length digital straight segments (DSSs and lastly local metrics. The results of these length estimators with the real perimeter are compared. Results thus obtained exhibits thatlength estimation using VCC is nearest to the actual length.

  9. Flux saturation length of sediment transport.

    Science.gov (United States)

    Pähtz, Thomas; Kok, Jasper F; Parteli, Eric J R; Herrmann, Hans J

    2013-11-22

    Sediment transport along the surface drives geophysical phenomena as diverse as wind erosion and dune formation. The main length scale controlling the dynamics of sediment erosion and deposition is the saturation length Ls, which characterizes the flux response to a change in transport conditions. Here we derive, for the first time, an expression predicting Ls as a function of the average sediment velocity under different physical environments. Our expression accounts for both the characteristics of sediment entrainment and the saturation of particle and fluid velocities, and has only two physical parameters which can be estimated directly from independent experiments. We show that our expression is consistent with measurements of Ls in both aeolian and subaqueous transport regimes over at least 5 orders of magnitude in the ratio of fluid and particle density, including on Mars.

  10. Impedance of Finite Length Resistor

    CERN Document Server

    Krinsky, Samuel; Podobedov, Boris

    2005-01-01

    We determine the impedance of a cylindrical metal tube (resistor) of radius a and length g, attached at each end to perfect conductors of semi-infinite length. Our main interest is in the behavior of the impedance at high frequency (k>>1/a). In the equilibrium regime, ka2

  11. Line Lengths and Starch Scores.

    Science.gov (United States)

    Moriarty, Sandra E.

    1986-01-01

    Investigates readability of different line lengths in advertising body copy, hypothesizing a normal curve with lower scores for shorter and longer lines, and scores above the mean for lines in the middle of the distribution. Finds support for lower scores for short lines and some evidence of two optimum line lengths rather than one. (SKC)

  12. Gestation length in farmed reindeer.

    Science.gov (United States)

    Shipka, M P; Rowell, J E

    2010-01-01

    Reindeer (Rangifer tarandus tarundus) are the only cervids indigenous to the arctic environment. In Alaska, reindeer are a recognized agricultural species and an economic mainstay for many native populations. Traditionally raised in extensive free-ranging systems, a recent trend toward intensive farming requires a more in-depth knowledge of reproductive management. Reported gestation length in reindeer varies, ranging from 198 to 229 d in studies performed at the University of Alaska Fairbanks. A switchback study that manipulated only breeding date demonstrated a mean increase in gestation length of 8.5 d among females bred early in the season. The negative correlation between conception date and gestation length is consistent with reindeer research at other locations and reports of variable gestation length in a growing number of domestic and non-domestic species. This paper reviews the phenomenon in reindeer and discusses some of the factors known to affect gestation length as well as possible areas for future research.

  13. Reserved-Length Prefix Coding

    CERN Document Server

    Baer, Michael B

    2008-01-01

    Huffman coding finds an optimal prefix code for a given probability mass function. Consider situations in which one wishes to find an optimal code with the restriction that all codewords have lengths that lie in a user-specified set of lengths (or, equivalently, no codewords have lengths that lie in a complementary set). This paper introduces a polynomial-time dynamic programming algorithm that finds optimal codes for this reserved-length prefix coding problem. This has applications to quickly encoding and decoding lossless codes. In addition, one modification of the approach solves any quasiarithmetic prefix coding problem, while another finds optimal codes restricted to the set of codes with g codeword lengths for user-specified g (e.g., g=2).

  14. Financial Key Ratios

    Directory of Open Access Journals (Sweden)

    Tănase Alin-Eliodor

    2014-08-01

    Full Text Available 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.

  15. Offer/Acceptance Ratio.

    Science.gov (United States)

    Collins, Mimi

    1997-01-01

    Explores how human resource professionals, with above average offer/acceptance ratios, streamline their recruitment efforts. Profiles company strategies with internships, internal promotion, cooperative education programs, and how to get candidates to accept offers. Also discusses how to use the offer/acceptance ratio as a measure of program…

  16. Compression Ratio Adjuster

    Science.gov (United States)

    Akkerman, J. W.

    1982-01-01

    New mechanism alters compression ratio of internal-combustion engine according to load so that engine operates at top fuel efficiency. Ordinary gasoline, diesel and gas engines with their fixed compression ratios are inefficient at partial load and at low-speed full load. Mechanism ensures engines operate as efficiently under these conditions as they do at highload and high speed.

  17. Specialized ratio analysis.

    Science.gov (United States)

    Wyer, J C; Salzinger, F H

    1983-01-01

    Many common management techniques have little use in managing a medical group practice. Ratio analysis, however, can easily be adapted to the group practice setting. Acting as broad-gauge indicators, financial ratios provide an early warning of potential problems and can be very useful in planning for future operations. The author has gathered a collection of financial ratios which were developed by participants at an education seminar presented for the Virginia Medical Group Management Association. Classified according to the human element, system component, and financial factor, the ratios provide a good sampling of measurements relevant to medical group practices and can serve as an example for custom-tailoring a ratio analysis system for your medical group.

  18. Pairing versus quarteting coherence length

    CERN Document Server

    Delion, Doru S

    2015-01-01

    We systematically analyse the coherence length in even-even nuclei. The pairing coherence length in the spin-singlet channel for the effective density dependent delta (DDD) and Gaussian interaction is estimated. We consider in our calculations bound states as well as narrow resonances. It turns out that the pairing gaps given by the DDD interaction are similar to those of the Gaussian potential if one renormalizes the radial width to the nuclear radius. The correlations induced by the pairing interaction have in all considered cases a long range character inside the nucleus and decrease towards the surface. The mean coherence length is larger than the geometrical radius for light nuclei and approaches this value for heavy nuclei. The effect of the temperature and states in continuum is investigated. Strong shell effects are evidenced, especially for protons. We generalize this concept to quartets by considering similar relations, but between proton and neutron pairs. The quartet coherence length has a similar...

  19. Length Invisibilization of Tachyonic Neutrinos

    Science.gov (United States)

    Estakhr, Ahmad Reza

    2016-09-01

    Faster than the speed of light particle such as tachyonic neutrino due to its superluminal nature disapper and is undetectable. L = iΩ-1Lo where, i =√{ - 1 } is imaginary Number, Ω = 1 /√{βs2 - 1 } is Estakhr's Omega factor, L is the Superluminal Length, Lo is the proper length, βs =Vs / c > 1 is superluminal speed parameter, Vs is Superluminal velocity and c is speed of light.

  20. Focal Length Affects Depicted Shape and Perception of Facial Images.

    Science.gov (United States)

    Třebický, Vít; Fialová, Jitka; Kleisner, Karel; Havlíček, Jan

    2016-01-01

    Static photographs are currently the most often employed stimuli in research on social perception. The method of photograph acquisition might affect the depicted subject's facial appearance and thus also the impression of such stimuli. An important factor influencing the resulting photograph is focal length, as different focal lengths produce various levels of image distortion. Here we tested whether different focal lengths (50, 85, 105 mm) affect depicted shape and perception of female and male faces. We collected three portrait photographs of 45 (22 females, 23 males) participants under standardized conditions and camera setting varying only in the focal length. Subsequently, the three photographs from each individual were shown on screen in a randomized order using a 3-alternative forced-choice paradigm. The images were judged for attractiveness, dominance, and femininity/masculinity by 369 raters (193 females, 176 males). Facial width-to-height ratio (fWHR) was measured from each photograph and overall facial shape was analysed employing geometric morphometric methods (GMM). Our results showed that photographs taken with 50 mm focal length were rated as significantly less feminine/masculine, attractive, and dominant compared to the images taken with longer focal lengths. Further, shorter focal lengths produced faces with smaller fWHR. Subsequent GMM revealed focal length significantly affected overall facial shape of the photographed subjects. Thus methodology of photograph acquisition, focal length in this case, can significantly affect results of studies using photographic stimuli perhaps due to different levels of perspective distortion that influence shapes and proportions of morphological traits.

  1. Impact of Cyclic Prefix length on OFDM system Capacity

    DEFF Research Database (Denmark)

    Rom, Christian; Sørensen, Troels Bundgaard; Mogensen, Preben Elgaard

    2005-01-01

    This paper is a study on the impact of the Cyclic Prefix (CP) length on the downlink Capacity in a base-band synchronized SISO-OFDM context. To measure this impact, the capacity, measured in bits per second per hertz, is chosen as quality parameter. The study shows how the lengthening of the CP......) the useful OFDM symbol duration, 2) the Signal to Noise Ratio (SNR) at the receiver and 3) the channel Power Delay Profile (PDP). Depending on the values of these parameters different optimum CP lengths are obtained. For a system using only one value of CP length we suggest an optimum value to be 4us...... for an OFDM symbol length of 40us and 6us for an OFDM symbol length of 80us....

  2. Spatial correlation length of normalized cone data in sand

    DEFF Research Database (Denmark)

    Firouzianbandpey, Sarah; Griffiths, D. V.; Ibsen, Lars Bo;

    2014-01-01

    it is rarely estimated during routine site investigations. Results from two different sites in the north of Denmark are reported in this paper, indicating quite strong anisotropy due to the depositional process, with significantly shorter spatial correlation lengths in the vertical direction. It is observed......The main topic of this study is to assess the anisotropic spatial correlation lengths of a sand layer deposit based on cone penetration testing with pore pressure measurement (CPTu) data. Spatial correlation length can be an important factor in reliability analysis of geotechnical systems, yet...... that the normalized cone resistance is a better estimator of spatial trends than the normalized friction ratio....

  3. Difference and ratio plots

    DEFF Research Database (Denmark)

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

    1995-01-01

    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...... 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....

  4. Comparison of Implant-Supported Crown Length Measured on Digitized Casts and Intraoral Radiographs

    NARCIS (Netherlands)

    Meijer, Henny J. A.; Telleman, Gerdien; Gareb, Chawan; Den Hartog, Laurens; Vissink, Arjan; Raghoebar, Gerry M.

    2012-01-01

    Correct measurement of crown length is important for calculating the crown-implant ratio. The aim of this study was to compare the length of implant-supported crowns measured on digitized casts and intraoral radiographs. Crown lengths were studied in 50 patients with 86 implant-supported crowns in t

  5. IMF Length Scales and Predictability: The Two Length Scale Medium

    Science.gov (United States)

    Collier, Michael R.; Szabo, Adam; Slavin, James A.; Lepping, R. P.; Kokubun, S.

    1999-01-01

    We present preliminary results from a systematic study using simultaneous data from three spacecraft, Wind, IMP 8 (Interplanetary Monitoring Platform) and Geotail to examine interplanetary length scales and their implications on predictability for magnetic field parcels in the typical solar wind. Time periods were selected when the plane formed by the three spacecraft included the GSE (Ground Support Equipment) x-direction so that if the parcel fronts were strictly planar, the two adjacent spacecraft pairs would determine the same phase front angles. After correcting for the motion of the Earth relative to the interplanetary medium and deviations in the solar wind flow from radial, we used differences in the measured front angle between the two spacecraft pairs to determine structure radius of curvature. Results indicate that the typical radius of curvature for these IMF parcels is of the order of 100 R (Sub E). This implies that there are two important IMF (Interplanetary Magnetic Field) scale lengths relevant to predictability: (1) the well-established scale length over which correlations observed by two spacecraft decay along a given IMF parcel, of the order of a few tens of Earth radii and (2) the scale length over which two spacecraft are unlikely to even observe the same parcel because of its curvature, of the order of a hundred Earth radii.

  6. CEBAF Upgrade Bunch Length Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion Univ., Norfolk, VA (United States)

    2016-05-01

    Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes without modifying the old procedures. Two of them can be used when the beam is not compressed longitudinally while the other one, the synchrotron light monitor, can be used with compressed or uncompressed beam.

  7. Keeping disease at arm's length

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    2015-01-01

    active ageing change everyday life with chronic disease, and how do older people combine an active life with a range of chronic diseases? The participants in the study use activities to keep their diseases at arm’s length, and this distancing of disease at the same time enables them to engage in social...... and physical activities at the activity centre. In this way, keeping disease at arm’s length is analysed as an ambiguous health strategy. The article shows the importance of looking into how active ageing is practised, as active ageing seems to work well in the everyday life of the older people by not giving...... emphasis to disease. The article is based on ethnographic fieldwork and uses vignettes of four participants to show how they each keep diseases at arm’s length....

  8. Spreading lengths of Hermite polynomials

    CERN Document Server

    Sánchez-Moreno, P; Manzano, D; Yáñez, R; 10.1016/j.cam.2009.09.043

    2009-01-01

    The Renyi, Shannon and Fisher spreading lengths of the classical or hypergeometric orthogonal polynomials, which are quantifiers of their distribution all over the orthogonality interval, are defined and investigated. These information-theoretic measures of the associated Rakhmanov probability density, which are direct measures of the polynomial spreading in the sense of having the same units as the variable, share interesting properties: invariance under translations and reflections, linear scaling and vanishing in the limit that the variable tends towards a given definite value. The expressions of the Renyi and Fisher lengths for the Hermite polynomials are computed in terms of the polynomial degree. The combinatorial multivariable Bell polynomials, which are shown to characterize the finite power of an arbitrary polynomial, play a relevant role for the computation of these information-theoretic lengths. Indeed these polynomials allow us to design an error-free computing approach for the entropic moments (w...

  9. Continuous lengths of oxide superconductors

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    2000-01-01

    A layered oxide superconductor prepared by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon. A continuous length of a second substrate ribbon is overlaid on the first substrate ribbon. Sufficient pressure is applied to form a bound layered superconductor precursor powder between the first substrate ribbon and the second substrate ribbon. The layered superconductor precursor is then heat treated to establish the oxide superconducting phase. The layered oxide superconductor has a smooth interface between the substrate and the oxide superconductor.

  10. Overview of bunch length measurements.

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A. H.

    1999-02-19

    An overview of particle and photon beam bunch length measurements is presented in the context of free-electron laser (FEL) challenges. Particle-beam peak current is a critical factor in obtaining adequate FEL gain for both oscillators and self-amplified spontaneous emission (SASE) devices. Since measurement of charge is a standard measurement, the bunch length becomes the key issue for ultrashort bunches. Both time-domain and frequency-domain techniques are presented in the context of using electromagnetic radiation over eight orders of magnitude in wavelength. In addition, the measurement of microbunching in a micropulse is addressed.

  11. Ratios of Normal Variables

    Directory of Open Access Journals (Sweden)

    George Marsaglia

    2006-05-01

    Full Text Available This article extends and amplifies on results from a paper of over forty years ago. It provides software for evaluating the density and distribution functions of the ratio z/w for any two jointly normal variates z,w, and provides details on methods for transforming a general ratio z/w into a standard form, (a+x/(b+y , with x and y independent standard normal and a, b non-negative constants. It discusses handling general ratios when, in theory, none of the moments exist yet practical considerations suggest there should be approximations whose adequacy can be verified by means of the included software. These approximations show that many of the ratios of normal variates encountered in practice can themselves be taken as normally distributed. A practical rule is developed: If a < 2.256 and 4 < b then the ratio (a+x/(b+y is itself approximately normally distributed with mean μ = a/(1.01b − .2713 and variance 2 = (a2 + 1/(b2 + .108b − 3.795 − μ2.

  12. Ratios of Normal Variables

    Directory of Open Access Journals (Sweden)

    George Marsaglia

    2006-05-01

    Full Text Available This article extends and amplifies on results from a paper of over forty years ago. It provides software for evaluating the density and distribution functions of the ratio z/w for any two jointly normal variates z,w, and provides details on methods for transforming a general ratio z/w into a standard form, (a+x/(b+y , with x and y independent standard normal and a, b non-negative constants. It discusses handling general ratios when, in theory, none of the moments exist yet practical considerations suggest there should be approximations whose adequacy can be verified by means of the included software. These approximations show that many of the ratios of normal variates encountered in practice can themselves be taken as normally distributed. A practical rule is developed: If a < 2.256 and 4 < b then the ratio (a+x/(b+y is itself approximately normally distributed with mean μ = a/(1.01b - .2713 and variance σ2 = (a2 + 1/(b2 + .108b - 3.795 μ2.

  13. Potential support ratios

    DEFF Research Database (Denmark)

    Kjærgaard, Søren; Canudas-Romo, Vladimir

    2017-01-01

    , 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......, historical data, and forecasted data. Cohort life expectancy takes future mortality improvements into account, unlike period life expectancy, leading to a higher prospective potential support ratio. Our results indicate that using cohort instead of period life expectancy returns around 0.5 extra younger...

  14. Length Normalization in XML Retrieval

    NARCIS (Netherlands)

    Kamps, Jaap; Rijke, Maarten de; Sigurbjörnsson, Börkur

    2005-01-01

    The full paper appeared as: J. Kamps, M. de Rijke, and B. Sigurbj¨ornsson, “Length Normalization in XML Retrieval,” In: Proceedings 27th Annual International ACM SIGIR Conference (SIGIR 2004), pages 80-87, 2004.

  15. Finite length Taylor Couette flow

    Science.gov (United States)

    Streett, C. L.; Hussaini, M. Y.

    1987-01-01

    Axisymmetric numerical solutions of the unsteady Navier-Stokes equations for flow between concentric rotating cylinders of finite length are obtained by a spectral collocation method. These representative results pertain to two-cell/one-cell exchange process, and are compared with recent experiments.

  16. 7 Length-weight relationship

    African Journals Online (AJOL)

    Administrator

    from which stomachs were extracted for the analysis of the food contents, using frequency of occurrence, numerical and ... both fish species showed strong correlation between the weight and length with correlation coefficient (r) and ..... Basic data on the assessment of Sphyraena ... review of methods and their application.

  17. Persistence length of dendronized polymers

    NARCIS (Netherlands)

    Mikhailov, I.V.; Darinskii, A.A.; Zhulina, E.B.; Borisov, O.V.; Leermakers, F.A.M.

    2015-01-01

    We present numerical results for the thermodynamic rigidity and induced persistence length of dendronized polymers with systematically varied topology of their grafts obtained by the Scheutjens-Fleer self-consistent field method. The results were compared to predictions of an analytical mean-fiel

  18. Fractional baud-length coding

    Directory of Open Access Journals (Sweden)

    J. Vierinen

    2011-06-01

    Full Text Available We present a novel approach for modulating radar transmissions in order to improve target range and Doppler estimation accuracy. This is achieved by using non-uniform baud lengths. With this method it is possible to increase sub-baud range-resolution of phase coded radar measurements while maintaining a narrow transmission bandwidth. We first derive target backscatter amplitude estimation error covariance matrix for arbitrary targets when estimating backscatter in amplitude domain. We define target optimality and discuss different search strategies that can be used to find well performing transmission envelopes. We give several simulated examples of the method showing that fractional baud-length coding results in smaller estimation errors than conventional uniform baud length transmission codes when estimating the target backscatter amplitude at sub-baud range resolution. We also demonstrate the method in practice by analyzing the range resolved power of a low-altitude meteor trail echo that was measured using a fractional baud-length experiment with the EISCAT UHF system.

  19. Cavity length below chute aerators

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    It is proved that air entrainment is one of the efficient measures dealing with cavi-tation control for the release works of hydropower projects. There are many factors to be considered in designing a chute aerator. One of the most important factors concerns the cavity length below the aerator,which has outstanding effects on air entrainment against cavitation damage. It is crucial to determine reasonable emergence angle for the calculation of the cavity length. In the present paper the overall effects of structural and hydraulic parameters on the emergence angle of the flow from the aerator were analyzed. Four improved expressions of the emer-gence angle with weight coefficient were investigated through experimental data of 68 points observed from 12 aerators of 6 hydropower projects,of both model and prototype,on the basis of error theory. A method to calculate the cavity length be-low aerators was suggested,which considers overall effects of the above men-tioned parameters. Comparison between the method in this paper and the other five methods of calculating the cavity length showed that the present method is much more reliable than the existing methods while the mean error of the method is less than others.

  20. Cavity length below chute aerators

    Institute of Scientific and Technical Information of China (English)

    WU JianHua; RUAN ShiPing

    2008-01-01

    It is proved that air entrainment is one of the efficient measures dealing with cavitation control for the release works of hydropower projects. There are many factors to be considered in designing a chute aerator. One of the most important factors concerns the cavity length below the aerator, which has outstanding effects on air entrainment against cavitation damage. It is crucial to determine reasonable emergence angle for the calculation of the cavity length. In the present paper the overall effects of structural and hydraulic parameters on the emergence angle of the flow from the aerator were analyzed. Four improved expressions of the emergence angle with weight coefficient were investigated through experimental data of 68 points observed from 12 aerators of 6 hydropower projects, of both model and prototype, on the basis of error theory. A method to calculate the cavity length below aerators was suggested, which considers overall effects of the above mentioned parameters. Comparison between the method in this paper and the other five methods of calculating the cavity length showed that the present method is much more reliable than the existing methods while the mean error of the method is less than others.

  1. Cyclic Codes of Length 2

    Indian Academy of Sciences (India)

    Manju Pruthi

    2001-11-01

    In this paper explicit expressions of + 1 idempotents in the ring $R = F_q[X]/\\langle X^{2^m}-1\\rangle$ are given. Cyclic codes of length 2 over the finite field , of odd characteristic, are defined in terms of their generator polynomials. The exact minimum distance and the dimension of the codes are obtained.

  2. The golden ratio in special relativity

    Energy Technology Data Exchange (ETDEWEB)

    Di Sigalotti, Leonardo G. [Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, IVIC, Apartado 21827, Caracas 1020A (Venezuela)]. E-mail: lsigalot@cassini.ivic.ve; Mejias, Antonio [Instituto Universitario Tecnologico de Ejido, IUTE, Avenida 25 de Noviembre, Ejido 5251, Estado Merida (Venezuela)]. E-mail: antoniojmm@cantv.net

    2006-11-15

    In this note we show that Euclid's construction of the golden rectangle can be used to derive both the dilation of time intervals and the Lorentz contraction of lengths as predicted by Einstein's theory of special relativity. In this simple exercise, the Lorentz factor arises as a direct consequence of the Pythagorean theorem, while the golden ratio, {phi}=1+5/2, is found to govern the transition from Newton's physics to relativistic mechanics.

  3. Gender Ratio in Dyslexia.

    Science.gov (United States)

    Miles, T. R.; Haslum, M. N.; Wheeler, T. J.

    1998-01-01

    A study involving 11,804 British children (age 10) found that when specified criteria for dyslexia were used, 269 children qualified as dyslexic. These included 223 boys and 46 girls, for a ratio of 4.51 to 1. Difficulties in interpreting these data are discussed and a defense of the criteria is provided. (Author/CR)

  4. The rectilinear Steiner ratio

    Directory of Open Access Journals (Sweden)

    PO de Wet

    2005-06-01

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

  5. Variation of H 2 bond length with magnetic field

    Science.gov (United States)

    Misra, Anirban; Panda, Anirban

    2008-11-01

    We find a new effect, namely, the variation of the ratio of concentrations of ortho- and para-isomers of hydrogen in thermal equilibrium in a uniform external magnetic field with field strength and temperature, that can be observed experimentally. The observation can determine the variation of bond length with the magnetic field strength.

  6. Comment on "Length-dependent translation of messenger RNA by ribosomes"

    CERN Document Server

    Zhang, Yunxin

    2011-01-01

    In recent paper [Phys. Rev. E {\\bf 83}, 042903 (2011)], a simple model for the translation of messenger RNA by ribosomes is provided, and the expression of translational ratio of protein is given. In this comments, varied methods to get this ratio are addressed. Depending on a different method, we find that, roughly speaking, this translational ratio decays exponentially with mRNA length in prokaryotic cell, and reciprocally with mRNA length in eukaryotic cells.

  7. Short Telomere Length and Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Scheller Madrid, Alexander; Rode, Line; Nordestgaard, Børge Grønne

    2016-01-01

    BACKGROUND: Short telomeres are associated with aging and have been associated with a high risk of ischemic heart disease in observational studies; however, the latter association could be due to residual confounding and/or reverse causation. We wanted to test the hypothesis that short telomeres...... are associated with high risk of ischemic heart disease using a Mendelian randomization approach free of reverse causation and of most confounding. METHODS: We genotyped 3 genetic variants in OBFC1 (oligonucleotide/oligosaccharide binding fold containing 1), TERT (telomerase reverse transcriptase), and TERC...... logistic and instrumental variable analysis for genetic estimates. RESULTS: Observationally, a 200-bp-shorter telomere length was associated with a multivariable adjusted hazard ratio for ischemic heart disease of 1.02 (95% CI, 1.01-1.03). Per allele, telomeres were shorter by 67 bp (73-60). In meta...

  8. Influence of recording length on reporting status

    DEFF Research Database (Denmark)

    Biltoft-Jensen, Anja Pia; Matthiessen, Jeppe; Fagt, Sisse;

    2009-01-01

    : To investigate the impact of recording length on reporting status, expressed as the ratio between energy intake and calculated basal metabolic rate (EI/BMR), the percentage of consumers of selected food items and the number reported food items per meal and eating occasions per day. Methods: Data from two...... different population samples were used for comparison. In total 138 adult volunteers (68 men and 70 women aged 20-59 years) recruited within the Copenhagen area and 2504 (1153 men and 1351 women aged 20-59 y) randomly selected adults from the Danish Civil Registration System, whom participated...... in a validation study and the Danish National Survey of Dietary Habits and Physical Activity 2000-2002, respectively. Both studies had a cross-sectional design. Volunteers and participants completed a pre-coded food diary every day for 7 consecutive days. BMR was predicted from equations. Results...

  9. Entrance Length and Turbulence Transition in Microflows

    Science.gov (United States)

    Wereley, Steve; Lee, Sangyoup; Gui, Lichuan

    2002-11-01

    Since microfabrication techniques are typically planar processes, microchannel flows typically have significant predevelopment due to the upstream reservoir having the same height as the microchannel. The main concerns of the current study are categorized into finding the effects of typical microchannel geometry on the velocity entrance length in the laminar flow regime and providing the turbulence transitional Reynolds number range using the details of the velocity profile rather than global measurements of pressure drop. A rectangular micro-channel of aspect ratio 2.65 and the hydraulic diameter 380 um was used in this study. Micro particle image velocimetry measurement was performed to measure the velocity profiles. The entrance length is found to be reduced by about 45number occurs between 2100 and 2900-comparable to macroscale observations. Finally a new technique is proposed to measure the turbulence intensity of a flow directly from the PIV correlation function peak width. This new technique provides results comparable to traditional means of calculating turbulence intensity but is particularly useful in measuring microflows where the seeding density can be very low.

  10. The probabilistic distribution of metal whisker lengths

    Energy Technology Data Exchange (ETDEWEB)

    Niraula, D., E-mail: Dipesh.Niraula@rockets.utoledo.edu; Karpov, V. G., E-mail: victor.karpov@utoledo.edu [Department of Physics and Astronomy, University of Toledo, Toledo, Ohio 43606 (United States)

    2015-11-28

    Significant reliability concerns in multiple industries are related to metal whiskers, which are random high aspect ratio filaments growing on metal surfaces and causing shorts in electronic packages. We derive a closed form expression for the probabilistic distribution of metal whisker lengths. Our consideration is based on the electrostatic theory of metal whiskers, according to which whisker growth is interrupted when its tip enters a random local “dead region” of a weak electric field. Here, we use the approximation neglecting the possibility of thermally activated escapes from the “dead regions,” which is later justified. We predict a one-parameter distribution with a peak at a length that depends on the metal surface charge density and surface tension. In the intermediate range, it fits well the log-normal distribution used in the experimental studies, although it decays more rapidly in the range of very long whiskers. In addition, our theory quantitatively explains how the typical whisker concentration is much lower than that of surface grains. Finally, it predicts the stop-and-go phenomenon for some of the whiskers growth.

  11. Length of a Hanging Cable

    Directory of Open Access Journals (Sweden)

    Eric Costello

    2011-01-01

    Full Text Available The shape of a cable hanging under its own weight and uniform horizontal tension between two power poles is a catenary. The catenary is a curve which has an equation defined by a hyperbolic cosine function and a scaling factor. The scaling factor for power cables hanging under their own weight is equal to the horizontal tension on the cable divided by the weight of the cable. Both of these values are unknown for this problem. Newton's method was used to approximate the scaling factor and the arc length function to determine the length of the cable. A script was written using the Python programming language in order to quickly perform several iterations of Newton's method to get a good approximation for the scaling factor.

  12. INTERPOLATION WITH RESTRICTED ARC LENGTH

    Institute of Scientific and Technical Information of China (English)

    Petar Petrov

    2003-01-01

    For given data (ti,yi), I= 0,1,…,n,0 = t0 <t1 <…<tn = 1we study constrained interpolation problem of Favard type inf{‖f"‖∞|f∈W2∞[0,1],f(ti)=yi,i=0,…,n,l(f;[0,1])≤l0}, wherel(f";[0,1])=∫1 0 / 1+f'2(x)dx is the arc length off in [0,1]. We prove the existence of a solution f* of the above problem, that is a quadratic spline with a second derivative f"* , which coincides with one of the constants - ‖f"*‖∞,0,‖f"*‖∞ between every two consecutive knots. Thus, we extend a result ofKarlin concerning Favard problem, to the case of restricted length interpolation.

  13. Minimal Length, Measurability and Gravity

    Directory of Open Access Journals (Sweden)

    Alexander Shalyt-Margolin

    2016-03-01

    Full Text Available The present work is a continuation of the previous papers written by the author on the subject. In terms of the measurability (or measurable quantities notion introduced in a minimal length theory, first the consideration is given to a quantum theory in the momentum representation. The same terms are used to consider the Markov gravity model that here illustrates the general approach to studies of gravity in terms of measurable quantities.

  14. Why is digit ratio correlated to sports performance?

    Science.gov (United States)

    Kim, Tae Beom; Kim, Khae Hawn

    2016-01-01

    Second to fourth digit ratio is the ratio of second to fourth digit length. It has been known that digit ratio is sexually dimorphic in humans, such that males tend to have lower digit ratio (longer fourth digits relative to second digits) than females. Digit ratio is thought to be a biomarker of the balance between fetal testosterone (FT) and fetal estrogen (FE) in a relatively narrow developmental window at the end of the first trimester of pregnancy. On the contrary, the relationships between digit ratio and levels of sex steroids in adults are not clear. Most correlational studies between digit ratio and adult sex steroids have revealed that this association is statistically not significant. However, for many years, a lot of researches showed negative relationships between digit ratio and sports performance such as rugby, surfing, rowing, sprinting, endurance, and hand grip strength. Here, we discuss possible mechanisms about the relationships between digit ratio and sports performance. PMID:28119871

  15. Leg length, proportion, health and beauty: a review.

    Science.gov (United States)

    Bogin, Barry; Varela-Silva, Maria Inês

    2009-12-01

    Decomposing stature into its major components is proving to be a useful strategy to assess the antecedents of disease, morbidity and death in adulthood. Human leg length (foot + tibia + femur), sitting height (trunk length + head length) and their proportions (for example the relative leg length in proportion to stature, and the sitting height ratio [sitting height/stature x 100], among others) are used as epidemiological markers of risk for overweight (fatness), coronary heart disease, diabetes and certain cancers. There is also wide support for the use of relative leg length as an indicator of the quality of the environment for growth during infancy, childhood and the juvenile years of development. Human beings follow a cephalo-caudal gradient of growth, the pattern of growth common to all mammals. A special feature of the human pattern is that between birth and puberty the legs grow relatively faster than other post-cranial body segments. For groups of children and youth, short stature due to relatively short legs (i.e. a high sitting height ratio) is generally a marker of an adverse environment. The development of human body proportions is the product of environmental x genomic interactions, although few if any specific genes are known. The short stature homeobox-containing gene (SHOX) is the first genomic region that may be relevant to human body proportions. For example, one of the SHOX related disorders is Turner syndrome. However, in most cases research has been showing that environment is a more powerful force to shape leg length and body proportions than genes. Leg length and proportion are important in the perception of human beauty, which is often considered a sign of health and fertility. There are a variety of cosmetic, fashion, and surgical interventions to enhance perceived or actual leg length.

  16. Telomere length and the risk of lung cancer.

    Science.gov (United States)

    Jang, Jin Sung; Choi, Yi Young; Lee, Won Kee; Choi, Jin Eun; Cha, Sung Ick; Kim, Yeon Jae; Kim, Chang Ho; Kam, Sin; Jung, Tae Hoon; Park, Jae Yong

    2008-07-01

    Telomeres play a key role in the maintenance of chromosome integrity and stability. There is growing evidence that short telomeres induce chromosome instability and thereby promote the development of cancer. We investigated the association of telomere length and the risk of lung cancer. Relative telomere length in peripheral blood lymphocytes was measured by quantitative polymerase chain reaction in 243 lung cancer patients and 243 healthy controls that were frequency-matched for age, sex and smoking status. Telomere length was significantly shorter in lung cancer patients than in controls (mean +/- standard deviation: 1.59 +/- 0.75 versus 2.16 +/- 1.10, P telomere length, the risk of lung cancer was found to increase as telomere length shortened (P(trend) telomere length was used as the cutoff between long and short telomeres, individuals with short telomeres were at a significantly higher risk of lung cancer than those with long telomeres (adjusted odds ratio = 3.15, 95% confidence interval = 2.12-4.67, P telomere length on the risk of lung cancer was more pronounced in patients with small cell carcinoma than in those with squamous cell carcinoma and adenocarcinoma (P = 0.001, test for homogeneity). These findings suggest that shortening of the telomeres may be a risk factor for lung cancer, and therefore, the presence of shortened telomeres may be used as a marker for susceptibility to lung cancer.

  17. Constrained length minimum inductance gradient coil design.

    Science.gov (United States)

    Chronik, B A; Rutt, B K

    1998-02-01

    A gradient coil design algorithm capable of controlling the position of the homogeneous region of interest (ROI) with respect to the current-carrying wires is required for many advanced imaging and spectroscopy applications. A modified minimum inductance target field method that allows the placement of a set of constraints on the final current density is presented. This constrained current minimum inductance method is derived in the context of previous target field methods. Complete details are shown and all equations required for implementation of the algorithm are given. The method has been implemented on computer and applied to the design of both a 1:1 aspect ratio (length:diameter) central ROI and a 2:1 aspect ratio edge ROI gradient coil. The 1:1 design demonstrates that a general analytic method can be used to easily obtain very short gradient coil designs for use with specialized magnet systems. The edge gradient design demonstrates that designs that allow imaging of the neck region with a head sized gradient coil can be obtained, as well as other applications requiring edge-of-cylinder regions of uniformity.

  18. A note on trader Sharpe Ratios.

    Directory of Open Access Journals (Sweden)

    John M Coates

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

  19. A note on trader Sharpe Ratios.

    Science.gov (United States)

    Coates, John M; Page, Lionel

    2009-11-25

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

  20. Does the Mother or Father Determine the Offspring Sex Ratio? Investigating the Relationship between Maternal Digit Ratio and Offspring Sex Ratio.

    Directory of Open Access Journals (Sweden)

    Tae Beom Kim

    Full Text Available In mammals, high parental testosterone levels present around the time of conception are thought to skew offspring sex ratio toward sons. The second to fourth digit ratio (digit ratio is now widely accepted as a negative correlate of prenatal testosterone. Thus, we investigated the association between digit ratio and offspring sex ratio.A total of 508 Korean patients (257 males and 251 females less than 60 years old who had one or more offspring were prospectively enrolled. The lengths of the 2nd and 4th digits of the right hand were measured by a single investigator using a digital vernier calliper. Next, the patients' lifetime offspring birth sex ratios were investigated.Maternal (rather than paternal digit ratio was significantly associated with the number of sons (r = -0.153, p = 0.015, number of daughters (r = 0.130, p = 0.039, and offspring sex ratio (r = -0.171, p = 0.007. And, the maternal digit ratio was a significant factor for predicting offspring sex ratio (B = -1.620, p = 0.008 on multiple linear regression analysis. The female patients with a lower digit ratio (< 0.95 were found to have a higher offspring sex ratio (0.609 versus 0.521, p = 0.046 compared to those with a higher digit ratio (≥ 0.95. Furthermore, females in the low digit ratio group have a probability 1.138 greater of having sons than females in the high digit ratio group.Maternal digit ratio was negatively associated with offspring sex ratio. Females with a lower digit ratio were more likely to have more male offspring compared to those with a higher digit ratio. Thus, our results suggest that the sex of offspring might be more influenced by maternal rather than paternal factors.

  1. Pharmacologically induced erect penile length and stretched penile length are both good predictors of post-inflatable prosthesis penile length.

    Science.gov (United States)

    Osterberg, E C; Maganty, A; Ramasamy, R; Eid, J F

    2014-01-01

    Inflatable penile prosthesis (IPP) remains the gold standard for the surgical treatment of refractory erectile dysfunction; however, current literature to aid surgeons on how best to counsel patients on their postoperative inflated penile length is lacking. The aim of this study was to identify preoperative parameters that could better predict postoperative penile length following insertion of an IPP. Twenty men were enrolled in a prospective study examining penile lengths before and after IPP surgery. Patients with Peyronie's disease were excluded from this analysis. Baseline preoperative characteristics, including body mass index, history of hypertension, diabetes, Sexual Health Inventory for Men scores and/or prior radical prostatectomy were recorded. All patients underwent implantation with a three-piece inflatable Coloplast penile prosthesis. We compared stretched penile length to pharmacologically induced erect lengths. Postoperatively, we measured inflated penile lengths at 6 weeks and assessed patients' perception of penile size at 12 weeks. The median (±interquartile range) stretched penile length and pharmacologically induced erect penile length was 15 (±3) and 14.25 (±2) cm, respectively (P=0.5). Median post-prosthesis penile length (13.5±2.13 cm) was smaller than preoperative pharmacologically induced length (P=0.02) and preoperative stretched penile length (P=0.01). The majority of patients (70%) had a decrease in penile length (median loss 0.5±1.5 cm); however, this loss was perceptible by 43% of men. Stretched penile length and pharmacologically induced erect penile length were equally good predictors of postoperative inflated length (Spearman's correlation 0.8 and 0.9, respectively). Pharmacologically induced erect penile length and stretched penile lengths are equal predictors of post-prosthesis penile length. The majority of men will experience some decrease in penile length following prosthesis implantation; however <50% report a

  2. Testing of Cotton Fiber Length

    Institute of Scientific and Technical Information of China (English)

    刘若华; 李汝勤

    2001-01-01

    To understand the influences of actual sampling conditions on cotton fiber length testing, this article presents a theoretic study on the distributions and fibrogram of the sample taken out by sampler from ideal sliver at a certain angle. From the distributions expression it can be found that the size of the sampler and the sampling angle are important factors which affect sampling, but if the sampling width is narrow enough, the influence of the sampling angle on the distributions and fibrogram is small enough to be omitted. This is an important conclusion for sampling, in light of this, some suggestions for designing new type sampler are put forward.

  3. Tau hadronic branching ratios

    CERN Document Server

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

    1996-01-01

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

  4. Focal Length Affects Depicted Shape and Perception of Facial Images.

    Directory of Open Access Journals (Sweden)

    Vít Třebický

    Full Text Available Static photographs are currently the most often employed stimuli in research on social perception. The method of photograph acquisition might affect the depicted subject's facial appearance and thus also the impression of such stimuli. An important factor influencing the resulting photograph is focal length, as different focal lengths produce various levels of image distortion. Here we tested whether different focal lengths (50, 85, 105 mm affect depicted shape and perception of female and male faces. We collected three portrait photographs of 45 (22 females, 23 males participants under standardized conditions and camera setting varying only in the focal length. Subsequently, the three photographs from each individual were shown on screen in a randomized order using a 3-alternative forced-choice paradigm. The images were judged for attractiveness, dominance, and femininity/masculinity by 369 raters (193 females, 176 males. Facial width-to-height ratio (fWHR was measured from each photograph and overall facial shape was analysed employing geometric morphometric methods (GMM. Our results showed that photographs taken with 50 mm focal length were rated as significantly less feminine/masculine, attractive, and dominant compared to the images taken with longer focal lengths. Further, shorter focal lengths produced faces with smaller fWHR. Subsequent GMM revealed focal length significantly affected overall facial shape of the photographed subjects. Thus methodology of photograph acquisition, focal length in this case, can significantly affect results of studies using photographic stimuli perhaps due to different levels of perspective distortion that influence shapes and proportions of morphological traits.

  5. Generalizations of Brandl's theorem on Engel length

    Science.gov (United States)

    Quek, S. G.; Wong, K. B.; Wong, P. C.

    2013-04-01

    Let n Engel cycle generated by g and h. The length of the Engel cycle is m-n. A group G is said to have Engel length r, if all the length of the Engel cycles in G divides r. In this paper we discuss the Brandl's theorem on Engel length and give some of its generalizations.

  6. REDUCTION OF STILLING BASIN LENGTH WITH TALL END SILL

    Institute of Scientific and Technical Information of China (English)

    FATHI-MOGHADAM Manoochehr; HAGHIGHIPOUR Sadegh; LASHKAR-ARA Babak; AGHTOUMAN Peyman

    2011-01-01

    Experiments were conducted to characterize forced hydraulic jumps in stilling basins for enforced cases due to tail water level or dam site arrangement and construction.The case with a single tall sill was simulated in a horizontal flume downstream of a sluice gate.Results of experiments are compared with the classical hydraulic jump,and significant effect of tall sill on dissipation of energy in shorter distance was confirmed.Furthermore,the generated jumps were classified based on the ratio of sill height to basin length,and a simple design criterion was proposed to estimate the basin length for a desired jump and particular inflow.

  7. Statistical analysis of friction sleeve length effects on soil classification

    Science.gov (United States)

    Saussus, D. R.; Frost, J. D.; Dejong, J. T.

    2004-10-01

    The cone penetration test (CPT) provides profiles of the tip resistance, sleeve friction, and pore water pressure encountered while penetrating the subsurface. These parameters are used either directly or indirectly to classify the soil types present and to obtain geotechnical design parameters. However, fundamental discrepancies exist in the manner by which these parameters are measured. This paper describes the results of a study that shows the sleeve friction measurement introduces unnecessary redundancy due to the length of the standard friction sleeve compared to the measurement increment. Further, the high sleeve length to measurement increment ratio results in filtering and smoothing of the friction data, thereby causing the variability of the friction between the soil and the cone sleeve to be underestimated. The importance of understanding the role of the sleeve length on measurements is demonstrated using synthetically generated friction profiles and estimating the profiles that would be measured using sleeves of different lengths. Differences in how the soils are classified as a function of the sleeve length used to obtain each profile are illustrated. Solutions are presented to validate the synthetic sleeve friction profiles, to demonstrate the filtering and smoothing effects of the friction sleeve on the data, and to explain the implications of the sleeve length on soil classification. Copyright

  8. Muscle: Bone ratios in beef rib sections.

    Science.gov (United States)

    Dolezal, H G; Murphey, C E; Smith, G C; Carpenter, Z L; McCartor, M

    1982-01-01

    Thirty-eight steers and thirty heifers (14 to 17 months of age, from F(1) Hereford × Brahman cows bred to Angus or Hereford bulls), were either forage-fed for 123 days on millet-bermudagrass pasture or grain-fed for 90 days on a high-concentrate diet and were then commercially slaughtered. Warm carcass weights ranged from 167·8 kg to 324·3 kg. At 24 h post mortem, Texas Agricultural Experiment Station personnel (1) assigned scores or took measurements on each carcass for all factors used in yield grading and quality grading, (2) measured the length of hind leg (HL) and carcass length (CL) and (3) assigned a score for carcass muscling (MS) and, as appropriate, made an adjusted longissimus muscle area (ALA) evaluation. The 9th-10th-11th rib section from one side of each carcass was physically separated into longissimus muscle, fat, 'other soft tissue' and bone and ether extract determinations of the longissimus muscle and 'other soft tissue' components were made and used to adjust the yields of each of these components to a fat-free basis. Muscle to bone ratios ranged from 2·38 to 4·37. With both age and carcass weight held constant, diet, breed and sex explained only 35·8% of the variation in muscle to bone ratio. The best simple correlation with muscle to bone ratio was ALA/CL (r = ·59). Other measures significantly correlated with muscle to bone ratio included ALA (r = 0·55), MS (r = 0·50) and carcass weight (r = 0·49). Multiple regression analyses identified a three-variable subset comprised of ALA, carcass weight and CL which was related (P carcass measures useful for predicting muscle to bone ratio.

