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Sample records for length density rld

  1. Modeling root length density of field grown potatoes under different irrigation strategies and soil textures using artificial neural networks

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Sepaskhah, Ali Reza; Andersen, Mathias Neumann

    2014-01-01

    Root length density (RLD) is a highly wanted parameter for use in crop growth modeling but difficult to measure under field conditions. Therefore, artificial neural networks (ANNs) were implemented to predict the RLD of field grown potatoes that were subject to three irrigation strategies and three...... soil textures with different soil water status and soil densities. The objectives of the study were to test whether soil textural information, soil water status, and soil density might be used by ANN to simulate RLD at harvest. In the study 63 data pairs were divided into data sets of training (80......) of the eight input variables: soil layer intervals (D), percentages of sand (Sa), silt (Si), and clay (Cl), bulk density of soil layers (Bd), weighted soil moisture deficit during the irrigation strategies period (SMD), geometric mean particle size diameter (dg), and geometric standard deviation (σg...

  2. Minimal length, Friedmann equations and maximum density

    International Nuclear Information System (INIS)

    Awad, Adel; Ali, Ahmed Farag

    2014-01-01

    Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

  3. Minimal length, Friedmann equations and maximum density

    Energy Technology Data Exchange (ETDEWEB)

    Awad, Adel [Center for Theoretical Physics, British University of Egypt,Sherouk City 11837, P.O. Box 43 (Egypt); Department of Physics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Ali, Ahmed Farag [Centre for Fundamental Physics, Zewail City of Science and Technology,Sheikh Zayed, 12588, Giza (Egypt); Department of Physics, Faculty of Science, Benha University,Benha, 13518 (Egypt)

    2014-06-16

    Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

  4. Variation of basic density and fibre length in Lonchocarpus capassa ...

    African Journals Online (AJOL)

    Within tree radial and axial variations of wood basic density and fibre length of. Lonchocarpus capassa (Rolfe) were investigated using three mature defect free trees from Kilosa District, Tanzania. Samples for determination of wood basic density and fibre length were collected from the butt, the middle and the tip of the

  5. Chemical theory and modelling through density across length scales

    International Nuclear Information System (INIS)

    Ghosh, Swapan K.

    2016-01-01

    One of the concepts that has played a major role in the conceptual as well as computational developments covering all the length scales of interest in a number of areas of chemistry, physics, chemical engineering and materials science is the concept of single-particle density. Density functional theory has been a versatile tool for the description of many-particle systems across length scales. Thus, in the microscopic length scale, an electron density based description has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids. Density concept has been used in the form of single particle number density in the intermediate mesoscopic length scale to obtain an appropriate picture of the equilibrium and dynamical processes, dealing with a wide class of problems involving interfacial science and soft condensed matter. In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related property density functions has been found to be quite appropriate. The basic ideas underlying the versatile uses of the concept of density in the theory and modelling of materials and phenomena, as visualized across length scales, along with selected illustrative applications to some recent areas of research on hydrogen energy, soft matter, nucleation phenomena, isotope separation, and separation of mixture in condensed phase, will form the subject matter of the talk. (author)

  6. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    the fundamental aspects of the mechanisms operating in the early stages of pitting. (leading to passivity breakdown ... The sample thickness was monitored by quartz crystal system during growth. The electrochemical ... system, N is the number density at a depth z and b is the coherent nuclear scat- tering length. From the ...

  7. Maximum length scale in density based topology optimization

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Wang, Fengwen

    2017-01-01

    The focus of this work is on two new techniques for imposing maximum length scale in topology optimization. Restrictions on the maximum length scale provide designers with full control over the optimized structure and open possibilities to tailor the optimized design for broader range...... of manufacturing processes by fulfilling the associated technological constraints. One of the proposed methods is based on combination of several filters and builds on top of the classical density filtering which can be viewed as a low pass filter applied to the design parametrization. The main idea...

  8. Research Notes Patterns of thorn length, density, type and colour in ...

    African Journals Online (AJOL)

    Research Notes Patterns of thorn length, density, type and colour in African Acacias. JJ Midgley, MA Botha, D Balfour. Abstract. In Acacia no trade-off occurs between thorn length and thorn density and no correlation exists between thorn length and leaf length. By relating thorn length and density to leaf length it is clear that ...

  9. Density Functional Theory and Materials Modeling at Atomistic Length Scales

    Directory of Open Access Journals (Sweden)

    Swapan K. Ghosh

    2002-04-01

    Full Text Available Abstract: We discuss the basic concepts of density functional theory (DFT as applied to materials modeling in the microscopic, mesoscopic and macroscopic length scales. The picture that emerges is that of a single unified framework for the study of both quantum and classical systems. While for quantum DFT, the central equation is a one-particle Schrodinger-like Kohn-Sham equation, the classical DFT consists of Boltzmann type distributions, both corresponding to a system of noninteracting particles in the field of a density-dependent effective potential, the exact functional form of which is unknown. One therefore approximates the exchange-correlation potential for quantum systems and the excess free energy density functional or the direct correlation functions for classical systems. Illustrative applications of quantum DFT to microscopic modeling of molecular interaction and that of classical DFT to a mesoscopic modeling of soft condensed matter systems are highlighted.

  10. Length scale and manufacturability in density-based topology optimization

    DEFF Research Database (Denmark)

    Lazarov, Boyan Stefanov; Wang, Fengwen; Sigmund, Ole

    2016-01-01

    Since its original introduction in structural design, density-based topology optimization has been applied to a number of other fields such as microelectromechanical systems, photonics, acoustics and fluid mechanics. The methodology has been well accepted in industrial design processes where it can...... performance and in many cases can completely destroy the optimality of the solution. Therefore, the goal of this paper is to review recent advancements in obtaining manufacturable topology-optimized designs. The focus is on methods for imposing minimum and maximum length scales, and ensuring manufacturable...

  11. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    Abstract. We report the density depth profile of an as-deposited Ni film and density profile for the same film after controlled electrochemical corrosion by chloride ions, mea- sured by unpolarized neutron reflectometry. The neutron reflectometry measurement of the film after corrosion shows density degradation along the ...

  12. Scattering length density profile of Ni film under controlled corrosion ...

    Indian Academy of Sciences (India)

    We report the density depth profile of an as-deposited Ni film and density profile for the same film after controlled electrochemical corrosion by chloride ions, measured by unpolarized neutron reflectometry. The neutron reflectometry measurement of the film after corrosion shows density degradation along the thickness of ...

  13. Sugarcane root length density and distribution from root intersection counting on a trench-profile Densidade de comprimento e distribuição de raízes de cana-de-açúcar a partir da contagem de intersecção de raízes na parede do perfil

    Directory of Open Access Journals (Sweden)

    Mateus Carvalho Basilio de Azevedo

    2011-02-01

    Full Text Available Root length density (RLD is a critical feature in determining crops potential to uptake water and nutrients, but it is difficult to be measured. No standard method is currently available for assessing RLD in the soil. In this study, an in situ method used for other crops for studying root length density and distribution was tested for sugarcane (Saccharum spp.. This method involved root intersection counting (RIC on a Rhodic Eutrudox profile using grids with 0.05 x 0.05 m and modeling RLD from RIC. The results were compared to a conventional soil core-sampled method (COR (volume 0.00043 m³. At four dates of the cropping season in three tillage treatments (plowing soil, minimum tillage and direct planting, with eight soil depths divided in 0.1 m soil layer (between 0-0.6 and 1.6-1.8 m and three horizontal distances from the row (0-0.23, 0.23-0.46 and 0.46-0.69 m, COR and RIC methods presented similar RLD results. A positive relationship between COR and RIC was found (R² = 0.76. The RLD profiles considering the average of the three row distances per depth obtained using COR and RIC (mean of four dates and 12 replications were close and did not differ at each depth of 0.1 m within a total depth of 0.6 m. Total RLD between 0 and 0.6 m was 7.300 and 7.100 m m-2 for COR and RIC respectively. For time consumption, the RIC method was tenfold less time-consuming than COR and RIC can be carried out in the field with no need to remove soil samples. The RLD distribution in depth and row distance (2-D variability by RIC can be assessed in relation to the soil properties in the same soil profiles. The RIC method was suitable for studying these 2-D (depth and row distance in the soil profile relationships between soil, tillage and root distribution in the field.A densidade de comprimento de raízes (DCR é uma característica importante para determinar o potencial de absorção de água e nutrientes das plantas, mas é difícil de ser medida. Nenhum m

  14. The probability density function of completed length of service (CLS ...

    African Journals Online (AJOL)

    ... functions this paper estimates the functions for some secondary schools in Enugu State. Wastage probabilities are calculated, survivor functions estimated. The accompanying standard errors are also obtained. Key words: Manpower Planning, Length of Service, Modelling, Survivor Functions. [Global Jnl Mathematical Sci ...

  15. The relationship between fission track length and track density in apatite

    International Nuclear Information System (INIS)

    Laslett, G.M.; Gleadow, A.J.W.; Duddy, I.R.

    1984-01-01

    Fission track dating is based upon an age equation derived from a random line segment model for fission tracks. This equation contains the implicit assumption of a proportional relationship between the true mean length of fission tracks and their track density in an isotropic medium. Previous experimental investigation of this relationship for both spontaneous and induced tracks in apatite during progressive annealment model in an obvious fashion. Corrected equations relating track length and density for apatite, an anisotropic mineral, show that the proportionality in this case is between track density and a length factor which is a generalization of the mean track length combining the actual length and crystallographic orientation of the track. This relationship has been experimentally confirmed for induced tracks in Durango apatite, taking into account bias in sampling of the track lengths, and the effect of the bulk etching velocity. (author)

  16. Interspecies Interactions in Relation to Root Distribution Across the Rooting Profile in Wheat-Maize Intercropping Under Different Plant Densities

    Directory of Open Access Journals (Sweden)

    Yifan Wang

    2018-04-01

    Full Text Available In wheat-maize intercropping systems, the maize is often disadvantageous over the wheat during the co-growth period. It is unknown whether the impaired growth of maize can be recovered through the enhancement of the belowground interspecies interactions. In this study, we (i determined the mechanism of the belowground interaction in relation to root growth and distribution under different maize plant densities, and (ii quantified the “recovery effect” of maize after wheat harvest. The three-year (2014–2016 field experiment was conducted at the Oasis Agriculture Research Station of Gansu Agricultural University, Wuwei, Northwest China. Root weight density (RWD, root length density (RLD, and root surface area density (RSAD, were measured in single-cropped maize (M, single-cropped wheat (W, and three intercropping systems (i wheat-maize intercropping with no root barrier (i.e., complete belowground interaction, IC, (ii nylon mesh root barrier (partial belowground interaction, IC-PRI, and (iii plastic sheet root barrier (no belowground interaction, IC-NRI. The intercropped maize was planted at low (45,000 plants ha−1 and high (52,000 plants ha−1 densities. During the wheat/maize co-growth period, the IC treatment increased the RWD, RLD, and RSAD of the intercropped wheat in the 20–100 cm soil depth compared to the IC-PRI and IC-NRI systems; intercropped maize had 53% lower RWD, 81% lower RLD, and 70% lower RSAD than single-cropped maize. After wheat harvest, the intercropped maize recovered the growth with the increase of RWD by 40%, RLD by 44% and RSAD by 11%, compared to the single-cropped maize. Comparisons among the three intercropping systems revealed that the “recovery effect” of the intercropped maize was attributable to complete belowground interspecies interaction by 143%, the compensational effect due to root overlap by 35%, and the compensational effect due to water and nutrient exchange (CWN by 80%. The higher maize plant

  17. Lee-Yang-inspired functional with a density-dependent neutron-neutron scattering length

    Science.gov (United States)

    Grasso, M.; Lacroix, D.; Yang, C. J.

    2017-05-01

    Inspired by the low-density Lee-Yang expansion for the energy of a dilute Fermi gas of density ρ and momentum kF, we introduce here a Skyrme-type functional that contains only s -wave terms and provides, at the mean-field level, (i) a satisfactory equation of state for neutron matter from extremely low densities up to densities close to the equilibrium point, and (ii) a good-quality equation of state for symmetric matter at density scales around the saturation point. This is achieved by using a density-dependent neutron-neutron scattering length a (ρ ) which satisfies the low-density limit (for Fermi momenta going to zero) and has a density dependence tuned in such a way that the low-density constraint |a (ρ ) kF|≤1 is satisfied at all density scales.

  18. Modeling relaxation length and density of acacia mangium wood using gamma - ray attenuation technique

    International Nuclear Information System (INIS)

    Tamer A Tabet; Fauziah Abdul Aziz

    2009-01-01

    Wood density measurement is related to the several factors that influence wood quality. In this paper, density, relaxation length and half-thickness value of eight ages, 3, 5, 7, 10, 11, 13 and 15 year-old of Acacia mangium wood were determined using gamma radiation from 137 Cs source. Results show that Acacia mangium tree of age 3 year has the highest relaxation length of 83.33 cm and least density of 0.43 gcm -3 , while the tree of age 15 year has the least Relaxation length of 28.56 cm and highest density of 0.76 gcm -3 . Results also show that the 3 year-old Acacia mangium wood has the highest half thickness value of 57.75 cm and 15 year-old tree has the least half thickness value of 19.85 cm. Two mathematical models have been developed for the prediction of density, variation with relaxation length and half-thickness value of different age of tree. A good agreement (greater than 85% in most cases) was observed between the measured values and predicted ones. Very good linear correlation was found between measured density and the age of tree (R2 = 0.824), and between estimated density and Acacia mangium tree age (R2 = 0.952). (Author)

  19. Effects of fine root length density and root biomass on soil preferential flow in forest ecosystems

    Directory of Open Access Journals (Sweden)

    Yinghu Zhang

    2015-04-01

    Full Text Available Aim of study: The study was conducted to characterize the impacts of plant roots systems (e.g., root length density and root biomass on soil preferential flow in forest ecosystems. Area of study: The study was carried out in Jiufeng National Forest Park, Beijing, China. Material and methods: The flow patterns were measured by field dye tracing experiments. Different species (Sophora japonica Linn,Platycladus orientalis Franco, Quercus dentata Thunbwere quantified in two replicates, and 12 soil depth were applied. Plant roots were sampled in the sieving methods. Root length density and root biomass were measured by WinRHIZO. Dye coverage was implied in the image analysis, and maximum depth of dye infiltration by direct measurement. Main results: Root length density and root biomass decreased with the increasing distance from soil surface, and root length density was 81.6% higher in preferential pathways than in soil matrix, and 66.7% for root biomass with respect to all experimental plots. Plant roots were densely distributed in the upper soil layers. Dye coverage was almost 100% in the upper 5-10 cm, but then decreased rapidly with soil depth. Root length density and root biomass were different from species: Platycladus orientalis Franco > Quercus dentata Thunb > Sophora japonica Linn. Research highlights: The results indicated that fine roots systems had strong effects on soil preferential flow, particularly root channels enhancing nutrition transport across soil profiles in forest dynamics.

  20. On the neutron scattering length density of proteins in H2O/D2O

    Science.gov (United States)

    Efimova, Y. M.; van Well, A. A.; Hanefeld, U.; Wierczinski, B.; Bouwman, W. G.

    2004-07-01

    The structure of the protein layers adsorbed at different interfaces can be determined by using neutron-reflection and small-angle neutron scattering. For highlighting the adsorbed protein layer at the interface, the technique of contrast-variation by changing the H2O/D2O ratio, is often used. For determining the scattering length density, both the protein volume in solution and the total scattering length of the protein is needed. The volume is calculated from the amino-acid sequence. For calculating the scattering length, the H/D exchange of the labile protons of the protein should be taken into account. For monitoring the H/D exchange, Positive Electrospray Ionization Mass Spectroscopy was applied. We compare experimental results for the exchange in lysozyme and β-casein with theoretical calculations. The importance of using the correct protein scattering-length density is elucidated by simultaneous model fitting to neutron reflection data at different water contrasts.

  1. On the neutron scattering length density of proteins in H2O/D2O

    International Nuclear Information System (INIS)

    Efimova, Y.M.; Well, A.A. van; Hanefeld, U.; Wierczinski, B.; Bouwman, W.G.

    2004-01-01

    The structure of the protein layers adsorbed at different interfaces can be determined by using neutron-reflection and small-angle neutron scattering. For highlighting the adsorbed protein layer at the interface, the technique of contrast-variation by changing the H 2 O/D 2 O ratio, is often used. For determining the scattering length density, both the protein volume in solution and the total scattering length of the protein is needed. The volume is calculated from the amino-acid sequence. For calculating the scattering length, the H/D exchange of the labile protons of the protein should be taken into account. For monitoring the H/D exchange, Positive Electrospray Ionization Mass Spectroscopy was applied. We compare experimental results for the exchange in lysozyme and β-casein with theoretical calculations. The importance of using the correct protein scattering-length density is elucidated by simultaneous model fitting to neutron reflection data at different water contrasts

  2. Flame Treatment of Low-Density Polyethylene: Surface Chemistry Across the Length Scale

    NARCIS (Netherlands)

    Song, Jing; Gunst, Ullrich; Arlinghaus, Heinrich F.; Vancso, Gyula J.

    2007-01-01

    The relationship between surface chemistry and morphology of flame treated low-density polyethylene (LDPE) was studied by various characterization techniques across different length scales. The chemical composition of the surface was determined on the micrometer scale by X-ray photoelectron

  3. Compensation in Root Water Uptake Models Combined with Three-Dimensional Root Length Density Distribution

    NARCIS (Netherlands)

    Heinen, M.

    2014-01-01

    A three-dimensional root length density distribution function is introduced that made it possible to compare two empirical uptake models with a more mechanistic uptake model. Adding a compensation component to the more empirical model resulted in predictions of root water uptake distributions

  4. [Changes in bone mineral density of postmenopausal women in relation to the menstrual cycle length].

    Science.gov (United States)

    Enchev, E; Dimitrakova, E

    2010-01-01

    There is a strong relationship between the age of menarche, the length of the menstrual cycle and menstrual bleeding and fracture risk in the postmenopausal period. Evaluation of the menstrual cycle length and lumbar bone mineral density in postmenopausal women. We investigated three groups of postmenopausal women (each - n = 50). The first group included women with menstrual duration of 27 days during reproductive age, the second group included postmenopausal women with menstrual duration of 28 days during the reproductive age, and the third group consisted of postmenopausal women with menstrual duration of 30 days during reproductive age. The average age of women was 58.80 +/- 0.94 y. in the first group, 60.36 +/- 5.12 y. in the second group and -61.84 +/- 0.80 y. in the third group. Age, age of menarche, number of childbirths, length of the menstrual cycle and menstrual bleeding, and lumbar bone density were assessed and registered for each woman. We used DXA in a anterior-posterior projection to assess the bone density of the lumbar spine; the obtained results are shown in gram/cm2. The women from the third group, with average menstrual cycle length of 30 days, reach menopause at a significantly later age, have longer menstrual cycle and shorter menstrual bleeding, and higher lumbar spine bone density, compared to the other two groups. The data from our research show that women with anamnesis for average normal menstrual cycle length of 30 days reach menopausal period at a significantly later age, have shorter menstrual bleeding, and higher lumbar spine bone density compared to those with shorter menstrual cycle duration (27 and 28 days).

  5. Length-scale effect due to periodic variation of geometrically necessary dislocation densities

    DEFF Research Database (Denmark)

    Oztop, M. S.; Niordson, Christian Frithiof; Kysar, J. W.

    2013-01-01

    Strain gradient plasticity theories have been successful in predicting qualitative aspects of the length scale effect, most notably the increase in yield strength and hardness as the size of the deforming volume decreases. However new experimental methodologies enabled by recent developments...... the microstructure of deformed metals in addition to the size effect. Recent GND measurements have revealed a distribution of length scales that evolves within a metal undergoing plastic deformation. Furthermore, these experiments have shown an accumulation of GND densities in cell walls as well as a variation...... of the saturation value of dislocation densities in these cell walls and dislocation structures. In this study, a strain gradient plasticity framework is extended by incorporating the physical quantities obtained from experimental observations: the quasi-periodicity and the saturation value of GND densities...

  6. Single crystal cupric oxide nanowires: Length- and density-controlled growth and gas-sensing characteristics

    Science.gov (United States)

    Duc, Le Duy; Le, Dang Thi Thanh; Duy, Nguyen Van; Hoa, Nguyen Duc; Hieu, Nguyen Van

    2014-04-01

    Nanowire structured p-type CuO semiconductor is a promising material for gas-sensing applications because of its unique electrical and optical properties. In this study, we demonstrate the length and density controlled synthesis of single crystal CuO nanowires (CuO NWs) by a simple and convenient thermal oxidation of high-purity copper foils in ambient atmosphere. The density and length of the CuO NWs are controlled by varying the oxidation temperature and heating duration to investigate their growth mechanism. As-synthesized materials are characterized by different techniques, such as X-ray diffraction, field emission-scanning electron microscopy, and high-resolution transmission electron microscopy. The gas-sensing characteristics of the CuO NWs are tested using hydrogen and ethanol gases. The results show that the CuO NWs could potentially sense hydrogen and ethanol gases given a working temperature of 400 °C.

  7. Kernel density estimation applied to bond length, bond angle, and torsion angle distributions.

    Science.gov (United States)

    McCabe, Patrick; Korb, Oliver; Cole, Jason

    2014-05-27

    We describe the method of kernel density estimation (KDE) and apply it to molecular structure data. KDE is a quite general nonparametric statistical method suitable even for multimodal data. The method generates smooth probability density function (PDF) representations and finds application in diverse fields such as signal processing and econometrics. KDE appears to have been under-utilized as a method in molecular geometry analysis, chemo-informatics, and molecular structure optimization. The resulting probability densities have advantages over histograms and, importantly, are also suitable for gradient-based optimization. To illustrate KDE, we describe its application to chemical bond length, bond valence angle, and torsion angle distributions and show the ability of the method to model arbitrary torsion angle distributions.

  8. Axial length and cone density as assessed with adaptive optics in myopia

    Directory of Open Access Journals (Sweden)

    Supriya Dabir

    2015-01-01

    Full Text Available Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL. Subjects and Methods: Twenty-five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM. Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455-16,404 ± 4494/mm 2 respectively. There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.

  9. A parameterization of momentum roughness length and displacement height for a wide range of canopy densities

    Directory of Open Access Journals (Sweden)

    A. Verhoef

    1997-01-01

    Full Text Available Values of the momentum roughness length, z0, and displacement height, d, derived from wind profiles and momentum flux measurements, are selected from the literature for a variety of sparse canopies. These include savannah, tiger-bush and several row crops. A quality assessment of these data, conducted using criteria such as available fetch, height of wind speed measurement and homogeneity of the experimental site, reduced the initial total of fourteen sites to eight. These datapoints, combined with values carried forward from earlier studies on the parameterization of z0 and d, led to a maximum number of 16 and 24 datapoints available for d and z0, respectively. The data are compared with estimates of roughness length and displacement height as predicted from a detailed drag partition model, R92 (Raupach, 1992, and a simplified version of this model, R94 (Raupach, 1994. A key parameter in these models is the roughness density or frontal area index, λ. Both the comprehensive and the simplified model give accurate predictions of measured z0 and d values, but the optimal model coefficients are significantly different from the ones originally proposed in R92 and R94. The original model coefficients are based predominantly on measured aerodynamic parameters of relatively closed canopies and they were fitted `by eye'. In this paper, best-fit coefficients are found from a least squares minimization using the z0 and d values of selected good-quality data for sparse canopies and for the added, mainly closed canopies. According to a statistical analysis, based on the coefficient of determination (r2, the number of observations and the number of fitted model coefficients, the simplified model, R94, is deemed to be the most appropriate for future z0 and d predictions. A CR value of 0.35 and a cd1 value of about 20 are found to be appropriate for a large range of canopies varying in density from closed to very sparse. In this case, 99% of the total variance

  10. Enhanced photo-H2 production by Rhodopseudomonas faecalis RLD-53 immobilization on activated carbon fibers

    International Nuclear Information System (INIS)

    Xie, Guo-Jun; Liu, Bing-Feng; Ding, Jie; Xing, De-Feng; Ren, Hong-Yu; Guo, Wan-Qian; Ren, Nan-Qi

    2012-01-01

    Activated carbon fibers (ACFs) were firstly applied as fluidized solid carrier to immobilize photo-fermentative bacteria (PFB) for H 2 production in batch culture. The observations by scanning electronic microscopy (SEM) demonstrated the close interaction between ACFs and PFB. The amount of immobilized bacteria and the performance of H 2 production were strongly affected by specific surface area, length and amount of ACFs, respectively. Large specific surface area provided more surface attachment sites and more PFB were immobilized. ACFs with proper length avoided intertwining with each other and better fluidized during reactor operation. Excessive amount of ACFs not only limited the light conversion efficiency, but also increased biofilm detachment, resulting in low H 2 yield. The maximum yield (3.08 mol H 2 mol −1 acetate) and rate (32.85 ml l −1 h −1 ) of H 2 production were obtained, using specific surface area (1500 m 2 g −1 ), length (1 mm) and amount (0.8 g l −1 ) of ACFs. Compared with the conventional solid carriers, ACFs were effective solid carriers to immobilize PFB for improving H 2 production, due to bacteria immobilized on the external surface of fluidized ACFs and formed a layer of dense biofilm. -- Highlights: ► ACFs were firstly used to immobilize photo-fermentative bacteria for H 2 production. ► ACFs were fluidized in the reactor during the operation. ► Bacteria covered on the external surface of ACFs and formed dense biofilm. ► Each bacterium on the ACFs could absorb the light and convert substrate into H 2 .

  11. Localization and density of phoretic deutonymphs of the mite Uropoda orbicularis (Parasitiformes: Mesostigmata) on Aphodius beetles (Aphodiidae) affect pedicel length

    Science.gov (United States)

    Bajerlein, Daria; Witaliński, Wojciech

    2014-04-01

    The phoretic stage of Uropodina mites is a deutonymph with developed morphological adaptations for dispersal by insects. Phoretic deutonymphs are able to produce a pedicel, a stalk-like temporary attachment structure that connects the mite with the carrier. The aim of our study was to determine whether localization and density of phoretic deutonymphs on the carrier affect pedicel length. The study was conducted on a common phoretic mite— Uropoda orbicularis (Uropodina) and two aphodiid beetles— Aphodius prodromus and Aphodius distinctus. Our results show that pedicel length is influenced by the localization of deutonymphs on the body of the carrier. The longest pedicels are produced by deutonymphs attached to the upper part of elytra, whereas deutonymphs attached to femora and trochanters of the third pair of legs and the apex of elytra construct the shortest pedicels. In general, deutonymphs attached to more exposed parts of the carrier produce longer pedicels, whereas shorter pedicels are produced when deutonymphs are fixed to non-exposed parts of the carrier. A second factor influencing pedicel length is the density of attached deutonymphs. Mean pedicel length and deutonymph densities were highly correlated: higher deutonymph density leads to the formation of longer pedicels. The cause for this correlation is discussed, and we conclude that pedicel length variability can increase successful dispersal.

  12. Dental plaque microcosm response to bonding agents containing quaternary ammonium methacrylates with different chain lengths and charge densities.

    Science.gov (United States)

    Zhou, Han; Li, Fang; Weir, Michael D; Xu, Hockin H K

    2013-11-01

    Antibacterial bonding agents are promising to combat bacteria and caries at tooth-restoration margins. The objectives of this study were to incorporate new quaternary ammonium methacrylates (QAMs) to bonding agent and determine the effects of alkyl chain length (CL) and quaternary amine charge density on dental plaque microcosm bacteria response for the first time. Six QAMs were synthesized with CL=3, 6, 9, 12, 16, 18. Each QAM was incorporated into Scotchbond multi-purpose (SBMP). To determine the charge density effect, dimethylaminododecyl methacrylate (DMAHDM, CL=16) was mixed into SBMP at mass fraction=0%, 2.5%, 5%, 7.5%, 10%. Charge density was measured using a fluorescein dye method. Dental plaque microcosm using saliva from ten donors was tested. Bacteria were inoculated on resins. Early-attachment was tested at 4h. Biofilm colony-forming units (CFU) were measured at 2 days. Incorporating QAMs into SBMP reduced bacteria early-attachment. Microcosm biofilm CFU for CL=16 was 4 log lower than SBMP control. Charge density of bonding agent increased with DMAHDM content. Bacteria early-attachment decreased with increasing charge density. Biofilm CFU at 10% DMAHDM was reduced by 4 log. The killing effect was similarly-strong against total microorganisms, total streptococci, and mutans streptococci. Increasing alkyl chain length and charge density of bonding agent was shown for the first time to decrease microcosm bacteria attachment and reduce biofilm CFU by 4 orders of magnitude. Novel antibacterial resins with tailored chain length and charge density are promising for wide applications in bonding, cements, sealants and composites to inhibit biofilms and caries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Dental plaque microcosm response to bonding agents containing quaternary ammonium methacrylates with different chain lengths and charge densities

    Science.gov (United States)

    Zhou, Han; Li, Fang; Weir, Michael D.; Xu, Hockin H.K.

    2013-01-01

    Objectives Antibacterial bonding agents are promising to combat bacteria and caries at tooth-restoration margins. The objectives of this study were to incorporate new quaternary ammonium methacrylates (QAMs) to bonding agent and determine the effects of alkyl chain length (CL) and quaternary amine charge density on dental plaque microcosm bacteria response for the first time. Methods Six QAMs were synthesized with CL = 3, 6, 9, 12, 16, 18. Each QAM was incorporated into Scotchbond Multi-purpose (SBMP). To determine the charge density effect, dimethylaminododecyl methacrylate (DMAHDM, CL = 16) was mixed into SBMP at mass fraction = 0%, 2.5%, 5%, 7.5%, 10%. Charge density was measured using a fluorescein dye method. Dental plaque microcosm using saliva from ten donors was tested. Bacteria were inoculated on resins. Early-attachment was tested at 4 hours. Biofilm colony-forming units (CFU) were measured at 2 days. Results Incorporating QAMs into SBMP reduced bacteria early-attachment. Microcosm biofilm CFU for CL = 16 was 4 log lower than SBMP control. Charge density of bonding agent increased with DMAHDM content. Bacteria early-attachment decreased with increasing charge density. Biofilm CFU at 10% DMAHDM was reduced by 4 log. The killing effect was similarly-strong against total microorganisms, total streptococci, and mutans streptococci. Conclusions Increasing alkyl chain length and charge density of bonding agent was shown for the first time to decrease microcosm bacteria attachment and reduce biofilm CFU by 4 orders of magnitude. Novel antibacterial resins with tailored chain length and charge density are promising for wide applications in bonding, cements, sealants and composites to inhibit biofilms and caries. PMID:23948394

  14. The distribution of fine root length density for six artificial afforestation tree species in Loess Plateau of Northwest China

    Directory of Open Access Journals (Sweden)

    Shengqi Jian

    2015-04-01

    Full Text Available Aim of the study: Data about the distribution of fine root length density (FRLD is important to understand the ecophysiology of vegetation. This is particularly true when models are applied to describe ecohydrology and vegetation function. However, there is yet limited knowledge of root distributions in semi-arid regions. The aim of this study is to investigate the distribution of fine roots for six typical afforestation tree species in Loess Plateau and its relationships with soil environmental factors. Area of study: Loess Plateau (NW of China. Material and methods: We quantified the fine root length density distribution of six typical afforestation tree species by soil core method, and the soil properties also were investigated. Main results: More than 50% of fine root length was concentrated at depths between 0 and 40 cm in vertical direction. In horizontal direction, most of fine roots concentrated near the trunk. Results showed a significant negative correlation between vertical distribution of FRLD and soil water content, a positive correlation between FRLD and organic matter and total N is significant, and a negative correlation with bulk density. No relationships were found with total C and particle size distribution in any soil layer for the six tree species. Stepwise multiple linear regression confirmed that changes in different soil properties significantly affected the variation in FRLD for each tree species, total N had strong and positive relationships with FRLD. Research highlights: These measurements provide valuable data for modelling of ecosystem water use and productivity.

  15. Effects of cloud-point grafting, chain length, and density of PEG layers on competitive adsorption of ocular proteins

    DEFF Research Database (Denmark)

    Kingshott, P.; Thissen, H.; Griesser, H.J.

    2002-01-01

    The effects of pinning density, chain length, and 'cloud point' (CP) versus non-CP grafting conditions have been studied on the ability of polyethylene glycol (PEG) layers to minimize adsorption from a multicomponent (lysozyme, human serum albumin (HSA), IgG and lactoferrin) protein solution......-ray photoelectron spectroscopy (XPS) showed that under these conditions, PEG(ald)(2) produced a thick linear PEG layer, most likely by aldol condensation. Protein adsorption was assessed using XPS and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS) in the surface mode...... density) r.f.g.d. polymer layers. The PEG graft density was varied also by increasing the temperature and salt (K2SO4) content of the grafting solution; it reached a maximum at the CP of the PEGs. The CP reaction conditions were critical for producing PEG layers capable of minimizing protein adsorption. X...

  16. A high-density genetic map of cucumber derived from Specific Length Amplified Fragment sequencing (SLAF-seq).

    Science.gov (United States)

    Xu, Xuewen; Xu, Ruixue; Zhu, Biyun; Yu, Ting; Qu, Wenqin; Lu, Lu; Xu, Qiang; Qi, Xiaohua; Chen, Xuehao

    2014-01-01

    High-density genetic map provides an essential framework for accurate and efficient genome assembly and QTL fine mapping. Construction of high-density genetic maps appears more feasible since the advent of next-generation sequencing (NGS), which eases SNP discovery and high-throughput genotyping of large population. In this research, a high-density genetic map of cucumber (Cucumis sativus L.) was successfully constructed across an F2 population by a recently developed Specific Length Amplified Fragment sequencing (SLAF-seq) method. In total, 18.69 GB of data containing 93,460,000 paired-end reads were obtained after preprocessing. The average sequencing depth was 44.92 in the D8 (female parent), 42.16 in the Jin5-508 (male parent), and 5.01 in each progeny. 79,092 high-quality SLAFs were detected, of which 6784 SLAFs were polymorphic, and 1892 of the polymorphic markers met the requirements for constructing genetic map. The genetic map spanned 845.87 cm with an average genetic distance of 0.45 cm. It is a reliable linkage map for fine mapping and molecular breeding of cucumber for its high marker density and well-ordered markers.

  17. Influence of shrub cover vegetal and slope length on soil bulk density

    International Nuclear Information System (INIS)

    Bienes, R.; Jimenez, R.; Ruiz, M.; Garcia-Estringana, P.; Marques, M. J.

    2009-01-01

    In arid and semiarid environments of the Mediterranean climate, the shrub species play an important role in the revegetation of abandoned lands, which enables to control the soil losses, organic material and water. In this article are compared the results obtained under different revegetation in abandoned lands in the central area of Spain. In these revegetation has been used two native shrubs: A triplex halimus (Ah) and Retama sphaerocarpa (Rs), and were analyzed the influence of these revegetation in the contents of organic material of soil and apparent density in 5 years time after planting. As control, have been considered the pieces of ground with spontaneous vegetation abandoned in the same date that the shrubs revegetation. Atriplex halimus gives to the soil a covering capable to intercept a big amount of water drops absorbing a great amount part of the kinetic energy of the rain, while provides a microclimates as a result of be able to soften the wind, the temperature and the evaporation-transpiration, which makes it efficient to control the erosion and the desertification (Le Houerou, 2000). Retama sphaerocarpa was chosen because it is a native shrub very characteristic, and, due to its symbiosis with the Bradyrhizobium, enriches the soil in nitrogen, which is taken by the nitrophilous species enhancing the spontaneous vegetal covering. (Author) 9 refs.

  18. The effect of the cation alkyl chain length on density and diffusion in dialkylpyrrolidinium bis(mandelato)borate ionic liquids.

    Science.gov (United States)

    Filippov, Andrei; Taher, Mamoun; Shah, Faiz Ullah; Glavatskih, Sergei; Antzutkin, Oleg N

    2014-12-28

    The physicochemical properties of ionic liquids are strongly affected by the selective combination of the cations and anions comprising the ionic liquid. In particular, the length of the alkyl chains of ions has a clear influence on the ionic liquid's performance. In this paper, we study the self-diffusion of ions in a series of halogen-free boron-based ionic liquids (hf-BILs) containing bis(mandelato)borate anions and dialkylpyrrolidinium cations with long alkyl chains CnH2n+1 with n from 4 to 14 within a temperature range of 293-373 K. It was found that the hf-BILs with n = 4-7 have very similar diffusion coefficients, while hf-BILs with n = 10-14 exhibit two liquid sub-phases in almost the entire temperature range studied (293-353 K). Both liquid sub-phases differ in their diffusion coefficients, while values of the slower diffusion coefficients are close to those of hf-BILs with shorter alkyl chains. To explain the particular dependence of diffusion on the alkyl chain length, we examined the densities of the hf-BILs studied here. It was shown that the dependence of the density on the number of CH2 groups in long alkyl chains of cations can be accurately described using a "mosaic type" model, where regions of long alkyl chains of cations (named 'aliphatic' regions) and the residual chemical moieties in both cations and anions (named 'ionic' regions) give additive contributions. Changes in density due to an increase in temperature and the number of CH2 groups in the long alkyl chains of cations are determined predominantly by changes in the free volume of the 'ionic' regions, while 'aliphatic' regions are already highly compressed by van der Waals forces, which results in only infinitesimal changes in their free volumes with temperature.

  19. Association between leukocyte telomere length and bone mineral density in women 25-93 years of age

    DEFF Research Database (Denmark)

    Nielsen, Barbara Rubek; Linneberg, Allan; Bendix, Laila

    2015-01-01

    completed a health and lifestyle questionnaire. The associations were estimated by regression models that considered age, body mass index (BMI), menopause, physical activity, alcohol consumption and smoking habits. We found a statistically significant unadjusted association between LTL and age (estimate......Leukocyte telomere length (LTL) and bone mineral density (BMD) are associated with health and mortality. Because osteoporosis is an age-related condition and LTL is considered to be a biomarker of aging, we hypothesized that shorter LTL could predict lower BMD. The aim of our study was to assess...... whether there is an association of LTL with BMD and to determine whether this possible association is independent of age. The BMDs of the lumbar spine (LS), femoral neck (FN) and total hip (TH) were evaluated in 460 women using DXA. LTL was analyzed using quantitative polymerase chain reaction. The women...

  20. Axial Length Variation Impacts on Superficial Retinal Vessel Density and Foveal Avascular Zone Area Measurements Using Optical Coherence Tomography Angiography.

    Science.gov (United States)

    Sampson, Danuta M; Gong, Peijun; An, Di; Menghini, Moreno; Hansen, Alex; Mackey, David A; Sampson, David D; Chen, Fred K

    2017-06-01

    To evaluate the impact of image magnification correction on superficial retinal vessel density (SRVD) and foveal avascular zone area (FAZA) measurements using optical coherence tomography angiography (OCTA). Participants with healthy retinas were recruited for ocular biometry, refraction, and RTVue XR Avanti OCTA imaging with the 3 × 3-mm protocol. The foveal and parafoveal SRVD and FAZA were quantified with custom software before and after correction for magnification error using the Littman and the modified Bennett formulae. Relative changes between corrected and uncorrected SRVD and FAZA were calculated. Forty subjects were enrolled and the median (range) age of the participants was 30 (18-74) years. The mean (range) spherical equivalent refractive error was -1.65 (-8.00 to +4.88) diopters and mean (range) axial length was 24.42 mm (21.27-28.85). Images from 13 eyes were excluded due to poor image quality leaving 67 for analysis. Relative changes in foveal and parafoveal SRVD and FAZA after correction ranged from -20% to +10%, -3% to +2%, and -20% to +51%, respectively. Image size correction in measurements of foveal SRVD and FAZA was greater than 5% in 51% and 74% of eyes, respectively. In contrast, 100% of eyes had less than 5% correction in measurements of parafoveal SRVD. Ocular biometry should be performed with OCTA to correct image magnification error induced by axial length variation. We advise caution when interpreting interocular and interindividual comparisons of SRVD and FAZA derived from OCTA without image size correction.

  1. Effects of time-series length and gauge network density on rainfall climatology estimates in Latin America

    Science.gov (United States)

    Maeda, E.; Arevalo, J.; Carmona-Moreno, C.

    2012-04-01

    Despite recent advances in the development of satellite sensors for monitoring precipitation at high spatial and temporal resolutions, the assessment of rainfall climatology still relies strongly on ground-station measurements. The Global Historical Climatology Network (GHCN) is one of the most popular stations database available for the international community. Nevertheless, the spatial distribution of these stations is not always homogeneous and the record length largely varies for each station. This study aimed to evaluate how the number of years recorded in the GHCN stations and the density of the network affect the uncertainties of annual rainfall climatology estimates in Latin America. The method applied was divided in two phases. In the first phase, Monte Carlo simulations were performed to evaluate how the number of samples and the characteristics of rainfall regime affect estimates of annual average rainfall. The simulations were performed using gamma distributions with pre-defined parameters, which generated synthetic annual precipitation records. The average and dispersion of the synthetic records were then estimated through the L-moments approach and compared with the original probability distribution that was used to produce the samples. The number of records (n) used in the simulation varied from 10 to 150, reproducing the range of number of years typically found in meteorological stations. A power function, in the form RMSE= f(n) = c.na, where the coefficients were defined as a function of the rainfall statistical dispersion, was applied to fit the errors. In the second phase of the assessment, the results of the simulations were extrapolated to real records obtained by the GHCN over Latin America, creating estimates of errors associated with number of records and rainfall characteristics in each station. To generate a spatially-explicit representation of the uncertainties, the errors in each station were interpolated using the inverse distance

  2. Influence of anterior chamber depth, anterior chamber volume, axial length, and lens density on postoperative endothelial cell loss.

    Science.gov (United States)

    Reuschel, Anna; Bogatsch, Holger; Oertel, Nicole; Wiedemann, Renate

    2015-05-01

    To evaluate the influence of anterior chamber depth (ACD), anterior chamber volume (ACV), lens density (LD), and axial length (AL) as risk factors on endothelial cell loss 3 months after cataract surgery. We enrolled 47 patients with senile cataract who were operated between July 2012 and March 2013 by the same surgeon using torsional phacoemulsification. Preoperatively, we measured ACD, ACV, and LD using the Oculus Pentacam®. The AL was determined using the IOL Master®. Primary outcomes were central endothelial density (ECD) and corrected distance visual acuity (CDVA) 3 months after surgery We evaluated the effect of ACD, ACV, LD, and AL as possible risk factors of postoperative percentage endothelial cell loss (ECL). The median age was 72 years. The median CDVA before surgery was 0.5 improving to 1.0 postoperatively. The median ECL was 5.2 % (range 1.7 %-7.6 %). These results are comparable to our previous study (median ECL 6.9 % after 3 months) [Reuschel et al. (2010) J Cataract Refract Surg]. The median ACD in our study was 2.56 mm (range 2.26 mm-2.8 mm). Median ACV was 144 mm(3) (range 121 mm(3)-158 mm(3)]. The median LD was 12.4 (range 11.4-13.7). Median AL was 23.1 mm (range 22.7 mm-23.9 mm). Our correlation analysis showed no significant correlation between ACD, ACV, LD, AL, and postoperative ECL. ACD, ACV, AL, and LD were not identified as risk factors of postoperative endothelial cell loss in our analysis.

