The Nature of the Unresolved Extragalactic Cosmic Soft X-Ray Background

NASA Technical Reports Server (NTRS)

Cappelluti, N.; Ranalli, P.; Roncarelli, M.; Arevalo, P.; Zamorani, G.; Comastri, A.; Gilli, R.; Rovilos, E.; Vignali, C.; Allevato, V.;

Efficiency of super-Eddington magnetically-arrested accretion

NASA Astrophysics Data System (ADS)

McKinney, Jonathan C.; Dai, Lixin; Avara, Mark J.

2015-11-01

The radiative efficiency of super-Eddington accreting black holes (BHs) is explored for magnetically-arrested discs, where magnetic flux builds-up to saturation near the BH. Our three-dimensional general relativistic radiation magnetohydrodynamic (GRRMHD) simulation of a spinning BH (spin a/M = 0.8) accreting at ˜50 times Eddington shows a total efficiency ˜50 per cent when time-averaged and total efficiency ≳ 100 per cent in moments. Magnetic compression by the magnetic flux near the rotating BH leads to a thin disc, whose radiation escapes via advection by a magnetized wind and via transport through a low-density channel created by a Blandford-Znajek (BZ) jet. The BZ efficiency is sub-optimal due to inertial loading of field lines by optically thick radiation, leading to BZ efficiency ˜40 per cent on the horizon and BZ efficiency ˜5 per cent by r ˜ 400rg (gravitational radii) via absorption by the wind. Importantly, radiation escapes at r ˜ 400rg with efficiency η ≈ 15 per cent (luminosity L ˜ 50LEdd), similar to η ≈ 12 per cent for a Novikov-Thorne thin disc and beyond η ≲ 1 per cent seen in prior GRRMHD simulations or slim disc theory. Our simulations show how BH spin, magnetic field, and jet mass-loading affect these radiative and jet efficiencies.

Human factors paradigm and customer care perceptions.

PubMed

Clarke, Colin; Eales-Reynolds, Lesley-Jane

2015-01-01

The purpose of this paper is to examine if customer care (CC) can be directly linked to patient safety through a human factors (HF) framework. Data from an online questionnaire, completed by a convenience healthcare worker sample (n=373), was interrogated using thematic analysis within Vincent et al.'s (1998) HF theoretical framework. This proposes seven areas affecting patient safety: institutional context, organisation and management, work environment, team factors, individual, task and patient. Analysis identified responses addressing all framework areas. Responses (597) principally focused on work environment 40.7 per cent (n=243), organisation and management 28.8 per cent (n=172). Nevertheless, reference to other framework areas were clearly visible within the data: teams 10.2 per cent (n=61), individual 6.7 per cent (n=40), patients 6.0 per cent (n=36), tasks 4.2 per cent (n=24) and institution 3.5 per cent (n=21). Findings demonstrate congruence between CC perceptions and patient safety within a HF framework. The questionnaire requested participants to identify barriers to rather than CC enablers. Although this was at a single site complex organisation, it was similar to those throughout the NHS and other international health systems. CC can be viewed as consonant with patient safety rather than the potentially dangerous consumerisation stance, which could ultimately compromise patient safety. This work provides an original perspective on the link between CC and patient safety and has the potential to re-focus healthcare perceptions.

Testing the white dwarf mass-radius relationship with eclipsing binaries

NASA Astrophysics Data System (ADS)

Parsons, S. G.; Gänsicke, B. T.; Marsh, T. R.; Ashley, R. P.; Bours, M. C. P.; Breedt, E.; Burleigh, M. R.; Copperwheat, C. M.; Dhillon, V. S.; Green, M.; Hardy, L. K.; Hermes, J. J.; Irawati, P.; Kerry, P.; Littlefair, S. P.; McAllister, M. J.; Rattanasoon, S.; Rebassa-Mansergas, A.; Sahman, D. I.; Schreiber, M. R.

2017-10-01

We present high-precision, model-independent, mass and radius measurements for 16 white dwarfs in detached eclipsing binaries and combine these with previously published data to test the theoretical white dwarf mass-radius relationship. We reach a mean precision of 2.4 per cent in mass and 2.7 per cent in radius, with our best measurements reaching a precision of 0.3 per cent in mass and 0.5 per cent in radius. We find excellent agreement between the measured and predicted radii across a wide range of masses and temperatures. We also find the radii of all white dwarfs with masses less than 0.48 M⊙ to be fully consistent with helium core models, but they are on average 9 per cent larger than those of carbon-oxygen core models. In contrast, white dwarfs with masses larger than 0.52 M⊙ all have radii consistent with carbon-oxygen core models. Moreover, we find that all but one of the white dwarfs in our sample have radii consistent with possessing thick surface hydrogen envelopes (10-5 ≥ MH/MWD ≥ 10-4), implying that the surface hydrogen layers of these white dwarfs are not obviously affected by common envelope evolution.

STUDIES ON ISOLATED NUCLEI. I. ISOLATION AND CHEMICAL CHARACTERIZATION OF A NUCLEAR FRACTION FROM GUINEA PIG LIVER.

PubMed

MAGGIO, R; SIEKEVITZ, P; PALADE, G E

1963-08-01

This article describes a method for the isolation of nuclei from guinea pig liver. It involves the homogenization of the tissue in 0.88 M sucrose-1.5 mM CaCl(2) followed by centrifugation in a discontinuous density gradient in which the upper phase is the homogenate and the lower phase is 2.2 M sucrose-0.5 mM CaCl(2). Based on DNA recovery, the isolated fraction contains 25 to 30 per cent of the nuclei of the original homogenate. Electron microscopical observations showed that approximately 88 per cent of the isolated nuclei come from liver cells (the rest from von Kupffer cells and leucocytes) and that approximately 90 per cent of the nuclei appear intact, with well preserved nucleoli, nucleoplasm, nuclear envelope, and pores. Cytoplasmic contamination is minimal and consists primarily of the nuclear envelope and its attached ribosomes. The nuclear fraction consists of approximately 22.3 per cent DNA, approximately 4.7 per cent RNA, and approximately 73 per cent protein, the DNA/RNA ratio being 4.7. Data on RNA extractibility by phosphate and salt and on the base composition of total nuclear RNA are included.

Lithium-antimony-lead liquid metal battery for grid-level energy storage

NASA Astrophysics Data System (ADS)

Wang, Kangli; Jiang, Kai; Chung, Brice; Ouchi, Takanari; Burke, Paul J.; Boysen, Dane A.; Bradwell, David J.; Kim, Hojong; Muecke, Ulrich; Sadoway, Donald R.

2014-10-01

The ability to store energy on the electric grid would greatly improve its efficiency and reliability while enabling the integration of intermittent renewable energy technologies (such as wind and solar) into baseload supply. Batteries have long been considered strong candidate solutions owing to their small spatial footprint, mechanical simplicity and flexibility in siting. However, the barrier to widespread adoption of batteries is their high cost. Here we describe a lithium-antimony-lead liquid metal battery that potentially meets the performance specifications for stationary energy storage applications. This Li||Sb-Pb battery comprises a liquid lithium negative electrode, a molten salt electrolyte, and a liquid antimony-lead alloy positive electrode, which self-segregate by density into three distinct layers owing to the immiscibility of the contiguous salt and metal phases. The all-liquid construction confers the advantages of higher current density, longer cycle life and simpler manufacturing of large-scale storage systems (because no membranes or separators are involved) relative to those of conventional batteries. At charge-discharge current densities of 275 milliamperes per square centimetre, the cells cycled at 450 degrees Celsius with 98 per cent Coulombic efficiency and 73 per cent round-trip energy efficiency. To provide evidence of their high power capability, the cells were discharged and charged at current densities as high as 1,000 milliamperes per square centimetre. Measured capacity loss after operation for 1,800 hours (more than 450 charge-discharge cycles at 100 per cent depth of discharge) projects retention of over 85 per cent of initial capacity after ten years of daily cycling. Our results demonstrate that alloying a high-melting-point, high-voltage metal (antimony) with a low-melting-point, low-cost metal (lead) advantageously decreases the operating temperature while maintaining a high cell voltage. Apart from the fact that this finding puts us on a desirable cost trajectory, this approach may well be more broadly applicable to other battery chemistries.

Lithium-antimony-lead liquid metal battery for grid-level energy storage.

PubMed

Wang, Kangli; Jiang, Kai; Chung, Brice; Ouchi, Takanari; Burke, Paul J; Boysen, Dane A; Bradwell, David J; Kim, Hojong; Muecke, Ulrich; Sadoway, Donald R

2014-10-16

The ability to store energy on the electric grid would greatly improve its efficiency and reliability while enabling the integration of intermittent renewable energy technologies (such as wind and solar) into baseload supply. Batteries have long been considered strong candidate solutions owing to their small spatial footprint, mechanical simplicity and flexibility in siting. However, the barrier to widespread adoption of batteries is their high cost. Here we describe a lithium-antimony-lead liquid metal battery that potentially meets the performance specifications for stationary energy storage applications. This Li||Sb-Pb battery comprises a liquid lithium negative electrode, a molten salt electrolyte, and a liquid antimony-lead alloy positive electrode, which self-segregate by density into three distinct layers owing to the immiscibility of the contiguous salt and metal phases. The all-liquid construction confers the advantages of higher current density, longer cycle life and simpler manufacturing of large-scale storage systems (because no membranes or separators are involved) relative to those of conventional batteries. At charge-discharge current densities of 275 milliamperes per square centimetre, the cells cycled at 450 degrees Celsius with 98 per cent Coulombic efficiency and 73 per cent round-trip energy efficiency. To provide evidence of their high power capability, the cells were discharged and charged at current densities as high as 1,000 milliamperes per square centimetre. Measured capacity loss after operation for 1,800 hours (more than 450 charge-discharge cycles at 100 per cent depth of discharge) projects retention of over 85 per cent of initial capacity after ten years of daily cycling. Our results demonstrate that alloying a high-melting-point, high-voltage metal (antimony) with a low-melting-point, low-cost metal (lead) advantageously decreases the operating temperature while maintaining a high cell voltage. Apart from the fact that this finding puts us on a desirable cost trajectory, this approach may well be more broadly applicable to other battery chemistries.

Predicting structures in the Zone of Avoidance

NASA Astrophysics Data System (ADS)

Sorce, Jenny G.; Colless, Matthew; Kraan-Korteweg, Renée C.; Gottlöber, Stefan

2017-11-01

The Zone of Avoidance (ZOA), whose emptiness is an artefact of our Galaxy dust, has been challenging observers as well as theorists for many years. Multiple attempts have been made on the observational side to map this region in order to better understand the local flows. On the theoretical side, however, this region is often simply statistically populated with structures but no real attempt has been made to confront theoretical and observed matter distributions. This paper takes a step forward using constrained realizations (CRs) of the local Universe shown to be perfect substitutes of local Universe-like simulations for smoothed high-density peak studies. Far from generating completely `random' structures in the ZOA, the reconstruction technique arranges matter according to the surrounding environment of this region. More precisely, the mean distributions of structures in a series of constrained and random realizations (RRs) differ: while densities annihilate each other when averaging over 200 RRs, structures persist when summing 200 CRs. The probability distribution function of ZOA grid cells to be highly overdense is a Gaussian with a 15 per cent mean in the random case, while that of the constrained case exhibits large tails. This implies that areas with the largest probabilities host most likely a structure. Comparisons between these predictions and observations, like those of the Puppis 3 cluster, show a remarkable agreement and allow us to assert the presence of the, recently highlighted by observations, Vela supercluster at about 180 h-1 Mpc, right behind the thickest dust layers of our Galaxy.

H-, He-like recombination spectra - II. l-changing collisions for He Rydberg states

NASA Astrophysics Data System (ADS)

Guzmán, F.; Badnell, N. R.; Williams, R. J. R.; van Hoof, P. A. M.; Chatzikos, M.; Ferland, G. J.

2017-01-01

Cosmological models can be constrained by determining primordial abundances. Accurate predictions of the He I spectrum are needed to determine the primordial helium abundance to a precision of <1 per cent in order to constrain big bang nucleosynthesis models. Theoretical line emissivities at least this accurate are needed if this precision is to be achieved. In the first paper of this series, which focused on H I, we showed that differences in l-changing collisional rate coefficients predicted by three different theories can translate into 10 per cent changes in predictions for H I spectra. Here, we consider the more complicated case of He atoms, where low-l subshells are not energy degenerate. A criterion for deciding when the energy separation between l subshells is small enough to apply energy-degenerate collisional theories is given. Moreover, for certain conditions, the Bethe approximation originally proposed by Pengelly & Seaton is not sufficiently accurate. We introduce a simple modification of this theory which leads to rate coefficients which agree well with those obtained from pure quantal calculations using the approach of Vrinceanu et al. We show that the l-changing rate coefficients from the different theoretical approaches lead to differences of ˜10 per cent in He I emissivities in simulations of H II regions using spectral code CLOUDY.

Coxiella burnetii seroprevalence and risk factors on commercial sheep farms in The Netherlands.

PubMed

Schimmer, B; de Lange, M M A; Hautvast, J L A; Vellema, P; van Duynhoven, Y T H P

2014-07-05

Coxiella burnetii seroprevalence was assessed on Dutch dairy and non-dairy sheep farms using ELISA. Risk factors for seropositivity on non-dairy sheep farms were identified at farm and sheep level by univariate and multivariate multilevel analyses. Based on 953 dairy and 5671 non-dairy serum samples, sheep seroprevalences were 18.7 per cent and 2.0 per cent, respectively, and 78.6 per cent and 30.5 per cent at farm level. Significant risk factors for non-dairy sheep farms were farm location in the south of the country, sheep kept on marginal grounds, one or several supply addresses for ewes during 2007-2009 and wearing farm boots and/or outfit by professional visitors. On sheep level, risk factors included among others farm location in the south of the country, lamb breeding as main farm purpose, goat density within 10 km farm radius, use of windbreak curtain or windshields, and presence of ≥6 stillborn lambs in 2009. Farm location in the south of the country and goat density suggests that infected goats have played a role in the transmission to non-dairy sheep. Other risk factors suggest introduction of the bacterium through sheep supply and professional visitors. Biosecurity measures should be strengthened, including avoiding infection during handling of stillborn lambs and birth products in the lambing period. British Veterinary Association.

Factors affecting high-density lipoprotein cholesterol in HIV-infected patients on nevirapine-based antiretroviral therapy

PubMed Central

Padmapriyadarsini, C.; Ramesh, K.; Sekar, L.; Ramachandran, Geetha; Reddy, Devaraj; Narendran, G.; Sekar, S.; Chandrasekar, C.; Anbarasu, D.; Wanke, Christine; Swaminathan, Soumya

2017-01-01

Background & objectives: Cardiovascular disease (CVD) risk with low high-density lipoprotein cholesterol (HDL-C) and high triglycerides is common in the general population in India. As nevirapine (NVP)-based antiretroviral therapy (ART) tends to increase HDL-C, gene polymorphisms associated with HDL-C metabolism in HIV-infected adults on stable NVP-based ART were studied. Methods: A cross-sectional study was conducted between January 2013 and July 2014 among adults receiving NVP-based ART for 12-15 months. Blood lipids were estimated and gene polymorphisms in apolipoprotein C3 (APOC3), cholesteryl ester transfer protein (CETP) and lipoprotein lipase (LPL) genes were analyzed by real-time polymerase chain reaction. Framingham's 10-yr CVD risk score was estimated. Logistic regression was done to show factors related to low HDL-C levels. Results: Of the 300 patients included (mean age: 38.6±8.7 yr; mean CD4 count 449±210 cell/μl), total cholesterol (TC) >200 mg/dl was observed in 116 (39%) patients. Thirty nine per cent males and 47 per cent females had HDL-C levels below normal while 32 per cent males and 37 per cent females had TC/HDL ratio of 4.5 and 4.0, respectively. Body mass index [adjusted odds ratio (aOR)=1.70, 95% confidence interval (CI) 1.01-2.84, P=0.04] and viral load (aOR=3.39, 95% CI: 1.52-7.52, P=0.003) were negatively associated with serum HDL-C levels. The 10-yr risk score of developing CVD was 11-20 per cent in 3 per cent patients. Allelic variants of APOC3 showed a trend towards low HDL-C. Interpretation & conclusions: High-risk lipid profiles for atherosclerosis and cardiovascular disease were common among HIV-infected individuals, even after 12 months of NVP-based ART. Targeted interventions to address these factors should be recommended in the national ART programmes. PMID:28948955

Probing the structure of the gas in the Milky Way through X-ray high-resolution spectroscopy

NASA Astrophysics Data System (ADS)

Gatuzz, Efraín; Churazov, Eugene

2018-02-01

We have developed a new X-ray absorption model, called IONeq, which computes the optical depth τ(E) simultaneously for ions of all abundant elements, assuming ionization equilibrium and taking into account turbulent broadening. We use this model to analyse the interstellar medium (ISM) absorption features in the Milky Way for a sample of 18 Galactic (LMXBs) and 42 extragalactic sources (mainly Blazars). The absorbing ISM was modelled as a combination of three components/phases - neutral (T ≲ 1 × 104 K), warm (T ˜ 5 × 104 K) and hot (T ˜ 2 × 106 K). We found that the spatial distribution of both, neutral and warm components, are difficult to describe using smooth profiles due to non-uniform distribution of the column densities over the sky. For the hot phase we used a combination of a flattened disc and a halo, finding comparable column densities for both spatial components, of the order of ˜6-7 × 1018 cm-2, although this conclusion depends on the adopted parametrization. If the halo component has sub-solar abundance Z, then the column density has to be scaled up by a factor of Z_{⊙}/Z. The vertically integrated column densities of the disc components suggest the following mass fractions for these three ISM phases in the Galactic disc: neutral ˜ 89 per cent, warm ˜ 8 per cent and hot ˜ 3 per cent components, respectively. The constraints on the radial distribution of the halo component of the hot component are weak.

Method for applying pyrolytic carbon coatings to small particles

DOEpatents

Beatty, Ronald L.; Kiplinger, Dale V.; Chilcoat, Bill R.

1977-01-01

A method for coating small diameter, low density particles with pyrolytic carbon is provided by fluidizing a bed of particles wherein at least 50 per cent of the particles have a density and diameter of at least two times the remainder of the particles and thereafter recovering the small diameter and coated particles.

Dispersal, environmental niches and oceanic-scale turnover in deep-sea bivalves

PubMed Central

McClain, Craig R.; Stegen, James C.; Hurlbert, Allen H.

2012-01-01

Patterns of beta-diversity or distance decay at oceanic scales are completely unknown for deep-sea communities. Even when appropriate data exist, methodological problems have made it difficult to discern the relative roles of environmental filtering and dispersal limitation for generating faunal turnover patterns. Here, we combine a spatially extensive dataset on deep-sea bivalves with a model incorporating ecological dynamics and shared evolutionary history to quantify the effects of environmental filtering and dispersal limitation. Both the model and empirical data are used to relate functional, taxonomic and phylogenetic similarity between communities to environmental and spatial distances separating them for 270 sites across the Atlantic Ocean. This study represents the first ocean-wide analysis examining distance decay as a function of a broad suite of explanatory variables. We find that both strong environmental filtering and dispersal limitation drive turnover in taxonomic, functional and phylogenetic composition in deep-sea bivalves, explaining 26 per cent, 34 per cent and 9 per cent of the variation, respectively. This contrasts with previous suggestions that dispersal is not limiting in broad-scale biogeographic and biodiversity patterning in marine systems. However, rates of decay in similarity with environmental distance were eightfold to 44-fold steeper than with spatial distance. Energy availability is the most influential environmental variable evaluated, accounting for 3.9 per cent, 9.4 per cent and 22.3 per cent of the variation in functional, phylogenetic and taxonomic similarity, respectively. Comparing empirical patterns with process-based theoretical predictions provided quantitative estimates of dispersal limitation and niche breadth, indicating that 95 per cent of deep-sea bivalve propagules will be able to persist in environments that deviate from their optimum by up to 2.1 g m−2 yr−1 and typically disperse 749 km from their natal site. PMID:22189399

Impact of lambdacyhalothrin capsule suspension treated bed nets on malaria in tribal villages of Malkangiri district, Orissa, India.

PubMed

Sahu, S S; Vijayakumar, T; Kalyanasundaram, M; Subramanian, S; Jambulingam, P

2008-09-01

Insecticide treated mosquito nets are increasingly being used in malaria control programmes. One of the problems with the treatment of bed nets with conventional formulations of insecticides was that regular washing of treated nets diminish insecticidal effect. Lambdacyhalothrin 2.5 capsule suspension (CS) (2.5% a.i., w/v), a new water-based microencapsulated formulation is reported to have wash-resistant property and longer persistence on the netting material than other formulations. We evaluated the impact of the use of nylon bed nets treated with lambdacyhalothrin 2.5 CS at 10 mg (a.i.)/m(2) in comparison to untreated nets and no nets on malaria in tribal villages in Orissa. Nine foothill villages, highly endemic for falciparum malaria, from the Primary Health Centre (PHC) areas of Khairput and Kudumulugumma of Malkangiri district, Orissa, were divided into three groups, each with a population of about 500 and allocated randomly for treated (TN) and untreated nets (UN) and no nets (NN). Bed nets were distributed in September 2001 and retreatment was done in June 2002. The impact was assessed based on the changes in vector density, parous rate, malaria incidence and parasite rates. Indoor-resting collections of Anopheles fluviatilis and An. culicifacies were made at fortnightly intervals from fixed human dwellings. Mass blood surveys before and after distribution of nets and fortnightly active surveillance were carried out to assess the change in parasite rates and malaria incidence. Bioassays were conducted at fortnightly intervals on the bed nets supplied to the villagers. The reductions in indoor resting catches of An. fluviatilis and An. culicifacies were 96 and 38 per cent in villages with treated nets and 2.6 and 23 per cent in villages with untreated nets respectively compared to no net villages. For six months following treatment, 100 per cent mortality of An. fluviatilis was observed on the unwashed nets and on the nets washed once or twice. After re-treatment, 100 per cent mortality of An. fluviatilis or An. culicifacies was observed for nine months even after two washes. Usage rates of treated and untreated nets varied seasonally; 58.9 and 46.3 per cent in rainy season, 48.6 and 37.1 per cent in winter season and 38.1 and 31.6 per cent in summer season respectively. Reductions in malaria parasite rates were about 65 per cent in the treated net villages and 39 per cent in the untreated net villages compared to no net villages. About 75 per cent of treated nets and 60 per cent of untreated nets were in usable condition 19 months after distribution. The estimated protection factor based on malaria incidence was 86 per cent for the treated nets during both post-treatment and post-retreatment periods and 34 and 51 per cent for untreated nets for the corresponding periods compared to no nets. The results of the study showed that the use of bed nets treated nets with CS formulation of lambdacyhalothrin at 10 mg (a.i.)/m(2) was acceptable to the community and re-treatment of nets at nine-monthly intervals can significantly reduce density and survival of An. fluviatilis and incidence of falciparum malaria.

Molecular clumps in the W51 giant molecular cloud

NASA Astrophysics Data System (ADS)

Parsons, H.; Thompson, M. A.; Clark, J. S.; Chrysostomou, A.

2012-08-01

In this paper, we present a catalogue of dense molecular clumps located within the W51 giant molecular cloud (GMC). This work is based on Heterodyne Array Receiver Programme 13CO J = 3-2 observations of the W51 GMC and uses the automated CLUMPFIND algorithm to decompose the region into a total of 1575 clumps of which 1130 are associated with the W51 GMC. We clearly see the distinct structures of the W51 complex and the high-velocity stream previously reported. We find the clumps have characteristic diameters of 1.4 pc, excitation temperatures of 12 K, densities of 5.6 × 1021 cm-2, surface densities 0.02 g cm-2 and masses of 90 M⊙. We find a total mass of dense clumps within the GMC of 1.5 × 105 M⊙, with only 1 per cent of the clumps detected by number and 4 per cent by mass found to be supercritical. We find a clump-forming efficiency of 14 ± 1 per cent for the W51 GMC and a supercritical clump-forming efficiency of 0.5-0.5+2.3 per cent. Looking at the clump mass distribution, we find it is described by a single power law with a slope of α=2.4-0.1+0.2 above ˜100 M⊙. By comparing locations of supercritical clumps and young clusters, we see that any future star formation is likely to be located away from the currently active W51A region.

Imaginary-frequency polarizability and van der Waals force constants of two-electron atoms, with rigorous bounds

NASA Technical Reports Server (NTRS)

Glover, R. M.; Weinhold, F.

1977-01-01

Variational functionals of Braunn and Rebane (1972) for the imagery-frequency polarizability (IFP) have been generalized by the method of Gramian inequalities to give rigorous upper and lower bounds, valid even when the true (but unknown) unperturbed wavefunction must be represented by a variational approximation. Using these formulas in conjunction with flexible variational trial functions, tight error bounds are computed for the IFP and the associated two- and three-body van der Waals interaction constants of the ground 1(1S) and metastable 2(1,3S) states of He and Li(+). These bounds generally establish the ground-state properties to within a fraction of a per cent and metastable properties to within a few per cent, permitting a comparative assessment of competing theoretical methods at this level of accuracy. Unlike previous 'error bounds' for these properties, the present results have a completely a priori theoretical character, with no empirical input data.

The interstellar carbonaceous aromatic matter as a trap for molecular hydrogen

NASA Astrophysics Data System (ADS)

Pauzat, F.; Lattelais, M.; Ellinger, Y.; Minot, C.

2011-04-01

We report a theoretical study of the physisorption of molecular hydrogen, H2, on a major component of the interstellar dust, namely, the polyaromatic carbonaceous grains. Going beyond the model of the polycyclic aromatic hydrocarbon freeflyers and its theoretical treatment within the super molecule approach, we consider the graphene surface in a Density Functional Theory periodic approach using plane-wave expansions. The physisorption energy of isolated H2 on that flat and rigid support is determined to be attractive by ˜0.75 kcal mol-1 and practically independent of the orientation with respect to the infinite surface. Since this energy is also not affected by the position (over a ring centre, a carbon atom or the middle of a carbon-carbon bond), we can conclude that H2 is able to move freely like a ball rolling on the graphene support. We also investigate the conditions for multiple physisorption. It leads to a monolayer of H2 molecules where the corresponding interaction energy per H2 amounts to a potential depth of ˜1 kcal mol-1, close to the available experimental estimates ranging from 1.1 to 1.2 kcal mol-1. We show that the most energetically favourable coverage, which corresponds to an arrangement of the H2 molecules, the closest possible to the dimer configuration, leads to a surface density of ˜0.8 × 1015 molecule cm-2. Finally, assuming that 15-20 per cent of the interstellar carbon is locked in aromatic systems, one obtains ˜10-5 of the interstellar hydrogen trapped as H2 on such types of surfaces.

Warm-hot gas in X-ray bright galaxy clusters and the H I-deficient circumgalactic medium in dense environments

NASA Astrophysics Data System (ADS)

Burchett, Joseph N.; Tripp, Todd M.; Wang, Q. Daniel; Willmer, Christopher N. A.; Bowen, David V.; Jenkins, Edward B.

2018-04-01

We analyse the intracluster medium (ICM) and circumgalactic medium (CGM) in seven X-ray-detected galaxy clusters using spectra of background quasi-stellar objects (QSOs) (HST-COS/STIS), optical spectroscopy of the cluster galaxies (MMT/Hectospec and SDSS), and X-ray imaging/spectroscopy (XMM-Newton and Chandra). First, we report a very low covering fraction of H I absorption in the CGM of these cluster galaxies, f_c = 25^{+25}_{-15} {per cent}, to stringent detection limits (N(H I) <1013 cm-2). As field galaxies have an H I covering fraction of ˜ 100 per cent at similar radii, the dearth of CGM H I in our data indicates that the cluster environment has effectively stripped or overionized the gaseous haloes of these cluster galaxies. Secondly, we assess the contribution of warm-hot (105-106 K) gas to the ICM as traced by O VI and broad Ly α (BLA) absorption. Despite the high signal-to-noise ratio of our data, we do not detect O VI in any cluster, and we only detect BLA features in the QSO spectrum probing one cluster. We estimate that the total column density of warm-hot gas along this line of sight totals to ˜ 3 per cent of that contained in the hot T > 107 K X-ray emitting phase. Residing at high relative velocities, these features may trace pre-shocked material outside the cluster. Comparing gaseous galaxy haloes from the low-density `field' to galaxy groups and high-density clusters, we find that the CGM is progressively depleted of H I with increasing environmental density, and the CGM is most severely transformed in galaxy clusters. This CGM transformation may play a key role in environmental galaxy quenching.

Radiation-damped profiles of extremely high column density neutral hydrogen: implications of cosmic reionization

NASA Astrophysics Data System (ADS)

Bach, Kiehunn

2017-01-01

Incorporating the time-dependent second-order perturbation theory for the Lyman scattering cross-section, we investigate the intergalactic absorption profiles of extremely high column density systems near the end of cosmic reionization. Assuming a representative set of the redshift distribution of neutral hydrogen, we quantitatively examined the impact of inhomogeneous density on the intrinsic absorption profiles. The cumulative absorption by neutral patches in the line of sight mainly affects the far off-centre region of the red damping wing, but the effect is not significant. The shape of the line centre can be modified by the near-zone distribution due to high opacities of the near-resonance scattering. On the other hand, the HWHM (half width at half-maximum) as an effective line width is relatively less sensitive to the local inhomogeneity. Specifically, when the two local damping wings of Lyα and Lyβ are close in spectra of the strongly damped systems, accurate profiles of both lines are required. In the case of N_{H I}≲ 10^{21} { cm^{-2}}, the two-level approximation is marginally applicable for the damping wing fit within 5 - 7 per cent errors. However, as the local column density reaches N_{H I}˜ 10^{22.3} { cm^{-2}}, this classical approximation yields a relative error of a 10 per cent overestimation in the red wing and a 20 per cent underestimation in the blue wing of Lyα. If severe extinction by the Lyα forests is carefully subtracted, the intrinsic absorption profile will provide a better constraint on the local ionized states. For practical applications, an analytic fitting function for the Lyβ scattering is derived.

The impact of baryons on massive galaxy clusters: halo structure and cluster mass estimates

NASA Astrophysics Data System (ADS)

Henson, Monique A.; Barnes, David J.; Kay, Scott T.; McCarthy, Ian G.; Schaye, Joop

2017-03-01

We use the BAHAMAS (BAryons and HAloes of MAssive Systems) and MACSIS (MAssive ClusterS and Intercluster Structures) hydrodynamic simulations to quantify the impact of baryons on the mass distribution and dynamics of massive galaxy clusters, as well as the bias in X-ray and weak lensing mass estimates. These simulations use the subgrid physics models calibrated in the BAHAMAS project, which include feedback from both supernovae and active galactic nuclei. They form a cluster population covering almost two orders of magnitude in mass, with more than 3500 clusters with masses greater than 1014 M⊙ at z = 0. We start by characterizing the clusters in terms of their spin, shape and density profile, before considering the bias in both weak lensing and hydrostatic mass estimates. Whilst including baryonic effects leads to more spherical, centrally concentrated clusters, the median weak lensing mass bias is unaffected by the presence of baryons. In both the dark matter only and hydrodynamic simulations, the weak lensing measurements underestimate cluster masses by ≈10 per cent for clusters with M200 ≤ 1015 M⊙ and this bias tends to zero at higher masses. We also consider the hydrostatic bias when using both the true density and temperature profiles, and those derived from X-ray spectroscopy. When using spectroscopic temperatures and densities, the hydrostatic bias decreases as a function of mass, leading to a bias of ≈40 per cent for clusters with M500 ≥ 1015 M⊙. This is due to the presence of cooler gas in the cluster outskirts. Using mass weighted temperatures and the true density profile reduces this bias to 5-15 per cent.

The phase function and density of the dust observed at comet 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Fulle, Marco; Bertini, I.; Della Corte, V.; Güttler, C.; Ivanovski, S.; La Forgia, F.; Lasue, J.; Levasseur-Regourd, A. C.; Marzari, F.; Moreno, F.; Mottola, S.; Naletto, G.; Palumbo, P.; Rinaldi, G.; Rotundi, A.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Barucci, M. A.; Bertaux, J.-L.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Deller, J.; Fornasier, S.; Groussin, O.; Gutiérrez, P. J.; Hviid, H. S.; Ip, W. H.; Jorda, L.; Keller, H. U.; Knollenberg, J.; Kramm, J. R.; Kührt, E.; Küppers, M.; Lara, M. L.; Lazzarin, M.; López-Moreno, J. J.; Shi, X.; Thomas, N.; Tubiana, C.

2018-05-01

The OSIRIS camera onboard Rosetta measured the phase function of both the coma dust and the nucleus. The two functions have a very different slope versus the phase angle. Here, we show that the nucleus phase function should be adopted to convert the brightness to the size of dust particles larger than 2.5 mm only. This makes the dust bursts observed close to Rosetta by OSIRIS, occurring about every hour, consistent with the fragmentation on impact with Rosetta of parent particles, whose flux agrees with the dust flux observed by GIADA. OSIRIS also measured the antisunward acceleration of the fragments, thus providing the first direct measurement of the solar radiation force acting on the dust fragments and thus of their bulk density, excluding any measurable rocket effect by the ice sublimation from the dust. The obtained particle density distribution has a peak matching the bulk density of most COSIMA particles, and represents a subset of the density distribution measured by GIADA. This implies a bias in the elemental abundances measured by COSIMA, which thus are consistent with the 67P dust mass fractions inferred by GIADA, i.e. (38 ± 8) {per cent} of hydrocarbons versus the (62 ± 8) {per cent} of sulphides and silicates.

Tidal tomography constrains Earth's deep-mantle buoyancy.

PubMed

Lau, Harriet C P; Mitrovica, Jerry X; Davis, James L; Tromp, Jeroen; Yang, Hsin-Ying; Al-Attar, David

2017-11-15

Earth's body tide-also known as the solid Earth tide, the displacement of the solid Earth's surface caused by gravitational forces from the Moon and the Sun-is sensitive to the density of the two Large Low Shear Velocity Provinces (LLSVPs) beneath Africa and the Pacific. These massive regions extend approximately 1,000 kilometres upward from the base of the mantle and their buoyancy remains actively debated within the geophysical community. Here we use tidal tomography to constrain Earth's deep-mantle buoyancy derived from Global Positioning System (GPS)-based measurements of semi-diurnal body tide deformation. Using a probabilistic approach, we show that across the bottom two-thirds of the two LLSVPs the mean density is about 0.5 per cent higher than the average mantle density across this depth range (that is, its mean buoyancy is minus 0.5 per cent), although this anomaly may be concentrated towards the very base of the mantle. We conclude that the buoyancy of these structures is dominated by the enrichment of high-density chemical components, probably related to subducted oceanic plates or primordial material associated with Earth's formation. Because the dynamics of the mantle is driven by density variations, our result has important dynamical implications for the stability of the LLSVPs and the long-term evolution of the Earth system.

The inner mass power spectrum of galaxies using strong gravitational lensing: beyond linear approximation

NASA Astrophysics Data System (ADS)

Chatterjee, Saikat; Koopmans, Léon V. E.

2018-02-01

In the last decade, the detection of individual massive dark matter sub-haloes has been possible using potential correction formalism in strong gravitational lens imaging. Here, we propose a statistical formalism to relate strong gravitational lens surface brightness anomalies to the lens potential fluctuations arising from dark matter distribution in the lens galaxy. We consider these fluctuations as a Gaussian random field in addition to the unperturbed smooth lens model. This is very similar to weak lensing formalism and we show that in this way we can measure the power spectrum of these perturbations to the potential. We test the method by applying it to simulated mock lenses of different geometries and by performing an MCMC analysis of the theoretical power spectra. This method can measure density fluctuations in early type galaxies on scales of 1-10 kpc at typical rms levels of a per cent, using a single lens system observed with the Hubble Space Telescope with typical signal-to-noise ratios obtained in a single orbit.

CentNet—A deployable 100-station network for surface exchange research

NASA Astrophysics Data System (ADS)

Oncley, S.; Horst, T. W.; Semmer, S.; Militzer, J.; Maclean, G.; Knudson, K.

2014-12-01

Climate, air quality, atmospheric composition, surface hydrology, and ecological processes are directly affected by the Earth's surface. Complexity of this surface exists at multiple spatial scales, which complicates the understanding of these processes. NCAR/EOL currently provides a facility to the research community to make direct eddy-covariance flux observations to quantify surface-atmosphere interactions. However, just as model resolution has continued to increase, there is a need to increase the spatial density of flux measurements to capture the wide variety of scales that contribute to exchange processes close to the surface. NCAR/EOL now has developed the CentNet facility, that is envisioned to have on the order of 100 surface flux stations deployable for periods of months to years. Each station would measure standard meteorological variables, all components of the surface energy balance (including turbulence fluxes and radiation), atmospheric composition, and other quantities to characterize the surface. Thus, CentNet can support observational research in the biogeosciences, hydrology, urban meteorology, basic meteorology, and turbulence. CentNet has been designed to be adaptable to a wide variety of research problems while keeping operations manageable. Tower infrastructure has been designed to be lightweight, easily deployed, and with a minimal set-up footprint. CentNet uses sensor networks to increase spatial sampling at each station. The data system saves every sample on site to retain flexibility in data analysis. We welcome guidance on development and funding priorities as we build CentNet.

The second Herschel-ATLAS Data Release - III. Optical and near-infrared counterparts in the North Galactic Plane field

NASA Astrophysics Data System (ADS)

Furlanetto, C.; Dye, S.; Bourne, N.; Maddox, S.; Dunne, L.; Eales, S.; Valiante, E.; Smith, M. W.; Smith, D. J. B.; Ivison, R. J.; Ibar, E.

2018-05-01

This paper forms part of the second major public data release of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). In this work, we describe the identification of optical and near-infrared counterparts to the submillimetre detected sources in the 177 deg2 North Galactic Plane (NGP) field. We used the likelihood ratio method to identify counterparts in the Sloan Digital Sky Survey and in the United Kingdom InfraRed Telescope Imaging Deep Sky Survey within a search radius of 10 arcsec of the H-ATLAS sources with a 4σ detection at 250 μm. We obtained reliable (R ≥ 0.8) optical counterparts with r < 22.4 for 42 429 H-ATLAS sources (37.8 per cent), with an estimated completeness of 71.7 per cent and a false identification rate of 4.7 per cent. We also identified counterparts in the near-infrared using deeper K-band data which covers a smaller ˜25 deg2. We found reliable near-infrared counterparts to 61.8 per cent of the 250-μm-selected sources within that area. We assessed the performance of the likelihood ratio method to identify optical and near-infrared counterparts taking into account the depth and area of both input catalogues. Using catalogues with the same surface density of objects in the overlapping ˜25 deg2 area, we obtained that the reliable fraction in the near-infrared (54.8 per cent) is significantly higher than in the optical (36.4 per cent). Finally, using deep radio data which covers a small region of the NGP field, we found that 80-90 per cent of our reliable identifications are correct.

Solid state RF power: The route to 1W per euro cent

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

Heid, Oliver

2013-04-19

In most particle accelerators RF power is a decisive design constraint due to high costs and relative inflexibility of current electron beam based RF sources, i.e. Klystrons, Magnetrons, Tetrodes etc. At VHF/UHF frequencies the transition to solid state devices promises to fundamentally change the situation. Recent progress brings 1 Watt per Euro cent installed cost within reach. We present a Silicon Carbide semiconductor solution utilising the Solid State Direct Drive technology at unprecedented efficiency, power levels and power densities. The proposed solution allows retrofitting of existing RF accelerators and opens the route to novel particle accelerator concepts.

The properties and evolution of a K-band selected sample of massive galaxies at z ~ 0.4-2 in the Palomar/DEEP2 survey

NASA Astrophysics Data System (ADS)

Conselice, C. J.; Bundy, K.; Trujillo, I.; Coil, A.; Eisenhardt, P.; Ellis, R. S.; Georgakakis, A.; Huang, J.; Lotz, J.; Nandra, K.; Newman, J.; Papovich, C.; Weiner, B.; Willmer, C.

2007-11-01

We present the results of a study on the properties and evolution of massive (M* > 1011Msolar) galaxies at z ~ 0.4-2 utilizing Keck spectroscopy, near-infrared Palomar imaging, and Hubble, Chandra and Spitzer data covering fields targeted by the DEEP2 galaxy spectroscopic survey. Our sample is K-band selected and stellar mass limited, based on wide-area near-infrared imaging from the Palomar Observatory Wide-Field Infrared Survey, which covers 1.53 deg2 to a 5σ depth of Ks,vega ~ 20.5. Our primary goal is to obtain a broad census of massive galaxies through measuring how their number and mass densities, morphology, as well as their star formation and active galactic nucleus content evolve from z ~ 0.4-2. Our major findings include: (i) statistically the mass and number densities of M* > 1011Msolar galaxies show little evolution between z = 0 and 1 and from z ~ 0 to 2 for M* > 1011.5Msolar galaxies. We however find significant evolution within 1 < z < 1.5 for 1011 Msolar < M* < 1011.5Msolar galaxies. (ii) After examining the structures of our galaxies using Hubble ACS imaging, we find that M* > 1011Msolar selected galaxies show a nearly constant elliptical fraction of ~70-90 per cent at all redshifts. The remaining objects tend to be peculiars possibly undergoing mergers at z > 0.8, while spirals dominate the remainder at lower redshifts. A significant fraction (~25 per cent) of these early-types contain minor structural anomalies. (iii) We find that only a fraction (~60 per cent) of massive galaxies with M* > 1011Msolar are on the red sequence at z ~ 1.4, while nearly 100 per cent evolve on to it by z ~ 0.4. (iv) By utilizing Spitzer MIPS imaging and [OII] line fluxes we argue that M* > 1011.5Msolar galaxies have a steeply declining star formation rate (SFR) density ~ (1 + z)6. By examining the contribution of star formation to the evolution of the mass function, as well as the merger history through the CAS parameters, we determine that M* > 1011Msolar galaxies undergo on average 0.9+0.7-0.5 major mergers at 0.4 < z < 1.4. (v) We find that a high (5 per cent) fraction of all M* > 1011Msolar galaxies are X-ray emitters. Roughly half of these are morphologically distorted ellipticals or peculiars. Finally, we compare our mass growth with semi-analytical models from the Millennium Simulation, finding relative good agreement at z < 2 for the M* < 1011.5Msolar systems, but that the number and mass densities of M* > 1011.5Msolar galaxies are underpredicted by a factor of >100.

T-RaMiSu: the Two-meter Radio Mini Survey. I. The Boötes Field

NASA Astrophysics Data System (ADS)

Williams, W. L.; Intema, H. T.; Röttgering, H. J. A.

2013-01-01

We present wide area, deep, high-resolution 153 MHz GMRT observations of the NOAO Boötes field, adding to the extensive, multi-wavelength data of this region. The observations, data reduction, and catalogue construction and description are described here. The seven pointings produced a final mosaic covering 30 square degrees with a resolution of 25″. The rms noise is 2 mJy beam-1 in the centre of the image, rising to 4-5 mJy beam-1 on the edges, with an average of 3 mJy beam-1. Seventy-five per cent of the area has an rms <4 mJy beam-1. The extracted source catalogue contains 1289 sources detected at 5σ, of which 453 are resolved. We estimate the catalogue to be 92 per cent reliable and 95 per cent complete at an integrated flux density limit of 14 mJy. The flux densities and astrometry have been corrected for systematic errors. We calculate the differential source counts, which are in good agreement with those in the literature and provide an important step forward in quantifying the source counts at these low frequencies and low flux densities. The GMRT 153 MHz sources have been matched to the 1.4 GHz NVSS and 327 MHz WENSS catalogues and spectral indices were derived. Table A.1 (Catalogue) is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/549/A55

Warm-hot baryons comprise 5-10 per cent of filaments in the cosmic web.

PubMed

Eckert, Dominique; Jauzac, Mathilde; Shan, HuanYuan; Kneib, Jean-Paul; Erben, Thomas; Israel, Holger; Jullo, Eric; Klein, Matthias; Massey, Richard; Richard, Johan; Tchernin, Céline

2015-12-03

Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe's total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter density is larger than average) as a low-density plasma at temperatures of 10(5)-10(7) kelvin, known as the warm-hot intergalactic medium. There have been previous claims of the detection of warm-hot baryons along the line of sight to distant blazars and of hot gas between interacting clusters. These observations were, however, unable to trace the large-scale filamentary structure, or to estimate the total amount of warm-hot baryons in a representative volume of the Universe. Here we report X-ray observations of filamentary structures of gas at 10(7) kelvin associated with the galaxy cluster Abell 2744. Previous observations of this cluster were unable to resolve and remove coincidental X-ray point sources. After subtracting these, we find hot gas structures that are coherent over scales of 8 megaparsecs. The filaments coincide with over-densities of galaxies and dark matter, with 5-10 per cent of their mass in baryonic gas. This gas has been heated up by the cluster's gravitational pull and is now feeding its core. Our findings strengthen evidence for a picture of the Universe in which a large fraction of the missing baryons reside in the filaments of the cosmic web.

A 20 GHz bright sample for δ > 72° - II. Multifrequency follow-up

NASA Astrophysics Data System (ADS)

Ricci, R.; Righini, S.; Verma, R.; Prandoni, I.; Carretti, E.; Mack, K.-H.; Massardi, M.; Procopio, P.; Zanichelli, A.; Gregorini, L.; Mantovani, F.; Gawroński, M. P.; Peel, M. W.

2013-11-01

We present follow-up observations at 5, 8 and 30 GHz of the K-band Northern Wide Survey (KNoWS) 20 GHz Bright Sample, performed with the 32-m Medicina radio telescope and the 32-m Toruń radio telescope. The KNoWS sources were selected in the Northern Polar Cap (δ > 72°) and have a flux density limit S20 GHz = 115 mJy. We include NRAO-VLA Sky Survey 1.4 GHz measurements to derive the source radio spectra between 1.4 and 30 GHz. Based on optical identifications, 68 per cent of the sources are quasars and 27 per cent are radio galaxies. A redshift measurement is available for 58 per cent of the sources. The radio spectral properties of the different source populations are found to be in agreement with those of other high-frequency-selected samples.

Vascular surgical society of great britain and ireland: immunoglobulin A antibodies against chlamydia pneumoniae are associated with expansion of small abdominal aortic aneurysms and declining ankle blood pressure

PubMed

Lindholt; Vammen; Henneberg; Fasting

1999-05-01

BACKGROUND: The potential correlation between chronic infection with Chlamydia pneumoniae and the progression of small abdominal aortic aneurysms (AAAs) and lower limb atherosclerosis was studied. METHODS: Mass screening for AAA was carried out in outdoor clinics at all hospitals in the county. Some 139 men (aged 65-73 years) with a 3.0-4.9-cm AAA were followed prospectively for 1-3 (mean 2.7) years. Initially, an interview and examination was performed, and blood samples were taken. RESULTS: Some 62 per cent (53-71 per cent) had an immunoglobulin (Ig) A level of 40 or more, or an IgG level of 64 or above. Some 83 per cent (74-93 per cent) had an IgA level of 20 or more, or an IgG level of 32 or more. Men with an IgA level of 20 or more had 51 per cent greater AAA expansion and men with an IgA level of 40 or above had 24 per cent more expansion. An IgA level of 20 or more, or IgA of 40 or greater, were significant independent predictors of AAA expansion adjusted for age, smoking, initial AAA size, steroid treatment, diastolic blood pressure, pulmonary function and other plasma factors. The ankle blood pressure index (ABI) of the IgA-seropositive men decreased 11 per cent, while the ABI decreased by 5 per cent among IgA-seronegative men (P < 0.05). The significant difference persisted after adjusting for age, smoking, initial systolic ankle blood pressure, initial brachial systolic or diastolic blood pressure, but disappeared after adjusting for low-density lipoprotein (LDL) levels. CONCLUSION: A high proportion of men with a small AAA have signs of chronic C. pneumoniae infection. The progression of AAAs and lower limb atherosclerosis seems to be correlated to chronic infection with C. pneumoniae.

Abell 1367: a high fraction of late-type galaxies displaying H I morphological and kinematic perturbations

NASA Astrophysics Data System (ADS)

Scott, T. C.; Brinks, E.; Cortese, L.; Boselli, A.; Bravo-Alfaro, H.

2018-04-01

To investigate the effects the cluster environment has on late-type galaxies (LTGs), we studied H I perturbation signatures for all Abell 1367 LTGs with H I detections. We used new Very Large Array H I observations combined with AGES single-dish blind survey data. Our study indicates that the asymmetry between the high- and low-velocity wings of the characteristic double-horn-integrated H I spectrum as measured by the asymmetry parameter, A_{flux}, can be a useful diagnostic for ongoing and/or recent H I stripping. 26 per cent of A1367 LTGs have an A_{flux} ratio, more asymmetrical than 3 times the 1σ spread in the A_{flux} ratio distribution of an undisturbed sample of isolated galaxies (2 per cent) and samples from other denser environments (10 per cent-20 per cent). Over half of the A1367 LTGs, which are members of groups or pairs, have an A_{flux} ratio larger than twice the 1σ spread found in the isolated sample. This suggests intergroup/pair interactions could be making a significant contribution to the LTGs displaying such A_{flux} ratios. The study also demonstrates that the definition of the H I offset from the optical centre of LTGs is resolution dependent, suggesting that unresolved AGES H I offsets that are significantly larger than the pointing uncertainties (>2σ), reflect interactions which have asymmetrically displaced, significant masses of lower density H I, while having minimal impact on the location of the highest density H I in resolved maps. The distribution of A_{flux} from a comparable sample of Virgo galaxies provides a clear indication that the frequency of H I profile perturbations is lower than in A1367.

GALAPAGOS-C: analysis of galaxy morphologies using high-performance computing methods

NASA Astrophysics Data System (ADS)

Hiemer, Andreas; Barden, Marco; Kelvin, Lee S.; Häußler, Boris; Schindler, Sabine

2014-11-01

We present GALAPAGOS-C, a code designed to process a complete set of survey images through automation of source detection (via SEXTRACTOR), postage stamp cutting, object mask preparation, sky background estimation and complex two-dimensional light profile Sérsic modelling (via GALFIT). GALAPAGOS-C is designed around the concept of MPI-parallelization, allowing the processing of large data sets in a quick and efficient manner. Further, GALAPAGOS-C is capable of fitting multiple-Sérsic profiles to each galaxy, each representing distinct galaxy components (e.g. bulge, disc, bar), in addition to the option to fit asymmetric Fourier mode distortions. The modelling reliability of our core single-Sérsic fitting capability is tested thoroughly using image simulations. We apply GALAPAGOS-C to the Space Telescope A901/902 Galaxy Evolution Survey to investigate the evolution of galaxy structure with cosmic time and the dependence on environment. We measure the distribution of Sérsic indices as a function of local object density in the A901/902 cluster sample to provide one of the first measures of the Sérsic index-density relation. We find that the fraction of galaxies with a high Sérsic index (2.5 < n < 7.0) is higher in denser environments (˜35 per cent), halving towards sparsely populated regions (˜15 per cent). The population of low Sérsic index galaxies (0.4 < n< 1.6) is lower in denser environments (˜35 per cent), increasing towards sparsely populated regions (˜60 per cent). The population of intermediate Sérsic index galaxies (1.6 < n < 2.5) approximately follows the trend of the high Sérsic index types.

Performance of B. M. W. 185-Horsepower Airplane Engine

NASA Technical Reports Server (NTRS)

Sparrow, S W

1923-01-01

This report deals with the results of a test made upon a B. M. W. Engine in the altitude chamber of the Bureau of Standards, where controlled conditions of temperature and pressure can be made to simulate those of the desired altitude. A remarkably low value of fuel consumption - 041 per B. H. P. hour - is obtained at 1,200 revolutions per minute at an air density of 0.064 pound per cubic foot and a brake thermal efficiency of 33 per cent and an indicated efficiency of 37 per cent at the above speed and density. In spite of the fact that the carburetor adjustment does not permit the air-fuel ratio of maximum economy to be obtained at air densities lower than 0.064, the economy is superior to most engines tested thus far, even at a density lower than 0.064, the economies superior to most engines tested thus far, even at a density (0.03) corresponding to an altitude of 25,000 feet. The brake mean effective pressure even at full throttle is rather low. Since the weight of much of the engine is governed more by its piston displacement than by the power developed, a decreased mean effective pressure usually necessitates increased weight per horsepower. The altitude performance of the engine is, in general, excellent, and its low fuel consumption is the outstanding feature of merit.

Introducing galactic structure finder: the multiple stellar kinematic structures of a simulated Milky Way mass galaxy

NASA Astrophysics Data System (ADS)

Obreja, Aura; Macciò, Andrea V.; Moster, Benjamin; Dutton, Aaron A.; Buck, Tobias; Stinson, Gregory S.; Wang, Liang

2018-07-01

We present the first results of applying Gaussian Mixture Models in the stellar kinematic space of normalized angular momentum and binding energy on NIHAO high-resolution galaxies to separate the stars into multiple components. We exemplify this method, using a simulated Milky Way analogue, whose stellar component hosts thin and thick discs, classical and pseudo bulges, and a stellar halo. The properties of these stellar structures are in good agreement with observational expectations in terms of sizes, shapes, and rotational support. Interestingly, the two kinematic discs show surface mass density profiles more centrally concentrated than exponentials, while the bulges and the stellar halo are purely exponential. We trace back in time the Lagrangian mass of each component separately to study their formation history. Between z ˜ 3 and the end of halo virialization, z ˜ 1.3, all components lose a fraction of their angular momentum. The classical bulge loses the most (˜ 95 per cent) and the thin disc the least (˜ 60 per cent). Both bulges formed their stars in situ at high redshift, while the thin disc formed ˜ 98 per cent in situ, but with a constant SFR ˜ 1.5 M⊙ yr-1 over the last ˜11 Gyr. Accreted stars (6 per cent of total stellar mass) are mainly incorporated to the thick disc or the stellar halo, which formed ex situ 8 per cent and 45 per cent of their respective masses. Our analysis pipeline is freely available at https://github.com/aobr/gsf.

Trained in Science-Base Field: Change of Specialization among Educated Women in Malaysia

ERIC Educational Resources Information Center

Amin, Suhaida Mohd; Satar, Nurulhuda Mohd; Yap, Su Fei

2015-01-01

The theoretical model for economic development states that development in science and technology is the key to increased productivity. Upon realizing this, the Malaysian government has targeted 60 to 40 per cent of students for Science to Arts field at the tertiary level of education. However the rate of participation in science-based programs…

Abundant molecular oxygen in the coma of comet 67P/Churyumov-Gerasimenko.

PubMed

Bieler, A; Altwegg, K; Balsiger, H; Bar-Nun, A; Berthelier, J-J; Bochsler, P; Briois, C; Calmonte, U; Combi, M; De Keyser, J; van Dishoeck, E F; Fiethe, B; Fuselier, S A; Gasc, S; Gombosi, T I; Hansen, K C; Hässig, M; Jäckel, A; Kopp, E; Korth, A; Le Roy, L; Mall, U; Maggiolo, R; Marty, B; Mousis, O; Owen, T; Rème, H; Rubin, M; Sémon, T; Tzou, C-Y; Waite, J H; Walsh, C; Wurz, P

2015-10-29

The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov-Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet's formation, which is unexpected given the low upper limits from remote sensing observations. Current Solar System formation models do not predict conditions that would allow this to occur.

Quasar outflows at z ≥ 6: the impact on the host galaxies

NASA Astrophysics Data System (ADS)

Barai, Paramita; Gallerani, Simona; Pallottini, Andrea; Ferrara, Andrea; Marconi, Alessandro; Cicone, Claudia; Maiolino, Roberto; Carniani, Stefano

2018-01-01

We investigate quasar outflows at z ≥ 6 by performing zoom-in cosmological hydrodynamical simulations. By employing the smoothed particle hydrodynamics code GADGET-3, we zoom in the 2R200 region around a 2 × 1012 M⊙ halo at z = 6, inside a (500 Mpc)3 comoving volume. We compare the results of our active galactic nuclei (AGN) runs with a control simulation in which only stellar/SN feedback is considered. Seeding 105 M⊙ black holes (BHs) at the centres of 109 M⊙ haloes, we find the following results. BHs accrete gas at the Eddington rate over z = 9-6. At z = 6, our most-massive BH has grown to MBH = 4 × 109 M⊙. Fast (vr > 1000 km s-1), powerful (\\dot{M}_out ˜ 2000 M_{⊙} yr-1) outflows of shock-heated low-density gas form at z ∼ 7, and propagate up to hundreds kpc. Star formation is quenched over z = 8-6, and the total star formation rate (SFR surface density near the galaxy centre) is reduced by a factor of 5 (1000). We analyse the relative contribution of multiple physical process: (i) disrupting cosmic filamentary cold gas inflows, (ii) reducing central gas density, (iii) ejecting gas outside the galaxy; and find that AGN feedback has the following effects at z = 6. The inflowing gas mass fraction is reduced by ∼ 12 per cent, the high-density gas fraction is lowered by ∼ 13 per cent, and ∼ 20 per cent of the gas outflows at a speed larger than the escape velocity (500 km s-1). We conclude that quasar-host galaxies at z ≥ 6 are accreting non-negligible amount of cosmic gas, nevertheless AGN feedback quenches their star formation dominantly by powerful outflows ejecting gas out of the host galaxy halo.

A hydrostatic weighing method using total lung capacity and a small tank.

PubMed Central

Warner, J G; Yeater, R; Sherwood, L; Weber, K

1986-01-01

The purpose of this study was to establish the validity and reliability of a hydrostatic weighing method using total lung capacity (measuring vital capacity with a respirometer at the time of weighing) the prone position, and a small oblong tank. The validity of the method was established by comparing the TLC prone (tank) method against three hydrostatic weighing methods administered in a pool. The three methods included residual volume seated, TLC seated and TLC prone. Eighty male and female subjects were underwater weighed using each of the four methods. Validity coefficients for per cent body fat between the TLC prone (tank) method and the RV seated (pool), TLC seated (pool) and TLC prone (pool) methods were .98, .99 and .99, respectively. A randomised complete block ANOVA found significant differences between the RV seated (pool) method and each of the three TLC methods with respect to both body density and per cent body fat. The differences were negligible with respect to HW error. Reliability of the TLC prone (tank) method was established by weighing twenty subjects three different times with ten-minute time intervals between testing. Multiple correlations yielded reliability coefficients for body density and per cent body fat values of .99 and .99, respectively. It was concluded that the TLC prone (tank) method is valid, reliable and a favourable method of hydrostatic weighing. PMID:3697596

A hydrostatic weighing method using total lung capacity and a small tank.

PubMed

Warner, J G; Yeater, R; Sherwood, L; Weber, K

1986-03-01

The purpose of this study was to establish the validity and reliability of a hydrostatic weighing method using total lung capacity (measuring vital capacity with a respirometer at the time of weighing) the prone position, and a small oblong tank. The validity of the method was established by comparing the TLC prone (tank) method against three hydrostatic weighing methods administered in a pool. The three methods included residual volume seated, TLC seated and TLC prone. Eighty male and female subjects were underwater weighed using each of the four methods. Validity coefficients for per cent body fat between the TLC prone (tank) method and the RV seated (pool), TLC seated (pool) and TLC prone (pool) methods were .98, .99 and .99, respectively. A randomised complete block ANOVA found significant differences between the RV seated (pool) method and each of the three TLC methods with respect to both body density and per cent body fat. The differences were negligible with respect to HW error. Reliability of the TLC prone (tank) method was established by weighing twenty subjects three different times with ten-minute time intervals between testing. Multiple correlations yielded reliability coefficients for body density and per cent body fat values of .99 and .99, respectively. It was concluded that the TLC prone (tank) method is valid, reliable and a favourable method of hydrostatic weighing.

Mid-infrared luminous quasars in the GOODS-Herschel fields: a large population of heavily obscured, Compton-thick quasars at z ≈ 2

NASA Astrophysics Data System (ADS)

Del Moro, A.; Alexander, D. M.; Bauer, F. E.; Daddi, E.; Kocevski, D. D.; McIntosh, D. H.; Stanley, F.; Brandt, W. N.; Elbaz, D.; Harrison, C. M.; Luo, B.; Mullaney, J. R.; Xue, Y. Q.

2016-02-01

We present the infrared (IR) and X-ray properties of a sample of 33 mid-IR luminous quasars (νL6 μm ≥ 6 × 1044 erg s-1) at redshift z ≈ 1-3, identified through detailed spectral energy distribution analyses of distant star-forming galaxies, using the deepest IR data from Spitzer and Herschel in the GOODS-Herschel fields. The aim is to constrain the fraction of obscured, and Compton-thick (CT, NH > 1.5 × 1024 cm-2) quasars at the peak era of nuclear and star formation activities. Despite being very bright in the mid-IR band, ≈30 per cent of these quasars are not detected in the extremely deep 2 and 4 Ms Chandra X-ray data available in these fields. X-ray spectral analysis of the detected sources reveals that the majority (≈67 per cent) are obscured by column densities NH > 1022 cm-2; this fraction reaches ≈80 per cent when including the X-ray-undetected sources (9 out of 33), which are likely to be the most heavily obscured, CT quasars. We constrain the fraction of CT quasars in our sample to be ≈24-48 per cent, and their space density to be Φ = (6.7 ± 2.2) × 10-6 Mpc-3. From the investigation of the quasar host galaxies in terms of star formation rates (SFRs) and morphological distortions, as a sign of galaxy mergers/interactions, we do not find any direct relation between SFRs and quasar luminosity or X-ray obscuration. On the other hand, there is tentative evidence that the most heavily obscured quasars have, on average, more disturbed morphologies than the unobscured/moderately obscured quasar hosts, which preferentially live in undisturbed systems. However, the fraction of quasars with disturbed morphology amongst the whole sample is ≈40 per cent, suggesting that galaxy mergers are not the main fuelling mechanism of quasars at z ≈ 2.

Theoretical Basis for Anomalous Heat and ^4He in Deuterium-Metal Systems

NASA Astrophysics Data System (ADS)

Chubb, Scott; Chubb, Talbot

2000-03-01

Because electromagnetic (E.M.) forces have infinite range, reactions exist in which the degrees of freedom associated with nuclear- and atomic- scales are coupled. Although such non-separable reactions are possible in conventional D+D fusion, they rarely occur because the relevant E.M.-induced reaction (D+Darrow ^4He) violates the rules of energy-momentum conservation (EMC) at-a-point, except when a high momentum (HM) gamma ray is emitted. When D^+ and ^4He^+^+ occupy ion band states with low concentration, however, different forms of E.M. coupling become possible in which EMC is violated locally but conserved globally and D+Darrow ^4He reactions occur without HM particles(http: //www.aps.org/meet/CENT99/BAPS/abs/S9500.html). Using a generalized KKR-Multiple-Scattering theory, we have formulated Generalized Kadanoff-Baym Equations ( D.C. Langreth and J.W. Wilkins, Phys. Rev. B 6), 3189 (1972). that describe the associated non-local heat and ^4He release from the resulting coupling between nuclear interactions, D^+ and ^4He^+^+ ion band states, and electrons.

The Nature, Significance, and Evaluation of the Schwarzschild-Villiger (SV) Effect in Photometric Procedures

PubMed Central

Howling, D. H.; Fitzgerald, P. J.

1959-01-01

The Schwarzschild-Villiger effect has been experimentally demonstrated with the optical system used in this laboratory. Using a photographic mosaic specimen as a model, it has been shown that the conclusions of Naora are substantiated and that the SV effect, in large or small magnitude, is always present in optical systems. The theoretical transmission error arising from the presence of the SV effect has been derived for various optical conditions of measurement. The results have been experimentally confirmed. The SV contribution of the substage optics of microspectrophotometers has also been considered. A simple method of evaluating a flare function f(A) is advanced which provides a measure of the SV error present in a system. It is demonstrated that measurements of specimens of optical density less than unity can be made with less than 1 per cent error, when using illuminating beam diameter/specimen diameter ratios of unity and uncoated optical surfaces. For denser specimens it is shown that care must be taken to reduce the illuminating beam/specimen diameter ratio to a value dictated by the magnitude of a flare function f(A), evaluated for a particular optical system, in order to avoid excessive transmission error. It is emphasized that observed densities (transmissions) are not necessarily true densities (transmissions) because of the possibility of SV error. The ambiguity associated with an estimation of stray-light error by means of an opaque object has also been demonstrated. The errors illustrated are not necessarily restricted to microspectrophotometry but may possibly be found in such fields as spectral analysis, the interpretation of x-ray diffraction patterns, the determination of ionizing particle tracks and particle densities in photographic emulsions, and in many other types of photometric analysis. PMID:14403512

The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmic flows and cosmic web from luminous red galaxies

NASA Astrophysics Data System (ADS)

Ata, Metin; Kitaura, Francisco-Shu; Chuang, Chia-Hsun; Rodríguez-Torres, Sergio; Angulo, Raul E.; Ferraro, Simone; Gil-Marín, Hector; McDonald, Patrick; Hernández Monteagudo, Carlos; Müller, Volker; Yepes, Gustavo; Autefage, Mathieu; Baumgarten, Falk; Beutler, Florian; Brownstein, Joel R.; Burden, Angela; Eisenstein, Daniel J.; Guo, Hong; Ho, Shirley; McBride, Cameron; Neyrinck, Mark; Olmstead, Matthew D.; Padmanabhan, Nikhil; Percival, Will J.; Prada, Francisco; Rossi, Graziano; Sánchez, Ariel G.; Schlegel, David; Schneider, Donald P.; Seo, Hee-Jong; Streblyanska, Alina; Tinker, Jeremy; Tojeiro, Rita; Vargas-Magana, Mariana

2017-06-01

We present a Bayesian phase-space reconstruction of the cosmic large-scale matter density and velocity fields from the Sloan Digital Sky Survey-III Baryon Oscillations Spectroscopic Survey Data Release 12 CMASS galaxy clustering catalogue. We rely on a given Λ cold dark matter cosmology, a mesh resolution in the range of 6-10 h-1 Mpc, and a lognormal-Poisson model with a redshift-dependent non-linear bias. The bias parameters are derived from the data and a general renormalized perturbation theory approach. We use combined Gibbs and Hamiltonian sampling, implemented in the argo code, to iteratively reconstruct the dark matter density field and the coherent peculiar velocities of individual galaxies, correcting hereby for coherent redshift space distortions. Our tests relying on accurate N-body-based mock galaxy catalogues show unbiased real space power spectra of the non-linear density field up to k ˜ 0.2 h Mpc-1, and vanishing quadrupoles down to r ˜ 20 h-1 Mpc. We also demonstrate that the non-linear cosmic web can be obtained from the tidal field tensor based on the Gaussian component of the reconstructed density field. We find that the reconstructed velocities have a statistical correlation coefficient compared to the true velocities of each individual light-cone mock galaxy of r ˜ 0.68 including about 10 per cent of satellite galaxies with virial motions (about r = 0.75 without satellites). The power spectra of the velocity divergence agree well with theoretical predictions up to k ˜ 0.2 h Mpc-1. This work will be especially useful to improve, for example, baryon acoustic oscillation reconstructions, kinematic Sunyaev-Zeldovich, integrated Sachs-Wolfe measurements or environmental studies.

High performance, high density hydrocarbon fuels

NASA Technical Reports Server (NTRS)

Frankenfeld, J. W.; Hastings, T. W.; Lieberman, M.; Taylor, W. F.

1978-01-01

The fuels were selected from 77 original candidates on the basis of estimated merit index and cost effectiveness. The ten candidates consisted of 3 pure compounds, 4 chemical plant streams and 3 refinery streams. Critical physical and chemical properties of the candidate fuels were measured including heat of combustion, density, and viscosity as a function of temperature, freezing points, vapor pressure, boiling point, thermal stability. The best all around candidate was found to be a chemical plant olefin stream rich in dicyclopentadiene. This material has a high merit index and is available at low cost. Possible problem areas were identified as low temperature flow properties and thermal stability. An economic analysis was carried out to determine the production costs of top candidates. The chemical plant and refinery streams were all less than 44 cent/kg while the pure compounds were greater than 44 cent/kg. A literature survey was conducted on the state of the art of advanced hydrocarbon fuel technology as applied to high energy propellents. Several areas for additional research were identified.

An Earth-sized planet with an Earth-like density.

PubMed

Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

2013-11-21

Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

Testing the hierarchical assembly of massive galaxies using accurate merger rates out to z ˜ 1.5

NASA Astrophysics Data System (ADS)

Rodrigues, Myriam; Puech, M.; Flores, H.; Hammer, F.; Pirzkal, N.

2018-04-01

We established an accurate comparison between observationally and theoretically estimated major merger rates over a large range of mass (log Mbar/M⊙ =9.9-11.4) and redshift (z = 0.7-1.6). For this, we combined a new estimate of the merger rate from an exhaustive count of pairs within the virial radius of massive galaxies at z ˜ 1.265 and cross-validated with their morphology, with estimates from the morpho-kinematic analysis of two other samples. Theoretical predictions were estimated using semi-empirical models with inputs matching the properties of the observed samples, while specific visibility time-scales scaled to the observed samples were used. Both theory and observations are found to agree within 30 per cent of the observed value, which provides strong support to the hierarchical assembly of galaxies over the probed ranges of mass and redshift. Here, we find that ˜60 per cent of population of local massive (Mstellar =1010.3-11.6 M⊙) galaxies would have undergone a wet major merger since z = 1.5, consistently with previous studies. Such recent mergers are expected to result in the (re-)formation of a significant fraction of local disc galaxies.

Brittle intermetallic compound makes ultrastrong low-density steel with large ductility.

PubMed

Kim, Sang-Heon; Kim, Hansoo; Kim, Nack J

2015-02-05

Although steel has been the workhorse of the automotive industry since the 1920s, the share by weight of steel and iron in an average light vehicle is now gradually decreasing, from 68.1 per cent in 1995 to 60.1 per cent in 2011 (refs 1, 2). This has been driven by the low strength-to-weight ratio (specific strength) of iron and steel, and the desire to improve such mechanical properties with other materials. Recently, high-aluminium low-density steels have been actively studied as a means of increasing the specific strength of an alloy by reducing its density. But with increasing aluminium content a problem is encountered: brittle intermetallic compounds can form in the resulting alloys, leading to poor ductility. Here we show that an FeAl-type brittle but hard intermetallic compound (B2) can be effectively used as a strengthening second phase in high-aluminium low-density steel, while alleviating its harmful effect on ductility by controlling its morphology and dispersion. The specific tensile strength and ductility of the developed steel improve on those of the lightest and strongest metallic materials known, titanium alloys. We found that alloying of nickel catalyses the precipitation of nanometre-sized B2 particles in the face-centred cubic matrix of high-aluminium low-density steel during heat treatment of cold-rolled sheet steel. Our results demonstrate how intermetallic compounds can be harnessed in the alloy design of lightweight steels for structural applications and others.

HICOSMO: cosmology with a complete sample of galaxy clusters - II. Cosmological results

NASA Astrophysics Data System (ADS)

Schellenberger, G.; Reiprich, T. H.

2017-10-01

The X-ray bright, hot gas in the potential well of a galaxy cluster enables systematic X-ray studies of samples of galaxy clusters to constrain cosmological parameters. HIFLUGCS consists of the 64 X-ray brightest galaxy clusters in the Universe, building up a local sample. Here, we utilize this sample to determine, for the first time, individual hydrostatic mass estimates for all the clusters of the sample and, by making use of the completeness of the sample, we quantify constraints on the two interesting cosmological parameters, Ωm and σ8. We apply our total hydrostatic and gas mass estimates from the X-ray analysis to a Bayesian cosmological likelihood analysis and leave several parameters free to be constrained. We find Ωm = 0.30 ± 0.01 and σ8 = 0.79 ± 0.03 (statistical uncertainties, 68 per cent credibility level) using our default analysis strategy combining both a mass function analysis and the gas mass fraction results. The main sources of biases that we correct here are (1) the influence of galaxy groups (incompleteness in parent samples and differing behaviour of the Lx-M relation), (2) the hydrostatic mass bias, (3) the extrapolation of the total mass (comparing various methods), (4) the theoretical halo mass function and (5) other physical effects (non-negligible neutrino mass). We find that galaxy groups introduce a strong bias, since their number density seems to be over predicted by the halo mass function. On the other hand, incorporating baryonic effects does not result in a significant change in the constraints. The total (uncorrected) systematic uncertainties (∼20 per cent) clearly dominate the statistical uncertainties on cosmological parameters for our sample.

Establishing the accuracy of asteroseismic mass and radius estimates of giant stars - I. Three eclipsing systems at [Fe/H] ˜ -0.3 and the need for a large high-precision sample

NASA Astrophysics Data System (ADS)

Brogaard, K.; Hansen, C. J.; Miglio, A.; Slumstrup, D.; Frandsen, S.; Jessen-Hansen, J.; Lund, M. N.; Bossini, D.; Thygesen, A.; Davies, G. R.; Chaplin, W. J.; Arentoft, T.; Bruntt, H.; Grundahl, F.; Handberg, R.

2018-05-01

We aim to establish and improve the accuracy level of asteroseismic estimates of mass, radius, and age of giant stars. This can be achieved by measuring independent, accurate, and precise masses, radii, effective temperatures and metallicities of long period eclipsing binary stars with a red giant component that displays solar-like oscillations. We measured precise properties of the three eclipsing binary systems KIC 7037405, KIC 9540226, and KIC 9970396 and estimated their ages be 5.3 ± 0.5, 3.1 ± 0.6, and 4.8 ± 0.5 Gyr. The measurements of the giant stars were compared to corresponding measurements of mass, radius, and age using asteroseismic scaling relations and grid modelling. We found that asteroseismic scaling relations without corrections to Δν systematically overestimate the masses of the three red giants by 11.7 per cent, 13.7 per cent, and 18.9 per cent, respectively. However, by applying theoretical correction factors fΔν according to Rodrigues et al. (2017), we reached general agreement between dynamical and asteroseismic mass estimates, and no indications of systematic differences at the precision level of the asteroseismic measurements. The larger sample investigated by Gaulme et al. (2016) showed a much more complicated situation, where some stars show agreement between the dynamical and corrected asteroseismic measures while others suggest significant overestimates of the asteroseismic measures. We found no simple explanation for this, but indications of several potential problems, some theoretical, others observational. Therefore, an extension of the present precision study to a larger sample of eclipsing systems is crucial for establishing and improving the accuracy of asteroseismology of giant stars.

Constraining the mass–richness relationship of redMaPPer clusters with angular clustering

DOE PAGES

Baxter, Eric J.; Rozo, Eduardo; Jain, Bhuvnesh; ...

2016-08-04

The potential of using cluster clustering for calibrating the mass–richness relation of galaxy clusters has been recognized theoretically for over a decade. In this paper, we demonstrate the feasibility of this technique to achieve high-precision mass calibration using redMaPPer clusters in the Sloan Digital Sky Survey North Galactic Cap. By including cross-correlations between several richness bins in our analysis, we significantly improve the statistical precision of our mass constraints. The amplitude of the mass–richness relation is constrained to 7 per cent statistical precision by our analysis. However, the error budget is systematics dominated, reaching a 19 per cent total errormore » that is dominated by theoretical uncertainty in the bias–mass relation for dark matter haloes. We confirm the result from Miyatake et al. that the clustering amplitude of redMaPPer clusters depends on galaxy concentration as defined therein, and we provide additional evidence that this dependence cannot be sourced by mass dependences: some other effect must account for the observed variation in clustering amplitude with galaxy concentration. Assuming that the observed dependence of redMaPPer clustering on galaxy concentration is a form of assembly bias, we find that such effects introduce a systematic error on the amplitude of the mass–richness relation that is comparable to the error bar from statistical noise. Finally, the results presented here demonstrate the power of cluster clustering for mass calibration and cosmology provided the current theoretical systematics can be ameliorated.« less

Comparative study of the efficacy of topical steroid and antibiotic combination therapy versus oral antibiotic alone when treating acute rhinosinusitis.

PubMed

El-Hennawi, D M; Ahmed, M R; Farid, A M; Al Murtadah, A M

2015-05-01

Acute rhinosinusitis arises as a consequence of viral rhinitis, and bacterial infection can subsequently occur. Intranasal antibiotics as an adjunct to corticosteroids usually demonstrate the greatest symptom relief. We wanted to clinically evaluate the effects of a topical antibiotic and steroid combination administered intranasally, versus an oral antibiotic alone when treating acute rhinosinusitis. Forty patients with acute bacterial rhinosinusitis were divided into two groups. Group A received an antibiotic and steroid combination (ofloxacin 0.26 per cent and dexamethasone 0.053 per cent nasal drops) for 10 days, administered intranasally (5 drops in each nostril/8 hours). Group B, the control group, received an oral antibiotic alone (amoxicillin 90 mg/kg). Eight hours after commencing treatment, facial pain was more severe in group B and nasal obstruction was reduced in both groups. Ten days after commencing treatment, anterior nasal discharge was 0.15 per cent in group A and absent in group B. The application of a topical antibiotic and steroid combination into the nasal cavity is an effective way of treating uncomplicated, acute bacterial rhinosinusitis with the theoretical advantages of easy administration, high local drug concentration and minimal systemic adverse effects.

Evolution of density and velocity profiles of dark matter and dark energy in spherical voids

NASA Astrophysics Data System (ADS)

Novosyadlyj, Bohdan; Tsizh, Maksym; Kulinich, Yurij

2017-02-01

We analyse the evolution of cosmological perturbations which leads to the formation of large isolated voids in the Universe. We assume that initial perturbations are spherical and all components of the Universe (radiation, matter and dark energy) are continuous media with ideal fluid energy-momentum tensors, which interact only gravitationally. Equations of the evolution of perturbations for every component in the comoving to cosmological background reference frame are obtained from equations of energy and momentum conservation and Einstein's ones and are integrated numerically. Initial conditions are set at the early stage of evolution in the radiation-dominated epoch, when the scale of perturbation is much larger than the particle horizon. Results show how the profiles of density and velocity of matter and dark energy are formed and how they depend on parameters of dark energy and initial conditions. In particular, it is shown that final matter density and velocity amplitudes change within range ˜4-7 per cent when the value of equation-of-state parameter of dark energy w vary in the range from -0.8 to -1.2, and change within ˜1 per cent only when the value of effective sound speed of dark energy vary over all allowable range of its values.

Deep spectroscopy of nearby galaxy clusters - IV. The quench of the star formation in galaxies in the infall region of Abell 85

NASA Astrophysics Data System (ADS)

Aguerri, J. A. L.; Agulli, I.; Méndez-Abreu, J.