  9. Perception of Length to Width Relations of City Squares

    Directory of Open Access Journals (Sweden)

    Harold T. Nefs

    2013-04-01

    Full Text Available In this paper, we focus on how people perceive the aspect ratio of city squares. Earlier research has focused on distance perception but not so much on the perceived aspect ratio of the surrounding space. Furthermore, those studies have focused on “open” spaces rather than urban areas enclosed by walls, houses and filled with people, cars, etc. In two experiments, we therefore measured, using a direct and an indirect method, the perceived aspect ratio of five city squares in the historic city center of Delft, the Netherlands. We also evaluated whether the perceived aspect ratio of city squares was affected by the position of the observer on the square. In the first experiment, participants were asked to set the aspect ratio of a small rectangle such that it matched the perceived aspect ratio of the city square. In the second experiment, participants were asked to estimate the length and width of the city square separately. In the first experiment, we found that the perceived aspect ratio was in general lower than the physical aspect ratio. However, in the second experiment, we found that the calculated ratios were close to veridical except for the most elongated city square. We conclude therefore that the outcome depends on how the measurements are performed. Furthermore, although indirect measurements are nearly veridical, the perceived aspect ratio is an underestimation of the physical aspect ratio when measured in a direct way. Moreover, the perceived aspect ratio also depends on the location of the observer. These results may be beneficial to the design of large open urban environments, and in particular to rectangular city squares.

  10. Effect of contact ratio on spur gear dynamic load

    Science.gov (United States)

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

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

  11. Coordinate Variation in Lengths of Deoxyribonucleic Acid Molecules and Head Lengths in Morphological Variants of Bacteriophage T4

    Science.gov (United States)

    Mosig, Gisela; Carnighan, Janet Renshaw; Bibring, Jane Baxandall; Cole, Robert; Bock, Hans-Georg Otto; Bock, Susan

    1972-01-01

    We have investigated three classes of small bacteriophage T4 particles which differ from normal T4 particles in length of their deoxyribonucleic acid (DNA), in head length, in protein content, and in density. The different particles contain DNA molecules measuring 0.90, 0.77, or 0.67, respectively, of the normal T4 length. An additional class of viable particles contains DNA molecules of 1.1 unit length. These discrete differences in DNA length correspond to discrete differences in length (but not width) of the respective heads and are roughly proportional to the resulting differences in head volumes. The measured relative dimensions of the different heads fit best the relative dimensions predicted by a quasi-icosahedral model in which the smallest T4 head corresponds to an icosahedron with a triangulation number T = 21. The mid-portion of this structure is thought to be elongated by adding successive rows of gene 23 protein hexamers, the normal T4 head having three added rows. Different mutants produce small particles of the three classes in varying proportions, but no mutant produces exclusively particles of a single class. Particles of each class, with indistinguishable DNA content, show additional minor differences in protein content, as measured by differences in buoyant density and in the relative ratio of 32P to 35S. Images PMID:5025493

  12. High-Ratio Gear Train

    Science.gov (United States)

    Lefever, A. E.

    1982-01-01

    Proposed arrangement of two connected planetary differentials results in gear ratio many times that obtainable in conventional series gear assembly of comparable size. Ratios of several thousand would present no special problems. Selection of many different ratios is available with substantially similar gear diameters. Very high gear ratios would be obtained from small mechanism.

  13. A two-scale damage model with material length

    Science.gov (United States)

    Dascalu, Cristian

    2009-09-01

    The Note presents the formulation of a class of two-scale damage models involving a micro-structural length. A homogenization method based on asymptotic developments is employed to deduce the macroscopic damage equations. The damage model completely results from energy-based micro-crack propagation laws, without supplementary phenomenological assumptions. We show that the resulting two-scale model has the property of capturing micro-structural lengths. When damage evolves, the micro-structural length is given by the ratio of the surface density of energy dissipated during the micro-crack growth and the macroscopic damage energy release rate per unit volume of the material. The use of fracture criteria based on resistance curves or power laws for sub-critical growth of micro-cracks leads to quasi-brittle and, respectively, time-dependent damage models. To cite this article: C. Dascalu, C. R. Mecanique 337 (2009).

  14. The Effect of Height, Wing Length, and Wing Symmetry on Tabebuia rosea Seed Dispersal

    Directory of Open Access Journals (Sweden)

    Yasmeen Moussa

    2014-12-01

    Full Text Available The relationship between the vertical drop height and the horizontal distance traveled (dispersal ratio was investigated for a sample of fifty Tabebuia rosea seeds by dropping the seeds from five heights ranging from 1.00 to 2.00 meters. The dispersal ratio was found to be a constant 0.16 m/m for these heights. The effects of total seed length and asymmetry of seed wings on dispersal ratio were also measured using separate samples of fifty Tabebuia rosea seeds. It was found that neither seed length nor asymmetry had a significant effect on the dispersal ratio.

  15. Queue-length Variations In A Two-Restaurant Problem

    CERN Document Server

    Chakrabarti, Anindya S

    2008-01-01

    This paper attempts to find out numerically the distribution of the queue-length ratio in the context of a model of preferential attachment. Here we consider two restaurants only and a large number of customers (agents) who come to these restaurants. Each day the same number of agents sequentially arrives and decides which restaurant to enter. If all the agents literally follow the crowd then there is no difference between this model and the famous `P\\'olya's Urn' model. But as agents alter their strategies different kind of dynamics of the model is seen. It is seen from numerical results that the existence of a distribution of the fixed points is quite robust and it is also seen that in some cases the variations in the ratio of the queue-lengths follow a power-law.

  16. Fundamental ratios and logarithmic periodicity in human limb bones.

    Science.gov (United States)

    Pietak, Alexis; Ma, Siyan; Beck, Caroline W; Stringer, Mark D

    2013-05-01

    Fundamental mathematical relationships are widespread in biology yet there is little information on this topic with regard to human limb bone lengths and none related to human limb bone volumes. Forty-six sets of ipsilateral upper and lower limb long bones and third digit short bones were imaged by computed tomography. Maximum bone lengths were measured manually and individual bone volumes calculated from computed tomography images using a stereologic method. Length ratios of femur : tibia and humerus : ulna were remarkably similar (1.21 and 1.22, respectively) and varied little (bone volume ratios varied much more than upper limb ratios. The relationship between bone length and volume was found to be well described by power laws, with R(2) values ranging from 0.983 to 0.995. The most striking finding was a logarithmic periodicity in bone length moving from distal to proximal up the limb (upper limb λ = 0.72, lower limb λ = 0.93). These novel data suggest that human limb bone lengths and volumes follow fundamental and highly conserved mathematical relationships, which may contribute to our understanding of normal and disordered growth, stature estimation, and biomechanics.

  17. Gestation length and birth weight in relation to intake of marine n-3 fatty acids

    DEFF Research Database (Denmark)

    Olsen, S.F.; Hansen, H.S.; Secher, N.J.;

    1995-01-01

    between n- 3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n......-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate....

  18. Gestation length and birth weight in relation to intake of marine n-3 fatty acids

    DEFF Research Database (Denmark)

    Olsen, S.F.; Hansen, Harald S.; Secher, N.J.;

    1995-01-01

    between n-3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n......-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate....

  19. Information, polarization and term length in democracy

    DEFF Research Database (Denmark)

    Schultz, Christian

    2008-01-01

    This paper considers term lengths in a representative democracy where the political issue divides the population on the left-right scale. Parties are ideologically different and better informed about the consequences of policies than voters are. A short term length makes the government more accou...... the uncertainty is large and parties are not very polarized. Partisan voters always prefer a long term length. When politicians learn while in office a long term length becomes more attractive for swing voters....

  20. 28 CFR 551.4 - Hair length.

    Science.gov (United States)

    2010-07-01

    ... to an inmate hair care services which comply with applicable health and sanitation requirements. ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Hair length. 551.4 Section 551.4 Judicial... Hair length. (a) The Warden may not restrict hair length if the inmate keeps it neat and clean. (b)...

  1. String matching with variable length gaps

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Vildhøj, Hjalte Wedel

    2012-01-01

    We consider string matching with variable length gaps. Given a string T and a pattern P consisting of strings separated by variable length gaps (arbitrary strings of length in a specified range), the problem is to find all ending positions of substrings in T that match P. This problem is a basic...

  2. Root canal length measurement in teeth with electrolyte compensation.

    Science.gov (United States)

    Nam, K C; Kim, S C; Lee, S J; Kim, Y J; Kim, N G; Kim, D W

    2002-03-01

    Electronic root canal length measurement devices have made it easier and faster to measure the root canal length of a tooth compared with the conventional radiographic method. Of these electronic apex locators, the frequency-dependent type features greater accuracy and convenience in operation. However, its accuracy is still influenced by the presence of blood and/or the various electrolytes used in root canal therapy. This study describes the development of a new frequency-dependent electronic apex locator featuring electrolyte compensation, utilising an impedance ratio and voltage difference technique to minimise the influence of electrolytes on the accuracy of root canal length measurement. The errors for distances from file tips to apical constrictions were determined in vivo with the device operating with electrolyte compensation. The measured lengths were compared with the true lengths of the extracted teeth determined using a microscope. The mean error was +0.14+/-0.27mm, and 95.2% of the measurements were within the clinical tolerance of +/-0.5mm. It was also found that the degree of accuracy was not dependent on the size of the apical foramen (p = 0.74).

  3. Joint variable frame rate and length analysis for speech recognition under adverse conditions

    DEFF Research Database (Denmark)

    Tan, Zheng-Hua; Kraljevski, Ivan

    2014-01-01

    This paper presents a method that combines variable frame length and rate analysis for speech recognition in noisy environments, together with an investigation of the effect of different frame lengths on speech recognition performance. The method adopts frame selection using an a posteriori signal......-to-noise (SNR) ratio weighted energy distance and increases the length of the selected frames, according to the number of non-selected preceding frames. It assigns a higher frame rate and a normal frame length to a rapidly changing and high SNR region of a speech signal, and a lower frame rate and an increased...... frame length to a steady or low SNR region. The speech recognition results show that the proposed variable frame rate and length method outperforms fixed frame rate and length analysis, as well as standalone variable frame rate analysis in terms of noise-robustness....

  4. Relative length of human kidney as more precise measuring of normal kidney

    Directory of Open Access Journals (Sweden)

    Ilić Goran

    2010-01-01

    Full Text Available Introduction. Malformations in kidney development and kidney diseases are accompanied with changes in their size. For kidney evaluation in clinical practice, the kidney length is the most widely used measurement, since it provides the most precise results and it is easy to perform. Recently, the measurement of relative renal length has become more preferable as it takes into account the body height. The aim of this study was to measure both the absolute and relative length of normal cadaveric kidneys according to the body height, sex and age. Material and methods. In this study, we examined 95 adult cadaveric kidneys, without renal and vascular impairment, their age ranging from 23-87 years. To determine the period of the most abundant changes in kidney length, we separated them into a 10-year range. The relative renal length was calculated using the kidney length anybody height ratio (kidney/body ratio. Results. The absolute and relative length of left kidney in males was longer than the right one, with a statistically significant correlation. In females, the left kidney length was also longer than the right one, however, without a statistical significance. In contrast to the absolute length, the relative length of both kidneys did not show a significant difference between sexes, and did not manifest a significant decrease with age. There was a significant correlation between the kidney length and the subject’s height. Conclusion. The relative renal length represents kidney size better than the absolute renal length because it eliminates sex and height differences until the age of 59 year. From the seventh decade of life, there is a significant decrease in both the absolute and relative renal length.

  5. Inheritance of telomere length in a bird.

    Directory of Open Access Journals (Sweden)

    Thorsten Horn

    Full Text Available Telomere dynamics are intensively studied in human ageing research and epidemiology, with many correlations reported between telomere length and age-related diseases, cancer and death. While telomere length is influenced by environmental factors there is also good evidence for a strong heritable component. In human, the mode of telomere length inheritance appears to be paternal and telomere length differs between sexes, with females having longer telomeres than males. Genetic factors, e.g. sex chromosomal inactivation, and non-genetic factors, e.g. antioxidant properties of oestrogen, have been suggested as possible explanations for these sex-specific telomere inheritance and telomere length differences. To test the influence of sex chromosomes on telomere length, we investigated inheritance and sex-specificity of telomere length in a bird species, the kakapo (Strigops habroptilus, in which females are the heterogametic sex (ZW and males are the homogametic (ZZ sex. We found that, contrary to findings in humans, telomere length was maternally inherited and also longer in males. These results argue against an effect of sex hormones on telomere length and suggest that factors associated with heterogamy may play a role in telomere inheritance and sex-specific differences in telomere length.

  6. Length dependence of rectification in organic co-oligomer spin rectifiers

    Science.gov (United States)

    Gui-Chao, Hu; Zhao, Zhang; Ying, Li; Jun-Feng, Ren; Chuan-Kui, Wang

    2016-05-01

    The rectification ratio of organic magnetic co-oligomer diodes is investigated theoretically by changing the molecular length. The results reveal two distinct length dependences of the rectification ratio: for a short molecular diode, the charge-current rectification changes little with the increase of molecular length, while the spin-current rectification is weakened sharply by the length; for a long molecular diode, both the charge-current and spin-current rectification ratios increase quickly with the length. The two kinds of dependence switch at a specific length accompanied with an inversion of the rectifying direction. The molecular ortibals and spin-resolved transmission analysis indicate that the dominant mechanism of rectification suffers a change at this specific length, that is, from asymmetric shift of molecular eigenlevels to asymmetric spatial localization of wave functions upon the reversal of bias. This work demonstrates a feasible way to control the rectification in organic co-oligomer spin diodes by adjusting the molecular length. Project supported by the National Natural Science Foundation of China (Grant No. 11374195), the Natural Science Foundation of Shandong Province, China (Grant No. ZR2014AM017), the Taishan Scholar Project of Shandong Province, China, and the Excellent Young Scholars Research Fund of Shandong Normal University, China.

  7. Noise of Embedded High Aspect Ratio Nozzles

    Science.gov (United States)

    Bridges, James E.

    2011-01-01

    A family of high aspect ratio nozzles were designed to provide a parametric database of canonical embedded propulsion concepts. Nozzle throat geometries with aspect ratios of 2:1, 4:1, and 8:1 were chosen, all with convergent nozzle areas. The transition from the typical round duct to the rectangular nozzle was designed very carefully to produce a flow at the nozzle exit that was uniform and free from swirl. Once the basic rectangular nozzles were designed, external features common to embedded propulsion systems were added: extended lower lip (a.k.a. bevel, aft deck), differing sidewalls, and chevrons. For the latter detailed Reynolds-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) simulations were made to predict the thrust performance and to optimize parameters such as bevel length, and chevron penetration and azimuthal curvature. Seventeen of these nozzles were fabricated at a scale providing a 2.13 inch diameter equivalent area throat." ! The seventeen nozzles were tested for far-field noise and a few data were presented here on the effect of aspect ratio, bevel length, and chevron count and penetration. The sound field of the 2:1 aspect ratio rectangular jet was very nearly axisymmetric, but the 4:1 and 8:1 were not, the noise on their minor axes being louder than the major axes. Adding bevel length increased the noise of these nozzles, especially on their minor axes, both toward the long and short sides of the beveled nozzle. Chevrons were only added to the 2:1 rectangular jet. Adding 4 chevrons per wide side produced some decrease at aft angles, but increased the high frequency noise at right angles to the jet flow. This trend increased with increasing chevron penetration. Doubling the number of chevrons while maintaining their penetration decreased these effects. Empirical models of the parametric effect of these nozzles were constructed and quantify the trends stated above." Because it is the objective of the Supersonics Project that

  8. Axial Globe Length in Congenital Ptosis.

    Science.gov (United States)

    Takahashi, Yasuhiro; Kang, Hyera; Kakizaki, Hirohiko

    2015-01-01

    To compare axial globe length between affected and unaffected sides in patients with unilateral congenital ptosis. This prospective observational study included 37 patients (age range: 7 months to 58 years). The axial globe length, margin reflex distance-1 (MRD-1), and refractive power were measured. The axial globe length difference was calculated by subtracting the axial globe length on the unaffected side from that of the affected side. The relationships among axial globe length differences, MRD-1 on the affected sides, and patient ages were analyzed using multiple regression analysis. No significant differences were found in the axial globe length between sides (P = .677). The axial globe length difference was 0.17 ± 0.30 mm (mean ± standard deviation), and two patients (5.4%), aged 32 to 57 years, showed axial globe length more than 0.67 mm longer (corresponding to a refractive power of 2 diopters) on the affected side compared to the unaffected side. The multiple regression model between axial globe length difference, patient age, and MRD-1 on the affected sides was less appropriate (YAGL = 0.003XAGE-0.048XMRD-1 +0.112; r = 0.338; adjusted r2 = 0.062; P = .127). The cylindrical power was greater on the affected side (P = .046), although the spherical power was not different between sides (P = .657). No significant difference was identified in the axial globe length between sides, and only 5% of non-pediatric patients showed an axial globe length more than 0.67 mm longer on the affected side. Congenital ptosis may have little effect on axial globe length elongation, and the risk of axial myopia-induced anisometropic amblyopia may be low in patients with unilateral congenital ptosis. Copyright 2015, SLACK Incorporated.

  9. Diabetes mellitus and the eye: axial length

    OpenAIRE

    Huntjens, B.; O’Donnell, C.

    2006-01-01

    Background and aims: The refractive error of the eye is dependent on its axial length. Refractive error is known to fluctuate significantly in poorly controlled diabetic patients. Recently it has been reported that human eyes fluctuate in axial length during the day. However, this change is not detectable in all subjects, suggesting physiological influences such as diet. The purpose of this study was to investigate fluctuations in axial length and blood glucose levels (BGLs) in diabetic patie...

  10. Fibonacci Lengths of Certain Nilpotent 2-Groups

    Institute of Scientific and Technical Information of China (English)

    H. DOOSTIE; A. T. ADNANI

    2007-01-01

    In this paper, we study two classes of 2-generated 2-groups of nilpotency class 2 classified by Kluempen in 2002 and also a class of finite 2-groups of high nilpotency class for their Fibonacci lengths.Their involvement in certain interesting sequences of Tribonacci numbers gives us some explicit formulas for the Fibonacci lengths and this adds to the small class of finite groups for which the Fibonacci length are known.

  11. Large Slip Length over a Nanopatterned Surface

    Institute of Scientific and Technical Information of China (English)

    LI Ding; DI Qin-Feng; LI Jing-Yuan; QIAN Yue-Hong; FANG Hai-Ping

    2007-01-01

    A thermodynamic method is employed to analyse the slip length of hydrophobic nanopatterned surface.The maximal slip lengths with respect to the hydrophobicity of the nanopatterned surface are computed.It is found that the slip length reaches more than 50μm if the nanopatterned surfaces have a contact angle larger than 160°.Such results are expected to find extensive applications in micro-channels and helpful to understand recent experimental observations of the slippage of nanopatterned surfaces.

  12. Dither Cavity Length Controller with Iodine Locking

    Directory of Open Access Journals (Sweden)

    Lawson Marty

    2016-01-01

    Full Text Available A cavity length controller for a seeded Q-switched frequency doubled Nd:YAG laser is constructed. The cavity length controller uses a piezo-mirror dither voltage to find the optimum length for the seeded cavity. The piezo-mirror dither also dithers the optical frequency of the output pulse. [1]. This dither in optical frequency is then used to lock to an Iodine absorption line.

  13. New length operator for loop quantum gravity

    CERN Document Server

    Ma, Yongge; Yang, Jinsong

    2010-01-01

    An alternative expression for the length operator in loop quantum gravity is presented. The operator is background-independent, symmetric, positive semi-definite, and well-defined on the kinematical Hilbert space. The expression for the regularized length operator can moreover be understood both from a simple geometrical perspective as the average of a formula relating the length to area, volume and flux operators, and also consistently as the result of direct substitution of the densitized triad operator with the functional derivative operator into the regularized expression of the length. Both these derivations are discussed, and the origin of an undetermined overall factor in each case is also elucidated.

  14. On the attached length of orifices

    Science.gov (United States)

    Komkin, A. I.; Mironov, M. A.; Yudin, S. I.

    2012-11-01

    The attached length of orifices in reactive mufflers has been estimated based on numerical calculations by the finite-element method. The numerical results for a diaphragm in a duct are compared with the theoretical data obtained by Rayleigh, Fock, Karal, and Ingard. The dependence of the attached length on the diaphragm thickness is given. The results obtained are generalized for the case in which the orifice is a Helmholtz resonator neck. The effect of the resonator length on the attached length of the neck is analyzed.

  15. Mouse gestation length is genetically determined.

    Directory of Open Access Journals (Sweden)

    Stephen A Murray

    Full Text Available BACKGROUND: Preterm birth is an enormous public health problem, affecting over 12% of live births and costing over $26 billion in the United States alone. The causes are complex, but twin studies support the role of genetics in determining gestation length. Despite widespread use of the mouse in studies of the genetics of preterm birth, there have been few studies that actually address the precise natural gestation length of the mouse, and to what degree the timing of labor and birth is genetically determined. METHODOLOGY/PRINCIPAL FINDINGS: To further develop the mouse as a genetic model of preterm birth, we developed a high-throughput monitoring system and measured the gestation length in 15 inbred strains. Our results show an unexpectedly wide variation in overall gestation length between strains that approaches two full days, while intra-strain variation is quite low. Although litter size shows a strong inverse correlation with gestation length, genetic difference alone accounts for a significant portion of the variation. In addition, ovarian transplant experiments support a primary role of maternal genetics in the determination of gestation length. Preliminary analysis of gestation length in the C57BL/6J-Chr#(A/J/NaJ chromosome substitution strain (B.A CSS panel suggests complex genetic control of gestation length. CONCLUSIONS/SIGNIFICANCE: Together, these data support the role of genetics in regulating gestation length and present the mouse as an important tool for the discovery of genes governing preterm birth.

  16. Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy

    Science.gov (United States)

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

    2016-01-01

    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. PMID:28009000

  17. 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.

  18. A Service Ratio-Based Dynamic Fair Queueing Algorithm for Packet Switching Networks

    Institute of Scientific and Technical Information of China (English)

    YIN De-bin; XIE Jian-ying; ZHANG Yan; WU Jian-zhen; SUN Hua-li

    2008-01-01

    A new weighted fair queeetng algodthm is proposed,which uses the novel flow-based service ratio parameters to schedule flows.This solves the main drawback of traditional weighted fair quoneing algorithmsthe packet-based calculation of the weight parameters.In addition,this paper proposes a novel service ratio calculation method and a queue management techaology.The former adjusts the service ratio parameters adaptively based on the dynamics of the packet lengths and then solves the unfairness problem induced by the variable packet length.The latter impgoves the utilization of the server's queue buffeg and reduces the delay jitter throegh restricting the buffer length for each flow.

  19. An integrated restriction fragment length polymorphism--amplified fragment length polymorphism linkage map for cultivated sunflower.

    Science.gov (United States)

    Gedil, M A; Wye, C; Berry, S; Segers, B; Peleman, J; Jones, R; Leon, A; Slabaugh, M B; Knapp, S J

    2001-04-01

    Restriction fragment length polymorphism (RFLP) maps have been constructed for cultivated sunflower (Helianthus annuus L.) using three independent sets of RFLP probes. The aim of this research was to integrate RFLP markers from two sets with RFLP markers for resistance gene candidate (RGC) and amplified fragment length polymorphism (AFLP) markers. Genomic DNA samples of HA370 and HA372, the parents of the F2 population used to build the map, were screened for AFLPs using 42 primer combinations and RFLPs using 136 cDNA probes (RFLP analyses were performed on DNA digested with EcoRI, HindIII, EcoRV, or DraI). The AFLP primers produced 446 polymorphic and 1101 monomorphic bands between HA370 and HA372. The integrated map was built by genotyping 296 AFLP and 104 RFLP markers on 180 HA370 x HA372 F2 progeny (the AFLP marker assays were performed using 18 primer combinations). The HA370 x HA372 map comprised 17 linkage groups, presumably corresponding to the 17 haploid chromosomes of sunflower, had a mean density of 3.3 cM, and was 1326 cM long. Six RGC RFLP loci were polymorphic and mapped to three linkage groups (LG8, LG13, and LG15). AFLP markers were densely clustered on several linkage groups, and presumably reside in centromeric regions where recombination is reduced and the ratio of genetic to physical distance is low. Strategies for targeting markers to euchromatic DNA need to be tested in sunflower. The HA370 x HA372 map integrated 14 of 17 linkage groups from two independent RFLP maps. Three linkage groups were devoid of RFLP markers from one of the two maps.

  20. 23 CFR 658.13 - Length.

    Science.gov (United States)

    2010-04-01

    ... power unit behind the cab and on an over-cab rack. No State shall impose an overall length limitation of... may carry boats on the power unit so long as the length and width restrictions of the vehicles and...) in 23 CFR 658.19. (6) Munitions carriers using dromedary equipment. A truck tractor equipped with...

  1. Length-biased Weighted Maxwell Distribution

    Directory of Open Access Journals (Sweden)

    Kanak Modi

    2015-12-01

    Full Text Available The concept of length-biased distribution can be employed in development of proper models for life-time data. In this paper, we develop the length-biased form of Weighted Maxwell distribution (WMD. We study the statistical properties of the derived distribution including moments, moment generating function, hazard rate, reverse hazard rate, Shannon entropy and estimation of parameters

  2. Segment lengths influence hill walking strategies.

    Science.gov (United States)

    Sheehan, Riley C; Gottschall, Jinger S

    2014-08-22

    Segment lengths are known to influence walking kinematics and muscle activity patterns. During level walking at the same speed, taller individuals take longer, slower strides than shorter individuals. Based on this, we sought to determine if segment lengths also influenced hill walking strategies. We hypothesized that individuals with longer segments would display more joint flexion going uphill and more extension going downhill as well as greater lateral gastrocnemius and vastus lateralis activity in both directions. Twenty young adults of varying heights (below 155 cm to above 188 cm) walked at 1.25 m/s on a level treadmill as well as 6° and 12° up and downhill slopes while we collected kinematic and muscle activity data. Subsequently, we ran linear regressions for each of the variables with height, leg, thigh, and shank length. Despite our population having twice the anthropometric variability, the level and hill walking patterns matched closely with previous studies. While there were significant differences between level and hill walking, there were few hill walking variables that were correlated with segment length. In support of our hypothesis, taller individuals had greater knee and ankle flexion during uphill walking. However, the majority of the correlations were between tibialis anterior and lateral gastrocnemius activities and shank length. Contrary to our hypothesis, relative step length and muscle activity decreased with segment length, specifically shank length. In summary, it appears that individuals with shorter segments require greater propulsion and toe clearance during uphill walking as well as greater braking and stability during downhill walking.

  3. Influence of mandibular length on mouth opening

    NARCIS (Netherlands)

    Dijkstra, PU; Hof, AL; Stegenga, B; De Bont, LGM

    1999-01-01

    Theoretically, mouth opening not only reflects the mobility of the temporomandibular joints (TMJs) but also the mandibular length. Clinically, the exact relationship between mouth opening, mandibular length, and mobility of TMJs is unclear. To study this relationship 91 healthy subjects, 59 women an

  4. Extending electronic length frequency analysis in R

    DEFF Research Database (Denmark)

    Taylor, M. H.; Mildenberger, Tobias K.

    2017-01-01

    Electronic length frequency analysis (ELEFAN) is a system of stock assessment methods using length-frequency (LFQ) data. One step is the estimation of growth from the progression of LFQ modes through time using the von Bertalanffy growth function (VBGF). The option to fit a seasonally oscillating...

  5. Leaf Length Variation in Perennial Forage Grasses

    Directory of Open Access Journals (Sweden)

    Philippe Barre

    2015-08-01

    Full Text Available Leaf length is a key factor in the economic value of different grass species and cultivars in forage production. It is also important for the survival of individual plants within a sward. The objective of this paper is to discuss the basis of within-species variation in leaf length. Selection for leaf length has been highly efficient, with moderate to high narrow sense heritability. Nevertheless, the genetic regulation of leaf length is complex because it involves many genes with small individual effects. This could explain the low stability of QTL found in different studies. Leaf length has a strong response to environmental conditions. However, when significant genotype × environment interactions have been identified, their effects have been smaller than the main effects. Recent modelling-based research suggests that many of the reported environmental effects on leaf length and genotype × environment interactions could be biased. Indeed, it has been shown that leaf length is an emergent property strongly affected by the architectural state of the plant during significant periods prior to leaf emergence. This approach could lead to improved understanding of the factors affecting leaf length, as well as better estimates of the main genetic effects.

  6. Analysis of ureteral length in adult cadavers

    Directory of Open Access Journals (Sweden)

    Hugo F. F. Novaes

    2013-04-01

    Full Text Available Introduction In some occasions, correlations between human structures can help planning surgical intra-abdominal interventions. The previous determination of ureteral length helps pre-operatory planning of surgeries, reduces costs of auxiliary exams, the correct choice of double-J catheter with low morbidity and fewer symptoms, and an adequate adhesion to treatment. Objective To evaluate ureteral length in adult cadavers and to analyze its correlation with anthropometric measures. Materials and Methods: From April 2009 to January 2012 we determined ureteral length of adult cadavers submitted to necropsy and obtained the following measures: height, distance from shoulder to wrist, elbow-wrist, xiphoid appendix-umbilicus, umbilicus-pubis, xiphoid appendix-pubis and between iliac spines. We analyzed the correlations between ureteral length and those anthropometric measures. Results We dissected 115 ureters from 115 adult corpses from April 2009 to January 2012. Median ureteral length didn't vary between sexes or according to height. It was observed no correlation among ureteral length and all considered anthropometric measures in all analyzed subgroups and in general population. There were no significant differences between right and left ureteral measures. Conclusions There is no difference of ureteral length in relation to height or gender (male or female. There is no significant correlation among ureteral length and the considered anthropometric measures.

  7. 7 CFR 29.6024 - Length.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Length. 29.6024 Section 29.6024 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6024 Length. The linear measurement of cured tobacco leaves from...

  8. Deriving aerosol scattering ratio using range-resolved lidar ratio

    Indian Academy of Sciences (India)

    Reji K Dhaman; V Krishnakumar; V P Mahadevan Pillai; M Satyanarayana; K Raghunath

    2014-02-01

    The study on the optical characteristics of aerosol is carried out using the dual polarization lidar observations from the tropical inland station Gadanki (13.5°N, 79.2°E) for the period of observation during the year 2010. The summer and monsoon observation days show high scattering ratio at the tropical tropopause layer (TTL) and at the lower stratosphere region. The depolarization ratio is also high at this altitude due to the transport of particulates to the TTL layer by the active convection prevailing at the period. The study reveals more dependable values of scattering ratio that are seasonal and range-dependent.

  9. 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.

  10. Length contraction in Very Special Relativity

    CERN Document Server

    Dutta, Biplab

    2011-01-01

    Glashow and Cohen claim that many results of special theory of relativity (SR) like time dilation, relativistic velocity addition, etc, can be explained by using certain proper subgroups, of the Lorentz group, which collectively form the main body of Very special relativity (VSR). They did not mention about length contraction in VSR. Length contraction in VSR has not been studied at all. In this article we calculate how the length of a moving rod contracts in VSR, particularly in the HOM(2) version. The results are interesting in the sense that in general the length contraction formulas in VSR are different from SR but in many cases the two theories predict similar length contraction of moving rods.

  11. Screening length in dusty plasma crystals

    Science.gov (United States)

    Nikolaev, V. S.; Timofeev, A. V.

    2016-11-01

    Particles interaction and value of the screening length in dusty plasma systems are of great interest in dusty plasma area. Three inter-particle potentials (Debye potential, Gurevich potential and interaction potential in the weakly collisional regime) are used to solve equilibrium equations for two dusty particles suspended in a parabolic trap. The inter-particle distance dependence on screening length, trap parameter and particle charge is obtained. The functional form of inter-particle distance dependence on ion temperature is investigated and compared with experimental data at 200-300 K in order to test used potentials applicability to dusty plasma systems at room temperatures. The preference is given to the Yukawa-type potential including effective values of particle charge and screening length. The estimated effective value of the screening length is 5-15 times larger than the Debye length.

  12. Variable length representation in evolutionary electronics.

    Science.gov (United States)

    Zebulum, R S; Pacheco, M A; Vellasco, M

    2000-01-01

    This work investigates the application of variable length representation (VLR) evolutionary algorithms (EAs) in the field of Evolutionary Electronics. We propose a number of VLR methodologies that can cope with the main issues of variable length evolutionary systems. These issues include the search for efficient ways of sampling a genome space with varying dimensionalities, the task of balancing accuracy and parsimony of the solutions, and the manipulation of non-coding segments. We compare the performance of three proposed VLR approaches to sample the genome space: Increasing Length Genotypes, Oscillating Length Genotypes, and Uniformly Distributed Initial Population strategies. The advantages of reusing genetic material to replace non-coding segments are also emphasized in this work. It is shown, through examples in both analog and digital electronics, that the variable length genotype's representation is natural to this particular domain of application. A brief discussion on biological genome evolution is also provided.

  13. A Method for Determining Skeletal Lengths from DXA Images

    Directory of Open Access Journals (Sweden)

    Fogelman Ignac

    2007-11-01

    Full Text Available Abstract Background Skeletal ratios and bone lengths are widely used in anthropology and forensic pathology and hip axis length is a useful predictor of fracture. The aim of this study was to show that skeletal ratios, such as length of femur to height, could be accurately measured from a DXA (dual energy X-ray absorptiometry image. Methods 90 normal Caucasian females, 18–80 years old, with whole body DXA data were used as subjects. Two methods, linear pixel count (LPC and reticule and ruler (RET were used to measure skeletal sizes on DXA images and compared with real clinical measures from 20 subjects and 20 x-rays of the femur and tibia taken in 2003. Results Although both methods were highly correlated, the LPC inter- and intra-observer error was lower at 1.6% compared to that of RET at 2.3%. Both methods correlated positively with real clinical measures, with LPC having a marginally stronger correlation coefficient (r2 = 0.94; r2 = 0.84; average r2 = 0.89 than RET (r2 = 0.86; r2 = 0.84; average r2 = 0.85 with X-rays and real measures respectively. Also, the time taken to use LPC was half that of RET at 5 minutes per scan. Conclusion Skeletal ratios can be accurately and precisely measured from DXA total body scan images. The LPC method is easy to use and relatively rapid. This new phenotype will be useful for osteoporosis research for individuals or large-scale epidemiological or genetic studies.

  14. Kidney Length in Normal Korean Children

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In One; Cheon, Jung Eun [Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Young Seok [Dankook University College of Medicine, Cheonan (Korea, Republic of); Lee, Sun Wha [Ewha Womans University College of Medicine, Seoul (Korea, Republic of); Kim, Ok Hwa [Ajou University College of Medicine, Suwon (Korea, Republic of); Kim, Ji Hye [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Hong Dae [Kangnam Sacred Heart Hospital, Hanllym University College of Medicine, Seoul (Korea, Republic of); Sim, Jung Suk [Mothers Clinic, Bundang, Seongnam (Korea, Republic of)

    2010-09-15

    Renal length offers important information to detect or follow-up various renal diseases. The purpose of this study was to determine the kidney length of normal Korean children in relation to age, height, weight, body surface area (BSA), and body mass index (BMI). Children between 1 month and 15 years of age without urological abnormality were recruited. Children below 3rd percentile and over 97th percentile for height or weight were excluded. Both renal lengths were measured in the prone position three times and then averaged by experienced radiologists. The mean length and standard deviation for each age group was obtained, and regression equation was calculated between renal length and age, weight, height, BSA, and BMI, respectively. Renal length was measured in 550 children. Renal length grows rapidly until 24 month, while the growth rate is reduced thereafter. The regression equation for age is: renal length (mm) = 45.953 + 1.064 x age (month, {<=} 24 months) (R2 = 0.720) or 62.173 + 0.203 x age (months, > 24 months) (R2 = 0.711). The regression equation for height is: renal length (mm) = 24.494 + 0.457 x height (cm) (R2 = 0.894). The regression equation for weight is: renal length (mm) = 38.342 + 2.117 x weight (kg, {<=}18 kg) (R2 = 0.852) or 64.498 + 0.646 x weight (kg, > 18 kg) (R2 = 0.651). The regression equation for BSA is: renal length (mm) = 31.622 + 61.363 x BSA (m2, {<=} 0.7) (R2 = 0.857) or 52.717 + 29.959 x BSA (m2, > 0.7) (R2 = 0.715). The regression equation for BMI is: renal length (mm) = 44.474 + 1.163 x BMI (R2 = 0.079). This study provides data on the normal renal length and its association with age, weight, height, BSA and BMI. The results of this study will guide the detection and follow-up of renal diseases in Korean children

  15. Length-dependent modulation of cytoskeletal remodeling and mechanical energetics in airway smooth muscle.

    Science.gov (United States)

    Kim, Hak Rim; Liu, Katrina; Roberts, Thomas J; Hai, Chi-Ming

    2011-06-01

    Actin cytoskeletal remodeling is an important mechanism of airway smooth muscle (ASM) contraction. We tested the hypothesis that mechanical strain modulates the cholinergic receptor-mediated cytoskeletal recruitment of actin-binding and integrin-binding proteins in intact airway smooth muscle, thereby regulating the mechanical energetics of airway smooth muscle. We found that the carbachol-stimulated cytoskeletal recruitment of actin-related protein-3 (Arp3), metavinculin, and talin were up-regulated at short muscle lengths and down-regulated at long muscle lengths, suggesting that the actin cytoskeleton--integrin complex becomes enriched in cross-linked and branched actin filaments in shortened ASM. The mechanical energy output/input ratio during sinusoidal length oscillation was dependent on muscle length, oscillatory amplitude, and cholinergic activation. The enhancing effect of cholinergic stimulation on mechanical energy output/input ratio at short and long muscle lengths may be explained by the length-dependent modulation of cytoskeletal recruitment and crossbridge cycling, respectively. We postulate that ASM functions as a hybrid biomaterial, capable of switching between operating as a cytoskeleton-based mechanical energy store at short muscle lengths to operating as an actomyosin-powered mechanical energy generator at long muscle lengths. This postulate predicts that targeting the signaling molecules involved in cytoskeletal recruitment may provide a novel approach to dilating collapsed airways in obstructive airway disease.

  16. Elliptic nozzle aspect ratio effect on controlled jet propagation

    Science.gov (United States)

    Aravindh Kumar, S. M.; Rathakrishnan, Ethirajan

    2017-04-01

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

  17. Frailty and telomere length: cross-sectional analysis in 3537 older adults from the ESTHER cohort.

    Science.gov (United States)

    Saum, Kai-Uwe; Dieffenbach, Aida Karina; Müezzinler, Aysel; Müller, Heiko; Holleczek, Bernd; Stegmaier, Christa; Butterbach, Katja; Schick, Matthias; Canzian, Federico; Stammer, Hermann; Boukamp, Petra; Hauer, Klaus; Brenner, Hermann

    2014-10-01

    Both telomere length and frailty were observed to be associated with aging. Whether and to what extent telomere length is related to frailty is essentially unknown. In this cross-sectional analysis of baseline data of 3537 community-dwelling adults aged 50 to 75 years of a large German cohort study, we assessed the hypothesis that shorter telomere length might be a biological marker for frailty. Using whole blood DNA we examined mean telomere repeat copy to single gene copy number (T/S ratio) using quantitative PCR. Construction of a frailty index (FI) was based on a deficit accumulation approach, which quantifies frailty as ratio of the deficits present divided by the total number of deficits considered. Mean FI was determined according to age by tertiles of T/S ratio. Furthermore, we used correlation analyses stratified for gender and age groups to examine the association of the T/S ratio with frailty. Mean FI value was similar across tertiles of the T/S ratio (0.24±0.14, 0.24±0.14 and 0.23±0.14, respectively (p=0.09)), and FI and the T/S ratio were uncorrelated in gender- and age-specific analyses. In conclusion, T/S ratio and frailty were unrelated in this large sample of older adults. T/S ratio may therefore not be a meaningful biological marker for frailty.

  18. Inproved grade length limitation of freeways

    Institute of Scientific and Technical Information of China (English)

    XING En-hui; PEI Yu-long

    2006-01-01

    A method of ascertaining grade length limitation of freeways in mountain terrain is presented. The relationship models between 15th percentile speeds and grades were built through the surveys and analyses of operation speeds on 7 typical sections of 3 freeways in mountain terrain. Using 15th percentile and 85th percentile as speed limitations, the methods of determining admitted velocities were put forward according to the grades. Deceleration distances of longitudinal slopeways were analyzed utilizing the theories of vehicle. According to the results of analysis, grade length limitation was loosed. Finally the values of grade length limitation for freeways were put forward. The results could be used as references for freeway design.

  19. Scattering lengths of calcium and barium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Dammalapati, U.; Willmann, L.; Knoop, S. [Kernfysisch Versneller Instituut (KVI), University of Groningen, Zernikelaan 25, 9747 AA Groningen (Netherlands); LaserLaB Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam (Netherlands)

    2011-11-15

    We have calculated the s-wave scattering length of all the even isotopes of calcium (Ca) and barium (Ba) in order to investigate the prospect of Bose-Einstein condensation (BEC). For Ca we have used an accurate molecular potential based on detailed spectroscopic data. Our calculations show that Ca does not provide other isotopes alternative to the recently Bose condensed {sup 40}Ca that suffers strong losses because of a very large scattering length. For Ba we show by using a model potential that the even isotopes cover a broad range of scattering lengths, opening the possibility of BEC for at least one of the isotopes.

  20. The tree length of an evolving coalescent

    CERN Document Server

    Pfaffelhuber, Peter; Weisshaupt, Heinz

    2009-01-01

    A well-established model for the genealogy of a large population in equilibrium is Kingman's coalescent. For the population together with its genealogy evolving in time, this gives rise to a time-stationary tree-valued process. We study the sum of the branch lengths, briefly denoted as tree length, and prove that the (suitably compensated) sequence of tree length processes converges, as the population size tends to infinity, to a limit process with cadlag paths, infinite infinitesimal variance, and a Gumbel distribution as its equilibrium.

  1. Stylish lengths: Mate choice in flowers

    Indian Academy of Sciences (India)

    B T Ramesha; M D Yetish; G Ravikanth; K N Ganeshaiah; Jaboury Ghazoul; R Uma Shaanker

    2011-06-01

    The styles of flowers may represent an arena for pollen competition in the race to fertilize ovules. Accordingly, selection should favour a longer ‘race’ to better discriminate among variable pollen by increasing style length. Sampling across a taxonomically diverse range of wild and outcrossed species, we found that the distribution of style lengths within plants were skewed towards longer styles, as predicted. In self-pollinated domesticated species, where discrimination among pollen is less important, we found no such pattern. We conclude that style length is under directional selection towards longer styles as a mechanism for mate choice among pollen of variable quality.

  2. Bunch Length Measurements in SPEAR3

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, W.J.; Fisher, A.; Huang, X.; Safranek, J.; Sebek, J.; /SLAC; Lumpkin, A.; /Argonne; Sannibale, F.; /LBL, Berkeley; Mok, W.; /Unlisted

    2007-11-28

    A series of bunch length measurements were made in SPEAR3 for two different machine optics. In the achromatic optics the bunch length increases from the low-current value of 16.6ps rms to about 30ps at 25ma/bunch yielding an inductive impedance of -0.17{Omega}. Reducing the momentum compaction factor by a factor of {approx}60 [1] yields a low-current bunch length of {approx}4ps rms. In this paper we review the experimental setup and results.

  3. Carbon Monoxide Mixing Ratio System

    Data.gov (United States)

    Oak Ridge National Laboratory — The Southern Great Plains (SGP) Carbon Monoxide (CO) system provides high-precision atmospheric concentration measurements of CO mixing ratio (ppbv dry air) every 10...

  4. Optimal length of capacitive-discharge and glow-discharge excilamps

    Science.gov (United States)

    Boichenko, A. M.; Erofeev, M. V.; Sosnin, E. A.; Tarasenko, V. F.; Yakovlenko, S. I.

    2007-06-01

    The optimal tube length of capacitive-discharge and glow-discharge excimer lamps with ring and circular electrodes of equal radii is considered. It is demonstrated that, at the same potential difference between electrodes and their radii, the ratio of the optimal lengths of the tubes with circular and ring electrodes depends on width L of the ring electrodes. The ratio of the lengths decreases with decreasing L. A relationship between the tube length and radius, the width of ring electrodes, and the minimum voltage at the tube that provide for an approximately uniform glow of the discharge column in the presence of voltage pulses with opposite polarities at the electrodes is derived.