  3. Loss of PiT-2 results in abnormal bone development and decreased bone mineral density and length in mice.

    Science.gov (United States)

    Yamada, Shunsuke; Wallingford, Mary C; Borgeia, Suhaib; Cox, Timothy C; Giachelli, Cecilia M

    2018-01-01

    Normal bone mineralization requires phosphate oversaturation in bone matrix vesicles, as well as normal regulation of phosphate metabolism via the interplay among bone, intestine, and kidney. In turn, derangement of phosphate metabolism greatly affects bone function and structure. The type III sodium-dependent phosphate transporters, PiT-1 and PiT-2, are believed to be important in tissue phosphate metabolism and physiological bone formation, but their requirement and molecular roles in bone remain poorly investigated. In order to decipher the role of PiT-2 in bone, we examined normal bone development, growth, and mineralization in global PiT-2 homozygous knockout mice. PiT-2 deficiency resulted in reduced vertebral column, femur, and tibia length as well as mandibular dimensions. Micro-computed tomography analysis revealed that bone mineral density in the mandible, femur, and tibia were decreased, indicating that maintenance of bone function and structure is impaired in both craniofacial and long bones of PiT-2 deficient mice. Both cortical and trabecular thickness and mineral density were reduced in PiT-2 homozygous knockout mice compared with wild-type mice. These results suggest that PiT-2 is involved in normal bone development and growth and plays roles in cortical and trabecular bone metabolism feasibly by regulating local phosphate transport and mineralization processes in the bone. Further studies that evaluate bone cell-specific loss of PiT-2 are now warranted and may yield insight into complex mechanisms of bone development and growth, leading to identification of new therapeutic options for patients with bone diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Modeling of flame lift-off length in diesel low-temperature combustion with multi-dimensional CFD based on the flame surface density and extinction concept

    Science.gov (United States)

    Azimov, Ulugbek; Kim, Ki-Seong; Bae, Choongsik

    2010-07-01

    Low-Temperature Combustion (LTC) is becoming a promising technology for simultaneously reducing soot and NOx emissions from diesel engines. LTC regimes are evaluated by the flame lift-off length - the distance from the injector orifice to the location of hydroxyl luminescence closest to the injector in the flame jet. Various works have been dedicated to successful simulations of lifted flames of a diesel jet by use of various combustion modeling approaches. In this work, flame surface density and flamelet concepts were used to model the diesel lift-off length under LTC conditions. Numerical studies have been performed with the ECFM3Z model, n-Heptane and diesel fuels to determine the flame lift-off length and its correlation with soot formation under quiescent conditions. The numerical results showed good agreement with experimental data, which were obtained from an optically accessible constant volume chamber and presented at the Engine Combustion Network (ECN) of Sandia National Laboratories. It was shown that at a certain distance downstream from the injector orifice, stoichiometric scalar dissipation rate matched the extinction scalar dissipation rate. This computed extinction scalar dissipation rate correlated well with the flame lift-off length. For the range of conditions investigated, adequate quantitative agreement was obtained with the experimental measurements of lift-off length under various ambient gas O2 concentrations, ambient gas temperatures, ambient gas densities and fuel injection pressures. The results showed that the computed lift-off length values for most of the conditions lay in a reasonable range within the quasi-steady lift-off length values obtained from experiments. However, at ambient temperatures lower than 1000 K, the lift-off length values were under-predicted by the numerical analysis. This may be due to the use of the droplet evaporation model as it is believed that evaporation has a strong effect on the lift-off length.

  5. Influence of facial hair length, coarseness, and areal density on seal leakage of a tight-fitting half-face respirator.

    Science.gov (United States)

    Floyd, Evan L; Henry, J Blake; Johnson, David L

    2018-04-01

    OSHA regulations state that an employer shall not permit tight-fitting respirators to be worn by employees who have facial hair that comes between the skin and facepiece seal. Studies have shown that facial hair in the face seal zone can increase penetration and decrease the fit factor (FF), although the relationship between the amount and characteristics of facial hair and the increase in penetration is not well quantified. This article examines the influence of facial hair length, areal density, and coarseness on FF for one model of half-face elastomeric negative-pressure air purifying respirator. Quantitative fit tests (QNFT) were performed on 19 subjects with beards initially 0.500-in long and subsequently trimmed to 0.250, 0.125, and 0.063 in, then after a razor shave. Three fit tests were performed at each of the 5 lengths, for 285 total tests. The average diameter and areal density of cheek and chin hair were measured. Penetration was modeled as a function of hair length category, beard areal density, and hair coarseness. FF decreased with beard length, especially beyond 0.125 in. However, passing FF scores were achieved on all tests by all subjects at the smooth shave and 0.063 in conditions, and 98% of tests were passed at 0.125 in; seven subjects passed all tests at all conditions. Chin and cheek areal densities were significantly different and were only weakly correlated. Beard hair diameters were normally distributed across subjects (mean 76 µm, standard deviation 7.4 µm). Beard length and areal density, but not coarseness, were statistically significant predictors of fit using an arcsine transformed penetration model. FF decreased with increasing beard length, especially beyond 0.125 in, although FF with a "stubble" beard did not differ significantly from a smooth shave. FF also decreased with increasing areal beard hair density. Beard length and areal density negatively influence FF. However, tight-fitting half-face negative-pressure respirator

  6. On the scattering length density of proteins in H2O/D2O. Determination of H-D exchange using ES+I-MS

    International Nuclear Information System (INIS)

    Efimova, Y.M.; Wierczinski, B.; Well, A.A. Van; Bouwman, W.G.; Hanefeld, U.

    2005-01-01

    Neutron reflectometry is an excellent technique to determine the structure of a protein layer adsorbed at a solid interface. The use of contrast-variation makes it possible to highlight the adsorbed protein layer. The neutron scattering lengths of D and H have opposite signs. By choosing the H 2 O/D 2 O ratio, the scattering length density can be made equal to that of the adsorbing substrate. To determine the scattering length density of protein, both its volume and its scattering length in solution is needed. To calculate the scattering length, the H-D exchange of the labile protons of the protein should be taken into account. For monitoring the H-D exchange, electrospray ionization mass spectroscopy (ES + I-MS) was applied. It is shown that ES + I-MS is the appropriate technique for quantitative analysis of the H-D exchange. Experimental results for the exchange in lysozyme and β-casein with theoretical calculations are compared. (author)

  7. On Lowering the Error Floor of Short-to-Medium Block Length Irregular Low Density Parity Check Codes

    OpenAIRE

    Abdu-Aguye, Umar-Faruk

    2018-01-01

    Edited version embargoed until 22.03.2019 Full version: Access restricted permanently due to 3rd party copyright restrictions. Restriction set on 22.03.2018 by SE, Doctoral College Gallager proposed and developed low density parity check (LDPC) codes in the early 1960s. LDPC codes were rediscovered in the early 1990s and shown to be capacity approaching over the additive white Gaussian noise (AWGN) channel. Subsequently, density evolution (DE) optimized symbol node degree distributions ...

  8. Influence of screw length and diameter on tibial strain energy density distribution after anterior cruciate ligament reconstruction

    Science.gov (United States)

    Yao, Jie; Kuang, Guan-Ming; Wong, Duo Wai-Chi; Niu, Wen-Xin; Zhang, Ming; Fan, Yu-Bo

    2014-04-01

    Postoperative tunnel enlargement has been frequently reported after anterior cruciate ligament (ACL) reconstruction. Interference screw, as a surgical implant in ACL reconstruction, may influence natural loading transmission and contribute to tunnel enlargement. The aims of this study are (1) to quantify the alteration of strain energy den sity (SED) distribution after the anatomic single-bundle ACL reconstruction; and (2) to characterize the influence of screw length and diameter on the degree of the SED alteration. A validated finite element model of human knee joint was used. The screw length ranging from 20 to 30mm with screw diameter ranging from 7 to 9 mm were investigated. In the post-operative knee, the SED increased steeply at the extra-articular tunnel aperture under compressive and complex loadings, whereas the SED decreased beneath the screw shaft and nearby the intra-articular tunnel aperture. Increasing the screw length could lower the SED deprivation in the proximal part of the bone tunnel; whereas increasing either screw length or diameter could aggravate the SED deprivation in the distal part of the bone tunnel. Decreasing the elastic modulus of the screw could lower the bone SED deprivation around the screw. In consideration of both graft stability and SED alteration, a biodegradable interference screw with a long length is recommended, which could provide a beneficial mechanical environment at the distal part of the tunnel, and meanwhile decrease the bone-graft motion and synovial fluid propagation at the proximal part of the tunnel. These findings together with the clinical and histological factors could help to improve surgical outcome, and serve as a preliminary knowledge for the following study of biodegradable interference screw. [Figure not available: see fulltext.

  9. Density and length of stomatal and epidermal cells in "living fossil" trees grown under elevated CO 2 and a polar light regime

    Science.gov (United States)

    Ogaya, R.; Llorens, L.; Peñuelas, J.

    2011-07-01

    During the Cretaceous and early Tertiary, when the climate was warm and the atmospheric CO 2 concentration ([CO 2]) was at least double that of the present-day, polar forests populated high latitude landmasses. We investigated the density and length of stomata and other epidermal cells of two deciduous and three evergreen "living fossil" tree species representative of these ancient forests. These tree species were grown in a simulated Cretaceous high latitude environment at either ambient (400 ppmv) or elevated (800 ppmv) [CO 2] during four years. After 4 years growing at elevated [CO 2], the leaf stomatal density and index (percentage of leaf epidermal cells that are stomata) of these plants were similar to those of their counterparts growing at ambient [CO 2]. While the CO 2 enrichment only modified the stomatal pore length in two of the five studied species, it increased significantly the overall length of the epidermal cells of all the species, reducing their density. These results revealed that leaf epidermal cells of these "living fossil" species were more sensitive than stomata to an experimental doubling of atmospheric CO 2 concentration.

  10. Uncovering genes and ploidy involved in the high diversity in root hair density, length and response to local scarce phosphate in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Markus G Stetter

    Full Text Available Plant root hairs increase the root surface to enhance the uptake of sparingly soluble and immobile nutrients, such as the essential nutrient phosphorus, from the soil. Here, root hair traits and the response to scarce local phosphorus concentration were studied in 166 accessions of Arabidopsis thaliana using split plates. Root hair density and length were correlated, but highly variable among accessions. Surprisingly, the well-known increase in root hair density under low phosphorus was mostly restricted to genotypes that had less and shorter root hairs under P sufficient conditions. By contrast, several accessions with dense and long root hairs even had lower hair density or shorter hairs in local scarce phosphorus. Furthermore, accessions with whole-genome duplications developed more dense but phosphorus-insensitive root hairs. The impact of genome duplication on root hair density was confirmed by comparing tetraploid accessions with their diploid ancestors. Genome-wide association mapping identified candidate genes potentially involved in root hair responses tp scarce local phosphate. Knock-out mutants in identified candidate genes (CYR1, At1g32360 and RLP48 were isolated and differences in root hair traits in the mutants were confirmed. The large diversity in root hair traits among accessions and the diverse response when local phosphorus is scarce is a rich resource for further functional analyses.

  11. Construction of an SNP-based high-density linkage map for flax (Linum usitatissimum L.) using specific length amplified fragment sequencing (SLAF-seq) technology.

    Science.gov (United States)

    Yi, Liuxi; Gao, Fengyun; Siqin, Bateer; Zhou, Yu; Li, Qiang; Zhao, Xiaoqing; Jia, Xiaoyun; Zhang, Hui

    2017-01-01

    Flax is an important crop for oil and fiber, however, no high-density genetic maps have been reported for this species. Specific length amplified fragment sequencing (SLAF-seq) is a high-resolution strategy for large scale de novo discovery and genotyping of single nucleotide polymorphisms. In this study, SLAF-seq was employed to develop SNP markers in an F2 population to construct a high-density genetic map for flax. In total, 196.29 million paired-end reads were obtained. The average sequencing depth was 25.08 in male parent, 32.17 in the female parent, and 9.64 in each F2 progeny. In total, 389,288 polymorphic SLAFs were detected, from which 260,380 polymorphic SNPs were developed. After filtering, 4,638 SNPs were found suitable for genetic map construction. The final genetic map included 4,145 SNP markers on 15 linkage groups and was 2,632.94 cM in length, with an average distance of 0.64 cM between adjacent markers. To our knowledge, this map is the densest SNP-based genetic map for flax. The SNP markers and genetic map reported in here will serve as a foundation for the fine mapping of quantitative trait loci (QTLs), map-based gene cloning and marker assisted selection (MAS) for flax.

  12. Using specific length amplified fragment sequencing to construct the high-density genetic map for Vitis ( Vitis vinifera L. × Vitis amurensis Rupr.

    Directory of Open Access Journals (Sweden)

    yinshan eGuo

    2015-06-01

    Full Text Available In this study, 149 F1 plants from the interspecific cross between ‘Red Globe’ (Vitis vinifera L. and ‘Shuangyou’ (Vitis amurensis Rupr. and the parent were used to construct a molecular genetic linkage map by using the specific length amplified fragment sequencing technique. DNA sequencing generated 41.282 Gb data consisting of 206,411,693 paired-end reads. The average sequencing depths were 68.35 for ‘Red Globe,’ 63.65 for ‘Shuangyou,’ and 8.01 for each progeny. In all, 115,629 high-quality specific length amplified fragments were detected, of which 42,279 were polymorphic. The genetic map was constructed using 7,199 of these polymorphic markers. These polymorphic markers were assigned to 19 linkage groups; the total length of the map was 1929.13 cM, with an average distance of 0.28 cM between each maker. To our knowledge, the genetic maps constructed in this study contain the largest number of molecular markers. These high-density genetic maps might form the basis for the fine quantitative trait loci mapping and molecular-assisted breeding of grape.

  13. Short-length and high-density TiO2 nanorod arrays for the efficient charge separation interface in perovskite solar cells

    International Nuclear Information System (INIS)

    Xiao, Guannan; Shi, Chengwu; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-01-01

    The TiO 2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm −2 were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI 2 ·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH 3 NH 3 I/CH 3 NH 3 Br=85/15. The perovskite solar cells based on the TiO 2 nanorod array and 560 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO 2 nanorod array and with 530 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer gave the best PCE of 12.82% at the relative humidity of 50–54%. - Graphical abstract: The TiO 2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm −2 were prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. The optimal annealing temperature of TiO 2 nanorod arrays was 450 °C. The perovskite solar cells based on the TiO 2 nanorod array and 560 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93% and the average PCE of 13.41±2.52%, while the corresponding planar perovskite solar cells without the TiO 2 nanorod array and with 530 nm-thickness CH 3 NH 3 PbI 3−x Br x absorber layer gave the best PCE of 12.82% and the average PCE of 10.54±2.28% at the relative humidity of 50–54%. - Highlights: • Preparation of TiO 2 nanorod array with length of 70 nm and density of 1000 µm −2 . • Influence of annealing temperatures on the -OH content of Ti

  14. Short-length and high-density TiO{sub 2} nanorod arrays for the efficient charge separation interface in perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Guannan; Shi, Chengwu, E-mail: shicw506@foxmail.com; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-05-15

    The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI{sub 2}·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH{sub 3}NH{sub 3}I/CH{sub 3}NH{sub 3}Br=85/15. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% at the relative humidity of 50–54%. - Graphical abstract: The TiO{sub 2} nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 µm{sup −2} were prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. The optimal annealing temperature of TiO{sub 2} nanorod arrays was 450 °C. The perovskite solar cells based on the TiO{sub 2} nanorod array and 560 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93% and the average PCE of 13.41±2.52%, while the corresponding planar perovskite solar cells without the TiO{sub 2} nanorod array and with 530 nm-thickness CH{sub 3}NH{sub 3}PbI{sub 3−x}Br{sub x} absorber layer gave the best PCE of 12.82% and the average PCE of 10.54±2.28% at the relative humidity of 50–54%. - Highlights:

  15. 'Length'at Length

    Indian Academy of Sciences (India)

    Admin

    He was interested to know how `large' is the set of numbers x for which the series is convergent. Here large refers to its length. But his set is not in the class ♢. Here is another problem discussed by Borel. Consider .... have an infinite collection of pairs of new shoes and want to choose one shoe from each pair. We have an ...

  16. Development of high-polarization Fe/Ge neutron polarizing supermirror: Possibility of fine-tuning of scattering length density in ion beam sputtering

    Science.gov (United States)

    Maruyama, R.; Yamazaki, D.; Akutsu, K.; Hanashima, T.; Miyata, N.; Aoki, H.; Takeda, M.; Soyama, K.

    2018-04-01

    The multilayer structure of Fe/Si and Fe/Ge systems fabricated by ion beam sputtering (IBS) was investigated using X-ray and polarized neutron reflectivity measurements and scanning transmission electron microscopy with energy-dispersive X-ray analysis. The obtained result revealed that the incorporation of sputtering gas particles (Ar) in the Ge layer gives rise to a marked reduction in the neutron scattering length density (SLD) and contributes to the SLD contrast between the Fe and Ge layers almost vanishing for spin-down neutrons. Bundesmann et al. (2015) have shown that the implantation of primary Ar ions backscattered at the target is responsible for the incorporation of Ar particles and that the fraction increases with increasing ion incidence angle and increasing polar emission angle. This leads to a possibility of fine-tuning of the SLD for the IBS, which is required to realize a high polarization efficiency of a neutron polarizing supermirror. Fe/Ge polarizing supermirror with m = 5 fabricated under the same condition showed a spin-up reflectivity of 0.70 at the critical momentum transfer. The polarization was higher than 0.985 for the qz range where the correction for the polarization inefficiencies of the beamline works properly. The result of the polarized neutron reflectivity measurement suggests that the "magnetically-dead" layers formed at both sides of the Fe layer, together with the SLD contrast, play a critical role in determining the polarization performance of a polarizing supermirror.

  17. Density functional theory study of silodithiophene thiophenepyrrolopyrroledion-based small molecules: The effect of alkyl side chain length in electron donor materials

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Dong Kyun; Yeo, Hak; Kwak, Kyung Won [Dept. of Chemistry, Chung-Ang University, Seoul (Korea, Republic of); Yoon, Young Woon; Kim, Bong Soo [Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology, Seoul (Korea, Republic of); Lee, Kyung Koo [Dept. of Chemistry, Kunsan National University, Gunsan (Korea, Republic of)

    2015-02-15

    Push–pull small molecules are promising electron-donor materials for organic solar cells. Thus, precise prediction of their electronic structures is of paramount importance to control the optical and electrical properties of the solar cells. Various types of alkyl chains are usually introduced to increase solubility and modify the morphology of the resulting molecular films. Here, using density functional theory (DFT) and time-dependent DFT (TD-DFT), we report the precise effect of increasing the length of the alkyl chain on the electronic structure of an electron donor molecule 6,60-((4,4-dialkyl-4H-silolo[3,2-b:4,5-b′]-dithiophene-2,6-diyl) bis(thiophene-5,2-diyl))bis(2,5-alkyl-3-(thiophen-2-yl) -2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (DTS1TDPP). Alkyl groups were attached to the bridging position (silicon atom) of the fused rings and nitrogen atom of the pyrrolopyrroledione groups. We demonstrate that the alkyl groups do not perturb the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, π-delocalized backbone structure, and UV–Vis absorption spectrum when they are placed at the least steric effect positions.

  18. Short-length and high-density TiO2 nanorod arrays for the efficient charge separation interface in perovskite solar cells

    Science.gov (United States)

    Xiao, Guannan; Shi, Chengwu; Zhang, Zhengguo; Li, Nannan; Li, Long

    2017-05-01

    The TiO2 nanorod arrays with the length of 70 nm, the diameter of 20 nm, and the areal density of 1000 μm-2 were firstly prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 60 min. Over-500 nm-thickness CH3NH3PbI3-xBrx absorber layers were successfully obtained by sequential deposition routes using 1.7 M PbI2·DMSO complex precursor solution and 0.465 M isopropanol solution of the methylammonium halide mixture with the molar ratio of CH3NH3I/CH3NH3Br=85/15. The perovskite solar cells based on the TiO2 nanorod array and 560 nm-thickness CH3NH3PbI3-xBrx absorber layer exhibited the best photoelectric conversion efficiency (PCE) of 15.93%, while the corresponding planar perovskite solar cells without the TiO2 nanorod array and with 530 nm-thickness CH3NH3PbI3-xBrx absorber layer gave the best PCE of 12.82% at the relative humidity of 50-54%.

  19. Fundamental length and relativistic length

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1988-01-01

    It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem

  20. 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...

  1. Effect of Different Rearing Density on Survival Rate and Growth of Giant Gouramy Osphronemus gouramy Lac. Fry at Size of 2 cm in Length

    Directory of Open Access Journals (Sweden)

    I. Effendi

    2007-07-01

    Full Text Available Giant gouramy Osphronemus gouramy Lac is one of the fish for food that has high economic value, but its production is not  met with the market demand yet.  The effort is needed to be done in order to increase production of giant gouramy fry by an intensive hatchery system through high rearing density.  This study was performed to determine the effect of rearing density on survival rate and growth of fry.  Fry were reared in aquaria 60x29x33 cm filled with 35 liters water, and fed by Tubifex at satiation as much as  0.23-0.28 g/fry/day with feeding frequency  2 times a day.   Collected  data were survival rate, growth, feed consumption, feed efficiency, and water quality.  The result of study showed that survival rate and feed efficiency did not affected by rearing density, while growth and feed quantity were did.  Survival rate of fish was high; 90.14-99.52%.  Growth and feed consumption were decreased by increasing of  rearing density. Keywords: giant gouramy, Osphronemus gouramy, rearing density, growth   ABSTRAK Ikan gurame, Osphronemus gouramy Lac. merupakan salah satu jenis ikan konsumsi yang memiliki nilai ekonomi yang cukup tinggi, tetapi hasil produksinya masih belum dapat memenuhi permintaan pasar. Upaya perlu dilakukan untuk meningkatkan produksi benih ikan gurame dengan pembenihan secara intensif melalui peningkatan padat penebaran. Penelitian ini dilakukan untuk mengetahui pengaruh padat penebaran terhadap kelangsungan hidup dan pertumbuhan benih ikan gurami. Benih ikan gurami dipelihara pada akuarium berukuran 60×29×33 cm3 yang diisi air sebanyak 35 liter. Pakan berupa cacing sutera diberikan secara at satiation sebanyak 0,23 - 0,28 g/ekor/hari dengan frekuensi 2 kali/hari. Data yang diambil meliputi kelangsungan hidup, pertumbuhan, jumlah pakan yang dikonsumsi, efisiensi pakan dan kualitas air.  Hasil penelitian menunjukkan bahwa padat penebaran tidak mempengaruhi kelangsungan hidup dan efisiensi pakan, namun

  2. Optical mode engineering and high power density per facet length (>8.4 kW/cm) in tilted wave laser diodes

    Science.gov (United States)

    Ledentsov, N. N.; Shchukin, V. A.; Maximov, M. V.; Gordeev, N. Y.; Kaluzhniy, N. A.; Mintairov, S. A.; Payusov, A. S.; Shernyakov, Yu. M.

    2016-03-01

    Tilted Wave Lasers (TWLs) based on optically coupled thin active waveguide and thick passive waveguide offer an ultimate solution for thick-waveguide diode laser, preventing catastrophic optical mirror damage and thermal smile in laser bars, providing robust operation in external cavity modules thus enabling wavelength division multiplexing and further increase in brightness enabling direct applications of laser diodes in the mainstream material processing. We show that by proper engineering of the waveguide one can realize high performance laser diodes at different tilt angles of the vertical lobes. Two vertical lobes directed at various angles (namely, +/-27° or +/-9°) to the junction plane are experimentally realized by adjusting the compositions and the thicknesses of the active and the passive waveguide sections. The vertical far field of a TWL with the two +/-9° vertical beams allows above 95% of all the power to be concentrated within a vertical angle below 25°, the fact which is important for laser stack applications using conventional optical coupling schemes. The full width at half maximum of each beam of the value of 1.7° evidences diffraction- limited operation. The broad area (50 μm) TWL chips at the cavity length of 1.5 mm reveal a high differential efficiency ~90% and a current-source limited pulsed power >42W for as-cleaved TWL device. Thus the power per facet length in a laser bar in excess of 8.4 kW/cm can be realized. Further, an ultimate solution for the smallest tilt angle is that where the two vertical lobes merge forming a single lobe directed at the zero angle is proposed.

  3. Common Genetic Variation in the DKK1 Gene is Associated with Hip Axis Length but not with Bone Mineral Density and Bone Turnover Markers in Young Adult Men: Results from the Odense Androgen Study

    DEFF Research Database (Denmark)

    Piters, Elke; Balemans, Wendy; Nielsen, Torben Leo

    2010-01-01

    LRP5 was recently confirmed as an important susceptibility gene for osteoporosis. Our objective was to evaluate the effect of DKK1 polymorphisms on bone mineral density (BMD), hip geometry, and bone turnover. DKK1 is a secreted protein that binds to LRP5/6 receptors and inhibits canonical Wnt...... with hip axis length (HAL), independent of BMD and height. Moreover, the association seemed to be driven by the nonsedentary subgroup (P = 0.004). Haplotype analysis further confirmed the association of rs1569198 with HAL. Furthermore, we obtained indications for interaction between DKK1 and LRP5 genotypes...

  4. Fundamental length

    International Nuclear Information System (INIS)

    Pradhan, T.

    1975-01-01

    The concept of fundamental length was first put forward by Heisenberg from purely dimensional reasons. From a study of the observed masses of the elementary particles known at that time, it is sumrised that this length should be of the order of magnitude 1 approximately 10 -13 cm. It was Heisenberg's belief that introduction of such a fundamental length would eliminate the divergence difficulties from relativistic quantum field theory by cutting off the high energy regions of the 'proper fields'. Since the divergence difficulties arise primarily due to infinite number of degrees of freedom, one simple remedy would be the introduction of a principle that limits these degrees of freedom by removing the effectiveness of the waves with a frequency exceeding a certain limit without destroying the relativistic invariance of the theory. The principle can be stated as follows: It is in principle impossible to invent an experiment of any kind that will permit a distintion between the positions of two particles at rest, the distance between which is below a certain limit. A more elegant way of introducing fundamental length into quantum theory is through commutation relations between two position operators. In quantum field theory such as quantum electrodynamics, it can be introduced through the commutation relation between two interpolating photon fields (vector potentials). (K.B.)

  5. Bond length and electric current oscillation of long linear carbon chains: Density functional theory, MpB model, and quantum spin transport studies

    International Nuclear Information System (INIS)

    Oeiras, R. Y.; Silva, E. Z. da

    2014-01-01

    Carbon linear atomic chains attached to graphene have experimentally been produced. Motivated by these results, we study the nature of the carbon bonds in these nanowires and how it affects their electrical properties. In the present study we investigate chains with different numbers of atoms and we observe that nanowires with odd number of atoms present a distinct behavior than the ones with even numbers. Using graphene nanoribbons as leads, we identify differences in the quantum transport of the chains with the consequence that even and odd numbered chains have low and high electrical conduction, respectively. We also noted a dependence of current with the wire size. We study this unexpected behavior using a combination of first principles calculations and simple models based on chemical bond theory. From our studies, the electrons of carbon nanowires present a quasi-free electron behavior and this explains qualitatively the high electrical conduction and the bond lengths with unexpected values for the case of odd nanowires. Our study also allows the understanding of the electric conduction dependence with the number of atoms and their parity in the chain. In the case of odd number chains a proposed π-bond (MpB) model describes unsaturated carbons that introduce a mobile π-bond that changes dramatically the structure and transport properties of these wires. Our results indicate that the nature of bonds plays the main role in the oscillation of quantum electrical conduction for chains with even and odd number of atoms and also that nanowires bonded to graphene nanoribbons behave as a quasi-free electron system, suggesting that this behavior is general and it could also remain if the chains are bonded to other materials

  6. Effects of exposure to moderate levels of ethanol during prenatal brain development on dendritic length, branching, and spine density in the nucleus accumbens and dorsal striatum of adult rats.

    Science.gov (United States)

    Rice, James P; Suggs, Lisa E; Lusk, Alexandra V; Parker, Matthew O; Candelaria-Cook, Felicha T; Akers, Katherine G; Savage, Daniel D; Hamilton, Derek A

    2012-09-01

    Reductions in measures of dendritic morphology in the agranular insular cortex have been identified as consequences of prenatal exposure to moderate levels of ethanol in the rat. Motivated by the strong connectivity between this region of frontal cortex and the striatum and a growing body of data linking specific components of the mesocortical/limbic system to effects of ethanol and ethanol self-administration, the current study investigated the effects of moderate fetal ethanol exposure on the dendritic morphology of medium spiny neurons (MSNs) in several regions of the striatum. Throughout gestation, pregnant rat dams either consumed a saccharin solution (control) or achieved average daily blood ethanol concentrations of 84 mg% via voluntary consumption of a 5% ethanol solution. The brains of adult male offspring were extracted and processed for Golgi-Cox staining. MSNs from the dorsomedial striatum, dorsolateral striatum and the nucleus accumbens core and shell were sampled for analysis. Relative to saccharin controls, robust reductions in dendritic length and branching, but not spine density, were observed in the shell of the nucleus accumbens in fetal-ethanol-exposed rats. No significant prenatal ethanol effects were found in the other regions of the striatum. These findings suggest that exposure to moderate levels of ethanol in utero can have profound effects on brain regions related to reward processing and provide possible clues relevant to understanding increased self-administration of drugs of abuse in animals exposed to ethanol during brain development. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Field performance of Solanum sisymbriifolium, a trap crop for potato cyst nematodes. II. Root characteristics

    NARCIS (Netherlands)

    Timmermans, B.G.H.; Vos, J.; Stomph, T.J.; Nieuwburg, van J.G.W.; Putten, van der P.E.L.

    2007-01-01

    Hatching of potato cyst nematodes is induced by root exudates of Solanaceae, such as Solanum sisymbriifolium, and is therefore related to root length distribution of this crop. A mathematical model was derived to relate the hatching potential to root length density (RLD). A series of field

  8. Mixed and monospecific stands of eucalyptus and black-wattle: I - fine root length density Plantios monoespecíficos e mistos de eucalipto e acácia-negra: I - densidade do comprimento de raízes finas

    Directory of Open Access Journals (Sweden)

    Márcio Viera

    2012-10-01

    Full Text Available Fine root length density (FRLD was evaluated in mixed and monospecific stands of Eucalyptus grandis x E. urophylla and Acacia mearnsii in Southern Brazil. FRLD (≤2,0mm at 8 and 18 months after planting in the treatments: 100E (100% of eucalyptus; 100A (100% of Acacia mearnsii; 50E:50A (50% of eucalyptus + 50% of Acacia mearnsii. The findings demonstrated that the FRLD at 8 months of age have the same distribution, in the two different species, in the distribution of the different soil layers, reaching the maximum projection of 125cm from the tree trunk. For the age of 18 months after planting, it was verified that the FRLD in the monospecific stand of Acacia mearnsii was higher than in the monoculture and mixed stand of Eucalyptus grandis x E. urophylla. Therefore, no interaction, neither positive nor negative, between the root systems of Eucalyptus grandis x E. urophylla and Acacia mearnsii during the 18 months after planting was found. The higher FRLD is found at the soil layers surface, next to the tree trunk and in the planting line, followed by the diagonal and planting rows. The initial growth in length of the root system of Acacia mearnsii is more dynamic with higher density than the eucalyptus, but without interfering directly in the global growth of fine roots in mixed stands.Avaliou-se a densidade do comprimento de raízes finas (DCRF de plantios monoespecíficos e misto de Eucalyptus grandis x E. urophylla e de Acacia mearnsii na região sul do Brasil. A DCRF (≤2,0mm foi determinada aos 8 e 18 meses após o plantio nos tratamentos: 100E (100% de eucalipto; 100A (100% de Acacia mearnsii; 50E:50A (50% de eucalipto + 50% de Acacia mearnsii. A DCRF aos oito meses de idade possui o mesmo comportamento para a ocupação das diferentes camadas do solo, atingindo uma projeção máxima de 125cm de distância em relação ao tronco da árvore. Já, aos 18 meses após o plantio, verificou-se que, no cultivo monoespecífico de Acacia

  9. Effects of irrigation strategies and soils on field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Plauborg, Finn; Andersen, Mathias Neumann

    2011-01-01

    Root distribution of field grown potatoes (cv. Folva) was studied in 4.32 m2 lysimeters and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. Drip irrigation was applied for all irrigations. Irrigations were run in three different soils: coarse sand......, loamy sand, and sandy loam. Irrigation treatments started after tuber bulking and lasted until final harvest with PRD and DI receiving 65% of FI. Potatoes irrigated with water-saving irrigation techniques (PRD and DI) did not show statistically different dry root mass and root length density (RLD, cm...... root per cm3 soil) compared with root development in fully irrigated (FI) potatoes. Highest RLD existed in the top 30–40 cm of the ridge below which it decreased sharply. The RLD was distributed homogenously along the ridge and furrow but heterogeneously across the ridge and furrow with highest root...

  10. Den Europeiska unionen i en globaliserande värld

    DEFF Research Database (Denmark)

    Manners, Ian James

    2013-01-01

    faktor för att förstå regionala ansträngningar att samordna olika ekonomiska, sociala, miljömässiga och politiska förändringar. Regionalt integrationsarbete och globaliseringen av livsstilar har tillsammans blivit del av den centrala dynamiken i förbindelserna mellan EU och världen. Som Julia Kristeva...

  11. Telomere length analysis.

    Science.gov (United States)

    Canela, Andrés; Klatt, Peter; Blasco, María A

    2007-01-01

    Most somatic cells of long-lived species undergo telomere shortening throughout life. Critically short telomeres trigger loss of cell viability in tissues, which has been related to alteration of tissue function and loss of regenerative capabilities in aging and aging-related diseases. Hence, telomere length is an important biomarker for aging and can be used in the prognosis of aging diseases. These facts highlight the importance of developing methods for telomere length determination that can be employed to evaluate telomere length during the human aging process. Telomere length quantification methods have improved greatly in accuracy and sensitivity since the development of the conventional telomeric Southern blot. Here, we describe the different methodologies recently developed for telomere length quantification, as well as their potential applications for human aging studies.

  12. Influence of shrub cover vegetal and slope length on soil bulk density; Influencia de la cubierta vegetal arbustiva y la longitud de la ladera sobre la densidad aparente del suelo

    Energy Technology Data Exchange (ETDEWEB)

    Bienes, R.; Jimenez, R.; Ruiz, M.; Garcia-Estringana, P.; Marques, M. J.

    2009-07-01

    In arid and semiarid environments of the Mediterranean climate, the shrub species play an important role in the revegetation of abandoned lands, which enables to control the soil losses, organic material and water. In this article are compared the results obtained under different revegetation in abandoned lands in the central area of Spain. In these revegetation has been used two native shrubs: A triplex halimus (Ah) and Retama sphaerocarpa (Rs), and were analyzed the influence of these revegetation in the contents of organic material of soil and apparent density in 5 years time after planting. As control, have been considered the pieces of ground with spontaneous vegetation abandoned in the same date that the shrubs revegetation. Atriplex halimus gives to the soil a covering capable to intercept a big amount of water drops absorbing a great amount part of the kinetic energy of the rain, while provides a microclimates as a result of be able to soften the wind, the temperature and the evaporation-transpiration, which makes it efficient to control the erosion and the desertification (Le Houerou, 2000). Retama sphaerocarpa was chosen because it is a native shrub very characteristic, and, due to its symbiosis with the Bradyrhizobium, enriches the soil in nitrogen, which is taken by the nitrophilous species enhancing the spontaneous vegetal covering. (Author) 9 refs.

  13. Fluid mixing in stratified gravity currents: the Prandtl mixing length.

    Science.gov (United States)

    Odier, P; Chen, J; Rivera, M K; Ecke, R E

    2009-04-03

    Shear-induced vertical mixing in a stratified flow is a key ingredient of thermohaline circulation. We experimentally determine the vertical flux of momentum and density of a forced gravity current using high-resolution velocity and density measurements. A constant eddy-viscosity model provides a poor description of the physics of mixing, but a Prandtl mixing length model relating momentum and density fluxes to mean velocity and density gradients works well. For the average gradient Richardson number Ri(g) approximately 0.08 and a Taylor Reynolds number Re(lambda) approximately 100, the mixing lengths are fairly constant, about the same magnitude, comparable to the turbulent shear length.

  14. Telomere length and depression

    DEFF Research Database (Denmark)

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

    2017-01-01

    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...

  15. 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.

  16. Upper Extremity Length Equalization

    OpenAIRE

    DeCoster, Thomas A.; Ritterbusch, John; Crawford, Mark

    1992-01-01

    Significant upper extremity length inequality is uncommon but can cause major functional problems. The ability to position and use the hand may be impaired by shortness of any of the long bones of the upper extremity. In many respects upper and lower extremity length problems are similar. They most commonly occur after injury to a growing bone and the treatment modalities utilized in the lower extremity may be applied to the upper extremity. These treatment options include epiphysiodesis, sho...

  17. Relativistic Length Agony Continued

    Science.gov (United States)

    Redzic, D. V.

    2014-06-01

    We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redzic 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.

  18. Telomere Length and Mortality

    DEFF Research Database (Denmark)

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

    2008-01-01

    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...... 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...

  19. Full Length Research Article

    African Journals Online (AJOL)

    Administrator

    Out of the 320 male sheep examined, 87(27.2%) were infected, while 9(19.1%) of the 47 females examined were infected (Table 2). Infection varied from one abattoir to another. Age related distribution of P. cervi is shown in Table 3. Out of 356 adult sheep (>2yrs) examined, 35. Full Length Research Article. 12 ...

  20. Mixing lengths scaling in a gravity flow

    Energy Technology Data Exchange (ETDEWEB)

    Ecke, Robert E [Los Alamos National Laboratory; Rivera, Micheal [Los Alamos National Laboratory; Chen, Jun [Los Alamos National Laboratory; Ecke, Robert E [Los Alamos National Laboratory

    2009-01-01

    We present an experimental study of the mixing processes in a gravity current. The turbulent transport of momentum and buoyancy can be described in a very direct and compact form by a Prandtl mixing length model [1]: the turbulent vertical fluxes of momentum and buoyancy are found to scale quadraticatly with the vertical mean gradients of velocity and density. The scaling coefficient is the square of the mixing length, approximately constant over the mixing zone of the stratified shear layer. We show in this paper how, in different flow configurations, this length can be related to the shear length of the flow {radical}({var_epsilon}/{partial_derivative}{sub z}u{sup 3}).

  1. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  2. Length of excitable knots

    Science.gov (United States)

    Maucher, Fabian; Sutcliffe, Paul

    2017-07-01

    In this paper, we present extensive numerical simulations of an excitable medium to study the long-term dynamics of knotted vortex strings for all torus knots up to crossing number 11. We demonstrate that FitzHugh-Nagumo evolution preserves the knot topology for all the examples presented, thereby providing a field theory approach to the study of knots. Furthermore, the evolution yields a well-defined minimal length for each knot that is comparable to the ropelength of ideal knots. We highlight the role of the medium boundary in stabilizing the length of the knot and discuss the implications beyond torus knots. We also show that there is not a unique attractor within a given knot topology.

  3. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  4. Length-weight and length-length relationships of freshwater wild ...

    African Journals Online (AJOL)

    Length-weight and length-length relationships of freshwater wild catfish Mystus bleekeri from Nala Daik, Sialkot, Pakistan. ... Linear regression analysis was used, first to compute the degree of relationship between length and weight and then among total (TL), standard (SL) and fork lengths (FL). LWR exhibited a highly ...

  5. 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

  6. Short cervical length dilemma.

    Science.gov (United States)

    Suhag, Anju; Berghella, Vincenzo

    2015-06-01

    Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. With research efforts, the rate of PTB decreased to 11.4% in 2013. Transvaginal ultrasound (TVU) cervical length (CL) screening predicts PTB. In asymptomatic singletons without prior spontaneous PTB (sPTB), TVU CL screening should be done. If the cervix is 20 mm or less, vaginal progesterone is indicated. In asymptomatic singletons with prior sPTB, serial CL screening is indicated. In multiple gestations, routine cervical screening is not indicated. In symptomatic women with preterm labor, TVU CL screening and fetal fibronectin testing is recommended. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. 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.

  8. Primary length standard adjustment

    Science.gov (United States)

    Ševčík, Robert; Guttenová, Jana

    2007-04-01

    This paper deals with problems and techniques connected with primary length standard adjusting, which includes disassembling of the device and by use of the secondary laser with collimated beam and diffraction laws successively reassembling of the laser. In the reassembling process the device was enhanced with substituting the thermal grease cooling of cold finger by copper socket cooler. This improved external cooling system enables more effective cooling of molecular iodine in the cell, which allows better pressure stability of iodine vapor and easier readjustment of the system.

  9. Density functional theory and multiscale materials modeling

    Indian Academy of Sciences (India)

    In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related density functions has been found to be quite appropriate. A unique single unified theoretical framework that emerges through the density concept at these ...

  10. Road density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  11. Information-theoretic lengths of Jacobi polynomials

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, A; Dehesa, J S [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Granada, Granada (Spain); Sanchez-Moreno, P, E-mail: agmartinez@ugr.e, E-mail: pablos@ugr.e, E-mail: dehesa@ugr.e [Instituto ' Carlos I' de Fisica Teorica y Computacional, Universidad de Granada, Granada (Spain)

    2010-07-30

    The information-theoretic lengths of the Jacobi polynomials P{sup ({alpha}, {beta})}{sub n}(x), which are information-theoretic measures (Renyi, Shannon and Fisher) of their associated Rakhmanov probability density, are investigated. They quantify the spreading of the polynomials along the orthogonality interval [- 1, 1] in a complementary but different way as the root-mean-square or standard deviation because, contrary to this measure, they do not refer to any specific point of the interval. The explicit expressions of the Fisher length are given. The Renyi lengths are found by the use of the combinatorial multivariable Bell polynomials in terms of the polynomial degree n and the parameters ({alpha}, {beta}). The Shannon length, which cannot be exactly calculated because of its logarithmic functional form, is bounded from below by using sharp upper bounds to general densities on [- 1, +1] given in terms of various expectation values; moreover, its asymptotics is also pointed out. Finally, several computational issues relative to these three quantities are carefully analyzed.

  12. Lung density

    DEFF Research Database (Denmark)

    Garnett, E S; Webber, C E; Coates, G

    1977-01-01

    The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...

  13. Density functional theory and multiscale materials modeling

    Indian Academy of Sciences (India)

    One of the vital ingredients in the theoretical tools useful in materials modeling at all the length scales of interest is the concept of density. In the microscopic length scale, it is the electron density that has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids.

  14. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    This document deals with correlation length of electrostatic turbulence. First, the model of drift waves turbulence is presented. Then, the radial correlation length is determined analytically with toroidal coupling and non linear coupling. (TEC). 5 refs

  15. Finite length thermal equilibria of a pure electron plasma column

    International Nuclear Information System (INIS)

    Prasad, S.A.; O'Neil, T.M.