2018-06-01

Our aim is to understand the role of the environment in the quenching of star formation of galaxies located in the infall cluster region of Abell 85 (A85). This is achieved by studying the post-starburst galaxy population as tracer of recent quenching. By measuring the equivalent width (EW) of the [O II] and Hδ spectral lines, we classify the galaxies into three groups: passive (PAS), emission line (EL), and post-starburst (PSB) galaxies. The PSB galaxy population represents ˜ 4.5 per cent of the full sample. Dwarf galaxies (Mr > -18.0) account for ˜ 70 - 80 per cent of PSBs, which indicates that most of the galaxies undergoing recent quenching are low-mass objects. Independently of the environment, PSB galaxies are disc-like objects with g - r colour between the blue ELs and the red PAS ones. The PSB and EL galaxies in low-density environments show similar luminosities and local galaxy densities. The dynamics and local galaxy density of the PSB population in high-density environments are shared with PAS galaxies. However, PSB galaxies inside A85 are at shorter clustercentric radius than PAS and EL ones. The value of the EW(Hδ) is larger for those PSBs closer to the cluster centre. We propose two different physical mechanisms producing PSB galaxies depending on the environment. In low-density environments, gas-rich minor mergers or accretions could produce the PSB galaxies. For high-density environments like A85, PSBs would be produced by the removal of the gas reservoirs of EL galaxies by ram-pressure stripping when they pass near the cluster centre.

The SILCC (SImulating the LifeCycle of molecular Clouds) project - I. Chemical evolution of the supernova-driven ISM

NASA Astrophysics Data System (ADS)

Walch, S.; Girichidis, P.; Naab, T.; Gatto, A.; Glover, S. C. O.; Wünsch, R.; Klessen, R. S.; Clark, P. C.; Peters, T.; Derigs, D.; Baczynski, C.

2015-11-01

The SILCC (SImulating the Life-Cycle of molecular Clouds) project aims to self-consistently understand the small-scale structure of the interstellar medium (ISM) and its link to galaxy evolution. We simulate the evolution of the multiphase ISM in a (500 pc)2 × ±5 kpc region of a galactic disc, with a gas surface density of Σ _{_GAS} = 10 M_{⊙} pc^{-2}. The FLASH 4 simulations include an external potential, self-gravity, magnetic fields, heating and radiative cooling, time-dependent chemistry of H2 and CO considering (self-) shielding, and supernova (SN) feedback but omit shear due to galactic rotation. We explore SN explosions at different rates in high-density regions (peak), in random locations with a Gaussian distribution in the vertical direction (random), in a combination of both (mixed), or clustered in space and time (clus/clus2). Only models with self-gravity and a significant fraction of SNe that explode in low-density gas are in agreement with observations. Without self-gravity and in models with peak driving the formation of H2 is strongly suppressed. For decreasing SN rates, the H2 mass fraction increases significantly from <10 per cent for high SN rates, i.e. 0.5 dex above Kennicutt-Schmidt, to 70-85 per cent for low SN rates, i.e. 0.5 dex below KS. For an intermediate SN rate, clustered driving results in slightly more H2 than random driving due to the more coherent compression of the gas in larger bubbles. Magnetic fields have little impact on the final disc structure but affect the dense gas (n ≳ 10 cm-3) and delay H2 formation. Most of the volume is filled with hot gas (˜80 per cent within ±150 pc). For all but peak driving a vertically expanding warm component of atomic hydrogen indicates a fountain flow. We highlight that individual chemical species populate different ISM phases and cannot be accurately modelled with temperature-/density-based phase cut-offs.

The size distribution of inhabited planets

NASA Astrophysics Data System (ADS)

Simpson, Fergus

2016-02-01

Earth-like planets are expected to provide the greatest opportunity for the detection of life beyond the Solar system. However, our planet cannot be considered a fair sample, especially if intelligent life exists elsewhere. Just as a person's country of origin is a biased sample among countries, so too their planet of origin may be a biased sample among planets. The magnitude of this effect can be substantial: over 98 per cent of the world's population live in a country larger than the median. In the context of a simple model where the mean population density is invariant to planet size, we infer that a given inhabited planet (such as our nearest neighbour) has a radius r < 1.2r⊕ (95 per cent confidence bound). We show that this result is likely to hold not only for planets hosting advanced life, but also for those which harbour primitive life forms. Further, inferences may be drawn for any variable which influences population size. For example, since population density is widely observed to decline with increasing body mass, we conclude that most intelligent species are expected to exceed 300 kg.

Bending stresses in spherically hollow ball bearing and fatigue experiments

NASA Technical Reports Server (NTRS)

Nypan, L. J.; Coe, H. H.; Parker, R. J.

1975-01-01

Spherically hollow balls of 21.7, 50.0 and 56.5 per cent mass reduction have been operated in ball bearings and in a 5-ball fatigue tester with differing outcomes. Available theoretical and experimental treatments of stresses in spherically hollow balls are reviewed and compared. Bending stresses are estimated for these spherically hollow balls to better understand the differences in ball bearing and fatigue test experience.

Navigation by light polarization in clear and turbid waters

PubMed Central

Lerner, Amit; Sabbah, Shai; Erlick, Carynelisa; Shashar, Nadav

2011-01-01

Certain terrestrial animals use sky polarization for navigation. Certain aquatic species have also been shown to orient according to a polarization stimulus, but the correlation between underwater polarization and Sun position and hence the ability to use underwater polarization as a compass for navigation is still under debate. To examine this issue, we use theoretical equations for per cent polarization and electric vector (e-vector) orientation that account for the position of the Sun, refraction at the air–water interface and Rayleigh single scattering. The polarization patterns predicted by these theoretical equations are compared with measurements conducted in clear and semi-turbid coastal sea waters at 2 m and 5 m depth over sea floors of 6 m and 28 m depth. We find that the per cent polarization is correlated with the Sun's elevation only in clear waters. We furthermore find that the maximum value of the e-vector orientation angle equals the angle of refraction only in clear waters, in the horizontal viewing direction, over the deeper sea floor. We conclude that navigation by use of underwater polarization is possible under restricted conditions, i.e. in clear waters, primarily near the horizontal viewing direction, and in locations where the sea floor has limited effects on the light's polarization. PMID:21282170

Winds of change: reionization by starburst galaxies

NASA Astrophysics Data System (ADS)

Sharma, Mahavir; Theuns, Tom; Frenk, Carlos; Bower, Richard G.; Crain, Robert A.; Schaller, Matthieu; Schaye, Joop

2017-06-01

We investigate the properties of the galaxies that reionized the Universe and the history of cosmic reionization using the 'Evolution and Assembly of Galaxies and their Environments' (eagle) cosmological hydrodynamical simulations. We obtain the evolution of the escape fraction of ionizing photons in galaxies assuming that galactic winds create channels through which 20 per cent of photons escape when the local surface density of star formation is greater than 0.1 M⊙ yr-1 kpc-2. Such threshold behaviour for the generation of winds is observed, and the rare local objects that have such high star formation surface densities exhibit high escape fractions of ˜10 per cent. In our model, the luminosity-weighted mean escape fraction increases with redshift as \\bar{f}_esc=0.045 ((1+z)/4)^{1.1} at z > 3, and the galaxy number weighted mean as = 2.2 × 10-3 ((1 + z)/4)4, and becomes constant ≈0.2 at redshift z > 10. The escape fraction evolves as an increasingly large fraction of stars forms above the critical surface density of star formation at earlier times. This evolution of the escape fraction, combined with that of the star formation rate density from eagle, reproduces the inferred evolution of the filling factor of ionized regions during the reionization epoch (6 < z < 8), the evolution of the post-reionization (0 ≤ z < 6) hydrogen photoionization rate and the optical depth due to Thomson scattering of the cosmic microwave background photons measured by the Planck satellite.

Dense cloud cores revealed by CO in the low metallicity dwarf galaxy WLM.

PubMed

Rubio, Monica; Elmegreen, Bruce G; Hunter, Deidre A; Brinks, Elias; Cortés, Juan R; Cigan, Phil

2015-09-10

Understanding stellar birth requires observations of the clouds in which they form. These clouds are dense and self-gravitating, and in all existing observations they are molecular, with H2 the dominant species and carbon monoxide (CO) the best available tracer. When the abundances of carbon and oxygen are low compared with that of hydrogen, and the opacity from dust is also low, as in primeval galaxies and local dwarf irregular galaxies, CO forms slowly and is easily destroyed, so it is difficult for it to accumulate inside dense clouds. Here we report interferometric observations of CO clouds in the local group dwarf irregular galaxy Wolf-Lundmark-Melotte (WLM), which has a metallicity that is 13 per cent of the solar value and 50 per cent lower than the previous CO detection threshold. The clouds are tiny compared to the surrounding atomic and H2 envelopes, but they have typical densities and column densities for CO clouds in the Milky Way. The normal CO density explains why star clusters forming in dwarf irregulars have similar densities to star clusters in giant spiral galaxies. The low cloud masses suggest that these clusters will also be low mass, unless some galaxy-scale compression occurs, such as an impact from a cosmic cloud or other galaxy. If the massive metal-poor globular clusters in the halo of the Milky Way formed in dwarf galaxies, as is commonly believed, then they were probably triggered by such an impact.

Star-disc interaction in galactic nuclei: formation of a central stellar disc

NASA Astrophysics Data System (ADS)

Panamarev, Taras; Shukirgaliyev, Bekdaulet; Meiron, Yohai; Berczik, Peter; Just, Andreas; Spurzem, Rainer; Omarov, Chingis; Vilkoviskij, Emmanuil

2018-05-01

We perform high-resolution direct N-body simulations to study the effect of an accretion disc on stellar dynamics in an active galactic nucleus (AGN). We show that the interaction of the nuclear stellar cluster (NSC) with the gaseous accretion disc (AD) leads to formation of a stellar disc in the central part of the NSC. The accretion of stars from the stellar disc on to the super-massive black hole is balanced by the capture of stars from the NSC into the stellar disc, yielding a stationary density profile. We derive the migration time through the AD to be 3 per cent of the half-mass relaxation time of the NSC. The mass and size of the stellar disc are 0.7 per cent of the mass and 5 per cent of the influence radius of the super-massive black hole. An AD lifetime shorter than the migration time would result in a less massive nuclear stellar disc. The detection of such a stellar disc could point to past activity of the hosting galactic nucleus.

Comparing the capitalisation benefits of light-rail transit and overlay zoning for single-family houses and condos by neighbourhood type in metropolitan Phoenix, Arizona.

PubMed

Atkinson-Palombo, Carol

2010-01-01

Light rail transit (LRT) is increasingly accompanied by overlay zoning which specifies the density and type of future development to encourage landscapes conducive to transit use. Neighbourhood type (based on land use mix) is used to partition data and investigate how pre-existing land use, treatment with a park-and-ride (PAR) versus walk-and-ride (WAR) station and overlay zoning interrelate. Hedonic models estimate capitalisation effects of LRT-related accessibility and overlay zoning on single-family houses and condos in different neighbourhoods for the system in metropolitan Phoenix, Arizona. Impacts differ by housing and neighbourhood type. Amenity-dominated mixed-use neighbourhoods-predominantly WAR communities-experience premiums of 6 per cent for single-family houses and over 20 per cent for condos, the latter boosted an additional 37 per cent by overlay zoning. Residential neighbourhoods-predominantly PAR communities-experience no capitalisation benefits for single-family houses and a discount for condos. The results suggest that land use mix is an important variable to select comparable neighbourhoods.

Near-infrared counterparts to the Galactic Bulge Survey X-ray source population

NASA Astrophysics Data System (ADS)

Greiss, S.; Steeghs, D.; Jonker, P. G.; Torres, M. A. P.; Maccarone, T. J.; Hynes, R. I.; Britt, C. T.; Nelemans, G.; Gänsicke, B. T.

2014-03-01

We report on the near-infrared matches, drawn from three surveys, to the 1640 unique X-ray sources detected by Chandra in the Galactic Bulge Survey (GBS). This survey targets faint X-ray sources in the bulge, with a particular focus on accreting compact objects. We present all viable counterpart candidates and associate a false alarm probability (FAP) to each near-infrared match in order to identify the most likely counterparts. The FAP takes into account a statistical study involving a chance alignment test, as well as considering the positional accuracy of the individual X-ray sources. We find that although the star density in the bulge is very high, ˜90 per cent of our sources have an FAP <10 per cent, indicating that for most X-ray sources, viable near-infrared counterparts candidates can be identified. In addition to the FAP, we provide positional and photometric information for candidate counterparts to ˜95 per cent of the GBS X-ray sources. This information in combination with optical photometry, spectroscopy and variability constraints will be crucial to characterize and classify secure counterparts.

The origins of post-starburst galaxies at z < 0.05

NASA Astrophysics Data System (ADS)

Pawlik, M. M.; Taj Aldeen, L.; Wild, V.; Mendez-Abreu, J.; Lahén, N.; Johansson, P. H.; Jimenez, N.; Lucas, W.; Zheng, Y.; Walcher, C. J.; Rowlands, K.

2018-06-01

Post-starburst galaxies can be identified via the presence of prominent Hydrogen Balmer absorption lines in their spectra. We present a comprehensive study of the origin of strong Balmer lines in a volume-limited sample of 189 galaxies with 0.01 < z < 0.05, log ({M}_{\\star }/{M}_{⊙})>9.5 and projected axial ratio b/a > 0.32. We explore their structural properties, environments, emission lines, and star formation histories, and compare them to control samples of star-forming and quiescent galaxies, and simulated galaxy mergers. Excluding contaminants, in which the strong Balmer lines are most likely caused by dust-star geometry, we find evidence for three different pathways through the post-starburst phase, with most events occurring in intermediate-density environments: (1) a significant disruptive event, such as a gas-rich major merger, causing a starburst and growth of a spheroidal component, followed by quenching of the star formation (70 per cent of post-starburst galaxies at 9.5< log ({M}_{\\star}/{M}_{⊙})<10.5 and 60 per cent at log ({M}_{\\star}/{M}_{⊙})>10.5); (2) at 9.5< log ({M}_{\\star}/{M}_{⊙})<10.5, stochastic star formation in blue-sequence galaxies, causing a weak burst and subsequent return to the blue sequence (30 per cent); (3) at log ({M}_{\\star}/{M}_{⊙})>10.5, cyclic evolution of quiescent galaxies which gradually move towards the high-mass end of the red sequence through weak starbursts, possibly as a result of a merger with a smaller gas-rich companion (40 per cent). Our analysis suggests that active galactic nuclei (AGNs) are 'on' for 50 per cent of the duration of the post-starburst phase, meaning that traditional samples of post-starburst galaxies with strict emission-line cuts will be at least 50 per cent incomplete due to the exclusion of narrow-line AGNs.

The 25 parsec local white dwarf population

NASA Astrophysics Data System (ADS)

Holberg, J. B.; Oswalt, T. D.; Sion, E. M.; McCook, G. P.

2016-11-01

We have extended our detailed survey of the local white dwarf population from 20 to 25 pc, effectively doubling the sample volume, which now includes 232 stars. In the process, new stars within 20 pc have been added, a more uniform set of distance estimates as well as improved spectral and binary classifications are available. The present 25 pc sample is estimated to be about 68 per cent complete (the corresponding 20 pc sample is now 86 per cent complete). The space density of white dwarfs is unchanged at 4.8 ± 0.5 × 10-3 pc-3. This new study includes a white dwarf mass distribution and luminosity function based on the 232 stars in the 25 pc sample. We find a significant excess of single stars over systems containing one or more companions (74 per cent versus 26 per cent). This suggests mechanisms that result in the loss of companions during binary system evolution. In addition, this updated sample exhibits a pronounced deficiency of nearby `Sirius-like' systems. 11 such systems were found within the 20 pc volume versus only one additional system found in the volume between 20 and 25 pc. An estimate of white dwarf birth rates during the last ˜8 Gyr is derived from individual remnant cooling ages. A discussion of likely ways new members of the local sample may be found is provided.

The Star Formation Reference Survey - II. Activity demographics and host-galaxy properties for infrared-selected galaxies

NASA Astrophysics Data System (ADS)

Maragkoudakis, A.; Zezas, A.; Ashby, M. L. N.; Willner, S. P.

2018-04-01

We present activity demographics and host-galaxy properties of infrared-selected galaxies in the local Universe, using the representative Star Formation Reference Survey (SFRS). Our classification scheme is based on a combination of optical emission-line diagrams (BPT) and infrared (IR)-colour diagnostics. Using the weights assigned to the SFRS galaxies based on its parent sample, a far-IR-selected sample comprises 71 per cent H II galaxies, 13 per cent Seyferts, 3 per cent transition objects (TOs), and 13 per cent low-ionization nuclear emission-line regions (LINERs). For the SFRS H II galaxies, we derive nuclear star formation rates and gas-phase metallicities. We measure host-galaxy metallicities for all galaxies with available long-slit spectroscopy and abundance gradients for a subset of 12 face-on galaxies. The majority of H II galaxies show a narrow range of metallicities, close to solar, and flat metallicity profiles. Based on their host-galaxy and nuclear properties, the dominant ionizing source in the far-infrared selected TOs is star-forming activity. LINERs are found mostly in massive hosts (median of 1010.5 M⊙), median L(60 μm) = 109 L⊙, median dust temperatures of F60/F100 = 0.36, and median LH α surface density of 1040.2 erg s-1kpc-2, indicating older stellar populations as their main ionizing source rather than active galactic nucleus activity.

Cylinders out of a top hat: counts-in-cells for projected densities

NASA Astrophysics Data System (ADS)

Uhlemann, Cora; Pichon, Christophe; Codis, Sandrine; L'Huillier, Benjamin; Kim, Juhan; Bernardeau, Francis; Park, Changbom; Prunet, Simon

2018-06-01

Large deviation statistics is implemented to predict the statistics of cosmic densities in cylinders applicable to photometric surveys. It yields few per cent accurate analytical predictions for the one-point probability distribution function (PDF) of densities in concentric or compensated cylinders; and also captures the density dependence of their angular clustering (cylinder bias). All predictions are found to be in excellent agreement with the cosmological simulation Horizon Run 4 in the quasi-linear regime where standard perturbation theory normally breaks down. These results are combined with a simple local bias model that relates dark matter and tracer densities in cylinders and validated on simulated halo catalogues. This formalism can be used to probe cosmology with existing and upcoming photometric surveys like DES, Euclid or WFIRST containing billions of galaxies.

The effect of gas physics on the halo mass function

NASA Astrophysics Data System (ADS)

Stanek, R.; Rudd, D.; Evrard, A. E.

2009-03-01

Cosmological tests based on cluster counts require accurate calibration of the space density of massive haloes, but most calibrations to date have ignored complex gas physics associated with halo baryons. We explore the sensitivity of the halo mass function to baryon physics using two pairs of gas-dynamic simulations that are likely to bracket the true behaviour. Each pair consists of a baseline model involving only gravity and shock heating, and a refined physics model aimed at reproducing the observed scaling of the hot, intracluster gas phase. One pair consists of billion-particle resimulations of the original 500h-1Mpc Millennium Simulation of Springel et al., run with the smoothed particle hydrodynamics (SPH) code GADGET-2 and using a refined physics treatment approximated by pre-heating (PH) at high redshift. The other pair are high-resolution simulations from the adaptive-mesh refinement code ART, for which the refined treatment includes cooling, star formation and supernova feedback (CSF). We find that, although the mass functions of the gravity-only (GO) treatments are consistent with the recent calibration of Tinker et al. (2008), both pairs of simulations with refined baryon physics show significant deviations. Relative to the GO case, the masses of ~1014h-1Msolar haloes in the PH and CSF treatments are shifted by the averages of -15 +/- 1 and +16 +/- 2 per cent, respectively. These mass shifts cause ~30 per cent deviations in number density relative to the Tinker function, significantly larger than the 5 per cent statistical uncertainty of that calibration.

Calculation of thermal conductivity, thermal diffusivity and specific heat capacity of sedimentary rocks using petrophysical well logs

NASA Astrophysics Data System (ADS)

Fuchs, Sven; Balling, Niels; Förster, Andrea

2015-12-01

In this study, equations are developed that predict for synthetic sedimentary rocks (clastics, carbonates and evapourates) thermal properties comprising thermal conductivity, specific heat capacity and thermal diffusivity. The rock groups are composed of mineral assemblages with variable contents of 15 major rock-forming minerals and porosities of 0-30 per cent. Petrophysical properties and their well-logging-tool-characteristic readings were assigned to these rock-forming minerals and to pore-filling fluids. Relationships are explored between each thermal property and other petrophysical properties (density, sonic interval transit time, hydrogen index, volume fraction of shale and photoelectric absorption index) using multivariate statistics. The application of these relations allows computing continuous borehole profiles for each rock thermal property. The uncertainties in the prediction of each property vary depending on the selected well-log combination. Best prediction is in the range of 2-8 per cent for the specific heat capacity, of 5-10 per cent for the thermal conductivity, and of 8-15 for the thermal diffusivity, respectively. Well-log derived thermal conductivity is validated by laboratory data measured on cores from deep boreholes of the Danish Basin, the North German Basin, and the Molasse Basin. Additional validation of thermal conductivity was performed by comparing predicted and measured temperature logs. The maximum deviation between these logs is <3 °C. The thermal-conductivity calculation allowed an evaluation of the depth range in which the palaeoclimatic effect on the subsurface temperature field can be observed in the North German Basin. This effect reduces the surface heat-flow density by 25 mW m-2.

Wide- and contact-binary formation in substructured young stellar clusters

NASA Astrophysics Data System (ADS)

Dorval, J.; Boily, C. M.; Moraux, E.; Roos, O.

2017-02-01

We explore with collisional gravitational N-body models the evolution of binary stars in initially fragmented and globally subvirial clusters of stars. Binaries are inserted in the (initially) clumpy configurations so as to match the observed distributions of the field-binary-stars' semimajor axes a and binary fraction versus primary mass. The dissolution rate of wide binaries is very high at the start of the simulations, and is much reduced once the clumps are eroded by the global infall. The transition between the two regimes is sharper as the number of stars N is increased, from N = 1.5 k up to 80 k. The fraction of dissolved binary stars increases only mildly with N, from ≈15 per cent to ≈25 per cent for the same range in N. We repeated the calculation for two initial system mean number densities of 6 per pc3 (low) and 400 per pc3 (high). We found that the longer free-fall time of the low-density runs allows for prolonged binary-binary interactions inside clumps and the formation of very tight (a ≈ 0.01 au) binaries by exchange collisions. This is an indication that the statistics of such compact binaries bear a direct link to their environment at birth. We also explore the formation of wide (a ≳ 5 × 104 au) binaries and find a low (≈0.01 per cent) fraction mildly bound to the central star cluster. The high-precision astrometric mission Gaia could identify them as outflowing shells or streams.

The low-frequency radio eclipses of the black widow pulsar J1810+1744

NASA Astrophysics Data System (ADS)

Polzin, E. J.; Breton, R. P.; Clarke, A. O.; Kondratiev, V. I.; Stappers, B. W.; Hessels, J. W. T.; Bassa, C. G.; Broderick, J. W.; Grießmeier, J.-M.; Sobey, C.; ter Veen, S.; van Leeuwen, J.; Weltevrede, P.

2018-05-01

We have observed and analysed the eclipses of the black widow pulsar J1810+1744 at low radio frequencies. Using LOw-Frequency ARray (LOFAR) and Westerbork Synthesis Radio Telescope observations between 2011 and 2015, we have measured variations in flux density, dispersion measure, and scattering around eclipses. High-time resolution, simultaneous beamformed, and interferometric imaging LOFAR observations show concurrent disappearance of pulsations and total flux from the source during the eclipses, with a 3σ upper limit of 36 mJy ( < 10 per cent of the pulsar's averaged out-of-eclipse flux density). The dispersion measure variations are highly asymmetric, suggesting a tail of material swept back due to orbital motion. The egress deviations are variable on time-scales shorter than the 3.6 h orbital period and are indicative of a clumpy medium. Additional pulse broadening detected during egress is typically < 20 per cent of the pulsar's spin period, showing no evidence of scattering the pulses beyond detectability in the beamformed data. The eclipses, lasting ˜ 13 per cent of the orbit at 149 MHz, are shown to be frequency-dependent with total duration scaling as ∝ ν-0.41 ± 0.03. The results are discussed in the context of the physical parameters of the system, and an examination of eclipse mechanisms reveals cyclotron-synchrotron absorption as the most likely primary cause, although non-linear scattering mechanisms cannot be quantitatively ruled out. The inferred mass-loss rate is a similar order of magnitude to the mean rate required to fully evaporate the companion in a Hubble time.

Hierarchical clustering in chameleon f(R) gravity

NASA Astrophysics Data System (ADS)

Hellwing, Wojciech A.; Li, Baojiu; Frenk, Carlos S.; Cole, Shaun

2013-11-01

We use a suite of high-resolution state-of-the-art N-body dark matter simulations of chameleon f(R) gravity to study the higher order volume-averaged correlation functions overline{ξ _n} together with the hierarchical nth-order correlation amplitudes S_n=overline{ξ }_n/overline{ξ }_2^{n-1} and density distribution functions (PDF). We show that under the non-linear modifications of gravity the hierarchical scaling of the reduced cumulants is preserved. This is however characterized by significant changes in the values of both overline{ξ _n} and Sn and their scale dependence with respect to General Relativity gravity (GR). In addition, we measure a significant increase of the non-linear σ8 parameter reaching 14, 5 and 0.5 per cent in excess of the GR value for the three flavours of our f(R) models. We further note that the values of the reduced cumulants up to order n = 9 are significantly increased in f(R) gravity for all our models at small scales R ≲ 30 h-1 Mpc. In contrast, the values of the hierarchical amplitudes, Sn, are smaller in f(R) indicating that the modified gravity density distribution functions are deviating from the GR case. Furthermore, we find that the redshift evolution of relative deviations of the f(R) hierarchical correlation amplitudes is fastest at high and moderate redshifts 1 ≤ z ≤ 4. The growth of these deviations significantly slows down in the low-redshift universe. We also compute the PDFs and show that for scales below ˜20 h-1 Mpc, they are significantly shifted in f(R) gravity towards the low densities. Finally, we discuss the implications of our theoretical predictions for measurements of the hierarchical clustering in galaxy redshift surveys, including the important problems of the galaxy biasing and redshift space distortions.

Constraining the galaxy mass content in the core of A383 using velocity dispersion measurements for individual cluster members

NASA Astrophysics Data System (ADS)

Monna, A.; Seitz, S.; Zitrin, A.; Geller, M. J.; Grillo, C.; Mercurio, A.; Greisel, N.; Halkola, A.; Suyu, S. H.; Postman, M.; Rosati, P.; Balestra, I.; Biviano, A.; Coe, D.; Fabricant, D. G.; Hwang, H. S.; Koekemoer, A.

2015-02-01

We use velocity dispersion measurements of 21 individual cluster members in the core of Abell 383, obtained with Multiple Mirror Telescope Hectospec, to separate the galaxy and the smooth dark halo (DH) lensing contributions. While lensing usually constrains the overall, projected mass density, the innovative use of velocity dispersion measurements as a proxy for masses of individual cluster members breaks inherent degeneracies and allows us to (a) refine the constraints on single galaxy masses and on the galaxy mass-to-light scaling relation and, as a result, (b) refine the constraints on the DM-only map, a high-end goal of lens modelling. The knowledge of cluster member velocity dispersions improves the fit by 17 per cent in terms of the image reproduction χ2, or 20 per cent in terms of the rms. The constraints on the mass parameters improve by ˜10 per cent for the DH, while for the galaxy component, they are refined correspondingly by ˜50 per cent, including the galaxy halo truncation radius. For an L* galaxy with M^{*}B=-20.96, for example, we obtain best-fitting truncation radius r_tr^{*}=20.5^{+9.6}_{-6.7} kpc and velocity dispersion σ* = 324 ± 17 km s-1. Moreover, by performing the surface brightness reconstruction of the southern giant arc, we improve the constraints on rtr of two nearby cluster members, which have measured velocity dispersions, by more than ˜30 per cent. We estimate the stripped mass for these two galaxies, getting results that are consistent with numerical simulations. In the future, we plan to apply this analysis to other galaxy clusters for which velocity dispersions of member galaxies are available.

The JCMT Plane Survey: first complete data release - emission maps and compact source catalogue

NASA Astrophysics Data System (ADS)

Eden, D. J.; Moore, T. J. T.; Plume, R.; Urquhart, J. S.; Thompson, M. A.; Parsons, H.; Dempsey, J. T.; Rigby, A. J.; Morgan, L. K.; Thomas, H. S.; Berry, D.; Buckle, J.; Brunt, C. M.; Butner, H. M.; Carretero, D.; Chrysostomou, A.; Currie, M. J.; deVilliers, H. M.; Fich, M.; Gibb, A. G.; Hoare, M. G.; Jenness, T.; Manser, G.; Mottram, J. C.; Natario, C.; Olguin, F.; Peretto, N.; Pestalozzi, M.; Polychroni, D.; Redman, R. O.; Salji, C.; Summers, L. J.; Tahani, K.; Traficante, A.; diFrancesco, J.; Evans, A.; Fuller, G. A.; Johnstone, D.; Joncas, G.; Longmore, S. N.; Martin, P. G.; Richer, J. S.; Weferling, B.; White, G. J.; Zhu, M.

2017-08-01

We present the first data release of the James Clerk Maxwell Telescope Plane Survey (JPS), the JPS Public Release 1. JPS is an 850-μm continuum survey of six fields in the northern inner Galactic plane in a longitude range of ℓ = 7°-63°, made with the Submillimetre Common-User Bolometer Array 2. This first data release consists of emission maps of the six JPS regions with an average pixel-to-pixel noise of 7.19 mJy beam-1, when smoothed over the beam, and a compact source catalogue containing 7813 sources. The 95 per cent completeness limits of the catalogue are estimated at 0.04 Jy beam-1 and 0.3 Jy for the peak and integrated flux densities, respectively. The emission contained in the compact source catalogue is 42 ± 5 per cent of the total and, apart from the large-scale (greater than 8 arcmin) emission, there is excellent correspondence with features in the 500-μm Herschel maps. We find that, with two-dimensional matching, 98 ± 2 per cent of sources within the fields centred at ℓ = 20°, 30°, 40° and 50° are associated with molecular clouds, with 91 ± 3 per cent of the ℓ = 30° and 40° sources associated with dense molecular clumps. Matching the JPS catalogue to Herschel 70-μm sources, we find that 38 ± 1 per cent of sources show evidence of ongoing star formation. The JPS Public Release 1 images and catalogue will be a valuable resource for studies of star formation in the Galaxy and the role of environment and spiral arms in the star formation process.

The KMOS Redshift One Spectroscopic Survey (KROSS): dynamical properties, gas and dark matter fractions of typical z ˜ 1 star-forming galaxies

NASA Astrophysics Data System (ADS)

Stott, John P.; Swinbank, A. M.; Johnson, Helen L.; Tiley, Alfie; Magdis, Georgios; Bower, Richard; Bunker, Andrew J.; Bureau, Martin; Harrison, Chris M.; Jarvis, Matt J.; Sharples, Ray; Smail, Ian; Sobral, David; Best, Philip; Cirasuolo, Michele

2016-04-01

The KMOS Redshift One Spectroscopic Survey (KROSS) is an ESO-guaranteed time survey of 795 typical star-forming galaxies in the redshift range z = 0.8-1.0 with the KMOS instrument on the Very Large Telescope. In this paper, we present resolved kinematics and star formation rates for 584 z ˜ 1 galaxies. This constitutes the largest near-infrared Integral Field Unit survey of galaxies at z ˜ 1 to date. We demonstrate the success of our selection criteria with 90 per cent of our targets found to be H α emitters, of which 81 per cent are spatially resolved. The fraction of the resolved KROSS sample with dynamics dominated by ordered rotation is found to be 83 ± 5 per cent. However, when compared with local samples these are turbulent discs with high gas to baryonic mass fractions, ˜35 per cent, and the majority are consistent with being marginally unstable (Toomre Q ˜ 1). There is no strong correlation between galaxy averaged velocity dispersion and the total star formation rate, suggesting that feedback from star formation is not the origin of the elevated turbulence. We postulate that it is the ubiquity of high (likely molecular) gas fractions and the associated gravitational instabilities that drive the elevated star formation rates in these typical z ˜ 1 galaxies, leading to the 10-fold enhanced star formation rate density. Finally, by comparing the gas masses obtained from inverting the star formation law with the dynamical and stellar masses, we infer an average dark matter to total mass fraction within 2.2re (9.5 kpc) of 65 ± 12 per cent, in agreement with the results from hydrodynamic simulations of galaxy formation.

When feedback fails: the scaling and saturation of star formation efficiency

NASA Astrophysics Data System (ADS)

Grudić, Michael Y.; Hopkins, Philip F.; Faucher-Giguère, Claude-André; Quataert, Eliot; Murray, Norman; Kereš, Dušan

2018-04-01

We present a suite of 3D multiphysics MHD simulations following star formation in isolated turbulent molecular gas discs ranging from 5 to 500 parsecs in radius. These simulations are designed to survey the range of surface densities between those typical of Milky Way giant molecular clouds (GMCs) ({˜ } 10^2 {M_{\\odot } pc^{-2}}) and extreme ultraluminous infrared galaxy environments ({˜ } 10^4 {M_{\\odot } pc^{-2}}) so as to map out the scaling of the cloud-scale star formation efficiency (SFE) between these two regimes. The simulations include prescriptions for supernova, stellar wind, and radiative feedback, which we find to be essential in determining both the instantaneous per-freefall (ɛff) and integrated (ɛint) star formation efficiencies. In all simulations, the gas discs form stars until a critical stellar surface density has been reached and the remaining gas is blown out by stellar feedback. We find that surface density is a good predictor of ɛint, as suggested by analytic force balance arguments from previous works. SFE eventually saturates to ˜1 at high surface density. We also find a proportional relationship between ɛff and ɛint, implying that star formation is feedback-moderated even over very short time-scales in isolated clouds. These results have implications for star formation in galactic discs, the nature and fate of nuclear starbursts, and the formation of bound star clusters. The scaling of ɛff with surface density is not consistent with the notion that ɛff is always ˜ 1 per cent on the scale of GMCs, but our predictions recover the ˜ 1 per cent value for GMC parameters similar to those found in spiral galaxies, including our own.

The ugrizYJHK luminosity distributions and densities from the combined MGC, SDSS and UKIDSS LAS data sets

NASA Astrophysics Data System (ADS)

Hill, David T.; Driver, Simon P.; Cameron, Ewan; Cross, Nicholas; Liske, Jochen; Robotham, Aaron

2010-05-01

We combine data from the Millennium Galaxy Catalogue, Sloan Digital Sky Survey and UKIRT Infrared Deep Sky Survey Large Area Survey to produce ugrizYJHK luminosity functions and densities from within a common, low-redshift volume (z < 0.1, ~ 71000h-31 Mpc3 for L* systems) with 100 per cent spectroscopic completeness. In the optical the fitted Schechter functions are comparable in shape to those previously reported values but with higher normalizations (typically 0, 30, 20, 15, 5 per cent higher φ* values in u, g, r, i, z, respectively, over those reported by the SDSS team). We attribute these to differences in the redshift ranges probed, incompleteness and adopted normalization methods. In the near-IR (NIR) we find significantly different Schechter function parameters (mainly in the M* values) to those previously reported and attribute this to the improvement in the quality of the imaging data over previous studies. This is the first homogeneous measurement of the extragalactic luminosity density which fully samples both the optical and NIR regimes. Unlike previous compilations that have noted a discontinuity between the optical and NIR regimes our homogeneous data set shows a smooth cosmic spectral energy distribution (CSED). After correcting for dust attenuation we compare our CSED to the expected values based on recent constraints on the cosmic star formation history and the initial mass function.

Encircling the dark: constraining dark energy via cosmic density in spheres

NASA Astrophysics Data System (ADS)

Codis, S.; Pichon, C.; Bernardeau, F.; Uhlemann, C.; Prunet, S.

2016-08-01

The recently published analytic probability density function for the mildly non-linear cosmic density field within spherical cells is used to build a simple but accurate maximum likelihood estimate for the redshift evolution of the variance of the density, which, as expected, is shown to have smaller relative error than the sample variance. This estimator provides a competitive probe for the equation of state of dark energy, reaching a few per cent accuracy on wp and wa for a Euclid-like survey. The corresponding likelihood function can take into account the configuration of the cells via their relative separations. A code to compute one-cell-density probability density functions for arbitrary initial power spectrum, top-hat smoothing and various spherical-collapse dynamics is made available online, so as to provide straightforward means of testing the effect of alternative dark energy models and initial power spectra on the low-redshift matter distribution.

Prey and predator emigration responses in the acarine system Tetranychus urticae-Phytoseiulus persimilis.

PubMed

Bernstein, C

1984-01-01

Some of the processes that influence the emigration of prey and predatory mites from bean plants were investigated experimentally. The emigration of the prey depends on the damage they cause to the plants and on predator density. The predator's emigration rate is a decreasing function of prey density, and does not change (or it slightly decreases) when prey and predator numbers are increased maintaining the same prey/predator ratio. The probability of emigration of the predators is independent of their own density when prey are absent and density dependent when prey density is kep constant. Forty three per cent of the variability in the predator's instantaneous rate of emigration in the different experiments is accounted for by a two parameter negative exponential function of capture rate (number of prey eaten per predator and per unit of time).

Evaluating the influence of septic systems and watershed characteristics on stream faecal pollution in suburban watersheds in Georgia, USA.

PubMed

Sowah, R; Zhang, H; Radcliffe, D; Bauske, E; Habteselassie, M Y

2014-11-01

To determine the impact of septic systems on water quality and in so doing identify watershed level characteristics that influence septic system impact. Water samples were collected from streams in 24 well-characterized watersheds during baseflow to analyse for the levels of faecal indicators Escherichia coli and enterococci. The watersheds represent a gradient of land-use conditions from low to high density of septic systems, as well as developed to undeveloped uses. Our findings indicate statistically significant interaction between septic density and season for enterococci count (P = 0·005) and stream yield (P = 0·04). Seasonal variations in bacterial count and stream yield were also observed, with significant differences between spring-winter and summer-winter. Results from multiple linear regression models suggest that watershed characteristics (septic system density, median distance of septic systems to stream, per cent developed area and forest cover) and water temperature could explain approximately half (R(2) = 0·50) of the variability in bacterial count and yield in spring and summer. There is a significant positive relationship between septic system density and faecal pollution levels. However, this relationship is season dependent and is influenced by watershed level characteristics such as median distance of septic systems from streams, per cent developed area and forest cover. This study confirms the significant impact of septic systems on faecal pollution during baseflow and provides the tools that will enable effective pollution monitoring at the watershed scale. © 2014 The Society for Applied Microbiology.

Observational constraints on neutron star crust-core coupling during glitches

NASA Astrophysics Data System (ADS)

Newton, W. G.; Berger, S.; Haskell, B.

2015-12-01

We demonstrate that observations of glitches in the Vela pulsar can be used to investigate the strength of the crust-core coupling in a neutron star and provide a powerful probe of the internal structure of neutron stars. We assume that glitch recovery is dominated by the torque exerted by the mutual friction-mediated recoupling of superfluid components of the core that were decoupled from the crust during the glitch. Then we use the observations of the recoveries from two recent glitches in the Vela pulsar to infer the fraction of the core that is coupled to the crust during the glitch. We then analyse whether crustal neutrons alone are sufficient to drive glitches in the Vela pulsar, taking into account crustal entrainment. We use two sets of neutron star equations of state (EOSs) which span crust and core consistently and cover a conservative range of the slope of the symmetry energy at saturation density 30 < L < 120 MeV. The two sets differ in the stiffness of the high density EOS. We find that for medium to stiff EOSs, observations imply >70 per cent of the moment of inertia of the core is coupled to the crust during the glitch, though for softer EOSs L ≈ 30 MeV as little as 5 per cent could be coupled. We find that only by extending the region where superfluid vortices are strongly pinned into the core by densities at least 0.016 fm-3 above the crust-core transition density does any EOS reproduce the observed glitch activity.

High-resolution SMA imaging of bright submillimetre sources from the SCUBA-2 Cosmology Legacy Survey

NASA Astrophysics Data System (ADS)

Hill, Ryley; Chapman, Scott C.; Scott, Douglas; Petitpas, Glen; Smail, Ian; Chapin, Edward L.; Gurwell, Mark A.; Perry, Ryan; Blain, Andrew W.; Bremer, Malcolm N.; Chen, Chian-Chou; Dunlop, James S.; Farrah, Duncan; Fazio, Giovanni G.; Geach, James E.; Howson, Paul; Ivison, R. J.; Lacaille, Kevin; Michałowski, Michał J.; Simpson, James M.; Swinbank, A. M.; van der Werf, Paul P.; Wilner, David J.

2018-06-01

We have used the Submillimeter Array (SMA) at 860 μm to observe the brightest sources in the Submillimeter Common User Bolometer Array-2 (SCUBA-2) Cosmology Legacy Survey (S2CLS). The goal of this survey is to exploit the large field of the S2CLS along with the resolution and sensitivity of the SMA to construct a large sample of these rare sources and to study their statistical properties. We have targeted 70 of the brightest single-dish SCUBA-2 850 μm sources down to S850 ≈ 8 mJy, achieving an average synthesized beam of 2.4 arcsec and an average rms of σ860 = 1.5 mJy beam-1 in our primary beam-corrected maps. We searched our SMA maps for 4σ peaks, corresponding to S860 ≳ 6 mJy sources, and detected 62, galaxies, including three pairs. We include in our study 35 archival observations, bringing our sample size to 105 bright single-dish submillimetre sources with interferometric follow-up. We compute the cumulative and differential number counts, finding them to overlap with previous single-dish survey number counts within the uncertainties, although our cumulative number count is systematically lower than the parent S2CLS cumulative number count by 14 ± 6 per cent between 11 and 15 mJy. We estimate the probability that a ≳10 mJy single-dish submillimetre source resolves into two or more galaxies with similar flux densities to be less than 15 per cent. Assuming the remaining 85 per cent of the targets are ultraluminous starburst galaxies between z = 2 and 3, we find a likely volume density of ≳400 M⊙ yr-1 sources to be {˜ } 3^{+0.7}_{-0.6} {× } 10^{-7} Mpc-3. We show that the descendants of these galaxies could be ≳4 × 1011 M⊙ local quiescent galaxies, and that about 10 per cent of their total stellar mass would have formed during these short bursts of star formation.

Density probability distribution functions of diffuse gas in the Milky Way

NASA Astrophysics Data System (ADS)

Berkhuijsen, E. M.; Fletcher, A.

2008-10-01

In a search for the signature of turbulence in the diffuse interstellar medium (ISM) in gas density distributions, we determined the probability distribution functions (PDFs) of the average volume densities of the diffuse gas. The densities were derived from dispersion measures and HI column densities towards pulsars and stars at known distances. The PDFs of the average densities of the diffuse ionized gas (DIG) and the diffuse atomic gas are close to lognormal, especially when lines of sight at |b| < 5° and |b| >= 5° are considered separately. The PDF of at high |b| is twice as wide as that at low |b|. The width of the PDF of the DIG is about 30 per cent smaller than that of the warm HI at the same latitudes. The results reported here provide strong support for the existence of a lognormal density PDF in the diffuse ISM, consistent with a turbulent origin of density structure in the diffuse gas.

PREPARATION OF SPHERICAL URANIUM DIOXIDE PARTICLES

DOEpatents

Levey, R.P. Jr.; Smith, A.E.

1963-04-30

This patent relates to the preparation of high-density, spherical UO/sub 2/ particles 80 to 150 microns in diameter. Sinterable UO/sub 2/ powder is wetted with 3 to 5 weight per cent water and tumbled for at least 48 hours. The resulting spherical particles are then sintered. The sintered particles are useful in dispersion-type fuel elements for nuclear reactors. (AEC)

Surface study and sensing activity of nanotubular indium trioxide to NH3, H2S, NO2 and CO environmental pollutants

NASA Astrophysics Data System (ADS)

Zamani, Mehdi

2016-02-01

Molecular and electronic structures of nanotubular indium trioxide were studied using B3LYP and CAM-B3LYP density functional methods. Three nanotube models including nanotubes with closed ends (CENT), one opened end (OOENT) and two opened ends (TOENT) were considered. The highest occupied molecular orbital (HOMO) of CENT is distributed over the entire nanotube; while it is distributed on the end cap of OOENT. In both CENT and OOENT, the distribution of the lowest unoccupied molecular orbital (LUMO) is on the end caps. HOMO and LUMO of TOENT are distributed on the center of nanotube. The sensing activity of OOENT to environmental pollutants was evaluated regarding the interaction of nanotube with NH3, H2S, NO2 and CO molecules. Adsorptions over different positions of OOENT are exothermic and the NH3 adsorption is thermodynamically more favorable. The selectivity of OOENT toward gaseous pollutants is investigated as NH3 > H2S > CO > NO2. Interaction of NO2 and CO over the closed end (end cap) of nanotube is preferred; while adsorption of NH3 and H2S on the opened end is more favorable.

The anterior component of occlusal force revisited: direct measurement and theoretical considerations.

PubMed

Al Qassar, Sarmad S Salih; Mavragani, Maria; Psarras, Vasilis; Halazonetis, Demetrios J

2016-04-01

The anterior component of occlusal force (ACF), considered to result from the mesial inclination of teeth relative to the occlusal plane, has been estimated by indirectly measuring contact point tightness (CPT) through interproximal insertion of metal strips. ACF has been observed concurrently with a posterior component, whose theoretical origin is difficult to explain. Evaluate ACF by measuring CPT directly, and integrate current data to propose a theoretical basis for ACF. The sample comprised 14 females (age: 22.3±2.8) and 16 males (age: 20.8±2.5). Our device consisted of two force sensors: one for measuring maximum bite force (MBF) (overall thickness: 4mm), and one for measuring CPT directly (0.2mm thick), inserted between the lower first molar and second premolar. ACF was computed as the difference in CPT between the biting (at 75 per cent of MBF) and non-biting conditions. Averages of MBF, CPT, and ACF were 666.67 [standard deviation (SD): 36.06], 6.74 (SD: 1.17), and 20.59 (SD: 4.60) N, respectively. ACF, CPT, and MBF were higher in males by approximately 28, 18 and 7 per cent, respectively. A positive correlation was observed between ACF and MBF (R (2): 0.64). CPT was also significantly correlated to MBF (R (2): 0.40). Biomechanical analysis indicates that previously offered explanations do not unriddle the concurrent increase of CPT at anterior and posterior contact points. ACF was related to bite force by a logarithmic model. We speculate that CPT increases during biting through a combination of mesial tipping of teeth and mandibular bending. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

COS-Weak: probing the CGM using analogues of weak Mg II absorbers at z < 0.3

NASA Astrophysics Data System (ADS)

Muzahid, S.; Fonseca, G.; Roberts, A.; Rosenwasser, B.; Richter, P.; Narayanan, A.; Churchill, C.; Charlton, J.

2018-06-01

We present a sample of 34 weak metal line absorbers at z < 0.3 selected by the simultaneous >3σ detections of the Si IIλ1260 and C IIλ1334 absorption lines, with Wr(Si II)<0.2 Å and Wr(C II)<0.3 Å, in archival HST/COS spectra. Our sample increases the number of known low-z `weak absorbers' by a factor of >5. The column densities of H I and low-ionization metal lines obtained from Voigt profile fitting are used to build simple photoionization models. The inferred densities and line-of-sight thicknesses of the absorbers are in the ranges of -3.3 < log nH/cm-3 < -2.4 and ˜1 pc-50 kpc (median ≈500 pc), respectively. Most importantly, 85 per cent (50 per cent) of these absorbers show a metallicity of [Si/H] > -1.0 (0.0). The fraction of systems showing near-/supersolar metallicity in our sample is significantly higher than in the H I-selected sample of Wotta et al., and the galaxy-selected sample of Prochaska et al., of absorbers probing the circum-galactic medium at similar redshift. A search for galaxies has revealed a significant galaxy-overdensity around these weak absorbers compared to random positions with a median impact parameter of 166 kpc from the nearest galaxy. Moreover, we find the presence of multiple galaxies in ≈80 per cent of the cases, suggesting group environments. The observed dN/dz of 0.8 ± 0.2 indicates that such metal-enriched, compact, dense structures are ubiquitous in the haloes of low-z group galaxies. We suggest that these are transient structures that are related to galactic outflows and/or stripping of metal-rich gas from galaxies.

The MASSIVE survey - VIII. Stellar velocity dispersion profiles and environmental dependence of early-type galaxies

NASA Astrophysics Data System (ADS)

Veale, Melanie; Ma, Chung-Pei; Greene, Jenny E.; Thomas, Jens; Blakeslee, John P.; Walsh, Jonelle L.; Ito, Jennifer

2018-02-01

We measure the radial profiles of the stellar velocity dispersions, σ(R), for 90 early-type galaxies (ETGs) in the MASSIVE survey, a volume-limited integral-field spectroscopic (IFS) galaxy survey targeting all northern-sky ETGs with absolute K-band magnitude MK < -25.3 mag, or stellar mass M* ≳ 4 × 1011M⊙, within 108 Mpc. Our wide-field 107 arcsec × 107 arcsec IFS data cover radii as large as 40 kpc, for which we quantify separately the inner (2 kpc) and outer (20 kpc) logarithmic slopes γinner and γouter of σ(R). While γinner is mostly negative, of the 56 galaxies with sufficient radial coverage to determine γouter we find 36 per cent to have rising outer dispersion profiles, 30 per cent to be flat within the uncertainties and 34 per cent to be falling. The fraction of galaxies with rising outer profiles increases with M* and in denser galaxy environment, with 10 of the 11 most massive galaxies in our sample having flat or rising dispersion profiles. The strongest environmental correlations are with local density and halo mass, but a weaker correlation with large-scale density also exists. The average γouter is similar for brightest group galaxies, satellites and isolated galaxies in our sample. We find a clear positive correlation between the gradients of the outer dispersion profile and the gradients of the velocity kurtosis h4. Altogether, our kinematic results suggest that the increasing fraction of rising dispersion profiles in the most massive ETGs are caused (at least in part) by variations in the total mass profiles rather than in the velocity anisotropy alone.

Swift observations of V404 Cyg during the 2015 outburst: X-ray outflows from super-Eddington accretion

NASA Astrophysics Data System (ADS)

Motta, S. E.; Kajava, J. J. E.; Sánchez-Fernández, C.; Beardmore, A. P.; Sanna, A.; Page, K. L.; Fender, R.; Altamirano, D.; Charles, P.; Giustini, M.; Knigge, C.; Kuulkers, E.; Oates, S.; Osborne, J. P.

2017-10-01

The black hole (BH) binary V404 Cyg entered the outburst phase in 2015 June after 26 yr of X-ray quiescence, and with its behaviour broke the outburst evolution pattern typical of most BH binaries. We observed the entire outburst with the Swift satellite and performed time-resolved spectroscopy of its most active phase, obtaining over a thousand spectra with exposures from tens to hundreds of seconds. All the spectra can be fitted with an absorbed power-law model, which most of the time required the presence of a partial covering. A blueshifted iron-Kα line appears in 10 per cent of the spectra together with the signature of high column densities, and about 20 per cent of the spectra seem to show signatures of reflection. None of the spectra showed the unambiguous presence of soft disc-blackbody emission, while the observed bolometric flux exceeded the Eddington value in 3 per cent of the spectra. Our results can be explained assuming that the inner part of the accretion flow is inflated into a slim disc that both hides the innermost (and brightest) regions of the flow, and produces a cold, clumpy, high-density outflow that introduces the high absorption and fast spectral variability observed. We argue that the BH in V404 Cyg might have been accreting erratically or even continuously at Eddington/super-Eddington rates - thus sustaining a surrounding slim disc - while being partly or completely obscured by the inflated disc and its outflow. Hence, the largest flares produced by the source might not be accretion-driven events, but instead the effects of the unveiling of the extremely bright source hidden within the system.

A parametric description of the 3D structure of the Galactic bar/bulge using the VVV survey

NASA Astrophysics Data System (ADS)

Simion, I. T.; Belokurov, V.; Irwin, M.; Koposov, S. E.; Gonzalez-Fernandez, C.; Robin, A. C.; Shen, J.; Li, Z.-Y.

2017-11-01

We study the structure of the inner Milky Way using the latest data release of the VISTA Variables in the Via Lactea (VVV) survey. The VVV is a deep near-infrared, multi-colour photometric survey with a coverage of 300 square degrees towards the bulge/bar. We use red clump (RC) stars to produce a high-resolution dust map of the VVV's field of view. From de-reddened colour-magnitude diagrams, we select red giant branch stars to investigate their 3D density distribution within the central 4 kpc. We demonstrate that our best-fitting parametric model of the bulge density provides a good description of the VVV data, with a median percentage residual of 5 per cent over the fitted region. The strongest of the otherwise low-level residuals are overdensities associated with a low-latitude structure as well as the so-called X-shape previously identified using the split RC. These additional components contribute only ˜5 per cent and ˜7 per cent respectively to the bulge mass budget. The best-fitting bulge is `boxy' with an axial ratio of [1:0.44:0.31] and is rotated with respect to the Sun-Galactic Centre line by at least 20°. We provide an estimate of the total, full sky, mass of the bulge of M_bulge^{Chabrier} = 2.36 × 10^{10} M_{⊙} for a Chabrier initial mass function. We show that there exists a strong degeneracy between the viewing angle and the dispersion of the RC absolute magnitude distribution. The value of the latter is strongly dependent on the assumptions made about the intrinsic luminosity function of the bulge.

Kinetic Parameter Measurements in the MINERVE Reactor

NASA Astrophysics Data System (ADS)

Perret, Grégory; Geslot, Benoit; Gruel, Adrien; Blaise, Patrick; Di-Salvo, Jacques; De Izarra, Grégoire; Jammes, Christian; Hursin, Mathieu; Pautz, Andréas

2017-01-01

In the framework of an international collaboration, teams of the PSI and CEA research institutes measure the critical decay constant (α0 = β/A), delayed neutron fraction (β) and generation time (A) of the Minerve reactor using the Feynman-α, Power Spectral Density and Rossi-α neutron noise measurement techniques. These measurements contribute to the experimental database of kinetic parameters used to improve nuclear data files and validate modern methods in Monte Carlo codes. Minerve is a zero-power pool reactor composed of a central experimental test lattice surrounded by a large aluminum buffer and four high-enriched driver regions. Measurements are performed in three slightly subcritical configurations (-2 cents to -30 cents) using two high-efficiency 235U fission chambers in the driver regions. Measurement of α0 and β obtained by the two institutes and with the different techniques are consistent for the configurations envisaged. Slight increases of the β values are observed with the subcriticality level. Best estimate values are obtained with the Cross-Power Spectral Density technique at -2 cents, and are worth: β = 716.9±9.0 pcm, α0 = 79.0±0.6 s-1 and A = 90.7±1.4 μs. The kinetic parameters are predicted with MCNP5-v1.6 and TRIPOLI4.9 and the JEFF-3.1/3.1.1 and ENDF/B-VII.1 nuclear data libraries. The predictions for β and α0 overestimate the experimental results by 3-5% and 10-12%, respectively; that for A underestimate the experimental result by 6-7%. The discrepancies are suspected to come from the driven system nature of Minerve and the location of the detectors in the driver regions, which prevent accounting for the full reactor.

The development of a nutritious low cost weaning food for Kenya infants.

PubMed

Ward, D; Ainsworth, P

1998-01-01

The aim of this research was to develop an inexpensive weaning food of adequate dietary energy, protein and fat, for an infant of four to six months, that can be manufactured in Kenya, using readily available resources and technology. Product formulation was developed by using low cost, readily available and culturally acceptable food products. A cooked porridge was prepared using the traditional oven top method. Subsequently, the porridge was drum dried, blended with ground pumpkin seeds, heat sealed and stored at ambient temperature (22 degrees Centigrade) for eight weeks. Chemical analysis was then carried out to determine the total percentage energy, protein, fat and carbohydrate content of the dried mix. All were in accordance with the theoretical values. This analysis indicated that in order to meet the recommended daily allowances for fat and energy, the addition of oil was necessary, this value was calculated theoretically. In vitro protein digestibility was 82.5 per cent, confirming a high quality protein food. HPLC analysis detected no free floating water soluble amino acids, indicating food stability. A low peroxide value was found, confirming a rancid free food. Viscometer analysis of the reconstituted mix confirmed a nutrient and energy dense food at an acceptable consistency for infant feeding. The addition of a small amount of oil, to the reconstituted mix lowered the viscosity, allowing for the addition of an increase in the quality of dried mix, increasing both nutrient and energy density. The organoleptic qualities of the food were evaluated by a semi-trained panel. The overall appearance was highly rated, with flavour slightly less favourable.

Endectocide activity of a pour-on formulation containing 1.5 per cent ivermectin +0.5 per cent abamectin in cattle.

PubMed

Silva, Heloisa Cristina; Prette, Nancy; Lopes, Welber Daniel Zanetti; Sakamoto, Cláudio Alessandro M; Buzzulini, Carolina; Dos Santos, Thais Rabelo; Cruz, Breno Cayeiro; Teixeira, Weslen F Pires; Felippelli, Gustavo; Carvalho, Rafael Silveira; Maciel, Willian Giquelin; Soares, Vando Edésio; da Costa, Alvimar José

2015-01-01

The present work aimed to evaluate, through ten different studies, the therapeutic efficacy of a new pour-on formulation, containing 1.5 per cent ivermectin +0.5 per cent abamectin, against parasites of cattle. Results obtained on trials against Rhipicephalus (Boophilus) microplus showed that the pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained superior efficacy indexes against this ectoparasite, when compared with formulations containing 0.5 per cent ivermectin, 1 per cent ivermectin and the combination of 1 per cent abamectin +20 per cent levamisole. The results of efficacy of the ivermectin+abamectin and the 0.5 per cent ivermectin against Haematobia irritans were similar. Against Cochliomyia hominivorax larvae, all pour-on formulations tested (1.5 per cent ivermectin +0.5 per cent abamectin, 0.5 per cent ivermectin and 0.5 per cent abamectin), as well as 1 per cent doramectin administered subcutaneously, were considered ineffective. Cattle medicated with 1.5 per cent ivermectin +0.5 per cent abamectin, pour-on, remained free from parasitism by Dermatobia hominis larvae during 42 days (96 per cent efficacy), while values superior to 90 per cent were obtained by 0.5 per cent ivermectin (92 per cent) and 0.5 per cent abamectin (93 per cent) until the 42nd and 35th days post treatment, respectively. Against Haemonchus placei and Oesophagostomum radiatum, the pour-on of ivermectin+abamectin showed better efficacy than the 0.5 per cent ivermectin and 0.5 per cent abamectin. As to Cooperia punctata, there was no difference regarding efficacy results obtained by the avermectins combination and abamectin. The pour-on combination of 1.5 per cent ivermectin +0.5 per cent abamectin obtained high efficacy against R. (B.) microplus, D. hominis and some species of cattle gastrointestinal helminths when compared with formulations of 0.5 per cent ivermectin and 0.5 per cent abamectin administered through the same route.

Racism, ethnic density and psychological well-being through adolescence: evidence from the Determinants of Adolescent Social Well-Being and Health longitudinal study.

PubMed

Astell-Burt, Thomas; Maynard, Maria J; Lenguerrand, Erik; Harding, Seeromanie

2012-01-01

To investigate the effect of racism, own-group ethnic density, diversity and deprivation on adolescent trajectories in psychological well-being. Multilevel models were used in longitudinal analysis of psychological well-being (total difficulties score (TDS) from Goodman's Strengths and Difficulties Questionnaire, higher scores correspond to greater difficulties) for 4782 adolescents aged 11-16 years in 51 London (U.K.) schools. Individual level variables included ethnicity, racism, gender, age, migrant generation, socio-economic circumstances, family type and indicators of family interactions (shared activities, perceived parenting). Contextual variables were per cent eligible for free school-meals, neighbourhood deprivation, per cent own-group ethnic density, and ethnic diversity. Ethnic minorities were more likely to report racism than whites. Ethnic minority boys (except Indian boys) and Indian girls reported better psychological well-being throughout adolescence compared to their white peers. Notably, lowest mean TDS scores were observed for Nigerian/Ghanaian boys, among whom the reporting of racism increased with age. Adjusted for individual characteristics, psychological well-being improved with age across all ethnic groups. Racism was associated with poorer psychological well-being trajectories for all ethnic groups (p<0.001), reducing with age. For example, mean difference in TDS (95% confidence interval) between boys who experienced racism and those who did not at age 12 years=1.88 (+1.75 to +2.01); at 16 years = +1.19 (+1.07 to +1.31). Less racism was generally reported in schools and neighbourhoods with high than low own-group density. Own ethnic density and diversity were not consistently associated with TDS for any ethnic group. Living in more deprived neighbourhoods was associated with poorer psychological well-being for whites and black Caribbeans (p<0.05). Racism, but not ethnic density and deprivation in schools or neighbourhoods, was an important influence on psychological well-being. However, exposure to racism did not explain the advantage in psychological well-being of ethnic minority groups over whites.

The SAMI Galaxy Survey: spatially resolving the environmental quenching of star formation in GAMA galaxies

NASA Astrophysics Data System (ADS)

Schaefer, A. L.; Croom, S. M.; Allen, J. T.; Brough, S.; Medling, A. M.; Ho, I.-T.; Scott, N.; Richards, S. N.; Pracy, M. B.; Gunawardhana, M. L. P.; Norberg, P.; Alpaslan, M.; Bauer, A. E.; Bekki, K.; Bland-Hawthorn, J.; Bloom, J. V.; Bryant, J. J.; Couch, W. J.; Driver, S. P.; Fogarty, L. M. R.; Foster, C.; Goldstein, G.; Green, A. W.; Hopkins, A. M.; Konstantopoulos, I. S.; Lawrence, J. S.; López-Sánchez, A. R.; Lorente, N. P. F.; Owers, M. S.; Sharp, R.; Sweet, S. M.; Taylor, E. N.; van de Sande, J.; Walcher, C. J.; Wong, O. I.

2017-01-01

We use data from the Sydney-AAO Multi-Object Integral Field Spectrograph Galaxy Survey and the Galaxy And Mass Assembly (GAMA) survey to investigate the spatially resolved signatures of the environmental quenching of star formation in galaxies. Using dust-corrected measurements of the distribution of Hα emission, we measure the radial profiles of star formation in a sample of 201 star-forming galaxies covering three orders of magnitude in stellar mass (M*; 108.1-1010.95 M⊙) and in fifth nearest neighbour local environment density (Σ5; 10-1.3-102.1 Mpc-2). We show that star formation rate gradients in galaxies are steeper in dense (log10(Σ5/Mpc2) > 0.5) environments by 0.58 ± 0.29 dex re^{-1} in galaxies with stellar masses in the range 10^{10} < M_{*}/M_{⊙} < 10^{11} and that this steepening is accompanied by a reduction in the integrated star formation rate. However, for any given stellar mass or environment density, the star formation morphology of galaxies shows large scatter. We also measure the degree to which the star formation is centrally concentrated using the unitless scale-radius ratio (r50,Hα/r50,cont), which compares the extent of ongoing star formation to previous star formation. With this metric, we find that the fraction of galaxies with centrally concentrated star formation increases with environment density, from ˜5 ± 4 per cent in low-density environments (log10(Σ5/Mpc2) < 0.0) to 30 ± 15 per cent in the highest density environments (log10(Σ5/Mpc2) > 1.0). These lines of evidence strongly suggest that with increasing local environment density, the star formation in galaxies is suppressed, and that this starts in their outskirts such that quenching occurs in an outside-in fashion in dense environments and is not instantaneous.

A Detection of the Baryon Acoustic Oscillation Features in the SDSS BOSS DR12 Galaxy Bispectrum

NASA Astrophysics Data System (ADS)

Pearson, David W.; Samushia, Lado

2018-05-01

We present the first high significance detection (4.1σ) of the Baryon Acoustic Oscillations (BAO) feature in the galaxy bispectrum of the twelfth data release (DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS sample (0.43 ≤ z ≤ 0.7). We measured the scale dilation parameter, α, using the power spectrum, bispectrum, and both simultaneously for DR12, plus 2048 MultiDark-PATCHY mocks in the North and South Galactic Caps (NGC and SGC, respectively), and the volume weighted averages of those two samples (N+SGC). The fitting to the mocks validated our analysis pipeline, yielding values consistent with the mock cosmology. By fitting to the power spectrum and bispectrum separately, we tested the robustness of our results, finding consistent values from the NGC, SGC and N+SGC in all cases. We found DV = 2032 ± 24(stat.) ± 15(sys.) Mpc, DV = 2038 ± 55(stat.) ± 15(sys.) Mpc, and DV = 2031 ± 22(stat.) ± 10(sys.) Mpc from the N+SGC power spectrum, bispectrum and simultaneous fitting, respectively. Our bispectrum measurement precision was mainly limited by the size of the covariance matrix. Based on the fits to the mocks, we showed that if a less noisy estimator of the covariance were available, from either a theoretical computation or a larger suite of mocks, the constraints from the bispectrum and simultaneous fits would improve to 1.1 per cent (1.3 per cent with systematics) and 0.7 per cent (0.9 per cent with systematics), respectively, with the latter being slightly more precise than the power spectrum only constraints from the reconstructed field.

Cobalt carbide nanoprisms for direct production of lower olefins from syngas

NASA Astrophysics Data System (ADS)

Zhong, Liangshu; Yu, Fei; An, Yunlei; Zhao, Yonghui; Sun, Yuhan; Li, Zhengjia; Lin, Tiejun; Lin, Yanjun; Qi, Xingzhen; Dai, Yuanyuan; Gu, Lin; Hu, Jinsong; Jin, Shifeng; Shen, Qun; Wang, Hui

2016-10-01

Lower olefins—generally referring to ethylene, propylene and butylene—are basic carbon-based building blocks that are widely used in the chemical industry, and are traditionally produced through thermal or catalytic cracking of a range of hydrocarbon feedstocks, such as naphtha, gas oil, condensates and light alkanes. With the rapid depletion of the limited petroleum reserves that serve as the source of these hydrocarbons, there is an urgent need for processes that can produce lower olefins from alternative feedstocks. The ‘Fischer-Tropsch to olefins’ (FTO) process has long offered a way of producing lower olefins directly from syngas—a mixture of hydrogen and carbon monoxide that is readily derived from coal, biomass and natural gas. But the hydrocarbons obtained with the FTO process typically follow the so-called Anderson-Schulz-Flory distribution, which is characterized by a maximum C2-C4 hydrocarbon fraction of about 56.7 per cent and an undesired methane fraction of about 29.2 per cent (refs 1, 10, 11, 12). Here we show that, under mild reaction conditions, cobalt carbide quadrangular nanoprisms catalyse the FTO conversion of syngas with high selectivity for the production of lower olefins (constituting around 60.8 per cent of the carbon products), while generating little methane (about 5.0 per cent), with the ratio of desired unsaturated hydrocarbons to less valuable saturated hydrocarbons amongst the C2-C4 products being as high as 30. Detailed catalyst characterization during the initial reaction stage and theoretical calculations indicate that preferentially exposed {101} and {020} facets play a pivotal role during syngas conversion, in that they favour olefin production and inhibit methane formation, and thereby render cobalt carbide nanoprisms a promising new catalyst system for directly converting syngas into lower olefins.

Research and development on membrane processes for removal of acid gases during coal gasification. Final report, 20 June 1975-19 October 1976

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

Petersen, R.J.; Cadotte, J.E.; Conway, E.J.

1976-01-01

The object of this program was to develop novel and unique membranes for separating acid gases from coal gasification streams. Many candidate membranes, including cationic, hydrophilic, and silicone, were tested. Optimum separation properties were possessed by membranes formulated from crosslinked methyl cellulose coated on polysulfone support films. The observed separation properties were explained theoretically by the solubility of the various gases in the water contained within the membranes rather than by activated transport. Each of the acid gas clean-up processes considered required additional sulfur clean-up, a guard chamber, and a Claus plant for recovering sulfur. These additional costs were calculatedmore » and added to the base costs for acid gas removal from the raw SNG. When the additional costs were added to the costs of the Rectisol, Benfield, Sulfinol, and fluidized dolomite processes the total costs ranged from 43 to 49 cents/Mscf. For the membrane process the additional sulfur removal costs were about 3.3 cents/Mscf to be added to the base costs for acid gas removal. The best membrane composition found during this program, one which exhibited a CO/sub 2//H/sub 2/ selectivity of 13 at a CO/sub 2/ flux of 6 ft/sup 3//ft/sup 2/-hr-100 psi, would entail a process cost of about 53 cents/Mscf with these additions. This is about 7 cents/Mscf more than for the average of the other processes. No better membrane performance is predicted on the basis of the experiments performed. Without a shift in several cost factors, membranes cannot be competitive. The possibility that reduced energy availability could lead to such shifts should not be discounted but is not foreseen in the near future.« less

Ultrafast outflows in radio-loud active galactic nuclei

NASA Astrophysics Data System (ADS)

Tombesi, F.; Tazaki, F.; Mushotzky, R. F.; Ueda, Y.; Cappi, M.; Gofford, J.; Reeves, J. N.; Guainazzi, M.

2014-09-01

Recent X-ray observations show absorbing winds with velocities up to mildly relativistic values of the order of ˜0.1c in a limited sample of six broad-line radio galaxies. They are observed as blueshifted Fe XXV-XXVI K-shell absorption lines, similarly to the ultrafast outflows (UFOs) reported in Seyferts and quasars. In this work we extend the search for such Fe K absorption lines to a larger sample of 26 radio-loud active galactic nuclei (AGN) observed with XMM-Newton and Suzaku. The sample is drawn from the Swift Burst Alert Telescope 58-month catalogue and blazars are excluded. X-ray bright Fanaroff-Riley Class II radio galaxies constitute the majority of the sources. Combining the results of this analysis with those in the literature we find that UFOs are detected in >27 per cent of the sources. However, correcting for the number of spectra with insufficient signal-to-noise ratio, we can estimate that the incidence of UFOs is this sample of radio-loud AGN is likely in the range f ≃ (50 ± 20) per cent. A photoionization modelling of the absorption lines with XSTAR allows us to estimate the distribution of their main parameters. The observed outflow velocities are broadly distributed between vout ≲ 1000 km s-1 and vout ≃ 0.4c, with mean and median values of vout ≃ 0.133c and vout ≃ 0.117c, respectively. The material is highly ionized, with an average ionization parameter of logξ ≃ 4.5 erg s-1 cm, and the column densities are larger than NH > 1022 cm-2. Overall, these characteristics are consistent with the presence of complex accretion disc winds in a significant fraction of radio-loud AGN and demonstrate that the presence of relativistic jets does not preclude the existence of winds, in accordance with several theoretical models.

The QDOT all-sky IRAS galaxy redshift survey

NASA Astrophysics Data System (ADS)

Lawrence, A.; Rowan-Robinson, M.; Ellis, R. S.; Frenk, C. S.; Efstathiou, G.; Kaiser, N.; Saunders, W.; Parry, I. R.; Xiaoyang, Xia; Crawford, J.

1999-10-01

We describe the construction of the QDOT survey, which is publicly available from an anonymous FTP account. The catalogue consists of infrared properties and redshifts of an all-sky sample of 2387 IRAS galaxies brighter than the IRAS PSC 60-μm completeness limit (S_60>0.6Jy), sparsely sampled at a rate of one-in-six. At |b|>10 deg, after removing a small number of Galactic sources, the redshift completeness is better than 98per cent (2086/2127). New redshifts for 1401 IRAS sources were obtained to complete the catalogue; the measurement and reduction of these are described, and the new redshifts tabulated here. We also tabulate all sources at |b|>10 deg with no redshift so far, and sources with conflicting alternative redshifts either from our own work, or from published velocities. A list of 95 ultraluminous galaxies (i.e. with L_60μm>10^12 L_solar) is also provided. Of these, ~20per cent are AGN of some kind; the broad-line objects typically show strong Feii emission. Since the publication of the first QDOT papers, there have been several hundred velocity changes: some velocities are new, some QDOT velocities have been replaced by more accurate values, and some errors have been corrected. We also present a new analysis of the accuracy and linearity of IRAS 60-μm fluxes. We find that the flux uncertainties are well described by a combination of 0.05-Jy fixed size uncertainty and 8per cent fractional uncertainty. This is not enough to cause the large Malmquist-type errors in the rate of evolution postulated by Fisher et al. We do, however, find marginal evidence for non-linearity in the PSC 60-μm flux scale, in the sense that faint sources may have fluxes overestimated by about 5per cent compared with bright sources. We update some of the previous scientific analyses to assess the changes. The main new results are as follows. (1) The luminosity function is very well determined overall but is uncertain by a factor of several at the very highest luminosities (L_60μm>5x10^12L_solar), as this is where the remaining unidentified objects are almost certainly concentrated. (2) The best-fitting rate of evolution is somewhat lower than our previous estimate; expressed as pure density evolution with density varying as (1+z)^p, we find p=5.6+/-2.3. Making a rough correction for the possible (but very uncertain) non-linearity of fluxes, we find p=4.5+/-2.3. (3) The dipole amplitude decreases a little, and the implied value of the density parameter, assuming that IRAS galaxies trace the mass, is Ω=0.9(+0.45, -0.25). (4) Finally, the estimate of density variance on large scales changes negligibly, still indicating a significant discrepancy from the predictions of simple cold dark matter cosmogonies.

A per-cent-level determination of the nucleon axial coupling from quantum chromodynamics.

PubMed

Chang, C C; Nicholson, A N; Rinaldi, E; Berkowitz, E; Garron, N; Brantley, D A; Monge-Camacho, H; Monahan, C J; Bouchard, C; Clark, M A; Joó, B; Kurth, T; Orginos, K; Vranas, P; Walker-Loud, A

2018-06-01

The axial coupling of the nucleon, g A , is the strength of its coupling to the weak axial current of the standard model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic current. This axial coupling dictates the rate at which neutrons decay to protons, the strength of the attractive long-range force between nucleons and other features of nuclear physics. Precision tests of the standard model in nuclear environments require a quantitative understanding of nuclear physics that is rooted in quantum chromodynamics, a pillar of the standard model. The importance of g A makes it a benchmark quantity to determine theoretically-a difficult task because quantum chromodynamics is non-perturbative, precluding known analytical methods. Lattice quantum chromodynamics provides a rigorous, non-perturbative definition of quantum chromodynamics that can be implemented numerically. It has been estimated that a precision of two per cent would be possible by 2020 if two challenges are overcome 1,2 : contamination of g A from excited states must be controlled in the calculations and statistical precision must be improved markedly 2-10 . Here we use an unconventional method 11 inspired by the Feynman-Hellmann theorem that overcomes these challenges. We calculate a g A value of 1.271 ± 0.013, which has a precision of about one per cent.

Synthetic Stellar Photometry - II. Testing the bolometric flux scale and tables of bolometric corrections for the Hipparcos/Tycho, Pan-STARRS1, SkyMapper, and JWST systems

NASA Astrophysics Data System (ADS)

Casagrande, L.; VandenBerg, Don A.

2018-04-01

We use MARCS model atmosphere fluxes to compute synthetic colours, bolometric corrections and reddening coefficients for the Hipparcos/Tycho, Pan-STARRS1, SkyMapper, and JWST systems. Tables and interpolation subroutines are provided to transform isochrones from the theoretical to various observational planes, to derive bolometric corrections, synthetic colours and colour-temperature relations at nearly any given point of the HR diagram for 2600 K ≤ Teff ≤ 8000 K, and different values of reddening in 85 photometric filters. We use absolute spectrophotometry from the CALSPEC library to show that bolometric fluxes can be recovered to ˜2 per cent from bolometric corrections in a single band, when input stellar parameters are well known for FG dwarfs at various metallicities. This sole source of uncertainty impacts interferometric Teff to ≃0.5 per cent (or 30 K at the solar temperature). Uncertainties are halved when combining bolometric corrections in more bands, and limited by the fundamental uncertainty of the current absolute flux scale at 1 per cent. Stars in the RAVE DR5 catalogue are used to validate the quality of our MARCS synthetic photometry in selected filters across the optical and infrared range. This investigation shows that extant MARCS synthetic fluxes are able to reproduce the main features observed in stellar populations across the Galactic disc.

Simulating the interaction of jets with the intracluster medium

NASA Astrophysics Data System (ADS)

Weinberger, Rainer; Ehlert, Kristian; Pfrommer, Christoph; Pakmor, Rüdiger; Springel, Volker

2017-10-01

Jets from supermassive black holes in the centres of galaxy clusters are a potential candidate for moderating gas cooling and subsequent star formation through depositing energy in the intracluster gas. In this work, we simulate the jet-intracluster medium interaction using the moving-mesh magnetohydrodynamics code arepo. Our model injects supersonic, low-density, collimated and magnetized outflows in cluster centres, which are then stopped by the surrounding gas, thermalize and inflate low-density cavities filled with cosmic rays. We perform high-resolution, non-radiative simulations of the lobe creation, expansion and disruption, and find that its dynamical evolution is in qualitative agreement with simulations of idealized low-density cavities that are dominated by a large-scale Rayleigh-Taylor instability. The buoyant rising of the lobe does not create energetically significant small-scale chaotic motion in a volume-filling fashion, but rather a systematic upward motion in the wake of the lobe and a corresponding back-flow antiparallel to it. We find that, overall, 50 per cent of the injected energy ends up in material that is not part of the lobe, and about 25 per cent remains in the inner 100 kpc. We conclude that jet-inflated, buoyantly rising cavities drive systematic gas motions that play an important role in heating the central regions, while mixing of lobe material is subdominant. Encouragingly, the main mechanisms responsible for this energy deposition can be modelled already at resolutions within reach in future, high-resolution cosmological simulations of galaxy clusters.

Intractable diarrhoea of infancy and its management: modified cost effective treatment.

