Sociodemographic factors influencing the use of injections in South Korean outpatient care.

PubMed

Lee, Iyn-Hyang; Park, Sylvia; Lee, Eui-Kyung

2014-01-01

This study explored the relationship between sociodemographic factors and injection utilization in South Korea. We conducted a retrospective cross-sectional analysis using 2009 prescription claims for Korean National Health Insurance beneficiaries. We analyzed the utilization, costs, and proportion of injections in the insured market for oral-injection dual-dose-form ingredients (DFIs). We included outpatients who were prescribed DFIs with no age limits. Descriptive analysis and multivariate logistic regression were performed to evaluate the predictive factors of injection use. Injections accounted for about 5% of outpatient utilization and costs of the study drugs. The odds of having injections were 1.3-1.6 times higher among those patients who are 70 years and older compared with those in the 20s, in smaller-sized hospitals and clinics than that in larger, and among medical institutions in rural areas than those in the capital area. The odds of having injections were increased stepwise for the age groups of 30-69 years. Injections were more likely to be prescribed for systematic hormonal preparations and drugs for the musculoskeletal system. The use of injections was higher among older groups, among smaller medical institutions, and among institutions in rural areas in Korean outpatient care. The difference between prescribing defined daily doses and prescribing rate for injections of the audit reports implies that Korean doctors prescribed injections often, but small doses for momentary effects in outpatient settings. Further studies are required to uncover the underlying causes of the high prevalence of injection use in older or rural populations and smaller institutions. Copyright © 2012 John Wiley & Sons, Ltd.

Predictive variables for the biological behaviour of basal cell carcinoma of the face: relevance of morphometry of the nuclei.

PubMed

Appel, T; Bierhoff, E; Appel, K; von Lindern, J-J; Bergé, S; Niederhagen, B

2003-06-01

We did a morphometric analysis of 130 histological sections of basal cell carcinoma (BCC) of the face to find out whether morphometric variables in the structure of the nuclei of BCC cells could serve as predictors of the biological behaviour. We considered the following variables: maximum and minimum diameters, perimeter, nuclear area and five form factors that characterise and quantify the shape of a structure (axis ratio, shape factor, nuclear contour index, nuclear roundness and circumference ratio). We did a statistical analysis of primary and recurring tumours and four histology-based groups (multifocal superficial BCCs, nodular BCCs, sclerosing BCCs and miscellaneous forms) using a two-sided t test for independent samples. Multifocal superficial BCCs showed significantly smaller values for the directly measured variables (maximum and minimum diameters, perimeter and nuclear area). Morphometry could not distinguish between primary and recurring tumours.

Molecular-like hierarchical self-assembly of monolayers of mixtures of particles

PubMed Central

Singh, P.; Hossain, M.; Gurupatham, S. K.; Shah, K.; Amah, E.; Ju, D.; Janjua, M.; Nudurupati, S.; Fischer, I.

2014-01-01

We present a technique that uses an externally applied electric field to self-assemble monolayers of mixtures of particles into molecular-like hierarchical arrangements on fluid-liquid interfaces. The arrangements consist of composite particles (analogous to molecules) which are arranged in a pattern. The structure of a composite particle depends on factors such as the relative sizes of the particles and their polarizabilities, and the electric field intensity. If the particles sizes differ by a factor of two or more, the composite particle has a larger particle at its core and several smaller particles form a ring around it. The number of particles in the ring and the spacing between the composite particles depend on their polarizabilities and the electric field intensity. Approximately same sized particles form chains (analogous to polymeric molecules) in which positively and negatively polarized particles alternate. PMID:25510331

Volatility of methylglyoxal cloud SOA formed through OH radical oxidation and droplet evaporation

NASA Astrophysics Data System (ADS)

Ortiz-Montalvo, Diana L.; Schwier, Allison N.; Lim, Yong B.; McNeill, V. Faye; Turpin, Barbara J.

2016-04-01

The volatility of secondary organic aerosol (SOA) formed through cloud processing (aqueous hydroxyl radical (radOH) oxidation and droplet evaporation) of methylglyoxal (MGly) was studied. Effective vapor pressure and effective enthalpy of vaporization (ΔHvap,eff) were determined using 1) droplets containing MGly and its oxidation products, 2) a Vibrating Orifice Aerosol Generator (VOAG) system, and 3) Temperature Programmed Desorption Aerosol-Chemical Ionization Mass Spectrometry (TPD Aerosol-CIMS). Simulated in-cloud MGly oxidation (for 10-30 min) produces an organic mixture of higher and lower volatility components with an overall effective vapor pressure of (4 ± 7) × 10-7 atm at pH 3. The effective vapor pressure decreases by a factor of 2 with addition of ammonium hydroxide (pH 7). The fraction of organic material remaining in the particle-phase after drying was smaller than for similar experiments with glycolaldehyde and glyoxal SOA. The ΔHvap,eff of pyruvic acid and oxalic acid + methylglyoxal in the mixture (from TPD Aerosol-CIMS) were smaller than the theoretical enthalpies of the pure compounds and smaller than that estimated for the entire precursor/product mix after droplet evaporation. After 10-30 min of aqueous oxidation (one cloud cycle) the majority of the MGly + radOH precursor/product mix (even neutralized) will volatilize during droplet evaporation; neutralization and at least 80 min of oxidation at 10-12 M radOH (or >12 h at 10-14 M) is needed before low volatility ammonium oxalate exceeds pyruvate.

Study of the in-medium nucleon electromagnetic form factors using a light-front nucleon wave function combined with the quark-meson coupling model

NASA Astrophysics Data System (ADS)

de Araújo, W. R. B.; de Melo, J. P. B. C.; Tsushima, K.

2018-02-01

We study the nucleon electromagnetic (EM) form factors in symmetric nuclear matter as well as in vacuum within a light-front approach using the in-medium inputs calculated by the quark-meson coupling model. The same in-medium quark properties are used as those used for the study of in-medium pion properties. The zero of the proton EM form factor ratio in vacuum, the electric to magnetic form factor ratio μpGEp (Q2) /GMp (Q2) (Q2 = -q2 > 0 with q being the four-momentum transfer), is determined including the latest experimental data by implementing a hard constituent quark component in the nucleon wave function. A reasonable fit is achieved for the ratio μpGEp (Q2) /GMp (Q2) in vacuum, and we predict that the Q02 value to cross the zero of the ratio to be about 15 GeV2. In addition the double ratio data of the proton EM form factors in 4He and H nuclei, [GEp4He (Q2) /G4HeMp (Q2) ] / [GEp1H (Q2) /GMp1H (Q2) ], extracted by the polarized (e → ,e‧ p →) scattering experiment on 4He at JLab, are well described. We also predict that the Q02 value satisfying μpGEp (Q02) /GMp (Q0 2) = 0 in symmetric nuclear matter, shifts to a smaller value as increasing nuclear matter density, which reflects the facts that the faster falloff of GEp (Q2) as increasing Q2 and the increase of the proton mean-square charge radius. Furthermore, we calculate the neutron EM form factor double ratio in symmetric nuclear matter for 0.1

Replica-exchange molecular dynamics simulation of basic fibroblast growth factor adsorption on hydroxyapatite.

PubMed

Liao, Chenyi; Zhou, Jian

2014-06-05

The adsorption of basic fibroblast growth factor (bFGF) on the hydroxyapatite (001) surface was investigated by a combination of replica-exchange molecular dynamics (REMD) and conventional molecular dynamics (CMD) methods. In CMD, the protein cannot readily cross the surface water layer, whereas in REMD, the protein can cross the adsorption barrier from the surface water layer and go through weak, medium, then strong adsorption states with three energetically preferred configurations: heparin-binding-up (HP-up), heparin-binding-middle (HP-middle), and heparin-binding-down (HP-down). The HP-middle orientation, with the strongest adsorption energy (-1149 ± 40 kJ·mol(-1)), has the largest adsorption population (52.1-52.6%) and exhibits the largest conformational charge (RMSD of 0.26 ± 0.01 nm) among the three orientations. The HP-down and HP-up orientations, with smaller adsorption energies of -1022 ± 55 and -894 ± 70 kJ·mol(-1), respectively, have smaller adsorption populations of 27.4-27.7% and 19.7-20.5% and present smaller RMSD values of 0.21 ± 0.01 and 0.19 ± 0.01 nm, respectively. The convergent distribution indicates that nearly half of the population (in the HP-middle orientation) will support both FGF/FGFR and DGR-integrin signaling and another half (in the HP-up and HP-down orientations) will support DGR-integrin signaling. The major population (~80%) has the protein dipole directed outward. In the strong adsorption state, there are usually 2 to 3 basic residues that form the anchoring interactions of 210-332 kJ·mol(-1) per residue or that are accompanied by an acidic residue with an adsorption energy of ~207 kJ·mol(-1). Together, the major bound residues form a triangle or a quadrilateral on the surface and stabilize the adsorption geometrically, which indicates topologic matching between the protein and HAP surfaces.

Implications of recent measurements of hadronic charmless B decays

NASA Astrophysics Data System (ADS)

Cheng, Hai-Yang; Yang, Kwei-Chou

2000-09-01

The implications of recent CLEO measurements of hadronic charmless B decays are discussed. (i) Employing the Bauer-Stech-Wirbel (BSW) model for form factors as a benchmark, the B-->π+π- data indicate that the form factor FBπ0(0) is smaller than that predicted by the BSW model, whereas the data of B-->ωπ, K*η imply that the form factors ABω0(0), ABK*0(0) are greater than the BSW model values. (ii) The tree-dominated modes B-->π+π-, ρ0π+/-, ωπ+/- imply that the effective number of colors Neffc(LL) for (V-A)(V-A) operators is preferred to be smaller, while the current limit on B-->φK shows that Neffc(LR)>3. The data of B-->Kη' and K*η clearly indicate that Neffc(LR)>>Neffc(LL). (iii) In order to understand the observed suppression of π+π- and nonsuppression of Kπ modes, both being governed by the form factor FBπ0, the unitarity angle γ is preferred to be greater than 90°. By contrast, the new measurement of B+/--->ρ0π+/- no longer strongly favors cos γ<0. (iv) The observed pattern K-π+~K¯0π-~23K-π0 is consistent with the theoretical expectation: The constructive interference between electroweak and QCD penguin diagrams in the K-π0 mode explains why B(B--->K-π0)>12B(B¯0-->K-π+). (v) The observation Neffc(LL)<3η'K and ηK* data. (vii) The new upper limit set for B--->ωK- no longer imposes a serious problem for the factorization approach. It is anticipated that B(B--->ωK-)>~2B(B--->ρ0K-)~2×10-6. (viii) An improved and refined measurement of B-->K*-π+, K¯0π0 is called for in order to resolve the discrepancy between theory and experiment. Theoretically, it is expected that K¯0π0~12 K-π0 and K-π+~3 K*-π+.

Mathematical Simulation for Integrated Linear Fresnel Spectrometer Chip

NASA Technical Reports Server (NTRS)

Park, Yeonjoon; Yoon, Hargoon; Lee, Uhn; King, Glen C.; Choi, Sang H.

2012-01-01

A miniaturized solid-state optical spectrometer chip was designed with a linear gradient-gap Fresnel grating which was mounted perpendicularly to a sensor array surface and simulated for its performance and functionality. Unlike common spectrometers which are based on Fraunhoffer diffraction with a regular periodic line grating, the new linear gradient grating Fresnel spectrometer chip can be miniaturized to a much smaller form-factor into the Fresnel regime exceeding the limit of conventional spectrometers. This mathematical calculation shows that building a tiny motionless multi-pixel microspectrometer chip which is smaller than 1 cubic millimter of optical path volume is possible. The new Fresnel spectrometer chip is proportional to the energy scale (hc/lambda), while the conventional spectrometers are proportional to the wavelength scale (lambda). We report the theoretical optical working principle and new data collection algorithm of the new Fresnel spectrometer to build a compact integrated optical chip.

Orbital evolution and accretion of protoplanets tidally interacting with a gas disk. II. Solid surface density evolution with type-I migration

NASA Astrophysics Data System (ADS)

Daisaka, Junko K.; Tanaka, Hidekazu; Ida, Shigeru

2006-12-01

This paper investigates the surface density evolution of a planetesimal disk due to the effect of type-I migration by carrying out N-body simulation and through analytical method, focusing on terrestrial planet formation. The coagulation and the growth of the planetesimals take place in the abundant gas disk except for a final stage. A protoplanet excites density waves in the gas disk, which causes the torque on the protoplanet. The torque imbalance makes the protoplanet suffer radial migration, which is known as type-I migration. Type-I migration time scale derived by the linear theory may be too short for the terrestrial planets to survive, which is one of the major problems in the planet formation scenario. Although the linear theory assumes a protoplanet being in a gas disk alone, Kominami et al. [Kominami, J., Tanaka, H., Ida, S., 2005. Icarus 167, 231-243] showed that the effect of the interaction with the planetesimal disk and the neighboring protoplanets on type-I migration is negligible. The migration becomes pronounced before the planet's mass reaches the isolation mass, and decreases the solid component in the disk. Runaway protoplanets form again in the planetesimal disk with decreased surface density. In this paper, we present the analytical formulas that describe the evolution of the solid surface density of the disk as a function of gas-to-dust ratio, gas depletion time scale and semimajor axis, which agree well with our results of N-body simulations. In general, significant depletion of solid material is likely to take place in inner regions of disks. This might be responsible for the fact that there is no planet inside Mercury's orbit in our Solar System. Our most important result is that the final surface density of solid components ( Σ) and mass of surviving planets depend on gas surface density ( Σ) and its depletion time scale ( τ) but not on initial Σ; they decrease with increase in Σ and τ. For a fixed gas-to-dust ratio and τ, larger initial Σ results in smaller final Σ and smaller surviving planets, because of larger Σ. To retain a specific amount of Σ, the efficient disk condition is not an initially large Σ but the initial Σ as small as the specified final one and a smaller gas-to-dust ratio. To retain Σ comparable to that of the minimum mass solar nebula (MMSN), a disk must have the same Σ and a gas-to-dust ratio that is smaller than that of MMSN by a factor of 1.3×(τ/1 Myr) at ˜1 AU. (Equivalently, type-I migration speed is slower than that predicted by the linear theory by the same factor.) The surviving planets are Mars-sized ones in this case; in order to form Earth-sized planets, their eccentricities must be pumped up to start orbit crossing and coagulation among them. At ˜5 AU, Σ of MMSN is retained under the same condition, but to form a core massive enough to start runaway gas accretion, a gas-to-dust ratio must be smaller than that of MMSN by a factor of 3×τ/1 Myr.

Regulation of Mitochondrial Structure and Dynamics by the Cytoskeleton and Mechanical Factors.

PubMed

Bartolák-Suki, Erzsébet; Imsirovic, Jasmin; Nishibori, Yuichiro; Krishnan, Ramaswamy; Suki, Béla

2017-08-21

Mitochondria supply cells with energy in the form of ATP, guide apoptosis, and contribute to calcium buffering and reactive oxygen species production. To support these diverse functions, mitochondria form an extensive network with smaller clusters that are able to move along microtubules aided by motor proteins. Mitochondria are also associated with the actin network, which is involved in cellular responses to various mechanical factors. In this review, we discuss mitochondrial structure and function in relation to the cytoskeleton and various mechanical factors influencing cell functions. We first summarize the morphological features of mitochondria with an emphasis on fission and fusion as well as how network properties govern function. We then review the relationship between the mitochondria and the cytoskeletal structures, including mechanical interactions. We also discuss how stretch and its dynamic pattern affect mitochondrial structure and function. Finally, we present preliminary data on how extracellular matrix stiffness influences mitochondrial morphology and ATP generation. We conclude by discussing the more general role that mitochondria may play in mechanobiology and how the mechanosensitivity of mitochondria may contribute to the development of several diseases and aging.

Regulation of Mitochondrial Structure and Dynamics by the Cytoskeleton and Mechanical Factors

PubMed Central

Bartolák-Suki, Erzsébet; Imsirovic, Jasmin; Nishibori, Yuichiro; Krishnan, Ramaswamy; Suki, Béla

2017-01-01

Mitochondria supply cells with energy in the form of ATP, guide apoptosis, and contribute to calcium buffering and reactive oxygen species production. To support these diverse functions, mitochondria form an extensive network with smaller clusters that are able to move along microtubules aided by motor proteins. Mitochondria are also associated with the actin network, which is involved in cellular responses to various mechanical factors. In this review, we discuss mitochondrial structure and function in relation to the cytoskeleton and various mechanical factors influencing cell functions. We first summarize the morphological features of mitochondria with an emphasis on fission and fusion as well as how network properties govern function. We then review the relationship between the mitochondria and the cytoskeletal structures, including mechanical interactions. We also discuss how stretch and its dynamic pattern affect mitochondrial structure and function. Finally, we present preliminary data on how extracellular matrix stiffness influences mitochondrial morphology and ATP generation. We conclude by discussing the more general role that mitochondria may play in mechanobiology and how the mechanosensitivity of mitochondria may contribute to the development of several diseases and aging. PMID:28825689

Field-reversed configuration (FRC) experiments

NASA Astrophysics Data System (ADS)

Siemon, R. E.; Chrien, R. E.; Hugrass, W. N.; Okada, S.; Rej, D. J.; Taggart, D. P.; Tuszewski, M.; Webster, R. B.; Wright, B. L.; Slough, J. T.

FRCs with equilibrium separatrix radii up to 0.18 m have been formed and studied in FRX-C/LSM. For best formation conditions at low fill pressure, the particle confinement exceeds the predictions of LHD transport calculations by up to a factor of two; however, the inferred flux confinement is more anomalous than in smaller FRCs. Higher bias field produces axial shocks and degradation in confinement, while higher fill pressure results in gross fluting during formation. FRCs have been formed in TRX with s from 2 to 6. These relatively collisional FRCs exhibit flux lifetimes of 10 yields 20 kinetic growth times for the internal tilt mode. The coaxial slow source has produced annular FRCs in a coaxial coil geometry on slow time scales using low voltages.

Small form factor optical fiber connector evaluation for harsh environments

NASA Astrophysics Data System (ADS)

Ott, Melanie N.; Thomes, W. Joe, Jr.; Chuska, Richard F.; Switzer, Robert; Blair, Diana E.

2011-09-01

For the past decade NASA programs have utilized the Diamond AVIM connector for optical fiber assemblies on space flight instrumentation. These connectors have been used in communications, sensing and LIDAR systems where repeatability and high performance are required. Recently Diamond has released a smaller form factor optical fiber connector called the "Mini-AVIM" which although more compact still includes the tight tolerances and the ratcheting feature of the heritage AVIM. NASA Goddard Space Flight Center Photonics Group in the Parts, Packaging and Assembly Technologies Office has been performing evaluations of this connector to determine how it compares to the performance of the AVIM connector and to assess its feasibility for harsh environmental applications. Vibration and thermal testing were performed on the Mini-AVIM with both multi-mode and single-mode optical fiber using insitu optical transmission monitoring. Random vibration testing was performed using typical launch condition profiles for most NASA missions but extended to 35 Grms, which is much higher than most requirements. Thermal testing was performed incrementally up to a range of -55°C to +125°C. The test results include both unjacketed fiber and cabled assembly evaluations. The data presented here indicate that the Mini-AVIM provides a viable option for small form factor applications that require a high performance optical fiber connector.

High performance quarter-inch cartridge tape systems

NASA Technical Reports Server (NTRS)

Schwarz, Ted

1993-01-01

Within the established low cost structure of Data Cartridge drive technology, it is possible to achieve nearly 1 terrabyte (10(exp 12)) of data capacity and more than 1 Gbit/sec (greater than 100 Mbytes/sec) transfer rates. The desirability to place this capability within a single cartridge will be determined by the market. The 3.5 in. or smaller form factor may suffice to serve both the current Data Cartridge market and a high performance segment. In any case, Data Cartridge Technology provides a strong sustainable technology growth path in the 21st century.

Expression of genomic AtCYCD2;1 in Arabidopsis induces cell division at smaller cell sizes: implications for the control of plant growth.

PubMed

Qi, Ruhu; John, Peter Crook Lloyd

2007-07-01

The Arabidopsis (Arabidopsis thaliana) CYCD2;1 gene introduced in genomic form increased cell formation in the Arabidopsis root apex and leaf, while generating full-length mRNA, raised CDK/CYCLIN enzyme activity, reduced G1-phase duration, and reduced size of cells at S phase and division. Other cell cycle genes, CDKA;1, CYCLIN B;1, and the cDNA form of CYCD2;1 that produced an aberrantly spliced mRNA, produced smaller or zero increases in CDK/CYCLIN activity and did not increase the number of cells formed. Plants with a homozygous single insert of genomic CYCD2;1 grew with normal morphology and without accelerated growth of root or shoot, not providing evidence that cell formation or CYCLIN D2 controls growth of postembryonic vegetative tissues. At the root apex, cells progressed normally from meristem to elongation, but their smaller size enclosed less growth and a 40% reduction in final size of epidermal and cortical cells was seen. Smaller elongated cell size inhibited endoreduplication, indicating a cell size requirement. Leaf cells were also smaller and more numerous during proliferation and epidermal pavement and palisade cells attained 59% and 69% of controls, whereas laminas reached normal size. Autonomous control of expansion was therefore not evident in abundant cell types that formed tissues of root or leaf. Cell size was reduced by a greater number formed in a tissue prior to cell and tissue expansion. Initiation and termination of expansion did not correlate with cell dimension or number and may be determined by tissue-wide signals acting across cellular boundaries.

Impact of the Fano Factor on Position and Energy Estimation in Scintillation Detectors.

PubMed

Bora, Vaibhav; Barrett, Harrison H; Jha, Abhinav K; Clarkson, Eric

2015-02-01

The Fano factor for an integer-valued random variable is defined as the ratio of its variance to its mean. Light from various scintillation crystals have been reported to have Fano factors from sub-Poisson (Fano factor < 1) to super-Poisson (Fano factor > 1). For a given mean, a smaller Fano factor implies a smaller variance and thus less noise. We investigated if lower noise in the scintillation light will result in better spatial and energy resolutions. The impact of Fano factor on the estimation of position of interaction and energy deposited in simple gamma-camera geometries is estimated by two methods - calculating the Cramér-Rao bound and estimating the variance of a maximum likelihood estimator. The methods are consistent with each other and indicate that when estimating the position of interaction and energy deposited by a gamma-ray photon, the Fano factor of a scintillator does not affect the spatial resolution. A smaller Fano factor results in a better energy resolution.

Radiation response of oxide-dispersion-strengthened alloy MA956 after self-ion irradiation

NASA Astrophysics Data System (ADS)

Chen, Tianyi; Kim, Hyosim; Gigax, Jonathan G.; Chen, Di; Wei, Chao-Chen; Garner, F. A.; Shao, Lin

2017-10-01

We studied the radiation-induced microstructural evolution of an oxide-dispersion-strengthened (ODS) ferritic alloy, MA956, to 180 dpa using 3.5 MeV Fe2+ ions. Post-irradiation examination showed that voids formed rather early and almost exclusively at the particle-matrix interfaces. Surprisingly, voids formed even in the injected interstitial zone. Comparisons with studies on other ODS alloys with smaller and largely coherent dispersoids irradiated at similar conditions revealed that the larger and not completely coherent oxide particles in MA956 serve as defect collectors which promote nucleation of voids at their interface. The interface configuration, which is related to particle type, crystal structure and size, is one of the important factors determining the defect-sink properties of particle-matrix interfaces.

Measuring size evolution of distant, faint galaxies in the radio regime

NASA Astrophysics Data System (ADS)

Lindroos, L.; Knudsen, K. K.; Stanley, F.; Muxlow, T. W. B.; Beswick, R. J.; Conway, J.; Radcliffe, J. F.; Wrigley, N.

2018-05-01

We measure the evolution of sizes for star-forming galaxies as seen in 1.4 GHz continuum radio for z = 0-3. The measurements are based on combined VLA+MERLIN data of the Hubble Deep Field, and using a uv-stacking algorithm combined with model fitting to estimate the average sizes of galaxies. A sample of ˜1000 star-forming galaxies is selected from optical and near-infrared catalogues, with stellar masses M⊙ ≈ 1010-1011 M⊙ and photometric redshifts 0-3. The median sizes are parametrized for stellar mass M* = 5 × 1010 M⊙ as R_e = A× {}(H(z)/H(1.5))^{α _z}. We find that the median radio sizes evolve towards larger sizes at later times with αz = -1.1 ± 0.6, and A (the median size at z ≈ 1.5) is found to be 0.26^'' ± 0.07^'' or 2.3±0.6 kpc. The measured radio sizes are typically a factor of 2 smaller than those measure in the optical, and are also smaller than the typical H α sizes in the literature. This indicates that star formation, as traced by the radio continuum, is typically concentrated towards the centre of galaxies, for the sampled redshift range. Furthermore, the discrepancy of measured sizes from different tracers of star formation, indicates the need for models of size evolution to adopt a multiwavelength approach in the measurement of the sizes star-forming regions.

Foliar stable carbon and nitrogen isotopes in woody Mediterranean species with different life form and post-fire regeneration.

PubMed

Saura-Mas, S; Lloret, F

2010-01-01

Wildfire is an important ecological disturbance factor in most Mediterranean ecosystems. In the Mediterranean Basin, most shrub species can regenerate after fire by resprouting or seeding. Here, we hypothesize that post-fire regenerative syndromes may potentially co-vary with traits directly related to functional properties involved in resource use. Thus, seeders with a shorter life span and smaller size would have lower water-use efficiency (WUE) than re-sprouting species and would take up nutrients such as nitrogen from more superficial parts of the soil. To test this hypothesis, we compared leaf (13)C and (15)N signatures from 29 co-existing species with different post-fire regeneration strategies. We also considered life form as an additional explanatory variable of the differences between post-fire regenerative groups. Our data support the hypothesis that seeder species (which mostly evolved in the Quaternary under a Mediterranean climate) have lower WUE and less stomatal control than non-seeders (many of which evolved under different climatic conditions in the Tertiary) and consequently greater consumption of water per unit biomass. This would be related to their smaller life forms, which tend to have lower WUE and shorter life and leaf lifespan. Differences in (15)N also support the hypothesis that resprouters have deeper root systems than non-resprouters. The study supports the hypothesis of an overlap between plant functional traits and plant attributes describing post-disturbance resilience.

Organizational characteristics influence implementation of worksite health protection and promotion programs: Evidence from smaller businesses

PubMed Central

McLellan, Deborah L.; Cabán-Martinez, Alberto J.; Nelson, Candace C.; Pronk, Nicolaas P.; Katz, Jeffrey N.; Allen, Jennifer D.; Davis, Kia L.; Wagner, Gregory R.; Sorensen, Glorian

2015-01-01

Objective We explored associations between organizational factors (size, sector, leadership support, and organizational capacity) and implementation of Occupational Safety and Health (OSH) and Worksite Health Promotion (WHP) programs in smaller businesses. Methods We conducted a web-based survey of Human Resource Managers of 117 smaller businesses (<750 employees) and analyzed factors associated with implementation of OSH and WHP among these sites using multivariate analyses. Results Implementation of OSH but not WHP activities were related to industry sector (p= 0.003). Leadership support was positively associated with OSH activities (p<.001), but negatively associated with WHP implementation. Organizational capacity (budgets, staffing, and committee involvement) was associated with implementation of both OSH and WHP. Size was related to neither. Conclusions Leadership support and specifically allocated resources reflecting that support are important factors for implementing OSH and WHP in smaller organizations. PMID:26340290

Structures of Staphylococcus aureus D-tagatose-6-phosphate kinase implicate domain motions in specificity and mechanism.

PubMed

Miallau, Linda; Hunter, William N; McSweeney, Sean M; Leonard, Gordon A

2007-07-06

High resolution structures of Staphylococcus aureus d-tagatose-6-phosphate kinase (LacC) in two crystal forms are herein reported. The structures define LacC in apoform, in binary complexes with ADP or the co-factor analogue AMP-PNP, and in a ternary complex with AMP-PNP and D-tagatose-6-phosphate. The tertiary structure of the LacC monomer, which is closely related to other members of the pfkB subfamily of carbohydrate kinases, is composed of a large alpha/beta core domain and a smaller, largely beta "lid." Four extended polypeptide segments connect these two domains. Dimerization of LacC occurs via interactions between lid domains, which come together to form a beta-clasp structure. Residues from both subunits contribute to substrate binding. LacC adopts a closed structure required for phosphoryl transfer only when both substrate and co-factor are bound. A reaction mechanism similar to that used by other phosphoryl transferases is proposed, although unusually, when both substrate and co-factor are bound to the enzyme two Mg(2+) ions are observed in the active site. A new motif of amino acid sequence conservation common to the pfkB subfamily of carbohydrate kinases is identified.

GpIIb/IIIa+ subpopulation of rat megakaryocyte progenitor cells exhibits high responsiveness to human thrombopoietin.

PubMed

Kato, T; Horie, K; Hagiwara, T; Maeda, E; Tsumura, H; Ohashi, H; Miyazaki, H

1996-08-01

The recently cloned factor thrombopoietin (TPO) has been shown to exhibit megakaryocyte colony-stimulating activity in vitro. In this investigation, to further evaluate the action of TPO on megakaryocyte progenitor cells (colony-forming units-megakaryocyte [CFU-MK]), GpIIb/IIIa+ and GpIIb/IIIa- populations of CFU-MK were prepared from rat bone marrow cells based on their reactivity with P55 antibody, a monoclonal antibody against rat GpIIb/IIIa, and their responsiveness to recombinant human TPO (rhTPO) and recombinant rat interleukin-3 (rrIL-3) was examined using a megakaryocyte colony-forming assay (Meg-CSA). rhTPO supported only megakaryocyte colony growth from both fractions in a dose-dependent fashion. The mean colony size observed with the GpIIb/IIIa+ population was smaller than that seen with the GpIIb/IIIa- population. With the optimal concentration of either rhTPO or rrIL-3, similar numbers of megakaryocyte colonies were formed from the GpIIb/IIIa+ population previously shown to be highly enriched for CFU-MK. In contrast, the maximum number of megakaryocyte colonies from the GpIIb/IIIa- population stimulated by rhTPO was only 24.2% of that achieved with rrIL-3. Morphologic analysis of rhTPO-promoted megakaryocyte colonies from the GpIIb/IIIa+ population showed that the average colony size was smaller but that the mean diameter of individual megakaryocytes was larger than in megakaryocyte colonies promoted with rrIL-3. rhTPO plus rrIL-3, each at suboptimal concentrations, had an additive effect on proliferation of CFU-MK in the GpIIb/IIIa+ fraction, whereas rhTPO plus murine IL-6 or murine granulocyte-macrophage colony-stimulating factor (mG-M-CSF) modestly but significantly reduced megakaryocyte colony growth. These results indicate that TPO preferentially acts on GpIIb/IIIa+ late CFU-MK with lower proliferative capacity and interacts with some other cytokines in CFU-MK development.

Coherent convergent-beam time-resolved X-ray diffraction

PubMed Central

Spence, John C. H.; Zatsepin, Nadia A.; Li, Chufeng

2014-01-01

The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. PMID:24914153

Hardware and software implementation of a low power attitude control and determination system for cubesats

NASA Astrophysics Data System (ADS)

Frey, Jesse

In recent years there has been a growing interest in smaller satellites. Smaller satellites are cheaper to build and launch than larger satellites. One form factor, the CubeSat, is especially popular with universities and is a 10~cm cube. Being smaller means that the mass and power budgets are tighter and as such new ways must be developed to cope with these constraints. Traditional attitude control systems often use reaction wheels with gas thrusters which present challenges on a CubeSat. Many CubeSats use magnetic attitude control which uses the Earth's magnetic field to torque the satellite into the proper orientation. Magnetic attitude control systems fall into two main categories: active and passive. Active control is often achieved by running current through a coil to produce a dipole moment, while passive control uses the dipole moment from permanent magnets that consume no power. This thesis describes a system that uses twelve hard magnetic torquers along with a magnetometer. The torquers only consume current when their dipole moment is flipped, thereby significantly reducing power requirements compared with traditional active control. The main focus of this thesis is on the design, testing and fabrication of CubeSat hardware and software in preparation for launch.

Local capacity for groundwater protection in Ontario.

PubMed

De Loë, Rob C; Di Giantomasso, Sandra E; Kreutzwiser, Reid D

2002-02-01

Preventing groundwater contamination is vastly cheaper than remediation. Recognizing this, attention in water and land management agencies in North America increasingly turn to groundwater protection. Local agencies, such as municipalities and watershed management districts, are vital to successful groundwater protection, but they face daunting challenges. In the United States, senior governments have recognized these challenges and provide considerable support for local agencies. In Ontario, Canada, local agencies are, to a much greater extent, on their own. The aims in this paper are to analyze factors that shape local capacity for groundwater protection, focusing on Ontario, and to recommend avenues for capacity building. Interrelationships among five dimensions of capacity (technical, financial, institutional, social, and political) are explored through an analysis of three smaller Ontario communities: City of Guelph (population 93,400), Town of Orangeville (population 22,188), and Town of Erin (population 11,000). Size clearly influences capacity for groundwater protection. However, other considerations unrelated to size appear to be as important. These other factors include the ability to form horizontal and vertical linkages with external agencies, political leadership and commitment, and citizen involvement. Thus, smaller communities in Ontario (and other jurisdictions with limited senior government support) would do well to focus on these areas at the same time as they develop their technical, financial, and institutional capacity.

Microbial community variation in cryoconite granules on Qaanaaq Glacier, NW Greenland.

PubMed

Uetake, Jun; Tanaka, Sota; Segawa, Takahiro; Takeuchi, Nozomu; Nagatsuka, Naoko; Motoyama, Hideaki; Aoki, Teruo

2016-09-01

Cryoconite granules are aggregations of microorganisms with mineral particles that form on glacier surfaces. To understand the processes by which the granules develop, this study focused on the altitudinal distribution of the granules and photosynthetic microorganisms on the glacier, bacterial community variation with granules size and environmental factors affecting the growth of the granules. Size-sorted cryoconite granules collected from five different sites on Qaanaaq Glacier were analyzed. C and N contents were significantly higher in large (diameter greater than 250 μm) granules than in smaller (diameter 30-249 μm) granules. Bacterial community structures, based on 16S rRNA gene amplicon sequencing, were different between the smaller and larger granules. The filamentous cyanobacterium Phormidesmis priestleyi was the dominant bacterial species in larger granules. Multivariate analysis suggests that the abundance of mineral particles on the glacier surface is the main factor controlling growth of these cyanobacteria. These results show that the supply of mineral particles on the glacier enhances granule development, that P. priestleyi is likely the key species for primary production and the formation of the granules and that the bacterial community in the granules changes over the course of the granule development. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Discrimination of bed form scales using robust spline filters and wavelet transforms: Methods and application to synthetic signals and bed forms of the Río Paraná, Argentina

NASA Astrophysics Data System (ADS)

Gutierrez, Ronald R.; Abad, Jorge D.; Parsons, Daniel R.; Best, James L.

2013-09-01

There is no standard nomenclature and procedure to systematically identify the scale and magnitude of bed forms such as bars, dunes, and ripples that are commonly present in many sedimentary environments. This paper proposes a standardization of the nomenclature and symbolic representation of bed forms and details the combined application of robust spline filters and continuous wavelet transforms to discriminate these morphodynamic features, allowing the quantitative recognition of bed form hierarchies. Herein the proposed methodology for bed form discrimination is first applied to synthetic bed form profiles, which are sampled at a Nyquist ratio interval of 2.5-50 and a signal-to-noise ratio interval of 1-20 and subsequently applied to a detailed 3-D bed topography from the Río Paraná, Argentina, which exhibits large-scale dunes with superimposed, smaller bed forms. After discriminating the synthetic bed form signals into three-bed form hierarchies that represent bars, dunes, and ripples, the accuracy of the methodology is quantified by estimating the reproducibility, the cross correlation, and the standard deviation ratio of the actual and retrieved signals. For the case of the field measurements, the proposed method is used to discriminate small and large dunes and subsequently obtain and statistically analyze the common morphological descriptors such as wavelength, slope, and amplitude of both stoss and lee sides of these different size bed forms. Analysis of the synthetic signals demonstrates that the Morlet wavelet function is the most efficient in retrieving smaller periodicities such as ripples and smaller dunes and that the proposed methodology effectively discriminates waves of different periods for Nyquist ratios higher than 25 and signal-to-noise ratios higher than 5. The analysis of bed forms in the Río Paraná reveals that, in most cases, a Gamma probability distribution, with a positive skewness, best describes the dimensionless wavelength and amplitude for both the lee and stoss sides of large dunes. For the case of smaller superimposed dunes, the dimensionless wavelength shows a discrete behavior that is governed by the sampling frequency of the data, and the dimensionless amplitude better fits the Gamma probability distribution, again with a positive skewness. This paper thus provides a robust methodology for systematically identifying the scales and magnitudes of bed forms in a range of environments.

A single promoter inversion switches Photorhabdus between pathogenic and mutualistic states.

PubMed

Somvanshi, Vishal S; Sloup, Rudolph E; Crawford, Jason M; Martin, Alexander R; Heidt, Anthony J; Kim, Kwi-suk; Clardy, Jon; Ciche, Todd A

2012-07-06

Microbial populations stochastically generate variants with strikingly different properties, such as virulence or avirulence and antibiotic tolerance or sensitivity. Photorhabdus luminescens bacteria have a variable life history in which they alternate between pathogens to a wide variety of insects and mutualists to their specific host nematodes. Here, we show that the P. luminescens pathogenic variant (P form) switches to a smaller-cell variant (M form) to initiate mutualism in host nematode intestines. A stochastic promoter inversion causes the switch between the two distinct forms. M-form cells are much smaller (one-seventh the volume), slower growing, and less bioluminescent than P-form cells; they are also avirulent and produce fewer secondary metabolites. Observations of form switching by individual cells in nematodes revealed that the M form persisted in maternal nematode intestines, were the first cells to colonize infective juvenile (IJ) offspring, and then switched to P form in the IJ intestine, which armed these nematodes for the next cycle of insect infection.

Droplet Breakup Mechanisms in Air-blast Atomizers

NASA Astrophysics Data System (ADS)

Aliabadi, Amir Abbas; Taghavi, Seyed Mohammad; Lim, Kelly

2011-11-01

Atomization processes are encountered in many natural and man-made phenomena. Examples are pollen release by plants, human cough or sneeze, engine fuel injectors, spray paint and many more. The physics governing the atomization of liquids is important in understanding and utilizing atomization processes in both natural and industrial processes. We have observed the governing physics of droplet breakup in an air-blast water atomizer using a high magnification, high speed, and high resolution LASER imaging technique. The droplet breakup mechanisms are investigated in three major categories. First, the liquid drops are flattened to form an oblate ellipsoid (lenticular deformation). Subsequent deformation depends on the magnitude of the internal forces relative to external forces. The ellipsoid is converted into a torus that becomes stretched and disintegrates into smaller drops. Second, the drops become elongated to form a long cylindrical thread or ligament that break up into smaller drops (Cigar-shaped deformation). Third, local deformation on the drop surface creates bulges and protuberances that eventually detach themselves from the parent drop to form smaller drops.

Hadronic light-by-light contribution to the muon g — 2

NASA Astrophysics Data System (ADS)

Guevara, Adolfo

2016-10-01

We have computed the hadronic light-by-light (LbL) contribution to the muon anomalous magnetic moment aμ in the frame of Chiral Perturbation Theory with the inclusion of the lightest resonance multiplets as dynamical fields (RχT). It is essential to give a more accurate prediction of this hadronic contribution due to the future projects of J-Parc and FNAL on reducing the uncertainty in this observable. We, therefore, computed the pseudoscalar transition form factor and proposed the measurement of the e+ e - →μ+ μ- π0 cross section and dimuon invariant mass spectrum to determine more accurately its parameters. Then, we evaluated the pion exchange contribution to αμ, obtaining (6.66 ± 0.21) • 10-10. By comparing the pion exchange contribution and the pion-pole approximation to the corresponding transition form factor (πTFF) we recalled that the latter underestimates the complete πTFF by (15-20)%. Then, we obtained the η(') TFF, obtaining a total contribution of the lightest pseudoscalar exchanges of (10.47 ± 0.54) • 10-10, in agreement with previous results and with smaller error.

Analysis of interstellar cloud structure based on IRAS images

NASA Technical Reports Server (NTRS)

Scalo, John M.

1992-01-01

The goal of this project was to develop new tools for the analysis of the structure of densely sampled maps of interstellar star-forming regions. A particular emphasis was on the recognition and characterization of nested hierarchical structure and fractal irregularity, and their relation to the level of star formation activity. The panoramic IRAS images provided data with the required range in spatial scale, greater than a factor of 100, and in column density, greater than a factor of 50. In order to construct densely sampled column density maps of star-forming clouds, column density images of four nearby cloud complexes were constructed from IRAS data. The regions have various degrees of star formation activity, and most of them have probably not been affected much by the disruptive effects of young massive stars. The largest region, the Scorpius-Ophiuchus cloud complex, covers about 1000 square degrees (it was subdivided into a few smaller regions for analysis). Much of the work during the early part of the project focused on an 80 square degree region in the core of the Taurus complex, a well-studied region of low-mass star formation.

Role of carbohydrate in multimeric structure of factor VIII/von Willebrand factor protein.

PubMed Central

Gralnick, H R; Williams, S B; Rick, M E

1983-01-01

The carbohydrate moiety of the factor VIII/von Willebrand (vW) factor protein is important in the expression of vW factor activity and the intravascular survival of the protein. Studies of normal human factor VIII/vW factor protein indicate that there is a requirement of a full complement of penultimate galactose for the maintenance of a normal multimeric structure. Release of penultimate galactose by beta-galactosidase or modification by galactose oxidase results in loss of the largest molecular weight multimers and increased numbers of intermediate and smaller multimers. In contrast, terminal galactose on the factor VIII/vW factor protein does not appear to play a significant role in the maintenance of the multimer organization. The abnormalities in multimeric structure and molecular size were demonstrated by NaDodSO4/polyacrylamide/agarose gel electrophoresis, NaDodSO4/glyoxyl-agarose electrophoresis, and sucrose density ultracentrifugation. These studies indicate that the penultimate galactose plays a role in the maintenance of the largest multimers of the factor VIII/vW factor protein. This may explain why, in some patients with variant forms of vW disease, a carbohydrate abnormality also may affect the multimeric structure of the plasma factor VIII/vW factor protein. Images PMID:6601805

Large woody debris and flow resistance in step-pool channels, Cascade Range, Washington

USGS Publications Warehouse

Curran, Janet H.; Wohl, Ellen E.

2003-01-01

Total flow resistance, measured as Darcy-Weisbach f, in 20 step-pool channels with large woody debris (LWD) in Washington, ranged from 5 to 380 during summer low flows. Step risers in the study streams consist of either (1) large and relatively immobile woody debris, bedrock, or roots that form fixed, or “forced,” steps, or (2) smaller and relatively mobile wood or clasts, or a mixture of both, arranged across the channel by the stream. Flow resistance in step-pool channels may be partitioned into grain, form, and spill resistance. Grain resistance is calculated as a function of particle size, and form resistance is calculated as large woody debris drag. Combined, grain and form resistance account for less than 10% of the total flow resistance. We initially assumed that the substantial remaining portion is spill resistance attributable to steps. However, measured step characteristics could not explain between-reach variations in flow resistance. This suggests that other factors may be significant; the coefficient of variation of the hydraulic radius explained 43% of the variation in friction factors between streams, for example. Large woody debris generates form resistance on step treads and spill resistance at step risers. Because the form resistance of step-pool channels is relatively minor compared to spill resistance and because wood in steps accentuates spill resistance by increasing step height, we suggest that wood in step risers influences channel hydraulics more than wood elsewhere in the channel. Hence, the distribution and function, not just abundance, of large woody debris is critical in steep, step-pool channels.

Mammal extinctions, body size, and paleotemperature

USGS Publications Warehouse

Bown, T.M.; Holroyd, P.A.; Rose, K.D.

1994-01-01

There is a general inverse relationship between the natural logarithm of tooth area (a body size indicator) of some fossil mammals and paleotemperature during approximately 2.9 million years of the early Eocene in the Bighorn Basin of northwest Wyoming. When mean temperatures became warmer, tooth areas tended to become smaller. During colder times, larger species predominated; these generally became larger or remained the same size. Paleotemperature trends also markedly affected patterns of local (and, perhaps, regional) extinction and immigration. New species appeared as immigrants during or near the hottest (smaller forms) and coldest (larger forms) intervals. Paleotemperature trend reversals commonly resulted in the ultimate extinction of both small forms (during cooling intervals) and larger forms (during warming intervals). These immigrations and extinctions mark faunal turnovers that were also modulated by sharp increases in sediment accumulation rate.

The effect of visual-motion time-delays on pilot performance in a simulated pursuit tracking task

NASA Technical Reports Server (NTRS)

Miller, G. K., Jr.; Riley, D. R.

1977-01-01

An experimental study was made to determine the effect on pilot performance of time delays in the visual and motion feedback loops of a simulated pursuit tracking task. Three major interrelated factors were identified: task difficulty either in the form of airplane handling qualities or target frequency, the amount and type of motion cues, and time delay itself. In general, the greater the task difficulty, the smaller the time delay that could exist without degrading pilot performance. Conversely, the greater the motion fidelity, the greater the time delay that could be tolerated. The effect of motion was, however, pilot dependent.

Ultrastructure and growth factor content of equine platelet-rich fibrin gels.

PubMed

Textor, Jamie A; Murphy, Kaitlin C; Leach, J Kent; Tablin, Fern

2014-04-01

To compare fiber diameter, pore area, compressive stiffness, gelation properties, and selected growth factor content of platelet-rich fibrin gels (PRFGs) and conventional fibrin gels (FGs). PRFGs and conventional FGs prepared from the blood of 10 healthy horses. Autologous fibrinogen was used to form conventional FGs. The PRFGs were formed from autologous platelet-rich plasma of various platelet concentrations (100 × 10³ platelets/μL, 250 × 10³ platelets/μL, 500 × 10³ platelets/μL, and 1,000 × 10³ platelets/μL). All gels contained an identical fibrinogen concentration (20 mg/mL). Fiber diameter and pore area were evaluated with scanning electron microscopy. Maximum gelation rate was assessed with spectrophotometry, and gel stiffness was determined by measuring the compressive modulus. Gel weights were measured serially over 14 days as an index of contraction (volume loss). Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were quantified with ELISAs. Fiber diameters were significantly larger and mean pore areas were significantly smaller in PRFGs than in conventional FGs. Gel weight decreased significantly over time, differed significantly between PRFGs and conventional FGs, and was significantly correlated with platelet concentration. Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were highest in gels and releasates derived from 1,000 × 10³ platelets/μL. The inclusion of platelets in FGs altered the architecture and increased the growth factor content of the resulting scaffold. Platelets may represent a useful means of modifying these gels for applications in veterinary and human regenerative medicine.

Craters on Crater

NASA Image and Video Library

2006-10-10

Several craters were formed on the rim of this large crater. The movement of material downhill toward the floor of the large crater has formed interesting patterns on the floors of the smaller craters

Factors associated with lease financing in the hospital industry.

PubMed

McCue, Michael J

2007-01-01

In contrast to capital leases, which are reported on the balance sheet as debt, operating leases are a form of off-balance sheet financing only reported in the notes to the financial statement and have limited disclosure requirements. Following the perpetuity method of corporate finance, this study developed a capitalized operating lease value for hospitals. Evaluating the substitutability between lease and debt financing, the findings show a marginal displacement of debt by lease financing. Assessing the relationship of market, mission, operating, and financial factors on lease financing for all short-term, acute-care hospitals across the United States, the results indicate that investor-owned hospital management companies and hospitals located in CON markets are less likely to lease and that smaller hospitals with fewer unoccupied beds, higher proportion of government payers, low liquidity, and lower capital expenditures are more likely to lease.

Improved lattice computation of proton decay matrix elements

NASA Astrophysics Data System (ADS)

Aoki, Yasumichi; Izubuchi, Taku; Shintani, Eigo; Soni, Amarjit

2017-07-01

We present an improved result for the lattice computation of the proton decay matrix elements in Nf=2 +1 QCD. In this study, by adopting the error reduction technique of all-mode-averaging, a significant improvement of the statistical accuracy is achieved for the relevant form factor of proton (and also neutron) decay on the gauge ensemble of Nf=2 +1 domain-wall fermions with mπ=0.34 - 0.69 GeV on a 2.7 fm3 lattice, as used in our previous work [1]. We improve the total accuracy of matrix elements to 10-15% from 30-40% for p →π e+ or from 20-40% for p →K ν ¯. The accuracy of the low-energy constants α and β in the leading-order baryon chiral perturbation theory (BChPT) of proton decay are also improved. The relevant form factors of p →π estimated through the "direct" lattice calculation from the three-point function appear to be 1.4 times smaller than those from the "indirect" method using BChPT with α and β . It turns out that the utilization of our result will provide a factor 2-3 larger proton partial lifetime than that obtained using BChPT. We also discuss the use of these parameters in a dark matter model.

Effect of argon implantation on solid-state dewetting: control of size and surface density of silicon nanocrystals.

PubMed

Almadori, Y; Borowik, Ł; Chevalier, N; Barbé, J-C

2017-01-27

Thermally induced solid-state dewetting of ultra-thin films on insulators is a process of prime interest, since it is capable of easily forming nanocrystals. If no particular treatment is performed to the film prior to the solid-state dewetting, it is already known that the size, the shape and the density of nanocrystals is governed by the initial film thickness. In this paper, we report a novel approach to control the size and the surface density of silicon nanocrystals based on an argon-implantation preliminary surface treatment. Using 7.5 nm thin layers of silicon, we show that increasing the implantation dose tends to form smaller silicon nanocrystals with diameter and height lower than 50 nm and 30 nm, respectively. Concomitantly, the surface density is increased by a factor greater than 20, going from 5 μm -2 to values over 100 μm -2 .

On stars, galaxies and black holes in massive bigravity

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

Enander, Jonas; Mörtsell, Edvard, E-mail: enander@fysik.su.se, E-mail: edvard@fysik.su.se

In this paper we study the phenomenology of stars and galaxies in massive bigravity. We give parameter conditions for the existence of viable star solutions when the radius of the star is much smaller than the Compton wavelength of the graviton. If these parameter conditions are not met, we constrain the ratio between the coupling constants of the two metrics, in order to give viable conditions for e.g. neutron stars. For galaxies, we put constraints on both the Compton wavelength of the graviton and the conformal factor and coupling constants of the two metrics. The relationship between black holes andmore » stars, and whether the former can be formed from the latter, is discussed. We argue that the different asymptotic structure of stars and black holes makes it unlikely that black holes form from the gravitational collapse of stars in massive bigravity.« less

Landscape analysis: Theoretical considerations and practical needs

USGS Publications Warehouse

Godfrey, A.E.; Cleaves, E.T.

1991-01-01

Numerous systems of land classification have been proposed. Most have led directly to or have been driven by an author's philosophy of earth-forming processes. However, the practical need of classifying land for planning and management purposes requires that a system lead to predictions of the results of management activities. We propose a landscape classification system composed of 11 units, from realm (a continental mass) to feature (a splash impression). The classification concerns physical aspects rather than economic or social factors; and aims to merge land inventory with dynamic processes. Landscape units are organized using a hierarchical system so that information may be assembled and communicated at different levels of scale and abstraction. Our classification uses a geomorphic systems approach that emphasizes the geologic-geomorphic attributes of the units. Realm, major division, province, and section are formulated by subdividing large units into smaller ones. For the larger units we have followed Fenneman's delineations, which are well established in the North American literature. Areas and districts are aggregated into regions and regions into sections. Units smaller than areas have, in practice, been subdivided into zones and smaller units if required. We developed the theoretical framework embodied in this classification from practical applications aimed at land use planning and land management in Maryland (eastern Piedmont Province near Baltimore) and Utah (eastern Uinta Mountains). ?? 1991 Springer-Verlag New York Inc.

Morphological explanation of high tear resistance of EPDM/NR rubber blends.

PubMed

Gögelein, Christoph; Beelen, Henri Jacob Hubert; van Duin, Martin

2017-06-14

The fatigue properties of cross-linked blends of ethylene propylene diene rubber (EPDM) with low natural rubber (NR) content and reinforced with carbon black (CB) are studied. It is found that such EPDM/NR compounds have superior crack growth resistance and fatigue lifetime. For low NR contents, transmission electron microscopy reveals that the NR phase forms small droplets of 20-50 nm. Remarkably, these droplets are even smaller than the primary CB particles. Atomic force microscopy shows that the the NR phase droplets have a higher loss factor and a smaller elastic modulus than the surrounding EPDM matrix. Rheometer measurements are used to study the effect of the phase morphology on the rubber mechanical properties. These rheological data are compared with the prediction of the Eshelby model describing the effect of elastic inclusions on solids. A complex interplay between the rubber phase morphology and the solubility of both the sulfur cross-linking system and CB is observed, which cannot be predicted theoretically. It is proposed that the soft NR droplets effectively inhibit the crack propagation in the EPDM matrix.

Dynamics of Water Associated with Lithium Ions Distributed in Polyethylene Oxide

DOE PAGES

Zhang, Zhe; Ohl, Michael; Diallo, Souleymane O.; ...

2015-11-03

We studied the dynamics of water in polyethylene oxide (PEO)/LiCl solution with quasielastic neutron scattering experiments and molecular dynamics (MD) simulations. Two different time scales of water diffusion representing interfacial water and bulk water dynamics have been identified. Furthermore, the measured diffusion coefficient of interfacial water remained 5–10 times smaller than that of bulk water, but both were slowed by approximately 50% in the presence of Li +. Detailed analysis of MD trajectories suggests that Li + is favorably found at the surface of the hydration layer, and the probability to find the caged Li + configuration formed by themore » PEO is lower than for the noncaged Li +-PEO configuration. In both configurations, however, the slowing down of water molecules is driven by reorienting water molecules and creating water-Li + hydration complexes. Moreover, performing the MD simulation with different ions (Na + and K +) revealed that smaller ionic radius of the ions is a key factor in disrupting the formation of PEO cages by allowing spaces for water molecules to come in between the ion and PEO.« less

Dynamics of Water Associated with Lithium Ions Distributed in Polyethylene Oxide

NASA Astrophysics Data System (ADS)

Zhang, Zhe; Ohl, Michael; Diallo, Souleymane O.; Jalarvo, Niina H.; Hong, Kunlun; Han, Youngkyu; Smith, Gregory S.; Do, Changwoo

2015-11-01

The dynamics of water in polyethylene oxide (PEO)/LiCl solution has been studied with quasielastic neutron scattering experiments and molecular dynamics (MD) simulations. Two different time scales of water diffusion representing interfacial water and bulk water dynamics have been identified. The measured diffusion coefficient of interfacial water remained 5-10 times smaller than that of bulk water, but both were slowed by approximately 50% in the presence of Li+ . Detailed analysis of MD trajectories suggests that Li+ is favorably found at the surface of the hydration layer, and the probability to find the caged Li+ configuration formed by the PEO is lower than for the noncaged Li+-PEO configuration. In both configurations, however, the slowing down of water molecules is driven by reorienting water molecules and creating water-Li+ hydration complexes. Performing the MD simulation with different ions (Na+ and K+ ) revealed that smaller ionic radius of the ions is a key factor in disrupting the formation of PEO cages by allowing spaces for water molecules to come in between the ion and PEO.

Dynamics of Water Associated with Lithium Ions Distributed in Polyethylene Oxide.

PubMed

Zhang, Zhe; Ohl, Michael; Diallo, Souleymane O; Jalarvo, Niina H; Hong, Kunlun; Han, Youngkyu; Smith, Gregory S; Do, Changwoo

2015-11-06

The dynamics of water in polyethylene oxide (PEO)/LiCl solution has been studied with quasielastic neutron scattering experiments and molecular dynamics (MD) simulations. Two different time scales of water diffusion representing interfacial water and bulk water dynamics have been identified. The measured diffusion coefficient of interfacial water remained 5-10 times smaller than that of bulk water, but both were slowed by approximately 50% in the presence of Li(+). Detailed analysis of MD trajectories suggests that Li(+) is favorably found at the surface of the hydration layer, and the probability to find the caged Li(+) configuration formed by the PEO is lower than for the noncaged Li(+)-PEO configuration. In both configurations, however, the slowing down of water molecules is driven by reorienting water molecules and creating water-Li(+) hydration complexes. Performing the MD simulation with different ions (Na(+) and K(+)) revealed that smaller ionic radius of the ions is a key factor in disrupting the formation of PEO cages by allowing spaces for water molecules to come in between the ion and PEO.

A Comparative Analysis of Barchan Dunes in the Intra-Crater Dune Fields and the North Polar Sand Sea

NASA Astrophysics Data System (ADS)

Bourke, M. C.; Balme, M.; Zimbelman, J.

2004-03-01

Contrasting wind, sediment and frost precipitation regimes contribute to different dune scale and form on Mars. Isolated barchans in the NPSS are smaller but assume a classic barchan form. Intra-crater barchans are larger and more variable in form.

Implementation of an integrating sphere for the enhancement of noninvasive glucose detection using quantum cascade laser spectroscopy

NASA Astrophysics Data System (ADS)

Werth, Alexandra; Liakat, Sabbir; Dong, Anqi; Woods, Callie M.; Gmachl, Claire F.

2018-05-01

An integrating sphere is used to enhance the collection of backscattered light in a noninvasive glucose sensor based on quantum cascade laser spectroscopy. The sphere enhances signal stability by roughly an order of magnitude, allowing us to use a thermoelectrically (TE) cooled detector while maintaining comparable glucose prediction accuracy levels. Using a smaller TE-cooled detector reduces form factor, creating a mobile sensor. Principal component analysis has predicted principal components of spectra taken from human subjects that closely match the absorption peaks of glucose. These principal components are used as regressors in a linear regression algorithm to make glucose concentration predictions, over 75% of which are clinically accurate.

Imaging and Screening of Cancer of the Gallbladder and Bile Ducts.

PubMed

Sandrasegaran, Kumar; Menias, Christine O

2017-11-01

Biliary cancers include gallbladder cancer (GBC) and cholangiocarcinoma (CCA). GBC may appear as a mass replacing the gallbladder, thickened gallbladder wall, or polypoid lesion in the gallbladder. Gallbladder polyps with low risk of GBC (eg, 6- to 10-mm polyps without other risk factors) are screened with sonography. In general, polyps smaller than 5 mm are ignored and those larger than 10 mm require surgical consideration. Screening for CCA is less well-established. On imaging, CCA may be divided into mass-forming, periductal infiltrating, and intraductal types. This review discusses the current state of screening and diagnosis of GBC and CCA. Copyright © 2017 Elsevier Inc. All rights reserved.

Synchronization behaviors of coupled neurons under electromagnetic radiation

NASA Astrophysics Data System (ADS)

Ma, Jun; Wu, Fuqiang; Wang, Chunni

2017-01-01

Based on an improved neuronal model, in which the effect of magnetic flux is considered during the fluctuation and change of ion concentration in cells, the transition of synchronization is investigated by imposing external electromagnetic radiation on the coupled neurons, and networks, respectively. It is found that the synchronization degree depends on the coupling intensity and the intensity of external electromagnetic radiation. Indeed, appropriate intensity of electromagnetic radiation could be effective to realize intermittent synchronization, while stronger intensity of electromagnetic radiation can induce disorder of coupled neurons and network. Neurons show rhythm synchronization in the electrical activities by increasing the coupling intensity under electromagnetic radiation, and spatial patterns can be formed in the network under smaller factor of synchronization.

Methodology for sensitivity analysis, approximate analysis, and design optimization in CFD for multidisciplinary applications

NASA Technical Reports Server (NTRS)

Taylor, Arthur C., III; Hou, Gene W.

1993-01-01

In this study involving advanced fluid flow codes, an incremental iterative formulation (also known as the delta or correction form) together with the well-known spatially-split approximate factorization algorithm, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For smaller 2D problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. Iterative methods are needed for larger 2D and future 3D applications, however, because direct methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioning of the coefficient matrix; this problem can be overcome when these equations are cast in the incremental form. These and other benefits are discussed. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two sample airfoil problems: (1) subsonic low Reynolds number laminar flow; and (2) transonic high Reynolds number turbulent flow.

Evolution and genetics of root hair stripes in the root epidermis.

PubMed

Dolan, L; Costa, S

2001-03-01

Root hair pattern develops in a number of different ways in angiosperm. Cells in the epidermis of some species undergo asymmetric cell divisions to form a smaller daughter cell from which a hair grows, and a larger cell that forms a non-hair epidermal cell. In other species any cell in the epidermis can form a root hair. Hair cells are arranged in files along the Arabidopsis root, located in the gaps between underlying cortical cell files. Epidermal cells overlying a single cortical cell file develop as non-hair epidermal cells. Genetic analysis has identified a transcription factor cascade required for the formation of this pattern. WEREWOLF (WER) and GLABRA2 (GL2) are required for the formation of non-hair epidermal cells while CAPRICE (CPC) is required for hair cell development. Recent analyses of the pattern of epidermal cells among the angiosperms indicate that this striped pattern of cell organization evolved from non-striped ancestors independently in a number of diverse evolutionary lineages. The genetic basis for the evolution of epidermal pattern in angiosperms may now be examined.

Dust ring formation due to sublimation of dust grains drifting radially inward by the Poynting-Robertson drag: An analytical model

NASA Astrophysics Data System (ADS)

Kobayashi, Hiroshi; Watanabe, Sei-ichiro; Kimura, Hiroshi; Yamamoto, Tetsuo

2009-05-01

Dust particles exposed to the stellar radiation and wind drift radially inward by the Poynting-Robertson (P-R) drag and pile up at the zone where they begin to sublime substantially. The reason they pile up or form a ring is that their inward drifts due to the P-R drag are suppressed by stellar radiation pressure when the ratio of radiation pressure to stellar gravity on them increases during their sublimation phases. We present analytic solutions to the orbital and mass evolution of such subliming dust particles, and find their drift velocities at the pileup zone are almost independent of their initial semimajor axes and masses. We derive analytically an enhancement factor of the number density of the particles at the outer edge of the sublimation zone from the solutions. We show that the formula of the enhancement factor reproduces well numerical simulations in the previous studies. The enhancement factor for spherical dust particles of silicate and carbon extends from 3 to more than 20 at stellar luminosities L=0.8-500L, where L is solar luminosity. Although the enhancement factor for fluffy dust particles is smaller than that for spherical particles, sublimating particles inevitably form a dust ring as long as their masses decrease faster than their surface areas during sublimation. The formulation is applicable to dust ring formation for arbitrary shape and material of dust in dust-debris disks as well as in the Solar System.

Factors that affect coseismic folds in an overburden layer

NASA Astrophysics Data System (ADS)

Zeng, Shaogang; Cai, Yongen

2018-03-01

Coseismic folds induced by blind thrust faults have been observed in many earthquake zones, and they have received widespread attention from geologists and geophysicists. Numerous studies have been conducted regarding fold kinematics; however, few have studied fold dynamics quantitatively. In this paper, we establish a conceptual model with a thrust fault zone and tectonic stress load to study the factors that affect coseismic folds and their formation mechanisms using the finite element method. The numerical results show that the fault dip angle is a key factor that controls folding. The greater the dip angle is, the steeper the fold slope. The second most important factor is the overburden thickness. The thicker the overburden is, the more gradual the fold. In this case, folds are difficult to identify in field surveys. Therefore, if a fold can be easily identified with the naked eye, the overburden is likely shallow. The least important factors are the mechanical parameters of the overburden. The larger the Young's modulus of the overburden is, the smaller the displacement of the fold and the fold slope. Strong horizontal compression and vertical extension in the overburden near the fault zone are the main mechanisms that form coseismic folds.

Unraveling the Pore-Forming Steps of Pneumolysin from Streptococcus pneumoniae.

PubMed

van Pee, Katharina; Mulvihill, Estefania; Müller, Daniel J; Yildiz, Özkan

2016-12-14

Pneumolysin (PLY) is the main virulence factor of Streptococcus pneumoniae that causes pneumonia, meningitis, and invasive pneumococcal infection. PLY is produced as monomers, which bind to cholesterol-containing membranes, where they oligomerize into large pores. To investigate the pore-forming mechanism, we determined the crystal structure of PLY at 2.4 Å and used it to design mutants on the surface of monomers. Electron microscopy of liposomes incubated with PLY mutants revealed that several mutations interfered with ring formation. Mutants that formed incomplete rings or linear arrays had strongly reduced hemolytic activity. By high-resolution time-lapse atomic force microscopy of wild-type PLY, we observed two different ring-shaped complexes. Most of the complexes protruded ∼8 nm above the membrane surface, while a smaller number protruded ∼11 nm or more. The lower complexes were identified as pores or prepores by the presence or absence of a lipid bilayer in their center. The taller complexes were side-by-side assemblies of monomers of soluble PLY that represent an early form of the prepore. Our observations suggest a four-step mechanism of membrane attachment and pore formation by PLY, which is discussed in the context of recent structural models. The functional separation of these steps is necessary for the understanding how cholesterol-dependent cytolysins form pores and lyse cells.

Nano-fabricated plasmonic optical transformer

DOEpatents

Choo, Hyuck; Cabrini, Stefano; Schuck, P. James; Liang, Xiaogan; Yablonovitch, Eli

2015-06-09

The present invention provides a plasmonic optical transformer to produce a highly focuses optical beam spot, where the transformer includes a first metal layer, a dielectric layer formed on the first metal layer, and a second metal layer formed on the dielectric layer, where the first metal layer, the dielectric layer, and the second layer are patterned to a shape including a first section having a first cross section, a second section following the first section having a cross-section tapering from the first section to a smaller cross-section, and a third section following the second section having a cross-section matching the tapered smaller cross-section of the second section.

Memory and Spin Injection Devices Involving Half Metals

DOE PAGES

Shaughnessy, M.; Snow, Ryan; Damewood, L.; ...

2011-01-01

We suggest memory and spin injection devices fabricated with half-metallic materials and based on the anomalous Hall effect. Schematic diagrams of the memory chips, in thin film and bulk crystal form, are presented. Spin injection devices made in thin film form are also suggested. These devices do not need any external magnetic field but make use of their own magnetization. Only a gate voltage is needed. The carriers are 100% spin polarized. Memory devices may potentially be smaller, faster, and less volatile than existing ones, and the injection devices may be much smaller and more efficient than existing spin injectionmore » devices.« less

Improved lattice computation of proton decay matrix elements

DOE PAGES

Aoki, Yasumichi; Izubuchi, Taku; Shintani, Eigo; ...

2017-07-14

In this paper, we present an improved result for the lattice computation of the proton decay matrix elements in N f = 2 + 1 QCD. In this study, by adopting the error reduction technique of all-mode-averaging, a significant improvement of the statistical accuracy is achieved for the relevant form factor of proton (and also neutron) decay on the gauge ensemble of N f= 2 + 1 domain-wall fermions with m π = 0.34 – 0.69 GeV on a 2.7 fm 3 lattice, as used in our previous work. We improve the total accuracy of matrix elements to 10–15% from 30–40% for p → πe + or from 20–40% for p → Kmore » $$\\bar{ν}$$. The accuracy of the low-energy constants α and β in the leading-order baryon chiral perturbation theory (BChPT) of proton decay are also improved. The relevant form factors of p → π estimated through the “direct” lattice calculation from the three-point function appear to be 1.4 times smaller than those from the “indirect” method using BChPT with α and β . It turns out that the utilization of our result will provide a factor 2–3 larger proton partial lifetime than that obtained using BChPT. Lastly, we also discuss the use of these parameters in a dark matter model.« less

Differences in risk factors for retinopathy of prematurity development in paired twins: a Chinese population study.

PubMed

Yau, Gordon S K; Lee, Jacky W Y; Tam, Victor T Y; Yip, Stan; Cheng, Edith; Liu, Catherine C L; Chu, Benjamin C Y; Yuen, Can Y F

2014-01-01

To determine the differences in risk factors for retinopathy of prematurity (ROP) in paired twins. A retrospective medical record review was performed for all paired twins screened for ROP between 2007 and 2012. Screening was offered to very low birth weight (≤ 1500 grams) and preterm (≤ 32 weeks) neonates. Twins 1 and 2 were categorized based on the order of delivery. Maternal and neonatal covariates were analyzed using univariate and multivariate regression analyses for both ROP and Type 1 ROP. In 34 pairs of Chinese twins, the mean gestational age (GA) was 30.2 ± 2.0 weeks. In Twin 1, smaller GA (OR = 0.44, P = 0.02), higher mean oxygen concentration (OR = 1.34, P = 0.03), presence of thrombocytopenia (OR = 1429.60, P < 0.0001), and intraventricular hemorrhage (OR = 18.67, P = 0.03) were significant risk factors for ROP. For Twin 2, a smaller GA (OR = 0.45, P = 0.03) was the only risk factor. There were no significant risk factors for ROP in Twin 1 or Twin 2 on multivariate analysis. In Chinese twin pairs, smaller GA was the only common risk factor for ROP while Twin 1 was more susceptible to the postnatal risks for ROP.