    1979-01-01

    The electrons of a pure electron plasma may be in thermal equilibrium with each other and still be confined by static magnetic and electric fields. Since the electrons make a significant contribution to the electric field, only certain density profiles are consistent with Poisson's equation. The class of such distributions for a finite length cylindrical column is investigated. In the limit where the Debye length is small compared with the dimensions of the column, the density is essentially constant out to some surface of revolution and then falls off abruptly. The falloff in density is a universal function when measured along the local normal to the surface of revolution and scaled in terms of the Debye length. The solution for the shape of the surface of revolution is simplified by passage to the limit of zero Debye length

  16. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    In this paper, the radial correlation length of an electrostatic drift wave turbulence is analytically determined in various regimes. The analysis relies on the calculation of a range of mode non linear interaction, which is an instantaneous correlation length. The link with the usual correlation length has not been investigated yet. (TEC). 5 refs

  17. 7 Length-weight relationship

    African Journals Online (AJOL)

    Administrator

    Length-weight measurements were taken from well-preserved fish specimens from which stomachs were extracted for the analysis of the food contents, using frequency of occurrence, numerical and gravimetric methods, as well as index of relative importance. The length-frequency analysis showed a size distribution with a ...

  18. Comparison of fiber length analyzers

    Science.gov (United States)

    Don Guay; Nancy Ross Sutherland; Walter Rantanen; Nicole Malandri; Aimee Stephens; Kathleen Mattingly; Matt Schneider

    2005-01-01

    In recent years, several fiber new fiber length analyzers have been developed and brought to market. The new instruments provide faster measurements and the capability of both laboratory and on-line analysis. Do the various fiber analyzers provide the same length, coarseness, width, and fines measurements for a given fiber sample? This paper provides a comparison of...

  19. Spin-Charge Separation in Finite Length Metallic Carbon Nanotubes

    KAUST Repository

    Zhang, Yongyou

    2017-10-17

    Using time-dependent density functional theory, we study the optical excitations in finite length carbon nanotubes. Evidence of spin-charge separation is given in the spacetime domain. We demonstrate that the charge density wave is due to collective excitations of electron singlets, while the accompanying spin density wave is due to those of electron triplets. The Tomonaga–Luttinger liquid parameter and density–density interaction are extrapolated from the first-principles excitation energies. We show that the density–density interaction increases with the length of the nanotube. The singlet and triplet excitation energies, on the other hand, decrease for increasing length of the nanotube. Their ratio is used to establish a first-principles approach for deriving the Tomonaga–Luttinger parameter (in excellent agreement with experimental data). Time evolution analysis of the charge and spin line densities evidences that the charge and spin density waves are elementary excitations of metallic carbon nanotubes. Their dynamics show no dependence on each other.

  20. Low Bone Density

    Science.gov (United States)

    ... Bone Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone ... to people with normal bone density. Detecting Low Bone Density A bone density test will determine whether ...

  1. Electron plasma oscillations at arbitrary Debye lengths

    International Nuclear Information System (INIS)

    Lehnert, B.

    1990-12-01

    A solution is presented for electron plasma oscillation in a thermalized homogeneous plasma, at arbitrary ratios between the Debye length λ D and the perturbation wave length λ. The limit λ D D >> λ corresponds to the free-streaming limit of strong kinetic phase-mixing due to large particle excursions. A strong large Debye distance (LDD) effect already appears when λ D > approx λ. The initial amplitude of the fluid-like contribution to the macroscopic density perturbation then becomes small as compared to the contribution from the free-streaming part. As a consequence, only a small fraction of the density perturbation remains after a limited number of kinetic damping times of the free-streaming part. The analysis further shows that a representation in terms of normal model of the form exp(-iωt) leads to amplitude factors of these modes which are related to each other and which depend on the combined free-streaming and fluid behaviour of the plasma. Consequently, these modes are coupled and cannot be treated as being independent of each other. (au)

  2. [Effects of thinning on fine-root morphology, biomass and N concentration of different branch orders of Chinese fir].

    Science.gov (United States)

    Wang, Zu-Hua; Li, Rui-Xia; Guan, Qing-Wei

    2013-06-01

    Taking a 25-year old Chinese fir (Cunninghamia lanceolata) plantation as the object, this paper studied the effects of thinning on the biomass, morphological traits, and nitrogen concentration of the first five orders roots. With the increase of root order (from the first to the fifth order), there was a significant increase in the fine-root biomass, diameter, and tissue density, and a significantly decrease in the specific root length (SRL), root length density (RLD), and root number (RN). Thinning increased the biomass, RLD, and RN of the first and second orders roots as well as the tissue density of the first, third, fourth, and fifth orders roots significantly, but had no effects on the SRL and nitrogen concentration of each order root. In contrast, thinning decreased the diameter of the first, third, and fourth orders roots significantly. The diameter of the second order roots was obviously smaller in surface (0-10 cm) soil than in subsurface (10-20 cm) soil, while the RLD of the first three orders roots and the RN and nitrogen concentration of the first two orders roots were larger in surface soil than in subsurface soil. The interaction of thinning and soil layer only decreased the diameter of the first two orders roots. It was suggested that the fine-root biomass and morphological traits of Chinese fir were closely related to the vegetation growth and regeneration after thinning.

  3. A pedagogical look at Jeans' density scale

    International Nuclear Information System (INIS)

    Chu, K-H W

    2007-01-01

    We illustrate the derivations of Jeans' criteria for the gravitational instabilities in a static homogeneous Newtonian system for pedagogical objectives. The critical Jeans density surface is presented in terms of dimensionless sound speeds and (characteristic) length scales

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

    DEFF Research Database (Denmark)

    Bjørk, Rasmus

    2011-01-01

    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 poss...

  5. 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.

  6. Continuously variable focal length lens

    Science.gov (United States)

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  7. Overview of bunch length measurements

    International Nuclear Information System (INIS)

    Lumpkin, A. H.

    1999-01-01

    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

  8. Kondo length in bosonic lattices

    Science.gov (United States)

    Giuliano, Domenico; Sodano, Pasquale; Trombettoni, Andrea

    2017-09-01

    Motivated by the fact that the low-energy properties of the Kondo model can be effectively simulated in spin chains, we study the realization of the effect with bond impurities in ultracold bosonic lattices at half filling. After presenting a discussion of the effective theory and of the mapping of the bosonic chain onto a lattice spin Hamiltonian, we provide estimates for the Kondo length as a function of the parameters of the bosonic model. We point out that the Kondo length can be extracted from the integrated real-space correlation functions, which are experimentally accessible quantities in experiments with cold atoms.

  9. Density games.

    Science.gov (United States)

    Novak, Sebastian; Chatterjee, Krishnendu; Nowak, Martin A

    2013-10-07

    The basic idea of evolutionary game theory is that payoff determines reproductive rate. Successful individuals have a higher payoff and produce more offspring. But in evolutionary and ecological situations there is not only reproductive rate but also carrying capacity. Individuals may differ in their exposure to density limiting effects. Here we explore an alternative approach to evolutionary game theory by assuming that the payoff from the game determines the carrying capacity of individual phenotypes. Successful strategies are less affected by density limitation (crowding) and reach higher equilibrium abundance. We demonstrate similarities and differences between our framework and the standard replicator equation. Our equation is defined on the positive orthant, instead of the simplex, but has the same equilibrium points as the replicator equation. Linear stability analysis produces the classical conditions for asymptotic stability of pure strategies, but the stability properties of internal equilibria can differ in the two frameworks. For example, in a two-strategy game with an internal equilibrium that is always stable under the replicator equation, the corresponding equilibrium can be unstable in the new framework resulting in a limit cycle. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Measurement of the diffusion length of thermal neutrons inside graphite

    International Nuclear Information System (INIS)

    Ertaud, A.; Beauge, R.; Fauquez, H.; De Laboulay, H.; Mercier, C.; Vautrey, L.

    1948-11-01

    The diffusion length of thermal neutrons inside a given industrial graphite is determined by measuring the neutron density inside a parallelepipedal piling up of graphite bricks (2.10 x 2.10 x 2.442 m). A 3.8 curies (Ra α → Be) source is placed inside the parallelepipedal block of graphite and thin manganese detectors are used. Corrections are added to the unweighted measurements to take into account the effects of the damping of supra-thermal neutrons in the measurement area. These corrections are experimentally deduced from the differential measurements made with a cadmium screen interposed between the source and the first plane of measurement. An error analysis completes the report. The diffusion length obtained is: L = 45.7 cm ± 0.3. The average density of the graphite used is 1.76 and the average apparent density of the piling up is 1.71. (J.S.)

  11. Cyclic codes of length 2

    Indian Academy of Sciences (India)

    Springer Verlag Heidelberg #4 2048 1996 Dec 15 10:16:45

    [X]/〈X2m. − 1〉 are given. Cyclic codes of length 2m over the finite field Fq, of odd characteristic, are defined in terms of their generator polynomials. The exact minimum distance and the dimension of the codes are obtained. Keywords.

  12. Diet, nutrition and telomere length.

    Science.gov (United States)

    Paul, Ligi

    2011-10-01

    The ends of human chromosomes are protected by DNA-protein complexes termed telomeres, which prevent the chromosomes from fusing with each other and from being recognized as a double-strand break by DNA repair proteins. Due to the incomplete replication of linear chromosomes by DNA polymerase, telomeric DNA shortens with repeated cell divisions until the telomeres reach a critical length, at which point the cells enter senescence. Telomere length is an indicator of biological aging, and dysfunction of telomeres is linked to age-related pathologies like cardiovascular disease, Parkinson disease, Alzheimer disease and cancer. Telomere length has been shown to be positively associated with nutritional status in human and animal studies. Various nutrients influence telomere length potentially through mechanisms that reflect their role in cellular functions including inflammation, oxidative stress, DNA integrity, DNA methylation and activity of telomerase, the enzyme that adds the telomeric repeats to the ends of the newly synthesized DNA. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. 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.

  14. Femur length and biparietal diameter

    African Journals Online (AJOL)

    2014-12-02

    Dec 2, 2014 ... Shipp TD, Bromley B, Mascola M, Benacerraf B. Variation in fetal femur length with respect to maternal race. J Ultrasound Med 2001;20:141‑4. 25. Deter RL, Harrist RB, Birnholz JC, Hadlock FP. Quantitative Obstetrical. Ultrasonography. New York: Wiley; 1986. 26. Yeh MN, Bracero L, Reilly KB, Murtha L, ...

  15. The Distribution of Lightning Channel Lengths in Northern Alabama Thunderstorms

    Science.gov (United States)

    Peterson, H. S.; Koshak, W. J.

    2010-01-01

    Lightning is well known to be a major source of tropospheric NOx, and in most cases is the dominant natural source (Huntreiser et al 1998, Jourdain and Hauglustaine 2001). Production of NOx by a segment of a lightning channel is a function of channel segment energy density and channel segment altitude. A first estimate of NOx production by a lightning flash can be found by multiplying production per segment [typically 104 J/m; Hill (1979)] by the total length of the flash s channel. The purpose of this study is to determine average channel length for lightning flashes near NALMA in 2008, and to compare average channel length of ground flashes to the average channel length of cloud flashes.

  16. 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.

  17. 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.

  18. Keeping disease at arm's length

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    2015-01-01

    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......Many older people live with a range of chronic diseases. However, these diseases do not necessarily impede an active lifestyle. In this article the author analyses the relation between the active ageing discourse and the way older people at two Danish activity centres handle disease. How does...... 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...

  19. Critical length scales for flow phenomena in liquid metal batteries

    Science.gov (United States)

    Kelley, Douglas; Weier, Tom

    2017-11-01

    Liquid metal batteries, a new technology for grid-scale energy storage, are composed of three liquid layers and therefore subject to a wide variety of fluid dynamical phenomena, both beneficial and detrimental. Some, like thermal convection and electrovortex flow, drive finite flow regardless of the size, current density, and temperature of the battery. Others, like the Tayler instability and the metal pad instability, occur only in certain parameter regimes - almost always dependent on length scale. I will discuss critical length scales, considering implications for battery design in light of fundamental fluid dynamics. This work was supported by the National Science Foundation under Award Number CBET-1552182.

  20. Reinvestigation on mixing length in an open channel turbulent flow

    Science.gov (United States)

    Kundu, Snehasis; Kumbhakar, Manotosh; Ghoshal, Koeli

    2018-02-01

    The present study proposes a model on vertical distribution of streamwise velocity in an open channel turbulent flow through a newly proposed mixing length, which is derived for both clear water and sediment-laden turbulent flows. The analysis is based on a theoretical consideration which explores the effect of density stratification on the streamwise velocity profile. The derivation of mixing length makes use of the diffusion equation where both the sediment diffusivity and momentum diffusivity are taken as a function of height from the channel bed. The damping factor present in the mixing length of sediment-fluid mixture contains velocity and concentration gradients. This factor is capable of describing the dip-phenomenon of velocity distribution. From the existing experimental data of velocity, the mixing length data are calculated. The pattern shows that mixing length increases from bed to the dip-position, having a larger value at dip-position and then decreases up to the water surface with a zero value thereat. The present model agrees well with these data sets and this behavior cannot be described by any other existing model. Finally, the proposed mixing length model is applied to find the velocity distribution in wide and narrow open channels. The derived velocity distribution is compared with laboratory channel data of velocity, and the comparison shows good agreement.

  1. 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.

  2. Adaptive treatment-length optimization in spatiobiologically integrated radiotherapy

    Science.gov (United States)

    Ajdari, Ali; Ghate, Archis; Kim, Minsun

    2018-04-01

    Recent theoretical research on spatiobiologically integrated radiotherapy has focused on optimization models that adapt fluence-maps to the evolution of tumor state, for example, cell densities, as observed in quantitative functional images acquired over the treatment course. We propose an optimization model that adapts the length of the treatment course as well as the fluence-maps to such imaged tumor state. Specifically, after observing the tumor cell densities at the beginning of a session, the treatment planner solves a group of convex optimization problems to determine an optimal number of remaining treatment sessions, and a corresponding optimal fluence-map for each of these sessions. The objective is to minimize the total number of tumor cells remaining (TNTCR) at the end of this proposed treatment course, subject to upper limits on the biologically effective dose delivered to the organs-at-risk. This fluence-map is administered in future sessions until the next image is available, and then the number of sessions and the fluence-map are re-optimized based on the latest cell density information. We demonstrate via computer simulations on five head-and-neck test cases that such adaptive treatment-length and fluence-map planning reduces the TNTCR and increases the biological effect on the tumor while employing shorter treatment courses, as compared to only adapting fluence-maps and using a pre-determined treatment course length based on one-size-fits-all guidelines.

  3. Step styles of pedestrians at different densities

    Science.gov (United States)

    Wang, Jiayue; Weng, Wenguo; Boltes, Maik; Zhang, Jun; Tordeux, Antoine; Ziemer, Verena

    2018-02-01

    Stepping locomotion is the basis of human movement. The investigation of stepping locomotion and its affecting factors is necessary for a more realistic knowledge of human movement, which is usually referred to as walking with equal step lengths for the right and left leg. To study pedestrians’ stepping locomotion, a set of single-file movement experiments involving 39 participants of the same age walking on a highly curved oval course is conducted. The microscopic characteristics of the pedestrians including 1D Voronoi density, speed, and step length are calculated based on a projected coordinate. The influence of the projection lines with different radii on the measurement of these quantities is investigated. The step lengths from the straight and curved parts are compared using the Kolmogorov–Smirnov test. During the experiments, six different step styles are observed and the proportions of different step styles change with the density. At low density, the main step style is the stable-large step style and the step lengths of one pedestrian are almost constant. At high density, some pedestrians adjust and decrease their step lengths. Some pedestrians take relatively smaller and larger steps alternately to adapt to limited space.

  4. Effect of plantation density on kraft pulp production from red pine (Pinus resinosa Ait.)

    Science.gov (United States)

    J.Y. Zhu; G.C. Myers

    2006-01-01

    Red pine (Pinus resinosa Ait.) butt logs from 38 year old research plots were used to study the effect of plantation stand density on kraft pulp production. Results indicate that plantation stand density can affect pulp yield, unrefined pulp mean fibre length, and the response of pulp fibre length to pulp refining. However, the effect of plantation stand density on...

  5. Work-Related Lung Disease Surveillance System (eWoRLD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — A surveillance system that provides morbidity, mortality, and workplace exposure data on work-related respiratory diseases by geographic region, industry and...

  6. 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...

  7. Bond lengths in organic and metal-organic compounds revisited: X-H bond lengths from neutron diffraction data.

    Science.gov (United States)

    Allen, Frank H; Bruno, Ian J

    2010-06-01

    The number of structures in the Cambridge Structural Database (CSD) has increased by an order of magnitude since the preparation of two major compilations of standard bond lengths in mid-1985. It is now of interest to examine whether this huge increase in data availability has implications for the mean bond-length values published in the late 1980s. Those compilations reported mean X-H bond lengths derived from rather sparse information and for rather few chemical environments. During the intervening years, the number of neutron studies has also increased, although only by a factor of around 2.25, permitting a new analysis of X-H bond-length distributions for (a) organic X = C, N, O, B, and (b) a variety of terminal and homometallic bridging transition metal hydrides. New mean values are reported here and are compared with earlier results. These new overall means are also complemented by an analysis of X-H distances at lower temperatures (T chemical environments for which statistically acceptable mean X-H bond lengths can be obtained, although values from individual structures are also collated to further extend the chemical range of this compilation. Updated default 'neutron-normalization' distances for use in hydrogen-bond and deformation-density studies are also proposed for C-H, N-H and O-H, and the low-temperature analysis provides specific values for certain chemical environments and hybridization states of X.

  8. Complete Fabrication of a Traversable 3 µm Thick NbN Film Superconducting Coil with Cu plated layer of 42m in Length in a Spiral Three-Storied Trench Engraved in a Si Wafer of 76.2 mm in Diameter Formed by MEMS Technology for a Compact SMES with High Energy Storage Volume Density

    Science.gov (United States)

    Suzuki, Yasuhiro; Iguchi, Nobuhiro; Adachi, Kazuhiro; Ichiki, Akihisa; Hioki, Tatsumi; Hsu, Che-Wei; Sato, Ryoto; Kumagai, Shinya; Sasaki, Minoru; Noh, Joo-Hyong; Sakurahara, Yuuske; Okabe, Kyohei; Takai, Osamu; Honma, Hideo; Watanabe, Hideo; Sakoda, Hitoshi; Sasagawa, Hiroaki; Doy, Hideyuki; Zhou, Shuliang; Hori, H.; Nishikawa, Shigeaki; Nozaki, Toshihiro; Sugimoto, Noriaki; Motohiro, Tomoyoshi

    2017-09-01

    Based on the concept of a novel approach to make a compact SMES unit composed of a stack of Si wafers using MEMS process proposed previously, a complete fabrication of a traversable 3 µam thick NbN film superconducting coil lined with Cu plated layer of 42m in length in a spiral three-storied trench engraved in and extended over a whole Si-wafer of 76.2 mm in diameter was attained for the first time. With decrease in temperature, the DC resistivity showed a metallic decrease indicating the current pass was in the Cu plated layer and then made a sudden fall to residual contact resistance indicating the shift of current pass from the Cu plated layer to the NbN film at the critical temperature Tc of 15.5K by superconducting transition. The temperature dependence of I-V curve showed the increase in the critical current with decrease in the temperature and the highest critical current measured was 220 mA at 4K which is five times as large as that obtained in the test fabrication as the experimental proof of concept presented in the previous report. This completion of a one wafer superconducting NbN coil is an indispensable step for the next proof of concept of fabrication of series-connected two wafer coils via superconductive joint which will read to series connected 600 wafer coils finally, and for replacement of NbN by high Tc superconductor such as YBa2Cu3O7-x for operation under the cold energy of liquid hydrogen or liquid nitrogen.

  9. Electrostatic stiffening and induced persistence length for coassembled molecular bottlebrushes

    Science.gov (United States)

    Storm, Ingeborg M.; Stuart, Martien A. Cohen; de Vries, Renko; Leermakers, Frans A. M.

    2018-03-01

    A self-consistent field analysis for tunable contributions to the persistence length of isolated semiflexible polymer chains including electrostatically driven coassembled deoxyribonucleic acid (DNA) bottlebrushes is presented. When a chain is charged, i.e., for polyelectrolytes, there is, in addition to an intrinsic rigidity, an electrostatic stiffening effect, because the electric double layer resists bending. For molecular bottlebrushes, there is an induced contribution due to the grafts. We explore cases beyond the classical phantom main-chain approximation and elaborate molecularly more realistic models where the backbone has a finite volume, which is necessary for treating coassembled bottlebrushes. We find that the way in which the linear charge density or the grafting density is regulated is important. Typically, the stiffening effect is reduced when there is freedom for these quantities to adapt to the curvature stresses. Electrostatically driven coassembled bottlebrushes, however, are relatively stiff because the chains have a low tendency to escape from the compressed regions and the electrostatic binding force is largest in the convex part. For coassembled bottlebrushes, the induced persistence length is a nonmonotonic function of the polymer concentration: For low polymer concentrations, the stiffening grows quadratically with coverage; for semidilute polymer concentrations, the brush chains retract and regain their Gaussian size. When doing so, they lose their induced persistence length contribution. Our results correlate well with observed physical characteristics of electrostatically driven coassembled DNA-bioengineered protein-polymer bottlebrushes.

  10. Application of a single root-scale model to improve macroscopic modeling of root water uptake: focus on osmotic stress

    Science.gov (United States)

    Jorda, Helena; Perelman, Adi; Lazarovitch, Naftali; Vanderborght, Jan

    2017-04-01

    Root water uptake is a fundamental process in the hydrological cycle and it largely regulates the water balance in the soil vadose zone. Macroscopic stress functions are currently used to estimate the effect of salinity on root water uptake. These functions commonly assume stress to be a function of bulk salinity and of the plant sensitivity to osmotic stress expressed as the salinity at which transpiration is reduced by half or so called tolerance value. However, they fail to integrate additional relevant factors such as atmospheric conditions or root architectural traits. We conducted a comprehensive simulation study on a single root using a 3-D physically-based model that resolves flow and transport to individual root segments and that couples flow in the soil and root system. The effect of salt concentrations on root water uptake was accounted for by including osmotic water potential gradients between the solution at the soil root interface and the root xylem sap in the hydraulic gradient between the soil and root. A large set of factors were studied, namely, potential transpiration rate and dynamics, root length density (RLD), irrigation water quality and irrigation frequency, and leaching fraction. Results were fitted to the macroscopic function developed by van Genuchten and Hoffman (1984) and the dependency of osmotic stress and the fitted macroscopic parameters on the studied factors was evaluated. Osmotic stress was found to be highly dependent on RLD. Low RLDs result in a larger stress to the plant due to high evaporative demand per root length unit. In addition, osmotic stress was positively correlated to potential transpiration rate, and sinusoidal potential transpiration lead to larger stress than when imposed as a constant boundary condition. Macroscopic parameters are usually computed as single values for each crop and used for the entire growing season. However, our study shows that both tolerance value and shape parameter p from the van Genuchten

  11. Densities and Excess Molar Volume for the Ternary Systems (1 ...

    African Journals Online (AJOL)

    methylimidazolium methyl sulphate ([BMIM]+[MeSO4]-) were determined. The ternary systems studied were ... The results are interpreted in terms of the alcohol chain length and the intermolecular interactions. KEYWORDS Density, excess molar ...

  12. Density of oxidation-induced stacking faults in damaged silicon

    NARCIS (Netherlands)

    Kuper, F.G.; Hosson, J.Th.M. De; Verwey, J.F.

    1986-01-01

    A model for the relation between density and length of oxidation-induced stacking faults on damaged silicon surfaces is proposed, based on interactions of stacking faults with dislocations and neighboring stacking faults. The model agrees with experiments.

  13. [Population density of Eucalyptus urophylla plantation].

    Science.gov (United States)

    Huang, B; Lu, C

    2000-02-01

    This paper dealt with the relationships and correlation models of the population density of 5.6 years old Eucalyptus urophylla plantation with its crown width, diamter at breast height(DBH), tree height, individual standing volume, stand volume, wood properties and survital rate. The results showed that the population density remarkably affected DBH, individual standing volume, crown width, live branch height, stand volume and wood fiber width; but not affect tree height, basic density of wood, and length of wood fibers. It had a positive relationship with stand volume, live branch height and wood fibers width, and a negative relationship with DBH, individual standing volume and crown width. In addition, E. urophylla had a wide range of reasonable density. For short-rotation puplwoods, the optimum planting density of E. urophylla is 2000 individuals per hectare.

  14. Short Rayleigh Length Free Electron Lasers

    CERN Document Server

    Crooker, P P; Armstead, R L; Blau, J

    2004-01-01

    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 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. A new FEL interaction is described and analyzed with a Rayleigh length that is only one tenth the undulator length, or less. The effect of mirror vibration and positioning are more critical in the short Rayleigh length design, but we find that they are still within normal design tolerances.

  15. Radiographic assessment of endodontic working length

    OpenAIRE

    Osama S Alothmani; Lara T Friedlander; Nicholas P Chandler

    2013-01-01

    The use of radiographs for working length determination is usual practice in endodontics. Exposing radiographs following the principles of the paralleling technique allows more accurate length determination compared to the bisecting-angle method. However, it has been reported that up to 28.5% of cases can have the file tip extending beyond the confines of the root canals despite an acceptable radiographic appearance. The accuracy of radiographic working length determination could be affected ...

  16. Laboratory Density Functionals

    OpenAIRE

    Giraud, B. G.

    2007-01-01

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  17. Information, polarization and term length in democracy

    DEFF Research Database (Denmark)

    Schultz, Christian

    2008-01-01

    accountable, but the re-election incentive leads to policy-distortion as the government seeks to manipulate swing voters' beliefs to make its ideology more popular. This creates a trade-off: A short term length improves accountability but gives distortions. A short term length is best for swing voters when......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...

  18. Convective equilibrium and mixing-length theory for stellarator reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    In high ..beta.. stellarator and tokamak reactors, the plasma pressure gradient in some regions of the plasma may exceed the critical pressure gradient set by ballooning instabilities. In these regions, convective cells break out to enhance the transport. As a result, the pressure gradient can rise only slightly above the critical gradient and the plasma is in another state of equilibrium - ''convective equilibrium'' - in these regions. Although the convective transport cannot be calculated precisely, it is shown that the density and temperature profiles in the convective region can still be estimated. A simple mixing-length theory, similar to that used for convection in stellar interiors, is introduced in this paper to provide a qualitative description of the convective cells and to show that the convective transport is highly efficient. A numerical example for obtaining the density and temperature profiles in a stellarator reactor is given.

  19. Convective equilibrium and mixing-length theory for stellarator reactors

    International Nuclear Information System (INIS)

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    In high β stellarator and tokamak reactors, the plasma pressure gradient in some regions of the plasma may exceed the critical pressure gradient set by ballooning instabilities. In these regions, convective cells break out to enhance the transport. As a result, the pressure gradient can rise only slightly above the critical gradient and the plasma is in another state of equilibrium - ''convective equilibrium'' - in these regions. Although the convective transport cannot be calculated precisely, it is shown that the density and temperature profiles in the convective region can still be estimated. A simple mixing-length theory, similar to that used for convection in stellar interiors, is introduced in this paper to provide a qualitative description of the convective cells and to show that the convective transport is highly efficient. A numerical example for obtaining the density and temperature profiles in a stellarator reactor is given

  20. Analysis and Optimization of "Full-Length" Diodes

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    2012-01-19

    A method of analyzing the axial variation of the heat generation rate, temperature, voltage, current density and emitter heat flux in a thermionic converter is described. The method is particularly useful for the case of "long" diodes, each extending over the full length of the reactor core. For a given diode geometry and fuel distribution, the analysis combines a nuclear solution of the axial fission density profile with the iterative solution of four differential equations representing the thermal, electrical, and thermionic interactions within the diode. The digital computer program developed to solve these equations can also perform a design optimization with respect to lead resistance, load voltage, and emitter thickness, for a specified maximum emitter temperature. Typical results are presented, and the use of this analysis for predicting the diode operating characteristics is illustrated.

  1. Density and surface tension of ionic liquids.

    Science.gov (United States)

    Kolbeck, C; Lehmann, J; Lovelock, K R J; Cremer, T; Paape, N; Wasserscheid, P; Fröba, A P; Maier, F; Steinrück, H-P

    2010-12-30

    We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf(2)N](-))-based and 12 1-methyl-3-octylimidazolium ([C(8)C(1)Im](+))-based ionic liquids (ILs) with the vibrating tube and the pendant drop method, respectively. This comprehensive set of ILs was chosen to probe the influence of the cations and anions on density and surface tension. When the alkyl chain length in the [C(n)C(1)Im][Tf(2)N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease in density is observed. The surface tension initially also decreases but reaches a plateau for alkyl chain lengths greater than n = 8. Functionalizing the alkyl chains with ethylene glycol groups results in a higher density as well as a higher surface tension. For the dependence of density and surface tension on the chemical nature of the anion, relations are only found for subgroups of the studied ILs. Density and surface tension values are discussed with respect to intermolecular interactions and surface composition as determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). The absence of nonvolatile surface-active contaminants was proven by ARXPS.

  2. 7 CFR 29.3037 - Length.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Length. 29.3037 Section 29.3037 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... Length, as an element of quality, does not apply to tobacco in strip form. (See Elements of quality.) [24...

  3. 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 the...

  4. Local gauge invariant QED with fundamental length

    International Nuclear Information System (INIS)

    Kadyshevsky, V.G.; Mateev, M.D.

    1981-01-01

    A local gauge theory of electromagnetic interactions with the fundamental length l as a new universal scale is worked out. The Lagrangian contains new extra terms in which the coupling constant is proportional to the fundamental length. The theory has an elegant geometrical basis: in momentum representation one faces de Sitter momentum space with curvature radius 1/l [ru

  5. 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.

  6. The length of the male urethra

    Directory of Open Access Journals (Sweden)

    Tobias. S. Kohler

    2008-08-01

    Full Text Available PURPOSE: Catheter-based medical devices are an important component of the urologic armamentarium. To our knowledge, there is no population-based data regarding normal male urethral length. We evaluated the length of the urethra in men with normal genitourinary anatomy undergoing either Foley catheter removal or standard cystoscopy. MATERIALS AND METHODS: Male urethral length was obtained in 109 men. After study permission was obtained, the subject's penis was placed on a gentle stretch and the catheter was marked at the tip of the penis. The catheter was then removed and the distance from the mark to the beginning of the re-inflated balloon was measured. Alternatively, urethral length was measured at the time of cystoscopy, on removal of the cystoscope. Data on age, weight, and height was obtained in patients when possible. RESULTS: The mean urethral length was 22.3 cm with a standard deviation of 2.4 cm. Urethral length varied between 15 cm and 29 cm. No statistically significant correlation was found between urethral length and height, weight, body mass index (BMI, or age. CONCLUSIONS: Literature documenting the length of the normal male adult urethra is scarce. Our data adds to basic anatomic information of the male urethra and may be used to optimize genitourinary device design.

  7. On the homology length spectrum of surfaces

    OpenAIRE

    Massart, Daniel; Parlier, Hugo

    2014-01-01

    On a surface with a Finsler metric, we investigate the asymptotic growth of the number of closed geodesics of length less than L which minimize length among all geodesic multicurves in the same homology class. An important class of surfaces which are of interest to us are hyperbolic surfaces.

  8. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

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

    2015-01-01

    Telomere length, a highly heritable trait, is longer in offspring of older fathers. This perplexing feature has been attributed to the longer telomeres in sperm of older men and it might be an 'epigenetic' mechanism through which paternal age plays a role in telomere length regulation in humans...

  9. Influence of mandibular length on mouth opening

    NARCIS (Netherlands)

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

    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

  10. Progress in Long Scale Length Laser-Plasma Interactions

    International Nuclear Information System (INIS)

    Glenzer, S H; Arnold, P; Bardsley, G; Berger, R L; Bonanno, G; Borger, T; Bower, D E; Bowers, M; Bryant, R; Buckman, S.; Burkhart, S C; Campbell, K; Chrisp, M P; Cohen, B I; Constantin, G; Cooper, F; Cox, J; Dewald, E; Divol, L; Dixit, S; Duncan, J; Eder, D; Edwards, J; Erbert, G; Felker, B; Fornes, J; Frieders, G; Froula, D H; Gardner, S D; Gates, C; Gonzalez, M; Grace, S; Gregori, G; Greenwood, A; Griffith, R; Hall, T; Hammel, B A; Haynam, C; Heestand, G; Henesian, M; Hermes, G; Hinkel, D; Holder, J; Holdner, F; Holtmeier, G; Hsing, W; Huber, S; James, T; Johnson, S; Jones, O S; Kalantar, D; Kamperschroer, J H; Kauffman, R; Kelleher, T; Knight, J; Kirkwood, R K; Kruer, W L; Labiak, W; Landen, O L; Langdon, A B; Langer, S; Latray, D; Lee, A; Lee, F D; Lund, D; MacGowan, B; Marshall, S; McBride, J; McCarville, T; McGrew, L; Mackinnon, A J; Mahavandi, S; Manes, K; Marshall, C; Mertens, E; Meezan, N; Miller, G; Montelongo, S; Moody, J D; Moses, E; Munro, D; Murray, J; Neumann, J; Newton, M; Ng, E; Niemann, C; Nikitin, A; Opsahl, P; Padilla, E; Parham, T; Parrish, G; Petty, C; Polk, M; Powell, C; Reinbachs, I; Rekow, V; Rinnert, R; Riordan, B; Rhodes, M.

    2003-01-01

    The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 mm and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3ω) with a total intensity of 2 x 10 15 W cm -2 . The targets were filled with 1 atm of CO 2 producing of up to 7 mm long homogeneously heated plasmas with densities of n e = 6 x 10 20 cm -3 and temperatures of T e = 2 keV. The high energy in a NIF quad of beams of 16kJ, illuminating the target from one direction, creates unique conditions for the study of laser plasma interactions at scale lengths not previously accessible. The propagation through the large-scale plasma was measured with a gated x-ray imager that was filtered for 3.5 keV x rays. These data indicate that the beams interact with the full length of this ignition-scale plasma during the last ∼1 ns of the experiment. During that time, the full aperture measurements of the stimulated Brillouin scattering and stimulated Raman scattering show scattering into the four focusing lenses of 6% for the smallest length (∼2 mm). increasing to 12% for ∼7 mm. These results demonstrate the NIF experimental capabilities and further provide a benchmark for three-dimensional modeling of the laser-plasma interactions at ignition-size scale lengths

  11. Progress in long scale length laser plasma interactions

    Science.gov (United States)

    Glenzer, S. H.; Arnold, P.; Bardsley, G.; Berger, R. L.; Bonanno, G.; Borger, T.; Bower, D. E.; Bowers, M.; Bryant, R.; Buckman, S.; Burkhart, S. C.; Campbell, K.; Chrisp, M. P.; Cohen, B. I.; Constantin, C.; Cooper, F.; Cox, J.; Dewald, E.; Divol, L.; Dixit, S.; Duncan, J.; Eder, D.; Edwards, J.; Erbert, G.; Felker, B.; Fornes, J.; Frieders, G.; Froula, D. H.; Gardner, S. D.; Gates, C.; Gonzalez, M.; Grace, S.; Gregori, G.; Greenwood, A.; Griffith, R.; Hall, T.; Hammel, B. A.; Haynam, C.; Heestand, G.; Henesian, M.; Hermes, G.; Hinkel, D.; Holder, J.; Holdner, F.; Holtmeier, G.; Hsing, W.; Huber, S.; James, T.; Johnson, S.; Jones, O. S.; Kalantar, D.; Kamperschroer, J. H.; Kauffman, R.; Kelleher, T.; Knight, J.; Kirkwood, R. K.; Kruer, W. L.; Labiak, W.; Landen, O. L.; Langdon, A. B.; Langer, S.; Latray, D.; Lee, A.; Lee, F. D.; Lund, D.; MacGowan, B.; Marshall, S.; McBride, J.; McCarville, T.; McGrew, L.; Mackinnon, A. J.; Mahavandi, S.; Manes, K.; Marshall, C.; Menapace, J.; Mertens, E.; Meezan, N.; Miller, G.; Montelongo, S.; Moody, J. D.; Moses, E.; Munro, D.; Murray, J.; Neumann, J.; Newton, M.; Ng, E.; Niemann, C.; Nikitin, A.; Opsahl, P.; Padilla, E.; Parham, T.; Parrish, G.; Petty, C.; Polk, M.; Powell, C.; Reinbachs, I.; Rekow, V.; Rinnert, R.; Riordan, B.; Rhodes, M.; Roberts, V.; Robey, H.; Ross, G.; Sailors, S.; Saunders, R.; Schmitt, M.; Schneider, M. B.; Shiromizu, S.; Spaeth, M.; Stephens, A.; Still, B.; Suter, L. J.; Tietbohl, G.; Tobin, M.; Tuck, J.; Van Wonterghem, B. M.; Vidal, R.; Voloshin, D.; Wallace, R.; Wegner, P.; Whitman, P.; Williams, E. A.; Williams, K.; Winward, K.; Work, K.; Young, B.; Young, P. E.; Zapata, P.; Bahr, R. E.; Seka, W.; Fernandez, J.; Montgomery, D.; Rose, H.

    2004-12-01

    The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3ω) with a total intensity of 2 × 1015 W cm-2. The targets were filled with 1 atm of CO2 producing up to 7 mm long homogeneously heated plasmas with densities of ne = 6 × 1020 cm-3 and temperatures of Te = 2 keV. The high energy in an NIF quad of beams of 16 kJ, illuminating the target from one direction, creates unique conditions for the study of laser-plasma interactions at scale lengths not previously accessible. The propagation through the large-scale plasma was measured with a gated x-ray imager that was filtered for 3.5 keV x-rays. These data indicate that the beams interact with the full length of this ignition-scale plasma during the last ~1 ns of the experiment. During that time, the full aperture measurements of the stimulated Brillouin scattering and stimulated Raman scattering show scattering into the four focusing lenses of 3% for the smallest length (~2 mm), increasing to 10-12% for ~7 mm. These results demonstrate the NIF experimental capabilities and further provide a benchmark for three-dimensional modelling of the laser-plasma interactions at ignition-size scale lengths.

  12. Radiographic assessment of endodontic working length

    Directory of Open Access Journals (Sweden)

    Osama S Alothmani

    2013-01-01

    Full Text Available The use of radiographs for working length determination is usual practice in endodontics. Exposing radiographs following the principles of the paralleling technique allows more accurate length determination compared to the bisecting-angle method. However, it has been reported that up to 28.5% of cases can have the file tip extending beyond the confines of the root canals despite an acceptable radiographic appearance. The accuracy of radiographic working length determination could be affected by the location of the apical foramen, tooth type, canal curvature and superimposition of surrounding structures. Variations among observers by virtue of training and experience may also influence the accuracy of the procedure. The interpretation of radiographs could be affected by film speed and viewing conditions, with the superiority of digital imaging over conventional radiography for working length determination remaining debatable. The combination of several methods is recommended for acquiring the most accurate working length.

  13. Economic issues of broiler production length

    Directory of Open Access Journals (Sweden)

    Szőllősi László

    2014-01-01

    Full Text Available The length of broiler production cycle is also an important factor when profitability is measured. This paper is to determine the effects of different market ages and down-time period, overall broiler production cycle length on performance and economic parameters based on Hungarian production and financial circumstances. A deterministic model was constructed to manage the function-like correlations of age-related daily weight gain, daily feed intake and daily mortality data. The results show that broiler production cycle length has a significant effect on production and economic performance. Cycle length is determined by the length of down-time and grow-out periods. If down-time period is reduced by one day, an average net income of EUR 0.55 per m2 is realizable. However, the production period is not directly proportional either with emerging costs or obtainable revenues. Profit maximization is attainable if the production period is 41-42 days.

  14. Screening length in dusty plasma crystals

    International Nuclear Information System (INIS)

    Nikolaev, V S; Timofeev, A V

    2016-01-01

    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. (paper)

  15. Geostatistical analysis of GPS trajectory data: Space-time densities

    NARCIS (Netherlands)

    Hengl, T.; van Loon, E.E.; Shamoun-Baranes, J.; Bouten, W.; Zhang, J.; Goodchild, M.F.

    2008-01-01

    Creation of density maps and estimation of home range is problematic for observations of animal movement at irregular intervals. We propose a technique to estimate space-time densities by separately modeling animal movement paths and velocities, both as continuous fields. First the length of

  16. Kidney Length in Normal Korean Children

    International Nuclear Information System (INIS)

    Kim, In One; Cheon, Jung Eun; Lee, Young Seok; Lee, Sun Wha; Kim, Ok Hwa; Kim, Ji Hye; Kim, Hong Dae; Sim, Jung Suk

    2010-01-01

    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

  17. [Seasonal dynamics of quantitative and morphological traits of poplar fine roots and their differences between successive rotation plantations].

    Science.gov (United States)

    Wang, Yan-ping; Xu, Tan; Zhu, Wan-rui; Wang, Qi-tong; Liu, Meng-ling; Wang, Hua-tian; Li, Chuan-rong; Dong, Yu-feng

    2016-02-01

    Based on the fine root samples of the first and second generations of poplar (Populus x euramericana ' Neva'), this study examined the response of quantitative and morphological traits of fine roots of different orders and the difference between generations. The results showed that, the quantitative traits of fine roots, such as root length, root surface area and root biomass, presented obvious seasonal variation, and the fine root traits had obvious difference among root orders. The quantitative traits of lower-order fine roots showed significant seasonal difference, and the fine root biomass increased in the growing season and then decreased significantly. The specific root length (SRL) of higher-order roots also showed significant change with season, while the root length density (RLD) and root tissue density (RTD) changed a little. The successive rotation resulted in the significant increase of root length, root biomass, SRL and RLD of 1-2 orders in the growing season. The quantitative traits of first order root significantly positively correlated with soil temperature and moisture, and significantly negatively correlated with the soil organic matter and soil available nitrogen content. However, the quantitative traits of second order root only showed significant correlation with soil nutrient content. The seasonal dynamics of poplar fine roots and the difference between successive rotation plantations implied carbon investment change of poplar to roots. Soil nutrient deficiency induced more carbon investment into roots, and this carbon allocation pattern might affect the aboveground productivity of poplar plantation.

  18. Measurement of the diffusion length of thermal neutrons in the beryllium oxide

    International Nuclear Information System (INIS)

    Koechlin, J.C.; Martelly, J.; Duggal, V.P.

    1955-01-01

    The diffusion length of thermal neutrons in the beryllium oxide has been obtained while studying the spatial distribution of the neutrons in a massive parallelepiped of this matter placed before the thermal column of the reactor core of Saclay. The mean density of the beryllium oxide (BeO) is 2,95 gr/cm 3 , the mean density of the massif is 2,92 gr/cm 3 . The value of the diffusion length, deducted of the done measures, is: L = 32,7 ± 0,5 cm (likely gap). Some remarks are formulated about the influence of the spectral distribution of the neutrons flux used. (authors) [fr

  19. Zero-point length from string fluctuations

    International Nuclear Information System (INIS)

    Fontanini, Michele; Spallucci, Euro; Padmanabhan, T.