PubMed

Thapa, B R

1994-06-01

One-hundred-twenty infants under 1 year of age suffering from intractable diarrhoea were studied. They had received prior treatment in the form of antimicrobials (100 per cent), stool binding substance (50 percent), antimotility agents (50 per cent), and intravenous (IV) fluids (33 per cent). One-third of them had been hospitalised in peripheral hospitals. All of them had diarrhoea of more than 2 weeks' duration, protein energy malnutrition and were very ill. In addition vomiting, dehydration, fever, paralytic ileus, perianal excoriation and rectal prolapse were present in 44, 23, 33, 9, 47, and 3 per cent of the infants, respectively. Anaemia, multiple vitamin deficiencies, and pedal oedema were seen in 70, 10, and 3 per cent of infants, respectively. The infections documented were septicaemia (22 per cent), bronchopneumonia (6 per cent), meningitis (4 per cent), urinary tract infection (3 per cent) and acute supporative otitis media in 2 per cent of infants. Fifty-three per cent of infants had secondary lactose intolerance. Intolerance to milk protein, milk protein and soyabean and milk protein, as well as soyabean and chicken was seen in 4, 2, and 1 per cent cases, respectively. Aetiological agents isolated from stool culture were E. coli, (18 per cent), Klebsiella species (9 per cent), Shigella species (6 per cent), Salmonella typhimurium (2 per cent), Cholera mitschikom (1 per cent), Giardia lamblia (6 per cent), cryptosporidium (1 per cent), and E. histolytica (1 per cent). Candida albicans was grown in 18 per cent of infants. Pseudomembranous colitis was documented in 2 per cent cases.(ABSTRACT TRUNCATED AT 250 WORDS)

A new all-sky map of Galactic high-velocity clouds from the 21-cm HI4PI survey

NASA Astrophysics Data System (ADS)

Westmeier, Tobias

2018-02-01

High-velocity clouds (HVCs) are neutral or ionized gas clouds in the vicinity of the Milky Way that are characterized by high radial velocities inconsistent with participation in the regular rotation of the Galactic disc. Previous attempts to create a homogeneous all-sky H I map of HVCs have been hampered by a combination of poor angular resolution, limited surface brightness sensitivity and suboptimal sampling. Here, a new and improved H I map of Galactic HVCs based on the all-sky HI4PI survey is presented. The new map is fully sampled and provides significantly better angular resolution (16.2 versus 36 arcmin) and column density sensitivity (2.3 versus 3.7 × 1018 cm-2 at the native resolution) than the previously available LAB survey. The new HVC map resolves many of the major HVC complexes in the sky into an intricate network of narrow H I filaments and clumps that were not previously resolved by the LAB survey. The resulting sky coverage fraction of high-velocity H I emission above a column density level of 2 × 1018 cm-2 is approximately 15 per cent, which reduces to about 13 per cent when the Magellanic Clouds and other non-HVC emission are removed. The differential sky coverage fraction as a function of column density obeys a truncated power law with an exponent of -0.93 and a turnover point at about 5 × 1019 cm-2. H I column density and velocity maps of the HVC sky are made publicly available as FITS images for scientific use by the community.

X-ray constraints on the fraction of obscured active galactic nuclei at high accretion luminosities

NASA Astrophysics Data System (ADS)

Georgakakis, A.; Salvato, M.; Liu, Z.; Buchner, J.; Brandt, W. N.; Ananna, T. Tasnim; Schulze, A.; Shen, Yue; LaMassa, S.; Nandra, K.; Merloni, A.; McGreer, I. D.

2017-08-01

The wide-area XMM-XXL X-ray survey is used to explore the fraction of obscured active galactic nuclei (AGNs) at high accretion luminosities, LX(2-10 keV) ≳ 1044 erg s - 1, and out to redshift z ≈ 1.5. The sample covers an area of about 14 deg2 and provides constraints on the space density of powerful AGNs over a wide range of neutral hydrogen column densities extending beyond the Compton-thick limit, NH ≈ 1024 cm - 2. The fraction of obscured Compton-thin (NH = 1022-1024 cm - 2) AGNs is estimated to be ≈0.35 for luminosities LX(2-10 keV) > 1044 erg s - 1, independent of redshift. For less luminous sources, the fraction of obscured Compton-thin AGNs increases from 0.45 ± 0.10 at z = 0.25 to 0.75 ± 0.05 at z = 1.25. Studies that select AGNs in the infrared via template fits to the observed spectral energy distribution of extragalactic sources estimate space densities at high accretion luminosities consistent with the XMM-XXL constraints. There is no evidence for a large population of AGNs (e.g. heavily obscured) identified in the infrared and missed at X-ray wavelengths. We further explore the mid-infrared colours of XMM-XXL AGNs as a function of accretion luminosity, column density and redshift. The fraction of XMM-XXL sources that lie within the mid-infrared colour wedges defined in the literature to select AGNs is primarily a function of redshift. This fraction increases from about 20-30 per cent at z = 0.25 to about 50-70 per cent at z = 1.5.

High Quality Maize Centromere 10 Sequence Reveals Evidence of Frequent Recombination Events

PubMed Central

Wolfgruber, Thomas K.; Nakashima, Megan M.; Schneider, Kevin L.; Sharma, Anupma; Xie, Zidian; Albert, Patrice S.; Xu, Ronghui; Bilinski, Paul; Dawe, R. Kelly; Ross-Ibarra, Jeffrey; Birchler, James A.; Presting, Gernot G.

2016-01-01

The ancestral centromeres of maize contain long stretches of the tandemly arranged CentC repeat. The abundance of tandem DNA repeats and centromeric retrotransposons (CR) has presented a significant challenge to completely assembling centromeres using traditional sequencing methods. Here, we report a nearly complete assembly of the 1.85 Mb maize centromere 10 from inbred B73 using PacBio technology and BACs from the reference genome project. The error rates estimated from overlapping BAC sequences are 7 × 10−6 and 5 × 10−5 for mismatches and indels, respectively. The number of gaps in the region covered by the reassembly was reduced from 140 in the reference genome to three. Three expressed genes are located between 92 and 477 kb from the inferred ancestral CentC cluster, which lies within the region of highest centromeric repeat density. The improved assembly increased the count of full-length CR from 5 to 55 and revealed a 22.7 kb segmental duplication that occurred approximately 121,000 years ago. Our analysis provides evidence of frequent recombination events in the form of partial retrotransposons, deletions within retrotransposons, chimeric retrotransposons, segmental duplications including higher order CentC repeats, a deleted CentC monomer, centromere-proximal inversions, and insertion of mitochondrial sequences. Double-strand DNA break (DSB) repair is the most plausible mechanism for these events and may be the major driver of centromere repeat evolution and diversity. In many cases examined here, DSB repair appears to be mediated by microhomology, suggesting that tandem repeats may have evolved to efficiently repair frequent DSBs in centromeres. PMID:27047500

The fracture criticality of crustal rocks

NASA Astrophysics Data System (ADS)

Crampin, Stuart

1994-08-01

The shear-wave splitting observed along almost all shear-wave ray paths in the Earth's crust is interpreted as the effects of stress-aligned fluid-filled cracks, microcracks, and preferentially oriented pore space. Once away from the free surface, where open joints and fractures may lead to strong anisotropy of 10 per cent or greater, intact ostensibly unfractured crustal rock exhibits a limited range of shear-wave splitting from about 1.5 to 4.5 per cent differential shear-wave velocity anisotropy. Interpreting this velocity anisotropy as normalized crack densities, a factor of less than two in crack radius covers the range from the minimum 1.5 per cent anisotropy observed in intact rock to the 10 per cent observed in heavily cracked almost disaggregated near-surface rocks. This narrow range of crack dimensions and the pronounced effect on rock cohesion suggests that there is a state of fracture criticality at some level of anisotropy between 4.5 and 10 per cent marking the boundary between essentially intact, and heavily fractured rock. When the level of fracture criticality is exceeded, cracking is so severe that there is a breakdown in shear strength, the likelihood of progressive fracturing and the dispersal of pore fluids through enhanced permeability. The range of normalized crack dimensions below fracture criticality is so small in intact rock, that any modification to the crack geometry by even minor changes of conditions or minor deformation (particularly in the presence of high pore-fluid pressures) may change rock from being essentially intact (below fracture criticality) to heavily fractured (above fracture criticality). This recognition of the essential compliance of most crustal rocks, and its effect on shear-wave splitting, has implications for monitoring changes in any conditions affecting the rock mass. These include monitoring changes in reservoir evolution during hydrocarbon production and enhanced oil recovery, and in monitoring changes before and after earthquakes, amongst others.

Field evaluation of ZeroFly--an insecticide incorporated plastic sheeting against malaria vectors & its impact on malaria transmission in tribal area of northern Orissa.

PubMed

Sharma, S K; Upadhyay, A K; Haque, M A; Tyagi, P K; Mohanty, S S; Mittal, P K; Dash, A P

2009-10-01

Insecticide incorporated plastic sheeting is a new technology to control mosquitoes in emergency shelter places and also temporary habitations in different locations. Therefore, field studies were conducted to assess the efficacy of ZeroFly plastic sheeting treated with deltamethrin on prevailing disease vectors Anopheles culicifacies and An. fluviatilis and its impact on malaria transmission in one of the highly endemic areas of Orissa. The study was conducted in Birkera block of Sundargarh district, Orissa state. The study area comprised 3 villages, which were randomized as ZeroFly plastic sheet, untreated plastic sheet and no sheet area. ZeroFly plastic sheets and untreated plastic sheets were fixed in study and control villages respectively covering all the rooms in each household. Longitudinal studies were conducted on the bioefficacy with the help of cone bioassays, monitoring of the mosquito density through hand catch, floor sheet and exit trap collections and fortnightly domiciliary active surveillance in all the study villages. In ZeroFly plastic sheeting area, there was a significant reduction of 84.7 per cent in the entry rate of total mosquitoes in comparison to pre-intervention phase. There was 56.2 per cent immediate mortality in total mosquitoes in houses with ZeroFly sheeting. The overall feeding success rate of mosquitoes in the trial village was only 12.5 per cent in comparison to 49.7 and 51.1 per cent in villages with untreated plastic sheet and no sheet respectively. There was a significant reduction of 65.0 and 70.5 per cent in malaria incidence in ZeroFly plastic sheeting area as compared to untreated plastic sheet and no sheet area respectively. Our study showed that introduction of ZeroFly plastic sheets in a community-based intervention programme is operationally feasible to contain malaria especially in the high transmission difficult areas.

Effectiveness of 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in otomycosis patients: a randomised, controlled trial.

PubMed

Romsaithong, S; Tomanakan, K; Tangsawad, W; Thanaviratananich, S

2016-09-01

To compare the clinical effectiveness and adverse events for 3 per cent boric acid in 70 per cent alcohol versus 1 per cent clotrimazole solution in the treatment of otomycosis. A total of 120 otomycosis patients were randomly assigned to receive either 1 per cent clotrimazole solution (intervention group) or 3 per cent boric acid in 70 per cent alcohol (control group) at the Khon Kaen Hospital ENT out-patient department. Treatment effectiveness was determined based on the otomicroscopic absence of fungus one week after therapy, following a single application of treatment. After 1 week of treatment, there were data for 109 participants, 54 in the clotrimazole group and 55 in the boric acid group. The absolute difference in cure rates between 1 per cent clotrimazole solution and 3 per cent boric acid in 70 per cent alcohol was 17.9 per cent (95 per cent confidence interval, 2.3 to 33.5; p = 0.028) and the number needed to treat was 6 (95 per cent confidence interval, 3.0 to 43.4). Adverse events for the two agents were comparable. One per cent clotrimazole solution is more effective than 3 per cent boric acid in 70 per cent alcohol for otomycosis treatment.

Effects of particle packing on the sintered microstructure

NASA Astrophysics Data System (ADS)

Barringer, E. A.; Bowen, H. K.

1988-04-01

The sintering process is shown to be critically dependent on particle-packing density and porosity uniformity. Sintering experiments were conducted on compacts consisting of monodisperse, spherical TiO2 particles. Densification kinetics and microstructure evolution for two initial packing densities, 55% and 69% of theoretical, were investigated. The lower-density compacts sintered rapidly to theoretical density, yet improved particle-packing density and uniformity significantly enhanced densification.

How well does the Friends-of-Friends algorithm recover group properties from galaxy catalogues limited in both distance and luminosity?

NASA Astrophysics Data System (ADS)

Duarte, Manuel; Mamon, Gary A.

2014-05-01

The specific star formation rates of galaxies are influenced both by their mass and by their environment. Moreover, the mass function of groups and clusters serves as a powerful cosmological tool. It is thus important to quantify the accuracy to which group properties are extracted from redshift surveys. We test here the Friends-of-Friends (FoF) grouping algorithm, which depends on two linking lengths (LLs), plane-of-sky and line-of-sight (LOS), normalized to the mean nearest neighbour separation of field galaxies. We argue, on theoretical grounds, that LLs should be b⊥ ≃ 0.11, and b∥ ≈ 1.3 to recover 95 per cent of all galaxies with projected radii within the virial radius r200 and 95 per cent of the galaxies along the LOS. We then predict that 80 to 90 per cent of the galaxies in FoF groups should lie within their parent real-space groups (RSGs), defined within their virial spheres. We test the FoF extraction for 16 × 16 pairs of LLs, using subsamples of galaxies, doubly complete in distance and luminosity, of a flux-limited mock Sloan Digital Sky Survey (SDSS) galaxy catalogue. We find that massive RSGs are more prone to fragmentation, while the fragments typically have low estimated mass, with typically 30 per cent of groups of low and intermediate estimated mass being fragments. Group merging rises drastically with estimated mass. For groups of three or more galaxies, galaxy completeness and reliability are both typically better than 80 per cent (after discarding the fragments). Estimated masses of extracted groups are biased low, by up to a factor 4 at low richness, while the inefficiency of mass estimation improves from 0.85 dex to 0.2 dex when moving from low to high multiplicity groups. The optimal LLs depend on the scientific goal for the group catalogue. We propose b⊥ ≃ 0.07, with b∥ ≃ 1.1 for studies of environmental effects, b∥ ≃ 2.5 for cosmographic studies and b∥ ≃ 5 for followups of individual groups.

On the difficulties of detecting PP precursors

NASA Astrophysics Data System (ADS)

Lessing, Stephan; Thomas, Christine; Saki, Morvarid; Schmerr, Nicholas; Vanacore, Elizabeth

2015-06-01

The PP precursors are seismic waves that form from underside reflections of P waves off discontinuities in the upper mantle transition zone (MTZ). These seismic phases are used to map discontinuity topography, sharpness, and impedance contrasts; the resulting structural variations are then often interpreted as evidence for temperature and/or mineralogy variations within the mantle. The PP precursors as well as other seismic phases have been used to establish the global presence of seismic discontinuities at 410 and 660 km depth. Intriguingly, in more than 80 per cent of PP precursor observations the seismic wave amplitudes are significantly weaker than the amplitudes predicted by seismic reference models. Even more perplexing is the observation that 1-5 per cent of all earthquakes (which are 20-25 per cent of earthquakes with clear PP waveforms) do not show any evidence for the PP precursors from the discontinuities even in the presence of well-developed PP waveforms. Non-detections are found in six different data sets consisting of tens to hundreds of events. We use synthetic modelling to examine a suite of factors that could be responsible for the absence of the PP precursors. The take-off angles for PP and the precursors differ by only 1.2-1.5°; thus source-related complexity would affect PP and the precursors. A PP wave attenuated in the upper mantle would increase the relative amplitude of the PP precursors. Attenuation within the transition zone could reduce precursor amplitudes, but this would be a regional phenomenon restricted to particular source receiver geometries. We also find little evidence for deviations from the theoretical travel path of seismic rays expected for scattered arrivals. Factors that have a strong influence include the stacking procedures used in seismic array techniques in the presence of large, interfering phases, the presence of topography on the discontinuities on the order of tens of kilometres, and 3-D lateral heterogeneity in the velocity and density changes with depth across the transition zone. We also compare the observed precursors' amplitudes with seismic models from calculations of phase equilibria and find that a seismic velocity model derived from a pyrolite composition reproduces the data better than the currently available 1-D earth models. This largely owes to the pyrolite models producing a stronger minimum in the reflection coefficient across the epicentral distances where the reduction in amplitudes of the PP precursors is observed. To suppress the precursors entirely in a small subset of earthquakes, other effects, such as localized discontinuity topography and seismic signal processing effects are required in addition to the changed velocity model.

Epidemiological, clinical, haematological and biochemical characteristics of canine hypothyroidism.

PubMed

Dixon, R M; Reid, S W; Mooney, C T

1999-10-23

Hypothyroidism was diagnosed in 50 dogs and excluded in 86 dogs suspected of hypothyroidism, on the basis of the results of bovine thyrotropin response tests. Breed, pedigree, sex or neutering status did not significantly influence the likelihood of the dogs being hypothyroid. The hypothyroid dogs were significantly older than the non-hypothyroid dogs referred to the University of Glasgow during the same period. However, when dogs under two years of age were excluded from the statistical analyses there was no significant difference in age between the two groups. The most common clinical characteristics associated with hypothyroidism were metabolic signs (84 per cent of cases), particularly lethargy (76 per cent), obesity or weight gain (44 per cent), and exercise intolerance (24 per cent); and dermatological abnormalities (80 per cent), including alopecia (56 per cent), poor coat quality (30 per cent) and hyperpigmentation (20 per cent). When compared with the laboratory reference limits the most common biochemical and haematological abnormalities were increased concentrations of triglycerides (88 per cent), cholesterol (78 per cent), glucose (49 per cent), and fructosamine (43 per cent), and increased activities of creatine kinase (35 per cent), and decreased concentrations of inorganic phosphate (63 per cent), and a low red blood cell count (40 per cent). When compared with reference limits derived from the euthyroid dogs the most common abnormalities were increased concentrations of gamma-glutamyltransferase (21 per cent), cholesterol (18 per cent), and aspartate aminotransferase (15 per cent) and a decreased red blood cell count (29 per cent), and decreased neutrophils (18 per cent) and decreased activity of creatine kinase (15 per cent). Assessment of cholesterol, creatine kinase, aspartate aminotransferase, gamma-glutamyltransferase, and red blood cell and neutrophil counts may be particularly useful in distinguishing hypothyroid dogs from euthyroid animals with similar clinical signs.

A desert of gas giant planets beyond tens of au: from feast to famine

NASA Astrophysics Data System (ADS)

Nayakshin, Sergei

2017-09-01

It is argued that frequency of gravitational fragmentation of young massive discs around FGK stars may be much higher than commonly believed. Numerical simulations presented here show that survival of gas giant planets at large separations from their host stars is very model dependent. Low-mass clumps in slowly cooling discs are found to accrete gas very slowly and migrate inward very rapidly in the well-known type I regime (no gap open). They are either tidally disrupted or survive as planets inwards of about 10 au. In this regime, probability of clump survival at large separations is extremely low, perhaps as low as 0.001, requiring up to a dozen clumps per star early on to explain the observed population. In contrast, initially massive clumps or low-mass clumps born in rapidly cooling discs accrete gas rapidly. Opening deep gaps in the disc, they migrate in the much slower type II regime and are more likely to survive beyond tens of au. The frequency of disc fragmentation in this case is at the per cent level if the clump growth saturates at brown dwarf masses but may be close to 100 per cent if clumps evolve into low stellar mass companions. Taking these theoretical uncertainties into account, current observations limit the number of planet mass clumps hatched by young massive discs around FGK stars to between 0.01 and ˜10. A deeper theoretical understanding of such discs is needed to narrow this uncertainty down.

Improved Bayesian Infrasonic Source Localization for regional infrasound

DOE PAGES

Blom, Philip S.; Marcillo, Omar; Arrowsmith, Stephen J.

2015-10-20

The Bayesian Infrasonic Source Localization (BISL) methodology is examined and simplified providing a generalized method of estimating the source location and time for an infrasonic event and the mathematical framework is used therein. The likelihood function describing an infrasonic detection used in BISL has been redefined to include the von Mises distribution developed in directional statistics and propagation-based, physically derived celerity-range and azimuth deviation models. Frameworks for constructing propagation-based celerity-range and azimuth deviation statistics are presented to demonstrate how stochastic propagation modelling methods can be used to improve the precision and accuracy of the posterior probability density function describing themore » source localization. Infrasonic signals recorded at a number of arrays in the western United States produced by rocket motor detonations at the Utah Test and Training Range are used to demonstrate the application of the new mathematical framework and to quantify the improvement obtained by using the stochastic propagation modelling methods. Moreover, using propagation-based priors, the spatial and temporal confidence bounds of the source decreased by more than 40 per cent in all cases and by as much as 80 per cent in one case. Further, the accuracy of the estimates remained high, keeping the ground truth within the 99 per cent confidence bounds for all cases.« less

Simulating the physical properties of dark matter and gas inside the cosmic web

NASA Astrophysics Data System (ADS)

Dolag, K.; Meneghetti, M.; Moscardini, L.; Rasia, E.; Bonaldi, A.

2006-08-01

Using the results of a high-resolution, cosmological hydrodynamical re-simulation of a supercluster-like region, we investigate the physical properties of the gas located along the filaments and bridges which constitute the so-called cosmic web. First, we analyse the main characteristics of the density, temperature and velocity fields, which have quite different distributions, reflecting the complex dynamics of the structure-formation process. Then we quantify the signals which originate from the matter in the filaments by considering different observables. Inside the cosmic web, we find that the halo density is about 10-14 times larger than cosmic mean; the bremsstrahlung X-ray surface brightness reaches at most 10-16 erg s-1 cm-2 arcmin-2 the Compton-y parameter due to the thermal Sunyaev-Zel'dovich effect is about 10-6 the reduced shear produced by the weak lensing effect is ~0.01-0.02. These results confirm the difficulty of an observational detection of the cosmic web. Finally, we find that projection effects of the filamentary network can affect the estimates of the properties of single clusters, increasing their X-ray luminosity by less than 10 per cent and their central Compton-y parameter by up to 30 per cent.

Apoptosis and microvessel density in gastric cancer: correlation with tumor stage and prognosis.

PubMed

Aurello, Paolo; Bellagamba, Riccardo; Rossi Del Monte, Simone; D'Angelo, Francesco; Nigri, Giuseppe; Cicchini, Claudia; Ravaioli, Matteo; Ramacciato, Giovanni

2009-12-01

Gastric cancer remains one of the most common human malignancies with a poor prognosis. Apoptosis is known to be a programmed cell death and its inhibition is involved in the unregulated cellular growth that leads to neoplasms. Microvessel density (MVD) has been investigated as a promoting factor for angiogenesis with conflicting results about its relation to survival. The aim of our study was to search a correlation between these factors and some clinicopathological features and prognosis. Identification of apoptotic cells was performed applying the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling technique and recorded as apoptotic index (A.I.), whereas monoclonal antibodies were used for the study of MVD. A significant correlation was found between low and high A.I. and the subgroup of patients in Stages I and II (P < 0.02); 20 per cent of patients with a low A.I. showed an overall survival longer than 5 years versus 44 per cent of patients with an high A.I. (P = 0.041). High MVD was significantly related to the T stage (P = 0.036) and to a poorer 5-year overall survival (P < 0.05). Further studies are required to confirm the role of apoptosis and MVD in the development and progression of gastric cancer.

Are the infrared-faint radio sources pulsars?

NASA Astrophysics Data System (ADS)

Cameron, A. D.; Keith, M.; Hobbs, G.; Norris, R. P.; Mao, M. Y.; Middelberg, E.

2011-07-01

Infrared-faint radio sources (IFRS) are objects which are strong at radio wavelengths but undetected in sensitive Spitzer observations at infrared wavelengths. Their nature is uncertain and most have not yet been associated with any known astrophysical object. One possibility is that they are radio pulsars. To test this hypothesis we undertook observations of 16 of these sources with the Parkes Radio Telescope. Our results limit the radio emission to a pulsed flux density of less than 0.21 mJy (assuming a 50 per cent duty cycle). This is well below the flux density of the IFRS. We therefore conclude that these IFRS are not radio pulsars.

Female offspring desertion and male-only care increase with natural and experimental increase in food abundance

PubMed Central

Eldegard, Katrine; Sonerud, Geir A.

2009-01-01

In species with biparental care, one parent may escape the costs of parental care by deserting and leaving the partner to care for the offspring alone. A number of theoretical papers have suggested a link between uniparental offspring desertion and ecological factors, but empirical evidence is scarce. We investigated the relationship between uniparental desertion and food abundance in a natural population of Tengmalm's owl Aegolius funereus, both by means of a 5-year observational study and a 1-year experimental study. Parents and offspring were fitted with radio-transmitters in order to reveal the parental care strategy (i.e. care or desert) of individual parents, and to keep track of the broods post-fledging. We found that 70 per cent of the females from non-experimental nests deserted, while their partner continued to care for their joint offspring alone. Desertion rate was positively related to natural prey population densities and body reserves of the male partner. In response to food supplementation, a larger proportion of the females deserted, and females deserted the offspring at an earlier age. Offspring survival during the post-fledging period tended to be lower in deserted than in non-deserted broods. We argue that the most important benefit of deserting may be remating (sequential polyandry). PMID:19324835

Female offspring desertion and male-only care increase with natural and experimental increase in food abundance.

PubMed

Eldegard, Katrine; Sonerud, Geir A

2009-05-07

In species with biparental care, one parent may escape the costs of parental care by deserting and leaving the partner to care for the offspring alone. A number of theoretical papers have suggested a link between uniparental offspring desertion and ecological factors, but empirical evidence is scarce. We investigated the relationship between uniparental desertion and food abundance in a natural population of Tengmalm's owl Aegolius funereus, both by means of a 5-year observational study and a 1-year experimental study. Parents and offspring were fitted with radio-transmitters in order to reveal the parental care strategy (i.e. care or desert) of individual parents, and to keep track of the broods post-fledging. We found that 70 per cent of the females from non-experimental nests deserted, while their partner continued to care for their joint offspring alone. Desertion rate was positively related to natural prey population densities and body reserves of the male partner. In response to food supplementation, a larger proportion of the females deserted, and females deserted the offspring at an earlier age. Offspring survival during the post-fledging period tended to be lower in deserted than in non-deserted broods. We argue that the most important benefit of deserting may be remating (sequential polyandry).

Influence of particle size distribution on nanopowder cold compaction processes

NASA Astrophysics Data System (ADS)

Boltachev, G.; Volkov, N.; Lukyashin, K.; Markov, V.; Chingina, E.

2017-06-01

Nanopowder uniform and uniaxial cold compaction processes are simulated by 2D granular dynamics method. The interaction of particles in addition to wide-known contact laws involves the dispersion forces of attraction and possibility of interparticle solid bridges formation, which have a large importance for nanopowders. Different model systems are investigated: monosized systems with particle diameter of 10, 20 and 30 nm; bidisperse systems with different content of small (diameter is 10 nm) and large (30 nm) particles; polydisperse systems corresponding to the log-normal size distribution law with different width. Non-monotone dependence of compact density on powder content is revealed in bidisperse systems. The deviations of compact density in polydisperse systems from the density of corresponding monosized system are found to be minor, less than 1 per cent.

Research in higher surgical training--the West Midlands view.

PubMed

Kmiot, W A; Neoptolemos, J P; Temple, J G

1993-09-01

A questionnaire on the role of research in higher surgical training was posted to all in-post NHS Consultants (n = 96) and Higher Surgical Trainees (n = 42) in the West Midlands Region. Replies were received from 80 consultants (83 per cent) and 37 trainees (88 per cent). Over 95 per cent of responders had undertaken some research activity previously. The vast majority of consultants (90 per cent) and trainees (95 per cent) thought that their research period had been beneficial; most would undertake research again even if not essential for higher surgical training (consultants 80 per cent, trainees 70 per cent). Research was felt to be essential for all trainees by 50 per cent of respondents in both groups; 78 per cent of consultants and 86 per cent of trainees also thought that all potential academics should obtain a degree by thesis. Most of the study participants thought that the appropriate time for research activity was as a post-FRCS registrar (consultants 72 per cent, trainees 80 per cent); 80 per cent of consultants and 67 per cent of trainees felt that this research period should be funded by the NHS. A planned, supervised and funded one-year period of research was favoured by the majority of consultants (54 per cent) and trainees (73 per cent) for non-academic general surgical trainees in the future.

Major merging history in CANDELS. I. Evolution of the incidence of massive galaxy-galaxy pairs from z = 3 to z ˜ 0

NASA Astrophysics Data System (ADS)

Mantha, Kameswara Bharadwaj; McIntosh, Daniel H.; Brennan, Ryan; Ferguson, Henry C.; Kodra, Dritan; Newman, Jeffrey A.; Rafelski, Marc; Somerville, Rachel S.; Conselice, Christopher J.; Cook, Joshua S.; Hathi, Nimish P.; Koo, David C.; Lotz, Jennifer M.; Simmons, Brooke D.; Straughn, Amber N.; Snyder, Gregory F.; Wuyts, Stijn; Bell, Eric F.; Dekel, Avishai; Kartaltepe, Jeyhan; Kocevski, Dale D.; Koekemoer, Anton M.; Lee, Seong-Kook; Lucas, Ray A.; Pacifici, Camilla; Peth, Michael A.; Barro, Guillermo; Dahlen, Tomas; Finkelstein, Steven L.; Fontana, Adriano; Galametz, Audrey; Grogin, Norman A.; Guo, Yicheng; Mobasher, Bahram; Nayyeri, Hooshang; Pérez-González, Pablo G.; Pforr, Janine; Santini, Paola; Stefanon, Mauro; Wiklind, Tommy

2018-04-01

The rate of major galaxy-galaxy merging is theoretically predicted to steadily increase with redshift during the peak epoch of massive galaxy development (1 ≤ z ≤ 3). We use close-pair statistics to objectively study the incidence of massive galaxies (stellar M1 > 2 × 1010 M⊙) hosting major companions (1 ≤ M1/M2 ≤ 4; i.e. <4:1) at six epochs spanning 0 < z < 3. We select companions from a nearly complete, mass-limited (≥5 × 109 M⊙) sample of 23 696 galaxies in the five Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey fields and the Sloan Digital Sky Survey. Using 5-50 kpc projected separation and close redshift proximity criteria, we find that the major companion fraction fmc(z) based on stellar mass-ratio (MR) selection increases from 6 per cent (z ˜ 0) to 16 per cent (z ˜ 0.8), then turns over at z ˜ 1 and decreases to 7 per cent (z ˜ 3). Instead, if we use a major F160W flux-ratio (FR) selection, we find that fmc(z) increases steadily until z = 3 owing to increasing contamination from minor (MR > 4:1) companions at z > 1. We show that these evolutionary trends are statistically robust to changes in companion proximity. We find disagreements between published results are resolved when selection criteria are closely matched. If we compute merger rates using constant fraction-to-rate conversion factors (Cmerg,pair = 0.6 and Tobs,pair = 0.65 Gyr), we find that MR rates disagree with theoretical predictions at z > 1.5. Instead, if we use an evolving Tobs,pair(z) ∝ (1 + z)-2 from Snyder et al., our MR-based rates agree with theory at 0 < z < 3. Our analysis underscores the need for detailed calibration of Cmerg,pair and Tobs,pair as a function of redshift, mass, and companion selection criteria to better constrain the empirical major merger history.

10C survey of radio sources at 15.7 GHz - II. First results

NASA Astrophysics Data System (ADS)

AMI Consortium; Davies, Mathhew L.; Franzen, Thomas M. O.; Waldram, Elizabeth M.; Grainge, Keith J. B.; Hobson, Michael P.; Hurley-Walker, Natasha; Lasenby, Anthony; Olamaie, Malak; Pooley, Guy G.; Riley, Julia M.; Rodríguez-Gonzálvez, Carmen; Saunders, Richard D. E.; Scaife, Anna M. M.; Schammel, Michel P.; Scott, Paul F.; Shimwell, Timothy W.; Titterington, David J.; Zwart, Jonathan T. L.

2011-08-01

In a previous paper (Paper I), the observational, mapping and source-extraction techniques used for the Tenth Cambridge (10C) Survey of Radio Sources were described. Here, the first results from the survey, carried out using the Arcminute Microkelvin Imager Large Array (LA) at an observing frequency of 15.7 GHz, are presented. The survey fields cover an area of ≈27 deg2 to a flux-density completeness of 1 mJy. Results for some deeper areas, covering ≈12 deg2, wholly contained within the total areas and complete to 0.5 mJy, are also presented. The completeness for both areas is estimated to be at least 93 per cent. The 10C survey is the deepest radio survey of any significant extent (≳0.2 deg2) above 1.4 GHz. The 10C source catalogue contains 1897 entries and is available online. The source catalogue has been combined with that of the Ninth Cambridge Survey to calculate the 15.7-GHz source counts. A broken power law is found to provide a good parametrization of the differential count between 0.5 mJy and 1 Jy. The measured source count has been compared with that predicted by de Zotti et al. - the model is found to display good agreement with the data at the highest flux densities. However, over the entire flux-density range of the measured count (0.5 mJy to 1 Jy), the model is found to underpredict the integrated count by ≈30 per cent. Entries from the source catalogue have been matched with those contained in the catalogues of the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-cm survey (both of which have observing frequencies of 1.4 GHz). This matching provides evidence for a shift in the typical 1.4-GHz spectral index to 15.7-GHz spectral index of the 15.7-GHz-selected source population with decreasing flux density towards sub-mJy levels - the spectra tend to become less steep. Automated methods for detecting extended sources, developed in Paper I, have been applied to the data; ≈5 per cent of the sources are found to be extended relative to the LA-synthesized beam of ≈30 arcsec. Investigations using higher resolution data showed that most of the genuinely extended sources at 15.7 GHz are classical doubles, although some nearby galaxies and twin-jet sources were also identified.

Effects of high-frequency understorey fires on woody plant regeneration in southeastern Amazonian forests

PubMed Central

Balch, Jennifer K.; Massad, Tara J.; Brando, Paulo M.; Nepstad, Daniel C.; Curran, Lisa M.

2013-01-01

Anthropogenic understorey fires affect large areas of tropical forest, yet their effects on woody plant regeneration post-fire remain poorly understood. We examined the effects of repeated experimental fires on woody stem (less than 1 cm at base) mortality, recruitment, species diversity, community similarity and regeneration mode (seed versus sprout) in Mato Grosso, Brazil. From 2004 to 2010, forest plots (50 ha) were burned twice (B2) or five times (B5), and compared with an unburned control (B0). Stem density recovered within a year after the first burn (initial density: 12.4–13.2 stems m−2), but after 6 years, increased mortality and decreased regeneration—primarily of seedlings—led to a 63 per cent and 85 per cent reduction in stem density in B2 and B5, respectively. Seedlings and sprouts across plots in 2010 displayed remarkable community similarity owing to shared abundant species. Although the dominant surviving species were similar across plots, a major increase in sprouting occurred—almost three- and fourfold greater in B2 and B5 than in B0. In B5, 29 species disappeared and were replaced by 11 new species often present along fragmented forest edges. By 2010, the annual burn regime created substantial divergence between the seedling community and the initial adult tree community (greater than or equal to 20 cm dbh). Increased droughts and continued anthropogenic ignitions associated with frontier land uses may promote high-frequency fire regimes that may substantially alter regeneration and therefore successional processes. PMID:23610167

Fast radio bursts: the observational case for a Galactic origin

NASA Astrophysics Data System (ADS)

Maoz, Dan; Loeb, Abraham; Shvartzvald, Yossi; Sitek, Monika; Engel, Michael; Kiefer, Flavien; Kiraga, Marcin; Levi, Amir; Mazeh, Tsevi; Pawlak, Michał; Rich, R. Michael; Tal-Or, Lev; Wyrzykowski, Lukasz

2015-12-01

There are by now ten published detections of fast radio bursts (FRBs) - single bright GHz-band millisecond pulses of unknown origin. Proposed explanations cover a broad range from exotic processes at cosmological distances to atmospheric and terrestrial sources. Loeb, Maoz, and Shvartzvald have previously suggested that FRB sources could be nearby flare stars, and pointed out the presence of a W-UMa-type contact binary within the beam of one out of three FRB fields that they examined. To further test the flare-star hypothesis, we use time-domain optical photometry and spectroscopy, and now find possible flare stars in additional FRB fields, with one to three such cases among all eight FRB fields studied. We evaluate the chance probabilities of these possible associations to be in the range ˜0.1 per cent to 9 per cent, depending on the input assumptions. Further, we re-analyse the probability that two FRBs recently discovered three years apart within the same radio beam are unrelated. Contrary to other claims, we conclude with 99 per cent confidence that the two events are from the same repeating source. The different dispersion measures between the two bursts then rule out a cosmological intergalactic-medium origin for the dispersion measure, but are consistent with the flare-star scenario with a varying plasma blanket between bursts. Finally, we review some theoretical objections that have been raised against a local flare-star FRB origin, and show that they are incorrect.

Development of nursing research in Jordan (1986-2012).

PubMed

Khalaf, I

2013-12-01

To provide an overview of nursing research in Jordan based on the topic researched, source and setting of data collection, methodology, theoretical framework used and source of funding. Nursing research contributes to nursing education, clinical practice, health policy and the establishment of nursing research priorities in Jordan to guide future research. Databases such as MEDLINE, CINAHL, Google Scholar, PubMed and national sources were searched for published articles related to nursing in Jordan through a range of keywords. Articles were included in the analysis if they were published in English or Arabic through December 2012. The search resulted in the identification of 999 publications, from which 462 articles met the inclusion criteria and were included in the review. The highest percentage of studies (23% of articles) focused on nursing management issues. Forty-four per cent were conducted in a hospital setting; only six studies used a nursing theory. Seventy-seven per cent of the studies were quantitative and 29.0% were funded mostly by universities. Twenty-one per cent were not directly related to improving nursing education or practice in Jordan. A Jordanian Database for nursing research was developed as a result of this review. Jordanian nurses have slowly started to build nursing research, the real nursing research work in Jordan started with the return of the first PhD graduate to Jordan in 1986. Jordanian nurses in collaboration with international colleagues were motivated to publish research and build the body of nursing knowledge. © 2013 International Council of Nurses.

Trampoline-related injuries.

PubMed

Larson, B J; Davis, J W

1995-08-01

Two hundred and seventeen patients who had sustained an injury during the recreational use of a trampoline were managed in the emergency room of Logan Regional Hospital in Logan, Utah, from January 1991 through December 1992. We retrospectively reviewed the charts and radiographs of these patients to categorize the injuries. Additional details regarding the injuries of seventy-two patients (33 per cent) were obtained by means of a telephone interview with use of a questionnaire. The injuries occurred from February through November, with the peak incidence in July. The patients were eighteen months to forty-five years old (average, ten years old); ninety-four patients (43 per cent) were five to nine years old. Eighty-four patients (39 per cent) sustained a fracture; fifty-four (25 per cent), a sprain or strain; forty-five (21 per cent), a laceration; and thirty-four (16 per cent), a contusion. Fifty-seven injuries (26 per cent) involved the elbow or forearm; forty-six (21 per cent), the head or neck; forty (18 per cent), the ankle or foot; thirty-three (15 per cent), the knee or leg; nineteen (9 per cent), the trunk or back; thirteen (6 per cent), the shoulder or arm; and nine (4 per cent), the wrist or hand. Thirteen patients (6 per cent) had a back injury, but none of them had a permanent neurological deficit. One patient who had an ocular injury was transferred to a tertiary care center. One hundred and fifty-six patients (72 per cent) were evaluated radiographically, fifteen (7 per cent) were admitted to the hospital, and thirteen (6 per cent) had an operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Observational selection biases in time-delay strong lensing and their impact on cosmography

NASA Astrophysics Data System (ADS)

Collett, Thomas E.; Cunnington, Steven D.

2016-11-01

Inferring cosmological parameters from time-delay strong lenses requires a significant investment of telescope time; it is therefore tempting to focus on the systems with the brightest sources, the highest image multiplicities and the widest image separations. We investigate if this selection bias can influence the properties of the lenses studied and the cosmological parameters inferred. Using an ellipsoidal power-law deflector population, we build a sample of double- and quadruple-image systems. Assuming reasonable thresholds on image separation and flux, based on current lens monitoring campaigns, we find that the typical density profile slopes of monitorable lenses are significantly shallower than the input ensemble. From a sample of quads, we find that this selection function can introduce a 3.5 per cent bias on the inferred time-delay distances if the properties of the input ensemble are (incorrectly) used as priors on the lens model. This bias remains at the 2.4 per cent level when high-resolution imaging of the quasar host is used to precisely infer the properties of individual lenses. We also investigate if the lines of sight for monitorable strong lenses are biased. The expectation value for the line-of-sight convergence is increased by 0.009 (0.004) for quads (doubles) implying a 0.9 per cent (0.4 per cent) bias on H0. We therefore conclude that whilst the properties of typical quasar lenses and their lines of sight do deviate from the global population, the total magnitude of this effect is likely to be a subdominant effect for current analyses, but has the potential to be a major systematic for samples of ˜25 or more lenses.

The SuperCOSMOS all-sky galaxy catalogue

NASA Astrophysics Data System (ADS)

Peacock, J. A.; Hambly, N. C.; Bilicki, M.; MacGillivray, H. T.; Miller, L.; Read, M. A.; Tritton, S. B.

2016-10-01

We describe the construction of an all-sky galaxy catalogue, using SuperCOSMOS scans of Schmidt photographic plates from the UK Schmidt Telescope and Second Palomar Observatory Sky Survey. The photographic photometry is calibrated using Sloan Digital Sky Survey data, with results that are linear to 2 per cent or better. All-sky photometric uniformity is achieved by matching plate overlaps and also by requiring homogeneity in optical-to-2MASS colours, yielding zero-points that are uniform to 0.03 mag or better. The typical AB depths achieved are BJ < 21, RF < 19.5 and IN < 18.5, with little difference between hemispheres. In practice, the IN plates are shallower than the BJ and RF plates, so for most purposes we advocate the use of a catalogue selected in these two latter bands. At high Galactic latitudes, this catalogue is approximately 90 per cent complete with 5 per cent stellar contamination; we quantify how the quality degrades towards the Galactic plane. At low latitudes, there are many spurious galaxy candidates resulting from stellar blends: these approximately match the surface density of true galaxies at |b| = 30°. Above this latitude, the catalogue limited in BJ and RF contains in total about 20 million galaxy candidates, of which 75 per cent are real. This contamination can be removed, and the sky coverage extended, by matching with additional data sets. This SuperCOSMOS catalogue has been matched with 2MASS and with WISE, yielding quasi-all-sky samples of respectively 1.5 million and 18.5 million galaxies, to median redshifts of 0.08 and 0.20. This legacy data set thus continues to offer a valuable resource for large-angle cosmological investigations.

Baseline-dependent averaging in radio interferometry

NASA Astrophysics Data System (ADS)

Wijnholds, S. J.; Willis, A. G.; Salvini, S.

2018-05-01

This paper presents a detailed analysis of the applicability and benefits of baseline-dependent averaging (BDA) in modern radio interferometers and in particular the Square Kilometre Array. We demonstrate that BDA does not affect the information content of the data other than a well-defined decorrelation loss for which closed form expressions are readily available. We verify these theoretical findings using simulations. We therefore conclude that BDA can be used reliably in modern radio interferometry allowing a reduction of visibility data volume (and hence processing costs for handling visibility data) by more than 80 per cent.

Spray-freeze-drying of nanosuspensions: the manufacture of insulin particles for needle-free ballistic powder delivery

PubMed Central

Schiffter, Heiko; Condliffe, Jamie; Vonhoff, Sebastian

2010-01-01

The feasibility of preparing microparticles with high insulin loading suitable for needle-free ballistic drug delivery by spray-freeze-drying (SFD) was examined in this study. The aim was to manufacture dense, robust particles with a diameter of around 50 µm, a narrow size distribution and a high content of insulin. Atomization using ultrasound atomizers showed improved handling of small liquid quantities as well as narrower droplet size distributions over conventional two-fluid nozzle atomization. Insulin nanoparticles were produced by SFD from solutions with a low solid content (<10 mg ml−1) and subsequent ultra-turrax homogenization. To prepare particles for needle-free ballistic injection, the insulin nanoparticles were suspended in matrix formulations with a high excipient content (>300 mg ml−1) consisting of trehalose, mannitol, dextran (10 kDa) and dextran (150 kDa) (abbreviated to TMDD) in order to maximize particle robustness and density after SFD. With the increase in insulin content, the viscosity of the nanosuspensions increased. Liquid atomization was possible up to a maximum of 250 mg of nano-insulin suspended in a 1.0 g matrix. However, if a narrow size distribution with a good correlation between theoretical and measurable insulin content was desired, no more than 150 mg nano-insulin could be suspended per gram of matrix formulation. Particles were examined by laser light diffraction, scanning electron microscopy and tap density testing. Insulin stability was assessed using size exclusion chromatography (SEC), reverse phase chromatography and Fourier transform infrared (FTIR) spectroscopy. Densification of the particles could be achieved during primary drying if the product temperature (Tprod) exceeded the glass transition temperature of the freeze concentrate (Tg′) of −29.4°C for TMDD (3∶3∶3∶1) formulations. Particles showed a collapsed and wrinkled morphology owing to viscous flow of the freeze concentrate. With increasing insulin loading, the d (v, 0.5) of the SFD powders increased and particle size distributions got wider. Insulin showed a good stability during the particle formation process with a maximum decrease in insulin monomer of only 0.123 per cent after SFD. In accordance with the SEC data, FTIR analysis showed only a small increase in the intermolecular β-sheet of 0.4 per cent after SFD. The good physical stability of the polydisperse particles made them suitable for ballistic injection into tissue-mimicking agar hydrogels, showing a mean penetration depth of 251.3 ± 114.7 µm. PMID:20519207

Racism, ethnic density and psychological well-being through adolescence: evidence from the Determinants of Adolescent Social well-being and Health longitudinal study

PubMed Central

Astell-Burt, Thomas; Maynard, Maria J.; Lenguerrand, Erik; Harding, Seeromanie

2012-01-01

Objective. To investigate the effect of racism, own-group ethnic density, diversity and deprivation on adolescent trajectories in psychological well-being. Design. Multilevel models were used in longitudinal analysis of psychological well-being (total difficulties score (TDS) from Goodman's Strengths and Difficulties Questionnaire, higher scores correspond to greater difficulties) for 4782 adolescents aged 11–16 years in 51 London (UK) schools. Individual level variables included ethnicity, racism, gender, age, migrant generation, socioeconomic circumstances, family type and indicators of family interactions (shared activities, perceived parenting). Contextual variables were per cent eligible for free school-meals, neighbourhood deprivation, per cent own-group ethnic density, and ethnic diversity. Results. Ethnic minorities were more likely to report racism than Whites. Ethnic minority boys (except Indian boys) and Indian girls reported better psychological well-being throughout adolescence compared to their White peers. Notably, lowest mean TDS scores were observed for Nigerian/Ghanaian boys, among whom the reporting of racism increased with age. Adjusted for individual characteristics, psychological well-being improved with age across all ethnic groups. Racism was associated with poorer psychological well-being trajectories for all ethnic groups (p <0.001), reducing with age. For example, mean difference in TDS (95% confidence interval) between boys who experienced racism and those who did not at age 12 years = 1.88 (+1.75 to + 2.01); at 16 years = +1.19 (+1.07 to +1.31). Less racism was generally reported in schools and neighbourhoods with high than low own-group density. Own ethnic density and diversity were not consistently associated with TDS for any ethnic group. Living in more deprived neighbourhoods was associated with poorer psychological well-being for Whites and Black Caribbeans (p <0.05). Conclusion. Racism, but not ethnic density and deprivation in schools or neighbourhoods, was an important influence on psychological well-being. However, exposure to racism did not explain the advantage in psychological well-being of ethnic minority groups over Whites. PMID:22332834

An Evaluation of Parastomal Hernia Repair Using the Americas Hernia Society Quality Collaborative.

PubMed

Fox, Sarah S; Janczyk, Randy; Warren, Jeremy A; Carbonell, Alfredo M; Poulose, Benjamin K; Rosen, Michael J; Hope, William W

2017-08-01

The purpose of this review was to evaluate outcomes relating to parastomal hernia repair. Data from the Americas Hernia Society Quality Collaborative were used to identify patients undergoing parastomal hernia repair from 2013 to 2016. Parastomal hernia repairs were compared with other repairs using Pearson's test and Wilcoxon test with a P value <0.05 considered significant. Parastomal hernia repairs were performed in 311 patients. Techniques of repair include open in 85 per cent and laparoscopic in 15 per cent. Mesh was used in 92 per cent with keyhole in 34 per cent, flat mesh in 33 per cent, and Sugarbaker in 25 per cent. Mesh types were permanent synthetic in 79 per cent, biologic in 13 per cent, absorbable synthetic in 6 per cent, and hybrid synthetic/biologic in 2 per cent. Most common location for mesh was sublay in 84 per cent followed by onlay in 14 per cent and inlay in 2 per cent with 59 per cent of patients undergoing a myofascial release. Ostomy disposition included ostomy left in situ (47%), moved to a new site (18%), taken down (22%), and rematured in same location in (13%). Outcomes related to parastomal hernia repair included 10 per cent surgical site infection, 24 per cent surgical site occurrence, and 12 per cent surgical site occurrences requiring procedural interventions with a 13 per cent readmission rate and 6 per cent reoperation rate. When comparing parastomal hernias with other ventral hernia repairs, parastomal hernias had a significantly higher surgical site infection, surgical site occurrence, surgical site occurrences requiring procedural intervention, readmission, reoperation rate, and length of stay, and were less commonly performed laparoscopically (P < 0.05). Most parastomal hernias are being repaired open with synthetic mesh in the sublay position. Less favorable outcomes of parastomal hernia repair when compared with other ventral hernia repairs are likely related to the complexity of parastomal hernia repair.

The nature of assembly bias - III. Observational properties

NASA Astrophysics Data System (ADS)

Lacerna, Ivan; Padilla, Nelson; Stasyszyn, Federico

2014-10-01

We analyse galaxies in groups in the Sloan Digital Sky Survey (SDSS) and find a weak but significant assembly-type bias, where old central galaxies have a higher clustering amplitude (61 ± 9 per cent) at scales >1 h-1 Mpc than young central galaxies of equal host halo mass (Mh ˜ 1011.8 h- 1 M⊙). The observational sample is volume limited out to z = 0.1 with Mr - 5 log (h) ≤ -19.6. We construct a mock catalogue of galaxies that shows a similar signal of assembly bias (46 ± 9 per cent) at the same halo mass. We then adapt the model presented by Lacerna & Padilla (Paper I) to redefine the overdensity peak height, which traces the assembly bias such that galaxies in equal density peaks show the same clustering regardless of their stellar age, but this time using observational features such as a flux limit. The proxy for peak height, which is proposed as a better alternative than the virial mass, consists in the total mass given by the mass of neighbour host haloes in cylinders centred at each central galaxy. The radius of the cylinder is parameterized as a function of stellar age and virial mass. The best-fitting sets of parameters that make the assembly bias signal lower than 5-15 per cent for both SDSS and mock central galaxies are similar. The idea behind the parameterization is not to minimize the bias, but it is to use this method to understand the physical features that produce the assembly bias effect. Even though the tracers of the density field used here differ significantly from those used in Paper I, our analysis of the simulated catalogue indicates that the different tracers produce correlated proxies, and therefore the reason behind assembly bias is the crowding of peaks in both simulations and the SDSS.

The divergent fates of primitive hydrospheric water on Earth and Mars

NASA Astrophysics Data System (ADS)

Wade, Jon; Dyck, Brendan; Palin, Richard M.; Moore, James D. P.; Smye, Andrew J.

2017-12-01

Despite active transport into Earth’s mantle, water has been present on our planet’s surface for most of geological time. Yet water disappeared from the Martian surface soon after its formation. Although some of the water on Mars was lost to space via photolysis following the collapse of the planet’s magnetic field, the widespread serpentinization of Martian crust suggests that metamorphic hydration reactions played a critical part in the sequestration of the crust. Here we quantify the relative volumes of water that could be removed from each planet’s surface via the burial and metamorphism of hydrated mafic crusts, and calculate mineral transition-induced bulk-density changes at conditions of elevated pressure and temperature for each. The metamorphic mineral assemblages in relatively FeO-rich Martian lavas can hold about 25 per cent more structurally bound water than those in metamorphosed terrestrial basalts, and can retain it at greater depths within Mars. Our calculations suggest that in excess of 9 per cent by volume of the Martian mantle may contain hydrous mineral species as a consequence of surface reactions, compared to about 4 per cent by volume of Earth’s mantle. Furthermore, neither primitive nor evolved hydrated Martian crust show noticeably different bulk densities compared to their anhydrous equivalents, in contrast to hydrous mafic terrestrial crust, which transforms to denser eclogite upon dehydration. This would have allowed efficient overplating and burial of early Martian crust in a stagnant-lid tectonic regime, in which the lithosphere comprised a single tectonic plate, with only the warmer, lower crust involved in mantle convection. This provided an important sink for hydrospheric water and a mechanism for oxidizing the Martian mantle. Conversely, relatively buoyant mafic crust and hotter geothermal gradients on Earth reduced the potential for upper-mantle hydration early in its geological history, leading to water being retained close to its surface, and thus creating conditions conducive for the evolution of complex multicellular life.

The divergent fates of primitive hydrospheric water on Earth and Mars.

PubMed

Wade, Jon; Dyck, Brendan; Palin, Richard M; Moore, James D P; Smye, Andrew J

2017-12-20

Despite active transport into Earth's mantle, water has been present on our planet's surface for most of geological time. Yet water disappeared from the Martian surface soon after its formation. Although some of the water on Mars was lost to space via photolysis following the collapse of the planet's magnetic field, the widespread serpentinization of Martian crust suggests that metamorphic hydration reactions played a critical part in the sequestration of the crust. Here we quantify the relative volumes of water that could be removed from each planet's surface via the burial and metamorphism of hydrated mafic crusts, and calculate mineral transition-induced bulk-density changes at conditions of elevated pressure and temperature for each. The metamorphic mineral assemblages in relatively FeO-rich Martian lavas can hold about 25 per cent more structurally bound water than those in metamorphosed terrestrial basalts, and can retain it at greater depths within Mars. Our calculations suggest that in excess of 9 per cent by volume of the Martian mantle may contain hydrous mineral species as a consequence of surface reactions, compared to about 4 per cent by volume of Earth's mantle. Furthermore, neither primitive nor evolved hydrated Martian crust show noticeably different bulk densities compared to their anhydrous equivalents, in contrast to hydrous mafic terrestrial crust, which transforms to denser eclogite upon dehydration. This would have allowed efficient overplating and burial of early Martian crust in a stagnant-lid tectonic regime, in which the lithosphere comprised a single tectonic plate, with only the warmer, lower crust involved in mantle convection. This provided an important sink for hydrospheric water and a mechanism for oxidizing the Martian mantle. Conversely, relatively buoyant mafic crust and hotter geothermal gradients on Earth reduced the potential for upper-mantle hydration early in its geological history, leading to water being retained close to its surface, and thus creating conditions conducive for the evolution of complex multicellular life.

Deep Chandra Observation and Numerical Studies of the Nearest Cluster Cold Front in the Sky

NASA Technical Reports Server (NTRS)

Werner, N.; ZuHone, J. A.; Zhuravleva, I.; Ichinohe, Y.; Simionescu, A.; Allen, S. W.; Markevitch, M.; Fabian, A. C.; Keshet, U.; Roediger, E.;

Role of fat metabolism in exercise.

PubMed

Askew, E W

1984-07-01

Fat and carbohydrate are the two major energy sources used during exercise. Either source can predominate, depending upon the duration and intensity of exercise, degree of prior physical conditioning, and the composition of the diet consumed in the days prior to a bout of exercise. Fatty acid oxidation can contribute 50 to 60 per cent of the energy expenditure during a bout of low intensity exercise of long duration. Strenuous submaximal exercise requiring 65 to 80 per cent of VO2 max will utilize less fat (10 to 45 per cent of the energy expended). Exercise training is accompanied by metabolic adaptations that occur in skeletal muscle and adipose tissue and that facilitate a greater delivery and oxidation of fatty acids during exercise. The trained state is characterized by an increased flux of fatty acids through smaller pools of adipose tissue energy. This is reflected by smaller, more metabolically active adipose cells in smaller adipose tissue depots. Peak blood concentrations of free fatty acids and ketone bodies are lower during and following exercise in trained individuals, probably due to increased capacity of the skeletal musculature to oxidize these energy sources. Trained individuals oxidize more fat and less carbohydrate than untrained subjects when performing submaximal work of the same absolute intensity. This increased capacity to utilize energy from fat conserves crucial muscle and liver glycogen stores and can contribute to increased endurance. Further benefits of the enhanced lipid metabolism accompanying chronic aerobic exercise training are decreased cardiac risk factors. Exercise training results in lower blood cholesterol and triglycerides and increased high density lipoprotein cholesterol. High-fat diets are not recommended because of their association with atherosclerotic heart disease. Recent evidence suggests that low-fat high-carbohydrate diets may increase blood triglycerides and reduce high density lipoproteins. This suggests that the chronic ingestion of diets that are extreme in their composition of either fat or carbohydrate should be approached with caution in health-conscious athletes, as well as in sedentary individuals.

Benchmarking welfare indicators in 73 free-stall dairy farms in north-western Spain

PubMed Central

Trillo, Yolanda; Quintela, Luis Angel; Barrio, Mónica; Becerra, Juan José; Peña, Ana Isabel; Vigo, Marcos; Garcia Herradon, Pedro

2017-01-01

The aim of this study was to describe the status of body condition score (BCS), hock injuries prevalence, locomotion and body hygiene score as animal welfare measures in 73 free-stall dairy cattle farms in Lugo (Spain). A benchmarking process was established across farms: (1) the animal-based indicators were ordered from low to high values; (2) The farms were classified into three categories based on the number of indicators within less than the 25th percentile, 25th to 75th percentile and above the 75th percentile. The median prevalence of unsuitable BCS, hock injuries and clinical lameness was (median (range)) 51.7 per cent (13.3 to 89.5 per cent), 40.0 per cent (7.0per cent to 100 per cent) and 9.0 per cent (0per cent to 60.0 per cent) respectively. The dirtiness of the cow’s coat had a high prevalence (73.0 per cent (37.5per cent to 100 per cent)). Most farms did not display consistently good or poor animal-based indicators and each farm had its own set of strong and weak points. Moreover, facilities design and management practices were described to understand source of the observations made of the cows. The incidence of overstocking was 31.5 per cent for stalls and 26.0 per cent for headlocks. The front lunge space was reduced (<90 cm) on most dairies (90.4 per cent). Signs of poor natural ventilation (cobwebs or humidity on the roof) and ammonia odour were observed on 32.8 per cent and 85.0 per cent of the barns totally closed or with a side openingless than 50 per cent of the wall height. The milking parlour was designed with two or more turns more than 90° (9.3 per cent), and failed to allow cows to see the parlour before entering (45.2 per cent). On 52.0 per cent of dairies, more than 15 per cent of the cows had to be forcefully moved into the milking parlour. In conclusion, there was a big variation in the animal welfare levels within and across farms and they could benefit from others by changing management practices related to facilities and herds. PMID:29018530

[Teaching pediatrics to residents via conventional lectures in France: A national survey from students].

PubMed

Girard, B; Bendavid, M; Faivre, J-C; Salleron, J; Debillon, T; Claris, O; Chabrol, B; Schweitzer, C; Gajdos, V

2017-08-01

To assess the point of view of young physicians training in pediatrics in France on their theoretical courses during residency. A free-access electronic anonymous survey was sent three times by e-mail to the 1215 residents in pediatrics, from July to October 2015. Fifty-seven percent of French residents in pediatrics responded to the survey. It was established that they took part in six (range, 3-10) half-days of specific theoretical teaching in pediatrics from November 2014 to mid-April 2015. Only 54% participated in more than 75% of regional theoretical training. The main self-declared reason for their absence was that they could not leave their clinical activities. Fifty-three per cent of the residents took part in additional training, 45% of them because they found the primary theoretical training insufficient. The overall quality of the theoretical teaching was rated 5 (range, 3-7) out of 10. Eighty-five percent of residents expected to be evaluated on their knowledge during their residency. In pediatrics, additional training is individually undertaken because they deemed their initial training insufficient during their residency. An evaluation of knowledge is requested by residents. The reform of the national residency program must take into account these results in redesigning the theoretical training in pediatrics, integrating innovative teaching techniques to daily practice, for example. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Health literacy on tuberculosis amongst vulnerable segment of population: special reference to Saharia tribe in central India.

PubMed

Muniyandi, M; Rao, V G; Bhat, J; Yadav, R; Sharma, R K; Bhondeley, M K

2015-05-01

Health literacy on tuberculosis (TB) is an understanding about TB to perform activities with regard to prevention, diagnosis and treatment. We undertook a study to assess the health literacy on TB among one of the vulnerable tribal groups (Saharia) in central India. In this cross-sectional study, 2721 individuals aged >15 yr from two districts of Madhya Pradesh State of India were interviewed at their residence during December 2012-July 2013. By using a short-form questionnaire, health literacy on cause, symptoms, mode of transmission, diagnosis, treatment and prevention of TB was assessed. Of the 2721 (Gwalior 1381; Shivpuri 1340) individuals interviewed; 76 per cent were aged <45 yr. Living condition was very poor (62% living in huts/katcha houses, 84 per cent with single room, 89 per cent no separate kitchen, 97 per cent used wood/crop as a fuel). Overall literacy rate was 19 per cent, and 22 per cent had >7 members in a house. Of the 2721 respondents participated, 52 per cent had never heard of TB; among them 8 per cent mentioned cough as a symptom, 64 per cent mentioned coughing up blood, and 91 per cent knew that TB diagnosis, and treatment facilities were available in both government and private hospitals. Health literacy score among participants who had heard of TB was <40 per cent among 36 per cent of respondents, 41-60 per cent among 54 per cent and >60 per cent among 8 per cent of respondents. The finding that nearly half of the respondents had not heard of TB indicated an important gap in education regarding TB in this vulnerable population. There is an urgent need to implement targeted interventions to educate this group for better TB control.

A cross-sectional survey of optometrists and optometric practices in Ghana.

PubMed

Boadi-Kusi, Samuel Bert; Ntodie, Michael; Mashige, Khathutshelo Percy; Owusu-Ansah, Andrew; Antwi Osei, Kwaku

2015-09-01

The study was conducted to profile optometrists and optometric practices in Ghana. An online survey was conducted among 146 optometrists, who were registered with the Ghana Optometric Association (GOA). It included questions on their demographics, equipment, ophthalmic procedures routinely conducted and the barriers to providing a full scope of optometric services. Ninety registered optometrists (62 per cent) responded, their mean age being 28.97 ± 3.36 years. There were more males (68.9 per cent) than females and most had the Doctor of Optometry (OD) degree, the profession's highest degree in Ghana. There were more practitioners in urban centres (71.1 per cent) and most practices had basic optometric instruments, such as direct ophthalmoscopes, slitlamp biomicroscopes and retinoscopes. Many optometrists routinely conducted direct ophthalmoscopy (100 per cent), slitlamp biomicroscopy (87.5 per cent) and contact tonometry (55.7 per cent); however, few provided contact lens (10.2 per cent) and low vision (9.1 per cent) assessments, with 76 per cent stating that it was due to the unavailability of low vision devices, poor sources of contact lenses (27 per cent) and perceived insufficient training (11.2 per cent). Many practitioners (97 per cent) reported the use of diagnostic pharmaceutical agents and therapeutic pharmaceutical agents (96.6 per cent). Most practitioners (52.9 per cent) preferred conferences for the delivery of continuous professional development over publications (26.4 per cent) and internet resources (12.6 per cent). The data elicited in this study provide a basis for addressing the country's unmet eye-care needs and can be used to determine training and support guidelines for the profession. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

[Perception of common symptomatology during pregnancy, puerperium and lactation].

PubMed

Salinas Martínez, A M; Martínez Sánchez, C; Pérez Segura, J

1991-01-01

The objective of this investigation was to identify women's perception on normal and abnormal symptoms of pregnancy, puerperium and breastfeeding; its purpose was to assess the varying educational needs in the geographical area where a reproductive health education program will be implemented. 405 fertile females living in non-residential areas were interviewed in their homes. A predominantly pre-coded questionnaire was used; items related to reproductive health, preventable and susceptible to education were included. Symptomatology perceived incorrectly as normal: a) In pregnancy: Dysuria: 24 percent, genital hemorrhage: 15 per cent, absence of fetal movement: 23 per cent, did not know how to recognize preterm birth symptoms: 70 per cent. b) In puerperium: Increased quantity in lochia rubra: 17 per cent, fever: 22 per cent, fetid lochia: 28 per cent, and c) In breastfeeding: Breasts red and warm: 48 per cent, fever: 30 per cent, nipple fissures: 70 per cent. Symptomatology perceived incorrectly as abnormal: a) In pregnancy: Frequent urination: 17 per cent, morning nausea in the 1st trimester: 9 per cent, emotional instability: 21 per cent, Braxton Hicks contractions: 41 per cent, and b) Postpartum period: Decreased quantity in lochia rubra: 9 per cent, non-fetid lochia alba: 43 per cent, calostrum: 20 per cent. The assessment educational needs showed an inaccurate identification of abnormal and normal obstetric events; its frequency varied. It is essential that a pregnant woman be well informed and educated in order to preserve her own health as well as that of her unborn child. She must be able to recognize warning signs, take action and demand appropriate medical care. Health care personnel and health educators must be responsible for the promoting of maternal and child health during pregnancy.

The detectability of brown dwarfs - Predictions and uncertainties

NASA Technical Reports Server (NTRS)

Nelson, L. A.; Rappaport, S.; Joss, P. C.

1993-01-01

In order to determine the likelihood for the detection of isolated brown dwarfs in ground-based observations as well as in future spaced-based astronomy missions, and in order to evaluate the significance of any detections that might be made, we must first know the expected surface density of brown dwarfs on the celestial sphere as a function of limiting magnitude, wavelength band, and Galactic latitude. It is the purpose of this paper to provide theoretical estimates of this surface density, as well as the range of uncertainty in these estimates resulting from various theoretical uncertainties. We first present theoretical cooling curves for low-mass stars that we have computed with the latest version of our stellar evolution code. We use our evolutionary results to compute theoretical brown-dwarf luminosity functions for a wide range of assumed initial mass functions and stellar birth rate functions. The luminosity functions, in turn, are utilized to compute theoretical surface density functions for brown dwarfs on the celestial sphere. We find, in particular, that for reasonable theoretical assumptions, the currently available upper bounds on the brown-dwarf surface density are consistent with the possibility that brown dwarfs contribute a substantial fraction of the mass of the Galactic disk.

The retention of pit and fissure sealants placed in primary school children by Dental Health Services, Victoria.

PubMed

Messer, L B; Calache, H; Morgan, M V

1997-08-01

The benefit of a public sector sealant programme for children in Australia is yet to be established. This study evaluated sealants placed by therapists of the School Dental Service in Victoria, between 1989 and 1994, on permanent teeth of children in 15 primary schools in Melbourne. Seven hundred and seventy four children aged 6-12 years were examined in school dental clinics by six calibrated examiners. A total of 5363 sealants placed on 2875 permanent teeth (including 2616 first molars, 91 per cent of sample) up to four and a half years previously was examined. Values for complete and partial sealant retention were highest for premolars (86 per cent, 9 per cent respectively, total 95 per cent); similar for occlusal surfaces of maxillary and mandibular first molars (63 per cent, 30 per cent; 62 per cent, 32 per cent respectively) and buccal pits of mandibular molars (66 per cent); and low for pits/fissures of Carabelli's cusps of maxillary molars (44 per cent). Cross-sectional examination up to 24 months for both maxillary and mandibular first molars indicated average values of 67 per cent complete retention, 27 per cent partial retention, 6 per cent missing; thereafter complete retention decreased and partial retention increased. Sealant failures in the six months post-placement were attributed to technique failure. Regardless of sealant retention, caries experience was low under partially retained or missing sealants (4.5 per cent) and completely retained sealants (0.4 per cent). It is concluded that the SDS sealant programme is a sound preventive dental public health approach.

Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before–after control-impact study

PubMed Central

Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle

2013-01-01

Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before–after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod. PMID:23303544

A higher-than-predicted measurement of iron opacity at solar interior temperatures.

PubMed

Bailey, J E; Nagayama, T; Loisel, G P; Rochau, G A; Blancard, C; Colgan, J; Cosse, Ph; Faussurier, G; Fontes, C J; Gilleron, F; Golovkin, I; Hansen, S B; Iglesias, C A; Kilcrease, D P; MacFarlane, J J; Mancini, R C; Nahar, S N; Orban, C; Pain, J-C; Pradhan, A K; Sherrill, M; Wilson, B G

2015-01-01

Nearly a century ago it was recognized that radiation absorption by stellar matter controls the internal temperature profiles within stars. Laboratory opacity measurements, however, have never been performed at stellar interior conditions, introducing uncertainties in stellar models. A particular problem arose when refined photosphere spectral analysis led to reductions of 30-50 per cent in the inferred amounts of carbon, nitrogen and oxygen in the Sun. Standard solar models using the revised element abundances disagree with helioseismic observations that determine the internal solar structure using acoustic oscillations. This could be resolved if the true mean opacity for the solar interior matter were roughly 15 per cent higher than predicted, because increased opacity compensates for the decreased element abundances. Iron accounts for a quarter of the total opacity at the solar radiation/convection zone boundary. Here we report measurements of wavelength-resolved iron opacity at electron temperatures of 1.9-2.3 million kelvin and electron densities of (0.7-4.0) × 10(22) per cubic centimetre, conditions very similar to those in the solar region that affects the discrepancy the most: the radiation/convection zone boundary. The measured wavelength-dependent opacity is 30-400 per cent higher than predicted. This represents roughly half the change in the mean opacity needed to resolve the solar discrepancy, even though iron is only one of many elements that contribute to opacity.

Selection biases in empirical p(z) methods for weak lensing

DOE PAGES

Gruen, D.; Brimioulle, F.

2017-02-23

To measure the mass of foreground objects with weak gravitational lensing, one needs to estimate the redshift distribution of lensed background sources. This is commonly done in an empirical fashion, i.e. with a reference sample of galaxies of known spectroscopic redshift, matched to the source population. In this paper, we develop a simple decision tree framework that, under the ideal conditions of a large, purely magnitude-limited reference sample, allows an unbiased recovery of the source redshift probability density function p(z), as a function of magnitude and colour. We use this framework to quantify biases in empirically estimated p(z) caused bymore » selection effects present in realistic reference and weak lensing source catalogues, namely (1) complex selection of reference objects by the targeting strategy and success rate of existing spectroscopic surveys and (2) selection of background sources by the success of object detection and shape measurement at low signal to noise. For intermediate-to-high redshift clusters, and for depths and filter combinations appropriate for ongoing lensing surveys, we find that (1) spectroscopic selection can cause biases above the 10 per cent level, which can be reduced to ≈5 per cent by optimal lensing weighting, while (2) selection effects in the shape catalogue bias mass estimates at or below the 2 per cent level. Finally, this illustrates the importance of completeness of the reference catalogues for empirical redshift estimation.« less

External rhinoplasty: a critical analysis of 500 cases.

PubMed

Foda, Hossam M T

2003-06-01

The study presents a comprehensive statistical analysis of a series of 500 consecutive rhinoplasties of which 380 (76 per cent) were primary and 120 (24 per cent) were secondary cases. All cases were operated upon using the external rhinoplasty technique; simultaneous septal surgery was performed in 350 (70 per cent) of the cases. Deformities of the upper two-thirds of the nose that occurred significantly more in the secondary cases included; dorsal saddling, dorsal irregularities, valve collapse, open roof and pollybeak deformities. In the lower third of the nose; secondary cases showed significantly higher incidences of depressed tip, tip over-rotation, tip asymmetry, retracted columella, and alar notching. Suturing techniques were used significantly more in primary cases, while in secondary cases grafting techniques were used significantly more. The complications encountered intra-operatively included; septal flap tears (2.8 per cent) and alar cartilage injury (1.8 per cent), while post-operative complications included; nasal trauma (one per cent), epistaxis (two per cent), infection (2.4 per cent), prolonged oedema (17 per cent), and nasal obstruction (0.8 per cent). The overall patient satisfaction rate was 95.6 per cent and the transcolumellar scar was found to be unacceptable in only 0.8 per cent of the patients.

Galaxy And Mass Assembly: automatic morphological classification of galaxies using statistical learning

NASA Astrophysics Data System (ADS)

Sreejith, Sreevarsha; Pereverzyev, Sergiy, Jr.; Kelvin, Lee S.; Marleau, Francine R.; Haltmeier, Markus; Ebner, Judith; Bland-Hawthorn, Joss; Driver, Simon P.; Graham, Alister W.; Holwerda, Benne W.; Hopkins, Andrew M.; Liske, Jochen; Loveday, Jon; Moffett, Amanda J.; Pimbblet, Kevin A.; Taylor, Edward N.; Wang, Lingyu; Wright, Angus H.

2018-03-01

We apply four statistical learning methods to a sample of 7941 galaxies (z < 0.06) from the Galaxy And Mass Assembly survey to test the feasibility of using automated algorithms to classify galaxies. Using 10 features measured for each galaxy (sizes, colours, shape parameters, and stellar mass), we apply the techniques of Support Vector Machines, Classification Trees, Classification Trees with Random Forest (CTRF) and Neural Networks, and returning True Prediction Ratios (TPRs) of 75.8 per cent, 69.0 per cent, 76.2 per cent, and 76.0 per cent, respectively. Those occasions whereby all four algorithms agree with each other yet disagree with the visual classification (`unanimous disagreement') serves as a potential indicator of human error in classification, occurring in ˜ 9 per cent of ellipticals, ˜ 9 per cent of little blue spheroids, ˜ 14 per cent of early-type spirals, ˜ 21 per cent of intermediate-type spirals, and ˜ 4 per cent of late-type spirals and irregulars. We observe that the choice of parameters rather than that of algorithms is more crucial in determining classification accuracy. Due to its simplicity in formulation and implementation, we recommend the CTRF algorithm for classifying future galaxy data sets. Adopting the CTRF algorithm, the TPRs of the five galaxy types are : E, 70.1 per cent; LBS, 75.6 per cent; S0-Sa, 63.6 per cent; Sab-Scd, 56.4 per cent, and Sd-Irr, 88.9 per cent. Further, we train a binary classifier using this CTRF algorithm that divides galaxies into spheroid-dominated (E, LBS, and S0-Sa) and disc-dominated (Sab-Scd and Sd-Irr), achieving an overall accuracy of 89.8 per cent. This translates into an accuracy of 84.9 per cent for spheroid-dominated systems and 92.5 per cent for disc-dominated systems.

Skin injuries identified in cattle and water buffaloes at livestock markets in Bangladesh.

PubMed

Alam, M R; Gregory, N G; Jabbar, M A; Uddin, M S; Kibria, A S M G; Silva-Fletcher, A

2010-09-11

Skin injuries were assessed in 560 imported and local cattle and water buffaloes at two livestock markets in Bangladesh. The body of each animal was divided into 11 anatomical regions, and abrasions, lacerations, penetrations, ulcerations, bleeding, swelling, hyperkeratosis and scars were recorded for each region. Among the 560 animals studied, 501 were found to have at least one injury. The prevalence of skin injuries was 89 per cent, with 84 per cent of the cattle and 99 per cent of the water buffaloes having obvious skin injuries. The most common types of injury were abrasions that were found in 73 per cent of the animals, followed by scars (50 per cent), and lacerations (41 per cent). Buffaloes had more abrasions (95 per cent), lacerations (57 per cent), swelling (15 per cent) and hyperkeratosis (32 per cent) compared with cattle, whereas scars (60 per cent) were more common in cattle (P<0.001). Within the 11 different anatomical regions, all types of injuries were present but in different proportions. The buttock region had a higher proportion of abrasions (36 per cent) followed by the hip, hindlimb and back regions. Penetration, ulceration, bleeding and swelling were present at lower frequencies in all regions. Causes for these injuries included rubbing against the inside wall of vehicles used for transportation and stock-handler abuse (59 per cent and 13 per cent, respectively). Buffaloes sustained more transport injuries than cattle, and the number of injuries was higher in imported than local animals.

Comparison of indium-labeled-leukocyte imaging with sequential technetium-gallium scanning in the diagnosis of low-grade musculoskeletal sepsis. A prospective study

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

Merkel, K.D.; Brown, M.L.; Dewanjee, M.K.

We prospectively compared sequential technetium-gallium imaging with indium-labeled-leukocyte imaging in fifty patients with suspected low-grade musculoskeletal sepsis. Adequate images and follow-up examinations were obtained for forty-two patients. The presence or absence of low-grade sepsis was confirmed by histological and bacteriological examinations of tissue specimens taken at surgery in thirty of the forty-two patients. In these thirty patients, the sensitivity of sequential Tc-Ga imaging was 48 per cent, the specificity was 86 per cent, and the accuracy was 57 per cent, whereas the sensitivity of the indium-labeled-leukocyte technique was 83 per cent, the specificity was 86 per cent, and the accuracymore » was 83 per cent. When the additional twelve patients for whom surgery was deemed unnecessary were considered, the sensitivity of sequential Tc-Ga imaging was 50 per cent, the specificity was 78 per cent, and the accuracy was 62 per cent, as compared with a sensitivity of 83 per cent, a specificity of 94 per cent, and an accuracy of 88 per cent with the indium-labeled-leukocyte method. In patients with a prosthesis the indium-labeled-leukocyte image was 94 per cent accurate, compared with 75 per cent accuracy for sequential Tc-Ga imaging. Statistical analysis of these data demonstrated that the indium-labeled-leukocyte technique was superior to sequential Tc-Ga imaging in detecting areas of low-grade musculoskeletal sepsis.« less

Identification and characterization of functional centromeres of the common bean.

PubMed

Iwata, Aiko; Tek, Ahmet L; Richard, Manon M S; Abernathy, Brian; Fonsêca, Artur; Schmutz, Jeremy; Chen, Nicolas W G; Thareau, Vincent; Magdelenat, Ghislaine; Li, Yupeng; Murata, Minoru; Pedrosa-Harand, Andrea; Geffroy, Valérie; Nagaki, Kiyotaka; Jackson, Scott A

2013-10-01

In higher eukaryotes, centromeres are typically composed of megabase-sized arrays of satellite repeats that evolve rapidly and homogenize within a species' genome. Despite the importance of centromeres, our knowledge is limited to a few model species. We conducted a comprehensive analysis of common bean (Phaseolus vulgaris) centromeric satellite DNA using genomic data, fluorescence in situ hybridization (FISH), immunofluorescence and chromatin immunoprecipitation (ChIP). Two unrelated centromere-specific satellite repeats, CentPv1 and CentPv2, and the common bean centromere-specific histone H3 (PvCENH3) were identified. FISH showed that CentPv1 and CentPv2 are predominantly located at subsets of eight and three centromeres, respectively. Immunofluorescence- and ChIP-based assays demonstrated the functional significance of CentPv1 and CentPv2 at centromeres. Genomic analysis revealed several interesting features of CentPv1 and CentPv2: (i) CentPv1 is organized into an higher-order repeat structure, named Nazca, of 528 bp, whereas CentPv2 is composed of tandemly organized monomers; (ii) CentPv1 and CentPv2 have undergone chromosome-specific homogenization; and (iii) CentPv1 and CentPv2 are not likely to be commingled in the genome. These findings suggest that two distinct sets of centromere sequences have evolved independently within the common bean genome, and provide insight into centromere satellite evolution. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

A study of tail tip necrosis in young fattening bulls on slatted floors.