Manipulation of P-TEFb control machinery by HIV: recruitment of P-TEFb from the large form by Tat and binding of HEXIM1 to TAR

PubMed Central

Sedore, Stanley C.; Byers, Sarah A.; Biglione, Sebastian; Price, Jason P.; Maury, Wendy J.; Price, David H.

2007-01-01

Basal transcription of the HIV LTR is highly repressed and requires Tat to recruit the positive transcription elongation factor, P-TEFb, which functions to promote the transition of RNA polymerase II from abortive to productive elongation. P-TEFb is found in two forms in cells, a free, active form and a large, inactive complex that also contains 7SK RNA and HEXIM1 or HEXIM2. Here we show that HIV infection of cells led to the release of P-TEFb from the large form. Consistent with Tat being the cause of this effect, transfection of a FLAG-tagged Tat in 293T cells caused a dramatic shift of P-TEFb out of the large form to a smaller form containing Tat. In vitro, Tat competed with HEXIM1 for binding to 7SK, blocked the formation of the P-TEFb–HEXIM1–7SK complex, and caused the release P-TEFb from a pre-formed P-TEFb–HEXIM1–7SK complex. These findings indicate that Tat can acquire P-TEFb from the large form. In addition, we found that HEXIM1 binds tightly to the HIV 5′ UTR containing TAR and recruits and inhibits P-TEFb activity. This suggests that in the absence of Tat, HEXIM1 may bind to TAR and repress transcription elongation of the HIV LTR. PMID:17576689

Negative dysphotopsia: Causes and rationale for prevention and treatment.

PubMed

Holladay, Jack T; Simpson, Michael J

2017-02-01

To determine the cause of negative dysphotopsia using standard ray-tracing techniques and identify the primary and secondary causative factors. Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. Experimental study. Zemax ray-tracing software was used to evaluate pseudophakic and phakic eye models to show the location of retinal field images from various visual field objects. Phakic retinal field angles (RFAs) were used as a reference for the perceived field locations for retinal images in pseudophakic eyes. In a nominal acrylic pseudophakic eye model with a 2.5 mm diameter pupil, the maximum RFA from rays refracted by the intraocular lens (IOL) was 85.7 degrees and the minimum RFA for rays missing the optic of the IOL was 88.3 degrees, leaving a dark gap (shadow) of 2.6 degrees in the extreme temporal field. The width of the shadow was more prominent for a smaller pupil, a larger angle kappa, an equi-biconvex or plano-convex IOL shape, and a smaller axial distance from iris to IOL and with the anterior capsule overlying the nasal IOL. Secondary factors included IOL edge design, material, diameter, decentration, tilt, and aspheric surfaces. Standard ray-tracing techniques showed that a shadow is present when there is a gap between the retinal images formed by rays missing the optic of the IOL and rays refracted by the IOL. Primary and secondary factors independently affected the width and location of the gap (or overlap). The ray tracing also showed a constriction and double retinal imaging in the extreme temporal visual field. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Significance of abnormal serum binding of insulin-like growth factor II in the development of hypoglycemia in patients with non-islet-cell tumors

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

Daughaday, W.H.; Kapadia, M.

1989-09-01

The authors reported that serum and tumor from a hypoglycemic patient with a fibrosarcoma contained insulin-like growth factor II (IGF-II), mostly in a large molecular form designated big IGF-II. They now describe two additional patients with non-islet-cell tumor with hypoglycemia (NICTH) whose sera contained big IGF-II. Removal of the tumor eliminated most of the big IGF-II from the sera of two patients. Because specific IGF-binding proteins modify the bioactivity of IGFs, the sizes of the endogenous IGF-binding protein complexes were determined after neutral gel filtration through Sephadex G-200. Normally about 75% of IGFs are carried as a ternary complex ofmore » 150 kDa consisting of IGF, a growth hormone (GH)-dependent IGF-binding protein, and an acid-labile complexing component. The three patients with NICTH completely lacked the 150-kDa complex. IGF-II was present as a 60-kDa complex with variable contributions of smaller complexes. In the immediate postoperative period, a 110-kDa complex appeared rather than the expected 150-kDa complex. Abnormal IGF-II binding may be important in NICTH because the 150-kDa complexes cross the capillary membrane poorly. The smaller complexes present in our patients' sera would be expected to enter interstitial fluid readily, and a 4- to 5-fold increase in the fraction of IGFs reaching the target cells would result.« less

Organizational resilience: Sustained institutional effectiveness among smaller, private, non-profit US higher education institutions experiencing organizational decline.

PubMed

Moran, Kenneth A

2016-06-04

Recent changes in the United States (US) economy have radically disrupted revenue generation among many institutions within higher education within the US. Chief among these disruptions has been fallout associated with the financial crisis of 2008-2009, which triggered a change in the US higher education environment from a period of relative munificence to a prolonged period of scarcity. The hardest hit by this disruption have been smaller, less wealthy institutions which tend to lack the necessary reserves to financially weather the economic storm. Interestingly, a review of institutional effectiveness among these institutions revealed that while many are struggling, some institutions have found ways to not only successfully cope with the impact of declining revenue, but have been able to capitalize on the disruption and thrive. Organizational response is an important factor in successfully coping with conditions of organizational decline. The study examined the impacts of organizational response on institutional effectiveness among higher education institutions experiencing organizational decline. The study's research question asked why some US higher educational institutions are more resilient at coping with organizational decline than other institutions operating within the same segment of the higher education sector. More specifically, what role does organizational resilience have in helping smaller, private non-profit institutions cope and remain effective during organizational decline? A total of 141 US smaller, private non-profit higher educational institutions participated in the study; specifically, the study included responses from participant institutions' key administrators. 60-item survey evaluated administrator responses corresponding to organizational response and institutional effectiveness. Factor analysis was used to specify the underlying structures of rigidity response, resilience response, and institutional effectiveness. Multiple regression analysis was used to examine the direct and interaction effects between organizational decline, organizational rigidity response, organizational resilience response, and institutional effectiveness, controlling for age of institution and level of endowment. The study validated previous threat-rigidity response findings that organizational decline alone does not adversely impact institutional effectiveness. The direct effect of Goal-Directed Solution Seeking and Role Dependency organizational resilience factors had a positive, significant correlation with the Student Personal Development institutional effectiveness factor. The interactive effect of Goal-Directed Solution Seeking organizational resilience factor during organizational decline had a positive, significant correlation with the Professional Development and Quality of Faculty institutional effectiveness factor. The interactive effect of Avoidance during organizational decline had a positive, significant correlation with the Faculty and Administrator Employment Satisfaction institutional effectiveness factor. The interactive effect of Diminished Innovation, Morale, and Leader Credibility rigidity response factor and Avoidance organizational resilience factor during organizational decline had a positive, significant correlation with the Professional Development and Quality of Faculty institutional effectiveness factor. Lastly, the interactive effect of Increased Scapegoating of Leaders, Interest group Activities, and Conflict rigidity response factor and Avoidance organizational resilience factor during organizational decline had a positive, significant correlation with the Faculty and Administrator Employment Satisfaction institutional effectiveness factor. Factors of organizational resilience were found to have a positive effect among smaller, private non-profit higher educational institutions associated with this study toward sustaining institutional effectiveness during organizational decline. Specifically, the organizational resilience factors of Goal-Directed Solution Seeking (i.e., mission-driven solutions) and Avoidance (i.e., skepticism toward new ideas) play a significant, collaborative role among smaller, private non-profit higher educational institutions when it comes to sustaining institutional effectiveness during organizational decline.

The U.S.-Canada Border Effect : Smaller Than Previously Thought and Becoming Smaller

DOT National Transportation Integrated Search

2012-05-30

We revisit the effect of the U.S.-Canada national border on trade, considering to what extent the border reduces trade when : observable economic factors are controlled. A reexamination of the data yields estimates of the border effect that are 50% :...

Figure-ground assignment to a translating contour: a preference for advancing vs. receding motion.

PubMed

Barenholtz, Elan; Tarr, Michael J

2009-05-28

Past research on figure-ground assignment to contours has largely considered static stimuli. Here we report a simple and extremely robust dynamic cue to figural assignment, based on whether the bounding region of a contour is growing larger within the field of view ("advancing") rather than smaller ("receding"). Subjects viewed a straight or jagged contour dividing two colored regions translating behind a virtual aperture and had to report which color they had seen "moving in front", effectively assigning figure to that side of the contour. Across three experiments, subjects showed a strong preference to assign figure such that the bounded contour was advancing. This was true regardless of the direction of motion of the contour and regardless of the initial/ending size of the bounded regions (i.e., the motion cue served to override the conventional cue to figure-ground of smaller area). In a fourth, control experiment, subjects showed no such bias when it was the aperture, rather than the contour, that moved, demonstrating that the effect depends on contour motion and not simply an increase in area. We discuss a possible explanation for this bias as well as the general implications regarding dynamic factors in form perception.

Morphological classification of bioaerosols from composting using scanning electron microscopy

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

Tamer Vestlund, A.; FIRA International Ltd., Maxwell Road, Stevenage, Herts SG1 2EW; Al-Ashaab, R.

2014-07-15

Highlights: • Bioaerosols were captured using the filter method. • Bioaerosols were analysed using scanning electron microscope. • Bioaerosols were classified on the basis of morphology. • Single small cells were found more frequently than aggregates and larger cells. • Smaller cells may disperse further than heavier aggregate structures. - Abstract: This research classifies the physical morphology (form and structure) of bioaerosols emitted from open windrow composting. Aggregation state, shape and size of the particles captured are reported alongside the implications for bioaerosol dispersal after release. Bioaerosol sampling took place at a composting facility using personal air filter samplers. Samplesmore » were analysed using scanning electron microscopy. Particles were released mainly as small (<1 μm) single, spherical cells, followed by larger (>1 μm) single cells, with aggregates occurring in smaller proportions. Most aggregates consisted of clusters of 2–3 particles as opposed to chains, and were <10 μm in size. No cells were attached to soil debris or wood particles. These small single cells or small aggregates are more likely to disperse further downwind from source, and cell viability may be reduced due to increased exposure to environmental factors.« less

Geochemical Constraints on the Size of the Moon — Forming Giant Impact

NASA Astrophysics Data System (ADS)

Piet, H.; Badro, J.; Gillet, P.

2018-05-01

We use the partitioning of siderophile trace elements to model the geochemical influence of the Moon-forming giant impact on Earth’s mantle during core formation. We find the size of the impactor to be 15% of Earth mass or smaller.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension.

PubMed

Nieuwland, Mante S; Politzer-Ahles, Stephen; Heyselaar, Evelien; Segaert, Katrien; Darley, Emily; Kazanina, Nina; Von Grebmer Zu Wolfsthurn, Sarah; Bartolozzi, Federica; Kogan, Vita; Ito, Aine; Mézière, Diane; Barr, Dale J; Rousselet, Guillaume A; Ferguson, Heather J; Busch-Moreno, Simon; Fu, Xiao; Tuomainen, Jyrki; Kulakova, Eugenia; Husband, E Matthew; Donaldson, David I; Kohút, Zdenko; Rueschemeyer, Shirley-Ann; Huettig, Falk

2018-04-03

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment ('cloze'). In our direct replication study spanning 9 laboratories ( N =334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words. © 2018, Nieuwland et al.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension

PubMed Central

Politzer-Ahles, Stephen; Heyselaar, Evelien; Segaert, Katrien; Darley, Emily; Kazanina, Nina; Von Grebmer Zu Wolfsthurn, Sarah; Bartolozzi, Federica; Kogan, Vita; Ito, Aine; Mézière, Diane; Barr, Dale J; Rousselet, Guillaume A; Ferguson, Heather J; Busch-Moreno, Simon; Fu, Xiao; Tuomainen, Jyrki; Kulakova, Eugenia; Husband, E Matthew; Donaldson, David I; Kohút, Zdenko; Rueschemeyer, Shirley-Ann; Huettig, Falk

2018-01-01

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment (‘cloze’). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words. PMID:29631695

Dimer model for Tau proteins bound in microtubule bundles

NASA Astrophysics Data System (ADS)

Hall, Natalie; Kluber, Alexander; Hayre, N. Robert; Singh, Rajiv; Cox, Daniel

2013-03-01

The microtubule associated protein tau is important in nucleating and maintaining microtubule spacing and structure in neuronal axons. Modification of tau is implicated as a later stage process in Alzheimer's disease, but little is known about the structure of tau in microtubule bundles. We present preliminary work on a proposed model for tau dimers in microtubule bundles (dimers are the minimal units since there is one microtubule binding domain per tau). First, a model of tau monomer was created and its characteristics explored using implicit solvent molecular dynamics simulation. Multiple simulations yield a partially collapsed form with separate positively/negatively charged clumps, but which are a factor of two smaller than required by observed microtubule spacing. We argue that this will elongate in dimer form to lower electrostatic energy at a cost of entropic ``spring'' energy. We will present preliminary results on steered molecular dynamics runs on tau dimers to estimate the actual force constant. Supported by US NSF Grant DMR 1207624.

Physical barrier effect of geopolymeric waste form on diffusivity of cesium and strontium.

PubMed

Jang, J G; Park, S M; Lee, H K

2016-11-15

The present study investigates the physical barrier effect of geopolymeric waste form on leaching behavior of cesium and strontium. Fly ash-based geopolymers and slag-blended geopolymers were used as solidification agents. The leaching behavior of cesium and strontium from geopolymers was evaluated in accordance with ANSI/ANS-16.1. The diffusivity of cesium and strontium in a fly ash-based geopolymer was lower than that in Portland cement by a factor of 10(3) and 10(4), respectively, showing significantly improved immobilization performance. The leaching resistance of fly ash-based geopolymer was relatively constant regardless of the type of fly ash. The diffusivity of water-soluble cesium and strontium ions were highly correlated with the critical pore diameter of the binder. The critical pore diameter of the fly ash-based geopolymer was remarkably smaller than those of Portland cement and slag-blended geopolymer; consequently, its ability physically to retard the diffusion of nuclides (physical barrier effect) was superior. Copyright © 2016 Elsevier B.V. All rights reserved.

Self-Interaction Error in Density Functional Theory: An Appraisal.

PubMed

Bao, Junwei Lucas; Gagliardi, Laura; Truhlar, Donald G

2018-05-03

Self-interaction error (SIE) is considered to be one of the major sources of error in most approximate exchange-correlation functionals for Kohn-Sham density-functional theory (KS-DFT), and it is large with all local exchange-correlation functionals and with some hybrid functionals. In this work, we consider systems conventionally considered to be dominated by SIE. For these systems, we demonstrate that by using multiconfiguration pair-density functional theory (MC-PDFT), the error of a translated local density-functional approximation is significantly reduced (by a factor of 3) when using an MCSCF density and on-top density, as compared to using KS-DFT with the parent functional; the error in MC-PDFT with local on-top functionals is even lower than the error in some popular KS-DFT hybrid functionals. Density-functional theory, either in MC-PDFT form with local on-top functionals or in KS-DFT form with some functionals having 50% or more nonlocal exchange, has smaller errors for SIE-prone systems than does CASSCF, which has no SIE.

Use of cranial characters in taxonomy of the Minnesota wolf (Canis sp.)

USGS Publications Warehouse

Mech, L.D.; Nowak, R.M.; Weisberg, S.

2011-01-01

Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from southeastern Ontario and smaller than those of western wolves. However, Minnesota wolf skulls during 1970-1976 showed a shift to the larger, western form. Although Minnesota skull measurements after 1976 were unavailable, rostral ratios from 1969 through 1999 were consistent with hybridization between the smaller eastern wolf and the western form. Our findings help resolve the different taxonomic interpretations of Minnesota skull morphology and are consistent with molecular evidence of recent hybridization or intergradation of the two forms of wolves in Minnesota. Together these data indicate that eastern- and western-type wolves historically mixed and hybridized in Minnesota and continue to do so. Our findings are relevant to a recent government proposal to delist wolves from the endangered species list in Minnesota and surrounding states.

Use of cranial characters in taxonomy of the Minnesota wolf (Canis sp.)

USGS Publications Warehouse

Mech, L. David; Nowak, Ronald M.; Weisberg, Sanford

2011-01-01

Minnesota wolves (Canis sp.) sometimes are reported to have affinity to a small, narrow-skulled eastern form (Canis lupus lycaon Schreber, 1775) and sometimes to a larger, broader western form (Canis lupus nubilus Say, 1823). We found that pre-1950 Minnesota wolf skulls were similar in size to those of wolves from southeastern Ontario and smaller than those of western wolves. However, Minnesota wolf skulls during 1970–1976 showed a shift to the larger, western form. Although Minnesota skull measurements after 1976 were unavailable, rostral ratios from 1969 through 1999 were consistent with hybridization between the smaller eastern wolf and the western form. Our findings help resolve the different taxonomic interpretations of Minnesota skull morphology and are consistent with molecular evidence of recent hybridization or intergradation of the two forms of wolves in Minnesota. Together these data indicate that eastern- and western-type wolves historically mixed and hybridized in Minnesota and continue to do so. Our findings are relevant to a recent government proposal to delist wolves from the endangered species list in Minnesota and surrounding states.

An analysis of risk factors for pancreatic fistula after robotic pancreaticoduodenectomy: outcomes from a consecutive series of standardized pancreatic reconstructions.

PubMed

Polanco, Patricio M; Zenati, Mazen S; Hogg, Melissa E; Shakir, Murtaza; Boone, Brian A; Bartlett, David L; Zeh, Herbert J; Zureikat, Amer H

2016-04-01

Proponents of the robotic platform site its potential advantages in complex reconstructions such as the pancreaticojejunal anastomosis; however, the incidence and risk factors for postoperative pancreatic fistula (POPF) after robotic pancreaticoduodenectomy (RPD) have not been characterized. To identify independent risk factors for POPF after RPD. A prospectively maintained database of patients that underwent RPD (2008-2013) with a standardized pancreaticojejunostomy was analyzed. Univariate and multivariate analyses (UVA/MVA) were used to identify independent predictors for POPF. The POPF prognostic scores developed by Braga and Callery for open pancreaticoduodenectomy were then applied with logistic regression analysis on this RPD cohort. One hundred and fifty consecutive RPDs were analyzed. POPF occurred in 26 (17.3%); 13 (8.6%) of which were ISGPF category B and C. On UVA, patients with POPF had larger body mass index (BMI), smaller pancreatic duct diameter, smaller tumor size, longer OR time, larger estimated blood loss (EBL) and RBC transfusion (all p < 0.05). Higher EBL, duct size <4 mm, larger BMI and small tumor size remained the best independent risk factors for POPF on MVA. Increased Callery (OR 1.46, 95% CI, p = 0.001) and Braga (OR 1.2, 95% CI, p = 0.005) scores predicted an increased risk of POPF in this RPD cohort. Larger BMI, higher EBL, smaller tumor size and smaller duct diameter are the main predictors of POPF in RPD.

[Current problems of school education and ways of its hygienic optimization].

PubMed

Stepanova, M I; Sazaniuk, Z I; Voronova, B Z; Polenova, M A

2009-01-01

The aim of the study was to analyse effects of various innovative forms of school education on the health status and functional abilities of children and adolescents. Enhanced academic loads are shown to be the most unfavourable factor of the school environment. The main consequences of excess teaching load are shortened motor and outdoor activities of the children, smaller duration of night sleep. Optimization of academic routine (alternation of studies and holidays), modular structure of school calendar might help to reduce fatigue during school hours. Hygienic estimates of different variants of specialized education are obtained. Scientifically sound hygienic requirements are proposed to be applied to the organization of academic activities in a new type of educational institutions, full-day schools.

Anovulatory and ovulatory infertility: results with simplified management.

PubMed Central

Hull, M G; Savage, P E; Bromham, D R

1982-01-01

A simplified scheme for the management of anovulatory and of ovulatory (usually called unexplained) infertility was evaluated in 244 women. Eighteen patients were excluded because of primary ovarian failure, 164 were treated for ovulatory failure, and 62 with ovulatory infertility remained untreated. Twenty-five patients had a properly validated negative postcoital test. In the remaining 201 patients the two-year conception rates were 96% in patients with amenorrhoea, 83% in those with oligomenorrhoea, 74% in those with luteal deficiency, and 88% in those with ovulatory infertility. Comparison with normal rates implied that amenorrhoea represents a pure form of ovulatory failure that is completely correctable whereas in other conditions unexplained factors also contribute to infertility though to a much smaller extent than was previously thought. PMID:6805656

Characters and phylogenetic relationships of nectar-feeding bats, with descriptions of new Lonchophylla from western South America (Mammalia: Chiroptera: Phyllostomidae: Lonchophyllini)

USGS Publications Warehouse

Woodman, N.; Timm, R.M.

2006-01-01

The Neotropical Lonchophyllini (Chiropter: Phyllostomidae) currently comprise four genera and thirteen species of nectar-feeding bats. These species often are separated into larger-bodied (eight species) and smaller-bodied (five species) forms to aid in identification. Our morphological and morphometrical analyses of the smaller Lonchophyllini revealed the existence of two distinctive, previously undescribed species of bats of the genus Lonchophylla from western South America. We describe a new form from Amazonian Peru as Lonchophylla pattoni and one from western Colombia as Lonchophylla cadenai. Phyllogenetic analysis of the Lonchophyllini based primarily on morphological characters indicates that these two new species are closely related to Lonchophylla thomasi.

Charmless B_{(s)}→ VV decays in factorization-assisted topological-amplitude approach

NASA Astrophysics Data System (ADS)

Wang, Chao; Zhang, Qi-An; Li, Ying; Lü, Cai-Dian

2017-05-01

Within the factorization-assisted topological-amplitude approach, we studied the 33 charmless B_{(s)} → VV decays, where V stands for a light vector meson. According to the flavor flows, the amplitude of each process can be decomposed into eight different topologies. In contrast to the conventional flavor diagrammatic approach, we further factorize each topological amplitude into decay constant, form factors and unknown universal parameters. By χ ^2 fitting 46 experimental observables, we extracted 10 theoretical parameters with χ ^2 per degree of freedom around 2. Using the fitted parameters, we calculated the branching fractions, polarization fractions, CP asymmetries and relative phases between polarization amplitudes of each decay mode. The decay channels dominated by tree diagram have large branching fractions and large longitudinal polarization fraction. The branching fractions and longitudinal polarization fractions of color-suppressed decays become smaller. Current experimental data of large transverse polarization fractions in the penguin dominant decay channels can be explained by only one transverse amplitude of penguin annihilation diagram. Our predictions of the not yet measured channels can be tested in the ongoing LHCb experiment and the Belle-II experiment in the future.

On the glitches in the force transmitted by an electrodynamic exciter to a structure

NASA Technical Reports Server (NTRS)

Rao, Dantam K.

1987-01-01

Around resonance, the force transmitted by an exciter into a structure will be smaller or greater than a reference force generated by its coils due to electromechanical interaction. A simple analysis is presented which reveals how this phenomenon of force drop-off is controlled by three factors. The first factor, called Armature Mass Factor, describes a purely mechanical interaction between the structure and the exciter. The electromechanical energy conversion and its interaction with the structure yields two additional factors, called Electrical Resistance and Electrical Inductance Factors. They describe the effects of coil resistance, inductance and magnetic field strength relative to structural damping and stiffness. Present analysis indicates that, under proper circumstances, more than 90 percent of the force drop-off can be eliminated if armature-to-structure mass ratio is smaller or equal to half of modal loss factor.

Weak charge form factor and radius of 208Pb through parity violation in electron scattering

DOE PAGES

Horowitz, C. J.; Ahmed, Z.; Jen, C. -M.; ...

2012-03-26

We use distorted wave electron scattering calculations to extract the weak charge form factor F W(more » $$\\bar{q}$$), the weak charge radius R W, and the point neutron radius R n, of 208Pb from the PREX parity violating asymmetry measurement. The form factor is the Fourier transform of the weak charge density at the average momentum transfer $$\\bar{q}$$ = 0.475 fm -1. We find F W($$\\bar{q}$$) = 0.204 ± 0.028(exp) ± 0.001(model). We use the Helm model to infer the weak radius from F W($$\\bar{q}$$). We find RW = 5.826 ± 0.181(exp) ± 0.027(model) fm. Here the exp error includes PREX statistical and systematic errors, while the model error describes the uncertainty in R W from uncertainties in the surface thickness σ of the weak charge density. The weak radius is larger than the charge radius, implying a 'weak charge skin' where the surface region is relatively enriched in weak charges compared to (electromagnetic) charges. We extract the point neutron radius R n = 5.751 ± 0.175 (exp) ± 0.026(model) ± 0.005(strange) fm, from R W. Here there is only a very small error (strange) from possible strange quark contributions. We find R n to be slightly smaller than R W because of the nucleon's size. As a result, we find a neutron skin thickness of R n-R p = 0.302 ± 0.175 (exp) ± 0.026 (model) ± 0.005 (strange) fm, where R p is the point proton radius.« less

Compound cooling flow turbulator for turbine component

DOEpatents

Lee, Ching-Pang; Jiang, Nan; Marra, John J; Rudolph, Ronald J

2014-11-25

Multi-scale turbulation features, including first turbulators (46, 48) on a cooling surface (44), and smaller turbulators (52, 54, 58, 62) on the first turbulators. The first turbulators may be formed between larger turbulators (50). The first turbulators may be alternating ridges (46) and valleys (48). The smaller turbulators may be concave surface features such as dimples (62) and grooves (54), and/or convex surface features such as bumps (58) and smaller ridges (52). An embodiment with convex turbulators (52, 58) in the valleys (48) and concave turbulators (54, 62) on the ridges (46) increases the cooling surface area, reduces boundary layer separation, avoids coolant shadowing and stagnation, and reduces component mass.

The Spatial-temperal Distribution of Phosphorus Species and the Main Factors Influencing on Phosphorus Transportation in Middle Reaches of the Yarlung Zangbo River, China

NASA Astrophysics Data System (ADS)

Pu, X.; An, R.; Li, R.; Huang, W.; Li, J.

2017-12-01

The objectives of the current study are to investigate the spatial, temperal variation of phisphorus (P) fraction in middle reaches of the Yarlung Zangbo River of China. Samples were collected in April (dry season), August (wet season), and Octber (normal season) along with the middle reaches from Lazi site to Nuxia sitewhich which is about 1000km long. Sequential extraction were applied to determine the forms of phosphorus in suspended particles and to assess the potential bioavailability of particulate P. The results indicated that the distribution of suspended particle size inflenced not only the total phosphorus concentration, but also the proportions of different forms of phosphorus. The exchangeable phosphorus (Ex-P), Fe-bound-P, Ca-bound-P were the most aboundant forms and the highest proportions of total P. The total P concentrations were closely relative to the concentration of suspended particles. According to the characteristics of suspended particles in the Yarlung Zangbo River, the relationship between the suspended particles size and species of phosphorus was established though statistical analysis. The Ex-P increased with the decreasing of suspended particulate size. The content of bioavailable particulate phosphorus varied greatly with the proportions of particulate size. In genral, the higher the proportion of smaller particle size, the higher the content of bioavailable phosphorus. The main factors which affect the phosphorus transportation in Yarlung Zangbo River had also been discussed.

Evaluation of cluster expansions and correlated one-body properties of nuclei

NASA Astrophysics Data System (ADS)

Moustakidis, Ch. C.; Massen, S. E.; Panos, C. P.; Grypeos, M. E.; Antonov, A. N.

2001-07-01

Three different cluster expansions for the evaluation of correlated one-body properties of s-p and s-d shell nuclei are compared. Harmonic oscillator wave functions and Jastrow-type correlations are used, while analytical expressions are obtained for the charge form factor, density distribution, and momentum distribution by truncating the expansions and using a standard Jastrow correlation function f. The harmonic oscillator parameter b and the correlation parameter β have been determined by a least-squares fit to the experimental charge form factors in each case. The information entropy of nuclei in position space (Sr) and momentum space (Sk) according to the three methods are also calculated. It is found that the larger the entropy sum, S=Sr+Sk (the net information content of the system), the smaller the values of χ2. This indicates that maximal S is a criterion of the quality of a given nuclear model, according to the maximum entropy principle. Only two exceptions to this rule, out of many cases examined, were found. Finally an analytic expression for the so-called ``healing'' or ``wound'' integrals is derived with the function f considered, for any state of the relative two-nucleon motion, and their values in certain cases are computed and compared.

Identification and characterization of secondary neural tube-derived embryonic neural stem cells in vitro.

PubMed

Shaker, Mohammed R; Kim, Joo Yeon; Kim, Hyun; Sun, Woong

2015-05-15

Secondary neurulation is an embryonic progress that gives rise to the secondary neural tube, the precursor of the lower spinal cord region. The secondary neural tube is derived from aggregated Sox2-expressing neural cells at the dorsal region of the tail bud, which eventually forms rosette or tube-like structures to give rise to neural tissues in the tail bud. We addressed whether the embryonic tail contains neural stem cells (NSCs), namely secondary NSCs (sNSCs), with the potential for self-renewal in vitro. Using in vitro neurosphere assays, neurospheres readily formed at the rosette and neural-tube levels, but less frequently at the tail bud tip level. Furthermore, we identified that sNSC-generated neurospheres were significantly smaller in size compared with cortical neurospheres. Interestingly, various cell cycle analyses revealed that this difference was not due to a reduction in the proliferation rate of NSCs, but rather the neuronal commitment of sNSCs, as sNSC-derived neurospheres contain more committed neuronal progenitor cells, even in the presence of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF). These results suggest that the higher tendency for sNSCs to spontaneously differentiate into progenitor cells may explain the limited expansion of the secondary neural tube during embryonic development.

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

Hendler, Nathanial P.; Mulders, Gijs D.; Pascucci, Ilaria

The properties of disks around brown dwarfs and very low mass stars (hereafter VLMOs) provide important boundary conditions on the process of planet formation and inform us about the numbers and masses of planets than can form in this regime. We use the Herschel Space Observatory PACS spectrometer to measure the continuum and [O i] 63 μ m line emission toward 11 VLMOs with known disks in the Taurus and Chamaeleon I star-forming regions. We fit radiative transfer models to the spectral energy distributions of these sources. Additionally, we carry out a grid of radiative transfer models run in amore » regime that connects the luminosity of our sources with brighter T Tauri stars. We find that VLMO disks with sizes 1.3–78 au, smaller than typical T Tauri disks, fit well the spectral energy distributions assuming that disk geometry and dust properties are stellar mass independent. Reducing the disk size increases the disk temperature, and we show that VLMOs do not follow previously derived disk temperature–stellar luminosity relationships if the disk outer radius scales with stellar mass. Only 2 out of 11 sources are detected in [O i] despite a better sensitivity than was achieved for T Tauri stars, suggesting that VLMO disks are underluminous. Using thermochemical models, we show that smaller disks can lead to the unexpected [O i] 63 μ m nondetections in our sample. The disk outer radius is an important factor in determining the gas and dust observables. Hence, spatially resolved observations with ALMA—to establish if and how disk radii scale with stellar mass—should be pursued further.« less

Efficiency enhancement of blue light emitting diodes by eliminating V-defects from InGaN/GaN multiple quantum well structures through GaN capping layer control

NASA Astrophysics Data System (ADS)

Tsai, Sheng-Chieh; Li, Ming-Jui; Fang, Hsin-Chiao; Tu, Chia-Hao; Liu, Chuan-Pu

2018-05-01

A facile method for fabricating blue light-emitting diodes (B-LEDs) with small embedded quantum dots (QDs) and enhanced light emission is demonstrated by tuning the temperature of the growing GaN capping layer to eliminate V-defects. As the growth temperature increases from 770 °C to 840 °C, not only does the density of the V-defects reduce from 4.12 ∗ 108 #/cm2 nm to zero on a smooth surface, but the QDs also get smaller. Therefore, the growth mechanism of smaller QDs assisted by elimination of V-defects is discussed. Photoluminescence and electroluminescence results show that smaller embedded QDs can improve recombination efficiency, and thus achieve higher peak intensity with smaller peak broadening. Accordingly, the external quantum efficiency of the B-LEDs with smaller QDs is enhanced, leading to a 6.8% increase in light output power in lamp-form package LEDs.

Human Factors Engineering Requirements for the International Space Station - Successes and Challenges

NASA Technical Reports Server (NTRS)

Whitmore, M.; Blume, J.

2003-01-01

Advanced technology coupled with the desire to explore space has resulted in increasingly longer human space missions. Indeed, any exploration mission outside of Earth's neighborhood, in other words, beyond the moon, will necessarily be several months or even years. The International Space Station (ISS) serves as an important advancement toward executing a successful human space mission that is longer than a standard trip around the world or to the moon. The ISS, which is a permanently occupied microgravity research facility orbiting the earth, will support missions four to six months in duration. In planning for the ISS, the NASA developed an agency-wide set of human factors standards for the first time in a space exploration program. The Man-Systems Integration Standard (MSIS), NASA-STD-3000, a multi-volume set of guidelines for human-centered design in microgravity, was developed with the cooperation of human factors experts from various NASA centers, industry, academia, and other government agencies. The ISS program formed a human factors team analogous to any major engineering subsystem. This team develops and maintains the human factors requirements regarding end-to-end architecture design and performance, hardware and software design requirements, and test and verification requirements. It is also responsible for providing program integration across all of the larger scale elements, smaller scale hardware, and international partners.

Formation of mushrooms and lignocellulose degradation encoded in the genome sequence of Schizophyllum commune

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

Ohm, Robin A.; de Jong, Jan F.; Lugones, Luis G.

2010-07-12

The wood degrading fungus Schizophyllum commune is a model system for mushroom development. Here, we describe the 38.5 Mb assembled genome of this basidiomycete and application of whole genome expression analysis to study the 13,210 predicted genes. Comparative analyses of the S. commune genome revealed unique wood degrading machinery and mating type loci with the highest number of reported genes. Gene expression analyses revealed that one third of the 471 identified transcription factor genes were differentially expressed during sexual development. Two of these transcription factor genes were deleted. Inactivation of fst4 resulted in the inability to form mushrooms, whereas inactivationmore » of fst3 resulted in more but smaller mushrooms than wild-type. These data illustrate that mechanisms underlying mushroom formation can be dissected using S. commune as a model. This will impact commercial production of mushrooms and the industrial use of these fruiting bodies to produce enzymes and pharmaceuticals.« less

Tunable Supermode Dielectric Resonators for Axion Dark-Matter Haloscopes

NASA Astrophysics Data System (ADS)

McAllister, Ben T.; Flower, Graeme; Tobar, Lucas E.; Tobar, Michael E.

2018-01-01

We present frequency-tuning mechanisms for dielectric resonators, which undergo "supermode" interactions as they tune. The tunable schemes are based on dielectric materials strategically placed inside traditional cylindrical resonant cavities, necessarily operating in transverse-magnetic modes for use in axion haloscopes. The first technique is based on multiple dielectric disks with radii smaller than that of the cavity. The second scheme relies on hollow dielectric cylinders similar to a Bragg resonator, but with a different location and dimension. Specifically, we engineer a significant increase in form factor for the TM030 mode utilizing a variation of a distributed Bragg reflector resonator. Additionally, we demonstrate an application of traditional distributed Bragg reflectors in TM modes which may be applied to a haloscope. Theoretical and experimental results are presented showing an increase in Q factor and tunability due to the supermode effect. The TM030 ring-resonator mode offers a between 1 and 2-order-of-magnitude improvement in axion sensitivity over current conventional cavity systems and will be employed in the forthcoming ORGAN experiment.

Solar energy demand (SED) of commodity life cycles.

PubMed

Rugani, Benedetto; Huijbregts, Mark A J; Mutel, Christopher; Bastianoni, Simone; Hellweg, Stefanie

2011-06-15

The solar energy demand (SED) of the extraction of 232 atmospheric, biotic, fossil, land, metal, mineral, nuclear, and water resources was quantified and compared with other energy- and exergy-based indicators. SED represents the direct and indirect solar energy required by a product or service during its life cycle. SED scores were calculated for 3865 processes, as implemented in the Ecoinvent database, version 2.1. The results showed that nonrenewable resources, and in particular minerals, formed the dominant contribution to SED. This large share is due to the indirect solar energy required to produce these resource inputs. Compared with other energy- and exergy-based indicators, SED assigns higher impact factors to minerals and metals and smaller impact factors to fossil energetic resources, land use, and nuclear energy. The highest differences were observed for biobased and renewable energy generation processes, whose relative contribution of renewable resources such as water, biomass, and land occupation was much lower in SED than in energy- and exergy-based indicators.

Influence of two-stream relativistic electron beam parameters on the space-charge wave with broad frequency spectrum formation

NASA Astrophysics Data System (ADS)

Alexander, LYSENKO; Iurii, VOLK

2018-03-01

We developed a cubic non-linear theory describing the dynamics of the multiharmonic space-charge wave (SCW), with harmonics frequencies smaller than the two-stream instability critical frequency, with different relativistic electron beam (REB) parameters. The self-consistent differential equation system for multiharmonic SCW harmonic amplitudes was elaborated in a cubic non-linear approximation. This system considers plural three-wave parametric resonant interactions between wave harmonics and the two-stream instability effect. Different REB parameters such as the input angle with respect to focusing magnetic field, the average relativistic factor value, difference of partial relativistic factors, and plasma frequency of partial beams were investigated regarding their influence on the frequency spectrum width and multiharmonic SCW saturation levels. We suggested ways in which the multiharmonic SCW frequency spectrum widths could be increased in order to use them in multiharmonic two-stream superheterodyne free-electron lasers, with the main purpose of forming a powerful multiharmonic electromagnetic wave.

Effect of moisture on the fatigue behavior of graphite/epoxy composite laminates

NASA Technical Reports Server (NTRS)

Ramani, S. V.; Nelson, H. G.

1979-01-01

The form of the moisture distribution in the specimen (gradient and flat profile) was considered to establish the influence of accelerated moisture conditioning on fatigue behavior. For the gradient specimens having an average moisture content of 1.4 percent, fatigue life was reduced by a factor of 8 at all stress levels investigated. Corresponding reduction in fatigue life for the flat moisture profile specimens at the same average moisture content was comparatively smaller, being about a factor of 5 from the value in dry specimens. X-ray radiographic analysis of damage accumulation in compression-compression fatigue revealed interlaminar cracking to be the dominant mode of failure responsible for the observed enhanced cyclic degradation of moisture-conditioned specimens. This finding was corroborated by the observed systematic reduction in interlaminar shear strength as a function of moisture content, which, in turn, increased the propensity for delamination under cyclic compressive loads. Residual strength measurements on cycled specimens indicated significant strength reductions at long lives, particularly in moisture conditioned specimens.

Group A Streptococcal vaccine candidate: contribution of epitope to size, antigen presenting cell interaction and immunogenicity.

PubMed

Zaman, Mehfuz; Chandrudu, Saranya; Giddam, Ashwini K; Reiman, Jennifer; Skwarczynski, Mariusz; McPhun, Virginia; Moyle, Peter M; Batzloff, Michael R; Good, Michael F; Toth, Istvan

2014-12-01

Utilize lipopeptide vaccine delivery system to develop a vaccine candidate against Group A Streptococcus. Lipopeptides synthesized by solid-phase peptide synthesis-bearing carboxyl (C)-terminal and amino (N)-terminal Group A Streptococcus peptide epitopes. Nanoparticles formed were evaluated in vivo. Immune responses were induced in mice without additional adjuvant. We demonstrated for the first time that incorporation of the C-terminal epitope significantly enhanced the N-terminal epitope-specific antibody response and correlated with forming smaller nanoparticles. Antigen-presenting cells had increased uptake and maturation by smaller, more immunogenic nanoparticles. Antibodies raised by vaccination recognized isolates. Demonstrated the lipopeptidic nanoparticles to induce an immune response which can be influenced by the combined effect of epitope choice and size.

Self-Sorting of Bidispersed Colloidal Particles Near Contact Line of an Evaporating Sessile Droplet.

PubMed

Patil, Nagesh D; Bhardwaj, Rajneesh; Sharma, Atul

2018-06-13

Here, we investigate deposit patterns and associated morphology formed after the evaporation of an aqueous droplet containing mono- and bidispersed colloidal particles. In particular, the combined effect of substrate heating and particle diameter is investigated. We employ high-speed visualization, optical microscopy, and scanning electron microscopy to characterize the evaporating droplets, particle motion, and deposit morphology, respectively. In the context of monodispersed colloidal particles, an inner deposit and a typical ring form for smaller and larger particles, respectively, on a nonheated surface. The formation of the inner deposit is attributed to early depinning of the contact line, explained by a mechanistic model based on the balance of several forces acting on a particle near the contact line. At larger substrate temperature, a thin ring with inner deposit forms, explained by the self-pinning of the contact line and advection of the particles from the contact line to the center of the droplet due to the Marangoni flow. In the context of bidispersed colloidal particles, self-sorting of the colloidal particles within the ring occurs at larger substrate temperature. The smaller particles deposit at the outermost edge compared to the larger particles, and this preferential deposition in a stagnation region near the contact line is due to the spatially varying height of the liquid-gas interface above the substrate. The sorting occurs at a smaller ratio of the diameters of the smaller and larger particles. At larger substrate temperature and larger ratio, the particles do not get sorted and mix into each other. Our measurements show that there exists a critical substrate temperature as well as a diameter ratio to achieve the sorting. We propose regime maps on substrate temperature-particle diameter and substrate temperature-diameter ratio plane for mono- and bidispersed solutions, respectively.

Comment on 'Parametrization of Stillinger-Weber potential based on a valence force field model: application to single-layer MoS2 and black phosphorus'.

PubMed

Midtvedt, Daniel; Croy, Alexander

2016-06-10

We compare the simplified valence-force model for single-layer black phosphorus with the original model and recent ab initio results. Using an analytic approach and numerical calculations we find that the simplified model yields Young's moduli that are smaller compared to the original model and are almost a factor of two smaller than ab initio results. Moreover, the Poisson ratios are an order of magnitude smaller than values found in the literature.

Asymmetric planar gradiometer for rejection of uniform ambient magnetic noise

DOEpatents

Dantsker, Eugene; Clarke, John

2000-01-01

An asymmetric planar gradiometer for use in making biomagnetic measurements. The gradiometer is formed from a magnetometer which is inductively-coupled to the smaller of two connected loops patterned in a superconducting film which form a flux transformer. The magnetometer is based on a SQUID formed from a high T.sub.c superconducting material. The flux transformer and magnetometer may be formed on separate substrates, allowing the baseline to be increased relative to presently available devices.

77 FR 54434 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-05

...) other natural or manmade factors affecting its continued existence. We reviewed all available scientific...) (Eastwood 1905, p. 201; Chasse et al. 2009, p. 39). Its mahogany brown fruits are about 6 to 8 millimeters..., fruits that are smaller and less red in color, and flowers that are smaller and more spherical (Service...

Predictive equations for total lung capacity and residual volume calculated from radiographs in a random sample of the Michigan population.

PubMed Central

Kilburn, K H; Warshaw, R H; Thornton, J C; Thornton, K; Miller, A

1992-01-01

BACKGROUND: Published predicted values for total lung capacity and residual volume are often based on a small number of subjects and derive from different populations from predicted spirometric values. Equations from the only two large studies gave smaller predicted values for total lung capacity than the smaller studies. A large number of subjects have been studied from a population which has already provided predicted values for spirometry and transfer factor for carbon monoxide. METHODS: Total lung capacity was measured from standard posteroanterior and lateral chest radiographs and forced vital capacity by spirometry in a population sample of 771 subjects. Prediction equations were developed for total lung capacity (TLC), residual volume (RV) and RV/TLC in two groups--normal and total. Subjects with signs or symptoms of cardiopulmonary disease were combined with the normal subjects and equations for all subjects were also modelled. RESULTS: Prediction equations for TLC and RV in non-smoking normal men and women were square root transformations which included height and weight but not age. They included a coefficient for duration of smoking in current smokers. The predictive equation for RV/TLC included weight, age, age and duration of smoking for current smokers and ex-smokers of both sexes. For the total population the equations took the same form but the height coefficients and constants were slightly different. CONCLUSION: These population based prediction equations for TLC, RV and RV/TLC provide reference standards in a population that has provided reference standards for spirometry and single breath transfer factor for carbon monoxide. PMID:1412094

Labor force participation and secondary education of gender inequality index (GII) associated with healthy life expectancy (HLE) at birth.

PubMed

Kim, Jong In; Kim, Gukbin

2014-11-18

What is the factor that affects healthy life expectancy? Healthy life expectancy (HLE) at birth may be influenced by components of the gender inequality index (GII). Notably, this claim is not tested on the between components of the GII, such as population at least secondary education (PLSE) with ages 25 and older, labor force participation rate (LFPR) with ages 15 and older, and the HLE in the world's countries. Thus, this study estimates the associations between the PLSE, LFPR of components of the GII and the HLE. The data for the analysis of HLE in 148 countries were obtained from the World Health Organization. Information regarding the GII indicators for this study was obtained from the United Nations database. Associations between these factors and HLE were assessed using Pearson correlation coefficients and regression models. Although significant negative correlations were found between HLE and the LFPR, positive correlations were found between HLE and PLSE. Finally, the HLE predictors were used to form a model of the components of the GII, with higher PLSE as secondary education and lower LFPR as labor force (R(2) = 0.552, P <0.001). Gender inequality of the attainment secondary education and labor force participation seems to have an important latent effect on healthy life expectancy at birth. Therefore, in populations with high HLE, the gender inequalities in HLE are smaller because of a combination of a larger secondary education advantage and a smaller labor force disadvantage in male-females.

Properties of amylose-oleic acid inclusion complexes from corn starch grafted with poly(methyl acrylate)

USDA-ARS?s Scientific Manuscript database

Corn starch granules have been previously investigated as fillers in polymers. In this study, much smaller particles in the form of spherulites produced by steam jet-cooking high-amylose corn starch and oleic acid to form amylose inclusion complexes were graft polymerized with methyl acrylate, both ...

Reductive cleavage of the peptide bond

NASA Technical Reports Server (NTRS)

Holian, J.; Garrison, W. M.

1973-01-01

In many biological research efforts, long chain organic molecules are studied by breaking large molecules into smaller components. Cleavage technique of recent interest is the use of solvated electrons. These are formed when aqueous solutions are bombarded with gamma radiation. Solvated electron is very reactive and can reduce most any species present, even to form free radicals.

Enhancing Energy in Future Conventional Munition

NASA Astrophysics Data System (ADS)

Peiris, Suhithi

2017-06-01

Future conventional weapons are envisioned to contain more energy per volume than current weapons. Current weapons comprise of inert steel outer case, with inner volume for energetic materials, fuzing, sensor package, propulsion system, etc. Recent research on reactive materials (RM) & new energetics, and exploiting additive manufacturing can optimize the use of both mass and volume to achieve much higher energy in future weapons. For instance, replacing inert steel with RM of similar strength, additively manufacturing fuzing packages within the weapon form factor, and combing the whole with new energetics, will enable the same lethality effects from smaller weapons as obtained from today's larger weapons. This paper will elaborate on reactive materials and properties necessary for optimal utilization in various weapon features, and touch on other aspects of enhancing energy in future conventional munition.

Chiral anomalies and effective vector meson Lagrangian beyond the tree level

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

Dominguez, C.A.

1987-12-01

The decays ..pi../sup O/ ..-->.. ..gamma gamma.., rho ..-->.. ..pi gamma.., ..omega.. ..-->.. ..pi gamma.., ..omega.. ..-->.. 3..pi.. and ..gamma.. ..-->.. 3..pi.. are studied in the framework of the chiral invariant effective Vector Meson Lagrangian beyond the tree level. The standard Lagrangian is enlarged by including an infinite number of radial excitations which are summed according to the dual model. As a result tree level diagrams are modified by a universal form factor at each vertex containing off-mass-shell mesons, but still respecting chiral anomaly low energy theorems. These vertex corrections bring the tree level predictions into better agreement with experiment.more » The presence of the ..omega.. ..-->.. 3..pi.. contact term is confirmed but its strength is considerably smaller than at tree level.« less

Evolution of magnetic disk subsystems

NASA Astrophysics Data System (ADS)

Kaneko, Satoru

1994-06-01

The higher recording density of magnetic disk realized today has brought larger storage capacity per unit and smaller form factors. If the required access performance per MB is constant, the performance of large subsystems has to be several times better. This article describes mainly the technology for improving the performance of the magnetic disk subsystems and the prospects of their future evolution. Also considered are 'crosscall pathing' which makes the data transfer channel more effective, 'disk cache' which improves performance coupling with solid state memory technology, and 'RAID' which improves the availability and integrity of disk subsystems by organizing multiple disk drives in a subsystem. As a result, it is concluded that since the performance of the subsystem is dominated by that of the disk cache, maximation of the performance of the disk cache subsystems is very important.

Cavity cooling a single charged levitated nanosphere.

PubMed

Millen, J; Fonseca, P Z G; Mavrogordatos, T; Monteiro, T S; Barker, P F

2015-03-27

Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

Cavity Cooling a Single Charged Levitated Nanosphere

NASA Astrophysics Data System (ADS)

Millen, J.; Fonseca, P. Z. G.; Mavrogordatos, T.; Monteiro, T. S.; Barker, P. F.

2015-03-01

Optomechanical cavity cooling of levitated objects offers the possibility for laboratory investigation of the macroscopic quantum behavior of systems that are largely decoupled from their environment. However, experimental progress has been hindered by particle loss mechanisms, which have prevented levitation and cavity cooling in a vacuum. We overcome this problem with a new type of hybrid electro-optical trap formed from a Paul trap within a single-mode optical cavity. We demonstrate a factor of 100 cavity cooling of 400 nm diameter silica spheres trapped in vacuum. This paves the way for ground-state cooling in a smaller, higher finesse cavity, as we show that a novel feature of the hybrid trap is that the optomechanical cooling becomes actively driven by the Paul trap, even for singly charged nanospheres.

Projection methods for the numerical solution of Markov chain models

NASA Technical Reports Server (NTRS)

Saad, Youcef

1989-01-01

Projection methods for computing stationary probability distributions for Markov chain models are presented. A general projection method is a method which seeks an approximation from a subspace of small dimension to the original problem. Thus, the original matrix problem of size N is approximated by one of dimension m, typically much smaller than N. A particularly successful class of methods based on this principle is that of Krylov subspace methods which utilize subspaces of the form span(v,av,...,A(exp m-1)v). These methods are effective in solving linear systems and eigenvalue problems (Lanczos, Arnoldi,...) as well as nonlinear equations. They can be combined with more traditional iterative methods such as successive overrelaxation, symmetric successive overrelaxation, or with incomplete factorization methods to enhance convergence.

A neuro-data envelopment analysis approach for optimization of uncorrelated multiple response problems with smaller the better type controllable factors

NASA Astrophysics Data System (ADS)

Bashiri, Mahdi; Farshbaf-Geranmayeh, Amir; Mogouie, Hamed

2013-11-01

In this paper, a new method is proposed to optimize a multi-response optimization problem based on the Taguchi method for the processes where controllable factors are the smaller-the-better (STB)-type variables and the analyzer desires to find an optimal solution with smaller amount of controllable factors. In such processes, the overall output quality of the product should be maximized while the usage of the process inputs, the controllable factors, should be minimized. Since all possible combinations of factors' levels, are not considered in the Taguchi method, the response values of the possible unpracticed treatments are estimated using the artificial neural network (ANN). The neural network is tuned by the central composite design (CCD) and the genetic algorithm (GA). Then data envelopment analysis (DEA) is applied for determining the efficiency of each treatment. Although the important issue for implementation of DEA is its philosophy, which is maximization of outputs versus minimization of inputs, this important issue has been neglected in previous similar studies in multi-response problems. Finally, the most efficient treatment is determined using the maximin weight model approach. The performance of the proposed method is verified in a plastic molding process. Moreover a sensitivity analysis has been done by an efficiency estimator neural network. The results show efficiency of the proposed approach.

Molecular Simulation of Receptor Occupancy and Tumor Penetration of an Antibody and Smaller Scaffolds: Application to Molecular Imaging.

PubMed

Orcutt, Kelly D; Adams, Gregory P; Wu, Anna M; Silva, Matthew D; Harwell, Catey; Hoppin, Jack; Matsumura, Manabu; Kotsuma, Masakatsu; Greenberg, Jonathan; Scott, Andrew M; Beckman, Robert A

2017-10-01

Competitive radiolabeled antibody imaging can determine the unlabeled intact antibody dose that fully blocks target binding but may be confounded by heterogeneous tumor penetration. We evaluated the hypothesis that smaller radiolabeled constructs can be used to more accurately evaluate tumor expressed receptors. The Krogh cylinder distributed model, including bivalent binding and variable intervessel distances, simulated distribution of smaller constructs in the presence of increasing doses of labeled antibody forms. Smaller constructs <25 kDa accessed binding sites more uniformly at large distances from blood vessels compared with larger constructs and intact antibody. These observations were consistent for different affinity and internalization characteristics of constructs. As predicted, a higher dose of unlabeled intact antibody was required to block binding to these distant receptor sites. Small radiolabeled constructs provide more accurate information on total receptor expression in tumors and reveal the need for higher antibody doses for target receptor blockade.

The true quantum face of the "exponential" decay: Unstable systems in rest and in motion

NASA Astrophysics Data System (ADS)

Urbanowski, K.

2017-12-01

Results of theoretical studies and numerical calculations presented in the literature suggest that the survival probability P0(t) has the exponential form starting from times much smaller than the lifetime τ up to times t ⪢τ and that P0(t) exhibits inverse power-law behavior at the late time region for times longer than the so-called crossover time T ⪢ τ (The crossover time T is the time when the late time deviations of P0(t) from the exponential form begin to dominate). More detailed analysis of the problem shows that in fact the survival probability P0(t) can not take the pure exponential form at any time interval including times smaller than the lifetime τ or of the order of τ and it has has an oscillating form. We also study the survival probability of moving relativistic unstable particles with definite momentum . These studies show that late time deviations of the survival probability of these particles from the exponential-like form of the decay law, that is the transition times region between exponential-like and non-exponential form of the survival probability, should occur much earlier than it follows from the classical standard considerations.

Relationship between variant forms of estrogen receptor RNA and an apoptosis-related RNA, TRPM-2, with survival in patients with breast cancer.

PubMed

Rennie, P S; Mawji, N R; Coldman, A J; Godolphin, W; Jones, E C; Vielkind, J R; Bruchovsky, N

1993-12-15

Although smaller variant forms of estrogen receptor (ER) messenger RNA (mRNA) have been detected in breast tumors, neither their prevalence nor their prognostic significance have been evaluated. Similarly, TRPM-2 mRNA, the product of a gene induced principally during the onset of apoptosis, is present in mouse and human breast cancer cell lines, but whether it also occurs in primary breast tumors and is related to disease outcome is unknown. The relative expression and transcript size of ER mRNA and TRPM-2 mRNA in 126 primary breast tumors were measured by Northern analysis and compared with tumor grade, hormone receptor status, extent of tumor necrosis, and survival. In ER-positive tumors, 64% of the tumors had only the normal 6.5 kb ER mRNA, an additional 9% had the normal plus smaller ER mRNA, and 2% had variant forms. Only 8% of ER-negative tumors had ER mRNA transcripts. There were significant relationships between the occurrence of ER mRNA and low tumor grade, ER-positive receptor status, and better survival. In contrast, TRPM-2 mRNA was found in only 17% of breast tumors, none of which could be grouped with respect to grade, hormone receptor status, or survival. The presence of smaller variant forms of ER mRNA either alone or in association with the normal ER transcript is not indicative of an unfavorable prognosis, whereas TRPM-2 mRNA occurs in many primary breast tumors, but has no apparent relationship to survival.

Flammutoxin, a cytolysin from the edible mushroom Flammulina velutipes, forms two different types of voltage-gated channels in lipid bilayer membranes.

PubMed

Tadjibaeva, G; Sabirov, R; Tomita, T

2000-08-25

Flammutoxin, a 31-kDa cardiotoxic and cytolytic protein from the edible mushroom Flammulina velutipes, has been shown to assemble into a pore-forming annular oligomer with outer and inner diameters of 10 and 5 nm on the target cells [Tomita et al., Biochem. J. 333 (1998) 129-137]. Here we studied electrophysiological properties of flammutoxin channels using planar lipid bilayer technique, and found that flammutoxin formed two types of moderately cation-selective, voltage-gated channels with smaller and larger current amplitudes (1-4.5 pA and 20-30 pA, respectively, at 20 mV) in the lipid bilayers composed of phospholipid and cholesterol. The larger-conductance single channel showed the properties of a wide water-filled pore such as a linear relationship between channel conductance and salt concentration of the bathing solution. The functional diameter of the larger-conductance channel was estimated to be 4-5 nm by measuring the current conductance in the presence of polyethylene glycols of various sizes. In contrast, the smaller-conductance single channels showed a non-linear current to voltage curve and a saturating conductance to increasing salt concentration. These results suggest that the larger-conductance channel of flammutoxin corresponds to the hemolytic pore complex, while the smaller-conductance channel may reflect the intermediate state(s) of the assembling toxin.

Bootstrap Standard Error Estimates in Dynamic Factor Analysis

ERIC Educational Resources Information Center

Zhang, Guangjian; Browne, Michael W.

2010-01-01

Dynamic factor analysis summarizes changes in scores on a battery of manifest variables over repeated measurements in terms of a time series in a substantially smaller number of latent factors. Algebraic formulae for standard errors of parameter estimates are more difficult to obtain than in the usual intersubject factor analysis because of the…

Hierarchical Factoring Based On Image Analysis And Orthoblique Rotations.

PubMed

Stankov, L

1979-07-01

The procedure for hierarchical factoring suggested by Schmid and Leiman (1957) is applied within the framework of image analysis and orthoblique rotational procedures. It is shown that this approach necessarily leads to correlated higher order factors. Also, one can obtain a smaller number of factors than produced by typical hierarchical procedures.

Cirrhosis - discharge

MedlinePlus

Liver failure - discharge; Liver cirrhosis - discharge ... You have cirrhosis of the liver. Scar tissue forms and your liver gets smaller and harder. Most of the time, this damage cannot be undone. However, the ...

Method and apparatus for semi-solid material processing

DOEpatents

Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

2009-02-24

A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming machine.

Method and apparatus for semi-solid material processing

DOEpatents

Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

2009-11-24

A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming maching.

Method and apparatus for semi-solid material processing

DOEpatents

Han, Qingyou [Knoxville, TN; Jian, Xiaogang [Knoxville, TN; Xu, Hanbing [Knoxville, TN; Meek, Thomas T [Knoxville, TN

2007-05-15

A method of forming a material includes the steps of: vibrating a molten material at an ultrasonic frequency while cooling the material to a semi-solid state to form non-dendritic grains therein; forming the semi-solid material into a desired shape; and cooling the material to a solid state. The method makes semi-solid castings directly from molten materials (usually a metal), produces grain size usually in the range of smaller than 50 .mu.m, and can be easily retrofitted into existing conventional forming machine.

Degradation and biocompatibility of multi-stage nanovectors in physiological systems

PubMed Central

Martinez, Jonathan O.; Evangelopoulos, Michael; Chiappini, Ciro; Liu, Xuewu; Ferrari, Mauro; Tasciotti, Ennio

2014-01-01

The careful scrutiny of drug delivery systems is essential to evaluate and justify their potential for the clinic. Among the various studies necessary for pre-clinical testing, the impact of degradation is commonly overlooked. In this paper, we investigate the effect of fabrication (porosity and nucleation layer) and environment (buffer and pH) factors on the degradation kinetics of multi-stage nanovectors (MSV) composed of porous silicon. The degradation by-products of MSV were exposed to endothelial cells and analyzed for detrimental effects on cellular internalization, architecture, proliferation, and cell cycle. Increases in porosity resulted in accelerated degradation exhibiting smaller sized particles at comparable times. Removal of the nucleation layer (thin layer of small pores formed during the initial steps of etching) triggered a premature collapse of the entire central porous region of MSV. Variations in buffers prompted a faster degradation rate yielding smaller MSV within faster time frames while increases in pH stimulated erosion of MSV and thus faster degradation. In addition, exposure to these degradation by-products provoked negligible impact on the proliferation and cell cycle phases on primary endothelial cells. Here, we propose methods that lay the foundation for future investigations towards understanding the impact of the degradation of drug delivery platforms. PMID:25269799

Subsurface temperature distribution in a tropical alluvial fan

NASA Astrophysics Data System (ADS)

Chen, Wenfu; Chang, Minhsiang; Chen, Juier; Lu, Wanchung; Huang, Chihc; Wang, Yunshuen

2017-04-01

As a groundwater intensive use country, Taiwan's 1/3 water supplies are derived from groundwater. The major aquifers consist of sand and gravel formed in alluvial fans which border the fronts of central mountains. Thanks to high density of monitoring wells which provide a window to see the details of the subsurface temperature distribution and the thermal regime in an alluvial fan system. Our study area, the Choshui Alluvial Fan, is the largest groundwater basin in Taiwan and, located within an area of 2,000 km2, has a population of over 1.5 million. For this work, we investigated temperature-depth profiles using 70 groundwater monitoring wells during 2000 to 2015. Our results show that the distribution of subsurface temperature is influenced by various factors such as groundwater recharge, groundwater flow field, air temperature and land use. The groundwater recharge zone, hills to the upper fan, contains disturbed and smaller geothermal gradients. The lack of clay layers within the upper fan aquifers and fractures that developed in the hills should cause the convection and mixing of cooler recharge water to groundwater, resulting in smaller geothermal gradients. The groundwater temperatures at a depth to 300 m within the upper fan and hill were approximately only 23-24 °C while the current mean ground surface temperature is approximately 26 °C.

75 FR 48294 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition to List...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-10

... manmade factors affecting its continued existence. (3) The potential effects of climate change on this.... 39). Its mahogany brown fruits are about 6 to 8 millimeters (mm) (0.24 to 0.32 in) wide, while its... prostrate growth habit, more rounded leaves, smaller and less reddish fruits, and smaller and more spherical...

An Investigation Examining the Perceived Implications of Principal Leadership Changing a Large Comprehensive High School into Smaller Learning Communities

ERIC Educational Resources Information Center

Miller, Raymond J.

2012-01-01

The purpose of this qualitative case study was to examine the perceived implications that principal leadership has on transforming a large comprehensive high school into smaller learning communities (SLCs); and to speculate on possible factors that contribute to the change process after the implementation of SLCs. The study explores the roles,…

Comprehensive Care

MedlinePlus

... also a priority. Your Whole Health, Your Whole Team: Managing Your Complex MS Symptoms Webinar/telelearning presented ... MS and how to form a comprehensive care team. Watch now Share Smaller Text Larger Text Print ...

Spontaneous emission in semiconductor laser amplifiers

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

Arnaud, J.; Coste, F.; Fesqueet, J.

1985-06-01

In a mode matched configuration, spontaneous emission in semiconductor laser amplifiers is enhanced by a factor which is larger than unity but which is significantly smaller than the K-factor calculated by Petermann. Using thin-slab model, we find that in typical situations, the factor is about K/2.

Establishing robust cognitive dimensions for characterization and differentiation of patients with Alzheimer's disease, mild cognitive impairment, frontotemporal dementia and depression.

PubMed

Beck, Irene R; Schmid, Nicole S; Berres, Manfred; Monsch, Andreas U

2014-06-01

The diagnosis of mild cognitive impairment (MCI) and dementia requires detailed neuropsychological examinations. These examinations typically yield a large number of outcome variables, which may complicate the interpretation and communication of results. The purposes of this study were the following: (i) to reduce a large data set of interrelated neuropsychological variables to a smaller number of cognitive dimensions; (ii) to create a common metric for these dimensions (z-scores); and (iii) to study the ability of the cognitive dimensions to distinguish between groups of patients with different types of cognitive impairment. We tested 1646 patients with different forms of dementia or with a major depression with a standard (n = 632) or, if cognitively less affected, a challenging neuropsychological battery (n = 1014). To identify the underlying cognitive dimensions of the two test batteries, maximum likelihood factor analyses with a promax rotation were conducted. To interpret the sum scores of the factors as standard scores, we divided them by the standard deviation of a cognitively healthy sample (n = 1145). The factor analyses yielded seven factors for each test battery. The cognitive dimensions in both test batteries distinguished patients with different forms of dementia (MCI, Alzheimer's dementia or frontotemporal dementia) and patients with major depression. Furthermore, patients with stable MCI could be separated from patients with progressing MCI. Discriminant analyses with an independent new sample of patients (n = 306) revealed that the new dimension scores distinguished new samples of patients with MCI from patients with Alzheimer's dementia with high accuracy. These findings suggest that these cognitive dimensions may benefit neuropsychological diagnostics. © 2013 The Authors International Journal of Geriatric Psychiatry Published by John Wiley & Sons Ltd.

Establishing robust cognitive dimensions for characterization and differentiation of patients with Alzheimer's disease, mild cognitive impairment, frontotemporal dementia and depression

PubMed Central

Beck, Irene R; Schmid, Nicole S; Berres, Manfred; Monsch, Andreas U

2014-01-01

Objective The diagnosis of mild cognitive impairment (MCI) and dementia requires detailed neuropsychological examinations. These examinations typically yield a large number of outcome variables, which may complicate the interpretation and communication of results. The purposes of this study were the following: (i) to reduce a large data set of interrelated neuropsychological variables to a smaller number of cognitive dimensions; (ii) to create a common metric for these dimensions (z-scores); and (iii) to study the ability of the cognitive dimensions to distinguish between groups of patients with different types of cognitive impairment. Methods We tested 1646 patients with different forms of dementia or with a major depression with a standard (n = 632) or, if cognitively less affected, a challenging neuropsychological battery (n = 1014). To identify the underlying cognitive dimensions of the two test batteries, maximum likelihood factor analyses with a promax rotation were conducted. To interpret the sum scores of the factors as standard scores, we divided them by the standard deviation of a cognitively healthy sample (n = 1145). Results The factor analyses yielded seven factors for each test battery. The cognitive dimensions in both test batteries distinguished patients with different forms of dementia (MCI, Alzheimer's dementia or frontotemporal dementia) and patients with major depression. Furthermore, patients with stable MCI could be separated from patients with progressing MCI. Discriminant analyses with an independent new sample of patients (n = 306) revealed that the new dimension scores distinguished new samples of patients with MCI from patients with Alzheimer's dementia with high accuracy. Conclusion These findings suggest that these cognitive dimensions may benefit neuropsychological diagnostics. PMID:24227657

Method and apparatus to control the lateral motion of a long metal bar being formed by a mechanical process such as rolling or drawing

DOEpatents

Chang, Tzyy-Shuh [Ann Arbor, MI; Huang, Hsun-Hau [Ann Arbor, MI; Lin, Chang-Hung [Ypsilanti, MI

2011-01-04

An apparatus to control lateral motion of a bar moving along a guidance path includes a pair of rotatable hubs each having at least first and second rollers at locations around the perimeter of the hub. The first roller has a first retaining groove of a first radius and the second roller has a second groove of a second radius smaller than the first radius. Each hub further includes at least one guiding element located between the rollers with a guide channel extending in the outer surface. A mounting system allows the hubs to be rotated between first and second positions. In the first position the first rollers oppose each other forming a guideway having a first, enlarged diameter for capturing a free end of an approaching bar. In the second position the second rollers form a second, smaller diameter to match the actual size of the bar.

Micro-heterogeneity versus clustering in binary mixtures of ethanol with water or alkanes.

PubMed

Požar, Martina; Lovrinčević, Bernarda; Zoranić, Larisa; Primorać, Tomislav; Sokolić, Franjo; Perera, Aurélien

2016-08-24

Ethanol is a hydrogen bonding liquid. When mixed in small concentrations with water or alkanes, it forms aggregate structures reminiscent of, respectively, the direct and inverse micellar aggregates found in emulsions, albeit at much smaller sizes. At higher concentrations, micro-heterogeneous mixing with segregated domains is found. We examine how different statistical methods, namely correlation function analysis, structure factor analysis and cluster distribution analysis, can describe efficiently these morphological changes in these mixtures. In particular, we explain how the neat alcohol pre-peak of the structure factor evolves into the domain pre-peak under mixing conditions, and how this evolution differs whether the co-solvent is water or alkane. This study clearly establishes the heuristic superiority of the correlation function/structure factor analysis to study the micro-heterogeneity, since cluster distribution analysis is insensitive to domain segregation. Correlation functions detect the domains, with a clear structure factor pre-peak signature, while the cluster techniques detect the cluster hierarchy within domains. The main conclusion is that, in micro-segregated mixtures, the domain structure is a more fundamental statistical entity than the underlying cluster structures. These findings could help better understand comparatively the radiation scattering experiments, which are sensitive to domains, versus the spectroscopy-NMR experiments, which are sensitive to clusters.