    2006-01-01

    One of the leading candidates for quantum gravity, viz. string theory, has the following features incorporated in it. (i) The full spacetime is higher-dimensional, with (possibly) compact extra-dimensions; (ii) there is a natural minimal length below which the concept of continuum spacetime needs to be modified by some deeper concept. On the other hand, the existence of a minimal length (zero-point length) in four-dimensional spacetime, with obvious implications as UV regulator, has been often conjectured as a natural aftermath of any correct quantum theory of gravity. We show that one can incorporate the apparently unrelated pieces of information-zero-point length, extra-dimensions, string T-duality-in a consistent framework. This is done in terms of a modified Kaluza-Klein theory that interpolates between (high-energy) string theory and (low-energy) quantum field theory. In this model, the zero-point length in four dimensions is a 'virtual memory' of the length scale of compact extra-dimensions. Such a scale turns out to be determined by T-duality inherited from the underlying fundamental string theory. From a low energy perspective short distance infinities are cutoff by a minimal length which is proportional to the square root of the string slope, i.e., α ' . Thus, we bridge the gap between the string theory domain and the low energy arena of point-particle quantum field theory

  20. Future Road Density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  1. Detecting many-body-localization lengths with cold atoms

    Science.gov (United States)

    Guo, Xuefei; Li, Xiaopeng

    2018-03-01

    Considering ultracold atoms in optical lattices, we propose experimental protocols to study many-body-localization (MBL) length and criticality in quench dynamics. Through numerical simulations with exact diagonalization, we show that in the MBL phase the perturbed density profile following a local quench remains exponentially localized in postquench dynamics. The size of this density profile after long-time-dynamics defines a localization length, which tends to diverge at the MBL-to-ergodic transition as we increase the system size. The determined localization transition point agrees with previous exact diagonalization calculations using other diagnostics. Our numerical results provide evidence for violation of the Harris-Chayes bound for the MBL criticality. The critical exponent ν can be extracted from our proposed dynamical procedure, which can then be used directly in experiments to determine whether the Harris-Chayes-bound holds for the MBL transition. These proposed protocols to detect localization criticality are justified by benchmarking to the well-established results for the noninteracting three-dimensional Anderson localization.

  2. Density distributions and depth in flocks

    Science.gov (United States)

    Lewis, J. M.; Turner, M. S.

    2017-12-01

    Recent experimental evidence suggests that interactions in flocks of birds do not involve a characteristic length scale. Bird flocks have also been revealed to have an inhomogeneous density distribution, with the density of birds near the border greater than near the centre. We introduce a strictly metric-free model for collective behaviour that incorporates a distributed motional bias, providing control of the density distribution. A simple version of this model is then able to provide a good fit to published data for the density variation across flocks of Starlings. We find that it is necessary for individuals on the edge of the flock to have an inward motional bias but that birds in the interior of the flock instead must have an outward bias. We discuss the ability of individuals to determine their depth within a flock and show how this might be achieved by relatively simple analysis of their visual environment.

  3. Density controlled carbon nanotube array electrodes

    Science.gov (United States)

    Ren, Zhifeng F [Newton, MA; Tu, Yi [Belmont, MA

    2008-12-16

    CNT materials comprising aligned carbon nanotubes (CNTs) with pre-determined site densities, catalyst substrate materials for obtaining them and methods for forming aligned CNTs with controllable densities on such catalyst substrate materials are described. The fabrication of films comprising site-density controlled vertically aligned CNT arrays of the invention with variable field emission characteristics, whereby the field emission properties of the films are controlled by independently varying the length of CNTs in the aligned array within the film or by independently varying inter-tubule spacing of the CNTs within the array (site density) are disclosed. The fabrication of microelectrode arrays (MEAs) formed utilizing the carbon nanotube material of the invention is also described.

  4. 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.

  5. Dosimetric Properties of Plasma Density Effects on Laser-Accelerated VHEE Beams Using a Sharp Density-Transition Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seung Hoon; Cho, Sungho; Kim, Eun Ho; Park, Jeong Hoon; Jung, Won-Gyun; Kim, Geun Beom; Kim, Kum Bae [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Min, Byung Jun [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jaehoon [Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Jeong, Hojin [Gyeongsang National University Hospital, Jinju (Korea, Republic of); Lee, Kitae [Korea Atomic Energy Research Institute, Deajeon (Korea, Republic of); Park, Sung Yong [Karmanos Cancer Institute, Michigan (United States)

    2017-01-15

    In this paper, the effects of the plasma density on laser-accelerated electron beams for radiation therapy with a sharp density transition are investigated. In the sharp density-transition scheme for electron injection, the crucial issue is finding the optimum density conditions under which electrons injected only during the first period of the laser wake wave are accelerated further. In this paper, we report particle-in-cell simulation results for the effects of both the scale length and the density transition ratio on the generation of a quasi-mono-energetic electron bunch. The effects of both the transverse parabolic channel and the plasma length on the electron-beam's quality are investigated. Also, we show the experimental results for the feasibility of a sharp density-transition structure. The dosimetric properties of these very high-energy electron beams are calculated using Monte Carlo simulations.

  6. Crowding and Density

    Science.gov (United States)

    Design and Environment, 1972

    1972-01-01

    Three-part report pinpointing problems and uncovering solutions for the dual concepts of density (ratio of people to space) and crowding (psychological response to density). Section one, A Primer on Crowding,'' reviews new psychological and social findings; section two, Density in the Suburbs,'' shows conflict between status quo and increased…

  7. Density Functional Theory

    Indian Academy of Sciences (India)

    (1) The total energy of an electron system in an external potential is a unique functional of the total electron density; and. (2)The density that minimizes the energy is the ground-state density, and this minimum energy is the ground-state energy of the system.

  8. Scattered light evidence for short density scale heights near critical density in laser-irradiated plasmas

    International Nuclear Information System (INIS)

    Phillion, D.W.; Lerche, R.A.; Rupert, V.C.; Haas, R.A.; Boyle, M.J.

    1976-01-01

    Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 μ light. Both 10 μ thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, we infer scale lengths on the order of one micron. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length

  9. Scattered light evidence for short density scale heights near critical density in laser-irradiated plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Phillion, D.W.; Lerche, R.A.; Rupert, V.C.; Haas, R.A.; Boyle, M.J.

    1976-09-15

    Experimental evidence is presented of a steepened electron density profile near critical density obtained from studying the time-integrated scattered light from targets illuminated by linearly polarized, 1.06 ..mu.. light. Both 10 ..mu.. thick disks and DT-filled glass microshells were irradiated by light focused by f/1 or f/2.5 lenses in one and two-beam experiments, respectively. From the dependence of the asymmetry of the scattered light about the beam axis upon the scattering angle, we infer scale lengths on the order of one micron. Scale lengths have also been deduced from measurements on the polarization state of the reflected light. Both analytic and numerical results are presented to show how the polarization state varies with the incidence angle and the scale length.

  10. Transition in multiple-scale-lengths turbulence in plasmas

    International Nuclear Information System (INIS)

    Itoh, S.-I.; Yagi, M.; Kawasaki, M.; Kitazawa, A.

    2002-02-01

    The statistical theory of strong turbulence in inhomogeneous plasmas is developed for the cases where fluctuations with different scale-lengths coexist. Statistical nonlinear interactions between semi-micro and micro modes are first kept in the analysis as the drag, noise and drive. The nonlinear dynamics determines both the fluctuation levels and the cross field turbulent transport for the fixed global parameters. A quenching or suppressing effect is induced by their nonlinear interplay, even if both modes are unstable when analyzed independently. Influence of the inhomogeneous global radial electric field is discussed. A new insight is given for the physics of internal transport barrier. The thermal fluctuation of the scale length of λ D is assumed to be statistically independent. The hierarchical structure is constructed according to the scale lengths. Transitions in turbulence are found and phase diagrams with cusp type catastrophe are obtained. Dynamics is followed. Statistical properties of the subcritical excitation are discussed. The probability density function (PDF) and transition probability are obtained. Power-laws are obtained in the PDF as well as in the transition probability. Generalization for the case where turbulence is composed of three-classes of modes is also developed. A new catastrophe of turbulent sates is obtained. (author)

  11. Vacuum heating evaluation for plasmas of exponentially decreasing density profile

    International Nuclear Information System (INIS)

    Pestehe, S.J.; Mohammadnejad, M.

    2008-01-01

    Ultra-short pulse lasers have opened a regime of laser-plasma interaction where plasmas have scale lengths shorter than the laser wavelength and allow the possibility of generating near-solid density plasmas. The interaction of high-intensity laser beams with sharply bounded high-density and small scale length plasmas is considered. Absorption of the laser energy associated with the mechanism of dragging electrons out of the plasma into the vacuum and sending them back into the plasma with the electric field component along the density gradient, so called vacuum heating, is studied. An exponentially decreasing electron density profile is assumed. The vector potential of the electromagnetic field propagating through the plasma is calculated and the behaviour of the electric and magnetic components of the electromagnetic field is studied. The fraction of laser power absorbed in this process is calculated and plotted versus the laser beam incidence angle, illumination energy, and the plasma scale length

  12. Combined effects of thinning and decline on fine root dynamics in a Quercus robur L. forest adjoining the Italian Pre-Alps.

    Science.gov (United States)

    Mosca, E; Montecchio, L; Barion, G; Dal Cortivo, C; Vamerali, T

    2017-05-01

    Oak decline is a complex phenomenon, characterized by symptoms of canopy transparency, bark cracks and root biomass reduction. Root health status is one of the first stress indicators, and root turnover is a key process in plant adaptation to unfavourable conditions. In this study, the combined effects of decline and thinning were evaluated on fine root dynamics in an oak forest adjoining the Italian Pre-Alps by comparison of acute declining trees with non-declining trees, both with and without thinning treatment of surrounding trees. Dynamics of volumetric root length density (RLD V ) and tip density (RTD V ), root tip density per unit length of root (RTD L ), diameter, branching index (BI) and mycorrhizal colonization were monitored by soil coring over 2 years as possible descriptors of decline. At the beginning of the experiment, the relationship between canopy transparency and root status was weak, declining trees having slightly lower RLD V (-20 %) and RTD V (-11 %). After a 1 year lag, during which the parameters were almost unaffected, BI and RLD V , together with tip density, tip vitality and mycorrhizal colonization, became the descriptors most representative of both decline class and thinning. Thinning of declining trees increased RLD V (+12 %) and RTD V (+32 %), but reduced tip mycorrhizal colonization and vitality over time compared with non-thinned trees, whereas the opposite occurred in healthy trees, together with a marked decrease in branching. After thinning, there was an initial reduction in the structure of the ectomycorrhizal community, although recovery occurred about 10 months later, regardless of decline severity. Decline causes losses of fine root length, and a moderate recovery can be achieved by thinning, allowing better soil exploration by oak roots. The close correlation between root vitality and mycorrhizal colonization and their deterioration after thinning indicates that decline does not benefit from reduced root competition

  13. Impedance of finite length resistive cylinder

    Directory of Open Access Journals (Sweden)

    S. Krinsky

    2004-11-01

    Full Text Available We determine the impedance of a cylindrical metal tube (resistor of radius a, length g, and conductivity σ 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, ka^{2}≪g, the impedance per unit length is accurately described by the well-known result for an infinite length tube with conductivity σ. In the transient regime, ka^{2}≫g, where the contribution of transition radiation arising from the discontinuity in conductivity is important, we derive an analytic expression for the impedance and compute the short-range wakefield. The analytic results are shown to agree with numerical evaluation of the impedance.

  14. FULL LENGTH RESEARCH ARTICLE Adamu & Babatunde (2008 ...

    African Journals Online (AJOL)

    Dr. Ahmed

    FULL LENGTH RESEARCH ARTICLE. Adamu & Babatunde (2008) SWJ:21-25. Comparative Studies On the Dying rate Migration. COMPARATIVE STUDIES ON DYEING RATE MIGRATION AND WASH FASTNESS PROPERTIES OF AZO DYES. DERIVED FROM 2-AMINOTHIAZOLE DERIVATIVES ON ACETATE FABRICS.

  15. Identification of amplified fragment length polymorphism (AFLP ...

    African Journals Online (AJOL)

    Identification of amplified fragment length polymorphism (AFLP) fragments linked to soybean mosaic virus resistance gene in Glycine soja and conversion to a sequence characterized amplified regions (SCAR) marker for rapid selection.

  16. Martian Length of Day Measurements from Rovers

    Science.gov (United States)

    Eubanks, T. M.; Bills, B.

    2012-06-01

    Changes in the Martian Length of Day (LOD) can be determined at a scientifically use level by a combination of regular (but not necessarily frequent) range and Doppler measurements from Earth and dead reckoning in a Kalman filter.

  17. Complementary DNA-amplified fragment length polymorphism ...

    African Journals Online (AJOL)

    Complementary DNA-amplified fragment length polymorphism (AFLP-cDNA) analysis of differential gene expression from the xerophyte Ammopiptanthus mongolicus in response to cold, drought and cold together with drought.

  18. Relationship between morphological and amplified fragment length ...

    African Journals Online (AJOL)

    Relationship between morphological and amplified fragment length polymorphism (AFLP) marker based genetic distance with heterosis in hot pepper (Capsicum annuum L.) SL Krishnamurthy, A Mohan Rao, K Madhavi Reddy, S Ramesh, Shailaja Hittalmani, Rao M. Gopinath ...

  19. Chord length distribution for a compound capsule

    International Nuclear Information System (INIS)

    Pitřík, Pavel

    2017-01-01

    Chord length distribution is a factor important in the calculation of ionisation chamber responses. This article describes Monte Carlo calculations of the chord length distribution for a non-convex compound capsule. A Monte Carlo code was set up for generation of random chords and calculation of their lengths based on the input number of generations and cavity dimensions. The code was written in JavaScript and can be executed in the majority of HTML viewers. The plot of occurrence of cords of different lengths has 3 peaks. It was found that the compound capsule cavity cannot be simply replaced with a spherical cavity of a triangular design. Furthermore, the compound capsule cavity is directionally dependent, which must be taken into account in calculations involving non-isotropic fields of primary particles in the beam, unless equilibrium of the secondary charged particles is attained. (orig.)

  20. 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...

  1. 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.

  2. 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.

  3. 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.

  4. The SME gauge sector with minimum length

    Energy Technology Data Exchange (ETDEWEB)

    Belich, H.; Louzada, H.L.C. [Universidade Federal do Espirito Santo, Departamento de Fisica e Quimica, Vitoria, ES (Brazil)

    2017-12-15

    We study the gauge sector of the Standard Model Extension (SME) with the Lorentz covariant deformed Heisenberg algebra associated to the minimum length. In order to find and estimate corrections, we clarify whether the violation of Lorentz symmetry and the existence of a minimum length are independent phenomena or are, in some way, related. With this goal, we analyze the dispersion relations of this theory. (orig.)

  5. Tourism and fashion: factors affecting trip length

    OpenAIRE

    Calderón García, María Haydeé; G. Gallarza, Martina; Fayos Gardó, Teresa; O'Sullivan, P.

    2016-01-01

    Tourism and shopping are closely related, and the influence of fashion shopping on a tourist's decision to travel is especially significant. The concept of cognitive and hedonic involvement enables us to relate the importance given to shopping by consumers of fashion products and of tourism services. This research analyses whether tourist involvement in fashion shopping has an impact on the length of their stay in a destination. In addition, it examines whether trip length is conditioned by t...

  6. Is nutrient uptake by plant roots sensitive to the rate of mass flow? Reappraisal of an old chestnut for spatially distributed root systems

    Science.gov (United States)

    McMurtrie, R. E.; Näsholm, T.

    2015-12-01

    Numerous modelling papers have considered the contribution of mass flow to nutrient uptake by a single plant root, but few have evaluated its contribution at the scale of an entire root system. We derive equations for nitrogen (N) influx per unit root surface area (J) and N uptake by a single root (U) as functions of soil nitrogen supply, root-length density (RLD) and the velocity of water at the root surface (vo). This model of N uptake by a single root can be used to evaluate N uptake by an entire root system if spatial distributions are known for soil N supply, root biomass and water-uptake velocity. In this paper we show that spatial distributions of RLD and vo can be estimated simultaneously under an optimisation hypothesis (MaxNup, McMurtrie et al. 2012), according to which total root mass and total water uptake are distributed vertically in order to maximise total N uptake. The MaxNup hypothesis leads to equations for optimal vertical profiles of RLD, vo, J and U, maximum rooting depth and the fraction of total available soil nitrogen taken up by the root system. Predicted values of vo are enhanced at depths where nitrogen influx per unit root surface area (J) is more sensitive to vo and diminished at depths where J is less sensitive to vo. Predicted vo is largest at the base of the root system where RLD is lowest, and is smallest in upper soil layers where RLD is highest. MaxNup thus predicts that water uptake will be distributed preferentially to soil depths where it will enhance nitrogen uptake U; this tendency will amplify the sensitivity of total N uptake to total water uptake, compared with strategies where vo is the same for all roots, or where vo is elevated for roots in upper soil layers. Reference McMurtrie RE, Iversen CM, Dewar RC, Medlyn BE, Näsholm T, Pepper DA, Norby RJ. 2012. Plant root distributions and nitrogen uptake predicted by a hypothesis of optimal root foraging. Ecology and Evolution 2: 1235-1250.

  7. Bruch´s membrane thickness in relationship to axial length.

    Directory of Open Access Journals (Sweden)

    Hai Xia Bai

    Full Text Available To assess a potential role of Bruch´s membrane (BM in the biomechanics of the eye, we measured its thickness and the density of retinal pigment epithelium (RPE cells in various ocular regions in eyes of varying axial length.Human globes, enucleated because of an ocular tumor or end-stage glaucoma were prepared for histological examination. Using light microscopy, the histological slides were histomorphometrically examined applying a digitized image analysis system.The study included 104 eyes with a mean axial length of 27.9±3.2 mm (range:22.6mm-36.5mm. In eyes without congenital glaucoma, BM was significantly thickest (P<0.001 at the ora serrata, followed by the posterior pole, the midpoint between equator and posterior pole (MBEPP, and finally the equator. BM thickness was not significantly correlated with axial length (ora serrata: P = 0.93; equator:P = 0.31; MBEPP:P = 0.15; posterior pole:P = 0.35. RPE cell density in the pre-equatorial region (P = 0.02; regression coefficient r = -0.24 and in the retro-equatorial region (P = 0.03; r = -0.22 decreased with longer axial length, while RPE cell density at the ora serrata (P = 0.35, the MBEPP (P = 0.06; r = -0.19 and the posterior pole (P = 0.38 was not significantly correlated with axial length. Highly myopic eyes with congenital glaucoma showed a tendency towards lower BM thickness and lower RPE cell density at all locations.BM thickness, in contrast to scleral and choroidal thickness, was independent of axial length in eyes without congenital glaucoma. In association with an axial elongation associated decrease in the RPE cell density in the midperiphery, the findings support the notion of a biomechanical role BM may play in the process of emmetropization/myopization.

  8. Mapping Optimal Charge Density and Length of ROMP-Based PTDMs for siRNA Internalization.

    Science.gov (United States)

    Caffrey, Leah M; deRonde, Brittany M; Minter, Lisa M; Tew, Gregory N

    2016-10-10

    A fundamental understanding of how polymer structure impacts internalization and delivery of biologically relevant cargoes, particularly small interfering ribonucleic acid (siRNA), is of critical importance to the successful design of improved delivery reagents. Herein we report the use of ring-opening metathesis polymerization (ROMP) methods to synthesize two series of guanidinium-rich protein transduction domain mimics (PTDMs): one based on an imide scaffold that contains one guanidinium moiety per repeat unit, and another based on a diester scaffold that contains two guanidinium moieties per repeat unit. By varying both the degree of polymerization and, in effect, the relative number of cationic charges in each PTDM, the performances of the two ROMP backbones for siRNA internalization were evaluated and compared. Internalization of fluorescently labeled siRNA into Jurkat T cells demonstrated that fluorescein isothiocyanate (FITC)-siRNA internalization had a charge content dependence, with PTDMs containing approximately 40 to 60 cationic charges facilitating the most internalization. Despite this charge content dependence, the imide scaffold yielded much lower viabilities in Jurkat T cells than the corresponding diester PTDMs with similar numbers of cationic charges, suggesting that the diester scaffold is preferred for siRNA internalization and delivery applications. These developments will not only improve our understanding of the structural factors necessary for optimal siRNA internalization, but will also guide the future development of optimized PTDMs for siRNA internalization and delivery.

  9. Privacy functions and wilderness recreation: Use density and length of stay effects on experience

    Science.gov (United States)

    David N. Cole; Troy E. Hall

    2010-01-01

    Privacy and its functions are desirable attributes of the human experience in wilderness areas, where outstanding opportunities for solitude is legally mandated. Privacy, the ability to choose how and when to interact and exchange information with other people, enhances opportunities for both personal growth and interaction with the wilderness environment. This study...

  10. Two aspects of thin film analysis: boron profile and scattering length density profile

    Energy Technology Data Exchange (ETDEWEB)

    Chen-Mayer, H.H. E-mail: chen-mayer@nist.gov; Lamaze, G.P.; Coakley, K.J.; Satija, S.K

    2003-06-01

    Boron/phosphorus-doped silicate glass (BPSG) thin films are widely used in microelectronic circuit devices. We employ two neutron techniques to investigate a 200-nm thick BPSG film: neutron depth profiling (NDP) and neutron reflectometry (NR) to obtain complementary information on the boron containing layer.

  11. Probability densities and Lévy densities

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler

    For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated.......For positive Lévy processes (i.e. subordinators) formulae are derived that express the probability density or the distribution function in terms of power series in time t. The applicability of the results to finance and to turbulence is briefly indicated....

  12. Growing correlation length on cooling below the onset of caging in a simulated glass-forming liquid

    DEFF Research Database (Denmark)

    Lačević, N.; Starr, F. W.; Schrøder, Thomas

    2002-01-01

    We present a calculation of a fourth-order, time-dependent density correlation function that measures higher-order spatiotemporal correlations of the density of a liquid. From molecular dynamics simulations of a glass-forming Lennard-Jones liquid, we find that the characteristic length scale...... of the dynamics of the liquid in the alpha-relaxation regime....

  13. Ultrasound Assessment of Cervical Length in Pregnancy

    Directory of Open Access Journals (Sweden)

    An-Shine Chao

    2008-09-01

    Full Text Available Cervical length in high-risk women for preterm birth has to be identified before early second trimester. Sequential evaluations lead to high predictive significance. The mean cervical length at 24 weeks is about 35 mm when measured by transvaginal ultrasound. A short cervix is defined as a cervix that is less than 25 mm and funneling, i.e. ballooning of the membranes into a dilated internal os, but with a closed external os. Factors such as short cervical length, uterine anomaly, previous cervical surgery, multiple gestation and positive fetal fibronectin results are associated with preterm delivery. Serial transvaginal ultrasound examinations during the early second trimester would provide longitudinal changes in the cervical length. The use of 17α-hydroxyprogesterone caproate and cerclage has shown to be beneficial in preventing preterm delivery. When combined with other predictors such as occiput position, parity, maternal age and body mass index, cervical length is a useful parameter for predicting the feasibility of labor induction and successful delivery.

  14. Length expectation values in quantum Regge calculus

    International Nuclear Information System (INIS)

    Khatsymovsky, V.M.

    2004-01-01

    Regge calculus configuration superspace can be embedded into a more general superspace where the length of any edge is defined ambiguously depending on the 4-tetrahedron containing the edge. Moreover, the latter superspace can be extended further so that even edge lengths in each the 4-tetrahedron are not defined, only area tensors of the 2-faces in it are. We make use of our previous result concerning quantization of the area tensor Regge calculus which gives finite expectation values for areas. Also our result is used showing that quantum measure in the Regge calculus can be uniquely fixed once we know quantum measure on (the space of the functionals on) the superspace of the theory with ambiguously defined edge lengths. We find that in this framework quantization of the usual Regge calculus is defined up to a parameter. The theory may possess nonzero (of the order of Planck scale) or zero length expectation values depending on whether this parameter is larger or smaller than a certain value. Vanishing length expectation values means that the theory is becoming continuous, here dynamically in the originally discrete framework

  15. Functional scoliosis caused by leg length discrepancy

    Science.gov (United States)

    Daniszewska, Barbara; Zolynski, Krystian

    2010-01-01

    Introduction Leg length discrepancy (LLD) causes pelvic obliquity in the frontal plane and lumbar scoliosis with convexity towards the shorter extremity. Leg length discrepancy is observed in 3-15% of the population. Unequalized lower limb length discrepancy leads to posture deformation, gait asymmetry, low back pain and discopathy. Material and methods In the years 1998-2006, 369 children, aged 5 to 17 years (209 girls, 160 boys) with LLD-related functional scoliosis were treated. An external or internal shoe lift was applied. Results Among 369 children the discrepancy of 0.5 cm was observed in 27, 1 cm in 329, 1.5 cm in 9 and 2 cm in 4 children. During the first follow-up examination, within 2 weeks, the adjustment of the spine to new static conditions was noted and correction of the curve in 316 examined children (83.7%). In 53 children (14.7%) the correction was observed later and was accompanied by slight low back pain. The time needed for real equalization of limbs was 3 to 24 months. The time needed for real equalization of the discrepancy was 11.3 months. Conclusions Leg length discrepancy equalization results in elimination of scoliosis. Leg length discrepancy < 2 cm is a static disorder; that is why measurements should be performed in a standing position using blocks of adequate thickness and the position of the posterior superior iliac spine should be estimated. PMID:22371777

  16. Density limits in Tokamaks

    International Nuclear Information System (INIS)

    Tendler, M.

    1984-06-01

    The energy loss from a tokamak plasma due to neutral hydrogen radiation and recycling is of great importance for the energy balance at the periphery. It is shown that the requirement for thermal equilibrium implies a constraint on the maximum attainable edge density. The relation to other density limits is discussed. The average plasma density is shown to be a strong function of the refuelling deposition profile. (author)

  17. Why Density Dependent Propulsion?

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    In 2004 Khoury and Weltman produced a density dependent cosmology theory they call the Chameleon, as at its nature, it is hidden within known physics. The Chameleon theory has implications to dark matter/energy with universe acceleration properties, which implies a new force mechanism with ties to the far and local density environment. In this paper, the Chameleon Density Model is discussed in terms of propulsion toward new propellant-less engineering methods.

  18. Nuclear Level Densities

    International Nuclear Information System (INIS)

    Grimes, S.M.

    2005-01-01

    Recent research in the area of nuclear level densities is reviewed. The current interest in nuclear astrophysics and in structure of nuclei off of the line of stability has led to the development of radioactive beam facilities with larger machines currently being planned. Nuclear level densities for the systems used to produce the radioactive beams influence substantially the production rates of these beams. The modification of level-density parameters near the drip lines would also affect nucleosynthesis rates and abundances

  19. Comparison of quantitative trait loci for rice yield, panicle length and ...

    Indian Academy of Sciences (India)

    2011-08-19

    Aug 19, 2011 ... [Liu T., Li L., Zhang Y., Xu C., Li X. and Xing Y. 2011 Comparison of quantitative trait loci for rice yield, panicle length and spikelet density across three connected populations. J. Genet. 90, 377–382]. Introduction. Enhancing crop yield is one of the top priorities in crop breeding programmes. Among various ...

  20. Effect of chain length on the adhesion behaviour of n-alkanethiol self ...

    Indian Academy of Sciences (India)

    are reported to be highly dependent on several physical factors such as chain length, packing density and phase state [8]. The use of unmodified tips offers the flexibility of retrieving separate information on the van der Waal's forces and capillary forces. In the present study, alkanethiol monolayers on highly oriented Au(1 1 ...

  1. Numerical scalings of the decay lengths in the scrape-off layer

    DEFF Research Database (Denmark)

    Militello, F.; Naulin, V; Nielsen, Anders Henry

    2013-01-01

    Numerical simulations of L-mode turbulence in the scrape-off layer (SOL) are used to construct power scaling laws for the characteristic decay lengths of the temperature, density and heat flux at the outer mid-plane. Most of the results obtained are in qualitative agreement with the experimental...

  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. Extending electronic length frequency analysis in R

    DEFF Research Database (Denmark)

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

    2017-01-01

    of the asymptotic length parameter (L-infinity) are found to have significant effects on parameter estimation error. An outlook provides context as to the significance of the R-based implementation for further testing and development, as well as the general relevance of the method for data-limited stock assessment.......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...... with known values, the accuracy of the soVBGF parameter estimation was evaluated. The results indicate that both optimisation approaches are capable of finding high scoring solutions, yet settings regarding the initial restructuring process for LFQ bin scoring (i.e. "moving average,") and the fixing...

  4. Resonance effects in neutron scattering lengths

    International Nuclear Information System (INIS)

    Lynn, J.E.

    1989-01-01

    The nature of neutron scattering lengths is described and the nuclear effects giving rise to their variation is discussed. Some examples of the shortcomings of the available nuclear data base, particularly for heavy nuclei, are given. Methods are presented for improving this data base, in particular for obtaining the energy variation of the complex coherent scattering length from long to sub-angstrom wave lengths from the available sources of slow neutron cross section data. Examples of this information are given for several of the rare earth nuclides. Some examples of the effect of resonances in neutron reflection and diffraction are discussed. This report documents a seminar given at Argonne National Laboratory in March 1989. 18 refs., 18 figs

  5. 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.

  6. Nuclear reactor with scrammable part length rod

    International Nuclear Information System (INIS)

    Bevilacqua, F.

    1979-01-01

    A new part length rod is provided. It may be used to control xenon induced power oscillations but to contribute to shutdown reactivity when a rapid shutdown of the reactor is required. The part length rod consists of a control rod with three regions. The lower control region is a longer weaker active portion separated from an upper stronger shorter poison section by an intermediate section which is a relative non-absorber of neutrons. The combination of the longer weaker control section with the upper high worth poison section permits the part length rod of this to be scrammed into the core when a reactor shutdown is required but also permits the control rod to be used as a tool to control power distribution in both the axial and radial directions during normal operation

  7. 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.

  8. New plasma diagnosis by coherence length spectroscopy

    International Nuclear Information System (INIS)

    Poolyarat, N.; Kim, Y.W.

    2008-01-01

    A new methodology and instrumentation have been developed for diagnosis of dense high temperature plasmas. In a plasma medium, collision processes shorten the optical coherence length at a given emission wavelength. By measuring the coherence length, the rate of collisions a radiating particle experiences can be determined. A map of the collision rates throughout the plasma can speak volumes about the atomic and thermal state of the plasma. Both the time-integrated and time-resolved interference fringes are obtained using emissions due to the transition between 3s 2 3p 5 ( 2 P o 3/2 )4p and 3s 2 3p 5 ( 2 P o 3/2 )7d. We have observed that the coherence length indeed decreases with increasing collision rate, and in addition, as a function of time as a result of cumulative collisions. The coherence length was found to be 4200±800 nm at 50 torr where the collision frequency is 2.14x10 11 s -1 , and 2400±130 nm at 140 torr where the collision frequency is 8.13x10 11 s -1 . We have also discovered that the coherence length varies with the direction of the viewing line of sight into the discharge plasma. The anisotropy results from the non-uniform structure in the discharge current, and this is further investigated by intentionally deforming the tip of the cathode. A photographic examination of both the cathode and the anode disc confirms the non-axis-symmetric structure of the plasma, which leads to the asymmetry in the plasma, in agreement with the angular dependence of the coherence length. (author)

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

    Science.gov (United States)

    Crandall, David Lynn [Idaho Falls, ID

    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.

  10. Cutting Whole Length or Partial Length of Internal Anal Sphincter in Managementof Fissure in Ano

    Directory of Open Access Journals (Sweden)

    Furat Shani Aoda

    2017-12-01

    Full Text Available A chronic anal fissure is a common painful perianal condition.The main operative procedure to treat this painful condition is a lateral internal sphincteretomy (LIS.The aim of study is to compare the outcome and complications of closed LIS up to the dentate line (whole length of internal sphincter or up to the fissure apex (partial length of internal sphincter in the treatment of anal fissure.It is a prospective comparativestudy including 100 patients with chronic fissure in ano. All patients assigned to undergo closed LIS. Those patients were randomly divided into two groups: 50 patients underwent LIS to the level of dentate line (whole length and other 50 patients underwent LIS to the level of fissure apex (partial length. Patients were followed up weekly in the 1st month, twice monthly in the second month then monthly   for next 2 months and finally after 1 year. There was satisfactory relief of pain in all patients in both groups & complete healing of the fissure occurred. Regarding post operative incontinence no major degree of incontinence occur in both group but minor degree of incontinence persists In 7 patients after whole length LIS after one year. In conclusion, both whole length & partial length LIS associated with improvement of pain, good chance of healing but whole length LIS associated with more chance of long term  flatus incontinence. Hence,we recommend partial length LIS as treatment forchronic anal fissure.

  11. Apparatus for fabricating continuous lengths of superconductor

    Science.gov (United States)

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

    2001-01-01

    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. Stride length: measuring its instantaneous value

    International Nuclear Information System (INIS)

    Campiglio, G C; Mazzeo, J R

    2007-01-01

    Human gait has been studied from different viewpoints: kinematics, dynamics, sensibility and others. Many of its characteristics still remain open to research, both for normal gait and for pathological gait. Objective measures of some of its most significant spatial/temporal parameters are important in this context. Stride length, one of these parameters, is defined as the distance between two consecutive contacts of one foot with ground. On this work we present a device designed to provide automatic measures of stride length. Its features make it particularly appropriate for the evaluation of pathological gait

  13. CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENTRATION LENGTH

    International Nuclear Information System (INIS)

    GROEBNER, R.J.; MAHDAVI, M.A.; LEONARD, A.W.; OSBORNE, T.H.; WOLF, N.S.; PORTER, G.D.; STANGEBY, P.C.; BROOKS, N.H.; COLCHIN, R.J.; HEIDBRINK, W.W.; LUCE, T.C.; MCKEE, G.R.; OWEN, L.W.; WANG, G.; WHYTE, D.G.

    2002-01-01

    OAK A271 CORRELATION OF H-MODE BARRIER WIDTH AND NEUTRAL PENTRATION LENGTH. Pedestal studies in DIII-D find a good correlation between the width of the region of steep gradient in the H-mode density and the neutral penetration length. These results are obtained by comparing experimental density profiles to the predictions of an analytic model for the profile, obtained from the particle continuity equations for electrons and deuterium atoms. In its range of validity (edge temperature between 40-500 eV), the analytic model quantitatively predicts the observed decrease of the width as the pedestal density increases, the observed strong increase of the gradient of the density as the pedestal density increases and the observation that L-mode and H-mode profiles with the same pedestal density have very similar shapes. The width of the density barrier, measured from the edge of the electron temperature barrier, is the lower limit for the observed width of the temperature barrier. These results support the hypothesis that particle fueling provides a dominant control for the size of the H-mode transport barrier

  14. A magnetic suspension system for measuring liquid density

    Directory of Open Access Journals (Sweden)

    Luz María Centeno González

    2013-01-01

    Full Text Available Density is a derived quantity of mass and length; it is defined as mass per volume unit and its SI unit is kg/m3. National metrology institutes have been designing and building their own magnetic suspension systems during the last 5 decades for making fluid density measurements; this has allowed them to carry out research into liquids and gases’ physical characteristics. This paper was aimed at designing and developing a magnetic suspension system for a magnetic balance used in determining liquid density to be used in CENAM’s metrology density laboratories.

  15. Enhancement of electric and magnetic wave fields at density gradients

    Directory of Open Access Journals (Sweden)

    A. Reiniusson

    2006-03-01

    Full Text Available We use Freja satellite data to investigate irregular small-scale density variations. The observations are made in the auroral region at about 1000-1700 km. The density variations are a few percent, and the structures are found to be spatial down to a scale length of a few ion gyroradii. Irregular density variations are often found in an environment of whistler mode/lower hybrid waves and we show that at the density gradients both the electric and magnetic wave fields are enhanced.

  16. Charge density glass from fictions to facts

    Energy Technology Data Exchange (ETDEWEB)

    Biljakovic, K. [Institute of Physics, Zagreb (Croatia)], E-mail: katica@ifs.hr; Staresinic, D.; Dominko, D. [Institute of Physics, Zagreb (Croatia); Lasjaunias, J.C. [Institut Neel, Grenoble (France)

    2009-03-01

    Thirty years ago Fukuyama [J. Phys. Soc. Jpn. 45 (1978) 1474] predicted a transition from charge density wave (CDW) state to the charge density glass (CDG) at a finite temperature as the consequence of the competition between the uniform commensurability pinning and the random impurity pinning. We present strong evidence that the CDG phase indeed exists as a generic feature of density wave systems. However, it arises from the competition of the random impurity pinning and the electrostatic intra-CDW interaction which tends to establish a uniform phase at low temperature. The glass transition occurs at the temperature at which the free carriers cannot efficiently screen the phase distortions. The characteristic length scale of the disorder, i.e. the size of the phase coherent domains, governs the glass properties.

  17. Charge density glass from fictions to facts

    International Nuclear Information System (INIS)

    Biljakovic, K.; Staresinic, D.; Dominko, D.; Lasjaunias, J.C.

    2009-01-01

    Thirty years ago Fukuyama [J. Phys. Soc. Jpn. 45 (1978) 1474] predicted a transition from charge density wave (CDW) state to the charge density glass (CDG) at a finite temperature as the consequence of the competition between the uniform commensurability pinning and the random impurity pinning. We present strong evidence that the CDG phase indeed exists as a generic feature of density wave systems. However, it arises from the competition of the random impurity pinning and the electrostatic intra-CDW interaction which tends to establish a uniform phase at low temperature. The glass transition occurs at the temperature at which the free carriers cannot efficiently screen the phase distortions. The characteristic length scale of the disorder, i.e. the size of the phase coherent domains, governs the glass properties

  18. Bond-length fluctuations in the copper oxide superconductors

    CERN Document Server

    Goodenough, J B

    2003-01-01

    Superconductivity in the copper oxides occurs at a crossover from localized to itinerant electronic behaviour, a transition that is first order. A spinodal phase segregation is normally accomplished by atomic diffusion; but where it occurs at too low a temperature for atomic diffusion, it may be realized by cooperative atomic displacements. Locally cooperative, fluctuating atomic displacements may stabilize a distinguishable phase lying between a localized-electron phase and a Fermi-liquid phase; this intermediate phase exhibits quantum-critical-point behaviour with strong electron-lattice interactions making charge transport vibronic. Ordering of the bond-length fluctuations at lower temperatures would normally stabilize a charge-density wave (CDW), which suppresses superconductivity. It is argued that in the copper oxide superconductors, crossover occurs at an optimal doping concentration for the formation of ordered two-electron/two-hole bosonic bags of spin S = 0 in a matrix of localized spins; the correl...

  19. 28 CFR 551.4 - Hair length.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Hair length. 551.4 Section 551.4 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Grooming § 551.4... Warden shall require an inmate with long hair to wear a cap or hair net when working in food service or...

  20. 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...

  1. 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

  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...

  3. 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

  4. 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.

  5. Link lengths and their growth powers

    International Nuclear Information System (INIS)

    Huh, Youngsik; No, Sungjong; Oh, Seungsang; Rawdon, Eric J

    2015-01-01

    For a certain infinite family F of knots or links, we study the growth power ratios of their stick number, lattice stick number, minimum lattice length and minimum ropelength compared with their minimum crossing number c(K) for every K∈F. It is known that the stick number and lattice stick number grow between the (1/2) and linear power of the crossing number, and minimum lattice length and minimum ropelength grow with at least the (3/4) power of crossing number (which is called the four-thirds power law). Furthermore, the minimal lattice length and minimum ropelength grow at most as O (c(K)[ln(c(K))] 5 ), but it is unknown whether any family exhibits superlinear growth. For any real number r between (1/2) and 1, we give an infinite family of non-splittable prime links in which the stick number and lattice stick number grow exactly as the rth power of crossing number. Furthermore for any real number r between (3/4) and 1, we give another infinite family of non-splittable prime links in which the minimum lattice length and minimum ropelength grow exactly as the rth power of crossing number. (paper)

  6. Complementary DNA-amplified fragment length polymorphism ...

    African Journals Online (AJOL)

    owner

    2011-05-09

    May 9, 2011 ... Complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) technology was used to analyze ... that 9 of the studied expressed sequence tags (ESTs) are related to protein modification, 12 ESTs are involved in the .... primers were used during the first strand synthesis of our cDNA synthesis ...

  7. Fetal Umbilical Cord Length and Associated Intrapatum ...

    African Journals Online (AJOL)

    Shoulder dystocia, hand prolapse in a transverse lying fetus, abruptio placentae and prolonged second stage of labour had shorter cords while fetal distress, cord prolapse and mecunium stained liquor had longer cords when compared with the mean umbilical cord length of the study population. Conclusion: Umbilical cord ...

  8. Comparison of the Effects of the Different Methods for Computing the Slope Length Factor at a Watershed Scale

    Directory of Open Access Journals (Sweden)

    Fu Suhua

    2013-09-01

    Full Text Available The slope length factor is one of the parameters of the Universal Soil Loss Equation (USLE and the Revised Universal Soil Loss Equation (RUSLE and is sometimes calculated based on a digital elevation model (DEM. The methods for calculating the slope length factor are important because the values obtained may depend on the methods used for calculation. The purpose of this study was to compare the difference in spatial distribution of the slope length factor between the different methods at a watershed scale. One method used the uniform slope length factor equation (USLFE where the effects of slope irregularities (such as slope gradient, etc. on soil erosion by water were not considered. The other method used segmented slope length factor equation(SSLFE which considered the effects of slope irregularities on soil erosion by water. The Arc Macro Language (AML Version 4 program for the revised universal soil loss equation(RUSLE.which uses the USLFE, was chosen to calculate the slope length factor. In a parallel analysis, the AML code of RUSLE Version 4 was modified according to the SSLFE to calculate the slope length factor. Two watersheds with different slope and gully densities were chosen. The results show that the slope length factor and soil loss using the USLFE method were lower than those using the SSLFE method, especially on downslopes watershed with more frequent steep slopes and higher gully densities. In addition, the slope length factor and soil loss calculated by the USLFE showed less spatial variation.

  9. Topographical length scales of hierarchical superhydrophobic surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Dhillon, P.K. [Department of Physics, Indian Institute of Technology Ropar, Nangal Road, Rupnagar, Punjab 140001 (India); Brown, P.S.; Bain, C.D.; Badyal, J.P.S. [Department of Chemistry, Science Laboratories, Durham University, Durham DH1 3LE, England (United Kingdom); Sarkar, S., E-mail: sarkar@iitrpr.ac.in [Department of Physics, Indian Institute of Technology Ropar, Nangal Road, Rupnagar, Punjab 140001 (India)

    2014-10-30

    Highlights: • Hydrophobic CF{sub 4} plasma fluorinated polybutadiene surfaces has been characterised using AFM. • Micro, Nano, and Micro + Nano topographies generated by altering plasma power and duration. • Dynamic scaling theory and FFT analysis used to characterize these surfaces quantitatively. • Roughnesses are different for different length scales of the surfaces considered. • Highest local roughness obtained from scaling analysis for shorter length scales of about 500 nm explains the superhydrophobicity for the Micro + Nano surface. - Abstract: The morphology of hydrophobic CF{sub 4} plasma fluorinated polybutadiene surfaces has been characterised using atomic force microscopy (AFM). Judicious choice of the plasma power and exposure duration leads to formation of three different surface morphologies (Micro, Nano, and Micro + Nano). Scaling theory analysis shows that for all three surface topographies, there is an initial increase in roughness with length scale followed by a levelling-off to a saturation level. At length scales around 500 nm, it is found that the roughness is very similar for all three types of surfaces, and the saturation roughness value for the Micro + Nano morphology is found to be intermediate between those for the Micro and Nano surfaces. Fast Fourier Transform (FFT) analysis has shown that the Micro + Nano topography comprises a hierarchical superposition of Micro and Nano morphologies. Furthermore, the Micro + Nano surfaces display the highest local roughness (roughness exponent α = 0.42 for length scales shorter than ∼500 nm), which helps to explain their superhydrophobic behaviour (large water contact angle (>170°) and low hysteresis (<1°))

  10. On the ratios of Arc lengths to chord lengths in real Banach spaces ...

    African Journals Online (AJOL)

    Two new moduli are introduced to study the ratios of arc lengths to chord lengths in Banach spaces. Basic properties of those two moduli and the relation between them are studied. The relation between those two moduli and some geometric properties, including uniform convexity, uniform nonsquareness, and uniform ...