PubMed

Madsen, E B; Nielsen, K

1985-01-01

A questionnaire sent to 78 producers revealed that tail tip necrosis was seen only in units with fattening bulls housed on slatted floors. Out of 43 such units, 20 (46.5 per cent) reported that tail tip necrosis was a herd problem. All 43 herds were visited, owners were interviewed and housing and management data recorded. It is concluded that tail tip necrosis is a multifactorial disease. The initial lesion is caused by tramping, but the following factors are essential in the development and severity of the disease, i) slatted concrete floors, ii) close confinement, iii) hot season and iv) body weight above 200 kg. The stocking density (expressed as kg bodyweight per square meter pen) was significantly higher in problem herds (210 kg/m2) than in control herds (165 kg/m2). There was a close relationship between high environmental temperature and tail tip necroses. The majority of incidents occurred during the warm season (May through September), very few cases were seen during the colder months. The general morbidity and mortality rates were significantly higher in problem herds than in control herds. Microbiology of affected tails revealed mixed infections in most cases, with Corynebacterium pyogenes and Bacteroides melaninogenicus as the most frequently isolated organisms. Principles of treatment and prevention are discussed. There is evidence to assume that a 10-20 per cent reduction in stocking density could be an efficient prophylactic measure.

redMaGiC: Selecting luminous red galaxies from the DES Science Verification data

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

Rozo, E.; Rykoff, E. S.; Abate, A.

Here, we introduce redMaGiC, an automated algorithm for selecting luminous red galaxies (LRGs). The algorithm was specifically developed to minimize photometric redshift uncertainties in photometric large-scale structure studies. redMaGiC achieves this by self-training the colour cuts necessary to produce a luminosity-thresholded LRG sample of constant comoving density. We demonstrate that redMaGiC photo-zs are very nearly as accurate as the best machine learning-based methods, yet they require minimal spectroscopic training, do not suffer from extrapolation biases, and are very nearly Gaussian. We apply our algorithm to Dark Energy Survey (DES) Science Verification (SV) data to produce a redMaGiC catalogue sampling themore » redshift range z ϵ [0.2, 0.8]. Our fiducial sample has a comoving space density of 10 –3 (h –1 Mpc) –3, and a median photo-z bias (zspec – zphoto) and scatter (σz/(1 + z)) of 0.005 and 0.017, respectively. The corresponding 5σ outlier fraction is 1.4 per cent. We also test our algorithm with Sloan Digital Sky Survey Data Release 8 and Stripe 82 data, and discuss how spectroscopic training can be used to control photo-z biases at the 0.1 per cent level.« less

redMaGiC: Selecting luminous red galaxies from the DES Science Verification data

DOE PAGES

Rozo, E.; Rykoff, E. S.; Abate, A.; ...

2016-05-30

Here, we introduce redMaGiC, an automated algorithm for selecting luminous red galaxies (LRGs). The algorithm was specifically developed to minimize photometric redshift uncertainties in photometric large-scale structure studies. redMaGiC achieves this by self-training the colour cuts necessary to produce a luminosity-thresholded LRG sample of constant comoving density. We demonstrate that redMaGiC photo-zs are very nearly as accurate as the best machine learning-based methods, yet they require minimal spectroscopic training, do not suffer from extrapolation biases, and are very nearly Gaussian. We apply our algorithm to Dark Energy Survey (DES) Science Verification (SV) data to produce a redMaGiC catalogue sampling themore » redshift range z ϵ [0.2, 0.8]. Our fiducial sample has a comoving space density of 10 –3 (h –1 Mpc) –3, and a median photo-z bias (zspec – zphoto) and scatter (σz/(1 + z)) of 0.005 and 0.017, respectively. The corresponding 5σ outlier fraction is 1.4 per cent. We also test our algorithm with Sloan Digital Sky Survey Data Release 8 and Stripe 82 data, and discuss how spectroscopic training can be used to control photo-z biases at the 0.1 per cent level.« less

Body mass index and overweight in relation to residence distance and population density: experience from the Northern Finland birth cohort 1966.

PubMed

Näyhä, Simo; Lankila, Tiina; Rautio, Arja; Koiranen, Markku; Tammelin, Tuija H; Taanila, Anja; Rusanen, Jarmo; Laitinen, Jaana

2013-10-08

The effect of urban sprawl on body weight in Finland is not well known. To provide more information, we examined whether body mass index (BMI) and the prevalence of overweight are associated with an individual's distance to the local community centre and population density in his/her resident area. The sample consisted of 5363 men and women, members of the Northern Finland Birth Cohort 1966 (NFBC), who filled in a postal questionnaire and attended a medical checkup in 1997, at the age of 31 years. Body mass index (BMI; kg/m(2)) and the prevalence of overweight (BMI ≥ 25.0 kg/m(2)) were regressed on each subject's road distance to the resident commune's centre and on population density in the 1 km(2) geographical grid in which he/she resided, using a generalized additive model. Adjustments were made for sex, marital status, occupational class, education, leisure-time and occupational physical activity, alcohol consumption and smoking. The mean BMI among the subjects was 24.7 kg/m(2), but it increased by increasing road distance (by 1.3 kg/m(2) from 5-10 to 20-184 km) and by decreasing population density (by 1.7 kg/m(2) from 1000-19,192 to 1-5 inhabitants/km(2)). The respective increases in overweight (overall prevalence 41%) were 13 per cent units for distance and 14 per cent units for population density. Adjusted regressions based on continuous explanatory variables showed an inverse L-shaped pattern with a mean BMI of 24.6 kg/m(2) at distances shorter than 5 km and a rise of 2.6 kg/m(2) at longer distances, and an increase of 2.5 kg/m(2) from highest to lowest population density. The associations with road distance were stronger for women than men, while the sex difference in association with population density remained indeterminate. We conclude that young adults in Northern Finland who live far away from local centres or in the most sparsely populated areas are fatter than those who live close to local centres or in densely populated areas. The likely explanations include variations in everyday physical activity in different residential environments, although causality of the associations remains to be confirmed.

Body mass index and overweight in relation to residence distance and population density: experience from the Northern Finland birth cohort 1966

PubMed Central

2013-01-01

Background The effect of urban sprawl on body weight in Finland is not well known. To provide more information, we examined whether body mass index (BMI) and the prevalence of overweight are associated with an individual’s distance to the local community centre and population density in his/her resident area. Methods The sample consisted of 5363 men and women, members of the Northern Finland Birth Cohort 1966 (NFBC), who filled in a postal questionnaire and attended a medical checkup in 1997, at the age of 31 years. Body mass index (BMI; kg/m2) and the prevalence of overweight (BMI ≥ 25.0 kg/m2) were regressed on each subject’s road distance to the resident commune’s centre and on population density in the 1 km2 geographical grid in which he/she resided, using a generalized additive model. Adjustments were made for sex, marital status, occupational class, education, leisure-time and occupational physical activity, alcohol consumption and smoking. Results The mean BMI among the subjects was 24.7 kg/m2, but it increased by increasing road distance (by 1.3 kg/m2 from 5–10 to 20–184 km) and by decreasing population density (by 1.7 kg/m2 from 1000–19,192 to 1–5 inhabitants/km2). The respective increases in overweight (overall prevalence 41%) were 13 per cent units for distance and 14 per cent units for population density. Adjusted regressions based on continuous explanatory variables showed an inverse L-shaped pattern with a mean BMI of 24.6 kg/m2 at distances shorter than 5 km and a rise of 2.6 kg/m2 at longer distances, and an increase of 2.5 kg/m2 from highest to lowest population density. The associations with road distance were stronger for women than men, while the sex difference in association with population density remained indeterminate. Conclusions We conclude that young adults in Northern Finland who live far away from local centres or in the most sparsely populated areas are fatter than those who live close to local centres or in densely populated areas. The likely explanations include variations in everyday physical activity in different residential environments, although causality of the associations remains to be confirmed. PMID:24103455

Computation of mass-density images from x-ray refraction-angle images.

PubMed

Wernick, Miles N; Yang, Yongyi; Mondal, Indrasis; Chapman, Dean; Hasnah, Moumen; Parham, Christopher; Pisano, Etta; Zhong, Zhong

2006-04-07

In this paper, we investigate the possibility of computing quantitatively accurate images of mass density variations in soft tissue. This is a challenging task, because density variations in soft tissue, such as the breast, can be very subtle. Beginning from an image of refraction angle created by either diffraction-enhanced imaging (DEI) or multiple-image radiography (MIR), we estimate the mass-density image using a constrained least squares (CLS) method. The CLS algorithm yields accurate density estimates while effectively suppressing noise. Our method improves on an analytical method proposed by Hasnah et al (2005 Med. Phys. 32 549-52), which can produce significant artefacts when even a modest level of noise is present. We present a quantitative evaluation study to determine the accuracy with which mass density can be determined in the presence of noise. Based on computer simulations, we find that the mass-density estimation error can be as low as a few per cent for typical density variations found in the breast. Example images computed from less-noisy real data are also shown to illustrate the feasibility of the technique. We anticipate that density imaging may have application in assessment of water content of cartilage resulting from osteoarthritis, in evaluation of bone density, and in mammographic interpretation.

Tree stands, not guns, are the midwestern hunter's most dangerous weapon.

PubMed

Crockett, Andrew; Stawicki, Stanislaw P; Thomas, Yalaunda M; Jarvis, Amy M; Wang, Cecily F; Beery, Paul R; Whitmill, Melissa L; Lindsey, David E; Steinberg, Steven M; Cook, Charles H

2010-09-01

Although the prevailing stereotype is that most hunting injuries are gunshot wounds inflicted by intoxicated hunting buddies, our experience led us to hypothesize that falls comprise a significant proportion of hunting related injuries. Trauma databases of two Level I trauma centers in central Ohio were queried for all hunting related injuries during a 10-year period. One hundred and thirty patients were identified (90% male, mean age 41.0 years, range 17-76). Fifty per cent of injuries resulted from falls, whereas gunshot wounds accounted for 29 per cent. Most hunters were hunting deer and 92 per cent of falls were from tree stands. Alcohol was involved in only 2.3 per cent, and drugs of abuse in 4.6 per cent. Of gunshots, 58 per cent were self-inflicted, and 42 per cent were shot by another hunter. Tree stand falls were highly morbid, with 59 per cent of fall victims suffering spinal fractures, 47 per cent lower extremity fractures, 18 per cent upper extremity fractures, and 18 per cent closed head injuries. Surgery was required for 81 per cent of fall-related injuries, and 8.2 per cent of fall victims had permanent neurological deficits. In contrast to prevailing beliefs, in our geographic area tree-stand falls are the most common mechanism of hunting related injury requiring admission to a Level 1 trauma center.

Incomplete antibodies and immunoglobulin characterization in adult urodeles, Pleurodeles waltlii Michah. and Triturus alpestris Laur.

PubMed Central

Tournefier, A

1975-01-01

Humoral immunoglobulin synthesis has been studied in two adult urodeles, Pleurodeles waltlii Michah. and Triturus alpestris Laur. following SRBC immunization. The specific antibody response is detected after a long period of immunization and is due exclusively to 'incomplete' antibodies which are unable to induce agglutination. The antibody titre is essentially dependent on the number of stimulations rather than on the dose or nature of the antigen (papainized or normal erythrocytes). Antibodies are detected in only 50 per cent of the immunized animals, 50 per cent never respond. This suggests that the latter group does not possess the genetic equipment (Ir genes) to recognize the antigenic determinants and to synthesize the corresponding antibodies. The sedimentation coefficient of the synthesized immunoglobulins was investigated by sucrose density gradient centrifugation and their characterization was carried out by starch and polyacrylamide gel electrophoresis. With this peculiar antigen even after a booster injection, only one class of immunoglobulin, an 18-2S IgM could be detected. PMID:49296

Lyman continuum leaking AGN in the SSA22 field

NASA Astrophysics Data System (ADS)

Micheva, Genoveva; Iwata, Ikuru; Inoue, Akio K.

2017-02-01

Subaru/SuprimeCam narrow-band photometry of the SSA22 field reveals the presence of four Lyman continuum (LyC) candidates among a sample of 14 active galactic nuclei (AGNs). Two show offsets and likely have stellar LyCin nature or are foreground contaminants. The remaining two LyC candidates are type I AGN. We argue that the average LyC escape fraction of high-redshift, low-luminosity AGN is not likely to be unity, as often assumed in the literature. From direct measurement we obtain the average LyC-to-UV flux density ratio and ionizing emissivity for a number of AGN classes and find it at least a factor of 2 lower than values obtained assuming fesc = 1. Comparing to recent Ly α forest measurements, AGNs at redshift z ˜ 3 make up at most ˜12 per cent and as little as ˜5 per cent of the total ionizing budget. Our results suggest that AGNs are unlikely to dominate the ionization budget of the Universe at high redshifts.

Galaxy And Mass Assembly: resolving the role of environment in galaxy evolution

NASA Astrophysics Data System (ADS)

Brough, S.; Croom, S.; Sharp, R.; Hopkins, A. M.; Taylor, E. N.; Baldry, I. K.; Gunawardhana, M. L. P.; Liske, J.; Norberg, P.; Robotham, A. S. G.; Bauer, A. E.; Bland-Hawthorn, J.; Colless, M.; Foster, C.; Kelvin, L. S.; Lara-Lopez, M. A.; López-Sánchez, Á. R.; Loveday, J.; Owers, M.; Pimbblet, K. A.; Prescott, M.

2013-11-01

We present observations of 18 galaxies from the Galaxy And Mass Assembly (GAMA) survey made with the SPIRAL optical integral field unit (IFU) on the Anglo-Australian Telescope. The galaxies are selected to have a narrow range in stellar mass (6 × 109 < M* < 2 × 1010 M⊙) in order to focus on the effects of environment. Local galaxy environments are measured quantitatively using fifth nearest neighbour surface densities. We find that the total star formation rates (SFR) measured from the IFU data are consistent with total SFRs measured from aperture correcting either GAMA or Sloan Digital Sky Survey single-fibre observations. The mean differences are SFRGAMA/SFRIFU = 1.26 ± 0.23, σ = 0.90 and for the Sloan Digital Sky Survey we similarly find SFRBrinchmann/SFRIFU = 1.34 ± 0.17, σ = 0.67. Examining the relationships with environment, we find that off-centre and clumpy Hα emission is not significantly dependent on environment, being present in 2/7 (29^{+20}_{-11} per cent) galaxies in high-density environments (>0.77 Mpc-2), and 5/11 (45^{+15}_{-13} per cent) galaxies in low-density environments (<0.77 Mpc-2). We find a weak but not significant relationship of the total SFRs of star-forming galaxies with environment. Due to the size of our sample and the scatter observed we do not draw a definitive conclusion about a possible SFR dependence on environment. Examining the spatial distribution of the Hα emission, we find no evidence for a change in shape or amplitude of the radial profile of star-forming galaxies with environment. If these observations are borne out in larger samples, this would infer that any environment-driven star formation suppression must either act very rapidly (the `infall-and-quench' model) or that galaxies must evolve in a density-dependent manner (an `in situ evolution' model).

Health literacy on tuberculosis amongst vulnerable segment of population: special reference to Saharia tribe in central India

PubMed Central

Muniyandi, M.; Rao, V.G.; Bhat, J.; Yadav, R.; Sharma, R.K.; Bhondeley, M.K.

2015-01-01

Background & objectives: Health literacy on tuberculosis (TB) is an understanding about TB to perform activities with regard to prevention, diagnosis and treatment. We undertook a study to assess the health literacy on TB among one of the vulnerable tribal groups (Saharia) in central India. Methods: In this cross-sectional study, 2721 individuals aged >15 yr from two districts of Madhya Pradesh State of India were interviewed at their residence during December 2012-July 2013. By using a short-form questionnaire, health literacy on cause, symptoms, mode of transmission, diagnosis, treatment and prevention of TB was assessed. Results: Of the 2721 (Gwalior 1381; Shivpuri 1340) individuals interviewed; 76 per cent were aged <45 yr. Living condition was very poor (62% living in huts/katcha houses, 84 per cent with single room, 89 per cent no separate kitchen, 97 per cent used wood/crop as a fuel). Overall literacy rate was 19 per cent, and 22 per cent had >7 members in a house. Of the 2721 respondents participated, 52 per cent had never heard of TB; among them 8 per cent mentioned cough as a symptom, 64 per cent mentioned coughing up blood, and 91 per cent knew that TB diagnosis, and treatment facilities were available in both government and private hospitals. Health literacy score among participants who had heard of TB was <40 per cent among 36 per cent of respondents, 41-60 per cent among 54 per cent and >60 per cent among 8 per cent of respondents. Interpretation & conclusions: The finding that nearly half of the respondents had not heard of TB indicated an important gap in education regarding TB in this vulnerable population. There is an urgent need to implement targeted interventions to educate this group for better TB control. PMID:26139783

Duane's retraction syndrome: a retrospective review from Kathmandu, Nepal.

PubMed

Shrestha, Gauri Shankar; Sharma, Ananda Kumar

2012-01-01

  The aim was to study the clinical characteristics of Duane's retraction syndrome (DRS) in Nepalese patients.   Medical records from 52 cases of DRS from May 2003 to April 2010 were retrospectively reviewed for age, gender, laterality and clinical characteristics. Forty-one case records (78.8 per cent) that had complete clinical findings were considered for further evaluation. Examination included visual acuity by Snellen chart, refraction, associated horizontal and vertical strabismus in primary gaze, upshoot and downshoot on attempted adduction, binocular vision assessed with the Worth four-dot test on adopted gaze and stereopsis examined with the Titmus stereo test.   DRS type I was the most common type observed in 73.2 per cent of cases, followed by DRS type II (14.6 per cent) and DRS type III (12.2 per cent). It was more common in female patients (58.5 per cent) than male patients (χ(2) = 4.6, df = 1, p = 0.03). DRS was more common in the left eye (68.3 per cent) than the right eye and unilaterally present in 95.1 per cent of subjects. In primary gaze, orthotropia (41.5 per cent) was more common than exotropia (34.1 per cent) and esotropia (24.4 per cent) and vertical strabismus was present in 24.4 per cent of subjects. Upshoot and downshoot on attempted adduction was seen in 14.6 and 9.8 per cent, respectively. Binocular single vision was present in 68.3 per cent of subjects by Worth four-dot test at near. Stereopsis of 3,000 seconds of arc was present in 9.8 per cent, 100 to 200 seconds of arc in 14.6 per cent and 40 to 60 seconds of arc in 43.9 per cent with the Titmus stereo test.   DRS is more common in female patients and the left eye. DRS type I is the most common type. © 2011 The Authors. Clinical and Experimental Optometry © 2011 Optometrists Association Australia.

Constraining the Galactic structure parameters with the XSTPS-GAC and SDSS photometric surveys

NASA Astrophysics Data System (ADS)

Chen, B.-Q.; Liu, X.-W.; Yuan, H.-B.; Robin, A. C.; Huang, Y.; Xiang, M.-S.; Wang, C.; Ren, J.-J.; Tian, Z.-J.; Zhang, H.-W.

2017-01-01

Photometric data from the Xuyi Schmidt Telescope Photometric Survey of the Galactic Anticentre (XSTPS-GAC) and the Sloan Digital Sky Survey (SDSS) are used to derive the global structure parameters of the smooth components of the Milky Way. The data, which cover nearly 11 000 deg2 sky area and the full range of Galactic latitude, allow us to construct a globally representative Galactic model. The number density distribution of Galactic halo stars is fitted with an oblate spheroid that decays by power law. The best fitting yields an axis ratio and a power-law index κ = 0.65 and p = 2.79, respectively. The r-band differential star counts of three dwarf samples are then fitted with a Galactic model. The best-fitting model yielded by a Markov Chain Monte Carlo analysis has thin and thick disc scale heights and lengths of H1 = 322 pc and L1 = 2343 pc, H2 = 794 pc and L2 = 3638 pc, a local thick-to-thin disc density ratio of f2 = 11 per cent, and a local density ratio of the oblate halo to the thin disc of fh = 0.16 per cent. The measured star count distribution, which is in good agreement with the above model for most of the sky area, shows a number of statistically significant large-scale overdensities, including some of the previously known substructures, such as the Virgo overdensity and the so-called `north near structure', and a new feature between 150° < l < 240° and -1° < b < -5°, at an estimated distance between 1.0 and 1.5 kpc. The Galactic North-South asymmetry in the anticentre is even stronger than previously thought.

The ATLAS3D Project - XXX. Star formation histories and stellar population scaling relations of early-type galaxies

NASA Astrophysics Data System (ADS)

McDermid, Richard M.; Alatalo, Katherine; Blitz, Leo; Bournaud, Frédéric; Bureau, Martin; Cappellari, Michele; Crocker, Alison F.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnović, Davor; Kuntschner, Harald; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Scott, Nicholas; Serra, Paolo; Weijmans, Anne-Marie; Young, Lisa M.

2015-04-01

We present the stellar population content of early-type galaxies from the ATLAS3D survey. Using spectra integrated within apertures covering up to one effective radius, we apply two methods: one based on measuring line-strength indices and applying single stellar population (SSP) models to derive SSP-equivalent values of stellar age, metallicity, and alpha enhancement; and one based on spectral fitting to derive non-parametric star formation histories, mass-weighted average values of age, metallicity, and half-mass formation time-scales. Using homogeneously derived effective radii and dynamically determined galaxy masses, we present the distribution of stellar population parameters on the Mass Plane (MJAM, σe, R^maj_e), showing that at fixed mass, compact early-type galaxies are on average older, more metal-rich, and more alpha-enhanced than their larger counterparts. From non-parametric star formation histories, we find that the duration of star formation is systematically more extended in lower mass objects. Assuming that our sample represents most of the stellar content of today's local Universe, approximately 50 per cent of all stars formed within the first 2 Gyr following the big bang. Most of these stars reside today in the most massive galaxies (>1010.5 M⊙), which themselves formed 90 per cent of their stars by z ˜ 2. The lower mass objects, in contrast, have formed barely half their stars in this time interval. Stellar population properties are independent of environment over two orders of magnitude in local density, varying only with galaxy mass. In the highest density regions of our volume (dominated by the Virgo cluster), galaxies are older, alpha-enhanced, and have shorter star formation histories with respect to lower density regions.

A polarized fast radio burst at low Galactic latitude

NASA Astrophysics Data System (ADS)

Petroff, E.; Burke-Spolaor, S.; Keane, E. F.; McLaughlin, M. A.; Miller, R.; Andreoni, I.; Bailes, M.; Barr, E. D.; Bernard, S. R.; Bhandari, S.; Bhat, N. D. R.; Burgay, M.; Caleb, M.; Champion, D.; Chandra, P.; Cooke, J.; Dhillon, V. S.; Farnes, J. S.; Hardy, L. K.; Jaroenjittichai, P.; Johnston, S.; Kasliwal, M.; Kramer, M.; Littlefair, S. P.; Macquart, J. P.; Mickaliger, M.; Possenti, A.; Pritchard, T.; Ravi, V.; Rest, A.; Rowlinson, A.; Sawangwit, U.; Stappers, B.; Sullivan, M.; Tiburzi, C.; van Straten, W.; ANTARES Collaboration; Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Ardid, M.; Aubert, J.-J.; Avgitas, T.; Baret, B.; Barrios-Martí, J.; Basa, S.; Bertin, V.; Biagi, S.; Bormuth, R.; Bourret, S.; Bouwhuis, M. C.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Celli, S.; Chiarusi, T.; Circella, M.; Coelho, J. A. B.; Coleiro, A.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Deschamps, A.; de Bonis, G.; Distefano, C.; di Palma, I.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; El Bojaddaini, I.; Elsässer, D.; Enzenhöfer, A.; Felis, I.; Fusco, L. A.; Galatà, S.; Gay, P.; Geißelsöder, S.; Geyer, K.; Giordano, V.; Gleixner, A.; Glotin, H.; Grégoire, T.; Gracia-Ruiz, R.; Graf, K.; Hallmann, S.; van Haren, H.; Heijboer, A. J.; Hello, Y.; Hernández-Rey, J. J.; Hößl, J.; Hofestädt, J.; Hugon, C.; Illuminati, G.; James, C. W.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kießling, D.; Kouchner, A.; Kreter, M.; Kreykenbohm, I.; Kulikovskiy, V.; Lachaud, C.; Lahmann, R.; Lefèvre, D.; Leonora, E.; Lotze, M.; Loucatos, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martínez-Mora, J. A.; Mathieu, A.; Mele, R.; Melis, K.; Michael, T.; Migliozzi, P.; Moussa, A.; Mueller, C.; Nezri, E.; Pǎvǎlaş, G. E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Quinn, L.; Racca, C.; Riccobene, G.; Roensch, K.; Sánchez-Losa, A.; Saldaña, M.; Salvadori, I.; Samtleben, D. F. E.; Sanguineti, M.; Sapienza, P.; Schnabel, J.; Seitz, T.; Sieger, C.; Spurio, M.; Stolarczyk, Th.; Taiuti, M.; Tayalati, Y.; Trovato, A.; Tselengidou, M.; Turpin, D.; Tönnis, C.; Vallage, B.; Vallée, C.; van Elewyck, V.; Vivolo, D.; Vizzoca, A.; Wagner, S.; Wilms, J.; Zornoza, J. D.; Zúñiga, J.; H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Bulik, T.; Capasso, M.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O'c.; Dubus, G.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hadasch, D.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Kerszberg, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morâ, K.; Moulin, E.; Murach, T.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; Reyes, R. De Los; Rieger, F.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schulz, A.; Schüssler, F.; Schwanke, U.; Schwemmer, S.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tuffs, R.; Uchiyama, Y.; Walt, D. J. Van Der; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2017-08-01

We report on the discovery of a new fast radio burst (FRB), FRB 150215, with the Parkes radio telescope on 2015 February 15. The burst was detected in real time with a dispersion measure (DM) of 1105.6 ± 0.8 pc cm-3, a pulse duration of 2.8^{+1.2}_{-0.5} ms, and a measured peak flux density assuming that the burst was at beam centre of 0.7^{+0.2}_{-0.1} Jy. The FRB originated at a Galactic longitude and latitude of 24.66°, 5.28° and 25° away from the Galactic Center. The burst was found to be 43 ± 5 per cent linearly polarized with a rotation measure (RM) in the range -9 < RM < 12 rad m-2 (95 per cent confidence level), consistent with zero. The burst was followed up with 11 telescopes to search for radio, optical, X-ray, γ-ray and neutrino emission. Neither transient nor variable emission was found to be associated with the burst and no repeat pulses have been observed in 17.25 h of observing. The sightline to the burst is close to the Galactic plane and the observed physical properties of FRB 150215 demonstrate the existence of sight lines of anomalously low RM for a given electron column density. The Galactic RM foreground may approach a null value due to magnetic field reversals along the line of sight, a decreased total electron column density from the Milky Way, or some combination of these effects. A lower Galactic DM contribution might explain why this burst was detectable whereas previous searches at low latitude have had lower detection rates than those out of the plane.

Risk factors for vitamin A deficiency in rural areas of the Philippines.

PubMed

Rosen, D S; Sloan, N L; del Rosario, A; de la Paz, T C

1994-04-01

A survey of vitamin A deficiency was conducted in January and February 1991 on the island of Mindanao in the Philippines. Demographic, serum retinol, conjunctival impression cytology (CIC), anthropometric, and dietary data were collected from 248 preschool children in five randomly selected rural communities on the outskirts of Davao City. Twenty-nine per cent [95 per cent confidence interval (CI) 23-35 per cent] of preschool children had serum retinol levels below 20 micrograms/dl. Nearly 6 per cent (95 per cent CI 3-9 per cent) had serum retinol levels below 10 micrograms/dl. Thirty-two per cent (95 per cent CI 25-38 per cent) had abnormal CIC findings. The correlation between serum retinol and CIC results was poor. Recent history of diarrheal disease, reported night blindness, maternal education less than 9 years, and infrequent consumption of eggs, mangoes, and liver were associated with increased risk of vitamin A deficiency.

Comparison of two shampoos as sole treatment for canine bacterial overgrowth syndrome.

PubMed

Viaud, S; Maynard, L; Sanquer, A

2012-06-30

Two antibacterial shampoos for the treatment of canine bacterial overgrowth syndrome (BOGS) were compared in a prospective controlled clinical trial. Forty dogs with clinical signs (pruritus, erythema and excoriations without pustules and/or collarettes) and cytological findings compatible with bacterial overgrowth were treated twice weekly with 3 per cent chlorhexidine shampoo (3 per cent CHX) or 2.5 per cent benzoyl peroxide shampoo (2.5 per cent BPO) and evaluated every two weeks for up to six weeks until cytological cure. Pruritus, erythema, greasy seborrhoea, malodour, excoriations, secondary hair loss, lichenification, hyperpigmentation and lesion extent were each scored on a 0 to 3 severity scale and combined to calculate an aggregate score. Among the 34 dogs with good compliance to treatment, reduction of cocci counts of at least 90 per cent was recorded in 11 of 18 dogs after 3 per cent CHX and nine of 16 dogs after 2.5 per cent BPO, with no significant difference between the two products (P=0.98). Lesion score was significantly reduced in both groups (63.48 (34.45)) per cent with 3 per cent CHX v 54.45 (33.61) per cent with 2.5 per cent BPO, P=0.36) and time to cytological cure was not significantly different between groups (P=0.13), at the end of the treatment. In the present study, 3 per cent CHX and 2.5 per cent BPO were similarly effective in the treatment of canine BOGS.

Efficient waveform tomography for lithospheric imaging: implications for realistic, two-dimensional acquisition geometries and low-frequency data

NASA Astrophysics Data System (ADS)

Brenders, A. J.; Pratt, R. G.

2007-01-01

We provide a series of numerical experiments designed to test waveform tomography under (i) a reduction in the number of input data frequency components (`efficient' waveform tomography), (ii) sparse spatial subsampling of the input data and (iii) an increase in the minimum data frequency used. These results extend the waveform tomography results of a companion paper, using the same third-party, 2-D, wide-angle, synthetic viscoelastic seismic data, computed in a crustal geology model 250 km long and 40 km deep, with heterogeneous P-velocity, S-velocity, density and Q-factor structure. Accurate velocity models were obtained using efficient waveform tomography and only four carefully selected frequency components of the input data: 0.8, 1.7, 3.6 and 7.0 Hz. This strategy avoids the spectral redundancy present in `full' waveform tomography, and yields results that are comparable with those in the companion paper for an 88 per cent decrease in total computational cost. Because we use acoustic waveform tomography, the results further justify the use of the acoustic wave equation in calculating P-wave velocity models from viscoelastic data. The effect of using sparse survey geometries with efficient waveform tomography were investigated for both increased receiver spacing, and increased source spacing. Sampling theory formally requires spatial sampling at maximum interval of one half-wavelength (2.5 km at 0.8 Hz): For data with receivers every 0.9 km (conforming to this criterion), artefacts in the tomographic images were still minimal when the source spacing was as large as 7.6 km (three times the theoretical maximum). Larger source spacings led to an unacceptable degradation of the results. When increasing the starting frequency, image quality was progressively degraded. Acceptable image quality within the central portion of the model was nevertheless achieved using starting frequencies up to 3.0 Hz. At 3.0 Hz the maximum theoretical sample interval is reduced to 0.67 km due to the decreased wavelengths; the available sources were spaced every 5.0 km (more than seven times the theoretical maximum), and receivers were spaced every 0.9 km (1.3 times the theoretical maximum). Higher starting frequencies than 3.0 Hz again led to unacceptable degradation of the results.

Evaluation of glucose as a cryoprotectant for boar semen.

PubMed

De los Reyes, M; Saenz, L; Lapierre, L; Crosby, J; Barros, C

2002-10-19

Fertility parameters of boar spermatozoa were evaluated in vitro, after freeze-thawing the semen in three different extenders containing permeable and non-permeable cryoprotectants: A (111.0 mM Tris, 31.4 mM citric acid, 185.0 mM glucose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G); B (200 mM Tris; 70.8 mM citric acid, 55.5 mM glucose, 20 per cent egg yolk, three per cent glycerol and 100 iu/ml penicillin G); C (200 mM Tris, 70.8 mM citric acid, 55.5 mM fructose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G). The freeze-thawing techniques were the same for each extender. Eight ejaculates from four boars were obtained; the sperm-rich fraction of each ejaculate was extended in each of the three media at a final concentration of 400 x 106 sperm/ml, loaded into 0.5 ml straws and frozen at a rate of 30 degrees C/minute to -196 degrees C. The straws were thawed at 60 degrees C for eight seconds. Sperm motility, acrosomal integrity and in vitro sperm penetration through the zona pellucida of gilt oocytes matured in vitro were evaluated. The motility of unfrozen spermatozoa was 93.1 per cent compared with 60.7 per cent, 48.2 per cent and 35 per cent for sperm frozen in extenders A, B and C respectively; these values were all significantly different (P<0.05). There was no significant decline in sperm motility after incubation for 30 minutes in extender A, but there were significant decreases in sperm motility after 30 minutes of incubation in B and C. The percentage acrosomal integrities were 97.2 per cent for the control and 45.5 per cent, 30.3 per cent and 16.8 per cent for the frozen-thawed spermatozoa in extenders A, B and C respectively. The results of the in vitro penetration assay were 80.7 per cent when using control spermatozoa, and 42.2 per cent, 18.4 per cent and 3.3 per cent when using frozen-thawed spermatozoa in extenders A, B and C respectively

Prevalence of bovine milk pathogens in Azorean pastures: mobile versus fixed milking machines.

PubMed

Azevedo, C; Pacheco, D; Soares, L; Moitoso, M; Maldonado, J; Guix, R; Simões, J

2016-01-01

The aims of the present study were (1) to evaluate the influence of using mobile (n=47) or fixed (n=45) milking machines in Azorean herds on the apparent prevalence of several milk pathogens in bulk tank milk (BTM) and (2) to determine whether separated subclinical mastitic cows can serve, in real time, as predictors of milk pathogen prevalence for the remaining animals at the herd level. The use of a mobile or fixed milking machine influenced (P≤0.05) the prevalence of Staphylococcus aureus (72.3 per cent; n=34 v 51.1 per cent; n=23, respectively) and Klebsiella species (46.8 per cent; n=22 v 26.7 per cent; n=12, respectively). S aureus (95 per cent CI OR 1.1 to 6.0) and Klebsiella species (95 per cent CI OR 1.0 to 5.8) were 2.5 times more likely to increase in the BTM of herds using mobile milking machines. The prevalence of coagulase-negative staphylococci (100 per cent; n=92), Escherichia coli (75.0 per cent), Corynebacterium bovis (57.6 per cent), Enterococcus species (55.4 per cent), Streptococcus dysgalactiae (51.1 per cent), Streptococcus uberis (41.3 per cent), Actinomyces pyogenes or Peptostreptococcus indolicus (41.3 per cent) and Streptococcus agalactiae (32.6 per cent) in BTM remained similar among the herds. κ coefficients were always <0.70, indicating intra-herd disagreement of the prevalence of milk pathogens between BTM and separated milking cows. Milking hygiene should be improved in pastures, focusing specifically on herds that use a mobile milking machine. The segregated cows at milking time are not good predictors of milk pathogens in BTM.

Research and Development on Titanium Alloys

DTIC Science & Technology

1949-08-31

present contract was submitted in lieu of the first regular bimonthly progress report. The attached report contains an account of the following: 1 . A...and 5 to 11 per cent, respectively. l. Titanium - 5 per cent molybdenum base alloys with additions of 1 per cent copper, 2 per cent copper, 1 per...cent manganese, and 2 per cent iron, BATTELLE MEMORIAL INSTITUTE TABLE OF CONTENTS SUMMARY. ** * se0* .0. • • 0000 0 C 0, 00 1 INTRODUCTION. . . o

Pre- and post-operative dizziness, tinnitus, and taste disturbances among cochlear implant recipients.

PubMed

Mikkelsen, K S; Ovesen, T; Swan, C Z

2017-04-01

To determine the pre- and post-operative prevalence of dizziness, tinnitus and taste disturbances in adult cochlear implant recipients. A questionnaire regarding pre- and post-operative dizziness, tinnitus and taste disturbances was sent to 170 cochlear implant recipients implanted between January 2003 and March 2009. Seventy-seven patients (41 per cent) responded. Pre-operatively, 20 per cent of the participants experienced dizziness, 52 per cent experienced tinnitus and 3 per cent experienced taste disturbances. Post-operative dizziness developed in 46 per cent of patients and resolved in the majority of these; however, 15 per cent reported dizziness more than six months after implantation. Tinnitus worsened in 25 per cent of patients, whereas 73 per cent reported attenuation or termination of tinnitus. Post-operatively, tinnitus developed in 12 per cent and taste disturbances developed in 17 per cent of the patients. The high prevalence of dizziness, tinnitus and taste disturbances reported by cochlear implant recipients necessitates that assessment of symptoms related to inner ear and chorda tympani damage are included when evaluating operative results.

Herpes simplex virus proctitis in homosexual men. Clinical, sigmoidoscopic, and histopathological features.

PubMed

Goodell, S E; Quinn, T C; Mkrtichian, E; Schuffler, M D; Holmes, K K; Corey, L

1983-04-14

Acute herpes simplex virus (HSV) infection was detected in 23 of 102 consecutively examined, sexually active male homosexuals who presented with anorectal pain, discharge, tenesmus, or hematochezia, as compared with 3 of 75 homosexual men without gastrointestinal symptoms (P less than 0.01). Findings that were significantly more frequent in men with HSV proctitis than in men with proctitis due to other infectious causes included fever (48 per cent), difficulty in urinating (48 per cent), sacral paresthesias (26 per cent), inguinal lymphadenopathy (57 per cent), severe anorectal pain (100 per cent), tenesmus (100 per cent), constipation (78 per cent), perianal ulcerations (70 per cent), and the presence of diffuse ulcerative or discrete vesicular or pustular lesions in the distal 5 cm of the rectum (50 per cent). Serologic evidence indicated that 85 per cent of the men with symptomatic HSV proctitis were having their first episode of HSV-2 infection. The diagnosis of HSV proctitis is suggested by the presence of severe anorectal pain, difficulty in urinating, sacral paresthesias or pain, and diffuse ulceration of the distal rectal mucosa.

Rock Fracture Toughness Under Mode II Loading: A Theoretical Model Based on Local Strain Energy Density

NASA Astrophysics Data System (ADS)

Rashidi Moghaddam, M.; Ayatollahi, M. R.; Berto, F.

2018-01-01

The values of mode II fracture toughness reported in the literature for several rocks are studied theoretically by using a modified criterion based on strain energy density averaged over a control volume around the crack tip. The modified criterion takes into account the effect of T-stress in addition to the singular terms of stresses/strains. The experimental results are related to mode II fracture tests performed on the semicircular bend and Brazilian disk specimens. There are good agreements between theoretical predictions using the generalized averaged strain energy density criterion and the experimental results. The theoretical results reveal that the value of mode II fracture toughness is affected by the size of control volume around the crack tip and also the magnitude and sign of T-stress.

Apocalypse soon

NASA Astrophysics Data System (ADS)

Jackson, J. C.

1998-05-01

Based upon a simple vacuum Lagrangian, comprising cosmological and quadratic scalar field terms, a cosmological model is presented the history of which is indistinguishable from that of an innocuous low-density cold dark matter (CDM) universe, but the future of which is very much shorter. For sensible values of the deceleration parameter (0

Surface density: a new parameter in the fundamental metallicity relation of star-forming galaxies

NASA Astrophysics Data System (ADS)

Hashimoto, Tetsuya; Goto, Tomotsugu; Momose, Rieko

2018-04-01

Star-forming galaxies display a close relation among stellar mass, metallicity, and star formation rate (or molecular-gas mass). This is known as the fundamental metallicity relation (FMR) (or molecular-gas FMR), and it has a profound implication on models of galaxy evolution. However, there still remains a significant residual scatter around the FMR. We show here that a fourth parameter, the surface density of stellar mass, reduces the dispersion around the molecular-gas FMR. In a principal component analysis of 29 physical parameters of 41 338 star-forming galaxies, the surface density of stellar mass is found to be the fourth most important parameter. The new 4D fundamental relation forms a tighter hypersurface that reduces the metallicity dispersion to 50 per cent of that of the molecular-gas FMR. We suggest that future analyses and models of galaxy evolution should consider the FMR in a 4D space that includes surface density. The dilution time-scale of gas inflow and the star-formation efficiency could explain the observational dependence on surface density of stellar mass.

Demographic and clinical characteristics of a paediatric low vision population in a low vision clinic in China.

PubMed

Gao, Guohong; Yu, Manrong; Dai, Jinhui; Xue, Feng; Wang, Xiaoying; Zou, Leilei; Chen, Minjie; Ma, Fei

2016-05-01

The aim was to describe the characteristics of the paediatric population attending the low vision clinic of the Eye and ENT Hospital, located in Shanghai, China. The clinical records of all the children attending the low vision clinic of Eye and ENT Hospital affiliated to Fudan University between January 1, 2009 and May 31, 2014 were retrospectively reviewed. The main data analysed were age, gender, education, visual demand, diagnosis, visual acuity and prescription of low vision aids. Of the 162 patients, 104 (64.20 per cent) were male. The age range of the study population was three to 20 years, with a mean of 10.73 ± 5.08 years. There were 43.21 per cent with moderate visual impairment, 26.54 per cent had severe visual impairment and 19.75 per cent were blind. The leading causes of visual impairment were congenital cataract (21.61 per cent), optic atrophy (14.20 per cent), macular dystrophy (11.73 per cent), nystagmus (9.88 per cent) and congenital glaucoma (9.26 per cent). The most frequently prescribed low vision devices for distant and near vision were binocular telescopes (23.57 per cent) and stand magnifiers (22.93 per cent), respectively. Young age (up to six years, 37.93 per cent), high cost (24.14 per cent), cosmetic reasons (17.24 per cent) and inconvenience (13.79 per cent) were the main reasons that children or parents refused to accept useful low vision aids. Congenital and hereditary diseases constituted the major causes of low vision in the study population. Strategies that make good-quality rehabilitation services available, affordable and accessible, especially in developing countries, will have the greatest impact on visual impairment. In China, both urban and rural, the coverage of low vision services should be strengthened. © 2016 The Authors. Clinical and Experimental Optometry © 2016 Optometry Australia.

Systematic review of high-intensity focused ultrasound ablation in the treatment of breast cancer.

PubMed

Peek, M C L; Ahmed, M; Napoli, A; ten Haken, B; McWilliams, S; Usiskin, S I; Pinder, S E; van Hemelrijck, M; Douek, M

2015-07-01

A systematic review was undertaken to assess the clinical efficacy of non-invasive high-intensity focused ultrasound (HIFU) ablation in the treatment of breast cancer. MEDLINE/PubMed library databases were used to identify all studies published up to December 2013 that evaluated the role of HIFU ablation in the treatment of breast cancer. Studies were eligible if they were performed on patients with breast cancer and objectively recorded at least one clinical outcome measure of response (imaging, histopathological or cosmetic) to HIFU treatment. Nine studies fulfilled the inclusion criteria. The absence of tumour or residual tumour after treatment was reported for 95·8 per cent of patients (160 of 167). No residual tumour was found in 46·2 per cent (55 of 119; range 17-100 per cent), less than 10 per cent residual tumour in 29·4 per cent (35 of 119; range 0-53 per cent), and between 10 and 90 per cent residual tumour in 22·7 per cent (27 of 119; range 0-60 per cent). The most common complication associated with HIFU ablation was pain (40·1 per cent) and less frequently oedema (16·8 per cent), skin burn (4·2 per cent) and pectoralis major injury (3·6 per cent). MRI showed an absence of contrast enhancement after treatment in 82 per cent of patients (31 of 38; range 50-100 per cent), indicative of coagulative necrosis. Correlation of contrast enhancement on pretreatment and post-treatment MRI successfully predicted the presence of residual disease. HIFU treatment can induce coagulative necrosis in breast cancers. Complete ablation has not been reported consistently on histopathology and no imaging modality has been able confidently to predict the percentage of complete ablation. Consistent tumour and margin necrosis with reliable follow-up imaging are required before HIFU ablation can be evaluated within large, prospective clinical trials. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Shear wave anisotropy from aligned inclusions: ultrasonic frequency dependence of velocity and attenuation

NASA Astrophysics Data System (ADS)

de Figueiredo, J. J. S.; Schleicher, J.; Stewart, R. R.; Dayur, N.; Omoboya, B.; Wiley, R.; William, A.

2013-04-01

To understand their influence on elastic wave propagation, anisotropic cracked media have been widely investigated in many theoretical and experimental studies. In this work, we report on laboratory ultrasound measurements carried out to investigate the effect of source frequency on the elastic parameters (wave velocities and the Thomsen parameter γ) and shear wave attenuation) of fractured anisotropic media. Under controlled conditions, we prepared anisotropic model samples containing penny-shaped rubber inclusions in a solid epoxy resin matrix with crack densities ranging from 0 to 6.2 per cent. Two of the three cracked samples have 10 layers and one has 17 layers. The number of uniform rubber inclusions per layer ranges from 0 to 100. S-wave splitting measurements have shown that scattering effects are more prominent in samples where the seismic wavelength to crack aperture ratio ranges from 1.6 to 1.64 than in others where the ratio varied from 2.72 to 2.85. The sample with the largest cracks showed a magnitude of scattering attenuation three times higher compared with another sample that had small inclusions. Our S-wave ultrasound results demonstrate that elastic scattering, scattering and anelastic attenuation, velocity dispersion and crack size interfere directly in shear wave splitting in a source-frequency dependent manner, resulting in an increase of scattering attenuation and a reduction of shear wave anisotropy with increasing frequency.

Impact of Schmallenberg virus on British sheep farms during the 2011/2012 lambing season.

PubMed

Harris, K A; Eglin, R D; Hayward, S; Milnes, A; Davies, I; Cook, A J C; Downs, S H

2014-08-16

British sheep farmers were invited to complete a questionnaire about the impact of Schmallenberg virus (SBV) on animal health, welfare and their own emotional wellbeing during the 2011-2012 lambing season, through Defra and Farming Industry websites, letters to farmers who had requested SBV laboratory tests and advertisement at Sheep 2012. The 494 responders included SBV confirmed (positive by RT-PCR) (n=76), SBV suspected by farmer (n=140) or SBV not suspected (n=278). Percentage of barren ewes was similar across SBV groups, however, lamb and ewe losses were higher on responder farms where SBV was confirmed or suspected. The median percentages of all lambs born (and lambs born deformed ) that died within one week of birth was 10.4 per cent (5.5 per cent), 7.0 per cent (2.9 per cent) and 5.3 per cent (0 per cent), respectively, on SBV confirmed, suspected and not suspected farms (P<0.001). Eight to 16 per cent of SBV confirmed or suspected farms reported lamb mortality of ≥40 per cent. Farmer perceived impact was greater where SBV was confirmed or suspected (P<0.001): 25 per cent reported a high impact on emotional wellbeing (4 per cent of SBV not suspected), 13 per cent reported a high impact on flock welfare and financial performance and 6 per cent were less likely to farm sheep next year because of SBV (<2 per cent in SBV not suspected). Overall, SBV impact has been large relative to reported sheep loss. British Veterinary Association.

Impact of Schmallenberg virus on British sheep farms during the 2011/2012 lambing season

PubMed Central

Harris, K. A.; Eglin, R. D.; Hayward, S.; Milnes, A.; Davies, I.; Cook, A. J. C.; Downs, S. H.

2014-01-01

British sheep farmers were invited to complete a questionnaire about the impact of Schmallenberg virus (SBV) on animal health, welfare and their own emotional wellbeing during the 2011–2012 lambing season, through Defra and Farming Industry websites, letters to farmers who had requested SBV laboratory tests and advertisement at Sheep 2012. The 494 responders included SBV confirmed (positive by RT-PCR) (n=76), SBV suspected by farmer (n=140) or SBV not suspected (n=278). Percentage of barren ewes was similar across SBV groups, however, lamb and ewe losses were higher on responder farms where SBV was confirmed or suspected. The median percentages of all lambs born (and lambs born deformed ) that died within one week of birth was 10.4 per cent (5.5 per cent), 7.0 per cent (2.9 per cent) and 5.3 per cent (0 per cent), respectively, on SBV confirmed, suspected and not suspected farms (P<0.001). Eight to 16 per cent of SBV confirmed or suspected farms reported lamb mortality of ≥40 per cent. Farmer perceived impact was greater where SBV was confirmed or suspected (P<0.001): 25 per cent reported a high impact on emotional wellbeing (4 per cent of SBV not suspected), 13 per cent reported a high impact on flock welfare and financial performance and 6 per cent were less likely to farm sheep next year because of SBV (<2 per cent in SBV not suspected). Overall, SBV impact has been large relative to reported sheep loss. PMID:24795165

Theoretical model and experimental investigation of current density boundary condition for welding arc study

NASA Astrophysics Data System (ADS)

Boutaghane, A.; Bouhadef, K.; Valensi, F.; Pellerin, S.; Benkedda, Y.

2011-04-01

This paper presents results of theoretical and experimental investigation of the welding arc in Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes. A theoretical model consisting in simultaneous resolution of the set of conservation equations for mass, momentum, energy and current, Ohm's law and Maxwell equation is used to predict temperatures and current density distribution in argon welding arcs. A current density profile had to be assumed over the surface of the cathode as a boundary condition in order to make the theoretical calculations possible. In stationary GTAW process, this assumption leads to fair agreement with experimental results reported in literature with maximum arc temperatures of ~21 000 K. In contrast to the GTAW process, in GMAW process, the electrode is consumable and non-thermionic, and a realistic boundary condition of the current density is lacking. For establishing this crucial boundary condition which is the current density in the anode melting electrode, an original method is setup to enable the current density to be determined experimentally. High-speed camera (3000 images/s) is used to get geometrical dimensions of the welding wire used as anode. The total area of the melting anode covered by the arc plasma being determined, the current density at the anode surface can be calculated. For a 330 A arc, the current density at the melting anode surface is found to be of 5 × 107 A m-2 for a 1.2 mm diameter welding electrode.

Hypertension in Israeli adolescents: prevalence according to weight, sex and parental origin.

PubMed Central

Shohat, M; Shohat, T; Mimouni, M; Nitzan, M; Danon, Y L

1989-01-01

We studied the prevalence of hypertension in 57,499 male and 35,803 female Israeli military recruits and its relation with sex, weight, and parents' ethnic origin. The overall prevalence of systolic hypertension (greater than 140 mmHg) was 1.75 per cent for males and 0.32 per cent for females. The prevalence of diastolic hypertension (greater than 90 mmHg) was 0.41 per cent for males and 0.06 per cent for females. For males, the prevalence of systolic and diastolic hypertension increased with weight, exponentially. Males of Ashkenazi origin had a significantly higher prevalence of hypertension (systolic 2.52 per cent, diastolic 0.55 per cent) compared with those of Sephardi origin (systolic 1.12 per cent, diastolic 0.3 per cent). The prevalence of adolescents with systolic or diastolic blood pressure greater than the mean +2SD of each weight group ranged between 1.5-2.3 per cent. PMID:2705591

Finance salaries. Account the cost.

PubMed

Robling, Andy

2003-02-06

Post-qualification salaries have increased by 4-7 per cent, a slowdown on last year's figures when increases were often more than 10 per cent. The highest increases this year tended to be in medium-sized trusts where newly qualified accountants' salaries rose 8.2 per cent. Directors of finance in large trusts earn about 20 per cent more than in medium trusts and about 40 per cent more than in small ones. Newly qualified accountants in large trusts earn 5 per cent more than in medium-sized trusts and 13 per cent more than in small ones. The survey is based on an analysis of salaries from Hays' jobs database, and salaries of registered candidates.

Post-operative radiation therapy for advanced-stage oropharyngeal cancer.

PubMed

Hansen, Eric; Panwala, Kathryn; Holland, John

2002-11-01

Between 1985 and 1999, 43 patients with locally-advanced, resectable oropharyngeal cancer were treated with combined surgery and post-operative radiation therapy (RT) at Oregon Health and Science University. Five patients (12 per cent) had Stage III disease and 38 patients (88 per cent) had Stage IV disease. All patients had gross total resections of the primary tumour. Thirty-seven patients had neck dissections for regional disease. RT consisted of a mean tumour-bed dose of 63.0 Gy delivered in 1.8-2.0 Gy fractions over a mean of 49 days. At three- and five-years, the actuarial local control was 96 per cent and the actuarial local/regional control was 80 per cent. The three- and five-year actuarial rates of distant metastases were 41 per cent and 46 per cent, respectively. The actuarial overall survival at three- and five-years was 41 per cent and 34 per cent, respectively. The actuarial rates of progression-free survival were 49 per cent at three-years and 45 per cent at five years. Combined surgery and post-operative RT for advanced-stage oropharyngeal cancer results in excellent local/regional control. This particular group of patients experienced a high-rate of developing distant metastases.

INDIVIDUAL BLOOD DIFFERENCES IN MEXICAN INDIANS, WITH SPECIAL REFERENCE TO THE Rh BLOOD TYPES AND Hr FACTOR

PubMed Central

Wiener, Alexander S.; Zepeda, J. Preciado; Sonn, Eve B.; Polivka, H. R.

1945-01-01

98 Mexican Indians were tested for the blood properties A-B-O, A1-A2, M-N, P, Rh'-Rh''-Rh0-rh, and Hr. Of the 98 Indians, 90.8 per cent belonged to group 0, 6.1 per cent belonged to A1, and 3.1 per cent to group B. There were 61.2 per cent of type M, 3.1 per cent of type N, and 35.7 per cent of type MN. Of the 95 Mexican Indians tested with anti-P serum, 21.1 per cent were found to lack the P agglutinogen. In tests for the Rh blood types, 48.0 per cent of the Indians were found to belong to type Rh1, 9.2 per cent to type Rh2, 41.8 per cent to type Rh1Rh2, and 1 per cent to type Rh0. There were no bloods giving intermediate reactions. Of the 95 Indians tested for the Hr factor 44.2 per cent were found to lack this property. The reactions for the Rh blood types and Hr factor were correlated with each other and the results supported the conclusion of Race et al. that in addition to the six standard allelic genes and the so called intermediate genes, there is one or possibly two genes having the property of determining agglutinogens which react with anti-Rh' and anti-Rh'' sera, but not with anti-Hr serum. This gene (or genes) appears to be relatively common among Mexican Indians (approximately 3.3 per cent) in contrast to its rareness in white individuals. PMID:19871476

[Psychophysiological regin for rehabilition of chronic polydrug users in the Center of the Le Patriarche. 446 cases (author's transl)].

PubMed

Laffont, F; Engelmajer, L; Vourc'h, G; Nahas, G

1980-01-01

From 1974 to 1979, the rehabilitation centers of the association "Le Patriarche" located in the country side of southern France, have received 446 chronic polydrugs users who has consumed at one time or an other cannabis (marihuana, hashish) (87 p. cent), LSD (66 p. cent) and other hallucinogens (35 p. cent), psychodepressants (55 p. cent), psychostimulants (amphetamines, 85 p. cent; cocaïne, 50 p. cent) and opium and its derivatives (brown sugar, 47 p. cent; opiates, 67 p. cent; heroin, 50 p. cent). The dominant addictive drug was heroin and opiates, 52 p. cent, psychodepressants (barbitutiques and benzodiazepines, 33 p. cent, psychostimulants, 15 p. cent. Males were twice as numerous as female. Average age was 21 (range 14-38). Mean duration of drug abuse was 7 years. All these drug abusers display at entrance withdrawal symptoms. These were treated successfully by a drug free, psycho-physiological regimen comprising: 1. An elimination of all psychoactive drugs, including coffee, and alcohol. Tobacco was permitted. 2. Physical therapy (bath, exercise, massage) and forced fluid diuresis. 3. A supportive psychotherapy dispensed by rehabilitated addicts who had undergone successfully a similar regimen. This non-pharmacological method of treating withdrawal symptoms associated with opium, barbiturate and amphetamine addiction, was successful, and was not associated with any major clinical symptoms threatening the vital signs. Mean duration of detoxification was 5 days for opiates, 6 days for amphetamines and 10 days for barbiturates. 78 p. cent of these subjects remained in the centers from 3 months to 2 years, partaking in physical occupational and physiological rehabilitation paograms which allowed then to adopt a drug free life style and prepared them for social reinsertion.

The devil's checkerboard: why cross-correlation delay times require a finite frequency interpretation

NASA Astrophysics Data System (ADS)

Nolet, G.; Mercerat, D.; Zaroli, C.

2012-12-01

We present the first complete test of finite frequency tomography with banana-doughnut kernels, from the generation of seismograms in a 3D model to the final inversion, and are able to lay to rest all of the so-called `controversies' that have slowed down its adoption. Cross-correlation delay times are influenced by energy arriving in a time window that includes later arrivals, either scattered from, or diffracted around lateral heterogeneities. We present here the results of a 3D test in which we generate 1716 seismograms using the spectral element method in a cross-borehole experiment conducted in a checkerboard box. Delays are determined for the broadband signals as well as for five frequency bands (each one octave apart) by cross-correlating seismograms for a homogeneous pattern with those for a checkerboard. The large (10 per cent) velocity contrast and the regularity of the checkerboard pattern causes severe reverberations that arrive late in the cross-correlation window. Data errors are estimated by comparing linearity between delays measured for a model with 10 per cent velocity contrast with those with a 4 per cent contrast. Sensitivity kernels are efficiently computed with ray theory using the `banana-doughnut' kernels from Dahlen et al. (GJI 141:157, 2000). The model resulting from the inversion with a data fit with reduced χ2red=1 shows an excellent correspondence with the input model and allows for a complete validation of the theory. Amplitudes in the (well resolved) top part of the model are close to the input amplitudes. Comparing a model derived from one band only shows the power of using multiple frequency bands in resolving detail - essentially the observed dispersion captures some of the waveform information. Finite frequency theory also allows us to image the checkerboard at some distance from the borehole plane. Most disconcertingly for advocates of ray theory are the results obtained when we interpret cross-correlation delays with ray theory. We shall present an extreme case of the devil's checkerboard (the term is from Jacobsen and Sigloch), in which the sign of the anomalies in the checkerboard is reversed in the ray-theoretical solution, a clear demonstration of the reality of effects of the doughnut hole. We conclude that the test fully validates `banana-doughnut' theory, and disqualifies ray theoretical inversions of cross-correlation delays.

Insecticide susceptibility of Phlebotomus argentipes & assessment of vector control in two districts of West Bengal, India.

PubMed

Kumar, Vijay; Shankar, Lokesh; Kesari, Shreekant; Bhunia, Gouri Shankar; Dinesh, Diwakar Singh; Mandal, Rakesh; Das, Pradeep

2015-08-01

Kala-azar or visceral leishmanisis (VL) is known to be endemic in several States of India including West Bengal (WB). Only meager information is available on the vector dynamics of its vector species, Phlebotomus argentipes particularly in relation to control measure from this State. Hence, a pilot study was undertaken to assess the control strategy and its impact on vector in two endemic districts of WB, India. Two villages each from the two districts, Maldah and Burdwan, were selected for the study. Seasonal variation of sandflies was observed during pre-monsoon, post-monsoon and winter seasons. Susceptibility test of P. argentipes against DDT and bioassay on DDT sprayed wall and on long lasting insecticide nets (LN) Perma Net [®] 2.0 were conducted as per the WHO standard methods. P. argentipes density was high during March to October. Susceptibility status of P. argentipes ranged from 40 to 61.54 per cent. Bioassay test showed 57.89 per cent mortality against LN PermaNet [®] -2.0. and 50 per cent against DDT on wall within 30 min of exposure. Despite the integrated vector management approach, the sandfly population was high in the study area. The reason could be development of resistance in P. argentipes against DDT and low effectiveness of LN PermaNet [®] -2.0. The more pragmatic step will be to conduct large studies to monitor the susceptibility level in P. argentipes against DDT.

Cosmic variance of the galaxy cluster weak lensing signal

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

Gruen, D.; Seitz, S.; Becker, M. R.

Intrinsic variations of the projected density profiles of clusters of galaxies at fixed mass are a source of uncertainty for cluster weak lensing. We present a semi-analytical model to account for this effect, based on a combination of variations in halo concentration, ellipticity and orientation, and the presence of correlated haloes. We calibrate the parameters of our model at the 10 per cent level to match the empirical cosmic variance of cluster profiles at M 200m ≈ 10 14…10 15h –1M ⊙, z = 0.25…0.5 in a cosmological simulation. We show that weak lensing measurements of clusters significantly underestimate massmore » uncertainties if intrinsic profile variations are ignored, and that our model can be used to provide correct mass likelihoods. Effects on the achievable accuracy of weak lensing cluster mass measurements are particularly strong for the most massive clusters and deep observations (with ≈20 per cent uncertainty from cosmic variance alone at M 200m ≈ 10 15h –1M ⊙ and z = 0.25), but significant also under typical ground-based conditions. We show that neglecting intrinsic profile variations leads to biases in the mass-observable relation constrained with weak lensing, both for intrinsic scatter and overall scale (the latter at the 15 per cent level). Furthermore, these biases are in excess of the statistical errors of upcoming surveys and can be avoided if the cosmic variance of cluster profiles is accounted for.« less

How well can charge transfer inefficiency be corrected? A parameter sensitivity study for iterative correction

NASA Astrophysics Data System (ADS)

Israel, Holger; Massey, Richard; Prod'homme, Thibaut; Cropper, Mark; Cordes, Oliver; Gow, Jason; Kohley, Ralf; Marggraf, Ole; Niemi, Sami; Rhodes, Jason; Short, Alex; Verhoeve, Peter

2015-10-01

Radiation damage to space-based charge-coupled device detectors creates defects which result in an increasing charge transfer inefficiency (CTI) that causes spurious image trailing. Most of the trailing can be corrected during post-processing, by modelling the charge trapping and moving electrons back to where they belong. However, such correction is not perfect - and damage is continuing to accumulate in orbit. To aid future development, we quantify the limitations of current approaches, and determine where imperfect knowledge of model parameters most degrades measurements of photometry and morphology. As a concrete application, we simulate 1.5 × 109 `worst-case' galaxy and 1.5 × 108 star images to test the performance of the Euclid visual instrument detectors. There are two separable challenges. If the model used to correct CTI is perfectly the same as that used to add CTI, 99.68 per cent of spurious ellipticity is corrected in our setup. This is because readout noise is not subject to CTI, but gets overcorrected during correction. Secondly, if we assume the first issue to be solved, knowledge of the charge trap density within Δρ/ρ = (0.0272 ± 0.0005) per cent and the characteristic release time of the dominant species to be known within Δτ/τ = (0.0400 ± 0.0004) per cent will be required. This work presents the next level of definition of in-orbit CTI calibration procedures for Euclid.

Cosmic variance of the galaxy cluster weak lensing signal

DOE PAGES

Gruen, D.; Seitz, S.; Becker, M. R.; ...

2015-04-13

Intrinsic variations of the projected density profiles of clusters of galaxies at fixed mass are a source of uncertainty for cluster weak lensing. We present a semi-analytical model to account for this effect, based on a combination of variations in halo concentration, ellipticity and orientation, and the presence of correlated haloes. We calibrate the parameters of our model at the 10 per cent level to match the empirical cosmic variance of cluster profiles at M 200m ≈ 10 14…10 15h –1M ⊙, z = 0.25…0.5 in a cosmological simulation. We show that weak lensing measurements of clusters significantly underestimate massmore » uncertainties if intrinsic profile variations are ignored, and that our model can be used to provide correct mass likelihoods. Effects on the achievable accuracy of weak lensing cluster mass measurements are particularly strong for the most massive clusters and deep observations (with ≈20 per cent uncertainty from cosmic variance alone at M 200m ≈ 10 15h –1M ⊙ and z = 0.25), but significant also under typical ground-based conditions. We show that neglecting intrinsic profile variations leads to biases in the mass-observable relation constrained with weak lensing, both for intrinsic scatter and overall scale (the latter at the 15 per cent level). Furthermore, these biases are in excess of the statistical errors of upcoming surveys and can be avoided if the cosmic variance of cluster profiles is accounted for.« less

Finite grid radius and thickness effects on retarding potential analyzer measured suprathermal electron density and temperature

NASA Technical Reports Server (NTRS)

Knudsen, William C.

1992-01-01

The effect of finite grid radius and thickness on the electron current measured by planar retarding potential analyzers (RPAs) is analyzed numerically. Depending on the plasma environment, the current is significantly reduced below that which is calculated using a theoretical equation derived for an idealized RPA having grids with infinite radius and vanishingly small thickness. A correction factor to the idealized theoretical equation is derived for the Pioneer Venus (PV) orbiter RPA (ORPA) for electron gasses consisting of one or more components obeying Maxwell statistics. The error in density and temperature of Maxwellian electron distributions previously derived from ORPA data using the theoretical expression for the idealized ORPA is evaluated by comparing the densities and temperatures derived from a sample of PV ORPA data using the theoretical expression with and without the correction factor.

Comparison of animal and plant proteins for young pen-reared bobwhite quail

USGS Publications Warehouse

Nestler, R.B.; Llewellyn, L.M.; Rensberger, M.J.

1945-01-01

Bobwhite quail chicks, when given a choice of balanced diets in which the essential difference was the protein supplement, showed preferences for one diet containing 49 per cent peanut oil meal, another containing a mixture of 9 per cent meat and bone scraps (50% protein) with 38 per cent soybean oil meal, and a third (control) diet containing a mixture of 16 per cent dried buttermilk with 42 per cent soybean oil meal, in contrast to diets containing sardine meal or menhaden fish meal. ....Feeding tests during the first five weeks of life showed that diets containing 14 per cent sardine fish meal consistently gave high live weights, low mortality, and high efficiency of feed utilization. Diets with 9 to 10 per cent menhaden meal produced nearly as good results....Live weights, survival, and efficiency of feed utilization were markedly better on a diet containing 9 per cent meat and bone scrap (50% protein) than on one with 9 per cent meat scrap (55% protein), but not as good as with diets containing fish meal without meat....The chicks grew and survived more successfully on diets containing either soybean oil meal or peanut oil meal as the sole protein supplement, than on diets containing either linseed oil meal, cottonseed oil meal, or dried buttermilk as the sole protein concentrate. None of these was as satisfactory as the diets containing fish meal.....All chicks died on diets containing either linseed oil meal, cottonseed oil meal, or dried buttermilk as the sole source of protein. All three of these concentrates, however, gave satisfactory results, when used as 10 per cent of the diet. In fact, survival and efficiency of feed utilization were nearly as good on a diet containing 10 per cent dried buttermilk, 10 per cent linseed oil meal, 10 per cent peanut oil meal, and 27 per cent soybean oil meal, as on diets containing fish meal.

Migratory fish, a problem of interstate cooperation?

USGS Publications Warehouse

Van Oosten, John; Adams, William C.; Finley, William L.; Westerman, Fred A.

1939-01-01

Bobwhite quail chicks, when given a choice of balanced diets in which the essential difference was the protein supplement, showed preferences for one diet containing 49 per cent peanut oil meal, another containing a mixture of 9 per cent meat and bone scraps (50% protein) with 38 per cent soybean oil meal, and a third (control) diet containing a mixture of 16 per cent dried buttermilk with 42 per cent soybean oil meal, in contrast to diets containing sardine meal or menhaden fish meal. ....Feeding tests during the first five weeks of life showed that diets containing 14 per cent sardine fish meal consistently gave high live weights, low mortality, and high efficiency of feed utilization. Diets with 9 to 10 per cent menhaden meal produced nearly as good results....Live weights, survival, and efficiency of feed utilization were markedly better on a diet containing 9 per cent meat and bone scrap (50% protein) than on one with 9 per cent meat scrap (55% protein), but not as good as with diets containing fish meal without meat....The chicks grew and survived more successfully on diets containing either soybean oil meal or peanut oil meal as the sole protein supplement, than on diets containing either linseed oil meal, cottonseed oil meal, or dried buttermilk as the sole protein concentrate. None of these was as satisfactory as the diets containing fish meal.....All chicks died on diets containing either linseed oil meal, cottonseed oil meal, or dried buttermilk as the sole source of protein. All three of these concentrates, however, gave satisfactory results, when used as 10 per cent of the diet. In fact, survival and efficiency of feed utilization were nearly as good on a diet containing 10 per cent dried buttermilk, 10 per cent linseed oil meal, 10 per cent peanut oil meal, and 27 per cent soybean oil meal, as on diets containing fish meal.

Epidemiology of burns due to domestic flammable agents.

PubMed

Pegg, S P; Beecham, L; Dore, N; Hrdlicka, D; Hukins, C

1990-04-01

An analysis of the epidemiological factors relating to domestic flammable agents has shown that 17.7 per cent of admissions over a 5-year period were involved in domestic flammable injuries; 87.7 per cent of the patients were male, with 38.9 per cent being young males between 12 and 19 years old. Petrol and diesel accounted for 56.8 per cent of the burns and the average body surface area burned was 17.7 per cent. Most commonly the face, hands and limbs were burned, and the average length of stay was 18.25 days, 69.2 per cent of the burns were due to human error and were thus potentially preventable, 21.2 per cent had predisposing conditions with 8.9 per cent being due to alcohol. It was considered that the strategies to prevent these burns injuries should be aimed particularly at young males.

Evolution of the polarization of the optical afterglow of the gamma-ray burst GRB030329.

PubMed

Greiner, Jochen; Klose, Sylvio; Reinsch, Klaus; Schmid, Hans Martin; Sari, Re'em; Hartmann, Dieter H; Kouveliotou, Chryssa; Rau, Arne; Palazzi, Eliana; Straubmeier, Christian; Stecklum, Bringfried; Zharikov, Sergej; Tovmassian, Gaghik; Bärnbantner, Otto; Ries, Christoph; Jehin, Emmanuel; Henden, Arne; Kaas, Anlaug A; Grav, Tommy; Hjorth, Jens; Pedersen, Holger; Wijers, Ralph A M J; Kaufer, Andreas; Park, Hye-Sook; Williams, Grant; Reimer, Olaf

2003-11-13

The association of a supernova with GRB030329 strongly supports the 'collapsar' model of gamma-ray bursts, where a relativistic jet forms after the progenitor star collapses. Such jets cannot be spatially resolved because gamma-ray bursts lie at cosmological distances; their existence is instead inferred from 'breaks' in the light curves of the afterglows, and from the theoretical desire to reduce the estimated total energy of the burst by proposing that most of it comes out in narrow beams. Temporal evolution of the polarization of the afterglows may provide independent evidence for the jet structure of the relativistic outflow. Small-level polarization ( approximately 1-3 per cent) has been reported for a few bursts, but its temporal evolution has yet to be established. Here we report polarimetric observations of the afterglow of GRB030329. We establish the polarization light curve, detect sustained polarization at the per cent level, and find significant variability. The data imply that the afterglow magnetic field has a small coherence length and is mostly random, probably generated by turbulence, in contrast with the picture arising from the high polarization detected in the prompt gamma-rays from GRB021206 (ref. 18).

Helium in the eroding atmosphere of an exoplanet

NASA Astrophysics Data System (ADS)

Spake, J. J.; Sing, D. K.; Evans, T. M.; Oklopčić, A.; Bourrier, V.; Kreidberg, L.; Rackham, B. V.; Irwin, J.; Ehrenreich, D.; Wyttenbach, A.; Wakeford, H. R.; Zhou, Y.; Chubb, K. L.; Nikolov, N.; Goyal, J. M.; Henry, G. W.; Williamson, M. H.; Blumenthal, S.; Anderson, D. R.; Hellier, C.; Charbonneau, D.; Udry, S.; Madhusudhan, N.

2018-05-01

Helium is the second-most abundant element in the Universe after hydrogen and is one of the main constituents of gas-giant planets in our Solar System. Early theoretical models predicted helium to be among the most readily detectable species in the atmospheres of exoplanets, especially in extended and escaping atmospheres1. Searches for helium, however, have hitherto been unsuccessful2. Here we report observations of helium on an exoplanet, at a confidence level of 4.5 standard deviations. We measured the near-infrared transmission spectrum of the warm gas giant3 WASP-107b and identified the narrow absorption feature of excited metastable helium at 10,833 angstroms. The amplitude of the feature, in transit depth, is 0.049 ± 0.011 per cent in a bandpass of 98 angstroms, which is more than five times greater than what could be caused by nominal stellar chromospheric activity. This large absorption signal suggests that WASP-107b has an extended atmosphere that is eroding at a total rate of 1010 to 3 × 1011 grams per second (0.1-4 per cent of its total mass per billion years), and may have a comet-like tail of gas shaped by radiation pressure.

Income distribution trends and future food demand.

PubMed

Cirera, Xavier; Masset, Edoardo

2010-09-27

This paper surveys the theoretical literature on the relationship between income distribution and food demand, and identifies main gaps of current food modelling techniques that affect the accuracy of food demand projections. At the heart of the relationship between income distribution and food demand is Engel's law. Engel's law establishes that as income increases, households' demand for food increases less than proportionally. A consequence of this law is that the particular shape of the distribution of income across individuals and countries affects the rate of growth of food demand. Our review of the literature suggests that existing models of food demand fail to incorporate the required Engel flexibility when (i) aggregating different food budget shares among households; and (ii) changing budget shares as income grows. We perform simple simulations to predict growth in food demand under alternative income distribution scenarios taking into account nonlinearity of food demand. Results suggest that (i) distributional effects are to be expected from changes in between-countries inequality, rather than within-country inequality; and (ii) simulations of an optimistic and a pessimistic scenario of income inequality suggest that world food demand in 2050 would be 2.7 per cent higher and 5.4 per cent lower than distributional-neutral growth, respectively.

A Study to Determine Whether Nurse Practitioners are Appropriately Utilized at Moncrief Army Hospital, Fort Jackson, South Carolina

DTIC Science & Technology

1981-08-01

cent are family practice, 17.6 per cent are adult medicine, 10.7 per cent are maternity, 8.4 per cent are midwifery , 13 and 3 per cent are psychiatric...authority to prescribe drugs listed in the algorithm. 15 The Physician Assistants (PA) are corpsmen who are given a two year 5 training program and

Evidence for a maximum mass cut-off in the neutron star mass distribution and constraints on the equation of state

NASA Astrophysics Data System (ADS)

Alsing, Justin; Silva, Hector O.; Berti, Emanuele

2018-07-01

We infer the mass distribution of neutron stars in binary systems using a flexible Gaussian mixture model and use Bayesian model selection to explore evidence for multimodality and a sharp cut-off in the mass distribution. We find overwhelming evidence for a bimodal distribution, in agreement with previous literature, and report for the first time positive evidence for a sharp cut-off at a maximum neutron star mass. We measure the maximum mass to be 2.0 M⊙ < mmax < 2.2 M⊙ (68 per cent), 2.0 M⊙ < mmax < 2.6 M⊙ (90 per cent), and evidence for a cut-off is robust against the choice of model for the mass distribution and to removing the most extreme (highest mass) neutron stars from the data set. If this sharp cut-off is interpreted as the maximum stable neutron star mass allowed by the equation of state of dense matter, our measurement puts constraints on the equation of state. For a set of realistic equations of state that support >2 M⊙ neutron stars, our inference of mmax is able to distinguish between models at odds ratios of up to 12:1, whilst under a flexible piecewise polytropic equation-of-state model our maximum mass measurement improves constraints on the pressure at 3-7× the nuclear saturation density by ˜ 30-50 per cent compared to simply requiring mmax > 2 M⊙. We obtain a lower bound on the maximum sound speed attained inside the neutron star of c_ s^max > 0.63c (99.8 per cent), ruling out c_ s^max < c/√{3} at high significance. Our constraints on the maximum neutron star mass strengthen the case for neutron star-neutron star mergers as the primary source of short gamma-ray bursts.

Finding counterparts for all-sky X-ray surveys with NWAY: a Bayesian algorithm for cross-matching multiple catalogues

NASA Astrophysics Data System (ADS)

Salvato, M.; Buchner, J.; Budavári, T.; Dwelly, T.; Merloni, A.; Brusa, M.; Rau, A.; Fotopoulou, S.; Nandra, K.

2018-02-01

We release the AllWISE counterparts and Gaia matches to 106 573 and 17 665 X-ray sources detected in the ROSAT 2RXS and XMMSL2 surveys with |b| > 15°. These are the brightest X-ray sources in the sky, but their position uncertainties and the sparse multi-wavelength coverage until now rendered the identification of their counterparts a demanding task with uncertain results. New all-sky multi-wavelength surveys of sufficient depth, like AllWISE and Gaia, and a new Bayesian statistics based algorithm, NWAY, allow us, for the first time, to provide reliable counterpart associations. NWAY extends previous distance and sky density based association methods and, using one or more priors (e.g. colours, magnitudes), weights the probability that sources from two or more catalogues are simultaneously associated on the basis of their observable characteristics. Here, counterparts have been determined using a Wide-field Infrared Survey Explorer (WISE) colour-magnitude prior. A reference sample of 4524 XMM/Chandra and Swift X-ray sources demonstrates a reliability of ∼94.7 per cent (2RXS) and 97.4 per cent (XMMSL2). Combining our results with Chandra-COSMOS data, we propose a new separation between stars and AGN in the X-ray/WISE flux-magnitude plane, valid over six orders of magnitude. We also release the NWAY code and its user manual. NWAY was extensively tested with XMM-COSMOS data. Using two different sets of priors, we find an agreement of 96 per cent and 99 per cent with published Likelihood Ratio methods. Our results were achieved faster and without any follow-up visual inspection. With the advent of deep and wide area surveys in X-rays (e.g. SRG/eROSITA, Athena/WFI) and radio (ASKAP/EMU, LOFAR, APERTIF, etc.) NWAY will provide a powerful and reliable counterpart identification tool.

31 CFR 82.2 - Exceptions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... exportation of 5-cent coins and one-cent coins carried on an individual, or in the personal effects of an... incidental to the recycling of other materials so long as— (1) Such 5-cent and one-cent coins were not added...

Retrospective study of congenital heart defects in 151 dogs.