Hints for Small Disks around Very Low Mass Stars and Brown Dwarfs

NASA Astrophysics Data System (ADS)

Hendler, Nathanial P.; Mulders, Gijs D.; Pascucci, Ilaria; Greenwood, Aaron; Kamp, Inga; Henning, Thomas; Ménard, François; Dent, William R. F.; Evans, Neal J., II

2017-06-01

The properties of disks around brown dwarfs and very low mass stars (hereafter VLMOs) provide important boundary conditions on the process of planet formation and inform us about the numbers and masses of planets than can form in this regime. We use the Herschel Space Observatory PACS spectrometer to measure the continuum and [O I] 63 μm line emission toward 11 VLMOs with known disks in the Taurus and Chamaeleon I star-forming regions. We fit radiative transfer models to the spectral energy distributions of these sources. Additionally, we carry out a grid of radiative transfer models run in a regime that connects the luminosity of our sources with brighter T Tauri stars. We find that VLMO disks with sizes 1.3-78 au, smaller than typical T Tauri disks, fit well the spectral energy distributions assuming that disk geometry and dust properties are stellar mass independent. Reducing the disk size increases the disk temperature, and we show that VLMOs do not follow previously derived disk temperature-stellar luminosity relationships if the disk outer radius scales with stellar mass. Only 2 out of 11 sources are detected in [O I] despite a better sensitivity than was achieved for T Tauri stars, suggesting that VLMO disks are underluminous. Using thermochemical models, we show that smaller disks can lead to the unexpected [O I] 63 μm nondetections in our sample. The disk outer radius is an important factor in determining the gas and dust observables. Hence, spatially resolved observations with ALMA—to establish if and how disk radii scale with stellar mass—should be pursued further. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Actions of brain-derived neurotrophic factor on evoked and spontaneous EPSCs dissociate with maturation of neurones cultured from rat visual cortex

PubMed Central

Taniguchi, Nobuaki; Takada, Naoki; Kimura, Fumitaka; Tsumoto, Tadaharu

2000-01-01

To address the question of whether brain-derived neurotrophic factor (BDNF) directly enhances excitatory synaptic transmission, we recorded excitatory postsynaptic currents (EPSCs) from solitary neurones cultured on glial microislands for 7–38 days, and observed changes in EPSCs after the application of BDNF. In this preparation the possible action of BDNF on GABAergic inhibition was not involved, and evoked and spontaneous (miniature) EPSCs were derived from the same group of synapses (autapses). The application of BDNF at a concentration of 200 ng ml−1 rapidly enhanced the frequency of miniature EPSCs (mEPSCs) in almost all the neurones tested. On the other hand, the amplitude of mEPSCs did not change at all, suggesting that the site of BDNF action is presynaptic. In contrast to the enhanced frequency of mEPSCs, evoked EPSCs were not potentiated in 61 % of the cells tested. Most of these BDNF-insensitive EPSCs had a peak amplitude larger than 1 nA, while most of the other BDNF-sensitive EPSCs had a smaller amplitude. The former EPSCs had smaller coefficients of variation (CVs) of amplitude, while the latter had larger CVs, suggesting the possibility that the presynaptic release probability for the former groups of EPSCs might have beeen saturated so that the BDNF action was occluded. To test this possibility we applied a low Ca2+ solution to 17 cells and reduced the amplitude of their evoked EPSCs to less than or near to 1 nA. It was found, however, that BDNF did not enhance these EPSCs. Rather, evoked EPSCs of almost all the cells cultured for less than 15 days were enhanced by BDNF, while those of most of the cells cultured for longer than 16 days were not enhanced. These results suggest that BDNF enhances transmitter release from presynaptic sites through its action on the release machinery, which can be differentiated into a BDNF-insensitive form for evoked release and a BDNF-sensitive form for spontaneous release with maturation of synapses. PMID:10990542

School Students' Ideas about Air Pollution: Knowledge and Attitudes

ERIC Educational Resources Information Center

Myers, George; Boyes, Edward; Stanisstreet, Martin

2004-01-01

The understanding of pupils in schools in England between the ages of 11 and 16 about air and air pollution has been studied using a closed-form questionnaire with over a thousand students. Items for the questionnaire were derived from the results of an earlier open-form questionnaire completed by a smaller number of students. The ideas explored…

The Past and Likely Future of an Educational Form: A Textbook Case

ERIC Educational Resources Information Center

Friesen, Norm

2013-01-01

At a time when it is seen as increasingly "obsolete," this article analyzes the textbook as an evolving pedagogical form, as a changing medium comprised of smaller media components. These components include images, diagrams and also oral prompts, which have changed not so much through technical innovation as in synchrony with larger…

Presidential Search: Selecting the Top Candidates.

ERIC Educational Resources Information Center

Stead, Ronald S.

1988-01-01

The winnowing of a large number of presidential candidates to a smaller, more manageable group is discussed. Initial screening, candidate information, evaluation form, reference checking, and selecting interviewees are described. (MLW)

Heart Disease in Women: Understand Symptoms and Risk Factors

MedlinePlus

... menopause pose a significant risk factor for developing cardiovascular disease in the smaller blood vessels (coronary microvascular disease). ... treat breast cancer, may increase the risk of cardiovascular disease. Pregnancy complications. High blood pressure or diabetes during ...

Elongated Nanoparticle Aggregates in Cancer Cells for Mechanical Destruction with Low Frequency Rotating Magnetic Field.

PubMed

Shen, Yajing; Wu, Congyu; Uyeda, Taro Q P; Plaza, Gustavo R; Liu, Bin; Han, Yu; Lesniak, Maciej S; Cheng, Yu

2017-01-01

Magnetic nanoparticles (MNPs) functionalized with targeting moieties can recognize specific cell components and induce mechanical actuation under magnetic field. Their size is adequate for reaching tumors and targeting cancer cells. However, due to the nanometric size, the force generated by MNPs is smaller than the force required for largely disrupting key components of cells. Here, we show the magnetic assembly process of the nanoparticles inside the cells, to form elongated aggregates with the size required to produce elevated mechanical forces. We synthesized iron oxide nanoparticles doped with zinc, to obtain high magnetization, and functionalized with the epidermal growth factor (EGF) peptide for targeting cancer cells. Under a low frequency rotating magnetic field at 15 Hz and 40 mT, the internalized EGF-MNPs formed elongated aggregates and generated hundreds of pN to dramatically damage the plasma and lysosomal membranes. The physical disruption, including leakage of lysosomal hydrolases into the cytosol, led to programmed cell death and necrosis. Our work provides a novel strategy of designing magnetic nanomedicines for mechanical destruction of cancer cells.

Elongated Nanoparticle Aggregates in Cancer Cells for Mechanical Destruction with Low Frequency Rotating Magnetic Field

PubMed Central

Shen, Yajing; Wu, Congyu; Uyeda, Taro Q. P.; Plaza, Gustavo R.; Liu, Bin; Han, Yu; Lesniak, Maciej S.; Cheng, Yu

2017-01-01

Magnetic nanoparticles (MNPs) functionalized with targeting moieties can recognize specific cell components and induce mechanical actuation under magnetic field. Their size is adequate for reaching tumors and targeting cancer cells. However, due to the nanometric size, the force generated by MNPs is smaller than the force required for largely disrupting key components of cells. Here, we show the magnetic assembly process of the nanoparticles inside the cells, to form elongated aggregates with the size required to produce elevated mechanical forces. We synthesized iron oxide nanoparticles doped with zinc, to obtain high magnetization, and functionalized with the epidermal growth factor (EGF) peptide for targeting cancer cells. Under a low frequency rotating magnetic field at 15 Hz and 40 mT, the internalized EGF-MNPs formed elongated aggregates and generated hundreds of pN to dramatically damage the plasma and lysosomal membranes. The physical disruption, including leakage of lysosomal hydrolases into the cytosol, led to programmed cell death and necrosis. Our work provides a novel strategy of designing magnetic nanomedicines for mechanical destruction of cancer cells. PMID:28529648

Effects of current on droplet generation and arc plasma in gas metal arc welding

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

Hu, J.; Tsai, H. L.

2006-09-01

In gas metal arc welding (GMAW), a technology using pulsed currents has been employed to achieve the one-droplet-per-pulse (ODPP) metal transfer mode with the advantages of low average currents, a stable and controllable droplet generation, and reduced spatter. In this paper, a comprehensive model was developed to study the effects of different current profiles on the droplet formation, plasma generation, metal transfer, and weld pool dynamics in GMAW. Five types of welding currents were studied, including two constant currents and three wave form currents. In each type, the transient temperature and velocity distributions of the arc plasma and the moltenmore » metal, and the shapes of the droplet and the weld pool were calculated. The results showed that a higher current generates smaller droplets, higher droplet frequency, and higher electromagnetic force that becomes the dominant factor detaching the droplet from the electrode tip. The model has demonstrated that a stable ODPP metal transfer mode can be achieved by choosing a current with proper wave form for given welding conditions.« less

Dominican Immigrants and Discrimination in a New Destination: The Case of Reading, Pennsylvania*

PubMed Central

Oropesa, R.S.; Jensen, Leif

2014-01-01

The last decade has witnessed the diversification of immigrant destinations in the United States. Although the literature on this phenomenon is burgeoning, research on the experiences of smaller immigrant groups in new destinations is underdeveloped. This is especially the case for those from the Dominican Republic, a group that is expanding beyond the traditional gateway cities of the Northeast. Using a survey of Dominican immigrants in Reading, Pennsylvania, this study has two objectives. The first objective is to describe the prevalence of experiences with institutional and interpersonal discrimination. The second objective is to determine the extent to which these experiences are structured around racial markers (i.e. skin tone), forms of capital, forms of incorporation, and exposure to the U.S. Our results show that a substantial minority of Dominican immigrants claims to have been treated unfairly, primarily because of their “race and ethnicity.” In addition, experiences with some types of discrimination are positively associated with skin tone (i.e., darkness) and several factors that are identified in models of assimilation. PMID:25506273

Establishing Evidence for Internal Structure Using Exploratory Factor Analysis

ERIC Educational Resources Information Center

Watson, Joshua C.

2017-01-01

Exploratory factor analysis (EFA) is a data reduction technique used to condense data into smaller sets of summary variables by identifying underlying factors potentially accounting for patterns of collinearity among said variables. Using an illustrative example, the 5 general steps of EFA are described with best practices for decision making…

New polymorphs of 9-nitro-camptothecin prepared using a supercritical anti-solvent process.

PubMed

Huang, Yinxia; Wang, Hongdi; Liu, Guijin; Jiang, Yanbin

2015-12-30

Recrystallization and micronization of 9-nitro-camptothecin (9-NC) has been investigated using the supercritical anti-solvent (SAS) technology in this study. Five operating factors, i.e., the type of organic solvent, the concentration of 9-NC in the solution, the flow rate of 9-NC solution, the precipitation pressure and the temperature, were optimized using a selected OA16 (4(5)) orthogonal array design and a series of characterizations were performed for all samples. The results showed that the processed 9-NC particles exhibited smaller particle size and narrower particle size distribution as compared with 9-NC raw material (Form I), and the optimum micronization conditions for preparing 9-NC with minimum particle size were determined by variance analysis, where the solvent plays the most important role in the formation and transformation of polymorphs. Three new polymorphic forms (Form II, III and IV) of 9-NC, which present different physicochemical properties, were generated after the SAS process. The predicted structures of the 9-NC crystals, which were consistent with the experiments, were performed from their experimental XRD data by the direct space approach using the Reflex module of Materials Studio. Meanwhile, the optimal sample (Form III) was proved to have higher cytotoxicity against the cancer cells, which suggested the therapeutic efficacy of 9-NC is polymorph-dependent. Copyright © 2015 Elsevier B.V. All rights reserved.

Geology of five small Australian impact craters

USGS Publications Warehouse

Shoemaker, E.M.; Macdonald, F.A.; Shoemaker, C.S.

2005-01-01

Here we present detailed geological maps and cross-sections of Liverpool, Wolfe Creek, Boxhole, Veevers and Dalgaranga craters. Liverpool crater and Wolfe Creek Meteorite Crater are classic bowlshaped, Barringer-type craters, Liverpool was likely formed during the Neoproterozoic and was filled and covered with sediments soon thereafter. In the Cenozoic, this cover was exhumed exposing the crater's brecciated wall rocks. Wolfe Creek Meteorite Crater displays many striking features, including well-bedded ejecta units, crater-floor faults and sinkholes, a ringed aeromagnetic anomaly, rim-skirting dunes, and numerous iron-rich shale balls. Boxhole Meteorite Crater, Veevers Meteorite Crater and Dalgaranga crater are smaller, Odessa-type craters without fully developed, steep, overturned rims. Boxhole and Dalgaranga craters are developed in highly follated Precambrian basement rocks with a veneer of Holocene colluvium. The pre-existing structure at these two sites complicates structural analyses of the craters, and may have influenced target deformation during impact. Veevers Meteorite Crater is formed in Cenozoic laterites, and is one of the best-preserved impact craters on Earth. The craters discussed herein were formed in different target materials, ranging from crystalline rocks to loosely consolidated sediments, containing evidence that the impactors struck at an array of angles and velocities. This facilitates a comparative study of the influence of these factors on the structural and topographic form of small impact craters. ?? Geological Society of Australia.

Methodology for Sensitivity Analysis, Approximate Analysis, and Design Optimization in CFD for Multidisciplinary Applications

NASA Technical Reports Server (NTRS)

Taylor, Arthur C., III; Hou, Gene W.

1996-01-01

An incremental iterative formulation together with the well-known spatially split approximate-factorization algorithm, is presented for solving the large, sparse systems of linear equations that are associated with aerodynamic sensitivity analysis. This formulation is also known as the 'delta' or 'correction' form. For the smaller two dimensional problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. However, iterative methods are needed for larger two-dimensional and three dimensional applications because direct methods require more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioned coefficient matrix; this problem is overcome when these equations are cast in the incremental form. The methodology is successfully implemented and tested using an upwind cell-centered finite-volume formulation applied in two dimensions to the thin-layer Navier-Stokes equations for external flow over an airfoil. In three dimensions this methodology is demonstrated with a marching-solution algorithm for the Euler equations to calculate supersonic flow over the High-Speed Civil Transport configuration (HSCT 24E). The sensitivity derivatives obtained with the incremental iterative method from a marching Euler code are used in a design-improvement study of the HSCT configuration that involves thickness. camber, and planform design variables.

Thermal experience during embryogenesis contributes to the induction of dwarfism in whitefish Coregonus lavaretus.

PubMed

Steinbacher, Peter; Wanzenböck, Josef; Brandauer, Magdalena; Holper, Raphael; Landertshammer, Jasmin; Mayr, Magdalena; Platzl, Christian; Stoiber, Walter

2017-01-01

Ecotype pairs provide well-suited model systems for study of intraspecific phenotypical diversification of animals. However, little is still known about the processes that account for the development of different forms and sizes within a species, particularly in teleosts. Here, embryos of a normal-growing 'large' form and a dwarf form of whitefish Coregonus lavaretus were incubated at two temperatures that are usually experienced at their own spawning sites (2°C for the normal and 6°C for the dwarf form). All fish were subjected to similar thermal treatment after hatching. The present data demonstrate for the first time that different thermal experience in embryonic life has lasting effects on body and muscle growth of this ecotype pair and contributes to the development of the dwarf form. Thus, juvenile fish of the regular form are much smaller and have less muscle mass when pre-hatching thermal conditions were similar to those typical for the spawning sites of the dwarf form (6°C) than when subjected to conditions of their own spawning sites (2°C). Surprisingly, fish of the dwarf form exhibit a similar pattern of response to thermal history (2°-fish much larger than 6°-fish), indicating that in their case, normal spawning site temperature (6°C) is indeed likely to act as a growth limiting factor. Results also demonstrate that the hypertrophic and hyperplastic muscle growth modes are similarly affected by thermal history. Immunolabelling experiments for Pax7, H3P and Mef2 provide evidence that the cellular mechanisms behind the increased growth rates after cold incubation in both ecotypes are increased proliferation and reduced differentiation rates of muscle precursor cells. This is of major significance to aspects of ecological and developmental biology and from the evolutionary perspective.

Development of Solar Grade Silicon (SoG-Si) Feedstock by Recycling SoG-Si Wastes

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

Lifeng Zhang; Anping Dong; Lucas Nana Wiredu Damoah

2013-01-24

Experiment results of EM separation show that the non-metallic inclusions were successfully pushed to the boundary layer of the crucible under EM force. Larger frequency and smaller current generate smaller thickness of accumulated inclusions. More detailed EM separation experiments are undergoing to investigate the factors that affect the removal efficient of inclusions from SoG-Si

Effect of component substitution on the atomic dynamics in glass-forming binary metallic melts

NASA Astrophysics Data System (ADS)

Nowak, B.; Holland-Moritz, D.; Yang, F.; Voigtmann, Th.; Evenson, Z.; Hansen, T. C.; Meyer, A.

2017-08-01

We investigate the substitution of early transition metals (Zr, Hf, and Nb) in Ni-based binary glass-forming metallic melts and the impact on structural and dynamical properties by using a combination of neutron scattering, electrostatic levitation (ESL), and isotopic substitution. The self-diffusion coefficients measured by quasielastic neutron scattering (QENS) identify a sluggish diffusion as well as an increased activation energy by almost a factor of 2 for Hf35Ni65 compared to Zr36Ni64 . This finding can be explained by the locally higher packing density of Hf atoms in Hf35Ni65 compared to Zr atoms in Zr36Ni64 , which has been derived from interatomic distances by analyzing the measured partial structure factors. Furthermore, QENS measurements of liquid Hf35Ni65 prepared with 60Ni , which has a vanishing incoherent scattering cross section, have demonstrated that self-diffusion of Hf is slowed down compared to the concentration weighted self-diffusion of Hf and Ni. This implies a dynamical decoupling between larger Hf and smaller Ni atoms, which can be related to a saturation effect of unequal atomic nearest-neighbor pairs, that was observed recently for Ni-rich compositions in Zr-Ni metallic melts. In order to establish a structure-dynamics relation, measured partial structure factors have been used as an input for mode-coupling theory (MCT) of the glass transition to calculate self-diffusion coefficients for the different atomic components. Remarkably, MCT can reproduce the increased activation energy for Hf35Ni65 as well as the dynamical decoupling between Hf and Ni atoms.

Benzothiadiazole-based polymer for single and double junction solar cells with high open circuit voltage.

PubMed

Venkatesan, Swaminathan; Ngo, Evan C; Chen, Qiliang; Dubey, Ashish; Mohammad, Lal; Adhikari, Nirmal; Mitul, Abu Farzan; Qiao, Qiquan

2014-06-21

Single and double junction solar cells with high open circuit voltage were fabricated using poly{thiophene-2,5-diyl-alt-[5,6-bis(dodecyloxy)benzo[c][1,2,5]thiadiazole]-4,7-diyl} (PBT-T1) blended with fullerene derivatives in different weight ratios. The role of fullerene loading on structural and morphological changes was investigated using atomic force microscopy (AFM) and X-ray diffraction (XRD). The XRD and AFM measurements showed that a higher fullerene mixing ratio led to breaking of inter-chain packing and hence resulted in smaller disordered polymer domains. When the PBT-T1:PC60BM weight ratio was 1 : 1, the polymer retained its structural order; however, large aggregated domains formed, leading to poor device performance due to low fill factor and short circuit current density. When the ratio was increased to 1 : 2 and then 1 : 3, smaller amorphous domains were observed, which improved photovoltaic performance. The 1 : 2 blending ratio was optimal due to adequate charge transport pathways giving rise to moderate short circuit current density and fill factor. Adding 1,8-diiodooctane (DIO) additive into the 1 : 2 blend films further improved both the short circuit current density and fill factor, leading to an increased efficiency to 4.5% with PC60BM and 5.65% with PC70BM. These single junction solar cells exhibited a high open circuit voltage at ∼ 0.9 V. Photo-charge extraction by linearly increasing voltage (Photo-CELIV) measurements showed the highest charge carrier mobility in the 1 : 2 film among the three ratios, which was further enhanced by introducing the DIO. The Photo-CELIV measurements with varying delay times showed significantly higher extracted charge carrier density for cells processed with DIO. Tandem devices using P3HT:IC60BA as bottom cell and PBT-T1:PC60BM as top cell exhibited a high open circuit voltage of 1.62 V with 5.2% power conversion efficiency.

Accessibility and use of primary healthcare for immigrants living in the Niagara Region.

PubMed

Lum, Irene D; Swartz, Rebecca H; Kwan, Matthew Y W

2016-05-01

Although the challenges of accessing and using primary healthcare for new immigrants to Canada have been fairly well documented, the focus has primarily been on large cities with significant immigrant populations. The experiences of immigrants living in smaller, less diverse urban centres remain largely unknown. The purpose of this study was to examine the lived experiences of immigrants living in a small urban centre with regards to the primary healthcare system. A total of 13 immigrants living in the Greater Niagara Region participated in semi-structured interviews. All interviews were recorded, transcribed, and then coded and analyzed for emergent themes using NVivo. Five factors were found to impact primary care access and use: lack of social contacts, lack of universal healthcare coverage during their initial arrival, language as a barrier, treatment preferences, and geographic distance to primary care. Overall findings suggest that immigrants moving to smaller areas such as the Niagara Region face similar barriers to primary care as those moving into large cities. Some barriers, however, appear to be specific to the context of smaller urban centres, further exacerbated by living in a small city due to a smaller immigrant population, fewer services for immigrants, and less diversity in practicing physicians. More research is required to understand the contextual factors inhibiting primary care access and use among immigrants moving to smaller urban centres, and determine effective strategies to overcome these barriers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Can computed crystal energy landscapes help understand pharmaceutical solids?

PubMed Central

Price, Sarah L.; Braun, Doris E.; Reutzel-Edens, Susan M.

2017-01-01

Computational crystal structure prediction (CSP) methods can now be applied to the smaller pharmaceutical molecules currently in drug development. We review the recent uses of computed crystal energy landscapes for pharmaceuticals, concentrating on examples where they have been used in collaboration with industrial-style experimental solid form screening. There is a strong complementarity in aiding experiment to find and characterise practically important solid forms and understanding the nature of the solid form landscape. PMID:27067116

Heat pipe with improved wick structures

DOEpatents

Benson, David A.; Robino, Charles V.; Palmer, David W.; Kravitz, Stanley H.

2000-01-01

An improved planar heat pipe wick structure having projections formed by micromachining processes. The projections form arrays of interlocking, semi-closed structures with multiple flow paths on the substrate. The projections also include overhanging caps at their tops to increase the capillary pumping action of the wick structure. The capped projections can be formed in stacked layers. Another layer of smaller, more closely spaced projections without caps can also be formed on the substrate in between the capped projections. Inexpensive materials such as Kovar can be used as substrates, and the projections can be formed by electrodepositing nickel through photoresist masks.

Size effects in tin-based lead-free solder joints: Kinetics of bond formation and mechanical characteristics

NASA Astrophysics Data System (ADS)

Abdelhadi, Ousama Mohamed Omer

Continuous miniaturization of microelectronic interconnects demands smaller joints with comparable microstructural and structural sizes. As the size of joints become smaller, the volume of intermetallics (IMCs) becomes comparable with the joint size. As a result, the kinetics of bond formation changes and the types and thicknesses of IMC phases that form within the constrained region of the bond varies. This dissertation focuses on investigating combination effects of process parameters and size on kinetics of bond formation, resulting microstructure and the mechanical properties of joints that are formed under structurally constrained conditions. An experiment is designed where several process parameters such as time of bonding, temperature, and pressure, and bond thickness as structural chracteristic, are varied at multiple levels. The experiment is then implemented on the process. Scanning electron microscope (SEM) is then utilized to determine the bond thickness, IMC phases and their thicknesses, and morphology of the bonds. Electron backscatter diffraction (EBSD) is used to determine the grain size in different regions, including the bulk solder, and different IMC phases. Physics-based analytical models have been developed for growth kinetics of IMC compounds and are verified using the experimental results. Nanoindentation is used to determine the mechanical behavior of IMC phases in joints in different scales. Four-point bending notched multilayer specimen and four-point bending technique were used to determine fracture toughness of the bonds containing IMCs. Analytical modeling of peeling and shear stresses and fracture toughness in tri-layer four-point bend specimen containing intermetallic layer was developed and was verified and validated using finite element simulation and experimental results. The experiment is used in conjunction with the model to calculate and verify the fracture toughness of Cu6Sn5 IMC materials. As expected two different IMC phases, η-phase (Cu6Sn 5) and epsilon-phase (Cu3Sn), were found in almost all the cases regardless of the process parameters and size levels. The physics-based analytical model was successfully able to capture the governing mechanisms of IMC growth: chemical reaction controlled and diffusion-controlled. Examination of microstructures of solder joints of different sizes revealed the size of the solder joint has no effect on the type of IMCs formed during the process. Joint size, however, affected the thickness of IMC layers significantly. IMC layers formed in the solder joints of smaller sizes were found to be thicker than those in the solder joints of larger sizes. The growth rate constants and activation energies of Cu3Sn IMC layer were also reported and related to joint thickness. In an effort to optimize the EBSD imaging in the multi-layer configuration, an improved specimen preparation technique and optimum software parameters were determined. Nanoindentation results show that size effects play a major role on the mechanical properties of micro-scale solder joints. Smaller joints show higher Young's modulus, hardness, and yield strength and lower work hardening exponents comparing to thicker joints. To obtain the stress concentration factors in a multilayer specimen with IMC layer as bonding material, a four-point bending notched configuration was used. The analytical solutions developed for peeling and shear stresses in notched structure were used to evaluate the stresses at IMC interface layers. Results were in good agreement with the finite-element simulation. The values of interfacial stresses were utilized in obtaining fracture toughness of the IMC material. (Abstract shortened by UMI.)

Population attribute compression

DOEpatents

White, James M.; Faber, Vance; Saltzman, Jeffrey S.

1995-01-01

An image population having a large number of attributes is processed to form a display population with a predetermined smaller number of attributes that represent the larger number of attributes. In a particular application, the color values in an image are compressed for storage in a discrete look-up table (LUT). Color space containing the LUT color values is successively subdivided into smaller volumes until a plurality of volumes are formed, each having no more than a preselected maximum number of color values. Image pixel color values can then be rapidly placed in a volume with only a relatively few LUT values from which a nearest neighbor is selected. Image color values are assigned 8 bit pointers to their closest LUT value whereby data processing requires only the 8 bit pointer value to provide 24 bit color values from the LUT.

Precise MS light-quark masses from lattice QCD in the regularization invariant symmetric momentum-subtraction scheme

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

Gorbahn, Martin; Jaeger, Sebastian; Department of Physics and Astronomy, University of Sussex, Falmer, Brighton BN1 9QH

2010-12-01

We compute the conversion factors needed to obtain the MS and renormalization-group-invariant (RGI) up, down, and strange quark masses at next-to-next-to-leading order from the corresponding parameters renormalized in the recently proposed RI/SMOM and RI/SMOM{sub {gamma}{sub {mu}} }renormalization schemes. This is important for obtaining the MS masses with the best possible precision from numerical lattice QCD simulations, because the customary RI{sup (')}/MOM scheme is afflicted with large irreducible uncertainties both on the lattice and in perturbation theory. We find that the smallness of the known one-loop matching coefficients is accompanied by even smaller two-loop contributions. From a study of residual scalemore » dependences, we estimate the resulting perturbative uncertainty on the light-quark masses to be about 2% in the RI/SMOM scheme and about 3% in the RI/SMOM{sub {gamma}{sub {mu}} }scheme. Our conversion factors are given in fully analytic form, for general covariant gauge and renormalization point. We provide expressions for the associated anomalous dimensions.« less

Surface-based morphometry reveals the neuroanatomical basis of the five-factor model of personality

PubMed Central

Riccelli, Roberta; Toschi, Nicola; Nigro, Salvatore; Terracciano, Antonio

2017-01-01

Abstract The five-factor model (FFM) is a widely used taxonomy of human personality; yet its neuro anatomical basis remains unclear. This is partly because past associations between gray-matter volume and FFM were driven by different surface-based morphometry (SBM) indices (i.e. cortical thickness, surface area, cortical folding or any combination of them). To overcome this limitation, we used Free-Surfer to study how variability in SBM measures was related to the FFM in n = 507 participants from the Human Connectome Project. Neuroticism was associated with thicker cortex and smaller area and folding in prefrontal–temporal regions. Extraversion was linked to thicker pre-cuneus and smaller superior temporal cortex area. Openness was linked to thinner cortex and greater area and folding in prefrontal–parietal regions. Agreeableness was correlated to thinner prefrontal cortex and smaller fusiform gyrus area. Conscientiousness was associated with thicker cortex and smaller area and folding in prefrontal regions. These findings demonstrate that anatomical variability in prefrontal cortices is linked to individual differences in the socio-cognitive dispositions described by the FFM. Cortical thickness and surface area/folding were inversely related each others as a function of different FFM traits (neuroticism, extraversion and consciousness vs openness), which may reflect brain maturational effects that predispose or protect against psychiatric disorders. PMID:28122961

Megalophallus deblocki n. sp. (Digenea: Microphallidae) from Rostrhamus sociabilis (Vieillot) (Aves: Accipitridae) in Paraguay.

PubMed

Kostadinova, Aneta; Vaucher, Claude; Gibson, David I

2006-02-01

A new species in the little-known digenean fauna of Paraguayan birds is described in detail, especially in relation to its terminal genitalia. The new form, Megalophallus deblocki n. sp., is a microphallid from the intestine of the snail kite Rostrhamus sociabilis (Vieillot). It is differentiated in detail from its congeners, but differs mainly in having a substantially larger phallus (e.g. in relation to the ventral sucker), a smaller ventral sucker and smaller eggs. Comments are included on the functional morphology of the terminal genitalia.

In-situ, Gate Bias Dependent Study of Neutron Irradiation Effects on AlGaN/GaN HFETs

DTIC Science & Technology

2010-03-01

band gap and high breakdown field, AlGaN devices can operate at very high temperature and operating frequency. AlGaN/GaN based structures, have been...stable under ambient conditions [3]. GaN has a wide, direct band gap of 3.4 eV. It is therefore suitable for high temperature devices. Its high...also be grown with a wurtzite crystal structure and has a band - gap of 6.1 eV. Aluminum, due to having smaller atoms than gallium, forms a smaller

On the Distribution of Free Path Lengthsfor the Periodic Lorentz Gas

NASA Astrophysics Data System (ADS)

Bourgain, Jean; Golse, François; Wennberg, Bernt

Consider the domain and let the free path length be defined as The distribution of values of is studied in the limit as for all . It is shown that the value is critical for this problem: in other words, the limiting behavior of depends only on whether γ is larger or smaller than .

Influence of the hydrogen-bond interactions on the excited-state dynamics of a push-pull azobenzene dye: the case of Methyl Orange.

PubMed

Nançoz, Christoph; Licari, Giuseppe; Beckwith, Joseph S; Soederberg, Magnus; Dereka, Bogdan; Rosspeintner, Arnulf; Yushchenko, Oleksandr; Letrun, Romain; Richert, Sabine; Lang, Bernhard; Vauthey, Eric

2018-03-07

The excited-state dynamics of the push-pull azobenzene Methyl Orange (MO) were investigated in several solvents and water/glycerol mixtures using a combination of ultrafast time-resolved fluorescence and transient absorption in both the UV-visible and the IR regions, as well as quantum chemical calculations. Optical excitation of MO in its trans form results in the population of the S 2 ππ* state and is followed by internal conversion to the S 1 nπ* state in ∼50 fs. The population of this state decays on the sub-picosecond timescale by both internal conversion to the trans ground state and isomerisation to the cis ground state. Finally, the cis form converts thermally to the trans form on a timescale ranging from less than 50 ms to several minutes. Significant differences depending on the hydrogen-bond donor strength of the solvents, quantified by the Kamlet Taft parameter α, were observed: compared to the other solvents, in highly protic solvents (α > 1), (i) the viscosity dependence of the S 1 state lifetime is less pronounced, (ii) the S 1 state lifetime is shorter by a factor of ≈1.5 for the same viscosity, (iii) the trans-to-cis photoisomerisation efficiency is smaller, and (iv) the thermal cis-to-trans isomerisation is faster by a factor of ≥10 3 . These differences are explained in terms of hydrogen-bond interactions between the solvent and the azo nitrogen atoms of MO, which not only change the nature of the S 1 state but also have an impact on the shape of ground- and excited-state potentials, and, thus, affect the deactivation pathways from the excited state.

Orbitofrontal Cortex Volume and Effortful Control as Prospective Risk Factors for Substance Use Disorder in Adolescence.

PubMed

Cheetham, Ali; Allen, Nicholas B; Whittle, Sarah; Simmons, Julian; Yücel, Murat; Lubman, Dan I

2017-01-01

Orbitofrontal cortex (OFC) dysfunction has been proposed to increase the risk for developing a substance use disorder (SUD) during adolescence. In this study, we suggest that a reduction in OFC volumes might underlie temperament-based risk factors for SUD, and examined whether smaller OFC volumes during early adolescence could predict later development of SUD. Adolescents (n = 107; 58 male, 49 female) underwent structural MRI and completed a self-report measure of temperamental effortful control at age 12. At 3 subsequent assessments (aged 15, 16, and 18) SUD was assessed via a semi-structured clinical interview. By the third assessment, 24 participants (22.4%) had received a lifetime diagnosis of SUD. Smaller volumes of the left OFC, right OFC, and left medial subregions predicted lifetime history of SUD by age 18. Volumes of the left OFC and left lateral subregions were positively correlated with effortful control, and left OFC volumes mediated the relationship between effortful control and SUD. Smaller volumes of the OFC and low effortful control during adolescence appear to be associated phenotypes that increase the risk of subsequent SUD. Further studies examining the temporal sequence of these risk factors are needed to fully understand this relationship. © 2016 S. Karger AG, Basel.

Beam wander and M2-factor of partially coherent electromagnetic hollow Gaussian beam propagating through non-Kolmogorov turbulence

NASA Astrophysics Data System (ADS)

Xu, Yonggen; Tian, Huanhuan; Dan, Youquan; Feng, Hao; Wang, Shijian

2017-04-01

Propagation formulae for M2-factor and beam wander of partially coherent electromagnetic hollow Gaussian (PCEHG) beam in non-Kolmogorov turbulence are derived based on the extended Huygens-Fresnel principle and the second-order moments of the Wigner distribution function. Our results indicate that the normalized M2-factors of PCEHG beam with larger beam order, waist width, inner scale of turbulence, the generalized exponent parameter, and smaller transverse coherent widths, outer scale of turbulence, the generalized structure parameter are less affected by the turbulence. The root mean square beam wander and relative beam wander are more obvious for PCEHG beam with smaller beam order, larger inner and outer scales of turbulence, exponent parameter, transverse coherent widths, and the generalized structure parameter. What is more, the beam wander properties of PCEHG beam in non-Kolmogorov turbulence are very different from M2-factor and spreading properties of beam in turbulence.

Forming an ad-hoc nearby storage, based on IKAROS and social networking services

NASA Astrophysics Data System (ADS)

Filippidis, Christos; Cotronis, Yiannis; Markou, Christos

2014-06-01

We present an ad-hoc "nearby" storage, based on IKAROS and social networking services, such as Facebook. By design, IKAROS is capable to increase or decrease the number of nodes of the I/O system instance on the fly, without bringing everything down or losing data. IKAROS is capable to decide the file partition distribution schema, by taking on account requests from the user or an application, as well as a domain or a Virtual Organization policy. In this way, it is possible to form multiple instances of smaller capacity higher bandwidth storage utilities capable to respond in an ad-hoc manner. This approach, focusing on flexibility, can scale both up and down and so can provide more cost effective infrastructures for both large scale and smaller size systems. A set of experiments is performed comparing IKAROS with PVFS2 by using multiple clients requests under HPC IOR benchmark and MPICH2.

Time-dependent analysis of incidence, risk factors and clinical significance of pneumothorax after percutaneous lung biopsy.

PubMed

Lim, Woo Hyeon; Park, Chang Min; Yoon, Soon Ho; Lim, Hyun-Ju; Hwang, Eui Jin; Lee, Jong Hyuk; Goo, Jin Mo

2018-03-01

To evaluate the time-dependent incidence, risk factors and clinical significance of percutaneous lung biopsy (PLB)-related pneumothorax. From January 2012-November 2015, 3,251 patients underwent 3,354 cone-beam CT-guided PLBs for lung lesions. Cox, logistic and linear regression analyses were performed to identify time-dependent risk factors of PLB-related pneumothorax, risk factors of drainage catheter insertion and those of prolonged catheter placement, respectively. Pneumothorax occurred in 915/3,354 PLBs (27.3 %), with 230/915 (25.1 %) occurring during follow-ups. Risk factors for earlier occurrence of PLB-related pneumothorax include emphysema (HR=1.624), smaller target (HR=0.922), deeper location (HR=1.175) and longer puncture time (HR=1.036), while haemoptysis (HR=0.503) showed a protective effect against earlier development of pneumothorax. Seventy-five cases (8.2 %) underwent chest catheter placement. Mean duration of catheter placement was 3.2±2.0 days. Emphysema (odds ratio [OR]=2.400) and longer puncture time (OR=1.053) were assessed as significant risk factors for catheter insertion, and older age (parameter estimate=1.014) was a predictive factor for prolonged catheter placement. PLB-related pneumothorax occurred in 27.3 %, of which 25.1 % developed during follow-ups. Smaller target size, emphysema, deeply-located lesions were significant risk factors of PLB-related pneumothorax. Emphysema and older age were related to drainage catheter insertion and prolonged catheter placement, respectively. • One-fourth of percutaneous lung biopsy (PLB)-related pneumothorax occurs during follow-up. • Smaller, deeply-located target and emphysema lead to early occurrence of pneumothorax. • Emphysema is related to drainage catheter insertion for PLB-related pneumothorax. • Older age may lead to prolonged catheter placement for PLB-related pneumothorax. • Tailored management can be possible with time-dependent information of PLB-related pneumothorax.

Migration of icy planetesimals to forming terrestrial planets

NASA Astrophysics Data System (ADS)

Ipatov, Sergei I.; Marov, Mikhail

2016-07-01

Our studies of migration of planetesimals from the feeding zone of Jupiter and Saturn to forming terrestrial planets were based on computer simulations of the orbital evolution of 10^4 planetesimals under the gravitational influence of planets. In series JN, all planets were considered in present orbits with present masses, and in series JS, Uranus and Neptune were excluded. Initial eccentricities and inclinations of planetesimals were 0.3 and 0.15 rad, respectively. Their initial semi-major axes were between 4.5 and 12 AU. Masses of planets moving in the orbits of the terrestrial planets were equal to present masses of the planets in series JS and JN, and were smaller by a factor of 10 in series JS_{01} and JN_{01}. The obtained results show that the ratio of the fraction of the planetesimals collided with an embryo of the Earth's embryo was about 2\\cdot10^{-6} and 4\\cdot10^{-7} for the mass of the embryo equal to the Earth mass and to 10% of the Earth mass, respectively. We concluded that during the growth of the mass of the Earth's embryo up to a half of the present mass of the Earth, the amount of water delivered to the embryo could be about 30% of all water delivered to the Earth from the feeding zone of Jupiter and Saturn. The total mass of water delivered to the Earth from the feeding zones of the giant planets and beyond these zones could be comparable with the mass of the Earth's oceans. A half of this water could come from the feeding zone of Jupiter and Saturn, and another half from more distant regions. Most of the water that was delivered from the distant regions to the Earth's embryo came when its mass was not small (e.g., was mainly greater than a half of the Earth mass). In series JS, the ratio of the mass of water delivered to a planet to the mass of the planet for the Earth was smaller by a factor of 2, 1.25, and 1.3 than for Mars, Venus and Mercury, respectively. For series JN, the above values of the factor were equal to 3.4, 0.7 i 0.8. For the growth of the Earth's embryo of mass m by accretion of planetesimals that came from the feeding zone of Jupiter and Saturn, the increase of its mass was proportional to m^{0.74}.

Photocatalytic Coatings for Exploration and Spaceport Design

NASA Technical Reports Server (NTRS)

2008-01-01

This project developed self-cleaning photocatalytic coatings that remove contamination without human intervention. The coatings chemically remove organic contaminants and leave no residue. The photocatalyst will not negatively affect other coating properties, especially corrosion resistance. Titanium dioxide, TiO2, is an extremely popular photocatalyst because of its chemical stability, nontoxicity, and low cost. TiO2 is commonly used in the photocatalytic oxidation of organic matter or pollutants in the gas and liquid phases. However, TiO2 does have some drawbacks. It has limited light absorption because of its large band-gap and suffers from a photonic efficiency of less than 10 percent for organic degradation. Dopants can lower the band-gap and improve efficiency. Since the photocatalytically active form of TiO2 is a nanocrystalline powder, it can be difficult to make a robust coating with enough catalyst loading to be effective. Photocatalysts become active when certain light energy is absorbed. When photons with an energy greater than the band-gap, Eg, (wavelengths shorter than 400 nm) impinge upon the surface of the TiO2, an electron-hole pair is formed. The electron-hole pair oxidizes adsorbed substances either directly or via reactive intermediates that form on the surface, such as hydroxyl radicals (OH) or superoxide ions (O2-). Several factors can influence the band-gap energy of TiO2, two of which are crystal structure and impurities. TiO2 exists as three crystal structures brookite, anatase, and rutile that can be controlled via heat treatment. Anatase is the most photocatalytically active crystal form of TiO2. Doping TiO2 with impurities can alter its band-gap energy, as well as its effectiveness as a catalyst. Depending on their size, dopant atoms can occupy either the substitutional or interstitial lattice positions. Atoms that are relatively large will assume the interstitial positions and create a much greater energy disturbance in the crystal than will smaller atoms that take on the substitutional positions. This energy disturbance narrows the band-gap and thus allows photons with longer wavelengths and smaller energies (such as those in the visible-light spectrum) to create electron-hole pairs. Raman spectroscopy was performed for the purpose of determining the crystal structure and the degree of crystallinity of the TiO2 particles. Reflectance measurements indicated the wavelengths of light absorbed by the different catalysts.

Nucleation of stoichiometric compounds from liquid: Role of the kinetic factor

DOE PAGES

Song, H.; Sun, Y.; Zhang, F.; ...

2018-02-02

The nucleation rate depends on the free-energy barrier and the kinetic factor. While the role of the free energy barrier is a text-book subject, the importance of the kinetic factor is frequently underestimated. Here in this study, we applied the mean first-passage time method, to obtain the free-energy landscape and kinetic factor directly from the molecular dynamics (MD) simulations of the nucleation of the face-centered cubic (fcc) phase in the pure Ni and the B2 phases in the Ni 50Al 50 and Cu 50Zr 50 alloys. The obtained data show that while the free-energy barrier for nucleation is higher inmore » pure Ni the nucleation rate is considerably lower in the Ni 50Al 50 alloy. This result can be explained by the slow attachment kinetics in the N i 50 A l 50 alloy, which was related to the ordered nature of the B2 phase. Even smaller fraction of the antisite defects in the C u 50 Z r 50 alloy leads to such a slow attachment kinetics that the nucleation is never observed for this alloy in the course of the MD simulation. Finally, this is consistent with the experimental facts that the Cu 50Zr 50 alloy is a good glass forming alloy and the Ni 50Al 50 alloy is not. Thus the present study demonstrates that the atom attachment rate can be the critical factor that controls the nucleation process under certain conditions.« less

Nucleation of stoichiometric compounds from liquid: Role of the kinetic factor

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

Song, H.; Sun, Y.; Zhang, F.

The nucleation rate depends on the free-energy barrier and the kinetic factor. While the role of the free energy barrier is a text-book subject, the importance of the kinetic factor is frequently underestimated. Here in this study, we applied the mean first-passage time method, to obtain the free-energy landscape and kinetic factor directly from the molecular dynamics (MD) simulations of the nucleation of the face-centered cubic (fcc) phase in the pure Ni and the B2 phases in the Ni 50Al 50 and Cu 50Zr 50 alloys. The obtained data show that while the free-energy barrier for nucleation is higher inmore » pure Ni the nucleation rate is considerably lower in the Ni 50Al 50 alloy. This result can be explained by the slow attachment kinetics in the N i 50 A l 50 alloy, which was related to the ordered nature of the B2 phase. Even smaller fraction of the antisite defects in the C u 50 Z r 50 alloy leads to such a slow attachment kinetics that the nucleation is never observed for this alloy in the course of the MD simulation. Finally, this is consistent with the experimental facts that the Cu 50Zr 50 alloy is a good glass forming alloy and the Ni 50Al 50 alloy is not. Thus the present study demonstrates that the atom attachment rate can be the critical factor that controls the nucleation process under certain conditions.« less

Scalar resonances in a unitary {pi}{pi} S-wave model for D{sup +} {r_arrow} {pi}{sup+}{pi}{sup-}{pi}{sup+}.

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

Boito, D. R.; Dedonder, J.-P.; El-Bennich, B.

We propose a model for D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} decays following experimental results which indicate that the two-pion interaction in the S wave is dominated by the scalar resonances f{sub 0}(600)/{sigma} and f{sub 0}(980). The weak decay amplitude for D{sup +} {yields} R{pi}{sup +}, where R is a resonance that subsequently decays into {pi}{sup +}{pi}{sup -}, is constructed in a factorization approach. In the S wave, we implement the strong decay R {yields} {pi}{sup +}{pi}{sup -} by means of a scalar form factor. This provides a unitary description of the pion-pion interaction in the entire kinematically allowedmore » mass range m{sub {pi}{pi}}{sup 2} from threshold to about 3 GeV{sup 2}. In order to reproduce the experimental Dalitz plot for D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +}, we include contributions beyond the S wave. For the P wave, dominated by the {rho}(770){sup 0}, we use a Breit-Wigner description. Higher waves are accounted for by using the usual isobar prescription for the f{sub 2}(1270) and {rho}(1450){sup 0}. The major achievement is a good reproduction of the experimental m{sub {pi}{pi}}{sup 2} distribution, and of the partial as well as the total D{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} branching ratios. Our values are generally smaller than the experimental ones. We discuss this shortcoming and, as a by-product, we predict a value for the poorly known D {yields} {sigma} transition form factor at q{sup 2} = m{sub {pi}}{sup 2}.« less

Scalar resonances in a unitary {pi}{pi} S-wave model for D{sup +}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}

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

Boito, D. R.; Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05315-970, Sao Paulo, SP; Dedonder, J.-P.

We propose a model for D{sup +}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +} decays following experimental results which indicate that the two-pion interaction in the S wave is dominated by the scalar resonances f{sub 0}(600)/{sigma} and f{sub 0}(980). The weak decay amplitude for D{sup +}{yields}R{pi}{sup +}, where R is a resonance that subsequently decays into {pi}{sup +}{pi}{sup -}, is constructed in a factorization approach. In the S wave, we implement the strong decay R{yields}{pi}{sup +}{pi}{sup -} by means of a scalar form factor. This provides a unitary description of the pion-pion interaction in the entire kinematically allowed mass range m{sub {pi}}{sub {pi}}{sup 2}more » from threshold to about 3 GeV{sup 2}. In order to reproduce the experimental Dalitz plot for D{sup +}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}, we include contributions beyond the S wave. For the P wave, dominated by the {rho}(770){sup 0}, we use a Breit-Wigner description. Higher waves are accounted for by using the usual isobar prescription for the f{sub 2}(1270) and {rho}(1450){sup 0}. The major achievement is a good reproduction of the experimental m{sub {pi}}{sub {pi}}{sup 2} distribution, and of the partial as well as the total D{sup +}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +} branching ratios. Our values are generally smaller than the experimental ones. We discuss this shortcoming and, as a by-product, we predict a value for the poorly known D{yields}{sigma} transition form factor at q{sup 2}=m{sub {pi}}{sup 2}.« less

Do marine phytoplankton follow Bergmann's rule sensu lato?

PubMed

Sommer, Ulrich; Peter, Kalista H; Genitsaris, Savvas; Moustaka-Gouni, Maria

2017-05-01

Global warming has revitalized interest in the relationship between body size and temperature, proposed by Bergmann's rule 150 years ago, one of the oldest manifestations of a 'biogeography of traits'. We review biogeographic evidence, results from clonal cultures and recent micro- and mesocosm experiments with naturally mixed phytoplankton communities regarding the response of phytoplankton body size to temperature, either as a single factor or in combination with other factors such as grazing, nutrient limitation, and ocean acidification. Where possible, we also focus on the comparison between intraspecific size shifts and size shifts resulting from changes in species composition. Taken together, biogeographic evidence, community-level experiments and single-species experiments indicate that phytoplankton average cell sizes tend to become smaller in warmer waters, although temperature is not necessarily the proximate environmental factor driving size shifts. Indirect effects via nutrient supply and grazing are important and often dominate. In a substantial proportion of field studies, resource availability is seen as the only factor of relevance. Interspecific size effects are greater than intraspecific effects. Direct temperature effects tend to be exacerbated by indirect ones, if warming leads to intensified nutrient limitation or copepod grazing while ocean acidification tends to counteract the temperature effect on cell size in non-calcifying phytoplankton. We discuss the implications of the temperature-related size trends in a global-warming context, based on known functional traits associated with phytoplankton size. These are a higher affinity for nutrients of smaller cells, highest maximal growth rates of moderately small phytoplankton (ca. 10 2  µm 3 ), size-related sensitivities for different types of grazers, and impacts on sinking rates. For a phytoplankton community increasingly dominated by smaller algae we predict that: (i) a higher proportion of primary production will be respired within the microbial food web; (ii) a smaller share of primary production will be channeled to the classic phytoplankton - crustacean zooplankton - fish food chain, thus leading to decreased ecological efficiency from a fish-production point of view; (iii) a smaller share of primary production will be exported through sedimentation, thus leading to decreased efficiency of the biological carbon pump. © 2016 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.

Method for obtaining structure and interactions from oriented lipid bilayers

PubMed Central

Lyatskaya, Yulia; Liu, Yufeng; Tristram-Nagle, Stephanie; Katsaras, John; Nagle, John F.

2009-01-01

Precise calculations are made of the scattering intensity I(q) from an oriented stack of lipid bilayers using a realistic model of fluctuations. The quantities of interest include the bilayer bending modulus Kc , the interbilayer interaction modulus B, and bilayer structure through the form factor F(qz). It is shown how Kc and B may be obtained from data at large qz where fluctuations dominate. Good estimates of F(qz) can be made over wide ranges of qz by using I(q) in q regions away from the peaks and for qr≠0 where details of the scattering domains play little role. Rough estimates of domain sizes can also be made from smaller qz data. Results are presented for data taken on fully hydrated, oriented DOPC bilayers in the Lα phase. These results illustrate the advantages of oriented samples compared to powder samples. PMID:11304287

Risk Tradeoffs in Adaptive Ecosystem Management: The Case of the U.S. Forest Service

NASA Astrophysics Data System (ADS)

Stern, Marc J.; Martin, Caysie A.; Predmore, S. Andrew; Morse, Wayde C.

2014-06-01

Natural resource planning processes on public lands in the United States are driven in large part by the requirements of the National Environmental Policy Act (NEPA), which dictates general processes for analyzing and disclosing the likely impacts of proposed actions. The outcomes of these processes are the result of multiple factors, many related to the manifold smaller incremental decisions made by agency personnel directing the processes. Through interviews with decision makers, team leaders, and team members on five NEPA processes within the U.S. Forest Service, this study examines those incremental decisions. Risk, in particular external relationship risk, emerged as a dominant lens through which agency personnel weigh and make process-related decisions. We discuss the tradeoffs associated with agency actors' emphasis on this form of risk and their potential implications for adaptive ecosystem management and organizational performance.

The Effect of a Pre-Lens Aperture on the Temperature Range and Image Uniformity of Microbolometer Infrared Cameras

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

Dinwiddie, Ralph Barton; Parris, Larkin S.; Lindal, John M.

This paper explores the temperature range extension of long-wavelength infrared (LWIR) cameras by placing an aperture in front of the lens. An aperture smaller than the lens will reduce the radiance to the sensor, allowing the camera to image targets much hotter than typically allowable. These higher temperatures were accurately determined after developing a correction factor which was applied to the built-in temperature calibration. The relationship between aperture diameter and temperature range is linear. The effect of pre-lens apertures on the image uniformity is a form of anti-vignetting, meaning the corners appear brighter (hotter) than the rest of the image.more » An example of using this technique to measure temperatures of high melting point polymers during 3D printing provide valuable information of the time required for the weld-line temperature to fall below the glass transition temperature.« less

Factors modulating the effect of divided attention during retrieval of words.

PubMed

Fernandes, Myra A; Moscovitch, Morris

2002-07-01

In this study, we examined variables modulating interference effects on episodic memory under divided attention conditions during retrieval for a list of unrelated words. In Experiment 1, we found that distracting tasks that required animacy or syllable decisions to visually presented words, without a memory load, produced large interference on free recall performance. In Experiment 2, a distracting task requiring phonemic decisions about nonsense words produced a far larger interference effect than one that required semantic decisions about pictures. In Experiment 3, we replicated the effect of the nonsense-word distracting task on memory and showed that an equally resource-demanding picture-based task produced significant interference with memory retrieval, although the effect was smaller in magnitude. Taken together, the results suggest that free recall is disrupted by competition for phonological or word-form representations during retrieval and, to a lesser extent, by competition for semantic representations.

Effects of task constraints on reaching kinematics by healthy adults.

PubMed

Wu, Ching-Yi; Lin, Keh-Chung; Lin, Kwan-Hwa; Chang, Chein-Wei; Chen, Chia-Ling

2005-06-01

Understanding the control of movement requires an awareness of how tasks constrain movements. The present study investigated the effects of two types of task constraints--spatial accuracy (effector size) and target location--on reaching kinematics. 15 right-handed healthy young adults (7 men, 8 women) whose mean age was 23.6 yr. (SD=3.9 yr.) performed the ringing task under six conditions, formed by the crossing of effector size (larger vs smaller size) and target location (left, right, or a central position). Significant main effects of effector size and target location were found for peak velocity and movement time. There was a significant interaction for the percentage of time to peak velocity. The findings suggested that task constraints may modulate movement performance in specific ways. Effects of effector size might be a consequence of feedforward and feedback control, and location effects might be influenced by both biomechanical and neurological factors.

Formation of ultrathin Ni germanides: solid-phase reaction, morphology and texture

NASA Astrophysics Data System (ADS)

van Stiphout, K.; Geenen, F. A.; De Schutter, B.; Santos, N. M.; Miranda, S. M. C.; Joly, V.; Detavernier, C.; Pereira, L. M. C.; Temst, K.; Vantomme, A.

2017-11-01

The solid-phase reaction of ultrathin (⩽10 nm) Ni films with different Ge substrates (single-crystalline (1 0 0), polycrystalline, and amorphous) was studied. As thickness goes down, thin film texture becomes a dominant factor in both the film’s phase formation and morphological evolution. As a consequence, certain metastable microstructures are epitaxially stabilized on crystalline substrates, such as the ɛ-Ni5Ge3 phase or a strained NiGe crystal structure on the single-crystalline substrates. Similarly, the destabilizing effect of axiotaxial texture on the film’s morphology becomes more pronounced as film thicknesses become smaller. These effects are contrasted by the evolution of germanide films on amorphous substrates, on which neither epitaxy nor axiotaxy can form, i.e. none of the (de)stabilizing effects of texture are observed. The crystallization of such amorphous substrates however, drives the film breakup.

Mycelial abundance and other factors related to truffle productivity in Tuber melanosporum-Quercus ilex orchards.

PubMed

Suz, Laura M; Martín, María P; Oliach, Daniel; Fischer, Christine R; Colinas, Carlos

2008-08-01

Relative quantification of DNA from Tuber melanosporum mycelia was performed by conventional and real-time PCR in soil from trees in three truffle orchards of different ages to determine: (1) whether burn appearance is related to the amount of T. melanosporum mycelium in soil, and (2) whether productivity onset and truffle production are related to (a) the amount of T. melanosporum mycelium in soil, (b) tree height and diameter, (c) burn extension and (d) surface rock cover. The burn seems to appear only after a certain amount of mycelium has formed. Precociously productive trees presented higher quantities of mycelium than nonproductive trees in the productivity onset study, while highly productive trees presented less quantities of mycelium than nonproductive trees in the productivity study. Trees with high but not excessive surface rock cover showed greater truffle production. Larger trees tended to display a burn earlier than smaller trees.

Physical Properties of Human Whole Salivary Mucin:A Dynamic Light Scattering Study

NASA Astrophysics Data System (ADS)

Mahajan, Manish; Kumar, Vijay; Saraswat, Mayank; Yadav, Savita; Shukla, N. K.; Singh, T. P.

2008-04-01

Human salivary mucin, a primary mucous membrane coating glycoprotein forms the first line of defense against adverse environments, attributed to the complex formation between mucin subunits and non mucin species. Aim of the study was to emphasize the effect of pH, denaturants (guanidinum hydrochloride, urea) and detergents (CHAPS, TRITON X -100, SDS on human whole salivary mucin. Hydrodynamic size distribution was measured using DLS. It was observed that aggregation was due to increase in hydrophobic interactions, believed to be accomplished by unfolding of the protein core. Whereas, the detergents which solubilize the proteins by decreasing hydrophobicity lead to disaggregation of mucin into smaller fragments. Mucin subjected to tobacco extract and upon subsequent addition of nicotine was found to have a disaggregating effect on it, suggesting nicotine may be one of the factors responsible for the disaggregating effect of tobacco on mucin, an important carcinogenetic mechanism.

Determining team cognition from delay analysis using cross recurrence plot.

PubMed

Hajari, Nasim; Cheng, Irene; Bin Zheng; Basu, Anup

2016-08-01

Team cognition is an important factor in evaluating and determining team performance. Forming a team with good shared cognition is even more crucial for laparoscopic surgery applications. In this study, we analyzed the eye tracking data of two surgeons during a laparoscopic simulation operation, then performed Cross Recurrence Analysis (CRA) on the recorded data to study the delay behaviour for good performer and poor performer teams. Dual eye tracking data for twenty two dyad teams were recorded during a laparoscopic task and then the teams were divided into good performer and poor performer teams based on the task times. Eventually we studied the delay between two team members for good and poor performer teams. The results indicated that the good performer teams show a smaller delay comparing to poor performer teams. This study is compatible with gaze overlap analysis between team members and therefore it is a good evidence of shared cognition between team members.

Microwave background distortions from domain walls

NASA Technical Reports Server (NTRS)

Goetz, Guenter; Noetzold, Dirk

1990-01-01

Domain walls arising in a cosmic phase transition after decoupling were recently proposed as seeds for the formation of large scale structure. The distortion induced in the microwave background radiation is calculated in dependence of the wall thickness, surface density, scalar field potential, cosmic redshift and the velocity of the wall. It was found that the maximal redshift distortion for both spherical and planar walls is of the order pi G sigma H(sup -1)(sub 0), where sigma is the surface energy density and H(sup -1)(sub 0) the Hubble parameter. It was also found that, for a wall thickness smaller than the horizon, walls can be treated as infinitely thin, i.e., the redshift distortion is independent of the wall thickness and the specific form of the scalar potential. For planar walls moving with a Lorentz-factor gamma the redshift distortion is enhanced by gamma cubed.

Internship Abstract and Final Reflection

NASA Technical Reports Server (NTRS)

Sandor, Edward

2016-01-01

The primary objective for this internship is the evaluation of an embedded natural language processor (NLP) as a way to introduce voice control into future space suits. An embedded natural language processor would provide an astronaut hands-free control for making adjustments to the environment of the space suit and checking status of consumables procedures and navigation. Additionally, the use of an embedded NLP could potentially reduce crew fatigue, increase the crewmember's situational awareness during extravehicular activity (EVA) and improve the ability to focus on mission critical details. The use of an embedded NLP may be valuable for other human spaceflight applications desiring hands-free control as well. An embedded NLP is unique because it is a small device that performs language tasks, including speech recognition, which normally require powerful processors. The dedicated device could perform speech recognition locally with a smaller form-factor and lower power consumption than traditional methods.

New customizable phased array UT instrument opens door for furthering research and better industrial implementation

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

Dao, Gavin; Ginzel, Robert

2014-02-18

Phased array UT as an inspection technique in itself continues to gain wide acceptance. However, there is much room for improvement in terms of implementation of Phased Array (PA) technology for every unique NDT application across several industries (e.g. oil and petroleum, nuclear and power generation, steel manufacturing, etc.). Having full control of the phased array instrument and customizing a software solution is necessary for more seamless and efficient inspections, from setting the PA parameters, collecting data and reporting, to the final analysis. NDT researchers and academics also need a flexible and open platform to be able to control variousmore » aspects of the phased array process. A high performance instrument with advanced PA features, faster data rates, a smaller form factor, and capability to adapt to specific applications, will be discussed.« less

Structural MRI markers of brain aging early after ischemic stroke.

PubMed

Werden, Emilio; Cumming, Toby; Li, Qi; Bird, Laura; Veldsman, Michele; Pardoe, Heath R; Jackson, Graeme; Donnan, Geoffrey A; Brodtmann, Amy

2017-07-11

To examine associations between ischemic stroke, vascular risk factors, and MRI markers of brain aging. Eighty-one patients (mean age 67.5 ± 13.1 years, 31 left-sided, 61 men) with confirmed first-ever (n = 66) or recurrent (n = 15) ischemic stroke underwent 3T MRI scanning within 6 weeks of symptom onset (mean 26 ± 9 days). Age-matched controls (n = 40) completed identical testing. Multivariate regression analyses examined associations between group membership and MRI markers of brain aging (cortical thickness, total brain volume, white matter hyperintensity [WMH] volume, hippocampal volume), normalized against intracranial volume, and the effects of vascular risk factors on these relationships. First-ever stroke was associated with smaller hippocampal volume ( p = 0.025) and greater WMH volume ( p = 0.004) relative to controls. Recurrent stroke was in turn associated with smaller hippocampal volume relative to both first-ever stroke ( p = 0.017) and controls ( p = 0.001). These associations remained significant after adjustment for age, sex, education, and, in stroke patients, infarct volume. Total brain volume was not significantly smaller in first-ever stroke patients than in controls ( p = 0.056), but the association became significant after further adjustment for atrial fibrillation ( p = 0.036). Cortical thickness and brain volumes did not differ as a function of stroke type, infarct volume, or etiology. Brain structure is likely to be compromised before ischemic stroke by vascular risk factors. Smaller hippocampal and total brain volumes and increased WMH load represent proxies for underlying vascular brain injury. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

[Sap flow characteristics of Quercus liaotungensis in response to sapwood area and soil moisture in the loess hilly region, China].

PubMed

Lyu, Jin Lin; He, Qiu Yue; Yan, Mei Jie; Li, Guo Qing; Du, Sheng

2018-03-01

To examine the characteristics of sap flow in Quercus liaotungensis and their response to environmental factors under different soil moisture conditions, Granier-type thermal dissipation probes were used to measure xylem sap flow of trees with different sapwood area in a natural Q. liaotungensis forest in the loess hilly region. Solar radiation, air temperature, relative air humidity, precipitation, and soil moisture were monitored during the study period. The results showed that sap flux of Q. liaotungensis reached daily peaks earlier than solar radiation and vapor pressure deficit. The diurnal dynamics of sap flux showed a similar pattern to those of the environmental factors. Trees had larger sap flux during the period with higher soil moisture. Under the same soil moisture conditions, trees with larger diameter and sapwood areas had significantly higher sap flux than those with smaller diameter and sapwood areas. Sap flux could be fitted with vapor pressure deficit, solar radiation, and the integrated index of the two factors using exponential saturation function. Differences in the fitted curves and parameters suggested that sap flux tended to reach saturation faster under higher soil moisture. Furthermore, trees in the smaller diameter class were more sensitive to the changes of soil moisture. The ratio of daily sap flux per unit vapor pressure deficit under lower soil moisture condition to that under higher soil moisture condition was linearly correlated to sapwood area. The regressive slope in smaller diameter class was larger than that in bigger diameter class, which further indicated the higher sensitivity of trees with smaller diameter class to soil moisture. These results indicated that wider sapwood of larger diameter class provided a buffer against drought stress.

Study on glass-forming ability and hydrogen storage properties of amorphous Mg{sub 60}Ni{sub 30}La{sub 10−x}Co{sub x} (x = 0, 4) alloys

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

Lv, Peng; Wang, Zhong-min, E-mail: zmwang@guet.edu.cn; Zhang, Huai-gang

2013-12-15

Mg{sub 60}Ni{sub 30}La{sub 10−x}Co{sub x} (x = 0, 4) amorphous alloys were prepared by rapid solidification, using a melt-spinning technique. X-ray diffraction and differential scanning calorimetry analysis were employed to measure their microstructure, thermal stability and glass-forming ability, and hydrogen storage properties were studied by means of PCTPro2000. Based on differential scanning calorimetry results, their glass-forming ability and thermal stability were investigated by Kissinger method, Lasocka curves and atomic cluster model, respectively. The results indicate that glass-forming ability, thermal properties and hydrogen storage properties in the Mg-rich corner of Mg–Ni–La–Co system alloys were enhanced by Co substitution for La. Itmore » can be found that the smaller activation energy (ΔΕ) and frequency factor (υ{sub 0}), the bigger value of B (glass transition point in Lasocka curves), and higher glass-forming ability of Mg–Ni–La–Co alloys would be followed. In addition, atomic structure parameter (λ), deduced from atomic cluster model is valuable in the design of Mg–Ni–La–Co system alloys with good glass-forming ability. With an increase of Co content from 0 to 4, the hydrogen desorption capacity within 4000 s rises from 2.25 to 2.85 wt.% at 573 K. - Highlights: • Amorphous Mg{sub 60}Ni{sub 30}La{sub 10−x}Co{sub x} (x = 0 and 4) alloys were produced by melt spinning. • The GFA and hydrogen storage properties were enhanced by Co substitution for La. • With an increase of Co content, the hydrogen desorption capacity rises at 573 K.« less

Design of a stabilized, compact gimbal for space-based free space optical communications (FSOC)

NASA Astrophysics Data System (ADS)

Cline, A.; Shubert, P.; McNally, J.; Jacka, N.; Pierson, R.

2017-02-01

Data transmits via optical communications through fibers at 10's of Terabits per second. Given the recent rapid explosion for bandwidth and competing demand for radio frequency (RF) spectrum allocations among differing interests, the need for space-based free space optical communications (FSOC) systems is ever increasing. FSOC systems offer advantages of higher data rates, smaller size and weight, narrower beam divergence, and lower power than RF systems. Lightweight, small form factor, and high performance two-axis gimbals are of strong interest for satellite FSOC applications. Small gimbal and optical terminal designs are important for widespread implementation of optical communications systems; in particular, for satellite-to-satellite crosslinks where the advantages of more secure communications links (Lower Probability of Intercept (LPI)/Lower Probability of Detect (LPD)) are very important. We developed design concepts for a small gimbal focusing on the use of commercial off-the-shelf (COTS) subsystems to establish their feasible implementation against the pointing stabilization, size, weight and power (SWaP), and performance challenges. The design drivers for the gimbal were weight, the elevation and azimuth field of regards, the form factor envelope (1U CubeSats), 100 μrad pointing accuracy, and 10 degrees per second slew capability. Innovations required in this development included a continuous fiber passed through an Azimuth Fiber Wrap and Elevation Fiber Wrap, overcoming typical mechanical and stress related limitations encountered with fiber optic cable wraps. In this presentation, we describe the configuration trades and design of such a gimbal.

Refining new-physics searches in B→Dτν with lattice QCD.

PubMed

Bailey, Jon A; Bazavov, A; Bernard, C; Bouchard, C M; Detar, C; Du, Daping; El-Khadra, A X; Foley, J; Freeland, E D; Gámiz, E; Gottlieb, Steven; Heller, U M; Kim, Jongjeong; Kronfeld, A S; Laiho, J; Levkova, L; Mackenzie, P B; Meurice, Y; Neil, E T; Oktay, M B; Qiu, Si-Wei; Simone, J N; Sugar, R; Toussaint, D; Van de Water, R S; Zhou, Ran

2012-08-17

The semileptonic decay channel B→Dτν is sensitive to the presence of a scalar current, such as that mediated by a charged-Higgs boson. Recently, the BABAR experiment reported the first observation of the exclusive semileptonic decay B→Dτ(-)ν, finding an approximately 2σ disagreement with the standard-model prediction for the ratio R(D)=BR(B→Dτν)/BR(B→Dℓν), where ℓ = e,μ. We compute this ratio of branching fractions using hadronic form factors computed in unquenched lattice QCD and obtain R(D)=0.316(12)(7), where the errors are statistical and total systematic, respectively. This result is the first standard-model calculation of R(D) from ab initio full QCD. Its error is smaller than that of previous estimates, primarily due to the reduced uncertainty in the scalar form factor f(0)(q(2)). Our determination of R(D) is approximately 1σ higher than previous estimates and, thus, reduces the tension with experiment. We also compute R(D) in models with electrically charged scalar exchange, such as the type-II two-Higgs-doublet model. Once again, our result is consistent with, but approximately 1σ higher than, previous estimates for phenomenologically relevant values of the scalar coupling in the type-II model. As a by-product of our calculation, we also present the standard-model prediction for the longitudinal-polarization ratio P(L)(D)=0.325(4)(3).

Nuclear morphometry in histological specimens of canine prostate cancer: Correlation with histological subtypes, Gleason score, methods of collection and survival time.