  11. The Chain-Length Distribution in Subcritical Systems

    International Nuclear Information System (INIS)

    Nolen, Steven Douglas

    2000-01-01

    The individual fission chains that appear in any neutron multiplying system provide a means, via neutron noise analysis, to unlock a wealth of information regarding the nature of the system. This work begins by determining the probability density distributions for fission chain lengths in zero-dimensional systems over a range of prompt neutron multiplication constant (K) values. This section is followed by showing how the integral representation of the chain-length distribution can be used to obtain an estimate of the system's subcritical prompt multiplication (MP). The lifetime of the chains is then used to provide a basis for determining whether a neutron noise analysis will be successful in assessing the neutron multiplication constant, k, of the system in the presence of a strong intrinsic source. A Monte Carlo transport code, MC++, is used to model the evolution of the individual fission chains and to determine how they are influenced by spatial effects. The dissertation concludes by demonstrating how experimental validation of certain global system parameters by neutron noise analysis may be precluded in situations in which the system K is relatively low and in which realistic detector efficiencies are simulated

  12. Air shower density spectrum

    Science.gov (United States)

    Porter, M. R.; Foster, J. M.; Hodson, A. L.; Hazen, W. E.; Hendel, A. Z.; Bull, R. M.

    Results are presented of a measurement of the differential local density spectrum of extensive air showers at sea level using 1 sq m current-limited spark chambers. The 2 cm gap, Ne/He-filled discharge chambers with 6 mm thick 'Georgia-wired' glass faces, were mounted directly on the underside of a light, uniform, sandwich-panel roof. Separate runs with different trigger requirements were made. Low density spectra according to different counting criteria are presented in a graph. Another graph shows a differential local density spectrum. The results of the measurements are compared with previous measurements

  13. QTL-mapping in mink (Neovison vison) shows evidence for QTL for guard hair thickness, guard hair length and skin length

    DEFF Research Database (Denmark)

    Thirstrup, Janne Pia; Labouriau, Rodrigo; Guldbrandtsen, Bernt

    2011-01-01

    Fur quality in mink (Neovison vison) is a composite trait, consisting of e.g. guard hair length, guard hair thickness and density of wool. A genome wide QTL search was performed to detect QTL for fur quality traits in mink. Here we present the results of QTL analyses for guard hair length, guard...... hair thickness and density of wool. Data from an F2-cross was analysed across fourteen chromosomes using 100 microsatellites as markers with a spacing of approximately 20 cM. The two lines used for the F2-cross were Nordic wild mink and American short nap mink. In total 1,083 animals (21 wild type, 25...... short nap, 103 F1 and 934 F2) were marker typed and recorded for the three presented fur quality traits. For the QTL-analyses a regression analysis implemented in QTL Express software was used. Evidence was found for the existence of QTL for guard hair length, guard hair thickness and density of wool...

  14. Density functional theory

    International Nuclear Information System (INIS)

    Das, M.P.

    1984-07-01

    The state of the art of the density functional formalism (DFT) is reviewed. The theory is quantum statistical in nature; its simplest version is the well-known Thomas-Fermi theory. The DFT is a powerful formalism in which one can treat the effect of interactions in inhomogeneous systems. After some introductory material, the DFT is outlined from the two basic theorems, and various generalizations of the theorems appropriate to several physical situations are pointed out. Next, various approximations to the density functionals are presented and some practical schemes, discussed; the approximations include an electron gas of almost constant density and an electron gas of slowly varying density. Then applications of DFT in various diverse areas of physics (atomic systems, plasmas, liquids, nuclear matter) are mentioned, and its strengths and weaknesses are pointed out. In conclusion, more recent developments of DFT are indicated

  15. Bone mineral density test

    Science.gov (United States)

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis - BMD ... need to undress. This scan is the best test to predict your risk of fractures, especially of ...

  16. Low Density Supersonic Decelerators

    Data.gov (United States)

    National Aeronautics and Space Administration — The Low-Density Supersonic Decelerator project will demonstrate the use of inflatable structures and advanced parachutes that operate at supersonic speeds to more...

  17. Generation of Length Distribution, Length Diagram, Fibrogram, and Statistical Characteristics by Weight of Cotton Blends

    Directory of Open Access Journals (Sweden)

    B. Azzouz

    2007-01-01

    Full Text Available The textile fibre mixture as a multicomponent blend of variable fibres imposes regarding the proper method to predict the characteristics of the final blend. The length diagram and the fibrogram of cotton are generated. Then the length distribution, the length diagram, and the fibrogram of a blend of different categories of cotton are determined. The length distributions by weight of five different categories of cotton (Egyptian, USA (Pima, Brazilian, USA (Upland, and Uzbekistani are measured by AFIS. From these distributions, the length distribution, the length diagram, and the fibrogram by weight of four binary blends are expressed. The length parameters of these cotton blends are calculated and their variations are plotted against the mass fraction x of one component in the blend .These calculated parameters are compared to those of real blends. Finally, the selection of the optimal blends using the linear programming method, based on the hypothesis that the cotton blend parameters vary linearly in function of the components rations, is proved insufficient.

  18. 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...

  19. 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

  20. Separation of pathogenic bacteria by chain length.

    Science.gov (United States)

    Beech, Jason P; Ho, Bao Dang; Garriss, Geneviève; Oliveira, Vitor; Henriques-Normark, Birgitta; Tegenfeldt, Jonas O

    2018-02-13

    Using Deterministic Lateral Displacement devices optimized for sensitivity to particle length, we separate subpopulations of bacteria depending on known properties that affect their capability to cause disease (virulence). For the human bacterial pathogen Streptococcus pneumoniae, bacterial chain length and the presence of a capsule are known virulence factors contributing to its ability to cause severe disease. Separation of cultured pneumococci into subpopulations based on morphological type (single cocci, diplococci and chains) will enable more detailed studies of the role they play in virulence. Moreover, we present separation of mixed populations of almost genetically identical encapsulated and non-encapsulated pneumococcal strains in our device. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Electron attenuation lengths in fullerene and fullerides

    International Nuclear Information System (INIS)

    Li Hongnian; Wang Xiaoxiong; Ding Wangfeng

    2006-01-01

    Using X-ray photoemission measurements, we have determined the attenuation length of C 1s photoelectrons in C 60 film to be 21.5 A with the incident photon energy of Mg Kα radiation. The inelastic mean free path calculated with the TPP-2M algorithm coincides fairly well with the experimentally determined attenuation length, indicating the validity of the algorithm to fullerene and fullerides. The inelastic mean free paths for some fullerides, i.e. K 3 C 60 , K 6 C 60 , Ba 4 C 60 , Sm 2.75 C 60 and Sm 6 C 60 are calculated to help the quantitative analyses of the photoemission spectra for these compounds

  2. Density of liquid Ytterbium

    International Nuclear Information System (INIS)

    Stankus, S.V.; Basin, A.S.

    1983-01-01

    Results are presented for measurements of the density of metallic ytterbium in the liquid state and at the liquid-solid phase transition. Based on the numerical data obtained, the coefficient of thermal expansion βZ of the liquid and the density discontinuity on melting deltarho/sub m/ are calculated. The magnitudes of βZ and deltarho/sub m/ for the heavy lanthanides are compared

  3. Population Density Modeling Tool

    Science.gov (United States)

    2012-06-26

    194 POPULATION DENSITY MODELING TOOL by Davy Andrew Michael Knott David Burke 26 June 2012 Distribution...MARYLAND NAWCADPAX/TR-2012/194 26 June 2012 POPULATION DENSITY MODELING TOOL by Davy Andrew Michael Knott David Burke...information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE 26

  4. The local mass density

    Science.gov (United States)

    Veeder, G. J.

    1974-01-01

    An improved mass-luminosity relation for faint main-sequence stars derived from recently revised masses for some faint double stars is presented. The total local mass density is increased to nearly 0.2 solar masses per cu pc. This estimate is as large as the mass density required by Oort's (1965) dynamical analysis of stellar motions perpendicular to the galactic plane if the mass is concentrated in a narrow layer.

  5. Magnetic fluctuations associated with density fluctuations in the tokamak edge

    International Nuclear Information System (INIS)

    Kim, Y.J.; Gentle, K.W.; Ritz, C.P.; Rhodes, T.L.; Bengtson, R.D.

    1989-01-01

    Electrostatic density and potential fluctuations occurring with high amplitude near the edge of a tokamak are correlated with components of the fluctuating magnetic field measured outside the limiter radius. It has been established that this turbulence is associated with fluctuations in current as well as density and potential. The correlation extends for substantial toroidal distances, but only if the probes are displaced approximately along field lines, consistent with the short coherence lengths poloidally but long coherence lengths parallel to the field which are characteristic for this turbulence. Furthermore, the correlation can be found only with density fluctuations measured inside the limiter radius; density fluctuations behind the limiter have no detectable magnetic concomitant for the toroidally spaced probes used here. (author). Letter-to-the-editor. 12 refs, 3 figs

  6. Measuring the orbit length of the Tevatron

    International Nuclear Information System (INIS)

    Kerns, C.; Kerns, Q.; Miller, H.

    1985-06-01

    The orbit length in the Tevatron was measured when coasting beam was first obtained. The method was time-of-flight, using a vernier phase comparison between beam pickup signals and a synthesizer sine wave. Some effort was spent making a stable phase detector so that it would not be a limiting factor. The results exhibited a repeatability of a few Hz at 53 MHz, corresponding to a mean radius measurement to 0.1 mm. 5 refs., 4 figs

  7. Measure it! fun with length and distance

    CERN Document Server

    First, Rachel

    2016-01-01

    Make math fun with Measure It! Fun photographs, colorful graphics, and simple text are used to teach young readers basic math concepts. From Metric System to Standard System this book will help kids develop the skills they need. A simple activity at the end of the book encourages kids to put length and distance to use! Aligned to Common Core standards and correlated to state standards. Sandcastle is an imprint of Abdo Publishing, a division of ABDO.

  8. 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....

  9. Asymptotic safety, emergence and minimal length

    International Nuclear Information System (INIS)

    Percacci, Roberto; Vacca, Gian Paolo

    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 sense in which asymptotic safety implies a minimal length. In doing so we also discuss possible signatures of asymptotic safety in scattering experiments.

  10. Negative Ion Density Fronts

    International Nuclear Information System (INIS)

    Igor Kaganovich

    2000-01-01

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas

  11. 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.

  12. The Effective Coherence Length in Anisotropic Superconductors

    International Nuclear Information System (INIS)

    Polturak, E.; Koren, G.; Nesher, O

    1999-01-01

    If electrons are transmitted from a normal conductor(N) into a superconductor(S), common wisdom has it that the electrons are converted into Cooper pairs within a coherence length from the interface. This is true in conventional superconductors with an isotropic order parameter. We have established experimentally that the situation is rather different in high Tc superconductors having an anisotropic order parameter. We used epitaxial thin film S/N bilayers having different interface orientations in order to inject carriers from S into N along different directions. The distance to which these carriers penetrate were determined through their effect on the Tc of the bilayers. We found that the effective coherence length is 20A only along the a or b directions, while in other directions we find a length of 250dr20A out of plane, and an even larger value for in-plane, off high symmetry directions. These observations can be explained using the Blonder-Tinkham-Klapwijk model adapted to anisotropic superconductivity. Several implications of our results on outstanding problems with high Tc junctions will be discussed

  13. Development of the Heated Length Correction Factor

    International Nuclear Information System (INIS)

    Park, Ho-Young; Kim, Kang-Hoon; Nahm, Kee-Yil; Jung, Yil-Sup; Park, Eung-Jun

    2008-01-01

    The Critical Heat Flux (CHF) on a nuclear fuel is defined by the function of flow channel geometry and flow condition. According to the selection of the explanatory variable, there are three hypotheses to explain CHF at uniformly heated vertical rod (inlet condition hypothesis, exit condition hypothesis, local condition hypothesis). For inlet condition hypothesis, CHF is characterized by function of system pressure, rod diameter, rod length, mass flow and inlet subcooling. For exit condition hypothesis, exit quality substitutes for inlet subcooling. Generally the heated length effect on CHF in exit condition hypothesis is smaller than that of other variables. Heated length is usually excluded in local condition hypothesis to describe the CHF with only local fluid conditions. Most of commercial plants currently use the empirical CHF correlation based on local condition hypothesis. Empirical CHF correlation is developed by the method of fitting the selected sensitive local variables to CHF test data using the multiple non-linear regression. Because this kind of method can not explain physical meaning, it is difficult to reflect the proper effect of complex geometry. So the recent CHF correlation development strategy of nuclear fuel vendor is making the basic CHF correlation which consists of basic flow variables (local fluid conditions) at first, and then the geometrical correction factors are compensated additionally. Because the functional forms of correction factors are determined from the independent test data which represent the corresponding geometry separately, it can be applied to other CHF correlation directly only with minor coefficient modification

  14. Determining multiple length scales in rocks

    Science.gov (United States)

    Song, Yi-Qiao; Ryu, Seungoh; Sen, Pabitra N.

    2000-07-01

    Carbonate reservoirs in the Middle East are believed to contain about half of the world's oil. The processes of sedimentation and diagenesis produce in carbonate rocks microporous grains and a wide range of pore sizes, resulting in a complex spatial distribution of pores and pore connectivity. This heterogeneity makes it difficult to determine by conventional techniques the characteristic pore-length scales, which control fluid transport properties. Here we present a bulk-measurement technique that is non-destructive and capable of extracting multiple length scales from carbonate rocks. The technique uses nuclear magnetic resonance to exploit the spatially varying magnetic field inside the pore space itself-a `fingerprint' of the pore structure. We found three primary length scales (1-100µm) in the Middle-East carbonate rocks and determined that the pores are well connected and spatially mixed. Such information is critical for reliably estimating the amount of capillary-bound water in the rock, which is important for efficient oil production. This method might also be used to complement other techniques for the study of shaly sand reservoirs and compartmentalization in cells and tissues.

  15. 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.

  16. Telomere length is associated with obesity parameters but with a gender difference.

    Science.gov (United States)

    Nordfjäll, Katarina; Eliasson, Mats; Stegmayr, Birgitta; Melander, Olle; Nilsson, Peter; Roos, Göran

    2008-12-01

    Cardiovascular disease (CVD) and obesity have been coupled to short telomere length in peripheral blood. The biological background to this observation is not obvious from the literature. In this study we have analyzed a large set of known risk factors for CVD in relation to telomere length in blood cells on a merged cohort of 989 individuals recruited in the Malmö Diet and Cancer Cohort (MDCC) and the Northern Sweden MONICA project. We found a significant or borderline association between obesity parameters and telomere length in women after age and center adjustments (BMI: r = -0.106, P = 0.021, weight: r = -0.087, P = 0.060, waist circumference: r = -0.099, P = 0.032, hip circumference: r = -0.128, P = 0.005). In men, a positive borderline correlation to high-density lipoprotein (HDL) (r = 0.111, P = 0.053) and a negative correlation to 2-h post-oral glucose-tolerance test (OGTT) was observed (r = -0.202, P = 0.045). In neither group any association was found between telomere length and cholesterol, serum triglycerides, serum low-density lipoprotein, plasma insulin, blood pressure, pulse pressure, or smoking habits. Our data indicate that telomere length is associated with an "obesity-phenotype" but only in women.

  17. Analytical calculation of chain length in ferrofluids

    Indian Academy of Sciences (India)

    the density of the dispersed particles with surfactant coating. In a FF, the dispersed nanoparticles experience both translational and rotational motion. The particles, under an external field, endure magnetic force-driven diffusion process. The overall change of the particle concentration is more important than the individual ...

  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. The effects of slope length and slope gradient on the size distributions of loess slides: Field observations and simulations

    Science.gov (United States)

    Qiu, Haijun; Cui, Peng; Regmi, Amar Deep; Hu, Sheng; Wang, Xingang; Zhang, Yuzhu

    2018-01-01

    In this study, we characterize and consider the effects of slope length and slope gradient on the size distributions of loess slides. To carry out this study, we employ data on 275 loess slides within Zhidan County, Central Loess Plateau, China. These data were collected in the field and supplemented by the interpretation of remote sensing images. Both the field observations and slope stability analysis show that loess slide size increases with the slope length. Slide sizes is significantly correlated with slope length, showing a power law relationship in both cases. However, the simulation results show that slope gradient is not associated with loess slide size. The main part of the link between slope gradient and slide size seen in the observations is only apparent, as indicated by the strong connection between slope gradient and length. Statistical analysis of the field observations reveals that slope gradient decreases with increasing slope length, and this correlation interferes with the potential relationship between landslide sizes and slope gradient seen in the field observations. In addition, the probability densities of the areas of loess slides occurring on slopes of different slope lengths are determined using kernel density estimation. This analysis shows that slope length controls the rollover of the frequency-size distribution of loess slides. The scaling exponent increases with slope length.

  20. High Density Matter

    Directory of Open Access Journals (Sweden)

    Stone J.R.

    2013-12-01

    Full Text Available The microscopic composition and properties of matter at super-saturation densities have been the subject of intense investigation for decades. The scarcity of experimental and observational data has led to the necessary reliance on theoretical models. There remains great uncertainty in these models which, of necessity, have to go beyond the over-simple assumption that high density matter consists only of nucleons and leptons. Heavy strange baryons, mesons and quark matter in different forms and phases have to be included to fulfil basic requirements of fundamental laws of physics. In this contribution latest developments in construction of the Equation of State (EoS of high-density matter at zero and finite temperature assuming different composition of matter will be discussed. Critical comparison of model EoS with available experimental data from heavy ion collisions and observations on neutron stars, including gravitational mass, radii and cooling patterns and data on X-ray burst sources and low mass X-ray binaries are made. Fundamental differences between the EoS of low-density, high temperature matter, such as is created in heavy ion collisions and of high-density, low temperature compact objects is discussed.

  1. Air method measurements of apple vessel length distributions with improved apparatus and theory.

    Science.gov (United States)

    Cohen, Shabtai; Bennink, John; Tyree, Mel

    2003-08-01

    Studies showing that rootstock dwarfing potential is related to plant hydraulic conductance led to the hypothesis that xylem properties are also related. Vessel length distribution and other properties of apple wood from a series of varieties were measured using the 'air method' in order to test this hypothesis. Apparatus was built to measure and monitor conductivity to air of fresh wood segments of different lengths. Theory for determining vessel length distribution was improved to give a single parameter uni-modal vessel length probability density function. The function, derived by combining the exponential extinction (with extinction coefficient k) of wood conductivity to air (C) as wood length (x) increases (i.e. C=Co exp (-kx)) with the differential double difference formula, is Px=xxk2 exp (-kx), where Px is the fraction of vessels of length x. The main parameter of the distribution, k, was found to be the inverse of the mode of the distribution, i.e. the most common vessel length, Lo. Lo for ten apple rootstock and scion varieties varied from 5.6+/-0.1 cm (+/-SE) for MM.111 to 9.0+/-1.0 for Prunifolia (P <0.05). Average maximum vessel length was approximately 50 cm, and differences were not significant. Effective vessel radii ranged from 14 for Prunifolia to 24.3+/-0.7 micro m for M.26, with standard errors less than 12% of the mean. Specific conductivity of a 15 cm wood segment ranged from 2x109-4) to 1.6+/-0.2x10(-2) dm3 s(-1) kPa(-1) m(-1) for maruba and M.26, respectively, with standard errors up to 63% of the mean. Vessel density at the air entry point ranged from 18+/-3 to 42+/-6 vessels mm-2 for M.26 and MM.106, respectively, with standard errors as high as 89% of the mean. It was concluded that there is no general relationship between the wood properties investigated and rootstock size class, and that plasticity increases from vessel lengths to radii to specific conductivity and vessel densities.

  2. CRISS power spectral density

    International Nuclear Information System (INIS)

    Vaeth, W.

    1979-04-01

    The correlation of signal components at different frequencies like higher harmonics cannot be detected by a normal power spectral density measurement, since this technique correlates only components at the same frequency. This paper describes a special method for measuring the correlation of two signal components at different frequencies: the CRISS power spectral density. From this new function in frequency analysis, the correlation of two components can be determined quantitatively either they stem from one signal or from two diverse signals. The principle of the method, suitable for the higher harmonics of a signal as well as for any other frequency combinations is shown for the digital frequency analysis technique. Two examples of CRISS power spectral densities demonstrates the operation of the new method. (orig.) [de

  3. Neutron chain length distributions in subcritical systems

    International Nuclear Information System (INIS)

    Nolen, S.D.; Spriggs, G.

    1999-01-01

    In this paper, the authors present the results of the chain-length distribution as a function of k in subcritical systems. These results were obtained from a point Monte Carlo code and a three-dimensional Monte Carlo code, MC++. Based on these results, they then attempt to explain why several of the common neutron noise techniques, such as the Rossi-α and Feynman's variance-to-mean techniques, are difficult to perform in highly subcritical systems using low-efficiency detectors

  4. Long Length Contaminated Equipment Maintenance Plan

    International Nuclear Information System (INIS)

    ESVELT, C.A.

    2000-01-01

    The purpose of this document is to provide the maintenance requirements of the Long Length Contaminated Equipment (LLCE) trailers and provide a basis for the maintenance frequencies selected. This document is applicable to the LLCE Receiver trailer and Transport trailer assembled by Mobilized Systems Inc. (MSI). Equipment used in conjunction with, or in support of, these trailers is not included. This document does not provide the maintenance requirements for checkout and startup of the equipment following the extended lay-up status which began in the mid 1990s. These requirements will be specified in other documentation

  5. 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.

  6. Length Scales in Bayesian Automatic Adaptive Quadrature

    Science.gov (United States)

    Adam, Gh.; Adam, S.

    2016-02-01

    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.

  7. 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...

  8. Holographic magnetisation density waves

    Energy Technology Data Exchange (ETDEWEB)

    Donos, Aristomenis [Centre for Particle Theory and Department of Mathematical Sciences, Durham University,Stockton Road, Durham, DH1 3LE (United Kingdom); Pantelidou, Christiana [Departament de Fisica Quantica i Astrofisica & Institut de Ciencies del Cosmos (ICC),Universitat de Barcelona,Marti i Franques 1, 08028 Barcelona (Spain)

    2016-10-10

    We numerically construct asymptotically AdS black brane solutions of D=4 Einstein theory coupled to a scalar and two U(1) gauge fields. The solutions are holographically dual to d=3 CFTs in a constant external magnetic field along one of the U(1)’s. Below a critical temperature the system’s magnetisation density becomes inhomogeneous, leading to spontaneous formation of current density waves. We find that the transition can be of second order and that the solutions which minimise the free energy locally in the parameter space of solutions have averaged stressed tensor of a perfect fluid.

  9. Nuclear level density

    International Nuclear Information System (INIS)

    Cardoso Junior, J.L.

    1982-10-01

    Experimental data show that the number of nuclear states increases rapidly with increasing excitation energy. The properties of highly excited nuclei are important for many nuclear reactions, mainly those that go via processes of the compound nucleus type. In this case, it is sufficient to know the statistical properties of the nuclear levels. First of them is the function of nuclear levels density. Several theoretical models which describe the level density are presented. The statistical mechanics and a quantum mechanics formalisms as well as semi-empirical results are analysed and discussed. (Author) [pt

  10. Rational Water and Nitrogen Management Improves Root Growth, Increases Yield and Maintains Water Use Efficiency of Cotton under Mulch Drip Irrigation

    Directory of Open Access Journals (Sweden)

    Hongzhi Zhang

    2017-05-01

    Full Text Available There is a need to optimize water-nitrogen (N applications to increase seed cotton yield and water use efficiency (WUE under a mulch drip irrigation system. This study evaluated the effects of four water regimes [moderate drip irrigation from the third-leaf to the boll-opening stage (W1, deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W2, pre-sowing and moderate drip irrigation from the third-leaf to the boll-opening stage (W3, pre-sowing and deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W4] and N fertilizer at a rate of 520 kg ha-1 in two dressing ratios [7:3 (N1, 2:8 (N2] on cotton root morpho-physiological attributes, yield, WUE and the relationship between root distribution and dry matter production. Previous investigations have shown a strong correlation between root activity and water consumption in the 40–120 cm soil layer. The W3 and especially W4 treatments significantly increased root length density (RLD, root volume density (RVD, root mass density (RMD, and root activity in the 40–120 cm soil layer. Cotton RLD, RVD, RMD was decreased by 13.1, 13.3, and 20.8%, respectively, in N2 compared with N1 at 70 days after planting (DAP in the 0–40 cm soil layer. However, root activity in the 40–120 cm soil layer at 140 DAP was 31.6% higher in N2 than that in N1. Total RMD, RLD and root activity in the 40–120 cm soil were significantly and positively correlated with shoot dry weight. RLD and root activity in the 40–120 cm soil layer was highest in the W4N2 treatments. Therefore increased water consumption in the deep soil layers resulted in increased shoot dry weight, seed cotton yield and WUE. Our data can be used to develop a water-N management strategy for optimal cotton yield and high WUE.

  11. Blood capillary length estimation from three-dimensional microscopic data by image analysis and stereology.

    Science.gov (United States)

    Kubínová, Lucie; Mao, Xiao Wen; Janáček, Jiří

    2013-08-01

    Studies of the capillary bed characterized by its length or length density are relevant in many biomedical studies. A reliable assessment of capillary length from two-dimensional (2D), thin histological sections is a rather difficult task as it requires physical cutting of such sections in randomized directions. This is often technically demanding, inefficient, or outright impossible. However, if 3D image data of the microscopic structure under investigation are available, methods of length estimation that do not require randomized physical cutting of sections may be applied. Two different rat brain regions were optically sliced by confocal microscopy and resulting 3D images processed by three types of capillary length estimation methods: (1) stereological methods based on a computer generation of isotropic uniform random virtual test probes in 3D, either in the form of spatial grids of virtual "slicer" planes or spherical probes; (2) automatic method employing a digital version of the Crofton relations using the Euler characteristic of planar sections of the binary image; and (3) interactive "tracer" method for length measurement based on a manual delineation in 3D of the axes of capillary segments. The presented methods were compared in terms of their practical applicability, efficiency, and precision.

  12. Sorghum cobalt analysis on not determined wave length with atomic ...

    African Journals Online (AJOL)

    This study was to know the better wave length on measuring cobalt content in forage sorghum hybrid (Sorghum bicolor) with an atomic absorption spectrophotometer. The analysis was on background correction mode with three wave lengths; 240.8, 240.7 (determined wave length or recommended wave length) and 240.6 ...

  13. Continuous Measurement Of Mass Density Of Yarn

    Science.gov (United States)

    Hinkley, Jeffrey A.; Marchello, Joseph M.; Johnston, John D.

    1993-01-01

    Prototype instrument provides measurement data from which one computes mass density of strand of yarn. Includes fixtures placing known length of yarn under known tension across fixed and movable support. Transverse vibrations induced in yarn by moving movable support up and down. Source of light illuminates photodetector at midlength of yarn, and photodetector senses repeated shadowing caused by vibration of yarn through light, thereby measuring vibrations. Also used for continuous real-time monitoring of such yarn-manufacturing processes as coating or impregnation.

  14. Smith Purcell Radiation Bunch-Length Measurement

    CERN Document Server

    Korbly, Stephen; Marsh, Roark A; Temkin, Richard J

    2005-01-01

    Measurements of Coherent Smith-Purcell Radiation (SPR) were performed at the 17 GHz high-gradient accelerator built by Haimson Research Corporation at the MIT Plasma Science and Fusion Center. SPR is a promising radiation source because the radiation intensity is enhanced by the number of grating periods. The radiation produced obeys the SP resonance condition correlating the radiation frequency at each observation angle, allowing SPR to be exploited as a bunch-length measurement. For a 15 MeV 150 mA 125 ns beam in short and long pulse modes, bunch-lengths of 0.6 ps and 1 ps were measured with this method, respectively, with an error of ± 0.1 ps. Frequency measurements were also performed using a double Heterodyne system. Heterodyne measurements revealed frequency-locking, which gave a power level enhancement of 1000 at integer multiples of the Accelerator RF frequency. Frequencies up to 514 GHz were measured with a bandwidth of 25 MHz.

  15. Association between Snoring and Leukocyte Telomere Length.

    Science.gov (United States)

    Shin, Chol; Yun, Chang-Ho; Yoon, Dae Wui; Baik, Inkyung

    2016-04-01

    Data on the association between snoring and telomere length, an indicator of biological aging, are very limited. Moreover, no polysomnography (PSG) studies on this association in a general population have been conducted. Our study aimed to evaluate the association between snoring and leukocyte telomere length (LTL) using PSG and a questionnaire. A cross-sectional PSG study embedded in a population-based cohort from the Korean Genome Epidemiology Study was conducted in 2010-2013. During the same period, questionnaire-based interviews, blood collection, and relative LTL assays were conducted. A total of 887 Korean men and women aged 50-79 y with an apnea-hypopnea index (AHI) snoring during sleep (% time spent snoring) assessed by PSG was inversely associated with LTL even after adjusting for potential risk factors and AHI. In the linear regression association between tertiles of percentage of time spent snoring and log-transformed LTL, coefficient estimates (P value) were -0.076 (snoring status determined using PSG and questionnaire information, both primary snorers and those with mild sleep apnea (5 ≤ AHI snoring may influence telomere attrition independent of sleep apnea. © 2016 Associated Professional Sleep Societies, LLC.

  16. 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 ...

  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. 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

  19. Aberrant leukocyte telomere length in Birdshot Uveitis.

    Directory of Open Access Journals (Sweden)

    Nadia Vazirpanah

    Full Text Available Birdshot Uveitis (BU is an archetypical chronic inflammatory eye disease, with poor visual prognosis, that provides an excellent model for studying chronic inflammation. BU typically affects patients in the fifth decade of life. This suggests that it may represent an age-related chronic inflammatory disease, which has been linked to increased erosion of telomere length of leukocytes.To study this in detail, we exploited a sensitive standardized quantitative real-time polymerase chain reaction to determine the peripheral blood leukocyte telomere length (LTL in 91 genotyped Dutch BU patients and 150 unaffected Dutch controls.Although LTL erosion rates were very similar between BU patients and healthy controls, we observed that BU patients displayed longer LTL, with a median of log (LTL = 4.87 (= 74131 base pair compared to 4.31 (= 20417 base pair in unaffected controls (P<0.0001. The cause underpinning the difference in LTL could not be explained by clinical parameters, immune cell-subtype distribution, nor genetic predisposition based upon the computed weighted genetic risk score of genotyped validated variants in TERC, TERT, NAF1, OBFC1 and RTEL1.These findings suggest that BU is accompanied by significantly longer LTL.

  20. Electron heating caused by the ion-acoustic decay instability in a finite-length system

    International Nuclear Information System (INIS)

    Rambo, P.W.; Woo, W.; DeGroot, J.S.; Mizuno, K.

    1984-01-01

    The ion-acoustic decay instability is investigated for a finite-length plasma with density somewhat below the cutoff density of the electromagnetic driver (napprox.0.7n/sub c/). For this regime, the heating in a very long system can overpopulate the electron tail and cause linear saturation of the low phase velocity electron plasma waves. For a short system, the instability is nonlinearly saturated at larger amplitude by ion trapping. Absorption can be significantly increased by the large-amplitude ion waves. These results compare favorably with microwave experiments

  1. Neutronic analysis of a high power density hybrid reactor using ...

    Indian Academy of Sciences (India)

    in hexagonal geometry with ten rows of pitch length 1·25 cm in the radial direction. In the investigated blanket, selection of the potential structural materials for a high power density reactor is conducted on the basis of the following considerations. Among the candidate structural materials for fusion reactors, tungsten (W) has ...

  2. Density profile of terminally attached polymer chains

    International Nuclear Information System (INIS)

    Venema, P.; Odijk, T.

    1992-01-01

    Scaling theory hypothesizes a step-function profile for the segment density of polymer chains terminally attached to a planar wall. Using a self-consistent-field theory we give a perturbation analysis of the first-order correction to the step-function profile in order to gauge the impact of a possible tail. The new profile decays smoothly to zero without a discontinuity in the derivative (except near the wall). The segment density profile as scaled by the amplitude of the step-function profile has a tail that decays essentially as 1/βz*2, with β a dimensionless parameter and z* the distance from the wall scaled by the step length of the step-function profile. A scaling analysis would yield z*-4/3. 13 refs., 4 figs

  3. Measurements of electron density profiles using an angular filter refractometer

    Energy Technology Data Exchange (ETDEWEB)

    Haberberger, D., E-mail: dhab@lle.rochester.edu; Ivancic, S.; Hu, S. X.; Boni, R.; Barczys, M.; Craxton, R. S.; Froula, D. H. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14636 (United States)

    2014-05-15

    A novel diagnostic technique, angular filter refractometry (AFR), has been developed to characterize high-density, long-scale-length plasmas relevant to high-energy-density physics experiments. AFR measures plasma densities up to 10{sup 21} cm{sup −3} with a 263-nm probe laser and is used to study the plasma expansion from CH foil and spherical targets that are irradiated with ∼9 kJ of ultraviolet (351-nm) laser energy in a 2-ns pulse. The data elucidate the temporal evolution of the plasma profile for the CH planar targets and the dependence of the plasma profile on target radius for CH spheres.

  4. Density in Liquids.

    Science.gov (United States)

    Nesin, Gert; Barrow, Lloyd H.

    1984-01-01

    Describes a fourth-grade unit on density which introduces a concept useful in the study of chemistry and procedures appropriate to the chemistry laboratory. The hands-on activities, which use simple equipment and household substances, are at the level of thinking Piaget describes as concrete operational. (BC)

  5. density functional theory (DFT)

    Indian Academy of Sciences (India)

    Abstract. In the present investigation, interaction of ruthenium (Ru) atoms with fluorine (F) atoms was studied using the density functional theory utilizing B3LYP method. It was found that up to seven F atoms can bind to a single Ru atom which results in increase of electron affinities successively, reaching a peak value of ...

  6. South Molle Island Extension, Density, and Calcification Data for 1814 to 1983

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  7. Wheeler Reef Extension, Density, and Calcification Data for 1744 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  8. Yankee Reef Extension, Density, and Calcification Data for 1888 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  9. Conical Rocks Extension, Density, and Calcification Data for 1851 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  10. Burkitt Island Extension, Density, and Calcification Data for 1916 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  11. Flinders Reef Extension, Density, and Calcification Data for 1718 to 1991

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  12. Masthead Island Extension, Density, and Calcification Data for 1753 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  13. North Molle Island Extension, Density, and Calcification Data for 1831 to 1983

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  14. Abraham Reef Extension, Density, and Calcification Data for 1479 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  15. Red Wallis Island Extension, Density, and Calcification Data for 1860 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  16. Stonehaven Island Extension, Density, and Calcification Data for 1793 to 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  17. Otter Reef Extension, Density, and Calcification Data for 1792 to 1987

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  18. Magnetic Island Extension, Density, and Calcification Data for 1820 to 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  19. Great Palm Island Extension, Density, and Calcification Data for 1872 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  20. Hook Island Extension, Density, and Calcification Data for 1690 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  1. Brook Island Extension, Density, and Calcification Data for 1746 to 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  2. Rib Reef Extension, Density, and Calcification Data for 1853 to 1983

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  3. Havannah Island Extension, Density, and Calcification Data for 1583 to 1987

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  4. Britomart Reef Extension, Density, and Calcification Data for 1574 to 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  5. Sanctuary Reef Extension, Density, and Calcification Data for 1501 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  6. Low Isles Extension, Density, and Calcification Data for 1934 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  7. Lupton Island Extension, Density, and Calcification Data for 1818 to 1983

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  8. Scawfell Island Extension, Density, and Calcification Data for 1821 to 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  9. Darnley Island Extension, Density, and Calcification Data for 1788 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  10. Coombe Island Extension, Density, and Calcification Data for 1822 to 1987

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  11. Cid Harbour Island Extension, Density, and Calcification Data for 1816 to 1991

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  12. Agincourt Reef Extension, Density, and Calcification Data for 1779 to 1988

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  13. Pandora Reef Extension, Density, and Calcification Data for 1875 to 1982

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  14. Snapper Island Extension, Density, and Calcification Data for 1923 to 1984

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  15. Kurrimine Beach Extension, Density, and Calcification Data for 1771 to 1983

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  16. Stanley Reef Extension, Density, and Calcification Data for 1912 to 1985

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Extension, Density, and Calcification data from 35 Porites coral cores covering the entire length of the Great Barrier Reef, Australia. Data set contains 35...

  17. Bone mineral density of the coracoid process decreases with age.

    Science.gov (United States)

    Beranger, Jean Sébastien; Maqdes, Ali; Pujol, Nicolas; Desmoineaux, Pierre; Beaufils, Philippe

    2016-02-01

    Surgical options in the treatment of recurrent anterior shoulder instability are numerous. The Latarjet procedure is one of the most common procedures performed. It has been previously demonstrated that bone mineral density decreases with age. This reduction thus increases the risk of osteoporosis and osteoporosis-related iatrogenic, traumatic or pathological fractures. The objective of this study was to quantify the bone mineral density of the coracoid process in different age groups. The hypothesis was that mineral bone density of the coracoid process decreases with age. Using the hospital's electronic database, 60 patients who underwent a shoulder CT scan were randomly selected retrospectively. Four groups of 15 were formed with mean ages of 20, 30, 40 and 50 years. Bone density, length, width and thickness of the coracoid process 10 mm from the tip were measured four times by two different evaluators. Bone density was expressed in Hounsfield units (HU). The mean bone mineral density of the coracoid process significantly decreased with age (p < 0.0001). A lower but insignificant difference of bone mineral density was observed in females. A good inter- and intra-observer reliability was found for bone mineral density measurement of the coracoid process (0.67 and 0.7, respectively). The bone mineral density of the coracoid process diminishes with age, thus confirming our hypothesis. There is a good inter- and intra-observer reliability of our CT scan-based coracoid process bone mineral density measurement rendering it reproducible in daily clinical practice. IV.

  18. Density-dependent growth in invasive Lionfish (Pterois volitans.

    Directory of Open Access Journals (Sweden)

    Cassandra E Benkwitt

    Full Text Available Direct demographic density dependence is necessary for population regulation and is a central concept in ecology, yet has not been studied in many invasive species, including any invasive marine fish. The red lionfish (Pterois volitans is an invasive predatory marine fish that is undergoing exponential population growth throughout the tropical western Atlantic. Invasive lionfish threaten coral-reef ecosystems, but there is currently no evidence of any natural population control. Therefore, a manipulative field experiment was conducted to test for density dependence in lionfish. Juvenile lionfish densities were adjusted on small reefs and several demographic rates (growth, recruitment, immigration, and loss were measured throughout an 8-week period. Invasive lionfish exhibited direct density dependence in individual growth rates, as lionfish grew slower at higher densities throughout the study. Individual growth in length declined linearly with increasing lionfish density, while growth in mass declined exponentially with increasing density. There was no evidence, however, for density dependence in recruitment, immigration, or loss (mortality plus emigration of invasive lionfish. The observed density-dependent growth rates may have implications for which native species are susceptible to lionfish predation, as the size and type of prey that lionfish consume is directly related to their body size. The absence of density-dependent loss, however, contrasts with many native coral-reef fish species and suggests that for the foreseeable future manual removals may be the only effective local control of this invasion.

  19. Analysing the length of care episode after hip fracture: a nonparametric and a parametric Bayesian approach.

    Science.gov (United States)

    Riihimäki, Jaakko; Sund, Reijo; Vehtari, Aki

    2010-06-01

    Effective utilisation of limited resources is a challenge for health care providers. Accurate and relevant information extracted from the length of stay distributions is useful for management purposes. Patient care episodes can be reconstructed from the comprehensive health registers, and in this paper we develop a Bayesian approach to analyse the length of care episode after a fractured hip. We model the large scale data with a flexible nonparametric multilayer perceptron network and with a parametric Weibull mixture model. To assess the performances of the models, we estimate expected utilities using predictive density as a utility measure. Since the model parameters cannot be directly compared, we focus on observables, and estimate the relevances of patient explanatory variables in predicting the length of stay. To demonstrate how the use of the nonparametric flexible model is advantageous for this complex health care data, we also study joint effects of variables in predictions, and visualise nonlinearities and interactions found in the data.

  20. Magnetic penetration depth and correlation length in the superconductor with local pairing

    International Nuclear Information System (INIS)

    Czart, W.; Kostyrko, T.; Robaszkiewicz, S.

    1995-01-01

    Within the Hartree-Fock approximation (HFA) we calculate the London penetration depth λ and the electromagnetic correlation length ξ in the superconductor described by the Hubbard model with on-site attraction. We analyze the results as a function of electron density n and interaction, and discuss the differences in the n-dependence of λ and T C for the 2D SQ and 3D fcc lattices. ((orig.))

  1. Propulsion Physics Using the Chameleon Density Model

    Science.gov (United States)

    Robertson, Glen A.

    2011-01-01

    To grow as a space faring race, future spaceflight systems will require a new theory of propulsion. Specifically one that does not require mass ejection without limiting the high thrust necessary to accelerate within or beyond our solar system and return within a normal work period or lifetime. The Chameleon Density Model (CDM) is one such model that could provide new paths in propulsion toward this end. The CDM is based on Chameleon Cosmology a dark matter theory; introduced by Khrouy and Weltman in 2004. Chameleon as it is hidden within known physics, where the Chameleon field represents a scalar field within and about an object; even in the vacuum. The CDM relates to density changes in the Chameleon field, where the density changes are related to matter accelerations within and about an object. These density changes in turn change how an object couples to its environment. Whereby, thrust is achieved by causing a differential in the environmental coupling about an object. As a demonstration to show that the CDM fits within known propulsion physics, this paper uses the model to estimate the thrust from a solid rocket motor. Under the CDM, a solid rocket constitutes a two body system, i.e., the changing density of the rocket and the changing density in the nozzle arising from the accelerated mass. Whereby, the interactions between these systems cause a differential coupling to the local gravity environment of the earth. It is shown that the resulting differential in coupling produces a calculated value for the thrust near equivalent to the conventional thrust model used in Sutton and Ross, Rocket Propulsion Elements. Even though imbedded in the equations are the Universe energy scale factor, the reduced Planck mass and the Planck length, which relates the large Universe scale to the subatomic scale.

  2. Short Telomere Length and Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Madrid, Alexander Scheller; 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...... (telomerase RNA component), which code for proteins and RNA involved in telomere maintenance. We studied 105 055 individuals from Copenhagen; 17 235 of these individuals were diagnosed with ischemic heart disease between 1977 and 2013, and 66 618 had telomere length measured. For genetic studies, we further...

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

    Science.gov (United States)

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

    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.

  4. Tolman's length and limiting supersaturation of vapor

    Science.gov (United States)

    Alekseechkin, Nikolay V.