PubMed

Tidholm, A

1997-03-01

The case records of 151 dogs diagnosed with congenital heart disease were reviewed retrospectively. The most common defect was aortic stenosis, accounting for 35 per cent of all cases, followed by pulmonic stenosis (20 per cent), ventricular septal defect (12 per cent), patent ductus arteriosus (11 per cent), mitral valve dysplasia (8 per cent), tricuspid valve dysplasia (7 per cent), endocardial fibroelastosis (1.9 per cent) and tetralogy of Fallot (0.6 per cent). Fifty-one breeds were represented, with golden retrievers, German shepherd dogs and boxers predominating. No overall sex predilection was obvious. Seventy-five per cent of the dogs were asymptomatic at presentation. The defects most often associated with presenting symptoms, such as dyspnoea, syncope, ascites, failure to grow and depression, were mitral valve dysplasia, atrial septal defect, tricuspid valve dysplasia and endocardial fibroelastosis. The latter presented with the most severe signs of heart failure. In some cases of aortic stenosis and pulmonic stenosis, where the defect could not be accurately visualised with two-dimensional echocardiography, Doppler echocardiographic examination was needed for definitive diagnosis.

Submm/mm galaxy counterpart identification using a characteristic density distribution

NASA Astrophysics Data System (ADS)

Alberts, Stacey; Wilson, Grant W.; Lu, Yu; Johnson, Seth; Yun, Min S.; Scott, Kimberly S.; Pope, Alexandra; Aretxaga, Itziar; Ezawa, Hajime; Hughes, David H.; Kawabe, Ryohei; Kim, Sungeun; Kohno, Kotaro; Oshima, Tai

2013-05-01

We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (˜18 arcsec), this technique identifies ˜85 per cent of SMG counterparts. For much larger beam sizes (≳30 arcsec), we report identification rates of 33-49 per cent. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope.

A rocky planet transiting a nearby low-mass star.

PubMed

Berta-Thompson, Zachory K; Irwin, Jonathan; Charbonneau, David; Newton, Elisabeth R; Dittmann, Jason A; Astudillo-Defru, Nicola; Bonfils, Xavier; Gillon, Michaël; Jehin, Emmanuël; Stark, Antony A; Stalder, Brian; Bouchy, Francois; Delfosse, Xavier; Forveille, Thierry; Lovis, Christophe; Mayor, Michel; Neves, Vasco; Pepe, Francesco; Santos, Nuno C; Udry, Stéphane; Wünsche, Anaël

2015-11-12

M-dwarf stars--hydrogen-burning stars that are smaller than 60 per cent of the size of the Sun--are the most common class of star in our Galaxy and outnumber Sun-like stars by a ratio of 12:1. Recent results have shown that M dwarfs host Earth-sized planets in great numbers: the average number of M-dwarf planets that are between 0.5 to 1.5 times the size of Earth is at least 1.4 per star. The nearest such planets known to transit their star are 39 parsecs away, too distant for detailed follow-up observations to measure the planetary masses or to study their atmospheres. Here we report observations of GJ 1132b, a planet with a size of 1.2 Earth radii that is transiting a small star 12 parsecs away. Our Doppler mass measurement of GJ 1132b yields a density consistent with an Earth-like bulk composition, similar to the compositions of the six known exoplanets with masses less than six times that of the Earth and precisely measured densities. Receiving 19 times more stellar radiation than the Earth, the planet is too hot to be habitable but is cool enough to support a substantial atmosphere, one that has probably been considerably depleted of hydrogen. Because the host star is nearby and only 21 per cent the radius of the Sun, existing and upcoming telescopes will be able to observe the composition and dynamics of the planetary atmosphere.

MICROSCOPIC DETERMINATION OF BONE PHOSPHORUS BY QUANTITATIVE AUTORADIOGRAPHY OF NEUTRON-ACTIVATED SECTIONS

PubMed Central

Vincent, Jacques; Haumont, Stanislas; Roels, Joseph

1965-01-01

Longitudinal sections of human cortical bone were submitted to thermal neutrons. γ-ray spectra were recorded repeatedly during 15 days following irradiation. They showed that Na24 is predominant as early as 3 hours after activation and that all the γ-emitters have decayed on the 15th day. When the γ-rays have disappeared, β-rays are still produced by the sections. It was proved by the absorption curve in aluminium that all these β-rays are issued from the P32 induced in the sections by activation of P31. Therefore autoradiograms registered 15 days after activation reveal the distribution of P32 in the sections. γ-ray spectra and β-ray absorption curves of neutron activated sections of ivory demonstrated a mineral composition similar to that of bone. Autoradiograms of ivory sections activated for various times were used to establish the relation between the optical density of the autoradiograms and the radioactivity in P32. When the bone autoradiograms are compared with the ivory standards of known radioactivity, the optical densities of single osteons (Haversian systems), can be related to their phosphorus contents. Autoradiograms and microradiograms of the same sections were examined side by side. The least calcified osteons, that contain 80 per cent of the calcium of the fully calcified osteons, also contain about 80 per cent of the phosphorus of the fully mineralized osteons. It is concluded that the Ca:P ratio remains constant while mineralization of bone tissue is being completed. PMID:14286295

Prevalence of self-reported depressive symptoms in young adolescents.

PubMed Central

Schoenbach, V J; Kaplan, B H; Wagner, E H; Grimson, R C; Miller, F T

1983-01-01

To investigate the significance and measurement of depressive symptoms in young adolescents, 624 junior high school students were asked to complete the Center for Epidemiologic Studies Depression Scale (CES-D) during home interviews. In 384 usable symptom scales, item-scale correlations (most were above .50), inter-item correlations, coefficient alpha (.85), and patterns of reported symptoms were reasonable. Persistent symptoms were reported more often by Blacks, especially Black males. Prevalence of persistent symptoms in Whites was quite close to reported figures for adults, ranging from 1 per cent to 15 per cent in adolescent males and 2 per cent to 13 per cent in adolescent females. Adolescents reported persistent vegetative symptoms less often and psychosocial symptoms more often. Reports of symptoms without regard to duration were much more frequent in the adolescents, ranging from 18 per cent to 76 per cent in White males, 34 per cent to 76 per cent in White and Black females, and 41 per cent to 85 per cent in Black males. The results support the feasibility of using a self-report symptom scale to measure depressive symptoms in young adolescents. Transient symptoms reported by adolescents probably reflect their stage of development, but persistent symptoms are likely to have social psychiatric importance. PMID:6625033

Survey of the provision of prophylactic dental care for horses in Great Britain and Ireland between 1999 and 2002.

PubMed

Dixon, P M; Andrew, R; Brannon, H; Burgess, R; Gibson, A; Little, J C; Orange, B; Ross, L; Rudolph, T; Shaw, D J

2004-11-27

A survey of 854 horse owners, trainers and equestrian managers in 10 regions of Great Britain and Ireland showed that 83 per cent provided their horses with routine prophylactic dental care at fixed intervals, including 49 per cent at intervals of 12 months and 30 per cent at intervals of six months; a further 10 per cent provided it only when they felt it was required and 7 per cent did not provide it at all. Overall, 44 per cent of the owners had their horse's wolf teeth (first premolar) extracted routinely; when prophylactic dentistry was provided, it was carried out solely by equine dental technicians (EDTS) for 53 per cent of owners, solely by veterinarians for 35 per cent, by both EDTS or veterinarians for 10 per cent of owners and by other than veterinarians or EDTS for 1 per cent. There was confusion among some horse owners concerning the qualifications of the EDTS, because no recognised British qualification was available until towards the end of this survey in 2001. Several reasons were cited by owners for choosing between veterinarians and EDTS including their perceived qualifications, personal recommendations, costs, the availability of a wide range of dental equipment and sedation, and the time and effort devoted to the procedures.

Attitudes toward euthanasia, assisted suicide and termination of life-sustaining treatment of Puerto Rican medical students, medical residents, and faculty.

PubMed

Ramirez Rivera, J; Rodríguez, R; Otero Igaravidez, Y

2000-01-01

To elicit the opinion of Puerto Rican medical students, residents and internal medicine faculty as to the appropriateness of euthanasia and physician-assisted suicide and end-of-life management. Survey using a 16-item questionnaire answered within a two-month period in the fall of 1996. Rounds or faculty meetings at teaching hospitals located in the north, south and southwest of the island of Puerto Rico. There were 424 participants. The questionnaires of 279 medical students, 75 medical residents, and 35 internal medicine faculty members were analyzed. Thirty-five questionnaires, which were incomplete or answered by non-Puerto Rican participants, were excluded. Frequency of support of active euthanasia, physician-assisted suicide, withholding or withdrawing life-sustaining treatment with informed consent was determined. Whether it was ethical to prescribe full doses of drugs needed to alleviate pain even if it would hasten death, or agree to limit or restrict resources for the terminally ill was also determined. Forty per cent of the students, 33% of the residents, and 20% of the faculty supported euthanasia. If physician-assisted suicide were legalized, 50 per cent of the students, 43 per cent of the residents and 45 percent of the faculty would not be opposed to it. Sixty-eight per cent of the students, 67 per cent of the residents and 88 per cent of the faculty would support withholding or withdrawing life-sustaining treatment for dying patients with informed consent. Seventy-nine per cent of residents, 80 per cent of the faculty but only 54 per cent of medical students would prescribe full doses of drugs needed to alleviate pain in dying patients even if they would hasten death. Thirty-six per cent of the residents and faculty would agree to limit the use of medical resources for the terminally ill but only sixteen per cent of medical students would do so. The acceptance of euthanasia was inversely proportional to the clinical experience of the respondents: 40 per cent among students but only 20 per cent by the faculty. Withholding and withdrawing of life-sustaining treatment was most acceptable to the faculty (88 per cent) but it was also favored by most of the students and residents (68 and 67 per cent respectively). Eighty per cent of the faculty, 79 per cent of the residents, but only 50 per cent of the students considered that prescribing full doses of drugs to alleviate pain if they knew it would hasten death, was ethical. The medical profession should take notice of evolving concepts in end-of-life management.

Chemical composition of phosphorites of the Phosphoria Formation

USGS Publications Warehouse

Gulbrandsen, R.A.

1966-01-01

The chemical composition, both major and minor constituents, of 60 samples of phosphorite from the Phosphoria Formation was determined. Major constituents of the average phosphorite are, by weight per cent: SiO2, 11??9; Al2O3, 1??7; Fe2O3,1??1; MgO, 0??3; CaO, 44??0; Na2O, 0??6; K2O, 0??5; total H2O, 2??2; H2O-, 0??6; TiO2, 0??1; P2O5, 30??5; CO2, 2??2; SO3, 1??8; F, 3??1; organic matter, 2??1; and oil, 0??2. Uranium averages 0??009 per cent. The phosphate mineral is basically apatite, Ca5(PO4)3F, with small but significant and variable substitutions-Na, Sr, U and Th for Ca, and CO3 and SO4 for PO4. Rare metals not associated with apatite are associated principally with the organic-matter component of the rocks. This group includes As, Ag, Cd, Cr, Cu, Mo, Ni, Sb, Se, V and Zn. Chromium is the most abundant, having a modal abundance of 0??1 per cent and a maximum concentration of 0??3 per cent. The average phosphorite is composed of approximately 80 per cent apatite, 10 per cent quartz, 5 per cent muscovite-illite, 2 per cent organic matter, 1 per cent dolomite-calcite, 1 per cent iron oxide, and 1 per cent other components. It is texturally a medium-grained pellet phosphorite. ?? 1966.

Experimental and theoretical charge density studies at subatomic resolution.

PubMed

Fischer, A; Tiana, D; Scherer, W; Batke, K; Eickerling, G; Svendsen, H; Bindzus, N; Iversen, B B

2011-11-17

Analysis of accurate experimental and theoretical structure factors of diamond and silicon reveals that the contraction of the core shell due to covalent bond formation causes significant perturbations of the total charge density that cannot be ignored in precise charge density studies. We outline that the nature and origin of core contraction/expansion and core polarization phenomena can be analyzed by experimental studies employing an extended Hansen-Coppens multipolar model. Omission or insufficient treatment of these subatomic charge density phenomena might yield erroneous thermal displacement parameters and high residual densities in multipolar refinements. Our detailed studies therefore suggest that the refinement of contraction/expansion and population parameters of all atomic shells is essential to the precise reconstruction of electron density distributions by a multipolar model. Furthermore, our results imply that also the polarization of the inner shells needs to be adopted, especially in cases where second row or even heavier elements are involved in covalent bonding. These theoretical studies are supported by direct multipolar refinements of X-ray powder diffraction data of diamond obtained from a third-generation synchrotron-radiation source (SPring-8, BL02B2).

Peculiarities in velocity dispersion and surface density profiles of star clusters

NASA Astrophysics Data System (ADS)

Küpper, Andreas H. W.; Kroupa, Pavel; Baumgardt, Holger; Heggie, Douglas C.

2010-10-01

Based on our recent work on tidal tails of star clusters we investigate star clusters of a few 104Msolar by means of velocity dispersion profiles and surface density profiles. We use a comprehensive set of N-body computations of star clusters on various orbits within a realistic tidal field to study the evolution of these profiles with time, and ongoing cluster dissolution. From the velocity dispersion profiles we find that the population of potential escapers, i.e. energetically unbound stars inside the Jacobi radius, dominates clusters at radii above about 50 per cent of the Jacobi radius. Beyond 70 per cent of the Jacobi radius nearly all stars are energetically unbound. The velocity dispersion therefore significantly deviates from the predictions of simple equilibrium models in this regime. We furthermore argue that for this reason this part of a cluster cannot be used to detect a dark matter halo or deviations from the Newtonian gravity. By fitting templates to about 104 computed surface density profiles we estimate the accuracy which can be achieved in reconstructing the Jacobi radius of a cluster in this way. We find that the template of King works well for extended clusters on nearly circular orbits, but shows significant flaws in the case of eccentric cluster orbits. This we fix by extending this template with three more free parameters. Our template can reconstruct the tidal radius over all fitted ranges with an accuracy of about 10 per cent, and is especially useful in the case of cluster data with a wide radial coverage and for clusters showing significant extra-tidal stellar populations. No other template that we have tried can yield comparable results over this range of cluster conditions. All templates fail to reconstruct tidal parameters of concentrated clusters, however. Moreover, we find that the bulk of a cluster adjusts to the mean tidal field which it experiences and not to the tidal field at perigalacticon as has often been assumed in other investigations, i.e. a fitted tidal radius is a cluster's time average mean tidal radius and not its perigalactic one. Furthermore, we study the tidal debris in the vicinity of the clusters and find it to be well represented by a power law with a slope of -4 to -5. This steep slope we ascribe to the epicyclic motion of escaped stars in the tidal tails. Star clusters close to apogalacticon show a significantly shallower slope of up to -1, however. We suggest that clusters at apogalacticon can be identified by measuring this slope.

Anatrophic nephrolithotomy for removal of staghorn or branched renal calculi.

PubMed

James, R; Novick, A C; Straffon, R A; Stewart, B H

1980-02-01

Forty anatrophic nephrolithotomies were performed in 38 patients between November, 1965, and December, 1977, to remove staghorn or branched renal calculi. Thirty-six (95 per cent) of the patients' preoperative urine cultures were infected, and postoperatively 35 of the cultures (88 per cent) were sterile. Magnesium ammonium phosphate calculi were present in the majority of patients (67 per cent). In 6 patients (15 per cent) transient nephrocutaneous fistulas developed. Thirty-six of the 40 renal units (90 per cent) had improved or stable intravenous pyelograms postoperatively. The patients had been followed for an average of twenty months (four to one hundred and twelve months). In 6 patients (15 per cent) recurrent renal calculi developed, and 3 patients (8 per cent) had residual calculi during this period.

A 2 per cent distance to z = 0.35 by reconstructing baryon acoustic oscillations - I. Methods and application to the Sloan Digital Sky Survey

NASA Astrophysics Data System (ADS)

Padmanabhan, Nikhil; Xu, Xiaoying; Eisenstein, Daniel J.; Scalzo, Richard; Cuesta, Antonio J.; Mehta, Kushal T.; Kazin, Eyal

2012-12-01

We present the first application to density field reconstruction to a galaxy survey to undo the smoothing of the baryon acoustic oscillation (BAO) feature due to non-linear gravitational evolution and thereby improve the precision of the distance measurements possible. We apply the reconstruction technique to the clustering of galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) luminous red galaxy (LRG) sample, sharpening the BAO feature and achieving a 1.9 per cent measurement of the distance to z = 0.35. We update the reconstruction algorithm of Eisenstein et al. to account for the effects of survey geometry as well as redshift-space distortions and validate it on 160 LasDamas simulations. We demonstrate that reconstruction sharpens the BAO feature in the angle averaged galaxy correlation function, reducing the non-linear smoothing scale Σnl from 8.1 to 4.4 Mpc h-1. Reconstruction also significantly reduces the effects of redshift-space distortions at the BAO scale, isotropizing the correlation function. This sharpened BAO feature yields an unbiased distance estimate (<0.2 per cent) and reduces the scatter from 3.3 to 2.1 per cent. We demonstrate the robustness of these results to the various reconstruction parameters, including the smoothing scale, the galaxy bias and the linear growth rate. Applying this reconstruction algorithm to the SDSS LRG DR7 sample improves the significance of the BAO feature in these data from 3.3σ for the unreconstructed correlation function to 4.2σ after reconstruction. We estimate a relative distance scale DV/rs to z = 0.35 of 8.88 ± 0.17, where rs is the sound horizon and DV≡(DA2H-1)1/3 is a combination of the angular diameter distance DA and Hubble parameter H. Assuming a sound horizon of 154.25 Mpc, this translates into a distance measurement DV(z = 0.35) = 1.356 ± 0.025 Gpc. We find that reconstruction reduces the distance error in the DR7 sample from 3.5 to 1.9 per cent, equivalent to a survey with three times the volume of SDSS.

Antimicrobial resistance and phylogenetic groups in isolates of Escherichia coli from seagulls at the Berlengas nature reserve.

PubMed

Radhouani, H; Poeta, P; Igrejas, G; Gonçalves, A; Vinué, L; Torres, C

2009-08-01

Fifty-three faecal samples from yellow-legged gulls (Larus cachinnans) at the Berlengas nature reserve in Portugal were cultured on Levine agar plates not supplemented with antimicrobial agents, and one Escherichia coli colony was isolated and identified from each sample. The percentages of resistant isolates for each of the drugs were ampicillin (43.4 per cent), tetracycline (39.6 per cent), nalidixic acid (34.0 per cent), streptomycin (32.1 per cent), trimethoprim-sulfamethoxazole (SXT) (26.4 per cent), ciprofloxacin (18.9 per cent), chloramphenicol (18.9 per cent), gentamicin (7.5 per cent), tobramycin (7.5 per cent) amikacin (5.7 per cent) and amoxicillin-clavulanic acid (1.9 per cent). All the isolates were susceptible to cefoxitin, ceftazidime, cefotaxime, aztreonam and imipenem. The following resistance genes were detected: bla(TEM) (17 of 23 ampicillin-resistant isolates), tet(A) and/or tet(B) (18 of 21 tetracycline-resistant isolates), aadA (12 of 17 streptomycin-resistant isolates), cmlA (all chloramphenicol-resistant isolates), aac(3)-II with or without aac(3)-IV (all four gentamicin-resistant isolates), and sul1 and/or sul2 and/or sul3 (all 14 SXT-resistant isolates). The intI1 gene was detected in 10 of 14 SXT-resistant isolates, and three of them also contained class 2 integrons; four different gene cassette arrangements were identified among class 1 integrons (aadA, dfrA1+aadA1, dfrA12+orfF+aadA2 and sat+psp+aadA2) and one among the class 2 integrons (dfrA1+sat+aadA1). Ninety per cent of the isolates were included in the A or B1 phylogenetic groups.

Multi-band polarimetry of post-asymptotic giant branch stars - I. Optical measurements

NASA Astrophysics Data System (ADS)

Akras, S.; Ramírez Vélez, J. C.; Nanouris, N.; Ramos-Larios, G.; López, J. M.; Hiriart, D.; Panoglou, D.

2017-04-01

We present new optical broad-band (UBVRI) aperture polarimetric observations of 53 post-asymptotic giant branch (AGB) stars selected to exhibit a large near-infrared excess. 24 out of the 53 stars (45 per cent of our sample) are presented for the first time. A statistical analysis shows four distinctive groups of polarized post-AGB stars: unpolarized or very lowly polarized (degree of polarization or DoP < 1 per cent), lowly polarized (1 per cent < DoP < 4 per cent), moderately polarized (4 per cent < DoP < 8 per cent) and highly polarized (DoP > 8 per cent). 23 out of the 53 (66 per cent) belong to the first group, 10 (19 per cent) to the second, five (9 per cent) to the third and only three (6 per cent) to the last group. Approximately 34 per cent of our sample was found to be unpolarized objects, which is close to the percentage of round planetary nebulae. On average, the low and moderate groups show a wavelength-dependent polarization that increases towards shorter wavelengths, implying an intrinsic origin of the polarization, which signifies a Rayleigh-like scattering spectrum typical for non-symmetrical envelopes composed principally of small dust grains. The moderately polarized stars exhibit higher K - W3 and W1 - W3 colour indices compared with the group of lowly polarized stars, suggesting a possible relation between DoP and mass-loss rate. Moreover, they are found to be systematically colder (redder in B - V), which may be associated with the condensation process close to these stars that results in a higher degree of polarization. We also provide evidence that multiple scattering in optically thin polar outflows is the mechanism that gives high DoP in post-AGB stars with bipolar or multi-polar envelopes.

Oral rehydration therapy in a rural area, northern Thailand.

PubMed

Varavithya, W; Sangshaisirisak, S; Ramaboot, S; Ruangkanchanasetr, S; Vivatwongkasem, C

1989-01-01

A cross-sectional sampling survey of mothers' practice of ORT in Amphoe Bunpotphesai in the northern part of Thailand included 1,619 children under five. Two hundred and six children were reported to have 223 diarrheal episodes. The incidence of diarrhea in children under five was 3.4 episodes per child per year. When children had diarrhea 65.5 per cent of mothers sought help from health providers, 25.2 per cent treated their children with drugs bought from stores, 2.3 per cent used herbal medicine and 6.1 per cent did not treat their children. 50.7 per cent of diarrheal episodes mother gave ORT, using ORS 19.7, commercial electrolytes mixture 16.6 and home available fluid 14.4 per cent. The accuracy of dilution of electrolytes powder from the packets was checked in 80 incidences. 31.8 and 27.8 per cent of mothers made correct dilution of ORS and commercial electrolytes products respectively. Health providers carried both ORS and commercial electrolytes packets. ORS added to a glass of water was found in 13.6 per cent which was 3 times concentrated. Commercial electrolytes products were too dilute in 72.2 per cent. 17.5 per cent of mothers divided electrolytes powder to add in one spoon of water to treat their children as one drug dose. Data showed that the ORT use rate was 50.7 per cent. Home available fluid was used by 14.4 per cent. ORT should be further promoted to control diarrheal diseases and health providers should give instructions to every mother or child minder on how to dispense ORS or electrolytes packets for appropriate dilution and use.

Quality improvement tools for chronic disease care--more effective processes are less likely to be implemented in developing countries.

PubMed

Hashim, Muhammad Jawad; Prinsloo, Adrianna; Mirza, Deen M

2013-01-01

Chronic disease services may be improved if care management processes (CMPs), such as disease-specific flowsheets and chronic disease registries, are used. The newly industrialized Gulf state health service has underdeveloped primary care but higher diabetes prevalence. This paper's aim is to investigate care management processes in United Arab Emirates (UAE) primary care clinics to explore these issues. A cross-sectional survey using self-administered questionnaires given to family physicians and nurses attending a UAE University workshop was used to collect data. All 38 participants completed the questionnaire: 68 per cent were women and 81 per cent physicians. Care management processes in use included: medical records, 76 per cent; clinical guidelines, 74 per cent; chronic disease care rooms, 74 per cent; disease-specific flowsheets, 61 per cent; medical record audits, 57 per cent; chronic disease nurse-educators, 58 per cent; electronic medical records (EMR), 34 per cent; and incentive plans based on clinical performance, 21 per cent. Only 62 per cent and 48 per cent reported that flowsheets and problem lists, respectively, were completed by physicians. Responses to the open-ended question included using traditional quality improvement (QI) approaches such as continuing education and staff meetings, but not proactive systems such as disease registries and self-management. The study used a small, non-random sample and the survey instrument's psychometric properties were not collected. Chronic disease care CMPs are present in UAE clinics but use is limited. Quality improvement should include disease registries, reminder-tracking systems, patient self-management support and quality incentives. This report highlights the lag regarding adopting more effective CMPs in developing countries.

Synthesis, spectroscopic and structural characterization of 5-benzoyl-4-phenyl-2-methylthio-1H-pyrimidine with theoretical calculations using density functional theory.

PubMed

Inkaya, Ersin; Dinçer, Muharrem; Sahan, Emine; Yıldırım, Ismail

2013-10-01

In this paper, we will report a combined experimental and theoretical investigation of the molecular structure and spectroscopic parameters (FT-IR, (1)H NMR, (13)C NMR) of 5-benzoyl-4-phenyl-2-methylthio-1H-pyrimidine. The compound crystallizes in the triclinic space group P-1 with Z=2. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d,p) and 6-311++G(d,p) basis sets in ground state and compared with the experimental data. All the assignments of the theoretical frequencies were performed by potential energy distributions using VEDA 4 program. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecules has been obtained by mapping electron density isosurface with electrostatic potential (ESP). Also, non-linear optical properties of the title compound were performed at B3LYP/6-311++G(d,p) level. The theoretical results showed an excellent agreement with the experimental values. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis, spectroscopic and structural characterization of 5-benzoyl-4-phenyl-2-methylthio-1H-pyrimidine with theoretical calculations using density functional theory

NASA Astrophysics Data System (ADS)

İnkaya, Ersin; Dinçer, Muharrem; Şahan, Emine; Yıldırım, İsmail

2013-10-01

In this paper, we will report a combined experimental and theoretical investigation of the molecular structure and spectroscopic parameters (FT-IR, 1H NMR, 13C NMR) of 5-benzoyl-4-phenyl-2-methylthio-1H-pyrimidine. The compound crystallizes in the triclinic space group P-1 with Z = 2. The molecular geometry was also optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d,p) and 6-311++G(d,p) basis sets in ground state and compared with the experimental data. All the assignments of the theoretical frequencies were performed by potential energy distributions using VEDA 4 program. Information about the size, shape, charge density distribution and site of chemical reactivity of the molecules has been obtained by mapping electron density isosurface with electrostatic potential (ESP). Also, non-linear optical properties of the title compound were performed at B3LYP/6-311++G(d,p) level. The theoretical results showed an excellent agreement with the experimental values.

Emergent constraint on equilibrium climate sensitivity from global temperature variability.

PubMed

Cox, Peter M; Huntingford, Chris; Williamson, Mark S

2018-01-17

Equilibrium climate sensitivity (ECS) remains one of the most important unknowns in climate change science. ECS is defined as the global mean warming that would occur if the atmospheric carbon dioxide (CO 2 ) concentration were instantly doubled and the climate were then brought to equilibrium with that new level of CO 2 . Despite its rather idealized definition, ECS has continuing relevance for international climate change agreements, which are often framed in terms of stabilization of global warming relative to the pre-industrial climate. However, the 'likely' range of ECS as stated by the Intergovernmental Panel on Climate Change (IPCC) has remained at 1.5-4.5 degrees Celsius for more than 25 years. The possibility of a value of ECS towards the upper end of this range reduces the feasibility of avoiding 2 degrees Celsius of global warming, as required by the Paris Agreement. Here we present a new emergent constraint on ECS that yields a central estimate of 2.8 degrees Celsius with 66 per cent confidence limits (equivalent to the IPCC 'likely' range) of 2.2-3.4 degrees Celsius. Our approach is to focus on the variability of temperature about long-term historical warming, rather than on the warming trend itself. We use an ensemble of climate models to define an emergent relationship between ECS and a theoretically informed metric of global temperature variability. This metric of variability can also be calculated from observational records of global warming, which enables tighter constraints to be placed on ECS, reducing the probability of ECS being less than 1.5 degrees Celsius to less than 3 per cent, and the probability of ECS exceeding 4.5 degrees Celsius to less than 1 per cent.

An Anterior-Posterior Gradient of Refractive Index in the Ameba and Its Significance in Ameboid Movement

PubMed Central

Allen, R. D.; Roslansky, J. D.

1958-01-01

Sustained locomotion in Amoeba proteus and Amoeba dubia results in the establishment of a measureable gradient of refractive index along the anterior-posterior axis of the cell, provided thickness of the specimens is kept constant by even compression under a selected coverglass supported by quartz beams of uniform diameter. The tail region of the ameba develops a higher refractive index, indicative of from 6 to 40 per cent more organic matter (expressed as protein) there than present in the front. This gradient fades on cessation of movement. The average protein concentrations in the crystal-free tails and fronts of 15 A. proteus were 3.9 and 3.4 per cent, respectively. In individual experiments, the tail-front difference ranged from one to eight times the accuracy of the method. Since the gradient of refractive index was shown not to result from extraction of water from the tail by the contractile vacuole, it was interpreted as displacement of water toward the anterior part of the cell during movement. It is suggested that contraction of the ectoplasm drives forward a "tide" of syncretic fluid, the anterior border of which is visible as the hyaline cap, which contains less than 1 per cent protein. The movement of the granular endoplasm into the hyaline cap would then complete the cycle by imbibition of the fluid tide. The theoretical positions of Pantin and of Dellinger have been combined in the proposal that ameba cytoplasm consists of a network of a contractile phase which is able to expel (by syneresis) a highly mobile fluid phase. Some other possible interpretations are discussed. PMID:13587543

An over-massive black hole in the compact lenticular galaxy NGC 1277.

PubMed

van den Bosch, Remco C E; Gebhardt, Karl; Gültekin, Kayhan; van de Ven, Glenn; van der Wel, Arjen; Walsh, Jonelle L

2012-11-29

Most massive galaxies have supermassive black holes at their centres, and the masses of the black holes are believed to correlate with properties of the host-galaxy bulge component. Several explanations have been proposed for the existence of these locally established empirical relationships, including the non-causal, statistical process of galaxy-galaxy merging, direct feedback between the black hole and its host galaxy, and galaxy-galaxy merging and the subsequent violent relaxation and dissipation. The empirical scaling relations are therefore important for distinguishing between various theoretical models of galaxy evolution, and they furthermore form the basis for all black-hole mass measurements at large distances. Observations have shown that the mass of the black hole is typically 0.1 per cent of the mass of the stellar bulge of the galaxy. Until now, the galaxy with the largest known fraction of its mass in its central black hole (11 per cent) was the small galaxy NGC 4486B. Here we report observations of the stellar kinematics of NGC 1277, which is a compact, lenticular galaxy with a mass of 1.2 × 10(11) solar masses. From the data, we determine that the mass of the central black hole is 1.7 × 10(10) solar masses, or 59 per cent of its bulge mass. We also show observations of five other compact galaxies that have properties similar to NGC 1277 and therefore may also contain over-massive black holes. It is not yet known if these galaxies represent a tail of a distribution, or if disk-dominated galaxies fail to follow the usual black-hole mass scaling relations.

Emergent constraint on equilibrium climate sensitivity from global temperature variability

NASA Astrophysics Data System (ADS)

Cox, Peter M.; Huntingford, Chris; Williamson, Mark S.

2018-01-01

Equilibrium climate sensitivity (ECS) remains one of the most important unknowns in climate change science. ECS is defined as the global mean warming that would occur if the atmospheric carbon dioxide (CO2) concentration were instantly doubled and the climate were then brought to equilibrium with that new level of CO2. Despite its rather idealized definition, ECS has continuing relevance for international climate change agreements, which are often framed in terms of stabilization of global warming relative to the pre-industrial climate. However, the ‘likely’ range of ECS as stated by the Intergovernmental Panel on Climate Change (IPCC) has remained at 1.5-4.5 degrees Celsius for more than 25 years. The possibility of a value of ECS towards the upper end of this range reduces the feasibility of avoiding 2 degrees Celsius of global warming, as required by the Paris Agreement. Here we present a new emergent constraint on ECS that yields a central estimate of 2.8 degrees Celsius with 66 per cent confidence limits (equivalent to the IPCC ‘likely’ range) of 2.2-3.4 degrees Celsius. Our approach is to focus on the variability of temperature about long-term historical warming, rather than on the warming trend itself. We use an ensemble of climate models to define an emergent relationship between ECS and a theoretically informed metric of global temperature variability. This metric of variability can also be calculated from observational records of global warming, which enables tighter constraints to be placed on ECS, reducing the probability of ECS being less than 1.5 degrees Celsius to less than 3 per cent, and the probability of ECS exceeding 4.5 degrees Celsius to less than 1 per cent.

[Reduction in the mortality from acute diarrheal diseases. The experiences of an action-research program].

PubMed

Gutiérrez, G; Guiscafré, H; Reyes, H; Pérez, R; Vega, R; Tomé, P

1994-01-01

In order to accelerate the descending mortality rate of acute diarrhea in children under five years of age in Mexico, six strategies were implemented. The results showed that after nine months, 49 per cent of mothers had been trained, and improved significantly their home management of diarrhea. The use of oral rehydration salts increased from 10 to 30 per cent; use of oral rehydration therapy increased from 77 to 83 per cent; and timely and appropriate demand for medical help increased from 51 to 62 per cent (p < 0.05). One hundred percent of all physicians received training, and they improved their therapeutic practices, as shown by a decrease in the use of antibiotics from 48 to 34 per cent; prescription of restrictive diets diminished from 33 to 4 per cent; and oral rehydration therapy increased from 74 to 87 per cent. Thirty-four verbal autopsies were carried out, and they showed that 70 per cent of the children who died did so in their homes or in their way to the hospital, despite the fact that 94 per cent of them had received medical care previous to their death, and that 84 per cent of these had been seen by a doctor within 24 hours previous to their death. In 85 per cent of these cases, the physician involved was a private physician of rural or marginal areas. Monthly analysis of death certificates showed that, during the first year of the program (1991), deaths due to diarrhea diminished 20 per cent, while the corresponding figure for 1992 was 52 per cent. In conclusion, the combination of strategies followed in the program made it possible to accelerate, on a short-term basis, the descending trend of deaths due to diarrhea. It was also shown that an intervention project such as the one presented here may efficiently link results from research to decisions taken by policy-makers, and that these can be effectively turned into actions.

Systematic review of recent evidence for the safety and efficacy of elective endovascular repair in the management of infrarenal abdominal aortic aneurysm.

PubMed

Drury, D; Michaels, J A; Jones, L; Ayiku, L

2005-08-01

Conventional management of abdominal aortic aneurysm (AAA) is by open repair and is associated with a mortality rate of 2-6 per cent. Endovascular aneurysm repair (EVAR) is an alternative technique first introduced in 1991. A systematic review was undertaken of the evidence for the safety and efficacy of elective EVAR in the management of asymptomatic infrarenal AAA. Thirteen electronic bibliographical databases were searched, covering biomedical, health-related, science and social science literature. Outcomes were assessed with respect to efficacy (successful deployment, technical success, conversion rates and secondary intervention rates) and safety (30-day mortality rate, procedure morbidity rates and technical issues-endoleaks, graft thrombosis, stenosis and migration). Of 606 reports identified, 61 met the inclusion criteria (three randomized and 15 non-randomized controlled trials, and 43 uncontrolled studies). There were 29 059 participants in total; 19,804 underwent EVAR. Deployment was successful in 97.6 per cent of cases. Technical success (complete aneurysm exclusion) was 81.9 per cent at discharge and 88.8 per cent at 30 days. Secondary intervention to treat endoleak or maintain graft patency was required in 16.2 per cent of patients. Mean stay in the intensive care unit and mean hospital stay were significantly shorter following EVAR. The 30-day mortality rate for EVAR was 1.6 per cent (randomized controlled trials) and 2.0 per cent in nonrandomized trials and case series. Technical complications comprised stent migration (4.0 per cent), graft limb thrombosis (3.9 per cent), endoleak (type I, 6.8 per cent; type II, 10.3 per cent; type III, 4.2 per cent) and access artery injury (4.8 per cent). EVAR is technically effective and safe, with lower short-term morbidity and mortality rates than open surgery. However, there is a need for extended follow-up as the long-term success of EVAR in preventing aneurysm-related deaths is not yet known.

Food insecurity and low income in an English inner city.

PubMed

Tingay, Richard S; Tan, Chuan Jin; Tan, Neil C W; Tang, Stephen; Teoh, Pei Fen; Wong, Rebecca; Gulliford, Martin C

2003-06-01

Low incomes may not provide the minimum requirements for healthy living. We evaluated experiences of food insecurity in relation to income in inner London. Subjects attending 10 general medical practices completed a short self-administered questionnaire, including the short form Household Food Security Scale and a short food frequency questionnaire. Responses were obtained from 431/495 (87 per cent) subjects. Overall 87 (20 per cent) of subjects were classified as food insecure. Food insecurity was negatively associated with household income (p = 0.004). University-educated subjects (8 per cent) were less often food insecure than all others (26 per cent). Subjects who were food insecure were less likely to report eating fruit daily (food secure 48 per cent, food insecure 33 per cent, p = 0.017) or vegetables or salads daily (food secure 56 per cent, food insecure 34 per cent, p = 0.002). Experiences of food insecurity may be common in households with incomes at the level of the UK national minimum wage or lower.

The Cleveland Clinic experience with adrenal cortical carcinoma.

PubMed

Bodie, B; Novick, A C; Pontes, J E; Straffon, R A; Montie, J E; Babiak, T; Sheeler, L; Schumacher, P

1989-02-01

Between 1936 and 1987, 82 patients with adrenal cortical carcinoma were seen at our clinic. Of these patients 49 (72 per cent) have been seen during the last 25 years. A total of 40 patients (48.8 per cent) presented with a hormonally functional tumor and 42 (51.2 per cent) had a nonfunctional tumor. Forty patients (48.8 per cent) presented with localized disease, 12 (14.6 per cent) with regional disease and 30 (36.6 per cent) with distant metastases. Complete surgical removal of all gross tumor was achieved in 49 patients. Over-all 3 and 5-year patient survival rates in this series were 37.5 and 25.1 per cent, respectively. Survival was significantly improved (43.9 per cent at 5 years, p equals 0.0001) in patients with localized disease that was completely removed surgically; postoperative adjuvant therapy with op'-DDD was of no benefit in these patients. Survival in patients with metastatic disease was poor and was not improved by treatment with op'-DDD, cytotoxic chemotherapy or radiation therapy.

Semi-supervised learning for photometric supernova classification

NASA Astrophysics Data System (ADS)

Richards, Joseph W.; Homrighausen, Darren; Freeman, Peter E.; Schafer, Chad M.; Poznanski, Dovi

2012-01-01

We present a semi-supervised method for photometric supernova typing. Our approach is to first use the non-linear dimension reduction technique diffusion map to detect structure in a data base of supernova light curves and subsequently employ random forest classification on a spectroscopically confirmed training set to learn a model that can predict the type of each newly observed supernova. We demonstrate that this is an effective method for supernova typing. As supernova numbers increase, our semi-supervised method efficiently utilizes this information to improve classification, a property not enjoyed by template-based methods. Applied to supernova data simulated by Kessler et al. to mimic those of the Dark Energy Survey, our methods achieve (cross-validated) 95 per cent Type Ia purity and 87 per cent Type Ia efficiency on the spectroscopic sample, but only 50 per cent Type Ia purity and 50 per cent efficiency on the photometric sample due to their spectroscopic follow-up strategy. To improve the performance on the photometric sample, we search for better spectroscopic follow-up procedures by studying the sensitivity of our machine-learned supernova classification on the specific strategy used to obtain training sets. With a fixed amount of spectroscopic follow-up time, we find that, despite collecting data on a smaller number of supernovae, deeper magnitude-limited spectroscopic surveys are better for producing training sets. For supernova Ia (II-P) typing, we obtain a 44 per cent (1 per cent) increase in purity to 72 per cent (87 per cent) and 30 per cent (162 per cent) increase in efficiency to 65 per cent (84 per cent) of the sample using a 25th (24.5th) magnitude-limited survey instead of the shallower spectroscopic sample used in the original simulations. When redshift information is available, we incorporate it into our analysis using a novel method of altering the diffusion map representation of the supernovae. Incorporating host redshifts leads to a 5 per cent improvement in Type Ia purity and 13 per cent improvement in Type Ia efficiency. A web service for the supernova classification method used in this paper can be found at .

Prevalence of refractive errors among schoolchildren in rural central Ethiopia.

PubMed

Mehari, Zelalem Addisu; Yimer, Abdirahman Wollie

2013-01-01

The aim of the present study was to assess the prevalence of refractive errors and visual impairment among schoolchildren in rural central Ethiopia. A cross-sectional study was conducted from November 2010 to January 2011 among 5,470 schoolchildren from 14 schools, of whom 4,238 (aged 7-18 years) were screened for refractive errors. In all participants, uncorrected vision and best corrected visual acuity were determined and those with a visual acuity of 6/12 or worse, underwent a complete ophthalmic examination to determine the cause of visual impairment. Myopia was defined as a spherical equivalent of -0.50 dioptre (D) or greater in one or both eyes and hyperopia as a spherical equivalent of +2.00 D or greater. A cylindrical power of -0.50 DC (D cylinder) or greater was considered as astigmatism. Chi-square was used to test differences in proportions. Differences were considered to be statistically significant at the five per cent level. Of the 4,238 children, 405 (9.5 per cent) were visually impaired and of these 267 children were diagnosed as having refractive errors, with an overall prevalence of 6.3 per cent, comprised of 6.1 per cent in boys and 6.6 per cent in girls. Myopia is the most prevalent refractive error; accounting for 6.0 per cent, followed by compound myopic astigmatism 1.2 per cent, then simple myopic astigmatism 0.5 per cent, mixed astigmatism 0.26 per cent and finally hyperopia 0.33 per cent. Reasons for visual acuity of 6/12 or worse in the better eye were found to be refractive error (65.9 per cent), corneal problems (12.8 per cent) and amblyopia (9.6 per cent). The prevalence of manifest strabismus in the study group was 1.1 per cent (n = 45). The study concluded that uncorrected refractive error is a common cause of visual impairment among schoolchildren in rural central Ethiopia. This indicates the need for regular school-screening programs that provide glasses at low cost or free of charge for those who have refractive errors. © 2012 The Authors; Clinical and Experimental Optometry © 2012 Optometrists Association Australia.

Declines in tobacco brand recognition and ever-smoking rates among young children following restrictions on tobacco advertisements in Hong Kong.

PubMed

Fielding, R; Chee, Y Y; Choi, K M; Chu, T K; Kato, K; Lam, S K; Sin, K L; Tang, K T; Wong, H M; Wong, K M

2004-03-01

We compared the recognition of tobacco brands and ever-smoking rates in young children before (1991) and after (2001) the implementation of cigarette advertising restrictions in Hong Kong and identified continuing sources of tobacco promotion exposure. A cross-sectional survey of 824 primary school children aged from 8 to 11 (Primary classes 3-4) living in two Hong Kong districts was carried out using self-completed questionnaires examining smoking behaviour and recognition of names and logos from 18 tobacco, food, drink and other brands common in Hong Kong. Ever-smoking prevalence in 2001 was 3.8 per cent (1991, 7.8 per cent). Tobacco brand recognition rates ranged from 5.3 per cent (Viceroy name) to 72.8 per cent (Viceroy logo). Compared with 1991, in 2001 never-smoker children recognized fewer tobacco brand names and logos: Marlboro logo recognition rate fell by 55.3 per cent. Similar declines were also seen in ever-smoker children, with recognition of the Marlboro logo decreasing 48 per cent. Recognition rates declined amongst both boys and girls. Children from non-smoking families constituted 51 per cent (426) of the sample, whereas 34.5 per cent (284), 8.5 per cent (70), 1.7 per cent (14) and 4.4 per cent (36) of the children had one, two, three or more than three smoking family members at home, respectively. Tobacco brand recognition rates and ever-smoking prevalence were significantly higher among children with smoking family members compared with those without. Among 12 possible sources of exposure to cigarette brand names and logos, retail stalls (75.5 per cent; 622), indirect advertisements (71.5 per cent; 589) and magazines (65.3 per cent; 538) were ranked the most common. Advertising restrictions in Hong Kong have effectively decreased primary-age children's recognition of tobacco branding. However, these children remain vulnerable to branding, mostly through exposure from family smokers, point-of-sale tobacco advertisement and occasional promotions. Action to curb these is now required.

Acid reflux management: ENT perspective.

PubMed

Ahmad, Ijaz; Batch, A J G

2004-01-01

Otolaryngological manifestations of acid reflux include a wide range of pharyngeal and laryngeal symptoms; and the constellation of symptoms has been called laryngopharyngeal reflux. This is a prospective study in a cohort of patients with various throat symptoms suggestive of laryngopharyngeal reflux (LPR) who underwent flexible oesophago-gastroscopy, as a principal investigation. The aims were to look at the most reliable symptom(s) and sign(s), the diagnostic role of flexible oesophago-gastroscopy and the treatment response in these patients. The endoscopy score of 0 to 3 was based on endoscopic findings and the treatment response was measured from 0 to 100 per cent improvement of symptoms, as described by the patients. There were a total of 303 patients, 174 females and 129 males with ages ranging from 19 to 88 years. Seventy-five per cent had had symptoms for more than a year. Fifteen per cent were smokers. Globus, voice change, sore throat, dysphagia and cough were the predominant symptoms. Most patients, however, presented with a complex of various other secondary symptoms. The endoscopic findings were abnormal in 98 per cent of patients. Apart from the finding of non-specific hyperaemia, usually of the posterior larynx (13 per cent), lesions of the larynx and vocal folds were surprisingly uncommon. Proton pump inhibitors (PPI) were prescribed in 90 per cent of patients. A total of 233 (76.8 per cent) responded to treatment. The improvement of symptoms ranged from 25 per cent in 36 (23 per cent), 50 per cent in 60 (20 per cent), 75 per cent in 59 (19 per cent) and 100 per cent in 78 (26 per cent) patients. Accumulative analysis of variance showed a significant difference between treatment responders and non-responders (p <0.04). In a logistic regression model patients with globus, voice change and gastric prolapse were more likely to respond to treatment (p <0.04). It can be concluded that voice change, sore throat, globus and cough choking are the most reliable symptoms of laryngopharyngeal reflux. Voice change and globus symptoms can be of predictive value in terms of successful treatment response. Flexible oesophago-gastroscopy (FOG) is a simple, safe and reliable way of assessment in these cases and treatment with PPI can be effective in the majority of patients.

Stress remagnetization in pyrrhotite-calcite synthetic aggregates

NASA Astrophysics Data System (ADS)

Robion, Philippe; Borradaile, Graham J.

2001-01-01

Stress-induced remagnetization has been applied to multidomain pyrrhotite-calcite synthetic aggregates in a triaxial rig. Experimental deformation used 150MPa confining pressure, a constant strain rate of 10-5 s-1 and applied differential stresses of up to 70MPa. New components of magnetization, parallel to the direction of the pressure vessel field, were added to the pre-deformational magnetization. The intensity of remagnetization (M'-M0) increases with the intensity of the applied differential stress and affects the coercivity fraction below 15mT. Bulk shortening is less than 8 per cent, thus grain rotation cannot explain selective remagnetization of the low-coercivity fraction. Remagnetization is thus attributed to deformational viscous remanent magnetization (DVRM). It is observed that high-coercivity (>15mT) grains do not remagnetize. There is, however, slight progressive rotation of pre-deformational magnetization with increasing strain up to 8 per cent of bulk shortening. The lack of piezoremanent magnetization in the high-coercivity range may be due to defects introduced in pyrrhotite during sample preparation. Experiments using synthetic pyrrhotite, expected to show low dislocation densities, would be necessary to test this effect.

A radio characterization of Galactic compact bubbles

NASA Astrophysics Data System (ADS)

Ingallinera, A.; Trigilio, C.; Umana, G.; Leto, P.; Noriega-Crespo, A.; Flagey, N.; Paladini, R.; Agliozzo, C.; Buemi, C. S.

2014-02-01

We report the radio observations of a subsample of the 428 Galactic compact bubbles discovered at 24 μm with the MIPSGAL survey. Pervasive through the entire Galactic plane, these objects are thought to be different kinds of evolved stars. The very large majority of the bubbles (˜70 per cent) are however not yet classified. We conducted radio observations with the Expanded Very Large Array at 6 and 20 cm in order to obtain the spectral index of 55 bubbles. We found that at least 70 per cent of the 31 bubbles for which we were effectively able to compute the spectral index (or its lower limit) are likely to be thermal emitters. We were also able to resolve some bubbles, obtaining that the size of the radio nebula is usually similar to the IR size, although our low resolution (with respect to IR images) did not allow further morphological studies. Comparisons between radio flux densities and IR archive data from Spitzer and IRAS suggest that at least three unclassified bubbles can be treated as planetary nebula candidates.

A substantial amount of hidden magnetic energy in the quiet Sun.

PubMed

Bueno, J Trujillo; Shchukina, N; Ramos, A Asensio

2004-07-15

Deciphering and understanding the small-scale magnetic activity of the quiet solar photosphere should help to solve many of the key problems of solar and stellar physics, such as the magnetic coupling to the outer atmosphere and the coronal heating. At present, we can see only approximately 1 per cent of the complex magnetism of the quiet Sun, which highlights the need to develop a reliable way to investigate the remaining 99 per cent. Here we report three-dimensional radiative transfer modelling of scattering polarization in atomic and molecular lines that indicates the presence of hidden, mixed-polarity fields on subresolution scales. Combining this modelling with recent observational data, we find a ubiquitous tangled magnetic field with an average strength of approximately 130 G, which is much stronger in the intergranular regions of solar surface convection than in the granular regions. So the average magnetic energy density in the quiet solar photosphere is at least two orders of magnitude greater than that derived from simplistic one-dimensional investigations, and sufficient to balance radiative energy losses from the solar chromosphere.

Vector dark energy and high-z massive clusters

NASA Astrophysics Data System (ADS)

Carlesi, Edoardo; Knebe, Alexander; Yepes, Gustavo; Gottlöber, Stefan; Jiménez, Jose Beltrán.; Maroto, Antonio L.

2011-12-01

The detection of extremely massive clusters at z > 1 such as SPT-CL J0546-5345, SPT-CL J2106-5844 and XMMU J2235.3-2557 has been considered by some authors as a challenge to the standard Λ cold dark matter cosmology. In fact, assuming Gaussian initial conditions, the theoretical expectation of detecting such objects is as low as ≤1 per cent. In this paper we discuss the probability of the existence of such objects in the light of the vector dark energy paradigm, showing by means of a series of N-body simulations that chances of detection are substantially enhanced in this non-standard framework.

One year study of bacterial and fungal nosocomial infections among patients in pediatric intensive care unit (PICU) in Alexandria.

PubMed

El-Nawawy, Ahmed Ahmed; Abd El-Fattah, Mohamed Mohamed; Metwally, Hala Abd El-Raouf; Barakat, Shahira Salah El Din; Hassan, Ihab Abdel Rehim

2006-06-01

A 1-year prospective and observational study included all admissions (n=216) until 48 h after discharge to Alexandria PICU between first of May 2003 and end of April 2004. Cultures for bacteria and fungi and antibiotic sensitivity tests (19 antibiotic using Bauer-Kirby disc diffusion method) were obtained (blood, stool, urine and cerebrospinal fluid, if needed) and repeated on suspicion of NIs. All cannulae, endotracheal tube (ET) aspirates and tips, nasogastric tubes and different catheters were cultured. All PICU health care workers (HCWs) were subjected to throat and under-finger nails cultures as well as inanimate objects, both on bimonthly basis. The referral place (ward or emergency), PRISM III score, length of stay (LOS) and fate were recorded. Amongst those patients whose age ranged from 1 to 23 months, 23 per cent had NIs with infection rates of 40/1000 days. Significantly high rates of mortality, LOS and PRISM III score were encountered among patients with NIs (52 per cent vs 30 per cent; 9.4+/-4.8 vs 5.4+/-2.2 days; 14.4+/-7 vs 11.8+/-6 respectively). The descending order of frequency of NIs was blood stream infection (BSI) (47 per cent), urinary tract infection (UTI) (28 per cent), ventilator-associated pneumonia (VAP) (16 per cent) and meningitis (9 per cent). Gr-ve bacilli accounted for 76.7 per cent; Gr+ve cocci 13.3 per cent (with satisfactory sensitivity to cefepime, imipenem and meropenem) and Candida albicans 10 per cent of all NIs. The rate of NIs/1000 device days were: 18.7 per cent for BSI, 10.9 per cent for VAP and 25.5 per cent for UTI. Vulnerable age groups were >6 m for VAP and <6 m for meningitis. Multiple logistic regression analysis identified LOS, PRISM III score and referral from wards a predictors of NI acquisition (odd ratio and 95 per cent confidence interval: 1.537, 1.423-1.659; 1.073, 1.041-1.105 and 0.269, 0.178-0.406 respectively). Bimonthly cultures for HCWs isolated coagulase-ve Staphylococci, while inanimate objects isolated diphtheroids and Candida albicans. NIs rate was high (23 per cent) mainly due to severity of condition on admission as shown by high PRISM III score value, the high PRISM III score, LOS and referral from wards were predictors of acquisition of NIs and there is a high incidence of Candida albicans infection (10 per cent of NIs).

Effect of preoperative biliary drainage on bacterial flora in bile of patients with periampullary cancer.

PubMed

Scheufele, F; Aichinger, L; Jäger, C; Demir, I E; Schorn, S; Sargut, M; Erkan, M; Kleeff, J; Friess, H; Ceyhan, G O

2017-01-01

Patients with obstructive jaundice due to periampullary tumours may undergo preoperative biliary drainage (PBD). The effect of PBD on the microbiome of the biliary system and on postoperative outcome remains unclear. A single-centre retrospective study of patients with obstructive jaundice due to periampullary cancer, treated between July 2007 and July 2015, was undertaken. Intraoperative bile samples were obtained for microbiological analysis after transection of the common bile duct. Postoperative complications were registered. Of 290 patients treated, intraoperative bile samples were present for 172 patients (59·3 per cent) who had PBD and 118 (40·7 per cent) who did not. Contamination of bile was increased significantly in patients who underwent stenting (97·1 per cent versus 18·6 per cent in those without stenting; P < 0·001). PBD resulted in a shift in the biliary microbiome from Escherichia coli in non-stented patients (45 per cent versus 19·2 per cent in stented patients; P = 0·009) towards increased contamination with Enterococcus faecalis (9 versus 37·7 per cent respectively; P = 0·008) and Enterobacter cloacae (0 versus 20·4 per cent; P = 0·033). This shift was associated with a high incidence of bacterial resistance against ampicillin-sulbactam (63·6 per cent versus 18 per cent in patients with no PBD; P < 0·001), piperacillin-tazobactam (30·1 versus 0 per cent respectively; P = 0·003), ciprofloxacin (28·5 versus 5 per cent; P = 0·047) and imipenem (26·6 versus 0 per cent; P = 0·011). The rate of wound infection was higher in patients with a positive bile culture (21·0 per cent versus 6 per cent in patients with sterile bile; P = 0·002). Regression analysis revealed the presence of Enterococcus faecium (odds ratio 2·83, 95 per cent c.i. 1·17 to 6·84; P = 0·021) and Citrobacter species (odds ratio 5·09, 1·65 to 15·71; P = 0·005) as independent risk factors for postoperative wound infection. There are fundamental differences in the biliary microbiome of patients with periampullary cancer who undergo PBD and those who do not. PBD induces a shift of the biliary microbiome towards a more aggressive and resistant spectrum, which requires a differentiated perioperative antibiotic treatment strategy. © 2017 BJS Society Ltd Published by John Wiley & Sons Ltd.

A serosurvey for selected pathogens in Greek European wild boar

PubMed Central

Touloudi, A.; Valiakos, G.; Athanasiou, L. V.; Birtsas, P.; Giannakopoulos, A.; Papaspyropoulos, K.; Kalaitzis, C.; Sokos, C.; Tsokana, C. N.; Spyrou, V.; Petrovska, L.; Billinis, C.

2015-01-01

Objectives Serum samples, collected from 94 European wild boar (Sus scrofa) during the hunting seasons 2006 -2010 from different regions of Greece, were examined in order to estimate the role of these wildlife species as reservoir of pathogens important for livestock and/or public health. Materials and Methods The assays used for this purpose were commercial indirect ELISA for the detection of antibodies against porcine circovirus type 2 (PCV-2), porcine reproductive and respiratory syndrome (virus) (PRRSV), Aujeszky's disease virus (ADV), influenza A (IA) virus, Actinobacillus pleuropneumoniae, Mycoplasma hyopneumoniae, Salmonella species, Trichinella species and indirect immunofluorescence antibody test for the detection of antibodies against Toxoplasma gondii and Neospora caninum. Results Antibodies against PCV-2, PRRSV, ADV, IA virus,A. pleuropneumoniae, M. hyopneumoniae,Salmonella species, Trichinella species, T. gondii and N. caninum were detected in 19.1 per cent, 12.8 per cent, 35.1 per cent, 1.1 per cent, 57.4 per cent, 0 per cent, 4.3 per cent, 6.4 per cent, 5.2 per cent and 1.1 per cent of the samples, respectively. Cluster analysis revealed a hot spot of seropositivity near Bulgarian border; seropositivity to ADV was more common among female animals. Conclusions These results indicate exposure of wild boar to most of the above-mentioned pathogens, raising concern about the possibility that these species may pose a significant health risk for livestock and/or humans. PMID:26392908

Pathogen profile of clinical mastitis in Irish milk-recording herds reveals a complex aetiology.

PubMed

Keane, O M; Budd, K E; Flynn, J; McCoy, F

2013-07-06

Effective mastitis control requires knowledge of the predominant pathogen challenges on the farm. In order to quantify this challenge, the aetiological agents associated with clinical mastitis in 30 milk-recording dairy herds in Ireland over a complete lactation were investigated. Standard bacteriology was performed on 630 pretreatment quarter milk samples, of which 56 per cent were culture-positive, 42 per cent culture-negative and 2 per cent contaminated. Two micro-organisms were isolated from almost 5 per cent of the culture-positive samples. The bacteria isolated were Staphylococcus aureus (23 per cent), Streptococcus uberis (17 per cent), Escherichia coli (9 per cent), Streptococcus species (6 per cent), coagulase-negative Staphylococci (4 per cent) and other species (1 per cent). A wide variety of bacterial species were associated with clinical mastitis, with S aureus the most prevalent pathogen overall, followed by S uberis. However, the bacterial challenges varied widely from farm to farm. In comparison with previous reports, in the present study, the contagious pathogens S aureus and Streptococcus agalactiae were less commonly associated with clinical mastitis, whereas, the environmental pathogens S uberis and E coli were found more commonly associated with clinical mastitis. While S aureus remains the pathogen most commonly associated with intramammary infection in these herds, environmental pathogens, such as S uberis and E coli also present a considerable challenge.

Prevalence of enteropathic Escherichia coli in dogs with acute and chronic diarrhoea.

PubMed

Sancak, A A; Rutgers, H C; Hart, C A; Batt, R M

2004-01-24

Samples of faeces from 57 dogs with acute diarrhoea, 82 dogs with chronic diarrhoea, 34 clinically healthy household dogs and 88 kennelled control dogs were analysed by hybridisation, using DNA probes to detect enteropathogenic Escherichia coli (EPEC) and enterotoxigenic E coli (ETEC), verocytotoxin-producing E coli (VTEC), enterohaemorrhagic E coli (EHEC), enteroinvasive E coli (EIEC) and enteroaggregative E coli (EAggEC). Samples of duodenal juice from 60 of the 82 dogs with chronic diarrhoea were also examined. Significantly more of the dogs with diarrhoea were excreting EPEC (acute 35.1 per cent, chronic 31.7 per cent) and VTEC (acute 24.6 per cent, chronic 28 per cent) than the kennelled dogs (EPEC 17.1 per cent, VTEC 0 per cent) or the household control dogs (EPEC 6 per cent, VTEC 5.9 per cent). Enteropathic E coli was also detected in the duodenal juice of 23 of 60 (38.3 per cent) of the dogs with chronic diarrhoea. The EPEC attaching and effacing A (eaeA) gene and the verocytotoxin 1 (VR1) gene coding for VTEC were often found together. There was good agreement between in vitro studies and hybridisation for the detection of eaeA and VT1. Isolates from the dogs with diarrhoea adhered significantly more to Hep-2 cells, and VT1-positive strains from the dogs with diarrhoea consistently killed more than 50 per cent of Vero cells.

Thirteen-week dose-intensifying simultaneous combination chemotherapy protocol for malignant lymphoma in dogs.

PubMed

Zenker, I; Meichner, K; Steinle, K; Kessler, M; Hirschberger, J

2010-11-06

This prospective study aimed to record the toxicity profile of a dose-intensifying simultaneous chemotherapy (DISC) protocol for lymphoma in dogs. Remission rates and the duration of the protocol were also evaluated. Twenty-one dogs were studied. Diagnosis was based on cytological or histological assessments. The DISC protocol is a 13-week maintenance-free protocol. L-Asparaginase (400 iu/kg) was administered subcutaneously on day 1, followed by weekly simultaneous intravenous administration of vincristine (0.7 mg/m(2) = 100 per cent), cyclophosphamide (200 mg/m(2) = 100 per cent) and doxorubicin (30 mg/m(2) = 100 per cent) at a starting dose level of 33 per cent. Dose levels were given twice and then increased by 5 to 7 per cent if grade 0 or I toxicities were seen, to a maximum dose level of 60 per cent. Two dogs experienced a grade IV toxicity (asymptomatic neutropenia in one dog and sepsis in the other). Two episodes of asymptomatic grade III thrombocytopenia and one episode of neutropenia were recorded. Other toxic events were infrequent and mild. Only one dog required hospitalisation for less than 72 hours. Seventeen dogs (80.9 per cent) achieved complete remission, one (4.8 per cent) achieved partial remission, two (9.5 per cent) had stable disease and in one (4.8 per cent) disease progressed.

Sexual and marital relationships after radiotherapy for seminoma

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

Schover, L.R.; Gonzales, M.; von Eschenbach, A.C.

Questionnaires on sexual function, marital status, and fertility were returned by 84 men who received radiotherapy for seminoma (Stage I, II, or III). The mean length of follow-up was ten years. Although 93 per cent were married, 19 per cent had low rates of sexual activity, 12 per cent reported low sexual desire, 15 per cent had erectile dysfunction, 10 per cent had difficulty reaching orgasm, and 14 per cent had premature ejaculation. The most common problems were reduced intensity of orgasm (33%) and reduced semen volume (49%). Twenty-one men remained childless, and 30 per cent of men worried atmore » least occasionally about infertility. Thirteen children were conceived after cancer therapy. The data suggest that sexual dysfunction and infertility are important concerns for a subgroup of men treated for seminoma.« less

Exploring the safety measures by doctors on after-hours house call services.

PubMed

Ifediora, Chris

2015-01-01

Aggression against doctors involved in after-hours house calls (AHHC) is widely perceived to be high. It is, however, unclear how doctors who perform this service manage the risk of aggressive patients during home visits. The aim of this paper is to explore if and how doctors manage the risk of violence against them during AHHC. A survey was designed and administered to all 300 Australian-based doctors engaged in AHHC under the National Home Doctor Service (NHDS). The survey was conducted from September 2014 to November 2014. There were 172 responses (57.3 per cent). Only 43 per cent of respondents adopted personal protective measures. The remaining 57 per cent had none; of those 6 per cent had never considered protective measures, and 31.8 per cent were aware of the risk of violence, but were unsure of what to do. Measures adopted include the use of chaperones/security personnel (34.1 per cent), dependence on surgery policies (31.2 per cent), de-escalation techniques (15.2 per cent), panic buttons (7.2 per cent), personal alarms (6.1 per cent), and others (6.5 per cent). Females were more likely to adopt personal protective measures than males (OR 4.94; p<0.01; CI 1.70-14.34), and Australian-trained doctors were less likely to do so relative to overseas-trained doctors (OR 0.35; p=0.04; CI 0.12-0.99). Just over half of the doctors involved in AHHC took no precautions against aggressive attacks while on duty, and nearly one-third relied on the policies of their employing surgeries.

A comparative study on accuracy of liquid crystal forehead, digital electronic axillary, infrared tympanic with glass-mercury rectal thermometer in infants and young children.

PubMed

Kongpanichkul, A; Bunjongpak, S

2000-09-01

This study was carried out to assess the accuracy of three devices namely, liquid crystal forehead, digital electronic axillary and infrared tympanic thermometer, using a glass-mercury rectal thermometer as the control. The subjects were two hundred children aged 0-48 months. The mean rectal temperature was 38.0 +/- 0.91 degrees C; forehead, 37.83 +/- 0.94 degrees C; tympanic, 37.77 +/- 0.95 degrees C, and axillary, 37.71 +/- 0.86 degrees C. Compared to the rectal temperature, all values were significantly lower (p < 0.05). Forehead, tympanic and axillary temperature differed from rectal temperature by at least 0.5 degrees C in 33.33 per cent, 23.5 per cent and 31.5 per cent of subjects, and at least 1 degrees C in 22 per cent, 1 per cent and 6 per cent of subjects respectively. Accuracy in detection of fever was 79 per cent for forehead, 85.5 per cent for tympanic and 84 per cent for axillary thermometry. Sensitivity of the three devices was 67-83 per cent in detection of fever and 64-77 per cent in detection of high fever. Tympanic thermometry had the best performance while forehead thermometry had the poorest. After using revised diagnostic threshold temperature by ROC curves, sensitivity of each device improved but accuracy was nearly the same. It is concluded that the three devices are not suitable as a substitute for a glass-mercury rectal thermometer in assessment of fever in infants and young children.

Geometric characterization and simulation of planar layered elastomeric fibrous biomaterials

PubMed Central

Carleton, James B.; D'Amore, Antonio; Feaver, Kristen R.; Rodin, Gregory J.; Sacks, Michael S.

2014-01-01

Many important biomaterials are composed of multiple layers of networked fibers. While there is a growing interest in modeling and simulation of the mechanical response of these biomaterials, a theoretical foundation for such simulations has yet to be firmly established. Moreover, correctly identifying and matching key geometric features is a critically important first step for performing reliable mechanical simulations. The present work addresses these issues in two ways. First, using methods of geometric probability we develop theoretical estimates for the mean linear and areal fiber intersection densities for two-dimensional fibrous networks. These densities are expressed in terms of the fiber density and the orientation distribution function, both of which are relatively easy-to-measure properties. Secondly, we develop a random walk algorithm for geometric simulation of two-dimensional fibrous networks which can accurately reproduce the prescribed fiber density and orientation distribution function. Furthermore, the linear and areal fiber intersection densities obtained with the algorithm are in agreement with the theoretical estimates. Both theoretical and computational results are compared with those obtained by post-processing of SEM images of actual scaffolds. These comparisons reveal difficulties inherent to resolving fine details of multilayered fibrous networks. The methods provided herein can provide a rational means to define and generate key geometric features from experimentally measured or prescribed scaffold structural data. PMID:25311685

Support needs of veterinary surgeons during the first few years of practice: perceptions of recent graduates and senior partners.

PubMed

Routly, J E; Taylor, I R; Turner, R; McKernan, E J; Dobson, H

2002-02-09

Postal surveys or personal interviews of 76 recent veterinary graduates and their 49 employers were undertaken to establish their perceptions of good practice when integrating a new graduate into a business and their preferred methods of assessment and development. Practice type and location were the main influences on graduates looking for their first job. Interviews were mostly informal. Employers expected basic veterinary competence and candidates expected good quality support. Most graduates (93 per cent) had their own consultations on the first day. During early consultations 2 per cent of senior vets accompanied the new graduate, 95 per cent of practices provided senior back-up either in person or by telephone but in 3 per cent no back-up was available. Most new graduates (90 per cent) were satisfied with their workload. Three-fifths were on-call within the first week, and 95 per cent within a month. Graduates received calls directly in 45 per cent of practices, in 9 per cent seniors screened the calls, and the remainder used a third party. Assistance from experienced lay staff varied greatly. Discussion of problems was mainly informal. There was little spontaneous feedback and problems resulted from inadequate communication. One in three new graduates left their first job within two years, and one in six identified lack of support, heavy workload, stress or clashes with staff as a primary reason. This high turnover was a problem for employers. From the new graduates' perspectives, initial problems included: being on call (59 per cent), financial aspects (47 per cent) and surgery (43 per cent). Communicating with clients and learning to prioritise jobs were also difficult. New graduates took longer over procedures (79 per cent of employers commented) and required extra back-up (91 per cent) both of which reduced income (59 per cent). Nearly all the seniors felt that their current new graduates had coped 'quite well', although it was claimed that new graduates lacked the ability to talk to clients at the appropriate level, wanted to bring all their scientific knowledge to bear on every case, and often failed to consider the obvious or to appreciate clients' needs. Only 18 per cent of practices had formal and regular review procedures but all monitored the response of clients and watched the new graduate perform. Feedback to their new colleague was considered 'adequate' by 85 per cent of seniors, although 45 per cent of graduates felt they had not received enough. Eighty-three per cent of new graduates felt 'moderately prepared' by their undergraduate course, and 76 per cent of senior vets were 'generally satisfied' Both wanted improvements in extramural studies and increased exposure to routine cases. Senior partners sought greater commitment in the undergraduate curriculum to financial/legal issues and communication skills. Over a third of employers (38 per cent) had a 'great influence' on the choice of continuing professional development courses for their recent graduates. New graduates chose courses to deal with a perceived weakness, or to specialise, and welcomed opportunities to meet other new graduates and share early experiences. It was concluded that turnover and staff problems would be reduced if practices became more effective in coping with new arrivals, especially by supporting their development.

Progression of aortic stenosis in the boxer.

PubMed

French, A; Luis Fuentes, V; Dukes-McEwan, J; Darke, P G; Martin, M; Corcoran, B

2000-10-01

Thirty-five boxers that had been referred to the Royal (Dick) School of Veterinary Studies between 1989 and 1994 with left heart base murmurs and aortic velocities greater than 1.5 m/second on Doppler echocardiography were recalled for clinical examination and Doppler echocardiography between 1995 and 1996. Five dogs (14 per cent) showed an increase in murmur grade on repeat visit. Six dogs (17 per cent) showed an increase in aortic velocity of greater than 20 per cent. Eight dogs (23 per cent) had developed aortic valvular or subvalvular two-dimensional echocardiographic changes that had not been present at the initial visit. Seven dogs (20 per cent) had developed aortic regurgitation, and three dogs (8 per cent) mitral regurgitation.

LINER galaxy properties and the local environment

NASA Astrophysics Data System (ADS)

Coldwell, Georgina V.; Alonso, Sol; Duplancic, Fernanda; Mesa, Valeria

2018-05-01

We analyse the properties of a sample of 5560 low-ionization nuclear emission-line region (LINER) galaxies selected from SDSS-DR12 at low red shift, for a complete range of local density environments. The host LINER galaxies were studied and compared with a well-defined control sample of 5553 non-LINER galaxies matched in red shift, luminosity, morphology and local density. By studying the distributions of galaxy colours and the stellar age population, we find that LINERs are redder and older than the control sample over a wide range of densities. In addition, LINERs are older than the control sample, at a given galaxy colour, indicating that some external process could have accelerated the evolution of the stellar population. The analysis of the host properties shows that the control sample exhibits a strong relation between colours, ages and the local density, while more than 90 per cent of the LINERs are redder and older than the mean values, independently of the neighbourhood density. Furthermore, a detailed study in three local density ranges shows that, while control sample galaxies are redder and older as a function of stellar mass and density, LINER galaxies mismatch the known morphology-density relation of galaxies without low-ionization features. The results support the contribution of hot and old stars to the low-ionization emission although the contribution of nuclear activity is not discarded.

31 CFR 82.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Definitions. 82.3 Section 82.3 Money and Finance: Treasury Regulations Relating to Money and Finance 5-CENT AND ONE-CENT COIN REGULATIONS § 82.3 Definitions. (a) 5-cent coin of the United States means a 5-cent coin minted and issued by the...

31 CFR 82.4 - Penalties.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Penalties. 82.4 Section 82.4 Money and Finance: Treasury Regulations Relating to Money and Finance 5-CENT AND ONE-CENT COIN REGULATIONS § 82.4 Penalties. (a) Any person who exports, melts, or treats 5-cent coins or one-cent coins of the...

76 FR 4395 - Postal Service Price Adjustment

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-25

... the First-Class Mail, single- piece first-ounce letter price; however, the additional-ounce rate for single-piece letters and flats increases from 17 cents to 20 cents. Id. at 12. The price of a single-piece postcard increases from 28 cents to 29 cents. Id. However, to meet the cap average increase for...

38 CFR 3.112 - Fractions of one cent.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Fractions of one cent. 3... Pension, Compensation, and Dependency and Indemnity Compensation Administrative § 3.112 Fractions of one cent. In all cases where the amount to be paid under any award involves a fraction of a cent, the...

Collagen matrix as an inlay in endoscopic skull base reconstruction.

PubMed

Oakley, G M; Christensen, J M; Winder, M; Jonker, B P; Davidson, A; Steel, T; Teo, C; Harvey, R J

2018-03-01

Multi-layer reconstruction has become standard in endoscopic skull base surgery. The inlay component used can vary among autografts, allografts, xenografts and synthetics, primarily based on surgeon preference. The short- and long-term outcomes of collagen matrix in skull base reconstruction are described. A case series of patients who underwent endoscopic skull base reconstruction with collagen matrix inlay were assessed. Immediate peri-operative outcomes (cerebrospinal fluid leak, meningitis, ventriculitis, intracranial bleeding, epistaxis, seizures) and delayed complications (delayed healing, meningoencephalocele, prolapse of reconstruction, delayed cerebrospinal fluid leak, ascending meningitis) were examined. Of 120 patients (51.0 ± 17.5 years, 41.7 per cent female), peri-operative complications totalled 12.7 per cent (cerebrospinal fluid leak, 3.3 per cent; meningitis, 3.3 per cent; other intracranial infections, 2.5 per cent; intracranial bleeding, 1.7 per cent; epistaxis, 1.7 per cent; and seizures, 0 per cent). Delayed complications did not occur in any patients. Collagen matrix is an effective inlay material. It provides robust long-term separation between sinus and cranial cavities, and avoids donor site morbidity, but carries additional cost.

Diagnosis, treatment and outcome of orbital neoplasia in dogs: a retrospective study of 44 cases.

PubMed

Hendrix, D V; Gelatt, K N

2000-03-01

Forty-four dogs with confirmed orbital neoplasia were studied. Eighteen tumour types were represented and 95 per cent of the neoplasms were classified as malignant. The tumour types most commonly diagnosed were osteosarcoma, fibrosarcoma and nasal adenocarcinoma. Thirty-six per cent of the dogs had at least one clinical sign that was compatible with a diagnosis of orbital abscessation or cellulitis. Fifty-six per cent of the dogs, where follow-up information was available, were euthanased or had died within six months of diagnosis, while 19 per cent of the total were still alive after one year post-diagnosis. Cytological examination was diagnostic for orbital neoplasia in 49 per cent of the fine needle aspirates of the retrobulbar space. In contrast, 56 per cent of the non-surgical biopsies were diagnostic for orbital neoplasia. Of those dogs that had died or been euthanased within six months of diagnosis, only 22 per cent had undergone some form of therapy for orbital neoplasia. In comparison, 86 per cent of dogs surviving longer than six months post-diagnosis had undergone such therapy.

Accuracy of diagnoses from magnetic resonance imaging of the knee. A multi-center analysis of one thousand and fourteen patients.

PubMed

Fischer, S P; Fox, J M; Del Pizzo, W; Friedman, M J; Snyder, S J; Ferkel, R D

1991-01-01

Magnetic resonance images of the knee were made for 1014 patients, and the diagnosis was subsequently confirmed arthroscopically. The accuracy of the diagnoses from the imaging was 89 per cent for the medial meniscus, 88 per cent for the lateral meniscus, 93 per cent for the anterior cruciate ligament, and 99 per cent for the posterior cruciate ligament. The magnetic resonance examinations were done at several centers, and the results varied substantially among centers. The accuracy ranged from 64 to 95 per cent for the medial meniscus, from 83 to 94 per cent for the lateral meniscus, and from 78 to 97 per cent for the anterior cruciate ligament. The results from different magnetic-resonance units were also compared, and the findings suggested increased accuracy for the units that had a stronger magnetic field. Of the menisci for which the magnetic resonance signal was reported to be Grade II (a linear intrameniscal signal not extending to the superior or inferior meniscal surface), 17 per cent were found to be torn at arthroscopy.

The X-Shooter Lens Survey - I. Dark matter domination and a Salpeter-type initial mass function in a massive early-type galaxy

NASA Astrophysics Data System (ADS)

Spiniello, C.; Koopmans, L. V. E.; Trager, S. C.; Czoske, O.; Treu, T.

2011-11-01

We present the first results from the X-Shooter Lens Survey: an analysis of the massive early-type galaxy SDSS J1148+1930 at redshift z= 0.444. We combine its extended kinematic profile - derived from spectra obtained with X-Shooter on the European Southern Observatory Very Large Telescope - with strong gravitational lensing and multicolour information derived from Sloan Digital Sky Survey (SDSS) images. Our main results are as follows. (i) The luminosity-weighted stellar velocity dispersion is <σ*>(≲Reff) = 352 ± 10 ± 16 km s-1, extracted from a rectangular aperture of 1.8 × 1.6 arcsec2 centred on the galaxy, more accurate and considerably lower than a previously published value of ˜450 km s-1. (ii) A single-component (stellar plus dark) mass model of the lens galaxy yields a logarithmic total-density slope of γ'= 1.72+0.05- 0.06 (68 per cent confidence level, CL; ?) within a projected radius of ˜2.16 arcsec. (iii) The projected stellar mass fraction, derived solely from the lensing and dynamical data, is f*(90 per cent CL and in some cases violate the total lensing-derived mass limit. We conclude that this very massive early-type galaxy is dark-matter-dominated inside one effective radius, consistent with the trend recently found from massive Sloan Lens ACS (SLACS) galaxies, with a total density slope shallower than isothermal and an IMF normalization consistent with Salpeter.

Open cholecystectomy in the laparoscopic era.