PubMed

Di Donato, Guido; Laufer-Amorim, Renée; Palmieri, Chiara

2017-10-01

Ten normal prostates, 22 benign prostatic hyperplasia (BPH) and 29 prostate cancer (PC) were morphometrically analyzed with regard to mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear diameter (MND), coefficient of variation of the nuclear area (NACV), mean nuclear diameter maximum (MDx), mean nuclear diameter minimum (MDm), mean nuclear form ellipse (MNFe) and form factor (FF). The relationship between nuclear morphometric parameters and histological type, Gleason score, methods of sample collection, presence of metastases and survival time of canine PC were also investigated. Overall, nuclei from neoplastic cells were larger, with greater variation in nuclear size and shape compared to normal and hyperplastic cells. Significant differences were found between more (small acinar/ductal) and less (cribriform, solid) differentiated PCs with regard to FF (p<0.05). MNA, MNP, MND, MDx, and MDm were significantly correlated with the Gleason score of PC (p<0.05). MNA, MNP, MDx and MNFe may also have important prognostic implications in canine prostatic cancer since negatively correlated with the survival time. Biopsy specimens contained nuclei that were smaller and more irregular in comparison to those in prostatectomy and necropsy specimens and therefore factors associated with tissue sampling and processing may influence the overall morphometric evaluation. The results indicate that nuclear morphometric analysis in combination with Gleason score can help in canine prostate cancer grading, thus contributing to the establishment of a more precise prognosis and patient's management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Low-cost low-power uncooled a-Si-based micro infrared camera for unattended ground sensor applications

NASA Astrophysics Data System (ADS)

Schimert, Thomas R.; Ratcliff, David D.; Brady, John F., III; Ropson, Steven J.; Gooch, Roland W.; Ritchey, Bobbi; McCardel, P.; Rachels, K.; Wand, Marty; Weinstein, M.; Wynn, John

1999-07-01

Low power and low cost are primary requirements for an imaging infrared camera used in unattended ground sensor arrays. In this paper, an amorphous silicon (a-Si) microbolometer-based uncooled infrared camera technology offering a low cost, low power solution to infrared surveillance for UGS applications is presented. A 15 X 31 micro infrared camera (MIRC) has been demonstrated which exhibits an f/1 noise equivalent temperature difference sensitivity approximately 67 mK. This sensitivity has been achieved without the use of a thermoelectric cooler for array temperature stabilization thereby significantly reducing the power requirements. The chopperless camera is capable of operating from snapshot mode (1 Hz) to video frame rate (30 Hz). Power consumption of 0.4 W without display, and 0.75 W with display, respectively, has been demonstrated at 30 Hz operation. The 15 X 31 camera demonstrated exhibits a 35 mm camera form factor employing a low cost f/1 singlet optic and LED display, as well as low cost vacuum packaging. A larger 120 X 160 version of the MIRC is also in development and will be discussed. The 120 X 160 MIRC exhibits a substantially smaller form factor and incorporates all the low cost, low power features demonstrated in the 15 X 31 MIRC prototype. In this paper, a-Si microbolometer technology for the MIRC will be presented. Also, the key features and performance parameters of the MIRC are presented.

The conjunction of factors that lead to formation of giant gold provinces and deposits in non-arc settings

USGS Publications Warehouse

Groves, David I.; Goldfarb, Richard J.; Santosh, M.

2016-01-01

In contrast to their province scale similarities, the different giant gold deposit styles show contrasting critical controls at the district to deposit scale. For orogenic gold deposits, the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits, with resultant geometrical and lithostratigraphic complexity as a guide to their location. There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits, and those few giants are essentially preservational exceptions. Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks, enriched in syngenetic gold, to be located below an impermeable cap along antiformal “trends”. Hydrocarbons probably played an important role in concentrating metal. The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock. All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources, partly due to economic factors for this relatively poorly understood, low Cu-Au grade deposit type. The supergiant Olympic Dam deposit, the most shallowly formed deposit among the larger IOCGs, probably owes its origin to eruption of volatile-rich hybrid magma at surface, with formation of a large maar and intense and widespread brecciation, alteration and Cu-Au-U deposition in a huge rock volume.

Liquid film on a circular plate formed by a droplet train impingement

NASA Astrophysics Data System (ADS)

Sanada, Toshiyuki; Yamamoto, Shoya

2017-11-01

Droplet impingement phenomena are found in the wide variety of industrial processes, however the detail of liquid film structure formed by the continuous impact of droplets is not clarified. In this study, we experimentally investigated behavior of liquid film which was formed by a droplet train impact. Especially, we focus on the diameter of hydraulic jump formed on a circular plate. The effects of nozzle diameter, liquid surface tension and liquid flow rate on the jump diameter were investigated. In addition, we compared the liquid film by the droplet train impact with that by a liquid column impact. As a result, the hydraulic jump was observed under the smaller water flow rate condition compare to the liquid column impact. And the jump diameters for the case of droplet train impact were greater than that of liquid column impact. However, the jump diameters for the small surface tension liquid for the case of droplet train impact were smaller than that of liquid column impact. We consider that this phenomenon is related to both high speed lateral flow after droplet impact and splash formation. In addition, the liquid film heights after hydraulic jump on a small circular plate were sensitive to either the droplet train impact or liquid column impact.

Brain tissue volumes in the general elderly population. The Rotterdam Scan Study.

PubMed

Ikram, M Arfan; Vrooman, Henri A; Vernooij, Meike W; van der Lijn, Fedde; Hofman, Albert; van der Lugt, Aad; Niessen, Wiro J; Breteler, Monique M B

2008-06-01

We investigated how volumes of cerebrospinal fluid (CSF), grey matter (GM) and white matter (WM) varied with age, sex, small vessel disease and cardiovascular risk factors in the Rotterdam Scan Study. Participants (n=490; 60-90 years) were non-demented and 51.0% had hypertension, 4.9% had diabetes mellitus, 17.8% were current smoker and 54.0% were former smoker. We segmented brain MR-images into GM, normal WM, white matter lesion (WML) and CSF. Brain infarcts were rated visually. Volumes were expressed as percentage of intra-cranial volume. With increasing age, volumes of total brain, normal WM and total WM decreased; that of GM remained unchanged; and that of WML increased, in both men and women. Excluding persons with infarcts did not alter these results. Persons with larger load of small vessel disease had smaller brain volume, especially normal WM volume. Diastolic blood pressure, diabetes mellitus and current smoking were also related to smaller brain volume. In the elderly, higher age, small vessel disease and cardiovascular risk factors are associated with smaller brain volume, especially WM volume.

Perceived impact of smaller compared with larger-sized bottles of sugar-sweetened beverages on consumption: A qualitative analysis.

PubMed

Mantzari, Eleni; Hollands, Gareth J; Pechey, Rachel; Jebb, Susan; Marteau, Theresa M

2018-01-01

Sugar-sweetened beverage (SSB) consumption increases obesity risk and is linked to adverse health consequences. Large packages increase food consumption, but most evidence comes from studies comparing larger with standard packages, resulting in uncertainty regarding the impact of smaller packages. There is also little research on beverages. This qualitative study explores the experiences of consuming cola from smaller compared with larger bottles, to inform intervention strategies. Sixteen households in Cambridge, England, participating in a feasibility study assessing the impact of bottle size on in-home SSB consumption, received a set amount of cola each week for four weeks in one of four bottle sizes: 1500 ml, 1000 ml, 500 ml, or 250 ml, in random order. At the study end, household representatives were interviewed about their experiences of using each bottle, including perceptions of i) consumption level; ii) consumption-related behaviours; and iii) factors affecting consumption. Interviews were semi-structured and data analysed using the Framework approach. The present analysis focuses specifically on experiences relating to use of the smaller bottles. The smallest bottles were described as increasing drinking occasion frequency and encouraging consumption of numerous bottles in succession. Factors described as facilitating their consumption were: i) convenience and portability; ii) greater numbers of bottles available, which hindered consumption monitoring and control; iii) perceived insufficient quantity per bottle; and iv) positive attitudes. In a minority of cases the smallest bottles were perceived to have reduced consumption, but this was related to practical issues with the bottles that resulted in dislike. The perception of greater consumption and qualitative reports of drinking habits associated with the smallest bottles raise the possibility that the 'portion size effect' has a lower threshold, beyond which smaller portions and packages may increase consumption. This reinforces the need for empirical evidence to assess the in-home impact of smaller bottles on SSB consumption. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Dark tip-tilt sensing

NASA Astrophysics Data System (ADS)

Arcidiacono, Carmelo; Ragazzoni, Roberto; Viotto, Valentina; Bergomi, Maria; Farinato, Jacopo; Magrin, Demetrio; Dima, Marco; Gullieuszik, Marco; Marafatto, Luca

2016-07-01

Dark wavefront sensing in its simplest and more crude form is a quad-cell with a round spot of dark ink acting as occulting disk at the center. This sensor exhibits fainter limiting magnitude than a conventional quad-cell, providing that the size of the occulting disk is slightly smaller than the size of the spot and smaller than the residual jitter movement in closed loop. We present simulations focusing a generic Adaptive Optics system using Natural Guide Stars to provide the tip-tilt signal. We consider a jitter spectrum of the residual correction including amplitudes exceeding the dark disk size.

Reduction of noise radiated from open pipe terminations

NASA Astrophysics Data System (ADS)

Davis, M. R.

1989-07-01

A modified Quincke tube has been tested to determine the extent to which sound radiation from an open tube end can be reduced by conversion of the monopole source into a dipole form. It has been found that directivity patterns of the dipole with approximately 20 dB variation can be achieved provided that the out-of-phase tube ends are not too closely spaced. Very large spacings also reduce the effectiveness of the arrangement in reducing radiated power since the source system does not then approximate a simple dipole. Consideration has been given to compact designs which achieve path length differentials by the use of four concentric tubes. The relative size of the two acoustic paths has to be adjusted to allow for the size effect on radiation, requiring a somewhat larger area for the smaller tube. Through flow would require an opposite adjustment of the smaller tube area in this case if the smaller tube presented a smaller resistance to flow, as is likely since it involves straight-through flow. Flow through the system would increase the tuned operating frequency.

Ultrasonic synthesis of hydroxyapatite in non-cavitation and cavitation modes.

PubMed

Nikolaev, A L; Gopin, A V; Severin, A V; Rudin, V N; Mironov, M A; Dezhkunov, N V

2018-06-01

The size control of materials is of great importance in research and technology because materials of different size and shape have different properties and applications. This paper focuses on the synthesis of hydroxyapatite in ultrasound fields of different frequencies and intensities with the aim to find the conditions which allow control of the particles size. The results are evaluated by X-ray diffraction, Transmission Electron Microscopy, morphological and sedimentation analyses. It is shown that the hydroxyapatite particles synthesized at low intensity non-cavitation regime of ultrasound have smaller size than those prepared at high intensity cavitation regime. The explanation of observed results is based on the idea of formation of vortices at the interface between phosphoric acid and calcium hydroxide solution where the nucleation of hydroxyapatite particles is taken place. Smaller vortices formed at high frequency non-cavitation ultrasound regime provide smaller nucleation sites and smaller resulting particles, compared to vortices and particles obtained without ultrasound. Discovered method has a potential of industrial application of ultrasound for the controlled synthesis of nanoparticles. Copyright © 2018 Elsevier B.V. All rights reserved.

Wear forms of heterogeneous electro-rheological fluids working in a hydraulic clutch system

NASA Astrophysics Data System (ADS)

Ziabska, E.; Duchowski, J.; Olszak, A.; Osowski, K.; Kesy, A.; Kesy, Z.; Choi, S. B.

2017-09-01

The paper presents experimental results concerning the wear of heterogeneous electro-rheological (ER) fluids operating as working fluids in a complex clutch system consisting of a hydrodynamic clutch and a cylinder viscous clutch. The change of electric field intensity in the clutches results in change of sheer stress values in working fluids what causes the change of transmitted torque. This work shows that the most important factors affecting the wear of the ER fluid are the electric field of high intensity, the accompanying electrical breakdown, and the high temperature of the silicone oil. In addition, the water from the humid air absorbed mainly by hygroscopic particles influences a significant impact on the wear of the working fluid. Various forms of wear particles of the fluid depending on the prevailing conditions such as working mode are observed from the microscopic aspects. It is observed that the particles are flattened, rolled out or smashed into smaller fragments, partially melted, wrinkled and glued or caked. In addition, it is identified that the partial destruction of silicone oil is occurred due to the damage of the hydrocarbon chains, as evidenced by the decrease in its viscosity and the presence of the particle matter newly containing silicon.

Morphogenic Protein RodZ Interacts with Sporulation Specific SpoIIE in Bacillus subtilis.

PubMed

Muchová, Katarína; Chromiková, Zuzana; Bradshaw, Niels; Wilkinson, Anthony J; Barák, Imrich

2016-01-01

The first landmark in sporulation of Bacillus subtilis is the formation of an asymmetric septum followed by selective activation of the transcription factor σF in the resulting smaller cell. How the morphological transformations that occur during sporulation are coupled to cell-specific activation of transcription is largely unknown. The membrane protein SpoIIE is a constituent of the asymmetric sporulation septum and is a crucial determinant of σF activation. Here we report that the morphogenic protein, RodZ, which is essential for cell shape determination, is additionally required for asymmetric septum formation and sporulation. In cells depleted of RodZ, formation of asymmetric septa is disturbed and σF activation is perturbed. During sporulation, we found that SpoIIE recruits RodZ to the asymmetric septum. Moreover, we detected a direct interaction between SpoIIE and RodZ in vitro and in vivo, indicating that SpoIIE-RodZ may form a complex to coordinate asymmetric septum formation and σF activation. We propose that RodZ could provide a link between the cell shape machinery and the coordinated morphological and developmental transitions required to form a resistant spore.

Mathematical Models of Cobalt and Iron Ions Catalyzed Microwave Bacterial Deactivation

PubMed Central

Benjamin, Earl; Reznik, Aron; Benjamin, Ellis; Williams, Arthur L.

2007-01-01

Time differences for Enterococcus faecalis, Staphylococcus aureus, and Escherichia coli survival during microwave irradiation (power 130 W) in the presence of aqueous cobalt and iron ions were investigated. Measured dependencies had “bell” shape forms with maximum bacterial viability between 1 – 2 min becoming insignificant at 3 minutes. The deactivation time for E. faecalis, S. aureus and E.coli in the presence of metal ions were smaller compared to a water control (4–5 min). Although various sensitivities to the metal ions were observed, S. aureus and E. coli and were the most sensitive for cobalt and iron, respectively. The rapid reduction of viable bacteria during microwave treatment in the presence of metal ions could be explained by increased metal ion penetration into bacteria. Additionally, microwave irradiation may have increased the kinetic energy of the metal ions resulting in lower survival rates. The proposed mathematical model for microwave heating took into account the “growth” and “death” factors of the bacteria, forming second degree polynomial functions. Good relationships were found between the proposed mathematical models and the experimental data for bacterial deactivation (coefficient of correlation 0.91 – 0.99). PMID:17911658

Art on the Nanoscale and Beyond.

PubMed

Yetisen, Ali K; Coskun, Ahmet F; England, Grant; Cho, Sangyeon; Butt, Haider; Hurwitz, Jonty; Kolle, Mathias; Khademhosseini, Ali; Hart, A John; Folch, Albert; Yun, Seok Hyun

2016-03-02

Methods of forming and patterning materials at the nano- and microscales are finding increased use as a medium of artistic expression, and as a vehicle for communicating scientific advances to a broader audience. While sharing many attributes of other art forms, miniaturized art enables the direct engagement of sensory aspects such as sight and touch for materials and structures that are otherwise invisible to the eye. The historical uses of nano-/microscale materials and imaging techniques in arts and sciences are presented. The motivations to create artwork at small scales are discussed, and representations in scientific literature and exhibitions are explored. Examples are presented using semiconductors, microfluidics, and nanomaterials as the artistic media; these utilized techniques including micromachining, focused ion beam milling, two-photon polymerization, and bottom-up nanostructure growth. Finally, the technological factors that limit the implementation of artwork at miniature scales are identified, and potential future directions are discussed. As research marches toward even smaller length scales, innovative and engaging visualizations and artistic endeavors will have growing implications on education, communication, policy making, media activism, and public perception of science and technology. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Protomagnetar and black hole formation in high-mass stars

NASA Astrophysics Data System (ADS)

Obergaulinger, M.; Aloy, M. Á.

2017-07-01

Using axisymmetric simulations coupling special relativistic magnetohydrodynamics (MHD), an approximate post-Newtonian gravitational potential and two-moment neutrino transport, we show different paths for the formation of either protomagnetars or stellar mass black holes. The fraction of prototypical stellar cores which should result in collapsars depends on a combination of several factors, among which the structure of the progenitor star and the profile of specific angular momentum are probably the foremost. Along with the implosion of the stellar core, we also obtain supernova-like explosions driven by neutrino heating and hydrodynamic instabilities or by magneto-rotational effects in cores of high-mass stars. In the latter case, highly collimated, mildly relativistic outflows are generated. We find that after a rather long post-collapse phase (lasting ≳1 s) black holes may form in cases both of successful and failed supernova-like explosions. A basic trend is that cores with a specific angular momentum smaller than that obtained by standard, one-dimensional stellar evolution calculations form black holes (and eventually collapsars). Complementary, protomagnetars result from stellar cores with the standard distribution of specific angular momentum obtained from prototypical stellar evolution calculations including magnetic torques and moderate to large mass-loss rates.

Cost Is Not Everything.

ERIC Educational Resources Information Center

Clement, Russell T.

1985-01-01

Reports results of survey of 21 smaller to medium-sized (50,000-200,000 volumes) libraries which was conducted to determine factors used to make selection decisions in purchase of automated turnkey systems from established vendors. Factors examined include costs, software, hardware, and vendors for parts A (actual experience) and B (hypothetical…

The predictive efficiency of school bullying versus later offending: a systematic/meta-analytic review of longitudinal studies.

PubMed

Ttofi, Maria M; Farrington, David P; Lösel, Friedrich; Loeber, Rolf

2011-04-01

Although bullying and delinquency share similar risk factors, no previous systematic review has ever been conducted to examine possible links between school bullying and criminal offending later in life. To investigate the extent to which bullying perpetration at school predicts offending later in life, and whether this relation holds after controlling for other major childhood risk factors. Results are based on a thorough systematic review and meta-analysis of studies measuring school bullying and later offending. Effect sizes are based on both published and unpublished studies; longitudinal investigators of 28 studies have conducted specific analyses for our review. The probability of offending up to 11 years later was much higher for school bullies than for non-involved students [odds ratio (OR) = 2.50; 95% confidence interval (CI): 2.03-3.08]. Bullying perpetration was a significant risk factor for later offending, even after controlling for major childhood risk factors (OR = 1.82, 95% CI: 1.55-2.14). Effect sizes were smaller when the follow-up period was longer and larger when bullying was assessed in older children. The age of participants when outcome measures were taken was negatively related with effect sizes. Finally, the summary effect size did not decrease much as the number of controlled risk factors increased. School bullying is a strong and specific risk factor for later offending. Effective anti-bullying programmes should be promoted, and could be viewed as a form of early crime prevention. Such programmes would have a high benefit : cost ratio. Copyright © 2011 John Wiley & Sons, Ltd.

Fabrication and characterization of poly(DL-lactic-co-glycolic acid)/zirconia-hybridized amorphous calcium phosphate composites

PubMed Central

WHITED, BRYCE M.; GOLDSTEIN, AARON S.; SKRTIC, DRAGO; LOVE, BRIAN J.

2010-01-01

Several minerals, such as hydroxyapatite and β-tricalcium phosphate, have been incorporated into bioresorbable polyester bone scaffolds to increase the osteoconductivity both in vitro and in vivo. More soluble forms of calcium phosphate that release calcium and phosphate ions have been postulated as factors that increase osteoblast differentiation and mineralization. Recently, a zirconia-hybridized pyrophosphate-stabilized amorphous calcium phosphate (Zr-ACP) has been synthesized allowing controlled release of calcium and phosphate ions. When incorporated into bioresorbable scaffolds, Zr-ACP has the potential to induce osteoconductivity. In this study, 80–90% (w/v) porous poly(DL-LActic-co-glycolic acid) (PLGA) scaffolds were formed by thermal phase separation from dioxane while incorporating Zr-ACP. Scanning electron microscopy revealed a highly porous structure with a pore size ranging from a few μm to about 100 μm, smaller than we had hoped for. Zr-ACP particles were evenly dispersed in the composite structure and incorporated into the pore walls. The amorphous structure of the Zr-ACP was maintained during composite fabrication, as found by X-ray diffraction. Composite scaffolds had larger compressive yield strengths and moduli compared to pure polymer scaffolds. These initial efforts demonstrate that PLGA/Zr-ACP composites can be formed in ways that ultimately serve as promising bone scaffolds in tissue engineering. PMID:16768292

Terrestrial analogs to lunar sinuous rilles - Kauhako Crater and channel, Kalaupapa, Molokai, and other Hawaiian lava conduit systems

NASA Technical Reports Server (NTRS)

Coombs, C. R.; Hawke, B. R.; Wilson, L.

1990-01-01

Two source vents, one explosive and one effusive erupted to form a cinder cone and low lava shield that together compose the Kalaupapa peninsula of Molokai, Hawaii, A 50-100-m-wide channel/tube system extends 2.3 km northward from kauhako crater in the center of the shield. Based on modeling, a volume of up to about 0.2 cu km of lava erupted at a rate of 260 cu m/sec to flow through the Kauhako conduit system in one of the last eruptive episodes on the peninsula. Channel downcutting by thermal erosion occurred at a rate of about 10 micron/sec to help form the 30-m-deep conduit. Two smaller, secondary tube systems formed east of the main lava channel/tube. Several other lava conduit systems on the islands of Oahu and Hawaii were also compared to the Kauhako and lunar sinuous rille systems. These other lava conduits include Whittington, Kupaianaha, and Mauna Ulu lava tubes. Morphologically, the Hawaiian tube systems studied are very similar to lunar sinuous rilles in that they have deep head craters, sinuous channels, and gentle slopes. Thermal erosion is postulated to be an important factor in the formation of these terrestrial channel systems and by analogy is inferred to be an important process involved in the formation of lunar sinuous rilles.

Terrestrial analogs to lunar sinuous rilles - Kauhako Crater and channel, Kalaupapa, Molokai, and other Hawaiian lava conduit systems

NASA Astrophysics Data System (ADS)

Coombs, C. R.; Hawke, B. R.; Wilson, L.

Two source vents, one explosive and one effusive erupted to form a cinder cone and low lava shield that together compose the Kalaupapa peninsula of Molokai, Hawaii, A 50-100-m-wide channel/tube system extends 2.3 km northward from kauhako crater in the center of the shield. Based on modeling, a volume of up to about 0.2 cu km of lava erupted at a rate of 260 cu m/sec to flow through the Kauhako conduit system in one of the last eruptive episodes on the peninsula. Channel downcutting by thermal erosion occurred at a rate of about 10 micron/sec to help form the 30-m-deep conduit. Two smaller, secondary tube systems formed east of the main lava channel/tube. Several other lava conduit systems on the islands of Oahu and Hawaii were also compared to the Kauhako and lunar sinuous rille systems. These other lava conduits include Whittington, Kupaianaha, and Mauna Ulu lava tubes. Morphologically, the Hawaiian tube systems studied are very similar to lunar sinuous rilles in that they have deep head craters, sinuous channels, and gentle slopes. Thermal erosion is postulated to be an important factor in the formation of these terrestrial channel systems and by analogy is inferred to be an important process involved in the formation of lunar sinuous rilles.

Contribution of intravascular versus interstitial purines and nitric oxide in the regulation of exercise hyperaemia in humans

PubMed Central

Hellsten, Y; Nyberg, M; Mortensen, S P

2012-01-01

The regulation of blood flow to skeletal muscle involves a complex interaction between several locally formed vasodilators that are produced both in the skeletal muscle interstitium and intravascularly. The gas nitric oxide (NO) and the purines ATP and adenosine, are potent vasodilators that are formed by multiple cell types and released into the skeletal muscle interstitium and in plasma in response to muscle contraction. Cellular sources of ATP and NO in plasma are erythrocytes and endothelial cells, whereas interstitial sources are skeletal muscle cells and endothelial cells. Adenosine originates primarily from extracellular degradation of ATP. During exercise the concentrations of ATP and adenosine increase markedly in the interstitium with smaller increases occurring in plasma, and thus the interstitial concentration during exercise is severalfold higher than in plasma. The concentration of NO metabolites (NOx) in interstitium and plasma does not change during exercise and is similar in the two compartments. Adenosine and NO have been shown to contribute to exercise hyperaemia whereas the role of ATP remains unclear due to lack of specific purinergic receptor blockers. The relative role of intravascular versus interstitial vasodilators is not known but evidence suggests that both compartments are important. In cardiovascular disease, a reduced capacity to form adenosine in the muscle interstitium may be a contributing factor in increased peripheral vascular resistance. PMID:22733661

Analysis of hepatitis B vaccination behavior and vaccination willingness among migrant workers from rural China based on protection motivation theory

PubMed Central

Liu, Rugang; Li, Youwei; Wangen, Knut R.; Maitland, Elizabeth; Nicholas, Stephen; Wang, Jian

2016-01-01

ABSTRACT Introduction: With China's accelerating urbanization, migrant workers comprise up to 40% of the urban population of China's largest cities. More mobile than non-migrant urban dwellers, migrants are more likely to contract and spread hepatitis B (HB) than non-migrants. Due to the mandatory system of household registration (hukou), migrants are less likely to be covered by national HB immunization programs and also to have more limited access to public health services where they work than non-migrants. Migrants form a significant sub-group in all Chinese cities posing unique public policy vaccination challenges. Objective: Using protection motivation theory (PMT), we developed and measured HB cognitive variables and analyze the factors affecting HB vaccination behavior and willingness to vaccinate by migrant workers. We propose public policy interventions to increase HB vaccination rates of migrant workers. Methods: We developed a questionnaire to collect information on the HB vaccination characteristics of 1684 respondents from 6 provinces and Beijing. Exploratory factor analysis was used to create PMT variables and a binary logistic regression model was used to analyze the factors affecting migrant workers' HB vaccination behavior and willingness to vaccinate. Results: Vulnerability and response-efficacy were significant PMT cognition factors determining HB vaccination behavior. The HB vaccination rate for migrants decreased with increasing age and was smaller for the primary education than the high education group. The vaccination rate of the medical insurance group was significantly greater than the non-insured group, and the vaccination probability was significantly higher for the self-rated good health compared to the self-rated poor health group. Geographical birth location mattered: the vaccination rate for Beijing city and Ningxia province migrants were higher than for Hebei province and the vaccination rate was lower for migrants born far from health facilities compared to those located middle-near distances from health facilities. We also studied vaccination willingness for the unvaccinated group. For this group, vulnerability and self-efficacy cognition factors were significant factors determining HB vaccination willingness. The probability of willingness to vaccinate for the 46+ age group was significantly smaller than the 16–25 age group and the willingness to vaccinate was lower in Jiangsu and Hainan province than in Hebei province. Conclusion: Increased knowledge of HB cognition is an effective way for improving HB vaccination behavior and HB vaccination willingness of migrant workers. We also found that health intervention policies should focus on older migrants (age 46+), without medical insurance, with poorer self-reported health status and poor health services accessibility. PMID:27078191

Analysis of hepatitis B vaccination behavior and vaccination willingness among migrant workers from rural China based on protection motivation theory.

PubMed

Liu, Rugang; Li, Youwei; Wangen, Knut R; Maitland, Elizabeth; Nicholas, Stephen; Wang, Jian

2016-05-03

With China's accelerating urbanization, migrant workers comprise up to 40% of the urban population of China's largest cities. More mobile than non-migrant urban dwellers, migrants are more likely to contract and spread hepatitis B (HB) than non-migrants. Due to the mandatory system of household registration (hukou), migrants are less likely to be covered by national HB immunization programs and also to have more limited access to public health services where they work than non-migrants. Migrants form a significant sub-group in all Chinese cities posing unique public policy vaccination challenges. Using protection motivation theory (PMT), we developed and measured HB cognitive variables and analyze the factors affecting HB vaccination behavior and willingness to vaccinate by migrant workers. We propose public policy interventions to increase HB vaccination rates of migrant workers. We developed a questionnaire to collect information on the HB vaccination characteristics of 1684 respondents from 6 provinces and Beijing. Exploratory factor analysis was used to create PMT variables and a binary logistic regression model was used to analyze the factors affecting migrant workers' HB vaccination behavior and willingness to vaccinate. Vulnerability and response-efficacy were significant PMT cognition factors determining HB vaccination behavior. The HB vaccination rate for migrants decreased with increasing age and was smaller for the primary education than the high education group. The vaccination rate of the medical insurance group was significantly greater than the non-insured group, and the vaccination probability was significantly higher for the self-rated good health compared to the self-rated poor health group. Geographical birth location mattered: the vaccination rate for Beijing city and Ningxia province migrants were higher than for Hebei province and the vaccination rate was lower for migrants born far from health facilities compared to those located middle-near distances from health facilities. We also studied vaccination willingness for the unvaccinated group. For this group, vulnerability and self-efficacy cognition factors were significant factors determining HB vaccination willingness. The probability of willingness to vaccinate for the 46+ age group was significantly smaller than the 16-25 age group and the willingness to vaccinate was lower in Jiangsu and Hainan province than in Hebei province. Increased knowledge of HB cognition is an effective way for improving HB vaccination behavior and HB vaccination willingness of migrant workers. We also found that health intervention policies should focus on older migrants (age 46+), without medical insurance, with poorer self-reported health status and poor health services accessibility.

Controlled transition dipole alignment of energy donor and energy acceptor molecules in doped organic crystals, and the effect on intermolecular Förster energy transfer.

PubMed

Wang, Huan; Yue, Bailing; Xie, Zengqi; Gao, Bingrong; Xu, Yuanxiang; Liu, Linlin; Sun, Hongbo; Ma, Yuguang

2013-03-14

The orientation factor κ(2) ranging from 0 to 4, which depends on the relative orientation of the transition dipoles of the energy donor (D) and the energy acceptor (A) in space, is one of the pivotal factors deciding the efficiency and directionality of resonance energy transfer (RET) in a D-A molecular system. In this work, tetracene (Tc) and pentacene (Pc) are successfully doped in a trans-1,4-distyrylbenzene (DSB) crystalline lattice to form definite D-A mutually perpendicular transition dipole orientations. The cross D-A dipole arrangement results in an extremely small orientation factor, which is about two orders smaller than that in the disordered films. The energy transfer properties from the host (DSB) to the guest (Tc/Pc) were investigated in detail by steady-state as well as time-resolved fluorescence spectroscopy. Our experimental research results show that the small value of κ(2) allows less or partial energy transfer from the host (DSB) to the guest (Tc) in a wide range of guest concentration, with the Förster distance of around 1.5 nm. By controlling the doping concentrations in the Tc and Pc doubly doped DSB crystals, we demonstrate, as an example, for the first time the application of the restricted energy transfer by D-A cross transition dipole arrangement for preparation of a large-size, white-emissive organic crystal with the CIE coordinates of (0.36, 0.37) approaching an ideal white light. In contrast, Tc is also doped in an anthracene crystalline lattice to form head-to-tail D-A transition dipole alignment, which is proved to be highly effective to promote the intermolecular energy transfer. In this doped system, the orientation factor is relatively large and the Förster distance is around 7 nm.

The plane strain shear fracture of the advanced high strength steels

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

Sun, Li, E-mail: li.sun@gm.com

2013-12-16

The “shear fracture” which occurs at the high-curvature die radii in the sheet metal forming has been reported to remarkably limit the application of the advanced high strength steels (AHSS) in the automobile industry. However, this unusual fracture behavior generally cannot be predicted by the traditional forming limit diagram (FLD). In this research, a new experimental system was developed in order to simulate the shear fracture, especially at the plane strain state which is the most common state in the auto-industry and difficult to achieve in the lab due to sample size. Furthermore, the system has the capability to operatemore » in a strain rate range from quasi-static state to the industrial forming state. One kinds of AHSS, Quenching-Partitioning (QP) steels have been performed in this test and the results show that the limiting fracture strain is related to the bending ratio and strain rate. The experimental data support that deformation-induced heating is an important cause of “shear fracture” phenomena for AHSS: a deformation-induced quasi-heating caused by smaller bending ratio and high strain rate produce a smaller limiting plane strain and lead a “shear fracture” in the component.« less

Increased enzyme production under liquid culture conditions in the industrial fungus Aspergillus oryzae by disruption of the genes encoding cell wall α-1,3-glucan synthase.

PubMed

Miyazawa, Ken; Yoshimi, Akira; Zhang, Silai; Sano, Motoaki; Nakayama, Mayumi; Gomi, Katsuya; Abe, Keietsu

2016-09-01

Under liquid culture conditions, the hyphae of filamentous fungi aggregate to form pellets, which reduces cell density and fermentation productivity. Previously, we found that loss of α-1,3-glucan in the cell wall of the fungus Aspergillus nidulans increased hyphal dispersion. Therefore, here we constructed a mutant of the industrial fungus A. oryzae in which the three genes encoding α-1,3-glucan synthase were disrupted (tripleΔ). Although the hyphae of the tripleΔ mutant were not fully dispersed, the mutant strain did form smaller pellets than the wild-type strain. We next examined enzyme productivity under liquid culture conditions by transforming the cutinase-encoding gene cutL1 into A. oryzae wild-type and the tripleΔ mutant (i.e. wild-type-cutL1, tripleΔ-cutL1). A. oryzae tripleΔ-cutL1 formed smaller hyphal pellets and showed both greater biomass and increased CutL1 productivity compared with wild-type-cutL1, which might be attributable to a decrease in the number of tripleΔ-cutL1 cells under anaerobic conditions.

Balloon borne Antarctic frost point measurements and their impact on polar stratospheric cloud theories

NASA Technical Reports Server (NTRS)

Rosen, James M.; Hofmann, D. J.; Carpenter, J. R.; Harder, J. W.; Oltmans, S. J.

1988-01-01

The first balloon-borne frost point measurements over Antarctica were made during September and October, 1987 as part of the NOZE 2 effort at McMurdo. The results indicate water vapor mixing ratios on the order of 2 ppmv in the 15 to 20 km region which is somewhat smaller than the typical values currently being used significantly smaller than the typical values currently being used in polar stratospheric cloud (PSC) theories. The observed water vapor mixing ratio would correspond to saturated conditions for what is thought to be the lowest stratospheric temperatures encountered over the Antarctic. Through the use of available lidar observations there appears to be significant evidence that some PSCs form at temperatures higher than the local frost point (with respect to water) in the 10 to 20 km region thus supporting the nitric acid theory of PSC composition. Clouds near 15 km and below appear to form in regions saturated with respect to water and thus are probably mostly ice water clouds although they could contain relatively small amounts of other constituents. Photographic evidence suggests that the clouds forming above the frost point probably have an appearance quite different from the lower altitude iridescent, colored nacreous clouds.

HEASD PM EXPOSURE FACTORS- IMPROVE UNDERSTANDING OF THE FACTORS WHICH DETERMINE HUMANS' EXPOSURE TO PARTICLES SMALLER THAN 2.5 MICRONS

EPA Science Inventory

In July 1997, the EPA Administrator issued a new Particulate Matter (PM-2.5) National Ambient Air Quality Standards (NAAQS) that had been developed largely on the basis of epidemiological studies. These studies found a consistent association between ambient PM concentrations and...

Prevalence and risk factors for scrub typhus in South India.

PubMed

Trowbridge, Paul; P, Divya; Premkumar, Prasanna S; Varghese, George M

2017-05-01

To determine the prevalence and risk factors of scrub typhus in Tamil Nadu, South India. We performed a clustered seroprevalence study of the areas around Vellore. All participants completed a risk factor survey, with seropositive and seronegative participants acting as cases and controls, respectively, in a risk factor analysis. After univariate analysis, variables found to be significant underwent multivariate analysis. Of 721 people participating in this study, 31.8% tested seropositive. By univariate analysis, after accounting for clustering, having a house that was clustered with other houses, having a fewer rooms in a house, having fewer people living in a household, defecating outside, female sex, age >60 years, shorter height, lower weight, smaller body mass index and smaller mid-upper arm circumference were found to be significantly associated with seropositivity. After multivariate regression modelling, living in a house clustered with other houses, female sex and age >60 years were significantly associated with scrub typhus exposure. Overall, scrub typhus is much more common than previously thought. Previously described individual environmental and habitual risk factors seem to have less importance in South India, perhaps because of the overall scrub typhus-conducive nature of the environment in this region. © 2017 John Wiley & Sons Ltd.

Pressure-dependent boron isotopic fractionation observed by column chromatography

NASA Astrophysics Data System (ADS)

Musashi, M.; Oi, T.; Matsuo, M.; Nomura, M.

2007-12-01

Boron isotopic fractionation factor ( S ) between boron taken up in strongly basic anion exchange resin and boron in aqueous solution was determined by breakthrough column chromatography at 5 and 17 MPa at 25°C, using 0.1 mmol/L boric acid solution as feed solution. The S values obtained were 1.018 and 1.012, respectively, which were smaller than the value reported by using the same chromatographic method at atmospheric pressure at 25°C with the boron concentration of 10 mmol/L, but were larger than the values at the same condition with much higher concentration of 100 and 501 mmol/L, indicating that borate-polymerization reducing the isotopic fractionation was negligible. However, calculations based on the theory of isotope distribution between two phases estimated that 21% (5MPa) and 47% (17MPa) of boron taken up in the resin phase was in the three-coordinated B(OH)3-form, instead of in the four-coordinated B(OH)4--form, at high pressures even with the very diluted solution. We discussed this discrepancy by introducing (1) hydration or (2) a partial molar volume difference between isotopic molecules. It was inferred that borate ions were partially dehydrated upon transfer from the solution phase to the resin phase at high pressures, which resulted in smaller S values compared with those at the atmospheric pressure. Alternatively, it was likely that the S value decreased with increasing pressure, because the difference of the partial isotopic molar volumes between 10B(OH)3 and 11B(OH)3 was larger than that between 10B(OH)4- and 11B(OH)4-. If either will be the case, the influence of a pressure upon the isotope effect may not be negligible for boron isotopic exchange equilibrium. This knowledge is crucial for the principle of the boron isotopic pH-metry reconstructing a chemical variation at the paleo-deep oceanic environment where the early life may have been evolved.

Extracellular Polymeric Substance Production and Aggregated Bacteria Colonization Influence the Competition of Microbes in Biofilms.

PubMed

Jayathilake, Pahala G; Jana, Saikat; Rushton, Steve; Swailes, David; Bridgens, Ben; Curtis, Tom; Chen, Jinju

2017-01-01

The production of extracellular polymeric substance (EPS) is important for the survival of biofilms. However, EPS production is costly for bacteria and the bacterial strains that produce EPS (EPS+) grow in the same environment as non-producers (EPS-) leading to competition between these strains for nutrients and space. The outcome of this competition is likely to be dependent on factors such as initial attachment, EPS production rate, ambient nutrient levels and quorum sensing. We use an Individual-based Model (IbM) to study the competition between EPS+ and EPS- strains by varying the nature of initial colonizers which can either be in the form of single cells or multicellular aggregates. The microbes with EPS+ characteristics obtain a competitive advantage if they initially colonize the surface as smaller aggregates and are widely spread-out between the cells of EPS-, when both are deposited on the substratum. Furthermore, the results show that quorum sensing-regulated EPS production may significantly reduce the fitness of EPS producers when they initially deposit as aggregates. The results provide insights into how the distribution of bacterial aggregates during initial colonization could be a deciding factor in the competition among different strains in biofilms.

Preconditioning 2D Integer Data for Fast Convex Hull Computations.

PubMed

Cadenas, José Oswaldo; Megson, Graham M; Luengo Hendriks, Cris L

2016-01-01

In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q) ≤ n the algorithm executes in time within O(n); second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n) time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q) ≤ n holds; the smaller the ratio min(p, q)/n is in the dataset, the greater the speedup factor achieved.

Galactic Angular Momentum in Cosmological Zoom-in Simulations. I. Disk and Bulge Components and the Galaxy-Halo Connection

NASA Astrophysics Data System (ADS)

Sokołowska, Aleksandra; Capelo, Pedro R.; Fall, S. Michael; Mayer, Lucio; Shen, Sijing; Bonoli, Silvia

2017-02-01

We investigate the angular momentum evolution of four disk galaxies residing in Milky-Way-sized halos formed in cosmological zoom-in simulations with various sub-grid physics and merging histories. We decompose these galaxies, kinematically and photometrically, into their disk and bulge components. The simulated galaxies and their components lie on the observed sequences in the j *-M * diagram, relating the specific angular momentum and mass of the stellar component. We find that galaxies in low-density environments follow the relation {j}* \\propto {M}* α past major mergers, with α ˜ 0.6 in the case of strong feedback, when bulge-to-disk ratios are relatively constant, and α ˜ 1.4 in the other cases, when secular processes operate on shorter timescales. We compute the retention factors (I.e., the ratio of the specific angular momenta of stars and dark matter) for both disks and bulges and show that they vary relatively slowly after averaging over numerous but brief fluctuations. For disks, the retention factors are usually close to unity, while for bulges, they are a few times smaller. Our simulations therefore indicate that galaxies and their halos grow in a quasi-homologous way.

The SK3 channel promotes placental vascularization by enhancing secretion of angiogenic factors.

PubMed

Rada, Cara C; Murray, Grace; England, Sarah K

2014-11-15

Proper placental perfusion is essential for fetal exchange of oxygen, nutrients, and waste with the maternal circulation. Impairment of uteroplacental vascular function can lead to pregnancy complications, including preeclampsia and intrauterine growth restriction (IUGR). Potassium channels have been recognized as regulators of vascular proliferation, angiogenesis, and secretion of vasoactive factors, and their dysfunction may underlie pregnancy-related vascular diseases. Overexpression of one channel in particular, the small-conductance calcium-activated potassium channel 3 (SK3), is known to increase vascularization in mice, and mice overexpressing the SK3 channel (SK3(T/T) mice) have a high rate of fetal demise and IUGR. Here, we show that overexpression of SK3 causes fetal loss through abnormal placental vascularization. We previously reported that, at pregnancy day 14, placentas isolated from SK3(T/T) mice are smaller than those obtained from wild-type mice. In this study, histological analysis reveals that SK3(T/-) placentas at this stage have abnormal placental morphology, and microcomputed tomography shows that these placentas have significantly larger and more blood vessels than those from wild-type mice. To identify the mechanism by which these vascularization defects occur, we measured levels of vascular endothelial growth factor (VEGF), placental growth factor, and the soluble form of VEGF receptor 1 (sFlt-1), which must be tightly regulated to ensure proper placental development. Our data reveal that overexpression of SK3 alters systemic and placental ratios of the angiogenic factor VEGF to antiangiogenic factor sFlt-1 throughout pregnancy. Additionally, we observe increased expression of hypoxia-inducing factor 2α in SK3(T/-) placentas. We conclude that the SK3 channel modulates placental vascular development and fetal health by altering VEGF signaling. Copyright © 2014 the American Physiological Society.

Spins of primordial black holes formed in the matter-dominated phase of the Universe

NASA Astrophysics Data System (ADS)

Harada, Tomohiro; Yoo, Chul-Moon; Kohri, Kazunori; Nakao, Ken-Ichi

2017-10-01

Angular momentum plays very important roles in the formation of primordial black holes in the matter-dominated phase of the Universe if it lasts sufficiently long. In fact, most collapsing masses are bounced back due to centrifugal force, since angular momentum significantly grows before collapse. For masses with q ≤qc≃2.4 I1 /3σH1 /3 , where q is a nondimensional initial quadrupole moment parameter, σH is the density fluctuation at horizon entry t =tH, and I is a parameter of the order of unity, angular momentum gives a suppression factor ˜exp (-0.15 I4 /3σH-2 /3) to the production rate. As for masses with q >qc, the suppression factor is even stronger as ˜exp (-0.0046 q4/σH2) . We derive the spin distribution of primordial black holes and find that most of the primordial black holes are rapidly rotating near the extreme value a*=1 , where a* is the nondimensional Kerr parameter at their formation. The smaller σH is, the stronger the tendency towards the extreme rotation. Combining this result with the effect of anisotropy, we numerically and semianalytically estimate the production rate β0 of primordial black holes. Then we find that β0≃1.9 ×10-6fq(qc)I6σH2exp (-0.15 I4 /3σH-2 /3) for σH≲0.005 , while β0≃0.05556 σH5 for 0.005 ≲σH≲0.2 , where fq(qc) is the fraction of masses whose q is smaller than qc and we assume fq(qc) is not too small. We argue that matter domination significantly enhances the production of primordial black holes despite the suppression factor. If the end time tend of the matter-dominated phase satisfies tend≲(0.4 I σH)-1tH, the effect of the finite duration significantly suppresses primordial black hole formation and weakens the tendency towards large spins.

Connective tissue growth factor and integrin αvβ6: a new pair of regulators critical for ductular reaction and biliary fibrosis in mice.

PubMed

Pi, Liya; Robinson, Paulette M; Jorgensen, Marda; Oh, Seh-Hoon; Brown, Alicia R; Weinreb, Paul H; Trinh, Thu Le; Yianni, Protopapadakis; Liu, Chen; Leask, Andrew; Violette, Shelia M; Scott, Edward W; Schultz, Gregory S; Petersen, Bryon E

2015-02-01

Connective tissue growth factor (CTGF) is a matricellular protein that mediates cell-matrix interaction through various subtypes of integrin receptors. This study investigated the role of CTGF and integrin αvβ6 in hepatic progenitor/oval cell activation, which often occurs in the form of ductular reactions (DRs) when hepatocyte proliferation is inhibited during severe liver injury. CTGF and integrin αvβ6 proteins were highly expressed in DRs of human cirrhotic livers and cholangiocarcinoma. Confocal microscopy analysis of livers from Ctgf promoter-driven green fluorescent protein reporter mice suggested that oval cells and cholangiocytes were the main sources of CTGF and integrin αvβ6 during liver injury induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Deletion of exon 4 of the Ctgf gene using tamoxifen-inducible Cre-loxP system down-regulated integrin αvβ6 in DDC-damaged livers of knockout mice. Ctgf deficiency or inhibition of integrin αvβ6, by administrating the neutralizing antibody, 6.3G9 (10 mg/kg body weight), caused low levels of epithelial cell adhesion molecule and cytokeratin 19 gene messenger RNAs. Also, there were smaller oval cell areas, fewer proliferating ductular epithelial cells, and lower cholestasis serum markers within 2 weeks after DDC treatment. Associated fibrosis was attenuated, as indicated by reduced expression of fibrosis-related genes, smaller areas of alpha-smooth muscle actin staining, and low collagen production based on hydroxyproline content and Sirius Red staining. Finally, integrin αvβ6 could bind to CTGF mediating oval cell adhesion to CTGF and fibronection substrata and promoting transforming growth factor (TGF)-β1 activation in vitro. CTGF and integrin αvβ6 regulate oval cell activation and fibrosis, probably through interacting with their common matrix and signal partners, fibronectin and TGF-β1. CTGF and integrin αvβ6 are potential therapeutic targets to control DRs and fibrosis in related liver disease. © 2014 by the American Association for the Study of Liver Diseases.

Emulsifying and foaming properties of commercial yellow pea (Pisum sativum L.) seed flours.

PubMed

Aluko, Rotimi E; Mofolasayo, Olawunmi A; Watts, Beverley M

2009-10-28

Commercial yellow pea seed flours prepared by a patented wet-milling process and pea protein isolate (PPI) were analyzed for emulsifying and foaming properties at pH 3.0, 5.0, and 7.0 and compared to soybean protein isolate (SPI). PPI and SPI formed emulsions with significantly smaller (p < 0.05) oil droplet sizes, 16-30 and 23-54 microm, respectively, than flours that primarily contained fiber such as Centara III and IV, or those that consisted mainly of starch: Centu-tex, Uptake 80 and Accu-gel. PPI was a better emulsifier than SPI at pH 7.0, and a better foaming agent at pH 3.0 and pH 7.0, although foaming capacity varied with sample concentration. Centu-tex and Uptake 80 have exactly the same chemical composition, but the latter has a much smaller flour particle size range, and had significantly smaller (p < 0.05) emulsion oil droplets. Incorporation of pea starch into SPI emulsions produced a synergistic effect that led to significant increases (p < 0.05) in emulsification capacity (reduced emulsion oil droplet size) when compared to SPI or starch alone. These results showed that PPI had generally significantly higher (p < 0.05) emulsion and foam forming properties than SPI, and that pea starch could be used to improve the quality of SPI-stabilized food emulsions.

Study of thermal stability of (3-aminopropyl)trimethoxy silane-grafted titanate nanotubes for application as nanofillers in polymers.

PubMed

Plodinec, Milivoj; Gajović, Andreja; Iveković, Damir; Tomašić, Nenad; Zimmermann, Boris; Macan, Jelena; Haramina, Tatjana; Su, D S; Willinger, Marc

2014-10-31

Protonated titanate nanotubes (TiNT-H) were surface-modified with (3-aminopropyl)trimethoxy silane (APTMS) by a novel method suitable for the syntheses of large amounts of materials at a low cost. The usage of prepared nanotubes for polymer reinforcement was studied. Since the thermal stability of the nanofiller was important to preserve its functional properties, its stability was studied by in situ high-temperature measurements. The most thermally stable nanotubes were silanized for 20 min and used for the preparation of epoxy-based nanocomposites. The nanofiller formed smaller (a few hundred nm) and larger (a few μm) aggregates in the polymer matrix, and the amount of aggregates increased as the nanofiller content increased. The APTMS-modified titanate nanotubes bonded well with the epoxy matrix since amine groups on the TiNT's surface can react with an epoxy group to form covalent bonds between the matrix and the nanofiller. A very small addition (0.19-1.52 wt%) of the nanotubes significantly increased the glass transition temperature and the modulus in the rubbery state of the epoxy-based polymer. Smaller nanofiller content leads to a larger increase in these parameters and therefore better dynamic mechanical properties due to the smaller amount of large aggregates. APTMS-modified titanate nanotubes have proven to be a promising nanofiller in epoxy-based nanocomposites.

Predictable evolution toward flightlessness in volant island birds.

PubMed

Wright, Natalie A; Steadman, David W; Witt, Christopher C

2016-04-26

Birds are prolific colonists of islands, where they readily evolve distinct forms. Identifying predictable, directional patterns of evolutionary change in island birds, however, has proved challenging. The "island rule" predicts that island species evolve toward intermediate sizes, but its general applicability to birds is questionable. However, convergent evolution has clearly occurred in the island bird lineages that have undergone transitions to secondary flightlessness, a process involving drastic reduction of the flight muscles and enlargement of the hindlimbs. Here, we investigated whether volant island bird populations tend to change shape in a way that converges subtly on the flightless form. We found that island bird species have evolved smaller flight muscles than their continental relatives. Furthermore, in 366 populations of Caribbean and Pacific birds, smaller flight muscles and longer legs evolved in response to increasing insularity and, strikingly, the scarcity of avian and mammalian predators. On smaller islands with fewer predators, birds exhibited shifts in investment from forelimbs to hindlimbs that were qualitatively similar to anatomical rearrangements observed in flightless birds. These findings suggest that island bird populations tend to evolve on a trajectory toward flightlessness, even if most remain volant. This pattern was consistent across nine families and four orders that vary in lifestyle, foraging behavior, flight style, and body size. These predictable shifts in avian morphology may reduce the physical capacity for escape via flight and diminish the potential for small-island taxa to diversify via dispersal.

Geochemical survey of the Devil's Den Roadless Area, Rutland and Windsor counties, Vermont

USGS Publications Warehouse

Slack, J.F.; Atelsek, P.J.; Grosz, A.E.

1985-01-01

The Devils Den area is named for a large undercut cliff (Dale, 1915, p. 21) developed in Precambrian basement rocks. This undercut cliff forms a broad natural cave immediately west of and below Forest Service Road 10, at the head of Mt. Tabor Brook. Another much smaller cave is present in dolomite of probable Paleozoic (Early Cambrian) age on the east side of the same road. This smaller cave apparently is of artificial origin, having been made during early mining of the dolomite (Dale, 1915, p. 21). This man-made cave is the only evidence of previous mining activity within the study area.

Ghostly Halos in Dwarf Galaxies: a probe of star formation in the Early Universe

NASA Astrophysics Data System (ADS)

Kang, Hoyoung; Ricotti, Massimo

2016-01-01

We carry out numerical simulations to characterize the size, stellar mass, and stellar mass surface density of extended stellar halos in dwarf galaxies as a function of dark matter halo mass. We expect that for galaxies smaller than a critical value, these ghostly halos will not exist because the smaller galactic subunits that build it up, do not form any stars. The detection of ghostly halos around isolated dwarf galaxies is a sensitive test of the efficiency of star formation in the first galaxies and of whether ultra-faint dwarf satellites of the Milky Way are fossils of the first galaxies.

Ring-mold craters in lineated valley fill and lobate debris aprons on Mars: Evidence for subsurface glacial ice

NASA Astrophysics Data System (ADS)

Kress, Ailish M.; Head, James W.

2008-12-01

Ring-mold craters (RMCs), concentric crater forms shaped like a truncated torus and named for their similarity to the cooking implement, are abundant in lobate debris aprons (LDA) and lineated valley fill (LVF) in the northern mid-latitudes on Mars, but are not seen in surrounding terrain. LDA and LVF have been interpreted to form by flow of debris, but uncertainty remains concerning the mechanism of flow, with hypotheses ranging from pore-ice-assisted creep of talus to debris-covered glaciers. RMCs average less than a few hundred meters in diameter and occur in association with normal bowl-shaped impact craters whose average diameters are commonly less than RMCs. On the basis of their morphologic similarities to laboratory impact craters formed in ice and the physics of impact cratering into layered material, we interpret the unusual morphology of RMCs to be the result of impact into a relatively pure ice substrate below a thin regolith, with strength-contrast properties, spallation, viscous flow and sublimation being factors in the development of the ring-mold shape. Associated smaller bowl-shaped craters are interpreted to have formed within a layer of regolith-like sublimation till overlying the ice substrate. Estimates of crater depths of excavation between populations of bowl-shaped and ring-mold craters suggest that the debris layer is relatively thin. These results support the hypothesis that LDA and LVF formed as debris-covered glaciers and predict that many hundreds of meters of ice remain today in LDA and LVF deposits, beneath a veneer of sublimation till. RMCs can be used in other parts of Mars to predict and assess the presence of ancient ice-related deposits.

Curcumin-Loading-Dependent Stability of PEGMEMA-Based Micelles Affects Endocytosis and Exocytosis in Colon Carcinoma Cells.

PubMed

Chang, Teddy; Trench, David; Putnam, Joshua; Stenzel, Martina H; Lord, Megan S

2016-03-07

Polymeric micelles were formed from poly(poly(ethylene glycol) methyl ether methacrylate)-block-poly(styrene) (P(PEGMEMA)-b-PS) block copolymer of two different chain lengths. The micelles formed were approximately 16 and 46 nm in diameter and used to encapsulate curcumin. Upon loading of the curcumin into the micelles, their size increased to approximately 34 and 80 nm in diameter, respectively, with a loading efficiency of 58%. The unloaded micelles were not cytotoxic to human colon carcinoma cells, whereas only the smaller loaded micelles were cytotoxic after 72 h of exposure. The micelles were rapidly internalized by the cells within minutes of exposure, with the loaded micelles internalized to a greater extent owing to their enhanced stability compared to that of the unloaded micelles. The larger micelles were more rapidly internalized and exocytosed than the smaller micelles, demonstrating the effect of micelle size and drug loading on drug delivery and cytotoxicity.

The use of solid-state reactions with volume loss to engineer stress and porosity into the fiber-matrix interface of a ceramic composite

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

Hay, R.S.

The effect of the 11 vol% losing during reaction of yttrium-aluminas garnet (YAG) and zirconia was observed in zirconia coated single-crystal alumina fiber-YAG matrix composites. The reaction caused plastic deformation in the alumina fibers, and possibly a minor amount of porosity at fiber-matrix interfaces that was usually indistinguishable from matrix porosity. The results were analyzed by models for diffusive cavitation modified to use reaction self-stress. Crack-healing, tensile stress states along the reaction front that approach plane stress, and the small volume of self-stressed material make crack-like pores unlikely at the high temperatures required for reaction. Smaller matrix grains might promotemore » formation of smaller cavities but are also incompatible with high temperature. Both modeling and experiment suggest that sufficient porosity for crack deflection and fiber pullout cannot form unless processing methods that form dense composites at lower temperatures are used.« less

A Cost Benefit Analysis of Emerging LED Water Purification Systems in Expeditionary Environments

DTIC Science & Technology

2017-03-23

the initial contingency response phase, ROWPUs are powered by large generators which require relatively large amounts of fossil fuels. The amount of...they attract and cling together forming a larger particle (Chem Treat, 2016). Flocculation is the addition of a polymer to water that clumps...smaller particles together to form larger particles. The idea for both methods is that larger particles will either settle out of or be removed from the

Forming Giant Planet Cores by Pebble Accretion -- Why Slow and Steady wins the Race

NASA Astrophysics Data System (ADS)

Kretke, Katherine A.; Levison, Harold F.

2014-05-01

In recent years there has been a radical new solution proposed to solve the problem of giant planet core formation. "Pebbles", particles ranging from centimeters to meters in size, have been shown to accrete extremely efficiently due to aerodynamic drag. Large capture cross-sections combined with fast pebble drift rates can allow a single planetesimal to grow from Ceres size to 10s of Earth masses well within the lifetime of gaseous circumstellar disks. However, at large sizes, the the capture-cross section of pebbles goes with the Hill sphere, forcing pebble accretion to becomes a fundamentally "oligarchic-like" process. This makes it difficult to form a few giant planet cores; instead a more generic result is many 10s to 100s of competing oligarchs. In this work, we present a way to get around this oligarchic dilemma If pebbles are assumed to form slowly over a long period of time, then the planetesimal growth rates are slow enough for the planetesimals to dynamically excite each other. As the larger planetisimals/proto-planets stir their smaller companions, these smaller bodies are excited to such a degree that they spend only a small fraction of their orbits embedded in the cooler pebble disk. This allows the larger bodies to starve their neighbors and maintain a relative runaway growth rate to high mass, effectively forming the cores of giant planets.

Tensor Factorization for Low-Rank Tensor Completion.

PubMed

Zhou, Pan; Lu, Canyi; Lin, Zhouchen; Zhang, Chao

2018-03-01

Recently, a tensor nuclear norm (TNN) based method was proposed to solve the tensor completion problem, which has achieved state-of-the-art performance on image and video inpainting tasks. However, it requires computing tensor singular value decomposition (t-SVD), which costs much computation and thus cannot efficiently handle tensor data, due to its natural large scale. Motivated by TNN, we propose a novel low-rank tensor factorization method for efficiently solving the 3-way tensor completion problem. Our method preserves the low-rank structure of a tensor by factorizing it into the product of two tensors of smaller sizes. In the optimization process, our method only needs to update two smaller tensors, which can be more efficiently conducted than computing t-SVD. Furthermore, we prove that the proposed alternating minimization algorithm can converge to a Karush-Kuhn-Tucker point. Experimental results on the synthetic data recovery, image and video inpainting tasks clearly demonstrate the superior performance and efficiency of our developed method over state-of-the-arts including the TNN and matricization methods.

Spatial and temporal patterns of debris flow deposition in the Oregon Coast Range, USA

USGS Publications Warehouse

May, Christine L.; Gresswell, Robert E.

2004-01-01

Patterns of debris-flow occurrence were investigated in 125 headwater basins in the Oregon Coast Range. Time since the previous debris-flows was established using dendrochronology, and recurrence interval estimates ranged from 98 to 357 years. Tributary basins with larger drainage areas had a greater abundance of potential landslide source areas and a greater frequency of scouring events compared to smaller basins. The flux rate of material delivered to the confluence with a larger river influenced the development of small-scale debris-flow fans. Fans at the mouths of tributary basins with smaller drainage areas had a higher likelihood of being eroded by the mainstem river in the interval between debris-flows, compared to bigger basins that had larger, more persistent fans. Valley floor width of the receiving channel also influenced fan development because it limited the space available to accommodate fan formation. Of 63 recent debris-flows, 52% delivered sediment and wood directly to the mainstem river, 30% were deposited on an existing fan before reaching the mainstem, and 18% were deposited within the confines of the tributary valley before reaching the confluence. Spatial variation in the location of past and present depositional surfaces indicated that sequential debris-flow deposits did not consistently form in the same place. Instead of being spatially deterministic, results of this study suggest that temporally variable and stochastic factors may be important for predicting the runout length of debris-flows.

Effects of etching time on alpha tracks in solid state nuclear track detectors.

PubMed

Gillmore, Gavin; Wertheim, David; Crust, Simon

2017-01-01

Solid State Nuclear Track Detectors (SSNTDs) are used extensively for monitoring alpha particle radiation, neutron flux and cosmic ray radiation. Radon gas inhalation is regarded as being a significant contributory factor to lung cancer deaths in the UK each year. Gas concentrations are often monitored using CR39 based SSNTDs as the natural decay of radon results in alpha particles which form tracks in these detectors. Such tracks are normally etched for about 4h to enable microscopic analysis. This study examined the effect of etching time on the appearance of alpha tracks in SSNTDs by collecting 2D and 3D image datasets using laser confocal microscope imaging techniques. Etching times of 2 to 4h were compared and marked differences were noted in resultant track area. The median equivalent diameters of tracks were 20.2, 30.2 and 38.9μm for etching at 2, 3 and 4h respectively. Our results indicate that modern microscope imaging can detect and image the smaller size tracks seen for example at 3h etching time. Shorter etching times may give rise to fewer coalescing tracks although there is a balance to consider as smaller track sizes may be more difficult to image. Thus etching for periods of less than 4h clearly merits further investigation as this approach has the potential to improve accuracy in assessing the number of tracks. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationship between the caregiver's report on the patient's spontaneous-speech and the Brief Aphasia Evaluation.

PubMed

Vigliecca, Nora Silvana

2017-11-09

To study the relationship between the caregiver's perception about the patient's impairment in spontaneous speech, according to an item of four questions administered by semi-structured interview, and the patient's performance in the Brief Aphasia Evaluation (BAE). 102 right-handed patients with focal brain lesions of different types and location were examined. BAE is a valid and reliable instrument to assess aphasia. The caregiver's perception was correlated with the item of spontaneous speech, the total score and the three main factors of the BAE: Expression, Comprehension and Complementary factors. The precision (sensitivity/ specificity) about the caregiver's perception of the patient's spontaneous speech was analyzed with reference to the presence or absence of disorder, according to the professional, on the BAE item of spontaneous speech. The studied correlation was satisfactory, being greater (higher than 80%) for the following indicators: the item of spontaneous speech, the Expression factor and the total score of the scale; the correlation was a little smaller (higher than 70%) for the Comprehension and Complementary factors. Comparing two cut-off points that evaluated the precision of the caregiver's perception, satisfactory results were observed in terms of sensitivity and specificity (>70%) with likelihood ratios higher than three. By using the median as the cut-off point, more satisfactory diagnostic discriminations were obtained. Interviewing the caregiver specifically on the patient's spontaneous speech, in an abbreviated form, provides relevant information for the aphasia diagnosis.

Caught in the Act: Gas and Stellar Velocity Dispersions in a Fast Quenching Compact Star-Forming Galaxy at z~1.7

NASA Astrophysics Data System (ADS)

Barro, Guillermo; Faber, Sandra M.; Dekel, Avishai; Pacifici, Camilla; Pérez-González, Pablo G.; Toloba, Elisa; Koo, David C.; Trump, Jonathan R.; Inoue, Shigeki; Guo, Yicheng; Liu, Fengshan; Primack, Joel R.; Koekemoer, Anton M.; Brammer, Gabriel; Cava, Antonio; Cardiel, Nicolas; Ceverino, Daniel; Eliche, Carmen; Fang, Jerome J.; Finkelstein, Steven L.; Kocevski, Dale D.; Livermore, Rachael C.; McGrath, Elizabeth

2016-04-01

We present Keck I MOSFIRE spectroscopy in the Y and H bands of GDN-8231, a massive, compact, star-forming galaxy at a redshift of z ˜ 1.7. Its spectrum reveals both Hα and [N II] emission lines and strong Balmer absorption lines. The Hα and Spitzer MIPS 24 μm fluxes are both weak, thus indicating a low star-formation rate of SFR ≲ 5{--}10 {M}⊙ yr-1. This, added to a relatively young age of ˜700 Myr measured from the absorption lines, provides the first direct evidence for a distant galaxy being caught in the act of rapidly shutting down its star formation. Such quenching allows GDN-8231 to become a compact, quiescent galaxy, similar to three other galaxies in our sample, by z ˜ 1.5. Moreover, the color profile of GDN-8231 shows a bluer center, consistent with the predictions of recent simulations for an early phase of inside-out quenching. Its line-of-sight velocity dispersion for the gas, {σ }{{{LOS}}}{{gas}} = 127 ± 32 km s-1, is nearly 40% smaller than that of its stars, {σ }{{{LOS}}}\\star = 215 ± 35 km s-1. High-resolution hydro-simulations of galaxies explain such apparently colder gas kinematics of up to a factor of ˜1.5 with rotating disks being viewed at different inclinations and/or centrally concentrated star-forming regions. A clear prediction is that their compact, quiescent descendants preserve some remnant rotation from their star-forming progenitors.

Effectiveness and cost of different strategies for information feedback in general practice.

PubMed Central

Szczepura, A; Wilmot, J; Davies, C; Fletcher, J

1994-01-01

AIM. The aim of this study was to determine the effectiveness and relative cost of three forms of information feedback to general practices--graphical, graphical plus a visit by a medical facilitator and tabular. METHOD. Routinely collected, centrally-held data were used where possible, analysed at practice level. Some non-routine practice data in the form of risk factor recording in medical notes, for example weight, smoking status, alcohol consumption and blood pressure, were also provided to those who requested it. The 52 participating practices were stratified and randomly allocated to one of the three feedback groups. The cost of providing each type of feedback was determined. The immediate response of practitioners to the form of feedback (acceptability), ease of understanding (intelligibility), and usefulness of regular feedback was recorded. Changes introduced as a result of feedback were assessed by questionnaire shortly after feedback, and 12 months later. Changes at the practice level in selected indicators were also assessed 12 and 24 months after initial feedback. RESULTS. The resulting cost per effect was calculated to be 46.10 pounds for both graphical and tabular feedback, 132.50 pounds for graphical feedback plus facilitator visit and 773.00 pounds for the manual audit of risk factors recorded in the practice notes. The three forms of feedback did not differ in intelligibility or usefulness, but feedback plus a medical facilitator visit was significantly less acceptable. There was a high level of self-reported organizational change following feedback, with 69% of practices reporting changes as a direct result; this was not significantly different for the three types of feedback. There were no significant changes in the selected indicators at 12 or 24 months following feedback. The practice characteristic most closely related to better indicators of preventive practice was practice size, smaller practices performing significantly better. Separate clinics were not associated with better preventive practice. CONCLUSION. It is concluded that feedback strategies using graphical and tabular comparative data are equally cost-effective in general practice with about two thirds of practices reporting organizational change as a consequence; feedback involving unsolicited medical facilitator visits is less cost-effective. The cost-effectiveness of manual risk factor audit is also called into question. PMID:8312032

Nucleation of stoichiometric compounds from liquid: Role of the kinetic factor

NASA Astrophysics Data System (ADS)

Song, H.; Sun, Y.; Zhang, F.; Wang, C. Z.; Ho, K. M.; Mendelev, M. I.

2018-02-01

The nucleation rate depends on the free-energy barrier and the kinetic factor. While the role of the free energy barrier is a text-book subject, the importance of the kinetic factor is frequently underestimated. In this study, we applied the mean first-passage time method, to obtain the free-energy landscape and kinetic factor directly from the molecular dynamics (MD) simulations of the nucleation of the face-centered cubic (fcc) phase in the pure Ni and the B2 phases in the N i50A l50 and C u50Z r50 alloys. The obtained data show that while the free-energy barrier for nucleation is higher in pure Ni the nucleation rate is considerably lower in the N i50A l50 alloy. This result can be explained by the slow attachment kinetics in the N i50A l50 alloy, which was related to the ordered nature of the B2 phase. Even smaller fraction of the antisite defects in the C u50Z r50 alloy leads to such a slow attachment kinetics that the nucleation is never observed for this alloy in the course of the MD simulation. This is consistent with the experimental facts that the C u50Z r50 alloy is a good glass forming alloy and the N i50A l50 alloy is not. Thus the present study demonstrates that the atom attachment rate can be the critical factor that controls the nucleation process under certain conditions.

Learning Approaches and Lecture Attendance of Medical Students

ERIC Educational Resources Information Center

Bates, Madeleine; Curtis, Sally; Dismore, Harriet

2018-01-01

There are arguably many factors that affect the way a student learns. A recent report by the Higher Education Policy Institute (HEPI) and the Higher Education Academy (HEA) on student academic experience in the UK states that class size is an important factor in the quality of the student experience and that smaller class sizes provide greater…

Risk Factors for Behavioral and Emotional Difficulties in Siblings of Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Walton, Katherine M.