    2018-01-01

    The classical Kelvin formula for the equilibrium vapor pressure over a droplet of radius R is extended to small radii and vapor non-ideality, from where the limiting supersaturation condition is obtained by relating the point R = 0 to the value of limiting (spinodal) supersaturation of vapor. The analysis of different dependences of the Tolman length on radius, δ (R) , obeying this condition suggests that (i) the value of δ (0) is positive and the function δ (R) decreases with increasing radius; (ii) the curvature effect (the dependence of surface tension on radius) in the nucleation region is determined by the value of δ (0) . At the same time, this effect is weakly sensitive to the form of the function δ (R) and insensitive to its asymptotic value δ∞ .

  5. 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...... 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......: In the validation study, EI/BMR was significantly lower on 1st, 2nd and 3rd consecutive recording days compared to 4-7 recording days (P

  6. 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...... increased with the number of recording days and was minimum 10 % higher for 7 days compared to 4 days. The number of eating occasions per day and the number of reported food items per meal did not differ between 4 and 7 recording days. Conclusion: Reducing the recording period from 7 to 4 consecutive days...... did not change EI/BMR at group level. Still a study effect seemed to occur in the two population samples resulting in lower estimates of EI/BMR day 1-2. The proportion of consumers was higher with a 7-day recording. These results support a reporting period from 4-7 days....

  7. 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...... to reflect the accumulated burden of inflammation and oxidative stress occurring during the life course. We specifically aimed to address whether childhood constitutes a sensitive period and how much of the relation between stressful life events and TL is mediated through somatic and mental health, lifestyle...... (CRP), interleukin (IL)-6 and IL-10). Total number of stressful events experienced during the life course was not associated with TL. In terms of sensitive periods, we found that number of stressful events in childhood was associated with shorter TL (βper number stressful events in childhood=-0.02(SE...

  8. 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.

  9. Father Loss and Child Telomere Length.

    Science.gov (United States)

    Mitchell, Colter; McLanahan, Sara; Schneper, Lisa; Garfinkel, Irv; Brooks-Gunn, Jeanne; Notterman, Daniel

    2017-08-01

    Father loss during childhood has negative health and behavioral consequences, but the biological consequences are unknown. Our goal was to examine how father loss (because of separation and/or divorce, death, or incarceration) is associated with cellular function as estimated by telomere length. Data come from the 9-year follow-up of the Fragile Families and Child Wellbeing Study, a birth cohort study of children in 20 large American cities ( N = 2420). Principal measures are as follows: salivary telomere length (sTL), mother reports of father loss, and polymorphisms in genes related to serotonergic and dopaminergic signaling. At 9 years of age, children with father loss have significantly shorter telomeres (14% reduction). Paternal death has the largest association (16%), followed by incarceration (10%), and separation and/or divorce (6%). Changes in income partially mediate these associations (95% mediation for separation and/or divorce, 30% for incarceration, and 25% for death). Effects are 40% greater for boys and 90% greater for children with the most reactive alleles of the serotonin transporter genes when compared with those with the least reactive alleles. No differences were found by age at father loss or a child's race/ethnicity. Father loss has a significant association with children's sTL, with the death of a father showing the largest effect. Income loss explains most of the association between child sTL and separation and/or divorce but much less of the association with incarceration or death. This underscores the important role of fathers in the care and development of children and supplements evidence of the strong negative effects of parental incarceration. Copyright © 2017 by the American Academy of Pediatrics.

  10. Concept of formation length in radiation theory

    International Nuclear Information System (INIS)

    Baier, V.N.; Katkov, V.M.

    2005-01-01

    The features of electromagnetic processes are considered which connected with finite size of space region in which final particles (photon, electron-positron pair) are formed. The longitudinal dimension of the region is known as the formation length. If some external agent is acting on an electron while traveling this distance the emission process can be disrupted. There are different agents: multiple scattering of projectile, polarization of a medium, action of external fields, etc. The theory of radiation under influence of the multiple scattering, the Landau-Pomeranchuk-Migdal (LPM) effect, is presented. The probability of radiation is calculated with an accuracy up to 'next to leading logarithm' and with the Coulomb corrections taken into account. The integral characteristics of bremsstrahlung are given, it is shown that the effective radiation length increases due to the LPM effect at high energy. The LPM effect for pair creation is also presented. The multiple scattering influences also on radiative corrections in a medium (and an external field too) including the anomalous magnetic moment of an electron and the polarization tensor as well as coherent scattering of a photon in a Coulomb field. The polarization of a medium alters the radiation probability in soft part of spectrum. Specific features of radiation from a target of finite thickness include: the boundary photon emission, interference effects for thin target, multi-photon radiation. The theory predictions are compared with experimental data obtained at SLAC and CERN SPS. For electron-positron colliding beams following items are discussed: the separation of coherent and incoherent mechanisms of radiation, the beam-size effect in bremsstrahlung, coherent radiation and mechanisms of electron-positron creation

  11. A new approach for estimating the density of liquids.

    Science.gov (United States)

    Sakagami, T; Fuchizaki, K; Ohara, K

    2016-10-05

    We propose a novel approach with which to estimate the density of liquids. The approach is based on the assumption that the systems would be structurally similar when viewed at around the length scale (inverse wavenumber) of the first peak of the structure factor, unless their thermodynamic states differ significantly. The assumption was implemented via a similarity transformation to the radial distribution function to extract the density from the structure factor of a reference state with a known density. The method was first tested using two model liquids, and could predict the densities within an error of several percent unless the state in question differed significantly from the reference state. The method was then applied to related real liquids, and satisfactory results were obtained for predicted densities. The possibility of applying the method to amorphous materials is discussed.

  12. Density functional theory for polymeric systems in 2D.

    Science.gov (United States)

    Słyk, Edyta; Roth, Roland; Bryk, Paweł

    2016-06-22

    We propose density functional theory for polymeric fluids in two dimensions. The approach is based on Wertheim's first order thermodynamic perturbation theory (TPT) and closely follows density functional theory for polymers proposed by Yu and Wu (2002 J. Chem. Phys. 117 2368). As a simple application we evaluate the density profiles of tangent hard-disk polymers at hard walls. The theoretical predictions are compared against the results of the Monte Carlo simulations. We find that for short chain lengths the theoretical density profiles are in an excellent agreement with the Monte Carlo data. The agreement is less satisfactory for longer chains. The performance of the theory can be improved by recasting the approach using the self-consistent field theory formalism. When the self-avoiding chain statistics is used, the theory yields a marked improvement in the low density limit. Further improvements for long chains could be reached by going beyond the first order of TPT.

  13. Simulation of density measurements in plasma wakefields using photon acceleration

    Directory of Open Access Journals (Sweden)

    Muhammad Firmansyah Kasim

    2015-03-01

    Full Text Available One obstacle in plasma accelerator development is the limitation of techniques to diagnose and measure plasma wakefield parameters. In this paper, we present a novel concept for the density measurement of a plasma wakefield using photon acceleration, supported by extensive particle in cell simulations of a laser pulse that copropagates with a wakefield. The technique can provide the perturbed electron density profile in the laser’s reference frame, averaged over the propagation length, to be accurate within 10%. We discuss the limitations that affect the measurement: small frequency changes, photon trapping, laser displacement, stimulated Raman scattering, and laser beam divergence. By considering these processes, one can determine the optimal parameters of the laser pulse and its propagation length. This new technique allows a characterization of the density perturbation within a plasma wakefield accelerator.

  14. Simulation of density measurements in plasma wakefields using photo acceleration

    CERN Document Server

    Kasim, Muhammad Firmansyah; Ceurvorst, Luke; Sadler, James; Burrows, Philip N; Trines, Raoul; Holloway, James; Wing, Matthew; Bingham, Robert; Norreys, Peter

    2015-01-01

    One obstacle in plasma accelerator development is the limitation of techniques to diagnose and measure plasma wakefield parameters. In this paper, we present a novel concept for the density measurement of a plasma wakefield using photon acceleration, supported by extensive particle in cell simulations of a laser pulse that copropagates with a wakefield. The technique can provide the perturbed electron density profile in the laser’s reference frame, averaged over the propagation length, to be accurate within 10%. We discuss the limitations that affect the measurement: small frequency changes, photon trapping, laser displacement, stimulated Raman scattering, and laser beam divergence. By considering these processes, one can determine the optimal parameters of the laser pulse and its propagation length. This new technique allows a characterization of the density perturbation within a plasma wakefield accelerator.

  15. The comparison between the length of vertical dimension of occlusion and the length of thumb on undergraduate Mongoloid students

    Directory of Open Access Journals (Sweden)

    Goh Li Teng

    2011-03-01

    Full Text Available The Thumb Rule of Leonardo da Vinci states that many proportions of the face show relationship with the length of thumb which is measured from the proximal tip of the proximal phalanx to the distal tip of the distal phalanx. Previous studies have shown that the length of the vertical dimension of occlusion (VDO is similar to the length of thumb of the Caucasoid race. The purpose of this study is to determine whether the length of VDO have correlations with the length of thumb among those of the Mongoloid race. This study took a survey method with the analytical cross-sectional approach. A total of 80 students of Faculty of Dentistry who have fulfilled all population criteria were randomly chosen to measure the length of VDO and the length of the thumb. Results analyzed with Student's t-test statistic revealed that there was a significant difference between males and females in the length of VDO and the length of the thumb, however, there was no significant difference between the length of VDO and the length of the thumb. There were very strong correlations (P<0.05 between the length of VDO and the length of the thumb. As a conclusion, the length of thumb can be suggested as an objective method to determine the length of VDO in this population.

  16. Quantal density functional theory

    CERN Document Server

    Sahni, Viraht

    2016-01-01

    This book deals with quantal density functional theory (QDFT) which is a time-dependent local effective potential theory of the electronic structure of matter. The treated time-independent QDFT constitutes a special case. In the 2nd edition, the theory is extended to include the presence of external magnetostatic fields. The theory is a description of matter based on the ‘quantal Newtonian’ first and second laws which is in terms of “classical” fields that pervade all space, and their quantal sources. The fields, which are explicitly defined, are separately representative of electron correlations due to the Pauli exclusion principle, Coulomb repulsion, correlation-kinetic, correlation-current-density, and correlation-magnetic effects. The book further describes Schrödinger theory from the new physical perspective of fields and quantal sources. It also describes traditional Hohenberg-Kohn-Sham DFT, and explains via QDFT the physics underlying the various energy functionals and functional derivatives o...

  17. Learning Grasp Affordance Densities

    DEFF Research Database (Denmark)

    Detry, Renaud; Kraft, Dirk; Kroemer, Oliver

    2011-01-01

    these and records their outcomes. When a satisfactory number of grasp data is available, an importance-sampling algorithm turns these into a grasp density. We evaluate our method in a largely autonomous learning experiment run on three objects of distinct shapes. The experiment shows how learning increases success...... rates. It also measures the success rate of grasps chosen to maximize the probability of success given reaching constraints....

  18. VULtURe snIPPets FRoM ARoUnD tHe WoRLD

    African Journals Online (AJOL)

    2007-05-03

    May 3, 2007 ... and broad-winged scavengers are making savage attacks on live cows, sheep and even horses, literally eating them alive. The phenomenon has surprised officials some of whom refuse to believe it, saying las Heras, president of the local chapter of a union called the Farmers and Ranchers. Coordinator.

  19. VULtURe snIPPets FRoM ARoUnD tHe WoRLD

    African Journals Online (AJOL)

    2007-05-03

    May 3, 2007 ... protect this incredible bird,” said Nava. AB. 821, the Ridley-Tree Condor Preservation. Act, will remove the number one threat to the survival of the endangered California. Condor, lead ammunition, by having hunters switch to a widely available, non- lead ammunition alternative when they hunt big game ...

  20. Toward a Redefinition of Density

    Science.gov (United States)

    Rapoport, Amos

    1975-01-01

    This paper suggests that in addition to the recent work indicating that crowding is a subjective phenomenon, an adequate definition of density must also include a subjective component since density is a complex phenomenon in itself. Included is a discussion of both physical density and perceived density. (Author/MA)

  1. Lifetime and Path Length of the Virtual Particle

    International Nuclear Information System (INIS)

    Lyuboshitz, V.L.; Lyuboshitz, V.V.

    2005-01-01

    The concepts of the lifetime and path length of a virtual particle are introduced. It is shown that, near the mass surface of the real particle, these quantities constitute a 4-vector. At very high energies, the virtual particle can propagate over considerable (even macroscopic) distances. The formulas for the lifetime and path length of an ultrarelativistic virtual electron in the process of bremsstrahlung in the Coulomb field of a nucleus are obtained. The lifetime and path length of the virtual photon at its conversion into an electron-positron pair are discussed. The connection between the path length of the virtual particle and the coherence length (formation length) is analyzed

  2. Quantitative analysis of cone photoreceptor distribution and its relationship with axial length, age, and early age-related macular degeneration.

    Directory of Open Access Journals (Sweden)

    Ryo Obata

    Full Text Available PURPOSE: It has not been clarified whether early age-related macular degeneration (AMD is associated with cone photoreceptor distribution. We used adaptive optics fundus camera to examine cone photoreceptors in the macular area of aged patients and quantitatively analyzed its relationship between the presence of early AMD and cone distribution. METHODS: Sixty cases aged 50 or older were studied. The eyes were examined with funduscopy and spectral-domain optical coherence tomography to exclude the eyes with any abnormalities at two sites of measurement, 2° superior and 5° temporal to the fovea. High-resolution retinal images with cone photoreceptor mosaic were obtained with adaptive optics fundus camera (rtx1, Imagine Eyes, France. After adjusting for axial length, cone packing density was calculated and the relationship with age, axial length, or severity of early AMD based on the age-related eye disease study (AREDS classification was analyzed. RESULTS: Patient's age ranged from 50 to 77, and axial length from 21.7 to 27.5 mm. Mean density in metric units and that in angular units were 24,900 cells/mm2, 2,170 cells/deg2 at 2° superior, and 18,500 cells/mm2, 1,570 cels/deg2 at 5° temporal, respectively. Axial length was significantly correlated with the density calculated in metric units, but not with that in angular units. Age was significantly correlated with the density both in metric and angular units at 2° superior. There was no significant difference in the density in metric and angular units between the eyes with AREDS category one and those with categories two or three. CONCLUSION: Axial length and age were significantly correlated with parafoveal cone photoreceptor distribution. The results do not support that early AMD might influence cone photoreceptor density in the area without drusen or pigment abnormalities.

  3. 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

  4. Density-dependent growth of the polychaete Diopatra aciculata

    Directory of Open Access Journals (Sweden)

    Milada Safarik

    2006-12-01

    Full Text Available Effects of intraspecific density on growth of the tube-building polychaete Diopatra aciculata (Onuphidae were examined over a three-month period within a marine worm aquaculture facility. Three polychaete densities (500, 1000 and 2000 worms/m2 were represented within triplicate 0.30 m2 boxes containing late juvenile D. aciculata, sandy sediment and recirculating seawater. Daily food ration per worm was held constant across all density levels. Total length, weight and number of segments were recorded for 20 polychaetes randomly removed from each of nine treatment boxes at weeks 1, 7 and 14. Mean daily growth was higher during weeks 1-7 than during weeks 7-14 for all growth variables at each density level. Polychaetes at the highest density level exhibited lower rates of growth and more broken and/or regenerating posterior segments than those at low density. High D. aciculata density was also associated with reduced dissolved oxygen concentrations and high polychaete mortality (20%. At medium polychaete density (1000/m2, D. aciculata exhibited low levels of apparent stress and high biomass return per unit area, both of which are important considerations in the aquaculture rearing of this species. We suggest that further studies focus on age- and size-related factors contributing to density effects on polychaete growth.

  5. Anomalous length dependence of the conductance of graphene nanoribbons with zigzag edges

    KAUST Repository

    Bilić, Ante

    2013-01-01

    Charge transport through two sets of symmetric graphene nanoribbons with zigzag shaped edges in a two-terminal device has been investigated, using density functional theory combined with the non-equilibrium Green\\'s function method. The conductance has been explored as a function of nanoribbon length, bias voltage, and the strength of terminal coupling. The set of narrower nanoribbons, in the form of thiolated linear acenes, shows an anomalous length dependence of the conductance, which at first exhibits a drop and a minimum, followed by an evident rise. The length trend is shown to arise because of a gradual transformation in the transport mechanism, which changes from being governed by a continuum of out-of-plane π type and in-plane state channels to being fully controlled by a single, increasingly more resonant, occupied π state channel. For the set of nanoribbons with a wider profile, a steady increase is observed across the whole length range, owing to the absence of the former transport mechanism. The predicted trends are confirmed by the inclusion of self-interaction correction in the calculations. For both sets of nanoribbons the replacement of the strongly coupling thiol groups by weakly bonding phenathroline has been found to cause a strong attenuation with the length and a generally low conductance. © 2013 American Institute of Physics.

  6. Relation between axial length and ocular parameters

    Directory of Open Access Journals (Sweden)

    Xue-Qiu Yang

    2013-09-01

    Full Text Available AIM: To investigatethe relation between axial length(AL, age and ocular parameters.METHODS: A total of 360 subjects(360 eyeswith emmetropia or myopia were recruited. Refraction, center corneal thickness(CCT, AL, intraocular pressure(IOPwere measured by automatic-refractor, Pachymeter, A-mode ultrasound and non-contact tonometer, respectively. Corneal curvature(CC, anterior chamber depth(ACDand white-to-white distance(WWDwere measured by Orbscan II. Three dimensional frequency domain coherent optical tomography(3D-OCTwas used to examine the retinal nerve fiber layer thickness(RNFLT. The Pearson correlation coefficient(rand multiple regression analysis were performed to evaluate the relationship between AL, age and ocular parameters.RESULTS: The average AL was 24.15±1.26mm. With elongation of the AL, spherical equivalent(SE(r=-0.742,Pr=-0.395, Pr=-0.374, Pr=0.411, Pr=0.099, P=0.060and WWD(r=0.061, P=0.252. There was also a significant correlation between AL and age(P=0.001, SE(PPPCONCLUSION: In longer eyes, there is a tendency toward myopia, a flatter cornea, a deeper ACD and a thinner RNFLT. Age is an influencing factor for the AL as well.

  7. Automated body hair counting and length measurement.

    Science.gov (United States)

    Vallotton, P; Thomas, N

    2008-11-01

    Hair loss or hair excess is a common condition. There is a growing need to quantitatively assess the success of interventions aimed at replenishing areas that lack hair or at removing hair from areas such as the back, the legs, or the arms. Non-invasive methods that do not require staining are highly desirable because the staining process itself may affect the efficacy of the treatment. We introduce a system based on a flatbed scanner and on novel and sensitive image analysis algorithms to count the number of hairs and their individual length. Additionally, a measure of hair visibility is introduced, which allows assessing objectively the severity of the condition. Our system is able to detect even hairs that are difficult to see to a human observer. It is robust to skin impurities or variations in the skin texture and colour. Scanner imaging ensures a sharp image over the whole field. The system analyses on the order of two images per minute, making it suitable for large clinical studies. Counts delivered by a human counter vs. the software were within 10% of each other (N=12). Based on our results, we expect that the software will be useful to a number of researchers investigating medical and cosmetic issues involving objective assessment of pilosity. The algorithm itself may be of use for other applications.

  8. Full length prototype SSC dipole test results

    International Nuclear Information System (INIS)

    Strait, J.; Brown, B.C.; Carson, J.

    1987-01-01

    Results are presented from tests of the first full length prototype SSC dipole magnet. The cryogenic behavior of the magnet during a slow cooldown to 4.5K and a slow warmup to room temperature has been measured. Magnetic field quality was measured at currents up to 2000 A. Averaged over the body field all harmonics with the exception of b 2 and b 8 are at or within the tolerances specified by the SSC Central Design Group. (The values of b 2 and b 8 result from known design and construction defects which will be be corrected in later magnets.) Using an NMR probe the average body field strength is measured to be 10.283 G/A with point to point variations on the order of one part in 1000. Data are presented on quench behavior of the magnet up to 3500 A (approximately 55% of full field) including longitudinal and transverse velocities for the first 250 msec of the quench

  9. 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.

  10. Molecular markers. Amplified fragment length polymorphism

    Directory of Open Access Journals (Sweden)

    Pržulj Novo

    2005-01-01

    Full Text Available Amplified Fragment Length Polymorphism molecular markers (AFLPs has been developed combining procedures of RFLPs and RAPDs molekular markers, i.e. the first step is restriction digestion of the genomic DNA that is followed by selective amplification of the restricted fragments. The advantage of the AFLP technique is that it allows rapid generation of a large number of reproducible markers. The reproducibility of AFLPs markers is assured by the use of restriction site-specific adapters and adapter-specific primers for PCR reaction. Only fragments containing the restriction site sequence plus the additional nucleotides will be amplified and the more selected nucleotides added on the primer sequence the fewer the number of fragments amplified by PCR. The amplified products are normally separated on a sequencing gel and visualized after exposure to X-ray film or by using fluorescent labeled primers. AFLP shave proven to be extremely proficient in revealing diversity at below the species level. A disadvantage of AFLP technique is that AFLPs are essentially a dominant marker system and not able to identify heterozygotes.

  11. Leukocyte Telomere Length in Postmenopausal Women.

    Science.gov (United States)

    Jones, Holly J; Janson, Susan L; Lee, Kathryn A

    To compare leukocyte telomere length (LTL) by race and describe demographic, health, and psychosocial factors associated with LTL in postmenopausal women. Descriptive study with comparative analyses and correlations. Data were collected at the University of California-San Francisco, San Francisco Clinical and Translational Science Institute. Thirty-nine African American and White postmenopausal women between 58 and 65 years of age (mean age = 61.3 ± 1.83 years). Measures included demographics, blood pressure, anthropometrics, scores on the Perceived Stress Scale and the Center for Epidemiologic Studies-Depression, and blood samples for LTL. African American women (n = 14) had greater PSS-10 and CES-D scores, greater blood pressure, and greater body mass index than White women (n = 25; p stress (p = .036) were related to shorter LTL. Findings from this small sample support the association between age and LTL. The association between perceived stress, number of children, and shorter LTL in postmenopausal women requires further research and replication of findings in a larger, more diverse sample. Copyright © 2017 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

  12. 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 ...

  13. Radiographic versus electronic root canal working length determination

    Directory of Open Access Journals (Sweden)

    Lumnije Kqiku

    2011-01-01

    Conclusions: The present ex vivo study showed that electronic root canal working length determination is not superior to radiographic methods. Both methods provided a good performance in determining the root canal working length.

  14. Performance of RC columns with partial length corrosion

    International Nuclear Information System (INIS)

    Wang Xiaohui; Liang Fayun

    2008-01-01

    Experimental and analytical studies on the load capacity of reinforced concrete (RC) columns with partial length corrosion are presented, where only a fraction of the column length was corroded. Twelve simply supported columns were eccentrically loaded. The primary variables were partial length corrosion in tensile or compressive zone and the corrosion level within this length. The failure of the corroded column occurs in the partial length, mainly developed from or located nearby or merged with the longitudinal corrosion cracks. For RC column with large eccentricity, load capacity of the column is mainly influenced by the partial length corrosion in tensile zone; while for RC column with small eccentricity, load capacity of the column greatly decreases due to the partial length corrosion in compressive zone. The destruction of the longitudinally mechanical integrality of the column in the partial length leads to this great reduction of the load capacity of the RC column

  15. Spark Length and the Van de Graaff Generator

    OpenAIRE

    Suthinand Jirakulpatana

    2007-01-01

    The maximum discharge spark length of a Van de Graaf generator as a function of belt speed was studied. It was found that the maximum spark length was proportional to the square root of the belt speed.

  16. Spark Length and the Van de Graaff Generator

    Directory of Open Access Journals (Sweden)

    Suthinand Jirakulpatana

    2007-06-01

    Full Text Available The maximum discharge spark length of a Van de Graaf generator as a function of belt speed was studied. It was found that the maximum spark length was proportional to the square root of the belt speed.

  17. 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...

  18. Density Distribution Sunflower Plots

    Directory of Open Access Journals (Sweden)

    William D. Dupont

    2003-01-01

    Full Text Available Density distribution sunflower plots are used to display high-density bivariate data. They are useful for data where a conventional scatter plot is difficult to read due to overstriking of the plot symbol. The x-y plane is subdivided into a lattice of regular hexagonal bins of width w specified by the user. The user also specifies the values of l, d, and k that affect the plot as follows. Individual observations are plotted when there are less than l observations per bin as in a conventional scatter plot. Each bin with from l to d observations contains a light sunflower. Other bins contain a dark sunflower. In a light sunflower each petal represents one observation. In a dark sunflower, each petal represents k observations. (A dark sunflower with p petals represents between /2-pk k and /2+pk k observations. The user can control the sizes and colors of the sunflowers. By selecting appropriate colors and sizes for the light and dark sunflowers, plots can be obtained that give both the overall sense of the data density distribution as well as the number of data points in any given region. The use of this graphic is illustrated with data from the Framingham Heart Study. A documented Stata program, called sunflower, is available to draw these graphs. It can be downloaded from the Statistical Software Components archive at http://ideas.repec.org/c/boc/bocode/s430201.html . (Journal of Statistical Software 2003; 8 (3: 1-5. Posted at http://www.jstatsoft.org/index.php?vol=8 .

  19. ?Linear Gas Jet with Tailored Density Profile"

    Energy Technology Data Exchange (ETDEWEB)

    KRISHNAN, Mahadevan

    2012-12-10

    Supersonic, highly collimated gas jets and gas-filled capillary discharge waveguides are two primary targets of choice for Laser Plasma Accelerators (LPA) . Present gas jets have lengths of only 2-4 mm at densities of 1-4E19 cm-3, sufficient for self trapping and electron acceleration to energies up to ~150 MeV. Capillary structures 3 cm long have been used to accelerate beams up to 1 GeV. Capillary discharges used in LPAs serve to guide the pump laser and optimize the energy gain. A wall-stabilized capillary discharge provides a transverse profile across the channel that helps guide the laser and combat diffraction. Gas injection via a fast nozzle at one end provides some longitudinal density control, to improve the coupling. Gas jets with uniform or controlled density profiles may be used to control electron bunch injection and are being integrated into capillary experiments to add tuning of density. The gas jet for electron injection has not yet been optimized. Our Ph-I results have provided the LPA community with an alternative path to realizing a 2-3GeV electron bunch using just a gas jet. For example, our slit/blade combination gives a 15-20mm long acceleration path with tunable density profile, serving as an alternative to a 20-mm long capillary discharge with gas injection at one end. In Ph-II, we will extend these results to longer nozzles, to see whether we can synthesize 30 or 40-mm long plasma channels for LPAs.

  20. Measurement of loose powder density

    International Nuclear Information System (INIS)

    Akhtar, S.; Ali, A.; Haider, A.; Farooque, M.

    2011-01-01

    Powder metallurgy is a conventional technique for making engineering articles from powders. Main objective is to produce final products with the highest possible uniform density, which depends on the initial loose powder characteristics. Producing, handling, characterizing and compacting materials in loose powder form are part of the manufacturing processes. Density of loose metallic or ceramic powder is an important parameter for die design. Loose powder density is required for calculating the exact mass of powder to fill the die cavity for producing intended green density of the powder compact. To fulfill this requirement of powder metallurgical processing, a loose powder density meter as per ASTM standards is designed and fabricated for measurement of density. The density of free flowing metallic powders can be determined using Hall flow meter funnel and density cup of 25 cm/sup 3/ volume. Density of metal powders like cobalt, manganese, spherical bronze and pure iron is measured and results are obtained with 99.9% accuracy. (author)

  1. Mapped DNA probes from Ioblolly pine can be used for restriction fragment length polymorphism mapping in other conifers

    Science.gov (United States)

    M.R. Ahuja; M.E. Devey; A.T. Groover; K.D. Jermstad; D.B Neale

    1994-01-01

    A high-density genetic map based on restriction fragment length polymorphisms (RFLPs) is being constructed for loblolly pine (Pinus taeda L.). Consequently, a large number of DNA probes from loblolly pine are potentially available for use in other species. We have used some of these DNA probes to detect RFLPs in 12 conifers and an angiosperm....

  2. Reduced rearing density increases postrelease migration success of Atlantic salmon (Salmo salar) smolts

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I; Näslund, Joacim

    2016-01-01

    during rearing in the hatchery. However, individuals reared at reduced density had less eroded dorsal fins and opercula relative to those from the high-density treatment. In the stream, the downstream migration success was 16% higher for fish reared at reduced density than for conspecifics kept at high-density......The overall aim of this study was to investigate the effect of rearing density on the post-release survival of Atlantic salmon (Salmo salar) smolts during seaward migration. Fish were either reared at conventional hatchery density or at one-third of conventional density. Three hundred one-year old...... smolts from each density treatment were individually tagged with passive integrated transponder (PIT) tags and released 3.2 km upstream of a stationary antenna array in a natural stream. There were no significant differences in length, body mass, or condition between fish from the two density treatments...

  3. Interplay between multiple length and time scales in complex ...

    Indian Academy of Sciences (India)

    Administrator

    micelles and enzymes, can span several orders of magnitude in length and time scales. The length and time scales of ... length and time scales is required in order to understand and predict structure and dynamics in such com- plex systems. This review .... The late 1980s saw the birth of femtochemistry with Ahmed Zewail ...

  4. Sorghum cobalt analysis on not determined wave length with atomic ...

    African Journals Online (AJOL)

    Jane

    2011-08-24

    Aug 24, 2011 ... right wave length for cobalt analysis with the atomic absorption spectrophotometer method. And this problem on wave length might exist also on the inductively coupled plasma spectroscopy (ICP) method. The wave length generally employed for cobalt determination is. 240.7 nm (Shapiro and Martin, 1988) ...

  5. Length weight relationship, food and feeding habits and condition ...

    African Journals Online (AJOL)

    Length weight relationship, food and feeding habit and condition factor of Synodontis melanoptera and Synodontis courtetti from Lower River were investigated. The results show that total length, weight and condition factor of S. melanoptera male ranged from 25.50-47.00cm, 100.00-955.00g and 0.39-1.82. Total length ...

  6. length-weight relationhip of freshwater wild fish species

    African Journals Online (AJOL)

    Dr Naeem

    2012-06-21

    Jun 21, 2012 ... Tor putitora. M. F. C. 2.76. 2.86. 2.85. Naeem et al. (2011) b = Slope; M = Male; F = Female; C = Combined Sex. Table 3. Morphometric relationships between total length (TL), fork length (FL) and standard length (SL) in cm for Mystus bleekeri collected from Nala Daik, Sialkot, Pakistan. Sex n. Equation.

  7. Random fractal characters and length uncertainty of the continental ...

    Indian Academy of Sciences (India)

    A coastline is a random fractal object in a geographical system whose length is uncertain. To determine the coastline length of a country or a region, the scaling region and fractal dimension of the coastline is first calculated, and then, the length of the coastline is measured using the scale at the lower limit or near the limit of ...

  8. Length-Weight Relationship and Condition Factor (K constant) of ...

    African Journals Online (AJOL)

    Abstract—Length-weight relationships and condition factors of Sparidae along the. Kenyan coast are unknown. This study investigated the length-weight relationship and condition factor of Dentex maroccanus Valenciennes, 1830, a sparid, found in. Malindi, Kenya, from June to August 2008. The length-weight coefficients ...

  9. LENGTH-WEIGHT RELATIONSHIP AND CONDITION FACTOR OF ...

    African Journals Online (AJOL)

    Data Collection and Analysis. The measurements of length (cm), weight (g) and the condition factor of individual fish sampled were recorded. The relationship between length and weight of the fish was examined by simple linear regression using WINKS software. The variations in the length-weight represented by 'b' were.

  10. 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

    2017-08-01

    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.

  11. The finite temperature density matrix and two-point correlations in the antiferromagnetic XXZ chain

    Science.gov (United States)

    Göhmann, Frank; Hasenclever, Nils P.; Seel, Alexander

    2005-10-01

    We derive finite temperature versions of integral formulae for the two-point correlation functions in the antiferromagnetic XXZ chain. The derivation is based on the summation of density matrix elements characterizing a finite chain segment of length m. On this occasion we also supply a proof of the basic integral formula for the density matrix presented in an earlier publication.

  12. On holographic entanglement density

    Science.gov (United States)

    Gushterov, Nikola I.; O'Bannon, Andy; Rodgers, Ronnie

    2017-10-01

    We use holographic duality to study the entanglement entropy (EE) of Conformal Field Theories (CFTs) in various spacetime dimensions d, in the presence of various deformations: a relevant Lorentz scalar operator with constant source, a temperature T , a chemical potential μ, a marginal Lorentz scalar operator with source linear in a spatial coordinate, and a circle-compactified spatial direction. We consider EE between a strip or sphere sub-region and the rest of the system, and define the "entanglement density" (ED) as the change in EE due to the deformation, divided by the sub-region's volume. Using the deformed CFTs above, we show how the ED's dependence on the strip width or sphere radius, L, is useful for characterizing states of matter. For example, the ED's small- L behavior is determined either by the dimension of the perturbing operator or by the first law of EE. For Lorentz-invariant renormalization group (RG) flows between CFTs, the "area theorem" states that the coefficient of the EE's area law term must be larger in the UV than in the IR. In these cases the ED must therefore approach zero from below as L→∞. However, when Lorentz symmetry is broken and the IR fixed point has different scaling from the UV, we find that the ED often approaches the thermal entropy density from above, indicating area theorem violation.

  13. Gluon density in nuclei

    International Nuclear Information System (INIS)

    Ayala, A.L.

    1996-01-01

    In this talk we present our detailed study (theory and numbers) on the shadowing corrections to the gluon structure functions for nuclei. Starting from rather controversial information on the nucleon structure function which is originated by the recent HERA data, we develop the Glauber approach for the gluon density in a nucleus based on Mueller formula and estimate the value of the shadowing corrections in this case. Then we calculate the first corrections to the Glauber approach and show that these corrections are big. Based on this practical observation we suggest the new evolution equation which takes into account the shadowing corrections and solve it. We hope to convince you that the new evolution equation gives a good theoretical tool to treat the shadowing corrections for the gluons density in a nucleus and, therefore, it is able to provide the theoretically reliable initial conditions for the time evolution of the nucleus-nucleus cascade. The initial conditions should be fixed both theoretically and phenomenologically before to attack such complicated problems as the mixture of hard and soft processes in nucleus-nucleus interactions at high energy or the theoretically reliable approach to hadron or/and parton cascades for high energy nucleus-nucleus interaction. 35 refs., 24 figs., 1 tab

  14. Estimation of ocular volume from axial length.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Logan, Nicola S

    2014-12-01

    To determine which biometric parameters provide optimum predictive power for ocular volume. Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions. Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV. Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Lengths may break privacy -- or how to check for equivalences with length

    OpenAIRE

    Cheval, Vincent; Cortier, Véronique; Plet, Antoine

    2013-01-01

    International audience; Security protocols have been successfully analyzed using symbolic models, where messages are represented by terms and protocols by processes. Privacy properties like anonymity or untraceability are typically expressed as equivalence between processes. While some decision procedures have been proposed for automatically deciding process equivalence, all existing approaches abstract away the information an attacker may get when observing the length of messages. In this pa...

  16. Modification of SOL profiles and fluctuations with line-average density and divertor flux expansion in TCV

    DEFF Research Database (Denmark)

    Vianello, N.; Tsui, C.; Theiler, C.

    2017-01-01

    A set of Ohmic density ramp experiments addressing the role of parallel connection length in modifying scrape off layer (SOL) properties has been performed on the TCV tokamak. The parallel connection length has been modified by varying the poloidal flux expansion fx. It will be shown that this mo......A set of Ohmic density ramp experiments addressing the role of parallel connection length in modifying scrape off layer (SOL) properties has been performed on the TCV tokamak. The parallel connection length has been modified by varying the poloidal flux expansion fx. It will be shown...... that this modification does not influence neither the detachment density threshold, nor the development of a flat SOL density profile which instead depends strongly on the increase of the core line average density. The modification of the SOL upstream profile, with the appearance of what is generally called a density...... shoulder, has been related to the properties of filamentary blobs. Blob size increases with density, without any dependence on the parallel connection length both in the near and far SOL. The increase of the density decay length, corresponding to a profile flattening, has been related to the variation...

  17. An investigation of pulsed high density plasmas

    International Nuclear Information System (INIS)

    Timmermans, C.J.

    1984-01-01

    In this thesis a wall-stabilized argon cascade arc is studied at values of pulsed pressure up to 14 bar and a pulsed current range up to 2200 A with a time duration of about 2 ms. The basic plasma is a CW cascade arc with a 5 mm diameter plasma column and a length of 90 mm, which operates at a 60 A DC current and at one atmosphere filling pressure. The author starts with an extensive summary of the CW arc investigations. After a brief introduction of the basic transport equations the mass equations of the constituent particles are treated using the extended collisional radiative model. The energy balance equations and the momentum balance are discussed. The electron density is determined from measurements of the continuum radiation. The final chapter contains the experimental results on the electron temperatures and electron densities in the pressure and current pulsed plasma. Attention is given to the deviations from local thermodynamic equilibrium values of the ground level densities of the different argon systems. (Auth.)

  18. Possible influence of the Kuramoto length in a photo-catalytic water splitting reaction revealed by Poisson-Nernst-Planck equations involving ionization in a weak electrolyte

    Science.gov (United States)

    Suzuki, Yohichi; Seki, Kazuhiko

    2018-03-01

    We studied ion concentration profiles and the charge density gradient caused by electrode reactions in weak electrolytes by using the Poisson-Nernst-Planck equations without assuming charge neutrality. In weak electrolytes, only a small fraction of molecules is ionized in bulk. Ion concentration profiles depend on not only ion transport but also the ionization of molecules. We considered the ionization of molecules and ion association in weak electrolytes and obtained analytical expressions for ion densities, electrostatic potential profiles, and ion currents. We found the case that the total ion density gradient was given by the Kuramoto length which characterized the distance over which an ion diffuses before association. The charge density gradient is characterized by the Debye length for 1:1 weak electrolytes. We discuss the role of these length scales for efficient water splitting reactions using photo-electrocatalytic electrodes.

  19. 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.

  20. Controlling the optical path length in turbid media using differential path-length spectroscopy: fiber diameter dependence

    NARCIS (Netherlands)

    Kaspers, O. P.; Sterenborg, H. J. C. M.; Amelink, A.

    2008-01-01

    We have characterized the path length for the differential path-length spectroscopy (DPS) fiber optic geometry for a wide range of optical properties and for fiber diameters ranging from 200 mu m to 1000 mu m. Phantom measurements show that the path length is nearly constant for scattering

  1. 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

  2. Hormonal Determinants of Mammographic Density

    National Research Council Canada - National Science Library

    Simpson, Jennifer K; Modugno, Francemary; Weissfeld, Joel L; Kuller, Lewis; Vogel, Victor; Constantino, Joseph P

    2005-01-01

    .... However, not all women on HRT will experience an increase in breast density. We propose a novel hypothesis to explain in part the individual variability in breast density seen among women on HRT...

  3. Neonatal Length Growth and Height at Two Years.

    Science.gov (United States)

    Goisbault, Manon; Simon, Laure; Hanf, Mathieu; Darmaun, Dominique; Rozé, Jean-Christophe; Flamant, Cyril

    2016-01-01

    Birth length is correlated to height at 2 years and is a predictor of adult height. However, little is known about the relationship between length growth during neonatal hospitalization and height at 2 years. The objective was to determine the relationship between length growth during neonatal hospitalization and height at 2 years in preterm infants. A total of 1,760 preterm infants of less than 35 weeks of gestational age were included. Neonatal length growth was defined by the difference between length Z-scores at discharge and at birth according to Olsen curves. We calculated the odds ratios (OR) before and after adjustment for the risk of being in the 1st quintile of the height Z-score at 2 years. Height at 2 years was positively associated with birth length (p years was significantly associated with birth length (adjusted OR = 0.43, 95% CI: 0.38-0.49, for one Z-score) and with neonatal length growth (adjusted OR = 0.66, 95% CI: 0.56-0.76, for one Z-score) before and after adjustment for perinatal variables. In addition to birth length, neonatal length growth was associated with height at 2 years. These findings point to the need for a close follow-up of the length of preterm infants during hospitalization, so as to start an early management of those patients. © 2016 S. Karger AG, Basel.

  4. Bunch length and the 102/90 degrees optics

    CERN Document Server

    Lamont, M

    1998-01-01

    The bunch length in LEP has become a cause for concern, particularly in the ramp to high energies. Short bunch lengths excite higher order modes which can cause heating of the inter-cavity bellows a nd may be picked up by antennae cables causing burning. The bunch length is also important from a cryogenics viewpoint; HOM losses go up with shorter bunches and more cryogenics power is required. Measurements made during 1997 show that it is strongly advisable to maintain bunch lengths above 9 mm particularly with high bunch currents. The use of a low emittance lattice such as 102/90 degr ees exacerbates the problem; because of the decreased momentum compaction the bunch lengths are naturally shorter. This paper quantifies the bunch lengths to be expected at various stages of ope ration in 1998 and presents recommendations for the avoidance of bunch lengths shorter than 9 mm.

  5. Automated path length and M56 measurements at Jefferson Lab

    International Nuclear Information System (INIS)

    Hardy, D.; Tang, J.; Legg, R.

    1997-01-01

    Accurate measurement of path length and path length changes versus momentum (M 56 ) are critical for maintaining minimum beam energy spread in the CEBAF (Continuous Electron Beam Accelerator Facility) accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The relative path length for each circuit of the beam (1256m) must be equal within 1.5 degrees of 1497 MHz RF phase. A relative path length measurement is made by measuring the relative phases of RF signals from a cavity that is separately excited for each pass of a 4.2 μs pulsed beam. This method distinguishes the path length to less than 0.5 path length error. The development of a VME based automated measurement system for path length and M 56 has contributed to faster machine setup time and has the potential for use as a feedback parameter for automated control

  6. Nuclear Energy Density Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Kortelainen, Erno M [ORNL; Lesinski, Thomas [ORNL; More, J. [Argonne National Laboratory (ANL); Nazarewicz, W. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Sarich, J. [Argonne National Laboratory (ANL); Schunck, N. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Stoitsov, M. V. [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL); Wild, S. [Argonne National Laboratory (ANL)

    2010-01-01

    We carry out state-of-the-art optimization of a nuclear energy density of Skyrme type in the framework of the Hartree-Fock-Bogoliubov (HFB) theory. The particle-hole and particle-particle channels are optimized simultaneously, and the experimental data set includes both spherical and deformed nuclei. The new model-based, derivative-free optimization algorithm used in this work has been found to be significantly better than standard optimization methods in terms of reliability, speed, accuracy, and precision. The resulting parameter set UNEDFpre results in good agreement with experimental masses, radii, and deformations and seems to be free of finite-size instabilities. An estimate of the reliability of the obtained parameterization is given, based on standard statistical methods. We discuss new physics insights offered by the advanced covariance analysis.

  7. Density functional theory

    International Nuclear Information System (INIS)

    Freyss, M.