  5. Pressure Ratio to Thermal Environments

    Science.gov (United States)

    Lopez, Pedro; Wang, Winston

    2012-01-01

    A pressure ratio to thermal environments (PRatTlE.pl) program is a Perl language code that estimates heating at requested body point locations by scaling the heating at a reference location times a pressure ratio factor. The pressure ratio factor is the ratio of the local pressure at the reference point and the requested point from CFD (computational fluid dynamics) solutions. This innovation provides pressure ratio-based thermal environments in an automated and traceable method. Previously, the pressure ratio methodology was implemented via a Microsoft Excel spreadsheet and macro scripts. PRatTlE is able to calculate heating environments for 150 body points in less than two minutes. PRatTlE is coded in Perl programming language, is command-line-driven, and has been successfully executed on both the HP and Linux platforms. It supports multiple concurrent runs. PRatTlE contains error trapping and input file format verification, which allows clear visibility into the input data structure and intermediate calculations.

  6. 西藏藏族学生手长、掌长、指长与身高的关系%THE RELATIONSHIP BETWEEN BODY HEIGHT AND HAND LENGTH,METACARPAL LENGTH AND FINGER LENGTH IN TIBETAN STUDENTS OF XIZANG

    Institute of Scientific and Technical Information of China (English)

    肖艳杰; 吴东妮; 李志强; 席焕久

    2011-01-01

    [Objective] To investigate the relationship between the body height and the hand length, the metacarpal length and the finger length in Tibetan students of Xizang, so it could provide reference for the study of anthropology, ethnology, forensic medicine and clinical medicine. [Methods] The body height, the hand length, the metacarpal length and the finger length of 2 537 Tibetan students aged 7-18 were measured and the results were statistical analysis. [ Results] The mean values of the hand length, the metacarpal length and the finger length, as well as the correlation coefficient and the ratio between them and the body height were calculated out. The regression equations of calculated body height were obtained. [CortClusionj The hand length, the metacarpal length and the finger length have high correlation with the body height and the ratio are fixed. The regression equations can be used to calculate the body height in Tibetan students.%[目的]探讨藏族学生手长、掌长、中指长与身高的关系,为人类学、民族学、法医学及临床医学研究积累资料.[方法]以藏族7~18岁中小学生共2 537人为研究对象,测量其手长、掌长、中指长和身高并进行统计学分析.[结果]计算出手长、掌长、中指长的均数值及其与身高的相关系数、与身高的比值并推算出预测身高的回归方程.[结论]手长、掌长、中指长与身高呈显著正相关且与身高的比值不随年龄变化,所得回归方程可用于推算藏族学生身高.

  7. CPS Trawl Life History Length Frequency Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Length distribution of a subset of individuals from a species (mainly non-target) caught during SWFSC-FRD fishery independent trawl surveys of coastal pelagic...

  8. Diffusion length and resistivity distribution characteristics of silicon wafer by photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Baek, Dohyun; Lee, Jaehyeong; Choi, Byoungdeog, E-mail: bdchoi@skku.edu

    2014-10-15

    Highlights: • Analytical photoluminescence efficiency calculation and PL intensity ratio method are developed. • Wafer resistivity and diffusion length characteristics are investigated by PL intensity ratio. • PL intensity is well correlated with resistivity, diffusion length or defect density on wafer measurement. - Abstract: Photoluminescence is a convenient, contactless method to characterize semiconductors. Its use for room-temperature silicon characterization has only recently been implemented. We have developed the PL efficiency theory as a function of substrate doping densities, bulk trap density, photon flux density, and reflectance and compared it with experimental data initially for bulk Si wafers. New developed PL intensity ratio method is able to predict the silicon wafer properties, such as doping densities, minority carrier diffusion length and bulk trap density.

  9. Second-to-fourth digit ratio related to verbal and numerical intelligence and the big five

    NARCIS (Netherlands)

    Luxen, M.F.; Buunk, Abraham (Bram)

    2005-01-01

    Androgens influence individual differences in a predictable way: they "masculinise" people. The ratio of index finger length to ring finger length (2D:4D) is an index of prenatal androgen exposure. We related 213:413 to Verbal Intelligence, Numerical Intelligence and the Big Five personality

  10. Second-to-fourth digit ratio related to verbal and numerical intelligence and the big five

    NARCIS (Netherlands)

    Luxen, M.F.; Buunk, Abraham (Bram)

    2005-01-01

    Androgens influence individual differences in a predictable way: they "masculinise" people. The ratio of index finger length to ring finger length (2D:4D) is an index of prenatal androgen exposure. We related 213:413 to Verbal Intelligence, Numerical Intelligence and the Big Five personality dimensi

  11. Sex-specific relationship between digit ratio (2D : 4D) and romantic jealousy

    NARCIS (Netherlands)

    Park, Justin H.; Wieling, Martijn B.; Buunk, Abraham P.; Massar, Karlijn

    2008-01-01

    The ratio of index finger length to ring finger length (2D:D4) is an index of prenatal androgen exposure. In a study with 71 female and 52 male undergraduate students, we assessed the relationship between 2D:D4 and jealousy with respect to various dimensions of rival characteristics. Following the p

  12. Sex-specific relationship between digit ratio (2D : 4D) and romantic jealousy

    NARCIS (Netherlands)

    Park, Justin H.; Wieling, Martijn B.; Buunk, Abraham P.; Massar, Karlijn

    The ratio of index finger length to ring finger length (2D:D4) is an index of prenatal androgen exposure. In a study with 71 female and 52 male undergraduate students, we assessed the relationship between 2D:D4 and jealousy with respect to various dimensions of rival characteristics. Following the

  13. Length and coverage of inhibitory decision rules

    KAUST Repository

    Alsolami, Fawaz

    2012-01-01

    Authors present algorithms for optimization of inhibitory rules relative to the length and coverage. Inhibitory rules have a relation "attribute ≠ value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. Paper contains also comparison of length and coverage of inhibitory rules constructed by a greedy algorithm and by the dynamic programming algorithm. © 2012 Springer-Verlag.

  14. Process for fabricating continuous lengths of superconductor

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    1998-01-01

    A process for manufacturing a superconductor. The process is accomplished by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon, overlaying a continuous length of a second substrate ribbon on said first substrate ribbon, and applying sufficient pressure to form a bound layered superconductor precursor between said first substrate ribbon and said second substrates ribbon. The layered superconductor precursor is then heat treated to form a super conductor layer.

  15. Fragment Length of Circulating Tumor DNA.

    Directory of Open Access Journals (Sweden)

    Hunter R Underhill

    2016-07-01

    Full Text Available Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively. Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively. Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

  16. Fragment Length of Circulating Tumor DNA.

    Science.gov (United States)

    Underhill, Hunter R; Kitzman, Jacob O; Hellwig, Sabine; Welker, Noah C; Daza, Riza; Baker, Daniel N; Gligorich, Keith M; Rostomily, Robert C; Bronner, Mary P; Shendure, Jay

    2016-07-01

    Malignant tumors shed DNA into the circulation. The transient half-life of circulating tumor DNA (ctDNA) may afford the opportunity to diagnose, monitor recurrence, and evaluate response to therapy solely through a non-invasive blood draw. However, detecting ctDNA against the normally occurring background of cell-free DNA derived from healthy cells has proven challenging, particularly in non-metastatic solid tumors. In this study, distinct differences in fragment length size between ctDNAs and normal cell-free DNA are defined. Human ctDNA in rat plasma derived from human glioblastoma multiforme stem-like cells in the rat brain and human hepatocellular carcinoma in the rat flank were found to have a shorter principal fragment length than the background rat cell-free DNA (134-144 bp vs. 167 bp, respectively). Subsequently, a similar shift in the fragment length of ctDNA in humans with melanoma and lung cancer was identified compared to healthy controls. Comparison of fragment lengths from cell-free DNA between a melanoma patient and healthy controls found that the BRAF V600E mutant allele occurred more commonly at a shorter fragment length than the fragment length of the wild-type allele (132-145 bp vs. 165 bp, respectively). Moreover, size-selecting for shorter cell-free DNA fragment lengths substantially increased the EGFR T790M mutant allele frequency in human lung cancer. These findings provide compelling evidence that experimental or bioinformatic isolation of a specific subset of fragment lengths from cell-free DNA may improve detection of ctDNA.

  17. Derived length for arbitrary topological spaces

    Directory of Open Access Journals (Sweden)

    A. J. Jayanthan

    1992-01-01

    Full Text Available The notion of derived length is as old as that of ordinal numbers itself. It is also known as the Cantor-Bendixon length. It is defined only for dispersed (that is scattered spaces. In this paper this notion has been extended in a natural way for all topological spaces such that all its pleasing properties are retained. In this process we solve a problem posed by V. Kannan. ([1] Page 158.

  18. RUNX2 tandem repeats and the evolution of facial length in placental mammals

    Directory of Open Access Journals (Sweden)

    Pointer Marie A

    2012-06-01

    Full Text Available Abstract Background When simple sequence repeats are integrated into functional genes, they can potentially act as evolutionary ‘tuning knobs’, supplying abundant genetic variation with minimal risk of pleiotropic deleterious effects. The genetic basis of variation in facial shape and length represents a possible example of this phenomenon. Runt-related transcription factor 2 (RUNX2, which is involved in osteoblast differentiation, contains a functionally-important tandem repeat of glutamine and alanine amino acids. The ratio of glutamines to alanines (the QA ratio in this protein seemingly influences the regulation of bone development. Notably, in domestic breeds of dog, and in carnivorans in general, the ratio of glutamines to alanines is strongly correlated with facial length. Results In this study we examine whether this correlation holds true across placental mammals, particularly those mammals for which facial length is highly variable and related to adaptive behavior and lifestyle (e.g., primates, afrotherians, xenarthrans. We obtained relative facial length measurements and RUNX2 sequences for 41 mammalian species representing 12 orders. Using both a phylogenetic generalized least squares model and a recently-developed Bayesian comparative method, we tested for a correlation between genetic and morphometric data while controlling for phylogeny, evolutionary rates, and divergence times. Non-carnivoran taxa generally had substantially lower glutamine-alanine ratios than carnivorans (primates and xenarthrans with means of 1.34 and 1.25, respectively, compared to a mean of 3.1 for carnivorans, and we found no correlation between RUNX2 sequence and face length across placental mammals. Conclusions Results of our diverse comparative phylogenetic analyses indicate that QA ratio does not consistently correlate with face length across the 41 mammalian taxa considered. Thus, although RUNX2 might function as a ‘tuning knob’ modifying face

  19. RUNX2 tandem repeats and the evolution of facial length in placental mammals.

    Science.gov (United States)

    Pointer, Marie A; Kamilar, Jason M; Warmuth, Vera; Chester, Stephen G B; Delsuc, Frédéric; Mundy, Nicholas I; Asher, Robert J; Bradley, Brenda J

    2012-06-28

    When simple sequence repeats are integrated into functional genes, they can potentially act as evolutionary 'tuning knobs', supplying abundant genetic variation with minimal risk of pleiotropic deleterious effects. The genetic basis of variation in facial shape and length represents a possible example of this phenomenon. Runt-related transcription factor 2 (RUNX2), which is involved in osteoblast differentiation, contains a functionally-important tandem repeat of glutamine and alanine amino acids. The ratio of glutamines to alanines (the QA ratio) in this protein seemingly influences the regulation of bone development. Notably, in domestic breeds of dog, and in carnivorans in general, the ratio of glutamines to alanines is strongly correlated with facial length. In this study we examine whether this correlation holds true across placental mammals, particularly those mammals for which facial length is highly variable and related to adaptive behavior and lifestyle (e.g., primates, afrotherians, xenarthrans). We obtained relative facial length measurements and RUNX2 sequences for 41 mammalian species representing 12 orders. Using both a phylogenetic generalized least squares model and a recently-developed Bayesian comparative method, we tested for a correlation between genetic and morphometric data while controlling for phylogeny, evolutionary rates, and divergence times. Non-carnivoran taxa generally had substantially lower glutamine-alanine ratios than carnivorans (primates and xenarthrans with means of 1.34 and 1.25, respectively, compared to a mean of 3.1 for carnivorans), and we found no correlation between RUNX2 sequence and face length across placental mammals. Results of our diverse comparative phylogenetic analyses indicate that QA ratio does not consistently correlate with face length across the 41 mammalian taxa considered. Thus, although RUNX2 might function as a 'tuning knob' modifying face length in carnivorans, this relationship is not conserved across

  20. Reduced fetal telomere length in gestational diabetes.

    Directory of Open Access Journals (Sweden)

    Jian Xu

    Full Text Available Gestational diabetes mellitus (GDM is an important complication of pregnancy that poses significant threats to women and their offspring. Telomere length shortens as cellular damage increases and is associated with metabolic diseases. Telomere length in fetal leucocytes was determined in 82 infants of women with GDM (N = 82 and 65 normal pregnant women (N = 65. Women with preeclampsia (N = 45 and gestational hypertension (N = 23 were also studied. In the GDM group, telomere length was significantly shorter than normal pregnancy (P = 0.028, but there were no significant differences in fetal telomere length between preeclampsia and normal pregnancy (P = 0.841 and between gestational hypertension and normal pregnancy (P = 0.561. Regression analysis revealed that fetal telomere length was significantly associated with intrauterine exposure to GDM (P = 0.027 after adjustment for maternal age, gestational age at delivery, birth weight and fetal gender. Shortened telomere length may increase the risk of metabolic diseases in adulthood of GDM offspring.

  1. Classifying stages of third molar development: crown length as a predictor for the mature root length.

    Science.gov (United States)

    Altalie, Salem; Thevissen, Patrick; Willems, Guy

    2015-01-01

    Multiple tooth development staging techniques were reported based on arbitrarily set borderlines between succeeding stages. Anatomic tooth features or predictions of future tooth part dimensions were described to identify the thresholds between the established stages. The need to predict mature tooth dimensions, while the tooth considered is still in development, is a drawback to use this staging technique for dental age estimations. Using the fully mature crown length as a predictor for the future root length could provide a tool for undisputable staging. The aim of this study was first to measure the crown and root length of fully mature third molars and second to investigate whether the crown length could be used as a predictor of the root length, in order to classify the observed root length as a proportion of the future mature root. The crown and root lengths of all present third molars were digitally measured on dental panoramic radiographs of 1,000 subjects. The included subjects were equally distributed in gender, and their age ranged between 22 and 40 years. Two occlusal borders, the cement enamel junction and the root apices, were defined as landmarks for standardized measurements. Regression models with root length as response and crown length as predictor were established and revealed low R (2) and high RMSE values. Due to the small explained variance by the prediction models and the high variation in prediction errors, the observed crown length cannot be used to predict the final root length of a developing third molar.

  2. The effect of muscle length on force depression after active shortening in soleus muscle of mice.

    Science.gov (United States)

    Van Noten, Pieter; Van Leemputte, Marc

    2011-07-01

    Isometric muscle force after active shortening is reduced [force depression (FD)]. The mechanism is incompletely understood but work delivered during shortening has been suggested to be the main determinant of FD. However, whether muscle length affects the sensitivity of FD to work is unknown, although this information might add to the understanding of the phenomenon. The aim of this study is to investigate the length dependence of the FD/work ratio (Q). Therefore, isometric force production (ISO) of 10 incubated mouse soleus muscles was compared to isometric force after 0.6, 1.2, and 2.4 mm shortening (IAS) at different end lengths ranging from L(0) - 3 to L(0) + 1.8 mm in steps of 0.6 mm. FD was calculated as the force difference between an ISO and IAS contraction at the same activation time (6 s) and end length. We confirm the strong relation between FD and work at L(0) (R² = 0.92) and found that FD is length dependent with a maximum of 8.8 ± 0.3% at L(0) + 1.2 mm for 0.6 mm shortening amplitude. Q was only constant for short muscle lengths (muscle length. The observed length dependence of Q indicates that FD is not only determined by work produced during shortening but also by a length-dependent factor, possibly actin compliance, which should be incorporated in any mechanism explaining FD.

  3. Ultrasonic Evaluation of the Lens Thickness to Axial Length Factor in Primary Closure Angle Glaucoma

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    Ultrasonic biometry was done in 232 normal eyes and 138 eyes with primary angle closure glaucoma (ACG), using Ultrascan Digital B System IV (10 MHz). The ratio between the lens thickness and the axial length (lens thickness to axial length factor, LAF) was evaluated as a biometric index for assessing the eye with primary ACG in Chinese. LAF of 2.00 was found to be ideal point of demarcation between ACG and normal eyes (i.e., lens thickness equals to 1/5 of axial length). It appears that LAF is helpful i...

  4. Shunting ratios for MHD flows

    Energy Technology Data Exchange (ETDEWEB)

    Birzvalk, Yu.

    1978-01-01

    The shunting ratio and the local shunting ratio, pertaining to currents induced by a magnetic field in a flow channel, are properly defined and systematically reviewed on the basis of the Lagrange criterion. Their definition is based on the energy balance and related to dimensionless parameters characterizing an MHD flow, these parameters evolving from the Hartmann number and the hydrodynamic Reynolds number as well as the magnetic Reynolds number, and the Lundquist number. These shunting ratios, of current density in the core of a stream (uniform) or equivalent mean current density to the short-circuit (maximum) current density, are given here for a slot channel with nonconducting or conducting walls, for a conduction channel with heavy side rails, and for an MHD-flow around bodies. 5 references, 1 figure.

  5. Mixing properties of coaxial jets with large velocity ratios and large inverse density ratios

    Science.gov (United States)

    Alexander Schumaker, S.; Driscoll, James F.

    2012-05-01

    An experimental study was conducted to better understand the mixing properties of coaxial jets as several parameters were systematically varied, including the velocity ratio, density ratio, and the Reynolds number. Diameters of the inner and outer jet were also varied. Coaxial jets are commonly used to mix fluids due to the simplicity of their geometry and the rapid mixing that they provide. A measure of the overall mixing efficiency is the stoichiometric mixing length (Ls), which is the distance along the jet centerline where the two fluids have mixed to some desired concentration, which was selected to be the stoichiometric concentration for H2/O2 and CH4/O2 in this case. For 56 cases, the profiles of mean mixture fraction, rms mixture fraction fluctuations (unmixedness), and Ls were measured using acetone planar laser induced fluorescence diagnostics. Results were compared to three mixing models. The entrainment model of Villermaux and Rehab showed good agreement with the data, indicating that the proper non-dimensional scaling parameter is the momentum flux ratio M. The work extends the existing database of coaxial jet scalar mixing properties because it considers the specific regime of large values of both the velocity ratio and the inverse density ratio, which is the regime in which rocket injectors operate. Also the work focuses on the mixing up to Ls where previous work focused on the mixing up to the end of the inner core. The Reynolds numbers achieved for a number of cases were considerably larger than previous gas mixing studies, which insures that the jet exit boundary conditions are fully turbulent.

  6. The acoustics of short circular holes with finite expansion ratio

    Science.gov (United States)

    Yang, Dong; Morgans, Aimee

    2016-11-01

    The acoustic response of a circular hole with mean flow passing through it is highly relevant to Helmholtz resonators, fuel injectors, perforated liners, perforated plates and many other engineering applications. Analytical models for the acoustic response of these holes often ignore the impact of a finite expansion ratio either side, or account for it simply by adding an end mass inertial correction derived from the no mean flow assumption. The vortex-sound interaction within a short hole has been recently shown to strongly affect the acoustic response in the low frequency region. The present study uses an analytical model based on the Green's function method to investigate how the expansion ratios either side of a short hole affect the vortex-sound interaction within it - something neglected by previous models. This model is then incorporated into a Helmholtz resonator model, allowing us to consider the effect of a finite neck-to-cavity expansion ratio and the vortex-sound interaction within the finite length neck. Large resistance and acoustic energy absorption performance variations are seen even for small changes in the resonator neck length. Reducing the neck-to-cavity expansion ratio is found to decrease the resonator's sound absorption when the expansion ratio is low. CSC-Imperial PhD Scholarship; ERC Starting Grant, ACOULOMODE (2013-18).

  7. Incentive Ratios of Fisher Markets

    DEFF Research Database (Denmark)

    Chen, Ning; Deng, Xuaitue; Zhang, Hongyang

    2012-01-01

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

  8. Ratio Bias and Policy Preferences

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Tue

    2016-01-01

    Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...... is a general tendency to focus on numerators and pay insufficient attention to denominators in ratios. Using a population-based survey experiment, I demonstrate how differently framed but logically equivalent representations of the exact same numerical value can have large effects on citizens’ preferences...

  9. Leukocyte Telomere Length in Healthy Caucasian and African-American Adolescents : Relationships with Race, Sex, Adiposity, Adipokines, and Physical Activity

    NARCIS (Netherlands)

    Zhu, Haidong; Wang, Xiaoling; Gutin, Bernard; Davis, Catherine L.; Keeton, Daniel; Thomas, Jeffrey; Stallmann-Jorgensen, Inger; Mooken, Grace; Bundy, Vanessa; Snieder, Harold; van der Harst, Pim; Dong, Yanbin

    2011-01-01

    Objective To examine the relationships of race, sex, adiposity, adipokines, and physical activity to telomere length in adolescents. Study design Leukocyte telomere length (T/S ratio) was assessed cross-sectionally in 667 adolescents (aged 14-18 years; 48% African-Americans; 51% girls) using a quant

  10. SEXUAL DIMORPHISM OF MAXIMUM FEMORAL LENGTH

    Directory of Open Access Journals (Sweden)

    Pandya A M

    2011-04-01

    Full Text Available Sexual identification from the skeletal parts has medico legal and anthropological importance. Present study aims to obtain values of maximum femoral length and to evaluate its possible usefulness in determining correct sexual identification. Study sample consisted of 184 dry, normal, adult, human femora (136 male & 48 female from skeletal collections of Anatomy department, M. P. Shah Medical College, Jamnagar, Gujarat. Maximum length of femur was considered as maximum vertical distance between upper end of head of femur and the lowest point on femoral condyle, measured with the osteometric board. Mean Values obtained were, 451.81 and 417.48 for right male and female, and 453.35 and 420.44 for left male and female respectively. Higher value in male was statistically highly significant (P< 0.001 on both sides. Demarking point (D.P. analysis of the data showed that right femora with maximum length more than 476.70 were definitely male and less than 379.99 were definitely female; while for left bones, femora with maximum length more than 484.49 were definitely male and less than 385.73 were definitely female. Maximum length identified 13.43% of right male femora, 4.35% of right female femora, 7.25% of left male femora and 8% of left female femora. [National J of Med Res 2011; 1(2.000: 67-70

  11. Explaining the length threshold of polyglutamine aggregation

    Science.gov (United States)

    De Los Rios, Paolo; Hafner, Marc; Pastore, Annalisa

    2012-06-01

    The existence of a length threshold, of about 35 residues, above which polyglutamine repeats can give rise to aggregation and to pathologies, is one of the hallmarks of polyglutamine neurodegenerative diseases such as Huntington’s disease. The reason why such a minimal length exists at all has remained one of the main open issues in research on the molecular origins of such classes of diseases. Following the seminal proposals of Perutz, most research has focused on the hunt for a special structure, attainable only above the minimal length, able to trigger aggregation. Such a structure has remained elusive and there is growing evidence that it might not exist at all. Here we review some basic polymer and statistical physics facts and show that the existence of a threshold is compatible with the modulation that the repeat length imposes on the association and dissociation rates of polyglutamine polypeptides to and from oligomers. In particular, their dramatically different functional dependence on the length rationalizes the very presence of a threshold and hints at the cellular processes that might be at play, in vivo, to prevent aggregation and the consequent onset of the disease.

  12. Delayed feedback model of axonal length sensing.

    Science.gov (United States)

    Karamched, Bhargav R; Bressloff, Paul C

    2015-05-05

    A fundamental question in cell biology is how the sizes of cells and organelles are regulated at various stages of development. Size homeostasis is particularly challenging for neurons, whose axons can extend from hundreds of microns to meters (in humans). Recently, a molecular-motor-based mechanism for axonal length sensing has been proposed, in which axonal length is encoded by the frequency of an oscillating retrograde signal. In this article, we develop a mathematical model of this length-sensing mechanism in which advection-diffusion equations for bidirectional motor transport are coupled to a chemical signaling network. We show that chemical oscillations emerge due to delayed negative feedback via a Hopf bifurcation, resulting in a frequency that is a monotonically decreasing function of axonal length. Knockdown of either kinesin or dynein causes an increase in the oscillation frequency, suggesting that the length-sensing mechanism would produce longer axons, which is consistent with experimental findings. One major prediction of the model is that fluctuations in the transport of molecular motors lead to a reduction in the reliability of the frequency-encoding mechanism for long axons. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  13. Tactile length contraction as Bayesian inference.

    Science.gov (United States)

    Tong, Jonathan; Ngo, Vy; Goldreich, Daniel

    2016-08-01

    To perceive, the brain must interpret stimulus-evoked neural activity. This is challenging: The stochastic nature of the neural response renders its interpretation inherently uncertain. Perception would be optimized if the brain used Bayesian inference to interpret inputs in light of expectations derived from experience. Bayesian inference would improve perception on average but cause illusions when stimuli violate expectation. Intriguingly, tactile, auditory, and visual perception are all prone to length contraction illusions, characterized by the dramatic underestimation of the distance between punctate stimuli delivered in rapid succession; the origin of these illusions has been mysterious. We previously proposed that length contraction illusions occur because the brain interprets punctate stimulus sequences using Bayesian inference with a low-velocity expectation. A novel prediction of our Bayesian observer model is that length contraction should intensify if stimuli are made more difficult to localize. Here we report a tactile psychophysical study that tested this prediction. Twenty humans compared two distances on the forearm: a fixed reference distance defined by two taps with 1-s temporal separation and an adjustable comparison distance defined by two taps with temporal separation t ≤ 1 s. We observed significant length contraction: As t was decreased, participants perceived the two distances as equal only when the comparison distance was made progressively greater than the reference distance. Furthermore, the use of weaker taps significantly enhanced participants' length contraction. These findings confirm the model's predictions, supporting the view that the spatiotemporal percept is a best estimate resulting from a Bayesian inference process.

  14. Factors That Influence Primary Cilium Length

    Directory of Open Access Journals (Sweden)

    Miyoshi,Ko

    2011-10-01

    Full Text Available Almost all mammalian cells carry one primary cilium that functions as a biosensor for chemical and mechanical stimuli. Genetic damages that compromise cilia formation or function cause a spectrum of disorders referred to as ciliapathies. Recent studies have demonstrated that some pharmacological agents and extracellular environmental changes can alter primary cilium length. Renal injury is a well-known example of an environmental insult that triggers cilia length modification. Lithium treatment causes primary cilia to extend in several cell types including neuronal cells;this phenomenon is likely independent of glycogen synthase kinase-3β inhibition. In renal epithelial cell lines, deflection of the primary cilia by fluid shear shortens them by reducing the intracellular cyclic AMP level, leading to a subsequent decrease in mechanosensitivity to fluid shear. Primary cilium length is also influenced by the dynamics of actin filaments and microtubules through the levels of soluble tubulin in the cytosol available for primary cilia extension. Thus, mammalian cells can adapt to the extracellular environment by modulating the primary cilium length, and this feedback system utilizing primary cilia might exist throughout the mammalian body. Further investigation is required concerning the precise molecular mechanisms underlying the control of primary cilium length in response to environmental factors.

  15. Metastable neon collisions: anisotropy and scattering length

    CERN Document Server

    Mogendorff, V P; Verhaar, B J; Beijerinck, H C W

    2003-01-01

    In this paper we investigate the effective scattering length $a$ of spin-polarized Ne*. Due to its anisotropic electrostatic interaction, its scattering length is determined by five interaction potentials instead of one, even in the spin-polarized case, a unique property among the Bose condensed species and candidates. Because the interaction potentials of Ne* are not known accurately enough to predict the value of the scattering length, we investigate the behavior of $a$ as a function of the five phase integrals corresponding to the five interaction potentials. We find that the scattering length has five resonances instead of only one and cannot be described by a simple gas-kinetic approach or the DIS approximation. However, the probability for finding a positive or large value of the scattering length is not enhanced compared to the single potential case. The complex behavior of $a$ is studied by comparing a quantum mechanical five-channel numerical calculation to simpler two-channel models. We find that th...

  16. Ratio Bias and Policy Preferences

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Tue

    2016-01-01

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

  17. Gender Ratios for Reading Difficulties

    Science.gov (United States)

    Hawke, Jesse L.; Olson, Richard K.; Willcut, Erik G.; Wadsworth, Sally J.; DeFries, John C.

    2009-01-01

    The prevalence of reading difficulties is typically higher in males than females in both referred and research-identified samples, and the ratio of males to females is greater in more affected samples. To explore possible gender differences in reading performance, we analysed data from 1133 twin pairs in which at least one member of each pair had…

  18. Optical Tracking Measurement on Vortex Induced Vibration of Flexible Riser with Short-Length Buoyance Module

    Science.gov (United States)

    Fan, Dixia; Du, Honglin; Triantafyllou, Michael

    2016-11-01

    We address experimentally the vortex induced vibrations (VIV) of long flexible cylinders. We employ optical tracking, using an array of high speed cameras. Compared to strain gauges and accelerometers, this non-intrusive approach, allows direct measurement of the flexible cylinder displacement with far denser spatial distribution. The measurements reveal essential features of flexible cylinder VIV, including complex geometries such as cylinders containing short-length buoyancy modules, with module to cylinder diameter ratio of 1:3.2 and module to bare cylinder length ratio of 1:1. The experiments are conducted with aspect ratio of 170 and 3 different coverage ratios, of 100%, 50% and 20%. The measurements demonstrate bi-frequency response due to excitation from both buoyancy module and bare cylinder, at low Strouhal number, down to values of 0.08, and the generation of traveling wave patterns.

  19. Length and distance on a quantum space

    CERN Document Server

    Martinetti, Pierre

    2012-01-01

    This contribution is an introduction to the metric aspect of noncommutative geometry, with emphasize on the Moyal plane. Starting by questioning "how to define a standard meter in a space whose coordinates no longer commute?", we list several recent results regarding Connes's spectral distance calculated between eigenstates of the quantum harmonic oscillator arXiv:0912.0906, as well as between coherent states arXiv:1110.6164. We also question the difference (which remains hidden in the commutative case) between the spectral distance and the notion of quantum length inherited from the length operator defined in various models of noncommutative space-time (DFR and \\theta-Minkowski). We recall that a standard procedure in noncommutative geometry, consisting in doubling the spectral triple, allows to fruitfully confront the spectral distance with the quantum length. Finally we refine the idea of discrete vs. continuous geodesics in the Moyal plane, introduced in arXiv:1106.0261.

  20. Minimal Length Scale Scenarios for Quantum Gravity

    Directory of Open Access Journals (Sweden)

    Sabine Hossenfelder

    2013-01-01

    Full Text Available We review the question of whether the fundamental laws of nature limit our ability to probe arbitrarily short distances. First, we examine what insights can be gained from thought experiments for probes of shortest distances, and summarize what can be learned from different approaches to a theory of quantum gravity. Then we discuss some models that have been developed to implement a minimal length scale in quantum mechanics and quantum field theory. These models have entered the literature as the generalized uncertainty principle or the modified dispersion relation, and have allowed the study of the effects of a minimal length scale in quantum mechanics, quantum electrodynamics, thermodynamics, black-hole physics and cosmology. Finally, we touch upon the question of ways to circumvent the manifestation of a minimal length scale in short-distance physics.

  1. Minimal Length Scale Scenarios for Quantum Gravity.

    Science.gov (United States)

    Hossenfelder, Sabine

    2013-01-01

    We review the question of whether the fundamental laws of nature limit our ability to probe arbitrarily short distances. First, we examine what insights can be gained from thought experiments for probes of shortest distances, and summarize what can be learned from different approaches to a theory of quantum gravity. Then we discuss some models that have been developed to implement a minimal length scale in quantum mechanics and quantum field theory. These models have entered the literature as the generalized uncertainty principle or the modified dispersion relation, and have allowed the study of the effects of a minimal length scale in quantum mechanics, quantum electrodynamics, thermodynamics, black-hole physics and cosmology. Finally, we touch upon the question of ways to circumvent the manifestation of a minimal length scale in short-distance physics.

  2. Environmental stresses disrupt telomere length homeostasis.

    Directory of Open Access Journals (Sweden)

    Gal Hagit Romano

    Full Text Available Telomeres protect the chromosome ends from degradation and play crucial roles in cellular aging and disease. Recent studies have additionally found a correlation between psychological stress, telomere length, and health outcome in humans. However, studies have not yet explored the causal relationship between stress and telomere length, or the molecular mechanisms underlying that relationship. Using yeast as a model organism, we show that stresses may have very different outcomes: alcohol and acetic acid elongate telomeres, whereas caffeine and high temperatures shorten telomeres. Additional treatments, such as oxidative stress, show no effect. By combining genome-wide expression measurements with a systematic genetic screen, we identify the Rap1/Rif1 pathway as the central mediator of the telomeric response to environmental signals. These results demonstrate that telomere length can be manipulated, and that a carefully regulated homeostasis may become markedly deregulated in opposing directions in response to different environmental cues.

  3. A Contribution to Arc Length Discussion

    Directory of Open Access Journals (Sweden)

    Stephan Egerland

    2015-09-01

    Full Text Available Abstract An investigation was raising the question: "What does 'arc length' mean?" Actually, it is considered expressing a kind of natural relationship between arc voltage and arc column shape. Statements such as "The higher the voltage the longer the arc" or "The arc voltage proves approximately proportional to the arc length", are frequently noticed in this conjunction. However, the author suggests that there is no general possibility of describing 'arc length' over the whole welding process range. Instances are represented in this paper, showing both theoretical attempts of definition and practical observations. This paper intends to contribute to a serious discussion of something trivial, indeed very well-known or used among welding experts, but actually yet hardly understood, at least as when it comes to closer examination

  4. Telomerase activity and telomere length in Daphnia.

    Science.gov (United States)

    Schumpert, Charles; Nelson, Jacob; Kim, Eunsuk; Dudycha, Jeffry L; Patel, Rekha C

    2015-01-01

    Telomeres, comprised of short repetitive sequences, are essential for genome stability and have been studied in relation to cellular senescence and aging. Telomerase, the enzyme that adds telomeric repeats to chromosome ends, is essential for maintaining the overall telomere length. A lack of telomerase activity in mammalian somatic cells results in progressive shortening of telomeres with each cellular replication event. Mammals exhibit high rates of cell proliferation during embryonic and juvenile stages but very little somatic cell proliferation occurs during adult and senescent stages. The telomere hypothesis of cellular aging states that telomeres serve as an internal mitotic clock and telomere length erosion leads to cellular senescence and eventual cell death. In this report, we have examined telomerase activity, processivity, and telomere length in Daphnia, an organism that grows continuously throughout its life. Similar to insects, Daphnia telomeric repeat sequence was determined to be TTAGG and telomerase products with five-nucleotide periodicity were generated in the telomerase activity assay. We investigated telomerase function and telomere lengths in two closely related ecotypes of Daphnia with divergent lifespans, short-lived D. pulex and long-lived D. pulicaria. Our results indicate that there is no age-dependent decline in telomere length, telomerase activity, or processivity in short-lived D. pulex. On the contrary, a significant age dependent decline in telomere length, telomerase activity and processivity is observed during life span in long-lived D. pulicaria. While providing the first report on characterization of Daphnia telomeres and telomerase activity, our results also indicate that mechanisms other than telomere shortening may be responsible for the strikingly short life span of D. pulex.

  5. Telomerase Activity and Telomere Length in Daphnia

    Science.gov (United States)

    Schumpert, Charles; Nelson, Jacob; Kim, Eunsuk; Dudycha, Jeffry L.; Patel, Rekha C.

    2015-01-01

    Telomeres, comprised of short repetitive sequences, are essential for genome stability and have been studied in relation to cellular senescence and aging. Telomerase, the enzyme that adds telomeric repeats to chromosome ends, is essential for maintaining the overall telomere length. A lack of telomerase activity in mammalian somatic cells results in progressive shortening of telomeres with each cellular replication event. Mammals exhibit high rates of cell proliferation during embryonic and juvenile stages but very little somatic cell proliferation occurs during adult and senescent stages. The telomere hypothesis of cellular aging states that telomeres serve as an internal mitotic clock and telomere length erosion leads to cellular senescence and eventual cell death. In this report, we have examined telomerase activity, processivity, and telomere length in Daphnia, an organism that grows continuously throughout its life. Similar to insects, Daphnia telomeric repeat sequence was determined to be TTAGG and telomerase products with five-nucleotide periodicity were generated in the telomerase activity assay. We investigated telomerase function and telomere lengths in two closely related ecotypes of Daphnia with divergent lifespans, short-lived D. pulex and long-lived D. pulicaria. Our results indicate that there is no age-dependent decline in telomere length, telomerase activity, or processivity in short-lived D. pulex. On the contrary, a significant age dependent decline in telomere length, telomerase activity and processivity is observed during life span in long-lived D. pulicaria. While providing the first report on characterization of Daphnia telomeres and telomerase activity, our results also indicate that mechanisms other than telomere shortening may be responsible for the strikingly short life span of D. pulex. PMID:25962144

  6. Universality of modulation length and time exponents.

    Science.gov (United States)

    Chakrabarty, Saurish; Dobrosavljević, Vladimir; Seidel, Alexander; Nussinov, Zohar

    2012-10-01

    We study systems with a crossover parameter λ, such as the temperature T, which has a threshold value λ(*) across which the correlation function changes from exhibiting fixed wavelength (or time period) modulations to continuously varying modulation lengths (or times). We introduce a hitherto unknown exponent ν(L) characterizing the universal nature of this crossover and compute its value in general instances. This exponent, similar to standard correlation length exponents, is obtained from motion of the poles of the momentum (or frequency) space correlation functions in the complex k-plane (or ω-plane) as the parameter λ is varied. Near the crossover (i.e., for λ→λ(*)), the characteristic modulation wave vector K(R) in the variable modulation length "phase" is related to that in the fixed modulation length "phase" q via |K(R)-q|[proportionality]|T-T(*)|(νL). We find, in general, that ν(L)=1/2. In some special instances, ν(L) may attain other rational values. We extend this result to general problems in which the eigenvalue of an operator or a pole characterizing general response functions may attain a constant real (or imaginary) part beyond a particular threshold value λ(*). We discuss extensions of this result to multiple other arenas. These include the axial next-nearest-neighbor Ising (ANNNI) model. By extending our considerations, we comment on relations pertaining not only to the modulation lengths (or times), but also to the standard correlation lengths (or times). We introduce the notion of a Josephson time scale. We comment on the presence of aperiodic "chaotic" modulations in "soft-spin" and other systems. These relate to glass-type features. We discuss applications to Fermi systems, with particular application to metal to band insulator transitions, change of Fermi surface topology, divergent effective masses, Dirac systems, and topological insulators. Both regular periodic and glassy (and spatially chaotic behavior) may be found in

  7. Aerodynamic Properties of Rough Surfaces with High Aspect-Ratio Roughness Elements: Effect of Aspect Ratio and Arrangements

    Science.gov (United States)

    Sadique, Jasim; Yang, Xiang I. A.; Meneveau, Charles; Mittal, Rajat

    2017-05-01

    We examine the effect of varying roughness-element aspect ratio on the mean velocity distributions of turbulent flow over arrays of rectangular-prism-shaped elements. Large-eddy simulations (LES) in conjunction with a sharp-interface immersed boundary method are used to simulate spatially-growing turbulent boundary layers over these rough surfaces. Arrays of aligned and staggered rectangular roughness elements with aspect ratio >1 are considered. First the temporally- and spatially-averaged velocity profiles are used to illustrate the aspect-ratio effects. For aligned prisms, the roughness length (z_o) and the friction velocity (u_*) increase initially with an increase in the roughness-element aspect ratio, until the values reach a plateau at a particular aspect ratio. The exact value of this aspect ratio depends on the coverage density. Further increase in the aspect ratio changes neither z_o, u_* nor the bulk flow above the roughness elements. For the staggered cases, z_o and u_* continue to increase for the surface coverage density and the aspect ratios investigated. To model the flow response to variations in roughness aspect ratio, we turn to a previously developed phenomenological volumetric sheltering model (Yang et al., in J Fluid Mech 789:127-165, 2016), which was intended for low to moderate aspect-ratio roughness elements. Here, we extend this model to account for high aspect-ratio roughness elements. We find that for aligned cases, the model predicts strong mutual sheltering among the roughness elements, while the effect is much weaker for staggered cases. The model-predicted z_o and u_* agree well with the LES results. Results show that the model, which takes explicit account of the mutual sheltering effects, provides a rapid and reliable prediction method of roughness effects in turbulent boundary-layer flows over arrays of rectangular-prism roughness elements.

  8. PENDULUM WITH LINEAR DAMPING AND VARIABLE LENGTH

    Institute of Scientific and Technical Information of China (English)

    蔡建平; 杨翠红; 李怡平

    2004-01-01

    The methods of multiple scales and approximate potential are used to study pendulums with linear damping and variable length. According to the order of the coefficient of friction compared with that of the slowly varying parameter of length, three different cases are discussed in details. Asymptotic analytical expressions of amplitude, frequency and solution are obtained. The method of approximate potential makes the results effective for large oscillations. A modified multiple scales method is used to get more accurate leading order approximations when the coefficient friction is not small. Comparisons are also made with numerical results to show the efficiency of the present method.

  9. Localization length fluctuation in randomly layered media

    Science.gov (United States)

    Yuan, Haiming; Huang, Feng; Jiang, Xiangqian; Sun, Xiudong

    2016-10-01

    Localization properties of the two-component randomly layered media (RLM) are studied in detail both analytically and numerically. The localization length is found fluctuating around the analytical result obtained under the high-frequency limit. The fluctuation amplitude approaches zero with the increasing of disorder, which is characterized by the distribution width of random thickness. It is also found that the localization length over the mean thickness periodically varies with the distribution center of random thickness. For the multi-component RLM structure, the arrangement of material must be considered.

  10. Isospin odd pi K scattering length

    CERN Document Server

    Schweizer, J

    2005-01-01

    We make use of the chiral two-loop representation of the pi K scattering amplitude [J. Bijnens, P. Dhonte and P. Talavera, JHEP 0405 (2004) 036] to investigate the isospin odd scattering length at next-to-next-to-leading order in the SU(3) expansion. This scattering length is protected against contributions of m_s in the chiral expansion, in the sense that the corrections to the current algebra result are of order M_pi^2. In view of the planned lifetime measurement on pi K atoms at CERN it is important to understand the size of these corrections.

  11. Apparatus for fabricating continuous lengths of superconductor

    Science.gov (United States)

    Kroeger, Donald M.; List, III, Frederick A.

    2002-01-01

    A process and apparatus for manufacturing a superconductor. The process is accomplished by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon, overlaying a continuous length of a second substrate ribbon on said first substrate ribbon, and applying sufficient pressure to form a bound layered superconductor comprising a layer of said superconducting precursor powder between said first substrate ribbon and said second substrates ribbon. The layered superconductor is then heat treated to establish the superconducting phase of said superconductor precursor powder.

  12. Isospin odd {pi}K scattering length

    Energy Technology Data Exchange (ETDEWEB)

    Schweizer, J. [Institut fuer Theoretische Physik, University of Vienna, A-1090 Vienna (Austria)]. E-mail: julia.schweizer@univie.ac.at

    2005-10-13

    We make use of the chiral two-loop representation of the {pi}K scattering amplitude [J. Bijnens, P. Dhonte, P. Talavera, JHEP 0405 (2004) 036] to investigate the isospin odd scattering length at next-to-next-to-leading order in the SU(3) expansion. This scattering length is protected against contributions of m{sub s} in the chiral expansion, in the sense that the corrections to the current algebra result are of order M{sub {pi}}{sup 2}. In view of the planned lifetime measurement on {pi}K atoms at CERN it is important to understand the size of these corrections.

  13. A simple method for focal length measurement

    Science.gov (United States)

    Ma, Hua; Ren, Huan; Zhang, Lin; Shi, Zhengdong; Yuan, Quan; Yang, Yi

    2016-09-01

    A simple method for focal length measurement based on image processing is demonstrated and discussed. The collimated beam, detector, motorized translation stage and computer make up of this test system. The two spots pass through the tested lens is accepted by detector, which is transferred twice by motorized translation stage. By acquired the difference of two spots by image processing, the focal length of the tested lens can be gained. The error sources in the measurement are analyzed. Then the results of experiment show that the relative error was 0.1%. This method can be used in workshop and labs for its convenience and low cost.