2016-01-01

This study examined risk factors for behavioral and emotional problems in 1973 siblings of children with autism spectrum disorders (ASD). Results revealed six correlates of sibling internalizing and externalizing problems: male gender, smaller family size, older age of the child with ASD, lower family income, child with ASD behavior problems, and…

Factor Structure of the Hare Psychopathy Checklist: Youth Version (PCL: YV) in Adolescent Females

ERIC Educational Resources Information Center

Kosson, David S.; Neumann, Craig S.; Forth, Adelle E.; Salekin, Randall T.; Hare, Robert D.; Krischer, Maya K.; Sevecke, Kathrin

2013-01-01

Despite substantial evidence for the fit of the 3- and 4-factor models of Psychopathy Checklist-based ratings of psychopathy in adult males and adolescents, evidence is less consistent in adolescent females. However, prior studies used samples much smaller than recommended for examining model fit. To address this issue, we conducted a confirmatory…

21 CFR 74.2101 - FD&C Blue No. 1.

Code of Federal Regulations, 2012 CFR

2012-04-01

...-[(ethylphenylamino)methyl] benzenesulfonic acid, and smaller amounts of 4-[(ethylphenylamino)methyl] benzenesulfonic acid and 2-[(ethylphenylamino)methyl] benzenesulfonic acid to form the leuco base. The leuco base is... inner salt. Additionally, FD&C Blue No. 1 is manufactured by the acid catalyzed condensation of one mole...

21 CFR 74.2101 - FD&C Blue No. 1.

Code of Federal Regulations, 2013 CFR

2013-04-01

...-[(ethylphenylamino)methyl] benzenesulfonic acid, and smaller amounts of 4-[(ethylphenylamino)methyl] benzenesulfonic acid and 2-[(ethylphenylamino)methyl] benzenesulfonic acid to form the leuco base. The leuco base is... inner salt. Additionally, FD&C Blue No. 1 is manufactured by the acid catalyzed condensation of one mole...

21 CFR 74.2101 - FD&C Blue No. 1.

Code of Federal Regulations, 2014 CFR

2014-04-01

...-[(ethylphenylamino)methyl] benzenesulfonic acid, and smaller amounts of 4-[(ethylphenylamino)methyl] benzenesulfonic acid and 2-[(ethylphenylamino)methyl] benzenesulfonic acid to form the leuco base. The leuco base is... inner salt. Additionally, FD&C Blue No. 1 is manufactured by the acid catalyzed condensation of one mole...

78 FR 54722 - Reports, Forms and Record Keeping Requirements

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

... submission requesting confidential treatment. This estimate will vary based on the size of the submission, with smaller and voluntary submissions taking considerably less time to prepare. The agency based this... approximately 460 requests for confidential treatment annually. This figure is based on the average number of...

Establishing criteria for human mesenchymal stem cell potency.

PubMed

Samsonraj, Rebekah M; Rai, Bina; Sathiyanathan, Padmapriya; Puan, Kia Joo; Rötzschke, Olaf; Hui, James H; Raghunath, Michael; Stanton, Lawrence W; Nurcombe, Victor; Cool, Simon M

2015-06-01

This study sought to identify critical determinants of mesenchymal stem cell (MSC) potency using in vitro and in vivo attributes of cells isolated from the bone marrow of age- and sex-matched donors. Adherence to plastic was not indicative of potency, yet capacity for long-term expansion in vitro varied considerably between donors, allowing the grouping of MSCs from the donors into either those with high-growth capacity or low-growth capacity. Using this grouping strategy, high-growth capacity MSCs were smaller in size, had greater colony-forming efficiency, and had longer telomeres. Cell-surface biomarker analysis revealed that the International Society for Cellular Therapy (ISCT) criteria did not distinguish between high-growth capacity and low-growth capacity MSCs, whereas STRO-1 and platelet-derived growth factor receptor alpha were preferentially expressed on high-growth capacity MSCs. These cells also had the highest mean expression of the mRNA transcripts TWIST-1 and DERMO-1. Irrespective of these differences, both groups of donor MSCs produced similar levels of key growth factors and cytokines involved in tissue regeneration and were capable of multilineage differentiation. However, high-growth capacity MSCs produced approximately double the volume of mineralized tissue compared to low-growth capacity MSCs when assessed for ectopic bone-forming ability. The additional phenotypic criteria presented in this study when combined with the existing ISCT minimum criteria and working proposal will permit an improved assessment of MSC potency and provide a basis for establishing the quality of MSCs prior to their therapeutic application. © 2015 AlphaMed Press.

Establishing Criteria for Human Mesenchymal Stem Cell Potency

PubMed Central

Samsonraj, Rebekah M.; Rai, Bina; Sathiyanathan, Padmapriya; Puan, Kia Joo; Rötzschke, Olaf; Hui, James H.; Raghunath, Michael; Stanton, Lawrence W.; Nurcombe, Victor

2015-01-01

Abstract This study sought to identify critical determinants of mesenchymal stem cell (MSC) potency using in vitro and in vivo attributes of cells isolated from the bone marrow of age‐ and sex‐matched donors. Adherence to plastic was not indicative of potency, yet capacity for long‐term expansion in vitro varied considerably between donors, allowing the grouping of MSCs from the donors into either those with high‐growth capacity or low‐growth capacity. Using this grouping strategy, high‐growth capacity MSCs were smaller in size, had greater colony‐forming efficiency, and had longer telomeres. Cell‐surface biomarker analysis revealed that the International Society for Cellular Therapy (ISCT) criteria did not distinguish between high‐growth capacity and low‐growth capacity MSCs, whereas STRO‐1 and platelet‐derived growth factor receptor alpha were preferentially expressed on high‐growth capacity MSCs. These cells also had the highest mean expression of the mRNA transcripts TWIST‐1 and DERMO‐1. Irrespective of these differences, both groups of donor MSCs produced similar levels of key growth factors and cytokines involved in tissue regeneration and were capable of multilineage differentiation. However, high‐growth capacity MSCs produced approximately double the volume of mineralized tissue compared to low‐growth capacity MSCs when assessed for ectopic bone‐forming ability. The additional phenotypic criteria presented in this study when combined with the existing ISCT minimum criteria and working proposal will permit an improved assessment of MSC potency and provide a basis for establishing the quality of MSCs prior to their therapeutic application. Stem Cells 2015;33:1878–1891 PMID:25752682

Grafting of ARPE-19 and Schwann cells to the subretinal space in RCS rats.

PubMed

Wang, Shaomei; Lu, Bin; Wood, Patrick; Lund, Raymond D

2005-07-01

To study the distribution of the human retinal pigment epithelium (hRPE) cell line ARPE-19 and human Schwann (hSC) cells grafted to the subretinal space of the Royal College of Surgeon (RCS) rat and the relation of graft cell distribution to photoreceptor rescue. Cell suspensions of both donor types were injected into the subretinal space of 3-week-old dystrophic RCS rats through a transscleral approach, human fibroblast and medium were used as control grafts. All animals were maintained on oral cyclosporine. At 1, 2, 4, 6, 15, 28, and 36 weeks after grafting, animals were killed. Human cell-specific markers were used to localize donor cells. Both donor cell types, as revealed by antibodies survived for a substantial time. Their distribution was very different: hRPE cells formed a large clump early on and, with time, spread along the host RPE in a layer one to two cells deep, whereas hSCs formed many smaller clumps, mainly in the subretinal space. Both cells rescued photoreceptors beyond the area of donor cell distribution. The number of surviving cells declined with time. Both hRPE and hSC grafts can survive and rescue photoreceptors for a substantial time after grafting. The number of both donor cell types declined with time, which could be an immune-related problem and/or due to other factors intrinsic to the host RCS retina. The fact that rescue occurred beyond the area of donor cell distribution suggests that diffusible factors are involved, raising the possibility that the two cell types function in a similar manner to rescue photoreceptors.

Ion-molecule condensation reactions: a mechanism for organic synthesis in ionized reducing atmospheres.

PubMed

Meot-Ner, M

1978-12-01

The CH3+ ion, formed in ionized methane, undergoes consecutive eliminative condensation reactions with methane to form the carbonium ions C2H5+, i-C3H7+ and t-C4H9+. At T smaller than 500 degrees K, NCH4 greater than 10(16) cm-3 these ions react with NH3 in competitive condensation -- H+ transfer reactions, e.g. C2H5 + NH3 M leads to C2H5NH3+ leads to NH4+ + C2H4 At particle densities of NCH4 smaller than 10(16) cm-3 proton transfer is the only significant reaction channel. At NCH4 greater than 10(17) cm-3 condensation constitutes 5--20% of the overall reactions. The product of the condensation reaction further associates with CO2 to form C2H5NH3+ . CO2; the atomic composition of this cluster ion is identical with the protonated amino acid alanine. The carbonium ions i-C3H7+ and t-C4H9+ condense also with HCN to yield protonated isocyanides. HCNH% also appears to condense with HCN at T greater than 570 degrees K, and form cluster ions with HCN at lower temperatures. The rate constants of the condensation reactions vary with temperature and pressure in a complex manner. Under conditions similar to those on Titan at an altitude of 100 km (T = 100--150 degrees K, NCH4 approximately 10(18) cm-3), with a methane atmosphere containing 1% H2 and traces of NH3 and H2O, ion-molecule condensation reactions followed by H+ transfer are expected to lead to the atmospheric synthesis of C2H6, C3H8, CH3OH, C2H5OH and the terminal ions NH4+, CH3NH3+ and C2H5NH3+. At higher temperatures (250 degrees K smaller than T smaller than 400 degrees K), the synthesis of i-C4H10, i-C3H7OH and t-C4H9OH and of the ions i-C3H7NH3+ and t-C4H9NH3+ is also expected. Electron recombination of the terminal ions may yield amines, imines and nitriles. Cycles of protonation and dissociative recombination of the alkanes and alcohols produced in condensation reactions will also produce unsaturated hydrocarbons, ketones and aldehydes in the ionized atmosphere.

Mathematical treatment of isotopologue and isotopomer speciation and fractionation in biochemical kinetics

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

Maggi, F.M.; Riley, W.J.

2009-11-01

We present a mathematical treatment of the kinetic equations that describe isotopologue and isotopomer speciation and fractionation during enzyme-catalyzed biochemical reactions. These equations, presented here with the name GEBIK (general equations for biochemical isotope kinetics) and GEBIF (general equations for biochemical isotope fractionation), take into account microbial biomass and enzyme dynamics, reaction stoichiometry, isotope substitution number, and isotope location within each isotopologue and isotopomer. In addition to solving the complete GEBIK and GEBIF, we also present and discuss two approximations to the full solutions under the assumption of biomass-free and enzyme steady-state, and under the quasi-steady-state assumption as applied tomore » the complexation rate. The complete and approximate approaches are applied to observations of biological denitrification in soils. Our analysis highlights that the full GEBIK and GEBIF provide a more accurate description of concentrations and isotopic compositions of substrates and products throughout the reaction than do the approximate forms. We demonstrate that the isotopic effects of a biochemical reaction depend, in the most general case, on substrate and complex concentrations and, therefore, the fractionation factor is a function of time. We also demonstrate that inverse isotopic effects can occur for values of the fractionation factor smaller than 1, and that reactions that do not discriminate isotopes do not necessarily imply a fractionation factor equal to 1.« less

The effects of food level and conspecific density on biting and cannibalism in larval long-toed salamanders, Ambystoma macrodactylum.

PubMed

Wildy, Erica L; Chivers, Douglas P; Kiesecker, Joseph M; Blaustein, Andrew R

2001-07-01

Previous studies have examined abiotic and biotic factors that facilitate agonistic behavior. For larval amphibians, food availability and conspecific density have been suggested as important factors influencing intraspecific aggression and cannibalism. In this study, we examined the separate and combined effects of food availability and density on the agonistic behavior and life history of larval long-toed salamanders, Ambystoma macrodactylum. We designed a 2×2 factorial experiment in which larvae were raised with either a high or low density of conspecifics and fed either a high or low level of food. For each treatment, we quantified the amount of group size variation, biting, and cannibalism occurring. Additionally, we examined survival to, time to and size at metamorphosis for all larvae. Results indicated that differences in both density and food level influenced all three life history traits measured. Moreover, differences in food level at which larvae were reared resulted in higher within-group size variation and heightened intraspecific biting while both density and food level contributed to increased cannibalism. We suggest that increased hunger levels and an uneven size structure promoted biting among larvae in the low food treatments. Moreover, these factors combined with a higher encounter rate with conspecifics in the high density treatments may have prompted larger individuals to seek an alternative food source in the form of smaller conspecifics.

Evaluation of Factors Affecting Powdered Drug Reconstitution in Microgravity

NASA Technical Reports Server (NTRS)

Schaffner, Grant; Johnston, Smith; Marshburn, Tom

1999-01-01

Owing to the high cost of transporting mass into space, and the small volume available for equipment in the Space Shuttle Orbiter and the International Space Station, refrigeration space is extremely limited. For this reason, there exists strong motivation for transporting certain drugs in powdered form so that they do not require refrigeration. When needed, the powdered drug will be mixed with saline to obtain a liquid form that may be injected intravenously. While this is a relatively simple task in a 1-G environment, there are some difficulties that may be encountered in 0-G. In non-accelerated spaceflight, gravitational and inertial forces are eliminated allowing other smaller forces, such as capillary forces and surface tension, to dominate the behavior of fluids. For instance, water slowly ejected from a straw will tend to form a sphere, while fluid in a container will tend to wet the inside surface forming a highly rounded meniscus. Initial attempts at mixing powdered drugs with saline in microgravity have shown a tendency toward forming foamy emulsions instead of the desired homogeneous solution. The predominance of adhesive forces between the drug particles and the interface tensions at the gas/liquid and solid/liquid interfaces drastically reduce the rate of deaggregation of the drug powder and also reduce the rate of absorption of saline by the powder mass. In addition, the capillary forces cause the saline to wet the inside of the container, thus trapping air bubbles within the liquid. The rate of dissolution of a powder drug is directly proportional to the amount of surface area of the solid that is exposed to liquid solvent. The surface area of drug that is in contact with the liquid is greatly reduced in microgravity and, as a result, the dissolution rate is reduced as well. The KC-135 research described here was aimed at evaluating the extent to which it is possible to perform drug reconstitution in the weightlessness of parabolic flight using standard pharmacological supplies. The experiment included a parametric assessment of possible factors affecting the reconstitution process. The specific questions that we wished to answer were: (1) Is it possible to reconstitute powdered drugs in weightlessness using standard pharmacological equipment? (2) What are the differences between drug reconstitution in a 1-G and a 0-G environment? (3) What techniques of mixing the drug powder and diluent are more successful? (4) What physical and chemical factors play a role in determining the success of mixing and dissolution? (5) Is it necessary to employ crewmember and equipment restraints during the reconstitution process?

Cysteine reacts to form blue-green pigments with thiosulfinates obtained from garlic (Allium sativum L.).

PubMed

Shin, Young Keum; Kyung, Kyu Hang

2014-01-01

Cysteine was found to form pigments with garlic thiosulfinates in this investigation, in contrast to previous reports. Pigments were formed only when the molar concentration ratios of cysteine to total thiosulfinates were smaller than 2:1. Cysteine does not form pigments with thiosulfinates in the same manner as other pigment-forming amino compounds because it has a sulfhydryl (SH) group. A colour reaction of cysteine with thiosulfinates is proposed where colourless disulphide-type S-alk(en)yl mercaptocysteines (SAMCs) are formed first by the SH-involved reaction between cysteine and thiosulfinates, and then SAMCs react with residual thiosulfinates to form pigments. When the cysteine to total thiosulfinate molar concentration ratio was 2:1 or greater, total thiosulfinates were consumed to form SAMCs without leaving any thiosulfinates remaining available for the following colour reactions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Retinal vessel caliber among people with acquired immunodeficiency syndrome: relationships with disease-associated factors and mortality.

PubMed

Gangaputra, Sapna; Kalyani, Partho S; Fawzi, Amani A; Van Natta, Mark L; Hubbard, Larry D; Danis, Ronald P; Thorne, Jennifer E; Holland, Gary N

2012-03-01

To evaluate relationships between retinal vessel caliber, AIDS-related factors, and mortality. Longitudinal, observational cohort study. We evaluated data for participants without ocular opportunistic infections at initial examination (baseline) in the Longitudinal Studies of the Ocular Complications of AIDS (1998-2008). Semi-automated evaluation of fundus photographs (1 eye/participant) determined central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and arteriole-to-venule ratio (AVR) at baseline. Multiple linear regression models, using forward selection, identified independent relationships between indices and various host- and disease-related variables. Included were 1250 participants. Mean follow-up for determination of mortality was 6.1 years. Smaller CRAE was related to increased age (P < .001) and hypertension (P < .001); larger CRAE was related to lower hematocrit (P = .002). Larger CRAE and CRVE were associated with black race (P < .001). Larger CRVE was related to smoking (P = .004); smaller CRVE was related to age (P < .001) and higher mean corpuscular volume (P = .001). We observed the following relationships with AIDS-associated factors: smaller CRAE and larger CRVE with history of highly active antiretroviral therapy (HAART; P < .001); and larger CRAE with lower CD4+ T lymphocyte count (P = .04). We did not identify independent relationships with human immunodeficiency virus RNA blood levels. There was a 12% (95% CI, 2%-21%) increase in mortality risk per quartile of decreasing AVR (P = .02). Variations in retinal vascular caliber are associated with AIDS-specific factors and are markers for increased mortality risk. Relationships are consistent with the hypothesis that the vasculature is altered by known atherogenic effects of chronic HAART or the prolonged inflammatory state associated with AIDS. Copyright © 2012 Elsevier Inc. All rights reserved.

Nursing staff turnover at a Swedish university hospital: an exploratory study.

PubMed

Sellgren, Stina F; Kajermo, Kerstin N; Ekvall, Göran; Tomson, Göran

2009-11-01

The aim was to explore opinions on individual needs and other factors that may influence nursing staff turnover. High staff turnover is a great problem for many hospitals. It is shown to have a negative effect on the quality of nursing care and to increase hospital costs. In 2004 in a large university hospital in Sweden five focus group discussions (FGDs) including department heads (1), nursing managers (2) and members of nursing staff (2) were carried out. The questions to be addressed were 'Why do nurses leave?' and 'Why do nurses stay?' In addition, register data of staff turnover for 2002-2003 were analysed in relation to different facts about the units, such as number of employees, type of care and medical specialty. Categories of opinions identified in the FGDs were compared with results of the statistical analyses on the relationship between staff turnover and unit parameters to identify overall factors that may influence on nurse staff turnover. Four major factors were identified as having a possible influence on staff turnover: 'intrinsic values of motivation', 'work load', 'unit size 'and 'leadership'. Smaller units had lower staff turnover as well as outpatient units and day care. It was not possible to compare statements from participants from smaller units with those from participants from larger units. Two factors had diverging data, 'salary' and 'spirit of the time'. A surprising finding was the little mention of patient care in relation to staff turnover. It is important for managers to ensure that intrinsic values of nurses are met to minimise the risk for high turnover rates. Inpatient care must receive adequate staffing and nursing care could be organised into smaller units or work teams to avoid dissatisfaction and high turnover.

Basic Characteristics of Laser Heating in Thermoluminescence and of Laser-Stimulated Luminescence

DTIC Science & Technology

1990-07-15

as examples. These include LiF:Mg,Ti ( TLD -100, Harshaw Chemical Corporation) in form of chips, which are widely used in the dosimetry of ionizing...take dosimetry ( TLD ) of ionizing radiation because it holds pro- the form of discrete circular spots whose diameter is smaller mise as a solution to...function of typical phosphor, we choose the most widely used dosimetry time after onset of the laser exposure, the time-dependent material LiF:Mg,Ti ( TLD

Harry S. Truman Dam and Reservoir, Missouri: Ice Age Climates: Plants and Animals of Western Missouri: A 50,000 Year Records of Change.

DTIC Science & Technology

1983-01-01

and large but, relative to former times, smaller forms of bison inhab- ited western Missouri at this time. The known or inferred habitat prefer...Sabertooth, like the modern *. lion, formed prides to better stalk prey in open habitats . Though this is the first record of the Sabertooth from western...water requirements, onagers are better suited to more rigorous habitats than are other species of horses. Based on specimens recovered from Jones Spring

17 CFR 210.8-08 - Age of financial statements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 17 Commodity and Securities Exchanges 2 2011-04-01 2011-04-01 false Age of financial statements. 210.8-08 Section 210.8-08 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION FORM... Smaller Reporting Companies § 210.8-08 Age of financial statements. At the date of filing, financial...

A Primer on An Approach to Planning and Production Control for the Smaller Shipyard

DTIC Science & Technology

1983-12-01

experienced estimators. ● Hours are allocated to individual jobs within a project for larger projects only. Return costs are then reviewed against these... UNIVERSELLES ANALYSIER SYSTEMS 4-17 h. Published Literature There are extensive standard data available quantities of engineered in published form. The

Sensitivities of Soap Solutions in Leak Detection

NASA Technical Reports Server (NTRS)

Stuck, D.; Lam, D. Q.; Daniels, C.

1985-01-01

Document describes method for determining minimum leak rate to which soap-solution leak detectors sensitive. Bubbles formed at smaller leak rates than previously assumed. In addition to presenting test results, document discusses effects of joint-flange configurations, properties of soap solutions, and correlation of test results with earlier data.

40 CFR 63.5460 - What definitions apply to this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... combination of smaller leather pieces and leather fibers, which when joined together, form an integral..., thus, cannot withstand 5,000 Maeser Flexes with a Maeser Flex Testing Machine or a method approved by... Maeser Flex Testing Machine or a method approved by the Administrator prior to initial water penetration...

40 CFR 63.5460 - What definitions apply to this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... combination of smaller leather pieces and leather fibers, which when joined together, form an integral..., thus, cannot withstand 5,000 Maeser Flexes with a Maeser Flex Testing Machine or a method approved by... Maeser Flex Testing Machine or a method approved by the Administrator prior to initial water penetration...

40 CFR 63.5460 - What definitions apply to this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... combination of smaller leather pieces and leather fibers, which when joined together, form an integral..., thus, cannot withstand 5,000 Maeser Flexes with a Maeser Flex Testing Machine or a method approved by... Maeser Flex Testing Machine or a method approved by the Administrator prior to initial water penetration...

How to form planetesimals from mm-sized chondrules and chondrule aggregates

NASA Astrophysics Data System (ADS)

Carrera, Daniel; Johansen, Anders; Davies, Melvyn B.

2015-07-01

The size distribution of asteroids and Kuiper belt objects in the solar system is difficult to reconcile with a bottom-up formation scenario due to the observed scarcity of objects smaller than ~100 km in size. Instead, planetesimals appear to form top-down, with large 100-1000 km bodies forming from the rapid gravitational collapse of dense clumps of small solid particles. In this paper we investigate the conditions under which solid particles can form dense clumps in a protoplanetary disk. We used a hydrodynamic code to model the interaction between solid particles and the gas inside a shearing box inside the disk, considering particle sizes from submillimeter-sized chondrules to meter-sized rocks. We found that particles down to millimeter sizes can form dense particle clouds through the run-away convergence of radial drift known as the streaming instability. We made a map of the range of conditions (strength of turbulence, particle mass-loading, disk mass, and distance to the star) that are prone to producing dense particle clumps. Finally, we estimate the distribution of collision speeds between mm-sized particles. We calculated the rate of sticking collisions and obtain a robust upper limit on the particle growth timescale of ~105 years. This means that mm-sized chondrule aggregates can grow on a timescale much smaller than the disk accretion timescale (~106-107 years). Our results suggest a pathway from the mm-sized grains found in primitive meteorites to fully formed asteroids. We speculate that asteroids may form from a positive feedback loop in which coagualation leads to particle clumping driven by the streaming instability. This clumping, in turn, reduces collision speeds and enhances coagulation. Future simulations should model coagulation and the streaming instability together to explore this feedback loop further. Appendices are available in electronic form at http://www.aanda.org

A Frost Enhanced Landscape

NASA Image and Video Library

2015-12-23

The arc of hills in this image from NASA Mars Reconnaissance Orbiter spacecraft is the rim of an old and infilled impact crater. The sediments that were deposited within the crater have since formed polygonal cracks due to repeated cycles of freezing and thawing. The process of polygon formation is common at these polar latitudes, but polygons are not always as striking as they are here. In this image, the polygons have been highlighted by persistent frost in the cracks. The crater rim constrains the polygon formation within the crater close to the rim, creating a spoke and ring pattern of cracks. This leads to more rectangular polygons than those near the center of the crater. The polygons close to the center of the crater display a more typical pattern. A closer look shows some of these central polygons, which have smaller polygons within them, and smaller polygons within those smaller polygons, which makes for a natural fractal. http://photojournal.jpl.nasa.gov/catalog/PIA20289

Neopterin formation and tryptophan degradation by a human myelomonocytic cell line (THP-1) upon cytokine treatment.

PubMed

Werner-Felmayer, G; Werner, E R; Fuchs, D; Hausen, A; Reibnegger, G; Wachter, H

1990-05-15

Determination of neopterin [D-erythro-6-(1',2',3'-trihydroxypropyl)pterin] in body fluids is a powerful diagnostic tool in a variety of diseases in which activation of cellular immune mechanisms is involved, such as certain malignancies, allograft rejection, and autoimmune and infectious diseases. In vitro, neopterin is released into the supernatant by peripheral blood-derived monocytes/macrophages upon stimulation with gamma-interferon. In parallel, cleavage of tryptophan by indoleamine 2,3-dioxygenase is induced. We report here that the human myelomonocytic cell line THP-1 forms neopterin and degrades tryptophan upon treatment with gamma-interferon. Like in macrophages alpha-interferon and beta-interferon induce these pathways only to a much smaller degree. The action of interferons is enhanced by cotreatment with tumor necrosis factor alpha, lipopolysaccharide, or dexamethasone. gamma-Interferon-induced neopterin formation and indoleamine 2,3-dioxygenase activity are increased by raising extracellular tryptophan concentrations. The pattern of intracellularly formed pteridines upon stimulation with gamma-interferon shows the unique characteristics of human monocytes/macrophages. Neopterin, monapterin, and biopterin are produced in a 50:2:1 ratio. Thus, the THP-1 cell line provides a permanent, easily accessible in vitro system for studying the induction and mechanism of neopterin formation.

Hydrocarbon-Seeded Ignition System for Small Spacecraft Thrusters Using Ionic Liquid Propellants

NASA Technical Reports Server (NTRS)

Whitmore, Stephen A.; Merkley, Daniel P.; Eilers, Shannon D.; Taylor, Terry L.

2013-01-01

"Green" propellants based on Ionic-liquids (ILs) like Ammonium DiNitramide and Hydroxyl Ammonium Nitrate have recently been developed as reduced-hazard replacements for hydrazine. Compared to hydrazine, ILs offer up to a 50% improvement in available density-specific impulse. These materials present minimal vapor hazard at room temperature, and this property makes IL's potentially advantageous for "ride-share" launch opportunities where hazards introduced by hydrazine servicing are cost-prohibitive. Even though ILs present a reduced hazard compared to hydrazine, in crystalline form they are potentially explosive and are mixed in aqueous solutions to buffer against explosion. Unfortunately, the high water content makes IL-propellants difficult to ignite and currently a reliable "coldstart" capability does not exist. For reliable ignition, IL-propellants catalyst beds must be pre-heated to greater than 350 C before firing. The required preheat power source is substantial and presents a significant disadvantage for SmallSats where power budgets are extremely limited. Design and development of a "micro-hybrid" igniter designed to act as a "drop-in" replacement for existing IL catalyst beds is presented. The design requires significantly lower input energy and offers a smaller overall form factor. Unlike single-use "squib" pyrotechnic igniters, the system allows the gas generation cycle to be terminated and reinitiated on demand.

Influences of surface hydrophilicity on frost formation on a vertical cold plate under natural convection conditions

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

Liu, Zhongliang; Zhang, Xinghua; Wang, Hongyan

2007-07-15

Surface hydrophilicity has a strong influence on frost nucleation according to phase transition theory. To study this effect, a close observation of frost formation and deposition processes on a vertical plate was made under free convection conditions. The formation and shape variation of frost crystals during the initial period are described and the frost thickness variation with time on both hydrophobic and plain copper cold surfaces are presented. The various influencing factors are discussed in depth. The mechanism of surface hydrophilicity influence on frost formation was analyzed theoretically. This revealed that increasing the contact angle can increase the potential barriermore » and restrain crystal nucleation and growth and thus frost deposition. The experimental results show that the initial water drops formed on a hydrophobic surface are smaller and remain in the liquid state for a longer time compared with ones formed on a plain copper surface. It is also observed that the frost layer deposited on a hydrophobic surface is loose and weak. Though the hydrophobic surface can retard frost formation to a certain extent and causes a looser frost layer, our experimental results show that it does not depress the growth of the frost layer. (author)« less

Amyloid-like aggregates formation by bovine apo-carbonic anhydrase in various alcohols: A comparative study.

PubMed

Es-Haghi, Ali; Ebrahim-Habibi, Azadeh; Sabbaghian, Marjan; Nemat-Gorgani, Mohsen

2016-11-01

Peptides and proteins convert from their native states to amyloid fibrillar aggregates in a number of pathological conditions. Characterizing these species could provide useful information on their pathogenicity and the key factors involved in their generation. In this study, we have observed the ability of the model protein apo-bovine carbonic anhydrase (apo-BCA) to form amyloid-like aggregates in the presence of halogenated and non-halogenated alcohols. Far-UV circular dichroism, ThT fluorescence, atomic force microscopy and dynamic light scattering were used to characterize these structures. The concentration required for effective protein aggregation varied between the solvents, with non-halogenated alcohols acting in a wider range. These aggregates show amyloid-like structures as determined by specific techniques used for characterizing amyloid structures. Oligomers were obtained with various size distributions, but fibrillar structures were not observed. Use of halogenated alcohols resulted into smaller hydrodynamic radii, and most stable oligomers were formed in hexafluoropropan-2-ol (HFIP). At optimal concentrations used to generate these structures, the non-halogenated alcohols showed higher hydrophobicity, which may be related to the lower stability of the generated oligomers. These oligomers have the potential to be used as models in the search for effective treatments in proteinopathies. Copyright © 2016 Elsevier B.V. All rights reserved.

Synthesis, Crystal Structure, and Topology-Symmetry Analysis of a New Modification of NaIn[IO3]4

NASA Astrophysics Data System (ADS)

Belokoneva, E. L.; Karamysheva, A. S.; Dimitrova, O. V.; Volkov, A. S.

2018-01-01

Crystals of new iodate NaIn[IO3]4 were prepared by the hydrothermal synthesis. The unit cell parameters are a = 7.2672(2) Å, b = 15.2572(6) Å, c = 15.0208(6) Å, β = 101.517(3)°, sp. gr. P21/ c. The formula was determined during the structure determination and refinement of a twinned crystal based on a set of reflections from the atomic planes of the major individual. The refinement with anisotropic displacement parameters was performed for both twin components to the final R factor of 0.050. The In and Na atoms are in octahedral coordination formed by oxygen atoms. The oxygen octahedra are arranged into columns by sharing edges, and the columns are connected by isolated umbrella-like [IO3]- groups to form layers. The new structure is most similar to the isoformular iodate NaIn[IO3]4, which crystallizes in the same sp. gr. P21/ c and is structurally similar, but has a twice smaller unit cell and is characterized by another direction of the monoclinic axis. The structural similarity and difference between the two phases were studied by topologysymmetry analysis. The formation of these phases is related to different combinations of identical one-dimensional infinite chains of octahedra.

Family profile of victims of child abuse and neglect in the Kingdom of Saudi Arabia.

PubMed

Almuneef, Maha A; Alghamdi, Linah A; Saleheen, Hassan N

2016-08-01

To describe the family profile of child abuse and neglect (CAN) subjects in Saudi Arabia. Data were collected retrospectively between July 2009 and December 2013 from patients' files, which were obtained from the Child Protection Centre (CPC) based in King Abdulaziz Medical City, Riyadh, Saudi Arabia. Four main sets of variables were examined: demographics of victim, family profile, parental information, and information on perpetrator and forms of abuse.  The charts of 220 CAN cases were retrospectively reviewed. Physical abuse was the most common form of abuse (42%), followed by neglect (39%), sexual abuse (14%), and emotional abuse (4%). Children with unemployed fathers were 2.8 times as likely to experience physical abuse. Children living in single/step-parent households were 4 times as likely to experience physical abuse. Regarding neglect children living in larger households (≥6) were 1.5 times as likely to be neglected by their parents as were children living in smaller households (less than 6). Regarding sexual abuse, male children were 2.9 times as likely to be abused as were female children.  The recent acknowledgment of CAN as a public health problem in Saudi Arabia suggests that time will be needed to employ effective and culturally sensitive prevention strategies based on family risk factors.

Evidence for a near-Earth asteroid belt

NASA Technical Reports Server (NTRS)

Rabinowitz, D. L.; Gehrels, T.; Scotti, J. V.; Mcmillan, R. S.; Perry, M. L.; Wisniewski, W.; Larson, S. M.; Howell, E. S.; Mueller, B. E. A.

1993-01-01

In January 1991, the 0.9-m Spacewatch telescope made the first observation of an asteroid outside Earth's atmosphere but in the neighborhood of the Earth-moon system. Since then, more than 40 Earth-approaching asteroids have been discovered, including 13 smaller than 50 m. Using these data, one of us has shown that there is an excess of Earth-approaching asteroids with diameters less than 50 m, relative to the population inferred from the distribution of larger objects. Here we argue that these smaller objects - characterized by low eccentricities, widely ranging inclinations and unusual spectral properties - form a previously undetected asteroid belt concentrated near Earth. The recent discovery of additional small Earth-approaching asteroids supports this conclusion.

"Smaller Schools Are Good"...It Depends!

ERIC Educational Resources Information Center

Hill, Franklin

2001-01-01

Analyzes three high school sizes: 400-student "Private" school (small), 1,600-student school (medium), and 3,000-plus-student school (extra large). Uses four factors in comparative analysis: Equity, anonymity, program quality, and cost efficiency. (PKP)

Crater Mound Formation by Wind Erosion on Mars

NASA Astrophysics Data System (ADS)

Steele, L. J.; Kite, E. S.; Michaels, T. I.

2018-01-01

Most of Mars' ancient sedimentary rocks by volume are in wind-eroded sedimentary mounds within impact craters and canyons, but the connections between mound form and wind erosion are unclear. We perform mesoscale simulations of different crater and mound morphologies to understand the formation of sedimentary mounds. As crater depth increases, slope winds produce increased erosion near the base of the crater wall, forming mounds. Peak erosion rates occur when the crater depth is ˜2 km. Mound evolution depends on the size of the host crater. In smaller craters mounds preferentially erode at the top, becoming more squat, while in larger craters mounds become steeper sided. This agrees with observations where smaller craters tend to have proportionally shorter mounds and larger craters have mounds encircled by moats. If a large-scale sedimentary layer blankets a crater, then as the layer recedes across the crater it will erode more toward the edges of the crater, resulting in a crescent-shaped moat. When a 160 km diameter mound-hosting crater is subject to a prevailing wind, the surface wind stress is stronger on the leeward side than on the windward side. This results in the center of the mound appearing to "march upwind" over time and forming a "bat-wing" shape, as is observed for Mount Sharp in Gale crater.

The same frequency of planets inside and outside open clusters of stars.

PubMed

Meibom, Søren; Torres, Guillermo; Fressin, Francois; Latham, David W; Rowe, Jason F; Ciardi, David R; Bryson, Steven T; Rogers, Leslie A; Henze, Christopher E; Janes, Kenneth; Barnes, Sydney A; Marcy, Geoffrey W; Isaacson, Howard; Fischer, Debra A; Howell, Steve B; Horch, Elliott P; Jenkins, Jon M; Schuler, Simon C; Crepp, Justin

2013-07-04

Most stars and their planets form in open clusters. Over 95 per cent of such clusters have stellar densities too low (less than a hundred stars per cubic parsec) to withstand internal and external dynamical stresses and fall apart within a few hundred million years. Older open clusters have survived by virtue of being richer and denser in stars (1,000 to 10,000 per cubic parsec) when they formed. Such clusters represent a stellar environment very different from the birthplace of the Sun and other planet-hosting field stars. So far more than 800 planets have been found around Sun-like stars in the field. The field planets are usually the size of Neptune or smaller. In contrast, only four planets have been found orbiting stars in open clusters, all with masses similar to or greater than that of Jupiter. Here we report observations of the transits of two Sun-like stars by planets smaller than Neptune in the billion-year-old open cluster NGC6811. This demonstrates that small planets can form and survive in a dense cluster environment, and implies that the frequency and properties of planets in open clusters are consistent with those of planets around field stars in the Galaxy.

Undercuts by Laser Shock Forming

NASA Astrophysics Data System (ADS)

Wielage, Hanna; Vollertsen, Frank

2011-05-01

In laser shock forming TEA-CO2-laser induced shock waves are used to form metal foils, such as aluminum or copper. The process utilizes an initiated plasma shock wave on the target surface, which leads to a forming of the foil. A challenge in forming technologies is the manufacturing of undercuts. By conventional forming methods these special forms are not feasible. In this article, it is presented that undercuts in the micro range can be produced by laser shock deep drawing. Different drawing die diameters, drawing die depths and the material aluminum in the thicknesses 20 and 50 μm were investigated. It will be presented that smaller die diameters facilitate undercuts compared to bigger die diameters. The phenomena can be explained by Barlow's formula. Furthermore, it is shown which maximum undercut depth at different die diameters can be reached. To this end, cross-sections of the different parameter combinations are displayed.

LOW CO LUMINOSITIES IN DWARF GALAXIES

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

Schruba, Andreas; Walter, Fabian; Sandstrom, Karin

2012-06-15

We present maps of {sup 12}COJ = 2-1 emission covering the entire star-forming disks of 16 nearby dwarf galaxies observed by the IRAM HERACLES survey. The data have 13'' angular resolution, {approx}250 pc at our average distance of D = 4 Mpc, and sample the galaxies by 10-1000 resolution elements. We apply stacking techniques to perform the first sensitive search for CO emission in dwarf galaxies outside the Local Group ranging from individual lines of sight, stacking over IR-bright regions of embedded star formation, and stacking over the entire galaxy. We detect five galaxies in CO with total CO luminositiesmore » of L{sub CO2-1} = (3-28) Multiplication-Sign 10{sup 6} K km s{sup -1} pc{sup 2}. The other 11 galaxies remain undetected in CO even in the stacked images and have L{sub CO2-1} {approx}< (0.4-8) Multiplication-Sign 10{sup 6} K km s{sup -1} pc{sup 2}. We combine our sample of dwarf galaxies with a large sample of spiral galaxies from the literature to study scaling relations of L{sub CO} with M{sub B} and metallicity. We find that dwarf galaxies with metallicities of Z Almost-Equal-To 1/2-1/10 Z{sub Sun} have L{sub CO} of 2-4 orders of magnitude smaller than massive spiral galaxies and that their L{sub CO} per unit L{sub B} is 1-2 orders of magnitude smaller. A comparison with tracers of star formation (FUV and 24 {mu}m) shows that L{sub CO} per unit star formation rate (SFR) is 1-2 orders of magnitude smaller in dwarf galaxies. One possible interpretation is that dwarf galaxies form stars much more efficiently: we argue that the low L{sub CO}/SFR ratio is due to the fact that the CO-to-H{sub 2} conversion factor, {alpha}{sub CO}, changes significantly in low-metallicity environments. Assuming that a constant H{sub 2} depletion time of {tau}{sub dep} = 1.8 Gyr holds in dwarf galaxies (as found for a large sample of nearby spirals) implies {alpha}{sub CO} values for dwarf galaxies with Z Almost-Equal-To 1/2-1/10 Z{sub Sun} that are more than one order of magnitude higher than those found in solar metallicity spiral galaxies. Such a significant increase of {alpha}{sub CO} at low metallicity is consistent with previous studies, in particular those of Local Group dwarf galaxies that model dust emission to constrain H{sub 2} masses. Even though it is difficult to parameterize the dependence of {alpha}{sub CO} on metallicity given the currently available data, the results suggest that CO is increasingly difficult to detect at lower metallicities. This has direct consequences for the detectability of star-forming galaxies at high redshift, which presumably have on average sub-solar metallicity.« less

Prognostic Factors for Survival in Patients Treated With Stereotactic Radiosurgery for Recurrent Brain Metastases After Prior Whole Brain Radiotherapy

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

Caballero, Jorge A.; Sneed, Penny K., E-mail: psneed@radonc.ucsf.edu; Lamborn, Kathleen R.

2012-05-01

Purpose: To evaluate prognostic factors for survival after stereotactic radiosurgery (SRS) for new, progressive, or recurrent brain metastases (BM) after prior whole brain radiotherapy (WBRT). Methods and Materials: Patients treated between 1991 and 2007 with Gamma Knife SRS for BM after prior WBRT were retrospectively reviewed. Potential prognostic factors were analyzed overall and by primary site using univariate and stepwise multivariate analyses and recursive partitioning analysis, including age, Karnofsky performance status (KPS), primary tumor control, extracranial metastases, number of BM treated, total SRS target volume, and interval from WBRT to SRS. Results: A total of 310 patients were analyzed, includingmore » 90 breast, 113 non-small-cell lung, 31 small-cell lung, 42 melanoma, and 34 miscellaneous patients. The median age was 56, KPS 80, number of BM treated 3, and interval from WBRT to SRS 8.1 months; 76% had controlled primary tumor and 60% had extracranial metastases. The median survival was 8.4 months overall and 12.0 vs. 7.9 months for single vs. multiple BM treated (p = 0.001). There was no relationship between number of BM and survival after excluding single-BM patients. On multivariate analysis, favorable prognostic factors included age <50, smaller total target volume, and longer interval from WBRT to SRS in breast cancer patients; smaller number of BM, KPS >60, and controlled primary in non-small-cell lung cancer patients; and smaller total target volume in melanoma patients. Conclusions: Among patients treated with salvage SRS for BM after prior WBRT, prognostic factors appeared to vary by primary site. Although survival time was significantly longer for patients with a single BM, the median survival time of 7.9 months for patients with multiple BM seems sufficiently long for salvage SRS to appear to be worthwhile, and no evidence was found to support the use of a cutoff for number of BM appropriate for salvage SRS.« less

Predictable evolution toward flightlessness in volant island birds

PubMed Central

Wright, Natalie A.; Steadman, David W.; Witt, Christopher C.

2016-01-01

Birds are prolific colonists of islands, where they readily evolve distinct forms. Identifying predictable, directional patterns of evolutionary change in island birds, however, has proved challenging. The “island rule” predicts that island species evolve toward intermediate sizes, but its general applicability to birds is questionable. However, convergent evolution has clearly occurred in the island bird lineages that have undergone transitions to secondary flightlessness, a process involving drastic reduction of the flight muscles and enlargement of the hindlimbs. Here, we investigated whether volant island bird populations tend to change shape in a way that converges subtly on the flightless form. We found that island bird species have evolved smaller flight muscles than their continental relatives. Furthermore, in 366 populations of Caribbean and Pacific birds, smaller flight muscles and longer legs evolved in response to increasing insularity and, strikingly, the scarcity of avian and mammalian predators. On smaller islands with fewer predators, birds exhibited shifts in investment from forelimbs to hindlimbs that were qualitatively similar to anatomical rearrangements observed in flightless birds. These findings suggest that island bird populations tend to evolve on a trajectory toward flightlessness, even if most remain volant. This pattern was consistent across nine families and four orders that vary in lifestyle, foraging behavior, flight style, and body size. These predictable shifts in avian morphology may reduce the physical capacity for escape via flight and diminish the potential for small-island taxa to diversify via dispersal. PMID:27071105

Carbon, nitrogen, and phosphorus transport by world rivers

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

Meybeck, M.

1982-04-01

The various forms (dissolved and particulate, organic and inorganic) of carbon, nitrogen, and phosphorus in world rivers are reviewed from literature data. Natural levels are based mainly on major rivers for the subarctic and tropical zones which are still unpolluted and on smaller streams for the temperate zone. Atmospheric fallout is also reviewed. Natural contents of dissolved organic carbon (DOC) are mainly dependent on environmental conditions: DOC varies from 1 mg 1/sup -1/ in the mountainous alpine environments to 20 mg 1/sup -1/ in some taiga rivers. The world DOC average is 5.75 mg l/sup -1/. Nitrogen forms include dissolvedmore » organic nitrogen (DON), dissolved inorganic nitrogen (DIN = N - NH/sub 4//sup +/ + N - NO/sub 3//sup -/ + N - NO/sub 2//sup -/), and particulate organic nitrogen (PON). Natural levels are very low: DIN = 120 ..mu..g 1/sup -1/ of which only 15 percent is present as ammonia, and 1 percent as nitrite. Phosphorus is naturally present in very low amounts: around 10 ..mu..g 1/sup -1/ for P-PO/sub 4//sup 3/ and 25 ..mu..g 1/sup -1/ for total dissolved phosphorus (TDP which includes the organic form). The average nutrient content of rains has been estimated with a set of unpolluted stations: P - PO/sub 4/ = 5 ..mu..g 1/sup -1/, TDP = 10, N - NO/sub 2/ = 5, N - NH/sub 4/ = 225, DON = 225, and N - NO/sub 3/ = 175 ..mu..g 1/sup -1/. TOC levels are probably around several mg 1/sup -1/. These contents are very similar to those found in unpolluted rivers. Man's influence on surface waters has now greatly increased natural nutrient levels. Total dissolved P and N have globally increased by a factor of two and locally (Western Europe, North America) by factors of 10 to 50. These increases were found to be directly proportional to the watershed population and to its energy consumption.« less

Measuring Convective Mass Fluxes Over Tropical Oceans

NASA Astrophysics Data System (ADS)

Raymond, David

2017-04-01

Deep convection forms the upward branches of all large-scale circulations in the tropics. Understanding what controls the form and intensity of vertical convective mass fluxes is thus key to understanding tropical weather and climate. These mass fluxes and the corresponding conditions supporting them have been measured by recent field programs (TPARC/TCS08, PREDICT, HS3) in tropical disturbances considered to be possible tropical storm precursors. In reality, this encompasses most strong convection in the tropics. The measurements were made with arrays of dropsondes deployed from high altitude. In some cases Doppler radar provided additional measurements. The results are in some ways surprising. Three factors were found to control the mass flux profiles, the strength of total surface heat fluxes, the column-integrated relative humidity, and the low to mid-tropospheric moist convective instability. The first two act as expected, with larger heat fluxes and higher humidity producing more precipitation and stronger lower tropospheric mass fluxes. However, unexpectedly, smaller (but still positive) convective instability produces more precipitation as well as more bottom-heavy convective mass flux profiles. Furthermore, the column humidity and the convective instability are anti-correlated, at least in the presence of strong convection. On spatial scales of a few hundred kilometers, the virtual temperature structure appears to be in dynamic balance with the pattern of potential vorticity. Since potential vorticity typically evolves on longer time scales than convection, the potential vorticity pattern plus the surface heat fluxes then become the immediate controlling factors for average convective properties. All measurements so far have taken place in regions with relatively flat sea surface temperature (SST) distributions. We are currently seeking funding for a measurement program in the tropical east Pacific, a region that exhibits strong SST gradients and correspondingly great diversity in the forms of convection. Given the strong boundary layer flows induced by the SST gradients in this region, we hope to determine whether the patterns of convective mass flux seen in other regions persist there.

What physics determines the peak of the IMF? Insights from the structure of cores in radiation-magnetohydrodynamic simulations

DOE PAGES

Krumholz, Mark R.; Myers, Andrew T.; Klein, Richard I.; ...

2016-05-24

As star-forming clouds collapse, the gas within them fragments to ever-smaller masses. Naively one might expect this process to continue down to the smallest mass that is able to radiate away its binding energy on a dynamical time-scale, the opacity limit for fragmentation, at ~0.01M⊙. However, the observed peak of the initial mass function (IMF) lies a factor of 20-30 higher in mass, suggesting that some other mechanism halts fragmentation before the opacity limit is reached. Here, we analyse radiation-magnetohydrodynamic simulations of star cluster formation in typical Milky Way environments in order to determine what physical process limits fragmentation inmore » them. We examine the regions in the vicinity of stars that form in the simulations to determine the amounts of mass that are prevented from fragmenting by thermal and magnetic pressure. We show that, on small scales, thermal pressure enhanced by stellar radiation heating is the dominant mechanism limiting the ability of the gas to further fragment. In the brown dwarf mass regime, ~0.01M⊙, the typical object that forms in the simulations is surrounded by gas whose mass is several times its own that is unable to escape or fragment, and instead is likely to accrete. This mechanism explains why ~0.01M⊙ objects are rare: unless an outside agent intervenes (e.g. a shock strips away the gas around them), they will grow by accreting the warmed gas around them. In contrast, by the time stars grow to masses of ~0.2M⊙, the mass of heated gas is only tens of percent of the central star mass, too small to alter its final mass by a large factor. This naturally explains why the IMF peak is at ~0.2M⊙.« less

Unraveling the electrolyte properties of Na3SbS4 through computation and experiment

NASA Astrophysics Data System (ADS)

Rush, Larry E.; Hood, Zachary D.; Holzwarth, N. A. W.

2017-12-01

Solid-state sodium electrolytes are expected to improve next-generation batteries on the basis of favorable energy density and reduced cost. Na3SbS4 represents a new solid-state ion conductor with high ionic conductivities in the mS/cm range. Here, we explore the tetragonal phase of Na3SbS4 and its interface with metallic sodium anode using a combination of experiments and first-principles calculations. The computed Na-ion vacancy migration energies of 0.1 eV are smaller than the value inferred from experiment, suggesting that grain boundaries or other factors dominate the experimental systems. Analysis of symmetric cells of the electrolyte—Na/Na 3SbS4/Na —show that a conductive solid electrolyte interphase forms. Computer simulations infer that the interface is likely to be related to Na3SbS3 , involving the conversion of the tetrahedral SbS43 - ions of the bulk electrolyte into trigonal pyramidal SbS33 - ions at the interface.

Neutron and weak-charge distributions of the 48Ca nucleus

DOE PAGES

Hagen, Gaute; Forssen, Christian; Nazarewicz, Witold; ...

2015-11-02

What is the size of the atomic nucleus? This deceivably simple question is difficult to answer. Although the electric charge distributions in atomic nuclei were measured accurately already half a century ago, our knowledge of the distribution of neutrons is still deficient. In addition to constraining the size of atomic nuclei, the neutron distribution also impacts the number of nuclei that can exist and the size of neutron stars. We present an ab initio calculation of the neutron distribution of the neutron-rich nucleus 48Ca. We show that the neutron skin (difference between the radii of the neutron and proton distributions)more » is significantly smaller than previously thought. We also make predictions for the electric dipole polarizability and the weak form factor; both quantities that are at present targeted by precision measurements. Here, based on ab initio results for 48Ca, we provide a constraint on the size of a neutron star.« less

Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii

PubMed Central

Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

2016-01-01

Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties. PMID:27467884

Childhood socioeconomic status and childhood maltreatment: Distinct associations with brain structure

PubMed Central

Lawson, Gwendolyn M.; Camins, Joshua S.; Wisse, Laura; Wu, Jue; Duda, Jeffrey T.; Cook, Philip A.; Gee, James C.; Farah, Martha J.

2017-01-01

The present study examined the relationship between childhood socioeconomic status (SES), childhood maltreatment, and the volumes of the hippocampus and amygdala between the ages of 25 and 36 years. Previous work has linked both low SES and maltreatment with reduced hippocampal volume in childhood, an effect attributed to childhood stress. In 46 adult subjects, only childhood maltreatment, and not childhood SES, predicted hippocampal volume in regression analyses, with greater maltreatment associated with lower volume. Neither factor was related to amygdala volume. When current SES and recent interpersonal stressful events were also considered, recent interpersonal stressful events predicted smaller hippocampal volumes over and above childhood maltreatment. Finally, exploratory analyses revealed a significant sex by childhood SES interaction, with women’s childhood SES showing a significantly more positive relation (less negative) with hippocampus volume than men’s. The overall effect of childhood maltreatment but not SES, and the sex-specific effect of childhood SES, indicate that different forms of stressful childhood adversity affect brain development differently. PMID:28414755

Genome sequence of the model mushroom Schizophyllum commune

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

Ohm, Robin A.; de Jong, Jan F.; Lugones, Luis G.

2010-09-01

Much remains to be learned about the biology of mushroom-forming fungi, which are an important source of food, secondary metabolites and industrial enzymes. The wood-degrading fungus Schizophyllum commune is both a genetically tractable model for studying mushroom development and a likely source of enzymes capable of efficient degradation of lignocellulosic biomass. Comparative analyses of its 38.5-megabase genome, which encodes 13,210 predicted genes, reveal the species's unique wood-degrading machinery. One-third of the 471 genes predicted to encode transcription factors are differentially expressed during sexual development of S. commune. Whereas inactivation of one of these, fst4, prevented mushroom formation, inactivation of another,more » fst3, resulted in more, albeit smaller, mushrooms than in the wild-type fungus. Antisense transcripts may also have a role in the formation of fruiting bodies. Better insight into the mechanisms underlying mushroom formation should affect commercial production of mushrooms and their industrial use for producing enzymes and pharmaceuticals.« less

Micromachined silicon parallel acoustic delay lines as time-delayed ultrasound detector array for real-time photoacoustic tomography

NASA Astrophysics Data System (ADS)

Cho, Y.; Chang, C.-C.; Wang, L. V.; Zou, J.

2016-02-01

This paper reports the development of a new 16-channel parallel acoustic delay line (PADL) array for real-time photoacoustic tomography (PAT). The PADLs were directly fabricated from single-crystalline silicon substrates using deep reactive ion etching. Compared with other acoustic delay lines (e.g., optical fibers), the micromachined silicon PADLs offer higher acoustic transmission efficiency, smaller form factor, easier assembly, and mass production capability. To demonstrate its real-time photoacoustic imaging capability, the silicon PADL array was interfaced with one single-element ultrasonic transducer followed by one channel of data acquisition electronics to receive 16 channels of photoacoustic signals simultaneously. A PAT image of an optically-absorbing target embedded in an optically-scattering phantom was reconstructed, which matched well with the actual size of the imaged target. Because the silicon PADL array allows a signal-to-channel reduction ratio of 16:1, it could significantly simplify the design and construction of ultrasonic receivers for real-time PAT.

Torsional deformity of apical vertebra in adolescent idiopathic scoliosis.

PubMed

Kotwicki, Tomasz; Napiontek, Marek

2002-01-01

CT scans of structural thoracic idiopathic scoliosis were reviewed in nine patients admitted to our department for scoliosis surgery. The apical vertebra scans were chosen and the following parameters were evaluated: 1) alpha angle formed by the axis of vertebra and the axis of spinous process 2) beta concave and beta convex angle between the spinous process and the left and right transverse process, respectively, 3) gamma concave and gamma convex angle between the axis of vertebra and the left and right transverse process, respectively, 4) the rotation angle to the sagittal plane. The constant deviation of the spinous process towards the convex side of the curve was observed. The vertebral body itself was distorted towards the concavity of the curve. The angle between the spinous process and the transverse process was smaller on the convex side of the curve. The torsional, intravertebral deformity of the apical vertebra was a factor acting in the direction opposite to the rotation, in the sense to reduce the deformity of the spine in idiopathic scoliosis.

Improvement of Functional Properties of Wheat Gluten Using Acid Protease from Aspergillus usamii.

PubMed

Deng, Lingli; Wang, Zhaoxia; Yang, Sheng; Song, Junmei; Que, Fei; Zhang, Hui; Feng, Fengqin

2016-01-01

Hydrolysis parameters (temperature, E/S ratio, pH, and time) for acid protease (from Aspergillus usamii) hydrolysis of wheat gluten were optimized by response surface methodology (RSM) using emulsifying activity index (EAI) as the response factor. A temperature of 48.9°C, E/S ratio of 1.60%, pH 3.0, hydrolysis time of 2.5 h was found to be the optimum condition to obtain wheat gluten hydrolysate with higher EAI. The solubility of wheat gluten was greatly improved by hydrolysis and became independent of pH over the studied range. Enzymatic hydrolysis resulted in dramatically increase in EAI, water and oil holding capacity. Molecular weight distribution results showed that most of the peptides above 10 kDa have been hydrolyzed into smaller peptides. The results of FTIR spectra and disulfide bond (SS) and sulfhydryl (SH) content suggested that a more extensional conformation was formed after hydrolysis, which could account for the improved functional properties.

Development of a high-definition IR LED scene projector

NASA Astrophysics Data System (ADS)

Norton, Dennis T.; LaVeigne, Joe; Franks, Greg; McHugh, Steve; Vengel, Tony; Oleson, Jim; MacDougal, Michael; Westerfeld, David

2016-05-01

Next-generation Infrared Focal Plane Arrays (IRFPAs) are demonstrating ever increasing frame rates, dynamic range, and format size, while moving to smaller pitch arrays.1 These improvements in IRFPA performance and array format have challenged the IRFPA test community to accurately and reliably test them in a Hardware-In-the-Loop environment utilizing Infrared Scene Projector (IRSP) systems. The rapidly-evolving IR seeker and sensor technology has, in some cases, surpassed the capabilities of existing IRSP technology. To meet the demands of future IRFPA testing, Santa Barbara Infrared Inc. is developing an Infrared Light Emitting Diode IRSP system. Design goals of the system include a peak radiance >2.0W/cm2/sr within the 3.0-5.0μm waveband, maximum frame rates >240Hz, and >4million pixels within a form factor supported by pixel pitches <=32μm. This paper provides an overview of our current phase of development, system design considerations, and future development work.

Subjective Sleep Quality as a Possible Mediator in the Relationship between Personality Traits and Depressive Symptoms in Middle-Aged Adults

PubMed Central

Peck, Katlyn; Mallya, Sasha; Lupien, Sonia J.

2016-01-01

This study explored the mediating role of sleep in the relationship between personality traits and depressive symptoms in a group of community-dwelling men and women (Mage = 57.92, SD = 4.00). Participants completed the short form NEO Five Factor Inventory (NEO-FFI), Pittsburgh Sleep Quality Index (PSQI), and the Center for Epidemiologic Studies Depression Scale (CES-D). High neuroticism and low conscientiousness was associated with poor sleep, as well as greater depressive symptom severity. Partial indirect mediation effects were found between personality traits (i.e., neuroticism and conscientiousness) and depressive symptoms through self-report sleep measures. An alternative model was also explored, entering depression as the mediator; however a smaller portion of the variance was explained by this model, compared with the hypothesized model. The current study provides preliminary information regarding the mechanisms that influence the relationship between personality traits, sleep, and depression among a group of community-dwelling middle-aged adults. Implications and future directions are discussed. PMID:27285159

Effects of nonmagnetic disorder on the energy of Yu-Shiba-Rusinov states

NASA Astrophysics Data System (ADS)

Kiendl, Thomas; von Oppen, Felix; Brouwer, Piet W.

2017-10-01

We study the sensitivity of Yu-Shiba-Rusinov states, bound states that form around magnetic scatterers in superconductors, to the presence of nonmagnetic disorder in both two and three dimensional systems. We formulate a scattering approach to this problem and reduce the effects of disorder to two contributions: disorder-induced normal reflection and a random phase of the amplitude for Andreev reflection. We find that both of these are small even for moderate amounts of disorder. In the dirty limit in which the disorder-induced mean free path is smaller than the superconducting coherence length, the variance of the energy of the Yu-Shiba-Rusinov state remains small in the ratio of the Fermi wavelength and the mean free path. This effect is more pronounced in three dimensions, where only impurities within a few Fermi wavelengths of the magnetic scatterer contribute. In two dimensions the energy variance is larger by a logarithmic factor because impurities contribute up to a distance of the order of the superconducting coherence length.

Artificial reproduction of two different spawn-forms of the chub.

PubMed

Krejszeff, Sławomir; Targońska, Katarzyna; Zarski, Daniel; Kucharczyk, Dariusz

2010-03-01

The aim of this study was to compare, under controlled conditions, reproduction results of cultured and wild stock of the chub. Wild fish spawned only once a season whereas the cultured stock spawned at least two times. In the multiple-spawn stock, fewer fish spawned and the weight of produced oocytes was reduced compared to the single-spawn stock. Larvae obtained from the multi-spawn forms were smaller than those of the single-spawn stock. The occurrence of one species with two forms of spawning performance in the same area makes it difficult to develop an efficient method for controlling the reproduction.

Influence of Pre-Existing Structure on Sill Geometry in the San Rafael Volcanic Field, Central Utah

NASA Astrophysics Data System (ADS)

Ferwerda, B.; Wetmore, P. H.; Connor, C.; Kruse, S. E.; Kiyosugi, K.; Kiflu, H. G.

2011-12-01

Sills have been hypothesized to be formed at rigidity contrasts between layers or at the level of neutral buoyancy of the intruding magma body. Recent field observations of sills in the San Rafael Volcanic Field (SRVF) in central Utah conflict with both of these hypotheses, suggesting that something else may control the distribution of sills in the crust. This study examines the role pre-existing structure plays in determining the distribution and geometry of sills in the SRVF. Primarily, sills will be thickest in the hinge zone of synclines and thinnest towards the limbs. The SRVF consists of a series of dikes, conduits and sills intruded into the J-Kr strata of the western Colorado Plateau. The structure of the SRVF consists of a series of broad wavelength folds truncated by a major thrust fault as determined by a gravity profile across structure. There are several sill complexes in the area whose geometry and relationships with the host rock are unaccounted for by these hypotheses. At large scale, sills follow structural trends in the host rock. Sills are either oriented with regional dips, or follow the trends of folds in the area. One sill, in particular, intruded into a syncline and thins towards the limb of the fold. However, sills behave differently at smaller spatial scales. The smaller scale behavior is incongruent with sills forming at rigidity contrasts or at the level of neutral buoyancy. First, sills form tiered structures intruding at multiple stratigraphic levels within the field area, and in limited geographic extent. Geophysical surveys confirm tiered sill structures in the subsurface. Individual sills also change stratigraphic levels, sometimes, very abruptly, moving vertically up to 30 meters in short horizontal distances. Sills also form networks in anastomosing structures that cut across stratigraphy at varying angles. These observations suggest that neither the level of neutral buoyancy nor the rigidity contrasts between layers play a role in determining the distribution of sills in the crust. Broadly, sills follow pre-existing structure, but at smaller scales, sills behave drastically different, with little regard to bedding planes.

The influence of a prediction display on the quasi-linear describing function and remnant measured with an adaptive analog-pilot in a closed loop

NASA Technical Reports Server (NTRS)

Dey, D.

1972-01-01

The effect of a prediction display on the human transfer characteristics is explained with the aid of a quasi-linear model. The prediction display causes an increase of the gain factor and the lead factor, a diminishing of the lag factor and a decrease of the remnant. Altogether, these factors yield a smaller mean square value of the control deviation and a simultaneous decrease of the mean square value of the stick signal.

Zinc Alloys for the Fabrication of Semiconductor Devices

NASA Technical Reports Server (NTRS)

Ryu, Yungryel; Lee, Tae S.

2009-01-01

ZnBeO and ZnCdSeO alloys have been disclosed as materials for the improvement in performance, function, and capability of semiconductor devices. The alloys can be used alone or in combination to form active photonic layers that can emit over a range of wavelength values. Materials with both larger and smaller band gaps would allow for the fabrication of semiconductor heterostructures that have increased function in the ultraviolet (UV) region of the spectrum. ZnO is a wide band-gap material possessing good radiation-resistance properties. It is desirable to modify the energy band gap of ZnO to smaller values than that for ZnO and to larger values than that for ZnO for use in semiconductor devices. A material with band gap energy larger than that of ZnO would allow for the emission at shorter wavelengths for LED (light emitting diode) and LD (laser diode) devices, while a material with band gap energy smaller than that of ZnO would allow for emission at longer wavelengths for LED and LD devices. The amount of Be in the ZnBeO alloy system can be varied to increase the energy bandgap of ZnO to values larger than that of ZnO. The amount of Cd and Se in the ZnCdSeO alloy system can be varied to decrease the energy band gap of ZnO to values smaller than that of ZnO. Each alloy formed can be undoped or can be p-type doped using selected dopant elements, or can be n-type doped using selected dopant elements. The layers and structures formed with both the ZnBeO and ZnCdSeO semiconductor alloys - including undoped, p-type-doped, and n-type-doped types - can be used for fabricating photonic and electronic semiconductor devices for use in photonic and electronic applications. These devices can be used in LEDs, LDs, FETs (field effect transistors), PN junctions, PIN junctions, Schottky barrier diodes, UV detectors and transmitters, and transistors and transparent transistors. They also can be used in applications for lightemitting display, backlighting for displays, UV and visible transmitters and detectors, high-frequency radar, biomedical imaging, chemical compound identification, molecular identification and structure, gas sensors, imaging systems, and for the fundamental studies of atoms, molecules, gases, vapors, and solids.

Are LIGO's Black Holes Made From Smaller Black Holes?

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-05-01

The recent successes of the Laser Interferometer Gravitational-Wave Observatory (LIGO) has raised hopes that several long-standing questions in black-hole physics will soon be answerable. Besides revealing how the black-hole binary pairs are built, could detections with LIGO also reveal how the black holes themselves form?Isolation or HierarchyThe first detection of gravitational waves, GW150914, was surprising for a number of reasons. One unexpected result was the mass of the two black holes that LIGO saw merging: they were a whopping 29 and 36 solar masses.On the left of this schematic, two first-generation (direct-collapse) black holes form a merging binary. The right illustrates a second-generation hierarchical merger: each black hole in the final merging binary was formed by the merger of two smaller black holes. [Adapted fromGerosa et al., a simultaneously published paper that also explores the problem of hierarchical mergers and reaches similar conclusions]How do black holes of this size form? One possibility is that they form in isolation from the collapse of a single massive star. In an alternative model, they are created through the hierarchical merger of smaller black holes, gradually building up to the size we observed.A team of scientists led by Maya Fishbach (University of Chicago) suggests that we may soon be able to tell whether or not black holes observed by LIGO formed hierarchically. Fishbach and collaborators argue that hierarchical formation leaves a distinctive signature on the spins of the final black holes and that as soon as we have enough merger detections from LIGO, we can use spin measurements to statistically determine if LIGO black holes were formed hierarchically.Spins from Major MergersWhen two black holes merge, both their original spins and the angular momentum of the pair contribute to the spin of the final black hole that results. Fishbach and collaborators calculate the expected distribution of these final spins assuming that all the hierarchical mergers are so-called major mergers i.e., the smaller black hole of the pair is at least 70% of the mass of the larger one.Distribution of spins for 4th-generation mergers, with two different mass ratios (q= 0.7 and q= 1) and initial first-generation spins (non-spinning and maximally spinning). [Fishbach et al. 2017]The authors find that hierarchical major mergers result in a distribution of spins with a distinctive shape, peaking at a spin of a 0.7 with relatively low contribution from spins below a 0.5. Intriguingly, this distribution is universal if you include several generations of mergers, the resulting spin distribution converges to the same shape every time. This is true regardless of the details of the hierarchical merger scenario, like the exact black hole mass ratio (as long as only major mergers occur) or the initial spin distributions.Testing the ModelWhat does this tell us? Since the hierarchical merger model predicts a very specific distribution of spins for the black holes detected by LIGO, we can compare future LIGO detections to see if theyre consistent with this model.The authors calculate the statistics to show that after order 100 LIGO detections, we should be able to tell whether these black holes are consistent with a hierarchical merger formation model or not. With luck, this could mean that we will have solved this mystery within a few years of advanced LIGO operations!CitationMaya Fishbach et al 2017 ApJL 840 L24. doi:10.3847/2041-8213/aa7045

Confirmatory Factor Analysis Alternative: Free, Accessible CBID Software.

PubMed

Bott, Marjorie; Karanevich, Alex G; Garrard, Lili; Price, Larry R; Mudaranthakam, Dinesh Pal; Gajewski, Byron

2018-02-01

New software that performs Classical and Bayesian Instrument Development (CBID) is reported that seamlessly integrates expert (content validity) and participant data (construct validity) to produce entire reliability estimates with smaller sample requirements. The free CBID software can be accessed through a website and used by clinical investigators in new instrument development. Demonstrations are presented of the three approaches using the CBID software: (a) traditional confirmatory factor analysis (CFA), (b) Bayesian CFA using flat uninformative prior, and (c) Bayesian CFA using content expert data (informative prior). Outcomes of usability testing demonstrate the need to make the user-friendly, free CBID software available to interdisciplinary researchers. CBID has the potential to be a new and expeditious method for instrument development, adding to our current measurement toolbox. This allows for the development of new instruments for measuring determinants of health in smaller diverse populations or populations of rare diseases.

Inversion for the driving forces of plate tectonics

NASA Technical Reports Server (NTRS)

Richardson, R. M.

1983-01-01

Inverse modeling techniques have been applied to the problem of determining the roles of various forces that may drive and resist plate tectonic motions. Separate linear inverse problems have been solved to find the best fitting pole of rotation for finite element grid point velocities and to find the best combination of force models to fit the observed relative plate velocities for the earth's twelve major plates using the generalized inverse operator. Variance-covariance data on plate motion have also been included. Results emphasize the relative importance of ridge push forces in the driving mechanism. Convergent margin forces are smaller by at least a factor of two, and perhaps by as much as a factor of twenty. Slab pull, apparently, is poorly transmitted to the surface plate as a driving force. Drag forces at the base of the plate are smaller than ridge push forces, although the sign of the force remains in question.

Petasiger islandicus n. sp. (Digenea: Echinostomatidae) in the horned grebe Podiceps auritus (L.) (Aves: Podicipedidae) from Iceland.