    2015-01-01

    This chapter gives an introduction to first-principles electronic structure calculations based on the density functional theory (DFT). Electronic structure calculations have a crucial importance in the multi-scale modelling scheme of materials: not only do they enable one to accurately determine physical and chemical properties of materials, they also provide data for the adjustment of parameters (or potentials) in higher-scale methods such as classical molecular dynamics, kinetic Monte Carlo, cluster dynamics, etc. Most of the properties of a solid depend on the behaviour of its electrons, and in order to model or predict them it is necessary to have an accurate method to compute the electronic structure. DFT is based on quantum theory and does not make use of any adjustable or empirical parameter: the only input data are the atomic number of the constituent atoms and some initial structural information. The complicated many-body problem of interacting electrons is replaced by an equivalent single electron problem, in which each electron is moving in an effective potential. DFT has been successfully applied to the determination of structural or dynamical properties (lattice structure, charge density, magnetisation, phonon spectra, etc.) of a wide variety of solids. Its efficiency was acknowledged by the attribution of the Nobel Prize in Chemistry in 1998 to one of its authors, Walter Kohn. A particular attention is given in this chapter to the ability of DFT to model the physical properties of nuclear materials such as actinide compounds. The specificities of the 5f electrons of actinides will be presented, i.e., their more or less high degree of localisation around the nuclei and correlations. The limitations of the DFT to treat the strong 5f correlations are one of the main issues for the DFT modelling of nuclear fuels. Various methods that exist to better treat strongly correlated materials will finally be presented. (author)

  8. Continuous localization-delocalization transition at intermediate electron densities

    International Nuclear Information System (INIS)

    Neilson, D.; Thakur, J.S.

    1999-01-01

    We find in 2D electron layers in quantum transistors that the interplay between the electron correlations and their interactions with defects in the semiconductor substrate generates a continuous localisation-delocalisation transition for intermediate electron densities (5 ≤ r s≤ 9). We distinguish this transition from the discontinuous metal-insulator transition which is observed at lower electron densities (r s≥ 10). The approach we use is based on the behaviour of electrons at low densities. We take into account the interactions between electrons and also their interactions with disorder. We determine a zero temperature phase diagram of localised and delocalised states as a function of electron and impurity densities. The phase boundary of the continuous transition is determined by the localisation length of the electrons. Copyright (1999) CSIRO Australia

  9. Prediction of Separation Length of Turbulent Multiphase Flow Using Radiotracer and Computational Fluid Dynamics Simulation

    Directory of Open Access Journals (Sweden)

    S. Sugiharto1

    2013-04-01

    Full Text Available Multiphase flow modeling presents great challenges due to its extreme importance in various industrial and environmental applications. In the present study, prediction of separation length of multiphase flow is examined experimentally by injection of two kinds of iodine-based radiotracer solutions into a hydrocarbon transport pipeline (HCT having an inner diameter of 24 in (60,96 m. The main components of fluids in the pipeline are water 95%, crude oil 3% and gas 2%. A radiotracing experiment was carried out at the segment of pipe which is located far from branch points with assumptions that stratified flows in such segment were achieved. Two radiation detectors located at 80 and 100 m from injection point were used to generate residence time distribution (RTD curve resulting from injection of radiotracer solutions. Multiphase computational fluid dynamics (CFD simulations using Eulerian-Eulerian control volume and commercial CFD package Fluent 6.2 were employed to simulate separation length of multiphase flow. The results of study shows that the flow velocity of water is higher than the flow rate of crude oil in water-dominated system despite the higher density of water than the density of the crude oil. The separation length in multiphase flow predicted by Fluent mixture model is approximately 20 m, measured from injection point. This result confirms that the placement of the first radiation detector at the distance 80 m from the injection point was correct

  10. Anti-Caries Effects of Dental Adhesives Containing Quaternary Ammonium Methacrylates with Different Chain Lengths

    Directory of Open Access Journals (Sweden)

    Qi Han

    2017-06-01

    Full Text Available The objectives of this study were to investigate the effects of dental adhesives containing quaternary ammonium methacrylates (QAMs with different alkyl chain lengths (CL on ecological caries prevention in vitro. Five QAMs were synthesized with a CL = 3, 6, 9, 12, and 16 and incorporated into adhesives. Micro-tensile bond strength and surface charge density were used to measure the physical properties of the adhesives. The proportion change in three-species biofilms consisting of Streptococcus mutans, Streptococcus sanguinis, and Streptococcus gordonii was tested using the TaqMan real-time polymerase chain reaction. Lactic acid assay, MTT [3-(4,5-dimethyl-thiazol-2-yl-2,5-diphenyltetrazolium bromide] assay, exopolysaccharide staining, live/dead staining, scanning electron microscopy (SEM, and transverse microradiography (TMR were performed to study the anti-biofilm and anti-demineralization effects of the dental adhesives. The results showed that incorporating QAMs with different alkyl chain lengths into the adhesives had no obvious effect on the dentin bond strength. The adhesives containing QAMs with a longer alkyl chain developed healthier biofilms. The surface charge density, anti-biofilm, and anti-demineralization effects of the adhesives increased with a CL of the QAMs from 3 to 12, but decreased slightly with a CL from 12 to 16. In conclusion, adhesives containing QAMs with a tailored chain length are promising for preventing secondary caries in an “ecological way”.

  11. Prediction of Separation Length of Turbulent Multiphase Flow Using Radiotracer and Computational Fluid Dynamics Simulation

    International Nuclear Information System (INIS)

    Sugiharto, S.; Kurniadi, R.; Abidin, Z.; Stegowski, Z.; Furman, L.

    2013-01-01

    Multiphase flow modeling presents great challenges due to its extreme importance in various industrial and environmental applications. In the present study, prediction of separation length of multiphase flow is examined experimentally by injection of two kinds of iodine-based radiotracer solutions into a hydrocarbon transport pipeline (HCT) having an inner diameter of 24 in (60,96 m). The main components of fluids in the pipeline are water 95%, crude oil 3% and gas 2%. A radiotracing experiment was carried out at the segment of pipe which is located far from branch points with assumptions that stratified flows in such segment were achieved. Two radiation detectors located at 80 and 100 m from injection point were used to generate residence time distribution (RTD) curve resulting from injection of radiotracer solutions. Multiphase computational fluid dynamics (CFD) simulations using Eulerian-Eulerian control volume and commercial CFD package Fluent 6.2 were employed to simulate separation length of multiphase flow. The results of study shows that the flow velocity of water is higher than the flow rate of crude oil in water-dominated system despite the higher density of water than the density of the crude oil. The separation length in multiphase flow predicted by Fluent mixture model is approximately 20 m, measured from injection point. This result confirms that the placement of the first radiation detector at the distance 80 m from the injection point was correct. (author)

  12. The impact of precise robotic lesion length measurement on stent length selection: ramifications for stent savings.

    Science.gov (United States)

    Campbell, Paul T; Kruse, Kevin R; Kroll, Christopher R; Patterson, Janet Y; Esposito, Michele J

    2015-09-01

    Coronary stent deployment outcomes can be negatively impacted by inaccurate lesion measurement and inappropriate stent length selection (SLS). We compared visual estimate of these parameters to those provided by the CorPath 200® Robotic PCI System. Sixty consecutive patients who underwent coronary stent placement utilizing the CorPath System were evaluated. The treating physician assessed orthogonal images and provided visual estimates of lesion length and SLS. The robotic system was then used for the same measures. SLS was considered to be accurate when visual estimate and robotic measures were in agreement. Visual estimate SLSs were considered to be "short" or "long" if they were below or above the robotic-selected stents, respectively. Only 35% (21/60) of visually estimated lesions resulted in accurate SLS, whereas 33% (20/60) and 32% (19/60) of the visually estimated SLSs were long and short, respectively. In 5 cases (8.3%), 1 less stent was placed based on the robotic lesion measurement being shorter than the visual estimate. Visual estimate assessment of lesion length and SLS is highly variable with 65% of the cases being inaccurately measured when compared to objective measures obtained from the robotic system. The 32% of the cases where lesions were visually estimated to be short represents cases that often require the use of extra stents after the full lesion is not covered by 1 stent [longitudinal geographic miss (LGM)]. Further, these data showed that the use of the robotic system prevented the use of extra stents in 8.3% of the cases. Measurement of lesions with robotic PCI may reduce measurement errors, need for extra stents, and LGM. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Does day length affect winter bird distribution? Testing the role of an elusive variable.

    Science.gov (United States)

    Carrascal, Luis M; Santos, Tomás; Tellería, José L

    2012-01-01

    Differences in day length may act as a critical factor in bird biology by introducing time constraints in energy acquisition during winter. Thus, differences in day length might operate as a main determinant of bird abundance along latitudinal gradients. This work examines the influence of day length on the abundance of wintering crested tits (Lophophanes cristatus) in 26 localities of Spanish juniper (Juniperus thurifera) dwarf woodlands (average height of 5 m) located along a latitudinal gradient in the Spanish highlands, while controlling for the influence of food availability, minimum night temperature, habitat structure and landscape characteristics. Top regression models in the AIC framework explained 56% of variance in bird numbers. All models incorporated day length as the variable with the highest magnitude effect. Food availability also played an important role, although only the crop of ripe juniper fruits, but not arthropods, positively affected crested tit abundance. Differences in vegetation structure across localities had also a strong positive effect (average tree height and juniper tree density). Geographical variation in night temperature had no influence on crested tit distribution, despite the low winter temperatures reached in these dwarf forests. This paper demonstrates for the first time that winter bird abundance increases with day length after controlling for the effect of other environmental variables. Winter average difference in day length was only 10.5 minutes per day along the 1°47' latitudinal interval (190 km) included in this study. This amount of time, which reaches 13.5 h accumulated throughout the winter season, appears to be large enough to affect the long-term energy budget of small passerines during winter and to shape the distribution of winter bird abundance under restrictive environmental conditions.

  14. Does day length affect winter bird distribution? Testing the role of an elusive variable.

    Directory of Open Access Journals (Sweden)

    Luis M Carrascal

    Full Text Available Differences in day length may act as a critical factor in bird biology by introducing time constraints in energy acquisition during winter. Thus, differences in day length might operate as a main determinant of bird abundance along latitudinal gradients. This work examines the influence of day length on the abundance of wintering crested tits (Lophophanes cristatus in 26 localities of Spanish juniper (Juniperus thurifera dwarf woodlands (average height of 5 m located along a latitudinal gradient in the Spanish highlands, while controlling for the influence of food availability, minimum night temperature, habitat structure and landscape characteristics. Top regression models in the AIC framework explained 56% of variance in bird numbers. All models incorporated day length as the variable with the highest magnitude effect. Food availability also played an important role, although only the crop of ripe juniper fruits, but not arthropods, positively affected crested tit abundance. Differences in vegetation structure across localities had also a strong positive effect (average tree height and juniper tree density. Geographical variation in night temperature had no influence on crested tit distribution, despite the low winter temperatures reached in these dwarf forests. This paper demonstrates for the first time that winter bird abundance increases with day length after controlling for the effect of other environmental variables. Winter average difference in day length was only 10.5 minutes per day along the 1°47' latitudinal interval (190 km included in this study. This amount of time, which reaches 13.5 h accumulated throughout the winter season, appears to be large enough to affect the long-term energy budget of small passerines during winter and to shape the distribution of winter bird abundance under restrictive environmental conditions.

  15. Two-dimensional density and density fluctuation diagnostic for the edge plasma in fusion devices

    Science.gov (United States)

    Zoletnik, S.; Petravich, G.; Bencze, A.; Berta, M.; Fiedler, S.; McCormick, K.; Schweinzer, J.

    2005-07-01

    A technique is described for the two-dimensional measurement of electron density profile and fluctuations in edge regions of magnetically confined fusion plasmas. The method is based on existing lithium beam beam emission spectroscopy technique, two-dimensional resolution is achieved by electrostatically scanning the beam. If scanning is performed faster than the lifetime of the turbulent structures in the plasma, the diagnostic is capable of measuring the structure of electron density fluctuations as well. The beam strength of currently available beams makes the detection of single fluctuation events impossible, but the full two-dimensional spatial structure of correlations can still be determined. The article describes the technique and fast beam deflection tests up to 250kHz. The capabilities of such a diagnostic for fluctuation measurement are explored by simulating measurement signals. Measurement of both the two-dimensional density profile, fluctuation correlation function and poloidal flow velocity are demonstrated at the Wendelstein 7-AS stellarator. The shape of the density profile, the radial and poloidal correlation lengths and the flow velocity are in agreement with expectations and previous Langmuir probe measurement.

  16. Carbon nanotube growth density control

    Science.gov (United States)

    Delzeit, Lance D. (Inventor); Schipper, John F. (Inventor)

    2010-01-01

    Method and system for combined coarse scale control and fine scale control of growth density of a carbon nanotube (CNT) array on a substrate, using a selected electrical field adjacent to a substrate surface for coarse scale density control (by one or more orders of magnitude) and a selected CNT growth temperature range for fine scale density control (by multiplicative factors of less than an order of magnitude) of CNT growth density. Two spaced apart regions on a substrate may have different CNT growth densities and/or may use different feed gases for CNT growth.

  17. Fibre operating lengths of human lower limb muscles during walking.

    Science.gov (United States)

    Arnold, Edith M; Delp, Scott L

    2011-05-27

    Muscles actuate movement by generating forces. The forces generated by muscles are highly dependent on their fibre lengths, yet it is difficult to measure the lengths over which muscle fibres operate during movement. We combined experimental measurements of joint angles and muscle activation patterns during walking with a musculoskeletal model that captures the relationships between muscle fibre lengths, joint angles and muscle activations for muscles of the lower limb. We used this musculoskeletal model to produce a simulation of muscle-tendon dynamics during walking and calculated fibre operating lengths (i.e. the length of muscle fibres relative to their optimal fibre length) for 17 lower limb muscles. Our results indicate that when musculotendon compliance is low, the muscle fibre operating length is determined predominantly by the joint angles and muscle moment arms. If musculotendon compliance is high, muscle fibre operating length is more dependent on activation level and force-length-velocity effects. We found that muscles operate on multiple limbs of the force-length curve (i.e. ascending, plateau and descending limbs) during the gait cycle, but are active within a smaller portion of their total operating range.

  18. Correcting length-frequency distributions for imperfect detection

    Science.gov (United States)

    Breton, André R.; Hawkins, John A.; Winkelman, Dana L.

    2013-01-01

    Sampling gear selects for specific sizes of fish, which may bias length-frequency distributions that are commonly used to assess population size structure, recruitment patterns, growth, and survival. To properly correct for sampling biases caused by gear and other sources, length-frequency distributions need to be corrected for imperfect detection. We describe a method for adjusting length-frequency distributions when capture and recapture probabilities are a function of fish length, temporal variation, and capture history. The method is applied to a study involving the removal of Smallmouth Bass Micropterus dolomieu by boat electrofishing from a 38.6-km reach on the Yampa River, Colorado. Smallmouth Bass longer than 100 mm were marked and released alive from 2005 to 2010 on one or more electrofishing passes and removed on all other passes from the population. Using the Huggins mark–recapture model, we detected a significant effect of fish total length, previous capture history (behavior), year, pass, year×behavior, and year×pass on capture and recapture probabilities. We demonstrate how to partition the Huggins estimate of abundance into length frequencies to correct for these effects. Uncorrected length frequencies of fish removed from Little Yampa Canyon were negatively biased in every year by as much as 88% relative to mark–recapture estimates for the smallest length-class in our analysis (100–110 mm). Bias declined but remained high even for adult length-classes (≥200 mm). The pattern of bias across length-classes was variable across years. The percentage of unadjusted counts that were below the lower 95% confidence interval from our adjusted length-frequency estimates were 95, 89, 84, 78, 81, and 92% from 2005 to 2010, respectively. Length-frequency distributions are widely used in fisheries science and management. Our simple method for correcting length-frequency estimates for imperfect detection could be widely applied when mark–recapture data

  19. Non-universal and universal aspects of the large scattering length limit

    Science.gov (United States)

    Miller, Gerald A.

    2018-02-01

    The momentum density, n (k) of interacting many-body Fermionic systems is studied (for k >kF) using examples of several well-known two-body interaction models. It is shown that n (k) can be approximated by a zero-range model for momenta k less than about 0.1 /re, where re the effective range. If the scattering length is large and one includes the effects of a fixed value of re ≠ 0, n (k) is almost universal for momenta k up to about 2 /re. However, n (k) can not be approximated by a zero-range model for momenta k greater than about 1 / (a re2)1/3, where a is the scattering length, and if one wishes to maintain a sum rule that relates the energy of a two component Fermi-gas to an integral involving the density. We also show that the short separation distance, s, behavior of the pair density varies as s6.

  20. Penetration length-dependent hot electrons in the field emission from ZnO nanowires

    Science.gov (United States)

    Chen, Yicong; Song, Xiaomeng; Li, Zhibing; She, Juncong; Deng, Shaozhi; Xu, Ningsheng; Chen, Jun

    2018-01-01

    In the framework of field emission, whether or not hot electrons can form in the semiconductor emitters under a surface penetration field is of great concern, which will provide not only a comprehensive physical picture of field emission from semiconductor but also guidance on how to improve device performance. However, apart from some theoretical work, its experimental evidence has not been reported yet. In this article, the field penetration length-dependent hot electrons were observed in the field emission of ZnO nanowires through the in-situ study of its electrical and field emission characteristic before and after NH3 plasma treatment in an ultrahigh vacuum system. After the treatment, most of the nanowires have an increased carrier density but reduced field emission current. The raised carrier density was caused by the increased content of oxygen vacancies, while the degraded field emission current was attributed to the lower kinetic energy of hot electrons caused by the shorter penetration length. All of these results suggest that the field emission properties of ZnO nanowires can be optimized by modifying their carrier density to balance both the kinetic energy of field induced hot electrons and the limitation of saturated current under a given field.

  1. Scalp hair length. I. Hair length in Florida theme parks: an approximation of hair length in the United States of America.

    Science.gov (United States)

    Robbins, Clarence; Robbins, Marjorie Gene

    2003-01-01

    Ten hair length studies were conducted (January through May of 2001) at theme parks in central Florida, by observing and counting people with different lengths of hair with reference to specific anatomical sites. We observed 13.20% of the 24,300 males and females with hair shoulder-length or longer and 2.43% with hair down to the bottom of the shoulder blades or longer. We observed only 77 persons or 0.32% with hair waist-length or longer. Only three of these 77 persons were men. We observed 22 men with hair shoulder-length or longer or about 0.18%, among men only. Only four women, representing 0.0165% of this population, had hair reaching to the bottom of the buttocks. Hairstyles such as buns, topknots, or other styles of wearing hair bound to the head did interfere with our estimate of shorter lengths but not the longer ones (waist-length or longer). Head covers, e.g., caps, hats, scarves, etc., did not interfere with these estimates.

  2. Perception of the length of an object through dynamic touch is invariant across changes in the medium.

    Science.gov (United States)

    Mangalam, Madhur; Barton, Sophie A; Wagman, Jeffrey B; Fragaszy, Dorothy M; Newell, Karl M

    2017-11-01

    Rotational inertia-a mechanical quantity that describes the differential resistance of an object to angular acceleration in different directions-has been shown to support perception of the properties of that object through dynamic touch (wielding). The goal of the present study was to examine if perception of the length of an object through dynamic touch depends on its rotational inertia, independent of the medium in which it is wielded. The participants (n = 14) wielded 12 different objects held in air or completely immersed in water and reported perceived lengths of those objects. Each object consisted of a rod of a particular density with a particular number of stacked steel rings attached at a particular location along its length. Perceived length was invariant across medium. In addition, a single-valued function of the major eigenvalue, I 1 , and the minor eigenvalue, I 3 , of the rotational inertia, I, of the 12 objects predicted the perceived lengths of those objects in both air and water, and the perceived lengths were invariant across the two media. These results support the hypothesis that the informational support for perception of the length of an object through dynamic touch is invariant across changes in the medium.

  3. Modulation of Zn-C Bond Lengths Induced by Ligand Architecture in Zinc Carbatrane Compounds.

    Science.gov (United States)

    Ruccolo, Serge; Sattler, Wesley; Rong, Yi; Parkin, Gerard

    2016-11-09

    Bond lengths between pairs of atoms in covalent molecules are generally predicted well by the sum of their respective covalent radii, such that there are usually only small variations in related compounds. It is, therefore, significant that we have demonstrated that the incorporation of appropriately sized linkers between carbon and a metal center provides a means to modulate the length and nature of a metal-carbon interaction. Specifically, X-ray diffraction studies on a series of tris(1-methylimidazol-2-ylthio)methyl zinc complexes, [Titm Me ]ZnX, demonstrate how the Zn-C bond lengths are highly variable (2.17-2.68 Å) and are up to 0.67 Å longer than the average value listed in the Cambridge Structural Database (2.01 Å). Furthermore, density functional theory calculations on [Titm Me ]ZnCl demonstrate that the interaction is very flexible, such that either increasing or decreasing the Zn-C length from that in the equilibrium structure is associated with little energy change in comparison to that for other compounds with Zn-C bonds.

  4. Uranium fission track length distribution modelling for retracing chronothermometrical history of minerals

    International Nuclear Information System (INIS)

    Rebetez, M.

    1987-01-01

    Spontaneous fission of uranium 238 isotope contained in certain minerals creates damage zones called latent tracks, that can be etched chemically. The observation of these etched tracks and the measurement of their characteristics using an optical microscope are the basis of several applications in the domain of the earth sciences. First, the determination of their densities permits dating a mineral and establishing uranium mapping of rocks. Second, the measurement of their lengths can be a good source of information for retracing the thermal and tectonic history of the sample. The study of the partial annealing of tracks in apatite appears to be the ideal indicator for the evaluation of petroleum potential of a sedimentary basin. To allow the development of this application, it is necessary to devise a theoretical model of track length distributions. The model which is proposed takes into account the most realistic hypotheses concerning registration, etching and observation of tracks. The characteristics of surface tracks (projected lengths, depths, inclination angles, real lengths) and confined tracks (Track IN Track and Track IN Cleavage) are calculated. Surface tracks and confined tracks are perfectly complementary for chrono-thermometric interpretation of complex geological histories. The method is applied to the case of two samples with different tectonic history, issued from the cretaceous alcalin magmatism from the Pyrenees (Bilbao, Spain). A graphic method of distribution deconvolution is proposed. Finally, the uranium migration, depending on the hydrothermal alteration, is studied on the granite from Auriat (France) [fr

  5. Anomalous length dependence of conductance of aromatic nanoribbons with amine anchoring groups

    KAUST Repository

    Bilić, Ante

    2012-09-06

    Two sets of aromatic nanoribbons, based around a common hexagonal scaffolding, with single and dual terminal amine groups have been considered as potential molecular wires in a junction formed by gold leads. Charge transport through the two-terminal device has been modeled using density functional theory (with and without self-interaction correction) and the nonequilibrium Green\\'s function method. The effects of wire length, multiple terminal contacts, and pathways across the junction have been investigated. For nanoribbons with the oligopyrene motif and conventional single amine terminal groups, an increase in the wire length causes an exponential drop in the conductance. In contrast, for the nanoribbons with the oligoperylene motif and dual amine anchoring groups the predicted conductance rises with the wire length over the whole range of investigated lengths. Only when the effects of self-interaction correction are taken into account, the conductance of the oligoperylene ribbons exhibits saturation for longer members of the series. The oligoperylene nanoribbons, with dual amine groups at both terminals, show the potential to fully harness the highly conjugated system of π molecular orbitals across the junction. © 2012 American Physical Society.

  6. Extremal-point densities of interface fluctuations

    International Nuclear Information System (INIS)

    Toroczkai, Z.; Korniss, G.; Das Sarma, S.; Zia, R. K. P.

    2000-01-01

    We introduce and investigate the stochastic dynamics of the density of local extrema (minima and maxima) of nonequilibrium surface fluctuations. We give a number of analytic results for interface fluctuations described by linear Langevin equations, and for on-lattice, solid-on-solid surface-growth models. We show that, in spite of the nonuniversal character of the quantities studied, their behavior against the variation of the microscopic length scales can present generic features, characteristic of the macroscopic observables of the system. The quantities investigated here provide us with tools that give an unorthodox approach to the dynamics of surface morphologies: a statistical analysis from the short-wavelength end of the Fourier decomposition spectrum. In addition to surface-growth applications, our results can be used to solve the asymptotic scalability problem of massively parallel algorithms for discrete-event simulations, which are extensively used in Monte Carlo simulations on parallel architectures. (c) 2000 The American Physical Society

  7. The length of the glaciers in the world

    DEFF Research Database (Denmark)

    Machguth, Horst; Huss, M.; 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...

  8. 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......% CI: 9-48%) of total bag size. This overall effect interacted with the motivation for season length changes, being strongest for ‘other reasons’ (mainly harmonization of hunting periods for related species) but was absent when seasons were changed for reasons of ‘population management’. In sedentary......Manipulating hunting season length is often used as a population management tool but the effects of these changes on total harvest have rarely been studied. We modelled relative changes in national annual bag size as a function of relative change in hunting season length in 63 cases involving 28...

  9. Relation between Tolman length and isothermal compressibility for simple liquids

    International Nuclear Information System (INIS)

    Wang Xiao-Song; Zhu Ru-Zeng

    2013-01-01

    The Tolman length δ 0 of a liquid with a plane surface has attracted increasing theoretical attention in recent years, but the expression of Tolman length in terms of observable quantities is still not very clear. In 2001, Bartell gave a simple expression of Tolman length δ 0 in terms of isothermal compressibility. However, this expression predicts that Tolman length is always negative, which is contrary to the results of molecular dynamics simulations (MDS) for simple liquids. In this paper, this contradiction is analyzed and the reason for the discrepancy in the sign is found. In addition, we introduce a new expression of Tolman length in terms of isothermal compressibility for simple fluids not near the critical points under some weak restrictions. The Tolman length of simple liquids calculated by using this formula is consistent with that obtained using MDS regarding the sign

  10. Realization and field emission of CdSe nano-tetrapods with different arm lengths

    International Nuclear Information System (INIS)

    Zhao Lijuan; Pang Qi; Yang Shihe; Ge Weikun; Wang Jiannong

    2009-01-01

    The arms of CdSe nano-tetrapods can be greatly elongated with the core diameters and arm width unchanged by multiple injections. Room-temperature absorption and photoluminescence (PL) spectra of tetrapods with different arm lengths show that these tetrapods have almost the same core size, which is consistent with the high resolution TEM results. Field emission characteristics show that the onset field required drawing a current density of ∼0.1 μAcm -2 from CdSe nano-tetrapods with different arm lengths are 22 Vμm -1 , 9 Vμm -1 , and 4 Vμm -1 , respectively, and the field enhancement factors are determined to be about 218, 554, and 946, respectively. Results show that the longer is the arm of the tetrapods, the lower the turn-on field and the higher the field enhancement factor.

  11. On the use of the Prandtl mixing length model in the cutting torch modeling

    International Nuclear Information System (INIS)

    Mancinelli, B; Minotti, F O; Kelly, H

    2011-01-01

    The Prandtl mixing length model has been used to take into account the turbulent effects in a 30 A high-energy density cutting torch model. In particular, the model requires the introduction of only one adjustable coefficient c corresponding to the length of action of the turbulence. It is shown that the c value has little effect on the plasma temperature profiles outside the nozzle (the differences being less than 10 %), but severely affects the plasma velocity distribution, with differences reaching about 100% at the middle of the nozzle-anode gap. Within the experimental uncertainties it was also found that the value c = 0.08 allows to reproduce both, the experimental data of velocity and temperature

  12. The length-scale dependence of strain in networks by SANS

    CERN Document Server

    Pyckhout-Hintzen, W; Heinrich, M; Richter, D; Westermann, S; Straube, E

    2002-01-01

    We present a SANS study of the length-scale dependence of chain deformation by means of a suitable labeling in dense, cross-linked elastomers of the HDH-type. This length scale is controlled by the size of the label as well as the cross-link density. The results are compared to long homopolymers. The data are analyzed by means of the tube model of topology in rubber elasticity in combination with the random-phase approximation (RPA) to account for interchain correlations. Chain degradation during cross linking is treated by the standard RPA approach for polydisperse multicomponent systems. A transition from locally freely fluctuating to tube-constrained segmental motion was observed. (orig.)

  13. Assessment of fatigue crack length via plastic deformation in compact tension specimens using magnetic Barkhausen noise

    International Nuclear Information System (INIS)

    Reyes-Rodriguez, F. de los; Diego-Velasco, G. de; Capo-Sanchez, J.; Franco-Fidalgo, E.

    2013-01-01

    In this paper the influence of different parameters on crack length is determined via plastic deformation using magnetic Barkhausen noise; the compact specimens steel used in this study were 12Cr1MoV and 11Cr1Mo, which are used for steam transportation on power plants. The main objective of this paper is to determine the crack length and its incubation time using magnetic Barkhausen noise, which lets to improve the pre-cracking process prior creep crack growth rate test simulating the real conditions of high pressure and temperature of main steam lines. Results showed that mean root square and maximum pick of voltage decrease with plastic deformation for each steel analyzed in this work, on the other hand, with the increasing of plastic deformation, a logic relationship between plastic deformation and spectrum density is observed for mid frequencies values, as well as, a variation of the amplitude, width and shape of the Barkhausen signal envelope. (Author)

  14. Predicting length of stay in specialist neurological rehabilitation.

    Science.gov (United States)

    Taiwo, Whitney; Wressle, Alexandra; Bradley, Lloyd

    2018-03-01

    A retrospective case series was performed to determine which measures of complexity, dependency and function most accurately predict inpatient neurorehabilitation length of stay for individuals with post-acute neurological disorders. Sociodemographic, medical and functional variables were extracted from data submitted to the UK Rehabilitation Outcomes Collaborative. Length of stay was calculated as the total number of inpatient days, functional status was measured using Barthel Index, rehabilitation complexity was measured using Extended Rehabilitation Complexity Scale, and nursing dependency was measured using the Northwick Park Dependency Scale. The mean rehabilitation length of stay was 70.9 days, with length of stay being 35.1 days higher in inpatients with acquired brain injury than inpatients with spinal cord injury. Diagnostic category, Barthel Index scores, Extended Rehabilitation Complexity Scale scores and Northwick Park Dependency Scale scores at admission independently predicted length of stay. Multiple regressions including diagnostic group, Barthel Index, Extended Rehabilitation Complexity Scale and Northwick Park Dependency Scale statistically significantly predicted 37.9% of the variability in length of stay (p Scale on admission was most closely correlated with inpatient length of stay. In conclusion, inpatient length of stay is predicted by diagnostic category, Extended Rehabilitation Complexity Scale, Northwick Park Dependency Scale and Barthel Index. The most influential predictor of rehabilitation length of stay was Northwick Park Dependency Scale score at admission. These results may help facilitate rehabilitation resource planning and implementation of effective commissioning plans. Implications for Rehabilitation The most accurate predicting variable for length of stay in inpatient neurological rehabilitation was nursing need as measured by the Northwick Park Dependency Scale score on admission. Service users and commissioners can be

  15. Buckled graphene: A model study based on density functional theory

    KAUST Repository

    Khan, Yasser

    2010-09-01

    We make use of ab initio calculations within density functional theory to investigate the influence of buckling on the electronic structure of single layer graphene. Our systematic study addresses a wide range of bond length and bond angle variations in order to obtain insights into the energy scale associated with the formation of ripples in a graphene sheet. © 2010 Elsevier B.V. All rights reserved.

  16. Impact of neutral density fluctuations on gas puff imaging diagnostics

    Science.gov (United States)

    Wersal, C.; Ricci, P.

    2017-11-01

    A three-dimensional turbulence simulation of the SOL and edge regions of a toroidally limited tokamak is carried out. The simulation couples self-consistently the drift-reduced two-fluid Braginskii equations to a kinetic equation for neutral atoms. A diagnostic neutral gas puff on the low-field side midplane is included and the impact of neutral density fluctuations on D_α light emission investigated. We find that neutral density fluctuations affect the D_α emission. In particular, at a radial distance from the gas puff smaller than the neutral mean free path, neutral density fluctuations are anti-correlated with plasma density, electron temperature, and D_α fluctuations. It follows that the neutral fluctuations reduce the D_α emission in most of the observed region and, therefore, have to be taken into account when interpreting the amplitude of the D_α emission. On the other hand, higher order statistical moments (skewness, kurtosis) and turbulence characteristics (such as correlation length, or the autocorrelation time) are not significantly affected by the neutral fluctuations. At distances from the gas puff larger than the neutral mean free path, a non-local shadowing effect influences the neutral density fluctuations. There, the D_α fluctuations are correlated with the neutral density fluctuations, and the high-order statistical moments and measurements of other turbulence properties are strongly affected by the neutral density fluctuations.

  17. 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....

  18. Cervical length measurement: comparison of transabdominal and transvaginal approach

    DEFF Research Database (Denmark)

    Westerway, Sue C; Pedersen, Lars Henning; Hyett, Jon

    2015-01-01

    plots showed an inverse trend with shorter cervixes. In women with a cervix TV scan measurement, TA overestimated cervical length by 12 mm (P ... accurately, particularly if the cervix is short. At 24–34 weeks, a policy of proceeding to TV scan if TA measurement is women attending with symptoms and signs......Objective: To compare transabdominal (TA) and transvaginal (TV) ultrasound assessment of cervical length at 16-41 weeks gestation. Methods: TA and TV ultrasound measurements of cervical length were made on 491 pregnancies of 16-41 weeks gestation. Cervical length was measured from internal...

  19. Short Rayleigh length free electron laser: Experiments and simulations

    Directory of Open Access Journals (Sweden)

    P. P. Crooker

    2008-09-01

    Full Text Available We report experiments at Jefferson National Accelerator Facility (Jlab and computer simulations performed at the Naval Postgraduate School (NPS designed to probe the small Rayleigh length regime. We compare the gain, power, and sensitivity to mirror and electron beam misalignments as a function of decreasing Rayleigh length. The agreement is quite good, with experiments and simulations showing comparable trends as the Rayleigh length is decreased. In particular, we find that the gain and power do not decrease substantially at short Rayleigh length, contrary to a common Gaussian-mode filling factor argument. Within currently achievable alignment tolerances, the gain and power are still acceptable for FEL operation.

  20. Bunch length measurements in the SLC damping ring

    International Nuclear Information System (INIS)

    Decker, F.J.; Limberg, T.; Minty, M.; Ross, M.

    1993-05-01

    The synchrotron light of the SLC damping ring was used to measure the bunch length with a streak camera at different times in the damping cycle. There are bunch length oscillations after injection, different equilibrium length during the cycle due to rf manipulations to avoid microwave instability oscillations, and just before extraction there is a longitudinal phase space rotation (bunch muncher) to shorten the bunch length. Measurements under these different conditions are presented and compared with BPM pulse height signals. Calibration and adjustment issues and the connection of the streak camera to the SLC control system are also discussed

  1. Nuclear cycle length economics strategy using stochastic and deterministic Monte Carlo computation models

    Energy Technology Data Exchange (ETDEWEB)

    Wook Ahn, T.

    2014-07-01

    Nuclear power plants (NPP) have historically been a low cost base-load electricity source because of their high fuel density and operational reliability. In the United States, NPPs typically run 18- to 24-month cycles to limit outage times and maximize capacity factor. recently, however, increased volatility in energy and fuel prices, lower natural gas prices, higher material costs, and new sources are challenging the nuclear industry. This warrants a study in developing a more robust cycle length and fuel burnup strategy to make NPPs more competitive. (Author)

  2. Super liquid density target designs

    International Nuclear Information System (INIS)

    Pan, Y.L.; Bailey, D.S.

    1976-01-01

    The success of laser fusion depends on obtaining near isentropic compression of fuel to very high densities and igniting this fuel. To date, the results of laser fusion experiments have been based mainly on the exploding pusher implosion of fusion capsules consisting of thin glass microballoons (wall thickness of less than 1 micron) filled with low density DT gas (initial density of a few mg/cc). Maximum DT densities of a few tenths of g/cc and temperatures of a few keV have been achieved in these experiments. We will discuss the results of LASNEX target design calculations for targets which: (a) can compress fuel to much higher densities using the capabilities of existing Nd-glass systems at LLL; (b) allow experimental measurement of the peak fuel density achieved

  3. Interaction of bovine serum albumin and human blood plasma with PEO-tethered surfaces: Influence of PEO chain length, grafting density, and temperature : Influence of PEO chain length, grafting density, and temperature

    NARCIS (Netherlands)

    Norde, Willem; Gage, D.

    2004-01-01

    Solid surfaces are modified by grafting poly(ethylene oxide), PEO, to influence their interaction with indwelling particles, in particular molecules of bovine serum albumin and human plasma proteins. As a rule, the grafted PEO layers suppress protein adsorption. The suppression is most effective

  4. Diagnostic value of newborn foot length to predict gestational age

    Directory of Open Access Journals (Sweden)

    Mutia Farah Fawziah

    2017-08-01

    Full Text Available Background  Identification of gestational age, especially within 48 hours of birth, is crucial for newborns, as the earlier preterm status is detected, the earlier the child can receive optimal management. Newborn foot length is an anthropometric measurement which is easy to perform, inexpensive, and potentially efficient for predicting gestational age. Objective  To analyze the diagnostic value of newborn foot length in predicting gestational age. Methods  This diagnostic study was performed between October 2016 and February 2017 in the High Care Unit of Neonates at Dr. Moewardi General Hospital, Surakarta. A total of 152 newborns were consecutively selected and underwent right foot length measurements before 96 hours of age. The correlation between newborn foot length to classify as full term and gestational age was analyzed with Spearman’s correlation test because of non-normal data distribution. The cut-off point of newborn foot length was calculated by receiver operating characteristic (ROC curve and diagnostic values of newborn foot length were analyzed by 2 x 2 table with SPSS 21.0 software. Results There were no significant differences between male and female newborns in terms of gestational age, birth weight, choronological age, and newborn foot length (P>0.05. Newborn foot length and gestational age had a significant correlation (r=0.53; P=0.000. The optimal cut-off newborn foot length to predict full term status was 7.1 cm. Newborn foot length below 7.1 cm had sensitivity 75%, specificity 98%, positive predictive value 94.3%, negative predictive value 90.6%, positive likelihood ratio 40.5, negative likelihood ratio 0.25, and post-test probability 94.29%, to predict preterm status in newborns. Conclusion  Newborn foot length can be used to predict gestational age, especially for the purpose of differentiating between preterm and full term newborns.

  5. Heterogeneity of spine bone density

    Energy Technology Data Exchange (ETDEWEB)

    Laskey, M.A.; Crisp, A.J.; Compston, J.E.; Khaw, K.-T. (Addenbrooke' s Hospital, Cambridge (United Kingdom))

    1993-05-01

    This short communication investigates how accurate bone density measured in the lumbar spine (L1-L4 or L2-L4) reflects the bone density of vertebrae where many compression fractures occur (T12 and L1). The ability of two dual-energy X-ray absorptiometers (Lunar DPX and Hologic QDR-1000) to determine the bone density of T12 was also investigated. (Author).

  6. Correlation between minority carrier diffusion length and microstructure in a-Si:H thin films

    International Nuclear Information System (INIS)

    Conte, G.; Fameli, G.; Nobile, G.; Rubino, A.; Terzini, E.; Villani, F.

    1993-01-01

    The aim of this work is to investigate the opto-electronic properties of amorphous hydrogenated silicon (a-Si:H). The deposition temperature was used as a driving force to modify the morphology and bonded hydrogen distribution. The influence of the hydrogen microstructure on the carrier m-t products was examined. The m-t products, for both carriers, were evaluated from the diffusion length measurement, by using the Steady State Photocarrier Grating (SSPG) technique, and from the photoconductivity in the steady state condition (SSPC). The m-t products were correlated with the defect density and Fermi level position. The effects of the defect density on the Fermi level position were examined within the framework of a defect pool model in order to justify the consistency of the results

  7. Electron Cloud Cyclotron Resonances in the Presence of a Short-bunch-length Relativistic Beam

    International Nuclear Information System (INIS)

    Celata, Christine; Celata, C.M.; Furman, Miguel A.; Vay, J.-L.; Wu, Jennifer W.

    2008-01-01

    Computer simulations using the 2D code 'POSINST' were used to study the formation of the electron cloud in the wiggler section of the positron damping ring of the International Linear Collider. In order to simulate an x-y slice of the wiggler (i.e., a slice perpendicular to the beam velocity), each simulation assumed a constant vertical magnetic field. At values of the magnetic field where the cyclotron frequency was an integral multiple of the bunch frequency, and where the field strength was less than approximately 0.6 T, equilibrium average electron densities were up to three times the density found at other neighboring field values. Effects of this resonance between the bunch and cyclotron frequency are expected to be non-negligible when the beam bunch length is much less than the product of the electron cyclotron period and the beam

  8. Sighting optics including an optical element having a first focal length and a second focal length and methods for sighting

    Science.gov (United States)

    Crandall, David Lynn

    2011-08-16

    Sighting optics include a front sight and a rear sight positioned in a 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.

  9. Importing low-density ideas to high-density revitalisation

    DEFF Research Database (Denmark)

    Arnholtz, Jens; Ibsen, Christian Lyhne; Ibsen, Flemming

    2016-01-01

    Why did union officials from a high-union-density country like Denmark choose to import an organising strategy from low-density countries such as the US and the UK? Drawing on in-depth interviews with key union officials and internal documents, the authors of this article argue two key points. Fi...

  10. Reason for termination of breastfeeding and the length of breastfeeding

    DEFF Research Database (Denmark)

    Jakobsen, M S; Sodemann, Morten; Mølbak, Kare

    1996-01-01

    In third world countries the length of breastfeeding often has a major influence on child mortality, morbidity and nutritional status. When evaluating the impact of length of breastfeeding the reason why a mother terminates breastfeeding is usually not taken into consideration....

  11. Length-Weight Relationship and Condition Factor of Clarias ...

    African Journals Online (AJOL)

    Length – weight relationship of Clarias anguillaris (Fam: Claridae) in Kontagora Reservoir, Niger State, Nigeria, was studied from January, 2007 - December, 2007. The fish species was obtained using a fleet of graded gill nets comprising of nine multi filament gill nets mesh sizes. The parameters a and b of the Length ...

  12. Ultrasonographic assessment of renal length in 310 Turkish children ...

    African Journals Online (AJOL)

    Scanning was performed with a 3.5 MHz ultrasound probe in the supine position. The ultrasonographic appearance of the kidneys we measured was normal. The maximum length of each kidney was measured. The renal length was correlated with somatic parameters including age, body height and weight. Regression ...

  13. Bubble length affects bubble speed in a rough microfluidic channel

    Science.gov (United States)

    Zhang, Quan; Turitsyn, Konstantin; Witten, Tom

    2010-03-01

    We discuss the creeping motion of bubbles of different length in rough capillary tubes filled with carrier fluids. This extends the results of BrethertonfootnotetextF.P.Bretherton, 1961, J. Fluid Mech., 10, 166. for an infinite-length bubble at small capillary number Ca in a circular tube. We first derive the asymptotic corrections to the speed owing to finite length. This dependence on length is exponentially small, with a decay length much shorter than the tube radius R. Then we discuss the effect of azimuthal roughness of the tube on the bubble speed. Tube roughness leads to a carrier fluid flow in the azimuthal plane; this flow controls the relaxation of the bubble shape to its infinite length limit. For long-wavelength roughness, we find that the above decay length becomes much longer and even comparable to R. This implies a much-enhanced dependence of the bubble velocity on length. A shorter bubble should then catch up with a longer bubble ahead of it in the same channel. This mechanism may explain catch-up effects seen experimentally.footnotetextR.Ismagilov, private communication.

  14. Newton's Radii, Maupertuis' Arc Length, and Voltaire's Giant

    Science.gov (United States)

    Simoson, Andrew J.