  14. Sighting optics including an optical element having a first focal length and a second focal length

    Science.gov (United States)

    Crandall, David Lynn

    2011-08-01

    One embodiment of sighting optics according to the teachings provided herein may include a front sight and a rear sight positioned in spaced-apart relation. The rear sight includes an optical element having a first focal length and a second focal length. The first focal length is selected so that it is about equal to a distance separating the optical element and the front sight and the second focal length is selected so that it is about equal to a target distance. The optical element thus brings into simultaneous focus, for a user, images of the front sight and the target.

  15. Micro precision casting based on investment casting for micro structures with high aspect ratio

    Institute of Scientific and Technical Information of China (English)

    YANG Chuang; LI Bang-sheng; REN Ming-xing; FU Heng-zhi

    2009-01-01

    Microcasting is one of the significant technologies for the production of metallic micro parts with high aspect ratio (ratio of flow length to diameter). A micro precision casting technology based on investment casting using centrifugal method was investigated. The micro parts of Zn-4%Al alloy with an aspect ratio up to 200 was produced at the centrifugal speed of 1 500 r/min and the mold temperature of 270 ℃. The investigations on the relationship between flow length and rotational speed were carried out. For microcasting, the flow length is not only dependent on the centrifugal speed under the constant centrifugal radius, but also on the preheating temperature of mold. The flow length increases as the rotational speed and the mold temperature increase, and is much higher at a mold temperature of 270 ℃ than at other mold temperatures.

  16. Consecutive cervical length measurements as a predictor of preterm cesarean section in complete placenta previa.

    Science.gov (United States)

    Sekiguchi, Atsuko; Nakai, Akihito; Okuda, Naotaka; Inde, Yusuke; Takeshita, Toshiyuki

    2015-01-01

    To evaluate whether consecutive cervical length measurements can predict preterm cesarean section in women with complete placenta previa. Seventy-one women with complete placenta previa were retrospectively categorized into women who delivered preterm due to massive hemorrhage (the preterm cesarean section group, n = 28) and those delivered at term (the control group, n = 43). Maternal characteristics, delivery outcomes, and cervical lengths serially measured at least every 2 weeks from 24 weeks' gestation until delivery were compared. The relationship between cervical length and preterm cesarean section was analyzed. Cervical length gradually decreased with advancing gestational age. After 26 weeks' gestation, this decrease was significantly more rapid in the preterm cesarean section group. Cervical length before cesarean section in the preterm cesarean section group was significantly shorter than that in the control group. Just before cesarean section, 71.4% of the preterm cesarean section group presented with cervical lengths of ≤35 mm, whereas only 34.9% of the control group had cervical lengths of ≤35 mm (odds ratio 4.67, 95% confidence interval 1.66-13.10, p = 0.006). In women with complete placenta previa, decrease in cervical length to ≤35 mm was associated with increased risk of preterm cesarean section due to massive hemorrhage. © 2014 Wiley Periodicals, Inc.

  17. DYNAMIC TEACHING RATIO PEDAGOGIC MODEL

    Directory of Open Access Journals (Sweden)

    Chen Jiaying

    2010-11-01

    Full Text Available This paper outlines an innovative pedagogic model, Dynamic Teaching Ratio (DTR Pedagogic Model, for learning design and teaching strategy aimed at the postsecondary technical education. The model draws on the theory of differential learning, which is widely recognized as an important tool for engaging students and addressing the individual needs of all students. The DTR model caters to the different abilities, interest or learning needs of students and provides different learning approaches based on a student’s learning ability. The model aims to improve students’ academic performance through increasing the lecturer-to-student ratio in the classroom setting. An experimental case study on the model was conducted and the outcome was favourable. Hence, a large-scale implementation was carried out upon the successful trial run. The paper discusses the methodology of the model and its application through the case study and the large-scale implementation.

  18. Wave length dependence of photomorphogenesis in plants

    NARCIS (Netherlands)

    Stolwijk, J.A.J.

    1954-01-01

    Light of various spectral regions (at low or high intensities) supplemented a short day (SD) in white light, or was used alone at high intensity. Two types of relation of wave length to photoperiodic reaction were found: Crucifers were sensitive to blue and infrared (even SD exposure promoted elonga

  19. Hydrodynamic slip length as a surface property

    Science.gov (United States)

    Ramos-Alvarado, Bladimir; Kumar, Satish; Peterson, G. P.

    2016-02-01

    Equilibrium and nonequilibrium molecular dynamics simulations were conducted in order to evaluate the hypothesis that the hydrodynamic slip length is a surface property. The system under investigation was water confined between two graphite layers to form nanochannels of different sizes (3-8 nm). The water-carbon interaction potential was calibrated by matching wettability experiments of graphitic-carbon surfaces free of airborne hydrocarbon contamination. Three equilibrium theories were used to calculate the hydrodynamic slip length. It was found that one of the recently reported equilibrium theories for the calculation of the slip length featured confinement effects, while the others resulted in calculations significantly hindered by the large margin of error observed between independent simulations. The hydrodynamic slip length was found to be channel-size independent using equilibrium calculations, i.e., suggesting a consistency with the definition of a surface property, for 5-nm channels and larger. The analysis of the individual trajectories of liquid particles revealed that the reason for observing confinement effects in 3-nm nanochannels is the high mobility of the bulk particles. Nonequilibrium calculations were not consistently affected by size but by noisiness in the smallest systems.

  20. Wave length dependence of photomorphogenesis in plants

    NARCIS (Netherlands)

    Stolwijk, J.A.J.

    1954-01-01

    Light of various spectral regions (at low or high intensities) supplemented a short day (SD) in white light, or was used alone at high intensity. Two types of relation of wave length to photoperiodic reaction were found: Crucifers were sensitive to blue and infrared (even SD exposure promoted

  1. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Mangino, Massimo

    2015-01-01

    . Based on two independent (discovery and replication) twin studies, comprising 889 twin pairs, we show an increase in the resemblance of leukocyte telomere length between dizygotic twins of older fathers, which is not seen in monozygotic twins. This phenomenon might result from a paternal age...

  2. Tevatron bunch length studies at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Matthew Jones; Bob Kephart; and Rick Vidal

    2002-05-29

    A luminous interaction region can be described by the distribution in (x, y, z) over which p{bar p} interactions are observed in a detector. The spatial size of this distribution can be written in terms of expressions that involve only combinations of the proton and anti-proton bunch sizes. Hence, it is not possible to determine the sizes of the proton and anti-proton bunches independently by fitting the distribution of (x, y, z) from the recorded events. If, in addition to the coordinates (x, y, z) at which p{bar p} interactions occur, the times at which the interactions took place are also measured, then it becomes possible to measure the lengths of the proton and anti-proton bunches separately. This sensitivity is due to a correlation between z and t that arises from the fact that the proton and anti-proton bunches travel in opposite directions. The derivation presented in section 2 quantifies this correlation, resulting in an expression for the probability density as a function of z and t for p{bar p} interactions. By fitting the distributions observed at CDF using this model, we measure the lengths of the proton and anti-proton bunches at times throughout several Tevatron stores. From this analysis the evolution of the bunch lengths can be studied. We attempt to correlate these with other measures of the bunch length obtained using different experimental techniques.

  3. Length, protein–protein interactions, and complexity

    NARCIS (Netherlands)

    Tan, T.; Frenkel, D.; Gupta, V.; Deem, M.W.

    2005-01-01

    The evolutionary reason for the increase in gene length from archaea to prokaryotes to eukaryotes observed in large-scale genome sequencing efforts has been unclear. We propose here that the increasing complexity of protein–protein interactions has driven the selection of longer proteins, as they ar

  4. Age and disease at an arms length

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    a chronic (previously fatal) disease. The active elderly often stick to their image of themselves as active, youthful and energetic in spite of a chronic disease. Old age and disease is not what they identify with and seems to be conceived at an arms length. In the paper the author explores how health...

  5. Bunch length measurements using synchrotron ligth monitor

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion University, Norfolk, VA; Tiefenback, Michael G. [Jefferson Lab, Newport News, VA

    2015-09-01

    The bunch length is measured at CEBAF using an invasive technique. The technique depends on applying an energy chirp for the electron bunch and imaging it through a dispersive region. The measurements are taken through Arc1 and Arc2 at CEBAF. The fundamental equations, procedure and the latest results are given.

  6. Context quantization by minimum adaptive code length

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Wu, Xiaolin

    2007-01-01

    Context quantization is a technique to deal with the issue of context dilution in high-order conditional entropy coding. We investigate the problem of context quantizer design under the criterion of minimum adaptive code length. A property of such context quantizers is derived for binary symbols...

  7. Telomere length in interstitial lung diseases

    NARCIS (Netherlands)

    Snetselaar, Reinier; Van Moorsel, Coline H M; Kazemier, Karin M.; Van Der Vis, Joanne J.; Zanen, Pieter; Van Oosterhout, Matthijs F M; Grutters, Jan C.

    2015-01-01

    Background: Interstitial lung disease (ILD) is a heterogeneous group of rare diseases that primarily affect the pulmonary interstitium. Studies have implicated a role for telomere length (TL) maintenance in ILD, particularly in idiopathic interstitial pneumonia (IIP). Here, we measure TL in a wide

  8. Scattering lengths of calcium and barium isotopes

    NARCIS (Netherlands)

    Dammalapati, U.; Willmann, L.; Knoop, S.

    2011-01-01

    We have calculated the s-wave scattering length of all the even isotopes of calcium (Ca) and barium (Ba) in order to investigate the prospect of Bose-Einstein condensation (BEC). For Ca we have used an accurate molecular potential based on detailed spectroscopic data. Our calculations show that Ca

  9. Optimality Of Variable-Length Codes

    Science.gov (United States)

    Yeh, Pen-Shu; Miller, Warner H.; Rice, Robert F.

    1994-01-01

    Report presents analysis of performances of conceptual Rice universal noiseless coders designed to provide efficient compression of data over wide range of source-data entropies. Includes predictive preprocessor that maps source data into sequence of nonnegative integers and variable-length-coding processor, which adapts to varying entropy of source data by selecting whichever one of number of optional codes yields shortest codeword.

  10. Hydrodynamic slip length as a surface property.

    Science.gov (United States)

    Ramos-Alvarado, Bladimir; Kumar, Satish; Peterson, G P

    2016-02-01

    Equilibrium and nonequilibrium molecular dynamics simulations were conducted in order to evaluate the hypothesis that the hydrodynamic slip length is a surface property. The system under investigation was water confined between two graphite layers to form nanochannels of different sizes (3-8 nm). The water-carbon interaction potential was calibrated by matching wettability experiments of graphitic-carbon surfaces free of airborne hydrocarbon contamination. Three equilibrium theories were used to calculate the hydrodynamic slip length. It was found that one of the recently reported equilibrium theories for the calculation of the slip length featured confinement effects, while the others resulted in calculations significantly hindered by the large margin of error observed between independent simulations. The hydrodynamic slip length was found to be channel-size independent using equilibrium calculations, i.e., suggesting a consistency with the definition of a surface property, for 5-nm channels and larger. The analysis of the individual trajectories of liquid particles revealed that the reason for observing confinement effects in 3-nm nanochannels is the high mobility of the bulk particles. Nonequilibrium calculations were not consistently affected by size but by noisiness in the smallest systems.

  11. The heritability of leucocyte telomere length dynamics

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Möller, Sören;

    2015-01-01

    BACKGROUND: Leucocyte telomere length (LTL) is a complex trait associated with ageing and longevity. LTL dynamics are defined by LTL and its age-dependent attrition. Strong, but indirect evidence suggests that LTL at birth and its attrition during childhood largely explains interindividual LTL...... childhood are crucial for understanding the role of telomere genetics in human ageing and longevity....

  12. Stressful life events and leucocyte telomere length

    DEFF Research Database (Denmark)

    Osler, Merete; Bendix, Laila; Rask, Lene;

    2016-01-01

    Exposure to psychosocial stress is associated with increased risk of a number of somatic and mental disorders with relation to immune system functioning. We aimed to explore whether stressful events in early and recent life was associated with leucocyte telomere length (TL), which is assumed...

  13. Twin correlations of telomere length metrics

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Möller, Sören;

    2015-01-01

    BACKGROUND: Leucocyte telomere length (LTL) is a complex trait associated with ageing and longevity. LTL dynamics are defined by LTL and its age-dependent attrition. Strong, but indirect evidence suggests that LTL at birth and its attrition during childhood largely explains interindividual LTL...... childhood are crucial for understanding the role of telomere genetics in human ageing and longevity....

  14. Phonological length, phonetic duration and aphasia

    NARCIS (Netherlands)

    Gilbers, D.G.; Bastiaanse, Y.R.M.; van der Linde, K.J.

    1997-01-01

    This study discusses an error type that is expected to occur in aphasics suffering from a phonological disorder, i.e. Wernicke's and conduction aphasics, but not in aphasics suffering from a phonetic disorder, i.e. Broca's aphasics. The critical notion is 'phonological length'. It will be argued

  15. Genetically predicted longer telomere length is associated with increased risk of B-cell lymphoma subtypes.

    Science.gov (United States)

    Machiela, Mitchell J; Lan, Qing; Slager, Susan L; Vermeulen, Roel C H; Teras, Lauren R; Camp, Nicola J; Cerhan, James R; Spinelli, John J; Wang, Sophia S; Nieters, Alexandra; Vijai, Joseph; Yeager, Meredith; Wang, Zhaoming; Ghesquières, Hervé; McKay, James; Conde, Lucia; de Bakker, Paul I W; Cox, David G; Burdett, Laurie; Monnereau, Alain; Flowers, Christopher R; De Roos, Anneclaire J; Brooks-Wilson, Angela R; Giles, Graham G; Melbye, Mads; Gu, Jian; Jackson, Rebecca D; Kane, Eleanor; Purdue, Mark P; Vajdic, Claire M; Albanes, Demetrius; Kelly, Rachel S; Zucca, Mariagrazia; Bertrand, Kimberly A; Zeleniuch-Jacquotte, Anne; Lawrence, Charles; Hutchinson, Amy; Zhi, Degui; Habermann, Thomas M; Link, Brian K; Novak, Anne J; Dogan, Ahmet; Asmann, Yan W; Liebow, Mark; Thompson, Carrie A; Ansell, Stephen M; Witzig, Thomas E; Tilly, Hervé; Haioun, Corinne; Molina, Thierry J; Hjalgrim, Henrik; Glimelius, Bengt; Adami, Hans-Olov; Roos, Göran; Bracci, Paige M; Riby, Jacques; Smith, Martyn T; Holly, Elizabeth A; Cozen, Wendy; Hartge, Patricia; Morton, Lindsay M; Severson, Richard K; Tinker, Lesley F; North, Kari E; Becker, Nikolaus; Benavente, Yolanda; Boffetta, Paolo; Brennan, Paul; Foretova, Lenka; Maynadie, Marc; Staines, Anthony; Lightfoot, Tracy; Crouch, Simon; Smith, Alex; Roman, Eve; Diver, W Ryan; Offit, Kenneth; Zelenetz, Andrew; Klein, Robert J; Villano, Danylo J; Zheng, Tongzhang; Zhang, Yawei; Holford, Theodore R; Turner, Jenny; Southey, Melissa C; Clavel, Jacqueline; Virtamo, Jarmo; Weinstein, Stephanie; Riboli, Elio; Vineis, Paolo; Kaaks, Rudolph; Boeing, Heiner; Tjønneland, Anne; Angelucci, Emanuele; Di Lollo, Simonetta; Rais, Marco; De Vivo, Immaculata; Giovannucci, Edward; Kraft, Peter; Huang, Jinyan; Ma, Baoshan; Ye, Yuanqing; Chiu, Brian C H; Liang, Liming; Park, Ju-Hyun; Chung, Charles C; Weisenburger, Dennis D; Fraumeni, Joseph F; Salles, Gilles; Glenn, Martha; Cannon-Albright, Lisa; Curtin, Karen; Wu, Xifeng; Smedby, Karin E; de Sanjose, Silvia; Skibola, Christine F; Berndt, Sonja I; Birmann, Brenda M; Chanock, Stephen J; Rothman, Nathaniel

    2016-04-15

    Evidence from a small number of studies suggests that longer telomere length measured in peripheral leukocytes is associated with an increased risk of non-Hodgkin lymphoma (NHL). However, these studies may be biased by reverse causation, confounded by unmeasured environmental exposures and might miss time points for which prospective telomere measurement would best reveal a relationship between telomere length and NHL risk. We performed an analysis of genetically inferred telomere length and NHL risk in a study of 10 102 NHL cases of the four most common B-cell histologic types and 9562 controls using a genetic risk score (GRS) comprising nine telomere length-associated single-nucleotide polymorphisms. This approach uses existing genotype data and estimates telomere length by weighing the number of telomere length-associated variant alleles an individual carries with the published change in kb of telomere length. The analysis of the telomere length GRS resulted in an association between longer telomere length and increased NHL risk [four B-cell histologic types combined; odds ratio (OR) = 1.49, 95% CI 1.22-1.82,P-value = 8.5 × 10(-5)]. Subtype-specific analyses indicated that chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) was the principal NHL subtype contributing to this association (OR = 2.60, 95% CI 1.93-3.51,P-value = 4.0 × 10(-10)). Significant interactions were observed across strata of sex for CLL/SLL and marginal zone lymphoma subtypes as well as age for the follicular lymphoma subtype. Our results indicate that a genetic background that favors longer telomere length may increase NHL risk, particularly risk of CLL/SLL, and are consistent with earlier studies relating longer telomere length with increased NHL risk.

  16. Surface Enhanced Raman Scattering Based in Situ Hybridization Strategy for Telomere Length Assessment.

    Science.gov (United States)

    Zong, Shenfei; Chen, Chen; Wang, Zhuyuan; Zhang, Yizhi; Cui, Yiping

    2016-02-23

    Assessing telomere length is of vital importance since telomere length is closely related with several fatal diseases such as atherosclerosis and cancer. Here, we present a strategy to assess/measure telomere length, that is, surface enhanced Raman scattering (SERS) based in situ hybridization (SISH). The SISH method uses two kinds of SERS nanoprobes to hybridize in situ with telomeres and centromeres, respectively. The telomere specific SERS nanoprobe is called the Telo-probe, while the centromere specific SERS nanoprobe is called the Centro-probe. They are composed of metal nanoparticles (NPs), Raman reporter molecules and specially designed DNA strands. With longer telomeres, more Telo-probes will hybridize with them, resulting in a stronger SERS signal. To exclude possible influence of the SERS intensity by external factors (such as the nanoprobe concentration, the cell number or different batches of nanoprobes), centromeres are used as the inner control, which can be recognized by Centro-probes. Telomere length is evaluated using a redefined telomere-to-centromere ratio (T/C ratio). The calculation method for T/C ratio in SISH method is more reliable than that in fluorescent in situ hybridization (FISH). In addition, unlike FISH method, the SISH method is insensitive to autofluorescence. Moreover, SISH method can be used to analyze single telomeres. These features make SISH an excellent alternative strategy for telomere length measurement.

  17. 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

  18. On Sources of the Word Length Effect in Young Readers

    Science.gov (United States)

    Gagl, Benjamin; Hawelka, Stefan; Wimmer, Heinz

    2015-01-01

    We investigated how letter length, phoneme length, and consonant clusters contribute to the word length effect in 2nd- and 4th-grade children. They read words from three different conditions: In one condition, letter length increased but phoneme length did not due to multiletter graphemes (H"aus"-B"auch"-S"chach"). In…

  19. Monitoring of electron bunch length by using Terahertz coherent transition radiation

    Science.gov (United States)

    Su, Xiaolu; Yan, Lixin; Du, Yingchao; Zhang, Zhen; Zhou, Zheng; Wang, Dong; Zheng, Lianmin; Tian, Qili; Huang, Wenhui; Tang, Chuanxiang

    2017-07-01

    In this paper, ultrashort bunch length monitoring was demonstrated based on Terahertz (THz) coherent transition radiation (CTR) in Tsinghua Thomson scattering X-ray (TTX) source. The radiation produced by electron bunch is split into three paths: one of them is used to detect the total energy, while the other two paths are filtered with different THz band-pass filters before detection. The bunch length variation can be obtained by calculating the ratio between the filtered energy and the total energy. The bunch is compressed by a chicane and via changing the current of chicane, the ratio of filtered energy and total energy changed correspondingly. It is a simple supplemental approach to monitor the bunch length during beam conditioning and facility operation. Bunch arrival-time jitter and nonlinear effects in chicane are observed in the experiment during the measurement of filtered energy and total energy.

  20. Electrostatic effect of H1-histone protein binding on nucleosome repeat length

    Science.gov (United States)

    Cherstvy, Andrey G.; Teif, Vladimir B.

    2014-08-01

    Within a simple biophysical model we describe the effect of electrostatic binding of H1 histone proteins on the nucleosome repeat length in chromatin. The length of wrapped DNA optimizes its binding energy to the histone core and the elastic energy penalty of DNA wrapping. The magnitude of the effect predicted from our model is in agreement with the systematic experimental data on the linear variation of nucleosome repeat lengths with H1/nucleosome ratio (Woodcock C L et al 2006 Chromos. Res. 14 17-25). We compare our model to the data for different cell types and organisms, with a widely varying ratio of bound H1 histones per nucleosome. We underline the importance of this non-specific histone-DNA charge-balance mechanism in regulating the positioning of nucleosomes and the degree of compaction of chromatin fibers in eukaryotic cells.

  1. Odds ratios deconstructed: A new way to understand and explain odds ratios as conditional risk ratios.

    Science.gov (United States)

    Hoppe, Fred M; Hoppe, Daniel J; Walter, Stephen D

    2017-02-01

    The aim of this analysis was to provide an alternative derivation of the odds ratio (OR) to provide an intuitive meaning, freeing it from any mention of odds, which may make it a more useful concept for clinicians to use when describing treatment effect. By examining the four possible combinations of treatment/control and corresponding outcomes, we considered the conditional risk ratio (RR, also known as relative risk) of an event with the treatment compared with an event with the control for pairs of patients for whom treatment and control would yield different results. Both matched and unmatched studies are considered. We found that the OR could be derived as the RR of an outcome with treatment compared with an outcome with control conditional on the treatment and control resulting in different outcomes, thus providing a measure of the net benefit of treatment. It has been claimed that the OR comparing the effect of treatment vs. control does not have the same clinical interpretability as RR because it involves ratios of odds and so is difficult to explain in terms of patient numbers. This new derivation provides an interpretation of the OR as an RR but conditional on treatment and control resulting in different outcomes. This may help explain the reason ORs cause interpretation difficulties in practice. Moreover, the OR may be a more clinically useful parameter to patients because it deals with only those situations where the outcome differs between the two groups. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Optical frequency standards for time and length applications

    Science.gov (United States)

    Hong, Feng-Lei

    2017-01-01

    The last decade has witnessed tremendous progress in research on optical frequency metrology. Optical frequency standards using optical lattice and single-ion trap technologies have reached levels of stability and accuracy that surpass the performance of the best Cs fountain atomic clocks by orders of magnitude. Optical frequency standards are also used for various applications including length metrology. Optical frequency measurement and links using optical frequency combs and optical fibres play important roles in the development of optical frequency standards. This article introduces optical frequency standards recommended by the International Committee for Weights and Measures (CIPM) along with updates provided by recent research results. Frequency ratio measurements and remote frequency comparisons are addressed in relation to the work whose goal is to redefine the second. Optical frequency standard and optical frequency comb applications are also described.

  3. Gender ratios for reading difficulties

    OpenAIRE

    Hawke, Jesse L.; Olson, Richard K.; Willcutt, Erik G.; Wadsworth, Sally J.; DeFries, John C.

    2009-01-01

    The prevalence of reading difficulties is typically higher in males than females in both referred and research-identified samples, and the ratio of males to females is greater in more affected samples. To explore possible gender differences in reading performance, we analyzed data from 1,133 twin pairs in which at least one member of each pair had a school-history of reading problems and from 684 twin pairs from a comparison sample with no reading difficulties. Although the difference between...

  4. GOLD and the fixed ratio

    Directory of Open Access Journals (Sweden)

    Vestbo J

    2012-09-01

    Full Text Available Jørgen VestboUniversity of Manchester, Manchester, UKI read with interest the paper entitled "Diagnosis of airway obstruction in the elderly: contribution of the SARA study" by Sorino et al in a recent issue of this journal.1 Being involved in the Global Initiative for Obstructive Lung Diseases (GOLD, it is nice to see the interest sparked by the GOLD strategy document. However, in the paper by Sorino et al, there are a few misunderstandings around GOLD and the fixed ratio (forced expiratory volume in 1 second/forced volume vital capacity < 0.70 that need clarification.View original paper by Sorino and colleagues.

  5. Magnetic field modification to the relativistic runaway electron avalanche length

    Science.gov (United States)

    Cramer, E. S.; Dwyer, J. R.; Rassoul, H. K.

    2016-11-01

    This paper explores the impact of the geomagnetic field on the relativistic runaway electron avalanche length, λe-. Coleman and Dwyer (2006) developed an analytical fit to Monte Carlo simulations using the Runaway Electron Avalanche Model. In this work, we repeat this process but with the addition of the geomagnetic field in the range of [100,900]/n μT, where n is the ratio of the density of air at altitude to the sea level density. As the ambient electric field approaches the runaway threshold field (Eth≈284 kV/m sea level equivalent), it is shown that the magnetic field has an impact on the orientation of the resulting electron beam. The runaway electrons initially follow the vertically oriented electric field but then are deflected in the v × B direction, and as such, the electrons experience more dynamic friction due to the increase in path length. This will be shown to result in a difference in the avalanche length from the case where B = 0. It will also be shown that the average energy of the runaway electrons will decrease while the required electric field to produce runaway electrons increases. This study is also important in understanding the physics of terrestrial gamma ray flashes (TGFs). Not only will this work impact relativistic feedback rates determined from simulations, it may also be useful in studying spectroscopy of TGFs observed from balloon and aircraft measurements. These models may also be used in determining beaming properties of TGFs originating in the tropical regions seen from orbiting spacecraft.

  6. Spanish norms for completion of restricted length word stems.

    Science.gov (United States)

    Soler, María José; Dasí, Carmen; Ruiz, Juan Carlos; Cervera, Teresa

    2016-12-06

    This study presents a normative database of Spanish restricted length word stems that provides useful information for the selection of stimuli in memory experiments with Word Stem Completion (WSC) tasks. The database includes indices relative to stems (total baseline completion, priming baseline completion, priming, number of completions, ratio between given and deleted letters, and syllabic structure), and indices relative to characteristics of the words used to obtain the stems (frequency, familiarity, number of meanings, length, number of syllables, arousal, and valence). A WSC task was performed by 515 participants to calculate priming and baseline indices. An Exploratory Factor Analysis showed that these indices are grouped in four factors: perceptual, lexical, emotional, and response competition. Stepwise regression analyses performed with these factors showed that the lexical, response competition, and perceptual factors predict priming baseline completion, while only the lexical factor predicts priming. The model that best explains the relationship between priming and priming baseline completion was a cubic model, and the optimum baseline values for achieving priming were between .31 and .36. These norms can be downloaded as Supplemental Materials for this article from https://nuvol.uv.es/owncloud/index.php/s/hpj9by1qbENdjfj .

  7. Similarity theory based on the Dougherty-Ozmidov length scale

    CERN Document Server

    Grachev, Andrey A; Fairall, Christopher W; Guest, Peter S; Persson, P Ola G

    2014-01-01

    Local similarity theory is suggested based on the Brunt-Vaisala frequency and the dissipation rate of turbulent kinetic energy instead the turbulent fluxes used in the traditional Monin-Obukhov similarity theory. Based on dimensional analysis (Pi theorem), it is shown that any properly scaled statistics of the small-scale turbulence are universal functions of a stability parameter defined as the ratio of a reference height z and the Dougherty-Ozmidov length scale which in the limit of z-less stratification is linearly proportional to the Obukhov length scale. Measurements of atmospheric turbulence made at five levels on a 20-m tower over the Arctic pack ice during the Surface Heat Budget of the Arctic Ocean experiment (SHEBA) are used to examine the behaviour of different similarity functions in the stable boundary layer. It is found that in the framework of this approach the non-dimensional turbulent viscosity is equal to the gradient Richardson number whereas the non-dimensional turbulent thermal diffusivit...

  8. Persistence Length of DNA Macromolecule with Kinks

    CERN Document Server

    Simonov, Kyrylo

    2014-01-01

    The study of configurational parameters of deformed DNA is a relevant problem in research of such important biological process as double helix compactization in cell. The deformations accompanied with local disruptions of the regular macromolecule structure cause significant bending of the double helix, or kinks. In this paper an approach for Kratky-Porod model to calculate persistence length of DNA macromolecule with kinks is developed. The presented approach considers kinks of arbitrary configuration, including two basic types of kinks, type 1 - sharp kink caused by unstacking a single base pair step, and type 2 - intrinsic-induced kink that involves several base pairs. Within developed approach analytical expressions for persistence length, coil size and gyration radius of kinky double helix were obtained.

  9. The Effective Key Length of Watermarking Schemes

    CERN Document Server

    Bas, Patrick

    2012-01-01

    Whereas the embedding distortion, the payload and the robustness of digital watermarking schemes are well understood, the notion of security is still not completely well defined. The approach proposed in the last five years is too theoretical and solely considers the embedding process, which is half of the watermarking scheme. This paper proposes a new measurement of watermarking security, called the effective key length, which captures the difficulty for the adversary to get access to the watermarking channel. This new methodology is applied to additive spread spectrum schemes where theoretical and practical computations of the effective key length are proposed. It shows that these schemes are not secure as soon as the adversary gets observations in the Known Message Attack context.

  10. Length-scale dependent phonon interactions

    CERN Document Server

    Srivastava, Gyaneshwar

    2014-01-01

    This book presents  a comprehensive description of phonons and their interactions in systems with different dimensions and length scales. Internationally-recognized leaders describe theories and measurements of phonon interactions  in relation to the design of materials with exotic properties such as metamaterials, nano-mechanical systems, next-generation electronic, photonic, and acoustic devices, energy harvesting, optical information storage, and applications of phonon lasers in a variety of fields. The emergence of techniques for control of semiconductor properties and geometry has enabled engineers to design structures in which functionality is derived from controlling electron behavior. As manufacturing techniques have greatly expanded the list of available materials and the range of attainable length scales, similar opportunities now exist for designing devices whose functionality is derived from controlling phonon behavior. However, progress in this area is hampered by gaps in our knowledge of phono...

  11. Distance and Cable Length Measurement System

    Directory of Open Access Journals (Sweden)

    Jonay Toledo

    2009-12-01

    Full Text Available A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement.

  12. Analytical calculation of chain length in ferrofluids

    Indian Academy of Sciences (India)

    M Devi; P P Dutta; D Mohanta

    2015-02-01

    The response of a typical ferrofluid (FF) lies in its explicit property of chain formation of magnetic nanoparticles. The most significant magneto-optic (MO) and magneto-viscous (MV) effects of FF are attributed to chaining effect. In the present research, an effort was made to analytically justify the dependence of the structure evolution of FFs on different measurable parameters involved in MO and MV effects. The problem is treated with the help of dimensional analysis and an empirical relation is formulated relating the equilibrium chain length with Verdet coefficient (constant), particle diameter, viscosity of the carrier fluid, particle density, magnetization and shear rate. The formulated relation of chain length is supported by error analysis to yield the uncertainty in the result. The maximum uncertainty in four sets of data is found as ∼0.75.

  13. Distance and Cable Length Measurement System

    Science.gov (United States)

    Hernández, Sergio Elias; Acosta, Leopoldo; Toledo, Jonay

    2009-01-01

    A simple, economic and successful design for distance and cable length detection is presented. The measurement system is based on the continuous repetition of a pulse that endlessly travels along the distance to be detected. There is a pulse repeater at both ends of the distance or cable to be measured. The endless repetition of the pulse generates a frequency that varies almost inversely with the distance to be measured. The resolution and distance or cable length range could be adjusted by varying the repetition time delay introduced at both ends and the measurement time. With this design a distance can be measured with centimeter resolution using electronic system with microsecond resolution, simplifying classical time of flight designs which require electronics with picosecond resolution. This design was also applied to position measurement. PMID:22303169

  14. Aligning Sequences by Minimum Description Length

    Directory of Open Access Journals (Sweden)

    John S. Conery

    2008-01-01

    Full Text Available This paper presents a new information theoretic framework for aligning sequences in bioinformatics. A transmitter compresses a set of sequences by constructing a regular expression that describes the regions of similarity in the sequences. To retrieve the original set of sequences, a receiver generates all strings that match the expression. An alignment algorithm uses minimum description length to encode and explore alternative expressions; the expression with the shortest encoding provides the best overall alignment. When two substrings contain letters that are similar according to a substitution matrix, a code length function based on conditional probabilities defined by the matrix will encode the substrings with fewer bits. In one experiment, alignments produced with this new method were found to be comparable to alignments from CLUSTALW. A second experiment measured the accuracy of the new method on pairwise alignments of sequences from the BAliBASE alignment benchmark.

  15. Effects of subcutaneous IL-2 therapy on telomere lengths in PBMC in HIV-infected patients

    DEFF Research Database (Denmark)

    Aladdin, H; Larsen, C S; Schjerling, P

    2001-01-01

    times a week for 24 weeks. Mean TRF length was decreased on average by 267 bp at week 4 (P = 0.03) and 286 bp at week 8 (P = 0.09). Individual TRF changes at weeks 12, 16, 20 and 24 were highly variable. However, in the 12 weeks following therapy, TRF lengths generally increased reaching baseline levels...... by the end of the study. At baseline, mean TRF lengths were positively correlated to the ratio of naïve and memory phenotype within both CD4+ and CD8+ cells. This study shows that IL-2 treatment induces transient shortened mean TRF lengths in PBMC from HIV-infected individuals, indicating that IL-2 enhances...

  16. Optical path length and trajectory stability in rotationally asymmetric multipass cells.

    Science.gov (United States)

    Harden, Galen H; Cortes-Herrera, Luis E; Hoffman, Anthony J

    2016-08-22

    We describe the behavior of optical trajectories in multipass rotationally asymmetric cavities (RACs) using a phase-space motivated approach. Emphasis is placed on generating long optical paths. A trajectory with an optical path length of 18 m is generated within a 68 cm3 volume. This path length to volume ratio (26.6 cm-2) is large compared to current state of the art multipass cells such as the cylindrical multipass cell (6.6 cm-2) and astigmatic Herriott cell (9 cm-2). Additionally, the effect of small changes to the input conditions on the path length is studied and compared to the astigmatic Herriott cell. This work simplifies the process of designing RACs with long optical path lengths and could lead to broader implementation of these multipass cells.

  17. Investigation of diffusion length distribution on polycrystalline silicon wafers via photoluminescence methods

    Science.gov (United States)

    Lou, Shishu; Zhu, Huishi; Hu, Shaoxu; Zhao, Chunhua; Han, Peide

    2015-01-01

    Characterization of the diffusion length of solar cells in space has been widely studied using various methods, but few studies have focused on a fast, simple way to obtain the quantified diffusion length distribution on a silicon wafer. In this work, we present two different facile methods of doing this by fitting photoluminescence images taken in two different wavelength ranges or from different sides. These methods, which are based on measuring the ratio of two photoluminescence images, yield absolute values of the diffusion length and are less sensitive to the inhomogeneity of the incident laser beam. A theoretical simulation and experimental demonstration of this method are presented. The diffusion length distributions on a polycrystalline silicon wafer obtained by the two methods show good agreement. PMID:26364565

  18. Offset Optimization Based on Queue Length Constraint for Saturated Arterial Intersections

    Directory of Open Access Journals (Sweden)

    Xianmin Song

    2012-01-01

    Full Text Available Offset optimization is of critical importance to the traffic control system, especially when spillovers appear. In order to avoid vehicle queue spillovers, an arterial offset optimization model was presented in saturated arterial intersections based on minimizing the queue length over the whole duration of the saturated traffic environment. The paper uses the shockwave theory to analyze the queue evolution process of the intersection approach under the saturated traffic environment. Then through establishing and analyzing a function relationship between offset and the maximum queue length per cycle, a mapping model of offset and maximum queue length was established in the saturated condition. The validity and sensitivity of this model were tested by the VISSIM simulation environment. Finally, results showed that when volumes ratios are 0.525–0.6, adjusting offset reasonably under the saturated condition could decrease the queue length and effectively improve the vehicle operating efficiency.

  19. Short Telomere Length, Myocardial Infarction, Ischemic Heart Disease, and Early Death

    DEFF Research Database (Denmark)

    Weischer, Maren; Bojesen, Stig E; Cawthon, Richard M;

    2012-01-01

    OBJECTIVE: We tested the hypothesis that short telomere length is associated with increased risk of myocardial infarction, ischemic heart disease, and early death. METHODS AND RESULTS: We measured leukocyte telomere length in 2 prospective studies of 19 838 Danish general population participants...... from the Copenhagen City Heart Study and the Copenhagen General Population Study. Participants were followed for up to 19 years for incident myocardial infarction (n=929), ischemic heart disease (n=2038), and death (n=4342). Follow-up was 100% complete. Telomere length decreased linearly...... with increasing age in women and men in both studies (P=7×10(-74) to P=3×10(-125)). Multifactorially adjusted hazard ratios were 1.10 (95% CI 1.01-1.19) for myocardial infarction, 1.06 (1.00-1.11) for ischemic heart disease, and 1.09 (1.05-1.13) for early death per 1000-base pair decrease in telomere length...

  20. Determination of gas length for gas-assisted extrusion forming of polymer melt

    Science.gov (United States)

    Ren, Z.; Huang, X. Y.

    2017-02-01

    To determine the optimal gas length for the gas-assisted etrusion forming of melt, numerical investigations about the gas length on the extrudate swell of melt were performed by using the finite element method. Meanwhile, the geometric model of gas-assistd extrusion forming was established. The full slip boundary condition was used as the gas-assisted condition. Numerical results show that the gas length should be shortened with increasing of the inlet volumme flow rate of melt. In addition, under the given inlet volume flow rate of melt, the extrudate swell ratio, X velocity and shear stress of melt greatly decreases with increasing the gas length. Accroding to the numerical results and experiences reported past time, under the inlet volume flow rate of 0.5cm3/s, the optimal gas lenth of gas-assisted extrusion forming is about 10mm.

  1. New hydrocracking catalysts increase throughput, run length

    Energy Technology Data Exchange (ETDEWEB)

    Huizinga, T. [Shell Internationale Petroleum Mij., The Hague (Netherlands); Theunissen, J.M.H. [Rayong Refinery Co. Ltd., Rayong (Thailand); Minderhoud, H.; Veen, R. van [Koninklijke/Shell-Lab., Amsterdam (Netherlands)

    1995-06-26

    An improved, second-stage hydrocracking catalyst has been developed by combining stabilized Y zeolites with amorphous silica alumina cracking components. A commercial application of this catalyst, along with a new, first-stage zeolitic hydrocracking catalyst, resulted in increased unit throughput and cycle length. The paper discusses the hydrocracking process, first-stage catalysts, second-stage catalysts, hydrogenation process, commercial results, and product properties.

  2. Minimum Description Length Shape and Appearance Models

    DEFF Research Database (Denmark)

    Thodberg, Hans Henrik

    2003-01-01

    The Minimum Description Length (MDL) approach to shape modelling is reviewed. It solves the point correspondence problem of selecting points on shapes defined as curves so that the points correspond across a data set. An efficient numerical implementation is presented and made available as open s...... source Matlab code. The problems with the early MDL approaches are discussed. Finally the MDL approach is extended to an MDL Appearance Model, which is proposed as a means to perform unsupervised image segmentation....

  3. Short Rayleigh length free electron lasers

    Directory of Open Access Journals (Sweden)

    W. B. Colson

    2006-03-01

    Full Text Available Conventional free electron laser (FEL oscillators minimize the optical mode volume around the electron beam in the undulator by making the resonator Rayleigh length about one third to one half of the undulator length. This maximizes gain and beam-mode coupling. In compact configurations of high-power infrared FELs or moderate power UV FELs, the resulting optical intensity can damage the resonator mirrors. To increase the spot size and thereby reduce the optical intensity at the mirrors below the damage threshold, a shorter Rayleigh length can be used, but the FEL interaction is significantly altered. We model this interaction using a coordinate system that expands with the rapidly diffracting optical mode from the ends of the undulator to the mirrors. Simulations show that the interaction of the strongly focused optical mode with a narrow electron beam inside the undulator distorts the optical wave front so it is no longer in the fundamental Gaussian mode. The simulations are used to study how mode distortion affects the single-pass gain in weak fields, and the steady-state extraction in strong fields.

  4. Radiation length imaging with high resolution telescopes

    CERN Document Server

    Stolzenberg, U; Schwenker, B; Wieduwilt, P; Marinas, C; Lütticke, F

    2016-01-01

    The construction of low mass vertex detectors with a high level of system integration is of great interest for next generation collider experiments. Radiation length images with a sufficient spatial resolution can be used to measure and disentangle complex radiation length $X$/$X_0$ profiles and contribute to the understanding of vertex detector systems. Test beam experiments with multi GeV particle beams and high-resolution tracking telescopes provide an opportunity to obtain precise 2D images of the radiation length of thin planar objects. At the heart of the $X$/$X_0$ imaging is a spatially resolved measurement of the scattering angles of particles traversing the object under study. The main challenges are the alignment of the reference telescope and the calibration of its angular resolution. In order to demonstrate the capabilities of $X$/$X_0$ imaging, a test beam experiment has been conducted. The devices under test were two mechanical prototype modules of the Belle II vertex detector. A data sample of ...

  5. Step length estimation using handheld inertial sensors.

    Science.gov (United States)

    Renaudin, Valérie; Susi, Melania; Lachapelle, Gérard

    2012-01-01

    In this paper a novel step length model using a handheld Micro Electrical Mechanical System (MEMS) is presented. It combines the user's step frequency and height with a set of three parameters for estimating step length. The model has been developed and trained using 12 different subjects: six men and six women. For reliable estimation of the step frequency with a handheld device, the frequency content of the handheld sensor's signal is extracted by applying the Short Time Fourier Transform (STFT) independently from the step detection process. The relationship between step and hand frequencies is analyzed for different hand's motions and sensor carrying modes. For this purpose, the frequency content of synchronized signals collected with two sensors placed in the hand and on the foot of a pedestrian has been extracted. Performance of the proposed step length model is assessed with several field tests involving 10 test subjects different from the above 12. The percentages of error over the travelled distance using universal parameters and a set of parameters calibrated for each subject are compared. The fitted solutions show an error between 2.5 and 5% of the travelled distance, which is comparable with that achieved by models proposed in the literature for body fixed sensors only.

  6. Measuring scattering lengths of gaseous samples

    Science.gov (United States)

    Huber, M. G.; Black, T. C.; Haun, R.; Pushin, D. A.; Shahi, C. B.; Weitfeldt, F. E.

    2016-03-01

    Neutron interferometry represents one of the most precise techniques for measuring the coherent scattering lengths (bc) of particular nuclear isotopes. Currently bc for helium-4 is known only to 1% relative uncertainty; a factor of ten higher than precision measurements of other light isotopes. Scattering lengths are measured using a neutron interferometer and by comparing the phase shift a neutron acquires as it passes through a gaseous sample relative to that of a neutron passing through vacuum. The density of the gas is determined by continuous monitoring of the sample's temperature and pressure. Challenges for these types of experiments include achieving the necessary long-term phase stability and accurate determination of the phase shift caused by the aluminum cell used to hold the gas; a phase shift many times greater than that of the sample. The present status on the effort to measure the n-4He scattering length at the NIST center for Neutron Research will be given. Financial support provided by the NSERC `Create' and `Discovery' programs, CERC, NIST and NSF Grant PHY-1205342.