PubMed

Jenkins, P J; Paterson, H M; Parks, R W; Garden, O J

2007-11-01

As techniques in laparoscopic cholecystectomy have improved, surgeon experience of open cholecystectomy may be limited. This study examined the current indications for and techniques used in primary open cholecystectomy. Some 3100 consecutive patients undergoing elective or emergency cholecystectomy over a 5-year interval were identified from a prospective surgical audit database. Demographic, diagnostic and procedural data were examined. There were 123 (4.0 per cent) primary and 219 (7.4 per cent) converted open cholecystectomies. Some 48.0 and 45.6 per cent of patients in the primary open cholecystectomy and converted groups respectively were men, compared with 24.0 per cent of 2758 who had a successful laparoscopic procedure. Primary open cholecystectomy was employed principally for previous upper abdominal open surgery (22.7 per cent) and emergency operation for general peritonitis (19.5 per cent). The fundus-first approach was employed in 53.7 per cent of primary open procedures and 53.0 per cent of conversions, with subtotal excision in 4.9 and 13.2 per cent respectively. Primary open cholecystectomy remains a common procedure in the treatment of gallbladder disease despite the success of laparoscopic cholecystectomy. Successful outcome in difficult cases requires familiarity with specific techniques, exposure to which may be limited in current training programmes. Copyright (c) 2007 British Journal of Surgery Society Ltd.

The food of the lake trout (Cristivomer namaycush namaycush) and of the lawyer (Lota maculosa) of Lake Michigan

USGS Publications Warehouse

Van Oosten, John; Deason, Hilary J.

1938-01-01

This paper reports on a qualitative and quantitative analysis of the contents of 4,979 lake trout stomachs (593 examined in 1930 and 1,253 collected in 1931 from southern Lake Michigan, 1,446 from northern Lake Michigan and 1,687 from Green Bay in 1932), and of a total of 1,528 lawyer stomachs (172 examined in 1930 and 734 collected in 1931 from southern Lake Michigan, 612 from northern Lake Michigan and 10 from Green Bay in 1932). The food of the trout consisted of 98 per cent by volume of fish of which Cottidae and Coregonidae were the principal constituents. Cottidae were dominant in southern Lake Michigan (72 per cent by volume), Coregonidae in northern Lake Michigan (51 per cent) but the lake shiner, Notropis atherinides, was most important in Green Bay in the spring of the year (64 per cent). The lawyer food consisted of 74 per cent by volume of fish and 26 per cent invertebrates. Dominant items were Cottidae (76 per cent by volume) in southern Lake Michigan, Coregonidae (51 per cent) and Pontoporeia (37 per cent) in northern Lake Michigan, and Percopsis (34 per cent) and Mysis (26 per cent) in Green Bay. Data are also presented on the frequency of occurrence (number of stomachs) of the food items and its variation with the sizes of the trout and lawyers, depths of water, seasons, and localities; on the number of individual fish of each species destroyed by the trout and lawyers; and on the calculated volume of the food fishes preceding digestion. The lake trout and lawyer are competitors for the same food, are both predators of the commercially important Coregonidae, and the lawyer through its consumption of invertebrates is a food competitor of the Coregonidae.

Reoperative fundoplications are effective treatment for dysphagia and recurrent gastroesophageal reflux.

PubMed

Rosemurgy, Alexander S; Arnaoutakis, Dean J; Thometz, Donald P; Binitie, Odion; Giarelli, Natalie B; Bloomston, Mark; Goldin, Steve G; Albrink, Michael H

2004-12-01

With wide application of antireflux surgery, reoperations for failed fundoplications are increasingly seen. This study was undertaken to document outcomes after reoperative fundoplications. Sixty-four patients, 26 men and 38 women, of average age 55 years+/-15.6 (SD), underwent reoperative antireflux surgery between 1992 and 2003. Fundoplication prior to reoperation had been undertaken via celiotomy in 27 and laparoscopically in 37. Both before and after reoperative antireflux surgery, patients scored their reflux and dysphagia on a Likert Scale (0 = none, 10 = continuous). Reoperation was undertaken because of dysphagia in 16 per cent, recurrent reflux in 52 per cent (median DeMeester Score 52), or both in 27 per cent. Failure leading to reoperation was due to hiatal failure in 28 per cent, wrap failure in 19 per cent, both in 33 per cent, and slipped Nissen fundoplication in 20 per cent. Laparoscopic reoperations were completed in 49 of 54 patients (91%); 15 had reoperations undertaken via celiotomy. Eighty-eight per cent of reoperations were Nissen fundoplications. With reoperation, Dysphagia Scores improved from 9.5+/-0.7 to 2.6+/-2.8, and Reflux Scores improved from 9.1+/-1.4 to 1.8+/-2.7. Seventy-nine per cent of patients with reflux prior to reoperation, 100 per cent with dysphagia, and 74 per cent with both noted excellent or good outcomes after reoperation. We conclude that failure after fundoplication occurs. Reoperations reduce the severity of dysphagia and reflux, thus salvaging excellent and good outcomes in most. Laparoscopic reoperations are generally possible. Reoperative fundoplications are effective treatment for dysphagia and recurrent gastroesophageal reflux, and their application is encouraged.

A clinical survey on the prevalence and types of cheek teeth disorders present in 400 Zamorano-Leonés and 400 Mirandês donkeys (Equus asinus).

PubMed

Rodrigues, J B; Dixon, P M; Bastos, E; San Roman, F; Viegas, C

2013-12-14

Dental disease is now recognised as a major but often unrecognised disorder of equids, including horses and donkeys. However, very few large clinical studies have documented the prevalence and type of dental disease present in different equid populations and no dental studies have been reported in Zamorano-Leonés or Mirandês donkeys, two endangered donkey breeds. Clinical and detailed oral examinations were performed in 400 Mirandês and 400 Zamorano-Leonés donkeys in Portugal and Spain. It was found that just 4.5 per cent had ever received any previous dental care. Cheek teeth (CT) disorders were present in 82.8 per cent of these donkeys, ranging from a prevalence of 29.6 per cent in the <2.5-year-old group to 100 per cent in the >25-year-old group. These CT disorders included enamel overgrowths (73.1 per cent prevalence but with just 6.3 per cent having associated soft tissue injuries), focal overgrowths (37.3 per cent), periodontal disease (23.5 per cent) and diastemata (19.9 per cent). Peripheral caries was present in 5.9 per cent of cases, but inexplicably, infundibular caries was very rare (1.3 per cent prevalence); this may have been due to their almost fully foraged diet. The high prevalence of enamel overgrowths in these donkeys, most which never received concentrates, also raises questions about the aetiology of this disorder. This very high prevalence of CT disorders, especially in older donkeys, was of great welfare concern in some cases and emphasises the need for routine dental care in these cases on welfare grounds and in order to help preserve these unique breeds.

Evaluation of corneal anaesthesia after the application of topical 2 per cent lidocaine, 0.5 per cent bupivacaine and 1 per cent ropivacaine in dogs.

PubMed

Costa, D; Peña, M T; Ríos, J; Leiva, M

2014-05-10

The objective of this study was to describe and compare the efficacy and duration of topical anaesthesia induced by 2 per cent lidocaine (L), 0.5 per cent bupivacaine (B) and 1 per cent ropivacaine (R) in the dog using 24 clinically healthy beagles with normal ocular examination. Dogs were randomly divided into three groups: 2 per cent lidocaine (n=8), 0.5 per cent bupivacaine (n=8) and 1 per cent ropivacaine (n=8). The baseline corneal touch threshold (CTT) was measured using a Cochet-Bonnet aesthesiometer. Following baseline CTT measurement, a single drop of the assigned anaesthetic was applied to each eye and the CTT was measured bilaterally within one minute after administration and every five minutes until the basal CTT value was restored. Data were analysed with non-parametric analysis of variance models and Dunnet's test for post hoc analysis. One per cent ropivacaine was the most effective drug (LCTTmax=3 cm, BCTTmax=2 cm, RCTTmax=0 cm; P<0.001), and had the shortest latency (LLatency=5 minutes, BLatency=5 minutes, RLatency=1 minute; P<0.001) and the smallest AUC (LAUC=80 cm×minute, BAUC=68.25 cm×minute, RAUC=36.88 cm×minute; P<0.001). There was no statistical difference in the duration of corneal anaesthesia between the groups (P=0.09) and all topical anaesthetics tested reduced corneal sensitivity, although 1 per cent ropivacaine had the maximal and quickest anaesthetic effect. This drug could be used for specific diagnostic procedures where quick and short, but effective, corneal anaesthesia is needed.

Development and testing of novel bisphenol A-free adhesives for lingual fixed retainer bonding.

PubMed

Iliadi, Anna; Eliades, Theodore; Silikas, Nick; Eliades, George

2017-02-01

To comparatively evaluate the properties of two BPA-free experimental adhesives (EXA, EXB) for lingual fixed retainer bonding versus a commercially available reference material (Transbond LR-TLR) based on BPA-compound. The experimental materials were a flowable 60 per cent glass filler-filled UEDMA/TEGDMA flowable composite (EXB) and a 70 per cent glass filler-filled paste composite with PCDMA/UEDMA/TEGDMA co-monomers. The properties tested were degree of conversion (DC%), mechanical properties (Martens hardness-MH, elastic modulus-E IT , elastic index-n IT ), effect of prolonged (6 months) water storage (changes in Vickers microhardness-VHN) and pull-out strength employing a multi-stranded wire. EXB showed the highest DC% (63.6 per cent), followed by EXA (50.5 per cent) and TRL (44.1 per cent), with all means differences being statistically significant (P < 0.05). The statistical rankings of MH (MPa) and E IT (GPa) means were TLR (76.1MPa; 17.3GPa) > EXA (53MPa; 12.9GPa) > EXB (12.9MPa; 6.7GPa), whereas for n IT, EXB (40 per cent) > EXA (34.9 per cent), TLR (33.6 per cent). All materials were affected by prolonged water storage with significant differences among them in VHN. TLR was the most affected material (ΔVHN = -11 per cent), followed by EXA (ΔVHN = -6.8 per cent) and EXB (ΔVHN = -4.2 per cent). No statistically significant differences were found in the pull-out strength testing (24-24.2 N range) and failure mode (70-77 per cent mixed). Considering the differences between the two experimental materials, it may be concluded that the material containing the PCDMA/UEDMA/TEGDMA co-monomers may be used as an alternative to the control. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Dose-expanded study in the reinforcement of efficacy of simvastatin.

PubMed

Vichayanrat, Apichati

2002-04-01

Two hundred and twenty two hyperlipidemic patients were recruited for a 12-week prospective, multicenter, open-label, titrate-to-goal study to evaluate the efficacy and safety of 20 to 40 mg per day of simvastatin in a Thai population. The efficacy on lipid lowering was evaluated at 4 weeks and 8 weeks after medication. Based on NCEP ATP II guideline and ADA position statement, subjects were categorized into three groups according to LDL-C goals; group I: patients without CHD and with < 2 CHD risk factors, group II: patients without CHD and with > or = 2 CHD risk factors and group III: CHD patients or diabetic patients with > or = 1 risk factors. Significant changes of all lipid parameters from baselines were noted at 4 weeks after medication except for HDL-C levels. Reduction of serum LDL-C, TC and TG by 40 per cent, 29 per cent and 16 per cent respectively and increase of serum HDL-C by 5 per cent were observed at 8 weeks of therapy (p<0.05). At 4 weeks after taking simvastatin 20 mg/day, 78.9 per cent of patients in group I, 67.4 per cent in group II and 40.9 per cent in group III achieved LDL-C goals. Seventeen per cent of the patients who were evaluated at 8 weeks increased the simvastatin dosage to 40 mg per day in the second month of treatment. At 8 weeks of therapy with simvastatin 20-40 mg/day, 90.1 per cent of patients in group I, 77.4 per cent in group II and 66.7 per cent in group III achieved LDL-C goals. Adverse symptoms during therapy, mostly mild, developed in 6.3 per cent of the 222 patients. Simvastatin 20-40 mg/day was effective and well tolerated in managing lipid parameters in Thai patients similar to other ethnic populations.

Mortality of emergency abdominal surgery in high-, middle- and low-income countries.

PubMed

2016-07-01

Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1·6 per cent at 24 h (high 1·1 per cent, middle 1·9 per cent, low 3·4 per cent; P < 0·001), increasing to 5·4 per cent by 30 days (high 4·5 per cent, middle 6·0 per cent, low 8·6 per cent; P < 0·001). Of the 578 patients who died, 404 (69·9 per cent) did so between 24 h and 30 days following surgery (high 74·2 per cent, middle 68·8 per cent, low 60·5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2·78, 95 per cent c.i. 1·84 to 4·20) and low-income (OR 2·97, 1·84 to 4·81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. NCT02179112 (http://www.clinicaltrials.gov). © 2016 BJS Society Ltd Published by John Wiley & Sons Ltd.

The metallicity distribution of H I systems in the EAGLE cosmological simulations

NASA Astrophysics Data System (ADS)

Rahmati, Alireza; Oppenheimer, Benjamin D.

2018-06-01

The metallicity of strong H I systems, spanning from damped Lyman α absorbers (DLAs) to Lyman-limit systems (LLSs), is explored between z = 5 → 0 using the EAGLE high-resolution cosmological hydrodynamic simulation of galaxy formation. The metallicities of LLSs and DLAs steadily increase with time in agreement with observations. DLAs are more metal rich than LLSs, although the metallicities in the LLS column density range (N_{H I }≈ 10^{17}-10^{20} cm^{-2}) are relatively flat, evolving from a median H I-weighted metallicity of {Z}≲ 10^{-2} Z_{⊙} at z = 3 to ≈10-0.5 Z⊙ by z = 0. The metal content of H I systems tracks the increasing stellar content of the Universe, holding ≈ 5 {per cent} of the integrated total metals released from stars at z = 0. We also consider partial LLS (pLLS, N_{H I}≈ 10^{16}-10^{17} cm^{-2}) metallicities, and find good agreement with Wotta et al. for the fraction of systems above (37 per cent) and below (63 per cent) 0.1 Z⊙. We also find a large dispersion of pLLS metallicities, although we do not reproduce the observed metallicity bimodality and instead we make the prediction that a larger sample will yield more pLLSs around 0.1 Z⊙. We underpredict the median metallicity of strong LLSs, and predict a population of Z < 10-3 Z⊙ DLAs at z > 3 that are not observed, which may indicate more widespread early enrichment in the real Universe compared to EAGLE.

Herschel-ATLAS: the surprising diversity of dust-selected galaxies in the local submillimetre Universe

NASA Astrophysics Data System (ADS)

Clark, C. J. R.; Dunne, L.; Gomez, H. L.; Maddox, S.; De Vis, P.; Smith, M. W. L.; Eales, S. A.; Baes, M.; Bendo, G. J.; Bourne, N.; Driver, S. P.; Dye, S.; Furlanetto, C.; Grootes, M. W.; Ivison, R. J.; Schofield, S. P.; Robotham, A. S. G.; Rowlands, K.; Valiante, E.; Vlahakis, C.; van der Werf, P.; Wright, A. H.; de Zotti, G.

2015-09-01

We present the properties of the first 250 μm blind sample of nearby galaxies (15 < D < 46 Mpc) containing 42 objects from the Herschel Astrophysical Terahertz Large Area Survey. Herschel's sensitivity probes the faint end of the dust luminosity function for the first time, spanning a range of stellar mass (7.4 < M⋆ < 11.3 log10 M⊙), star formation activity (-11.8 < SSFR < -8.9 log10 yr-1), gas fraction (3-96 per cent), and colour (0.6 < FUV-KS < 7.0 mag). The median cold dust temperature is 14.6 K, colder than in the Herschel Reference Survey (18.5 K) and Planck Early Release Compact Source Catalogue (17.7 K). The mean dust-to-stellar mass ratio in our sample is higher than these surveys by factors of 3.7 and 1.8, with a dust mass volume density of (3.7 ± 0.7) × 105 M⊙ Mpc-3. Counter-intuitively, we find that the more dust rich a galaxy, the lower its UV attenuation. Over half of our dust-selected sample are very blue in FUV-KS colour, with irregular and/or highly flocculent morphology; these galaxies account for only 6 per cent of the sample's stellar mass but contain over 35 per cent of the dust mass. They are the most actively star-forming galaxies in the sample, with the highest gas fractions and lowest UV attenuation. They also appear to be in an early stage of converting their gas into stars, providing valuable insights into the chemical evolution of young galaxies.

Inferring Compton-thick AGN candidates at z > 2 with Chandra using the >8 keV rest-frame spectral curvature

NASA Astrophysics Data System (ADS)

Baronchelli, L.; Koss, M.; Schawinski, K.; Cardamone, C.; Civano, F.; Comastri, A.; Elvis, M.; Lanzuisi, G.; Marchesi, S.; Ricci, C.; Salvato, M.; Trakhtenbrot, B.; Treister, E.

2017-10-01

To fully understand cosmic black hole growth, we need to constrain the population of heavily obscured active galactic nuclei (AGNs) at the peak of cosmic black hole growth (z ˜1-3). Sources with obscuring column densities higher than 1024 atoms cm-2, called Compton-thick (CT) AGNs, can be identified by excess X-ray emission at ˜20-30 keV, called the 'Compton hump'. We apply the recently developed Spectral Curvature (SC) method to high-redshift AGNs (2 < z < 5) detected with Chandra. This method parametrizes the characteristic 'Compton hump' feature cosmologically redshifted into the X-ray band at observed energies <10 keV. We find good agreement in CT AGNs found using the SC method, and bright sources fit using their full spectrum with X-ray spectroscopy. In the Chandra Deep Field-South, we measure a CT fraction of 17^{+19}_{-11} per cent (3/17) for sources with observed luminosity >5 × 1043erg s-1. In the Cosmological Evolution Survey (COSMOS), we find an observed CT fraction of 15^{+4}_{-3} per cent (40/272) or 32 ± 11 per cent when corrected for the survey sensitivity. When comparing to low redshift AGNs with similar X-ray luminosities, our results imply that the CT AGN fraction is consistent with having no redshift evolution. Finally, we provide SC equations that can be used to find high-redshift CT AGNs (z > 1) for current (XMM-Newton) and future (eROSITA and ATHENA) X-ray missions.

The Frontier Fields lens modelling comparison project

NASA Astrophysics Data System (ADS)

Meneghetti, M.; Natarajan, P.; Coe, D.; Contini, E.; De Lucia, G.; Giocoli, C.; Acebron, A.; Borgani, S.; Bradac, M.; Diego, J. M.; Hoag, A.; Ishigaki, M.; Johnson, T. L.; Jullo, E.; Kawamata, R.; Lam, D.; Limousin, M.; Liesenborgs, J.; Oguri, M.; Sebesta, K.; Sharon, K.; Williams, L. L. R.; Zitrin, A.

2017-12-01

Gravitational lensing by clusters of galaxies offers a powerful probe of their structure and mass distribution. Several research groups have developed techniques independently to achieve this goal. While these methods have all provided remarkably high-precision mass maps, particularly with exquisite imaging data from the Hubble Space Telescope (HST), the reconstructions themselves have never been directly compared. In this paper, we present for the first time a detailed comparison of methodologies for fidelity, accuracy and precision. For this collaborative exercise, the lens modelling community was provided simulated cluster images that mimic the depth and resolution of the ongoing HST Frontier Fields. The results of the submitted reconstructions with the un-blinded true mass profile of these two clusters are presented here. Parametric, free-form and hybrid techniques have been deployed by the participating groups and we detail the strengths and trade-offs in accuracy and systematics that arise for each methodology. We note in conclusion that several properties of the lensing clusters are recovered equally well by most of the lensing techniques compared in this study. For example, the reconstruction of azimuthally averaged density and mass profiles by both parametric and free-form methods matches the input models at the level of ∼10 per cent. Parametric techniques are generally better at recovering the 2D maps of the convergence and of the magnification. For the best-performing algorithms, the accuracy in the magnification estimate is ∼10 per cent at μtrue = 3 and it degrades to ∼30 per cent at μtrue ∼ 10.

The bias of the log power spectrum for discrete surveys

NASA Astrophysics Data System (ADS)

Repp, Andrew; Szapudi, István

2018-03-01

A primary goal of galaxy surveys is to tighten constraints on cosmological parameters, and the power spectrum P(k) is the standard means of doing so. However, at translinear scales P(k) is blind to much of these surveys' information - information which the log density power spectrum recovers. For discrete fields (such as the galaxy density), A* denotes the statistic analogous to the log density: A* is a `sufficient statistic' in that its power spectrum (and mean) capture virtually all of a discrete survey's information. However, the power spectrum of A* is biased with respect to the corresponding log spectrum for continuous fields, and to use P_{A^*}(k) to constrain the values of cosmological parameters, we require some means of predicting this bias. Here, we present a prescription for doing so; for Euclid-like surveys (with cubical cells 16h-1 Mpc across) our bias prescription's error is less than 3 per cent. This prediction will facilitate optimal utilization of the information in future galaxy surveys.

Measurement of the lunar neutron density profile. [Apollo 17 flight

NASA Technical Reports Server (NTRS)

Woolum, D. S.; Burnett, D. S.; Furst, M.; Weiss, J. R.

1974-01-01

An in situ measurement of the lunar neutron density from 20 to 400 g/sq cm depth between the lunar surface was made by the Apollo 17 Lunar Neutron Probe Experiment using particle tracks produced by the B10(n, alpha)Li7 reaction. Both the absolute magnitude and depth profile of the neutron density are in good agreement with past theoretical calculations. The effect of cadmium absorption on the neutron density and in the relative Sm149 to Gd157 capture rates obtained experimentally implies that the true lunar Gd157 capture rate is about one half of that calculated theoretically.

75 FR 17832 - Pricing for 2010 Lincoln One-Cent Coin Two-Roll Set

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

... DEPARTMENT OF THE TREASURY United States Mint Pricing for 2010 Lincoln One-Cent Coin Two-Roll Set AGENCY: United States Mint, Department of the Treasury. ACTION: Notice. SUMMARY: The United States Mint is announcing the price of the 2010 Lincoln One-Cent Coin Two-Roll Set. The 2010 Lincoln One-Cent...

A Builder's Guide to Super Good Cents Contruction and Sales.

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

OSU Extension Energy Program; United States. Bonneville Power Administration.

This Builder's guide describes the Super Good Cents {reg sign} program and the benefits available to participating builders. It explains the program standards and the typical building techniques used by Super Good Cents builders. Finally, the guide tells how you can participate and answers many of the questions asked by builders about the Super Good Cents program.

Efficacy of moxidectin against nematodes in naturally infected sheep.

PubMed

Coles, G C; Giordano-Fenton, D J; Tritschler, J P

1994-07-09

The activity of an oral drench of moxidectin against nematodes in naturally infected sheep known to harbour Nematodirus species was evaluated at doses of 0.2 and 0.4 mg/kg bodyweight. Moxidectin was 100 per cent effective against nematodes in the abomasum and 100 per cent effective against nematodes in the small intestine except for adult Trichostrongylus species, against which its efficacy was 94 per cent. It was 100 per cent effective against nematodes in the large intestine except for Trichuris ovis, against which its efficacy was 83 per cent.

ALMA observations of the narrow HR 4796A debris ring

NASA Astrophysics Data System (ADS)

Kennedy, Grant M.; Marino, Sebastian; Matrà, Luca; Panić, Olja; Wilner, David; Wyatt, Mark C.; Yelverton, Ben

2018-04-01

The young A0V star HR 4796A is host to a bright and narrow ring of dust, thought to originate in collisions between planetesimals within a belt analogous to the Solar system's Edgeworth-Kuiper belt. Here we present high spatial resolution 880 μm continuum images from the Atacama Large Millimeter Array. The 80 au radius dust ring is resolved radially with a characteristic width of 10 au, consistent with the narrow profile seen in scattered light. Our modelling consistently finds that the disc is also vertically resolved with a similar extent. However, this extent is less than the beam size, and a disc that is dynamically very cold (i.e. vertically thin) provides a better theoretical explanation for the narrow scattered light profile, so we remain cautious about this conclusion. We do not detect 12CO J=3-2 emission, concluding that unless the disc is dynamically cold the CO+CO2 ice content of the planetesimals is of order a few per cent or less. We consider the range of semi-major axes and masses of an interior planet supposed to cause the ring's eccentricity, finding that such a planet should be more massive than Neptune and orbit beyond 40 au. Independent of our ALMA observations, we note a conflict between mid-IR pericentre-glow and scattered light imaging interpretations, concluding that models where the spatial dust density and grain size vary around the ring should be explored.

Technical and financial evaluation of assays for progesterone in canine practice in the UK.

PubMed

Moxon, R; Copley, D; England, G C W

2010-10-02

The concentration of progesterone was measured in 60 plasma samples from bitches at various stages of the oestrous cycle, using commercially available quantitative and semi-quantitative ELISA test kits, as well as by two commercial laboratories undertaking radioimmunoassay (RIA). The RIA, which was assumed to be the 'gold standard' in terms of reliability and accuracy, was the most expensive method when analysing more than one sample per week, and had the longest delay in obtaining results, but had minimal requirements for practice staff time. When compared with the RIA, the quantitative ELISA had a strong positive correlation (r=0.97, P<0.05) and a sensitivity and specificity of 70.6 per cent and 100.0 per cent, respectively, and positive and negative predictive values of 100.0 per cent and 71.0 per cent, respectively, with an overall accuracy of 90.0 per cent. This method was the least expensive when analysing five or more samples per week, but had longer turnaround times than that of the semi-quantitative ELISA and required more staff time. When compared with the RIA, the semi-quantitative ELISA had a sensitivity and specificity of 100.0 per cent and 95.5 per cent, respectively, and positive and negative predictive values of 73.9 per cent and 77.8 per cent, respectively, with an overall accuracy of 89.2 per cent. This method was more expensive than the quantitative ELISA when analysing five or more samples per week, but had the shortest turnaround time and low requirements in terms of staff time.

Automated cross-identifying radio to infrared surveys using the LRPY algorithm: a case study

NASA Astrophysics Data System (ADS)

Weston, S. D.; Seymour, N.; Gulyaev, S.; Norris, R. P.; Banfield, J.; Vaccari, M.; Hopkins, A. M.; Franzen, T. M. O.

2018-02-01

Cross-identifying complex radio sources with optical or infra red (IR) counterparts in surveys such as the Australia Telescope Large Area Survey (ATLAS) has traditionally been performed manually. However, with new surveys from the Australian Square Kilometre Array Pathfinder detecting many tens of millions of radio sources, such an approach is no longer feasible. This paper presents new software (LRPY - Likelihood Ratio in PYTHON) to automate the process of cross-identifying radio sources with catalogues at other wavelengths. LRPY implements the likelihood ratio (LR) technique with a modification to account for two galaxies contributing to a sole measured radio component. We demonstrate LRPY by applying it to ATLAS DR3 and a Spitzer-based multiwavelength fusion catalogue, identifying 3848 matched sources via our LR-based selection criteria. A subset of 1987 sources have flux density values for all IRAC bands which allow us to use criteria to distinguish between active galactic nuclei (AGNs) and star-forming galaxies (SFG). We find that 936 radio sources ( ≈ 47 per cent) meet both of the Lacy and Stern AGN selection criteria. Of the matched sources, 295 have spectroscopic redshifts and we examine the radio to IR flux ratio versus redshift, proposing an AGN selection criterion below the Elvis radio-loud AGN limit for this dataset. Taking the union of all three AGNs selection criteria we identify 956 as AGNs ( ≈ 48 per cent). From this dataset, we find a decreasing fraction of AGNs with lower radio flux densities consistent with other results in the literature.

Cosmological constraints from galaxy clustering in the presence of massive neutrinos

NASA Astrophysics Data System (ADS)

Zennaro, M.; Bel, J.; Dossett, J.; Carbone, C.; Guzzo, L.

2018-06-01

The clustering ratio is defined as the ratio between the correlation function and the variance of the smoothed overdensity field. In Λ cold dark matter (ΛCDM) cosmologies without massive neutrinos, it has already been proven to be independent of bias and redshift space distortions on a range of linear scales. It therefore can provide us with a direct comparison of predictions (for matter in real space) against measurements (from galaxies in redshift space). In this paper we first extend the applicability of such properties to cosmologies that account for massive neutrinos, by performing tests against simulated data. We then investigate the constraining power of the clustering ratio on cosmological parameters such as the total neutrino mass and the equation of state of dark energy. We analyse the joint posterior distribution of the parameters that satisfy both measurements of the galaxy clustering ratio in the SDSS-DR12, and the angular power spectra of cosmic microwave background temperature and polarization anisotropies measured by the Planck satellite. We find the clustering ratio to be very sensitive to the CDM density parameter, but less sensitive to the total neutrino mass. We also forecast the constraining power the clustering ratio will achieve, predicting the amplitude of its errors with a Euclid-like galaxy survey. First we compute parameter forecasts using the Planck covariance matrix alone, then we add information from the clustering ratio. We find a significant improvement on the constraint of all considered parameters, and in particular an improvement of 40 per cent for the CDM density and 14 per cent for the total neutrino mass.

Environmental management through sluice gated bed-dam: a revived strategy for the control of Anopheles fluviatilis breeding in streams

PubMed Central

Sahu, S.S.; Gunasekaran, K.; Jambulingam, P.

2014-01-01

Background & objectives: Integrated vector management (IVM) emphasizes sustainable eco-friendly methods and minimal use of chemicals. In this context, the present study highlights the environmental control of breeding of Anopheles fluviatilis, the primary malaria vector, through water management in a natural stream in Koraput district, Odisha, India. Methods: The District Rural Development Agency (DRDA), Koraput, constructed two bed-dams across streams, one in Barigaon and the other in Pipalapodar village. The bed-dam in the former village was fitted with two sluice gates whereas the bed dam constructed in the latter village was without the sluice gate. The sluice gates were opened once in a week on a fixed day to flush out the water from the dam. Anopheles immatures were sampled systematically in the streams using a dipper for density measurement and species composition. Results: There was a reduction of 84.9 per cent in the proportion of positive dips for Anopheles larvae/pupae and a reduction of 98.4 per cent in immature density (number/dip) of An. fluviatilis in the experimental downstream compared to the control following opening of the sluice gates. Interpretation & conclusions: Our findins showed that opening of sluice gates of the bed-dam regularly once in a week resulted in the control of vector breeding in the downstream due to the flushing effect of the water released with a high flow from the bed-dam that stagnated water in the upstream. The outcome of the study encourages upscaling this measure to other areas, wherever feasible. PMID:25297364

Redshift-space distortions around voids

NASA Astrophysics Data System (ADS)

Cai, Yan-Chuan; Taylor, Andy; Peacock, John A.; Padilla, Nelson

2016-11-01

We have derived estimators for the linear growth rate of density fluctuations using the cross-correlation function (CCF) of voids and haloes in redshift space. In linear theory, this CCF contains only monopole and quadrupole terms. At scales greater than the void radius, linear theory is a good match to voids traced out by haloes; small-scale random velocities are unimportant at these radii, only tending to cause small and often negligible elongation of the CCF near its origin. By extracting the monopole and quadrupole from the CCF, we measure the linear growth rate without prior knowledge of the void profile or velocity dispersion. We recover the linear growth parameter β to 9 per cent precision from an effective volume of 3( h-1Gpc)3 using voids with radius >25 h-1Mpc. Smaller voids are predominantly sub-voids, which may be more sensitive to the random velocity dispersion; they introduce noise and do not help to improve measurements. Adding velocity dispersion as a free parameter allows us to use information at radii as small as half of the void radius. The precision on β is reduced to 5 per cent. Voids show diverse shapes in redshift space, and can appear either elongated or flattened along the line of sight. This can be explained by the competing amplitudes of the local density contrast, plus the radial velocity profile and its gradient. The distortion pattern is therefore determined solely by the void profile and is different for void-in-cloud and void-in-void. This diversity of redshift-space void morphology complicates measurements of the Alcock-Paczynski effect using voids.

Galaxy evolution in protoclusters

NASA Astrophysics Data System (ADS)

Muldrew, Stuart I.; Hatch, Nina A.; Cooke, Elizabeth A.

2018-01-01

We investigate galaxy evolution in protoclusters using a semi-analytic model applied to the Millennium Simulation, scaled to a Planck cosmology. We show that the model reproduces the observed behaviour of the star formation history (SFH) both in protoclusters and the field. The rate of star formation peaks ∼0.7 Gyr earlier in protoclusters than in the field and declines more rapidly afterwards. This results in protocluster galaxies forming significantly earlier: 80 per cent of their stellar mass is already formed by z = 1.4, but only 45 per cent of the field stellar mass has formed by this time. The model predicts that field and protocluster galaxies have similar average specific star-formation rates (sSFR) at z > 3, and we find evidence of an enhancement of star formation in the dense protoclusters at early times. At z < 3, protoclusters have lower sSFRs, resulting in the disparity between the SFHs. We show that the stellar mass functions of protoclusters are top-heavy compared with the field due to the early formation of massive galaxies, and the disruption and merging of low-mass satellite galaxies in the main haloes. The fundamental cause of the different SFHs and mass functions is that dark matter haloes are biased tracers of the dark matter density field: the high density of haloes and the top-heavy halo mass function in protoclusters result in the early formation then rapid merging and quenching of galaxies. We compare our results with observations from the literature and highlight which observables provide the most informative tests of galaxy formation.

A HARDCORE model for constraining an exoplanet's core size

NASA Astrophysics Data System (ADS)

Suissa, Gabrielle; Chen, Jingjing; Kipping, David

2018-05-01

The interior structure of an exoplanet is hidden from direct view yet likely plays a crucial role in influencing the habitability of the Earth analogues. Inferences of the interior structure are impeded by a fundamental degeneracy that exists between any model comprising more than two layers and observations constraining just two bulk parameters: mass and radius. In this work, we show that although the inverse problem is indeed degenerate, there exists two boundary conditions that enables one to infer the minimum and maximum core radius fraction, CRFmin and CRFmax. These hold true even for planets with light volatile envelopes, but require the planet to be fully differentiated and that layers denser than iron are forbidden. With both bounds in hand, a marginal CRF can also be inferred by sampling in-between. After validating on the Earth, we apply our method to Kepler-36b and measure CRFmin = (0.50 ± 0.07), CRFmax = (0.78 ± 0.02), and CRFmarg = (0.64 ± 0.11), broadly consistent with the Earth's true CRF value of 0.55. We apply our method to a suite of hypothetical measurements of synthetic planets to serve as a sensitivity analysis. We find that CRFmin and CRFmax have recovered uncertainties proportional to the relative error on the planetary density, but CRFmarg saturates to between 0.03 and 0.16 once (Δρ/ρ) drops below 1-2 per cent. This implies that mass and radius alone cannot provide any better constraints on internal composition once bulk density constraints hit around a per cent, providing a clear target for observers.

Precision cosmology with baryons: non-radiative hydrodynamics of galaxy groups

NASA Astrophysics Data System (ADS)

Rabold, Manuel; Teyssier, Romain

2017-05-01

The effect of baryons on the matter power spectrum is likely to have an observable effect for future galaxy surveys, like Euclid or Large Synoptic Survey Telescope (LSST). As a first step towards a fully predictive theory, we investigate the effect of non-radiative hydrodynamics on the structure of galaxy groups sized haloes, which contribute the most to the weak-lensing power spectrum. We perform high-resolution (more than one million particles per halo and one kilo-parsec resolution) non-radiative hydrodynamical zoom-in simulations of a sample of 16 haloes, comparing the profiles to popular analytical models. We find that the total mass profile is well fitted by a Navarro, Frenk & White model, with parameters slightly modified from the dark matter only simulation. We also find that the Komatsu & Seljak hydrostatic solution provides a good fit to the gas profiles, with however significant deviations, arising from strong turbulent mixing in the core and from non-thermal, turbulent pressure support in the outskirts. The turbulent energy follows a shallow, rising linear profile with radius, and correlates with the halo formation time. Using only three main structural halo parameters as variables (total mass, concentration parameter and central gas density), we can predict, with an accuracy better than 20 per cent, the individual gas density and temperature profiles. For the average total mass profile, which is relevant for power spectrum calculations, we even reach an accuracy of 1 per cent. The robustness of these predictions has been tested against resolution effects, different types of initial conditions and hydrodynamical schemes.

Sound wave generation by a spherically symmetric outburst and AGN feedback in galaxy clusters

NASA Astrophysics Data System (ADS)

Tang, Xiaping; Churazov, Eugene

2017-07-01

We consider the evolution of an outburst in a uniform medium under spherical symmetry, having in mind active galactic nucleus feedback in the intracluster medium. For a given density and pressure of the medium, the spatial structure and energy partition at a given time tage (since the onset of the outburst) are fully determined by the total injected energy Einj and the duration tb of the outburst. We are particularly interested in the late phase evolution when the strong shock transforms into a sound wave. We studied the energy partition during such transition with different combinations of Einj and tb. For an instantaneous outburst with tb → 0, which corresponds to the extension of classic Sedov-Taylor solution with counter-pressure, the fraction of energy that can be carried away by sound waves is ≲12 per cent of Einj. As tb increases, the solution approaches the 'slow piston' limit, with the fraction of energy in sound waves approaching zero. We then repeat the simulations using radial density and temperature profiles measured in Perseus and M87/Virgo clusters. We find that the results with a uniform medium broadly reproduce an outburst in more realistic conditions once proper scaling is applied. We also develop techniques to map intrinsic properties of an outburst (Einj, tb and tage) to the observables like the Mach number of the shock and radii of the shock and ejecta. For the Perseus cluster and M87, the estimated (Einj, tb and tage) agree with numerical simulations tailored for these objects with 20-30 per cent accuracy.

Clinical features and natural history of von Hippel-Lindau disease.

PubMed

Maher, E R; Yates, J R; Harries, R; Benjamin, C; Harris, R; Moore, A T; Ferguson-Smith, M A

1990-11-01

The clinical features, age at onset and survival of 152 patients with von Hippel-Lindau disease were studied. Mean age at onset was 26.3 years and 97 per cent of patients had presented by aged 60 years. Retinal angioma was the first manifestation in 65 patients (43 per cent), followed by cerebellar haemangioblastoma (n = 60, 39 per cent) and renal cell carcinoma (n = 15, 10 per cent). Overall, 89 patients (59 per cent) developed a cerebellar haemangioblastoma, 89 (59 per cent) a retinal angioma, 43 (28 per cent) renal cell carcinoma, 20 (13 per cent) spinal haemangioblastoma and 11 (7 per cent) a phaeochromocytoma. Renal, pancreatic and epididymal cysts were frequent findings but their exact incidence was not accurately assessed. Mean age at diagnosis of renal cell carcinoma (44.0 +/- 10.9 years) was significantly older than that for cerebellar haemangioblastoma (29.0 +/- 10.0 years) and retinal angioma (25.4 +/- 12.7 years). The probability of a patient with von Hippel-Lindan disease developing a cerebellar haemangioblastoma, retinal angioma or renal cell carcinoma by age 60 years was 0.84, 0.7 and 0.69, respectively. A comprehensive screening protocol for affected patients and at-risk relatives is presented, based on detailed analysis of age at onset data for each of the major complications. Median actuarial survival was 49 years, with renal cell carcinoma the leading cause of death.

Acute haemorrhagic diarrhoea syndrome in dogs: 108 cases.

PubMed

Mortier, F; Strohmeyer, K; Hartmann, K; Unterer, S

2015-06-13

No prospective studies including large numbers of dogs with acute haemorrhagic diarrhoea syndrome (AHDS) are published so far. The aim of this case-control study was to describe signalment, history, clinical signs, laboratory values and course of disease in dogs with AHDS. Dogs (108) with idiopathic acute haemorrhagic diarrhoea (<3 days) were prospectively enrolled. Clinical assessment was performed by calculation of the 'AHDS index' (0-18). The hospital population and 21 healthy dogs served as control groups. Dogs with AHDS had a significantly lower body weight (median 9.8 kg) and age (median five years) than other dogs of the hospital population (20 kg; 10 years) (P<0.001). Predisposed breeds were Yorkshire terrier, miniature pinscher, miniature schnauzer and Maltese. The syndrome was more likely to occur during winter. Vomiting preceded the onset of bloody diarrhoea in 80 per cent of dogs and haematemesis was observed in half of those cases. Median AHDS index at presentation was 12 (range 3-17). Haematocrit was generally high (median 57.1 per cent; range 33-76 per cent), but exceeded 60 per cent only in 31.4 per cent of dogs. Haematocrit of 48.1 per cent of dogs was above reference range, as was monocyte (50.0 per cent), segmented (59.6 per cent) and band neutrophil count (45.2 per cent). A rapid clinical improvement occurred during the first 48 hours. British Veterinary Association.

Further characterization of field strains of rotavirus from Nigeria VP4 genotype P6 most frequently identified among symptomatically infected children.

PubMed

Adah, M I; Rohwedder, A; Olaleye, O D; Durojaiye, O A; Werchau, H

1997-10-01

Polymerase chain reaction was utilized to characterize the VP4 types of 39 Rotavirus field isolates from symptomatically infected children in Nigeria. Genotype P6 was identified most frequently, occurring in 41.03 per cent of the typed specimens. Genotype P8 was identified as the next most prevalent (33.3% per cent). Genotype p6 was widespread (68.75 per cent) among infected neonates in Southern Nigeria, but mix infection was more prevalent (70 per cent) among Northern Nigerian children. Four distinct strains were identified with four different P genotypes. Overall strain G1P8 predominated (22.22 per cent) followed by G3P6 (17.8 per cent). Strain G1P8 was most prevalent (70 per cent) among infants aged 3.1-9 months, but strain G3P6 was most frequently identified among neonates < or = 3 months (50 per cent). While strain G1P8 was circulating across the country at this time, strain G3P6 was regionally most identified (77.8 per cent) in Southern Nigeria. The presence of untypeable VP4 gene in Nigeria was demonstrated. The occurance of mix infection genotype demonstrates the potential for reassortment events among different rotavirus genogroups in Nigeria. The epidemiological implications of these findings for rotavirus vaccine development and application in the country were discussed.

Experience with the artificial urinary sphincter model AS800 in 148 patients.

PubMed

Fishman, I J; Shabsigh, R; Scott, F B

1989-02-01

The latest version of the artificial urinary sphincter, AS800, was used in 148 patients with urinary incontinence of different etiologies. Followup ranged from 3 to 37 months, with an average of 20.8 months. There were 112 (76 per cent) male and 36 (24 per cent) female patients. The cuff was implanted around the bladder neck in 78 patients (53 per cent) and around the bulbar urethra in 70 (47 per cent). Socially acceptable urinary control was achieved in 90 per cent of the 139 patients with active devices in place. It was necessary to remove the sphincter in 11 patients (7.4 per cent). The reasons for removal were infection and erosion in 8 patients (5.4 per cent), infection without erosion in 2 (1.3 per cent), and erosion due to excess pressure and poor tissues in 1 (0.7 per cent). Comparison of success and failure rates associated with incontinence of different etiologies revealed that patients with incontinence after failure of a conventional antistress incontinence operation and those with incontinence after transurethral resection or radical prostactectomy had the highest success rate, and that patients with incontinence secondary to pelvic fracture or exstrophy and epispadias had the highest failure rates. The deactivation feature (the lock) of the new artificial sphincter model was beneficial for primary deactivation, urethral catheterization or cystoscopy, or for elective nocturnal decompression of the bladder neck or urethral tissues.

A Builder`s Guide to Super Good Cents Contruction and Sales.

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

OSU Extension Energy Program; United States. Bonneville Power Administration.

This Builder`s guide describes the Super Good Cents {reg_sign} program and the benefits available to participating builders. It explains the program standards and the typical building techniques used by Super Good Cents builders. Finally, the guide tells how you can participate and answers many of the questions asked by builders about the Super Good Cents program.

The preplasma effect on the properties of the shock wave driven by a fast electron beam

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

Llor Aisa, E.; Ribeyre, X.; Tikhonchuk, V. T.

2016-08-15

Strong shock wave generation by a mono-energetic fast electron beam in a plasma with an increasing density profile is studied theoretically. The proposed analytical model describes the shock wave characteristics for a homogeneous plasma preceded by a low density precursor. The shock pressure and the time of shock formation depend on the ratio of the electron stopping length to the preplasma areal density and on the initial energy of injected electrons. The conclusions of theoretical model are confirmed in numerical simulations.

A survey of patients' receipt of prescription drug information

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

Morris, L.A.

1982-06-01

A nationwide telephone survey of 1,223 individuals investigated the nature and source of information provided to patients regarding prescription drugs. About half of the respondents said that they had received information from their doctor about the purpose and directions for use for their most recent prescription. Only a few people (11 per cent) said that they had been informed about the drug's side effects and 19 per cent said that they had been told nothing by their doctor. Most (72 per cent) related that nothing had been said to them at the pharmacy. Written information (stickers on the medicine container,more » leaflets or brochures) were said to be infrequently provided at the pharmacy. About 12 per cent of the respondents said they had expected they might get a drug side effect, but only 9 per cent said that they had experienced one. The most frequently cited action in response to side effects was to consult the physician (40 per cent); however, a sizeable percentage of people stopped the medicine completely or temporarily (36 per cent) or kept on taking the drug as prescribed (32 per cent).« less

Suspected side effects of doxycycline use in dogs - a retrospective study of 386 cases.

PubMed

Schulz, B S; Hupfauer, S; Ammer, H; Sauter-Louis, C; Hartmann, K

2011-08-27

This study investigated doxycycline-related side effects in a large population of dogs. Data from 386 dogs that had received doxycycline for the treatment of various infectious diseases were analysed retrospectively. Potential side effects that developed during treatment were documented, and correlations with signalment, dose, duration of treatment, frequency of application, doxycycline preparation and use of additional drugs were investigated. Vomiting was reported in 18.3 per cent of dogs, 7.0 per cent developed diarrhoea and 2.5 per cent developed anorexia. While being treated with doxycycline, 39.4 per cent of dogs showed an increase in alanine aminotransferase (ALT) activity and 36.4 per cent showed an increase in alkaline phosphatase (ALP) activity. There was a dose-related risk of an increase in ALP activity (P=0.011, odds ratio [OR]=1.27, 95 per cent confidence interval [CI] 1.06 to 1.53), and older dogs treated with doxycycline were more likely to develop an increase in ALT activity (P=0.038, OR=1.23, 95 per cent CI 1.01 to 1.50) and vomiting (P=0.017, OR=1.11, 95 per cent CI 1.02 to 1.21).

Latest trends in the assessment and management of paediatric snoring and sleep apnoea.

PubMed

Sharma, S D; Kanona, H; Kumar, G; Kotecha, B

2016-05-01

To investigate the assessment and management of paediatric snoring and obstructive sleep apnoea in UK otolaryngology departments. A telephone questionnaire survey of UK otolaryngology departments was conducted over a 16-week period. The response rate was 61 per cent (85 out of 139 trusts). Use of pre-operative pulse oximetry was reported by 84 per cent of respondents, mainly to diagnose obstructive sleep apnoea (73 per cent) or stratify post-operative risk (46 per cent). Thirty-one per cent of respondents reported using post-operative pulse oximetry. Twenty-five per cent of respondents have a dedicated management protocol for paediatric obstructive sleep apnoea and snoring. Thirty-four per cent require prior clinical commissioning group approval before performing surgery. Fifty-eight per cent of respondents reported following up their obstructive sleep apnoea patients after surgery. The mean follow-up period (±standard deviation) was 6.8 ± 1.2 weeks. There is variation in the assessment and management of paediatric snoring and obstructive sleep apnoea across the UK, particularly in the use of pre- and post-operative pulse oximetry monitoring, and further guidelines regarding this are necessary.

A Tumor-Associated Mutation of FYVE-CENT Prevents Its Interaction with Beclin 1 and Interferes with Cytokinesis

PubMed Central

Sagona, Antonia P.; Nezis, Ioannis P.; Bache, Kristi G.; Haglund, Kaisa; Bakken, Anne Cathrine; Skotheim, Rolf I.; Stenmark, Harald

2011-01-01

The tumor suppressor activity of Beclin 1 (BECN1), a subunit of class III phosphatidylinositol 3-kinase complex, has been attributed to its regulation of apoptosis and autophagy. Here, we identify FYVE-CENT (ZFYVE26), a phosphatidylinositol 3-phosphate binding protein important for cytokinesis, as a novel interacting protein of Beclin 1. A mutation in FYVE-CENT (R1945Q) associated with breast cancer abolished the interaction between FYVE-CENT and Beclin 1, and reduced the localization of these proteins at the intercellular bridge during cytokinesis. Breast cancer cells containing the FYVE-CENT R1945Q mutation displayed a significant increase in cytokinetic profiles and bi - multinuclear phenotype. Both Beclin 1 and FYVE-CENT were found to be downregulated in advanced breast cancers. These findings suggest a positive feedback loop for recruitment of FYVE-CENT and Beclin 1 to the intercellular bridge during cytokinesis, and reveal a novel potential tumor suppressor mechanism for Beclin 1. PMID:21455500

Liver abscess in ancient Greek and Greco-Roman texts.

PubMed

Papavramidou, Niki; Samara, Anastasia; Christopoulou-Aletra, Helen

2014-01-01

This paper presents liver abscesses, as studied in the ancient Greek and Greco-Roman bibliography. Numerous references concerning this entity can be found in the writings of the Hippocratic doctors (5th cent. B.C.), Archigenes of Apamea (1st cent. A.D.), Galen (2nd cent. A.D.), Aretaeus of Cappadocia (2nd cent. A.D), Oribasius (4th cent. A.D.), Theophilus Protospatharius (7th cent. A.D.), and Paulus Nicaeensis (7th-10th cent. A.D.). In most cases the clinical manifestations, the prognosis and the method of treatment are presented. In all ancient writings we studied, the rupture of a liver abscess is also part of the main theme. In specific, the path that the fluid would follow after a rupture was considered to be a main prognostic factor, i.e. if the fluid "coursed into the stomach", the patient would definitely die. In this work, an attempt is also made to correlate the ancient descriptions to modern medical entities, such as amebic or pyogenic liver abscess.

A tumor-associated mutation of FYVE-CENT prevents its interaction with Beclin 1 and interferes with cytokinesis.

PubMed

Sagona, Antonia P; Nezis, Ioannis P; Bache, Kristi G; Haglund, Kaisa; Bakken, Anne Cathrine; Skotheim, Rolf I; Stenmark, Harald

2011-03-24

The tumor suppressor activity of Beclin 1 (BECN1), a subunit of class III phosphatidylinositol 3-kinase complex, has been attributed to its regulation of apoptosis and autophagy. Here, we identify FYVE-CENT (ZFYVE26), a phosphatidylinositol 3-phosphate binding protein important for cytokinesis, as a novel interacting protein of Beclin 1. A mutation in FYVE-CENT (R1945Q) associated with breast cancer abolished the interaction between FYVE-CENT and Beclin 1, and reduced the localization of these proteins at the intercellular bridge during cytokinesis. Breast cancer cells containing the FYVE-CENT R1945Q mutation displayed a significant increase in cytokinetic profiles and bi-multinuclear phenotype. Both Beclin 1 and FYVE-CENT were found to be downregulated in advanced breast cancers. These findings suggest a positive feedback loop for recruitment of FYVE-CENT and Beclin 1 to the intercellular bridge during cytokinesis, and reveal a novel potential tumor suppressor mechanism for Beclin 1.

Bacteria profile and antibiogram of the bacteria isolated from the exposed pulp of dog canine teeth.

PubMed

Almansa Ruiz, José Carlos; Jonker, Annelize; Bosman, Anna-Mari; Steenkamp, Gerhard

2018-04-27

Twenty-seven microbiological samples were taken from root canals (RC) of the canine teeth of 20 dogs where the pulps were non-vital and exposed due to complicated crown fractures. These pulps were cultured for aerobic/anaerobic bacteria. Antimicrobial susceptibility of isolates was determined using the Kirby-Bauer diffusion test. A total of 49 cultivable isolates, belonging to 27 different microbial species and 18 different genera, were recovered from the 27 RCs sampled. Twenty (40.81 per cent) of the cultivable isolates were Gram positive while 29 (59.19 per cent) were Gram negative. Facultative anaerobes were the most common bacteria (77.56 per cent). Aerobic isolates represented 18.36 per cent, and strict anaerobes 4.08 per cent. The antimicrobials with the highest in vitro efficacy were gentamicin (100 per cent) and enrofloxacin (93.32 per cent). © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Helium in the eroding atmosphere of an exoplanet.

PubMed

Spake, J J; Sing, D K; Evans, T M; Oklopčić, A; Bourrier, V; Kreidberg, L; Rackham, B V; Irwin, J; Ehrenreich, D; Wyttenbach, A; Wakeford, H R; Zhou, Y; Chubb, K L; Nikolov, N; Goyal, J M; Henry, G W; Williamson, M H; Blumenthal, S; Anderson, D R; Hellier, C; Charbonneau, D; Udry, S; Madhusudhan, N

2018-05-01

Helium is the second-most abundant element in the Universe after hydrogen and is one of the main constituents of gas-giant planets in our Solar System. Early theoretical models predicted helium to be among the most readily detectable species in the atmospheres of exoplanets, especially in extended and escaping atmospheres 1 . Searches for helium, however, have hitherto been unsuccessful 2 . Here we report observations of helium on an exoplanet, at a confidence level of 4.5 standard deviations. We measured the near-infrared transmission spectrum of the warm gas giant 3 WASP-107b and identified the narrow absorption feature of excited metastable helium at 10,833 angstroms. The amplitude of the feature, in transit depth, is 0.049 ± 0.011 per cent in a bandpass of 98 angstroms, which is more than five times greater than what could be caused by nominal stellar chromospheric activity. This large absorption signal suggests that WASP-107b has an extended atmosphere that is eroding at a total rate of 10 10 to 3 × 10 11 grams per second (0.1-4 per cent of its total mass per billion years), and may have a comet-like tail of gas shaped by radiation pressure.

Comparison of five systems for staging lymph node metastasis in gastric cancer.

PubMed

Yu, W; Choi, G S; Whang, I; Suh, I S

1997-09-01

There are several systems for staging lymph node metastasis in gastric cancer. Their relative merits are not clear. In this retrospective analysis, the nodal status was classified according to the Union Internacional Contra la Cancrum (UICC) and Japanese staging systems, the number and frequency of lymph node metastasis, and the level of involved nodes. Each staging system was scored as good (+1), fair (0) or poor (-1) with respect to prognostic value, theoretical value, convenience, reproducibility and surgical applicability. There were no differences between the five staging systems in predicting survival. The Japanese staging system was most arbitrary owing to the complexity of the system, although it had an advantage in surgical application. The same disadvantage was found in the UICC system and the level system. Determination of the number and frequency of involved nodes was convenient and reproducible, but the number of lymph nodes dissected must be considered when the number of positive nodes is used for staging. The classification of metastasis to the regional lymph nodes as N0 (no nodal metastasis), N1 (metastasis in 1-25 per cent of dissected nodes) and N2 (metastasis in more than 25 per cent of dissected nodes) would be a simple, convenient, reproducible staging system with an ability to predict surgical results.

Implications of the interstellar object 1I/'Oumuamua for planetary dynamics and planetesimal formation

NASA Astrophysics Data System (ADS)

Raymond, Sean N.; Armitage, Philip J.; Veras, Dimitri; Quintana, Elisa V.; Barclay, Thomas

2018-05-01

'Oumuamua, the first bona fide interstellar planetesimal, was discovered passing through our Solar system on a hyperbolic orbit. This object was likely dynamically ejected from an extrasolar planetary system after a series of close encounters with gas giant planets. To account for 'Oumuamua's detection, simple arguments suggest that ˜1 M⊕ of planetesimals are ejected per solar mass of Galactic stars. However, that value assumes mono-sized planetesimals. If the planetesimal mass distribution is instead top-heavy, the inferred mass in interstellar planetesimals increases to an implausibly high value. The tension between theoretical expectations for the planetesimal mass function and the observation of 'Oumuamua can be relieved if a small fraction ({˜ } 0.1-1 {per cent}) of planetesimals are tidally disrupted on the pathway to ejection into 'Oumuamua-sized fragments. Using a large suite of simulations of giant planet dynamics including planetesimals, we confirm that 0.1-1 per cent of planetesimals pass within the tidal disruption radius of a gas giant on their pathway to ejection. 'Oumuamua may thus represent a surviving fragment of a disrupted planetesimal. Finally, we argue that an asteroidal composition is dynamically disfavoured for 'Oumuamua, as asteroidal planetesimals are both less abundant and ejected at a lower efficiency than cometary planetesimals.

The EAGLE simulations: atomic hydrogen associated with galaxies

NASA Astrophysics Data System (ADS)

Crain, Robert A.; Bahé, Yannick M.; Lagos, Claudia del P.; Rahmati, Alireza; Schaye, Joop; McCarthy, Ian G.; Marasco, Antonino; Bower, Richard G.; Schaller, Matthieu; Theuns, Tom; van der Hulst, Thijs

2017-02-01

We examine the properties of atomic hydrogen (H I) associated with galaxies in the Evolution and Assembly of GaLaxies and their Environments (EAGLE) simulations of galaxy formation. EAGLE's feedback parameters were calibrated to reproduce the stellar mass function and galaxy sizes at z = 0.1, and we assess whether this calibration also yields realistic H I properties. We estimate the self-shielding density with a fitting function calibrated using radiation transport simulations, and correct for molecular hydrogen with empirical or theoretical relations. The `standard-resolution' simulations systematically underestimate H I column densities, leading to an H I deficiency in low-mass (M⋆ < 1010 M⊙) galaxies and poor reproduction of the observed H I mass function. These shortcomings are largely absent from EAGLE simulations featuring a factor of 8 (2) better mass (spatial) resolution, within which the H I mass of galaxies evolves more mildly from z = 1 to 0 than in the standard-resolution simulations. The largest volume simulation reproduces the observed clustering of H I systems, and its dependence on H I richness. At fixed M⋆, galaxies acquire more H I in simulations with stronger feedback, as they become associated with more massive haloes and higher infall rates. They acquire less H I in simulations with a greater star formation efficiency, since the star formation and feedback necessary to balance the infall rate is produced by smaller gas reservoirs. The simulations indicate that the H I of present-day galaxies was acquired primarily by the smooth accretion of ionized, intergalactic gas at z ≃ 1, which later self-shields, and that only a small fraction is contributed by the reincorporation of gas previously heated strongly by feedback. H I reservoirs are highly dynamic: over 40 per cent of H I associated with z = 0.1 galaxies is converted to stars or ejected by z = 0.

Galactic foreground contributions to the 5-year Wilkinson Microwave Anisotropy Probe maps

NASA Astrophysics Data System (ADS)

Macellari, N.; Pierpaoli, E.; Dickinson, C.; Vaillancourt, J. E.

2011-12-01

We compute the cross-correlation between intensity and polarization from the 5-year Wilkinson Microwave Anisotropy Probe (WMAP5) data in different sky regions with respect to template maps for synchrotron, dust and free-free emission. We derive the frequency dependence and polarization fraction for all three components in 48 different sky regions of HEALPIX (Nside= 2) pixelization. The anomalous emission associated with dust is clearly detected in intensity over the entire sky at the K (23-GHz) and Ka (33-GHz) WMAP bands, and is found to be the dominant foreground at low Galactic latitudes, between b =-40° and +10°. The synchrotron spectral index obtained from the K and Ka WMAP bands from an all-sky analysis is βs=-3.32 ± 0.12 for intensity and βs=-3.01 ± 0.03 for polarized intensity. The polarization fraction of the synchrotron emission is constant in frequency and increases with latitude from ≈5 per cent near the Galactic plane up to ≈40 per cent in some regions at high latitudes; the average value for |b| < 20° is 8.6 ± 1.7 (stat) ± 0.5 (sys) per cent, while for |b| > 20°, it is 19.3 ± 0.8 (stat) ± 0.5 (sys) per cent. Anomalous dust and free-free emissions appear to be relatively unpolarized. Monte Carlo simulations showed that there were biases of the method due to cross-talk between the components, at up to ≈5 per cent in any given pixel, and ≈1.5 per cent on average, when the true polarization fraction is low (a few per cent or less). Nevertheless, the average polarization fraction of dust-correlated emission at the K band is 3.2 ± 0.9 (stat) ± 1.5 (sys) per cent or less than 5 per cent at 95 per cent confidence. When comparing real data with simulations, eight regions show a detected polarization above the 99th percentile of the distribution from simulations with no input foreground polarization, six of which are detected at above 2σ and display polarization fractions between 2.6 and 7.2 per cent, except for one anomalous region, which has 32 ± 12 per cent. The dust polarization values are consistent with the expectation from spinning dust emission, but polarized dust emission from magnetic-dipole radiation cannot be ruled out. Free-free emission was found to be unpolarized with an upper limit of 3.4 per cent at 95 per cent confidence.

Facial burns in children: a series analysis with implications for resuscitation and forensic odontology.

PubMed

Acton, C; Nixon, J; Pearn, J; Williams, D; Leditschke, F

1999-03-01

This study comprises a continuous (1981-1995) unselected series of all children who died from thermal injuries in the State of Queensland, Australia. One hundred and six children, so identified, died from incineration (35 per cent), respiratory burns with smoke or carbon monoxide inhalation (33 per cent), body surface area burns comprising greater than 60 per cent (9 per cent) and electrocution (20 per cent). The burn fatality rate was 0.98 per hundred thousand children (0-14 years) per year, with no secular trend and, specifically, no reduction in the annual rate of such fatalities. Eighty-two children (49 males) had concomitant facial injuries, both thermal and nonthermal; of whom 55 per cent were under the age of five years. Sixty (73 per cent) child burn victims died in house fires. Forensic odontology is important in confirming the age of such victims in single incinerations but is of limited value when larger numbers of children are incinerated, because of the relative lack of dental restorations in the infant and pre-school age group. Of the 82 children with facial and airway injuries, 12 per cent had only mild or superficial facial damage and only seven (8 per cent) were alive or resuscitable at the time of rescue from the conflagration or burning injury. child deaths from burns contributed an annual loss rate of 506 years of potential life lost (YPLL) in a population of 3 million of whom 21.5 per cent were children under the age of 15 years. Airway management and resuscitation, in the context of managing surviving burn victims of any age with facial injuries, pose special difficulties. Inhalational burns (smoke and the gases of conflagration) result in a mortality greater than 60 per cent. Although 81 per cent of children showed evidence of airway obstruction, analysis of current data indicates that a maximum of 8 per cent could have survived with airway maintenance and protection. Inhalational burns (to both upper and lower airways) grossly reduce survivability. Primary prevention would seem vital and thus remains a major challenge to reduce the incidence of such deaths. Some strategies include advocacy to promote the compulsory installation of smoke alarms, family drills to practise escape and the teaching of 'first aid for all'

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

Yang, Weitao

This Special Topic Issue on the Advances in Density Functional Theory, published as a celebration of the fifty years of density functional theory, contains a retrospective article, a perspective article, and a collection of original research articles that showcase recent theoretical advances in the field. It provides a timely discussion reflecting a cross section of our understanding, and the theoretical and computational developments, which have significant implications in broad areas of sciences and engineering.

ForCent model development and testing using the Enriched Background Isotope Study experiment

Treesearch

William J. Parton; Paul J. Hanson; Chris Swanston; Margaret Torn; Susan E. Trumbore; William Riley; Robin Kelly

2010-01-01

The ForCent forest ecosystem model was developed by making major revisions to the DayCent model including: (1) adding a humus organic pool, (2) incorporating a detailed root growth model, and (3) including plant phenological growth patterns. Observed plant production and soil respiration data from 1993 to 2000 were used to demonstrate that the ForCent model could...

Prospective cohort study to assess rates of contagious disease in pre-weaned UK dairy heifers: management practices, passive transfer of immunity and associated calf health

PubMed Central

Johnson, Kate F; Chancellor, Natalie; Burn, Charlotte C; Wathes, D Claire

2017-01-01

Dairy calves are vulnerable to infectious diseases, particularly diarrhoea and bovine respiratory disease (BRD), causing mortality and reducing welfare and growth. A prospective cohort study was performed on 11 UK dairy farms to determine the underlying causes for calf disease. This first paper describes the incidence, timing and duration of infectious disease, mortality rates, passive transfer of immunity and key management practices that may contribute to disease incidence. Heifer calves were recruited in the first week of life (n=492) and a blood sample taken to measure IgG and total protein (TP). Each animal was examined weekly for nine weeks using a standardised health scoring system. Recruitment of calves occurred between August and February. Four farms provided supplementary colostrum to more than 75 per cent of calves born, whereas on the remainder only 0 to 19 per cent were supplemented. Mean serum IgG and TP were 19.0±10 and 56.7±10.3 mg/ml respectively, with 20.7 per cent (95CI: 17.2 to 24.7 per cent) of all calves classified as having failure of passive transfer (IgG <10 mg/ml). The overall preweaning mortality rate was 4.5 per cent. (95 per cent CI: 2.9 to 6.8 per cent). During this period,48.2 per cent of all calves (range 24.1 to 74.4 per cent between farms) were diagnosed with diarrhoea and 45.9 per cent (range 20.4 to 77.8 per cent) with BRD. The incidence rates were 7.8 cases of diarrhoea and 10.1 cases of BRD per 100 calf weeks at risk, respectively. Rates of infectious disease were therefore high despite relatively good passive transfer. PMID:29259784

Motile Salmonella serotypes causing high mortality in poultry farms in three South-Western States of Nigeria

PubMed Central

Ibrahim, Najume Doguwar-Giginya; Saidu, Shehu NaAllah; Azeez, Aminullah Ajiyobiojo; Akinduti, Paul Akinniyi; Kwanashie, Clara Nna; Fakilahyel Kadiri, Amina Kinta; Muhammed, Maryam; Fagbamila, Idowu Oluwabunmi; Luka, Pam Dachung

2017-01-01

This study was carried out to identify the Salmonella serotypes causing high mortality in chickens in Lagos, Ogun and Oyo states, Nigeria. Chickens presented for postmortem examination during disease outbreaks that were characterised by high mortality (40 per cent to 80 per cent) in poultry farms in the study area were examined from January to December, 2013. Samples of the lungs, heart, liver, spleen, kidneys, proventriculus, intestine and caecum were collected from suspected cases of salmonellosis, for bacterial culture and identification. Salmonella isolates were confirmed using PCR and serotyped using the Kauffman-White scheme. Twenty-six day-old pullets were raised to two weeks and inoculated orally with 0.2 mL of 1×108 colony forming units of Salmonella Zega identified in the present study to determine their pathogenicity, while another 26 served as control. The Salmonella serotypes were S Zega (n=13; 35.14 per cent), Salmonella Kentucky (n=9; 24.32 per cent), Salmonella Herston (n=6; 16.22 per cent), Salmonella Nima (n=4; 10.81 per cent), Salmonella Telelkebir (n=3; 8.11 per cent), Salmonella Colindale (n=1; 2.70 per cent) and Salmonella Tshiongwe (n=1; 2.70 per cent). Clinical signs in both natural and experimental infections were acute (70 per cent) and chronic (30 per cent), and included weakness, anorexia, yellowish diarrhoea, pasted vents, somnolescence and mortality, while gross lesions showed marked pulmonary congestion and oedema, necrotic foci in the myocardium; the liver, spleen and kidneys were markedly enlarged and had subcapsular multifocal necrosis. There were catarrhal proventriculitis and enteritis, and haemorrhagic typhlitis. While most of the serotypes identified in the present study have been isolated from poultry sources from commercial farms in Nigeria, to the best of the authors' knowledge, they have not been previously reported to cause high mortality in chickens in the study area. PMID:29344363

A comparative study between 10 per cent sulfur ointment and 0.3 per cent gamma benzene hexachloride gel in the treatment of scabies in children.

PubMed

Singalavanija, Srisupalak; Limpongsanurak, Wanida; Soponsakunkul, Siritorn

2003-08-01

Scabies is a common contagious skin disease in children. Treatment of scabies in infants and children is the subject of worldwide concern because of risk and benefit of the variety of scabicides. To compare the efficacy of 10 per cent sulfur ointment and 0.3 per cent gamma benzene hexachloride gel for the treatment of scabies in children. A randomized investigator blind study was conducted to compare the efficacy of 10 per cent sulfur ointment and 0.3 per cent gamma benzene hexachloride (GBH) for the treatment of scabies in children at Queen Sirikit National Institute of Child Health from December 1999 to May 2000. Diagnosis was made by the clinical signs of excoriated papules in the classic distribution with nocturnal pruritus and family history of similar symptoms. Diagnosis for all patients was confirmed by positive skin scrapings for eggs, larva, mites or fecal pellets by light microscopy. Patients were followed-up at intervals of 2 and 4 weeks. One hundred children with an age range from 6 months to 13 years were randomized into 2 groups, 10 per cent sulfur group (50 cases) and 0.3 per cent GBH (50 cases). Age, sex, history of contact cases and clinical manifestations were not statistically different between the two groups. After 4 weeks of treatment, there were no statistical differences between the two groups in patients assessed cured (92% vs 94%), clinical cure (92% vs 91%) and parasitic cure (83% vs 84%). The adverse effect of foul odor in the sulfur group was more common than in the GBH group (p < 0.05). 10 per cent sulfur ointment is as safe and efficacious as 0.3 per cent GBH for the treatment of scabies in children.

Accelerations in Flight

NASA Technical Reports Server (NTRS)

Doolittle, J H

1925-01-01

This work on accelerometry was done at McCook Field for the purpose of continuing the work done by other investigators and obtaining the accelerations which occur when a high-speed pursuit airplane is subjected to the more common maneuvers. The accelerations obtained in suddenly pulling out of a dive with well-balanced elevators are shown to be within 3 or 4 per cent of the theoretically possible accelerations. The maximum acceleration which a pilot can withstand depends upon the length of time the acceleration is continued. It is shown that he experiences no difficulty under the instantaneous accelerations as high as 7.8 G., but when under accelerations in excess of 4.5 G., continued for several seconds, he quickly loses his faculties.

A modified Friedmann equation for a system with varying gravitational mass

NASA Astrophysics Data System (ADS)

Gorkavyi, Nick; Vasilkov, Alexander

2018-05-01

The Laser Interferometer Gravitational-Wave Observatory (LIGO) detection of gravitational waves that take away 5 per cent of the total mass of two merging black holes points out on the importance of considering varying gravitational mass of a system. Using an assumption that the energy-momentum pseudo-tensor of gravitational waves is not considered as a source of gravitational field, we analyse a perturbation of the Friedmann-Robertson-Walker metric caused by the varying gravitational mass of a system. This perturbation leads to a modified Friedmann equation that contains a term similar to the `cosmological constant'. Theoretical estimates of the effective cosmological constant quantitatively corresponds to observed cosmological acceleration.

Theory of spiral structure.

NASA Technical Reports Server (NTRS)

Lin, C. C.

1971-01-01

The question whether the galactic spiral arms are material objects or wave patterns is discussed. A semiempirical approach is adopted in presenting the concept of density waves. The theory of density waves is considered, giving attention to a survey of theoretical developments by analytical methods, the implication of a spiral pattern of density waves, spirals with moderately small pitch angle, and the origin and permanence of galactic spirals. The theoretical aspects discussed are tested against more detailed observations in the Milky Way system. It is pointed out that the density wave concept introduced by Lindblad, including the material concentration of both gas and stars, is the essential basis for the spiral structure of disk-shaped galaxies.

When combined X-ray and polarized neutron diffraction data challenge high-level calculations: spin-resolved electron density of an organic radical.

PubMed

Voufack, Ariste Bolivard; Claiser, Nicolas; Lecomte, Claude; Pillet, Sébastien; Pontillon, Yves; Gillon, Béatrice; Yan, Zeyin; Gillet, Jean Michel; Marazzi, Marco; Genoni, Alessandro; Souhassou, Mohamed

2017-08-01

Joint refinement of X-ray and polarized neutron diffraction data has been carried out in order to determine charge and spin density distributions simultaneously in the nitronyl nitroxide (NN) free radical Nit(SMe)Ph. For comparison purposes, density functional theory (DFT) and complete active-space self-consistent field (CASSCF) theoretical calculations were also performed. Experimentally derived charge and spin densities show significant differences between the two NO groups of the NN function that are not observed from DFT theoretical calculations. On the contrary, CASSCF calculations exhibit the same fine details as observed in spin-resolved joint refinement and a clear asymmetry between the two NO groups.

Testing for a Debt-Threshold Effect on Output Growth.

PubMed

Lee, Sokbae; Park, Hyunmin; Seo, Myung Hwan; Shin, Youngki

2017-12-01

Using the Reinhart-Rogoff dataset, we find a debt threshold not around 90 per cent but around 30 per cent, above which the median real gross domestic product (GDP) growth falls abruptly. Our work is the first to formally test for threshold effects in the relationship between public debt and median real GDP growth. The null hypothesis of no threshold effect is rejected at the 5 per cent significance level for most cases. While we find no evidence of a threshold around 90 per cent, our findings from the post-war sample suggest that the debt threshold for economic growth may exist around a relatively small debt-to-GDP ratio of 30 per cent. Furthermore, countries with debt-to-GDP ratios above 30 per cent have GDP growth that is 1 percentage point lower at the median.

Electrical burns in Kuwait: a review and analysis of 64 cases.

PubMed

Gang, R K; Bajec, J

1992-12-01

Sixty-four patients with electrical burns were admitted to the Department of Plastic Surgery, Ibn Sina Hospital, Kuwait during the past 6 years. There were 1202 admissions during this period, the incidence of electrical burns being 5.3 per cent. Sixty-nine per cent of the patients sustained injury from direct contact with live electrical wire, the remaining 31 per cent sustained flash burns. The incidence of low voltage injury was much higher as compared to high voltage. Forty-four per cent of these injuries were not work related. Less than 10 per cent of the body surface area was involved in about 80 per cent of the patients. A total of 65 operations was carried out in 39 patients. Twenty of these patients had repeated debridements until the wound was ready for coverage. All 64 patients survived.

Testing for a Debt‐Threshold Effect on Output Growth†

PubMed Central

Lee, Sokbae; Park, Hyunmin; Seo, Myung Hwan; Shin, Youngki

2017-01-01

Abstract Using the Reinhart–Rogoff dataset, we find a debt threshold not around 90 per cent but around 30 per cent, above which the median real gross domestic product (GDP) growth falls abruptly. Our work is the first to formally test for threshold effects in the relationship between public debt and median real GDP growth. The null hypothesis of no threshold effect is rejected at the 5 per cent significance level for most cases. While we find no evidence of a threshold around 90 per cent, our findings from the post‐war sample suggest that the debt threshold for economic growth may exist around a relatively small debt‐to‐GDP ratio of 30 per cent. Furthermore, countries with debt‐to‐GDP ratios above 30 per cent have GDP growth that is 1 percentage point lower at the median. PMID:29263562

Survey of quantitative antimicrobial consumption in two different pig finishing systems.

PubMed

Moreno, M A

2012-09-29

The primary objectives of this study were to: (a) collect on-farm antimicrobial use (AMU) data in fattener pigs employing two questionnaire-based surveys; (b) assess different quantitative measures for quantifying AMU in fattener pigs; (c) compare AMU in fattener pigs between two different management systems producing finishers: farrow-to-finish (FtF) farms versus finisher farms. Two questionnaires were designed both containing five groups of questions focused on the responder, the farm and AMU (eg, in-feed, in-drinking water and parenteral); both surveys were carried out by means of personal face-to-face interviews. Both surveys started with a sample size of 108 potentially eligible farms per survey; nevertheless, finally 67 finisher farms and 49 FtF farms were recruited. Overall percentages of animals exposed to antimicrobials (AM) were high (90 per cent in finisher farms and 54 per cent FtF farms); colistin (61 per cent and 33 per cent) and doxycycline (62 per cent and 23 per cent) were the most common AMs, followed by amoxicillin (51 per cent and 19 per cent) and lincomycin (49 per cent), respectively. Questionnaire-based surveys using face-to-face interviews are useful for capturing information regarding AMU at the farm level. Farm-level data per administration route can be used for comparative AMU analysis between farms. Nevertheless, for the analysis of the putative relationships between AMU and AM resistance, measures based on exposed animals or exposure events are needed.

Verocytotoxigenic Escherichia coli O157 in animals on public amenity premises in England and Wales, 1997 to 2007.

PubMed

Pritchard, G C; Smith, R; Ellis-Iversen, J; Cheasty, T; Willshaw, G A

2009-05-02

At the request of the public health authorities, 31 public amenity premises in England and Wales containing animals of various species were investigated for the presence of verocytotoxigenic Escherichia coli (VTEC) O157 between 1997 and 2007, because of putative associations with human cases. VTEC O157 was confirmed in one or more species on 19 (61.3 per cent) of the premises. There were significant associations between the presence of VTEC O157 and the number of species sampled, the size of the enterprise, the presence of young cattle and the presence of adult pigs. E coli O157 was isolated from 305 (17.8 per cent) of 1715 samples taken from all the premises, and verocytotoxin genes were detected by PCR in 184 (98.4 per cent) of 187 representative isolates. On positive premises, the highest mean proportion of positive samples (29.0 per cent) was in cattle, followed by sheep (24.4 per cent), donkeys (14.6 per cent), pigs (14.3 per cent), horses (12.3 per cent) and goats (9.9 per cent). A high proportion of positive samples was obtained from camelid species sampled on three of the premises. The main phage types (PT) were 2 and 21/28, which were those most commonly isolated from human cases during the same period. A single PT was detected on 14 of the 19 positive premises, with up to six different species having the same PT.

XMM-Newton 13H deep field - I. X-ray sources

NASA Astrophysics Data System (ADS)

Loaring, N. S.; Dwelly, T.; Page, M. J.; Mason, K.; McHardy, I.; Gunn, K.; Moss, D.; Seymour, N.; Newsam, A. M.; Takata, T.; Sekguchi, K.; Sasseen, T.; Cordova, F.

2005-10-01

We present the results of a deep X-ray survey conducted with XMM-Newton, centred on the UK ROSAT13H deep field area. This region covers 0.18 deg2, and is the first of the two areas covered with XMM-Newton as part of an extensive multiwavelength survey designed to study the nature and evolution of the faint X-ray source population. We have produced detailed Monte Carlo simulations to obtain a quantitative characterization of the source detection procedure and to assess the reliability of the resultant sourcelist. We use the simulations to establish a likelihood threshold, above which we expect less than seven (3 per cent) of our sources to be spurious. We present the final catalogue of 225 sources. Within the central 9 arcmin, 68 per cent of source positions are accurate to 2 arcsec, making optical follow-up relatively straightforward. We construct the N(>S) relation in four energy bands: 0.2-0.5, 0.5-2, 2-5 and 5-10 keV. In all but our highest energy band we find that the source counts can be represented by a double power law with a bright-end slope consistent with the Euclidean case and a break around 10-14yergcm-2s-1. Below this flux, the counts exhibit a flattening. Our source counts reach densities of 700, 1300, 900 and 300 deg-2 at fluxes of 4.1 × 10-16,4.5 × 10-16,1.1 × 10-15 and 5.3 × 10-15ergcm-2s-1 in the 0.2-0.5, 0.5-2, 2-5 and 5-10 keV energy bands, respectively. We have compared our source counts with those in the two Chandra deep fields and Lockman hole, and found our source counts to be amongst the highest of these fields in all energy bands. We resolve >51 per cent (>50 per cent) of the X-ray background emission in the 1-2 keV (2-5 keV) energy bands.