    2011-01-01

    Given two arc length measurements along the perimeter of an ellipse--one taken near the long diameter, the other taken anywhere else--how do you find the lengths of major and minor axes? This was a problem of great interest from the time of Newton's "Principia" until the mid-eighteenth century when France launched twin geodesic…

  15. Species abundance, length weight relationships of selected fishes of ...

    African Journals Online (AJOL)

    Seasonal abundance and length-weight relationships of 25 species of fish inhabiting the fresh water ecosystem of Mu river, - Fiidi-Makurdi were estimated from 441 specimens caught with different kinds of gears (set basket ... The parameters (a and b) of length -weight relationship of the form (a* Lb= VV) were estimated.

  16. The impact of cultural distance on bilateral arm's length exports

    NARCIS (Netherlands)

    Slangen, A.H.L.; Beugelsdijk, S.; Hennart, J.-F.

    2011-01-01

    Prior studies have argued and regularly found that cultural distance is negatively related to bilateral export flows, which are the sum of arm’s length and intra-firm exports. However, these macro-level studies overlook the firm-level insights that arm’s length exports are a substitute for arm’s

  17. Length- weight relationships, condition factor (K) and relative ...

    African Journals Online (AJOL)

    Length-weight relationship and condition factors were estimated for Dentex congoensis and Dentex angolensis of the family sparidae trawled from Nigeria Coastal water in 2009. A total number of 534 specimens ranging from 7.2 – 3.0 cm in total length and 5.4 – 489.8 g in weight were analyzed. The lengthweight ...

  18. Length-Weight Relationships Of Fishes From Anambra River ...

    African Journals Online (AJOL)

    The distributions of b and In a were normal and the correlation between them was negative (r = -0.864) and highly significant. STR permits conversion of standard to total length of each population. Keywords: Length-weight relationships, fishes, Anambra river. Animal Research International Vol. 1 (1) 2004: pp. 1-6 ...

  19. Length-Weight Relationships and Food Preference of Two Coastal ...

    African Journals Online (AJOL)

    Length-weight measurements were taken from well-preserved fish specimens from which stomachs were extracted for the analysis of the food contents, using frequency of occurrence, numerical and gravimetric methods, as well as index of relative importance. The length-frequency analysis showed a size distribution with a ...

  20. The importance of stride length and stride frequency in middle ...

    African Journals Online (AJOL)

    ... also found that the better runners have faster stride frequencies and that provincial middle distance runners use lower stride frequencies than international middle distance runners. Key Words: Biomechanics, stride length, stride frequency, maximum oxygen consumption, leg length, middle distance runners, road runners.

  1. Length-Weight Relationship And Condition Factor Of The Elephant ...

    African Journals Online (AJOL)

    A total of 791 elephant fish, Mormyrus rume specimens of various sizes were sampled from River Ose, southwestern Ngera. Length-weight relationship and condition factor of the M rume specimens were studied. Their standard lengths ranged from 15.0 to 45.0 cm. Mean standard lengthfor males, females and combined sex ...

  2. The influence of presentation method on auditory length perception

    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...

  3. length-weight relationship of hepsetus odoe in lapai - agaie ...

    African Journals Online (AJOL)

    Ibrahim Usman

    biometric relationship so that data collected from the field can be transform into appropriate indices (Ecoutin et al., 2005). Length and weight are two useful parameters used especially in fisheries assessment. This relationship known as length-weight relationship (LWR), is commonly used in the analysis of fisheries data.

  4. Working Length Determination of Root Canal of Young Permanent ...

    African Journals Online (AJOL)

    Working length was measured by tactile method using digital radiography and electronic method using apex locator with no 15 K file. Actual working length was established by grinding of cementum and dentine from the root apex and was observed under stereomicroscope. Data was collected and statistical analysis was ...

  5. Validation of Navigation Ultrasound for Clavicular Length Measurement

    DEFF Research Database (Denmark)

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

    2017-01-01

    ultrasound, to deliver accurate measurements seems promising. To examine the reliability and validity of navigation ultrasound for length measurements of the clavicle, a study was performed using length measurements performed before forensic autopsies from 2012 to 2013. In total, 38 bodies with a median age...

  6. Leg length, sitting height and postmenopausal breast cancer risk

    DEFF Research Database (Denmark)

    Mellemkjær, L; Christensen, J; Frederiksen, K

    2012-01-01

    Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height.......Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height....

  7. Assessment of colorectal length using the electromagnetic capsule tracking system

    DEFF Research Database (Denmark)

    Mark, E B; Poulsen, J L; Haase, A M

    2017-01-01

    AIM: We aimed to determine colorectal length with the 3D-Transit system by describing a 'centerline' of capsule movement and compare it to known anatomy, as determined by magnetic resonance imaging (MRI). Further, we aimed to test the day-to-day variation of colorectal length assessed with the sy...

  8. 29 CFR 4.11 - Arm's length proceedings.

    Science.gov (United States)

    2010-07-01

    ... agreement must be reached “as a result of arm's-length negotiations.” This provision precludes arrangements... arm's-length negotiations may be made through investigation, hearing or otherwise pursuant to the... employees, and interested Governmental agencies. Such a request shall be submitted in writing to the...

  9. Heritability of sperm length in the bumblebee Bombus terrestris

    DEFF Research Database (Denmark)

    Baer, Boris; de Jong, Gerdien; Schmid-Hempel, Regula

    2006-01-01

    Sperm length is highly variable, both between and within species, but the evolutionary significance of this variation is poorly understood. Sexual selection on sperm length requires a significant additive genetic variance, but few studies have actually measured this. Here we present the first est...

  10. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    Jane

    2011-07-18

    Jul 18, 2011 ... The purpose of this study was to clinically compare working length (WL) determination with root ZX apex locator and radiography, and then compare them with direct visualization method ex vivo. A total of 75 maxillary central and lateral incisors were selected. Working length determination was carried out.

  11. A multiset hook length formula and some applications

    OpenAIRE

    Dehaye, Paul-Olivier; Han, Guo-Niu

    2011-01-01

    A multiset hook length formula for integer partitions is established by using combinatorial manipulation. As special cases, we rederive three hook length formulas, two of them obtained by Nekrasov-Okounkov, the third one by Iqbal, Nazir, Raza and Saleem, who have made use of the cyclic symmetry of the topological vertex. A multiset hook-content formula is also proved.

  12. Accuracy of working length determination with root ZX apex locator ...

    African Journals Online (AJOL)

    The purpose of this study was to clinically compare working length (WL) determination with root ZX apex locator and radiography, and then compare them with direct visualization method ex vivo. A total of 75 maxillary central and lateral incisors were selected. Working length determination was carried out using radiographic ...

  13. Length-Weight Relationship and Fecundity of Clarias Gariepinus in ...

    African Journals Online (AJOL)

    Length-Weight Relationship and Fecundity of Clarias Gariepinus in a Tropical Reservoir, Southwest, Nigeria. ... International Journal of Tropical Agriculture and Food Systems ... The linear relationship of length and weight of the C. gariepinus population showed isometric growth pattern with 'b' values being higher than 3.

  14. Resonance and Neck Length for a Spherical Resonator

    Directory of Open Access Journals (Sweden)

    Emily Corning

    2011-06-01

    Full Text Available The relationship between the neck length of a spherical resonator and its period of fundamental resonance was investigated. This was done by measuring the frequency of fundamental resonance of the resonator at 6 different neck lengths. It was found that its resonance resembled Helmholtz resonance but was not that of ideal Helmholtz resonance.

  15. 42 CFR 402.205 - Length of exclusion.

    Science.gov (United States)

    2010-10-01

    ... maximum time limit for the period of exclusion. Social Security Actparagraph Code of Federal... 42 Public Health 2 2010-10-01 2010-10-01 false Length of exclusion. 402.205 Section 402.205 Public... PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS Exclusions § 402.205 Length of exclusion. The...

  16. Can physique and gluteal size predict penile length in adult ...

    African Journals Online (AJOL)

    Study design: A prospective study to test the scientific veracity of this traditional and apparently mythical belief. ... Conclusion: The supposed relationship between penile length and gluteal size may have a scientific basis, but contrary to belief, large buttocks is more predictive of longer penile length than small buttocks.

  17. Length-weight relationship and condition factor of clarias gariepinus ...

    African Journals Online (AJOL)

    Length-Weight relationship and condition factor of Clarias gariepinus and Tilapia Zillii were studiedin lake Alau and Monguno hatchery, both in Borno State of Nigeria, for a period of two weeks. A total of 98 C. gariepinus and 140. T. zillii were measured. The length-weight regression coefficient (b) for both fishes in lake Alau ...

  18. Length-weight relationships, condition factors and relative weight of ...

    African Journals Online (AJOL)

    The aim of this study was to record the length-weight relationship parameters and condition factors for some commercially important fish of Bushehr coastal waters of Persian Gulf. The length-weight relationships were calculated for five species caught during fishing surveys using different types of fishing gears (trawls, pots ...

  19. Correlation between Umbilical Cord Length, Birth Weight and ...

    African Journals Online (AJOL)

    Background: The umbilical cord and placenta have been considered to significantly contribute to the perinatal outcome. However, in our environment attempt at exploring its use has been limited due to sociocultural believes. This study aimed to identify the relationship between the umbilical cord length, newborn length and ...

  20. Length-weight relationship and condition factor of Macrobrachium ...

    African Journals Online (AJOL)

    Length-weight relationship and condition factor of 24 months samples of Macrobrachium vollenhovenii Herklots, 1857, from the Lagos – Lekki lagoon system were estimated. The parameters a and b of the length-weight relationship were -4.72 and 2.92 for male while the corresponding female values were -4.98 and 3.01.

  1. Length Frequency Distribution And Sex Ratio Of Macrobrachium ...

    African Journals Online (AJOL)

    Length frequency distribution and sex ratio of Macrobrachium macrobrachion sampled by cane traps in the Lagos –Lekki lagoon system were estimated from May 2002 to April 2004. The total number of size classes for the first and second year for both male and female ranged from 10 – 12. The length range was 3 to 14cm ...

  2. Cervical length assessment in women with idiopathic polyhydramnios.

    Science.gov (United States)

    Hershkovitz, R; Sheiner, E; Maymon, E; Erez, O; Mazor, M

    2006-11-01

    The aims of the study were to determine cervical length among patients with polyhydramnios and to assess the relationship between the severity of polyhydramnios, cervical length and gestational age at delivery. A prospective study was designed including 92 consecutive singleton pregnancies with polyhydramnios between 24 and 40 weeks' gestation. Cervical length was measured using transvaginal sonography. Polyhydramnios was defined when amniotic fluid index (AFI) was equal to or greater than 20 cm. A single sonologist performed all the examinations of the cervical length and the AFI. The median cervical length and AFI were 37.5 (range, 7-52) mm and 28.8 (range, 20-43) cm, respectively. A significant gradual shortening of the cervical length was observed with advancing gestational age (P=0.027). No significant association was found between AFI and cervical length (P=0.24). A cut-off of 15 mm (n=5) was associated with a significantly lower gestational age at delivery (30+/-2.6 weeks vs. 37.2+/-4.2 weeks, respectively, Ppolyhydramnios have a gradual shortening of cervical length with advancing gestational age. However, this finding is not related to the severity of polyhydramnios. Copyright (c) 2006 ISUOG.

  3. Cholecystectomy During the Weekend Increases Patients' Length of Hospital Stay

    DEFF Research Database (Denmark)

    Rothman, Josephine Philip; Burcharth, Jakob; Pommergaard, Hans-Christian

    2016-01-01

    30 days between week time and weekend time. A longer postoperative length of stay was observed for patients operated on Fridays and Saturdays even though surgical complication rates were alike between weekdays. Patients with acute cholecystitis had a longer length of stay on Saturdays. CONCLUSION: We...

  4. Climate reconstructions derived from global glacier length records

    NARCIS (Netherlands)

    Klok, E.J.; Oerlemans, J.

    2004-01-01

    As glacier length fluctuations provide useful information about past climate, we derived historic fluctuations in the equilibrium-line altitude (ELA) on the basis of 19 glacier length records from different parts of the world. We used a model that takes into account the geometry of the glacier,

  5. 5 CFR 838.441 - Computing lengths of service.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Computing lengths of service. 838.441... Affecting Refunds of Employee Contributions Procedures for Computing the Amount Payable § 838.441 Computing lengths of service. (a) The smallest unit of time that OPM will calculate in computing a formula in a...

  6. 5 CFR 838.242 - Computing lengths of service.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Computing lengths of service. 838.242... Affecting Employee Annuities Procedures for Computing the Amount Payable § 838.242 Computing lengths of service. (a)(1) The smallest unit of time that OPM will calculate in computing a formula in a court order...

  7. 5 CFR 838.623 - Computing lengths of service.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Computing lengths of service. 838.623 Section 838.623 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE... Employee Annuities or Refunds of Employee Contributions Computation of Benefits § 838.623 Computing lengths...

  8. Mammography density estimation with automated volumetic breast density measurement

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Su Yeon; Kim, Eun Kyung; Kim, Min Jung; Moon, Hee Jung [Dept. of Radiology, Severance Hospital, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2014-06-15

    To compare automated volumetric breast density measurement (VBDM) with radiologists' evaluations based on the Breast Imaging Reporting and Data System (BI-RADS), and to identify the factors associated with technical failure of VBDM. In this study, 1129 women aged 19-82 years who underwent mammography from December 2011 to January 2012 were included. Breast density evaluations by radiologists based on BI-RADS and by VBDM (Volpara Version 1.5.1) were compared. The agreement in interpreting breast density between radiologists and VBDM was determined based on four density grades (D1, D2, D3, and D4) and a binary classification of fatty (D1-2) vs. dense (D3-4) breast using kappa statistics. The association between technical failure of VBDM and patient age, total breast volume, fibroglandular tissue volume, history of partial mastectomy, the frequency of mass > 3 cm, and breast density was analyzed. The agreement between breast density evaluations by radiologists and VBDM was fair (k value = 0.26) when the four density grades (D1/D2/D3/D4) were used and moderate (k value = 0.47) for the binary classification (D1-2/D3-4). Twenty-seven women (2.4%) showed failure of VBDM. Small total breast volume, history of partial mastectomy, and high breast density were significantly associated with technical failure of VBDM (p 0.001 to 0.015). There is fair or moderate agreement in breast density evaluation between radiologists and VBDM. Technical failure of VBDM may be related to small total breast volume, a history of partial mastectomy, and high breast density.

  9. 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....

  10. Lesion length assessment using a new vessel caliper.

    Science.gov (United States)

    Wolyn, Robert; Dixon, Simon R; Almany, Steven L; Korotko, Joe; Huang, Raywin R; O'Neill, William W

    2003-02-01

    Assessment of coronary lesion length using visual estimation or quantitative coronary angiography can be unreliable. We tested the accuracy of a new handheld caliper device to measure lesion length in a bench-top model and in eight patients undergoing percutaneous coronary intervention (PCI). Caliper-derived length measurements were compared to the known reference distance in the bench-top model and visual or intravascular ultrasound (IVUS)-derived measurements in vivo. In the coronary model, caliper-derived measurements were accurate and correlated well with known reference distances regardless of the angiographic projection. During PCI, there was a poor correlation between the best visual estimate of length and IVUS-derived measurements. In contrast, caliper-derived measurements correlated closely with IVUS-derived measurements. This handheld caliper provides a simple and accurate method of assessing intracoronary lesion length and may be particularly useful during coronary stenting and when adjunctive brachytherapy is performed. Copyright 2003 Wiley-Liss, Inc.

  11. Real-time single-shot electron bunch length measurements

    CERN Document Server

    Wilke, I; Gillespie, W A; Berden, G; Knippels, G M H; Meer, A F G

    2002-01-01

    Linear accelerators employed as drivers for X-ray free electron lasers (FELs) require relativistic electron bunch with sub-picosecond bunch length. Precise bunch length measurements are important for the tuning and operation of the FELs. Previously, we have demonstrated that electro-optic detection is a powerful technique for sub-picosecond electron bunch length measurements. In those experiments, the measured bunch length was the average of all electron bunches within a macropulse. Here, for the first time, we present the measurement of the length of individual electron bunches using a development of our previous technique. In this experiment, the longitudinal electron bunch shape is encoded electro-optically on to the frequency spectrum of a chirped laser pulse. Subsequently, the laser pulse is dispersed by a grating and the spectrum is imaged with a CCD camera. Single bunch measurements are achieved by using a nanosecond gated camera, and synchronizing the gate with both the electron bunch and the laser pu...

  12. Sperm length evolution in the fungus-growing ants

    DEFF Research Database (Denmark)

    Baer, B.; Dijkstra, M. B.; Mueller, U. G.

    2009-01-01

    Eusocial insects offer special opportunities for the comparative study of sperm traits because sperm competition is absent (in species with obligatory monandry) or constrained (in lineages where queens mate multiply but never remate later in life). We measured sperm length in 19 species of fungus......-growing ants, representing 9 of the 12 recognized genera, and mapped these onto the ant phylogeny. We show that average sperm length across species is highly variable and decreases with mature colony size in basal genera with singly mated queens, suggesting that sperm production or storage constraints affect...... 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...

  13. Relative gut lengths of coral reef butterflyfishes (Pisces: Chaetodontidae)

    KAUST Repository

    Berumen, Michael L.

    2011-06-17

    Variation in gut length of closely related animals is known to generally be a good predictor of dietary habits. We examined gut length in 28 species of butterflyfishes (Chaetodontidae), which encompass a wide range of dietary types (planktivores, omnivores, and corallivores). We found general dietary patterns to be a good predictor of relative gut length, although we found high variation among groups and covariance with body size. The longest gut lengths are found in species that exclusively feed on the living tissue of corals, while the shortest gut length is found in a planktivorous species. Although we tried to control for phylogeny, corallivory has arisen multiple times in this family, confounding our analyses. The butterflyfishes, a speciose family with a wide range of dietary habits, may nonetheless provide an ideal system for future work studying gut physiology associated with specialization and foraging behaviors. © 2011 Springer-Verlag.

  14. Metal-insulator transition: the Mott criterion and coherence length

    CERN Document Server

    Pergament, A

    2003-01-01

    On the basis of the Mott criterion for metal-insulator transition (MIT), an expression for the correlation length, identical to that for the coherence length in the theory of superconductivity, is obtained. This correlation length characterizes the size of an electron-hole pair (in an excitonic insulator) or the effective Bohr radius (as, e.g., in doped semiconductors). The relation obtained is used for calculation of the coherence length in vanadium dioxide. The presence of two characteristic coherence lengths (xi sub 1 approx 20 A and xi sub 2 approx 2 A) is found. This is associated with the specific features of the transition mechanism in VO sub 2 : this mechanism represents a combination of the purely electronic Mott-Hubbard contribution and the structural (Peierls-like) one. It is shown, however, that the driving force of the MIT in VO sub 2 is the electron-correlation Mott-Hubbard transition.

  15. Birth Weight and Length as Predictors for Adult Height

    DEFF Research Database (Denmark)

    Sørensen, Henrik Toft; Sabroe, Svend; Rothman, Kenneth J.

    1999-01-01

    Adult height has been found to be inversely associated with mortality. Recently, it has been suggested that growth in utero is linked with adult risk of several chronic diseases. The authors examined possible associations between birth weight, birth length, and adult height in young Danish men...... birth weight and adult height; for subjects with birth weight or = 4,501 g, mean height was 184.1 cm. A positive association was also found between birth length and adult height. For subjects with birth length ... adult height was 175.2 cm, increasing to 184.3 cm at birth length > 56 cm. The associations between birth length and adult height persisted after adjustment for birth weight, gestational age, and other confounders, while the associations between birth weight and adult height almost disappeared when...

  16. Role of TERRA in the regulation of telomere length.

    Science.gov (United States)

    Wang, Caiqin; Zhao, Li; Lu, Shiming

    2015-01-01

    Telomere dysfunction is closely associated with human diseases such as cancer and ageing. Inappropriate changes in telomere length and/or structure result in telomere dysfunction. Telomeres have been considered to be transcriptionally silent, but it was recently demonstrated that mammalian telomeres are transcribed into telomeric repeat-containing RNA (TERRA). TERRA, a long non-coding RNA, participates in the regulation of telomere length, telomerase activity and heterochromatinization. The correct regulation of telomere length may be crucial to telomeric homeostasis and functions. Here, we summarize recent advances in our understanding of the crucial role of TERRA in the maintenance of telomere length, with focus on the variety of mechanisms by which TERRA is involved in the regulation of telomere length. This review aims to enable further understanding of how TERRA-targeted drugs can target telomere-related diseases.

  17. Time step length versus efficiency of Monte Carlo burnup calculations

    International Nuclear Information System (INIS)

    Dufek, Jan; Valtavirta, Ville

    2014-01-01

    Highlights: • Time step length largely affects efficiency of MC burnup calculations. • Efficiency of MC burnup calculations improves with decreasing time step length. • Results were obtained from SIE-based Monte Carlo burnup calculations. - Abstract: We demonstrate that efficiency of Monte Carlo burnup calculations can be largely affected by the selected time step length. This study employs the stochastic implicit Euler based coupling scheme for Monte Carlo burnup calculations that performs a number of inner iteration steps within each time step. In a series of calculations, we vary the time step length and the number of inner iteration steps; the results suggest that Monte Carlo burnup calculations get more efficient as the time step length is reduced. More time steps must be simulated as they get shorter; however, this is more than compensated by the decrease in computing cost per time step needed for achieving a certain accuracy

  18. Bedform Stability Fields for Smaller Density Ratio

    Science.gov (United States)

    Yokokawa, M.; Muraoka, S.; Murokawa, T.; Mizokami, Y.; Tsuji, A.; Kishimoto, K.; Naruse, H.

    2008-12-01

    When the fluid flow moves on the granular materials, the bed geometry, i.e., bedforms, change corresponding the flow conditions. Bedforms are the important source of information. From geological point of view, the bedforms migrate to generate the variety of sedimentary structures which can be used to reconstruct the paleo-hydraulic conditions. From the engineering point of view, bedforms have to be considered when the sediment transport and/or the bed roughness are discussed. Although there have been done numerous flume experiments both in the geology and engineering, most of the diagrams of bedform stability fields have been made using the silica materials and water, whose density ratio is about 2.65. Here we performed flume experiments for smaller density ratio, 1.5. This is aimed at examining the effect of density ratio on the bedform stability fields. Different density ratio can occur in the natural environments, such as under the hyperconcentrated flow, or on the surfaces of other planets. We performed flume experiments using the fragments of melamine resin, whose specific gravity is 1.5, and we used five kinds of size distributions. Small recirculating-flumes, 4 m in length, 0.3 or 0.4 m in depth and 0.08 m in width, in Kyoto University and Osaka Institute of Technology are used. The flume floor was laid with the material, and unidirectional flow was operated. The flow discharge was increased gradually, and bedform formation was observed. Flow discharge, flow depth, water-surface slope, and water temperature were measured. Based on these data, non-dimensional parameters, such as Mobility parameter, Particle parameter, and Froude number, were calculated and compared with those of quartz grains (Van den Berg and Van Gelder, 1993). As a result, we got bedform stability fields for the density ratio 1.5. Comparing with that of quartz grains, the following features were found. (1) The kinds of bedforms observed in these experiments were the same with those of

  19. 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.

  20. Length of urethra in the Indian adult male population

    Directory of Open Access Journals (Sweden)

    Venkatesh Krishnamoorthy

    2012-01-01

    Full Text Available Objective: The urethral length has not been measured in the Indian population. Even the international literature in this arena is very sparse. This paper is an attempt to develop a simple anatomical database for urethral length. Materials and Methods: Between January 2010 and April 2011, the urethral lengths of 422 adult male patients who required catheterization as part of regular treatment at our hospital, were recorded after obtaining consent from the patients and from the scientific and ethics review boards of the institution. Patients with history of prostatic or urethral abnormalities were excluded. The balloon of a sterile Foley′s catheter was inflated using 10 cc of saline. The length from the junction of the balloon to the ′Y′ junction of the Foley was measured. The catheter was then passed into the bladder and re-inflated to same volume. The penis was gently straightened and the length of the catheter outside the penis was measured till the premarked point at the ′Y′ junction. Subtracting this from the original length gave the length of the urethra. Results: The mean length of the urethra was 17.55 + 1.42 cm with a range between 14 and 22.5 cm. Conclusions: Literature in which the length of the normal adult male urethra is recorded for a significant sample size is very scarce. Our data adds to basic anatomic information of the male urethra specific to the Indian population. Statistical Methods: Descriptive statistical analysis was performed. The non-linear regression analysis was employed to find the normative values of urethral length according to age class.

  1. Thermodynamics of the Schwarzschild-AdS Black Hole with a Minimal Length

    Directory of Open Access Journals (Sweden)

    Yan-Gang Miao

    2017-01-01

    Full Text Available Using the mass-smeared scheme of black holes, we study the thermodynamics of black holes. Two interesting models are considered. One is the self-regular Schwarzschild-AdS black hole whose mass density is given by the analogue to probability densities of quantum hydrogen atoms. The other model is the same black hole but whose mass density is chosen to be a rational fractional function of radial coordinates. Both mass densities are in fact analytic expressions of the δ-function. We analyze the phase structures of the two models by investigating the heat capacity at constant pressure and the Gibbs free energy in an isothermal-isobaric ensemble. Both models fail to decay into the pure thermal radiation even with the positive Gibbs free energy due to the existence of a minimal length. Furthermore, we extend our analysis to a general mass-smeared form that is also associated with the δ-function and indicate the similar thermodynamic properties for various possible mass-smeared forms based on the δ-function.

  2. Abundance, stock origin, and length of marked and unmarked juvenile Chinook salmon in the surface waters of greater Puget Sound

    Science.gov (United States)

    Rice, C.A.; Greene, C.M.; Moran, P.; Teel, D.J.; Kuligowski, D.R.; Reisenbichler, R.R.; Beamer, E.M.; Karr, J.R.; Fresh, K.L.

    2011-01-01

    This study focuses on the use by juvenile Chinook salmon Oncorhynchus tshawytscha of the rarely studied neritic environment (surface waters overlaying the sublittoral zone) in greater Puget Sound. Juvenile Chinook salmon inhabit the sound from their late estuarine residence and early marine transition to their first year at sea. We measured the density, origin, and size of marked (known hatchery) and unmarked (majority naturally spawned) juveniles by means of monthly surface trawls at six river mouth estuaries in Puget Sound and the areas in between. Juvenile Chinook salmon were present in all months sampled (April-November). Unmarked fish in the northern portion of the study area showed broader seasonal distributions of density than did either marked fish in all areas or unmarked fish in the central and southern portions of the sound. Despite these temporal differences, the densities of marked fish appeared to drive most of the total density estimates across space and time. Genetic analysis and coded wire tag data provided us with documented individuals from at least 16 source populations and indicated that movement patterns and apparent residence time were, in part, a function of natal location and time passed since the release of these fish from hatcheries. Unmarked fish tended to be smaller than marked fish and had broader length frequency distributions. The lengths of unmarked fish were negatively related to the density of both marked and unmarked Chinook salmon, but those of marked fish were not. These results indicate more extensive use of estuarine environments by wild than by hatchery juvenile Chinook salmon as well as differential use (e.g., rearing and migration) of various geographic regions of greater Puget Sound by juvenile Chinook salmon in general. In addition, the results for hatchery-generated timing, density, and length differences have implications for the biological interactions between hatchery and wild fish throughout Puget Sound. ?? American

  3. Density and length in the neighborhood: Explaining cross-linguistic differences in learning to read in English and Dutch

    NARCIS (Netherlands)

    Marinus, E.; Nation, K.; de Jong, P.F.

    2015-01-01

    Two experiments examined underlying cognitive processes that may explain why it is harder to learn to read in English than in more transparent orthographies such as German and Dutch. Participants were English and Dutch readers from Grades 3 and 4. Experiment 1 probed the transition from serial to

  4. Proton conducting graft copolymers with tunable length and density of phosphonated side chains for fuel cell membranes

    DEFF Research Database (Denmark)

    Dimitrov, Ivaylo; Takamuku, Shogo; Jankova Atanasova, Katja

    2014-01-01

    gravimetrical analyses. The proton conductivity of membrane prepared from the graft copolymer with the shortest phosphonated side chains was 134 mS cm(-1) at 100 degrees C under fully immersed conditions. The graft copolymer TEM image shows a nanophase separation of ion-rich segments within the polysulfone...

  5. SYNTHESIS, CHARACTERIZATION AND DENSITY FUNCTIONAL ...

    African Journals Online (AJOL)

    Preferred Customer

    KEY WORDS: Monoacyl aniline, Synthesis, Density functional theory, Rotation barrier. INTRODUCTION ... on the electron density in the phenyl ring and the respective accelerating and decelerating effects on the rate of ... compounds were determined using Nujol mulls and of liquids either in dichloromethane or chloroform ...

  6. The Density of Sustainable Settlements

    DEFF Research Database (Denmark)

    Lauring, Michael; Silva, Victor; Jensen, Ole B.

    2010-01-01

    This paper is the initial result of a cross-disciplinary attempt to encircle an answer to the question of optimal densities of sustainable settlements. Urban density is an important component in the framework of sustainable development and influences not only the character and design of cities...

  7. density-dependent selection revisited

    Indian Academy of Sciences (India)

    Unknown

    phila under density-dependent selection. In a Drosophila culture with very high larval density the environment deteriorates in two ways over time: food tends to run out, and toxic nitrogenous metabolic wastes tend to accumulate. There is, thus, selection favouring the ability to develop fast under crowded conditions, and also ...

  8. Interferometric characterization of density dynamics of an ultradense Z-pinch plasma

    International Nuclear Information System (INIS)

    Ackenhusen, J.G.; Bach, D.R.

    1979-01-01

    We have measured the spatially and temporally resolved density in a Z-pinch plasma by holographic interferometry. The high electron density (4 x 10 19 e/cm 3 ), short density scale length (100 μm), and low temperature (about 20 eV) make the plasma source suitable for simulation of laser-pellet interaction experiments at 10.6-μm laser wavelengths. A cinema of density evolution, indicating plasma pinching and subsequent relaxation, provides an experimental view of plasma dynamics which is then compared to simple theoretical models

  9. Edge density profiles in high-performance JET plasmas

    International Nuclear Information System (INIS)

    Summers, D.D.R.; Viaccoz, B.; Vince, J.

    1997-01-01

    Detailed electron density profiles of the scrape-off layer in high-performance JET plasmas (plasma current, I p nbi ∝17 MW) have been measured by means of a lithium beam diagnostic system featuring high spatial resolution [Kadota (1978)[. Measurements were taken over a period of several seconds, allowing examination of the evolution of the edge profile at a location upstream from the divertor target. The data clearly show the effects of the H-mode transition - an increase in density near the plasma separatrix and a reduction in density scrape-off length. The profiles obtained under various plasma conditions are compared firstly with data from other diagnostics, located elsewhere in the vessel, and also with the predictions of an 'onion-skin' model (DIVIMP), which used, as initial parameters, data from an array of probes located in the divertor target. (orig.)

  10. Level density of 57Co

    International Nuclear Information System (INIS)

    Mishra, V.; Boukharouba, N.; Brient, C.E.; Grimes, S.M.; Pedroni, R.S.

    1994-01-01

    Levels in 57 Co have been studied in the region of resolved levels (E 57 Fe(p,n) 57 Co neutron spectrum with resolution ΔE∼5 keV. Seventeen previously unknown levels are located. Level density parameters in the continuum region are deduced from thick target measurements of the same reaction and additional level density information is deduced from Ericson fluctuation studies of the reaction 56 Fe(p,n) 56 Co. A set of level density parameters is found which describes the level density of 57 Co at energies up to 14 MeV. Efforts to obtain level density information from the 56 Fe(d,n) 57 Co reaction were unsuccessful, but estimates of the fraction of the deuteron absorption cross section corresponding to compound nucleus formation are obtained

  11. Empirical model description of photon path length for differential path length spectroscopy: combined effect of scattering and absorption

    NARCIS (Netherlands)

    Kanick, Stephen C.; Sterenborg, Henricus J. C. M.; Amelink, Arjen

    2008-01-01

    Differential path length spectroscopy (DPS) is a method of reflectance spectroscopy that utilizes a specialized fiber geometry to make the photon path length (tau) insensitive to variations in tissue optical properties over a wide range of absorption (mu(a)) and total scattering (mu(s))

  12. Validity of plant fiber length measurement : a review of fiber length measurement based on kenaf as a model

    Science.gov (United States)

    James S. Han; Theodore. Mianowski; Yi-yu. Lin

    1999-01-01

    The efficacy of fiber length measurement techniques such as digitizing, the Kajaani procedure, and NIH Image are compared in order to determine the optimal tool. Kenaf bast fibers, aspen, and red pine fibers were collected from different anatomical parts, and the fiber lengths were compared using various analytical tools. A statistical analysis on the validity of the...

  13. [Effects of fertilization on fine root diameter, root length and specific root length in Larix kaempferi plantation].

    Science.gov (United States)

    Yu, Li-zhong; Ding, Guo-quan; Shi, Jian-wei; Yu, Shui-qiang; Zhu, Jiao-jun; Zhao, Lian-fu

    2007-05-01

    With 16 years old Larix kaempfersoil plantation in the mountainous area of eastern Liaoning Province as test object, this paper studied the effects of fertilization on the fine root diameter, root length, and specific root length (SRL) of the first to fifth order roots. The results showed that with ascending root orders, the mean fine root diameter and root length increased, while the SRL decreased significantly. Among the five order roots, the first order roots were the thinnest in diameter, the shortest in length, and the highest in SRL, but the fifth order roots were in reverse. The variance coefficients for the fine root diameter, root length, and SRL increased from the first to the fifth order roots. Except for the first order roots, soil depth had no significant influence on the fine root diameter, root length and SRL. Fertilization affected the fine root diameter, root length, and SRL of the first and the second order roots significantly, hut had little effects on other order roots. N fertilization decreased the mean diameter of the first and the second order roots significantly, and N or N + P fertilization decreased the mean length of the first order roots in surface soil (0-10 cm) significantly. The SRL of the first order roots in surface soil increased significantly under N fertilization.

  14. Corneal Subbasal Nerve Density: A Comparison of Two Confocal Microscopes

    Science.gov (United States)

    Erie, Elizabeth A.; McLaren, Jay W.; Kittleson, Katrina M.; Patel, Sanjay V.; Erie, Jay C.; Bourne, William M.

    2009-01-01

    Purpose To compare subbasal nerve densities estimated from images recorded by the Tandem Scanning and the ConfoScan 4 confocal microscopes. Methods Confocal microscopy was used to estimate subbasal nerve density in 62 corneas of 40 subjects (18 corneas of 18 normal subjects and 44 corneas of 22 patients between 1 and 12 months after LASIK) At each examination, corneas were scanned first by using Tandem Scanning and then by using a ConfoScan 4 confocal microscope. Subbasal nerves from 2 to 4 scans per cornea were traced by using a semi-automated nerve analysis program. Nerve density was expressed as total nerve length divided by the sample area (µm/mm2). Differences in nerve density between instruments were examined by using paired tests. Results In normal corneas, subbasal nerve density was 10,658 ± 5,581 µm/mm2 (mean ± SD) with the ConfoScan 4 and 5,534 ± 1,850 µm/mm2 with the Tandem Scanning microscope (Pmicroscope. These differences must be considered when comparing subbasal nerve densities between studies that use different confocal microscopes. PMID:18997541

  15. MODEL COMPARISON FOR THE DENSITY STRUCTURE ACROSS SOLAR CORONAL WAVEGUIDES

    Energy Technology Data Exchange (ETDEWEB)

    Arregui, I.; Asensio Ramos, A. [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Soler, R., E-mail: iarregui@iac.es [Solar Physics Group, Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

    2015-10-01

    The spatial variation of physical quantities, such as the mass density, across solar atmospheric waveguides governs the timescales and spatial scales for wave damping and energy dissipation. The direct measurement of the spatial distribution of density, however, is difficult, and indirect seismology inversion methods have been suggested as an alternative. We applied Bayesian inference, model comparison, and model-averaging techniques to the inference of the cross-field density structuring in solar magnetic waveguides using information on periods and damping times for resonantly damped magnetohydrodynamic transverse kink oscillations. Three commonly employed alternative profiles were used to model the variation of the mass density across the waveguide boundary. Parameter inference enabled us to obtain information on physical quantities such as the Alfvén travel time, the density contrast, and the transverse inhomogeneity length scale. The inference results from alternative density models were compared and their differences quantified. Then, the relative plausibility of the considered models was assessed by performing model comparison. Our results indicate that the evidence in favor of any of the three models is minimal, unless the oscillations are strongly damped. In such a circumstance, the application of model-averaging techniques enables the computation of an evidence-weighted inference that takes into account the plausibility of each model in the calculation of a combined inversion for the unknown physical parameters.

  16. Length-weight and Length-length Relationship of Longsnouted Catfish, Plicofollis argyropleuron (Valenciennes, 1840) in the Northern Part of Peninsular Malaysia

    Science.gov (United States)

    Rosli, Nor Aziella Mohd; Isa, Mansor Mat

    2012-01-01

    Scanty information exists pertaining to the length-weight relationship (LWR) and length-length relationship (LLR) parameters of longsnouted catfish, Plicofollis argyropleuron in lotic systems throughout the northern part of Peninsular Malaysia. It is vital to reveal these biological properties of P. argyropleuron in Kuala Muda and Merbok estuary for future management and to increase knowledge about this fish stocks. The fish samples were randomly collected in the estuary area of Kuala Muda and Merbok, Kedah for 10 months from March 2009 to December 2009. The values of the exponent b in the LWR equations (W = aLb) were approximately 3, indicating an isometric growth with high correlation coefficient (r2). The value of LLR (r2>0.9) indicated that they are highly significant and highly correlated. These parameters are essential for evaluating the relative condition of fish and species managements as well as their fisheries and stock assessment. PMID:24575234

  17. Study liquid length penetration results obtained with a direct acting piezo electric injector

    International Nuclear Information System (INIS)

    Payri, Raul; Gimeno, Jaime; Bardi, Michele; Plazas, Alejandro H.

    2013-01-01

    Highlights: ► A direct acting injector capable of controlling needle lift has been used to determine liquid phase penetration. ► The influence of injection pressure, chamber density and chamber temperature have been measured. ► When needle lift is reduced the stabilized liquid length is shortened. ► The relationship between needle lift and liquid length makes needle lift as a new way to control the injection event. - Abstract: A state of the art prototype common rail injector featuring direct control of the needle by means of a piezo stack (direct acting) has been tested. Liquid phase penetration of the sprays in diesel engine-like conditions has been studied via imaging technique in a novel continuous flow test chamber that allows an accurate control on a wide range of thermodynamic conditions (up to 1000 K and 15 MPa). This state of the art injector fitted with a 7-hole nozzle, allows a fully flexible control on the nozzle needle movement, enabling various fuel injection rate typologies. The temporal evolution of the seven sprays has been studied recording movies of the injection event in evaporative conditions via Mie scattering imaging technique and using a high speed camera. The results showed a strong influence of needle position on the stabilized liquid length while the effect of the injection pressure is negligible: the decrease of the needle lift causes a pressure drop in the needle seat and thus a reduction in the effective pressure upstream of the orifices (in the nozzle sac). According to known literature the stabilized liquid-length depends mainly on effective diameter, spray cone-angle and fuel/air properties and does not depend on fuel velocity at the orifice outlet. Therefore, due to small change in the spray cone-angle, higher injection pressures give slightly lower liquid length. However, partial needle lifts has an opposite effect: when needle is partially lifted a dramatic increase of the spray cone-angle and a consequent reduction of

  18. Franz Josef and Fox Glaciers, New Zealand: Historic length records

    Science.gov (United States)

    Purdie, Heather; Anderson, Brian; Chinn, Trevor; Owens, Ian; Mackintosh, Andrew; Lawson, Wendy

    2014-10-01

    Compilation of modern and historical length change records for Franz Josef and Fox Glaciers demonstrates that these glaciers have lost ~ 3 km in length and at least 3-4 km2 in area since the 1800s, with the greatest overall loss occurring between 1934 and 1983. Within this dramatic and ongoing retreat, both glaciers have experienced periods of re-advance. The record from Franz Josef Glacier is the most detailed, and shows major advances from 1946 to 1951 (340 m), 1965-1967 (400 m), 1983-1999 (1420 m) and 2004-2008 (280 m). At Fox Glacier the record is similar, with advances recorded during 1964-1968 (60 m), 1985-1999 (710 m) and 2004-2008 (290 m). Apart from the latest advance event, the magnitude of advance has been greater at Franz Josef Glacier, suggesting a higher length sensitivity. Analysis of the relationship between glacier length and a reconstructed annual equilibrium line altitude (ELA) record shows that the glaciers react very quickly to ELA variations - with the greatest correlation at 3-4 years' lag. The present (2014) retreat is the fastest retreat in the records of both glaciers. While decadal length fluctuations have been linked to hemispheric ocean-atmosphere variability, the overall reduction in length is a clear sign of twentieth century warming. However, documenting glacier length changes can be challenging; especially when increased surface debris-cover makes identification of the 'true' terminus a convoluted process.

  19. Microtubule length dependence of motor traffic in cells.

    Science.gov (United States)

    Zhang, Yunxin

    2012-10-01

    Motor proteins in living cells, such as kinesin and dynein, can move processively along the microtubule (MT), and can also detach from or attach to MT stochastically. Experiments found that the traffic of motors along MT may be jammed; thus various theoretical models were designed to understand this process. However, previous studies mainly focused on motor attachment/detachment rate dependent properties. Leduc et al. recently found that the traffic jam of motor protein Kip3 depends on MT length (Proc. Natl. Acad. Sci. U.S.A. 109, 6100 (2012)). Therefore, this study discusses the MT length-dependent properties of motor traffic. The results showed that MT length has one critical value N(c); a traffic jam occurs only when MT length N > N(c). The jammed MT length increases with total MT length N , whereas the non-jammed MT length may not change monotonically with N . The critical value N(c) increases with motor detachment rate from MT, but decreases with motor attachment rate to MT. Therefore, the traffic of motors will be more likely to be jammed when the MT is long, motor detachment rate is high, and motor detachment rate is low.

  20. The relationship between telomere length and beekeeping among Malaysians.

    Science.gov (United States)

    Nasir, Nurul Fatihah Mohamad; Kannan, Thirumulu Ponnuraj; Sulaiman, Siti Amrah; Shamsuddin, Shaharum; Azlina, Ahmad; Stangaciu, Stefan

    2015-06-01

    The belief that beekeepers live longer than anyone else is present since ages. However, no research has been done to explore the longevity of life in beekeepers. Here, we investigated the telomere length in 30 male beekeepers and 30 male non-beekeepers and associated them with the longevity of life using Southern analysis of terminal restriction fragments (TRFs) generated by Hinf I/Rsa I digestion of human genomic DNA using TeloTAGGG Telomere Length Assay. Interestingly, we found that the telomere length of male beekeepers was significantly longer than those of male non-beekeepers with a p value of less than 0.05, suggesting that beekeepers may have longer life compared to non-beekeepers. We further found that the consumption of bee products for a long period and frequent consumption of bee products per day are associated with telomere length. An increase of year in consuming bee products is associated with a mean increase in telomere length of 0.258 kbp. In addition, an increase in frequency of eating bee products per day was also associated with a mean increase of 2.66 kbp in telomere length. These results suggested that bee products might play some roles in telomere length maintenance.