  7. Step Length Estimation Using Handheld Inertial Sensors

    Directory of Open Access Journals (Sweden)

    Gérard Lachapelle

    2012-06-01

    Full Text Available In this paper a novel step length model using a handheld Micro Electrical Mechanical System (MEMS is presented. It combines the user’s step frequency and height with a set of three parameters for estimating step length. The model has been developed and trained using 12 different subjects: six men and six women. For reliable estimation of the step frequency with a handheld device, the frequency content of the handheld sensor’s signal is extracted by applying the Short Time Fourier Transform (STFT independently from the step detection process. The relationship between step and hand frequencies is analyzed for different hand’s motions and sensor carrying modes. For this purpose, the frequency content of synchronized signals collected with two sensors placed in the hand and on the foot of a pedestrian has been extracted. Performance of the proposed step length model is assessed with several field tests involving 10 test subjects different from the above 12. The percentages of error over the travelled distance using universal parameters and a set of parameters calibrated for each subject are compared. The fitted solutions show an error between 2.5 and 5% of the travelled distance, which is comparable with that achieved by models proposed in the literature for body fixed sensors only.

  8. Genetic Variants Related to Longer Telomere Length are Associated with Increased Risk of Renal Cell Carcinoma.

    Science.gov (United States)

    Machiela, Mitchell J; Hofmann, Jonathan N; Carreras-Torres, Robert; Brown, Kevin M; Johansson, Mattias; Wang, Zhaoming; Foll, Matthieu; Li, Peng; Rothman, Nathaniel; Savage, Sharon A; Gaborieau, Valerie; McKay, James D; Ye, Yuanqing; Henrion, Marc; Bruinsma, Fiona; Jordan, Susan; Severi, Gianluca; Hveem, Kristian; Vatten, Lars J; Fletcher, Tony; Koppova, Kvetoslava; Larsson, Susanna C; Wolk, Alicja; Banks, Rosamonde E; Selby, Peter J; Easton, Douglas F; Pharoah, Paul; Andreotti, Gabriella; Freeman, Laura E Beane; Koutros, Stella; Albanes, Demetrius; Mannisto, Satu; Weinstein, Stephanie; Clark, Peter E; Edwards, Todd E; Lipworth, Loren; Gapstur, Susan M; Stevens, Victoria L; Carol, Hallie; Freedman, Matthew L; Pomerantz, Mark M; Cho, Eunyoung; Kraft, Peter; Preston, Mark A; Wilson, Kathryn M; Gaziano, J Michael; Sesso, Howard S; Black, Amanda; Freedman, Neal D; Huang, Wen-Yi; Anema, John G; Kahnoski, Richard J; Lane, Brian R; Noyes, Sabrina L; Petillo, David; Colli, Leandro M; Sampson, Joshua N; Besse, Celine; Blanche, Helene; Boland, Anne; Burdette, Laurie; Prokhortchouk, Egor; Skryabin, Konstantin G; Yeager, Meredith; Mijuskovic, Mirjana; Ognjanovic, Miodrag; Foretova, Lenka; Holcatova, Ivana; Janout, Vladimir; Mates, Dana; Mukeriya, Anush; Rascu, Stefan; Zaridze, David; Bencko, Vladimir; Cybulski, Cezary; Fabianova, Eleonora; Jinga, Viorel; Lissowska, Jolanta; Lubinski, Jan; Navratilova, Marie; Rudnai, Peter; Szeszenia-Dabrowska, Neonila; Benhamou, Simone; Cancel-Tassin, Geraldine; Cussenot, Olivier; Bueno-de-Mesquita, H Bas; Canzian, Federico; Duell, Eric J; Ljungberg, Börje; Sitaram, Raviprakash T; Peters, Ulrike; White, Emily; Anderson, Garnet L; Johnson, Lisa; Luo, Juhua; Buring, Julie; Lee, I-Min; Chow, Wong-Ho; Moore, Lee E; Wood, Christopher; Eisen, Timothy; Larkin, James; Choueiri, Toni K; Lathrop, G Mark; Teh, Bin Tean; Deleuze, Jean-Francois; Wu, Xifeng; Houlston, Richard S; Brennan, Paul; Chanock, Stephen J; Scelo, Ghislaine; Purdue, Mark P

    2017-08-07

    Relative telomere length in peripheral blood leukocytes has been evaluated as a potential biomarker for renal cell carcinoma (RCC) risk in several studies, with conflicting findings. We performed an analysis of genetic variants associated with leukocyte telomere length to assess the relationship between telomere length and RCC risk using Mendelian randomization, an approach unaffected by biases from temporal variability and reverse causation that might have affected earlier investigations. Genotypes from nine telomere length-associated variants for 10 784 cases and 20 406 cancer-free controls from six genome-wide association studies (GWAS) of RCC were aggregated into a weighted genetic risk score (GRS) predictive of leukocyte telomere length. Odds ratios (ORs) relating the GRS and RCC risk were computed in individual GWAS datasets and combined by meta-analysis. Longer genetically inferred telomere length was associated with an increased risk of RCC (OR=2.07 per predicted kilobase increase, 95% confidence interval [CI]:=1.70-2.53, p0.5) with GWAS-identified RCC risk variants (rs10936599 and rs9420907) from the telomere length GRS; despite this exclusion, a statistically significant association between the GRS and RCC risk persisted (OR=1.73, 95% CI=1.36-2.21, pbody of evidence indicating some aspect of longer telomere length is important for RCC risk. Telomeres are segments of DNA at chromosome ends that maintain chromosomal stability. Our study investigated the relationship between genetic variants associated with telomere length and renal cell carcinoma risk. We found evidence suggesting individuals with inherited predisposition to longer telomere length are at increased risk of developing renal cell carcinoma. Published by Elsevier B.V.

  9. Energetics of the Frank-Starling effect in rabbit myocardium: economy and efficiency depend on muscle length.

    Science.gov (United States)

    Holmes, Jeffrey W; Hünlich, Mark; Hasenfuss, Gerd

    2002-07-01

    We tested the hypothesis that economy and efficiency are independent of length in intact cardiac muscle over its normal working range. We measured force, force-time integral, force-length area, and myocardial oxygen consumption in eight isometrically contracting rabbit right ventricular papillary muscles. 2,3-Butanedione monoxime was used to partition nonbasal oxygen consumption into tension-independent and tension-dependent components. Developed force, force-time integral, and force-length area increased by factors of 2.4, 2.7, and 4.8, respectively, as muscle length was increased from 90% to 100% maximal length, whereas tension-dependent oxygen consumption increased only 1.6-fold. Economy (the ratio of force-time integral to tension-dependent oxygen consumption) increased significantly with muscle length, as did contractile efficiency, the ratio of force-length area to tension-dependent oxygen consumption. The average force-length area-nonbasal oxygen consumption intercept was more than the twice tension-independent oxygen consumption. We conclude that economy and efficiency increase with length in rabbit myocardium. This conclusion is consistent with published data in isolated rabbit and dog hearts but at odds with studies in skinned myocardium.

  10. Human lung volume, alveolar surface area, and capillary length

    DEFF Research Database (Denmark)

    Wiebe, B. M.; Laursen, Henning

    1995-01-01

    Cavalieri's principle, length density, morphometry, stereology, surface density, vertical sections, vertical slices......Cavalieri's principle, length density, morphometry, stereology, surface density, vertical sections, vertical slices...

  11. Clinicopathological characteristics of TERT promoter mutation and telomere length in hepatocellular carcinoma

    Science.gov (United States)

    Lee, Hye Won; Park, Tae In; Jang, Se Young; Park, Soo Young; Park, Won-Jin; Jung, Soo-Jung; Lee, Jae-Ho

    2017-01-01

    Abstract Promoter mutations in telomerase reverse transcriptase (TERT) and telomere length have been studied in various tumors. In the present study, the frequency and clinical characteristics of TERT promoter mutation and telomere length were studied in hepatocellular carcinoma (HCC). TERT promoter mutation and telomere length were analyzed in 162 tumor samples of the patients with HCC by sequencing and real-time PCR, respectively. The TERT promoter mutation rate was 28.8% (46/160) in HCC and was associated with males (P = 0.027). The telomere length was not significantly different in the presence of a TERT promoter mutation but was shorter in high-grade tumor stages (P = 0.048). Survival analyses showed that poor overall survival was associated with longer telomere length (P = 0.013). However, the TERT promoter mutation did not have a prognostic value for HCC. Multivariate survival analyses demonstrated that the telomere length was an independent prognostic marker for poor overall survival (hazard ratio = 1.75, 95% confidence interval: 1.046–2.913, P = 0.033). These data demonstrated that TERT promoter mutation is a frequent event in HCC; however, telomere length, but not the presence of a TERT promoter mutation, might have potential value as a prognostic indicator of HCC. PMID:28151853

  12. Optimization of element length for imaging small volumetric reflectors with linear ultrasonic arrays

    Science.gov (United States)

    Barber, T. S.; Wilcox, P. D.; Nixon, A. D.

    2016-02-01

    A 3D ultrasonic simulation study is presented, aimed at understanding the effect of element length for imaging small volumetric flaws with linear arrays in ultrasonically noisy materials. The geometry of a linear array can be described by the width, pitch and total number of the elements along with the length perpendicular to imaging plane. This paper is concerned with the latter parameter, which tends to be ignored in array optimization studies and is often chosen arbitrarily for industrial array inspections. A 3D analytical model based on imaging a point target is described, validated and used to make calculations of relative Signal-to-Noise Ratio (SNR) as a function of element length. SNR is found to be highly sensitive to element length with a 12dB variation observed over the length range investigated. It is then demonstrated that the optimal length can be predicted directly from the Point Spread Function (PSF) of the imaging system as well as the natural focal point of the array element from 2D beam profiles perpendicular to the imaging plane. This result suggests that the optimal length for any imaging position can be predicted without the need for a full 3D model and is independent of element pitch and the number of elements. Array element design guidelines are then described with respect to wavelength and extensions of these results are discussed for application to realistically-sized defects and coarse-grained materials.

  13. Tumour length is an independent prognostic factor of esophageal squamous cell carcinomas

    Institute of Scientific and Technical Information of China (English)

    WU Ning; PANG Lie-wen; CHEN Zhi-ming; MA Qin-yun; CHEN Gang

    2012-01-01

    Background The latest version of the American Joint Committee on Cancer (AJCC) TNM staging system has not comprehensively evaluated the impact of tumour length on survival in patients with esophageal squamous cell carcinoma.Our study explored the relationship between tumour length and clinicopathological characteristics as well as long-term survival.Methods All 202 cases of esophageal resections done from January 1,2004 to December 31,2008 in Huashan Hospital,Fudan University were reviewed and followed up.Results Patients with tumour length >3 cm were related to more advanced tumour stage (X2=55.9,P <0.001),more metastatic lymph nodes (X2=14.6,P <0.001),increased metastatic lymph node ratio (x2=16.1,P <0.001) and worse overall TNM stage (X2=48.1,P <0.001).Univariate and multivariate analyses indicated that tumour length was a significant prognostic risk factor (95% CI 0.235-0.947,P=0.035).Subgroup analyses disclosed that tumour length was a valuable prognostic predictor in patients with lower T stage,absence of metastatic lymph nodes and lower TNM stage.Conclusions Esophageal tumour length is a predictive factor for long-term survival especially for lower tumour stage,absence of metastatic lymph nodes and lower TNM stage patients.Tumour length should be incorporated in the staging system as an important grouping factor for better prognostic evaluation.

  14. Clinicopathological characteristics of TERT promoter mutation and telomere length in hepatocellular carcinoma.

    Science.gov (United States)

    Lee, Hye Won; Park, Tae In; Jang, Se Young; Park, Soo Young; Park, Won-Jin; Jung, Soo-Jung; Lee, Jae-Ho

    2017-02-01

    Promoter mutations in telomerase reverse transcriptase (TERT) and telomere length have been studied in various tumors. In the present study, the frequency and clinical characteristics of TERT promoter mutation and telomere length were studied in hepatocellular carcinoma (HCC). TERT promoter mutation and telomere length were analyzed in 162 tumor samples of the patients with HCC by sequencing and real-time PCR, respectively. The TERT promoter mutation rate was 28.8% (46/160) in HCC and was associated with males (P = 0.027). The telomere length was not significantly different in the presence of a TERT promoter mutation but was shorter in high-grade tumor stages (P = 0.048). Survival analyses showed that poor overall survival was associated with longer telomere length (P = 0.013). However, the TERT promoter mutation did not have a prognostic value for HCC. Multivariate survival analyses demonstrated that the telomere length was an independent prognostic marker for poor overall survival (hazard ratio = 1.75, 95% confidence interval: 1.046-2.913, P = 0.033). These data demonstrated that TERT promoter mutation is a frequent event in HCC; however, telomere length, but not the presence of a TERT promoter mutation, might have potential value as a prognostic indicator of HCC.

  15. High Aspect Ratio Semiconductor Heterojunction Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Redwing, Joan [Pennsylvania State Univ., University Park, PA (United States). Dept. of Material Science and Engineering; Mallouk, Tom [Pennsylvania State Univ., University Park, PA (United States). Dept. of Chemistry; Mayer, Theresa [Pennsylvania State Univ., University Park, PA (United States). Dept. of Electrical Engineering; Dickey, Elizabeth [Pennsylvania State Univ., University Park, PA (United States). Dept. of Materials Science and Engineering; Wronski, Chris [Pennsylvania State Univ., University Park, PA (United States). Dept. of Electrical Engineering

    2013-05-17

    The project focused on the development of high aspect ratio silicon heterojunction (HARSH) solar cells. The solar cells developed in this study consisted of high density vertical arrays of radial junction silicon microwires/pillars formed on Si substrates. Prior studies have demonstrated that vertical Si wire/pillar arrays enable reduced reflectivity and improved light trapping characteristics compared to planar solar cells. In addition, the radial junction structure offers the possibility of increased carrier collection in solar cells fabricated using material with short carrier diffusion lengths. However, the high junction and surface area of radial junction Si wire/pillar array devices can be problematic and lead to increased diode leakage and enhanced surface recombination. This study investigated the use of amorphous hydrogenated Si in the form of a heterojunction-intrinsic-thin layer (HIT) structure as a junction formation method for these devices. The HIT layer structure has widely been employed to reduce surface recombination in planar crystalline Si solar cells. Consequently, it was anticipated that it would also provide significant benefits to the performance of radial junction Si wire/pillar array devices. The overall goals of the project were to demonstrate a HARSH cell with a HIT-type structure in the radial junction Si wire/pillar array configuration and to develop potentially low cost pathways to fabricate these devices. Our studies demonstrated that the HIT structure lead to significant improvements in the open circuit voltage (Voc>0.5) of radial junction Si pillar array devices compared to devices fabricated using junctions formed by thermal diffusion or low pressure chemical vapor deposition (LPCVD). In addition, our work experimentally demonstrated that the radial junction structure lead to improvements in efficiency compared to comparable planar devices for devices fabricated using heavily doped Si that had reduced carrier diffusion

  16. Conscientiousness as a Mediator of the Association between Masculinized Finger-Length Ratios and Attention-Deficit Hyperactivity Disorder (ADHD)

    Science.gov (United States)

    Martel, Michelle M.

    2009-01-01

    Background: One often-overlooked biological risk factor that may help explain sex-biased prevalence rates in psychopathology is sex hormones. Personality traits, which also show sex differences, may mediate relations between biological risk factors like hormones and childhood psychopathology such as ADHD (or, alternatively, be independent risk…

  17. Weather-Corrected Performance Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Dierauf, T.; Growitz, A.; Kurtz, S.; Cruz, J. L. B.; Riley, E.; Hansen, C.

    2013-04-01

    Photovoltaic (PV) system performance depends on both the quality of the system and the weather. One simple way to communicate the system performance is to use the performance ratio (PR): the ratio of the electricity generated to the electricity that would have been generated if the plant consistently converted sunlight to electricity at the level expected from the DC nameplate rating. The annual system yield for flat-plate PV systems is estimated by the product of the annual insolation in the plane of the array, the nameplate rating of the system, and the PR, which provides an attractive way to estimate expected annual system yield. Unfortunately, the PR is, again, a function of both the PV system efficiency and the weather. If the PR is measured during the winter or during the summer, substantially different values may be obtained, making this metric insufficient to use as the basis for a performance guarantee when precise confidence intervals are required. This technical report defines a way to modify the PR calculation to neutralize biases that may be introduced by variations in the weather, while still reporting a PR that reflects the annual PR at that site given the project design and the project weather file. This resulting weather-corrected PR gives more consistent results throughout the year, enabling its use as a metric for performance guarantees while still retaining the familiarity this metric brings to the industry and the value of its use in predicting actual annual system yield. A testing protocol is also presented to illustrate the use of this new metric with the intent of providing a reference starting point for contractual content.

  18. Correlated evolution of sternal keel length and ilium length in birds

    Directory of Open Access Journals (Sweden)

    Tao Zhao

    2017-07-01

    Full Text Available The interplay between the pectoral module (the pectoral girdle and limbs and the pelvic module (the pelvic girdle and limbs plays a key role in shaping avian evolution, but prior empirical studies on trait covariation between the two modules are limited. Here we empirically test whether (size-corrected sternal keel length and ilium length are correlated during avian evolution using phylogenetic comparative methods. Our analyses on extant birds and Mesozoic birds both recover a significantly positive correlation. The results provide new evidence regarding the integration between the pelvic and pectoral modules. The correlated evolution of sternal keel length and ilium length may serve as a mechanism to cope with the effect on performance caused by a tradeoff in muscle mass between the pectoral and pelvic modules, via changing moment arms of muscles that function in flight and in terrestrial locomotion.

  19. Length-Dependent Electromigration Behavior of Sn58Bi Solder and Critical Length of Electromigration

    Science.gov (United States)

    Zhao, Xu; Muraoka, Mikio; Saka, Masumi

    2017-02-01

    On the basis of a developed test structure, electromigration (EM) tests of Sn58Bi solder strips with lengths of 50 μm, 100 μm, and 150 μm were simultaneously conducted at a current density of 27 kA/cm2 at 373 K. Length-dependent EM behavior was detected, and the mechanism is discussed. Bi atoms were segregated to the anode side more easily as the strip length increased, which resulted in the formation of a thicker Bi-rich layer or Sn-Bi mixed hillocks. The results reveal the existence of back flow that depends on the solder joint length. The back flow is most likely caused by an oxide layer formed on the Sn58Bi solder. By measuring the thicknesses of the Bi-rich layers, the Bi drift velocities were obtained. The critical length of the solder joint and the critical product of the length and the current density were estimated to be 16 μm and 43 A/cm, respectively. This observation will assist design of advanced electronic devices to anticipate EM reliability.

  20. Hyperuniformity disorder length spectroscopy for extended particles

    Science.gov (United States)

    Durian, D. J.

    2017-09-01

    The concept of a hyperuniformity disorder length h was recently introduced for analyzing volume fraction fluctuations for a set of measuring windows [Chieco et al., Phys. Rev. E 96, 032909 (2017)., 10.1103/PhysRevE.96.032909]. This length permits a direct connection to the nature of disorder in the spatial configuration of the particles and provides a way to diagnose the degree of hyperuniformity in terms of the scaling of h and its value in comparison with established bounds. Here, this approach is generalized for extended particles, which are larger than the image resolution and can lie partially inside and partially outside the measuring windows. The starting point is an expression for the relative volume fraction variance in terms of four distinct volumes: that of the particle, the measuring window, the mean-squared overlap between particle and region, and the region over which particles have nonzero overlap with the measuring window. After establishing limiting behaviors for the relative variance, computational methods are developed for both continuum and pixelated particles. Exact results are presented for particles of special shape and for measuring windows of special shape, for which the equations are tractable. Comparison is made for other particle shapes, using simulated Poisson patterns. And the effects of polydispersity and image errors are discussed. For small measuring windows, both particle shape and spatial arrangement affect the form of the variance. For large regions, the variance scaling depends only on arrangement but particle shape sets the numerical proportionality. The combined understanding permit the measured variance to be translated to the spectrum of hyperuniformity lengths versus region size, as the quantifier of spatial arrangement. This program is demonstrated for a system of nonoverlapping particles at a series of increasing packing fractions as well as for an Einstein pattern of particles with several different extended shapes.

  1. Measuring the attenuation length in liquid scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Hellgartner, Dominikus; Oberauer, Lothar; Prummer, Sabrina; Sawatzki, Julia; Zimmer, Vincenz [Technische Universitaet Muenchen, Physik Departement E15, James Franck Strasse, 85748 Garching (Germany); Ulrich, Andreas [Technische Universitaet Muenchen, Physik Departement E12, James Franck Strasse, 85748 Garching (Germany)

    2015-07-01

    The next generation of liquid scintillator detectors like the proposed LENA detector or the planned JUNO detector will feature diameters of order 30 m. Due to this vast size, the optical quality of the scintillator is of crucial importance. To determine the attenuation length of liquid scintillators, an experiment with a 5 m long measurement section was set-up in the underground laboratory in Garching. The current set-up of the experiment is presented along with a discussion of the results of the first measurements. Additionally, there is an outlook towards possible upgrades of the experiment in the future.

  2. Length Scales in Bayesian Automatic Adaptive Quadrature

    Directory of Open Access Journals (Sweden)

    Adam Gh.

    2016-01-01

    Full Text Available Two conceptual developments in the Bayesian automatic adaptive quadrature approach to the numerical solution of one-dimensional Riemann integrals [Gh. Adam, S. Adam, Springer LNCS 7125, 1–16 (2012] are reported. First, it is shown that the numerical quadrature which avoids the overcomputing and minimizes the hidden floating point loss of precision asks for the consideration of three classes of integration domain lengths endowed with specific quadrature sums: microscopic (trapezoidal rule, mesoscopic (Simpson rule, and macroscopic (quadrature sums of high algebraic degrees of precision. Second, sensitive diagnostic tools for the Bayesian inference on macroscopic ranges, coming from the use of Clenshaw-Curtis quadrature, are derived.

  3. Scale Length of the Galactic Thin Disk

    Indian Academy of Sciences (India)

    D. Κ. Ojha

    2000-06-01

    This paper presents an analysis of the first 2MASS (The Two Micron All Sky Survey) sampler data as observed at lower Galactic latitude in our Galaxy. These new near-infrared data provide insight into the structure of the thin disk of our Galaxy, The interpretation of star counts and color distributions of stars in the near-infrared with the synthetic stellar population model, gives strong evidence that the Galactic thin disk density scale length, ℎ, is rather short (2.7 ± 0.1 kpc).

  4. Length spectra and degeneration of flat metrics

    CERN Document Server

    Duchin, Moon; Rafi, Kasra

    2009-01-01

    In this paper we consider flat metrics (semi-translation structures) on surfaces of finite type. There are two main results. The first is a complete description of when a set of simple closed curves is spectrally rigid, that is, when the length vector determines a metric among the class of flat metrics. Secondly, we give an embedding into the space of geodesic currents and use this to get a boundary for the space of flat metrics. The geometric interpretation is that flat metrics degenerate to "mixed structures" on the surface: part flat metric and part measured foliation.

  5. Asymptotic Safety, Emergence and Minimal Length

    CERN Document Server

    Percacci, R

    2010-01-01

    There seems to be a common prejudice that asymptotic safety is either incompatible with, or at best unrelated to, the other topics in the title. This is not the case. In fact, we show that 1) the existence of a fixed point with suitable properties is a promising way of deriving emergent properties of gravity, and 2) there is a precise sense in which asymptotic safety implies a minimal length. In so doing we also discuss possible signatures of asymptotic safety in scattering experiments.

  6. Crack Length Detection by Digital Image Processing

    DEFF Research Database (Denmark)

    Lyngbye, Janus; Brincker, Rune

    1990-01-01

    It is described how digital image processing is used for measuring the length of fatigue cracks. The system is installed in a Personal Computer equipped with image processing hardware and performs automated measuring on plane metal specimens used in fatigue testing. Normally one can not achieve...... a resolution better then that of the image processing equipment. To overcome this problem an extrapolation technique is used resulting in a better resolution. The system was tested on a specimen loaded with different loads. The error σa was less than 0.031 mm, which is of the same size as human measuring...

  7. Length Scaling of Shear Zones at the Frictional-Viscous Transition (FVT)

    Science.gov (United States)

    Schrank, C. E.; Handy, M. R.; Fusseis, F.

    2005-12-01

    We present a new method for determining the characteristic length scales of strain localization in crustal scale shear zones. This entails determining two parameters that describe the degree of strain heterogeneity in natural shear zones: (1) the strain localization factor, LfRA, defined as the ratio of the shear zone area to a chosen reference area, ARA, and (2) the relative localization intensity, Iloc, a function of the ratio of the mean shear strain to the maximum shear strain measured in a transect of the shear zone. ARA is a geometric homogenization scale determined from autocorrelation functions (ACF) of 2-D images (thin sections, foliation maps and aerial photographs) of shear zone networks on different scales that formed during a single deformational event. When applied to shear zones from a well exposed segment of the frictional-to-viscous transition (FVT) in NE Spain, we found that maxima in LfRA on the mm, cm, m and km scales coincided with the length scales of existing mineralogical and lithological heterogeneities. On any of these characteristic length scales, Iloc increased both along and across the length of the shear zones, suggesting that the shear zones weakening as a function of time and strain. This is consistent with structural evidence for progressive weakening of the crust on the characteristic length scales of strain heterogeneity.

  8. Laboratory investigation of the effect of a new labyrinth with different length and width in the wing length of a triangular-shaped labyrinth weir

    Directory of Open Access Journals (Sweden)

    Amirreza Bahrebar

    2016-09-01

    Full Text Available Due to minor changes in the static load on the crest in case of large fluctuations in flow rate, polyhedral weirs, compared with other types of weirs, are considered as economic structures to control water levels in the irrigation networks. Using labyrinth weirs is an effective and economical approach to improve the efficiency of the weir by increasing its effective crest length. In this case, for a constant hydraulic height and width, it passes a greater discharge in comparison with other types of weirs. In this study, the V-shaped plan-form weirs are studied [1, 2]. Tests are conducted on 30 models with 7 different discharges, and in a total of 210 tests. The models include 30 V-shaped weirs with various lengths. The models are investigated in a flume with 8 m length, 0.35 m width and height of 0.40 m. The results of this study indicate that for all triangular-shaped weirs the ratio of discharge coefficient to P/ ( : total hydraulic load, P: weir height is at first increased and after reaching a maximum, begins to be reduced. As the height of labyrinth on the weir wings increases, as a result of increases in effective length, the discharge coefficient is increased for a specific /P. The results also show that increasing the wing length reduces the discharge coefficient. Also, the discharge coefficient is greater for V-shaped weirs than linear ones.

  9. Biosynthesis of Polyhydroxyalkanoates Consisting of Short-chain-length Monomers and Medium-chain-length Monomers by Pseudomonas YS1

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    A strain capable of producing polyhydroxyalkanoates (PHAs) consisting of short- and medium-chain-length monomers was identified as Pseudomonas sp.coded as YS1.The strain synthesized PHAs containing monomers of hydroxybutyrate(HB or C4) and/or hydroxyoctanoate (HO or C8) and/or hydroxydecanoate (HD or C10) when grown in various substrates including glucose, raw sugar, molasses and various fatty acids.It was found that growth temperature affected the HB and HO monomer contents in the PHA.HB content in PHA increased from mole fraction 69% at 26℃ to mole fraction 85% at 37℃ while HO content decreased from mole fraction 29% at 26℃ to mole fraction 12% at 37℃.The temperature effect provides a simple and effective way to control the PHA composition and hence control the PHA mechanical and other physical properties.Also, the fermentor experiment indicated that PHB formation was growth associated and HO monomer production was in fact promoted by N-limitation.This conclusion was further supported by the fact that the formation of PHB only polyester was observed only when C/N molar ratio was smaller than 20.Higher C/N ratio led to the formation of HO monomers in the polyesters.

  10. The association between social factors and body length proportions in Polish schoolchildren from Lower Silesia

    Directory of Open Access Journals (Sweden)

    Kozieł Sławomir

    2016-12-01

    Full Text Available Many studies worldwide have shown that social factors are significantly associated with growth in childhood. However, very few researchers studied influence of social factors on body length proportions. The aim of the present study was the assessment how urbanization level, sibship size and parental education may affect body length proportions in schoolchildren. 325 boys and 335 girls aged 7-18 years were measured in schools in Wrocław, two small towns and villages around these towns. Height, sitting height, leg length , and lower leg length were measured in all children, then relative lengths (in relation to height were calculated: leg, femur, lower leg, estimated leg and lower leg length to leg length ratio. Height was standardized on age using LMS parameters for CDC 2002 year cohort. Other indices were standardized on age by using residuals variance derived from linear regressions. Four-way analysis of variance was used for height and each index, where independent variables were four social factors. Except for father’s education in boys, no other social factor was significant associated with height. Urbanization level significantly differed almost all indices, whereas father’s education level was significantly associated with relative leg length in girls and estimated leg length in both sexes. Our study has shown that the segments of lower limb seems to be more sensitive than height to the effect of social factors. In Lower Silesia, the level of urbanization is still related to differences in environmental conditions, enough to significantly affect growth of children, especially within the segments of lower limbs.

  11. Preferred Length of Video Segments in Interactive Video Programs.

    Science.gov (United States)

    Verhagen, P. W.

    This study investigated questions related to the length of video segments in interactive video programs: (1) the preferred segment length if learners decide how much information they want presented before stopping to answer question; (2) the relationship between segment length and direct recall of factual information when segment length is…

  12. 7 CFR 51.577 - Average midrib length.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Average midrib length. 51.577 Section 51.577... STANDARDS) United States Standards for Celery Definitions § 51.577 Average midrib length. Average midrib length means the average length of all the branches in the outer whorl measured from the point...

  13. Females Have Larger Ratio of Second‐to‐Fourth Digits Than Males in Four Species of Salamandridae, Caudata

    National Research Council Canada - National Science Library

    Kaczmarski, Mikołaj; Kubicka, Anna Maria; Tryjanowski, Piotr; Hromada, Martin

    2015-01-01

    Digit ratio (2D:4D) denotes the relative length of the second and fourth digits. It is considered to be a suitable biomarker of the in utero balance of fetal sex hormones, which affect early development...

  14. ESTIMATION OF STATURE BASED ON FOOT LENGTH

    Directory of Open Access Journals (Sweden)

    Vidyullatha Shetty

    2015-01-01

    Full Text Available BACKGROUND : Stature is the height of the person in the upright posture. It is an important measure of physical identity. Estimation of body height from its segments or dismember parts has important considerations for identifications of living or dead human body or remains recovered from disasters or other similar conditions. OBJECTIVE : Stature is an important indicator for identification. There are numerous means to establish stature and their significance lies in the simplicity of measurement, applicability and accuracy in prediction. Our aim of the study was to review the relationship between foot length and body height. METHODS : The present study reviews various prospective studies which were done to estimate the stature. All the measurements were taken by using standard measuring devices and standard anthropometric techniques. RESULTS : This review shows there is a correlation between stature and foot dimensions it is found to be positive and statistically highly significant. Prediction of stature was found to be most accurate by multiple regression analysis. CONCLUSIONS : Stature and gender estimation can be done by using foot measurements and stud y will help in medico - legal cases in establishing identity of an individual and this would be useful for Anatomists and Anthropologists to calculate stature based on foot length

  15. Bunch Length Measurements using Coherent Radiation

    CERN Document Server

    Ischebeck, Rasmus; Barnes, Christopher; Blumenfeld, Ian; Clayton, Chris; Decker, Franz Josef; Deng, Suzhi; Hogan, Mark; Huang Cheng Kun; Iverson, Richard; Johnson, Devon K; Krejcik, Patrick; Lu, Wei; Marsh, Kenneth; Oz, Erdem; Siemann, Robert; Walz, Dieter

    2005-01-01

    The accelerating field that can be obtained in a beam-driven plasma wakefield accelerator depends on the current of the electron beam that excites the wake. In the E-167 experiment, a peak current above 10kA will be delivered at a particle energy of 28GeV. The bunch has a length of a few ten micrometers and several methods are used to measure its longitudinal profile. Among these, autocorrelation of coherent transition radiation (CTR) is employed. The beam passes a thin metallic foil, where it emits transition radiation. For wavelengths greater than the bunch length, this transition radiation is emitted coherently. This amplifies the long-wavelength part of the spectrum. A scanning Michelson interferometer is used to autocorrelate the CTR. However, this method requires the contribution of many bunches to build an autocorrelation trace. The measurement is influenced by the transmission characteristics of the vacuum window and beam splitter. We present here an analysis of materials, as well as possible layouts ...

  16. Free path lengths in quasi crystals

    CERN Document Server

    Wennberg, Bernt

    2012-01-01

    The Lorentz gas is a model for a cloud of point particles (electrons) in a distribution of scatterers in space. The scatterers are often assumed to be spherical with a fixed diameter $d$, and the point particles move with constant velocity between the scatterers, and are specularly reflected when hitting a scatterer. There is no interaction between point particles. An interesting question concerns the distribution of free path lengths, i.e. the distance a point particle moves between the scattering events, and how this distribution scales with scatterer diameter, scatterer density and the distribution of the scatterers. It is by now well known that in the so-called Boltzmann-Grad limit, a Poisson distribution of scatters leads to an exponential distribution of free path lengths, whereas if the scatterer distribution is periodic, the distribution of free path behaves asymptotically like a Cauchy distribution. This paper considers the case when the scatters are distributed on a quasi crystal, i.e. non periodica...

  17. Cellular Mechanisms of Ciliary Length Control

    Directory of Open Access Journals (Sweden)

    Jacob Keeling

    2016-01-01

    Full Text Available Cilia and flagella are evolutionarily conserved, membrane-bound, microtubule-based organelles on the surface of most eukaryotic cells. They play important roles in coordinating a variety of signaling pathways during growth, development, cell mobility, and tissue homeostasis. Defects in ciliary structure or function are associated with multiple human disorders called ciliopathies. These diseases affect diverse tissues, including, but not limited to the eyes, kidneys, brain, and lungs. Many processes must be coordinated simultaneously in order to initiate ciliogenesis. These include cell cycle, vesicular trafficking, and axonemal extension. Centrioles play a central role in both cell cycle progression and ciliogenesis, making the transition between basal bodies and mitotic spindle organizers integral to both processes. The maturation of centrioles involves a functional shift from cell division toward cilium nucleation which takes place concurrently with its migration and fusion to the plasma membrane. Several proteinaceous structures of the distal appendages in mother centrioles are required for this docking process. Ciliary assembly and maintenance requires a precise balance between two indispensable processes; so called assembly and disassembly. The interplay between them determines the length of the resulting cilia. These processes require a highly conserved transport system to provide the necessary substances at the tips of the cilia and to recycle ciliary turnover products to the base using a based microtubule intraflagellar transport (IFT system. In this review; we discuss the stages of ciliogenesis as well as mechanisms controlling the lengths of assembled cilia.

  18. Localization length of nearly periodic layered metamaterials

    CERN Document Server

    del Barco, O

    2015-01-01

    We have analyzed numerically the localization length of light $\\xi$ for nearly periodic arrangements of homogeneous stacks (formed exclusively by right-handed materials) and mixed stacks (with alternating right and left-handed metamaterials). Layers with index of refraction $n_1$ and thickness $L_1$ alternate with layers of index of refraction $n_2$ and thickness $L_2$. Positional disorder has been considered by shifting randomly the positions of the layer boundaries with respect to periodic values. For homogeneous stacks, we have shown that the localization length is modulated by the corresponding bands and that $\\xi$ is enhanced at the center of each allowed band. In the limit of long-wavelengths $\\lambda$, the parabolic behavior previously found in purely disordered systems is recovered, whereas for $\\lambda \\ll L_1 + L_2$ a saturation is reached. In the case of nearly periodic mixed stacks with the condition $|n_1 L_1|=|n_2 L_2|$, instead of bands there is a periodic arrangement of Lorenztian resonances, ...

  19. Comment on ``Length-dependent translation of messenger RNA by ribosomes''

    Science.gov (United States)

    Zhang, Yunxin

    2012-02-01

    In a recent paper by Valleriani [Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.83.042903 83, 042903 (2011)], a simple model for the translation of messenger RNA (mRNA) is presented. Using this model, the protein translational ratio r, defined as the ratio of protein translation rate ωtl from mRNA to protein degradation rate ωp, is obtained. The key point in obtaining the translational ratio r is to get the protein translation rate ωtl. In Valleriani 's paper, ωtl is obtained as the mean value of the measured translation rate, which is the ratio of the synthesized protein number to the mRNA lifetime. However, in experiments, different methods might be used to obtain the value of ωtl. Therefore, to apply Valleriani 's model to more general experiments, in this Comment three methods to obtain the translation rate ωtl, and consequently the translational ratio r, are presented. Based on one of the methods which might be employed in most of the experiments, we find that the translational ratio r decays exponentially with mRNA length in prokaryotic cells, and decays reciprocally with mRNA length in eukaryotic cells. This result is slight different from that which was obtained in Valleriani 's paper.

  20. Training Sequence Length Optimization for a Turbo-Detector Using Decision-Directed Channel Estimation

    Directory of Open Access Journals (Sweden)

    Imed Hadj Kacem

    2008-01-01

    Full Text Available We consider the problem of optimization of the training sequence length when a turbo-detector composed of a maximum a posteriori (MAP equalizer and a MAP decoder is used. At each iteration of the receiver, the channel is estimated using the hard decisions on the transmitted symbols at the output of the decoder. The optimal length of the training sequence is found by maximizing an effective signal-to-noise ratio (SNR taking into account the data throughput loss due to the use of pilot symbols.

  1. Performances of carbon nanotube field effect transistors with altered channel length

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been studied.Buffered oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back gate.Channel length of the CNT-FETs was changed along with the etching process.The dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mobility,current ON/OFF ratio,etc.The results indicate that the devices still keep good quality.

  2. Variable Frame Rate and Length Analysis for Data Compression in Distributed Speech Recognition

    DEFF Research Database (Denmark)

    Kraljevski, Ivan; Tan, Zheng-Hua

    2014-01-01

    This paper addresses the issue of data compression in distributed speech recognition on the basis of a variable frame rate and length analysis method. The method first conducts frame selection by using a posteriori signal-to-noise ratio weighted energy distance to find the right time resolution...... length for steady regions. The method is applied to scalable source coding in distributed speech recognition where the target bitrate is met by adjusting the frame rate. Speech recognition results show that the proposed approach outperforms other compression methods in terms of recognition accuracy...... for noisy speech while achieving higher compression rates....

  3. Length of hospice enrollment and subsequent depression in family caregivers: 13-month follow-up study.

    Science.gov (United States)

    Kris, Alison E; Cherlin, Emily J; Prigerson, Holly; Carlson, Melissa D A; Johnson-Hurzeler, Rosemary; Kasl, Stanislav V; Bradley, Elizabeth H

    2006-03-01

    Although more people are using hospice than ever before, the average length of hospice enrollment is decreasing. Little is known about the effect of hospice length of enrollment on surviving family caregivers. The authors examine the association between patient length of hospice enrollment and major depressive disorder (MDD) among the surviving primary family caregivers 13 months after the patient's death. The authors conducted a three-year longitudinal study of 175 primary family caregivers of patients with terminal cancer who consecutively enrolled in the participating hospice from October 1999 through September 2001. Interviews were conducted with the primary family caregiver when the patient first enrolled with hospice and again 13 months after the patient's death. The authors used multivariate logistic regression models to estimate caregivers' adjusted risk at 13 months postloss for MDD, assessed using the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID). The effect of very short hospice length of enrollment (three days or less) compared with longer lengths of enrollment on caregiver MDD 13 months after their loss was nonsignificant in unadjusted analyses. The adjusted risk of MDD was significantly elevated for caregivers of patients who had very short hospice enrollments (adjusted odds ratio: 8.76, 95%confidence interval: 1.09-70.19) only after adjusting for baseline MDD, caregiver gender, caregiver age, kinship relationship to patient, caregiver education, caregiver chronic conditions, and caregiver burden. The adjustment for caregiver burden resulted in the greatest increase in odds ratio for very short hospice length of enrollment on risk of caregiver MDD 13 months after the loss. This study identifies a potential target group of family caregivers, characterized by hospice length of enrollment and several caregiver features, who might be most in need of mental health interventions.

  4. Leg Length, Body Proportion, and Health: A Review with a Note on Beauty

    Directory of Open Access Journals (Sweden)

    Maria Inês Varela-Silva

    2010-03-01

    Full Text Available Decomposing stature into its major components is proving to be a useful strategy to assess the antecedents of disease, morbidity and death in adulthood. Human leg length (femur + tibia, sitting height (trunk length + head length and their proportions, for example, (leg length/stature, or the sitting height ratio (sitting height/stature × 100, among others are associated with epidemiological risk for overweight (fatness, coronary heart disease, diabetes, liver dysfunction and certain cancers. There is also wide support for the use of relative leg length as an indicator of the quality of the environment for growth during infancy, childhood and the juvenile years of development. Human beings follow a cephalo-caudal gradient of growth, the pattern of growth common to all mammals. A special feature of the human pattern is that between birth and puberty the legs grow relatively faster than other post-cranial body segments. For groups of children and youth, short stature due to relatively short legs (i.e., a high sitting height ratio is generally a marker of an adverse environment. The development of human body proportions is the product of environmental x genomic interactions, although few if any specific genes are known. The HOXd and the short stature homeobox-containing gene (SHOX are genomic regions that may be relevant to human body proportions. For example, one of the SHOX related disorders is Turner syndrome. However, research with non-pathological populations indicates that the environment is a more powerful force influencing leg length and body proportions than genes. Leg length and proportion are important in the perception of human beauty, which is often considered a sign of health and fertility.

  5. Leg length, body proportion, and health: a review with a note on beauty.

    Science.gov (United States)

    Bogin, Barry; Varela-Silva, Maria Inês

    2010-03-01

    Decomposing stature into its major components is proving to be a useful strategy to assess the antecedents of disease, morbidity and death in adulthood. Human leg length (femur + tibia), sitting height (trunk length + head length) and their proportions, for example, (leg length/stature), or the sitting height ratio (sitting height/stature x 100), among others) are associated with epidemiological risk for overweight (fatness), coronary heart disease, diabetes, liver dysfunction and certain cancers. There is also wide support for the use of relative leg length as an indicator of the quality of the environment for growth during infancy, childhood and the juvenile years of development. Human beings follow a cephalo-caudal gradient of growth, the pattern of growth common to all mammals. A special feature of the human pattern is that between birth and puberty the legs grow relatively faster than other post-cranial body segments. For groups of children and youth, short stature due to relatively short legs (i.e., a high sitting height ratio) is generally a marker of an adverse environment. The development of human body proportions is the product of environmental x genomic interactions, although few if any specific genes are known. The HOXd and the short stature homeobox-containing gene (SHOX) are genomic regions that may be relevant to human body proportions. For example, one of the SHOX related disorders is Turner syndrome. However, research with non-pathological populations indicates that the environment is a more powerful force influencing leg length and body proportions than genes. Leg length and proportion are important in the perception of human beauty, which is often considered a sign of health and fertility.

  6. The relationship between telomere length and mortality in chronic obstructive pulmonary disease (COPD.

    Directory of Open Access Journals (Sweden)

    Jee Lee

    Full Text Available Some have suggested that chronic obstructive pulmonary disease (COPD is a disease of accelerated aging. Aging is characterized by shortening of telomeres. The relationship of telomere length to important clinical outcomes such as mortality, disease progression and cancer in COPD is unknown. Using quantitative polymerase chain reaction (qPCR, we measured telomere length of peripheral leukocytes in 4,271 subjects with mild to moderate COPD who participated in the Lung Health Study (LHS. The subjects were followed for approximately 7.5 years during which time their vital status, FEV(1 and smoking status were ascertained. Using multiple regression methods, we determined the relationship of telomere length to cancer and total mortality in these subjects. We also measured telomere length in healthy "mid-life" volunteers and patients with more severe COPD. The LHS subjects had significantly shorter telomeres than those of healthy "mid-life" volunteers (p<.001. Compared to individuals in the 4(th quartile of relative telomere length (i.e. longest telomere group, the remaining participants had significantly higher risk of cancer mortality (Hazard ratio, HR, 1.48; p = 0.0324 and total mortality (HR, 1.29; p = 0.0425. Smoking status did not make a significant difference in peripheral blood cells telomere length. In conclusion, COPD patients have short leukocyte telomeres, which are in turn associated increased risk of total and cancer mortality. Accelerated aging is of particular relevance to cancer mortality in COPD.