Deep 20-GHz survey of the Chandra Deep Field South and SDSS Stripe 82: source catalogue and spectral properties

NASA Astrophysics Data System (ADS)

Franzen, Thomas M. O.; Sadler, Elaine M.; Chhetri, Rajan; Ekers, Ronald D.; Mahony, Elizabeth K.; Murphy, Tara; Norris, Ray P.; Waldram, Elizabeth M.; Whittam, Imogen H.

2014-04-01

We present a source catalogue and first results from a deep, blind radio survey carried out at 20 GHz with the Australia Telescope Compact Array, with follow-up observations at 5.5, 9 and 18 GHz. The Australia Telescope 20 GHz (AT20G) deep pilot survey covers a total area of 5 deg2 in the Chandra Deep Field South and in Stripe 82 of the Sloan Digital Sky Survey. We estimate the survey to be 90 per cent complete above 2.5 mJy. Of the 85 sources detected, 55 per cent have steep spectra (α _{1.4}^{20} < -0.5) and 45 per cent have flat or inverted spectra (α _{1.4}^{20} ≥ -0.5). The steep-spectrum sources tend to have single power-law spectra between 1.4 and 18 GHz, while the spectral indices of the flat- or inverted-spectrum sources tend to steepen with frequency. Among the 18 inverted-spectrum (α _{1.4}^{20} ≥ 0.0) sources, 10 have clearly defined peaks in their spectra with α _{1.4}^{5.5} > 0.15 and α 9^{18} < -0.15. On a 3-yr time-scale, at least 10 sources varied by more than 15 per cent at 20 GHz, showing that variability is still common at the low flux densities probed by the AT20G-deep pilot survey. We find a strong and puzzling shift in the typical spectral index of the 15-20-GHz source population when combining data from the AT20G, Ninth Cambridge and Tenth Cambridge surveys: there is a shift towards a steeper-spectrum population when going from ˜1 Jy to ˜5 mJy, which is followed by a shift back towards a flatter-spectrum population below ˜5 mJy. The 5-GHz source-count model by Jackson & Wall, which only includes contributions from FRI and FRII sources, and star-forming galaxies, does not reproduce the observed flattening of the flat-spectrum counts below ˜5 mJy. It is therefore possible that another population of sources is contributing to this effect.

Australian Students in a Digital World. Policy Insights, Issue #3

ERIC Educational Resources Information Center

Thomson, Sue

2015-01-01

This century has seen continued exponential growth in the use of digital technologies. In Australia, the proportion of students having access to a computer at home rose from about 91 per cent in 2000 to over 99 per cent in 2013, and access to the internet grew from 67 per cent in 2000 to 98 per cent in 2013. According to the 2013 report on the…

Satellite characterization of four interesting sites for astronomical instrumentation

NASA Astrophysics Data System (ADS)

Cavazzani, S.; Zitelli, V.

2013-03-01

In this paper we have evaluated the amount of available telescope time at four interesting sites for astronomical instrumentation. We use the GOES 12 data for years 2008 and 2009. We use a homogeneous methodology presented in several previous papers to classify the nights as clear (completely cloud-free), mixed (partially cloud-covered) or covered. Additionally, for the clear nights we have evaluated the number of satellite-stable nights, corresponding to the number of ground-based photometric nights, and the clear nights, corresponding to the spectroscopic nights. We have applied this model to two sites in the Northern Hemisphere (San Pedro Martir (SPM), Mexico and Izaña, Canary Islands) and to two sites in the Southern Hemisphere (El Leoncito, Argentina and San Antonio de Los Cobres (SAC), Argentina). We have obtained, for the two years considered, mean percentages of cloud-free nights of 68.6 per cent at Izaña, 76.0 per cent at SPM, 70.6 per cent at Leoncito and 70.0 per cent at SAC. We have evaluated, amongst the cloud-free nights, a proportion of stable nights of 62.6 per cent at Izaña, 69.6 per cent at SPM, 64.9 per cent at Leoncito and 59.7 per cent at SAC.

Prevalence of cardiovascular risk factors in the urban population of Soussa in Tunisia.

PubMed

Ghannem, H; Hadj Fredj, A

1997-12-01

With the epidemiological transition phenomenon, Tunisia is now facing the growing prevalence of chronic diseases. Environmental and behavioural changes such as the adoption of new dietary habits and a sedentary lifestyle, and the stress of urbanization and of working conditions all lead to the rise in cardiovascular disease (CVD) risk factors. The aim of this study is to estimate the prevalence of the main CVD risk factors in an urban context. For this, we have undertaken a household epidemiological survey of a representative sample of the adult urban population of Soussa, Tunisia (n = 957). This study shows high prevalences of hypertension (blood pressure >160/95 mmHg) of 18.8 per cent with an adjusted rate of 15.6 per cent, history of diabetes of 10.2 per cent, and obesity (body mass index > 30) of 27.7 per cent [significantly higher in women (34.4 per cent)], android obesity 36 per cent, smoking habits 21.5 per cent [significantly higher in men (61.4 per cent)]. With this profile of CVD risk factors, Tunisia must implement a national strategy of primary prevention and heart health promotion in addition to the efforts recently made in secondary prevention of some chronic diseases such as hypertension and diabetes.

Identification and diversity of functional centromere satellites in the wild rice species Oryza brachyantha.

PubMed

Yi, Chuandeng; Zhang, Wenli; Dai, Xibin; Li, Xing; Gong, Zhiyun; Zhou, Yong; Liang, Guohua; Gu, Minghong

2013-12-01

The centromere is a key chromosomal component for sister chromatid cohesion and is the site for kinetochore assembly and spindle fiber attachment, allowing each sister chromatid to faithfully segregate to each daughter cell during cell division. It is not clear what types of sequences act as functional centromeres and how centromere sequences are organized in Oryza brachyantha, an FF genome species. In this study, we found that the three classes of centromere-specific CentO-F satellites (CentO-F1, CentO-F2, and CentOF3) in O. brachyantha share no homology with the CentO satellites in Oryza sativa. The three classes of CentO-F satellites are all located within the chromosomal regions to which the spindle fibers attach and are characterized by megabase tandem arrays that are flanked by centromere-specific retrotransposons, CRR-F, in the O. brachyantha centromeres. Although these CentO-F satellites are quantitatively variable among 12 O. brachyantha centromeres, immunostaining with an antibody specific to CENH3 indicates that they are colocated with CENH3 in functional centromere regions. Our results demonstrate that the three classes of CentO-F satellites may be the major components of functional centromeres in O. brachyantha.

A core city problem: recruitment and retention of salaried physicians.

PubMed

Paxton, G S; Sbarbaro, J A; Nossaman, N

1975-03-01

The professional and personal characteristics of all physicians recruited into a large urban governmentally sponsored health system were evaluated and correlated to staff retention and loss. The results were tabulated for 84 physicians, approximately 90 per cent of the physician work force, over a three-year period. Eighty per cent resided in either Denver or the state of Colorado prior to entry. This is further reflected in a significant percentage being enrolled in the local medical school or training programs prior to entry. These facts suggest a possible source of manpower for beginning programs. Twenty-six per cent came from private practice, 32 per cent from the military and 14 per cent from the Public Health Service. The turnover rate averaged 6.2 per cent per year, with 4.4 per cent being initiated by the physician and 1.8 per cent leaving because of administrative pressure. Data from other studies are reviewed. Factors which appear to influence retention positively were residency training (pediatricians), sex (females), age (over 38) and those with team experience. These factors suggest directions as to the type of physician who, if recruited, tend to reduce turnover. The establishment of a group practice atmosphere with rewards for clinical skills and the offering of unusual specialty opportunities are proposed as positive factors in the retention of staff.

Short-term X-ray spectral variability of the quasar PDS 456 observed in a low-flux state

NASA Astrophysics Data System (ADS)

Matzeu, G. A.; Reeves, J. N.; Nardini, E.; Braito, V.; Costa, M. T.; Tombesi, F.; Gofford, J.

2016-05-01

We present a detailed analysis of a recent, 2013 Suzaku campaign on the nearby (z = 0.184) luminous (Lbol ˜ 1047 erg s-1) quasar PDS 456. This consisted of three observations, covering a total duration of ˜1 Ms and a net exposure of 455 ks. During these observations, the X-ray flux was unusually low, suppressed by a factor of >10 in the soft X-ray band when compared to previous observations. We investigated the broad-band continuum by constructing a spectral energy distribution (SED), making use of the optical/UV photometry and hard X-ray spectra from the later simultaneous XMM-Newton and NuSTAR campaign in 2014. The high-energy part of this low-flux SED cannot be accounted for by physically self-consistent accretion disc and corona models without attenuation by absorbing gas, which partially covers a substantial fraction of the line of sight towards the X-ray continuum. At least two layers of absorbing gas are required, of column density log (NH,low/cm-2) = 22.3 ± 0.1 and log (NH,high/cm-2) = 23.2 ± 0.1, with average line-of-sight covering factors of ˜80 per cent (with typical ˜5 per cent variations) and 60 per cent (±10-15 per cent), respectively. During these observations PDS 456 displays significant short-term X-ray spectral variability, on time-scales of ˜100 ks, which can be accounted for by variable covering of the absorbing gas along the line of sight. The partial covering absorber prefers an outflow velocity of v_pc = 0.25^{+0.01}_{-0.05} c at the >99.9 per cent confidence level over the case where vpc = 0. This is consistent with the velocity of the highly ionized outflow responsible for the blueshifted iron K absorption profile. We therefore suggest that the partial covering clouds could be the denser, or clumpy part of an inhomogeneous accretion disc wind. Finally estimates are placed upon the size-scale of the X-ray emission region from the source variability. The radial extent of the X-ray emitter is found to be of the order ˜15-20Rg, although the hard X-ray (>2 keV) emission may originate from a more compact or patchy corona of hot electrons, which is typically ˜6-8Rg in size.

PREPARATION OF HIGH-DENSITY, COMPACTIBLE THORIUM OXIDE PARTICLES

DOEpatents

McCorkle, K.H.; Kleinsteuber, A.T.; Schilling, C.E.; Dean, O.C.

1962-05-22

A method is given for preparing millimeter-size, highdensity thorium oxide particles suitable for fabrication into nuclear reactor feel elements by means of vibratory compaction. A thorium oxide gel containing 3.7 to 7 weight per cent residual volatile nitrate and water is prepared by drying a thorium oxide sol. The gel is then slowly heated to a temperature of about 450DEC, and the resulting gel fragments are calcined. The starting sol is prepared by repeated dispersion of oxalate-source thorium oxide in a nitrate system or by dispersion of steam-denitrated thorium oxide in water. (AEC)

The CentO satellite confers translational and rotational phasing on cenH3 nucleosomes in rice centromeres.

PubMed

Zhang, Tao; Talbert, Paul B; Zhang, Wenli; Wu, Yufeng; Yang, Zujun; Henikoff, Jorja G; Henikoff, Steven; Jiang, Jiming

2013-12-10

Plant and animal centromeres comprise megabases of highly repeated satellite sequences, yet centromere function can be specified epigenetically on single-copy DNA by the presence of nucleosomes containing a centromere-specific variant of histone H3 (cenH3). We determined the positions of cenH3 nucleosomes in rice (Oryza sativa), which has centromeres composed of both the 155-bp CentO satellite repeat and single-copy non-CentO sequences. We find that cenH3 nucleosomes protect 90-100 bp of DNA from micrococcal nuclease digestion, sufficient for only a single wrap of DNA around the cenH3 nucleosome core. cenH3 nucleosomes are translationally phased with 155-bp periodicity on CentO repeats, but not on non-CentO sequences. CentO repeats have an ∼10-bp periodicity in WW dinucleotides and in micrococcal nuclease cleavage, providing evidence for rotational phasing of cenH3 nucleosomes on CentO and suggesting that satellites evolve for translational and rotational stabilization of centromeric nucleosomes.

Occurrence of otitis media in children and assessment of treatment options.

PubMed

Nwokoye, N N; Egwari, L O; Olubi, O O

2015-08-01

Otitis media is a more frequent occurrence in children, and the disease may progress from an acute to chronic state if appropriate and timely intervention is not initiated. A total of 212 children aged 6 months to 10 years were examined and treated for otitis media, in a 13-month hospital-based study. Acute otitis media was diagnosed in 130 (61.3 per cent) of the patients. There were 82 (38.7 per cent) chronic suppurative otitis media cases. The incidence of acute otitis media and chronic suppurative otitis media in the first year of life was 54.6 per cent and 45.1 per cent respectively. Chronic suppurative otitis media patients were assigned to one of three treatment groups. Recovery occurred in 70.4 per cent of amoxicillin-treated patients, in 88.9 per cent of amoxicillin-clavulanic acid treated patients and in 96.4 per cent of culture and antibiotic sensitivity test patients. Relapses were seen only in the amoxicillin (five cases) and amoxicillin-clavulanic acid (two cases) groups. The success rate in patients treated with antibiotics makes this option mandatory for an established diagnosis.

Behavioral problems among patients in skilled nursing facilities.

PubMed Central

Zimmer, J G; Watson, N; Treat, A

1984-01-01

This survey of a 33 per cent random sample (1,139) of 3,456 patients in 42 skilled nursing facilities (SNFs) in upstate New York yielded 64.2 per cent with significant behavioral problems. Of these, 257 (22.6 per cent) of the total sample had what were defined as "serious" problems (i.e., excluding those with only impaired judgment and/or physical restraint orders). Details of the problem behaviors of this group, their previous history, current management, frequency of psychiatric consultation, and adequacy of documentation were analyzed. Median age was the same as the general SNF population, a slightly lower proportion was female, and, while 66.5 per cent had diagnoses indicating organic brain syndrome, very few had specific psychiatric diagnoses, and only 4.7 per cent had been admitted from a psychiatric facility. The attending physician had noted the behavioral problem in the record in only 9.7 per cent and had requested psychiatric consultation in 14.8 per cent of these "serious" cases. The need for more staff training in mental health care, and more physician and psychiatric consultative assistance are discussed. PMID:6476166

Patterns of meniscal tears associated with anterior cruciate ligament lesions in athletes.

PubMed

Binfield, P M; Maffulli, N; King, J B

1993-09-01

In this study, 400 clinically anterior cruciate ligament (ACL) deficient knees were arthroscoped and studied prospectively in the period January 1986 to April 1992. An ACL tear was always confirmed, and 41 per cent of these patients did not have an associated meniscal tear. In 30.25 per cent the lateral meniscus was torn; in 21.25 per cent the ACL tear was associated with a medial meniscus tear, and in the remaining 7 per cent both menisci were torn. The most frequently associated meniscal injury was the bucket handle tear of the medial meniscus (9 per cent), followed by the posterior horn tear of the lateral meniscus, which showed the same frequency as the ragged (or degenerated) tear of the lateral meniscus (6 per cent). The horizontal tear of the posterior part of the lateral meniscus showed a prevalence of 4.3 per cent. This picture is probably dependent on a secondary referral nature of the centre surveyed, in which the average time between injury and arthroscopy was 23.3 months.

Density functional theory for polymeric systems in 2D.

PubMed

Słyk, Edyta; Roth, Roland; Bryk, Paweł

2016-06-22

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

Centrifugal acceleration of the polar wind

NASA Technical Reports Server (NTRS)

Horwitz, J. L.; Ho, C. W.; Scarbro, H. D.; Wilson, G. R.; Moore, T. E.

1994-01-01

The effect of parallel ion acceleration associated with convection was first applied to energization of test particle polar ions by Cladis (1986). However, this effect is typically neglected in 'self-consistent' models of polar plasma outflow, apart from the fluid simulation by Swift (1990). Here we include approximations for this acceleration, which we broadly characterize as centrifugal in nature, in our time-dependent, semikinetic model of polar plasma outflow and describe the effects on the bulk parameter profiles and distribution functions of H+ and O+. For meridional convection across the pole the approximate parallel force along a polar magnetic field line may be written as F(sub cent, pole) = 1.5m(E(sub i))/B(sub i))squared (r(squared)/r(sup 3)(sub i)) where m is ion mass, r is geometric distance; and E(sub i), B(sub i) and r(sub i) refer to the electric and magnetic field magnitudes and geocentric distance at the ionosphere, respectively. For purely longitudinal convection along a constant L shell the parallel force is F(cent. long) = F(sub cent, pole)(1 - (r/(r(sub i)L))(sup 3/2)/(1 - 3r/(4 r(sub i)L))(sup 5/2). For high latitudes the difference between these two cases is relatively unimportant below approximately 5 R(sub E). We find that the steady state O+ bulk velocities and parallel temperatures strongly increase and decrease, respectively, with convection strength. In particular, the bulk velocities increase from near 0 km/s at 4000 km altitude to approximately 10 km/s at 5 R(sub E) geocentric distance for 50-mV/m ionospheric convection electric field. However, the centrifugal effect on the steady O+ density profiles depends on the exobase ion and electron temperatures: for low-base temperatures (T(sub i) = T(sub e) = 3000 K) the O+ density at high altitudes increases greatly with convection, while for higher base temperatures (T(sub i) = 5000 K, T(sub e) = 9000 K), the high-altitude O+ density decreases somewhat as convection is enhanced. The centrifugal force further has a pronounced effect on the escaping O+ flux, especially for cool exobase conditions; as referenced to the 4000-km altitude, the steady state O+ flux increases from 10(exp 5) ions/sq cm/s when the ionospheric convection field E(sub i) = 0 mV/m to approximately 10(exp 7) ions/sq cm/s when E(sub i) = 100 mV/m. The centrifugal effect also decreases the time scale for approach to steady-state. For example, in the plasma expansion for T(sub i) = T(sub e) = 3000 K, the O+ density at 7 R(sub E) reaches only 10(exp -7) of it final value approximately 1.5 hours after expansion onset for E(sub i) = 0. For meridional convection driven by E(sub i) = 50 mV/m, the density at the same time after initial injection is 30-50% of its asymptotic level. The centrifugal acceleration described here is a possible explanation for the large (up to approximately 10 km/s or more) o+ outflow velocities observed in the midlatitude polar magnetosphere with the Dynamics Explorer 1 and Akebono spacecraft.

The ATLAS3D project - I. A volume-limited sample of 260 nearby early-type galaxies: science goals and selection criteria

NASA Astrophysics Data System (ADS)

Cappellari, Michele; Emsellem, Eric; Krajnović, Davor; McDermid, Richard M.; Scott, Nicholas; Verdoes Kleijn, G. A.; Young, Lisa M.; Alatalo, Katherine; Bacon, R.; Blitz, Leo; Bois, Maxime; Bournaud, Frédéric; Bureau, M.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Khochfar, Sadegh; Kuntschner, Harald; Lablanche, Pierre-Yves; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Serra, Paolo; Weijmans, Anne-Marie

2011-05-01

The ATLAS3D project is a multiwavelength survey combined with a theoretical modelling effort. The observations span from the radio to the millimetre and optical, and provide multicolour imaging, two-dimensional kinematics of the atomic (H I), molecular (CO) and ionized gas (Hβ, [O III] and [N I]), together with the kinematics and population of the stars (Hβ, Fe5015 and Mg b), for a carefully selected, volume-limited (1.16 × 105 Mpc3) sample of 260 early-type (elliptical E and lenticular S0) galaxies (ETGs). The models include semi-analytic, N-body binary mergers and cosmological simulations of galaxy formation. Here we present the science goals for the project and introduce the galaxy sample and the selection criteria. The sample consists of nearby (D < 42 Mpc, |δ- 29°| < 35°, |b| > 15°) morphologically selected ETGs extracted from a parent sample of 871 galaxies (8 per cent E, 22 per cent S0 and 70 per cent spirals) brighter than MK < -21.5 mag (stellar mass M★≳ 6 ×109 M⊙). We analyse possible selection biases and we conclude that the parent sample is essentially complete and statistically representative of the nearby galaxy population. We present the size-luminosity relation for the spirals and ETGs and show that the ETGs in the ATLAS3D sample define a tight red sequence in a colour-magnitude diagram, with few objects in the transition from the blue cloud. We describe the strategy of the SAURON integral field observations and the extraction of the stellar kinematics with the pPXF method. We find typical 1σ errors of ΔV≈ 6 km s-1, Δσ≈ 7 km s-1, Δh3≈Δh4≈ 0.03 in the mean velocity, the velocity dispersion and Gauss-Hermite (GH) moments for galaxies with effective dispersion σe≳ 120 km s-1. For galaxies with lower σe (≈40 per cent of the sample) the GH moments are gradually penalized by pPXF towards zero to suppress the noise produced by the spectral undersampling and only V and σ can be measured. We give an overview of the characteristics of the other main data sets already available for our sample and of the ongoing modelling projects.

Morphological and behavioral limit of visual resolution in temperate (Hippocampus abdominalis) and tropical (Hippocampus taeniopterus) seahorses.

PubMed

Lee, Hie Rin; O'Brien, Keely M Bumsted

2011-07-01

Seahorses are visually guided feeders that prey upon small fast-moving crustaceans. Seahorse habitats range from clear tropical to turbid temperate waters. How are seahorse retinae specialized to mediate vision in these diverse environments? Most species of seahorse have a specialization in their retina associated with acute vision, the fovea. The purpose of this study was to characterize the fovea of temperate Hippocampus abdominalis and tropical H. taeniopterus seahorses and to investigate their theoretical and behavioral limits of visual resolution. Their foveae were identified and photoreceptor (PR) and ganglion cell (GC) densities determined throughout the retina and topographically mapped. The theoretical limit of visual resolution was calculated using formulas taking into account lens radius and either cone PR or GC densities. Visual resolution was determined behaviorally using reactive distance. Both species possess a rod-free convexiclivate fovea. PR and GC densities were highest along the foveal slope, with a density decrease within the foveal center. Outside the fovea, there was a gradual density decrease towards the periphery. The theoretically calculated visual resolution on the foveal slope was poorer for H. abdominalis (5.25 min of arc) compared with H. taeniopterus (4.63 min of arc) based on PR density. Using GC density, H. abdominalis (9.81 min of arc) had a lower resolution compared with H. taeniopterus (9.04 min of arc). Behaviorally, H. abdominalis had a resolution limit of 1090.64 min of arc, while H. taeniopterus was much smaller, 692.86 min of arc. Although both species possess a fovea and the distribution of PR and GC is similar, H. taeniopterus has higher PR and GC densities on the foveal slope and better theoretical and behaviorally measured visual resolution compared to H. abdominalis. These data indicate that seahorses have a well-developed acute visual system, and tropical seahorses have higher visual resolution compared to temperate seahorses.

Early assembly of the most massive galaxies.

PubMed

Collins, Chris A; Stott, John P; Hilton, Matt; Kay, Scott T; Stanford, S Adam; Davidson, Michael; Hosmer, Mark; Hoyle, Ben; Liddle, Andrew; Lloyd-Davies, Ed; Mann, Robert G; Mehrtens, Nicola; Miller, Christopher J; Nichol, Robert C; Romer, A Kathy; Sahlén, Martin; Viana, Pedro T P; West, Michael J

2009-04-02

The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in sub-galactic-sized building blocks called haloes which are subsequently assembled into galaxies. However, exactly when this assembly takes place is a matter of some debate. Here we report that the stellar masses of brightest cluster galaxies, which are the most luminous objects emitting stellar light, some 9 billion years ago are not significantly different from their stellar masses today. Brightest cluster galaxies are almost fully assembled 4-5 billion years after the Big Bang, having grown to more than 90 per cent of their final stellar mass by this time. Our data conflict with the most recent galaxy formation models based on the largest simulations of dark-matter halo development. These models predict protracted formation of brightest cluster galaxies over a Hubble time, with only 22 per cent of the stellar mass assembled at the epoch probed by our sample. Our findings suggest a new picture in which brightest cluster galaxies experience an early period of rapid growth rather than prolonged hierarchical assembly.

Plant genotypic diversity reduces the rate of consumer resource utilization

PubMed Central

McArt, Scott H.; Thaler, Jennifer S.

2013-01-01

While plant species diversity can reduce herbivore densities and herbivory, little is known regarding how plant genotypic diversity alters resource utilization by herbivores. Here, we show that an invasive folivore—the Japanese beetle (Popillia japonica)—increases 28 per cent in abundance, but consumes 24 per cent less foliage in genotypic polycultures compared with monocultures of the common evening primrose (Oenothera biennis). We found strong complementarity for reduced herbivore damage among plant genotypes growing in polycultures and a weak dominance effect of particularly resistant genotypes. Sequential feeding by P. japonica on different genotypes from polycultures resulted in reduced consumption compared with feeding on different plants of the same genotype from monocultures. Thus, diet mixing among plant genotypes reduced herbivore consumption efficiency. Despite positive complementarity driving an increase in fruit production in polycultures, we observed a trade-off between complementarity for increased plant productivity and resistance to herbivory, suggesting costs in the complementary use of resources by plant genotypes may manifest across trophic levels. These results elucidate mechanisms for how plant genotypic diversity simultaneously alters resource utilization by both producers and consumers, and show that population genotypic diversity can increase the resistance of a native plant to an invasive herbivore. PMID:23658201

Plant genotypic diversity reduces the rate of consumer resource utilization.

PubMed

McArt, Scott H; Thaler, Jennifer S

2013-07-07

While plant species diversity can reduce herbivore densities and herbivory, little is known regarding how plant genotypic diversity alters resource utilization by herbivores. Here, we show that an invasive folivore--the Japanese beetle (Popillia japonica)--increases 28 per cent in abundance, but consumes 24 per cent less foliage in genotypic polycultures compared with monocultures of the common evening primrose (Oenothera biennis). We found strong complementarity for reduced herbivore damage among plant genotypes growing in polycultures and a weak dominance effect of particularly resistant genotypes. Sequential feeding by P. japonica on different genotypes from polycultures resulted in reduced consumption compared with feeding on different plants of the same genotype from monocultures. Thus, diet mixing among plant genotypes reduced herbivore consumption efficiency. Despite positive complementarity driving an increase in fruit production in polycultures, we observed a trade-off between complementarity for increased plant productivity and resistance to herbivory, suggesting costs in the complementary use of resources by plant genotypes may manifest across trophic levels. These results elucidate mechanisms for how plant genotypic diversity simultaneously alters resource utilization by both producers and consumers, and show that population genotypic diversity can increase the resistance of a native plant to an invasive herbivore.

Toxic effects of theobromine on mature and immature male rabbits.

PubMed

Soffietti, M G; Nebbia, C; Valenza, F; Amedeo, S; Re, G

1989-01-01

Mature and immature male rabbits were fed for 120 and 20 days, respectively, a commercial diet containing theobromine in amounts of 0, 0.5, 1 and 1.5 per cent. Clinical, haematological, histopathological and histoenzymological examinations were performed. Mortality, which appeared dose- and time-related, was severe and rapid, mostly in the 1 and 1.5 per cent groups and was attributed to cardiac failure. Theobromine administration resulted in marked changes in thymus and testes and the severity of lesions appeared to be related to the amounts of the ingested methylxanthine. The earliest thymic alterations in immature rabbits consisted of a blurring of demarcation between cortex and medulla accompanied, in the more advanced stages, by a decreased lymphocyte density. Similar lesions were observed in mature animals which had died in the earlier phase of the study. Testicular alterations ranged from vacuolation of spermatids and spermatocytes to multinucleated cell formation and oligospermia or aspermia with extensive degeneration of tubule cells. Some necrotic and post-necrotic myocardial foci were also recorded. The increase in testicular activity of beta-glucuronidase in immature rabbits compared to the untreated animals provided further evidence of an early theobromine-induced damage of the testes.

Hydrodynamical simulations of coupled and uncoupled quintessence models - II. Galaxy clusters

NASA Astrophysics Data System (ADS)

Carlesi, Edoardo; Knebe, Alexander; Lewis, Geraint F.; Yepes, Gustavo

2014-04-01

We study the z = 0 properties of clusters (and large groups) of galaxies within the context of interacting and non-interacting quintessence cosmological models, using a series of adiabatic SPH simulations. Initially, we examine the average properties of groups and clusters, quantifying their differences in ΛCold Dark Matter (ΛCDM), uncoupled Dark Energy (uDE) and coupled Dark Energy (cDE) cosmologies. In particular, we focus upon radial profiles of the gas density, temperature and pressure, and we also investigate how the standard hydrodynamic equilibrium hypothesis holds in quintessence cosmologies. While we are able to confirm previous results about the distribution of baryons, we also find that the main discrepancy (with differences up to 20 per cent) can be seen in cluster pressure profiles. We then switch attention to individual structures, mapping each halo in quintessence cosmology to its ΛCDM counterpart. We are able to identify a series of small correlations between the coupling in the dark sector and halo spin, triaxiality and virialization ratio. When looking at spin and virialization of dark matter haloes, we find a weak (5 per cent) but systematic deviation in fifth force scenarios from ΛCDM.

Total lung capacity, residual volume and predicted residual volume in a densitometric study of older men.

PubMed Central

Latin, R W; Ruhling, R O

1986-01-01

Results of investigations using various lung volumes for hydrostatic weighing determinations (HWD) appear to be inconclusive. Often, these lung volumes are predicted and not clinically determined. For this reason, total lung capacity (TLC), a measured residual volume (RV), and a predicted residual volume (PRV) were used during HWDs to compare the techniques. Twenty-five older men, 56 to 70 years (means +/- 62.1 + 4.2 years) performed HWDs at RV (10 trials) and at TLC (3-5 trials). Values for body density and fat free mass were not significantly different between RV and TLC; both values were, however, significantly different from those derived using PRV. There were statistically significant differences (p less than 0.05) between all 3 per cent body fat values but the 1.1 per cent difference between TLC and RV may not be physiologically important. It was concluded that TLC and RV may be used comparably during HWDs, but a PRV may produce significantly different values. Since HWD at TLC is easily performed and circumvents the difficulties associated with the RV technique, it may be the preferred method for older subjects. PMID:3730758

Heritage or Hate? A Pedagogical Guide to the Confederate Flag in Post-Race America

ERIC Educational Resources Information Center

Lippard, Cameron D.

2017-01-01

The Confederate flag has been a hotly debated symbol of heritage or hate in the United States. In 2015, 54 per cent of Americans polled saw the flag as a symbol of 'Southern pride' whereas 34 per cent saw it as racist. However, 27 per cent of Whites compared to 69 per cent of Blacks saw the flag as racist. In this article, I suggest how…

Comparison of Battlefield-expedient Topical Antimicrobial Agents for the Prevention of Burn Wound Sepsis in a Rat Model

DTIC Science & Technology

2005-08-01

Bertek Pharmaceuticals, Morgantown WV); 5% mafenide hydrochloride solution (MHS, Sigma, St. Louis, MO), and 4% chlorhexidine digluconate solution...silver sulphadiazine 1 per cent, silver sulphadiazine 1 per cent plus chlorhexidine digluconate 0.2 per cent and mafenide acetate 8.5 per cent for...Comparison of silver sulfadiazine 1% with chlorhexidine digluconate 0.2% to silver sulfadiazine 1% alone in the prophylactic topical anti- bacterial treatment

Qualitative Research in the CJA/RCV: An 18-Year Analysis (1995-2012).

PubMed

Humble, Áine M; Green, Maureen

2016-03-01

Some researchers have suggested that qualitative research is increasing in the gerontology field, but little systematic analysis has tested this assertion. Using the Canadian Journal on Aging/La Revue canadienne du vieillissement as a case study, we analysed articles reporting on original research from 1995 to 2012. One in four articles were qualitative, and results in three-year intervals show a clear increase in qualitative research findings during this 18-year time frame: (a) 1995-1997: 10 per cent; (b) 1998-2000: 19 per cent; (c) 2001-2003: 25 per cent; (d) 2004-2006: 25 per cent; (e) 2007-2009: 29 per cent; and (f) 2010-2012: 43 per cent. In all time intervals (with the exception of 2004-2006), French language articles were more likely to use a qualitative research design compared to English language articles. Topics, methodologies, and data collection strategies are also discussed.

Sun tanning-related burns--a 3-year experience.

PubMed

Piccolo-Lobo, M S; Piccolo, N S; Piccolo-Daher, M T; Cardoso, V M

1992-04-01

A retrospective study has analyzed 562 sun-related burns out of 19,643 patients treated at our institution from 1 March 1988 to 28 February 1991. These patients were analysed according to sex, age, burn area, mode and length of treatment and outcome. Females, mainly adults, represented 60.8 per cent of all patients presenting burned due to sun bathing. There is a marked seasonal incidence, proportionally constant throughout these 3 years. The main causes of injury were sun only (36.7 per cent), sun plus fig leaf 'tea' tanning lotion (17.7 per cent) and lemon juice (17.7 per cent). Healing to normal skin appearance was achieved in 99.1 per cent, 0.7 per cent healed with scarring and one patient died due to massive sepsis. The effect of sunlight on skin and the process of 'sunburn' when using homemade plant-derived tanning lotions containing substances which can induce a photodermatitis reaction is also discussed.

Smoking in hotels: prevalence, and opinions about restrictions.

PubMed

Semmonds, A; Bailey, K; Bentley, S; Chase, V; Fernando, S; Guruge, A; King, M; Tan, O M; Walsh, R

1995-02-01

Exposure to high levels of environmental tobacco smoke can occur in hotels. Controversy exists about smoking regulation on licensed premises. This survey of 138 people attending one of three Newcastle hotels during 1993 found that 57 per cent of respondents were nonsmokers. Fifty-eight per cent (95 per cent confidence interval (CI) 50 to 66 per cent) of respondents in these hotels believed their health was being adversely affected by other people's smoke in the hotel. Seventy per cent (CI 62 to 78 per cent), including half the smokers, were in favour of restriction of smoking in the hotels. Most preferred the establishment of smoke-free areas to the introduction of total smoking bans in hotels. The failure of hotels to regulate smoking suggests that a legislative approach is required. The case for legislation would be strengthened by a larger study elsewhere in Australia.

Improved compaction of ZnO nano-powder triggered by the presence of acetate and its effect on sintering.

PubMed

Dargatz, Benjamin; Gonzalez-Julian, Jesus; Guillon, Olivier

2015-04-01

The retention of nanocrystallinity in dense ceramic materials is still a challenge, even with the application of external pressure during sintering. The compaction behavior of high purity and acetate enriched zinc oxide (ZnO) nano-powders was investigated. It was found that acetate in combination with water plays a key role during the compaction into green bodies at moderate temperatures. Application of constant pressure resulted in a homogeneous green body with superior packing density (86% of theoretical value) at moderate temperature (85 °C) in the presence of water. In contrast, no improvement in density could be achieved if pure ZnO powder was used. This compaction behavior offers superior packing of the particles, resulting in a high relative density of the consolidated compact with negligible coarsening. Dissolution accompanying creep diffusion based matter transport is suggested to strongly support reorientation of ZnO particles towards densities beyond the theoretical limit for packing of ideal monosized spheres. Finally, the sintering trajectory reveals that grain growth is retarded compared to conventional processing up to 90% of theoretical density. Moreover, nearly no radial shrinkage was observed after sinter-forging for bodies performed with this advanced processing method.

Improved compaction of ZnO nano-powder triggered by the presence of acetate and its effect on sintering

PubMed Central

Gonzalez-Julian, Jesus; Guillon, Olivier

2015-01-01

The retention of nanocrystallinity in dense ceramic materials is still a challenge, even with the application of external pressure during sintering. The compaction behavior of high purity and acetate enriched zinc oxide (ZnO) nano-powders was investigated. It was found that acetate in combination with water plays a key role during the compaction into green bodies at moderate temperatures. Application of constant pressure resulted in a homogeneous green body with superior packing density (86% of theoretical value) at moderate temperature (85 °C) in the presence of water. In contrast, no improvement in density could be achieved if pure ZnO powder was used. This compaction behavior offers superior packing of the particles, resulting in a high relative density of the consolidated compact with negligible coarsening. Dissolution accompanying creep diffusion based matter transport is suggested to strongly support reorientation of ZnO particles towards densities beyond the theoretical limit for packing of ideal monosized spheres. Finally, the sintering trajectory reveals that grain growth is retarded compared to conventional processing up to 90% of theoretical density. Moreover, nearly no radial shrinkage was observed after sinter-forging for bodies performed with this advanced processing method. PMID:27877777

Simulating the assembly of galaxies at redshifts z = 6-12

NASA Astrophysics Data System (ADS)

Dayal, Pratika; Dunlop, James S.; Maio, Umberto; Ciardi, Benedetta

2013-09-01

We use state-of-the-art simulations to explore the physical evolution of galaxies in the first billion years of cosmic time. First, we demonstrate that our model reproduces the basic statistical properties of the observed Lyman-break galaxy (LBG) population at z = 6-8, including the evolving ultraviolet (UV) luminosity function (LF), the stellar mass density (SMD) and the average specific star-formation rates (sSFRs) of LBGs with MUV < -18 (AB mag). Encouraged by this success we present predictions for the behaviour of fainter LBGs extending down to MUV ≃ -15 (as will be probed with the James Webb Space Telescope) and have interrogated our simulations to try to gain insight into the physical drivers of the observed population evolution. We find that mass growth due to star formation in the mass-dominant progenitor builds up about 90 per cent of the total z ˜ 6 LBG stellar mass, dominating over the mass contributed by merging throughout this era. Our simulation suggests that the apparent `luminosity evolution' depends on the luminosity range probed: the steady brightening of the bright end of the LF is driven primarily by genuine physical luminosity evolution and arises due to a fairly steady increase in the UV luminosity (and hence star-formation rates) in the most massive LBGs; for example the progenitors of the z ≃ 6 galaxies with MUV < -18.5 comprised ≃90 per cent of the galaxies with MUV < -18 at z ≃ 7 and ≃75 per cent at z ≃ 8. However, at fainter luminosities the situation is more complex, due in part to the more stochastic star-formation histories of lower mass objects; the progenitors of a significant fraction of z ≃ 6 LBGs with MUV > -18 were in fact brighter at z ≃ 7 (and even at z ≃ 8) despite obviously being less massive at earlier times. At this end, the evolution of the UV LF involves a mix of positive and negative luminosity evolution (as low-mass galaxies temporarily brighten and then fade) coupled with both positive and negative density evolution (as new low-mass galaxies form, and other low-mass galaxies are consumed by merging). We also predict that the average sSFR of LBGs should rise from sSFR ≃ 4.5 Gyr- 1 at z ≃ 6 to sSFR ≃ 11 Gyr- 1 by z ≃ 9.

Energy density of anchovy Engraulis encrasicolus in the Bay of Biscay.

PubMed

Dubreuil, J; Petitgas, P

2009-02-01

The energy density (E(D)) of anchovy Engraulis encrasicolus in the Bay of Biscay was determined by direct calorimetry and its evolution with size, age and season was investigated. The water content and energy density varied seasonally following opposite trends. The E(D) g(-1) of wet mass (M(W)) was highest at the end of the feeding season (autumn: c. 8 kJ g(-1)M(W)) and lowest in late winter (c. 6 kJ g(-1)M(W)). In winter, the fish lost mass, which was partially replaced by water, and the energy density decreased. These variations in water content and organic matter content may have implications on the buoyancy of the fish. The water content was the major driver of the energy density variations for a M(W) basis. A significant linear relationship was established between E(D) g(-1) (y) and the per cent dry mass (M(D); x): y =-4.937 + 0.411x. In the light of the current literature, this relationship seemed to be not only species specific but also ecosystem specific. Calibration and validation of fish bioenergetics models require energy content measurements on fish samples collected at sea. The present study provides a first reference for the energetics of E. encrasicolus in the Bay of Biscay.

SCF-Xα-SW electron densities with the overlapping sphere approximation

NASA Astrophysics Data System (ADS)

McMaster, Blair N.; Smith, Vedene H., Jr.; Salahub, Dennis R.

Self consistent field-Xα-scattered wave (SCF-Xα-SW) calculations have been performed for a series of eight first and second row homonuclear diatomic molecules using both the touching (TS) and 25 per cent overlapping sphere (OS) versions. The OS deformation density maps exhibit much better quantitative agreement with those from other Xα methods, which do not employ the spherical muffin-tin (MT) potential approximation, than do the TS maps. The OS version thus compensates very effectively for the errors involved in the MT approximation in computing electron densities. A detailed comparison between the TS- and OS-Xα-SW orbitals reveals that the reasons for this improvement are surprisingly specific. The dominant effect of the OS approximation is to increase substantially the electron density near the midpoint of bonding σ orbitals, with a consequent reduction of the density behind the atoms. A similar effect occurs for the bonding π orbitals but is less pronounced. These effects are due to a change in hybridization of the orbitals, with the OS approximation increasing the proportion of the subdominant partial waves and hence changing the shapes of the orbitals. It is this increased orbital polarization which so effectively compensates for the lack of (non-spherically symmetric) polarization components in the MT potential, when overlapping spheres are used.

Accuracy of vision technicians in screening ocular pathology at rural vision centres of southern India.

PubMed

Suram, Vasantha; Addepalli, Uday Kumar; Krishnaiah, Sannapaneni; Kovai, Vilas; Khanna, Rohit C

2016-03-01

There is paucity of data on the inter-observer agreement and diagnostic accuracy between a primary-care technician (vision technician) and an ophthalmologist. Hence, the current study was conducted to assess the accuracy of vision technicians, to screen potentially sight-threatening ocular conditions at rural vision centres of southern India and their agreement with an ophthalmologist. In July to August 2010, patients presenting to seven vision centres in Adilabad district (Andhra Pradesh) were selected and screened in a masked manner by seven vision technicians followed by an examination by a consultant ophthalmologist. Agreement was assessed between vision technicians and the ophthalmologist for screening of potential sight-threatening ocular conditions and decisions for referral. The ophthalmologist's findings were considered as the reference standard. Two hundred and seventy-nine patients were enrolled at seven vision centres with a mean age of 32.9 ± 21.8 years. Agreement for screening of ocular pathology was 0.82 (95 per cent CI, 0.8-0.83). There was excellent agreement for cataract (0.97; 95 per cent CI, 0.93-1), refractive error (0.98; 95 per cent CI, 0.96-1), corneal pathology (1.0; 95 per cent CI, 1.0-1.0) and other anterior segment pathology (0.95; 95 per cent CI, 0.9-1); the agreement was moderate to fair for detection of glaucoma suspects (0.43; 95 per cent CI, 0.28-0.60) and retinal pathology (0.39; 95 per cent CI, 0.14-0.63). Sensitivity for screening of anterior segment pathology was 94.6-100 per cent. There was a fair to moderate sensitivity for glaucoma suspect; 35.6 per cent (95 per cent CI, 21.9-51.2) and retinal pathology 26.3 per cent (95 per cent CI, 9.2-51.2). Specificity for screening of ocular pathology was 98.2 to 100 per cent. The kappa (κ) agreement for referral for any pathology was 0.82 (0.8-0.83) CONCLUSION: As there is good agreement between the vision technicians and the ophthalmologist for screening and referral of anterior segment pathology but moderate to fair for glaucoma suspects and retinal pathology, vision technicians would be a good resource at the primary level to screen for anterior segment pathology; however, they may need further training to detect posterior segment pathology. © 2016 Optometry Australia.

Kangaroo mother care: a randomized controlled trial on effectiveness of early kangaroo mother care for the low birthweight infants in Addis Ababa, Ethiopia.

PubMed

Worku, Bogale; Kassie, Assaye

2005-04-01

A randomized controlled trial was conducted over a 1-year period (November 2001-November 2002) in Addis Ababa to study the effectiveness of early Kangaroo mother care before stabilization of low birthweight infants as compared with the conventional method of care. There were 259 babies weighing less than 2000 g during the study period and a total of 123 (47.5 per cent) low birthweight infants were included in to the study. Sixty-two infants were enrolled as Kangaroo Mother Care (KMC) and the remaining 61 were Conventional Method of Care (CMC) cases. The demographic and socioeconomic characteristics for both groups were comparable. The mean age at the time of enrollment was 10 and 9.8 h for KMC and CMC, respectively (p>0.05 with 95 per cent confidence interval). The mean birthweight was 1514.8 g (range 1000-1900 g) for KMC and 1471.8 g (range 930-1900 g) for CMC (p>0.05 with 95 per cent CI) and the mean gestational age was 32.42 and 31.59 weeks for KMC and CMC cases, respectively. Fifty-eight per cent of KMC and 52 per cent of CMC cases were on i.v. fluid. Twenty-one of 62 (34 per cent) of KMC and 23/61 (37 per cent) of CMC babies were on oxygen through nasopharyngeal catheter. The mean age at exit from the study was 4.6 days for KMC and 5.4 days for CMC. Ninety-one per cent and 88 per cent of babies in KMC and CMC were discharged from the study in the first 7 days of life, respectively. The study showed that 14/62 (22.5 per cent) of KMC vs. 24/63 (38 per cent) CMC babies died during the study (p<0.05 and CI of 95 per cent.) The majority of deaths occurred during the first 12 h of life. Survival for the preterm low birthweight infants was remarkably better for the early kangaroo mother care group than the babies in the conventional method of care in the first 12 h and there after. More than 95 per cent of mothers reported that they were happy to care for their low birthweight babies using the early Kangaroo mother method. It was recommended to study the feasibility and effectiveness of Kangaroo mother care at the community level.

A temperate rocky super-Earth transiting a nearby cool star

NASA Astrophysics Data System (ADS)

Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Bonfils, Xavier; Astudillo-Defru, Nicola; Haywood, Raphaëlle D.; Berta-Thompson, Zachory K.; Newton, Elisabeth R.; Rodriguez, Joseph E.; Winters, Jennifer G.; Tan, Thiam-Guan; Almenara, Jose-Manuel; Bouchy, François; Delfosse, Xavier; Forveille, Thierry; Lovis, Christophe; Murgas, Felipe; Pepe, Francesco; Santos, Nuno C.; Udry, Stephane; Wünsche, Anaël; Esquerdo, Gilbert A.; Latham, David W.; Dressing, Courtney D.

2017-04-01

M dwarf stars, which have masses less than 60 per cent that of the Sun, make up 75 per cent of the population of the stars in the Galaxy. The atmospheres of orbiting Earth-sized planets are observationally accessible via transmission spectroscopy when the planets pass in front of these stars. Statistical results suggest that the nearest transiting Earth-sized planet in the liquid-water, habitable zone of an M dwarf star is probably around 10.5 parsecs away. A temperate planet has been discovered orbiting Proxima Centauri, the closest M dwarf, but it probably does not transit and its true mass is unknown. Seven Earth-sized planets transit the very low-mass star TRAPPIST-1, which is 12 parsecs away, but their masses and, particularly, their densities are poorly constrained. Here we report observations of LHS 1140b, a planet with a radius of 1.4 Earth radii transiting a small, cool star (LHS 1140) 12 parsecs away. We measure the mass of the planet to be 6.6 times that of Earth, consistent with a rocky bulk composition. LHS 1140b receives an insolation of 0.46 times that of Earth, placing it within the liquid-water, habitable zone. With 90 per cent confidence, we place an upper limit on the orbital eccentricity of 0.29. The circular orbit is unlikely to be the result of tides and therefore was probably present at formation. Given its large surface gravity and cool insolation, the planet may have retained its atmosphere despite the greater luminosity (compared to the present-day) of its host star in its youth. Because LHS 1140 is nearby, telescopes currently under construction might be able to search for specific atmospheric gases in the future.

The JCMT Gould Belt Survey: evidence for radiative heating and contamination in the W40 complex

NASA Astrophysics Data System (ADS)

Rumble, D.; Hatchell, J.; Pattle, K.; Kirk, H.; Wilson, T.; Buckle, J.; Berry, D. S.; Broekhoven-Fiene, H.; Currie, M. J.; Fich, M.; Jenness, T.; Johnstone, D.; Mottram, J. C.; Nutter, D.; Pineda, J. E.; Quinn, C.; Salji, C.; Tisi, S.; Walker-Smith, S.; di Francesco, J.; Hogerheijde, M. R.; Ward-Thompson, D.; Bastien, P.; Bresnahan, D.; Butner, H.; Chen, M.; Chrysostomou, A.; Coude, S.; Davis, C. J.; Drabek-Maunder, E.; Duarte-Cabral, A.; Fiege, J.; Friberg, P.; Friesen, R.; Fuller, G. A.; Graves, S.; Greaves, J.; Gregson, J.; Holland, W.; Joncas, G.; Kirk, J. M.; Knee, L. B. G.; Mairs, S.; Marsh, K.; Matthews, B. C.; Moriarty-Schieven, G.; Mowat, C.; Rawlings, J.; Richer, J.; Robertson, D.; Rosolowsky, E.; Sadavoy, S.; Thomas, H.; Tothill, N.; Viti, S.; White, G. J.; Wouterloot, J.; Yates, J.; Zhu, M.

2016-08-01

We present SCUBA-2 450 μm and 850 μm observations of the W40 complex in the Serpens-Aquila region as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) of nearby star-forming regions. We investigate radiative heating by constructing temperature maps from the ratio of SCUBA-2 fluxes using a fixed dust opacity spectral index, β = 1.8, and a beam convolution kernel to achieve a common 14.8 arcsec resolution. We identify 82 clumps ranging between 10 and 36 K with a mean temperature of 20 ± 3 K. Clump temperature is strongly correlated with proximity to the external OB association and there is no evidence that the embedded protostars significantly heat the dust. We identify 31 clumps that have cores with densities greater than 105cm-3. 13 of these cores contain embedded Class 0/I protostars. Many cores are associated with bright-rimmed clouds seen in Herschel 70 μm images. From JCMT HARP observations of the 12CO 3-2 line, we find contamination of the 850 μm band of up to 20 per cent. We investigate the free-free contribution to SCUBA-2 bands from large-scale and ultracompact H II regions using archival VLA data and find the contribution is limited to individual stars, accounting for 9 per cent of flux per beam at 450 μm or 12 per cent at 850 μm in these cases. We conclude that radiative heating has potentially influenced the formation of stars in the Dust Arc sub-region, favouring Jeans stable clouds in the warm east and fragmentation in the cool west.

Characterization of polarimetric and total intensity behaviour of a complete sample of PACO radio sources in the radio bands

NASA Astrophysics Data System (ADS)

Galluzzi, V.; Massardi, M.; Bonaldi, A.; Casasola, V.; Gregorini, L.; Trombetti, T.; Burigana, C.; Bonato, M.; De Zotti, G.; Ricci, R.; Stevens, J.; Ekers, R. D.; Bonavera, L.; di Serego Alighieri, S.; Liuzzo, E.; López-Caniego, M.; Paladino, R.; Toffolatti, L.; Tucci, M.; Callingham, J. R.

2018-03-01

We present high sensitivity (σP ≃ 0.6 mJy) polarimetric observations in seven bands, from 2.1 to 38 GHz, of a complete sample of 104 compact extragalactic radio sources brighter than 200 mJy at 20 GHz. Polarization measurements in six bands, in the range 5.5-38 GHz, for 53 of these objects were reported by Galluzzi et al. We have added new measurements in the same six bands for another 51 sources and measurements at 2.1 GHz for the full sample of 104 sources. Also, the previous measurements at 18, 24, 33, and 38 GHz were re-calibrated using the updated model for the flux density absolute calibrator, PKS1934-638, not available for the earlier analysis. The observations, carried out with the Australia Telescope Compact Array, achieved a 90 per cent detection rate (at 5σ) in polarization. 89 of our sources have a counterpart in the 72-231 MHz GLEAM (GaLactic and Extragalactic All-sky Murchison Widefield Array) survey, providing an unparalleled spectral coverage of 2.7 decades of frequency for these sources. While the total intensity data from 5.5 to 38 GHz could be interpreted in terms of single component emission, a joint analysis of more extended total intensity spectra presented here, and of the polarization spectra, reveals that over 90 per cent of our sources show clear indications of at least two emission components. We interpret this as an evidence of recurrent activity. Our high sensitivity polarimetry has allowed a 5σ detection of the weak circular polarization for ˜ 38 per cent of the data set, and a deeper estimate of 20 GHz polarization source counts than has been possible so far.

Identifying the progenitors of present-day early-type galaxies in observational surveys: correcting `progenitor bias' using the Horizon-AGN simulation

NASA Astrophysics Data System (ADS)

Martin, G.; Kaviraj, S.; Devriendt, J. E. G.; Dubois, Y.; Pichon, C.; Laigle, C.

2018-03-01

As endpoints of the hierarchical mass-assembly process, the stellar populations of local early-type galaxies encode the assembly history of galaxies over cosmic time. We use Horizon-AGN, a cosmological hydrodynamical simulation, to study the merger histories of local early-type galaxies and track how the morphological mix of their progenitors evolves over time. We provide a framework for alleviating `progenitor bias' - the bias that occurs if one uses only early-type galaxies to study the progenitor population. Early types attain their final morphology at relatively early epochs - by z ˜ 1, around 60 per cent of today's early types have had their last significant merger. At all redshifts, the majority of mergers have one late-type progenitor, with late-late mergers dominating at z > 1.5 and early-early mergers becoming significant only at z < 0.5. Progenitor bias is severe at all but the lowest redshifts - e.g. at z ˜ 0.6, less than 50 per cent of the stellar mass in today's early types is actually in progenitors with early-type morphology, while, at z ˜ 2, studying only early types misses almost all (80 per cent) of the stellar mass that eventually ends up in local early-type systems. At high redshift, almost all massive late-type galaxies, regardless of their local environment or star formation rate, are progenitors of local early-type galaxies, as are lower mass (M⋆ < 1010.5 M_{⊙}) late-types as long as they reside in high-density environments. In this new era of large observational surveys (e.g. LSST, JWST), this study provides a framework for studying how today's early-type galaxies have been built up over cosmic time.

A temperate rocky super-Earth transiting a nearby cool star.

PubMed

Dittmann, Jason A; Irwin, Jonathan M; Charbonneau, David; Bonfils, Xavier; Astudillo-Defru, Nicola; Haywood, Raphaëlle D; Berta-Thompson, Zachory K; Newton, Elisabeth R; Rodriguez, Joseph E; Winters, Jennifer G; Tan, Thiam-Guan; Almenara, Jose-Manuel; Bouchy, François; Delfosse, Xavier; Forveille, Thierry; Lovis, Christophe; Murgas, Felipe; Pepe, Francesco; Santos, Nuno C; Udry, Stephane; Wünsche, Anaël; Esquerdo, Gilbert A; Latham, David W; Dressing, Courtney D

2017-04-19

M dwarf stars, which have masses less than 60 per cent that of the Sun, make up 75 per cent of the population of the stars in the Galaxy. The atmospheres of orbiting Earth-sized planets are observationally accessible via transmission spectroscopy when the planets pass in front of these stars. Statistical results suggest that the nearest transiting Earth-sized planet in the liquid-water, habitable zone of an M dwarf star is probably around 10.5 parsecs away. A temperate planet has been discovered orbiting Proxima Centauri, the closest M dwarf, but it probably does not transit and its true mass is unknown. Seven Earth-sized planets transit the very low-mass star TRAPPIST-1, which is 12 parsecs away, but their masses and, particularly, their densities are poorly constrained. Here we report observations of LHS 1140b, a planet with a radius of 1.4 Earth radii transiting a small, cool star (LHS 1140) 12 parsecs away. We measure the mass of the planet to be 6.6 times that of Earth, consistent with a rocky bulk composition. LHS 1140b receives an insolation of 0.46 times that of Earth, placing it within the liquid-water, habitable zone. With 90 per cent confidence, we place an upper limit on the orbital eccentricity of 0.29. The circular orbit is unlikely to be the result of tides and therefore was probably present at formation. Given its large surface gravity and cool insolation, the planet may have retained its atmosphere despite the greater luminosity (compared to the present-day) of its host star in its youth. Because LHS 1140 is nearby, telescopes currently under construction might be able to search for specific atmospheric gases in the future.

H-ATLAS/GAMA: the nature and characteristics of optically red galaxies detected at submillimetre wavelengths

NASA Astrophysics Data System (ADS)

Dariush, A.; Dib, S.; Hony, S.; Smith, D. J. B.; Zhukovska, S.; Dunne, L.; Eales, S.; Andrae, E.; Baes, M.; Baldry, I.; Bauer, A.; Bland-Hawthorn, J.; Brough, S.; Bourne, N.; Cava, A.; Clements, D.; Cluver, M.; Cooray, A.; De Zotti, G.; Driver, S.; Grootes, M. W.; Hopkins, A. M.; Hopwood, R.; Kaviraj, S.; Kelvin, L.; Lara-Lopez, M. A.; Liske, J.; Loveday, J.; Maddox, S.; Madore, B.; Michałowski, M. J.; Pearson, C.; Popescu, C.; Robotham, A.; Rowlands, K.; Seibert, M.; Shabani, F.; Smith, M. W. L.; Taylor, E. N.; Tuffs, R.; Valiante, E.; Virdee, J. S.

2016-02-01

We combine Herschel/SPIRE submillimetre (submm) observations with existing multiwavelength data to investigate the characteristics of low-redshift, optically red galaxies detected in submm bands. We select a sample of galaxies in the redshift range 0.01 ≤ z ≤ 0.2, having >5σ detections in the SPIRE 250 μm submm waveband. Sources are then divided into two sub-samples of red and blue galaxies, based on their UV-optical colours. Galaxies in the red sample account for ≈4.2 per cent of the total number of sources with stellar masses M* ≳ 1010 M⊙. Following visual classification of the red galaxies, we find that ≳30 per cent of them are early-type galaxies and ≳40 per cent are spirals. The colour of the red-spiral galaxies could be the result of their highly inclined orientation and/or a strong contribution of the old stellar population. It is found that irrespective of their morphological types, red and blue sources occupy environments with more or less similar densities (I.e. the Σ5 parameter). From the analysis of the spectral energy distributions of galaxies in our samples based on MAGPHYS, we find that galaxies in the red sample (of any morphological type) have dust masses similar to those in the blue sample (I.e. normal spiral/star-forming systems). However, in comparison to the red-spirals and in particular blue systems, red-ellipticals have lower mean dust-to-stellar mass ratios. Besides galaxies in the red-elliptical sample have much lower mean star formation/specific star formation rates in contrast to their counterparts in the blue sample. Our results support a scenario where dust in early-type systems is likely to be of an external origin.

The effect of accretion environment at large radius on hot accretion flows

NASA Astrophysics Data System (ADS)

Yang, Xiao-Hong; Bu, De-Fu

2018-05-01

We study the effects of accretion environment (gas density, temperature, and angular momentum) at large radii (˜10 pc) on luminosity of hot accretion flows. The radiative feedback effects from the accretion flow on the accretion environment are also self-consistently taken into account. We find that the slowly rotating flows at large radii can significantly deviate from Bondi accretion when radiation heating and cooling are considered. We further find that when the temperature of environment gas is low (e.g. T = 2 × 107 K), the luminosity of hot accretion flows is high. When the temperature of gas is high (e.g. T ≥ 4 × 107 K), the luminosity of hot accretion flow significantly deceases. The environment gas density can also significantly influence the luminosity of accretion flows. When density is higher than ˜4 × 10-22 g cm-3 and temperature is lower than 2 × 107 K, hot accretion flow with luminosity lower than 2 per cent LEdd is not present. Therefore, the parsec-scale environment density and temperature are two important parameters to determine the luminosity. The results are also useful for the subgrid models adopted by the cosmological simulations.

METHOD AND FLUX COMPOSITION FOR TREATING URANIUM

DOEpatents

Foote, F.

1958-08-23

ABS>A flux composition is described fer use with molten uranium or uranium alloys. The flux consists of about 46 weight per cent calcium fiuoride, 46 weight per cent magnesium fluoride and about 8 weight per cent of uranium tetrafiuoride.

Self-actuated shutdown-system development: system response-analysis status

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

Deane, N.A.; Gregoire, K.E.; Tatsumi, J.T.

1980-09-01

This report provides a preliminary evaluation of the SASS response time requirements for the safe shutdown earthquake (SSE), the flow coastdown (FCD), and two transient overpower (TOP) events. The driving functions for the SSE are a 20 cent step reactivity insertion with a +- 60 cent oscillation super imposed for 10 seconds combined with a flow coastdown defined by F/F/sub (0)/ = 1/(1+.2788t). The driving function of the FCD is just the relative flow curve defined above for the SSE. The TOP event driving function represents a control rod runout to a total of 60 cents at ramp rates ofmore » .76 cents/s and 6.1 cents/s. 3 figures.« less

Warming alters the metabolic balance of ecosystems

PubMed Central

Yvon-Durocher, Gabriel; Jones, J. Iwan; Trimmer, Mark; Woodward, Guy; Montoya, Jose M.

2010-01-01

The carbon cycle modulates climate change, via the regulation of atmospheric CO2, and it represents one of the most important services provided by ecosystems. However, considerable uncertainties remain concerning potential feedback between the biota and the climate. In particular, it is unclear how global warming will affect the metabolic balance between the photosynthetic fixation and respiratory release of CO2 at the ecosystem scale. Here, we present a combination of experimental field data from freshwater mesocosms, and theoretical predictions derived from the metabolic theory of ecology to investigate whether warming will alter the capacity of ecosystems to absorb CO2. Our manipulative experiment simulated the temperature increases predicted for the end of the century and revealed that ecosystem respiration increased at a faster rate than primary production, reducing carbon sequestration by 13 per cent. These results confirmed our theoretical predictions based on the differential activation energies of these two processes. Using only the activation energies for whole ecosystem photosynthesis and respiration we provide a theoretical prediction that accurately quantified the precise magnitude of the reduction in carbon sequestration observed experimentally. We suggest the combination of whole-ecosystem manipulative experiments and ecological theory is one of the most promising and fruitful research areas to predict the impacts of climate change on key ecosystem services. PMID:20513719

The thin hot plume beneath Iceland

USGS Publications Warehouse

Allen, R.M.; Nolet, G.; Morgan, W.J.; Vogfjord, K.; Bergsson, B.H.; Erlendsson, P.; Foulger, G.R.; Jakobsdottir, S.; Julian, B.R.; Pritchard, M.; Ragnarsson, S.; Stefansson, R.

1999-01-01

We present the results of a seismological investigation of the frequency-dependent amplitude variations across Iceland using data from the HOTSPOT array currently deployed there. The array is composed of 30 broad-band PASSCAL instruments. We use the parameter t(*), defined in the usual manner from spectral ratios (Halderman and Davis 1991), to compare observed S-wave amplitude variations with those predicted due to both anelastic attenuation and diffraction effects. Four teleseismic events at a range of azimuths are used to measure t(*). A 2-D vertical cylindrical plume model with a Gaussian-shaped velocity anomaly is used to model the variations. That part of t(*) caused by attenuation was estimated by tracing a ray through IASP91, then superimposing our plume model velocity anomaly and calculating the path integral of 1/vQ. That part of t(*) caused by diffraction was estimated using a 2-D finite difference code to generate synthetic seismograms. The same spectral ratio technique used for the data was then used to extract a predicted t(*). The t(*) variations caused by anelastic attenuation are unable to account for the variations we observe, but those caused by diffraction do. We calculate the t(*) variations caused by diffraction for different plume models and obtain our best-fit plume, which exhibits good agreement between the observed and measured t(*). The best-fit plume model has a maximum S-velocity anomaly of - 12 per cent and falls to 1/e of its maximum at 100 km from the plume centre. This is narrower than previous estimates from seismic tomography, which are broadened and damped by the methods of tomography. This velocity model would suggest greater ray theoretical traveltime delays than observed. However, we find that for such a plume, wave-front healing effects at frequencies of 0.03-0.175 Hz (the frequency range used to pick S-wave arrivals) causes a 40 per cent reduction in traveltime delay, reducing the ray theoretical delay to that observed.

Omission of polysomnography in treatment of snoring: common reasons and medico-legal implications.

PubMed

Goh, Y H; Choy, D K

2000-07-01

Although polysomnography (PSG) is an important investigation in the treatment of snorers, it was observed that a large number of patients did not have pre-operative PSG assessment in a tertiary hospital in Singapore. Of the 118 Asian patients who underwent surgery for snoring from January 1997 to December 1998, 36 (30.5 per cent) of patients did not have pre-operative PSG and only 21 (17.8 per cent) of patients had post-operative PSG. In this cohort, 43 (36.4 per cent) patients presented with snoring as their only complaint and not associated with symptoms indicative of obstructive sleep apnoea syndrome (OSAS). Thirty-one of these 'simple snorers' underwent sleep studies with the following outcome: two (6.5 per cent) true simple snorers, two (6.5 per cent) upper airway resistance syndrome, nine (29 per cent) mild OSAS, seven (22.6 per cent) moderate OSAS and 11 (35.5 per cent) severe OSAS. Our study showed that without the aid of PSG, it would be difficult to predict the severity of sleep apnoea based on clinical history alone. In an increasingly litigation-conscious society such as Singapore, there is therefore little justification in omitting PSG in the treatment of snoring. The common reasons for omission of pre-operative PSG and the medico-legal implications are also discussed.

Prevalence of wet litter and the associated risk factors in broiler flocks in the United Kingdom.

PubMed

Hermans, P G; Fradkin, D; Muchnik, I B; Organ, K L

2006-05-06

A postal questionnaire was sent to the managers of 857 broiler farms in the UK to determine the prevalence and risk factors for wet litter. The response rate was 75 per cent. Wet litter was reported by 75 per cent (95 per cent confidence interval [CI] 71.3 to 78.3) of the respondents in at least one flock during the year 2001 and 56.1 per cent (95 per cent CI 52.0 to 60.0) of them reported that they had an outbreak of wet litter in their most recently reared flock. Wet litter occurred more often during the winter months and farms using side ventilation systems were at an increased risk (odds ratio 1.74; 95 per cent CI 1.09 to 2.76). A multivariable analysis was carried out using two different definitions of wet litter as outcome variables - all cases of wet litter, and cases of wet litter associated with disease. Consistent risk factors for both outcomes were coccidiosis, feed equipment failures and the availability of separate farm clothing for each house. Cases of wet litter associated with disease were reported by 33.7 per cent (95 per cent CI 28.8 to 39.1) of the managers in their last flock and were associated with the use of hand sanitisers and broiler houses with walls made of concrete.

Woodcock status report, 1960

USGS Publications Warehouse

Robbins, C.S.

1960-01-01

Singing ground counts for 1960 from 40 routes west of the Appalachians and 166 routes east of this range were available for comparison with counts made on the same routes in 1959. While the measurements of change in the woodcock breeding index between years relate, properly speaking, only to these routes as selected by the cooperators, this is the best information we have on the breeding population of the area east of Wisconsin and north of Tennessee and South Carolina.* East of the Appalachians the sample data indicated a statistically significant decrease of 10 per cent, and it probably is safe to conclude that the true drop did not exceed 19 per cent. West of the Appalachians an average increase of 7 per cent was indicated, and 95 per cent confidence limits suggest- that if a decrease did occur on the sample routes, it probably was not more than 13 per cent. For both areas combined, a decrease of 2 per cent was recorded on the 206 routes sampled, with confidence limits of an increase of 9 per cent or a decrease of 12 per cent. There is no evidence of a disastrous population decrease in spite of the severe weather conditions of March 1960. *No comparative data were available from Indiana, Quebec, Rhode Island, Delaware or Virginia; and only one route in Minnesota and one in Wisconsin were covered both years.

Electronic properties of Laves phase ZrFe{sub 2} using Compton spectroscopy

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

Bhatt, Samir, E-mail: sameerbhatto11@gmail.com; Kumar, Kishor; Ahuja, B. L.

First-ever experimental Compton profile of Laves phase ZrFe{sub 2}, using indigenous 20 Ci {sup 137}Cs Compton spectrometer, is presented. To analyze the experimental electron momentum density, we have deduced the theoretical Compton profiles using density functional theory (DFT) and hybridization of DFT and Hartree-Fock scheme within linear combination of atomic orbitals (LCAO) method. The energy bands and density of states are also calculated using LCAO prescription. The theoretical profile based on local density approximation gives a better agreement with the experimental profile than other reported schemes. The present investigations validate the inclusion of correlation potential of Perdew-Zunger in predicting themore » electronic properties of ZrFe{sub 2}.« less

Time-dependent density functional theory (TD-DFT) coupled with reference interaction site model self-consistent field explicitly including spatial electron density distribution (RISM-SCF-SEDD)

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

Yokogawa, D., E-mail: d.yokogawa@chem.nagoya-u.ac.jp; Institute of Transformative Bio-Molecules

2016-09-07

Theoretical approach to design bright bio-imaging molecules is one of the most progressing ones. However, because of the system size and computational accuracy, the number of theoretical studies is limited to our knowledge. To overcome the difficulties, we developed a new method based on reference interaction site model self-consistent field explicitly including spatial electron density distribution and time-dependent density functional theory. We applied it to the calculation of indole and 5-cyanoindole at ground and excited states in gas and solution phases. The changes in the optimized geometries were clearly explained with resonance structures and the Stokes shift was correctly reproduced.

Role of clay minerals in the transportation of iron

USGS Publications Warehouse

Carroll, D.

1958-01-01

The clay minerals have iron associated with them in several ways: 1. (1) as an essential constituent 2. (2) as a minor constituent within the crystal lattice where it is in isomorphous substitution and 3. (3) as iron oxide on the surface of the mineral platelets. Nontronite, "hydromica," some chlorites, vermiculite, glauconite and chamosite contain iron as an essential constituent. Kaolinite and halloysite have no site within the lattice for iron, but in certain environments iron oxide (goethite or hematite) is intimately associated as a coating on the micelles. Analyses of clay minerals show that the content of Fe2O3 varies: 29 per cent (nontronite), 7??3 per cent (griffithite), 4.5 per cent ("hydromica"), 5.5 per cent (chlorite), 4 per cent (vermiculite) and 18 per cent (glauconite). The FeO content is: 40 per cent (chamosite), 7.8 per cent (griffithite), 1-2 per cent ("hydromica"), 3 per cent (glauconite) and 2 per cent (chlorite). The iron associated with the clay minerals remains stable in the environment in which the minerals occur, but if either pH or Eh or both are changed the iron may be affected. Change of environment will cause: 1. (1) removal of iron by reduction of Fe3+ to Fe2+; 2. (2) ion-exchange reactions; 3. (3) instability of the crystal lattice. Experiments using bacterial activity to produce reducing conditions with kaolinite and halloysite coated with iron oxides and with nontronite in which ferric iron is in the octahedral position within the lattice showed that ferric oxide is removed at Eh +0??215 in fresh water and at Eh +0.098 in sea water. Hematite, goethite, and indefinite iron oxides were removed at different rates. Red ferric oxides were changed to black indefinite noncrystalline ferrous sulphide at Eh -0.020 but reverted to ferric oxide under oxidizing conditions. Nontronite turned bright green under reducing conditions and some of the ferrous iron remained within the lattice on a return to oxidizing conditions. Bacterial activity seems to be necessary for maintaining reducing conditions in the environments studied. ?? 1958.

Problems associated with restorative materials--dentists' views in Finland and Sweden.

PubMed

Widström, E; Sundberg, H

1991-01-01

During the past 10-15 years the possible side-effects of dental restorative materials, especially due to amalgam fillings, have caused a lively debate in Sweden. There is an extensive literature on the chemical and biological properties of dental materials but no investigations have dealt with the providers' attitudes. The purpose of this study was to find out the dentists' experiences of and attitudes to patients who state they have problems related to dental restorative materials and compare the dentists' subjective assessments of those side-effects in two neighboring countries, Finland and Sweden. Information was collected by postal questionnaires addressed to dentists chosen at random in Finland (n = 625) and in Sweden (n = 960). The response rate was 73 per cent and 72 per cent respectively. The results showed that 99 per cent of the respondents had patients questioning the safety of dental materials. The number of such patients was estimated to be three times higher in Sweden (124 patients per dentist in 1989) than in Finland (39 patients per dentist). More than 90 per cent of the questions from the patients regarded amalgam fillings. Statistically significant differences were found between the respondents' opinions of amalgam, 81 per cent of the Finnish contrary to 59 per cent of the Swedish respondents considered the risk of side-effects to be low when using this material. About 90 per cent of the respondents considered glass-ionomer, gold and ceramic restorations safe, but only half of them were convinced of the safety of composite. A great majority of the Swedish respondents (79 per cent) claimed that the patients should get their fillings changed without odontologic indications if they insisted on it and paid for the treatment in comparison to 22 per cent of the Finnish respondents (p less than 0.001). In case dental insurance was to pay for this kind of treatment it was accepted by 6 per cent of the Finns and 25 per cent of the Swedes. The attitude to amalgam was in general less favorable among the dentists in Sweden than in Finland.

Scale Control and Quality Management of Printed Image Parameters

NASA Astrophysics Data System (ADS)

Novoselskaya, O. A.; Kolesnikov, V. L.; Solov'eva, T. V.; Nagornova, I. V.; Babluyk, E. B.; Trapeznikova, O. V.

2017-06-01

The article provides a comparison of the main valuation techniques for a regulated parameter of printability of the offset paper by current standards GOST 24356 and ISO 3783: 2006. The results of development and implementation of a complex test scale for management and control the quality of printed production are represented. The estimation scale is introduced. It includes normalized parameters of print optical density, print uniformity, picking out speed, the value of dot gain, print contrast with the added criteria of minimizing microtexts, a paper slip, resolution threshold and effusing ability of paper surface. The results of analysis allow directionally form surface properties of the substrate to facilitate achieving the required quality of the printed image parameters, i. e. optical density of a print at a predetermined level not less than 1.3, the print uniformity with minimal deviation of dot gain about the order of 10 per cents.

Fast Reacting Nano Composite Energetic Materials: Synthesis and Combustion Characterization

DTIC Science & Technology

2015-08-24

mg of composite resulting in a loose powder fill estimated to be 7% of the theoretical maximum density. Once prepared, the tube was placed in a steel ...theoretical maximum density. Once prepared, the tube was placed in a steel combustion chamber and the experimental setup is schematically represented... Valery Levitas. "Effect of oxide shell growth on ano- aluminum thermite propagation rates." Combustion and Flame 159 (2012): 3448-3453. I. Liakosa

Collision dynamics of H+ + N2 at low energies based on time-dependent density-functional theory

NASA Astrophysics Data System (ADS)

Yu, W.; Zhang, Y.; Zhang, F. S.; Hutton, R.; Zou, Y.; Gao, C.-Z.; Wei, B.

2018-02-01

Using time-dependent density-functional theory at the level of local density approximation augmented by a self-interaction correction and coupled non-adiabatically to molecular dynamics, we study, from a theoretical perspective, scattering dynamics of the proton in collisions with the N2 molecule at 30 eV. Nine different collision configurations are employed to analyze the proton energy loss spectra, electron depletion, scattering angles and self-interaction effects. Our results agree qualitatively with the experimental data and previous theoretical calculations. The discrepancies are ascribed to the limitation of the theoretical models in use. We find that self-interaction effects can significantly influence the electron capture and the excited diatomic vibrational motion, which is in consistent with other calculations. In addition, it is found that the molecular structure can be readily retrieved from the proton energy loss spectra due to a significant momentum transfer in head-on collisions.

Axisymmetric Eigenmodes of Spheroidal Pure Electron Plasmas

NASA Astrophysics Data System (ADS)

Kawai, Yosuke; Saitoh, Haruhiko; Yoshida, Zensho; Kiwamoto, Yasuhito

2010-11-01

The axisymmetric electrostatic eigenmodes of spheroidal pure electron plasmas have been studied experimentally. It is confirmed that the observed spheroidal plasma attains a theoretically expected equilibrium density distribution, with the exception of a low-density halo distribution surrounding the plasma. When the eigenmode frequency observed for the plasma is compared with the frequency predicted by the dispersion relation derived under ideal conditions wherein the temperature is zero and the boundary is located at an infinite distance from the plasma, it is observed that the absolute value of the observed frequency is systematically higher than the theoretical prediction. Experimental examinations and numerical calculations indicate that the upward shift of the eigenmode frequency cannot be accounted for solely by the finite temperature effect, but is significantly affected by image charges induced on the conducting boundary and the resulting distortion of the density profile from the theoretical expectation.

Risk factor profile for non-communicable diseases among Mishing tribes in Assam, India: results from a WHO STEPs survey.

PubMed

Misra, Palash Jyoti; Mini, G K; Thankappan, K R

2014-09-01

A comprehensive risk factor profile of non-communicable diseases (NCDs) as suggested by the World Health Organization (WHO) has not been reported from tribal population in India. This survey was carried out to assess the prevalence of NCD risk factors among Mishing tribes in Assam using the WHO STEPs approach. A total of 332 individuals of the Mishing tribe (men 54%) aged 25-64 yr were selected from Tinsukia district by multistage cluster sampling. Using the WHO STEPs approach information was collected on demographics, STEP 1 variables (tobacco, alcohol, physical activity, diet) and measured STEP 2 variables (weight, height, waist circumference and blood pressure). Multivariate analysis was used to find the relation between STEP 1 and STEP 2 variables. Overall, tobacco use was 84 per cent (men 94%; women 73%, p0 <0.001) and alcohol use was 67 per cent (men 82%; women 50%, p0 <0.05); 86 per cent reported vigorous physical activity, (men 91%, women 82%; p0 < 0.05). Sixty eight per cent reported to consume unhealthy diet (less than five servings of fruits and vegetables/day), 11 per cent had abdominal obesity, 16 per cent were overweight and 26 per cent had hypertension. Non users of tobacco and those who consumed more fruits and vegetables had higher prevalence of overweight ( p0 <0.05). Among the hypertensives, 24 per cent were aware, 17 per cent treated and 2.4 per cent controlled their hypertension. Older individuals had higher hypertension prevalence ( p0 <0.05) compared to younger individuals. Tobacco use, alcohol use and unhealthy diet habits were high among men and women in this population and were major NCD risk factors. An integrated approach of culturally appropriate population level and high risk strategies are warranted to reduce these risk factors and to enhance adequate control of hypertension.

Risk factor profile for non-communicable diseases among Mishing tribes in Assam, India: Results from a WHO STEPs survey

PubMed Central

Misra, Palash Jyoti; Mini, G.K.; Thankappan, K.R.