PubMed

Kostadinova, Aneta; Skirnisson, Karl

2007-11-01

Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Mývatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly.

Partner age differences and associated sexual risk behaviours among adolescent girls and young women in a cash transfer programme for schooling in Malawi.

PubMed

Beauclair, Roxanne; Dushoff, Jonathan; Delva, Wim

2018-03-27

Age disparities in sexual relationships have been proposed as a key risk factor for HIV transmission in Sub-Saharan Africa, but evidence remains inconclusive. The SIHR study, a cluster randomised trial of a cash transfer programme in Malawi, found that young women in the intervention groups were less likely to have had a sexual partner aged 25 or older, and less likely to test positive for HIV and HSV-2 at follow-up compared to control groups. We examined the hypotheses that girls in the intervention groups had smaller age differences than control groups and that large age differences were associated with relationship-level HIV transmission risk factors: inconsistent condom use, sex frequency, and relationship duration. We conducted an analysis of schoolgirls in the Schooling, Income, and Health Risk (SIHR) study aged 13-22 at baseline (n = 2907). We investigated the effects of study arm, trial stage and participant age on age differences in sexual relationships using a linear mixed-effects model. Cumulative-link mixed-effects models were used to estimate the effect of relationship age difference on condom use and sex frequency, and a Cox proportional hazard model was used to estimate the effect of relationship age difference on relationship duration. We controlled for the girl's age, number of partners, study group and study round. Girls receiving cash transfers, on average, had smaller age differences in relationships compared to controls, though the estimated difference was not statistically significant (- 0.43 years; 95% CI: -1.03, 0.17). The older the participant was, the smaller her age differences (- 0.67 per 4-year increase in age; 95% CI: -0.99, - 0.35). Among controls, after the cash transfers had ended the average age difference was 0.82 years larger than during the intervention (95% CI: 0.43, 1.21), suggesting a possible indirect effect of the study on behaviour in the community as a whole. Across treatment groups, larger age differences in relationships were associated with lower levels of condom use, more frequent sex, and longer relationship durations. Cash-transfer programmes may prevent HIV transmission in part by encouraging young women to form age-similar relationships, which are characterised by increased condom use and reduced sex frequency. The benefits of these programmes may extend to those who are not directly receiving the cash.

Historical and Cultural Perspectives on Centralization/Decentralization in Continuing Education.

ERIC Educational Resources Information Center

Edelson, Paul J.

1995-01-01

Views centralization/decentralization from four perspectives: historical, as an outgrowth of professionalism, in the culture of higher education, and management theory. Suggests that some form of centralized control will always be necessary if continuing education is to function in a larger organization, but smaller units may be the wave of the…

A novel emulsion-forming arabinogalactan gum from the stems of Frost grape (Vitis riparia Michx.)

USDA-ARS?s Scientific Manuscript database

A novel arabinogalactan polysaccharide (FGP) is described that is produced in large quantities from the cut stems of Frost grape (Vitis riparia Michx.). The sugar composition consists of L-arabinofuranose (L-Araf, 55.2 %) and D-galactopyranose (D-Galp 30.1%), with smaller components of D-xylose (11....

78 FR 63139 - Designee for Patient Personal Property

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-23

... Benefits. However, VA Form 10-10EZ does not include a space for a veteran to designate someone to receive... information on several key elements of the designation process. We propose to divide it into several smaller... that are derived from gratuitous benefits under laws administered by VA. It further states that the...

17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

Code of Federal Regulations, 2010 CFR

2010-04-01

... EXCHANGE COMMISSION FORM AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF 1933..., INVESTMENT ADVISERS ACT OF 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Article 8 Financial Statements of Smaller Reporting Companies § 210.8-06 Real estate operations acquired or to be acquired. If...

Analysis of County School Districts in Arkansas.

ERIC Educational Resources Information Center

Budd, Karol B.; Charlton, J.L.

The 1948, Arkansas School District Reorganization Act was passed in an effort to reduce the 1589 small school districts to a smaller number. Those districts not consolidated would form county districts. As of the 1967-68 school year, 26 of these county districts remained. The purpose of this study was to provide information drawing attention to…

17 CFR 210.8-08 - Age of financial statements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 17 Commodity and Securities Exchanges 2 2013-04-01 2013-04-01 false Age of financial statements. 210.8-08 Section 210.8-08 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION FORM... CONSERVATION ACT OF 1975 Article 8 Financial Statements of Smaller Reporting Companies § 210.8-08 Age of...

17 CFR 210.8-08 - Age of financial statements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 17 Commodity and Securities Exchanges 2 2012-04-01 2012-04-01 false Age of financial statements. 210.8-08 Section 210.8-08 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION FORM... CONSERVATION ACT OF 1975 Article 8 Financial Statements of Smaller Reporting Companies § 210.8-08 Age of...

17 CFR 210.8-08 - Age of financial statements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 17 Commodity and Securities Exchanges 3 2014-04-01 2014-04-01 false Age of financial statements. 210.8-08 Section 210.8-08 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION FORM... CONSERVATION ACT OF 1975 Article 8 Financial Statements of Smaller Reporting Companies § 210.8-08 Age of...

The Organization of Children's Same-Sex Peer Relationships.

ERIC Educational Resources Information Center

Benenson, Joyce; Apostoleris, Nicholas; Parnass, Jodi

1998-01-01

Uses a sociometric analysis to explore the differential organization of boys' and girls' peer groups. Finds that boys structure their peer groups by creating a large central cluster composed of smaller integrated clusters, whereas girls form small clusters unrelated to one another. Nevertheless, girls are aware of and sensitive to the status of…

One-dimensional Confinement Effect on the Self-assembly of Symmetric H-shaped Copolymers in a Thin Film.

PubMed

Mu, Dan; Li, Jian-Quan; Feng, Sheng-Yu

2017-10-19

The self-assembly of a reformed symmetric H-shaped copolymer with four hydrophilic branches and one hydrophobic stem was systematically investigated. The existence of vacancies is vital to regulate the sizes of self-assembled cylinders to be able to form a hexagonal arrangement. With the introduction of horizontal-orientated confinement, a micellar structure is formed through a coalescence mechanism. The short acting distance and large influencing area of the confinement produces numerous small-sized micelles. Additionally, the cycled "contraction-expansion" change helps achieve hexagonal arrangement. In contrast, the introduction of lateral-oriented confinement with long acting distance and small influencing area cannot change the cylindrical structure. Under the fission mechanism, in which the larger cylinder splits into smaller ones, it is quite efficient to generate hierarchical-sized cylinders from larger-sized cylinders in the middle region and smaller-sized cylinders near both walls. The results indicate the possibility of regulating the characteristics of a nanomaterial by tuning the molecular structure of the copolymer and the parameters of the introduced confinement, which are closely related to the self-assembly structure.

Structure of interphase chromosomes in the nuclei of Drosophila cells.

PubMed

Banfalvi, Gaspar

2006-10-01

Fluorescent images of interphase chromatin structures and chromosome structures isolated from reversibly permeable Drosophila cells were analyzed. Decondensed chromatin in early S phase (2.0-2.5 C-value) consisted of a veil-like fibrillary network. Fibrillar chromatin formed rodlets later in the early S phase (2.5-2.75 C). Drosophila chromosomes contain several smaller subunits called rodlets. Fibrillar chromatin turned to chromatin ribbon and the early mid-S-phase globular chromosomes (2.75-3.0 C), then to opened fibrous globular forms later in the mid-S-phase (3.0-3.25 C), to late-S-phase supercoiled ribbons (3.25-3.5 C), end-S-phase elongated prechromosomes (3.5-3.75 C), bent and linear chromosomes (3.75-4.0 C). Early-S phase chromatin fibrils in the nuclei of Drosophila cells are thinner than the veil-like structures in mammalian cells. The connectivity of chromosomes shows linear arrangement (3, 1, 2, 4), with larger chromosomes (1 and 2) inside and smaller chromosomes (3, 4) at the two ends in the chromosomal chain.

Ab-Initio Calculation of Electronic Structure of Lead Halide Perovskites with Formamidinium Cation as an Active Material for Perovskite Solar Cells

NASA Astrophysics Data System (ADS)

Indari, E. D.; Wungu, T. D. K.; Hidayat, R.

2017-07-01

Organic lead halide perovskite material based solar cells show impressive power conversion efficiencies, which can reach above 19 percent for perovskite solar cell with methyl-ammonium cations. These efficiencies are originated from efficient photoexcitation and charge carrier transport and not observed in conventional perovskite crystals. In this preliminary research work, we therefore performed Density Functional Theory (DFT) calculation of formamidinium lead iodide (FAPI), an alternative to methyl-ammonium lead iodide (MAPI), to predict their electronic structure and density of state (DOS). The calculation result at the most stable lattice parameters show a good agreement with the experiment results. The obtained band gap energy is 1.307 eV. The valence band is dominantly formed by the 5p orbitals of I- anions, while the conduction band is dominantly formed by the 6p orbitals of Pb2+ cations. The DOS of valence band of this perovskite seems smaller compared to the case of methyl-ammonium lead iodide perovskite, which then may explain the observation of smaller power conversion efficiencies in perovskite solar cells with this formamidinium cations.

Turbulent stresses and secondary currents in a tidal-forced channel with significant curvature and asymmetric bed forms

USGS Publications Warehouse

Fong, D.A.; Monismith, Stephen G.; Stacey, M.T.; Burau, J.R.

2009-01-01

Acoustic Doppler current profilers are deployed to measure both the mean flow and turbulent properties in a channel with significant curvature. Direct measurements of the Reynolds stress show a significant asymmetry over the tidal cycle where stresses are enhanced during the flood tide and less prominent over the ebb tide. This asymmetry is corroborated by logarithmic fits using 10 min averaged velocity data. A smaller yet similar tendency asymmetry in drag coefficient is inferred by fitting the velocity and estimated large-scale pressure gradient to a one-dimensional along-channel momentum balance. This smaller asymmetry is consistent with recent modeling work simulating regional flows in the vicinity of the study site. The asymmetry in drag suggests the importance of previously reported bed forms for this channel and demonstrates spatial and temporarily variations in bed stress. Secondary circulation patterns observed in a relatively straight section of channel appear driven by local curvature rather than being remotely forced by the regions of significant curvature only a few hundred meters from the measurement site. ?? 2009 ASCE.

The Nrf1 CNC-bZIP protein is regulated by the proteasome and activated by hypoxia.

PubMed

Chepelev, Nikolai L; Bennitz, Joshua D; Huang, Ting; McBride, Skye; Willmore, William G

2011-01-01

Nrf1 (nuclear factor-erythroid 2 p45 subunit-related factor 1) is a transcription factor mediating cellular responses to xenobiotic and pro-oxidant stress. Nrf1 regulates the transcription of many stress-related genes through the electrophile response elements (EpREs) located in their promoter regions. Despite its potential importance in human health, the mechanisms controlling Nrf1 have not been addressed fully. We found that proteasomal inhibitors MG-132 and clasto-lactacystin-β-lactone stabilized the protein expression of full-length Nrf1 in both COS7 and WFF2002 cells. Concomitantly, proteasomal inhibition decreased the expression of a smaller, N-terminal Nrf1 fragment, with an approximate molecular weight of 23 kDa. The EpRE-luciferase reporter assays revealed that proteasomal inhibition markedly inhibited the Nrf1 transactivational activity. These results support earlier hypotheses that the 26 S proteasome processes Nrf1 into its active form by removing its inhibitory N-terminal domain anchoring Nrf1 to the endoplasmic reticulum. Immunoprecipitation demonstrated that Nrf1 is ubiquitinated and that proteasomal inhibition increased the degree of Nrf1 ubiquitination. Furthermore, Nrf1 protein had a half-life of approximately 5 hours in COS7 cells. In contrast, hypoxia (1% O(2)) significantly increased the luciferase reporter activity of exogenous Nrf1 protein, while decreasing the protein expression of p65, a shorter form of Nrf1, known to act as a repressor of EpRE-controlled gene expression. Finally, the protein phosphatase inhibitor okadaic acid activated Nrf1 reporter activity, while the latter was repressed by the PKC inhibitor staurosporine. Collectively, our data suggests that Nrf1 is controlled by several post-translational mechanisms, including ubiquitination, proteolytic processing and proteasomal-mediated degradation as well as by its phosphorylation status. © 2011 Chepelev et al.

C III] Emission in Star-forming Galaxies at z ∼ 1

NASA Astrophysics Data System (ADS)

Du, Xinnan; Shapley, Alice E.; Martin, Crystal L.; Coil, Alison L.

2017-03-01

The C III]λλ1907, 1909 rest-frame UV emission doublet has recently been detected in galaxies during the epoch of reionization (z > 6), with a high equivalent width (EW; 10 Å, rest frame). Currently, it is possible to obtain much more detailed information for star-forming galaxies at significantly lower redshift. Accordingly, studies of their far-UV spectra are useful for understanding the factors modulating the strength of C III] emission. We present the first statistical sample of C III] emission measurements in star-forming galaxies at z ∼ 1. Our sample is drawn from the DEEP2 survey and spans the redshifts 0.64 ≤slant z ≤slant 1.35 (< z> =1.08). We find that the median EW of individual C III] detections in our sample (1.30 Å) is much smaller than the typical value observed thus far at z > 6. Furthermore, out of 184 galaxies with coverage of C III], only 40 have significant detections. Galaxies with individual C III] detections have bluer colors and lower luminosities on average than those without, implying that strong C III] emitters are in general young and low-mass galaxies without significant dust extinction. Using stacked spectra, we further investigate how C III] strength correlates with multiple galaxy properties (M B , U ‑ B, M *, star formation rate, specific star formation rate) and rest-frame near-UV (Fe II* and Mg II) and optical ([O III] and Hβ) emission line strengths. These results provide a detailed picture of the physical environment in star-forming galaxies at z ∼ 1, and motivate future observations of strong C III] emitters at similar redshifts.

Astrocyte-Secreted Factors Selectively Alter Neural Stem and Progenitor Cell Proliferation in the Fragile X Mouse

PubMed Central

Sourial, Mary; Doering, Laurie C.

2016-01-01

An increasing body of evidence indicates that astrocytes contribute to the governance and fine tuning of stem and progenitor cell production during brain development. The effect of astrocyte function in cell production in neurodevelopmental disorders is unknown. We used the Neural Colony Forming Cell assay to determine the effect of astrocyte conditioned media (ACM) on the generation of neurospheres originating from either progenitor cells or functional stem cells in the knock out (KO) Fragile X mouse model. ACM from both normal and Fmr1-KO mice generated higher percentages of smaller neurospheres indicative of restricted proliferation of the progenitor cell population in Fmr1-KO brains. Wild type (WT) neurospheres, but not KO neurospheres, showed enhanced responses to ACM from the Fmr1-KO mice. In particular, Fmr1-KO ACM increased the percentage of large neurospheres generated, representative of spheres produced from neural stem cells. We also used 2D DIGE to initiate identification of the astrocyte-secreted proteins with differential expression between Fmr1-KO and WT cortices and hippocampi. The results further support the critical role of astrocytes in governing neural cell production in brain development and point to significant alterations in neural cell proliferation due to astrocyte secreted factors from the Fragile X brain. Highlights: • We studied the proliferation of neural stem and progenitor cells in Fragile X. • We examined the role of astrocyte-secreted factors in neural precursor cell biology. • Astrocyte-secreted factors with differential expression in Fragile X identified. PMID:27242437

Self-esteem levels and cardiovascular and inflammatory responses to acute stress.

PubMed

O'Donnell, Katie; Brydon, Lena; Wright, Caroline E; Steptoe, Andrew

2008-11-01

Acute mental stress tests have helped to clarify the pathways through which psychosocial factors are linked to disease risk. This methodology is now being used to investigate potentially protective psychosocial factors. We investigated whether global self-esteem might buffer cardiovascular and inflammatory responses to acute stress. One hundred and one students completed the Rosenberg Self-Esteem Scale. Heart rate and heart rate variability (HRV) were recorded for 5 min periods at baseline, during two mental stress tasks, (a speech and a color-word task) and 10, 25 and 40 min into a recovery period. Plasma levels of tumor-necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL-1Ra) were assessed at baseline, immediately post-stress and after 45 min recovery. Repeated measures analysis of variance demonstrated that heart rate levels were lower across all time points in those with high self-esteem, although heart rate reactivity to stress was not related to self-esteem. There were no differences in baseline HRV, TNF-alpha, IL-6 or IL-1Ra. Multiple linear regressions revealed that greater self-esteem was associated with a smaller reduction in heart rate variability during the speech task, but not the color-word task. Greater self-esteem was associated with smaller TNF-alpha and IL-1Ra responses immediately following acute stress and smaller IL-1Ra responses at 45 min post-stress. In conclusion, global self-esteem is associated with lower heart rate and attenuated HRV and inflammatory responses to acute stress. These responses could be processes through which self-esteem protects against the development of disease.

Analysis of influential factors for the relationship between PM2.5 and AOD in Beijing

NASA Astrophysics Data System (ADS)

Zheng, Caiwang; Zhao, Chuanfeng; Zhu, Yannian; Wang, Yang; Shi, Xiaoqin; Wu, Xiaolin; Chen, Tianmeng; Wu, Fang; Qiu, Yanmei

2017-11-01

The relationship between aerosol optical depth (AOD) and PM2.5 is often investigated in order to obtain surface PM2.5 from satellite observation of AOD with a broad area coverage. However, various factors could affect the AOD-PM2.5 regressions. Using both ground and satellite observations in Beijing from 2011 to 2015, this study analyzes the influential factors including the aerosol type, relative humidity (RH), planetary boundary layer height (PBLH), wind speed and direction, and the vertical structure of aerosol distribution. The ratio of PM2.5 to AOD, which is defined as η, and the square of their correlation coefficient (R2) have been examined. It shows that η varies from 54.32 to 183.14, 87.32 to 104.79, 95.13 to 163.52, and 1.23 to 235.08 µg m-3 with aerosol type in spring, summer, fall, and winter, respectively. η is smaller for scattering-dominant aerosols than for absorbing-dominant aerosols, and smaller for coarse-mode aerosols than for fine-mode aerosols. Both RH and PBLH affect the η value significantly. The higher the RH, the smaller the η, and the higher the PBLH, the smaller the η. For AOD and PM2.5 data with the correction of RH and PBLH compared to those without, R2 of monthly averaged PM2.5 and AOD at 14:00 LT increases from 0.63 to 0.76, and R2 of multi-year averaged PM2.5 and AOD by time of day increases from 0.01 to 0.93, 0.24 to 0.84, 0.85 to 0.91, and 0.84 to 0.93 in four seasons respectively. Wind direction is a key factor for the transport and spatial-temporal distribution of aerosols originated from different sources with distinctive physicochemical characteristics. Similar to the variation in AOD and PM2.5, η also decreases with the increasing surface wind speed, indicating that the contribution of surface PM2.5 concentrations to AOD decreases with surface wind speed. The vertical structure of aerosol exhibits a remarkable change with seasons, with most particles concentrated within about 500 m in summer and within 150 m in winter. Compared to the AOD of the whole atmosphere, AOD below 500 m has a better correlation with PM2.5, for which R2 is 0.77. This study suggests that all the above influential factors should be considered when we investigate the AOD-PM2.5 relationships.

A Model for Protostellar Cluster Luminosities and the Impact on the CO–H2 Conversion Factor

NASA Astrophysics Data System (ADS)

Gaches, Brandt A. L.; Offner, Stella S. R.

2018-02-01

We construct a semianalytic model to study the effect of far-ultraviolet (FUV) radiation on gas chemistry from embedded protostars. We use the protostellar luminosity function (PLF) formalism of Offner & McKee to calculate the total, FUV, and ionizing cluster luminosity for various protostellar accretion histories and cluster sizes. We2 compare the model predictions with surveys of Gould Belt star-forming regions and find that the tapered turbulent core model matches best the mean luminosities and the spread in the data. We combine the cluster model with the photodissociation region astrochemistry code, 3D-PDR, to compute the impact of the FUV luminosity from embedded protostars on the CO-to-H2 conversion factor, X CO, as a function of cluster size, gas mass, and star formation efficiency. We find that X CO has a weak dependence on the FUV radiation from embedded sources for large clusters owing to high cloud optical depths. In smaller and more efficient clusters the embedded FUV increases X CO to levels consistent with the average Milky Way values. The internal physical and chemical structures of the cloud are significantly altered, and X CO depends strongly on the protostellar cluster mass for small efficient clouds.

Preconditioning 2D Integer Data for Fast Convex Hull Computations

PubMed Central

2016-01-01

In order to accelerate computing the convex hull on a set of n points, a heuristic procedure is often applied to reduce the number of points to a set of s points, s ≤ n, which also contains the same hull. We present an algorithm to precondition 2D data with integer coordinates bounded by a box of size p × q before building a 2D convex hull, with three distinct advantages. First, we prove that under the condition min(p, q) ≤ n the algorithm executes in time within O(n); second, no explicit sorting of data is required; and third, the reduced set of s points forms a simple polygonal chain and thus can be directly pipelined into an O(n) time convex hull algorithm. This paper empirically evaluates and quantifies the speed up gained by preconditioning a set of points by a method based on the proposed algorithm before using common convex hull algorithms to build the final hull. A speedup factor of at least four is consistently found from experiments on various datasets when the condition min(p, q) ≤ n holds; the smaller the ratio min(p, q)/n is in the dataset, the greater the speedup factor achieved. PMID:26938221

Vascular plant species richness along environmental gradients in a cool temperate to sub-alpine mountainous zone in central Japan.

PubMed

Tsujino, Riyou; Yumoto, Takakazu

2013-03-01

In order to clarify how vegetation types change along the environmental gradients in a cool temperate to sub-alpine mountainous zone and the determinant factors that define plant species richness, we established 360 plots (each 4 × 10 m) within which the vegetation type, species richness, elevation, topographic position index (TPI), slope inclination, and ground light index (GLI) of the natural vegetation were surveyed. Mean elevation, TPI, slope inclination, and GLI differed across vegetation types. Tree species richness was negatively correlated with elevation, whereas fern and herb species richness were positively correlated. Tree species richness was greater in the upper slope area than the lower slope area, whereas fern and herb species richness were greater in the lower slope area. Ferns and trees species richness were smaller in the open canopy, whereas herb species richness was greater in the open canopy. Vegetation types were determined firstly by elevation and secondary by topographic configurations, such as topographic position, and slope inclination. Elevation and topography were the most important factors affecting plant richness, but the most influential variables differed among plant life-form groups. Moreover, the species richness responses to these environmental gradients greatly differed among ferns, herbs, and trees.

Relationships among Egg Size, Composition, and Energy: A Comparative Study of Geminate Sea Urchins

PubMed Central

McAlister, Justin S.; Moran, Amy L.

2012-01-01

Egg size is one of the fundamental parameters in the life histories of marine organisms. However, few studies have examined the relationships among egg size, composition, and energetic content in a phylogenetically controlled context. We investigated the associations among egg size, composition, and energy using a comparative system, geminate species formed by the closure of the Central American Seaway. We examined western Atlantic (WA) and eastern Pacific (EP) species in three echinoid genera, Echinometra, Eucidaris, and Diadema. In the genus with the largest difference in egg size between geminates (Echinometra), the eggs of WA species were larger, lipid rich and protein poor compared to the smaller eggs of their EP geminate. In addition, the larger WA eggs had significantly greater total egg energy and summed biochemical constituents yet significantly lower egg energy density (energy-per-unit-volume). However, the genera with smaller (Eucidaris) or no (Diadema) differences in egg size were not significantly different in summed biochemical constituents, total egg energy, or energy density. Theoretical models generally assume a strong tradeoff between egg size and fecundity that limits energetic investment and constrains life history evolution. We show that even among closely-related taxa, large eggs cannot be assumed to be scaled-up small eggs either in terms of energy or composition. Although our data comes exclusively from echinoid echinoderms, this pattern may be generalizable to other marine invertebrate taxa. Because egg composition and egg size do not necessarily evolve in lockstep, selective factors such as sperm limitation could act on egg volume without necessarily affecting maternal or larval energetics. PMID:22911821

Partial pedigree analysis of the segregation of yeast mitochondrial genes during vegetative reproduction.

PubMed

Waxman, M F; Birk, C W

1982-08-01

A three-factor cross of Saccharomyces cerevisiae involving the cap1, ery1, and oli1 loci was done, with partial pedigree analyses of 117 zygotes. First, second, and third buds were removed and the genotypes of their diploid progeny determined, along with those of the residual zygote mother cell. Results were analyzed in terms of frequencies of individual alleles and of recombinant genotypes in the dividing cells. There is a gradual increase in the frequency of homoplasmic cells and in gene frequency variance during these three generations, as would result from stochastic partitioning of mtDNA molecules between mother and bud, probably coupled with random drift of gene frequencies in interphase cells. These phenomena are more pronounced for buds than for mothers, suggesting that buds receive a smaller sample of molecules. End buds are more likely to be homoplasmic and have a lower frequency of recombinant genotypes than do central buds; an end bud is particularly enriched in alleles contributed by the parent that formed that end of the zygote. Zygotes with first central buds produce clones with a higher recombination frequency than do those with first end buds. These results confirm previous studies and suggest that mixing of parental genotypes occurs first in the center of the zygote. If segregation were strictly random, the number of segregating units would have to be much smaller than the number of mtDNA molecules in the zygote. On the other hand, there is no evidence for a region of the molecule ("attachment point") which segregates deterministically.

The effects of visual crowding, text size, and positional uncertainty on text legibility at a glance.

PubMed

Dobres, Jonathan; Wolfe, Benjamin; Chahine, Nadine; Reimer, Bryan

2018-07-01

Reading at a glance, once a relatively infrequent mode of reading, is becoming common. Mobile interaction paradigms increasingly dominate the way in which users obtain information about the world, which often requires reading at a glance, whether from a smartphone, wearable device, or in-vehicle interface. Recent research in these areas has shown that a number of factors can affect text legibility when words are briefly presented in isolation. Here we expand upon this work by examining how legibility is affected by more crowded presentations. Word arrays were combined with a lexical decision task, in which the size of the text elements and the inter-line spacing (leading) between individual items were manipulated to gauge their relative impacts on text legibility. In addition, a single-word presentation condition that randomized the location of presentation was compared with previous work that held position constant. Results show that larger text was more legible than smaller text. Wider leading significantly enhanced legibility as well, but contrary to expectations, wider leading did not fully counteract decrements in legibility at smaller text sizes. Single-word stimuli presented with random positioning were more difficult to read than stationary counterparts from earlier studies. Finally, crowded displays required much greater processing time compared to single-word displays. These results have implications for modern interface design, which often present interactions in the form of scrollable and/or selectable lists. The present findings are of practical interest to the wide community of graphic designers and interface engineers responsible for developing our interfaces of daily use. Copyright © 2018 Elsevier Ltd. All rights reserved.

Using a million cell simulation of the cerebellum: network scaling and task generality.

PubMed

Li, Wen-Ke; Hausknecht, Matthew J; Stone, Peter; Mauk, Michael D

2013-11-01

Several factors combine to make it feasible to build computer simulations of the cerebellum and to test them in biologically realistic ways. These simulations can be used to help understand the computational contributions of various cerebellar components, including the relevance of the enormous number of neurons in the granule cell layer. In previous work we have used a simulation containing 12000 granule cells to develop new predictions and to account for various aspects of eyelid conditioning, a form of motor learning mediated by the cerebellum. Here we demonstrate the feasibility of scaling up this simulation to over one million granule cells using parallel graphics processing unit (GPU) technology. We observe that this increase in number of granule cells requires only twice the execution time of the smaller simulation on the GPU. We demonstrate that this simulation, like its smaller predecessor, can emulate certain basic features of conditioned eyelid responses, with a slight improvement in performance in one measure. We also use this simulation to examine the generality of the computation properties that we have derived from studying eyelid conditioning. We demonstrate that this scaled up simulation can learn a high level of performance in a classic machine learning task, the cart-pole balancing task. These results suggest that this parallel GPU technology can be used to build very large-scale simulations whose connectivity ratios match those of the real cerebellum and that these simulations can be used guide future studies on cerebellar mediated tasks and on machine learning problems. Copyright © 2012 Elsevier Ltd. All rights reserved.

Body centre of mass movement in the sound horse.

PubMed

Buchner, H H; Obermüller, S; Scheidl, M

2000-11-01

The body centre of mass (BCM) is a key factor in the analysis of equine locomotion, as its position and movement determines the distribution and magnitude of loads on the limbs. In this study, the three-dimensional (3D) movement of the BCM in walking and trotting horses was assessed using a kinematic, segmental method. Thirty markers representing 20 body segments were recorded in 12 sound horses while standing, walking and trotting on a treadmill using a high-speed video system. Based on segmental inertial data, 3D positions of the segmental centres of mass as well as the total BCM were calculated. The position within the trunk during square standing and the movements of the BCM were determined for the three planes. The position of the BCM in the standing horse is presented relative to external reference points. At the trot, vertical displacement amplitude of the BCM amounted to 53 (6) mm as mean (sd), which was 27% smaller than external trunk movement. Medio-lateral displacement amplitude of the BCM was 19 (4) mm, 34% less than trunk amplitude. Sagittal forward-backward oscillations of the BCM independent from general forward movement were 13 (3) mm, being 24% less than trunk movements. At the walk, vertical, medio-lateral and sagittal BCM movements were smaller than trunk movements by 43, 65 and 65% respectively. The results show reduced and efficient BCM movements compared to the trunk and form a basis for the assessment of various clinical conditions such as lameness, the influence of a rider and various dressage performances. Copyright 2000 Harcourt Publishers Ltd.

Design of gefitinib-loaded poly (l-lactic acid) microspheres via a supercritical anti-solvent process for dry powder inhalation.

PubMed

Lin, Qing; Liu, Guijin; Zhao, Ziyi; Wei, Dongwei; Pang, Jiafeng; Jiang, Yanbin

2017-10-30

To develop a safer, more stable and potent formulation of gefitinib (GFB), micro-spheres of GFB encapsulated into poly (l-lactic acid) (PLLA) have been prepared by supercritical anti-solvent (SAS) technology in this study. Operating factors were optimized using a selected OA 16 (4 5 ) orthogonal array design, and the properties of the raw material and SAS processed samples were characterized by different methods The results show that the GFB-loaded PLLA particles prepared were spherical, having a smaller and narrower particle size compared with raw GFB. The optimal GFB-loaded PLLA sample was prepared with less aggregation, highest GFB loading (15.82%) and smaller size (D 50 =2.48μm, which meets the size of dry powder inhalers). The results of XRD and DSC indicate that GFB is encapsulated into PLLA matrix in a polymorphic form different from raw GFB. FT-IR results show that the chemical structure of GFB does not change after the SAS process. The results of in vitro release show that the optimal sample release was slower compared with raw GFB particles. Moreover, the results of in vitro anti-cancer trials show that the optimal sample had a higher cytotoxicity than raw GFB. After blending with sieved lactose, the flowability and aerosolization performance of the optimal sample for DPI were improved, with angle of repose, emitted dose and fine particles fractions from 38.4° to 23°, 63.21% to >90%, 23.37% to >30%, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

The formation of chondrules at high gas pressures in the solar nebula.

PubMed

Galy, A; Young, E D; Ash, R D; O'Nions, R K

2000-12-01

High-precision magnesium isotope measurements of whole chondrules from the Allende carbonaceous chondrite meteorite show that some aluminum-rich Allende chondrules formed at or near the time of formation of calcium-aluminum-rich inclusions and that some others formed later and incorporated precursors previously enriched in magnesium-26. Chondrule magnesium-25/magnesium-24 correlates with [magnesium]/[aluminum] and size, the aluminum-rich, smaller chondrules being the most enriched in the heavy isotopes of magnesium. These relations imply that high gas pressures prevailed during chondrule formation in the solar nebula.

Ultrasound assisted deposition of silica coatings on titanium

NASA Astrophysics Data System (ADS)

Kaş, Recep; Ertaş, Fatma Sinem; Birer, Özgür

2012-10-01

We present a novel ultrasound assisted method for silica coating of titanium surfaces. The coatings are formed by “smashing” silica nanoparticles onto activated titanium surface in solution using intense ultrasonic field. Homogeneous silica coatings are formed by deposition of dense multiple layers of silica nanoparticles. Since the nanoparticles also grow during the reaction, the layers of the coatings have smaller particles on the substrate and larger particles towards the surface. The thickness of the coatings can be controlled with several experimental parameters. Silica layers with thickness over 200 nm are readily obtained.

Scattering and Absorption Properties of Polydisperse Wavelength-sized Particles Covered with Much Smaller Grains

NASA Technical Reports Server (NTRS)

Dlugach, Jana M.; Mishchenko, Michael I.; Mackowski, Daniel W.

2012-01-01

Using the results of direct, numerically exact computer solutions of the Maxwell equations, we analyze scattering and absorption characteristics of polydisperse compound particles in the form of wavelength-sized spheres covered with a large number of much smaller spherical grains.The results pertain to the complex refractive indices1.55 + i0.0003,1.55 + i0.3, and 3 + i0.1. We show that the optical effects of dusting wavelength-sized hosts by microscopic grains can vary depending on the number and size of the grains as well as on the complex refractive index. Our computations also demonstrate the high efficiency of the new superposition T-matrix code developed for use on distributed memory computer clusters.

Minimizing Concentration Effects in Water-Based, Laminar-Flow Condensation Particle Counters

PubMed Central

Lewis, Gregory S.; Hering, Susanne V.

2013-01-01

Concentration effects in water condensation systems, such as used in the water-based condensation particle counter, are explored through numeric modeling and direct measurements. Modeling shows that the condensation heat release and vapor depletion associated with particle activation and growth lowers the peak supersaturation. At higher number concentrations, the diameter of the droplets formed is smaller, and the threshold particle size for activation is higher. This occurs in both cylindrical and parallel plate geometries. For water-based systems we find that condensational heat release is more important than is vapor depletion. We also find that concentration effects can be minimized through use of smaller tube diameters, or more closely spaced parallel plates. Experimental measurements of droplet diameter confirm modeling results. PMID:24436507

Cognitive factors in subjective stabilization of the visual world.

PubMed

Bridgeman, B

1981-08-01

If an eye movement signal is fed through a galvanic mirror, to move a projected image which a subject is inspecting, prominent objects in the image may seem to jiggle or jump with the the eye when the gain is just below the threshold for detecting a jump of the entire image (Brune and Lücking 1969). We have refined and extended this observation with both naive and practiced subjects, finding results which contradict all of the current theories about the mechanism of stabilization of the visual world and suggest that cognitive factors in perception important influences on the stabilization process. Using this method with a paired photocell system to detect horizontal eye movements, some subjects saw a prominent object in the display jump slightly while the rest of the scene remained stable. The task was done first with landscape slides, then repeated with Escher prints where two sets of alternating figures completely filled the image. Subjects could concentrate on one set of forms as the "figure" and the other as the "ground", and reverse the two at will. In a majority of practiced subjects and in smaller proportion of naive subjects, motion of part of the "figure" was seen regardless of which alternative set of forms constituted it. Reversibility of the effect controlled for influence of object size, brightness, etc. in inducing the selective jump. These and related observations show that cognitive or attentional variables are as important as image properties or gain alone in determining subjective stabilization of the visual world, though current theories (inflow, outflow, cancellation, etc.) consider image position to be simple variable. Another experiment showed that image movement on the retina during saccades cannot explain saccadic suppression of displacement.

Reconfigurable Processing Module

NASA Technical Reports Server (NTRS)

Somervill, Kevin; Hodson, Robert; Jones, Robert; Williams, John

2005-01-01

To accommodate a wide spectrum of applications and technologies, NASA s Exploration System's Missions Directorate has called for reconfigurable and modular technologies to support future missions to the moon and Mars. In response, Langley Research Center is leading a program entitled Reconfigurable Scaleable Computing (RSC) that is centered on the development of FPGA-based computing resources in a stackable form factor. This paper details the architecture and implementation of the Reconfigurable Processing Module (RPM), which is the key element of the RSC system. The RPM is an FPGA-based, space-qualified printed circuit assembly leveraging terrestrial/commercial design standards into the space applications domain. The form factor is similar to, and backwards compatible with, the PCI-104 standard utilizing only the PCI interface. The size is expanded to accommodate the required functionality while still better than 30% smaller than a 3U CompactPCI(TradeMark)card and without the overhead of the backplane. The architecture is built around two FPGA devices, one hosting PCI and memory interfaces, and another hosting mission application resources; both of which are connected with a high-speed data bus. The PCI interface FPGA provides access via the PCI bus to onboard SDRAM, flash PROM, and the application resources; both configuration management as well as runtime interaction. The reconfigurable FPGA, referred to as the Application FPGA - or simply "the application" - is a radiation-tolerant Xilinx Virtex-4 FX60 hosting custom application specific logic or soft microprocessor IP. The RPM implements various SEE mitigation techniques including TMR, EDAC, and configuration scrubbing of the reconfigurable FPGA. Prototype hardware and formal modeling techniques are used to explore the performability trade space. These models provide a novel way to calculate quality-of-service performance measures while simultaneously considering fault-related behavior due to SEE soft errors.

Dynamics of protein aggregation and oligomer formation governed by secondary nucleation

NASA Astrophysics Data System (ADS)

Michaels, Thomas C. T.; Lazell, Hamish W.; Arosio, Paolo; Knowles, Tuomas P. J.

2015-08-01

The formation of aggregates in many protein systems can be significantly accelerated by secondary nucleation, a process where existing assemblies catalyse the nucleation of new species. In particular, secondary nucleation has emerged as a central process controlling the proliferation of many filamentous protein structures, including molecular species related to diseases such as sickle cell anemia and a range of neurodegenerative conditions. Increasing evidence suggests that the physical size of protein filaments plays a key role in determining their potential for deleterious interactions with living cells, with smaller aggregates of misfolded proteins, oligomers, being particularly toxic. It is thus crucial to progress towards an understanding of the factors that control the sizes of protein aggregates. However, the influence of secondary nucleation on the time evolution of aggregate size distributions has been challenging to quantify. This difficulty originates in large part from the fact that secondary nucleation couples the dynamics of species distant in size space. Here, we approach this problem by presenting an analytical treatment of the master equation describing the growth kinetics of linear protein structures proliferating through secondary nucleation and provide closed-form expressions for the temporal evolution of the resulting aggregate size distribution. We show how the availability of analytical solutions for the full filament distribution allows us to identify the key physical parameters that control the sizes of growing protein filaments. Furthermore, we use these results to probe the dynamics of the populations of small oligomeric species as they are formed through secondary nucleation and discuss the implications of our work for understanding the factors that promote or curtail the production of these species with a potentially high deleterious biological activity.

Dynamics of protein aggregation and oligomer formation governed by secondary nucleation

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

Michaels, Thomas C. T., E-mail: tctm3@cam.ac.uk; Lazell, Hamish W.; Arosio, Paolo

2015-08-07

The formation of aggregates in many protein systems can be significantly accelerated by secondary nucleation, a process where existing assemblies catalyse the nucleation of new species. In particular, secondary nucleation has emerged as a central process controlling the proliferation of many filamentous protein structures, including molecular species related to diseases such as sickle cell anemia and a range of neurodegenerative conditions. Increasing evidence suggests that the physical size of protein filaments plays a key role in determining their potential for deleterious interactions with living cells, with smaller aggregates of misfolded proteins, oligomers, being particularly toxic. It is thus crucial tomore » progress towards an understanding of the factors that control the sizes of protein aggregates. However, the influence of secondary nucleation on the time evolution of aggregate size distributions has been challenging to quantify. This difficulty originates in large part from the fact that secondary nucleation couples the dynamics of species distant in size space. Here, we approach this problem by presenting an analytical treatment of the master equation describing the growth kinetics of linear protein structures proliferating through secondary nucleation and provide closed-form expressions for the temporal evolution of the resulting aggregate size distribution. We show how the availability of analytical solutions for the full filament distribution allows us to identify the key physical parameters that control the sizes of growing protein filaments. Furthermore, we use these results to probe the dynamics of the populations of small oligomeric species as they are formed through secondary nucleation and discuss the implications of our work for understanding the factors that promote or curtail the production of these species with a potentially high deleterious biological activity.« less

Chronic hemodynamic overload of the atria is an important factor for gap junction remodeling in human and rat hearts.

PubMed

Rucker-Martin, Catherine; Milliez, Paul; Tan, Sisareuth; Decrouy, Xavier; Recouvreur, Michel; Vranckx, Roger; Delcayre, Claude; Renaud, Jean-François; Dunia, Irene; Segretain, Dominique; Hatem, Stéphane N

2006-10-01

The expression and distribution of connexins is abnormal in a number of cardiac diseases, including atrial fibrillation, and is believed to favor conduction slowing and arrhythmia. Here, we studied the role of atrial structural remodeling in the disorganization of gap junctions and whether redistributed connexins can form new functional junction channels. Expression of connexin-43 (Cx43) was characterized by immunoblotting and immunohistochemistry in human right atrial specimens and in rat atria after myocardial infarction (MI). Gap junctions were studied by electron and 3-D microscopy, and myocyte-myocyte coupling was determined by Lucifer yellow dye transfer. In both chronically hemodynamically overloaded human atria in sinus rhythm and in dilated atria from MI-rats, Cx43 were dephosphorylated and redistributed from the intercalated disc to the lateral cell membranes as observed during atrial fibrillation. In MI-rats, the gap junctions at the intercalated disc were smaller (20% decrease) and contained very little Cx43 (0 or 1 gold particle vs. 42 to 98 in sham-operated rats). In the lateral membranes of myocytes, numerous connexon aggregates comprising non-phosphorylated Cx43 were observed. These connexon aggregates were in no case assembled into gap junction plaque-like structures. However, N-cadherin was well organized in the intercalated disc. There was very little myocyte-myocyte coupling in MI-rat atria and no myocyte-fibroblast coupling. Regression of the atrial remodeling was associated with the normalization of Cx43 localization. Structural alteration of the atrial myocardium is an important factor in the disorganization of connexins and gap junction. Moreover, redistributed Cx43 do not form junction channels.

Spider phobia is associated with decreased left amygdala volume: a cross-sectional study

PubMed Central

2013-01-01

Background Evidence from animal and human studies imply the amygdala as the most critical structure involved in processing of fear-relevant stimuli. In phobias, the amygdala seems to play a crucial role in the pathogenesis and maintenance of the disorder. However, the neuropathology of specific phobias remains poorly understood. In the present study, we investigated whether patients with spider phobia show altered amygdala volumes as compared to healthy control subjects. Methods Twenty female patients with spider phobia and twenty age-matched healthy female controls underwent magnetic resonance imaging to investigate amygdala volumes. The amygdalae were segmented using an automatic, model-based segmentation tool (FSL FIRST). Differences in amygdala volume were investigated by multivariate analysis of covariance with group as between-subject factor and left and right amygdala as dependent factors. The relation between amygdala volume and clinical features such as symptom severity, disgust sensitivity, trait anxiety and duration of illness was investigated by Spearman correlation analysis. Results Spider phobic patients showed significantly smaller left amygdala volume than healthy controls. No significant difference in right amygdala volume was detected. Furthermore, the diminished amygdala size in patients was related to higher symptom severity, but not to higher disgust sensitivity or trait anxiety and was independent of age. Conclusions In summary, the results reveal a relation between higher symptom severity and smaller left amygdala volume in patients with spider phobia. This relation was independent of other potential confounders such as the disgust sensitivity or trait anxiety. The findings suggest that greater spider phobic fear is associated with smaller left amygdala. However, the smaller left amygdala volume may either stand for a higher vulnerability to develop a phobic disorder or emerge as a consequence of the disorder. PMID:23442196

Magnitude of pseudopotential localization errors in fixed node diffusion quantum Monte Carlo

DOE PAGES

Kent, Paul R.; Krogel, Jaron T.

2017-06-22

Growth in computational resources has lead to the application of real space diffusion quantum Monte Carlo to increasingly heavy elements. Although generally assumed to be small, we find that when using standard techniques, the pseudopotential localization error can be large, on the order of an electron volt for an isolated cerium atom. We formally show that the localization error can be reduced to zero with improvements to the Jastrow factor alone, and we define a metric of Jastrow sensitivity that may be useful in the design of pseudopotentials. We employ an extrapolation scheme to extract the bare fixed node energymore » and estimate the localization error in both the locality approximation and the T-moves schemes for the Ce atom in charge states 3+/4+. The locality approximation exhibits the lowest Jastrow sensitivity and generally smaller localization errors than T-moves although the locality approximation energy approaches the localization free limit from above/below for the 3+/4+ charge state. We find that energy minimized Jastrow factors including three-body electron-electron-ion terms are the most effective at reducing the localization error for both the locality approximation and T-moves for the case of the Ce atom. Less complex or variance minimized Jastrows are generally less effective. Finally, our results suggest that further improvements to Jastrow factors and trial wavefunction forms may be needed to reduce localization errors to chemical accuracy when medium core pseudopotentials are applied to heavy elements such as Ce.« less

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

Kent, Paul R.; Krogel, Jaron T.

Growth in computational resources has lead to the application of real space diffusion quantum Monte Carlo to increasingly heavy elements. Although generally assumed to be small, we find that when using standard techniques, the pseudopotential localization error can be large, on the order of an electron volt for an isolated cerium atom. We formally show that the localization error can be reduced to zero with improvements to the Jastrow factor alone, and we define a metric of Jastrow sensitivity that may be useful in the design of pseudopotentials. We employ an extrapolation scheme to extract the bare fixed node energymore » and estimate the localization error in both the locality approximation and the T-moves schemes for the Ce atom in charge states 3+/4+. The locality approximation exhibits the lowest Jastrow sensitivity and generally smaller localization errors than T-moves although the locality approximation energy approaches the localization free limit from above/below for the 3+/4+ charge state. We find that energy minimized Jastrow factors including three-body electron-electron-ion terms are the most effective at reducing the localization error for both the locality approximation and T-moves for the case of the Ce atom. Less complex or variance minimized Jastrows are generally less effective. Finally, our results suggest that further improvements to Jastrow factors and trial wavefunction forms may be needed to reduce localization errors to chemical accuracy when medium core pseudopotentials are applied to heavy elements such as Ce.« less

Formation and growth of embryos of the Earth-Moon system

NASA Astrophysics Data System (ADS)

Ipatov, Sergei I.

2016-07-01

Galimov and Krivtsov [1] made computer simulations of the formation of the embryos of the Earth and the Moon as a result of contraction of a rarefied condensation. The angular momentum needed for such contraction could not be acquired during formation of the condensation from a protoplanetary disk. Using the formulas presented in [2], we obtained that the angular momentum of the present Earth-Moon system could be acquired at a collision of two rarefied condensations with a total mass not smaller than 0.1M_{e}, where M_{e} is the Earth mass. In principle, the angular momentum of the condensation needed for formation of the Earth-Moon system could be acquired by accumulation only of small objects, but for such model, the parental condensations of Venus and Mars could also get the angular momentum that was enough for formation of large satellites. Probably, the condensations that contracted and formed the embryos of the terrestrial planets other than the Earth did not collide with massive condensations, and therefore they did not get a large enough angular momentum needed to form massive satellites. The embryos formed as a result of contraction of the condensation grew by accumulation of solid planetesimals. The mass of the rarefied condensation that was a parent for the embryos of the Earth and the Moon could be relatively small (0.02M_{e} or even less), if we take into account the growth of the angular momentum of the embryos at the time when they accumulated planetesimals. There could be also the second main collision of the parental rarefied condensation with another condensation, at which the radius of the Earth's embryo condensation was smaller than the semi-major axis of the orbit of the Moon's embryo. The second main collision (or a series of similar collisions) could change the tilt of the Earth to its present value. For large enough eccentricities of planetesimals, the effective radii of proto-Earth and proto-Moon were proportional to r (where r is the radius of a considered embryo), and at the growth of the mass of the Earth's embryo by 10 times, the mass of the Moon's embryo increased by a factor of 1.43 and 1.31 at the ratio k_d of the density of the growing Moon to that of the growing Earth equal to its present value (k_d=0.6) and for equal densities (k_d=1), respectively. For the case of small relative velocities of planetesimals, effective radii of the embryos are proportional to r^2, and at the growth of the Earth's embryo mass by 10 times, the Moon's embryo mass increased by a factor of 1.051 and 1.044 at k_d=0.6 and k_d=1, respectively. [1] Galimov E.M., Krivtsov A.M.: Origin of the Moon. New concept. / De Gruyter. Berlin. 2012. 168 p. [2] Ipatov S.I.: Mon. Not. R. Astron. Soc., 2010, vol. 403, pp. 405-414.

Shark teeth as edged weapons: serrated teeth of three species of selachians.

PubMed

Moyer, Joshua K; Bemis, William E

2017-02-01

Prior to European contact, South Pacific islanders used serrated shark teeth as components of tools and weapons. They did this because serrated shark teeth are remarkably effective at slicing through soft tissues. To understand more about the forms and functions of serrated shark teeth, we examined the morphology and histology of tooth serrations in three species: the Tiger Shark (Galeocerdo cuvier), Blue Shark (Prionace glauca), and White Shark (Carcharodon carcharias). We show that there are two basic types of serrations. A primary serration consists of three layers of enameloid with underlying dentine filling the serration's base. All three species studied have primary serrations, although the dentine component differs (orthodentine in Tiger and Blue Sharks; osteodentine in the White Shark). Smaller secondary serrations are found in the Tiger Shark, formed solely by enameloid with no contribution from underlying dentine. Secondary serrations are effectively "serrations within serrations" that allow teeth to cut at different scales. We propose that the cutting edges of Tiger Shark teeth, equipped with serrations at different scales, are linked to a diet that includes large, hard-shelled prey (e.g., sea turtles) as well as smaller, softer prey such as fishes. We discuss other aspects of serration form and function by making analogies to man-made cutting implements, such as knives and saws. Copyright © 2016 Elsevier GmbH. All rights reserved.

STAR FORMATION AT Z = 2.481 IN THE LENSED GALAXY SDSS J1110+6459: STAR FORMATION DOWN TO 30 PARSEC SCALES.

PubMed

Johnson, Traci L; Rigby, Jane R; Sharon, Keren; Gladders, Michael D; Florian, Michael; Bayliss, Matthew B; Wuyts, Eva; Whitaker, Katherine E; Livermore, Rachael; Murray, Katherine T

2017-07-10

We present measurements of the surface density of star formation, the star-forming clump luminosity function, and the clump size distribution function, for the lensed galaxy SGAS J111020.0+645950.8 at a redshift of z =2.481. The physical size scales that we probe, radii r = 30-50 pc, are considerably smaller scales than have yet been studied at these redshifts. The star formation surface density we find within these small clumps is consistent with surface densities measured previously for other lensed galaxies at similar redshift. Twenty-two percent of the rest-frame ultraviolet light in this lensed galaxy arises from small clumps, with r <100 pc. Within the range of overlap, the clump luminosity function measured for this lensed galaxy is remarkably similar to those of z ∼ 0 galaxies. In this galaxy, star-forming regions smaller than 100 pc-physical scales not usually resolved at these redshifts by current telescopes-are important locations of star formation in the distant universe. If this galaxy is representative, this may contradict the theoretical picture in which the critical size scale for star formation in the distant universe is of order 1 kiloparsec. Instead, our results suggest that current telescopes have not yet resolved the critical size scales of star-forming activity in galaxies over most of cosmic time.

12 CFR Appendix H to Part 1026 - Closed-End Model Forms and Clauses

Code of Federal Regulations, 2014 CFR

2014-01-01

... change (frequency). • [Your interest rate cannot increase or decrease more than __ percentage points at... over the term of the loan. How Your Payment Can Change • Your payment can change (frequency) based on... common periods occur with equal frequency, the smaller of such common periods shall be the unit-period...

Ponytails & Death-Ray Looks: A Review of Research on Relational Aggression among Adolescent Girls

ERIC Educational Resources Information Center

Fisher, Glenn L.

2010-01-01

Relational aggression (RA) involves either indirect, verbal, or covert acts with the intent to humiliate, exclude peers from groups, and/or damage a peer's reputation and social status. RA is believed to be particularly devastating psychologically for adolescent girls, as they tend to form smaller and more intimate social groups. Unfortunately, RA…

Decimals Are Not Processed Automatically, Not Even as Being Smaller than One

ERIC Educational Resources Information Center

Kallai, Arava Y.; Tzelgov, Joseph

2014-01-01

Common fractions have been found to be processed intentionally but not automatically, which led to the conclusion that they are not represented holistically in long-term memory. However, decimals are more similar to natural numbers in their form and thus might be better candidates to be holistically represented by educated adults. To test this…

Estimating the Effects of Students' Social Networks: Does Attending a Norm-Enforcing School Pay Off?

ERIC Educational Resources Information Center

Carolan, Brian V.

2010-01-01

In an attempt to forge tighter social relations, small school reformers advocate school designs intended to create smaller, more trusting, and more collaborative settings. These efforts to enhance students' social capital in the form of social closure are ultimately tied to improving academic outcomes. Using data derived from ELS: 2002, this study…

Modeling and Simulation of An Adaptive Neuro-Fuzzy Inference System (ANFIS) for Mobile Learning

ERIC Educational Resources Information Center

Al-Hmouz, A.; Shen, Jun; Al-Hmouz, R.; Yan, Jun

2012-01-01

With recent advances in mobile learning (m-learning), it is becoming possible for learning activities to occur everywhere. The learner model presented in our earlier work was partitioned into smaller elements in the form of learner profiles, which collectively represent the entire learning process. This paper presents an Adaptive Neuro-Fuzzy…

Suicide Risk among Violent and Sexual Criminal Offenders

ERIC Educational Resources Information Center

Webb, Roger T.; Shaw, Jenny; Stevens, Hanne; Mortensen, Preben B.; Appleby, Louis; Qin, Ping

2012-01-01

Risk of suicide in people who have perpetrated specific forms of violent or sexual criminal offenses has not been quantified accurately or precisely. Also, gender comparisons have not been possible due to sparse data problems in the smaller studies that have been conducted to date. We therefore aimed to estimate these effects in the whole Danish…

Forms of Cooperative Learning in Language Teaching in Slovenian Language Classes at the Primary School Level

ERIC Educational Resources Information Center

Vrhovec, Alenka Rot

2015-01-01

In the Slovenian language syllabus, teachers are recommended to provide a greater share of group work during class. During types of learning such as cooperative learning in smaller groups or pairs, students actively develop communicative competence. The present article presents a survey that attempted to determine whether teachers from the first…

Band structure and thermoelectric properties of half-Heusler semiconductors from many-body perturbation theory

NASA Astrophysics Data System (ADS)

Zahedifar, Maedeh; Kratzer, Peter

2018-01-01

Various ab initio approaches to the band structure of A NiSn and A CoSb half-Heusler compounds (A = Ti, Zr, Hf) are compared and their consequences for the prediction of thermoelectric properties are explored. Density functional theory with the generalized-gradient approximation (GGA), as well as the hybrid density functional HSE06 and ab initio many-body perturbation theory in the form of the G W0 approach, are employed. The G W0 calculations confirm the trend of a smaller band gap (0.75 to 1.05 eV) in A NiSn compared to the A CoSb compounds (1.13 to 1.44 eV) already expected from the GGA calculations. While in A NiSn materials the G W0 band gap is 20% to 50% larger than in HSE06, the fundamental gap of A CoSb materials is smaller in G W0 compared to HSE06. This is because G W0 , similar to PBE, locates the valence band maximum at the L point of the Brillouin zone, whereas it is at the Γ point in the HSE06 calculations. The differences are attributed to the observation that the relative positions of the d levels of the transition metal atoms vary among the different methods. Using the calculated band structures and scattering rates taking into account the band effective masses at the extrema, the Seebeck coefficients, thermoelectric power factors, and figures of merit Z T are predicted for all six half-Heusler compounds. Comparable performance is predicted for the n -type A NiSn materials, whereas clear differences are found for the p -type A CoSb materials. Using the most reliable G W0 electronic structure, ZrCoSb is predicted to be the most efficient material with a power factor of up to 0.07 W/(K2 m) at a temperature of 600 K. We find strong variations among the different ab initio methods not only in the prediction of the maximum power factor and Z T value of a given material, but also in comparing different materials to each other, in particular in the p -type thermoelectric materials. Thus we conclude that the most elaborate, but also most costly G W0 method is required to perform a reliable computational search for the optimum material.

Small field detector correction factors kQclin,Qmsr (fclin,fmsr) for silicon-diode and diamond detectors with circular 6 MV fields derived using both empirical and numerical methods.

PubMed

O'Brien, D J; León-Vintró, L; McClean, B

2016-01-01

The use of radiotherapy fields smaller than 3 cm in diameter has resulted in the need for accurate detector correction factors for small field dosimetry. However, published factors do not always agree and errors introduced by biased reference detectors, inaccurate Monte Carlo models, or experimental errors can be difficult to distinguish. The aim of this study was to provide a robust set of detector-correction factors for a range of detectors using numerical, empirical, and semiempirical techniques under the same conditions and to examine the consistency of these factors between techniques. Empirical detector correction factors were derived based on small field output factor measurements for circular field sizes from 3.1 to 0.3 cm in diameter performed with a 6 MV beam. A PTW 60019 microDiamond detector was used as the reference dosimeter. Numerical detector correction factors for the same fields were derived based on calculations from a geant4 Monte Carlo model of the detectors and the Linac treatment head. Semiempirical detector correction factors were derived from the empirical output factors and the numerical dose-to-water calculations. The PTW 60019 microDiamond was found to over-respond at small field sizes resulting in a bias in the empirical detector correction factors. The over-response was similar in magnitude to that of the unshielded diode. Good agreement was generally found between semiempirical and numerical detector correction factors except for the PTW 60016 Diode P, where the numerical values showed a greater over-response than the semiempirical values by a factor of 3.7% for a 1.1 cm diameter field and higher for smaller fields. Detector correction factors based solely on empirical measurement or numerical calculation are subject to potential bias. A semiempirical approach, combining both empirical and numerical data, provided the most reliable results.

Winning by a neck: tall giraffes avoid competing with shorter browsers.

PubMed

Cameron, Elissa Z; du Toit, Johan T

2007-01-01

With their vertically elongated body form, giraffes generally feed above the level of other browsers within the savanna browsing guild, despite having access to foliage at lower levels. They ingest more leaf mass per bite when foraging high in the tree, perhaps because smaller, more selective browsers deplete shoots at lower levels or because trees differentially allocate resources to promote shoot growth in the upper canopy. We erected exclosures around individual Acacia nigrescens trees in the greater Kruger ecosystem, South Africa. After a complete growing season, we found no differences in leaf biomass per shoot across height zones in excluded trees but significant differences in control trees. We conclude that giraffes preferentially browse at high levels in the canopy to avoid competition with smaller browsers. Our findings are analogous with those from studies of grazing guilds and demonstrate that resource partitioning can be driven by competition when smaller foragers displace larger foragers from shared resources. This provides the first experimental support for the classic evolutionary hypothesis that vertical elongation of the giraffe body is an outcome of competition within the browsing ungulate guild.

Au particle formation on the electron beam induced membrane

NASA Astrophysics Data System (ADS)

Choi, Seong Soo; Park, Myoung Jin; Han, Chul Hee; Oh, Sae-Joong; Kim, Sung-In; Park, Nam Kyou; Park, Doo-Jae; Choi, Soo Bong; Kim, Yong-Sang

2017-02-01

Recently the single molecules such as protein and deoxyribonucleic acid (DNA) have been successfully characterized by using a portable solidstate nanopore (MinION) with an electrical detection technique. However, there have been several reports about the high error rates of the fabricated nanopore device, possibly due to an electrical double layer formed inside the pore channel. The current DNA sequencing technology utilized is based on the optical detection method. In order to utilize the current optical detection technique, we will present the formation of the Au nano-pore with Au particle under the various electron beam irradiations. In order to provide the diffusion of Au atoms, a 2 keV electron beam irradiation has been performed During electron beam irradiations by using field emission scanning electron microscopy (FESEM), Au and C atoms would diffuse together and form the binary mixture membrane. Initially, the Au atoms diffused in the membrane are smaller than 1 nm, below the detection limit of the transmission electron microscopy (TEM), so that we are unable to observe the Au atoms in the formed membrane. However, after several months later, the Au atoms became larger and larger with expense of the smaller particles: Ostwald ripening. Furthermore, we also observe the Au crystalline lattice structure on the binary Au-C membrane. The formed Au crystalline lattice structures were constantly changing during electron beam imaging process due to Spinodal decomposition; the unstable thermodynamic system of Au-C binary membrane. The fabricated Au nanopore with an Au nanoparticle can be utilized as a single molecule nanobio sensor.

An investigation of application of the golden ratio and Fibonacci sequence in fashion design and pattern making

NASA Astrophysics Data System (ADS)

Kazlacheva, Z. I.

2017-10-01

The Golden ratio and Fibonacci sequence are used as proportions in design as symbols of beauty and harmony. That symbolism is a result of the strong connections in their mathematical nature. The Golden section is a number, introduced with Greek letter φ, which is found by dividing a line into two parts as the longer part divided by the smaller part is equal as the whole length of longer and smaller parts divided by the longer part. Fibonacci sequence is a series of numbers where every number is equal to the two numbers before it. An investigation of application of proportions based on the Golden ratio and Fibonacci sequence in the fashion design and pattern making of ladies’ clothing is the main aim of the paper. Based on the study it may be concluded that in fashion design and pattern making the Golden ratio and Fibonacci sequence can be used in creation of beautiful and harmonic forms directly or with the help of geometrical figures as: In directly use the Golden and Fibonacci numbers proportions can be in one and the same or different directions. In the application with the help of geometrical shapes the Golden and Fibonacci figures combine proportioning and form creation. The Golden and Fibonacci shapes can be used directly as forms or as frames of forms creation of elements and pieces. Its application can be in different directions and location according the bodice. The Golden section and Fibonacci sequence can combine proportions with other principles of design as symmetry, rhythm, etc.

Well-Preserved Impact Ejecta and Impact Melt-Rich Deposits in Terra Sabaea

NASA Image and Video Library

2017-01-12

This image of a well-preserved unnamed elliptical crater in Terra Sabaea, is illustrative of the complexity of ejecta deposits forming as a by-product of the impact process that shapes much of the surface of Mars. Here we see a portion of the western ejecta deposits emanating from a 10-kilometer impact crater that occurs within the wall of a larger, 60-kilometer-wide crater. In the central part is a lobe-shaped portion of the ejecta blanket from the smaller crater. The crater is elliptical not because of an angled (oblique) impact, but because it occurred on the steep slopes of the wall of a larger crater. This caused it to be truncated along the slope and elongated perpendicular to the slope. As a result, any impact melt from the smaller crater would have preferentially deposited down slope and towards the floor of the larger crater (towards the west). Within this deposit, we can see fine-scale morphological features in the form of a dense network of small ridges and pits. These crater-related pitted materials are consistent with volatile-rich impact melt-bearing deposits seen in some of the best-preserved craters on Mars (e.g., Zumba, Zunil, etc.). These deposits formed immediately after the impact event, and their discernible presence relate to the preservation state of the crater. This image is an attempt to visualize the complex formation and emplacement history of these enigmatic deposits formed by this elliptical crater and to understand its degradation history. http://photojournal.jpl.nasa.gov/catalog/PIA13078

Drug recrystallization using supercritical anti-solvent (SAS) process with impinging jets: Effect of process parameters

NASA Astrophysics Data System (ADS)

Careno, Stéphanie; Boutin, Olivier; Badens, Elisabeth

2012-03-01

The aim of this study is to improve mixing in supercritical anti-solvent process (SAS) with impinging jets in order to form finer particles of sulfathiazole, a poorly water-soluble drug. The influence of several process parameters upon the powder characteristics is studied. Parameters are jets' velocity (0.25 m s-1 to 25.92 m s-1), molar ratio solvent/CO2 (2.5% to 20%), temperature (313 K to 343 K), pressure (10 MPa to 20 MPa) and sulfathiazole concentration in the organic solution (0.5% to 1.8%). Two solvents are used: acetone and methanol. Smaller particles with a more homogeneous morphology are obtained from acetone solutions. For the smallest jets' velocity, corresponding to a non-atomized jet, the stable polymorphic form is obtained, pure or in mixture. At this velocity, pressure is the most influential parameter controlling the polymorphic nature of the powder formed. The pure stable polymorph is formed at 20 MPa. Concerning the particle size, the most influential parameters are temperature and sulfathiazole concentration. The use of impinging jets with different process parameters allows the crystallization of four polymorphs among the five known, and particle sizes are varied. This work demonstrates the studied device ability of the polymorph and the size control. A comparison with the classical SAS process shows that particle size, size distribution and morphology of particles crystallized with impinging jets are different from the ones obtained with classical SAS introduction device in similar operating conditions. Mean particle sizes are significantly smaller and size distributions are narrower with impinging jets device.

Evaluation of jojoba meal as a potential supplement in the diet of broiler breeder females during laying.

PubMed

Vermaut, S; De Coninck, K; Bruggeman, V; Onagbesan, O; Flo, G; Cokelaere, M; Decuypere, E

1999-05-01

1. This study was undertaken to investigate whether jojoba meal can be used as a food supplement during the laying period of chickens. 2. The size of eggs laid were smaller and the overall production rate was lower compared to control birds on food without jojoba meal supplementation. Furthermore, both ovary and oviduct weights were lower in jojoba fed birds. 3. This lowering of egg size and production rate was caused by factors present in jojoba which interfere with follicle growth, yolk deposition, progesterone production and the follicular maturation processes, resulting in the ovulation of smaller follicles and a lower ovulation rate.

Developmental variation in ecogeographic body proportions.

PubMed

Cowgill, Libby W; Eleazer, Courtney D; Auerbach, Benjamin M; Temple, Daniel H; Okazaki, Kenji

2012-08-01

While ecogeographic variation in adult human body proportions has been extensively explored, relatively less attention has been paid to the effect of Bergmann's and Allen's rules on human body shape during growth. The relationship between climate and immature body form is particularly important, as immature mortality is high, mechanisms of thermoregulation differ between young and mature humans, and immature body proportions fluctuate due to basic parameters of growth. This study explores changes in immature ecogeographic body proportions via analyses of anthropometric data from children included in Eveleth and Tanner's (1976) Worldwide Variation in Human Growth, as well as limb proportion measurements in eight different skeletal samples. Moderate to strong correlations exist between climatic data and immature stature, weight, BMI, and bi-iliac breadth; these relationships are as strong, if not stronger, in immature individuals as they are in adults. Correlations between climate and trunk height relative to stature are weak or nonexistent. Altitude also has significant effects on immature body form, with children from higher altitudes displaying smaller statures and lower body weights. Brachial and crural indices remain constant over the course of growth and display consistent, moderate correlations with latitude across ontogeny that are just as high as those detected in adults. The results of this study suggest that while some features of immature body form, such as bi-iliac breadth and intralimb indices, are strongly dictated by ecogeographic principles, other characteristics of immature body proportions are influenced by intrinsic and extrinsic factors such as nutrition and basic constraints of growth. Copyright © 2012 Wiley Periodicals, Inc.

Instability Mechanisms of Water-in-Oil Nanoemulsions with Phospholipids: Temporal and Morphological Structures.

PubMed

Sommerling, Jan-Hendrik; de Matos, Maria B C; Hildebrandt, Ellen; Dessy, Alberto; Kok, Robbert Jan; Nirschl, Hermann; Leneweit, Gero

2018-01-16

Many food preparations, pharmaceuticals, and cosmetics use water-in-oil (W/O) emulsions stabilized by phospholipids. Moreover, recent technological developments try to produce liposomes or lipid coated capsules from W/O emulsions, but are faced with colloidal instabilities. To explore these instability mechanisms, emulsification by sonication was applied in three cycles, and the sample stability was studied for 3 h after each cycle. Clearly identifiable temporal structures of instability provide evidence about the emulsion morphology: an initial regime of about 10 min is shown to be governed by coalescence after which Ostwald ripening dominates. Transport via molecular diffusion in Ostwald ripening is commonly based on the mutual solubility of the two phases and is therefore prohibited in emulsions composed of immiscible phases. However, in the case of water in oil emulsified by phospholipids, these form water-loaded reverse micelles in oil, which enable Ostwald ripening despite the low solubility of water in oil, as is shown for squalene. As is proved for the phospholipid dipalmitoylphosphatidylcholine (DPPC), concentrations below the critical aggregation concentration (CAC) form monolayers at the interfaces and smaller droplet sizes. In contrast, phospholipid concentrations above the CAC create complex multilayers at the interface with larger droplet sizes. The key factors for stable W/O emulsions in classical or innovative applications are first, the minimization of the phospholipids' capacity to form reversed micelles, and second, the adaption of the initial phospholipid concentration to the water content to enable an optimized coverage of phospholipids at the interfaces for the intended drop size.