  7. The relationship between telomere length and mortality in chronic obstructive pulmonary disease (COPD).

    Science.gov (United States)

    Lee, Jee; Sandford, Andrew J; Connett, John E; Yan, Jin; Mui, Tammy; Li, Yuexin; Daley, Denise; Anthonisen, Nicholas R; Brooks-Wilson, Angela; Man, S F Paul; Sin, Don D

    2012-01-01

    Some have suggested that chronic obstructive pulmonary disease (COPD) is a disease of accelerated aging. Aging is characterized by shortening of telomeres. The relationship of telomere length to important clinical outcomes such as mortality, disease progression and cancer in COPD is unknown. Using quantitative polymerase chain reaction (qPCR), we measured telomere length of peripheral leukocytes in 4,271 subjects with mild to moderate COPD who participated in the Lung Health Study (LHS). The subjects were followed for approximately 7.5 years during which time their vital status, FEV(1) and smoking status were ascertained. Using multiple regression methods, we determined the relationship of telomere length to cancer and total mortality in these subjects. We also measured telomere length in healthy "mid-life" volunteers and patients with more severe COPD. The LHS subjects had significantly shorter telomeres than those of healthy "mid-life" volunteers (ptelomere length (i.e. longest telomere group), the remaining participants had significantly higher risk of cancer mortality (Hazard ratio, HR, 1.48; p = 0.0324) and total mortality (HR, 1.29; p = 0.0425). Smoking status did not make a significant difference in peripheral blood cells telomere length. In conclusion, COPD patients have short leukocyte telomeres, which are in turn associated increased risk of total and cancer mortality. Accelerated aging is of particular relevance to cancer mortality in COPD.

  8. REML estimates of genetic parameters of sexual dimorphism for wing and thorax length in Drosophila melanogaster

    Indian Academy of Sciences (India)

    Sandrine Mignon-Grasteau; Jean David; Patricia Gibert; Hélène Legout; Georges Pétavy; Brigitte Moreteau; Catherine Beaumont

    2004-08-01

    Restricted maximum likelihood was used to estimate genetic parameters of male and female wing and thorax length in isofemale lines of Drosophila melanogaster, and results compared to estimates obtained earlier with the classical analysis of variance approach. As parents within an isofemale line were unknown, a total of 500 parental pedigrees were simulated and mean estimates computed. Full and half sibs were distinguished, in contrast to usual isofemale studies in which animals were all treated as half sibs and hence heritability was overestimated. Heritability was thus estimated at 0.33, 0.38, 0.30 and 0.33 for male and female wing length and male and female thorax length, respectively, whereas corresponding estimates obtained using analysis of variance were 0.46, 0.54, 0.35 and 0.38. Genetic correlations between male and female traits were 0.85 and 0.62 for wing and thorax length, respectively. Sexual dimorphism and the ratio of female to male traits were moderately heritable (0.30 and 0.23 for wing length, 0.38 and 0.23 for thorax length). Both were moderately and positively correlated with female traits, and weakly and negatively correlated with male traits. Such heritabilities confirmed that sexual dimorphism might be a fast evolving trait in Drosophila.

  9. A Study of Relation of Stature with Foot Length in Natives of Gujarat State

    Directory of Open Access Journals (Sweden)

    Utsav Parekh

    2014-01-01

    Full Text Available Establishment of an identity is very much important in both civil and criminal cases. Stature is one of the criteria of personal identification. Many studies have shown that limbs exhibit consistent ratios relatives to the total height of a person. A very little work has been done for stature estimation from foot length in Gujarat state. So, the present study was carried out for estimation of stature from the foot length of total 200 medical students (116 Males and 84 Females in 17-21 years age group in dept of Forensic Medicine and Toxicology, Smt. N. H. L. Municipal Medical College, Ahmedabad, Gujarat. Stature and foot length measurements of each one of them were taken using standard instruments. Foot length was defined as straight distance from the most prominent part of the heel backwards (pternion to the most distal part of the longest toe (acropodian. Data was analyzed and a good correlation was observed and it was statistically highly significant (p<0.001. It was concluded that there is positive correlation between stature and foot length in a particular population and the estimation of stature among the population can be carried out using foot length. The result of the present study would be useful for anthropologists and Forensic Medicine Experts.

  10. Tolerance at arm's length: the Dutch experience.

    Science.gov (United States)

    Schuijer, J

    1990-01-01

    With respect to pedophilia and the age of consent, the Netherlands warrants special attention. Although pedophilia is not as widely accepted in the Netherlands as sometimes is supposed, developments in the judicial practice showed a growing reservedness. These developments are a spin-off of related developments in Dutch society. The tolerance in the Dutch society has roots that go far back in history and is also a consequence of the way this society is structured. The social changes of the sixties and seventies resulted in a "tolerance at arm's length" for pedophiles, which proved to be deceptive when the Dutch government proposed to lower the age of consent in 1985. It resulted in a vehement public outcry. The prevailing sex laws have been the prime target of protagonists of pedophile emancipation. Around 1960, organized as a group, they started to undertake several activities. In the course of their existence, they came to redefine the issue of pedophilia as one of youth emancipation.

  11. Length Scale of the Spin Seebeck Effect

    Science.gov (United States)

    Kehlberger, Andreas; Ritzmann, Ulrike; Hinzke, Denise; Guo, Er-Jia; Cramer, Joel; Jakob, Gerhard; Onbasli, Mehmet C.; Kim, Dong Hun; Ross, Caroline A.; Jungfleisch, Matthias B.; Hillebrands, Burkard; Nowak, Ulrich; Kläui, Mathias

    2015-08-01

    We investigate the origin of the spin Seebeck effect in yttrium iron garnet (YIG) samples for film thicknesses from 20 nm to 50 μ m at room temperature and 50 K. Our results reveal a characteristic increase of the longitudinal spin Seebeck effect amplitude with the thickness of the insulating ferrimagnetic YIG, which levels off at a critical thickness that increases with decreasing temperature. The observed behavior cannot be explained as an interface effect or by variations of the material parameters. Comparison to numerical simulations of thermal magnonic spin currents yields qualitative agreement for the thickness dependence resulting from the finite magnon propagation length. This allows us to trace the origin of the observed signals to genuine bulk magnonic spin currents due to the spin Seebeck effect ruling out an interface origin and allowing us to gauge the reach of thermally excited magnons in this system for different temperatures. At low temperature, even quantitative agreement with the simulations is found.

  12. Stellar mixing length theory with entropy rain

    CERN Document Server

    Brandenburg, Axel

    2015-01-01

    Stellar mixing length theory is modified to include the effects of a nongradient term that originates from the motion of convective elements with entropy perturbations of either sign. It is argued that such a term, first studied by Deardorff in the meteorological context, represents the effects of thin intense downdrafts caused by the rapid cooling in the granulation layer at the top of the convection zone. They transport heat nonlocally, as originally anticipated by Spruit in the 1990s, who describes the convection in the strongly stratified simulations of Stein & Nordlund as entropy rain. Although our model has ill-determined free parameters, it demonstrates that solutions can be found that look similar to the original ones, except that the deeper layers are now Schwarzschild stable, so no giant cells are produced and the typical convective scale is that of granules even at larger depth. Consequences for modeling solar differential, the global dynamo, and sunspots are briefly discussed.

  13. [Telomere length, telomerase activity, stress and aging].

    Science.gov (United States)

    Spivak, I M; Mikhelson, V M; Spivak, D L

    2015-01-01

    The review is dedicated to analysis of data available at present time concerning possible influence of stress upon telomere lengths and telomerase activity, as well as various ways of counteracting it. Present-day telomerase theory of aging gains a new impetus, shedding light upon the influence of psychological state of humans and their ability to counteract stress, upon the process of aging. It also tends to regard telomere shortening and the decrease in the activity of telomerase as a marker of level of the ability to adapt to both inner and outer influences. Both aging and age-dependent diseases are proved to be substantially retarded not only by the administration of drugs, but also by psychological means, which forms a good way towards healthy longevity. With complete understanding of the impossibility to prevent or even to slow down natural senescence itself, these methods allow to remove causes, which accelerate senescence, and to increase the average human longevity.

  14. Variable length Markov chains and dynamical sources

    CERN Document Server

    Cénac, Peggy; Paccaut, Frédéric; Pouyanne, Nicolas

    2010-01-01

    Infinite random sequences of letters can be viewed as stochastic chains or as strings produced by a source, in the sense of information theory. The relationship between Variable Length Markov Chains (VLMC) and probabilistic dynamical sources is studied. We establish a probabilistic frame for context trees and VLMC and we prove that any VLMC is a dynamical source for which we explicitly build the mapping. On two examples, the ``comb'' and the ``bamboo blossom'', we find a necessary and sufficient condition for the existence and the unicity of a stationary probability measure for the VLMC. These two examples are detailed in order to provide the associated Dirichlet series as well as the generating functions of word occurrences.

  15. The heritability of leucocyte telomere length dynamics

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Möller, Sören

    2015-01-01

    BACKGROUND: Leucocyte telomere length (LTL) is a complex trait associated with ageing and longevity. LTL dynamics are defined by LTL and its age-dependent attrition. Strong, but indirect evidence suggests that LTL at birth and its attrition during childhood largely explains interindividual LTL...... unique environmental factors, estimated at 72% (95% CI 56% to 84%) affected LTL attrition rate with no indication of shared environmental effects. CONCLUSIONS: This is the first study that estimated heritability of LTL and also its age-dependent attrition. As LTL attrition is much slower in adults than...... in children and given that having a long or a short LTL is largely determined before adulthood, our findings suggest that heritability and early life environment are the main determinants of LTL throughout the human life course. Thus, insights into factors that influence LTL at birth and its dynamics during...

  16. Telomerase and telomere length in pulmonary fibrosis.

    Science.gov (United States)

    Liu, Tianju; Ullenbruch, Matthew; Young Choi, Yoon; Yu, Hongfeng; Ding, Lin; Xaubet, Antoni; Pereda, Javier; Feghali-Bostwick, Carol A; Bitterman, Peter B; Henke, Craig A; Pardo, Annie; Selman, Moises; Phan, Sem H

    2013-08-01

    In addition to its expression in stem cells and many cancers, telomerase activity is transiently induced in murine bleomycin (BLM)-induced pulmonary fibrosis with increased levels of telomerase transcriptase (TERT) expression, which is essential for fibrosis. To extend these observations to human chronic fibrotic lung disease, we investigated the expression of telomerase activity in lung fibroblasts from patients with interstitial lung diseases (ILDs), including idiopathic pulmonary fibrosis (IPF). The results showed that telomerase activity was induced in more than 66% of IPF lung fibroblast samples, in comparison with less than 29% from control samples, some of which were obtained from lung cancer resections. Less than 4% of the human IPF lung fibroblast samples exhibited shortened telomeres, whereas less than 6% of peripheral blood leukocyte samples from patients with IPF or hypersensitivity pneumonitis demonstrated shortened telomeres. Moreover, shortened telomeres in late-generation telomerase RNA component knockout mice did not exert a significant effect on BLM-induced pulmonary fibrosis. In contrast, TERT knockout mice exhibited deficient fibrosis that was independent of telomere length. Finally, TERT expression was up-regulated by a histone deacetylase inhibitor, while the induction of TERT in lung fibroblasts was associated with the binding of acetylated histone H3K9 to the TERT promoter region. These findings indicate that significant telomerase induction was evident in fibroblasts from fibrotic murine lungs and a majority of IPF lung samples, whereas telomere shortening was not a common finding in the human blood and lung fibroblast samples. Notably, the animal studies indicated that the pathogenesis of pulmonary fibrosis was independent of telomere length.

  17. SURVIVAL ANALYSIS AND LENGTH-BIASED SAMPLING

    Directory of Open Access Journals (Sweden)

    Masoud Asgharian

    2010-12-01

    Full Text Available When survival data are colleted as part of a prevalent cohort study, the recruited cases have already experienced their initiating event. These prevalent cases are then followed for a fixed period of time at the end of which the subjects will either have failed or have been censored. When interests lies in estimating the survival distribution, from onset, of subjects with the disease, one must take into account that the survival times of the cases in a prevalent cohort study are left truncated. When it is possible to assume that there has not been any epidemic of the disease over the past period of time that covers the onset times of the subjects, one may assume that the underlying incidence process that generates the initiating event times is a stationary Poisson process. Under such assumption, the survival times of the recruited subjects are called “lengthbiased”. I discuss the challenges one is faced with in analyzing these type of data. To address the theoretical aspects of the work, I present asymptotic results for the NPMLE of the length-biased as well as the unbiased survival distribution. I also discuss estimating the unbiased survival function using only the follow-up time. This addresses the case that the onset times are either unknown or known with uncertainty. Some of our most recent work and open questions will be presented. These include some aspects of analysis of covariates, strong approximation, functional LIL and density estimation under length-biased sampling with right censoring. The results will be illustrated with survival data from patients with dementia, collected as part of the Canadian Study of Health and Aging (CSHA.

  18. Burnout among physiotherapists and length of service

    Directory of Open Access Journals (Sweden)

    Zbigniew Śliwiński

    2014-04-01

    Full Text Available Objectives: The aim of this study was to identify factors that contribute to the development of burnout among physiotherapists with different length of service in physiotherapy. Material and Methods: The following research tools were used to study burnout: the Life Satisfaction Questionnaire (LSQ, based on FLZ (Fragebogen zur Lebenszufriedenheit by Frahrenberg, Myrtek, Schumacher, and Brähler; the Burnout Scale Inventory (BSI by Steuden and Okła; and an ad hoc questionnaire to collect socio-demographic data. The survey was anonymous and voluntary and involved a group of 200 active physiotherapists working in Poland. Results: A statistical analysis revealed significant differences in overall life satisfaction between length-of-service groups (p = 0.03. Physiotherapists with more than 15 years of service reported greater satisfaction than those with less than 5 years and between 5 and 15 years of service. The results suggest that burnout in those with 5-15 years of service is higher in physiotherapists working in health care centers and increases with age and greater financial satisfaction, while it decreases with greater satisfaction with friend and family relations and greater satisfaction with one's work and profession. In those with more than 15 years of service, burnout increases in the case of working in a setting other than a health care or educational center and decreases with greater satisfaction with one's work and profession. Conclusions: Job satisfaction and a satisfying family life prevent burnout among physiotherapists with 5-15 years of service in the profession. Financial satisfaction, age and being employed in health care may cause burnout among physiotherapists with 5-15 years of service. Physiotherapists with more than 15 years of service experience more burnout if they work in a setting other than a health care or educational center and less burnout if they are satisfied with their profession.

  19. Obesity, diabetes, and length of time in the United States

    Science.gov (United States)

    Tsujimoto, Tetsuro; Kajio, Hiroshi; Sugiyama, Takehiro

    2016-01-01

    Abstract Obesity prevalence remains high in the United States (US), and is rising in most other countries. This is a repeated cross-sectional study using a nationally representative sample of the National Health and Nutrition Examination Survey 1999 to 2012. Multivariate logistic regression analyses were separately performed for adults (n = 37,639) and children/adolescents (n = 28,282) to assess the associations between the length of time in the US, and the prevalences of obesity and diabetes. In foreign-born adults, the prevalences of both obesity and diabetes increased with the length of time in the US, and ≥20 years in the US was associated with significantly higher rates of obesity (adjusted odds ratio [aOR] 2.32, 95% confidence interval [CI] 1.22–4.40, P = 0.01) and diabetes (aOR 4.22, 95% CI 1.04–17.08, P = 0.04) compared with obesity prevalence was significantly higher in those born in the US than those who had been in the US for obesity prevalence was significantly higher in US-born than in foreign-born adults from 1999 to 2012. On the other hand, the gap in obesity prevalence between US-born and foreign-born children/adolescents decreased from 1999 to 2011 due to a rapid increase in obesity prevalence among the foreign-born population, until there was no significant difference in 2011 to 2012. This study revealed that the risks of obesity and diabetes have increased in foreign-born US residents with time living in the US. However, the obesity gap between US-born and foreign-born populations is closing. PMID:27583867

  20. Pharmacologically induced erect penile length and stretched penile lengh are both good predictors of post-inflatable prosthesis penile length

    Science.gov (United States)

    Osterberg, EC; Maganty, A; Ramasamy, R; Eid, JF

    2015-01-01

    Inflatable penile prosthesis (IPP) remains the gold standard for the surgical treatment of refractory erectile dysfunction; however, current literature to aid surgeons on how best to counsel patients on their postoperative inflated penile length is lacking. The aim of this study was to identify preoperative parameters that could better predict postoperative penile length following insertion of an IPP. Twenty men were enrolled in a prospective study examining penile lengths before and after IPP surgery. Patients with Peyronie’s disease were excluded from this analysis. Baseline preoperative characteristics, including body mass index, history of hypertension, diabetes, Sexual Health Inventory for Men scores and/or prior radical prostatectomy were recorded. All patients underwent implantation with a three-piece inflatable Coloplast penile prosthesis. We compared stretched penile length to pharmacologically induced erect lengths. Postoperatively, we measured inflated penile lengths at 6 weeks and assessed patients’ perception of penile size at 12 weeks. The median (± interquartile range) stretched penile length and pharmacologically induced erect penile length was 15 (± 3) and 14.25 (± 2) cm, respectively (P = 0.5). Median post-prosthesis penile length (13.5 ± 2.13 cm) was smaller than preoperative pharmacologically induced length (P = 0.02) and preoperative stretched penile length (P = 0.01). The majority of patients (70%) had a decrease in penile length (median loss 0.5 ± 1.5 cm); however, this loss was perceptible by 43% of men. Stretched penile length and pharmacologically induced erect penile length were equally good predictors of postoperative inflated length (Spearman’s correlation 0.8 and 0.9, respectively). Pharmacologically induced erect penile length and stretched penile lengths are equal predictors of post-prosthesis penile length. The majority of men will experience some decrease in penile length following prosthesis implantation; however <50

  1. CROSS SECTIONAL STUDY OF SECOND AND FOURTH DIGIT RATIO WITH PHYSICAL ATTRIBUTES IN SOUTH INDIAN POPULATION

    Directory of Open Access Journals (Sweden)

    Meera Jacob

    2015-06-01

    Full Text Available Background: Study of the index (2D and ring (4D digit ratios and their association with some physical characteristics of South Indian Population was done to determine the values of 2D:4D digit ratios and their association with other anthropometric variables. Materials and Methods: 160 adults (80 males and 80 females between ages of 18 years and above were randomly selected with exclusion of those with hand deformities. The digit lengths were measured from the basal crease to the tips using vernier calipers. The 2D:4D ratios were determined for each subject while height and weight were used to calculate the body mass index and data analyzed. Results: The results showed significant difference in 2D:4D ratio between males and females. (p<0.001. Mean height of males exceeded the mean height of females and the mean weight of males exceeded the mean weight of females .Mean BMI of males also exceeded that of females. There was a positive correlation between the second digit length and Height and weight in males and females both on right and left sides. There was also a significant correlation weight and second digit length in males.The 2D:4D ratio for both left and right hand did not show any positive correlation with height, weight or BMI of an individual from people of South India. Conclusion: The results show a positive correlation between the digit lengths and height in both males and females and between weight and second digit length in case of males but the 2D:4D digit ratio had no relationship to height ,weight or BMI.The analysis also demonstrated that the males have greater 2D:4D ratio compared to females. The results of the study can be of importance in the field of forensic anthropology.

  2. No Sexual Dimorphism Detected in Digit Ratios of the Fire Salamander (Salamandra salamandra).

    Science.gov (United States)

    Balogová, Monika; Nelson, Emma; Uhrin, Marcel; Figurová, Mária; Ledecký, Valent; Zyśk, Bartłomiej

    2015-10-01

    It has been proposed that digit ratio may be used as a biomarker of early developmental effects. Specifically, the second-to-fourth digit ratio (2D:4D) has been linked to the effects of sex hormones and their receptor genes, but other digit ratios have also been investigated. Across taxa, patterns of sexual dimorphism in digit ratios are ambiguous and a scarcity of studies in basal tetrapods makes it difficult to understand how ratios have evolved. Here, we focus on examining sex differences in digit ratios (2D:3D, 2D:4D, and 3D:4D) in a common amphibian, the fire salamander (Salamandra salamandra). We used graphic software to measure soft tissue digit length and digit bone length from X-rays. We found a nonsignificant tendency in males to have a lower 2D:3D than females; however, no sexual differences were detected in the other ratios. We discuss our results in the context of other studies of digit ratios, and how sex determination systems, as well as other factors, might impact patterns of sexual dimorphism, particularly in reptiles and in amphibians. Our findings suggest that caution is needed when using digit ratios as a potential indicator of prenatal hormonal effects in amphibians and highlight the need for more comparative studies to elucidate the evolutionary and genetic mechanisms implicated in sexually dimorphic patterns across taxonomic groups. © 2015 Wiley Periodicals, Inc.

  3. Position of the patella in adults in central India: evaluation of the Insall-Salvati ratio.

    Science.gov (United States)

    Upadhyay, Sachin; Raza, H K T; Srivastava, Pranay

    2013-04-01

    To assess the Insall-Salvati ratio in normal Indian adults to determine its applicability and the incidence of patella alta and baja in Indian populations. 800 knees in 200 men and 200 women aged 18 to 50 (mean, 30) years were evaluated using lateral radiographs. The knee was set in semi-flexion (30º) to enable good visualisation of the patellar tendon and its insertion into the tibia on radiographs. The length of the patellar tendon (LT) over the length of the patella (LP)-the Insall-Salvati ratio-was measured, using a vernier caliper. The mean LT/LP ratio was 1.14 (standard deviation, 0.18). Based on the 95% confidence interval, the ratio was considered normal if within ±40%. The LT/LP ratio was significantly higher in females than males (1.17 vs. 1.12, ppatella alta was significantly greater in our Indian subjects than in western subjects (>1.5 vs. >1.2, ppatella alta (ratio, >1.5) and patella baja (ratio, <0.7) were 2.8% and 1%, respectively. The use of the Insall-Salvati ratio to determine the patellar position is less applicable to Indian populations in which squatting, sitting cross-legged, and kneeling are customs. We propose that the normal range of the ratio for squatters among Indian populations be 0.7 to 1.5.

  4. Fault zone rheology and length scales of frictional failure

    Science.gov (United States)

    Fagereng, A.

    2011-12-01

    Faults have a finite thickness and commonly contain fault rocks of heterogeneous composition, leading to rheological contrasts between intermingled lithologies (at the macroscale) and minerals (at the microscale) within the fault zone. The distribution and volumetric ratio of materials with different viscosity, frictional behavior, and preferred deformation mechanism, may therefore be a critical factor controlling the bulk rheology of heterogeneous fault zones. For example, at subgreenschist facies metamorphic conditions, fine-grained phyllosilicate-dominated mudstones tend to experience viscous shearing flow by dissolution-precipitation creep, whereas coarse grained quartz-dominated sandstones tend to act like competent, brittle volumes. In the rock record, deformation of mixed lithologies is well represented in tectonic mélanges. The subgreenschist facies (P defined by slickenfibre-coated shear surfaces linked by quartz-calcite extension veins. The frequency-size distribution of competent lenses (phacoids) in the Chrystalls Beach Complex follows a power-law distribution and is scale-invariant. The exponent of the power-law distribution varies with dominant deformation style, and is high in zones of dominantly continuous deformation - relating to a high matrix fraction, predominance of small phacoids, and small phacoid aspect ratios, whereas a low power-law exponent relates to a small matrix fraction and localized deformation accommodated on shear discontinuities. This variation in power-law exponent indicates that whether deformation occurs predominantly by continuous or discontinuous deformation may be predicted from the shape of the frequency-size distribution of competent lenses, and supports the hypothesis that bulk rheology is determined by the volume fraction of competent material. The distribution of competent material likely affects the seismic style of actively deforming fault zones. The length scales of shear discontinuities are likely to be a factor

  5. Evaluating outer segment length as a surrogate measure of peak foveal cone density.

    Science.gov (United States)

    Wilk, Melissa A; Wilk, Brandon M; Langlo, Christopher S; Cooper, Robert F; Carroll, Joseph

    2017-01-01

    Adaptive optics (AO) imaging tools enable direct visualization of the cone photoreceptor mosaic, which facilitates quantitative measurements such as cone density. However, in many individuals, low image quality or excessive eye movements precludes making such measures. As foveal cone specialization is associated with both increased density and outer segment (OS) elongation, we sought to examine whether OS length could be used as a surrogate measure of foveal cone density. The retinas of 43 subjects (23 normal and 20 albinism; aged 6-67years) were examined. Peak foveal cone density was measured using confocal adaptive optics scanning light ophthalmoscopy (AOSLO), and OS length was measured using optical coherence tomography (OCT) and longitudinal reflectivity profile-based approach. Peak cone density ranged from 29,200 to 214,000cones/mm(2) (111,700±46,300cones/mm(2)); OS length ranged from 26.3 to 54.5μm (40.5±7.7μm). Density was significantly correlated with OS length in albinism (pdensity as a function of OS length was created based on histology and optimized to fit the albinism data. The model includes triangular cone packing, a cylindrical OS with a fixed volume of 136.6μm(3), and a ratio of OS to inner segment width that increased linearly with increasing OS length (R(2)=0.72). Normal subjects showed no apparent relationship between cone density and OS length. In the absence of adequate AOSLO imagery, OS length may be used to estimate cone density in patients with albinism. Whether this relationship exists in other patient populations with foveal hypoplasia (e.g., premature birth, aniridia, isolated foveal hypoplasia) remains to be seen. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Oxygen isotopic ratios in intermediate-mass red giants

    CERN Document Server

    Lebzelter, Thomas; Hinkle, Kenneth; Nowotny, Walter; Aringer, Bernhard

    2015-01-01

    Context. The abundances of the three main isotopes of oxygen are altered in the course of the CNO-cycle. When the first dredge-up mixes the burning products to the surface, the nucleosynthesis processes can be probed by measuring oxygen isotopic ratios. Aims. By measuring 16O/17O and 16O/18O in red giants of known mass we compare the isotope ratios with predictions from stellar and galactic evolution modelling. Methods. Oxygen isotopic ratios were derived from the K-band spectra of six red giants. The sample red giants are open cluster members with known masses of between 1.8 and 4.5 Msun . The abundance determination employs synthetic spectra calculated with the COMARCS code. The effect of uncertainties in the nuclear reaction rates, the mixing length, and of a change in the initial abundance of the oxygen isotopes was determined by a set of nucleosynthesis and mixing models using the FUNS code. Results. The observed 16O/17O ratios are in good agreement with the model results, even if the measured values do ...

  7. 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.

  8. Selective breeding for a behavioral trait changes digit ratio.

    Directory of Open Access Journals (Sweden)

    Reginia H Y Yan

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

  9. Temperature dependence of the slip length in polymer melts at attractive surfaces.

    Science.gov (United States)

    Servantie, J; Müller, M

    2008-07-11

    Using Couette and Poiseuille flows, we extract the temperature dependence of the slip length, delta, from molecular dynamics simulations of a coarse-grained polymer model in contact with an attractive surface. delta is dictated by the ratio of bulk viscosity and surface mobility. At weakly attractive surfaces, lubrication layers form; delta is large and increases upon cooling. Close to the glass transition temperature Tg, very large slip lengths are observed. At a more attractive surface, a sticky surface layer is built up, giving rise to small slip lengths. Upon cooling, delta decreases at high temperatures, passes through a minimum, and grows for T-->Tg. At strongly attractive surfaces, the Navier-slip condition fails to describe Couette and Poiseuille flows simultaneously. The simulations are corroborated by a schematic, two-layer model suggesting that the observations do not depend on details of the computational model.

  10. Length Matters: Informational Load in Ambiguity Resolution

    Directory of Open Access Journals (Sweden)

    Barbara Hemforth

    2013-07-01

    Full Text Available In this paper, we will compare prosodic and pragmatic approaches to the role of constituent length in attachment ambiguities. Lengthening a constituent affects its informativity: longer constituents are usually less predictable (Levy & Florian, 2007 and demand a higher processing load than shorter ones (Almor, 1999. Following neo-Gricean accounts (Levinson, 1987 and 1991, increased informational load needs to be justified. This justification is achieved more easily when the long constituent conveys new information and when it relates to central elements of the utterance. Informational load is, however, not a simple question of length in numbers of characters or syllables but more likely a question of amount of information. In three off-line experiments using a cloze task, we will compare the effect of lengthening ambiguous prepositional phrases as in [1a/b/c] either by lengthening a city name or by adding information about the city. We will show that only lengthening by adding information increases attachment to a more central element of the utterance. These results will be discussed based on prosodic and pragmatic factors explaining the role of constituent length for attachment ambiguities.[1] Peter met the doctor of the lawyer from a. Apt. / b. Aix-en-Provence / c. the beautiful city of Apt.Dans cet article, nous comparons une approche prosodique avec une approche pragmatique pour rendre compte des effets de la longueur des constituants dans les ambigüités d’attachement. Augmenter la longueur d’un constituant a des conséquences sur l’information qu’il véhicule : plus un constituant est long et moins il est prédictible (Levy et Florian, 2007 et plus son coût de traitement augmente (Almor, 1999. Suivant les principes néo-gricéens (Levinson, 1987 et 1991, augmenter le poids informationnel doit être justifié. Cette justification est plus facilement satisfaite lorsqu’un constituant long véhicule une information

  11. Hard rectangles near curved hard walls: tuning the sign of the Tolman length

    CERN Document Server

    Sitta, Christoph E; Wittkowski, Raphael; Löwen, Hartmut

    2016-01-01

    Combining analytic calculations, computer simulations, and classical density functional theory we determine the interfacial tension of orientable two-dimensional hard rectangles near a curved hard wall. Both a circular cavity holding the particles and a hard circular obstacle surrounded by particles are considered. We focus on moderate bulk densities (corresponding to area fractions up to 50 percent) where the bulk phase is isotropic and vary the aspect ratio of the rectangles and the curvature of the wall. The Tolman length, which gives the leading curvature correction of the interfacial tension, is found to change sign at a finite density, which can be tuned via the aspect ratio of the rectangles.

  12. Effect of healthy lifestyle behaviors on the association between leukocyte telomere length and coronary artery calcium.

    Science.gov (United States)

    Diaz, Vanessa A; Mainous, Arch G; Everett, Charles J; Schoepf, U Joseph; Codd, Veryan; Samani, Nilesh J; Samanii, Nilesh J

    2010-09-01

    The telomere length is an indicator of biologic aging, and shorter telomeres have been associated with coronary artery calcium (CAC), a validated indicator of coronary atherosclerosis. It is unclear, however, whether healthy lifestyle behaviors affect the relation between telomere length and CAC. In a sample of subjects aged 40 to 64 years with no previous diagnosis of coronary heart disease, stroke, diabetes mellitus, or cancer (n = 318), healthy lifestyle behaviors of greater fruit and vegetable consumption, lower meat consumption, exercise, being at a healthy weight, and the presence of social support were examined to determine whether they attenuated the association between a shorter telomere length and the presence of CAC. Logistic regression analyses controlling for age, gender, race/ethnicity, and Framingham risk score revealed that the relation between having shorter telomeres and the presence of CAC was attenuated in the presence of high social support, low meat consumption, and high fruit and vegetable consumption. Those with shorter telomeres and these characteristics were not significantly different from those with longer telomeres. Conversely, the subjects with shorter telomeres and less healthy lifestyles had a significantly increased risk of the presence of CAC: low fruit and vegetable consumption (odds ratio 3.30, 95% confidence interval 1.61 to 6.75), high meat consumption (odds ratio 3.33, 95% confidence interval 1.54 to 7.20), and low social support (odds ratio 2.58, 95% confidence interval 1.24 to 5.37). Stratification by gender yielded similar results for men; however, among women, only fruit and vegetable consumption attenuated the shorter telomere length and CAC relation. In conclusion, the results of the present study suggest that being involved in healthy lifestyle behaviors might attenuate the association between shorter telomere length and coronary atherosclerosis, as identified using CAC.

  13. A Librarian's Primer on Financial Ratios.

    Science.gov (United States)

    Kerbel, Sandra Sandor

    1982-01-01

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

  14. Identification of cellulosic fibers and determination of their blend ratio using terahertz spectroscopy

    Science.gov (United States)

    Kurabayashi, Toru; Shuhama, Hayato; Yodokawa, Shinichi; Kosaka, Satoru

    2017-01-01

    We demonstrate a method for identifying fabric fibers and their blend ratio using terahertz spectroscopy. The absorption spectra of cellulosic fibers are discriminative due to the types of crystallized cellulose in each type of fiber when the samples are prepared by cutting the fibers to 0.2 mm lengths. The blend ratio of two different fibers was quantified using principal component analysis of the first derivative of the spectra, followed by multiple classification analysis.

  15. Influence of corn silage particle length on the performance of lactating dairy cows fed supplemental tallow.

    Science.gov (United States)

    Onetti, S G; Shaver, R D; Bertics, S J; Grummer, R R

    2003-09-01

    The objective of this study was to determine if the length of chop of processed corn silage influences the impact of supplemental fat on rumen fermentation and performance of dairy cows. We hypothesized that increasing forage particle length may alleviate the interference of fat on rumen fermentation. Sixteen Holstein cows averaging 120 d in milk were used in a replicated 4 x 4 Latin square design with 21-d periods. Treatments were arranged as a 2 x 2 factorial with 0 or 2% tallow (dry matter basis), and corn silage harvested at either 19 or 32 mm theoretical length of cut. The forage:concentrate ratio was 50:50, and diets were formulated to contain 18% crude protein and 32% neutral detergent fiber (dry matter basis). Cows were allowed ad libitum consumption of diets that were fed twice daily as a total mixed ration. Fat supplemented cows had lower dry matter intake and produced less milk fat relative to nonsupplemented cows. No effect of corn silage particle length was observed for dry matter intake and milk fat production. Proportion of trans-10 C18:1 and of trans-10, cis-12 conjugated linoleic acid was highest in milk fat of cows fed 2% supplemental tallow. Rumen pH was not affected by feeding tallow, and tended to be highest for cows eating the 32-mm theoretical length of chop corn silage diets. No effect of treatments was observed for rumen acetate-to-propionate ratio or rumen ammonia concentration. In this study, tallow supplementation had a negative impact on performance of dairy cows regardless of the corn silage particle length. Feeding tallow increased formation of trans-fatty acids in the rumen in the absence of significant changes in the rumen environment.

  16. Telomere length of tumor tissues and survival in patients with early stage non-small cell lung cancer.

    Science.gov (United States)

    Jeon, Hyo-Sung; Choi, Yi Young; Choi, Jin Eun; Lee, Won Kee; Lee, Eungbae; Yoo, Seung Soo; Lee, Shin Yup; Lee, Jaehee; Cha, Seung Ick; Kim, Chang Ho; Park, Jae Yong

    2014-04-01

    Telomere shortening leads to genomic instability that drives oncogenesis through the activation of telomerase and the generation of other mutations necessary for tumor progression. This study was conducted to determine the impact of telomere shortening on the survival of patients with early stage non-small cell lung cancer (NSCLC). Relative telomere length in tumor tissues was measured by quantitative polymerase chain reaction in 164 patients with surgically resected NSCLC. The association between telomere length and overall survival (OS) and disease-free survival (DFS) was analyzed. When the patients were categorized into quartiles based on telomere length, those patients with the 1st quartile (shortest) of telomere length had a significantly worse OS and DFS compared to patients with the 2nd to the 4th quartiles of telomere length (adjusted hazard ratio for OS = 2.67, 95% confidence interval = 1.50-4.75, P = 0.001; and adjusted hazard ratio for DFS = 1.92, 95% confidence interval = 1.17-3.14, P = 0.01). An association between telomere length and survival outcome was more pronounced in squamous cell carcinomas than adenocarcinomas (P-value of test for homogeneity for OS and DFS = 0.05 and 0.02, respectively). Telomere length of tumor tissues is an independent prognostic factor in patients with surgically resected early stage NSCLC.

  17. Determining Extinction Ratio Of A Laser Diode

    Science.gov (United States)

    Unger, Glenn L.

    1992-01-01

    Improved technique to determine extinction ratio of pulsed laser diode based partly on definition of extinction ratio applicable to nonideal laser pulses. Heretofore, determinations involved assumption of ideal laser pulses, and neglected optical power from background light. Because power fluctuates during real pulse, more realistic to define extinction ratio in terms of energy obtained.

  18. Reconstruction of femoral length from fragmentary femora

    Science.gov (United States)

    Offei, Eric Bekoe; Osabutey, Casmiel Kwabena

    2016-01-01

    The reconstruction of femoral length (FL) from fragmentary femora is an essential step in estimating stature from fragmentary skeletal remains in forensic investigations. While regression formulae for doing this have been suggested for several populations, such formulae have not been established for Ghanaian skeletal remains. This study, therefore, seeks to derive regression formulae for reconstruction of FL from fragmentary femora of skeletal samples obtained from Ghana. Six measurements (vertical head diameter, transverse head diameter, bicondylar breadth, epicondylar breadth, sub-trochanteric anterior-posterior diameter, and sub-trochanteric transverse diameter) were acquired from different anatomical portions of the femur and the relationship between each acquired measurement and FL was analyzed using linear regression. The results indicated significantly moderate-to-high correlations (r=0.580–0.818) between FL and each acquired measurement. The error estimates of the regression formulae were relatively low (i.e., standard error of estimate, 13.66–19.28 mm), suggesting that the discrepancies between actual and estimated stature were relatively low. Compared with other measurements, sub-trochanteric transverse diameter was the best estimate of FL. In the absence of a complete femur, the regression formulae based on the assessed measurements may be used to infer FL, from which stature can be estimated in forensic investigations. PMID:27722014

  19. Correlation length of magnetosheath fluctuations: Cluster statistics

    Directory of Open Access Journals (Sweden)

    O. Gutynska

    2008-09-01

    Full Text Available Magnetosheath parameters are usually described by gasdynamic or magnetohydrodynamic (MHD models but these models cannot account for one of the most important sources of magnetosheath fluctuations – the foreshock. Earlier statistical processing of a large amount of magnetosheath observations has shown that the magnetosheath magnetic field and plasma flow fluctuations downstream of the quasiparallel shock are much larger than those at the opposite flank. These studies were based on the observations of a single spacecraft and thus they could not provide full information on propagation of the fluctuations through the magnetosheath.

    We present the results of a statistical survey of the magnetosheath magnetic field fluctuations using two years of Cluster observations. We discuss the dependence of the cross-correlation coefficients between different spacecraft pairs on the orientation of the separation vector with respect to the average magnetic field and plasma flow vectors and other parameters. We have found that the correlation length does not exceed ~1 RE in the analyzed frequency range (0.001–0.125 Hz and does not depend significantly on the magnetic field or plasma flow direction. A close connection of cross-correlation coefficients computed in the magnetosheath with the cross-correlation coefficients between a solar wind monitor and a magnetosheath spacecraft suggests that solar wind structures persist on the background of magnetosheath fluctuations.

  20. Quantum Minimal Length and Transplanckian Photons

    CERN Document Server

    Lubo, M

    2000-01-01

    In this paper we first give arguments supporting the idea that a B.T.Z black hole can face a transplankian problem even when its mass is small. K.M.M quantum theory is applied to the Hawking evaporation of the Schwarzchild and B.T.Z black holes. Working in the physically safe quasi position representation, we argue that the oscillating term present in a previous analysis is removed so that actually one doesn't need an average procedure. We expand the s wave function as the exponential of a series in the minimal length of the new quantum theory. This reduces an infinite order differential equation to a numerable set of finite order ones. We obtain the striking result that the infinity of arbitrary constants induced by the order of the wave equation has no physical meaning due to normalization. We finally construct gaussian wave pacqets and study their trajectories. We suggest a quantitative description of the non locality zone and its dependance on the K.M.M energy scale. Potential incidences on unitarity are ...

  1. Length-Limited Data Transformation and Compression

    Energy Technology Data Exchange (ETDEWEB)

    Senecal, Joshua G. [Univ. of California, Davis, CA (United States)

    2005-09-01

    Scientific computation is used for the simulation of increasingly complex phenomena, and generates data sets of ever increasing size, often on the order of terabytes. All of this data creates difficulties. Several problems that have been identified are (1) the inability to effectively handle the massive amounts of data created, (2) the inability to get the data off the computer and into storage fast enough, and (3) the inability of a remote user to easily obtain a rendered image of the data resulting from a simulation run. This dissertation presents several techniques that were developed to address these issues. The first is a prototype bin coder based on variable-to-variable length codes. The codes utilized are created through a process of parse tree leaf merging, rather than the common practice of leaf extension. This coder is very fast and its compression efficiency is comparable to other state-of-the-art coders. The second contribution is the Piecewise-Linear Haar (PLHaar) transform, a reversible n-bit to n-bit wavelet-like transform. PLHaar is simple to implement, ideal for environments where transform coefficients must be kept the same size as the original data, and is the only n-bit to n-bit transform suitable for both lossy and lossless coding.

  2. Optimal Length Scale for a Turbulent Dynamo.

    Science.gov (United States)

    Sadek, Mira; Alexakis, Alexandros; Fauve, Stephan

    2016-02-19

    We demonstrate that there is an optimal forcing length scale for low Prandtl number dynamo flows that can significantly reduce the required energy injection rate. The investigation is based on simulations of the induction equation in a periodic box of size 2πL. The flows considered are the laminar and turbulent ABC flows forced at different forcing wave numbers k_{f}, where the turbulent case is simulated using a subgrid turbulence model. At the smallest allowed forcing wave number k_{f}=k_{min}=1/L the laminar critical magnetic Reynolds number Rm_{c}^{lam} is more than an order of magnitude smaller than the turbulent critical magnetic Reynolds number Rm_{c}^{turb} due to the hindering effect of turbulent fluctuations. We show that this hindering effect is almost suppressed when the forcing wave number k_{f} is increased above an optimum wave number k_{f}L≃4 for which Rm_{c}^{turb} is minimum. At this optimal wave number, Rm_{c}^{turb} is smaller by more than a factor of 10 than the case forced in k_{f}=1. This leads to a reduction of the energy injection rate by 3 orders of magnitude when compared to the case where the system is forced at the largest scales and thus provides a new strategy for the design of a fully turbulent experimental dynamo.

  3. Inflation with a stringy minimal length, reworked

    CERN Document Server

    Palma, Gonzalo A

    2009-01-01

    In this paper we revisit the formulation of scalar field theories on de Sitter backgrounds subject to the generalized uncertainty principle (GUP). The GUP arises in several contexts in string theory, but is most readily thought of as resulting from using strings as effective probes of geometry, which suggests an uncertainty relation incorporating the string scale $l_s$. After reviewing the string theoretic case for the GUP, which implies a minimum length scale $l_s$, we follow in the footsteps of Kempf and concern ourselves as to how one might write down field theories which respect the GUP. We uncover a new representation of the GUP, which unlike previous studies, readily permits analytical solutions for the mode functions of a scalar field on de Sitter backgrounds. We find that scalar fields cannot be quantized on inflationary backgrounds with a Hubble radius $H^{-1}$ smaller than the string scale, implying a potential sub-planckian cutoff on the scale of inflation resulting from the GUP. We also compute or...

  4. Length-Limited Data Transformation and Compression

    Energy Technology Data Exchange (ETDEWEB)

    Senecal, J G

    2005-05-17

    Scientific computation is used for the simulation of increasingly complex phenomena, and generates data sets of ever increasing size, often on the order of terabytes. All of this data creates difficulties. Several problems that have been identified are (1) the inability to effectively handle the massive amounts of data created, (2) the inability to get the data off the computer and into storage fast enough, and (3) the inability of a remote user to easily obtain a rendered image of the data resulting from a simulation run. This dissertation presents several techniques that were developed to address these issues. The first is a prototype bin coder based on variable-to-variable length codes. The codes utilized are created through a process of parse tree leaf merging, rather than the common practice of leaf extension. This coder is very fast and its compression efficiency is comparable to other state-of-the-art coders. The second contribution is the Piecewise-Linear Haar (PLHaar) transform, a reversible n-bit to n-bit wavelet-like transform. PLHaar is simple to implement, ideal for environments where transform coefficients must be kept the same size as the original data, and is the only n-bit to n-bit transform suitable for both lossy and lossless coding.

  5. First Russian long length HTS power cable

    Science.gov (United States)

    Volkov, Eduard P.; Vysotsky, Vitaly S.; Firsov, Valery P.

    2012-11-01

    The Russian R&D Program for superconducting power devices is underway, supported both by government and electric power companies. In this program R&D on HTS power cables is considered as most advanced and close to commercialization. In the framework of the program, several, heavily instrumented, 5 m cables have been tested following by the 30 m - 3 phase experimental power cable development and testing in 2008-2009. The latest achievement is development and testing of the first long length 3 × 200 m power cable with rating 1.5/2 kA-20 kV. In parallel with just the cable development the innovative cryogenic system has been developed as well for the cable cooling. The system is using neon as working substance and radial turbo-machines in refrigerator. Cooling power is up to ∼8 kW at 65 K, inter-maintenance time ∼30,000 h. The cryogenic pump with superconducting motor can be used to provide subcooled liquid nitrogen flow ∼0.1-1.5 kg/s at 0.1-2.5 MPa pressure. After extensive tests at special test facility, HTS power cable and cryogenic system are planning to be installed at some substation in Moscow utility grid. In this review some details about Russian HTS power application program, 200 m cable and cryogenic system designs and tests results are presented.