Threshold and flavor effects in the renormalization group equations of the MSSM. II. Dimensionful couplings

NASA Astrophysics Data System (ADS)

Box, Andrew D.; Tata, Xerxes

2009-02-01

We reexamine the one-loop renormalization group equations (RGEs) for the dimensionful parameters of the minimal supersymmetric standard model (MSSM) with broken supersymmetry, allowing for arbitrary flavor structure of the soft SUSY-breaking parameters. We include threshold effects by evaluating the β-functions in a sequence of (nonsupersymmetric) effective theories with heavy particles decoupled at the scale of their mass. We present the most general form for high-scale, soft SUSY-breaking parameters that obtains if we assume that the supersymmetry-breaking mechanism does not introduce new intergenerational couplings. This form, possibly amended to allow additional sources of flavor-violation, serves as a boundary condition for solving the RGEs for the dimensionful MSSM parameters. We then present illustrative examples of numerical solutions to the RGEs. We find that in a SUSY grand unified theory with the scale of SUSY scalars split from that of gauginos and higgsinos, the gaugino mass unification condition may be violated by O(10%). As another illustration, we show that in mSUGRA, the rate for the flavor-violating ttilde 1→c Ztilde 1 decay obtained using the complete RGE solution is smaller than that obtained using the commonly used “single-step” integration of the RGEs by a factor 10-25, and so may qualitatively change expectations for topologies from top-squark pair production at colliders. Together with the RGEs for dimensionless couplings presented in a companion paper, the RGEs in Appendix 2 of this paper form a complete set of one-loop MSSM RGEs that include threshold and flavor-effects necessary for two-loop accuracy.

AIMAR survey on complex forms of bronchial asthma and COPD, their management and perception of critical issues.

PubMed

Donner, Claudio F; Visconti, Alberto

2014-01-01

The management of patients with complex forms of bronchial asthma and COPD is not usually addressed in the major international guidelines and management documents which exclusively address pure forms. AIMAR thus undertook a survey to obtain information about: a) the perceived frequency of complex forms of asthma/COPD in adult patients and in the elderly; b) patient management regarding the complex forms (focus on therapeutic goals and consequent treatment); c) the management problems perceived in diagnosis, management, monitoring, indices of appropriateness in pharmacological treatment and adherence to treatment. The survey consisted of 18 multiple choice questions, completed by means of a web-based electronic form published in internet. All the data and responses inserted in the system were checked on-line for coherence and completeness directly during the phase of insertion and each participant had one only possibility of participating. The data thus collected were memorized directly within a relational database, based on consolidated open-source MySQL technology, and thus were immediately available for examination also during the course of the survey. Access to the data, mediated by a "back office" system of interrogation and report, enabled constant monitoring of the survey as it was being carried out, as well as extractions and verification, even on smaller data sets. The survey was carried out in the full month of December 2013 and first half of January 2014. A total of 252 questionnaires were collected from the following physician groups: pneumologists (n = 180), general practitioners (GPs) (n = 32), allergologists (n = 8), internal medicine specialists (n = 20), other specialists (n = 12). Complex forms of bronchial asthma and COPD are frequently observed and considered present in variable percentages ranging from about 10% to about 50% of patients visited and considered typical of patients with a previous history of asthma. Risk factors such as smoking, obesity, bronchial hyperreactivity and genetic predisposition are considered important. Diagnosis is difficult solely on the basis of symptoms in approximately 50% of cases, and a previous history of asthma, history of spirometry and presence of allergy are of help. Treating inflammation and reducing exacerbations are considered the key therapeutic goals and the combination of inhaled corticosteroid (ICS) and long acting β2-agonist (LABA) and monotherapy with ICS are considered the fundamental pharmacological mode for treating patients with mixed forms of bronchial asthma and COPD. Treating with only a bronchodilator is considered to be moderately risky for this type of patient. The identification and management of mixed forms result more impeded by "logistic" aspects, e.g. long waiting lists and integration with the GP, than by aspects intrinsic to the disease management itself, e.g. selecting the assessment or interpreting the outcome of the instrumental examinations. Treatment continuity and the integration between GP and specialist are the factors that most limit the management of mixed forms in the stable phase.

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: PAINT OVERSPRAY ARRESTOR, FARR COMPANY RIGA-FLO 200

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than...

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: PAINT OVERSPRAY ARRESTOR, ATI OSM 200 SYSTEM

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than...

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: PAINT OVERSPRAY ARRESTOR, COLUMBUS INDUSTRIES SL-46B

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than...

Comprehensive health evaluation of workers in the ceramics industry.

PubMed Central

Huang, J; Shibata, E; Takeuchi, Y; Okutani, H

1993-01-01

A cross sectional study on ceramics workers in the Seto area of Japan was conducted to determine whether there are differences in the morbidity pattern and overall health among the working populations employed by different sized companies engaged in the ceramics industry. The study population consisted of 3324 male ceramics workers (age range 40-69) who participated in the Seto occupational health screening programme in 1990. The prevalences of pulmonary diseases (silicosis and tuberculosis) and findings of some nonpulmonary diseases were compared in terms of company size by categories of 1-19, 20-49, 50-99, and 100 or more employees. The values of various screening tests were subjected to principle component analysis to extract factors representing key indices of health state. The average factor scores stratified by company size were used to quantitatively evaluate the comprehensive health level. Both prevalence and multivariate analysis showed that the employees working for smaller companies had overall worse health. The smaller the company, the higher the prevalence and the lower the health scores for silicosis and pulmonary tuberculosis tended to be; significantly increased rates and lower health scores for hypertension, anaemia, and glucosuria among small companies were also found when compared with larger companies. The high morbidity of silicosis and pulmonary tuberculosis in smaller companies contributed most to the decline in the overall health level. PMID:8435343

Evolution of the Varrier autostereoscopic VR display: 2001-2007

NASA Astrophysics Data System (ADS)

Peterka, Tom; Kooima, Robert L.; Girado, Javier I.; Ge, Jinghua; Sandin, Daniel J.; DeFanti, Thomas A.

2007-02-01

Autostereoscopy (AS) is an increasingly valuable virtual reality (VR) display technology; indeed, the IS&T / SPIE Electronic Imaging Conference has seen rapid growth in the number and scope of AS papers in recent years. The first Varrier paper appeared at SPIE in 2001, and much has changed since then. What began as a single-panel prototype has grown to a full scale VR autostereo display system, with a variety of form factors, features, and options. Varrier is a barrier strip AS display system that qualifies as a true VR display, offering a head-tracked ortho-stereo first person interactive VR experience without the need for glasses or other gear to be worn by the user. Since Varrier's inception, new algorithmic and systemic developments have produced performance and quality improvements. Visual acuity has increased by a factor of 1.4X with new fine-resolution barrier strip linescreens and computational algorithms that support variable sub-pixel resolutions. Performance has improved by a factor of 3X using a new GPU shader-based sub-pixel algorithm that accomplishes in one pass what previously required three passes. The Varrier modulation algorithm that began as a computationally expensive task is now no more costly than conventional stereoscopic rendering. Interactive rendering rates of 60 Hz are now possible in Varrier for complex scene geometry on the order of 100K vertices, and performance is GPU bound, hence it is expected to continue improving with graphics card enhancements. Head tracking is accomplished with a neural network camera-based tracking system developed at EVL for Varrier. Multiple cameras capture subjects at 120 Hz and the neural network recognizes known faces from a database and tracks them in 3D space. New faces are trained and added to the database in a matter of minutes, and accuracy is comparable to commercially available tracking systems. Varrier supports a variety of VR applications, including visualization of polygonal, ray traced, and volume rendered data. Both AS movie playback of pre-rendered stereo frames and interactive manipulation of 3D models are supported. Local as well as distributed computation is employed in various applications. Long-distance collaboration has been demonstrated with AS teleconferencing in Varrier. A variety of application domains such as art, medicine, and science have been exhibited, and Varrier exists in a variety of form factors from large tiled installations to smaller desktop forms to fit a variety of space and budget constraints. Newest developments include the use of a dynamic parallax barrier that affords features that were inconceivable with a static barrier.

[Factors influencing the quality of life of elderly living in a pre-fabricated housing complex in the Sichuan earthquake area].

PubMed

Guo, Hong-Xia; Chen, Hong; Wong, Teresa Bik-Kwan Tsien; Chen, Qian; Au, May-Lan; Li, Yun

2012-02-01

The 2008 Sichuan Earthquake caused great damage to the environment and property. In the aftermath, many citizens were relocated to live in newly constructed prefabricated (prefab) communities. This paper explored the current quality of life (QOL) of elderly residents living in prefabricated communities in areas damaged by the Sichuan earthquake and identified factors of influence on QOL values. The ultimate objective was to provide evidence-based guidance for heath improvement measures. The authors used the short form WHOQOL-BREF to assess the quality of life of 191 elderly residents of prefabricated communities in the Sichuan Province 2008 earthquake zone. A Student's t-test, variance analysis, and stepwise multivariate regression methods were used to test the impact of various factors on QOL. Results indicate the self-assessed QOL of participants as good, although scores in the physical (average 56.2) and psychological (average 45.7) domains were significantly lower than the norm in China. Marital status, capital loss in the earthquake, number of children, level of perceived stress, income, interest, and family harmony each correlated with at least one of the short form WHOQOL-BREF domains in t-test and one-way analyses. After excluding for factor interaction effects using multivariate regression, we found interest, family harmony, monthly income and stress to be significant predictors of physical domain QOL, explaining 13.8% of total variance. Family harmony and interest explained 15.3% of total variance for psychological domain QOL; stress, marital status, family harmony, capital loss in the earthquake, number of children and interest explained 19.5% of total variance for social domain QOL; and stress, family harmony and interest explained 16.5% of total variance for environmental domain QOL. Family harmony and interest were significant factors across all domains, while others influenced a smaller proportion. Quality of life for elderly living in prefab communities should be improved. The authors hope study findings will increase awareness among healthcare providers regarding the quality of life of this vulnerable population. Study results suggest that key steps to promoting QOL in this population include improving family harmony, helping to cultivate well-rounded interests, alleviating economic stresses, providing necessary medical and psychological counseling services, and affording more social support.

Progression of cognitive impairment in stroke/TIA patients over 3 years.

PubMed

Sachdev, Perminder S; Lipnicki, Darren M; Crawford, John D; Wen, Wei; Brodaty, Henry

2014-12-01

To examine how cognitive deficits progress in the years following a stroke or transient ischaemic attack (TIA). A follow-up study, with neuropsychological and MRI assessments undertaken 3 years after baseline assessments made 3-6 months poststroke in 183 stroke/TIA patients and 97 healthy controls participating in the Sydney Stroke Study. Additional measures included cardiovascular risk factors and apolipoprotein E (APOE) genotype. Stroke/TIA patients had poorer cognitive function and more vascular risk factors than controls at baseline, but did not show greater decline in cognitive function over 3 years except for verbal memory. Patients with a subsequent stroke/TIA showed greater decline in global cognitive function and a number of domains. Rates of incident dementia were 5.9% per year in patients and 0.4% in controls. Both groups showed increased atrophy of the hippocampus, amygdala and whole brain, and an increase in white matter hyperintensities over 3 years; whole brain atrophy was greater in patients. Cognitive decline was greater in women and in those with smaller hippocampi at baseline. For patients without a subsequent stroke/TIA, those with smaller hippocampi or the APOE ε4 allele had greater global cognitive and verbal memory decline. In poststroke patients, cognitive decline was not greater than in comparison subjects, except for verbal memory, unless they had another stroke/TIA. However, dementia incidence was higher in patients, as might be expected from their poorer baseline cognitive functioning. Smaller hippocampi were associated with an increased risk of decline in memory, and APOE ε4 was a risk factor in those without a subsequent stroke/TIA. 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.

Seasonal prevalence and determinants of food insecurity in Iqaluit, Nunavut.

PubMed

Guo, Yang; Berrang-Ford, Lea; Ford, James; Lardeau, Marie-Pierre; Edge, Victoria; Patterson, Kaitlin; Harper, Sherilee L

2015-01-01

Background Food insecurity is an ongoing problem in the Canadian Arctic. Although most studies have focused on smaller communities, little is known about food insecurity in larger centres. Objectives This study aimed to estimate the prevalence of food insecurity during 2 different seasons in Iqaluit, the territorial capital of Nunavut, as well as identify associated risk factors. Designs A modified United States Department of Agriculture Food Security Survey was applied to 532 randomly selected households in September 2012 and 523 in May 2013. Chi-square tests and multivariable logistic regression were used to examine potential associations between food security and 9 risk factors identified in the literature. Results In September 2012, 28.7% of surveyed households in Iqaluit were food insecure, a rate 3 times higher than the national average, but lower than smaller Inuit communities in Nunavut. Prevalence of food insecurity in September 2012 was not significantly different in May 2013 (27.2%). When aggregating results from Inuit households from both seasons (May and September), food insecurity was associated with poor quality housing and reliance on income support (p<0.01). Unemployment and younger age of the person in charge of food preparation were also significantly associated with food insecurity. In contrast to previous research among Arctic communities, gender and consumption of country food were not positively associated with food security. These results are consistent with research describing high food insecurity across the Canadian Arctic. Conclusion The factors associated with food insecurity in Iqaluit differed from those identified in smaller communities, suggesting that experiences with, and processes of, food insecurity may differ between small communities and larger commercial centres. These results suggest that country food consumption, traditional knowledge and sharing networks may play a less important role in larger Inuit communities.

Seasonal prevalence and determinants of food insecurity in Iqaluit, Nunavut.

PubMed

Guo, Yang; Berrang-Ford, Lea; Ford, James; Lardeau, Marie-Pierre; Edge, Victoria; Patterson, Kaitlin; Harper, Sherilee L

2015-01-01

Food insecurity is an ongoing problem in the Canadian Arctic. Although most studies have focused on smaller communities, little is known about food insecurity in larger centres. This study aimed to estimate the prevalence of food insecurity during 2 different seasons in Iqaluit, the territorial capital of Nunavut, as well as identify associated risk factors. A modified United States Department of Agriculture Food Security Survey was applied to 532 randomly selected households in September 2012 and 523 in May 2013. Chi-square tests and multivariable logistic regression were used to examine potential associations between food security and 9 risk factors identified in the literature. In September 2012, 28.7% of surveyed households in Iqaluit were food insecure, a rate 3 times higher than the national average, but lower than smaller Inuit communities in Nunavut. Prevalence of food insecurity in September 2012 was not significantly different in May 2013 (27.2%). When aggregating results from Inuit households from both seasons (May and September), food insecurity was associated with poor quality housing and reliance on income support (p<0.01). Unemployment and younger age of the person in charge of food preparation were also significantly associated with food insecurity. In contrast to previous research among Arctic communities, gender and consumption of country food were not positively associated with food security. These results are consistent with research describing high food insecurity across the Canadian Arctic. The factors associated with food insecurity in Iqaluit differed from those identified in smaller communities, suggesting that experiences with, and processes of, food insecurity may differ between small communities and larger commercial centres. These results suggest that country food consumption, traditional knowledge and sharing networks may play a less important role in larger Inuit communities.

Does size matter in aged care facilities? A literature review of the relationship between the number of facility beds and quality.

PubMed

Baldwin, Richard; Chenoweth, Lynnette; Dela Rama, Marie; Wang, Alex Y

Theory suggests that structural factors such as aged care facility size (bed numbers) will influence service quality. There have been no recent published studies in support of this theory, and consequently, the available literature has not been useful in assisting decision makers with investment decisions on facility size. The study aimed to address that deficit by reviewing the international literature on the relationships between the size of residential aged care facilities, measured by number of beds, and service quality. A systematic review identified 30 studies that reported a relationship between facility size and quality and provided sufficient details to enable comparison. There are three groups of studies based on measurement of quality-those measuring only resident outcomes, those measuring care and resident outcomes using composite tools, and those focused on regulatory compliance. The overall findings support the posited theory to a large extent, that size is a factor in quality and smaller facilities yield the most favorable results. Studies using multiple indicators of service quality produced more consistent results in favor of smaller facilities, as did most studies of regulatory compliance. The theory that aged care facility size (bed numbers) will influence service quality was supported by 26 of the 30 studies reviewed. The review findings indicate that aged care facility size (number of beds) may be one important factor related to service quality. Smaller facilities are more likely to result in higher quality and better outcomes for residents than larger facilities. This has implications for those who make investment decisions concerning aged care facilities. The findings also raise implications for funders and policy makers to ensure that regulations and policies do not encourage the building of facilities inconsistent with these findings.

Interaction of parenting experiences and brain structure in the prediction of depressive symptoms in adolescents.

PubMed

Yap, Marie B H; Whittle, Sarah; Yücel, Murat; Sheeber, Lisa; Pantelis, Christos; Simmons, Julian G; Allen, Nicholas B

2008-12-01

Although some evidence suggests that neuroanatomic abnormalities may confer risk for major depressive disorder, findings are inconsistent. One potential explanation for this is the moderating role of environmental context, with individuals differing in their biological sensitivity to context. To examine the influence of adverse parenting as an environmental moderator of the association between brain structure and depressive symptoms. Cross-sectional measurement of brain structure, adverse parenting, and depressive symptoms in early adolescents. General community. A total of 106 students aged 11 to 13 years (55 males [51%]), recruited from primary schools in Melbourne, Australia, and their mothers. Selection was based on affective temperament, aimed at producing a sample representing a broad range of risk for major depressive disorder. No participant evidenced current or past case-level depressive, substance use, or eating disorder. (1) Volumetric measures of adolescents' amygdala, hippocampus, and anterior cingulate cortex (ACC); (2) frequency of observed maternal aggressive behavior during a mother-adolescent conflict-resolution interaction; and (3) adolescent depressive symptoms. Boys with smaller right amygdalas reported more depressive symptoms. However, neither hippocampal volume nor asymmetry measures of limbic or paralimbic ACC were directly related to level of depressive symptoms. Importantly, frequency of maternal aggressive behaviors moderated the associations between both the amygdala and ACC, and adolescent symptoms. Particularly, in conditions of low levels of maternal aggressiveness, boys with larger right amygdalas, girls with smaller bilateral amygdalas, and both boys and girls with smaller left paralimbic ACC reported fewer symptoms. These findings help elucidate the complex relationships between brain structure, environmental factors, and depressive symptoms. Further longitudinal research is required to examine how these factors contribute to the onset of case-level disorder, but given that family context risk factors are modifiable, our findings do suggest the potential utility of targeted early parenting interventions.

Commissioning and Validation of the First Monte Carlo Based Dose Calculation Algorithm Commercial Treatment Planning System in Mexico

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

Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A.; Hernandez-Bojorquez, M.

2010-12-07

This work presents the beam data commissioning and dose calculation validation of the first Monte Carlo (MC) based treatment planning system (TPS) installed in Mexico. According to the manufacturer specifications, the beam data commissioning needed for this model includes: several in-air and water profiles, depth dose curves, head-scatter factors and output factors (6x6, 12x12, 18x18, 24x24, 42x42, 60x60, 80x80 and 100x100 mm{sup 2}). Radiographic and radiochromic films, diode and ionization chambers were used for data acquisition. MC dose calculations in a water phantom were used to validate the MC simulations using comparisons with measured data. Gamma index criteria 2%/2 mmmore » were used to evaluate the accuracy of MC calculations. MC calculated data show an excellent agreement for field sizes from 18x18 to 100x100 mm{sup 2}. Gamma analysis shows that in average, 95% and 100% of the data passes the gamma index criteria for these fields, respectively. For smaller fields (12x12 and 6x6 mm{sup 2}) only 92% of the data meet the criteria. Total scatter factors show a good agreement (<2.6%) between MC calculated and measured data, except for the smaller fields (12x12 and 6x6 mm{sup 2}) that show a error of 4.7%. MC dose calculations are accurate and precise for clinical treatment planning up to a field size of 18x18 mm{sup 2}. Special care must be taken for smaller fields.« less

Effect of Thyroid Remnant Volume on the Risk of Hypothyroidism After Hemithyroidectomy: A Prospective Study.

PubMed

Lang, Brian Hung-Hin; Wong, Carlos K H; Wong, Kai Pun; Chu, Kelvin Ka-Wan; Shek, Tony W H

2017-06-01

Hypothyroidism is a common sequel after a hemithyroidectomy. Although various risk factors leading to hypothyroidism have been reported, the effect of the contralateral lobe's volume has been understudied. This study aimed to examine the association between the preoperative contralateral lobe's volume and the risk of postoperative hypothyroidism. During a 2-year period, 150 eligible patients undergoing a hemithyroidectomy were evaluated. The volume of the contralateral nonexcised lobe was estimated preoperatively by independent assessors on ultrasonography using the following formula: width (in cm) × depth (in cm) × length (in cm) × (π/6), adjusted for the body surface area (BSA). Postoperative hypothyroidism was defined as serum thyroid-stimulating hormone (TSH) exceeding 4.78 mIU/L. Any significant characteristics in the univariate analysis were entered into the multivariate analysis to determine independent factors. After a mean follow-up period of 53.5 ± 9.4 months, 44 patients (29.3 %) experienced postoperative hypothyroidism, and 10 of these patients required thyroxine replacement. Hypothyroidism was associated with a higher preoperative TSH level (p < 0.001), a smaller BSA-adjusted volume (p < 0.001), fewer ipsilateral nodules (p = 0.037), and the presence of thyroiditis (p = 0.050). After adjustment for thyroiditis, preoperative TSH (p < 0.001), number of ipsilateral nodules (p = 0.048), and BSA-adjusted volume (p < 0.001) were independent factors for hypothyroidism. Patients with a BSA-adjusted volume smaller than 3.2 ml had a threefold greater hypothyroidism risk than those with a BSA-adjusted volume of 3.2 ml or more (p < 0.001). A significant inverse association between the preoperative contralateral lobe's volume and hypothyroidism risk was observed after hemithyroidectomy. Together with a higher preoperative TSH level and fewer ipsilateral nodules, a smaller BSA-adjusted volume measured by preoperative ultrasonography independently predicted hypothyroidism.

Clinicopathological and Prognostic Analysis of Primary Gastrointestinal Stromal Tumor Presenting with Gastrointestinal Bleeding: a 10-Year Retrospective Study.

PubMed

Yin, Zhijie; Gao, Jinbo; Liu, Weizhen; Huang, Cheng; Shuai, Xiaoming; Wang, Guobin; Tao, Kaixiong; Zhang, Peng

2017-05-01

The objectives of this paper were to investigate the clinicopathological characteristics and prognostic factors of GI-bleeding GIST patients and explore whether GI bleeding is a risk factor for GIST relapse. Primary GIST patients with initial symptoms of GI bleeding or no GI bleeding were retrospectively studied. Up to 178 GI-bleeding GIST patients including 108 (60.7%) males and 70 (39.3%) females were evaluated for the clinicopathological characteristics. The stomach, small bowel, and colorectum were the tumor sites in 82 (46.1%), 85 (47.8%), and 11 (6.2%) patients. Of the 178 patients, 163 GI-bleeding patients had follow-up while another 363 patients from the total population presented without GI bleeding were followed up. Up to 526 patients who received postoperative follow-up were included in the survival analysis. Compared with the 363 non-GI-bleeding patients, GI-bleeding patients developed smaller tumors (P = 0.015) and had a longer relapse-free survival (RFS; P = 0.014). For the 163 GI-bleeding patients, a Cox regression analysis showed that the mitotic count and the platelet-lymphocyte ratio before surgery were independent prognostic predictors for poor outcome regarding RFS. For all 526 patients, a Cox regression analysis indicated that tumor location, mitotic index, platelet-lymphocyte ratio, and GI bleeding were independent prognosis predictors. Compared to non-GI-bleeding GIST patients, patients with GI bleeding were more likely to be male and to have more small intestine GISTs, smaller tumors, and a longer RFS. For GI-bleeding patients, mitotic count and platelet-lymphocyte ratio were independent prognostic indicators. GI bleeding served as a surrogate for smaller GIST and was a protective factor for GIST recurrence.

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

Raghuwanshi, Vikram Singh; Garusinghe, Uthpala Manavi; Ilavsky, Jan

Controlling nanoparticles (NPs) aggregation in cellulose/NPs composites allows to optimise NPs driven properties and their applications. Polyelectrolytes are used to control NPs aggregation and their retention within the fibrous matrix. Here in this study, we aim at evaluating how a polyelectrolyte (Cationic Polyacrylamide; CPAM, molecular weight: 13 MDa, charge: 50%, Radius of gyration: 30–36 nm) adsorbs and re-conforms onto the surface of silica(SiO 2) NPs differing in diameter (8, 22 and 74 nm) and to investigate the respective NPs aggregation in cellulose matrices. SEM shows the local area distribution of NPs in composites. Ultra-SAXS (USAXS) allows to evaluate the averagemore » NPs size distribution and the inter-particle interactions at length scale ranging from 1 to 1000 nm. USAXS data analysis reveals that CPAM covers multiple NPs of the smaller diameter (8 nm), presumably with a single chain to form large size NPs aggregates. As the NPs diameter is increased to 22 nm, CPAM re-conforms over NP surface forming a large shell of thickness 5.5 nm. For the composites with NPs of diameter 74 nm, the CPAM chain re-conforms further onto NP surface and the surrounding shell thickness decreases to 2.2 nm. Lastly, structure factor analysis reveals higher structural ordering for NPs as increases their diameter, which is caused by different conformations adopted by CPAM onto NPs surface.« less

Effect of nanoparticles size and polyelectrolyte on nanoparticles aggregation in a cellulose fibrous matrix

DOE PAGES

Raghuwanshi, Vikram Singh; Garusinghe, Uthpala Manavi; Ilavsky, Jan; ...

2017-09-18

Controlling nanoparticles (NPs) aggregation in cellulose/NPs composites allows to optimise NPs driven properties and their applications. Polyelectrolytes are used to control NPs aggregation and their retention within the fibrous matrix. Here in this study, we aim at evaluating how a polyelectrolyte (Cationic Polyacrylamide; CPAM, molecular weight: 13 MDa, charge: 50%, Radius of gyration: 30–36 nm) adsorbs and re-conforms onto the surface of silica(SiO 2) NPs differing in diameter (8, 22 and 74 nm) and to investigate the respective NPs aggregation in cellulose matrices. SEM shows the local area distribution of NPs in composites. Ultra-SAXS (USAXS) allows to evaluate the averagemore » NPs size distribution and the inter-particle interactions at length scale ranging from 1 to 1000 nm. USAXS data analysis reveals that CPAM covers multiple NPs of the smaller diameter (8 nm), presumably with a single chain to form large size NPs aggregates. As the NPs diameter is increased to 22 nm, CPAM re-conforms over NP surface forming a large shell of thickness 5.5 nm. For the composites with NPs of diameter 74 nm, the CPAM chain re-conforms further onto NP surface and the surrounding shell thickness decreases to 2.2 nm. Lastly, structure factor analysis reveals higher structural ordering for NPs as increases their diameter, which is caused by different conformations adopted by CPAM onto NPs surface.« less

Laterally structured ripple and square phases with one and two dimensional thickness modulations in a model bilayer system.

PubMed

Debnath, Ananya; Thakkar, Foram M; Maiti, Prabal K; Kumaran, V; Ayappa, K G

2014-10-14

Molecular dynamics simulations of bilayers in a surfactant/co-surfactant/water system with explicit solvent molecules show formation of topologically distinct gel phases depending upon the bilayer composition. At low temperatures, the bilayers transform from the tilted gel phase, Lβ', to the one dimensional (1D) rippled, Pβ' phase as the surfactant concentration is increased. More interestingly, we observe a two dimensional (2D) square phase at higher surfactant concentration which, upon heating, transforms to the gel Lβ' phase. The thickness modulations in the 1D rippled and square phases are asymmetric in two surfactant leaflets and the bilayer thickness varies by a factor of ∼2 between maximum and minimum. The 1D ripple consists of a thinner interdigitated region of smaller extent alternating with a thicker non-interdigitated region. The 2D ripple phase is made up of two superimposed square lattices of maximum and minimum thicknesses with molecules of high tilt forming a square lattice translated from the lattice formed with the thickness minima. Using Voronoi diagrams we analyze the intricate interplay between the area-per-head-group, height modulations and chain tilt for the different ripple symmetries. Our simulations indicate that composition plays an important role in controlling the formation of low temperature gel phase symmetries and rippling accommodates the increased area-per-head-group of the surfactant molecules.

Effect of Crack Tip Stress Concentration Factor on Fracture Resistance in Vacuum Environment

DTIC Science & Technology

2015-01-20

indicate: (1) in all alloys, the fracture resistance is highest for blunt-notches (smaller Kt), and is lowest for fatigue -sharpened precracked...paths are transgranular and the fracture mode is ductile void coalescence in all cases, irrespective of the stress concentration factor. 20-01-2015...because of corrosion and/or various loading conditions such as fatigue , fretting, abrasion, etc. Also, the geometry of the structure may cause an

Influence of non-Kolmogorov atmospheric turbulence on the beam quality of vortex beams.

PubMed

Li, Jinhong; Wang, Weiwei; Duan, Meiling; Wei, Jinlin

2016-09-05

Based on the extended Huygens-Fresnel principle and the definition of second-order moments of the Wigner distribution function (WDF), the analytical expressions for the propagation factors (M²-factors) and Strehl ratio S_R of the Gaussian Schell-model (GSM) vortex beams and GSM non-vortex beams propagation through non-Kolmogorov atmospheric turbulence are derived, and used to study the influence of non-Kolmogorov atmospheric turbulence on beam quality of the GSM vortex beams. It is shown that the smaller the generalized structure constant and the outer scale of turbulence are, and the bigger the inner scale of turbulence is, the smaller the normalized propagation factor is, the bigger the Strehl ratio is, and the better the beam quality of GSM vortex beams in atmospheric turbulence is. The variation of beam quality with the generalized exponent α is nonmonotonic, when α = 3.11, the beam quality of the GSM vortex beams is the poorest through non-Kolmogorov atmospheric turbulence. GSM vortex beams is less affected by turbulence than GSM non-vortex beams under certain condition, and will be useful in long-distance free-space optical communications.

The linkage between household water consumption and rainfall in the semi-arid region of East Nusa Tenggara, Indonesia

NASA Astrophysics Data System (ADS)

Messakh, J. J.; Moy, D. L.; Mojo, D.; Maliti, Y.

2018-01-01

Several studies have shown that the amount of water consumption by communities will depend on the factors of water consumption patterns that are influenced by social, cultural, economic and local climate conditions. Research on the linkage between rainfall and household water consumption in semi-arid areas of Indonesia has never been done. This study has been conducted on 17 regions in NTT, and case study has taken samples in one town and one village. The research used survey and documentation method. The results show that the average amount of household water consumption in semi-arid region of East Nusa Tenggara is 107 liters / person / day. Statistical test results using Pearson correlation found r = -0.194 and sig = 0.448. This means that there is a negative correlation between rainfall and household water consumption. The greater the rainfall the smaller the consumption of water, or the smaller the rainfall the greater the consumption of water, but the linkage is not significant. Research shows that the amount of household water consumption will be influenced by many interrelated factors and none of the most dominant factors, including the size of the rainfall that occurs in a region.

HOT-DUST-POOR TYPE 1 ACTIVE GALACTIC NUCLEI IN THE COSMOS SURVEY

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

Hao Heng; Elvis, Martin; Civano, Francesca

2010-11-20

We report a sizable class of type 1 active galactic nuclei (AGNs) with unusually weak near-infrared (1-3 {mu}m) emission in the XMM-COSMOS type 1 AGN sample. The fraction of these 'hot-dust-poor' AGNs increases with redshift from 6% at low redshift (z < 2) to 20% at moderate high redshift (2 < z < 3.5). There is no clear trend of the fraction with other parameters: bolometric luminosity, Eddington ratio, black hole mass, and X-ray luminosity. The 3 {mu}m emission relative to the 1 {mu}m emission is a factor of 2-4 smaller than the typical Elvis et al. AGN spectral energymore » distribution (SED), which indicates a 'torus' covering factor of 2%-29%, a factor of 3-40 smaller than required by unified models. The weak hot dust emission seems to expose an extension of the accretion disk continuum in some of the source SEDs. We estimate the outer edge of their accretion disks to lie at (0.3-2.0) x 10{sup 4} Schwarzschild radii, {approx}10-23 times the gravitational stability radii. Formation scenarios for these sources are discussed.« less

Effect of injection-gas concentration on the electron beam quality from a laser-plasma accelerator

NASA Astrophysics Data System (ADS)

Mirzaie, Mohammad; Zhang, Guobo; Li, Song; Gao, Kai; Li, Guangyu; Ain, Quratul; Hafz, Nasr A. M.

2018-04-01

By using 25-45 TW ultra-short (30 fs) laser pulses, we report on the effect of the injection gas concentration on the quality of electron beams generated by a laser-driven plasma wakefield acceleration employing the ionization-injection. For a plasma formed from helium-nitrogen gas mixture and depending on the concentration of the nitrogen gas, we could distinguish a clear trend for the quality of the generated electron beams in terms of their peak energy, energy-spread, divergence angle, and beam charge. The results clearly showed that the lower the nitrogen concentration, the better the quality (higher peak energy, smaller energy spread, and smaller emittance) of the generated electron beams. The results are in reasonable agreement with two-dimensional particle-in-cell simulations.

Graph theory approach to the eigenvalue problem of large space structures

NASA Technical Reports Server (NTRS)

Reddy, A. S. S. R.; Bainum, P. M.

1981-01-01

Graph theory is used to obtain numerical solutions to eigenvalue problems of large space structures (LSS) characterized by a state vector of large dimensions. The LSS are considered as large, flexible systems requiring both orientation and surface shape control. Graphic interpretation of the determinant of a matrix is employed to reduce a higher dimensional matrix into combinations of smaller dimensional sub-matrices. The reduction is implemented by means of a Boolean equivalent of the original matrices formulated to obtain smaller dimensional equivalents of the original numerical matrix. Computation time becomes less and more accurate solutions are possible. An example is provided in the form of a free-free square plate. Linearized system equations and numerical values of a stiffness matrix are presented, featuring a state vector with 16 components.

Universal behavior of the γ⁎γ→(π0,η,η′) transition form factors

PubMed Central

Melikhov, Dmitri; Stech, Berthold

2012-01-01

The photon transition form factors of π, η and η′ are discussed in view of recent measurements. It is shown that the exact axial anomaly sum rule allows a precise comparison of all three form factors at high-Q2 independent of the different structures and distribution amplitudes of the participating pseudoscalar mesons. We conclude: (i) The πγ form factor reported by Belle is in excellent agreement with the nonstrange I=0 component of the η and η′ form factors obtained from the BaBar measurements. (ii) Within errors, the πγ form factor from Belle is compatible with the asymptotic pQCD behavior, similar to the η and η′ form factors from BaBar. Still, the best fits to the data sets of πγ, ηγ, and η′γ form factors favor a universal small logarithmic rise Q2FPγ(Q2)∼log(Q2). PMID:23226917

The weight and use of schoolbags in New Zealand secondary schools.

PubMed

Whittfield, J K; Legg, S J; Hedderley, D I

2001-07-15

The weight and use of schoolbags amongst 140 students (70 third form students comprising 35 females and 35 males, and 70 sixth form students comprising 35 females and 35 males) from five New Zealand secondary schools was investigated. Third form students, who were smaller in stature and weight than sixth form students, were found to carry 13.2% of their body weight in schoolbags, while sixth form students carried 10.3% of their body weight. Third form students reported carrying their schoolbags for a longer period of time than sixth form students. Third form students also had less access to lockers to store their schoolbooks and supplies as only one of the five schools investigated provided lockers for third form students, whereas four of the five schools provided lockers for sixth form students. Most students used backpacks to transport their supplies, and these were predominantly carried on two shoulders. Heavy schoolbags, long carriage durations and lack of access to lockers amongst third formers, could contribute to the production or maintenance of musculoskeletal symptoms. This study suggests that third form students may be at a higher risk of developing musculoskeletal symptoms than sixth form students.

Method of lining a vertical mine shaft with concrete

DOEpatents

Eklund, James D.; Halter, Joseph M.; Rasmussen, Donald E.; Sullivan, Robert G.; Moffat, Robert B.

1981-01-01

The apparatus includes a cylindrical retainer form spaced inwardly of the wall of the shaft by the desired thickness of the liner to be poured and having overlapping edges which seal against concrete flow but permit the form to be contracted to a smaller circumference after the liner has hardened and is self-supporting. A curb ring extends downwardly and outwardly toward the shaft wall from the bottom of the retainer form to define the bottom surface of each poured liner section. An inflatable toroid forms a seal between the curb ring and the shaft wall. A form support gripper ring having gripper shoes laterally extendable under hydraulic power to engage the shaft wall supports the retainer form, curb ring and liner until the newly poured liner section becomes self-supporting. Adjusting hydraulic cylinders permit the curb ring and retainer form to be properly aligned relative to the form support gripper ring. After a liner section is self-supporting, an advancing system advances the retainer form, curb ring and form support gripper ring toward a shaft boring machine above which the liner is being formed. The advancing system also provides correct horizontal alignment of the form support gripper ring.

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, PAINT OVERSPRAY ARRESTOR, KOCH FILTER CORPORATION, DUO-PAK 650

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than...

40 CFR 60.316 - Test methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Section 60.316 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... for the measurement of VOC concentration. (3) Method 1 for sample and velocity traverses. (4) Method 2... smaller volumes, when necessitated by process variables or other factors, may be approved by the...

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: PAINT OVERSPRAY ARRESTOR, AAF INTERNATIONAL DRI-PAK 40-45%

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) pilot of the Environmental Technology Verification (ETV) Program. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than...

Dependence of Non-Prestonian Behavior of Ceria Slurry with Anionic Surfactant on Abrasive Concentration and Size in Shallow Trench Isolation Chemical Mechanical Polishing

NASA Astrophysics Data System (ADS)

Kang, Hyun‑Goo; Kim, Dae‑Hyeong; Katoh, Takeo; Kim, Sung‑Jun; Paik, Ungyu; Park, Jea‑Gun

2006-05-01

The dependencies of the non-Prestonian behavior of ceria slurry with anionic surfactant on the size and concentration of abrasive particles were investigated by performing chemical mechanical polishing (CMP) experiments using blanket wafers. We found that not only the abrasive size but also the abrasive concentration with surfactant addition influences the non-Prestonian behavior. Such behavior is clearly exhibited with small abrasive sizes and a higher concentrations of abrasives with surfactant addition, because the abrasive particles can locally contact the film surface more effectively with applied pressure. We introduce a factor to quantify these relations with the non-Prestonian behavior of a slurry. For ceria slurry, this non-Prestonian factor, βNP, was determined to be almost independent of the abrasive concentration for a larger size and a smaller weight conentration of abrasive particles, but it increased with the surfactant concentration for a smaller size and a higher concentration of abrasives with surfactant addition.

Basaltic Volcanism and Ancient Planetary Crusts

NASA Technical Reports Server (NTRS)

Shervais, John W.

1993-01-01

The purpose of this project is to decipher the origin of rocks which form the ancient lunar crust. Our goal is to better understand how the moon evolved chemically and, more generally, the processes involved in the chemical fractionation of terrestrial planetoids. This research has implications for other planetary bodies besides the Moon, especially smaller planetoids which evolved early in the history of the solar system and are now thermally stable. The three main areas focused on in our work (lunar mare basalts, KREEP basalts, and plutonic rocks of the lunar highlands) provide complementary information on the lunar interior and the processes that formed it.

Low-order aberration coefficients applied to design of telescopes with freeform surfaces

NASA Astrophysics Data System (ADS)

Stone, Bryan D.; Howard, Joseph M.

2017-09-01

As the number of smallsats and cubesats continues to increase [1], so does the interest in the space optics community to miniaturize reflective optical instrumentation for these smaller platforms. Applications of smallsats are typically for the Earth observing community, but recently opportunities for them are being made available for planetary science, heliophysics and astrophysics concepts [2]. With the smaller satellite platforms come reduced instrument sizes that they accommodate, but the specifications such as field of view and working f/# imposed on the smaller optical systems are often the same, or even more challenging. To meet them, and to "fit in the box", it is necessary to employ additional degrees of freedom to the optical design. An effective strategy to reduce package size is to remove rotational symmetry constraints on the system layout, allowing it to minimize the unused volume by applying rigid body tilts and decenters to mirrors. Requirements for faster systems and wider fields of view can be addressed by allowing optical surfaces to become "freeform" in shape, essentially removing rotational symmetry constraints on the mirrors themselves. This dual approach not only can reduce package size, but also can allow for increased fields of view with improved image quality. Tools were developed in the 1990s to compute low-order coefficients of the imaging properties of asymmetric tilted and decentered systems [3][4]. That approach was then applied to reflective systems with plane symmetry, where the coefficients were used to create closed-form constraints to reduce the number of degrees of freedom of the design space confronting the designer [5][6]. In this paper we describe the geometric interpretation of these coefficients for systems with a plane of symmetry, and discuss some insights that follow for the design of systems without closed-form constraints. We use a common three-mirror design form example to help illustrate these concepts, and incorporate freeform surfaces for each mirror shape. In section II, we evoke the typical form of the wave aberration function taught in most texts on geometrical optics, and then recast it into a general form that no longer assumes rotational symmetry. A freeform surface definition for mirrors is then defined, and the example three-mirror system used throughout this paper is introduced. In section III, the first-order coefficients of the plane symmetric system are discussed, and then the second-order in section IV. In both of these discussions, the example system is perturbed to present the explicit form of the aberration coefficient laid out in section II, and plots are presented using optical design software. Finally, some concluding remarks are given in section V.

Effect of regional grid mix, driving patterns and climate on the comparative carbon footprint of gasoline and plug-in electric vehicles in the United States

NASA Astrophysics Data System (ADS)

Yuksel, Tugce; Tamayao, Mili-Ann M.; Hendrickson, Chris; Azevedo, Inês M. L.; Michalek, Jeremy J.

2016-04-01

We compare life cycle greenhouse gas (GHG) emissions from several light-duty passenger gasoline and plug-in electric vehicles (PEVs) across US counties by accounting for regional differences due to marginal grid mix, ambient temperature, patterns of vehicle miles traveled (VMT), and driving conditions (city versus highway). We find that PEVs can have larger or smaller carbon footprints than gasoline vehicles, depending on these regional factors and the specific vehicle models being compared. The Nissan Leaf battery electric vehicle has a smaller carbon footprint than the most efficient gasoline vehicle (the Toyota Prius) in the urban counties of California, Texas and Florida, whereas the Prius has a smaller carbon footprint in the Midwest and the South. The Leaf is lower emitting than the Mazda 3 conventional gasoline vehicle in most urban counties, but the Mazda 3 is lower emitting in rural Midwest counties. The Chevrolet Volt plug-in hybrid electric vehicle has a larger carbon footprint than the Prius throughout the continental US, though the Volt has a smaller carbon footprint than the Mazda 3 in many urban counties. Regional grid mix, temperature, driving conditions, and vehicle model all have substantial implications for identifying which technology has the lowest carbon footprint, whereas regional patterns of VMT have a much smaller effect. Given the variation in relative GHG implications, it is unlikely that blunt policy instruments that favor specific technology categories can ensure emission reductions universally.

Assessment of gonadal and thyroid histology in Gulf killifish (Fundulus grandis) from Barataria Bay Louisiana one year after the Deepwater Horizon oil spill.

PubMed

Carr, Deborah L; Smith, Ernest E; Thiyagarajah, Arunthavarani; Cromie, Meghan; Crumly, Christopher; Davis, Angela; Dong, Meijun; Garcia, Carlos; Heintzman, Lucas; Hopper, Tiffany; Kouth, Kourtney; Morris, Kimberly; Ruehlen, Amelia; Snodgrass, Phillip; Vaughn, Katelynn; Carr, James A

2018-06-15

We examined gonads and thyroid glands of Gulf killifish (Fundulus grandis) 1yr after the Deepwater Horizon oil spill. F. grandis were trapped from two impacted sites in Barataria Bay (Bayou St. Denis, Bay Jimmy) and an un-impacted site in East Texas (Sabine Pass). The greatest number of F. grandis were collected at Sabine Pass. F. grandis collected at Bayou St. Denis were smaller and had smaller Fulton condition factor scores than fish collected at Sabine Pass. Sex ratios were biased roughly 2:1 in favor of females at Sabine Pass and Bayou St. Denis. Gonad-somatic index (GSI) in males from Sabine Pass was double that of fish from Bay Jimmy while germinal epithelium thickness of the testes was 2.7 fold smaller in males from the impacted site. GSI and oocyte diameters in females from Bayou St. Denis were significantly smaller than females from Bay Jimmy or the reference site. There were no differences in thyroid follicle cell height. While total polyaromatic hydrocarbons at the impacted sites were no different from the reference site, the impacted sites did have greater concentrations of benzo[a]pyrene in sediment pore water. The finding of smaller GSI and testicular germinal epithelium in males from an impacted site suggest that exposure to a combination of oil and dispersants may adversely impact testicular function. Copyright © 2018 Elsevier Inc. All rights reserved.

Transfer of movement sequences: bigger is better.

PubMed

Dean, Noah J; Kovacs, Attila J; Shea, Charles H

2008-02-01

Experiment 1 was conducted to determine if proportional transfer from "small to large" scale movements is as effective as transferring from "large to small." We hypothesize that the learning of larger scale movement will require the participant to learn to manage the generation, storage, and dissipation of forces better than when practicing smaller scale movements. Thus, we predict an advantage for transfer of larger scale movements to smaller scale movements relative to transfer from smaller to larger scale movements. Experiment 2 was conducted to determine if adding a load to a smaller scale movement would enhance later transfer to a larger scale movement sequence. It was hypothesized that the added load would require the participants to consider the dynamics of the movement to a greater extent than without the load. The results replicated earlier findings of effective transfer from large to small movements, but consistent with our hypothesis, transfer was less effective from small to large (Experiment 1). However, when a load was added during acquisition transfer from small to large was enhanced even though the load was removed during the transfer test. These results are consistent with the notion that the transfer asymmetry noted in Experiment 1 was due to factors related to movement dynamics that were enhanced during practice of the larger scale movement sequence, but not during the practice of the smaller scale movement sequence. The findings that the movement structure is unaffected by transfer direction but the movement dynamics are influenced by transfer direction is consistent with hierarchal models of sequence production.

Frost Grape Polysaccharide (FGP), an emulsion-forming arabinogalactan gum from the stems of native North American grape species Vitis riparia Michx

USDA-ARS?s Scientific Manuscript database

A new arabinogalactan is described that is produced in large quantity from the cut stems of the North American grape species Vitis riparia (Frost grape). The sugar composition consists of L-arabinofuranose (L-Araf, 55.2 %) and D-galactopyranose (D-Galp 30.1%), with smaller components of D-xylose (11...

Skylab

NASA Image and Video Library

1971-12-01

The Apollo Telescope Mount (ATM) was designed and constructed at the Marshall Space Flight Center and served as the primary scientific instrument unit aboard Skylab. The ATM consisted of eight scientific instruments as well as a number of smaller experiments. This photograph shows the flight unit solar shield for the ATM that formed the base for the rack, a complex frame, and the canister that contained the instruments.

49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.

Code of Federal Regulations, 2010 CFR

2010-10-01

... breaking away of pieces of the tread or sidewall. Cord means the strands forming the plies in the tire... with a 12-inch or smaller rim diameter, each tire shall have not less than six treadwear indicators... mountain, there must be a six-sided snowflake having a minimum height of one-half the tallest peak...

Make Your School a Bully-Free Zone

ERIC Educational Resources Information Center

Costello, Maureen

2011-01-01

When parents think of bullying at school, the first image that comes to mind may be a large child shoving a smaller, younger child in a schoolyard. But bullying is rarely so obvious these days. The most common forms of bullying can go unnoticed, and can do far more lasting damage. This fact presents a challenge to parents and educators working to…

Corbell PTA's Wild Walk: Fundraiser Cultivates Community

ERIC Educational Resources Information Center

Cassano, Michelle

2012-01-01

When Corbell Elementary opened its doors in 2006 in Frisco, Texas, its newly formed PTA faced the challenge of implementing a productive fundraiser to get the school off to a great start. The new board chose to focus its efforts on a single fundraiser, rather than a series of smaller ones. They wanted to avoid having the children selling any kind…

75 FR 53613 - Notice of Data Availability Supporting Federal Implementation Plans To Reduce Interstate...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-01

... files should avoid the use of special characters, avoid any form of encryption, and be free of any... modeling. This includes both units affected by the Proposed Transport Rule and other EGUs (e.g. fossil-fired units smaller than 25 MWe, non-fossil-fired units, and fossil-fired units 25 MWe or greater in...

Reconstruction and Nation Building Industry. Industry Study, Spring 2009

DTIC Science & Technology

2009-01-01

case of post-conflict operations (recent examples include Iraq, Afghanistan and Lebanon ). Particularly for smaller donors, working through the UN...justice models may have serious defects concerning gender equality, children’s rights, and forms of punishment that are prohibited under international... Lebanon provides an unfortunate example of a failed reconstruction in the 1990’s, which led to violence and a

Nanocrystal synthesis

DOEpatents

Tisdale, William; Prins, Ferry; Weidman, Mark; Beck, Megan

2016-11-01

A method of preparing monodisperse MX semiconductor nanocrystals can include contacting an M-containing precursor with an X donor to form a mixture, where the molar ratio between the M containing precursor and the X donor is large. Alternatively, if additional X donor is added during the reaction, a smaller ratio between the M containing precursor and the X donor can be used to prepare monodisperse MX semiconductor nanocrystals.

7 CFR 1404.6 - Payment to the assignee.

Code of Federal Regulations, 2010 CFR

2010-01-01

... assignee. (a) The assignee shall be paid the smaller of the amount specified on Form CCC-36 or CCC-251 or... indebtedness owed by the assignor to CCC, FSA, or any other agency of the United States shall be subject to offset. (b) Any indebtedness owed by the assignor to CCC or FSA shall be offset from any payment which is...

7 CFR 1404.6 - Payment to the assignee.

Code of Federal Regulations, 2013 CFR

2013-01-01

... assignee. (a) The assignee shall be paid the smaller of the amount specified on Form CCC-36 or CCC-251 or... indebtedness owed by the assignor to CCC, FSA, or any other agency of the United States shall be subject to offset. (b) Any indebtedness owed by the assignor to CCC or FSA shall be offset from any payment which is...

7 CFR 1404.6 - Payment to the assignee.

Code of Federal Regulations, 2012 CFR

2012-01-01

... assignee. (a) The assignee shall be paid the smaller of the amount specified on Form CCC-36 or CCC-251 or... indebtedness owed by the assignor to CCC, FSA, or any other agency of the United States shall be subject to offset. (b) Any indebtedness owed by the assignor to CCC or FSA shall be offset from any payment which is...

7 CFR 1404.6 - Payment to the assignee.

Code of Federal Regulations, 2011 CFR

2011-01-01

... assignee. (a) The assignee shall be paid the smaller of the amount specified on Form CCC-36 or CCC-251 or... indebtedness owed by the assignor to CCC, FSA, or any other agency of the United States shall be subject to offset. (b) Any indebtedness owed by the assignor to CCC or FSA shall be offset from any payment which is...

7 CFR 1404.6 - Payment to the assignee.

Code of Federal Regulations, 2014 CFR

2014-01-01

... assignee. (a) The assignee shall be paid the smaller of the amount specified on Form CCC-36 or CCC-251 or... indebtedness owed by the assignor to CCC, FSA, or any other agency of the United States shall be subject to offset. (b) Any indebtedness owed by the assignor to CCC or FSA shall be offset from any payment which is...

Amino acid sequence of the smaller basic protein from rat brain myelin

PubMed Central

Dunkley, Peter R.; Carnegie, Patrick R.

1974-01-01

1. The complete amino acid sequence of the smaller basic protein from rat brain myelin was determined. This protein differs from myelin basic proteins of other species in having a deletion of a polypeptide of 40 amino acid residues from the centre of the molecule. 2. A detailed comparison is made of the constant and variable regions in a group of myelin basic proteins from six species. 3. An arginine residue in the rat protein was found to be partially methylated. The ratio of methylated to unmethylated arginine at this position differed from that found for the human basic protein. 4. Three tryptic peptides were isolated in more than one form. The differences between the two forms of each peptide are discussed in relation to the electrophoretic heterogeneity of myelin basic proteins, which is known to occur at alkaline pH values. 5. Detailed evidence for the amino acid sequence of the protein has been deposited as Supplementary Publication SUP 50029 at the British Library (Lending Division) (formerly the National Lending Library for Science and Technology), Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies may be obtained on the terms given in Biochem. J. (1973) 131, 5. PMID:4141893

Future directions in research on institutional and interpersonal discrimination and children's health.

PubMed

Acevedo-Garcia, Dolores; Rosenfeld, Lindsay E; Hardy, Erin; McArdle, Nancy; Osypuk, Theresa L

2013-10-01

Research evidence indicates that 2 forms of racial discrimination-perceived interpersonal discrimination and racial/ethnic residential segregation (a form of institutional discrimination)-may influence children's health and disparities. Although research on these 2 forms of discrimination and health has primarily focused on adults, smaller bodies of work have documented that perceived interpersonal discrimination and segregation have a negative effect on infants' health, and that perceived interpersonal discrimination may negatively affect children's mental health. Three directions for research are (1) incorporating a life-course perspective into studies of discrimination and children's health, (2) linking residential segregation with geography-of-opportunity conceptual frameworks and measures, and (3) considering residential segregation along with segregation in other contexts that influence children's health (e.g., schools).

Image simulation for electron energy loss spectroscopy

DOE PAGES

Oxley, Mark P.; Pennycook, Stephen J.

2007-10-22

In this paper, aberration correction of the probe forming optics of the scanning transmission electron microscope has allowed the probe-forming aperture to be increased in size, resulting in probes of the order of 1 Å in diameter. The next generation of correctors promise even smaller probes. Improved spectrometer optics also offers the possibility of larger electron energy loss spectrometry detectors. The localization of images based on core-loss electron energy loss spectroscopy is examined as function of both probe-forming aperture and detector size. The effective ionization is nonlocal in nature, and two common local approximations are compared to full nonlocal calculations.more » Finally, the affect of the channelling of the electron probe within the sample is also discussed.« less

Digital color representation

DOEpatents

White, James M.; Faber, Vance; Saltzman, Jeffrey S.

1992-01-01

An image population having a large number of attributes is processed to form a display population with a predetermined smaller number of attributes which represent the larger number of attributes. In a particular application, the color values in an image are compressed for storage in a discrete lookup table (LUT) where an 8-bit data signal is enabled to form a display of 24-bit color values. The LUT is formed in a sampling and averaging process from the image color values with no requirement to define discrete Voronoi regions for color compression. Image color values are assigned 8-bit pointers to their closest LUT value whereby data processing requires only the 8-bit pointer value to provide 24-bit color values from the LUT.

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

Fan, Jiwen; Rosenfeld, Daniel; Zhang, Yuwei

Aerosol-cloud interactions remain the largest uncertainty in climate projections. Ultrafine aerosol particles smaller than 50 nanometers (UAP <50) can be abundant in the troposphere, but are conventionally considered too small to affect cloud formation. However, observational evidence and numerical simulations of deep convective clouds (DCCs) over the Amazon show that DCCs forming in a low aerosol environment can develop very large vapor supersaturation because fast droplet coalescence reduces integrated droplet surface area and subsequent condensation. UAP <50 from pollution plumes that are ingested into such clouds can be activated to form additional cloud droplets on which excess supersaturation condenses andmore » forms additional cloud water and latent heating, thus intensifying convective strength. This mechanism suggests a strong anthropogenic invigoration of DCCs in previously pristine regions of the world.« less

Wake-Vortex Separation Distances when Flight-Path Corridors are Constrained

NASA Technical Reports Server (NTRS)

Rossow, Vernon J.; Olson, Lawrence E. (Technical Monitor)

1995-01-01

Since the vortex wakes of large transport aircraft can pose a hazard to smaller following aircraft during landing and takeoff operations, certain separation guidelines are followed while aircraft are in the approach and departure corridors at airports. These guidelines reduce the capacity of airports because the separation distances are larger than other airport factors require. This paper studies the effect that a decrease in the size of the cross-section of the flight corridors for air traffic control would have on the wake-vortex separation guidelines; e.g., when the Global Positioning System (GPS) is implemented for air traffic control. It is first shown why smaller flight corridors permit reduced spacings at airports. Several arrangements of smaller flight corridors are then presented to illustrate how differing atmospheric and airport conditions can be accommodated. These considerations indicate that a reduction is then permissible in the wake-vortex spacings while still retaining the same or an improved degree of safety.

The nanocomposite nature of bone drives its strength and damage resistance

NASA Astrophysics Data System (ADS)

Tertuliano, Ottman A.; Greer, Julia R.

2016-11-01

In human bone, an amorphous mineral serves as a precursor to the formation of a highly substituted nanocrystalline apatite. However, the precise role of this amorphous mineral remains unknown. Here, we show by using transmission electron microscopy that 100-300 nm amorphous calcium phosphate regions are present in the disordered phase of trabecular bone. Nanomechanical experiments on cylindrical samples, with diameters between 250 nm and 3,000 nm, of the bone's ordered and disordered phases revealed a transition from plastic deformation to brittle failure and at least a factor-of-2 higher strength in the smaller samples. We postulate that this transition in failure mechanism is caused by the suppression of extrafibrillar shearing in the smaller samples, and that the emergent smaller-is-stronger size effect is related to the sample-size scaling of the distribution of flaws. Our findings should help in the understanding of the multi-scale nature of bone and provide insights into the biomineralization process.

Reproductive motivation and family-size preferences among Nigerian men.

PubMed

Isiugo-Abanihe, U C

1994-01-01

Data collected from 3,073 couples in four Nigerian cities and one semi-urban settlement were used to examine reproductive decision-making and male motivation for large family size. The report concludes that the characteristic male-dominant and patrilineal traditions support large family size and that men's reproductive motivation, to a large extent, affects the reproductive behavior of their wives. Therefore, the factors influencing men's reproductive outcomes and intentions are considered important for fertility transition in Nigeria. Male education, age at marriage, monogamy, interspousal communication, and intention not to rely on children for old-age support are significantly related to smaller actual family size and preferences for smaller families, while being in a male-dominant family setting has a strong relation with large family size and preferences for larger families. The policy implication of this study is the need for programs targeted at men and designed to change their attitudes about population matters and motivate them, and hence their wives, to produce smaller families.

Identification of a novel C1q family member in color crucian carp (Carassius auratus) ovary.

PubMed

Chen, Bo; Gui, Jianfang

2004-07-01

Potential roles of C1q/tumor necrosis factor (TNF) superfamily proteins have been observed in vertebrate oogenesis and oocyte maturation, but no ovary-specific member has been identified so far. In this study, we have cloned and identified a novel member of C1q family with a C1q domain in the C-terminal from fully grown oocyte cDNA library of color crucian carp and demonstrated that the gene might be specifically expressed in ovary and therefore designated as Carassius auratus ovary-specific C1q-like factor, CaOC1q-like factor. It encodes a 213 amino acid protein with a 17 amino acid signal peptide. There is only one protein band of about 24.5 kDa in the extracts from phase I to phase IV oocytes, but two positive protein bands are detected in the extracts of mature eggs and fertilized eggs. Furthermore, the mobility shift of the smaller target protein band cannot be eliminated by phosphatase treatment, but the larger protein band increases its mobility on the gel after phosphatase treatment, suggesting that the larger protein might be a phosphorylated form. Immunofluorescence localization indicates that the CaOC1q-like proteins localize in cytoplasm, cytoplasm membrane and egg envelope of the oocytes at cortical granule stage and vitellogenesis stage, whereas they were compressed to cytoplasm margin in ovulated mature eggs and discharged into perivitelline space between cytoplasm membrane and egg envelope after egg fertilization. Further studies on distribution and translocation mechanism of the CaOC1q-like factor will be benefit to elucidate the unique function in oogenesis, oocyte maturation and egg fertilization.

Swallowing Disorders in Sjögren's Syndrome: Prevalence, Risk Factors, and Effects on Quality of Life.

PubMed

Pierce, Jenny L; Tanner, Kristine; Merrill, Ray M; Miller, Karla L; Kendall, Katherine A; Roy, Nelson

2016-02-01

This epidemiological investigation examined the prevalence, risk factors, and quality-of-life effects of swallowing disorders in Sjögren's syndrome (SS). One hundred and one individuals with primary or secondary SS (94 females, 7 males; mean age 59.4, SD = 14.1) were interviewed regarding the presence, nature, and impact of swallowing disorders and symptoms. Associations among swallowing disorders and symptoms, select medical and social history factors, SS disease severity, and the M.D. Anderson Dysphagia Inventory (MDADI) and Short Form 36 Health Survey (SF-36) were examined. The prevalence of a current self-reported swallowing disorder was 64.4 %. SS disease severity was the strongest predictor of swallowing disorders, including significant associations with the following swallow symptoms: taking smaller bites, thick mucus in the throat, difficulty placing food in the mouth, and wheezing while eating (p < .05). Additional swallowing disorder risk factors included the presence of a self-reported voice disorder, esophageal reflux, current exposure to secondary tobacco smoke, frequent neck or throat tension, frequent throat clearing, chronic post-nasal drip, and stomach or duodenal ulcers. Swallowing disorders did not differ on the basis of primary or secondary SS. Swallowing disorders and specific swallowing symptoms were uniquely associated with reduced quality of life. Among those with swallowing disorders, 42 % sought treatment, with approximately half reporting improvement. Patient-perceived swallowing disorders are relatively common in SS and increase with disease severity. Specific swallowing symptoms uniquely and significantly reduce swallow and health-related quality of life, indicating the need for increased identification and management of dysphagia in this population.

Rocky Mountain spotted fever in Georgia, 1961-75: analysis of social and environmental factors affecting occurrence.

PubMed Central

Newhouse, V F; Choi, K; Holman, R C; Thacker, S B; D'Angelo, L J; Smith, J D

1986-01-01

For the period of 1961 through 1975, 10 geographic and sociologic variables in each of the 159 counties of Georgia were analyzed to determine how they were correlated with the occurrence of Rocky Mountain spotted fever (RMSF). Combinations of variables were transformed into a smaller number of factors using principal-component analysis. Based upon the relative values of these factors, geographic areas of similarity were delineated by cluster analysis. It was found by use of these analyses that the counties of the State formed four similarity clusters, which we called south, central, lower north and upper north. When the incidence of RMSF was subsequently calculated for each of these regions of similarity, the regions had differing RMSF incidence; low in the south and upper north, moderate in the central, and high in the lower north. The four similarity clusters agreed closely with the incidence of RMSF when both were plotted on a map. Thus, when analyzed simultaneously, the 10 variables selected could be used to predict the occurrence of RMSF. The most important variables were those of climate and geography. Of secondary, but still major importance, were the changes over the 15-year period in variables associated with humans and their environmental alterations. Detailed examination of these factors has permitted quantitative evaluation of the simultaneous impacts of the geographic and sociologic variables on the occurrence of RMSF in Georgia. These analyses could be updated to reflect changes in the relevant variables and tested as a means of identifying new high risk areas for RMSF in the State. More generally, this method might be adapted to clarify our understanding of the relative importance of individual variables in the ecology of other diseases or environmental health problems. PMID:3090609

ON HIGHLY CLUMPED MAGNETIC WIND MODELS FOR COOL EVOLVED STARS

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

Harper, G. M.

2010-09-10

Recently, it has been proposed that the winds of non-pulsating and non-dusty K and M giants and supergiants may be driven by some form of magnetic pressure acting on highly clumped wind material. While many researchers believe that magnetic processes are responsible for cool evolved stellar winds, existing MHD and Alfven wave-driven wind models have magnetic fields that are essentially radial and tied to the photosphere. The clumped magnetic wind scenario is quite different in that the magnetic flux is also being carried away from the star with the wind. We test this clumped wind hypothesis by computing continuum radiomore » fluxes from the {zeta} Aur semiempirical model of Baade et al., which is based on wind-scattered line profiles. The radio continuum opacity is proportional to the electron density squared, while the line scattering opacity is proportional to the gas density. This difference in proportionality provides a test for the presence of large clumping factors. We derive the radial distribution of clump factors (CFs) for {zeta} Aur by comparing the nonthermal pressures required to produce the semiempirical velocity distribution with the expected thermal pressures. The CFs are {approx}5 throughout the sub-sonic inner wind region and then decline outward. These implied clumping factors lead to excess radio emission at 2.0 cm, while at 6.2 cm it improves agreement with the smooth unclumped model. Smaller clumping factors of {approx}2 lead to better overall agreement but also increase the discrepancy at 2 cm. These results do not support the magnetic clumped wind hypothesis and instead suggest that inherent uncertainties in the underlying semiempirical model probably dominate uncertainties in predicted radio fluxes. However, new ultraviolet line and radio continuum observations are needed to test the new generations of inhomogeneous magnetohydrodynamic wind models.« less

Analysis of nucleon electromagnetic form factors from light-front holographic QCD: The spacelike region

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

Sufian, Raza Sabbir; de Teramond, Guy F.; Brodsky, Stanley J.

We present a comprehensive analysis of the space-like nucleon electromagnetic form factors and their flavor decomposition within the framework of light-front holographic QCD. We show that the inclusion of the higher Fock componentsmore » $$|{qqqq\\bar{q}}$$ has a significant effect on the spin-flip elastic Pauli form factor and almost zero effect on the spin-conserving Dirac form factor. We present light-front holographic QCD results for the proton and neutron form factors at any momentum transfer range, including asymptotic predictions, and show that our results agree with the available experimental data with high accuracy. In order to correctly describe the Pauli form factor we need an admixture of a five quark state of about 30$$\\%$$ in the proton and about 40$$\\%$$ in the neutron. We also extract the nucleon charge and magnetic radii and perform a flavor decomposition of the nucleon electromagnetic form factors. The free parameters needed to describe the experimental nucleon form factors are very few: two parameters for the probabilities of higher Fock states for the spin-flip form factor and a phenomenological parameter $r$, required to account for possible SU(6) spin-flavor symmetry breaking effects in the neutron, whereas the Pauli form factors are normalized to the experimental values of the anomalous magnetic moments. As a result, the covariant spin structure for the Dirac and Pauli nucleon form factors prescribed by AdS$$_5$$ semiclassical gravity incorporates the correct twist scaling behavior from hard scattering and also leads to vector dominance at low energy.« less

Analysis of nucleon electromagnetic form factors from light-front holographic QCD: The spacelike region

DOE PAGES

Sufian, Raza Sabbir; de Teramond, Guy F.; Brodsky, Stanley J.; ...

2017-01-10

We present a comprehensive analysis of the space-like nucleon electromagnetic form factors and their flavor decomposition within the framework of light-front holographic QCD. We show that the inclusion of the higher Fock componentsmore » $$|{qqqq\\bar{q}}$$ has a significant effect on the spin-flip elastic Pauli form factor and almost zero effect on the spin-conserving Dirac form factor. We present light-front holographic QCD results for the proton and neutron form factors at any momentum transfer range, including asymptotic predictions, and show that our results agree with the available experimental data with high accuracy. In order to correctly describe the Pauli form factor we need an admixture of a five quark state of about 30$$\\%$$ in the proton and about 40$$\\%$$ in the neutron. We also extract the nucleon charge and magnetic radii and perform a flavor decomposition of the nucleon electromagnetic form factors. The free parameters needed to describe the experimental nucleon form factors are very few: two parameters for the probabilities of higher Fock states for the spin-flip form factor and a phenomenological parameter $r$, required to account for possible SU(6) spin-flavor symmetry breaking effects in the neutron, whereas the Pauli form factors are normalized to the experimental values of the anomalous magnetic moments. As a result, the covariant spin structure for the Dirac and Pauli nucleon form factors prescribed by AdS$$_5$$ semiclassical gravity incorporates the correct twist scaling behavior from hard scattering and also leads to vector dominance at low energy.« less

Tidal Amplitude for a Self-gravitating, Compressible Sphere

NASA Astrophysics Data System (ADS)

Hurford, T. A.; Greenberg, R.

2001-11-01

Most modern evaluations of tidal amplitude derive from the approach presented by Love [1]. Love's analysis for a homogeneous sphere assumed an incompressible material, which required introduction of a non-rigorously justified pressure term. We solve the more general case of arbitrary compressibility, which allows for a more straightforward derivation. We find the h2 love number of a body of radius R, density ρ , and surface gravity g to be h2 = \\Bigg[\\frac{{5}/{2}}{1+\\frac{19 \\mu}{2 \\rho g R}}\\Bigg] \\Bigg\\{ \\frac{2 \\rho g R (35+28\\frac{\\mu}{\\lambda}) + 19 \\mu (35+28\\frac{\\mu}{\\lambda})} {2 \\rho g R (35+31\\frac{\\mu}{\\lambda}) + 19 \\mu (35+{490}/{19}\\frac{\\mu}{\\lambda})}\\Bigg\\} λ the Lamé constant. This h2 is the product of Love's expression for h2 (in square brackets) and a ``compressibility-correction'' factor (in \\{\\} brackets). Unlike Love's expression, this result is valid for any degree of compressibility (i.e. any λ ). For the incompressible case (λ -> ∞ ) the correction factor approaches 1, so that h2 matches the classical form given by Love. In reality, of course, materials are not incompressible and the difference between our solution and Love's is significant. Assuming that the elastic terms dominate over the gravitational contribution (i.e. 19 μ /(2 ρ g R) >> 1), our solution can be ~ 7% percent larger than Love's solution for large μ /λ . If the gravity dominates (i.e. 19 μ /(2 ρ g R) << 1), our solution is ~ 10 % smaller than Love's solution for large μ /λ . For example, a rocky body (μ /λ ~ 1 [2]), Earth-sized (19μ /(2 ρ g R) ~ 1) body, h2 would be reduced by about 1% from the classical formula. Similarly, under some circumstances the l2 Love number for a uniform sphere could be 22% smaller than Love's evaluation. [1] Love, A.E.H., A Treatise on the Mathematical Theory of Elasticity, New York Dover Publications, 1944 [2] Kaula, W.M., An Introduction to Planetary Physics: The Terrestrial Planets, John Wiley & Sons, Inc., 1968

Analysis of various factors affecting pupil size in patients with glaucoma.