  6. Debye screening length effects of nanostructured materials

    CERN Document Server

    Ghatak, Kamakhya Prasad

    2014-01-01

    This monograph solely investigates the Debye Screening Length (DSL) in semiconductors and their nano-structures. The materials considered are quantized structures of non-linear optical, III-V, II-VI, Ge, Te, Platinum Antimonide, stressed materials, Bismuth, GaP, Gallium Antimonide, II-V and Bismuth Telluride respectively. The DSL in opto-electronic materials and their quantum confined counterparts is studied in the presence of strong light waves and intense electric fields on the basis of newly formulated electron dispersion laws that control the studies of such quantum effect devices. The suggestions for the experimental determination of 2D and 3D DSL and the importance of measurement of band gap in optoelectronic materials under intense built-in electric field in nano devices and strong external photo excitation (for measuring photon induced physical properties) have also been discussed in this context. The influence of crossed electric and quantizing magnetic fields on the DSL and the DSL in heavily doped ...

  7. Validation of Navigation Ultrasound for Clavicular Length Measurement

    DEFF Research Database (Denmark)

    Høj, Anders Thorsmark; Villa, Chiara; Christensen, Ole M

    2017-01-01

    Accurate clavicular length measurement is considered important for the selection of patients requiring surgical treatment after a midclavicular fracture. As radiographic length measurements can be inaccurate to varying degrees, new measurement methods are needed. Use of novel technology, navigati...

  8. Lake Basin Fetch and Maximum Length/Width

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

  9. Electrophoresis of semiflexible heteropolymers and the ``hydrodynamic Kuhn length''

    Science.gov (United States)

    Chubynsky, Mykyta V.; Slater, Gary W.

    Semiflexible polymers, such as DNA, are rodlike for short lengths and coil-like for long lengths. For purely geometric properties, such as the end-to-end distance, the crossover between these two behaviors occurs when the polymer length is on the order of the Kuhn length. On the other hand, for the hydrodynamic friction coefficient it is easy to see by comparing the expressions for a rod and a coil that the crossover should occur at the polymer length, termed by us the hydrodynamic Kuhn length, which is larger than the ordinary Kuhn length by a logarithmic factor that can be quite significant. We show that for the problem of electrophoresis of a heteropolymer consisting of several blocks of (in general) different stiffnesses, both of these length scales can be important depending on the details of the problem.

  10. Cervical Length: Why Does It Matter during Pregnancy?

    Science.gov (United States)

    Healthy Lifestyle Pregnancy week by week During pregnancy, what's the significance of cervical length? Answers from Shannon K. Laughlin-Tommaso, ... 2015 Original article: http://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/cervical-length/faq- ...

  11. Effect of stride length on overarm throwing delivery: Part II: An angular momentum response.

    Science.gov (United States)

    Ramsey, Dan K; Crotin, Ryan L

    2016-04-01

    This is the second component of a two-part series investigating 3D momentum profiles specific to overhand throwing, where altering stride reportedly influences throwing mechanics resulting in significantly different physiologic outcomes and linear momentum profiles. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired stride length. An 8-camera motion capture system (240Hz) integrated with two force plates (960Hz) and radar gun tracked each overhand throw. Segmental angular momentums were summed yielding throwing arm and total body momentums, from which compensation ratio's (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different angular momentum profiles, in particular total body, throwing arm, and momentum compensation ratios (P⩽0.05) as a result of manipulating stride length. Sagittal, frontal, and transverse angular momentums were affected by stride length changes. Transverse magnitudes showed greatest effects for total body, throwing arm, and momentum compensation ratios. Since the trunk is the main contributor to linear and angular momentum, longer strides appear to better regulate transverse trunk momentum in double support, whereas shorter strides show increased momentum prior to throwing arm acceleration.

  12. Impact of Dehydroepiandrosterone Sulfate on Newborn Leukocyte Telomere Length

    Science.gov (United States)

    Liu, Han; Zhou, Guangdi; Chen, Qian; Ouyang, Fengxiu; Little, Julian; Zhang, Jun; Chen, Dan

    2017-01-01

    The newborn setting of leukocyte telomere length (LTL) likely has important implications for telomere dynamics over the lifespan. However, its determinants are poorly understood. Hormones play an important role during pregnancy and delivery. We hypothesized that exposure to hormones may impact the fetal telomere biology system. To test this hypothesis, cortisol, estradiol, dehydroepiandrosterone sulfate (DHEAS) and reactive oxygen species (ROS) were measured in cord blood of 821 newborns from a prospective study. After accounting for the effects of potential determinants of newborn LTL, a 10-fold increase in DHEAS concentration was associated with a 0.021 increase in T/S ratio of newborn LTL (95% confidence interval: 0.009–0.034, P = 0.0008). For newborns who fell in the lowest quartile of DHEAS level, the mean newborn LTL was estimated to be approximately 2.0% shorter than the newborns in the highest DHEAS concentration quartile (P = 0.0014). However, no association was found between newborn LTL and cortisol or estradiol. As expected, newborns with higher ROS level (ROS > 260 mol/L) had lower LTL compared to that with lower ROS level (ROS ≤ 260 mol/L) (P = 0.007). There was also an inverse relationship between DHEAS and ROS (P programming” effect on the newborn telomere biology system. PMID:28186106

  13. Critical Lengths of Error Events in Convolutional Codes

    DEFF Research Database (Denmark)

    Justesen, Jørn; Andersen, Jakob Dahl

    1998-01-01

    If the calculation of the critical length is based on the expurgated exponent, the length becomes nonzero for low error probabilities. This result applies to typical long codes, but it may also be useful for modeling error events in specific codes......If the calculation of the critical length is based on the expurgated exponent, the length becomes nonzero for low error probabilities. This result applies to typical long codes, but it may also be useful for modeling error events in specific codes...

  14. The use of digit ratios as markers for perinatal androgen action

    Directory of Open Access Journals (Sweden)

    McIntyre Matthew H

    2006-02-01

    Full Text Available Abstract Since the ratio of the second-to-fourth finger length was first proposed as a marker for prenatal androgen action in 1998, over 100 studies have been published that have either further tested the association between the digit ratio and prenatal androgens, or employed digit ratios as a marker to investigate the association between prenatal androgens and a variety of outcomes, including behavior, fertility, and disease risks. Despite the clear demand for an adult marker of prenatal androgen action and increased use of digit ratios as such a marker, its validity remains controversial. This review (1 evaluates current evidence for the relationship between digit ratios and prenatal androgens (using experimentation with animal models, amniotic testosterone, and congenital adrenal hyperplasia case-control studies, (2 describes opportunities for future validation tests, and (3 compares the potential advantages and disadvantages of digit ratio measures with more established methods for studying the effects of prenatal androgens.

  15. Heritability of telomere length in the Zebra Finch

    NARCIS (Netherlands)

    Atema, Els; Mulder, Ellis; Dugdale, Hannah L.; Briga, Michael; van Noordwijk, Arie J.; Verhulst, Simon

    2015-01-01

    Telomere length predicts survival in birds, and many stressors that presumably reduce fitness have also been linked to telomere length. The response to selection of telomere length will be largely determined by the heritability of this trait; however, little is known about the genetic component of t

  16. Advantages and risks in increasing cyclone separator length

    NARCIS (Netherlands)

    Hoffmann, AC; de Groot, M; Peng, W; Dries, HWA; Kater, J

    2001-01-01

    The effect of cyclone length on separation efficiency and pressure drop has been investigated experimentally and theoretically by varying the length of the cylindrical segment of a cylinder-on-cone cyclone. Experimental results based on cyclone lengths from 2.65 to 6.15 cyclone diameters showed a ma

  17. Path-length-resolved optical Doppler perfusion monitoring

    NARCIS (Netherlands)

    Varghese, Babu; Rajan, Vinayakrishnan; Leeuwen, van Ton G.; Steenbergen, Wiendelt

    2007-01-01

    We report the first path-length-resolved perfusion measurements on human skin measured with a phase-modulated low-coherence Mach-Zehnder interferometer with spatially separated fibers for illumination and detection. Optical path lengths of Doppler shifted and unshifted light and path-length-dependen

  18. Application of Performance Ratios in Portfolio Optimization

    Directory of Open Access Journals (Sweden)

    Aleš Kresta

    2015-01-01

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

  19. Spectral ratio method for measuring emissivity

    Science.gov (United States)

    Watson, K.

    1992-01-01

    The spectral ratio method is based on the concept that although the spectral radiances are very sensitive to small changes in temperature the ratios are not. Only an approximate estimate of temperature is required thus, for example, we can determine the emissivity ratio to an accuracy of 1% with a temperature estimate that is only accurate to 12.5 K. Selecting the maximum value of the channel brightness temperatures is an unbiased estimate. Laboratory and field spectral data are easily converted into spectral ratio plots. The ratio method is limited by system signal:noise and spectral band-width. The images can appear quite noisy because ratios enhance high frequencies and may require spatial filtering. Atmospheric effects tend to rescale the ratios and require using an atmospheric model or a calibration site. ?? 1992.

  20. Leg Length Versus Torso Length in Pedophilia: Further Evidence of Atypical Physical Development Early in Life.

    Science.gov (United States)

    Fazio, Rachel L; Dyshniku, Fiona; Lykins, Amy D; Cantor, James M

    2015-10-12

    Adult men's height results from an interaction among positive and negative influences, including genetic predisposition, conditions in utero, and influences during early development such as nutritional quality, pathogen exposure, and socioeconomic status. Decreased height, reflected specifically as a decreased leg length, is strongly associated with increased risk of poorer health outcomes. Although prior research has repeatedly shown that pedophiles are shorter than nonpedophiles, the largest study to date relied on self-reported height. In the present study, pedophiles demonstrated reduced measured height and reduced leg length as compared with teleiophiles. Given the prenatal and early childhood origins of height, these findings contribute additional evidence to a biological, developmental origin of pedophilia. In addition, the magnitude of this height difference was substantially larger than that found in children exposed to a variety of early environmental stressors, but similar to that seen in other biologically based neurodevelopmental disorders.

  1. Leg length discrepancy in scoliotic patients.

    Science.gov (United States)

    D'Amico, Moreno; Roncoletta, Piero; Di Felice, Francesca; Porto, Daniele; Bellomo, Rosagrazia; Saggini, Raoul

    2012-01-01

    The aetiological aspects as well as postural attitude implications represent an open question in scoliosis evaluation and treatment. Leg length discrepancy (LLD) is often recognised in scoliotic patients, but surprisingly still controversial is the use of underfoot wedge corrections in order to compensate pelvis tilt. In fact, literature reports conflicting results on the efficacy of LLD equalization also given the argued uncertainty of LLD clinical assessment and limitations related to X-ray measurements. Moreover concern is about anatomic and functional LLD and associated estimation of the pelvic torsion. In such a topic, a significant helpful tool has been demonstrated to be 3D kinematic optoelectronic measurements and other useful data obtained from force platforms and/or baropodographic systems. 135 (94.4%) out of 143 Scoliotic patients sample (av. age 16.4±10.2 Y range 4-66 Y), have been found to improve posture when LLD was corrected. The 143 patients showed a mean lower limb discrepancy of μ=10.2±5.2mm associated to a mean main scoliotic curve μ=16.4°±9.4° Cobb (frontal plane), mean Spinal offset μ=7.5±5.5mm and mean Global offset μ=10.1±7.1mm. The applied paired t-test comparison (indifferent vs. corrected orthostasis) showed significant (p < 0.05) postural improvements could be obtained in the whole or in a part of the considered postural parameters, after the application of suitable under-foot wedge. The present investigation confirm results of a previous study demonstrating the efficacy of under-foot wedge use in leg asymmetry correction, posture re-balancing and spine deformities reduction, pointing out the significant contribution of the 3D opto-electronic measurement approach in the critical process of assessing the correct under-foot wedge size, therapy planning and monitoring.

  2. Leukocyte telomere length and hippocampus volume: a meta-analysis [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Gustav Nilsonne

    2015-10-01

    Full Text Available Leukocyte telomere length has been shown to correlate to hippocampus volume, but effect estimates differ in magnitude and are not uniformly positive. This study aimed primarily to investigate the relationship between leukocyte telomere length and hippocampus gray matter volume by meta-analysis and secondarily to investigate possible effect moderators. Five studies were included with a total of 2107 participants, of which 1960 were contributed by one single influential study. A random-effects meta-analysis estimated the effect to r = 0.12 [95% CI -0.13, 0.37] in the presence of heterogeneity and a subjectively estimated moderate to high risk of bias. There was no evidence that apolipoprotein E (APOE genotype was an effect moderator, nor that the ratio of leukocyte telomerase activity to telomere length was a better predictor than leukocyte telomere length for hippocampus volume. This meta-analysis, while not proving a positive relationship, also is not able to disprove the earlier finding of a positive correlation in the one large study included in analyses. We propose that a relationship between leukocyte telomere length and hippocamus volume may be mediated by transmigrating monocytes which differentiate into microglia in the brain parenchyma.

  3. RELATIONSHIP BETWEEN INTERNAL ANAL SPHINCTER FUNCTION AND LENGTH OF REMAINING RECTUM AFTER RESECTING RECTAL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    Xiao Xiaowei

    1998-01-01

    Objective: To study the relationship between internal anal sphincter function and length of remaining rectum after resecting rectal carcinoma. Methods: Preoperatively,21 patients were evaluated via patients' clinical date,including anal resting pressure (resting pressure) assay.Six months postoperatively, repeated manometric studies and clinical evaluations were performed to assess the level of continence. The formula use for calculating postoperative resting pressure is as follows: postoperative resting pressure=0.42×preoperative resting pressure+1.56×length of remaining recturm+12.37 (R2=0.58; P<0.01).Degree of continence was graded based on severity of the dysfunction and grade of the continence score. Results:It was demonstrated the patients with low postoperative resting pressures (<4.0 Kpa) had incontinence, and those with high postoperative resting pressures (>4.7 Kpa) were continent. There were significant correlations between length of the remaining rectum and ratio of the decrease in maximum resting pressure (postoperative/preoperative maximum resting pressure; r=0.62; P<0.01). Conclusion:Continence of rectum is influenced by maximum resting pressure of function of the internal anal sphincter, length of remaining rectum is shorter, the more damage to the internal anal sphincter. It is able to foretell stool incontinence by using the postoperative resting pressure formula, and to determine the length of the remaining rectum.

  4. MEASUREMENT OF CERVICAL LENGTH BY VAGINAL SONOGRAPHY: PREDICTION OF PRETERM LABOR

    Directory of Open Access Journals (Sweden)

    F MEHRABIAN

    2001-12-01

    Full Text Available Introduction: Preterm delivery remains a major source of perinatal morbidity and mortality. The patient at risk for preterm delivery could be identified before the onset of uterine activity. Cervical shortening associates with increased risk of preterm delivery. Vaginal ultrasound for measurement of the cervical length can contribute to the prediction, diagnosis and management of preterm delivery. Methods: 780 women attending the antenatal clinic of the Shahid Beheshti and Alzahra hospitals (January 1997 - February 1998 were selected. They had no complications. pregnant with gestational ages between 28-30 weeks were recruited in to the study. Cervical length was recorded by vaginal sonography. They followed up to delivery time. Results: The mean cervical length of the term and preterm groups were statisticaly significantly different. The likelihood ratios of cervical length at various cutoff points were calculated. The appropriate cutoff point based on the receiver operating characteristic curve (35mm was associated with a significant increased likelihood of preterm delivery. Discussion: A single transvaginal sonographic measure of cervical length at 28-30 weeks gestational age can be used to predict the risk of preterm delivery using a cutoff point on 35mm.

  5. Experimental Study of Fiber Length and Orientation in Injection Molded Natural Fiber/Starch Acetate Composites

    Directory of Open Access Journals (Sweden)

    Heidi Peltola

    2011-01-01

    Full Text Available Composite compounds based on triethyl citrate plasticized starch acetate and hemp and flax fibers were prepared by melt processing. Plasticizer contents from 20 to 35 wt% and fiber contents of 10 and 40 wt% were used. The compounded composites were injection molded to tensile test specimens. The effect of processing, melt viscosity and fiber type on the fiber length was investigated. The lengths of fully processed fibers were determined by dissolving the matrix and measuring the length of the remaining fibers by microscope analysis. A clear reductive effect of the processing on the fiber length was noticed. A reduction of fiber length along the increasing fiber content and the decreasing plasticizer content was also detected. This reduction originated from the increasing shear forces during compounding, which again depended on the increased viscosity of the material. Hemp fibers were shown to remain longer and fibrillate more than flax fibers, leading to higher aspect ratio. Thus, the reinforcement efficiency of hemp fibers by the processing was improved, in contrast with flax fibers. In addition, the analysis of fiber dispersion and orientation showed a good dispersion of fibers in the matrix, and a predominant orientation of the fibers in the melt flow direction.

  6. Variable length adjacent partitioning for PTS based PAPR reduction of OFDM signal

    Energy Technology Data Exchange (ETDEWEB)

    Ibraheem, Zeyid T.; Rahman, Md. Mijanur; Yaakob, S. N.; Razalli, Mohammad Shahrazel; Kadhim, Rasim A. [School of Computer and Communication Engineering, Universiti Malaysia Perlis, 02600 Arau, Perlis (Malaysia)

    2015-05-15

    Peak-to-Average power ratio (PAPR) is a major drawback in OFDM communication. It leads the power amplifier into nonlinear region operation resulting into loss of data integrity. As such, there is a strong motivation to find techniques to reduce PAPR. Partial Transmit Sequence (PTS) is an attractive scheme for this purpose. Judicious partitioning the OFDM data frame into disjoint subsets is a pivotal component of any PTS scheme. Out of the existing partitioning techniques, adjacent partitioning is characterized by an attractive trade-off between cost and performance. With an aim of determining effects of length variability of adjacent partitions, we performed an investigation into the performances of a variable length adjacent partitioning (VL-AP) and fixed length adjacent partitioning in comparison with other partitioning schemes such as pseudorandom partitioning. Simulation results with different modulation and partitioning scenarios showed that fixed length adjacent partition had better performance compared to variable length adjacent partitioning. As expected, simulation results showed a slightly better performance of pseudorandom partitioning technique compared to fixed and variable adjacent partitioning schemes. However, as the pseudorandom technique incurs high computational complexities, adjacent partitioning schemes were still seen as favorable candidates for PAPR reduction.

  7. Short telomere length and breast cancer risk: a study in sister sets.

    Science.gov (United States)

    Shen, Jing; Terry, Mary Beth; Gurvich, Irina; Liao, Yuyan; Senie, Ruby T; Santella, Regina M

    2007-06-01

    Telomeres consist of a tandem repeats of the sequence TTAGGG at the ends of chromosomes and play a key role in the maintenance of chromosomal stability. Previous studies indicated that short telomeres are associated with increased risk for human bladder, head and neck, lung, and renal cell cancer. We investigated the association between white blood cell telomere length and breast cancer risk among 268 family sets (287 breast cancer cases and 350 sister controls). Telomere length was assessed by quantitative PCR. The mean telomere length was shorter in cases (mean, 0.70; range, 0.03-1.95) than in unaffected control sisters (mean, 0.74; range, 0.03-2.29), but no significant difference was observed (P = 0.11). When subjects were categorized according to the median telomere length in controls (0.70), affected sisters had shorter telomeres compared with unaffected sisters after adjusting for age at blood donation and smoking status [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.9-1.8], but the association was not statistically significant. The association by quartile of telomere length (Q4 shortest versus Q1 longest) also supported an increase in risk from shorter telomere length, although the association was not statistically significant (OR, 1.6; 95% CI, 0.9-2.7). This association was more pronounced among premenopausal women (OR, 2.1; 95% CI, 0.8-5.5) than postmenopausal women (OR, 1.3; 95% CI, 0.5-3.6 for Q4 versus Q1). If these associations are replicated in larger studies, they provide modest epidemiologic evidence that shortened telomere length may be associated with breast cancer risk.

  8. The association between metacarpal ratio, radiographic hand and knee osteoarthritis and its progression after meniscectomy

    DEFF Research Database (Denmark)

    Paradowski, P T; Lohmander, Stefan; Englund, Martin Kristian

    2013-01-01

    OBJECTIVE: To examine whether the ratio of the second and fourth metacarpal bone length (MC2:MC4) in subjects with prior meniscectomy of the knee is associated with radiographic hand and knee osteoarthritis (OA) and its progression. DESIGN: We assessed 219 subjects (175 men and 44 women) twice...

  9. On the electron to proton mass ratio and the proton structure

    DEFF Research Database (Denmark)

    Trinhammer, Ole L.

    2013-01-01

    We derive an expression for the electron to nucleon mass ratio from a reinterpreted lattice gauge theory Hamiltonian to describe interior baryon dynamics. We use the classical electron radius as our fundamental length scale. Based on expansions on trigonometric Slater determinants for a neutral s...... and d valence quarks of the proton....

  10. Lee-side flow structures of very low aspect ratio cruciform wing–body configurations

    CSIR Research Space (South Africa)

    Tuling, S

    2013-12-01

    Full Text Available of order 0.025 with taper ratio ˜1 with a length of 11.25D mounted on a 19D tangent ogive body. The numerical simulations were performed using Fluent with the Spalart–Allmaras turbulence model. The Mach numbers simulated were 2.0, 2.5, and 3.0 up to angles...

  11. Stable isotope ratios in hair and teeth reflect biologic rhythms.

    Directory of Open Access Journals (Sweden)

    Otto Appenzeller

    Full Text Available Biologic rhythms give insight into normal physiology and disease. They can be used as biomarkers for neuronal degenerations. We present a diverse data set to show that hair and teeth contain an extended record of biologic rhythms, and that analysis of these tissues could yield signals of neurodegenerations. We examined hair from mummified humans from South America, extinct mammals and modern animals and people, both healthy and diseased, and teeth of hominins. We also monitored heart-rate variability, a measure of a biologic rhythm, in some living subjects and analyzed it using power spectra. The samples were examined to determine variations in stable isotope ratios along the length of the hair and across growth-lines of the enamel in teeth. We found recurring circa-annual periods of slow and fast rhythms in hydrogen isotope ratios in hair and carbon and oxygen isotope ratios in teeth. The power spectra contained slow and fast frequency power, matching, in terms of normalized frequency, the spectra of heart rate variability found in our living subjects. Analysis of the power spectra of hydrogen isotope ratios in hair from a patient with neurodegeneration revealed the same spectral features seen in the patient's heart-rate variability. Our study shows that spectral analysis of stable isotope ratios in readily available tissues such as hair could become a powerful diagnostic tool when effective treatments and neuroprotective drugs for neurodegenerative diseases become available. It also suggests that similar analyses of archaeological specimens could give insight into the physiology of ancient people and animals.

  12. Building effectiveness communication ratios for improved building life cycle management

    Energy Technology Data Exchange (ETDEWEB)

    Morrissey, E.; Keane, M.; McCarthy, J. [Ireland National Univ., Cork (Ireland). IRUSE; O' Donnell, J. [Lawrence Berkely National Laboratory, Berkeley, CA (United States)]|[Ireland National Univ., Cork (Ireland). IRUSE

    2005-07-01

    The construction and operation of buildings consumes 35 per cent of total U.S. energy production. Although the application of building energy simulation models in early design stages can significantly increase performance throughout the building life cycle, energy simulation modeling has not been widely adopted by the design community. The complexity and length of time needed to prepare energy models are considered to be barriers, as well as the lack of energy appraisal tools capable of modeling a wide spectrum of hybrid heating, ventilation and air conditioning (HVAC) systems. A performance-based strategy using building effectiveness communication ratios stored in Building Information Models (BIM) was presented in this paper. The strategy aimed to link currently fragmented stages within the building life cycle. It was suggested that the ability to share and exchange information will reduce the amount of user time required for building simulation models. The proposed Building Energy Monitoring Analyzing and Communication (BEMAC) framework is an integrated environment that allows users to share data with other applications through an integrated data model. The data models allow each participant to employ tools specific to their needs without compromising or corrupting project data. Data values elicited from the model act as best-possible values. It was anticipated that by assigning spaces within the simulation model with proposed HVAC systems, reproductions of the energy use by these mechanical systems can contribute to overall energy data representation and analysis. Idealized Effectiveness Ratios and Performance Effectiveness Ratios were discussed in relation to a case study of the Glucksman Art Gallery at the National University of Ireland. Results indicated that the Idealized Effectiveness Ratio is applicable across the entire building life cycle, while the Performance Effectiveness Ratio allows facility managers to investigate the energy saving potential of the

  13. Memory for tonal pitches: a music-length effect hypothesis.

    Science.gov (United States)

    Akiva-Kabiri, Lilach; Vecchi, Tomaso; Granot, Roni; Basso, Demis; Schön, Daniele

    2009-07-01

    One of the most studied effects of verbal working memory (WM) is the influence of the length of the words that compose the list to be remembered. This work aims to investigate the nature of musical WM by replicating the word length effect in the musical domain. Length and rate of presentation were manipulated in a recognition task of tone sequences. Results showed significant effects for both factors (length and presentation rate) as well as their interaction, suggesting the existence of different strategies (e.g., chunking and rehearsal) for the immediate memory of musical information, depending upon the length of the sequences.

  14. Normative data for uterine size according to age and gravidity and possible role of the classical golden ratio.

    Science.gov (United States)

    Verguts, J; Ameye, L; Bourne, T; Timmerman, D

    2013-12-01

    To document normal measurements (length, width, anteroposterior (AP) diameter) and proportions of the non-pregnant uterus according to age and gravidity. We hypothesized that uterine proportions conform to the classical 'golden ratio' (1.618). This was a retrospective study of ultrasonographic measurements of the length, width and AP diameter of non-pregnant uteri recorded in our database between 1 January 2000 and 31 July 2012. All patients for whom abnormal findings were reported were excluded and only the first set of measurements for each patient was retained for analysis. Loess (local regression) analysis was performed using age and gravidity as explanatory variables. Measurements of 5466 non-pregnant uteri were retrieved for analysis. The mean length was found to increase to 72 mm at the age of 40 and decrease to 42 mm at the age of 80 years. Gravidity was associated with greater uterine length, width and AP diameter. Mean length/width ratio was found to be 1.857 at birth, decreasing to 1.452 at the age of 91 years. At the age of 21 years, the mean ratio was found to be 1.618, i.e. equal to the golden ratio. Increasing gravidity was associated with lower mean length/width ratio. Uterine size in non-pregnant women varies in relation to age and gravidity. Mean length/width ratio conformed to the golden ratio at the age of 21, coinciding with peak fertility. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.

  15. Decomposing the queue length distribution of processor-sharing models into queue lengths of permanent customer queues

    NARCIS (Netherlands)

    Cheung, S.-K.; Berg, H. van den; Boucherie, R.J.

    2005-01-01

    We obtain a decomposition result for the steady state queue length distribution in egalitarian processor-sharing (PS) models. In particular, for multi-class egalitarian PS queues, we show that the marginal queue length distribution for each class equals the queue length distribution of an equivalent

  16. An Experimental Measurement on Laminar Burning Velocities and Markstein Length of Iso-Butane-Air Mixtures at Ambient Conditions

    Directory of Open Access Journals (Sweden)

    Yousif Alaeldeen Altag

    2016-01-01

    Full Text Available In the present work, experimental investigation on laminar combustion of iso-butane-air mixtures was conducted in constant volume explosion vessel. The experiments were conducted at wide range of equivalence ratios ranging between Ф = 0.6 and 1.4 and atmospheric pressure of 0.1 MPa and ambient temperature of 303K. Using spherically expanding flame method, flame parameters including stretched, unstretched flame propagation speeds, laminar burning velocities and Markstein length were calculated. For laminar burning velocities the method of error bars of 95% confidence level was applied. In addition, values of Markstein lengths were measured in wide range of equivalence ratios to study the influence of stretch rate on flame instability and burning velocity. It was found that the stretched flame speed and laminar burning velocities increased with equivalence ratios and the peak value was obtained at equivalence ratio of Ф = 1.1. The Markstein length decreased with the increases in equivalence ratios, which indicates that the diffusion thermal flame instability increased at high equivalence ratios in richer mixture side. However, the total deviations in the laminar burning velocities have discrepancies of 1.2-2.9% for all investigated mixtures.

  17. Verification of relationships between anthropometric variables among ureteral stents recipients and ureteric lengths: a challenge for Vitruvian-da Vinci theory.

    Science.gov (United States)

    Acelam, Philip A

    2015-01-01

    To determine and verify how anthropometric variables correlate to ureteric lengths and how well statistical models approximate the actual ureteric lengths. In this work, 129 charts of endourological patients (71 females and 58 males) were studied retrospectively. Data were gathered from various research centers from North and South America. Continuous data were studied using descriptive statistics. Anthropometric variables (age, body surface area, body weight, obesity, and stature) were utilized as predictors of ureteric lengths. Linear regressions and correlations were used for studying relationships between the predictors and the outcome variables (ureteric lengths); P-value was set at 0.05. To assess how well statistical models were capable of predicting the actual ureteric lengths, percentages (or ratios of matched to mismatched results) were employed. The results of the study show that anthropometric variables do not correlate well to ureteric lengths. Statistical models can partially estimate ureteric lengths. Out of the five anthropometric variables studied, three of them: body frame, stature, and weight, each with a Pvariables: age (R (2)=0.01; P=0.20) and obesity (R (2)=0.03; P=0.06), were found to be poor estimators of ureteric lengths. None of the predictors reached the expected (match:above:below) ratio of 1:0:0 to qualify as reliable predictors of ureteric lengths. There is not sufficient evidence to conclude that anthropometric variables can reliably predict ureteric lengths. These variables appear to lack adequate specificity as they failed to reach the expected (match:above:below) ratio of 1:0:0. Consequently, selections of ureteral stents continue to remain a challenge. However, height (R (2)=0.68) with the (match:above:below) ratio of 3:3:4 appears suited for use as estimator, but on the basis of decision rule. Additional research is recommended for stent improvements and ureteric length determinations.

  18. Network Packet Length Covert Channel Based on Empirical Distribution Function

    Directory of Open Access Journals (Sweden)

    Lihua Zhang

    2014-06-01

    Full Text Available Network packet length covert channel modulates secret message bits onto the packet lengths to transmit secret messages. In this paper, a novel network packet length covert channel is proposed. The proposed scheme is based on the empirical distribution function of packet length series of legitimate traffic. Different from the existing schemes, the lengths of packets which are generated by the covert sender follow the distribution of normal traffic more closely in our scheme. To validate the security of the proposed scheme, the state-of-the-art packet length covert channel detection algorithm is adopted. The experimental results show that the packet length covert channel provides a significant performance improvement in detection resistance meanings

  19. Roughness Length of Water Vapor over Land Surfaces and Its Influence on Latent Heat Flux

    Directory of Open Access Journals (Sweden)

    Sang-Jong Park

    2010-01-01

    Full Text Available Latent heat flux at the surface is largely dependent on the roughness length for water vapor (z0q. The determination of z0q is still uncertain because of its multifaceted characteristics of surface properties, atmospheric conditions and insufficient observations. In this study, observed values from the Fluxes Over Snow Surface II field experiment (FLOSS-II from November 2002 to March 2003 were utilized to estimate z0q over various land surfaces: bare soil, snow, and senescent grass. The present results indicate that the estimated z0q over bare soil is much smaller than the roughness length of momentum (z0m; thus, the ratio z0m/z0q is larger than those of previous studies by a factor of 20 - 150 for the available flow regime of the roughness Reynolds number, Re* > 0.1. On the snow surface, the ratio is comparable to a previous estimation for the rough flow (Re* > 1, but smaller by a factor of 10 - 50 as the flow became smooth (Re* < 1. Using the estimated ratio, an optimal regression equation of z0m/z0q is determined as a function of Re* for each surface type. The present parameterization of the ratio is found to greatly reduce biases of latent heat flux estimation compared with that estimated by the conventional method, suggesting the usefulness of current parameterization for numerical modeling.

  20. Rapid homogeneous endothelialization of high aspect ratio microvascular networks.

    Science.gov (United States)

    Naik, Nisarga; Hanjaya-Putra, Donny; Haller, Carolyn A; Allen, Mark G; Chaikof, Elliot L

    2015-08-01

    Microvascularization of an engineered tissue construct is necessary to ensure the nourishment and viability of the hosted cells. Microvascular constructs can be created by seeding the luminal surfaces of microfluidic channel arrays with endothelial cells. However, in a conventional flow-based system, the uniformity of endothelialization of such an engineered microvascular network is constrained by mass transfer of the cells through high length-to-diameter (L/D) aspect ratio microchannels. Moreover, given the inherent limitations of the initial seeding process to generate a uniform cell coating, the large surface-area-to-volume ratio of microfluidic systems demands long culture periods for the formation of confluent cellular microconduits. In this report, we describe the design of polydimethylsiloxane (PDMS) and poly(glycerol sebacate) (PGS) microvascular constructs with reentrant microchannels that facilitates rapid, spatially homogeneous endothelial cell seeding of a high L/D (2 cm/35 μm; > 550:1) aspect ratio microchannels. MEMS technology was employed for the fabrication of a monolithic, elastomeric, reentrant microvascular construct. Isotropic etching and PDMS micromolding yielded a near-cylindrical microvascular channel array. A 'stretch - seed - seal' operation was implemented for uniform incorporation of endothelial cells along the entire microvascular area of the construct yielding endothelialized microvascular networks in less than 24 h. The feasibility of this endothelialization strategy and the uniformity of cellularization were established using confocal microscope imaging.

  1. Myopia and digit ratio in medical college students.

    Directory of Open Access Journals (Sweden)

    Mathangi Krishnakumar

    Full Text Available Myopia is amongst the most common refractive errors in the world. Both environmental and genetic factors are attributed to its causation, however all factors contributing to the development of myopia is yet to be found. Recent studies show presence of sex hormone receptor in the eyes. This has been shown to have a role in the development of various ocular pathologies. The second to fourth finger length ratio (2D:4D has been hypothesised to be determined by exposure to sex steroids prenatally and thus considered a crude measure for prenatal androgen exposure. Hence this study was initiated to assess the association between myopia and 2D:4D ratio (a proxy marker to prenatal sex steroid exposure among 100 medical college students of either sex and explore the possibility of role of prenatal sex steroids in causation of myopia. This study showed significant negative associations between myopia and digit ratio favouring a probable causal role of sex steroids on eye growth and development of myopia.

  2. Aspect Ratio Effects in the Driven, Flux-Core Spheromak

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, E B; Romero-Talam?s, C A; LoDestro, L L; Wood, R D; McLean, H S

    2009-03-02

    Resistive magneto-hydrodynamic simulations are used to evaluate the effects of the aspect ratio, A (length to radius ratio) in a spheromak driven by coaxial helicity injection. The simulations are benchmarked against the Sustained Spheromak Physics Experiment (SSPX) [R. D. Wood, et al., Nucl. Nucl. Fusion 45, 1582 (2005)]. Amplification of the bias ('gun') poloidal flux is fit well by a linear dependence (insensitive to A) on the ratio of gun current and bias flux above a threshold dependent on A. For low flux amplifications in the simulations the n = 1 mode is coherent and the mean-field geometry looks like a tilted spheromak. Because the mode has relatively large amplitude the field lines are open everywhere, allowing helicity penetration. Strongly-driven helicity injection at A {le} 1.4 in simulations generates reconnection events which open the magnetic field lines; this state is characteristic of SSPX. Near the spheromak tilt-mode limit, A {approx} 1.67 for a cylindrical flux conserver, the tilt approaches 90{sup o}; reconnection events are not generated up to the strongest drives simulated. The time-sequence of these events suggests that they are representative of a chaotic process. Implications for spheromak experiments are discussed.

  3. On the Australian Bank Financial Ratio Analysis

    Institute of Scientific and Technical Information of China (English)

    张丽娜

    2011-01-01

    Financial ratios,despite some criticisms,are still used as a basis to evaluate a firm's performance,to make credit risk assessment decisions and classify firms into bankrupt and non-bankrupt groups.There are a great number of financial ratios which can be used for the evaluation of banks performance.Golin (2001) provides a list of over 80 ratios covering the major categories of capital,asset quality,profitability & efficiency,and liquidity & funding provides.

  4. Application of Performance Ratios in Portfolio Optimization

    OpenAIRE

    Aleš Kresta

    2015-01-01

    The cornerstone of modern portfolio theory was established by pioneer work of Harry Markowitz. Based on his mean-variance framework, Sharpe formulated his well-known Sharpe ratio aiming to measure the performance of mutual funds. The contemporary development in computer’s computational power allowed to apply more complex performance ratios, which take into account also higher moments of return probability distribution. Although these ratios were proposed to help the investors to improve the r...

  5. Postoperative hypoxia and length of intensive care unit stay after cardiac surgery: the underweight paradox?

    Directory of Open Access Journals (Sweden)

    Marco Ranucci

    Full Text Available OBJECTIVE: Cardiac operations with cardiopulmonary bypass can be associated with postoperative lung dysfunction. The present study investigates the incidence of postoperative hypoxia after cardiac surgery, its relationship with the length of intensive care unit stay, and the role of body mass index in determining postoperative hypoxia and intensive care unit length of stay. DESIGN: Single-center, retrospective study. SETTING: University Hospital. Patients. Adult patients (N = 5,023 who underwent cardiac surgery with CPB. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: According to the body mass index, patients were attributed to six classes, and obesity was defined as a body mass index >30. POH was defined as a PaO2/FiO2 ratio <200 at the arrival in the intensive care unit. Postoperative hypoxia was detected in 1,536 patients (30.6%. Obesity was an independent risk factor for postoperative hypoxia (odds ratio 2.4, 95% confidence interval 2.05-2.78, P = 0.001 and postoperative hypoxia was a determinant of intensive care unit length of stay. There is a significant inverse correlation between body mass index and PaO2/FiO2 ratio, with the risk of postoperative hypoxia increasing by 1.7 folds per each incremental body mass index class. The relationship between body mass index and intensive care unit length of stay is U-shaped, with longer intensive care unit stay in underweight patients and moderate-morbid obese patients. CONCLUSIONS: Obese patients are at higher risk for postoperative hypoxia, but this leads to a prolonged intensive care unit stay only for moderate-morbid obese patients. Obese patients are partially protected against the deleterious effects of hemodilution and transfusions. Underweight patients present the "paradox" of a better lung gas exchange but a longer intensive care unit stay. This is probably due to a higher severity of their cardiac disease.

  6. Back Work Ratio of Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Malaver de la Fuente M.

    2010-07-01

    Full Text Available This paper analizes 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 soft ware helps to show the influence of back work ratio or coupling ratio, compressor and turbine in let 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.

  7. A ratio model of perceptual transparency.

    Science.gov (United States)

    Tommasi, M

    1999-12-01

    A ratio model of the achromatic transparency of a phenomenal surface on a bipartite background is proposed. The model asserts that transparency corresponds to the evaluation of the ratio of the lightness difference inside the transparent surface to the difference in reference lightness inside the background. It applies to both balanced and unbalanced transparency. The ratio model was compared experimentally with the previous perceptual model of achromatic transparency proposed by Metelli. Each model was tested by comparing the rated with the predicted transparency. Analysis shows that the ratio model provides better predictions of transparency than those provided by Metelli's model.

  8. Force dynamics in fixed-ratio schedules.

    Science.gov (United States)

    Pinkston, Jonathan W; McBee, Lindsey N

    2014-03-01

    Fixed-ratio schedules are widely used in behavioral research. Although fixed-ratio schedules often conjure up relationships to work and effort, little is known about effort-related measures in these schedules. Early research had shown that force and effort of operant behavior vary systematically during the execution of ratio schedules, and the goal of the present study was to revisit early research on force dynamics in fixed-ratio schedules. Four rats earned sucrose by pressing an isometric force transducer. Presses produced sucrose after ten or twenty responses. In general, the force of responses increased then decreased systematically across the ratio. The possibility that decreases in force during ratio execution was due to a trade-off with the differential reinforcement of short inter-response times (IRT) was investigated in an additional condition where sucrose was made available according to a tandem fixed-ratio 19 inter-response (IRT)> t schedule. The tandem IRT requirement did not eliminate decreasing trends in force across the ratio; unexpectedly, the tandem requirement did eliminate increases in force early in the ratio, which may reflect sequence-level organization operating in the control of force dynamics.

  9. Influence of grid aspect ratio on planetary boundary layer turbulence in large-eddy simulations

    Directory of Open Access Journals (Sweden)

    S. Nishizawa

    2015-10-01

    Full Text Available We examine the influence of the grid aspect ratio of horizontal to vertical grid spacing on turbulence in the planetary boundary layer (PBL in a large-eddy simulation (LES. In order to clarify and distinguish them from other artificial effects caused by numerical schemes, we used a fully compressible meteorological LES model with a fully explicit scheme of temporal integration. The influences are investigated with a series of sensitivity tests with parameter sweeps of spatial resolution and grid aspect ratio. We confirmed that the mixing length of the eddy viscosity and diffusion due to sub-grid-scale turbulence plays an essential role in reproducing the theoretical −5/3 slope of the energy spectrum. If we define the filter length in LES modeling based on consideration of the numerical scheme, and introduce a corrective factor for the grid aspect ratio into the mixing length, the theoretical slope of the energy spectrum can be obtained; otherwise, spurious energy piling appears at high wave numbers. We also found that the grid aspect ratio has influence on the turbulent statistics, especially the skewness of the vertical velocity near the top of the PBL, which becomes spuriously large with large aspect ratio, even if a reasonable spectrum is obtained.

  10. Sex-different response in growth traits to resource heterogeneity explains male-biased sex ratio

    Science.gov (United States)

    Matsushita, Michinari; Takao, Mikako; Makita, Akifumi

    2016-08-01

    In dioecious plants, differences in growth traits between sexes in a response to micro-environmental heterogeneity may affect sex ratio bias and spatial distributions. Here, we examined sex ratios, stem growth traits and spatial distribution patterns in the dioecious clonal shrub Aucuba japonica var. borealis, in stands with varying light intensities. We found that male stems were significantly more decumbent (lower height/length ratio) but female stems were upright (higher height/length ratio). Moreover, we found sex-different response in stem density (no. of stems per unit area) along a light intensity gradient; in males the stem density increased with increases in canopy openness, but not in females. The higher sensitivity of males in increasing stem density to light intensity correlated with male-biased sex ratio; fine-scale sex ratio was strongly male-biased as canopy openness increased. There were also differences between sexes in spatial distributions of stems. Spatial segregation of sexes and male patches occupying larger areas than female patches might result from vigorous growth of males under well-lit environments. In summary, females and males showed different growth responses to environmental variation, and this seemed to be one of possible causes for the sex-differential spatial distributions and locally biased sex ratios.

  11. A polymorphism in the oestrogen receptor gene explains covariance between digit ratio and mating behaviour.

    Science.gov (United States)

    Forstmeier, Wolfgang; Mueller, Jakob C; Kempenaers, Bart

    2010-11-07

    In vertebrates, including humans, the relative length of the second to the fourth digit correlates with sex hormone-dependent behavioural, psychological and physiological traits. However, despite a decade of research, the underlying mechanism linking digit ratio to these sex hormone-dependent traits remains unclear. Previous work suggests that during embryo development, circulating levels of plasma androgens or oestrogens may act through their receptors to affect transcription levels of posterior HOX genes in the developing digits, thereby possibly influencing their relative length. The correlation between digit ratio and sex hormone-dependent traits might thus stem from variation in expression or sensitivity of the sex hormone receptors, or from variation in sex hormone levels in the embryo. Here, we show that in a population of 1156 zebra finches Taeniopygia guttata, a polymorphism in the oestrogen receptor α gene (ESR1) explains 11.3 per cent of the variation in digit ratio, and is also associated with male and female-mating behaviour. By contrast, we found no associations between digit ratio or mating behaviours and polymorphisms in the androgen receptor gene. Thus, our results (i) provide an explanation for the observed significant genetic covariance between digit ratio and male and female mating behaviour and (ii) strongly confirm the indicator function of digit ratio through the oestrogen pathway. Finally, we note that the commonly invoked effect of foetal testosterone on human digit ratio seems to be substantially weaker than the effect described here.

  12. Long Focal Length Large Mirror Fabrication System

    Science.gov (United States)

    Bennett, H. E.

    2003-01-01

    The goals of this ambitious program are (1) to develop systems to make large superpolished optical mirrors, (2) to develop low scatter polishing techniques using centrifugal elutriation, (3) to develop a means of measuring scatter at any point on the mirror, (4) to polish a Hindle sphere to measure the optical figure of a one meter diameter convex mandrel, and (5) to fabricate low scatter, large adaptive optic graphite filled, cyanate ester replica transfer mirrors using these mandrels. Deliverables are a 30 cm diameter superpolished composite AO mirror. We fabricated a 1/3rd meter superpolished zerodur flat mandrel and with the support of our major subcontractor, Composite Mirror Applications Inc (CMA) we have demonstrated a 30 cm lightweight cyanate ester mirror with an rms microroughness between 0.6 and 0.8 nm and 8 faceplate influence function of 5 cm. The influence function was chosen to be comparable to the atmospheric correlation coefficient r(sub 0) which is about 5 cm at sea level. There was no print-thru of the graphite fibers in the cyanate ester surface (the bane of many previous efforts to use cyanate ester mirrors). Our subcontractor has devised a means for developing a 30-50 nm thick layer of graphite free pure ester resin on the surface of the mirrors. This graphite fiber filled material has a thermal expansion coefficient in the 10(exp -8) centimeter per Kelvin range (the same range of expansion coefficient as Zerodur and ULE glasses) and does not take up water and swell, so it is a nearly ideal mirror material in these areas. Unfortunately for these 0.8mm thick faceplates, the number of plies is not enough to result in isometric coverage. Isolated figure irregularities can appear, making it necessary to go to thicker faceplates. The influence function will then only approximate the length of r(sub 0), at higher altitudes or longer wavelengths. The influence function goes as the cube of the thickness, so we are now making a faceplate optimized for

  13. CAG repeat length does not associate with the rate of cerebellar degeneration in spinocerebellar ataxia type 3

    Directory of Open Access Journals (Sweden)

    Shang-Ran Huang

    2017-01-01

    Full Text Available This cross-sectional study investigated the correlation between the CAG repeat length and the degeneration of cerebellum in spinocerebellar ataxia type 3 (SCA3 patients based on neuroimaging approaches. Forty SCA3 patients were recruited and classified into two subgroups according to their CAG repeat lengths (≥74 and <74. We measured each patient's Scale for the Assessment and Rating of Ataxia (SARA score, N-acetylaspartate (NAA/creatine (Cr ratios based on magnetic resonance spectroscopy (MRS, and 3-dimensional fractal dimension (3D-FD values derived from magnetic resonance imaging (MRI results. Furthermore, the 3D-FD values were used to construct structural covariance networks based on graph theoretical analysis. The results revealed that SCA3 patients with a longer CAG repeat length demonstrated earlier disease onset. However, the CAG repeat length did not significantly correlate with their SARA scores, cerebellar NAA/Cr ratios or cerebellar 3D-FD values. Network dissociation between cerebellar regions and parietal-occipital regions was found in SCA3 patients with CAG ≥ 74, but not in those with CAG < 74. In conclusion, the CAG repeat length is uncorrelated with the change of SARA score, cerebellar function and cerebellar structure in SCA3. Nevertheless, a longer CAG repeat length may indicate early structural covariance network dissociation.

  14. Macular Bruch's Membrane Length and Axial Length. The Beijing Eye Study.

    Directory of Open Access Journals (Sweden)

    Jost B Jonas

    Full Text Available To assess whether macular Bruch´s membrane gets lengthened in axial myopia.Using the enhanced depth imaging mode of spectral-domain optical coherence tomography and examining a subgroup of participants of the population-based cross-sectional Beijing Eye Study, we measured the length of Bruch´s membrane ("MacBMLength" from the fovea to the temporal edge of parapapillary gamma zone, and the distance between the fovea and the temporal optic disc border. Parapapillary gamma zone was defined as the parapapillary region without Bruch's membrane. We additionally measured ocular biometric parameters and assessed non-ophthalmologic variables.Measurements of MacBMLength were performed on 322 individuals. MacBMLength (mean: 3.99 ± 0.33 mm; range: 3.17-4.93 mm was not significantly associated with any systemic parameter or ocular biometric parameter. Gamma zone width (mean: 0.18 ± 0.30 mm; range: 0.00-2.61 mm was associated (multivariate analysis; correlation coefficient r:0.80 with longer axial length (P<0.001; standardized correlation coefficient beta: 0.60; non-standardized correlation coefficient B:0.11; 95%CI: 0.09,0.14 and with longer fovea-optic disc border distance (P<0.001; beta:0.28; B:0.19; 95%CI:0.14,0.25, but not with MacBMLength (P = 0.42. Fovea-temporal disc border distance (mean: 4.16 ± 0.44 mm; range: 3.17-5.86 mm was associated (overall correlation coefficient: 0.68 with longer axial length (P<0.001; beta: 0.36; B: 0.10; 95%CI: 0.06, 0.13, after adjusting for flatter anterior chamber depth (P = 0.003; beta:-0.14; B:-0.14; 95%CI: -0.23,-0.05 and wider parapapillary gamma zone (P<0.001; beta:0.42; B:0.62; 95%CI:0.44,0.81.In contrast to parapapillary gamma zone width and fovea-disc border distance, MacBMLength was not significantly associated with axial length. Axial elongation associated increase in fovea-disc distance may predominantly occur through development or elongation of parapapillary gamma zone, while macular Bruch´s membrane

  15. Determination of Arabidopsis thaliana telomere length by PCR.

    Science.gov (United States)

    Vaquero-Sedas, María I; Vega-Palas, Miguel A

    2014-07-02

    In humans, telomere length studies have acquired great relevance because the length of telomeres has been related to natural processes like disease, aging and cancer. However, very little is known about the influence of telomere length on the biology of wild type plants. The length of plant telomeres has been usually studied by Terminal Restriction Fragment (TRF) analyses. This technique requires high amounts of tissue, including multiple cell types, which might be the reason why very little is known about the influence of telomere length on plant natural processes. In contrast, many of the human telomere length studies have focused on homogenous cell populations. Most of these studies have been performed by PCR, using telomeric degenerated primers, which allow the determination of telomere length from small amounts of human cells. Here, we have adapted the human PCR procedure to analyze the length of Arabidopsis thaliana telomeres. This PCR approach will facilitate the analysis of telomere length from low amounts of tissue. We have used it to determine that CG and non CG DNA methylation positively regulates Arabidopsis telomere length.

  16. Maternal telomere length inheritance in the king penguin.

    Science.gov (United States)

    Reichert, S; Rojas, E R; Zahn, S; Robin, J-P; Criscuolo, F; Massemin, S

    2015-01-01

    Telomeres are emerging as a biomarker for ageing and survival, and are likely important in shaping life-history trade-offs. In particular, telomere length with which one starts in life has been linked to lifelong survival, suggesting that early telomere dynamics are somehow related to life-history trajectories. This result highlights the importance of determining the extent to which telomere length is inherited, as a crucial factor determining early life telomere length. Given the scarcity of species for which telomere length inheritance has been studied, it is pressing to assess the generality of telomere length inheritance patterns. Further, information on how this pattern changes over the course of growth in individuals living under natural conditions should provide some insight on the extent to which environmental constraints also shape telomere dynamics. To fill this gap partly, we followed telomere inheritance in a population of king penguins (Aptenodytes patagonicus). We tested for paternal and maternal influence on chick initial telomere length (10 days old after hatching), and how these relationships changed with chick age (at 70, 200 and 300 days old). Based on a correlative approach, offspring telomere length was positively associated with maternal telomere length early in life (at 10 days old). However, this relationship was not significant at older ages. These data suggest that telomere length in birds is maternally inherited. Nonetheless, the influence of environmental conditions during growth remained an important factor shaping telomere length, as the maternal link disappeared with chicks' age.

  17. 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

  18. CCSSM Challenge: Graphing Ratio and Proportion

    Science.gov (United States)

    Kastberg, Signe E.; D'Ambrosio, Beatriz S.; Lynch-Davis, Kathleen; Mintos, Alexia; Krawczyk, Kathryn

    2013-01-01

    A renewed emphasis was placed on ratio and proportional reasoning in the middle grades in the Common Core State Standards for Mathematics (CCSSM). The expectation for students includes the ability to not only compute and then compare and interpret the results of computations in context but also interpret ratios and proportions as they are…

  19. Osmosis and Surface Area to Volume Ratio.

    Science.gov (United States)

    Barrett, D. R. B.

    1984-01-01

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

  20. Key financial ratios can foretell hospital closures.

    Science.gov (United States)

    Lynn, M L; Wertheim, P

    1993-11-01

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

  1. How to use and interpret hormone ratios.

    Science.gov (United States)

    Sollberger, Silja; Ehlert, Ulrike

    2016-01-01

    Hormone ratios have become increasingly popular throughout the neuroendocrine literature since they offer a straightforward way to simultaneously analyze the effects of two interdependent hormones. However, the analysis of ratios is associated with statistical and interpretational concerns which have not been sufficiently considered in the context of endocrine research. The aim of this article, therefore, is to demonstrate and discuss these issues, and to suggest suitable ways to address them. In a first step, we use exemplary testosterone and cortisol data to illustrate that one major concern of ratios lies in their distribution and inherent asymmetry. As a consequence, results of parametric statistical analyses are affected by the ultimately arbitrary decision of which way around the ratio is computed (i.e., A/B or B/A). We suggest the use of non-parametric methods as well as the log-transformation of hormone ratios as appropriate methods to deal with these statistical problems. However, in a second step, we also discuss the complicated interpretation of ratios, and propose moderation analysis as an alternative and oftentimes more insightful approach to ratio analysis. In conclusion, we suggest that researchers carefully consider which statistical approach is best suited to investigate reciprocal hormone effects. With regard to the hormone ratio method, further research is needed to specify what exactly this index reflects on the biological level and in which cases it is a meaningful variable to analyze.

  2. The Divine Ratio and Golden Rectangles.

    Science.gov (United States)

    Cooper, Martin

    1982-01-01

    The material examines aspects of Fibonacci and Lucas sequences, the generation of the Divine Ratio, and the nature of this ratio in golden rectangles, triangles, and figures made up of golden triangles. It is noted Lucas sequence is formed like Fibonacci but has one and three as the first elements. (Author/MP)

  3. Residential long-term care capacity planning: the shortcomings of ratio-based forecasts.

    Science.gov (United States)

    Zhang, Yue; Puterman, Martin L; Atkins, Derek

    2012-05-01

    This paper uses observations from two British Columbia studies to illustrate the shortcomings of widely used ratio-based approaches for residential long-term care capacity planning. It shows that capacity plans based on a fixed ratio of beds per population over age 75 may result in either excess capacity or long wait times for admission. It then investigates the use of linear regression models to obtain a "best" ratio by relating optimal plans derived by rigorous analytical methods to population characteristics and shows that no single ratio applies broadly. While the use of regression is promising, finding these "best" ratios is too analytically complex for general practice. The paper concludes by providing and evaluating an easy-to-use planning method, which we call the average flow model (AFM). The AFM combines demand forecasts with length-of-stay estimates to produce enhanced capacity plans. The AFM is transparent, easily implemented in a spreadsheet and well suited for "what if?" analyses.

  4. Duty ratio of cooperative molecular motors.

    Science.gov (United States)

    Dharan, Nadiv; Farago, Oded

    2012-02-01

    Molecular motors are found throughout the cells of the human body and have many different and important roles. These micromachines move along filament tracks and have the ability to convert chemical energy into mechanical work that powers cellular motility. Different types of motors are characterized by different duty ratios, which is the fraction of time that a motor is attached to its filament. In the case of myosin II (a nonprocessive molecular machine with a low duty ratio), cooperativity between several motors is essential to induce motion along its actin filament track. In this work we use statistical mechanical tools to calculate the duty ratio of cooperative molecular motors. The model suggests that the effective duty ratio of nonprocessive motors that work in cooperation is lower than the duty ratio of the individual motors. The origin of this effect is the elastic tension that develops in the filament which is relieved when motors detach from the track.

  5. 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.

  6. Bond-length distributions for ions bonded to oxygen: alkali and alkaline-earth metals.

    Science.gov (United States)

    Gagné, Olivier Charles; Hawthorne, Frank Christopher

    2016-08-01

    Bond-length distributions have been examined for 55 configurations of alkali-metal ions and 29 configurations of alkaline-earth-metal ions bonded to oxygen, for 4859 coordination polyhedra and 38 594 bond distances (alkali metals), and for 3038 coordination polyhedra and 24 487 bond distances (alkaline-earth metals). Bond lengths generally show a positively skewed Gaussian distribution that originates from the variation in Born repulsion and Coulomb attraction as a function of interatomic distance. The skewness and kurtosis of these distributions generally decrease with increasing coordination number of the central cation, a result of decreasing Born repulsion with increasing coordination number. We confirm the following minimum coordination numbers: ([3])Li(+), ([3])Na(+), ([4])K(+), ([4])Rb(+), ([6])Cs(+), ([3])Be(2+), ([4])Mg(2+), ([6])Ca(2+), ([6])Sr(2+) and ([6])Ba(2+), but note that some reported examples are the result of extensive dynamic and/or positional short-range disorder and are not ordered arrangements. Some distributions of bond lengths are distinctly multi-modal. This is commonly due to the occurrence of large numbers of structure refinements of a particular structure type in which a particular cation is always present, leading to an over-representation of a specific range of bond lengths. Outliers in the distributions of mean bond lengths are often associated with anomalous values of atomic displacement of the constituent cations and/or anions. For a sample of ([6])Na(+), the ratio Ueq(Na)/Ueq(bonded anions) is partially correlated with 〈([6])Na(+)-O(2-)〉 (R(2) = 0.57), suggesting that the mean bond length is correlated with vibrational/displacement characteristics of the constituent ions for a fixed coordination number. Mean bond lengths also show a weak correlation with bond-length distortion from the mean value in general, although some coordination numbers show the widest variation in mean bond length for zero distortion, e.g. Li(+) in

  7. Factors affecting gestation length in the Thoroughbred mare.

    Science.gov (United States)

    Davies Morel, M C G; Newcombe, J R; Holland, S J

    2002-12-16

    In order to assist in the accurate prediction of the timing of parturition in the mare true gestation length, along with the potential effect of a number of factors, was investigated. Data from 433 Thoroughbred foal pregnancies were used. Sequential ultrasonic scanning allowed the true gestation length (fertilisation-parturition) to be ascertained, as apposed to previous work, which used the mating-parturition interval. An average gestation length of 344.1 +/- 0.49 days was evident. Colt foal pregnancies were significantly (P gestation length in all foals (P gestation length range (315-388 days), all resulting in viable foals is noteworthy and of clinical importance when considering the classification of dysmaturity in foals, (ii) mares carrying colt foals due to be born in the middle of the breeding season (April) are likely to have the longer gestation lengths.

  8. Accurate Fiber Length Measurement Using Time-of-Flight Technique

    Science.gov (United States)

    Terra, Osama; Hussein, Hatem

    2016-06-01

    Fiber artifacts of very well-measured length are required for the calibration of optical time domain reflectometers (OTDR). In this paper accurate length measurement of different fiber lengths using the time-of-flight technique is performed. A setup is proposed to measure accurately lengths from 1 to 40 km at 1,550 and 1,310 nm using high-speed electro-optic modulator and photodetector. This setup offers traceability to the SI unit of time, the second (and hence to meter by definition), by locking the time interval counter to the Global Positioning System (GPS)-disciplined quartz oscillator. Additionally, the length of a recirculating loop artifact is measured and compared with the measurement made for the same fiber by the National Physical Laboratory of United Kingdom (NPL). Finally, a method is proposed to relatively correct the fiber refractive index to allow accurate fiber length measurement.

  9. Sperm length evolution in the fungus-growing ants

    DEFF Research Database (Denmark)

    Baer, B.; Dijkstra, M. B.; Mueller, U. G.

    2009-01-01

    the evolution of sperm length. Sperm length does not decrease further in multiply mating leaf-cutting ants, despite substantial further increases in colony size. In a combined analysis, sexual dimorphism explained 63.1% of the variance in sperm length between species. As colony size was not a significant...... in phylogenetically independent contrasts. Some of the remaining variation was explained by the relative size of the sperm-storage organ, but only in the multiply mating leaf-cutting ants, suggesting that sperm-storage constraints become important for the evolution of sperm length in this derived group. Mate number...... affected sperm length to a minor extent, and only in interaction with other predictor variables, suggesting that sperm competition has not been a major selective force for sperm length evolution in these ants....

  10. The length of the glaciers in the world

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.

    2014-01-01

    Glacier length is an important measure of glacier geometry but global glacier inventories are mostly lacking length data. Only recently semi-automated approaches to measure glacier length have been developed and applied regionally. Here we present 5 a first global assessment of glacier length using...... a fully automated method based on glacier surface slope, distance to the glacier margins and a set of trade-off functions. The method is developed for East Greenland, evaluated for the same area as well as for Alaska, and eventually applied to all ∼ 200000 glaciers around the globe. The evaluation...... highlights accurately calculated glacier length where DEM quality is good (East 10 Greenland) and limited precision on low quality DEMs (parts of Alaska). Measured length of very small glaciers is subject to a certain level of ambiguity. The global calculation shows that only about 1.5% of all glaciers...

  11. Far-from-equilibrium measurements of thermodynamic length

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Edward H.; Crooks, Gavin E.

    2008-11-05

    Thermodynamic length is a path function that generalizes the notion of length to the surface of thermodynamic states. Here, we show how to measure thermodynamic length in far-from-equilibrium experiments using the work fluctuation relations. For these microscopic systems, it proves necessary to define the thermodynamic length in terms of the Fisher information. Consequently, the thermodynamic length can be directly related to the magnitude of fluctuations about equilibrium. The work fluctuation relations link the work and the free energy change during an external perturbation on a system. We use this result to determine equilibrium averages at intermediate points of the protocol in which the system is out-of-equilibrium. This allows us to extend Bennett's method to determine the potential of mean force, as well as the thermodynamic length, in single molecule experiments.

  12. Golden Ratio and the heart: A review of divine aesthetics.

    Science.gov (United States)

    Yalta, Kenan; Ozturk, Selcuk; Yetkin, Ertan

    2016-07-01

    In human history, certain mathematical figures or concepts had gained a significant reputation largely due to their occult and esoteric meanings. Among these, Golden Ratio and associated concepts, namely golden proportions, had elicited a tremendous breakthrough in our human awareness and perception regarding mundane and spiritual aspects of physical existence. Golden Ratio or Number (with a numerical value of 1.618) that is also referred to as the Greek letter Phi (φ), has been universally expressed on a line partitioned into two unequal lengths (L, the longer and S, the shorter) in such a manner that L/S=(L+S)/L. Besides, appearing in certain number sequences (Fibonacci Series, etc.), golden proportions, to the consternation of observers, appear to be strikingly prevalent across all levels of physical existence from the innermost structures to the colossal galaxies of the universe potentially labeling these concepts as the measures of divine aesthetics. Accordingly, the human body also serves as an epitome of these mysterious concepts as exemplified by its outward appearance including general stature and extremities along with a variety of inner organ systems. Based on preliminary studies, the human cardiovascular system might also be suggested to serve as a major predilection site of divine aesthetics as measured with Golden Ratio and its allies. This appears to be completely in line with the ancient knowledge associating the human heart with the esoteric and spiritual components of human nature including human soul. Within this context, the present paper primarily aims to discuss human manifestations of divine aesthetics as measured with 'Golden Ratio' and associated indices with a particular and detailed emphasis on their potential link with the human cardiovascular system.

  13. The Dynamic Behaviour of Gears with High Transmission Ratio

    Directory of Open Access Journals (Sweden)

    Ivana Atanasovska

    2012-06-01

    Full Text Available This paper describes the dynamic behaviour of helical gears with new standpoint for calculation of influence variables: mesh teeth stiffness, contact lines lengths and load distribution during mesh period. Nonlinear contact Finite Element Analysis and the new iteration procedure are used for calculation of meshed teeth deformations, stiffness and contact loads. The normal load distribution calculated with this procedure is used for evaluation of nonlinear dynamic analytical model of helical gears motion. Described investigation is especially important for gear pairs with high value of transmission ratio, often used in large transport machines. The presented models and results can be used for helical gears modeling when standard procedures don’t cover the requirements.

  14. The relationship between telomere length and clinicopathologic characteristics in colorectal cancers among Tunisian patients.

    Science.gov (United States)

    Mzahma, Raja; Kharrat, Maher; Fetiriche, Fadhel; Bouasker; Ben Moussa, Mounir; Ben Safta, Zoubeir; Dziri, Chadli; Zaouche, AbdelJelil; Chaabouni-Bouhamed, Habiba

    2015-11-01

    Alterations in telomere dynamics have emerged as having a causative role in carcinogenesis. Both the telomere attrition contribute to tumor initiation via increasing chromosomal instability and that the telomere elongation induces cell immortalization and leads to tumor progression. The objectives of this study are to investigate the dynamics of telomere length in colorectal cancer (CRC) and the clinicopathological parameters implicated. We measured the relative telomere length (RTL) in cancerous tissues and in corresponding peripheral blood leukocytes (PBL) using quantitative PCR (Q-PCR) from 94 patients with CRC. Telomere length correlated significantly in cancer tissues and corresponding PBL (r = 0.705). Overall, cancer tissue had shorter telomeres than PBL (p = 0.033). In both cancer tissue and PBL, the RTL was significantly correlated with age groups (p = 0.008 and p = 0.012, respectively). The RTL in cancer tissue was significantly longer in rectal tumors (p = 0.04) and in the late stage of tumors (p = 0.01). In PBL, the RTL was significantly correlated with the macroscopic aspect of tumors (p = 0.02). In addition, the telomere-length ratio of cancer to corresponding PBL increased significantly with late-stage groups. Shortening of the telomere was detected in 44.7%, elongation in 36.2%, and telomeres were unchanged in 19.1% of 94 tumors. Telomere shortening occurred more frequently in the early stage of tumors (p = 0.01). This study suggests that the telomere length in PBL is affected by the macroscopic aspect of tumors and that telomere length in cancer tissues is a marker for progression of CRC and depends on tumor-origin site.

  15. The relationship between language proficiency and surgical length of stay following cardiac bypass surgery.

    Science.gov (United States)

    Tang, Erin W; Go, Jeremy; Kwok, Andrea; Leung, Bonnie; Lauck, Sandra; Wong, Sabrina T; Taipale, Priscilla G; Ratner, Pamela A

    2016-10-01

    Anglophone nurses face the challenge of communicating health information to patients who do not speak or understand English. Limited English-proficient patients are at higher risk of misinterpreting health information teaching. Successful recovery after coronary artery bypass graft surgery requires patients' engagement with healthcare professionals and active participation in therapies and related undertakings. Determination of whether limited English-proficient patients undergoing coronary artery bypass graft surgery recover at the same pace as the general population is of interest. This study examined whether limited English-proficient patients had prolonged post-operative length of stay following coronary artery bypass graft surgery. The patients' length of stay with regard to a clinical pathway target was also examined. A retrospective medical record review of all patients undergoing isolated coronary artery bypass graft surgery in a 2-year period was conducted. A screening tool was developed to identify limited English-proficient patients through examination of their medical records. A total of 691 of 712 (97.1%) patients met the inclusion criteria; 103 (14.9%) patients were identified as limited English-proficient. The post-operative median length of stay of limited English-proficient patients was 7 days compared with 6 days for the English-proficient patients (p = 0.007). Limited English-proficient patients had higher infection rates (29.1%) vs. English-proficient patients (16.7%) (odds ratio = 2.05 (95% confidence intervals 1.27-3.30)). Post-operative infection was the strongest predictor of length of stay and fully mediated the relationship between language proficiency and length of stay. When compared with English-proficient patients, limited English-proficient patients had greater infection rates, which were associated with longer length of stay. These findings warrant examination of the mechanisms through which post-operative infections are acquired by

  16. Is length an appropriate estimator to characterize pulmonary alveolar capillaries? A critical evaluation in the human lung

    DEFF Research Database (Denmark)

    Mühlfeld, Christian; Weibel, Ewald R.; Hahn, Ute

    2010-01-01

    Stereological estimations of total capillary length have been used to characterize changes in the alveolar capillary network (ACN) during developmental processes or pathophysiological conditions. Here, we analyzed whether length estimations are appropriate to describe the 3D nature of the ACN. Semi...... resulted in a mean of 2,746 km (SD: 722 km). Because of the geometry of the ACN both approaches carry an unpredictable bias. The bias incurred by the design-based approach is proportional to the ratio between radius and length of the capillary segments in the ACN, the number of branching points...... and the winding of the capillaries. The model-based approach is biased because of the real noncylindrical shape of capillaries and the network structure. In conclusion, the estimation of the total length of capillaries in the ACN cannot be recommended as the geometry of the ACN does not fulfill the requirements...

  17. The effect of gas assisted length on polymer melt extrusion based on the gas-assisted extrusion technique

    Science.gov (United States)

    Wan, B.; Ren, Z.; Liu, G. D.; Huang, X. Y.

    2017-02-01

    In this study, the gas-assisted technique was used into the process of polymer melt extrusion to overcome the extrudate swell problem. The gas length is an important factors in the gas-assisted extrusion technique. To ascertain the mechanism of the gas-assisted extrusion technique, and to determine the optimal gas length, the effect of gas length on the extrudate swell ratio of melt was numerically investigated. In finite element numerical simulation, PTT constitutive model and full slip boundary condition were used to achieve the gas-assisted mode. Compared with the traditional no gas-assisted extrusion, numerical results showed that the extrudate swell problem was well eliminated by the gas-assisted method. Moreover, the extrudate swell of melt decreased with the increasing of the gas length because the pressure and shear stress of melt were greatly decreased. Moreover, the flow velocity of melt is uniform at the die outlet.

  18. Gestation length and birth weight in relation to intake of marine n-3 fatty acids.

    Science.gov (United States)

    Olsen, S F; Hansen, H S; Secher, N J; Jensen, B; Sandström, B

    1995-03-01

    It has been hypothesized that marine n-3 fatty acids ingested during pregnancy prolong duration of pregnancy and increase fetal growth rate in humans. By a combined self-administered questionnaire and interview applied in the 30th week of gestation we assessed dietary intake of marine n-3 fatty acids and energy in a population-based sample of 965 pregnant Danish women; in a random 14% subsample we also measured marine n-3 fatty acids relative to arachidonic acid (FA-ratio) in erythrocytes. Mean intake of marine n-3 fatty acids was 0.25 (95% range 0-0.75) g/d. We could detect no association between n-3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate.

  19. Influence of alkane chain length on adsorption on an α-alumina surface by MD simulations

    Energy Technology Data Exchange (ETDEWEB)

    Turgut, C. [Department of Science and Analysis of Materials (SAM), CRP-Gabriel Lippmann, L-4422 Belvaux (Luxembourg); Institut Jean Lamour (IJL) CNRS UMR 7198, Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, F-54506 Vandoeuvre-les-Nancy Cedex (France); Pandiyan, S. [Department of Science and Analysis of Materials (SAM), CRP-Gabriel Lippmann, L-4422 Belvaux (Luxembourg); Mether, L. [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 (Finland); Belmahi, M. [Institut Jean Lamour (IJL) CNRS UMR 7198, Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, F-54506 Vandoeuvre-les-Nancy Cedex (France); Nordlund, K. [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 (Finland); Philipp, P., E-mail: philipp@lippmann.lu [Department of Science and Analysis of Materials (SAM), CRP-Gabriel Lippmann, L-4422 Belvaux (Luxembourg)

    2015-06-01

    Plasma surface techniques provide both an efficient and ecological tool for the functionalization of surfaces. Hence, a proper understanding of the plasma–surface interactions of precursors and radicals during the deposition process is of great importance. Especially during the initial deposition process, the deposition of molecules and fragments is difficult to investigate by experimental techniques and import insights can be obtained by molecular dynamics simulations. In this work, the reactive force field developed by the group of Kieffer at the University of Michigan was used to study the adsorption of single linear alkane chains on an α-alumina surface. The chain length was changed from 6 backbone carbon atoms to 16 carbon atoms, the deposition energy from 0.01 to 10 eV and the incidence angle from 0° to 60° with respect to the surface normal. Results show that the adsorption depends a lot on the ratio of deposition energy to alkane chain length and the incidence angle. More grazing incidence reduces the adsorption probability and a low ratio of energy to chain length increases it.

  20. On some length biased inequalities for reliability measures

    Directory of Open Access Journals (Sweden)

    Oluyede BroderickO

    2000-01-01

    Full Text Available In this note, inequalities for length biased and the original residual life function and equilibrium distribution function with monotone hazard rate and mean residual life functions are derived. We also obtain estimates of the length biased probability density function and hazard function under random censoring. Finally, the Bayesian exponential reliability estimate under length biased sampling using a conjugate prior for the scale parameter is given.

  1. Telomere length trajectory and its determinants in persons with coronary artery disease: longitudinal findings from the heart and soul study.

    Directory of Open Access Journals (Sweden)

    Ramin Farzaneh-Far

    Full Text Available BACKGROUND: Leukocyte telomere length, an emerging marker of biological age, has been shown to predict cardiovascular morbidity and mortality. However, the natural history of telomere length in patients with coronary artery disease has not been studied. We sought to investigate the longitudinal trajectory of telomere length, and to identify the independent predictors of telomere shortening, in persons with coronary artery disease. METHODOLOGY/PRINCIPAL FINDINGS: In a prospective cohort study of 608 individuals with stable coronary artery disease, we measured leukocyte telomere length at baseline, and again after five years of follow-up. We used multivariable linear and logistic regression models to identify the independent predictors of leukocyte telomere trajectory. Baseline and follow-up telomere lengths were normally distributed. Mean telomere length decreased by 42 base pairs per year (p<0.001. Three distinct telomere trajectories were observed: shortening in 45%, maintenance in 32%, and lengthening in 23% of participants. The most powerful predictor of telomere shortening was baseline telomere length (OR per SD increase = 7.6; 95% CI 5.5, 10.6. Other independent predictors of telomere shortening were age (OR per 10 years = 1.6; 95% CI 1.3, 2.1, male sex (OR = 2.4; 95% CI 1.3, 4.7, and waist-to-hip ratio (OR per 0.1 increase = 1.4; 95% CI 1.0, 2.0. CONCLUSIONS/SIGNIFICANCE: Leukocyte telomere length may increase as well as decrease in persons with coronary artery disease. Telomere length trajectory is powerfully influenced by baseline telomere length, possibly suggesting negative feedback regulation. Age, male sex, and abdominal obesity independently predict telomere shortening. The mechanisms and reversibility of telomeric aging in cardiovascular disease deserve further study.

  2. Length-weight and length-length relationships of seven loach species (Teleostei: Cypriniformes from five localities in northern Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Ashwini Keskar

    2015-12-01

    Full Text Available Length-weight (LWR and length-length (LLR relationships of seven loach species (Teleostei: Cypriniformes: Botia striata, Lepidocephalichthys thermalis, Paracanthocobitis mooreh, Indoreonectes evezardi, Nemacheilus anguilla, Nemachilichthys rueppelli and Schistura denisoni were studied from five localities within the Krishna River system of the Indian Western Ghats: Lonawala (Indrayani River, Paud (Mula River, Warje (Mutha River, Bhor (Nira River and Patan (Koyna River.  With the exception of L. thermalis all species are endemic to peninsular India, and to our knowledge this is the first presentation of LWR and LLR data for them.  New maximum lengths are also reported for I. evezardi, N. anguilla, N. rueppelli and S. denisoni. 

  3. Telomere length variations in aging and age-related diseases.

    Science.gov (United States)

    Rizvi, Saliha; Raza, Syed Tasleem; Mahdi, Farzana

    2014-01-01

    Telomeres are gene sequences present at chromosomal ends and are responsible for maintaining genome integrity. Telomere length is maximum at birth and decreases progressively with advancing age and thus is considered as a biomarker of chronological aging. This age associated decrease in the length of telomere is linked to various ageing associated diseases like diabetes, hypertension, Alzheimer's disease, cancer etc. and their associated complications. Telomere length is a result of combined effect of oxidative stress, inflammation and repeated cell replication on it, and thus forming an association between telomere length and chronological aging and related diseases. Thus, decrease in telomere length was found to be important in determining both, the variations in longevity and age-related diseases in an individual. Ongoing and progressive research in the field of telomere length dynamics has proved that aging and age-related diseases apart from having a synergistic effect on telomere length were also found to effect telomere length independently also. Here a short description about telomere length variations and its association with human aging and age-related diseases is reviewed.

  4. 21 CFR 26.5 - Length of transition period.

    Science.gov (United States)

    2010-04-01

    ... RECOGNITION OF PHARMACEUTICAL GOOD MANUFACTURING PRACTICE REPORTS, MEDICAL DEVICE QUALITY SYSTEM AUDIT REPORTS... Specific Sector Provisions for Pharmaceutical Good Manufacturing Practices § 26.5 Length of...

  5. Effects of Ethanol Pulping on the Length of Bamboo Cellulose

    Institute of Scientific and Technical Information of China (English)

    Tao Yang; Liao Junhe; Luo Xuegang

    2006-01-01

    On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effects on the length of cellulose, which is clearly reduced with adding ethanol and acid. The margin of length of cellulose become smaller with the increase of the catalyzer. When the ethanol concentration was 70%, the concentration of acid was 0.3% and some NaOH was used as catalyzer, the length of cellulose was the longest.

  6. How does harvest size vary with hunting season length?

    DEFF Research Database (Denmark)

    Sunde, Peter; Asferg, Tommy

    2014-01-01

    season length (population management/ethical/other). In non-sedentary species, changes in bag size correlated positively with changes in season length (overall response: b = 0.54, 95%CI: 0.14-0.95): reducing the hunting season to 50% of its initial length would on average result in a 31% reduction (95...... species, changes in season length had no effect on bag size. Our results suggest that manipulating hunting seasons of duration ≥ 1 month by less than 50% is generally inefficient as a means of predictably changing harvest rates. This may be because recreational hunters either invest a fixed effort or aim...

  7. Ultra-low-loss tapered optical fibers with minimal lengths

    CERN Document Server

    Nagai, Ryutaro

    2014-01-01

    We design and fabricate ultra-low-loss tapered optical fibers (TOFs) with minimal lengths. We first optimize variations of the torch scan length using the flame-brush method for fabricating TOFs with taper angles that satisfy the adiabaticity criteria. We accordingly fabricate TOFs with optimal shapes and compare their transmission to TOFs with a constant taper angle and TOFs with an exponential shape. The highest transmission measured for TOFs with an optimal shape is in excess of 99.7 % with a total TOF length of only 23 mm, whereas TOFs with a constant taper angle of 2 mrad reach 99.6 % transmission for a 63 mm TOF length.

  8. Maintaining realism in auditory length-perception experiments

    DEFF Research Database (Denmark)

    Kirkwood, Brent Christopher

    2005-01-01

    Humans are capable of hearing the lengths of wooden rods dropped onto hard floors. In an attempt to understand the influence of the stimulus presentation method for testing this kind of everyday listening task, listener performance was compared for three presentation methods in an auditory length......-estimation experiment. A comparison of the length-estimation accuracy for the three presentation methods indicates that the choice of presentation method is important for maintaining realism and for maintaining the acoustic cues utilized by listeners in perceiving length....

  9. Maintaining realism in auditory length-perception experiments

    DEFF Research Database (Denmark)

    Kirkwood, Brent Christopher

    2005-01-01

    Humans are capable of hearing the lengths of wooden rods dropped onto hard floors. In an attempt to understand the influence of the stimulus presentation method for testing this kind of everyday listening task, listener performance was compared for three presentation methods in an auditory length......-estimation experiment. A comparison of the length-estimation accuracy for the three presentation methods indicates that the choice of presentation method is important for maintaining realism and for maintaining the acoustic cues utilized by listeners in perceiving length....

  10. Influence of Slot Defect Length on Magnetic Flux Leakage

    Institute of Scientific and Technical Information of China (English)

    Songling HUANG; Luming LI; Haiqing YANG; Keren SHI

    2004-01-01

    A key issue, which influences the applications of magnetic flux leakage testing, is defect quantification. There have been many research on the relationship between width, depth and magnetic flux leakage of slot defect. However, the length factor is often ignored. The relationship between characteristics of defect leakage field and defect length was investigated. The magnetic flux leakages of a series of plate specimens with the same width, same depth and different length slot defects were tested under the same magnetizing conditions. Testing results show that defect length is an important parameter needed to consider in quantifying defects.

  11. CALIPSO lidar ratio retrieval over the ocean.

    Science.gov (United States)

    Josset, Damien; Rogers, Raymond; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali; Zhai, Peng-Wang

    2011-09-12

    We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type.

  12. Ultrasonographic assessment of cervical length in pregnancies scheduled for a cesarean delivery: prediction of early spontaneous onset of labor.

    Science.gov (United States)

    Rizzo, Giuseppe; Aiello, Elisa; Pietrolucci, Maria Elena; Arduini, Domenico

    2016-10-01

    To investigate whether the cervical length measured by transvaginal ultrasound at 35 to 36 weeks of gestation is predictive of spontaneous early onset of labor in pregnancies scheduled for elective cesarean section (CS). This was a prospective observational study on 167 women scheduled for elective CS at 39 weeks of gestation. The cervical length was measured ultrasonographycally at 35 to 36 weeks of gestation and the pregnancies characteristics were recorded. The presence or absence of spontaneous onset of labor before the time scheduled for elective CS was related to cervical length and pregnancies characteristics. Of the 167 pregnancies enrolled, 25 (14.97%) underwent early spontaneous onset of labor before the time scheduled for the elective CS. The cervical length was significantly shorter in these women when compared with those delivering with an elective CS (21 vs. 30 mm z=5.49 Ponset of labor in univariate analysis (P=0.01). Multivariate logistic regression analysis showed that cervical length (adjusted odds ratio 1.40; 95% confidence interval (CI) 1.22-1.61; P≤0.0001) was the only predictor for the early onset of labor. The area under the receiver-operating characteristics curve for the prediction of early onset of labor was 0.844 (95% CI 0.738-0.950) for cervical length as test variable. Kaplan-Meier analysis demonstrated that a cervical length onset of labor in pregnancies scheduled for CS and may be useful in individualizing the gestational age for elective CS.

  13. Population structure, length-weight and length-length relationships of six populations of the Bartail Flathead Platycephalus indicus (Scorpaeniformes: Platycephalidae along the Persian Gulf coastal waters

    Directory of Open Access Journals (Sweden)

    Hamed Mousavi-Sabet

    2015-01-01

    Full Text Available The size frequency distribution for age structure, length-weight (LWR and length-length (LLR relationships of six populations of Platycephalus indicus along the Persian Gulf coastal waters in Iran are reported.  A total of 180 P. indicus specimens were studied from six localities including Charak, Bandar-Abbas, Shif, Motaf, Khur-Musa and Bahrekan.  The maximum standard length recorded for the studied populations ranged between 300 to 510 mm and the b values of the length-weight relationships ranged between 3.0 and 3.2.  The obtained results indicated isometric growth patterns for all these populations with the exception of the Bahrekan population which showed a positive allometric growth pattern.  The LLR between the total and standard lengths in these populations were found to be highly significant.  The results would be useful for further studies on population assessment and sustainable conservation of the fish along the Persian Gulf coastal waters.

  14. Rayleigh length dependent SHG conversion at 488nm using a monolithic DBR tapered diode laser

    Science.gov (United States)

    Blume, G.; Uebernickel, M.; Fiebig, C.; Paschke, K.; Ginolas, A.; Eppich, B.; Güther, R.; Erbert, G.

    2008-02-01

    We present a study of the single pass SHG conversion as a function of the Rayleigh length (RL) and beam diameter (BD) using a monolithic distributed Bragg reflector (DBR) tapered laser. The DBR tapered laser has a 6th order surface grating and a ridge waveguide. Single longitudinal mode emission at 978nm with a side-mode suppression ratio of more than 40dB and at an output power of 2.7W at 15°C have been obtained in continuous wave operation. The beam was collimated using an aspheric and a cylindrical lens and focused using a variety of lenses with various focal lengths. The resulting caustics were acquired using a camera and used for SHG in a 5cm periodically poled LiNbO 3 (PPLN) crystal. This allowed an investigation of the dependency of the SHG conversion efficiency on the RLs and BDs. We obtained 330mW of output power at 488nm using the optimal focus length. The experiments showed that an optimum conversion requires longer focal length's then forecasted by Boyd-Kleinman's theory, which is explained due to the partial coherence. We developed an extension of that theory to account for that partial coherence, which bases in principle on a mismatch related general Agrawal's nonlinear integration kernel. We use this theory to explain the dependence of the SHG efficiency from the beam propagation factor M2.

  15. Turbulent transfer coefficient and roughness length in a high-altitude lake, Tibetan Plateau

    Science.gov (United States)

    Li, Zhaoguo; Lyu, Shihua; Zhao, Lin; Wen, Lijuan; Ao, Yinhuan; Wang, Shaoying

    2016-05-01

    A persistent unstable atmospheric boundary layer was observed over Lake Ngoring, caused by higher temperature on the water surface compared with the overlying air. Against this background, the eddy covariance flux data collected from Lake Ngoring were used to analyse the variation of transfer coefficients and roughness lengths for momentum, heat and moisture. Results are discussed and compared with parameterization schemes in a lake model. The drag coefficient and momentum roughness length rapidly decreased with increasing wind velocity, reached a minimum value in the moderate wind velocity and then increased slowly as wind velocity increased further. Under weak wind conditions, the surface tension or small scale capillary wave becomes more important and increases the surface roughness. The scalar roughness length ratio was much larger than unity under weak wind conditions, and it decreased to values near unity as wind velocity exceeded 4.0 m s-1. The lake model could not reproduce well the variation of drag coefficient, or momentum roughness length, versus wind velocity in Lake Ngoring, but it did simulate well the sensible heat and latent heat fluxes, as a result of complementary opposite errors.

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

    Science.gov (United States)

    Frynta, Daniel; Vejvodová, Tereza; Šimková, Olga

    2016-06-01

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

  17. 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...

  18. Financial Ratios and Perceived Household Financial Satisfaction

    Directory of Open Access Journals (Sweden)

    Scott Garrett

    2013-08-01

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

  19. The Panofsky ratio in 3He

    Science.gov (United States)

    Corriveau, F.; Hasinoff, M. D.; Measday, D. F.; Poutissou, J.-M.; Salomon, M.

    1987-11-01

    The branching ratios have been measured for γ-ray channels produced by π- stopping in liquid 3He. The results for the Panofsky ratio are P3 = ω( π-3He → π0t)/ ω( π-3He → γt) = 2.83 ± 0.07, and for the ratio of the radiative breakup channels, B3 = ω)( π-3He → γnd + γnnp)/ ω( π-3He → γt) = 1.35 ±0.11.

  20. Comparison of shape recovery ratios of single-piece poly(methyl methacrylate) intraocular lens haptics.

    Science.gov (United States)

    Kimura, W; Kimura, T; Sawada, T; Kikuchi, T; Nagai, H; Yamada, Y

    1993-09-01

    We studied shape recovery ratios of several single- and three-piece intraocular lens (IOL) haptics after conducting compression tests for various lengths of time. Results of the comparison of poly(methyl methacrylate) (PMMA) IOL haptics configured of a single piece and of three pieces showed a superior shape recovery ratio for single-piece haptics. Comparisons of the shape recovery ratios among single-piece PMMA haptics and conventional three-piece haptics made of polyvinylidene fluoride (PVDF), PMMA, and polypropylene (PP) revealed that the shape recovery ratio of single-piece PMMA haptics was higher than the ratios of the conventional three-piece PMMA and PP haptics. The ratios of two of three of the single-piece PMMA haptics, however, were lower than the ratios of three-piece PVDF haptics. The form and manufacturing procedures of haptics likely have a significant impact on the shape recovery ratio of haptics, even those made of the same material. Since decentration after IOL surgery could be caused by the condition of the patient's lenticular capsule and Zinn's zonule, it is difficult to conclude that the shape recovery ratio is the only factor in IOL stability. Nevertheless, this study indicates that IOL haptics that cause less decentration and have better mechanical properties should be developed.