PubMed

Park, Ji Woong; Kang, Bong Hui; Kwon, Ji Won; Cho, Kyong Jin

2017-09-16

Pupil size is an important factor in predicting post-operative satisfaction. We assessed the correlation between pupil size, measured by Humphrey static perimetry, and various affecting factors in patients with glaucoma. In total, 825 eyes of 415 patients were evaluated retrospectively. Pupil size was measured with Humphrey static perimetry. Comparisons of pupil size according to the presence of glaucoma were evaluated, as were correlations between pupil size and various factors, including age, logMAR best corrected visual acuity (BCVA), retinal nerve fiber layer (RNFL) thickness, spherical equivalent, intraocular pressure, axial length, central corneal thickness, white-to-white, and the kappa angle. Pupil size was significantly smaller in glaucoma patients than in glaucoma suspects (p < 0.001) or the normal group (p < 0.001). Pupil size decreased significantly as age (p < 0.001) and central cornea thickness (p = 0.007) increased, and increased significantly as logMAR BCVA (p = 0.02) became worse and spherical equivalent (p = 0.007) and RNFL thickness (p = 0.042) increased. In patients older than 50 years, pupil size was significantly larger in eyes with a history of cataract surgery. Humphrey static perimetry can be useful in measuring pupil size. Pupil size was significantly smaller in eyes with glaucoma. Other factors affecting pupil size can be used in a preoperative evaluation when considering cataract surgery or laser refractive surgery.

Geographic variation in patterns of nestedness among local stream fish assemblages in Virginia

USGS Publications Warehouse

Cook, R.R.; Angermeier, P.L.; Finn, D.S.; Poff, N.L.; Krueger, K.L.

2004-01-01

Nestedness of faunal assemblages is a multiscale phenomenon, potentially influenced by a variety of factors. Prior small-scale studies have found freshwater fish species assemblages to be nested along stream courses as a result of either selective colonization or extinction. However, within-stream gradients in temperature and other factors are correlated with the distributions of many fish species and may also contribute to nestedness. At a regional level, strongly nested patterns would require a consistent set of structuring mechanisms across streams, and correlation among species' tolerances of the environmental factors that influence distribution. Thus, nestedness should be negatively associated with the spatial extent of the region analyzed and positively associated with elevational gradients (a correlate of temperature and other environmental factors). We examined these relationships for the freshwater fishes of Virginia. Regions were defined within a spatial hierarchy and included whole river drainages, portions of drainages within physiographic provinces, and smaller subdrainages. In most cases, nestedness was significantly stronger in regions of smaller spatial extent and in regions characterized by greater topographic relief. Analysis of hydrologic variability and patterns of faunal turnover provided no evidence that interannual colonization/extinction dynamics contributed to elevational differences in nestedness. These results suggest that, at regional scales, nestedness is influenced by interactions between biotic and abiotic factors, and that the strongest nestedness is likely to occur where a small number of organizational processes predominate, i.e., over small spatial extents and regions exhibiting strong environmental gradients. ?? Springer-Verlag 2004.

Analysis of occlusal variables, dental attrition, and age for distinguishing healthy controls from female patients with intracapsular temporomandibular disorders.

PubMed

Seligman, D A; Pullinger, A G

2000-01-01

Confusion about the relationship of occlusion to temporomandibular disorders (TMD) persists. This study attempted to identify occlusal and attrition factors plus age that would characterize asymptomatic normal female subjects. A total of 124 female patients with intracapsular TMD were compared with 47 asymptomatic female controls for associations to 9 occlusal factors, 3 attrition severity measures, and age using classification tree, multiple stepwise logistic regression, and univariate analyses. Models were tested for accuracy (sensitivity and specificity) and total contribution to the variance. The classification tree model had 4 terminal nodes that used only anterior attrition and age. "Normals" were mainly characterized by low attrition levels, whereas patients had higher attrition and tended to be younger. The tree model was only moderately useful (sensitivity 63%, specificity 94%) in predicting normals. The logistic regression model incorporated unilateral posterior crossbite and mediotrusive attrition severity in addition to the 2 factors in the tree, but was slightly less accurate than the tree (sensitivity 51%, specificity 90%). When only occlusal factors were considered in the analysis, normals were additionally characterized by a lack of anterior open bite, smaller overjet, and smaller RCP-ICP slides. The log likelihood accounted for was similar for both the tree (pseudo R(2) = 29.38%; mean deviance = 0.95) and the multiple logistic regression (Cox Snell R(2) = 30.3%, mean deviance = 0.84) models. The occlusal and attrition factors studied were only moderately useful in differentiating normals from TMD patients.

SETI and SEH (Statistical Equation for Habitables)

NASA Astrophysics Data System (ADS)

Maccone, Claudio

2011-01-01

The statistics of habitable planets may be based on a set of ten (and possibly more) astrobiological requirements first pointed out by Stephen H. Dole in his book "Habitable planets for man" (1964). In this paper, we first provide the statistical generalization of the original and by now too simplistic Dole equation. In other words, a product of ten positive numbers is now turned into the product of ten positive random variables. This we call the SEH, an acronym standing for "Statistical Equation for Habitables". The mathematical structure of the SEH is then derived. The proof is based on the central limit theorem (CLT) of Statistics. In loose terms, the CLT states that the sum of any number of independent random variables, each of which may be arbitrarily distributed, approaches a Gaussian (i.e. normal) random variable. This is called the Lyapunov form of the CLT, or the Lindeberg form of the CLT, depending on the mathematical constraints assumed on the third moments of the various probability distributions. In conclusion, we show that The new random variable NHab, yielding the number of habitables (i.e. habitable planets) in the Galaxy, follows the lognormal distribution. By construction, the mean value of this lognormal distribution is the total number of habitable planets as given by the statistical Dole equation. But now we also derive the standard deviation, the mode, the median and all the moments of this new lognormal NHab random variable. The ten (or more) astrobiological factors are now positive random variables. The probability distribution of each random variable may be arbitrary. The CLT in the so-called Lyapunov or Lindeberg forms (that both do not assume the factors to be identically distributed) allows for that. In other words, the CLT "translates" into our SEH by allowing an arbitrary probability distribution for each factor. This is both astrobiologically realistic and useful for any further investigations. An application of our SEH then follows. The (average) distancebetween any two nearby habitable planets in the Galaxy may be shown to be inversely proportional to the cubic root of NHab. Then, in our approach, this distance becomes a new random variable. We derive the relevant probability density function, apparently previously unknown and dubbed "Maccone distribution" by Paul Davies in 2008. Data Enrichment Principle. It should be noticed that ANY positive number of random variables in the SEH is compatible with the CLT. So, our generalization allows for many more factors to be added in the future as long as more refined scientific knowledge about each factor will be known to the scientists. This capability to make room for more future factors in the SEH we call the "Data Enrichment Principle", and we regard it as the key to more profound future results in the fields of Astrobiology and SETI. A practical example is then given of how our SEH works numerically. We work out in detail the case where each of the ten random variables is uniformly distributed around its own mean value as given by Dole back in 1964 and has an assumed standard deviation of 10%. The conclusion is that the average number of habitable planets in the Galaxy should be around 100 million±200 million, and the average distance in between any couple of nearby habitable planets should be about 88 light years±40 light years. Finally, we match our SEH results against the results of the Statistical Drake Equation that we introduced in our 2008 IAC presentation. As expected, the number of currently communicating ET civilizations in the Galaxy turns out to be much smaller than the number of habitable planets (about 10,000 against 100 million, i.e. one ET civilization out of 10,000 habitable planets). And the average distance between any two nearby habitable planets turns out to be much smaller than the average distance between any two neighboring ET civilizations: 88 light years vs. 2000 light years, respectively. This means an ET average distance about 20 times higher than the average distance between any couple of adjacent habitable planets.

Behavioral inhibition in childhood predicts smaller hippocampal volume in adolescent offspring of parents with panic disorder.

PubMed

Schwartz, C E; Kunwar, P S; Hirshfeld-Becker, D R; Henin, A; Vangel, M G; Rauch, S L; Biederman, J; Rosenbaum, J F

2015-07-21

Behavioral inhibition (BI) is a genetically influenced behavioral profile seen in 15-20% of 2-year-old children. Children with BI are timid with people, objects and situations that are novel or unfamiliar, and are more reactive physiologically to these challenges as evidenced by higher heart rate, pupillary dilation, vocal cord tension and higher levels of cortisol. BI predisposes to the later development of anxiety, depression and substance abuse. Reduced hippocampal volumes have been observed in anxiety disorders, depression and posttraumatic stress disorder. Animal models have demonstrated that chronic stress can damage the hippocampal formation and implicated cortisol in these effects. We, therefore, hypothesized that the hippocampi of late adolescents who had been behaviorally inhibited as children would be smaller compared with those who had not been inhibited. Hippocampal volume was measured with high-resolution structural magnetic resonance imaging in 43 females and 40 males at 17 years of age who were determined to be BI+ or BI- based on behaviors observed in the laboratory as young children. BI in childhood predicted reduced hippocampal volumes in the adolescents who were offspring of parents with panic disorder, or panic disorder with comorbid major depression. We discuss genetic and environmental factors emanating from both child and parent that may explain these findings. To the best of our knowledge, this is the first study to demonstrate a relationship between the most extensively studied form of temperamentally based human trait anxiety, BI, and hippocampal structure. The reduction in hippocampal volume, as reported by us, suggests a role for the hippocampus in human trait anxiety and anxiety disorder that warrants further investigation.

The effects of isolation on the demography and genetic diversity of long-lived species: Implications for conservation and management of the gopher tortoise (Gopherus polyphemus)

USGS Publications Warehouse

Ennen, J.R.; Birkhead, R.D.; Kreiser, B.R.; Gaillard, D.L.; Qualls, C.P.; Lovich, J.E.

2011-01-01

In the southeastern United States, habitat loss has fragmented the landscape and isolated many populations of this region's flora and fauna, which has presumably resulted in smaller population sizes and reduced levels of genetic diversity. For example, forestry practices and anthropogenic disturbances are both cited as factors fragmenting the once extensive range of Gopherus polyphemus. One localized, but extreme, source of fragmentation was the impoundment of the Chattahoochee River in 1963 to form Walter F. George Reservoir along the border of Georgia and Alabama. The formation of this reservoir isolated populations of G. polyphemus on two newly created islands providing a natural laboratory to explore the demographics and genetic effects of fragmentation on a long-lived species. These populations were first surveyed in 1984 and, 21 years later, we revisited them to collect demographic data and tissue samples for genetic analysis. We genotyped all individuals for 10 microsatellite loci, and we tested these data for bottlenecks and compared them to levels of genetic diversity for populations from other portions of the range. We found 45 and two individuals on the larger and smaller islands, respectively. On the large island, however, the population size was identical to the 1984 survey. Only the population structure based on estimated age differed between the 1984 and 2004 surveys, while population size structure based on carapace length, sex ratio, and sex-specific growth rates did not differ. The population of the large island showed genetic evidence of a past bottleneck. The genetic diversity indices from the population of the large island, however, were comparable to or greater than those found at mainland sites, in particular from western populations.

Blackbody infrared radiative dissociation of protonated oligosaccharides.

PubMed

Fentabil, Messele A; Daneshfar, Rambod; Kitova, Elena N; Klassen, John S

2011-12-01

The dissociation pathways, kinetics, and energetics of protonated oligosaccharides in the gas phase were investigated using blackbody infrared radiative dissociation (BIRD). Time-resolved BIRD measurements were performed on singly protonated ions of cellohexaose (Cel(6)), which is composed of β-(1→4)-linked glucopyranose rings, and five malto-oligosaccharides (Mal(x), where x=4-8), which are composed of α-(1→4)-linked glucopyranose units. At the temperatures investigated (85-160 °C), the oligosaccharides dissociate at the glycosidic linkages or by the loss of a water molecule to produce B- or Y-type ions. The Y ions dissociate to smaller Y or B ions, while the B ions yield exclusively smaller B ions. The sequential loss of water molecules from the smallest B ions (B(1) and B(2)) also occurs. Rate constants for dissociation of the protonated oligosaccharides and the corresponding Arrhenius activation parameters (E(a) and A) were determined. The E(a) and A-factors measured for protonated Mal(x) (x>4) are indistinguishable within error (~19 kcal mol(-1), 10(10) s(-1)), which is consistent with the ions being in the rapid energy exchange limit. In contrast, the Arrhenius parameters for protonated Cel(6) (24 kcal mol(-1), 10(12) s(-1)) are significantly larger. These results indicate that both the energy and entropy changes associated with the glycosidic bond cleavage are sensitive to the anomeric configuration. Based on the results of this study, it is proposed that formation of B and Y ions occurs through a common dissociation mechanism, with the position of the proton establishing whether a B or Y ion is formed upon glycosidic bond cleavage. © American Society for Mass Spectrometry, 2011

A mechanistic assessment of seasonal microhabitat selection by drift-feeding rainbow trout Oncorhynchus mykiss in a southwestern headwater stream

USGS Publications Warehouse

Kalb, Bradley W.; Huntsman, Brock M.; Caldwell, Colleen A.; Bozek, Michael A.

2018-01-01

The positioning of fishes within a riverscape is dependent on the proximity of complementary habitats. In this study, foraging and non-foraging habitat were quantified monthly over an entire year for a rainbow trout (Oncorhynchus mykiss) population in an isolated, headwater stream in southcentral New Mexico. The stream follows a seasonal thermal and hydrologic pattern typical for a Southwestern stream and was deemed suitable for re-introduction of the native and close relative, Rio Grande cutthroat trout (O. clarkii virginalis). However, uncertainty associated with limited habitat needed to be resolved if repatriation of the native fish was to be successful. Habitat was evaluated using resource selection functions with a mechanistic drift-foraging model to explain trout distributions. Macroinvertebrate drift was strongly season- and temperature-dependent (lower in winter and spring, higher in summer and fall). Models identified stream depth as the most limiting factor for habitat selection across seasons and size-classes. Additionally, positions closer to cover were selected during the winter by smaller size-classes (0, 1, 2), while net energy intake was important during the spring for most size-classes (0, 1, 2, 3). Drift-foraging models identified that 81% of observed trout selected positions that could meet maintenance levels throughout the year. Moreover, 40% of selected habitats could sustain maximum growth. Stream positions occupied by rainbow trout were more energetically profitable than random sites regardless of season or size-class. Larger size-classes (3, 4+) were energetically more limited throughout the year than were smaller size-classes. This research suggests that habitat in the form of deep pools is of paramount importance for rainbow trout or native cutthroat trout.

Multi-camera synchronization core implemented on USB3 based FPGA platform

NASA Astrophysics Data System (ADS)

Sousa, Ricardo M.; Wäny, Martin; Santos, Pedro; Dias, Morgado

2015-03-01

Centered on Awaiba's NanEye CMOS image sensor family and a FPGA platform with USB3 interface, the aim of this paper is to demonstrate a new technique to synchronize up to 8 individual self-timed cameras with minimal error. Small form factor self-timed camera modules of 1 mm x 1 mm or smaller do not normally allow external synchronization. However, for stereo vision or 3D reconstruction with multiple cameras as well as for applications requiring pulsed illumination it is required to synchronize multiple cameras. In this work, the challenge of synchronizing multiple selftimed cameras with only 4 wire interface has been solved by adaptively regulating the power supply for each of the cameras. To that effect, a control core was created to constantly monitor the operating frequency of each camera by measuring the line period in each frame based on a well-defined sampling signal. The frequency is adjusted by varying the voltage level applied to the sensor based on the error between the measured line period and the desired line period. To ensure phase synchronization between frames, a Master-Slave interface was implemented. A single camera is defined as the Master, with its operating frequency being controlled directly through a PC based interface. The remaining cameras are setup in Slave mode and are interfaced directly with the Master camera control module. This enables the remaining cameras to monitor its line and frame period and adjust their own to achieve phase and frequency synchronization. The result of this work will allow the implementation of smaller than 3mm diameter 3D stereo vision equipment in medical endoscopic context, such as endoscopic surgical robotic or micro invasive surgery.

Image synchronization for 3D application using the NanEye sensor

NASA Astrophysics Data System (ADS)

Sousa, Ricardo M.; Wäny, Martin; Santos, Pedro; Dias, Morgado

2015-03-01

Based on Awaiba's NanEye CMOS image sensor family and a FPGA platform with USB3 interface, the aim of this paper is to demonstrate a novel technique to perfectly synchronize up to 8 individual self-timed cameras. Minimal form factor self-timed camera modules of 1 mm x 1 mm or smaller do not generally allow external synchronization. However, for stereo vision or 3D reconstruction with multiple cameras as well as for applications requiring pulsed illumination it is required to synchronize multiple cameras. In this work, the challenge to synchronize multiple self-timed cameras with only 4 wire interface has been solved by adaptively regulating the power supply for each of the cameras to synchronize their frame rate and frame phase. To that effect, a control core was created to constantly monitor the operating frequency of each camera by measuring the line period in each frame based on a well-defined sampling signal. The frequency is adjusted by varying the voltage level applied to the sensor based on the error between the measured line period and the desired line period. To ensure phase synchronization between frames of multiple cameras, a Master-Slave interface was implemented. A single camera is defined as the Master entity, with its operating frequency being controlled directly through a PC based interface. The remaining cameras are setup in Slave mode and are interfaced directly with the Master camera control module. This enables the remaining cameras to monitor its line and frame period and adjust their own to achieve phase and frequency synchronization. The result of this work will allow the realization of smaller than 3mm diameter 3D stereo vision equipment in medical endoscopic context, such as endoscopic surgical robotic or micro invasive surgery.

Design of Experiments to Study the Impact of Process Parameters on Droplet Size and Development of Non-Invasive Imaging Techniques in Tablet Coating

PubMed Central

Dennison, Thomas J.; Smith, Julian; Hofmann, Michael P.; Bland, Charlotte E.; Badhan, Raj K.; Al-Khattawi, Ali; Mohammed, Afzal R.

2016-01-01

Atomisation of an aqueous solution for tablet film coating is a complex process with multiple factors determining droplet formation and properties. The importance of droplet size for an efficient process and a high quality final product has been noted in the literature, with smaller droplets reported to produce smoother, more homogenous coatings whilst simultaneously avoiding the risk of damage through over-wetting of the tablet core. In this work the effect of droplet size on tablet film coat characteristics was investigated using X-ray microcomputed tomography (XμCT) and confocal laser scanning microscopy (CLSM). A quality by design approach utilising design of experiments (DOE) was used to optimise the conditions necessary for production of droplets at a small (20 μm) and large (70 μm) droplet size. Droplet size distribution was measured using real-time laser diffraction and the volume median diameter taken as a response. DOE yielded information on the relationship three critical process parameters: pump rate, atomisation pressure and coating-polymer concentration, had upon droplet size. The model generated was robust, scoring highly for model fit (R2 = 0.977), predictability (Q2 = 0.837), validity and reproducibility. Modelling confirmed that all parameters had either a linear or quadratic effect on droplet size and revealed an interaction between pump rate and atomisation pressure. Fluidised bed coating of tablet cores was performed with either small or large droplets followed by CLSM and XμCT imaging. Addition of commonly used contrast materials to the coating solution improved visualisation of the coating by XμCT, showing the coat as a discrete section of the overall tablet. Imaging provided qualitative and quantitative evidence revealing that smaller droplets formed thinner, more uniform and less porous film coats. PMID:27548263

Novel, ultra-compact, high-performance, eye-safe laser rangefinder for demanding applications

NASA Astrophysics Data System (ADS)

Silver, M.; Lee, S. T.; Borthwick, A.; Morton, G.; McNeill, C.; McSporran, D.; McRae, I.; McKinlay, G.; Jackson, D.; Alexander, W.

2016-05-01

Compact eye-safe laser rangefinders (LRFs) are a key technology for future sensors. In addition to reduced size, weight and power (SWaP), compact LRFs are increasingly being required to deliver a higher repetition rate, burst mode capability. Burst mode allows acquisition of telemetry data from fast moving targets or while sensing-on-the-move. We will describe a new, ultra-compact, long-range, eye-safe laser rangefinder that incorporates a novel transmitter that can deliver a burst capability. The transmitter is a diode-pumped, erbium:glass, passively Q-switched, solid-state laser which uses design and packaging techniques adopted from the telecom components sector. The key advantage of this approach is that the transmitter can be engineered to match the physical dimensions of the active laser components and the submillimetre sized laser spot. This makes the transmitter significantly smaller than existing designs, leading to big improvements in thermal management, and allowing higher repetition rates. In addition, the design approach leads to devices that have higher reliability, lower cost, and smaller form-factor, than previously possible. We present results from the laser rangefinder that incorporates the new transmitter. The LRF has dimensions (L x W x H) of 100 x 55 x 34 mm and achieves ranges of up to 15km from a single shot, and over a temperature range of -32°C to +60°C. Due to the transmitter's superior thermal performance, the unit is capable of repetition rates of 1Hz continuous operation and short bursts of up to 4Hz. Short bursts of 10Hz have also been demonstrated from the transmitter in the laboratory.

Behavioral inhibition in childhood predicts smaller hippocampal volume in adolescent offspring of parents with panic disorder

PubMed Central

Schwartz, C E; Kunwar, P S; Hirshfeld-Becker, D R; Henin, A; Vangel, M G; Rauch, S L; Biederman, J; Rosenbaum, J F

2015-01-01

Behavioral inhibition (BI) is a genetically influenced behavioral profile seen in 15–20% of 2-year-old children. Children with BI are timid with people, objects and situations that are novel or unfamiliar, and are more reactive physiologically to these challenges as evidenced by higher heart rate, pupillary dilation, vocal cord tension and higher levels of cortisol. BI predisposes to the later development of anxiety, depression and substance abuse. Reduced hippocampal volumes have been observed in anxiety disorders, depression and posttraumatic stress disorder. Animal models have demonstrated that chronic stress can damage the hippocampal formation and implicated cortisol in these effects. We, therefore, hypothesized that the hippocampi of late adolescents who had been behaviorally inhibited as children would be smaller compared with those who had not been inhibited. Hippocampal volume was measured with high-resolution structural magnetic resonance imaging in 43 females and 40 males at 17 years of age who were determined to be BI+ or BI− based on behaviors observed in the laboratory as young children. BI in childhood predicted reduced hippocampal volumes in the adolescents who were offspring of parents with panic disorder, or panic disorder with comorbid major depression. We discuss genetic and environmental factors emanating from both child and parent that may explain these findings. To the best of our knowledge, this is the first study to demonstrate a relationship between the most extensively studied form of temperamentally based human trait anxiety, BI, and hippocampal structure. The reduction in hippocampal volume, as reported by us, suggests a role for the hippocampus in human trait anxiety and anxiety disorder that warrants further investigation. PMID:26196438

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, PAINT OVERSPRAY ARRESTOR KOCH FILTER CORPORATION MULTI-SAK 6FZ159-S

EPA Science Inventory

Paint overspray arrestors (POAs) were evaluated by the Air Pollution Control Technology (APCT) Verification Center. The performance factor verified was the particle filtration efficiency as a function of size for particles smaller than 10 micrometers. The APCT Verification Center...

Ulcerative colitis: pathogenesis, diagnosis, and current treatment.

PubMed

Griffel, L H; Das, K M

1996-01-01

Ulcerative colitis is a chronic inflammatory disease of the colon that affects the rectum and a variable length of contiguous colon. The disease is characterized by rectal bleeding and diarrhea during periods of exacerbation; these symptoms usually abate with treatment. The pathogenic mechanism of ulcerative colitis is believed to be an aberrant immune response in which antibodies are formed against colonic epithelial protein(s). The disease usually presents during the second and third decades of life, with a smaller peak after the age of 60 years. There is a genetic component to ulcerative colitis, with a higher incidence among family members and, particularly, first-degree relatives. Diagnosis depends on several factors, most notably symptoms, demonstration of uniformly inflamed mucosa beginning in the rectum, and exclusion of other causes of colitis, such as infection. There is no medical cure for ulcerative colitis, but medical therapy is effective and can improve or eliminate symptoms in more than 80% of patients. Surgery offers a cure but carries the high price of total colectomy. New surgical methods, such as ileoanal anastomosis, allow for maintenance of bowel continuity and better patient satisfaction.

Parasitic Reactions in Nanosized Silicon Anodes for Lithium-Ion Batteries

DOE PAGES

Gao, Han; Xiao, Lisong; Plumel, Ingo; ...

2017-02-08

When designing nano-Si electrodes for lithium-ion batteries, the detrimental effect of the c-Li 15Si 4 phase formed upon full lithiation is often a concern. In this study, Si nanoparticles with controlled particle sizes and morphology were synthesized and parasitic reactions of the metastable c-Li 15Si 4 phase with the non-aqueous electrolyte was investigated. The use of smaller Si nanoparticles (~ 60 nm) and the addition of fluoroethylene carbonate additive played decisive roles in the parasitic reactions such that the c-Li 15Si 4 phase could disappear at the end of lithiation. This suppression of c-Li 15Si 4 improved cycle life ofmore » the nano-Si electrodes but with a little loss of specific capacity. Also the characteristic c-Li 15Si 4 peak in the dQ/dV plots can be used as an early-stage indicator to cell capacity fade during cycling. Lastly, our findings can contribute to the design guidelines of Si electrodes and allow us to quantify another factor to the performance of the Si electrodes.« less

Abiotic determinants of the historical buildings biodeterioration in the former Auschwitz II-Birkenau concentration and extermination camp.

PubMed

Piotrowska, Małgorzata; Otlewska, Anna; Rajkowska, Katarzyna; Koziróg, Anna; Hachułka, Mariusz; Nowicka-Krawczyk, Paulina; Wolski, Grzegorz J; Gutarowska, Beata; Kunicka-Styczyńska, Alina; Zydzik-Białek, Agnieszka

2014-01-01

The paper presents the results of a study conducted at the Auschwitz-Birkenau State Museum in Oświęcim on the occurrence of biodeterioration. Visual assessment of the buildings revealed signs of deterioration of the buildings in the form of dampness, bulging and crumbling plaster, and wood fiber splitting. The external surfaces, and especially the concrete strips and ground immediately adjoining the buildings, were colonized by bryophytes, lichens, and algae. These organisms developed most intensively close to the ground on the northern sides of the buildings. Inside the buildings, molds and bacteria were not found to develop actively, while algae and wood-decaying fungi occurred locally. The factors conducive to biological corrosion in the studied buildings were excessive dampness of structural partitions close to the ground and a relative air humidity of above 70%, which was connected to ineffective moisture insulation. The influence of temperature was smaller, as it mostly affected the quantitative composition of the microorganisms and the qualitative composition of the algae. Also the impact of light was not very strong, but it was conducive to algae growth.

Silicon Carbide (SiC) MOSFET-based Full-Bridge for Fusion Science Applications

NASA Astrophysics Data System (ADS)

Ziemba, Timothy; Miller, Kenneth; Prager, James; Picard, Julian; Hashim, Akel

2014-10-01

Switching power amplifiers (SPAs) have a wide variety of applications within the fusion science community, including feedback and control systems for dynamic plasma stabilization in tokamaks, inductive and arc plasma sources, Radio Frequency (RF) helicity and flux injection, RF plasma heating and current drive schemes, ion beam generation, and RF pre-ionizer systems. SiC MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities. When comparing SiC and traditional silicon-based MOSFETs, SiC MOSFETs provide higher current carrying capability allowing for smaller package weights and sizes and lower operating temperature. Eagle Harbor Technologies (EHT) is designing, constructing, and testing a SiC MOSFET-based full-bridge SPA. EHT will leverage the proprietary gate drive technology previously developed with the support of a DOE SBIR, which will enable fast, efficient switching in a small form factor. The primary goal is to develop a SiC MOSFET-based SPA for fusion science applications. Work supported in part by the DOE under Contract Number DE-SC0011907.

Bone formation in vivo induced by Cbfa1-carrying adenoviral vectors released from a biodegradable porous β-tricalcium phosphate (β-TCP) material.

PubMed

Uemura, Toshimasa; Kojima, Hiroko

2011-06-01

Overexpression of Cbfa1 (a transcription factor indispensable for osteoblastic differentiation) is expected to induce the formation of bone directly and indirectly in vivo by accelerating osteoblastic differentiation. Adenoviral vectors carrying the cDNA of Cbfa1/til-1(Adv-Cbf1) were allowed to be adsorbed onto porous blocks of β-tricalcium phosphate (β-TCP), a biodegradable ceramic, which were then implanted subcutaneously and orthotopically into bone defects. The adenoviral vectors were released sustainingly by biodegradation, providing long-term expression of the genes. Results of the subcutaneous implantation of Adv-Cbfa1-adsorbed β-TCP/osteoprogenitor cells suggest that a larger amount of bone formed in the pores of the implant than in the control material. Regarding orthotopic implantation into bone defects, the released Adv-Cbfa1 accelerated regeneration in the cortical bone, whereas it induced bone resorption in the marrow cavity. A safer gene transfer using a smaller amount of the vector was achieved using biodegradable porous β-TCP as a carrier.

Bone formation in vivo induced by Cbfa1-carrying adenoviral vectors released from a biodegradable porous β-tricalcium phosphate (β-TCP) material

NASA Astrophysics Data System (ADS)

Uemura, Toshimasa; Kojima, Hiroko

2011-06-01

Overexpression of Cbfa1 (a transcription factor indispensable for osteoblastic differentiation) is expected to induce the formation of bone directly and indirectly in vivo by accelerating osteoblastic differentiation. Adenoviral vectors carrying the cDNA of Cbfa1/til-1(Adv-Cbf1) were allowed to be adsorbed onto porous blocks of β-tricalcium phosphate (β-TCP), a biodegradable ceramic, which were then implanted subcutaneously and orthotopically into bone defects. The adenoviral vectors were released sustainingly by biodegradation, providing long-term expression of the genes. Results of the subcutaneous implantation of Adv-Cbfa1-adsorbed β-TCP/osteoprogenitor cells suggest that a larger amount of bone formed in the pores of the implant than in the control material. Regarding orthotopic implantation into bone defects, the released Adv-Cbfa1 accelerated regeneration in the cortical bone, whereas it induced bone resorption in the marrow cavity. A safer gene transfer using a smaller amount of the vector was achieved using biodegradable porous β-TCP as a carrier.

Design of compact freeform lens for application specific Light-Emitting Diode packaging.

PubMed

Wang, Kai; Chen, Fei; Liu, Zongyuan; Luo, Xiaobing; Liu, Sheng

2010-01-18

Application specific LED packaging (ASLP) is an emerging technology for high performance LED lighting. We introduced a practical design method of compact freeform lens for extended sources used in ASLP. A new ASLP for road lighting was successfully obtained by integrating a polycarbonate compact freeform lens of small form factor with traditional LED packaging. Optical performance of the ASLP was investigated by both numerical simulation based on Monte Carlo ray tracing method and experiments. Results demonstrated that, comparing with traditional LED module integrated with secondary optics, the ASLP had advantages of much smaller size in volume (approximately 1/8), higher system lumen efficiency (approximately 8.1%), lower cost and more convenience for customers to design and assembly, enabling possible much wider applications of LED for general road lighting. Tolerance analyses were also conducted. Installation errors of horizontal and vertical deviations had more effects on the shape and uniformity of radiation pattern compared with rotational deviation. The tolerances of horizontal, vertical and rotational deviations of this lens were 0.11 mm, 0.14 mm and 2.4 degrees respectively, which were acceptable in engineering.

A fast algorithm for multiscale electromagnetic problems using interpolative decomposition and multilevel fast multipole algorithm

NASA Astrophysics Data System (ADS)

Pan, Xiao-Min; Wei, Jian-Gong; Peng, Zhen; Sheng, Xin-Qing

2012-02-01

The interpolative decomposition (ID) is combined with the multilevel fast multipole algorithm (MLFMA), denoted by ID-MLFMA, to handle multiscale problems. The ID-MLFMA first generates ID levels by recursively dividing the boxes at the finest MLFMA level into smaller boxes. It is specifically shown that near-field interactions with respect to the MLFMA, in the form of the matrix vector multiplication (MVM), are efficiently approximated at the ID levels. Meanwhile, computations on far-field interactions at the MLFMA levels remain unchanged. Only a small portion of matrix entries are required to approximate coupling among well-separated boxes at the ID levels, and these submatrices can be filled without computing the complete original coupling matrix. It follows that the matrix filling in the ID-MLFMA becomes much less expensive. The memory consumed is thus greatly reduced and the MVM is accelerated as well. Several factors that may influence the accuracy, efficiency and reliability of the proposed ID-MLFMA are investigated by numerical experiments. Complex targets are calculated to demonstrate the capability of the ID-MLFMA algorithm.

Forbidden fruit? A longitudinal study of Christianity, sex, and marriage.

PubMed

Pedersen, Willy

2014-01-01

Does religion still play a role in explorations of romance and sexuality among adolescents and young adults in a secular society such as Norway? Does it influence the type of living arrangements chosen? A population-based sample (n = 2,454) was followed longitudinally from their midteens to their late 20s using survey and register data. Christian involvement in teenage years was associated with subsequent less "precoital" exploration, less masturbation, delayed sexual intercourse, and a smaller number of sex partners. However, there were no associations with prevalence of same-sex experiences. Christians also postponed initiating romantic relationships and chose marriage over cohabitation. Associations were reduced after controlling for confounding factors but remained significant. Some associations (for example, the form of residential union chosen) were present only in the most "active" Christians. In other areas, such as "precoital explorations" and the age at which intercourse is initiated, Christian norms seem to play a role in much broader segments of the population. The findings indicate that Christianity may continue to influence young Norwegians' experiences of sexuality and cohabitation more than has been expected.

Precursors to speech in infancy: the prediction of speech and language disorders.

PubMed

Oller, D K; Eilers, R E; Neal, A R; Schwartz, H K

1999-01-01

During the canonical stage of infant babbling, infants produce well-formed syllables, often in reduplicated sequences such as "bababa." Although nearly all infants with normal hearing begin the canonical stage by 10 months of age, a few are delayed, and these infants may be of special interest. Recent studies indicate that late onset of canonical babbling may be a predictor of disorders. A simple screening procedure that focuses on canonical babbling was used to evaluate over 3400 infants at risk who were about 10 months of age. Among infants who showed late onset of canonical babbling, fewer than half had been previously diagnosed as having a significant medical problem that might have accounted for the delay. A follow-up study indicated that infants with delayed canonical babbling had smaller production vocabularies at 18, 24, and 30 months than did infants in the control group. The results suggest that late onset of canonical babbling, a factor that can be monitored effectively through an interview with a parent, can predict delay in the onset of speech production.

Technology-design-manufacturing co-optimization for advanced mobile SoCs

NASA Astrophysics Data System (ADS)

Yang, Da; Gan, Chock; Chidambaram, P. R.; Nallapadi, Giri; Zhu, John; Song, S. C.; Xu, Jeff; Yeap, Geoffrey

2014-03-01

How to maintain the Moore's Law scaling beyond the 193 immersion resolution limit is the key question semiconductor industry needs to answer in the near future. Process complexity will undoubtfully increase for 14nm node and beyond, which brings both challenges and opportunities for technology development. A vertically integrated design-technologymanufacturing co-optimization flow is desired to better address the complicated issues new process changes bring. In recent years smart mobile wireless devices have been the fastest growing consumer electronics market. Advanced mobile devices such as smartphones are complex systems with the overriding objective of providing the best userexperience value by harnessing all the technology innovations. Most critical system drivers are better system performance/power efficiency, cost effectiveness, and smaller form factors, which, in turns, drive the need of system design and solution with More-than-Moore innovations. Mobile system-on-chips (SoCs) has become the leading driver for semiconductor technology definition and manufacturing. Here we highlight how the co-optimization strategy influenced architecture, device/circuit, process technology and package, in the face of growing process cost/complexity and variability as well as design rule restrictions.

[Recurrent right atrial thrombus in a patient with atrial fibrillation and heart failure].

PubMed

Elikowski, Waldemar; Wróblewski, Dariusz; Małek-Elikowska, Małgorzata; Mazurek, Andrzej; Foremska-Iciek, Joanna; Łazowski, Stanisław

2015-11-01

Atrial fibrillation and heart failure are factors predisposing to locally formed intracardiac thrombosis, which is usually localized in left-sided chambers. A case report. The authors present a case of a 50-year-old male with permanent atrial fibrillation and dilated cardiomyopathy in whom recurrent right atrial thrombus was observed. Initially, the lesion was detected in echocardiography while he was hospitalized due to extensive right-sided pneumonia. The thrombus was successfully treated with heparin, followed by warfarin. Even though the patient continued warfarin use properly, there was recurrence of the thrombus two years later during a new episode of heart failure exacerbation. Because the thrombus was resistant to intensified anticoagulation, cardiac surgery was needed. A large (30 x 25 mm) pedunculated thrombus, as well as two smaller ones (each of 10 x 10 mm) attached closely to the atrial wall and previously not detected either by echocardiography or by magnetic resonance imaging, were excited. A partially organized pattern of the thrombi in histological examination can explain lack of anticoagulation effectiveness. © 2015 MEDPRESS.

MINER - A Mobile Imager of Neutrons for Emergency Responders

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

Goldsmith, John E. M.; Brennan, James S.; Gerling, Mark D

2014-10-01

We have developed a mobile fast neutron imaging platform to enhance the capabilities of emergency responders in the localization and characterization of special nuclear material. This mobile imager of neutrons for emergency responders (MINER) is based on the Neutron Scatter Camera, a large segmented imaging system that was optimized for large-area search applications. Due to the reduced size and power requirements of a man-portable system, MINER has been engineered to fit a much smaller form factor, and to be operated from either a battery or AC power. We chose a design that enabled omnidirectional (4π) imaging, with only a ~twofoldmore » decrease in sensitivity compared to the much larger neutron scatter cameras. The system was designed to optimize its performance for neutron imaging and spectroscopy, but it does also function as a Compton camera for gamma imaging. This document outlines the project activities, broadly characterized as system development, laboratory measurements, and deployments, and presents sample results in these areas. Additional information can be found in the documents that reside in WebPMIS.« less

New perspective on single-radiator multiple-port antennas for adaptive beamforming applications.

PubMed

Byun, Gangil; Choo, Hosung

2017-01-01

One of the most challenging problems in recent antenna engineering fields is to achieve highly reliable beamforming capabilities in an extremely restricted space of small handheld devices. In this paper, we introduce a new perspective on single-radiator multiple-port (SRMP) antenna to alter the traditional approach of multiple-antenna arrays for improving beamforming performances with reduced aperture sizes. The major contribution of this paper is to demonstrate the beamforming capability of the SRMP antenna for use as an extremely miniaturized front-end component in more sophisticated beamforming applications. To examine the beamforming capability, the radiation properties and the array factor of the SRMP antenna are theoretically formulated for electromagnetic characterization and are used as complex weights to form adaptive array patterns. Then, its fundamental performance limits are rigorously explored through enumerative studies by varying the dielectric constant of the substrate, and field tests are conducted using a beamforming hardware to confirm the feasibility. The results demonstrate that the new perspective of the SRMP antenna allows for improved beamforming performances with the ability of maintaining consistently smaller aperture sizes compared to the traditional multiple-antenna arrays.

Cinematic camera emulation using two-dimensional color transforms

NASA Astrophysics Data System (ADS)

McElvain, Jon S.; Gish, Walter

2015-02-01

For cinematic and episodic productions, on-set look management is an important component of the creative process, and involves iterative adjustments of the set, actors, lighting and camera configuration. Instead of using the professional motion capture device to establish a particular look, the use of a smaller form factor DSLR is considered for this purpose due to its increased agility. Because the spectral response characteristics will be different between the two camera systems, a camera emulation transform is needed to approximate the behavior of the destination camera. Recently, twodimensional transforms have been shown to provide high-accuracy conversion of raw camera signals to a defined colorimetric state. In this study, the same formalism is used for camera emulation, whereby a Canon 5D Mark III DSLR is used to approximate the behavior a Red Epic cinematic camera. The spectral response characteristics for both cameras were measured and used to build 2D as well as 3x3 matrix emulation transforms. When tested on multispectral image databases, the 2D emulation transforms outperform their matrix counterparts, particularly for images containing highly chromatic content.

Mechanisms for Differential Protein Production in Toxin–Antitoxin Systems

PubMed Central

Deter, Heather S.; Jensen, Roderick V.; Mather, William H.; Butzin, Nicholas C.

2017-01-01

Toxin–antitoxin (TA) systems are key regulators of bacterial persistence, a multidrug-tolerant state found in bacterial species that is a major contributing factor to the growing human health crisis of antibiotic resistance. Type II TA systems consist of two proteins, a toxin and an antitoxin; the toxin is neutralized when they form a complex. The ratio of antitoxin to toxin is significantly greater than 1.0 in the susceptible population (non-persister state), but this ratio is expected to become smaller during persistence. Analysis of multiple datasets (RNA-seq, ribosome profiling) and results from translation initiation rate calculators reveal multiple mechanisms that ensure a high antitoxin-to-toxin ratio in the non-persister state. The regulation mechanisms include both translational and transcriptional regulation. We classified E. coli type II TA systems into four distinct classes based on the mechanism of differential protein production between toxin and antitoxin. We find that the most common regulation mechanism is translational regulation. This classification scheme further refines our understanding of one of the fundamental mechanisms underlying bacterial persistence, especially regarding maintenance of the antitoxin-to-toxin ratio. PMID:28677629

Joint fit of Warm Absorbers in COS and HETG spectra of NGC 3783

NASA Astrophysics Data System (ADS)

Fu, Xiao-Dan; Zhang, Shui-Nai; Sun, Wei; Niu, Shu; Ji, Li

2017-09-01

Warm Absorbers (WAs), as an important form of AGN outflows, show absorption in both the UV and X-ray bands. Using XSTAR generated photoionization models, for the first time we present a joint fit to the simultaneous observations of HST/COS and Chandra/HETG on NGC 3783. A total of five WAs explain well all absorption features from the AGN outflows, which are spread over a wide range of parameters: ionization parameter logξ from 0.6 to 3.8, column density log {N}{{H}} from 19.5 to 22.3 cm-2, velocity v from 380 to 1060 km s-1, and covering factor from 0.33 to 0.75. Not all the five WAs are consistent in pressure. Two of them are likely different parts of the same absorbing gas, and two of the other WAs may be smaller discrete clouds that are blown out from the inner region of the torus at different periods. The five WAs suggest a total mass outflowing rate within the range of 0.22-4.1 solar mass per year.

Reproductive biology of the Green Ground Snake Erythrolamprus poecilogyrus sublineatus (Serpentes: Dipsadidae) in Subtropical Brazil.

PubMed

Quintela, Fernando M; Marques, Wiliam C; Loebmann, Daniel

2017-01-01

We investigated reproductive features of the dipsadid snake Erythrolamprus poecilogyrus sublineatus in the southernmost Brazilian coast, a subtropical region characterized by well-marked seasons. Females are significantly smaller than males, have a shorter tail, and reach sexual maturity at later times along their development. In contrast to tropical subspecies, E. p. sublineatus females presented a seasonal pattern, with secondary follicles occurring from late winter to early autumn and egg production restricted to the whole spring and early summer. Males presented seasonal variation in testes volume (increase in autumn and decrease in winter) while no significant seasonal variation was found in ductus deferens width. The number of oviductal eggs varied from two to nine, thus, real fecundity is also inferior than that observed in tropical E. poecilogyrus forms. Considering the thermal requirements for reproduction, it is possible that the colder climatic conditions of the southern Brazilian coast have shaped the seasonal reproductive pattern in E. p. sublineatus. The shorter body size of this subspecies may also represent a conditioning factor of low fecundity.

D2O clusters isolated in rare-gas solids: Dependence of infrared spectrum on concentration, deposition rate, heating temperature, and matrix material

NASA Astrophysics Data System (ADS)

Shimazaki, Yoichi; Arakawa, Ichiro; Yamakawa, Koichiro

2018-04-01

The infrared absorption spectra of D2O monomers and clusters isolated in rare-gas matrices were systematically reinvestigated under the control of the following factors: the D2O concentration, deposition rate, heating temperature, and rare-gas species. We clearly show that the cluster-size distribution is dependent on not only the D2O concentration but also the deposition rate of a sample; as the rate got higher, smaller clusters were preferentially formed. Under the heating procedures at different temperatures, the cluster-size growth was successfully observed. Since the monomer diffusion was not enough to balance the changes in the column densities of the clusters, the dimer diffusion was likely to contribute the cluster growth. The frequencies of the bonded-OD stretches of (D2O)k with k = 2-6 were almost linearly correlated with the square root of the critical temperature of the matrix material. Additional absorption peaks of (D2O)2 and (D2O)3 in a Xe matrix were assigned to the species trapped in tight accommodation sites.

Punishment in the form of shared cost promotes altruism in the cooperative dilemma games.

PubMed

Zhang, Chunyan; Zhu, Yuying; Chen, Zengqiang; Zhang, Jianlei

2017-05-07

One phenomenon or social institution often observed in multi-agent interactions is the altruistic punishment, i.e. the punishment of unfair behavior by others at a personal cost. Inspired by the works focusing on punishment and the intricate mechanism behind it, we theoretically study the strategy evolution in the framework of two-strategy game models with the punishment on defectors, moreover, the cost of punishing will be evenly shared among the cooperators. Theoretical computations suggest that larger punishment on defectors or smaller punishment cost incurred by cooperators will enhance the fixation of altruistic cooperation in the population. Through the replicate dynamics, the group size of the randomly selected individuals from the sufficiently large population will notably affect the strategy evolution in populations nested within a dilemma. By theoretical modeling the concept of shared cost for punishment from one point of view, our findings underscore the importance of punishment with shared cost as a factor in real-life decisions in an evolutionary game context. Copyright © 2017 Elsevier Ltd. All rights reserved.

Observations from the High Resolution Imaging Science Experiment (HiRISE): Martian dust devils in Gusev and Russell craters

NASA Astrophysics Data System (ADS)

Verba, Circe A.; Geissler, Paul E.; Titus, Timothy N.; Waller, Devin

2010-09-01

Two areas targeted for repeated imaging by detailed High Resolution Imaging Science Experiment (HiRISE) observations allow us to examine morphological differences and monitor seasonal variations of Martian dust devil tracks at two quite different locations. Russell crater (53.3°S, 12.9°E) is regularly imaged to study seasonal processes including deposition and sublimation of CO2 frost. Gusev crater (14.6°S, 175.4°E) has been frequently imaged in support of the Mars Exploration Rover mission. Gusev crater provides the first opportunity to compare “ground truth” orbital observations of dust devil tracks to surface observations of active dust plumes. Orbital observations show that dust devil tracks are rare, forming at a rate <1/110 that of the occurrence of active dust plumes estimated from Spirit's surface observations. Furthermore, the tracks observed from orbit are wider than typical plume diameters observed by Spirit. We conclude that the tracks in Gusev are primarily formed by rare, large dust devils. Smaller dust devils fail to leave tracks that are visible from orbit, perhaps because of limited surface excavation depths. Russell crater displays more frequent, smaller sinuous tracks than Gusev. This may be due to the thin dust cover in Russell, allowing smaller dust devils to penetrate through the bright dust layer and leave conspicuous tracks. The start of the dust devil season and peak activity are delayed in Russell in comparison to Gusev, likely because of its more southerly location. Dust devils in both sites travel in directions consistent with general circulation model (GCM)-predicted winds, confirming a laboratory-derived approach to determining dust devil travel directions based on track morphology.

Hubble's View of the Polar Ring of Arp 230

NASA Image and Video Library

2015-01-30

This Picture of the Week shows Arp 230, also known as IC 51, observed by the NASA/ESA Hubble Space Telescope. Arp 230 is a galaxy of an uncommon or peculiar shape, and is therefore part of the Atlas of Peculiar Galaxies produced by Halton Arp. Its irregular shape is thought to be the result of a violent collision with another galaxy sometime in the past. The collision could also be held responsible for the formation of the galaxy’s polar ring. The outer ring surrounding the galaxy consists of gas and stars and rotates over the poles of the galaxy. It is thought that the orbit of the smaller of the two galaxies that created Arp 230 was perpendicular to the disk of the second, larger galaxy when they collided. In the process of merging the smaller galaxy would have been ripped apart and may have formed the polar ring structure astronomers can observe today. Arp 230 is quite small for a lenticular galaxy, so the two original galaxies forming it must both have been smaller than the Milky Way. A lenticular galaxy is a galaxy with a prominent central bulge and a disk, but no clear spiral arms. They are classified as intermediate between an elliptical galaxy and a spiral galaxy. Credit: ESA/Hubble & NASA, Acknowledgement: Flickr user Det58 NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Seafloor geomorphology of western Antarctic Peninsula bays: a signature of ice flow behaviour

NASA Astrophysics Data System (ADS)

Munoz, Yuribia P.; Wellner, Julia S.

2018-01-01

Glacial geomorphology is used in Antarctica to reconstruct ice advance during the Last Glacial Maximum and subsequent retreat across the continental shelf. Analogous geomorphic assemblages are found in glaciated fjords and are used to interpret the glacial history and glacial dynamics in those areas. In addition, understanding the distribution of submarine landforms in bays and the local controls exerted on ice flow can help improve numerical models by providing constraints through these drainage areas. We present multibeam swath bathymetry from several bays in the South Shetland Islands and the western Antarctic Peninsula. The submarine landforms are described and interpreted in detail. A schematic model was developed showing the features found in the bays: from glacial lineations and moraines in the inner bay to grounding zone wedges and drumlinoid features in the middle bay and streamlined features and meltwater channels in the outer bay areas. In addition, we analysed local variables in the bays and observed the following: (1) the number of landforms found in the bays scales to the size of the bay, but the geometry of the bays dictates the types of features that form; specifically, we observe a correlation between the bay width and the number of transverse features present in the bays. (2) The smaller seafloor features are present only in the smaller glacial systems, indicating that short-lived atmospheric and oceanographic fluctuations, responsible for the formation of these landforms, are only recorded in these smaller systems. (3) Meltwater channels are abundant on the seafloor, but some are subglacial, carved in bedrock, and some are modern erosional features, carved on soft sediment. Lastly, based on geomorphological evidence, we propose the features found in some of the proximal bay areas were formed during a recent glacial advance, likely the Little Ice Age.

Direct lifts of coupled cell networks

NASA Astrophysics Data System (ADS)

Dias, A. P. S.; Moreira, C. S.

2018-04-01

In networks of dynamical systems, there are spaces defined in terms of equalities of cell coordinates which are flow-invariant under any dynamical system that has a form consistent with the given underlying network structure—the network synchrony subspaces. Given a network and one of its synchrony subspaces, any system with a form consistent with the network, restricted to the synchrony subspace, defines a new system which is consistent with a smaller network, called the quotient network of the original network by the synchrony subspace. Moreover, any system associated with the quotient can be interpreted as the restriction to the synchrony subspace of a system associated with the original network. We call the larger network a lift of the smaller network, and a lift can be interpreted as a result of the cellular splitting of the smaller network. In this paper, we address the question of the uniqueness in this lifting process in terms of the networks’ topologies. A lift G of a given network Q is said to be direct when there are no intermediate lifts of Q between them. We provide necessary and sufficient conditions for a lift of a general network to be direct. Our results characterize direct lifts using the subnetworks of all splitting cells of Q and of all split cells of G. We show that G is a direct lift of Q if and only if either the split subnetwork is a direct lift or consists of two copies of the splitting subnetwork. These results are then applied to the class of regular uniform networks and to the special classes of ring networks and acyclic networks. We also illustrate that one of the applications of our results is to the lifting bifurcation problem.

Progress towards 3-cell superconducting traveling wave cavity cryogenic test

NASA Astrophysics Data System (ADS)

Kostin, R.; Avrakhov, P.; Kanareykin, A.; Yakovlev, V.; Solyak, N.

2017-12-01

This paper describes a superconducting L-band travelling wave cavity for electron linacs as an alternative to the 9-cell superconducting standing wave Tesla type cavity. A superconducting travelling wave cavity may provide 20-40% higher accelerating gradient by comparison with conventional cavities. This feature arises from an opportunity to use a smaller phase advance per cell which increases the transit time factor and affords the opportunity to use longer cavities because of its significantly smaller sensitivity to manufacturing errors. Two prototype superconducting travelling wave cavities were designed and manufactured for a high gradient travelling wave demonstration at cryogenic temperature. This paper presents the main milestones achieved towards this test.

Productive Vocabulary among Three Groups of Bilingual American Children: Comparison and Prediction

PubMed Central

Cote, Linda R.; Bornstein, Marc H.

2015-01-01

The importance of input factors for bilingual children’s vocabulary development was investigated. Forty-seven Argentine, 42 South Korean, 51 European American, 29 Latino immigrant, 26 Japanese immigrant, and 35 Korean immigrant mothers completed checklists of their 20-month-old children’s productive vocabularies. Bilingual children’s vocabulary sizes in each language separately were consistently smaller than their monolingual peers but only Latino bilingual children had smaller total vocabularies than monolingual children. Bilingual children’s vocabulary sizes were similar to each other. Maternal acculturation predicted the amount of input in each language, which then predicted children’s vocabulary size in each language. Maternal acculturation also predicted children’s English-language vocabulary size directly. PMID:25620820

Stimulus factors in motion perception and spatial orientation

NASA Technical Reports Server (NTRS)

Post, R. B.; Johnson, C. A.

1984-01-01

The Malcolm horizon utilizes a large projected light stimulus Peripheral Vision Horizon Device (PVHD) as an attitude indicator in order to achieve a more compelling sense of roll than is obtained with smaller devices. The basic principle is that the larger stimulus is more similar to visibility of a real horizon during roll, and does not require fixation and attention to the degree that smaller displays do. Successful implementation of such a device requires adjustment of the parameters of the visual stimulus so that its effects on motion perception and spatial orientation are optimized. With this purpose in mind, the effects of relevant image variables on the perception of object motion, self motion and spatial orientation are reviewed.

The sensitivity of tokamak magnetohydrodynamics stability on the edge equilibrium

NASA Astrophysics Data System (ADS)

Zheng, L. J.; Kotschenreuther, M. T.; Valanju, P.

2017-10-01

Due to the X-point singularity, the safety factor tends to infinity as approaching to the last closed flux surface. The numerical treatments of the near X-point behavior become challenging both for equilibrium and stability. The usual solution is to cut off a small fraction of edge region for system stability evaluation or simply use an up-down symmetric equilibrium without X-point as an approximation. In this work, we assess the sensitivity of this type of equilibrium treatments on the stability calculation. It is found that the system stability can depend strongly on the safety factor value (qa) at the edge after the cutting-off. When the edge safety factor value falls in the vicinity of a rational mode number (referred to as the resonant gap), the system becomes quite unstable due to the excitation of the peeling type modes. Instead, when the edge safety factor is outside the resonant gaps, the system is much more stable and the predominant modes become the usual external kink (or ballooning and infernal) type. It is also found that the resonant gaps become smaller and smaller as qa increases. The ideal magnetohydrodynamic peeling ballooning stability diagram is widely used to explain the experimental observations, and the current results indicate that the conventional peeling ballooning stability diagram based on the simplified equilibrium needs to be reexamined.

The effects of altered N-linked oligosaccharide structures on maturation and targeting of lysosomal enzymes in Dictyostelium discoideum.

PubMed

Freeze, H H; Koza-Taylor, P; Saunders, A; Cardelli, J A

1989-11-15

We have examined the relationship of N-linked oligosaccharide structures to the proper targeting and proteolytic processing of two lysosomal enzymes, alpha-mannosidase and beta-glucosidase, in the slime mold Dictyostelium discoideum. Two different mutant strains, HL241 and HL243, each synthesize the same nonglucosylated, truncated, lipid-linked oligosaccharide precursor, Man6GlcNAc2. [3H]Mannose-labeled N-linked oligosaccharides were studied following their release from immunoprecipitated alpha-mannosidase and beta-glucosidase by digestion with peptide:N-glycosidase F. The oligosaccharides from both mutants resembled each other, but they were smaller and contained fewer anionic groups than those from the wild-type. The oligosaccharides from the mutants strains were reduced in sulfate and Man-6-P content, and all Man-6-P was in the form of acid-stable phosphodiesters. Pulse-chase radiolabeling experiments using [35S] methionine indicated that the precursor forms of both enzymes were smaller than wild-type, and that this difference was due solely to differences in N-linked oligosaccharides. The precursor forms of the enzymes were not over-secreted, but appeared to be proteolytically processed into mature forms at approximately 50% the rate of wild-type. This is mainly due to their prolonged retention in the rough endoplasmic reticulum, but, ultimately, both enzymes were properly targeted to lysosomes. These studies indicate that a reduction in the amount of sulfation, phosphorylation or size of the N-linked oligosaccharides in these mutants is not critical for the proteolytic processing and targeting of the lysosomal enzymes, but that these changes may influence their rate of exit from the rough endoplasmic reticulum.

Frictional behaviour of sandstone: A sample-size dependent triaxial investigation

NASA Astrophysics Data System (ADS)

Roshan, Hamid; Masoumi, Hossein; Regenauer-Lieb, Klaus

2017-01-01

Frictional behaviour of rocks from the initial stage of loading to final shear displacement along the formed shear plane has been widely investigated in the past. However the effect of sample size on such frictional behaviour has not attracted much attention. This is mainly related to the limitations in rock testing facilities as well as the complex mechanisms involved in sample-size dependent frictional behaviour of rocks. In this study, a suite of advanced triaxial experiments was performed on Gosford sandstone samples at different sizes and confining pressures. The post-peak response of the rock along the formed shear plane has been captured for the analysis with particular interest in sample-size dependency. Several important phenomena have been observed from the results of this study: a) the rate of transition from brittleness to ductility in rock is sample-size dependent where the relatively smaller samples showed faster transition toward ductility at any confining pressure; b) the sample size influences the angle of formed shear band and c) the friction coefficient of the formed shear plane is sample-size dependent where the relatively smaller sample exhibits lower friction coefficient compared to larger samples. We interpret our results in terms of a thermodynamics approach in which the frictional properties for finite deformation are viewed as encompassing a multitude of ephemeral slipping surfaces prior to the formation of the through going fracture. The final fracture itself is seen as a result of the self-organisation of a sufficiently large ensemble of micro-slip surfaces and therefore consistent in terms of the theory of thermodynamics. This assumption vindicates the use of classical rock mechanics experiments to constrain failure of pressure sensitive rocks and the future imaging of these micro-slips opens an exciting path for research in rock failure mechanisms.

Floating seal system for rotary devices

DOEpatents

Banasiuk, Hubert A.

1983-01-01

This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10.degree. to about 30.degree. in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device.

On the Time Course of Accessing Meaning in a Second Language: An Electrophysiological and Behavioral Investigation of Translation Recognition

PubMed Central

Guo, Taomei; Misra, Maya; Tam, Joyce W.; Kroll, Judith F.

2012-01-01

In 2 experiments, relatively proficient Chinese–English bilinguals decided whether Chinese words were the correct translations of English words. Critical trials were those on which incorrect translations were related in lexical form or meaning to the correct translation. In Experiment 1, behavioral interference was revealed for both distractor types, but event-related potentials (ERPs) revealed a different time course for the 2 conditions. Semantic distractors elicited effects primarily on the N400 and late positive component (LPC), with a smaller N400 and a smaller LPC over the posterior scalp but a larger LPC over the anterior scalp relative to unrelated controls. In contrast, translation form distractors elicited a larger P200 and a larger LPC than did unrelated controls. To determine whether the translation form effects were enabled by the relatively long, 750-ms stimulus onset asynchrony (SOA) between words, a 2nd ERP experiment was conducted using a shorter, 300-ms, SOA. The behavioral results revealed interference for both types of distractors, but the ERPs again revealed different loci for the 2 effects. Taken together, the data suggest that proficient bilinguals activate 1st-language translations of words in the 2nd language after they have accessed the meaning of those words. The implications of this pattern for claims about the nature of cross-language activation when bilinguals read in 1 or both languages are discussed. PMID:22686844

Floating seal system for rotary devices

DOEpatents

Banasiuk, H.A.

1983-08-23

This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10[degree] to about 30[degree] in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device. 5 figs.

Stellar Absorption Line Analysis of Local Star-forming Galaxies: The Relation between Stellar Mass, Metallicity, Dust Attenuation, and Star Formation Rate

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

Jabran Zahid, H.; Kudritzki, Rolf-Peter; Ho, I-Ting

We analyze the optical continuum of star-forming galaxies in the Sloan Digital Sky Survey by fitting stacked spectra with stellar population synthesis models to investigate the relation between stellar mass, stellar metallicity, dust attenuation, and star formation rate. We fit models calculated with star formation and chemical evolution histories that are derived empirically from multi-epoch observations of the stellar mass–star formation rate and the stellar mass–gas-phase metallicity relations, respectively. We also fit linear combinations of single-burst models with a range of metallicities and ages. Star formation and chemical evolution histories are unconstrained for these models. The stellar mass–stellar metallicity relationsmore » obtained from the two methods agree with the relation measured from individual supergiant stars in nearby galaxies. These relations are also consistent with the relation obtained from emission-line analysis of gas-phase metallicity after accounting for systematic offsets in the gas-phase metallicity. We measure dust attenuation of the stellar continuum and show that its dependence on stellar mass and star formation rate is consistent with previously reported results derived from nebular emission lines. However, stellar continuum attenuation is smaller than nebular emission line attenuation. The continuum-to-nebular attenuation ratio depends on stellar mass and is smaller in more massive galaxies. Our consistent analysis of stellar continuum and nebular emission lines paves the way for a comprehensive investigation of stellar metallicities of star-forming and quiescent galaxies.« less

Myxobolus goensis n. sp. (Myxozoa, Myxosporea, Myxobolidae), a parasite of the gills of Mugil cephalus (Osteichthyes, Mugilidae) from Goa, India.

PubMed

Eiras, J C; D'Souza, J

2004-09-01

Two species of Myxobolus are reported from the gills of Mugil cephalus collected at Goa, India: M. goensis n. sp. and M. parvus Shulman, 1962. Myxobolus goensis n. sp. forms digitiform or rounded plasmodia between the gill rakers. Their spores are oval in frontal view, with tapered anterior extremity, and lemon-shaped in lateral view, measuring 9.7 (9.5-10.5) microm in length, 6.6 (6-7.5) microm in width, and 5.2 (5-6) microm in thickness. The polar capsules are pyriform and unequal in size. The larger ones are 5.3 (4.5-6) microm long and 2.4 (2-3) microm wide; the smaller ones are 2.4 (2-3) microm long and 1.8 (1.5-2) microm wide. The polar filament forms five turns aligned perpendicularly to the longitudinal axis of the larger polar capsules. Within the smaller polar capsules the polar filament is difficult to observe and, apparently, forms three coils. The spores are distinctly different from other Myxobolus species infecting M. cephalus and other Mugil spp. Furthermore, the present material is also different from 204 Myxobolus species presenting differently sized polar capsules, representing nearly all the known species with this characteristic. The fact that only the M. cephalus specimens were infected among a sample of 206 fish specimens, comprising 27 different species, strongly suggests that this parasite is specific to M. cephalus.

Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements

PubMed Central

Neumann, Gregory A.; Zuber, Maria T.; Wieczorek, Mark A.; Head, James W.; Baker, David M. H.; Solomon, Sean C.; Smith, David E.; Lemoine, Frank G.; Mazarico, Erwan; Sabaka, Terence J.; Goossens, Sander J.; Melosh, H. Jay; Phillips, Roger J.; Asmar, Sami W.; Konopliv, Alexander S.; Williams, James G.; Sori, Michael M.; Soderblom, Jason M.; Miljković, Katarina; Andrews-Hanna, Jeffrey C.; Nimmo, Francis; Kiefer, Walter S.

2015-01-01

Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population. PMID:26601317

Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements.

PubMed

Neumann, Gregory A; Zuber, Maria T; Wieczorek, Mark A; Head, James W; Baker, David M H; Solomon, Sean C; Smith, David E; Lemoine, Frank G; Mazarico, Erwan; Sabaka, Terence J; Goossens, Sander J; Melosh, H Jay; Phillips, Roger J; Asmar, Sami W; Konopliv, Alexander S; Williams, James G; Sori, Michael M; Soderblom, Jason M; Miljković, Katarina; Andrews-Hanna, Jeffrey C; Nimmo, Francis; Kiefer, Walter S

2015-10-01

Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population.

Heparin-binding epidermal growth factor expression in KATO-III cells after Helicobacter pylori stimulation under the influence of strychnos Nux vomica and Calendula officinalis.

PubMed

Hofbauer, Roland; Pasching, Eva; Moser, Doris; Frass, Michael

2010-07-01

Previous studies have shown the stimulating effect of Helicobacter pylori on the gene expression of heparin-binding epidermal growth factor (HB-EGF) using the gastric epithelial cell line KATO-III. Strychnos Nux vomica (Nux vomica) and Calendula officinalis are used in highly diluted form in homeopathic medicine to treat patients suffering from gastritis and gastric ulcers. To investigate the influence of Nux vomica and Calendula officinalis on HB-EGF-like growth factor gene expression in KATO-III cells under the stimulation of H. pylori strain N6 using real-time PCR with and without addition of Nux vomica and Calendula officinalis as a 10c or 12c potency. Baseline expression and stimulation were similar to previous experiments, addition of Nux vomica 10c and Calendula officinalis 10c in a 43% ethanolic solution led to a significant reduction of H. pylori induced increase in gene expression of HB-EGF (reduced to 53.12+/-0.95% and 75.32+/-1.16% vs. control; p<0.05), respectively. Nux vomica 12c reduced HB-EGF gene expression even in dilutions beyond Avogadro's number (55.77+/-1.09%; p<0.05). Nux vomica 12c in a 21.5% ethanol showed a smaller effect (71.80+/-3.91%, p<0.05). This effect was only be observed when the drugs were primarily prepared in ethanol, not in aqueous solutions. The data suggest that both drugs prepared in ethanolic solution are potent inhibitors of H. pylori induced gene expression. 2010 Elsevier Ltd. All rights reserved.

Diagnosing and Correcting Mass Accuracy and Signal Intensity Error Due to Initial Ion Position Variations in a MALDI TOFMS

NASA Astrophysics Data System (ADS)

Malys, Brian J.; Piotrowski, Michelle L.; Owens, Kevin G.

2018-02-01

Frustrated by worse than expected error for both peak area and time-of-flight (TOF) in matrix assisted laser desorption ionization (MALDI) experiments using samples prepared by electrospray deposition, it was finally determined that there was a correlation between sample location on the target plate and the measured TOF/peak area. Variations in both TOF and peak area were found to be due to small differences in the initial position of ions formed in the source region of the TOF mass spectrometer. These differences arise largely from misalignment of the instrument sample stage, with a smaller contribution arising from the non-ideal shape of the target plates used. By physically measuring the target plates used and comparing TOF data collected from three different instruments, an estimate of the magnitude and direction of the sample stage misalignment was determined for each of the instruments. A correction method was developed to correct the TOFs and peak areas obtained for a given combination of target plate and instrument. Two correction factors are determined, one by initially collecting spectra from each sample position used and another by using spectra from a single position for each set of samples on a target plate. For TOF and mass values, use of the correction factor reduced the error by a factor of 4, with the relative standard deviation (RSD) of the corrected masses being reduced to 12-24 ppm. For the peak areas, the RSD was reduced from 28% to 16% for samples deposited twice onto two target plates over two days.

Diagnosing and Correcting Mass Accuracy and Signal Intensity Error Due to Initial Ion Position Variations in a MALDI TOFMS

NASA Astrophysics Data System (ADS)

Malys, Brian J.; Piotrowski, Michelle L.; Owens, Kevin G.

2017-12-01

Frustrated by worse than expected error for both peak area and time-of-flight (TOF) in matrix assisted laser desorption ionization (MALDI) experiments using samples prepared by electrospray deposition, it was finally determined that there was a correlation between sample location on the target plate and the measured TOF/peak area. Variations in both TOF and peak area were found to be due to small differences in the initial position of ions formed in the source region of the TOF mass spectrometer. These differences arise largely from misalignment of the instrument sample stage, with a smaller contribution arising from the non-ideal shape of the target plates used. By physically measuring the target plates used and comparing TOF data collected from three different instruments, an estimate of the magnitude and direction of the sample stage misalignment was determined for each of the instruments. A correction method was developed to correct the TOFs and peak areas obtained for a given combination of target plate and instrument. Two correction factors are determined, one by initially collecting spectra from each sample position used and another by using spectra from a single position for each set of samples on a target plate. For TOF and mass values, use of the correction factor reduced the error by a factor of 4, with the relative standard deviation (RSD) of the corrected masses being reduced to 12-24 ppm. For the peak areas, the RSD was reduced from 28% to 16% for samples deposited twice onto two target plates over two days. [Figure not available: see fulltext.