2014-01-01

Background & objectives: A comprehensive risk factor profile of non-communicable diseases (NCDs) as suggested by the World Health Organization (WHO) has not been reported from tribal population in India. This survey was carried out to assess the prevalence of NCD risk factors among Mishing tribes in Assam using the WHO STEPs approach. Methods: A total of 332 individuals of the Mishing tribe (men 54%) aged 25-64 yr were selected from Tinsukia district by multistage cluster sampling. Using the WHO STEPs approach information was collected on demographics, STEP 1 variables (tobacco, alcohol, physical activity, diet) and measured STEP 2 variables (weight, height, waist circumference and blood pressure). Multivariate analysis was used to find the relation between STEP 1 and STEP 2 variables. Results: Overall, tobacco use was 84 per cent (men 94%; women 73%, P<0.001) and alcohol use was 67 per cent (men 82%; women 50%, P<0.05); 86 per cent reported vigorous physical activity, (men 91%, women 82%; P < 0.05). Sixty eight per cent reported to consume unhealthy diet (less than five servings of fruits and vegetables/day), 11 per cent had abdominal obesity, 16 per cent were overweight and 26 per cent had hypertension. Non users of tobacco and those who consumed more fruits and vegetables had higher prevalence of overweight (P<0.05). Among the hypertensives, 24 per cent were aware, 17 per cent treated and 2.4 per cent controlled their hypertension. Older individuals had higher hypertension prevalence (P<0.05) compared to younger individuals. Interpretation & conclusions: Tobacco use, alcohol use and unhealthy diet habits were high among men and women in this population and were major NCD risk factors. An integrated approach of culturally appropriate population level and high risk strategies are warranted to reduce these risk factors and to enhance adequate control of hypertension. PMID:25366204

Meta‐analysis of antibiotics versus appendicectomy for non‐perforated acute appendicitis

PubMed Central

Sallinen, V.; Akl, E. A.; You, J. J.; Agarwal, A.; Shoucair, S.; Vandvik, P. O.; Agoritsas, T.; Heels‐Ansdell, D.; Guyatt, G. H.

2016-01-01

Abstract Background For more than a century, appendicectomy has been the treatment of choice for appendicitis. Recent trials have challenged this view. This study assessed the benefits and harms of antibiotic therapy compared with appendicectomy in patients with non‐perforated appendicitis. Methods A comprehensive search was conducted for randomized trials comparing antibiotic therapy with appendicectomy in patients with non‐perforated appendicitis. Key outcomes were analysed using random‐effects meta‐analysis, and the quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Results Five studies including 1116 patients reported major complications in 25 (4·9 per cent) of 510 patients in the antibiotic and 41 (8·4 per cent) of 489 in the appendicectomy group: risk difference −2·6 (95 per cent c.i. –6·3 to 1·1) per cent (low‐quality evidence). Minor complications occurred in 11 (2·2 per cent) of 510 and 61 (12·5 per cent) of 489 patients respectively: risk difference −7·2 (−18·1 to 3·8) per cent (very low‐quality evidence). Of 550 patients in the antibiotic group, 47 underwent appendicectomy within 1 month: pooled estimate 8·2 (95 per cent c.i. 5·2 to 11·8) per cent (high‐quality evidence). Within 1 year, appendicitis recurred in 114 of 510 patients in the antibiotic group: pooled estimate 22·6 (15·6 to 30·4) per cent (high‐quality evidence). For every 100 patients with non‐perforated appendicitis, initial antibiotic therapy compared with prompt appendicectomy may result in 92 fewer patients receiving surgery within the first month, and 23 more experiencing recurrent appendicitis within the first year. Conclusion The choice of medical versus surgical management in patients with clearly uncomplicated appendicitis is value‐ and preference‐dependent, suggesting a change in practice towards shared decision‐making is necessary. PMID:26990957

The prevalence of refractive errors among adult rural populations in Iran.

PubMed

Hashemi, Hassan; Nabovati, Payam; Yekta, Abbasali; Shokrollahzadeh, Fereshteh; Khabazkhoob, Mehdi

2018-01-01

The aim was to determine the prevalence of myopia and hyperopia and related factors in underserved rural areas in Iran. Under random cluster sampling, two rural regions were randomly selected in the north and southwest of the country, and 3,061 persons over 15 years of age were invited into the study. After selecting samples, all participants had refraction, measurement of uncorrected vision and visual acuity and ocular health examination by slitlamp biomicroscopy. Of the 3,061 invitees, 2,575 participated in the study (response rate: 84.1 per cent). After excluding those who met the exclusion criteria or had missing refractive data, eventually there were 2,518 subjects available for this analysis. The mean age of the participants was 44.3 ± 17.5 years (range: 16 to 93 years) and 1,460 of them (58.0 per cent) were female. The overall prevalence of myopia and hyperopia in this study was 25.2 per cent (95 per cent CI: 23.2 to 27.2) and 22.5 per cent (95 per cent CI: 20.6 to 24.4), respectively. The prevalence of myopia increased from 20.9 per cent in participants 16 to 20 years to 32.9 per cent in the 21 to 30 years age group, declined up to the age of 60 years and increased again afterwards. The lowest prevalence was 6.8 per cent observed in the 16 to 20 years age group and the highest was 45.8 per cent in 61- to 70-year-olds. In the final logistic regression model, myopia significantly associated with age, higher education levels and cataracts, while hyperopia associated with age, lower education levels and male gender. In our study, the prevalence of myopia was lower and the prevalence of hyperopia was higher compared to most previous studies. The findings of this study imply that refractive errors vary by age. © 2017 Optometry Australia.

Meta-analysis of antibiotics versus appendicectomy for non-perforated acute appendicitis.

PubMed

Sallinen, V; Akl, E A; You, J J; Agarwal, A; Shoucair, S; Vandvik, P O; Agoritsas, T; Heels-Ansdell, D; Guyatt, G H; Tikkinen, K A O

2016-05-01

For more than a century, appendicectomy has been the treatment of choice for appendicitis. Recent trials have challenged this view. This study assessed the benefits and harms of antibiotic therapy compared with appendicectomy in patients with non-perforated appendicitis. A comprehensive search was conducted for randomized trials comparing antibiotic therapy with appendicectomy in patients with non-perforated appendicitis. Key outcomes were analysed using random-effects meta-analysis, and the quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Five studies including 1116 patients reported major complications in 25 (4·9 per cent) of 510 patients in the antibiotic and 41 (8·4 per cent) of 489 in the appendicectomy group: risk difference -2·6 (95 per cent c.i. -6·3 to 1·1) per cent (low-quality evidence). Minor complications occurred in 11 (2·2 per cent) of 510 and 61 (12·5 per cent) of 489 patients respectively: risk difference -7·2 (-18·1 to 3·8) per cent (very low-quality evidence). Of 550 patients in the antibiotic group, 47 underwent appendicectomy within 1 month: pooled estimate 8·2 (95 per cent c.i. 5·2 to 11·8) per cent (high-quality evidence). Within 1 year, appendicitis recurred in 114 of 510 patients in the antibiotic group: pooled estimate 22·6 (15·6 to 30·4) per cent (high-quality evidence). For every 100 patients with non-perforated appendicitis, initial antibiotic therapy compared with prompt appendicectomy may result in 92 fewer patients receiving surgery within the first month, and 23 more experiencing recurrent appendicitis within the first year. The choice of medical versus surgical management in patients with clearly uncomplicated appendicitis is value- and preference-dependent, suggesting a change in practice towards shared decision-making is necessary. © 2016 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

Feline hyperthyroidism reported in primary-care veterinary practices in England: prevalence, associated factors and spatial distribution.

PubMed

Stephens, M J; O'Neill, D G; Church, D B; McGreevy, P D; Thomson, P C; Brodbelt, D C

2014-11-08

Feline hyperthyroidism is a commonly diagnosed endocrinopathy that can have a substantial deleterious impact on the welfare of affected cats. This study aimed to estimate the prevalence, associated factors and geographical distribution for feline hyperthyroidism in England, using primary-care veterinary practice clinical data from the VetCompass Animal Surveillance Project. Prevalence was estimated from the overall cat cohort. Associated factor analysis used an age-matched, nested, case-control design with multivariable logistic regression. There were 2,276 cases of feline hyperthyroidism identified from 95,629 cats attending 84 practices from September 2009 to December 2011. Cases were aged 6-25 years. 3.7 per cent of cases and 9.9 per cent of controls were purebred, 56.4 per cent of cases and 56.5 per cent of controls were female, and 88.1 per cent of cases and 86.0 per cent of controls were neutered. The apparent prevalence was 2.4 per cent (95% CI 2.3 to 2.5 per cent) overall, and 8.7 per cent (95% CI 8.3 to 9.0 per cent) in cats aged 10 years or above. Burmese (OR 0.15, 95% CI 0.07 to 0.32, P<0.0001), Persian (OR 0.17, 95% CI 0.08 to 0.33, P<0.0001), Siamese (OR 0.4, 95% CI 0.21 to 0.75, P=0.004) and purebred cats overall (OR 0.33, 95% CI 0.25 to 0.42, P< 0.0001) had lower odds of feline hyperthyroidism than non-purebred cats. Insured cats had increased odds (OR 1.78, 95% CI 1.56 to 2.03, P< 0.001). There was little evidence of spatial variation. This study highlights feline hyperthyroidism as a high-prevalence disease in England, and reports reduced odds of diagnosis in certain breeds and purebred cats overall. British Veterinary Association.

Coagulation Profile Changes Due to Thromboprophylaxis and Platelets in Trauma Patients at High-Risk for Venous Thromboembolism.

PubMed

Allen, Casey J; Murray, Clark R; Meizoso, Jonathan P; Ray, Juliet J; Teisch, Laura F; Ruiz, Xiomara D; Hanna, Mena M; Guarch, Gerardo A; Manning, Ronald J; Livingstone, Alan S; Ginzburg, Enrique; Schulman, Carl I; Namias, Nicholas; Proctor, Kenneth G

2015-07-01

We hypothesize there are coagulation profile changes associated both with initiation of thromboporphylaxis (TPX) and with change in platelet levels in trauma patients at high-risk for venous thromboembolism (VTE). A total of 1203 trauma intensive care unit patients were screened with a VTE risk assessment profile. In all, 302 high-risk patients (risk assessment profile score ≥ 10) were consented for weekly thromboelastography. TPX was initiated between initial and follow-up thromboelastography. Seventy-four patients were analyzed. Upon admission, 87 per cent were hypercoagulable, and 81 per cent remained hypercoagulable by Day 7 (P = 0.504). TPX was initiated 3.4 ± 1.4 days after admission; 68 per cent received unfractionated heparin and 32 per cent received low-molecular-weight heparin. The VTE rate was 18 per cent, length of stay 38 (25-37) days, and mortality of 17.6 per cent. In all, 76 per cent had a rapid clotting time at admission versus 39 per cent at Day 7 (P < 0.001); correcting from 7.75 (6.45-8.90) minutes to 10.45 (7.90-15.25) minutes (P < 0.001). At admission, 41 per cent had an elevated maximum clot formation (MCF) and 85 per cent had at Day 7 (P < 0.001); increasing from 61(55-65) mm to 75(69-80) mm (P < 0.001). Platelets positively correlated with MCF at admission (r = 0.308, R(2) = 0.095, P = 0.008) and at Day 7 (r = 0.516, R(2) = 0.266, P < 0.001). Change in platelet levels correlated with change in MCF (r = 0.332, R(2) = 0.110, P = 0.005). In conclusion, hypercoagulability persists despite the use of TPX. Although clotting time normalizes, MCF increases in correlation with platelet levels. As platelet function is a dominant contributor to sustained trauma-evoked hypercoagulability, antiplatelet therapy may be indicated in the management of severely injured trauma patients.

The perceived and actual diagnostic utility of veterinary cytological samples.

PubMed

Skeldon, N; Dewhurst, E

2009-04-01

To establish the proportion of cytology samples sent to a commercial veterinary laboratory that yields diagnostically useful information in the context of current use and perceptions of cytology. Nine hundred and forty-five cytology submissions were retrospectively collected and categorised according to diagnostic utility. A survey into the use and perceptions of cytology was distributed at the British Small Animal Veterinary Association Congress 2008. A specific diagnosis was reached in 23.1 per cent of samples and a cytological diagnosis in 35.3 per cent. 22.4 per cent of samples yielded some useful information, but 19.2 per cent were unacceptable. Seventy-four participants in the survey took an average of 3.9 cytological samples per week, of which they examined 27.0 per cent in-house only, 21.6 per cent in-house before sending to an external laboratory and 51.4 per cent were sent externally without prior examination. "To obtain a definitive diagnosis" was the principal reason cited for performing cytology. Results suggest that cytology is underused and may be applied in an inappropriate context in the UK. It is hoped that illustrating the diagnostic outcome of samples received by a commercial laboratory will encourage increased, appropriate use of cytology.

Variables influencing condom use in a cohort of gay and bisexual men.

PubMed

Valdiserri, R O; Lyter, D; Leviton, L C; Callahan, C M; Kingsley, L A; Rinaldo, C R

1988-07-01

Nine hundred fifty-five of 1,384 (69 per cent) gay and bisexual men enrolled in a prospective study of the natural history of human immunodeficiency virus (HIV) infection who reported engaging in anal intercourse in the past six months were surveyed about condom use practices for both insertive (IAI) and receptive anal intercourse (RAI). The following results were obtained: 23 per cent of the men reported that they always used condoms for IAI and 21 per cent for RAI; 32 per cent sometimes used condoms for IAI; 28 per cent sometimes used condoms for RAI; 45 per cent never used condoms for IAI; and 50 per cent never used condoms for RAI. Multiple logistic regression analysis revealed that the following variables were associated with both insertive and receptive condom use: condom acceptability; a history of multiple and/or anonymous partners in the past six months, and the number of partners with whom one is "high" (drugs/alcohol) during sex. Knowledge of positive HIV serostatus was more strongly associated with receptive than with insertive use. Condom use is a relatively complex health-related behavior, and condom promotion programs should not limit themselves to stressing the dangers of unprotected intercourse.

[Metastatic breast cancers: comparison of the prognostic significance and the sensitivity to chemotherapy according to the presence of estradiol and progesterone receptors].

PubMed

Pouillart, P; Madgelenat, H; Jouve, M; Palangie, T; Garcia-Giralt, E; Bretaudeau, B; Polijcak, M; Asselain, B

1982-01-01

102 patients with disseminated breast cancer entered this retrospective study. An estrogen receptor (ER) assay was realized in 91 patients and a progesterone receptor (PgR) assay in 90 cases; 44 per cent of the patients were considered as ER+ and 29 per cent as PgR+; 56 per cent were considered as ER- PgR-. The objective response rate to cytotoxic chemotherapy after 4 months of treatment was 66 per cent for ER-, 73 per cent for ER+, 67 per cent for PgR- and 74 per cent for PgR+. However, the mean duration of response was significantly shorter for ER- patients, and no difference appeared between PgR+ and PgR- patients. The acturial survival curves demonstrated a favorable prognostic significance of ER+ as compared to ER- p = 0,03), but the difference was slightly more significant for PgR+ as compared to PgR- (p = 0,008). The prognostic significance of PgR in patients with advanced breast cancer treated with cytotoxic chemotherapy does not appear to be related to the sensitivity to this treatment.

Excited State Charge Transfer reaction with dual emission from 5-(4-dimethylamino-phenyl)-penta-2,4-dienenitrile: Spectral measurement and theoretical density functional theory calculation

NASA Astrophysics Data System (ADS)

Jana, Sankar; Dalapati, Sasanka; Ghosh, Shalini; Kar, Samiran; Guchhait, Nikhil

2011-07-01

The excited state intramolecular charge transfer process in donor-chromophore-acceptor system 5-(4-dimethylamino-phenyl)-penta-2,4-dienenitrile (DMAPPDN) has been investigated by steady state absorption and emission spectroscopy in combination with Density Functional Theory (DFT) calculations. This flexible donor acceptor molecule DMAPPDN shows dual fluorescence corresponding to emission from locally excited and charge transfer state in polar solvent. Large solvatochromic emission shift, effect of variation of pH and HOMO-LUMO molecular orbital pictures support excited state intramolecular charge transfer process. The experimental findings have been correlated with the calculated structure and potential energy surfaces based on the Twisted Intramolecular Charge Transfer (TICT) model obtained at DFT level using B3LYP functional and 6-31+G( d, p) basis set. The theoretical potential energy surfaces for the excited states have been generated in vacuo and acetonitrile solvent using Time Dependent Density Functional Theory (TDDFT) and Time Dependent Density Functional Theory Polarized Continuum Model (TDDFT-PCM) method, respectively. All the theoretical results show well agreement with the experimental observations.

Bulk dynamics of Brownian hard disks: Dynamical density functional theory versus experiments on two-dimensional colloidal hard spheres

NASA Astrophysics Data System (ADS)

Stopper, Daniel; Thorneywork, Alice L.; Dullens, Roel P. A.; Roth, Roland

2018-03-01

Using dynamical density functional theory (DDFT), we theoretically study Brownian self-diffusion and structural relaxation of hard disks and compare to experimental results on quasi two-dimensional colloidal hard spheres. To this end, we calculate the self-van Hove correlation function and distinct van Hove correlation function by extending a recently proposed DDFT-approach for three-dimensional systems to two dimensions. We find that the theoretical results for both self-part and distinct part of the van Hove function are in very good quantitative agreement with the experiments up to relatively high fluid packing fractions of roughly 0.60. However, at even higher densities, deviations between the experiment and the theoretical approach become clearly visible. Upon increasing packing fraction, in experiments, the short-time self-diffusive behavior is strongly affected by hydrodynamic effects and leads to a significant decrease in the respective mean-squared displacement. By contrast, and in accordance with previous simulation studies, the present DDFT, which neglects hydrodynamic effects, shows no dependence on the particle density for this quantity.

The effect of unresolved contaminant stars on the cross-matching of photometric catalogues

NASA Astrophysics Data System (ADS)

Wilson, Tom J.; Naylor, Tim

2017-07-01

A fundamental process in astrophysics is the matching of two photometric catalogues. It is crucial that the correct objects be paired, and that their photometry does not suffer from any spurious additional flux. We compare the positions of sources in Wide-field Infrared Survey Explorer (WISE), INT Photometric H α Survey, Two Micron All Sky Survey and AAVSO Photometric All Sky Survey with Gaia Data Release 1 astrometric positions. We find that the separations are described by a combination of a Gaussian distribution, wider than naively assumed based on their quoted uncertainties, and a large wing, which some authors ascribe to proper motions. We show that this is caused by flux contamination from blended stars not treated separately. We provide linear fits between the quoted Gaussian uncertainty and the core fit to the separation distributions. We show that at least one in three of the stars in the faint half of a given catalogue will suffer from flux contamination above the 1 per cent level when the density of catalogue objects per point spread function area is above approximately 0.005. This has important implications for the creation of composite catalogues. It is important for any closest neighbour matches as there will be a given fraction of matches that are flux contaminated, while some matches will be missed due to significant astrometric perturbation by faint contaminants. In the case of probability-based matching, this contamination affects the probability density function of matches as a function of distance. This effect results in up to 50 per cent fewer counterparts being returned as matches, assuming Gaussian astrometric uncertainties for WISE-Gaia matching in crowded Galactic plane regions, compared with a closest neighbour match.

Galaxy-galaxy weak gravitational lensing in f(R) gravity

NASA Astrophysics Data System (ADS)

Li, Baojiu; Shirasaki, Masato

2018-03-01

We present an analysis of galaxy-galaxy weak gravitational lensing (GGL) in chameleon f(R) gravity - a leading candidate of non-standard gravity models. For the analysis, we have created mock galaxy catalogues based on dark matter haloes from two sets of numerical simulations, using a halo occupation distribution (HOD) prescription which allows a redshift dependence of galaxy number density. To make a fairer comparison between the f(R) and Λ cold dark matter (ΛCDM) models, their HOD parameters are tuned so that the galaxy two-point correlation functions in real space (and therefore the projected two-point correlation functions) match. While the f(R) model predicts an enhancement of the convergence power spectrum by up to ˜ 30 per cent compared to the standard ΛCDM model with the same parameters, the maximum enhancement of GGL is only half as large and less than 5 per cent on separations above ˜1-2 h-1 Mpc, because the latter is a cross-correlation of shear (or matter, which is more strongly affected by modified gravity) and galaxy (which is weakly affected given the good match between galaxy autocorrelations in the two models) fields. We also study the possibility of reconstructing the matter power spectrum by combination of GGL and galaxy clustering in f(R) gravity. We find that the galaxy-matter cross-correlation coefficient remains at unity down to ˜2-3 h-1 Mpc at relevant redshifts even in f(R) gravity, indicating joint analysis of GGL and galaxy clustering can be a powerful probe of matter density fluctuations in chameleon gravity. The scale dependence of the model differences in their predictions of GGL can potentially allows us to break the degeneracy between f(R) gravity and other cosmological parameters such as Ωm and σ8.

The JCMT Gould Belt Survey: the effect of molecular contamination in SCUBA-2 observations of Orion A

NASA Astrophysics Data System (ADS)

Coudé, S.; Bastien, P.; Kirk, H.; Johnstone, D.; Drabek-Maunder, E.; Graves, S.; Hatchell, J.; Chapin, E. L.; Gibb, A. G.; Matthews, B.; JCMT Gould Belt Survey Team

2016-04-01

Thermal emission from cold dust grains in giant molecular clouds can be used to probe the physical properties, such as density, temperature and emissivity in star-forming regions. We present the Submillimetre Common-User Bolometer Array (SCUBA-2) shared-risk observations at 450 and 850 μm of the Orion A molecular cloud complex taken at the James Clerk Maxwell Telescope (JCMT). Previous studies showed that molecular emission lines can contribute significantly to the measured fluxes in those continuum bands. We use the Heterodyne Array Receiver Programme 12CO J = 3-2 integrated intensity map for Orion A in order to evaluate the molecular line contamination and its effects on the SCUBA-2 maps. With the corrected fluxes, we have obtained a new spectral index α map for the thermal emission of dust in the well-known integral-shaped filament. Furthermore, we compare a sample of 33 sources, selected over the Orion A molecular cloud complex for their high 12CO J = 3-2 line contamination, to 27 previously identified clumps in OMC 4. This allows us to quantify the effect of line contamination on the ratio of 850-450 μm flux densities and how it modifies the deduced spectral index of emissivity β for the dust grains. We also show that at least one Spitzer-identified protostellar core in OMC 5 has a 12CO J = 3-2 contamination level of 16 per cent. Furthermore, we find the strongest contamination level (44 per cent) towards a young star with disc near OMC 2. This work is part of the JCMT Gould Belt Legacy Survey.

Assessing the accuracy of a point-of-care analyzer for hyperlipidaemia in western Kenya.

PubMed

Park, Paul H; Chege, Patrick; Hagedorn, Isabel C; Kwena, Arthur; Bloomfield, Gerald S; Pastakia, Sonak D

2016-03-01

The prevalence of hyperlipidaemia, along with other non-communicable diseases, is on the rise in low- and middle-income countries. CardioChek PA is a point-of-care lipid measuring device, which seeks to overcome laboratory-based diagnostic barriers by providing immediate results without dependency on significant laboratory infrastructure. However, it has not been validated in Kenya. In this study, we assess the accuracy of CardioChek PA with respect to the gold standard laboratory-based testing. In Webuye, Kenya, two blood samples were collected from 246 subjects to simultaneously measure the lipid levels via both CardioChek PA and the gold standard. All subjects were adults, and geographic stratified sampling methods were applied. Statistical analysis of the device's accuracy was based on per cent bias parameters, as established by the United States National Institutes of Health (NIH). The NIH recommends that per cent bias be ≤±3% for low-density lipoprotein (LDL) cholesterol, ≤±5% for high-density lipoprotein (HDL) cholesterol, ≤±5% for total cholesterol (TC) and ≤±4% for triglycerides (TG). Risk group misclassification rates were also analysed. The CardioChek PA analyzer was substantially inaccurate for LDL cholesterol (-25.9% bias), HDL cholesterol (-8.2% bias) and TC (-15.9% bias). Moreover, those patients at higher risk of complications from hyperlipidaemia were most likely to be misclassified into a lower risk category. CardioChek PA is inaccurate and not suitable for our clinical setting. Furthermore, our findings highlight the need to validate new diagnostic tools in the appropriate setting prior to scale up regardless of their potential for novel utility. © 2015 John Wiley & Sons Ltd.

The Herschel Bright Sources (HerBS): sample definition and SCUBA-2 observations

NASA Astrophysics Data System (ADS)

Bakx, Tom J. L. C.; Eales, S. A.; Negrello, M.; Smith, M. W. L.; Valiante, E.; Holland, W. S.; Baes, M.; Bourne, N.; Clements, D. L.; Dannerbauer, H.; De Zotti, G.; Dunne, L.; Dye, S.; Furlanetto, C.; Ivison, R. J.; Maddox, S.; Marchetti, L.; Michałowski, M. J.; Omont, A.; Oteo, I.; Wardlow, J. L.; van der Werf, P.; Yang, C.

2018-01-01

We present the Herschel Bright Sources (HerBS) sample, a sample of bright, high-redshift Herschel sources detected in the 616.4 deg2 Herschel Astrophysical Terahertz Large Area Survey. The HerBS sample contains 209 galaxies, selected with a 500 μm flux density greater than 80 mJy and an estimated redshift greater than 2. The sample consists of a combination of hyperluminous infrared galaxies and lensed ultraluminous infrared galaxies during the epoch of peak cosmic star formation. In this paper, we present Submillimetre Common-User Bolometer Array 2 (SCUBA-2) observations at 850 μm of 189 galaxies of the HerBS sample, 152 of these sources were detected. We fit a spectral template to the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) and 850 μm SCUBA-2 flux densities of 22 sources with spectroscopically determined redshifts, using a two-component modified blackbody spectrum as a template. We find a cold- and hot-dust temperature of 21.29_{-1.66}^{+1.35} and 45.80_{-3.48}^{+2.88} K, a cold-to-hot dust mass ratio of 26.62_{-6.74}^{+5.61} and a β of 1.83_{-0.28}^{+0.14}. The poor quality of the fit suggests that the sample of galaxies is too diverse to be explained by our simple model. Comparison of our sample to a galaxy evolution model indicates that the fraction of lenses are high. Out of the 152 SCUBA-2 detected galaxies, the model predicts 128.4 ± 2.1 of those galaxies to be lensed (84.5 per cent). The SPIRE 500 μm flux suggests that out of all 209 HerBS sources, we expect 158.1 ± 1.7 lensed sources, giving a total lensing fraction of 76 per cent.

Compton thick absorber in type 1 quasar 3C 345 revealed by Suzaku and Swift/BAT

NASA Astrophysics Data System (ADS)

Eguchi, Satoshi

2017-07-01

The archival data of 3C 345, a type 1 quasar at z = 0.5928, obtained with Suzaku and Swift/BAT are analysed. Though previous studies of this source applied only a simple broken power-law model, a heavily obscuring material is found to be required by considering Akaike information criteria. The application of the numerical torus model by Murphy & Yaqoob surprisingly reveals the existence of Compton thick type 2 nucleus with the line-of-sight hydrogen column density of the torus of NH = 1024.5 cm-2 and the inclination angle of θinc = 90°. However, this model fails to account for the Eddington ratio obtained with the optical observations by Gu et al. and Shen et al., or requires the existence of a supermassive black hole binary, which was suggested by Lobanov & Roland, thus this model is likely to be inappropriate for 3C 345. A partial covering ionized absorber model that accounts for absorption in 'hard excess' type 1 active galactic nuclei (AGNs) is also applied, and finds a Compton thick absorber with the column density of NH ≃ 1025 cm-2, the ionization parameter of log ξ ≳ 2 and the covering fraction of 75 per cent ≲ fc ≲ 85 per cent. Since this model obtains a black hole mass of log (MBH/M⊙) = 9.8, which is consistent with the optical observation by Gu et al., this model is likely to be the best-fitting model of this source. The results suggest that 3C 345 is the most distant and most obscured hard excess AGN at this time.

How to get cool in the heat: comparing analytic models of hot, cold, and cooling gas in haloes and galaxies with EAGLE

NASA Astrophysics Data System (ADS)

Stevens, Adam R. H.; Lagos, Claudia del P.; Contreras, Sergio; Croton, Darren J.; Padilla, Nelson D.; Schaller, Matthieu; Schaye, Joop; Theuns, Tom

2017-05-01

We use the hydrodynamic, cosmological EAGLE simulations to investigate how the hot gas in haloes condenses to form and grow galaxies. We select haloes from the simulations that are actively cooling and study the temperature, distribution and metallicity of their hot, cold and transitioning 'cooling' gas, placing these in the context of semi-analytic models. Our selection criteria lead us to focus on Milky Way-like haloes. We find that the hot-gas density profiles of the haloes form a progressively stronger core over time, the nature of which can be captured by a β profile that has a simple dependence on redshift. In contrast, the hot gas that will cool over a time-step is broadly consistent with a singular isothermal sphere. We find that cooling gas carries a few times the specific angular momentum of the halo and is offset in spin direction from the rest of the hot gas. The gas loses ˜60 per cent of its specific angular momentum during the cooling process, generally remaining greater than that of the halo, and it precesses to become aligned with the cold gas already in the disc. We find tentative evidence that angular-momentum losses are slightly larger when gas cools on to dispersion-supported galaxies. We show that an exponential surface density profile for gas arriving on a disc remains a reasonable approximation, but a cusp containing ˜20 per cent of the mass is always present, and disc scale radii are larger than predicted by a vanilla Fall & Efstathiou model. These scale radii are still closely correlated with the halo spin parameter, for which we suggest an updated prescription for galaxy formation models.

IMPETUS: consistent SPH calculations of 3D spherical Bondi accretion on to a black hole

NASA Astrophysics Data System (ADS)

Ramírez-Velasquez, J. M.; Sigalotti, L. Di G.; Gabbasov, R.; Cruz, F.; Klapp, J.

2018-07-01

We present three-dimensional calculations of spherically symmetric Bondi accretion on to a stationary supermassive black hole of mass 108 M⊙ within a radial range of 0.02-10 pc, using a modified version of the smoothed particle hydrodynamics GADGET-2 code, which ensures approximate first-order consistency (i.e. second-order accuracy) for the particle approximation. First-order consistency is restored by allowing the number of neighbours, nneigh, and the smoothing length, h, to vary with the total number of particles, N, such that the asymptotic limits nneigh → ∞ and h → 0 hold as N → ∞. The ability of the method to reproduce the isothermal (γ = 1) and adiabatic (γ = 5/3) Bondi accretion is investigated with increased spatial resolution. In particular, for the isothermal models, the numerical radial profiles closely match the Bondi solution, except near the accretor, where the density and radial velocity are slightly underestimated. However, as nneigh is increased and h is decreased, the calculations approach first-order consistency and the deviations from the Bondi solution decrease. The density and radial velocity profiles for the adiabatic models are qualitatively similar to those for the isothermal Bondi accretion. Steady-state Bondi accretion is reproduced by the highly resolved consistent models with a percent relative error of ≲ 1 per cent for γ = 1 and ˜9 per cent for γ = 5/3, with the adiabatic accretion taking longer than the isothermal case to reach steady flow. The performance of the method is assessed by comparing the results with those obtained using the standard GADGET-2 and GIZMO codes.

Hydrostatic Chandra X-ray analysis of SPT-selected galaxy clusters - I. Evolution of profiles and core properties

NASA Astrophysics Data System (ADS)

Sanders, J. S.; Fabian, A. C.; Russell, H. R.; Walker, S. A.

2018-02-01

We analyse Chandra X-ray Observatory observations of a set of galaxy clusters selected by the South Pole Telescope using a new publicly available forward-modelling projection code, MBPROJ2, assuming hydrostatic equilibrium. By fitting a power law plus constant entropy model we find no evidence for a central entropy floor in the lowest entropy systems. A model of the underlying central entropy distribution shows a narrow peak close to zero entropy which accounts for 60 per cent of the systems, and a second broader peak around 130 keV cm2. We look for evolution over the 0.28-1.2 redshift range of the sample in density, pressure, entropy and cooling time at 0.015R500 and at 10 kpc radius. By modelling the evolution of the central quantities with a simple model, we find no evidence for a non-zero slope with redshift. In addition, a non-parametric sliding median shows no significant change. The fraction of cool-core clusters with central cooling times below 2 Gyr is consistent above and below z = 0.6 (˜30-40 per cent). Both by comparing the median thermodynamic profiles, centrally biased towards cool cores, in two redshift bins, and by modelling the evolution of the unbiased average profile as a function of redshift, we find no significant evolution beyond self-similar scaling in any of our examined quantities. Our average modelled radial density, entropy and cooling-time profiles appear as power laws with breaks around 0.2R500. The dispersion in these quantities rises inwards of this radius to around 0.4 dex, although some of this scatter can be fitted by a bimodal model.

A low Lyman Continuum escape fraction of <10 per cent for extreme [O III] emitters in an overdensity at z ˜ 3.5

NASA Astrophysics Data System (ADS)

Naidu, Rohan P.; Forrest, Ben; Oesch, Pascal A.; Tran, Kim-Vy H.; Holden, Bradford P.

2018-07-01

Recent work has suggested that extreme [O III] emitting star-forming galaxies are important to reionization. Relatedly, [O III]/[O II] has been put forward as an indirect estimator of the Lyman Continuum (LyC) escape fraction (fesc) at z ≳ 4.5 when the opaque IGM renders LyC photons unobservable. Using deep archival U-band (VLT/VIMOS) imaging of a recently confirmed overdensity at z˜ 3.5, we calculate tight constraints on fesc for a sample (N = 73) dominated by extreme [O III] emitters. We find no LyC signal (f_esc^rel < 6.3^{+0.7}_{-0.7} per cent at 1σ) in a deep U-band stack of our sample (31.98 mag at 1σ). This constraint is in agreement with recent studies of star-forming galaxies spanning z ˜ 1-4 that have found very low average fesc. Despite the galaxies in our study having an estimated average rest-frame EW([O III]λ5007) ˜ 400 Å and [O III]/[O II] ˜ 4 from composite SED fitting, we find no LyC detection, which brings into question the potential of [O III]/[O II] as an effective probe of the LyC - a majority of LyC emitters have [O III]/[O II] > 3, but we establish here that [O III]/[O II] > 3 does not guarantee significant LyC leakage for a population. Since even extreme star-forming galaxies are unable to produce the f_esc˜ 10-15 per cent required by most theoretical calculations for star-forming galaxies to drive reionization, there must either be a rapid evolution of fesc between z˜ 3.5 and the epoch of reionization, or hitherto observationally unstudied sources [e.g. ultrafaint low-mass galaxies with log (M/M⊙) ˜ 7-8.5] must make an outsized contribution to reionization.

Preoperative imaging and prediction of oesophageal conduit necrosis after oesophagectomy for cancer.

PubMed

Lainas, P; Fuks, D; Gaujoux, S; Machroub, Z; Fregeville, A; Perniceni, T; Mal, F; Dousset, B; Gayet, B

2017-09-01

Oesophageal conduit necrosis following oesophagectomy is a rare but life-threatening complication. The present study aimed to assess the impact of coeliac axis stenosis on outcomes after oesophagectomy for cancer. The study included consecutive patients who had an Ivor Lewis procedure with curative intent for middle- and lower-third oesophageal cancer at two tertiary referral centres. All patients underwent preoperative multidetector CT with arterial phase to detect coeliac axis stenosis. The coeliac artery was classified as normal, with extrinsic stenosis due to a median arcuate ligament or with intrinsic stenosis caused by atherosclerosis. Some 481 patients underwent an Ivor Lewis procedure. Of these, ten (2·1 per cent) developed oesophageal conduit necrosis after surgery. Coeliac artery evaluation revealed a completely normal artery in 431 patients (91·5 per cent) in the group without conduit necrosis and in one (10 per cent) with necrosis (P < 0·001). Extrinsic stenosis of the coeliac artery due to a median arcuate ligament was found in two patients (0·4 per cent) without conduit necrosis and five (50 per cent) with necrosis (P < 0·001). Intrinsic stenosis of the coeliac artery was found in 11 (2·3 per cent) and eight (80 per cent) patients respectively (P < 0·001). Eight patients without (1·7 per cent) and five (50 per cent) with conduit necrosis had a single and thin left gastric artery (P < 0·001). This study suggests that oesophageal conduit necrosis after oesophagectomy for cancer may be due to pre-existing coeliac axis stenosis. © 2017 BJS Society Ltd Published by John Wiley & Sons Ltd.

Prognostic markers in feline hepatic lipidosis: a retrospective study of 71 cats.

PubMed

Kuzi, Sharon; Segev, Gilad; Kedar, Shay; Yas, Einat; Aroch, Itamar

2017-11-11

Feline hepatic lipidosis (HL) is a common, potentially life-threatening disease resulting from prolonged anorexia and increased catabolism. This retrospective study included cats diagnosed with HL based on liver cytology or histopathology (years 2004-2015), and aimed to identify clinical and laboratory parameters associated with mortality. The study included 71 cats (47 females and 24 males) and 85 control cats with non-HL diseases. Most HL cats (90 per cent) were mixed breed, neutered (70; 99 per cent), female (47; 66 per cent), indoor cats (56; 79 per cent), fed dry commercial diets (44 cats; 62 per cent), and with a median age of 7.5 years (range 1.5-16.0). Common primary conditions included gastrointestinal diseases, pancreatitis and cholangiohepatitis (31 cats; 44 per cent) and stressful events (14; 20 per cent). HL was idiopathic in 20 cats (28 per cent). The overall mortality was 38 per cent (27/71 cats). Older age, as well as dullness, weakness, ptyalism, hypoproteinaemia, hypoalbuminaemia, increased serum creatine kinase activity, hypocholesterolaemia and hepatic failure at presentation were significantly (P≤0.033) associated with mortality. The primary disease was unassociated with mortality. Worsening hypoalbuminaemia, hyperammonaemia, hyperbilirubinaemia, electrolyte disorders, and occurrence of cavitary effusions or hypotension during hospitalisation were significantly (P≤0.045) associated with mortality. A decrease of serum β-hydroxybutyrate during hospitalisation was significantly (P=0.01) associated with survival, likely reflecting improvement in the catabolic state. The identified risk factors may be therapeutic targets. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Compliance and use of the World Health Organization checklist in U.K. operating theatres.

PubMed

Pickering, S P; Robertson, E R; Griffin, D; Hadi, M; Morgan, L J; Catchpole, K C; New, S; Collins, G; McCulloch, P

2013-11-01

The World Health Organization (WHO) Surgical Safety Checklist is reported to reduce surgical morbidity and mortality, and is mandatory in the U.K. National Health Service. Hospital audit data show high compliance rates, but direct observation suggests that actual performance may be suboptimal. For each observed operation, WHO time-out and sign-out attempts were recorded, and the quality of the time-out was evaluated using three measures: all information points communicated, all personnel present and active participation. Observation of WHO checklist performance was conducted for 294 operations, in five hospitals and four surgical specialties. Time-out was attempted in 257 operations (87.4 per cent) and sign-out in 26 (8.8 per cent). Within time-out, all information was communicated in 141 (54.9 per cent), the whole team was present in 199 (77.4 per cent) and active participation was observed in 187 (72.8 per cent) operations. Surgical specialty did not affect time-out or sign-out attempt frequency (P = 0.453). Time-out attempt frequency (range 42-100 per cent) as well as all information communicated (15-83 per cent), all team present (35-90 per cent) and active participation (15-93 per cent) varied between hospitals (P < 0.001 for all). Meaningful compliance with the WHO Surgical Safety Checklist is much lower than indicated by administrative data. Sign-out compliance is generally poor, suggesting incompatibility with normal theatre work practices. There is variation between hospitals, but consistency across studied specialties, suggesting a need to address organizational culture issues. © 2013 British Journal of Surgery Society Ltd. Published by John Wiley & Sons Ltd.

Negative self-perception of smile associated with malocclusions among Brazilian adolescents.

PubMed

Moura, Cristiano; Cavalcanti, Alessandro Leite; Gusmão, Estela Santos; Soares, Renata de Souza Coelho; Moura, Fabiana Torres Cavalcante; Santillo, Patrícia Morgana Hordonho

2013-08-01

This study estimated the prevalence of negative self-perception of smile because of occlusion abnormalities and investigated their association according to standard clinical criteria. The sample consisted of 1290 randomly selected Brazilian adolescent boys and girls aged 12-16 years. The outcome of interest was dissatisfaction with smile, and data were collected using a standardized questionnaire. Occlusion characteristics were assessed using the dental aesthetic index (DAI). The other study variables were gender, age, and use of dental services. A chi-square test and Poisson multiple regression were used for statistical analysis. Of the 1290 students interviewed and examined, 539 (41.8 per cent) were dissatisfied with their smile; of these, 373 (69.2 per cent) assigned their dissatisfaction to the presence of an occlusal abnormality, and 166 (30.8 per cent) reported reasons other than occlusal abnormalities for their negative self-perception of their smile. In multivariate analysis, the following variables were associated with the outcome of interest: maxillary anterior irregularity [prevalence ratio (PR) = 1.40; 95 per cent confidence interval (CI) = 1.29-1.80], incisal spacing (PR = 1.37; 95 per cent CI = 1.19-1.57), vertical open bite (PR = 1.34; 95 per cent CI = 1.15-1.55), mandibular anterior irregularity (PR = 1.29; 95 per cent CI = 1.14-1.46), permanent anterior teeth missing (PR = 1.21; 95 per cent CI = 1.05-1.39), and incisal diastema (PR = 1.14; 95 per cent CI = 1.01-1.31). The negative self-perception of smile was statistically associated with severity of occlusal disorders according to the DAI scores, which suggests that self-perception should be used together with standard clinical criteria when decisions about orthodontic treatments are made in public health care systems.

Do doctors need statistics? Doctors' use of and attitudes to probability and statistics.

PubMed

Swift, Louise; Miles, Susan; Price, Gill M; Shepstone, Lee; Leinster, Sam J

2009-07-10

There is little published evidence on what doctors do in their work that requires probability and statistics, yet the General Medical Council (GMC) requires new doctors to have these skills. This study investigated doctors' use of and attitudes to probability and statistics with a view to informing undergraduate teaching.An email questionnaire was sent to 473 clinicians with an affiliation to the University of East Anglia's Medical School.Of 130 respondents approximately 90 per cent of doctors who performed each of the following activities found probability and statistics useful for that activity: accessing clinical guidelines and evidence summaries, explaining levels of risk to patients, assessing medical marketing and advertising material, interpreting the results of a screening test, reading research publications for general professional interest, and using research publications to explore non-standard treatment and management options.Seventy-nine per cent (103/130, 95 per cent CI 71 per cent, 86 per cent) of participants considered probability and statistics important in their work. Sixty-three per cent (78/124, 95 per cent CI 54 per cent, 71 per cent) said that there were activities that they could do better or start doing if they had an improved understanding of these areas and 74 of these participants elaborated on this. Themes highlighted by participants included: being better able to critically evaluate other people's research; becoming more research-active, having a better understanding of risk; and being better able to explain things to, or teach, other people.Our results can be used to inform how probability and statistics should be taught to medical undergraduates and should encourage today's medical students of the subjects' relevance to their future careers. Copyright 2009 John Wiley & Sons, Ltd.

Dogs attending primary-care practice in England with clinical signs suggestive of Chiari-like malformation/syringomyelia.

PubMed

Sanchis-Mora, S; Pelligand, L; Thomas, C L; Volk, H A; Abeyesinghe, S M; Brodbelt, D C; Church, D B; Thomson, P C; McGreevy, P D; O'Neill, D G

2016-10-29

Chiari-like malformation/syringomyelia (CM/SM) in dogs describes a developmental disorder that can cause pain and reduced quality of life. This retrospective study aimed to report the period prevalence, clinical signs and risk factors for diagnosis of symptomatic CM/SM in the veterinary primary-care setting using a cross-sectional design. The study population included all dogs within the VetCompass Programme (September 1, 2009-June 13, 2014). Overall, the period prevalence of symptomatic CM/SM was 0.05 per cent (95 per cent CI 0.04 per cent to 0.06 per cent) for all breeds. The period prevalence in the Cavalier King Charles Spaniel (CKCS) was 1.6 per cent (95 per cent CI 1.2 to 2.06). Other breeds at increased odds included the King Charles Spaniel (KCS), Affenpinscher, Chihuahua and Pomeranian. Insured dogs had 4.6 times the odds (95 per cent CI 2.95 to 7.17) of having a diagnosis of CM/SM compared with uninsured dogs. Pain was the most commonly associated clinical sign (67 dogs, 72 per cent). Analgesics were prescribed to 72 (77.4 per cent) of the symptomatic dogs. Despite its low overall period prevalence, the high proportion of affected dogs identified with chronic pain suggests a significant welfare issue. Financial implications could impede the diagnostic process and lead to underestimation of the true prevalence. This study may help to inform clinicians about the clinical relevance and the need for improved awareness of clinical signs, particularly in high-risk breeds, to optimise the management of CM/SM in primary-care practice. British Veterinary Association.

Use of Landsat data to evaluate lesser prairie chicken habitats in western Oklahoma

USGS Publications Warehouse

Cannon, R. W.; Knopf, Fritz L.; Pettinger, Lawrence R.

1982-01-01

Landsat digital data were used to evaluate lesser prairie chicken (Tympanuchus pallidicinctus) habitats in western Oklahoma. Data for 7 (4,144 ha) study areas, 4 in shinnery oak (Quercus havardii), and 3 in sand sagebrush (Artemisia filifolia) rangeland, were analyzed using the Interactive Digital Image Manipulation System at the EROS Center. In shinnery oak rangeland, density of displaying males was correlated positively with percentage of area in grassland classes and negatively correlated with the percentage in brushland classes. In sand sagebrush rangeland, density of displaying males was negatively, but not significantly correlated with percentage of area in bare soil and grassland classes, and positively, but not significantly correlated with percentage of area in brushland classes. The trends found between density of displaying males and the Landsat-generated resource classes closely parallel similar relationships found with field sampling techniques. Analysis of the Landsat digital data for this study cost 13.8 cents/ha. Because larger areas could have been analyzed with the same digital data, the unit cost for analysis would decline with increasingly larger areas.

Serological responses of adult dogs to revaccination against distemper, parvovirus and rabies.

PubMed

Ottiger, H-P; Neimeier-Förster, M; Stärk, K D C; Duchow, K; Bruckner, L

2006-07-01

Serum antibody titres to canine distemper virus (CDV), canine parvovirus (CPV) and rabies were measured in dogs that had not been revaccinated annually and compared with the titres in a control group of regularly vaccinated animals; 83 per cent (171 of 207) of the dogs vaccinated against CDV one or more years earlier had serum neutralising antibody titres equal to or greater than 16; 64 per cent (136 of 213) of the dogs vaccinated against CPV one or more years earlier had haemagglutination inhibiting titres equal to or greater than 80; and 59 per cent (46 of 78) of the dogs vaccinated against rabies two or more years earlier had serum neutralising antibody titres equal to or greater than 0.5 iu/ml. Three weeks after a single booster vaccination the dogs' antibody titres against CDV had increased above the threshold level in 94 per cent of the dogs, against CPV in 68 per cent, and against rabies in 100 per cent.

Extended family households among children in the United States: Differences by race/ethnicity and socio-economic status.

PubMed

Cross, Christina J

2018-07-01

This study uses nationally representative longitudinal data from the Panel Study of Income Dynamics, to examine the prevalence and predictors of extended family households among children in the United States and to explore variation by race/ethnicity and socio-economic status (SES). Findings suggest that extended family households are a common living arrangement for children, with 35 per cent of youth experiencing this family structure before age 18. Racial/ethnic and SES differences are substantial: 57 per cent of Black and 35 per cent of Hispanic children ever live in an extended family, compared with 20 per cent of White children. Further, 47 per cent of children whose parents did not finish high school spend time in an extended family, relative to 17 per cent of children whose parents earned a bachelor's degree or higher. Models of predictors show that transitions into extended families are largely a response to social and economic needs.

Motor vehicle-related burns: a review of 107 cases.

PubMed

Papaevangelou, J; Batchelor, J S; Roberts, A H

1995-02-01

Motor vehicles are a major cause of morbidity and mortality. Burn injuries sustained from motor vehicles form a small but important subgroup. The authors have reviewed the case notes of 107 patients with motor vehicle-related burns over a 13-year period. The age ranged from 18 months to 65 years and the male to female ratio was 4:1. The mechanisms of injury were variable, although four major categories could be identified. These accounted for 83 per cent of the cases. Car fires following road traffic accidents was the largest group accounting for 48.5 per cent of cases. The remaining three groups were: motorcycle-related burns following road traffic accidents (6.5 per cent of cases), garage fire-related burns (15 per cent of cases) and car radiator-related burns (13 per cent of cases). Garage fire-related burns had the highest mortality of the four groups (25 per cent). This study demonstrated that garage fire burns are an important subgroup of motor vehicle-related burns.

Genetic influence on age at first birth of female twins born in the UK, 1919-68.

PubMed

Tropf, Felix C; Barban, Nicola; Mills, Melinda C; Snieder, Harold; Mandemakers, Jornt J

2015-01-01

Using a sample of monozygotic (945, 42 per cent) and dizygotic (1,329, 58 per cent) twin pairs born 1919-68 in the UK, we applied innovative tobit models to investigate genetic and environmental influences on age at first birth (AFB). We found that a substantial part (40 per cent) of the variation in AFB is caused by latent family characteristics. Genetic dispositions (26 per cent) play a more important role than the shared environment of siblings (14 per cent), with the non-shared environment/measurement error having the strongest influence (60 per cent). Like previous studies, this study reveals marked changes in estimates over time, and supports the idea that environmental constraints (war or economic crisis) suppress and normative freedom (sexual revolution) promotes the activation of genetic predispositions that affect fertility. We show that the exclusion of censored information (i.e., on the childless) by previous studies biased their results.

[Reappearance of soft chancre: comments on the current epidemic in Paris (author's transl)].

PubMed

Civatte, J; Belaich, S; Bonvalet, D; Vallet, C; Broissin, M

1980-01-01

A total of 678 cases of soft chancre were treated in one hospital between 1973 and 1979. The majority of the patients were males (97 p. cent), and most of them came originally from Maghreb or Black Africa. Contamination was from prostitution (61 p. cent) or chance acquaintances (29 p. cent). The genital ulceration was often clinically atypical, frequently syphiloid; pain was present in only 59 p. cent of cases, and adenopathy, noted in 63 p. cent of patients, had the appearance of an inflammatory bubo in only 23 p. cent. The present high frequency of soft chancres, and their misleading clinical characteristics, makes it sometimes difficult to establish the clinical differential diagnosis from syphilitic chancre, but confirmation of the latter is supplied by direct examination and culture to search for Ducreys bacillus, this being indispensable for establishing the correct diagnosis. Treatment with sulfamethoxazole trimethopin or streptomycin prevents complications and cures the affection in one or two weeks.

Theoretical and Experimental Beam Plasma Physics (TEBPP)

NASA Technical Reports Server (NTRS)

Roberts, W. T.

1985-01-01

The theoretical and experimental beam plasma physics (TEBPP) consists of a package of five instruments to measure electric and magnetic fields, plasma density and temperature, neutral density, photometric emissions, and energetic particle spectra during firings of the particle injector (SEPAC) electron beam. The package is deployed on a maneuverable boom (or RMS) and is used to measure beam characteristics and induced perturbations in the near field ( 10 m) and mid field (10 m to 100 m) along the electron beam. The TEBPP package will be designed to investigate induced oscillations and induced electromagnetic mode waves, neutral and ion density and temperature effects, and beam characteristics as a function of axial distance.

Theoretical and Experimental Beam Plasma Physics (TEBPP)

NASA Technical Reports Server (NTRS)

Roberts, B.

1986-01-01

The theoretical and experimental beam plasma physics (TEBPP) consists of a package of five instruments to measure electric and magnetic fields, plasma density and temperature, neutral density, photometric emissions, and energetic particle spectra during firings of the particle injector (SEPAC) electron beam. The package is developed on a maneuverable boom (or RMS) and is used to measure beam characteristics and induced perturbations field ( 10 m) and mid field ( 10 m to 100 m) along the electron beam. The TEBPP package will be designed to investigate induced oscillations and induced electromagnetic mode waves, neutral and ion density and temperature effects, and beam characteristics as a function of axial distance.

Evaluation of cervical spine fracture in the elderly: can we trust our physical examination?

PubMed

Goode, Terral; Young, Andrew; Wilson, Sean P; Katzen, Judith; Wolfe, Luke G; Duane, Therese M

2014-02-01

The purpose of this trial was to compare National Emergency X-Radiography Utilization Study (NEXUS) criteria (NC) with computed tomography (CT) as the gold standard to evaluate cervical spine (C-spine) fractures in elderly blunt trauma patients. We prospectively compared adult blunt trauma patients 65 years or older (E) with younger than 65 years (NE), evaluating the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of NC compared with CT in these two cohorts. A total of 2785 blunt trauma patients were included of whom 320 were E (average age, 75 years) and 2465 were NE (average age, 36 years). Incidence of C-spine fracture was 12.8 per cent (E) versus 7.4 per cent (NE) (P = 0.002). Age was an independent predictor of fracture (P = 0.01). NC had a sensitivity of 65.9 per cent in E and PPV of 19.3 per cent in E (P = 0.001) versus a sensitivity of 84.2 per cent in NE and PPV of 10.6 per cent (P < 0.0001). The specificity was 59.5 per cent for E versus 42.6 per cent for NE (NPV, 92.2% E vs 97.1% NE). This study suggests that NEXUS criteria are not an appropriate assessment tool when applied to severe blunt trauma patients, particularly in the elderly population who had more missed injures than their younger counterparts. CT should be used in all blunt trauma patients regardless of whether they meet NEXUS criteria.

Infant mortality and undernutrition in the squatter settlements of Karachi.

PubMed

Thaver, I H; Ebrahim, G J; Richardson, R

1990-06-01

The socio-demographic and biological processes contributing to infant mortality and undernourishment were studied in five urban squatter settlements of Karachi. All those families who had experienced an infant death in the past 2 years (N = 106) were recruited into the study. Comparative children were selected by random numbers with geographical matching from families with at least one live infant and without a history of infant deaths in the past 2 years. The comparison children were weighed and those found underweight (27 per cent) were studied for the presence of risk factors. Forty-one per cent of all deaths were in the neonatal period, and in 47 per cent of cases deaths had occurred in infants with a birth order of 5 and above. Age, duration of breast feeding, birth interval, and the live/dead status of the previous sibling were significant biological variables accounting for 23 per cent of the variance for survival. Socio-economic status accounted for 22 per cent of the variance and health-seeking behaviour (antenatal care, immunization, etc.) for 28 per cent. Sixty-eight per cent of those underweight were more than 6 months old. Age, female sex, birth interval less than 24 months, duration of breast feeding, adolescent mother, alive/dead status of the previous child were significant influences accounting for 12 per cent of the variance. Socio-economic status and health seeking behaviour were also important determinants, but not to the same extent as in the case of infant death.

Anaemia in pet rabbits: causes, severity and reticulocyte response.

PubMed

Dettweiler, Alexandra; Klopfleisch, Robert; Müller, Kerstin

2017-12-16

The objective of the study was to determine the causes and the severity of anaemia in pet rabbits ( Oryctolagus cuniculus ), to classify anaemia and to compare the reticulocyte counts from healthy and anaemic rabbits. Over a time period of 11 years (2000-2011) a retrospective and prospective study of 223 pet rabbits was performed. Based on the clinic's own reference range for healthy pet rabbits (packed cell volume [PCV] levels 0.33-0.45 l/l), animals with a PCV level below 0.33 l/l were considered anaemic. Anaemia was mostly caused by inflammation (65/223, 29 per cent) and bleeding (54/223, 24 per cent). Seven per cent (15/223) of the rabbits suffered from renal diseases and one rabbit got diagnosed with haemolysis caused by liver lobe torsion. In 14 per cent (32/223) of the rabbits more than one underlying pathomechanism, like inflammation and bleeding, was diagnosed as possible cause of anaemia. In 25 per cent (56/223) of the anaemic rabbits no cause was found. Most anaemias were mild (156/223, 70 per cent). Moderate (43/223, 19 per cent) or severe (24/223, 11 per cent) anaemia was diagnosed more rarely. Anaemic rabbits showed similar reticulocyte counts to healthy rabbits with no significant difference. Therefore, a differentiation of regenerative and non-regenerative anaemia was not possible. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Zoonotic bacteria and parasites found in raw meat-based diets for cats and dogs.

PubMed

van Bree, Freek P J; Bokken, Gertie C A M; Mineur, Robin; Franssen, Frits; Opsteegh, Marieke; van der Giessen, Joke W B; Lipman, Len J A; Overgaauw, Paul A M

2018-01-13

Feeding raw meat-based diets (RMBDs) to companion animals has become increasingly popular. Since these diets may be contaminated with bacteria and parasites, they may pose a risk to both animal and human health. The purpose of this study was to test for the presence of zoonotic bacterial and parasitic pathogens in Dutch commercial RMBDs. We analysed 35 commercial frozen RMBDs from eight different brands. Escherichia coli serotype O157:H7 was isolated from eight products (23 per cent) and extended-spectrum beta-lactamases-producing E coli was found in 28 products (80 per cent). Listeria monocytogenes was present in 19 products (54 per cent), other Listeria species in 15 products (43 per cent) and Salmonella species in seven products (20 per cent). Concerning parasites, four products (11 per cent) contained Sarcocystis cruzi and another four (11 per cent) S tenella In two products (6 per cent) Toxoplasma gondii was found. The results of this study demonstrate the presence of potential zoonotic pathogens in frozen RMBDs that may be a possible source of bacterial infections in pet animals and if transmitted pose a risk for human beings. If non-frozen meat is fed, parasitic infections are also possible. Pet owners should therefore be informed about the risks associated with feeding their animals RMBDs. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Variations in locoregional therapy in postmenopausal patients with early breast cancer treated in different countries.

PubMed

van Nes, J G H; Seynaeve, C; Jones, S; Markopoulos, C; Putter, H; van de Velde, C J H; Hasenburg, A; Rea, D W; Vannetzel, J-M; Dirix, L; Hozumi, Y; Kerin, M J; Kieback, D G; Meershoek-Klein Kranenbarg, W M; Hille, E T M; Nortier, J W R

2010-05-01

The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial is an international randomized trial evaluating the efficacy and safety of exemestane, alone or following tamoxifen. The large number of patients already recruited offered the opportunity to explore locoregional treatment practices between countries. Patients were enrolled in Belgium, France, Germany, Greece, Ireland, Japan, the Netherlands, the UK and the USA. The core protocol had minor differences in eligibility criteria between countries, reflecting variations in national guidelines and practice regarding adjuvant endocrine therapy. Between 2001 and 2006, 9779 patients of mean(s.d.) age 64(9) years were randomized. Some 58.4 per cent had T1 tumours (range between countries 36.8-75.9 per cent; P < 0.001) and 47.3 per cent were axillary node positive (range 25.9-84.6 per cent; P < 0.001). Independent factors for type of breast surgery were country, age, tumour status and calendar year of surgery. After breast-conserving surgery, radiotherapy was given to 93.2 per cent of patients, 86.0 per cent in the USA and 100 per cent in France. Axillary lymph node dissection was performed in 82.0 (range 74.6-99.1) per cent. Despite international consensus guidelines, wide global variations were observed in treatment practices of early breast cancer. There should be further efforts to optimize locoregional treatment for breast cancer worldwide. Copyright 2010 British Journal of Surgery Society Ltd.

A survey of Campylobacter and other bacterial contaminants of pre-market chicken and retail poultry and meats, King County, Washington.

PubMed Central

Harris, N V; Thompson, D; Martin, D C; Nolan, C M

1986-01-01

As part of a larger study to determine the flow of Campylobacter and Salmonella from food animals to humans during 1982-83, 1,936 swabs were collected for bacteriologic study from pre-market chickens, retail poultry, and other retail meats as well as from equipment and work surfaces used to process such foods. Of the 297 samples collected in a poultry processing plant, 56.6 per cent were positive for Campylobacter jejuni/coli (CJC), as were 23.1 per cent of the 862 retail chicken, and 17.2 per cent of the 29 retail game hen samples. CJC was found infrequently in retail turkey, pork, and beef samples. Contamination of retail and pre-market chicken with CJC appeared to increase as the week progressed, and in pre-market chicken, later in the day. Less than 5 per cent of the retail samples of poultry, beef, and pork were found to contain Yersinia or Salmonella. However, Salmonella was cultured from 14.8 per cent of the swabs taken from the processing plant with 68 per cent of 44 Salmonellas being isolated concurrently with CJC. Tetracycline resistance which was plasmid-mediated was the most common antibiotic resistance observed, and was carried by 23.8 per cent of all CJC isolates. Overall, 38.8 per cent of all CJC isolates were resistant to ampicillin, erythromycin, streptomycin, or tetracycline, either singly or in combination. PMID:3953916

Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

PubMed Central

Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

2016-01-01

Local surface charge density of lipid membranes influences membrane–protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values. PMID:27561322

Theoretical prediction of the impact of Auger recombination on charge collection from an ion track

NASA Technical Reports Server (NTRS)

Edmonds, Larry D.

1991-01-01

A recombination mechanism that significantly reduces charge collection from very dense ion tracks in silicon devices was postulated by Zoutendyk et al. The theoretical analysis presented here concludes that Auger recombination is such a mechanism and is of marginal importance for higher density tracks produced by 270-MeV krypton, but of major importance for higher density tracks. The analysis shows that recombination loss is profoundly affected by track diffusion. As the track diffuses, the density and recombination rate decrease so fast that the linear density (number of electron-hole pairs per unit length) approaches a non-zero limiting value as t yields infinity. Furthermore, the linear density is very nearly equal to this limiting value in a few picoseconds or less. When Auger recombination accompanies charge transport processes that have much longer time scales, it can be simulated by assigning a reduced linear energy transfer to the ion.

Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

NASA Astrophysics Data System (ADS)

Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

2016-08-01

Local surface charge density of lipid membranes influences membrane-protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values.

Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy.

PubMed

Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

2016-08-26

Local surface charge density of lipid membranes influences membrane-protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values.

Geometric characterization and simulation of planar layered elastomeric fibrous biomaterials

DOE PAGES

Carleton, James B.; D’Amore, Antonio; Feaver, Kristen R.; ...

2014-10-13

Many important biomaterials are composed of multiple layers of networked fibers. While there is a growing interest in modeling and simulation of the mechanical response of these biomaterials, a theoretical foundation for such simulations has yet to be firmly established. Moreover, correctly identifying and matching key geometric features is a critically important first step for performing reliable mechanical simulations. This paper addresses these issues in two ways. First, using methods of geometric probability, we develop theoretical estimates for the mean linear and areal fiber intersection densities for 2-D fibrous networks. These densities are expressed in terms of the fiber densitymore » and the orientation distribution function, both of which are relatively easy-to-measure properties. Secondly, we develop a random walk algorithm for geometric simulation of 2-D fibrous networks which can accurately reproduce the prescribed fiber density and orientation distribution function. Furthermore, the linear and areal fiber intersection densities obtained with the algorithm are in agreement with the theoretical estimates. Both theoretical and computational results are compared with those obtained by post-processing of scanning electron microscope images of actual scaffolds. These comparisons reveal difficulties inherent to resolving fine details of multilayered fibrous networks. Finally, the methods provided herein can provide a rational means to define and generate key geometric features from experimentally measured or prescribed scaffold structural data.« less

New Zealand optometrists 2006: demographics, working arrangements and hours worked.

PubMed

Frederikson, Lesley G; Chamberlain, Kerry; Sangster, Andrew J

2008-07-01

Optometry is a regulated health profession in NZ, with limited student places. With 650 registered optometrists in 2005, the optometrist to population ratio was 1 : 6,291 with no apparent national shortage. If optometrists registered in NZ do not actually live there, a workforce shortage is possible. This paper presents findings from the New Zealand Association of Optometrists 2006 workforce survey of members, which aimed to profile the NZ optometric workforce and to explore factors relating to workforce capacity, job stress and future planning. A questionnaire was developed to collect information on employment status, hours worked and gender distribution of optometrists in New Zealand. It was circulated to 530 active members of the NZ Association of Optometrists representing 86 per cent of the available optometrists. Direct comparisons with the Australian optometric workforce numbers were also undertaken. Of the 243 respondents, 129 (53 per cent) were male. The median age of all respondents was 39 years (46 for males and 34 for females) and 75 per cent of the respondents were aged younger than 50 years. Fifty per cent had practised 15 years or less. Ten per cent of respondents had 'time-out' during their career and this was significantly more likely for females. Nearly half the respondents were self-employed (46 per cent) and eight per cent worked as locums. Part-time employees were more likely to be female and males were more likely to be in full-time self-employment. Half the group was under 40 (51 per cent), which accounted for 86 per cent of the full-time salaried arrangements. Those aged 30 to 39 included 52 per cent of the total part-time salaried workers. The average working week was 34 hours for women and 39 hours for men; the median was 40 hours for both groups. In the typical working week, 80 per cent of an optometrist's time was spent consulting with patients and five per cent was patient-related paperwork. The distribution of work arrangements was remarkably similar among New Zealand optometrists, New Zealand GPs and Australian optometrists. In 2006, there were 619 optometrists assessed as working in New Zealand. This equated to 544 EFTOs and a ratio of EFTO to population of 1 : 7,517. The New Zealand optometric workforce in 2006 was sufficient to meet the overall population needs. One-third of optometrists chose to work part-time and the proportion of female optometrists has increased over the past 15 years. In the face of expected increasing demand for optometric services, a targeted expansion of the workforce appears desirable.

Theoretical Evaluation of Crosslink Density of Chain Extended Polyurethane Networks Based on Hydroxyl Terminated Polybutadiene and Butanediol and Comparison with Experimental Data

NASA Astrophysics Data System (ADS)

Sekkar, Venkataraman; Alex, Ancy Smitha; Kumar, Vijendra; Bandyopadhyay, G. G.

2018-01-01

Polyurethane networks between hydroxyl terminated polybutadiene (HTPB) and butanediol (BD) were prepared using toluene diisocyanate (TDI) as the curative. HTPB and BD were taken at equivalent ratios viz.: 1:0, 1:1, 1:2, 1:4, and 1:8. Crosslink density (CLD) was theoretically calculated using α-model equations developed by Marsh. CLD for the polyurethane networks was experimentally evaluated from equilibrium swell and stress-strain data. Young's modulus and Mooney-Rivlin approaches were adopted to calculate CLD from stress-strain data. Experimentally obtained CLD values were enormously higher than theoretical values especially at higher BD/HTPB equivalent ratios. The difference in the theoretical and experimental values for CLD was explained in terms of local crystallization due to the formation of hard segments and hydrogen bonded interactions.

A density functional theory study on the thermodynamic and dynamic properties of anthraquinone analogue cathode materials for rechargeable lithium ion batteries.

PubMed

Yang, Shu-Jing; Qin, Xiao-Ya; He, Rongxing; Shen, Wei; Li, Ming; Zhao, Liu-Bin

2017-05-21

Organic redox compounds have become the emerging electrode materials for rechargeable lithium ion batteries. The high electrochemical performance provides organic electrode materials with great opportunities to be applied in electric energy storage devices. Among the different types of organic materials, conjugated carbonyl compounds are the most promising type at present, because only they can simultaneously achieve, high energy density, high cycling stability, and high power density. In this research, a series of heteroatom substituted anthraquinone (AQ) derivatives were designed theoretically so that the high theoretical capacity of AQ remained. The discharge and charge mechanism as well as the thermodynamic and dynamic properties of AQ and its derivatives were investigated using first-principles density functional theory. Using heteroatom substitution, both the thermodynamic and dynamic properties of AQ as cathode materials could be largely improved. Among these conjugated carboxyl compounds, BDOZD and BDIOZD with a simultaneously high theoretical capacity and high working potential exhibit the largest energy density of about 780 W h kg -1 , which is 41% larger than that of AQ. The PQD with the smallest value of λ gives the largest charge transfer rate constant, which is about four times as large as the prototype molecule, AQ. The most interesting finding is that the lithium ion transfer plays a very important role in influencing both the discharge potential and electrochemical charge transfer rate. The present study illustrates that theoretical calculations provide a highly effective way to discover potential materials for use with rechargeable lithium ion batteries.

Simultaneously constraining the astrophysics of reionisation and the epoch of heating with 21CMMC

NASA Astrophysics Data System (ADS)

Greig, Bradley; Mesinger, Andrei

2018-05-01

We extend our MCMC sampler of 3D EoR simulations, 21CMMC, to perform parameter estimation directly on light-cones of the cosmic 21cm signal. This brings theoretical analysis one step closer to matching the expected 21-cm signal from next generation interferometers like HERA and the SKA. Using the light-cone version of 21CMMC, we quantify biases in the recovered astrophysical parameters obtained from the 21cm power spectrum when using the co-eval approximation to fit a mock 3D light-cone observation. While ignoring the light-cone effect does not bias the parameters under most assumptions, it can still underestimate their uncertainties. However, significant biases (~few - 10 σ) are possible if all of the following conditions are met: (i) foreground removal is very efficient, allowing large physical scales (k ~ 0.1 Mpc-1) to be used in the analysis; (ii) theoretical modelling is accurate to ~10 per cent in the power spectrum amplitude; and (iii) the 21cm signal evolves rapidly (i.e. the epochs of reionisation and heating overlap significantly

Ecological relationships of breeding blue-winged teal to prairie potholes

USGS Publications Warehouse

Drewien, R.C.; Springer, P.F.

1969-01-01

Ecology of breeding blue-winged teal (Anas discors) was studied on the Waubay Study Area in Day County, South Dakota, in 1965 and 1966. Breeding pair use of the wetland habitat and importance of Type 1 ponds in the wetland complex were evaluated. Changes in breeding pair densities and wetland habitat conditions on the study area were compared for the 16-year period, 1950-66.Blue-winged teal pair densities of 30.7 and 33.0 per square mile in 1965 and 1966, respectively, were above the 16-year average from 1950 to 1966 and near the maximum for this period. Blue-winged teal comprised 46.7 per cent of the waterfowl breeding population in 1965 and 51.7 per cent in 1966. Number of water areas per square mile through mid-spring 1965 was comparable to the average for the 16-year period, whereas during late spring 1965 and throughout the 1966 spring breeding seasons the number of water areas increased to near optimum conditions.Annual breeding-pair densities from 1950 to 1966 appeared to be largely influenced by water conditions, and pair-density fluctuations resulted from changes in number of wet ponds from late April through mid-May. Variations in water conditions after this period did not appear to have as great an effect on numbers of breeding teal.Use of wetland habitat by pairs changed throughout the spring breeding seasons. During the post-arrival period, teal congregated on larger wetlands. With onset of egg-laying, pairs dispersed into ponds throughout the wetland complex to establish breeding home ranges. Other factors that influenced changes in habitat use included: 1) pond type and size, 2) breeding cycle phenology, 3) availability of wet ponds, and 4) land use. Number of blue-winged teal pairs per unit area of water was highest in 1965 and 1966 on Type 1B ponds, followed in decreasing order by Types 3, 1A, and 4 and 5. Greater use of Type 1B ponds was probably related to larger ratio of edge or shore line to unit area of water. Interspersion of many small wetlands throughout the breeding habitat provided for maximum pair dispersal during egg-laying and early incubation stages of the reproductive cycle.

Measuring environmental sustainability in agriculture: A composite environmental impact index approach.

PubMed

Sabiha, Noor-E; Salim, Ruhul; Rahman, Sanzidur; Rola-Rubzen, Maria Fay

2016-01-15

The present study develops a composite environmental impact index (CEII) to evaluate the extent of environmental degradation in agriculture after successfully validating its flexibility, applicability and relevance as a tool. The CEII tool is then applied to empirically measure the extent of environmental impacts of High Yield Variety (HYV) rice cultivation in three districts of north-western Bangladesh for a single crop year (October, 2012-September, 2013). Results reveal that 27 to 69 per cent of the theoretical maximum level of environmental damage is created due to HYV rice cultivation with significant regional variations in the CEII scores, implying that policy interventions are required in environmentally critical areas in order to sustain agriculture in Bangladesh. Copyright © 2015 Elsevier Ltd. All rights reserved.

VizieR Online Data Catalog: Massive early-type galaxies (Buitrago+, 2013)

NASA Astrophysics Data System (ADS)

Buitrago, F.; Trujillo, I.; Conselice, C. J.; Haussler, B.

2013-08-01

Present-day massive galaxies are composed mostly of early-type objects. It is unknown whether this was also the case at higher redshifts. In a hierarchical assembling scenario the morphological content of the massive population is expected to change with time from disc-like objects in the early Universe to spheroid-like galaxies at present. In this paper we have probed this theoretical expectation by compiling a large sample of massive (Mstellar>=1011h-270M⊙) galaxies in the redshift interval 0

On the impact of helium abundance on the Cepheid period-luminosity and Wesenheit relations and the distance ladder

NASA Astrophysics Data System (ADS)

Carini, R.; Brocato, E.; Raimondo, G.; Marconi, M.

2017-08-01

This work analyses the effect of the helium content on synthetic period-luminosity relations (PLRs) and period-Wesenheit relations (PWRs) of Cepheids and the systematic uncertainties on the derived distances that a hidden population of He-enhanced Cepheids may generate. We use new stellar and pulsation models to build a homogeneous and consistent framework to derive the Cepheid features. The Cepheid populations expected in synthetic colour-magnitude diagrams of young stellar systems (from 20 to 250 Myr) are computed in several photometric bands for Y = 0.25 and 0.35, at a fixed metallicity (Z = 0.008). The PLRs appear to be very similar in the two cases, with negligible effects (few per cent) on distances, while PWRs differ somewhat, with systematic uncertainties in deriving distances as high as ˜ 7 per cent at log P < 1.5. Statistical effects due to the number of variables used to determine the relations contribute to a distance systematic error of the order of few percent, with values decreasing from optical to near-infrared bands. The empirical PWRs derived from multiwavelength data sets for the Large Magellanic Cloud (LMC) is in a very good agreement with our theoretical PWRs obtained with a standard He content, supporting the evidence that LMC Cepheids do not show any He effect.

31 CFR 82.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Definitions. 82.3 Section 82.3 Money and Finance: Treasury Regulations Relating to Money and Finance MONETARY OFFICES, DEPARTMENT OF THE TREASURY 5-CENT AND ONE-CENT COIN REGULATIONS § 82.3 Definitions. (a) 5-cent coin of the United States...

31 CFR 82.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Definitions. 82.3 Section 82.3 Money and Finance: Treasury Regulations Relating to Money and Finance MONETARY OFFICES, DEPARTMENT OF THE TREASURY 5-CENT AND ONE-CENT COIN REGULATIONS § 82.3 Definitions. (a) 5-cent coin of the United States...

37 CFR 255.3 - Adjustment of royalty rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... fraction thereof, whichever amount is larger, subject to further adjustment pursuant to paragraphs (b....85 cent per minute of playing time or fraction thereof, whichever amount is larger, subject to... embodied in the phonorecord shall be either 5.0 cents, or 0.95 cent per minute of playing time or fraction...

Nutritional status of men attending a soup kitchen: a pilot study.

PubMed Central

Laven, G T; Brown, K C

1985-01-01

Nutritional status and socioeconomic characteristics of 49 men attending a soup kitchen in a residential neighborhood of Birmingham, Alabama were determined by interview, anthropometry and laboratory assays. Laboratory or anthropometric evidence of nutrient deficiency was present in 94 per cent of the subjects. Deficiency of ascorbate (63 per cent), folate (35 per cent), and thiamin (29 per cent) was higher in these men than in either patients or presumably healthy adults. Since soup kitchen meals provided insufficient vitamin C and folate, additional sources of these nutrients should be provided. PMID:4040716

Second consultant opinion for elective orthopedic surgery.

PubMed Central

McCarthy, E G; Finkel, M L

1981-01-01

We abstracted records of 369 patients whose recommendations for elective orthopedic surgery were not confirmed by a second opinion consultant. Six months or more after the initial recommendation for surgery, 82 per cent had not had the operation performed, irrespective of the diagnosis and the characteristics of the physician recommending surgery. Reasons for consultant non-confirmation included: use of a cast, brace, or corrective footwear preferable (26.3 per cent), symptoms not severe enough (18.4 per cent), and physical therapy/exercises preferable (17.8 per cent). PMID:7294266

Diagnosis and initial management of urological injuries associated with 200 consecutive pelvic fractures.

PubMed

Palmer, J K; Benson, G S; Corriere, J N

1983-10-01

During 26 months 200 consecutive patients with fracture of the bony pelvis were evaluated and treated for urological injury. There was no correlation between the extent of pelvic injury and degree of hematuria but hematuria was present in all patients with a urological injury. All urological injuries occurred with anterior arch fractures. The over-all incidence of injury was 13.5 per cent (bladder 9 per cent, urethra 3.5 per cent and combined 1 per cent). Limited extraperitoneal bladder ruptures were treated successfully by Foley catheter drainage.

Veterinarians' role for pet owners facing pet loss

PubMed Central

Fernandez-Mehler, P.; Gloor, P.; Sager, E.; Lewis, F. I.; Glaus, T. M

2013-01-01

Owners' satisfaction with, and expectations from, their veterinarians around euthanasia, including questions on disposal of pet remains subject to animal species, clients' gender, age, family conditions, area of living and type of veterinary clinic visited were evaluated by questionnaire. Questionnaires were to be filled out by clients consecutively visiting the individual practices and hospitals for any kind of consultations. Of 2350 questionnaires distributed, 2008 were returned and available for analysis. Owner satisfaction concerning the procedure of euthanasia was high (92 per cent, 1173/1272). After the event of euthanasia, 14 per cent (170/1250) had changed their veterinarian, even though 75 per cent of these 170 had been satisfied with the procedure. Most owners (88 per cent) expected veterinarians to talk about their pet's final destination, and 38 per cent expected this to happen early in the pet's life. For 81 per cent clients, the veterinarian was the primary informant about the possibilities concerning the disposal of pet remains, and 33 per cent indicated their veterinarian as the contact person to talk about pet loss. Area of living, or veterinary specialisation, only marginally influenced the answers. Veterinarians play an important role to inform their clients concerning questions around euthanasia and the care of pet remains, and to support them during the process of mourning. PMID:23492929

GERIATRIC PATIENTS IN A MENTAL HOSPITAL

PubMed Central

Ernst, Franklin H.; Oliver, W. A.; Simon, Alexander; Malamud, Nathan

1956-01-01

An intensive study was made of men 55 years of age and over admitted to Napa State Hospital with either senile or arteriosclerotic brain disease. A ward treatment program, combining both the medical and psychiatric approaches, was applied to one-half of such patients admitted to a state hospital, with the aim of determining what, if any, effect this program would have on the course of the illnesses. Special laboratory studies showed: (a) Serial electroencephalograms and hospital adjustment ratings appeared to be positively correlated with the patients' clinical course; (b) In 35 per cent of cases the electrocardiographic tracings at the time of admittance were within normal limits; (c) A “pathological level” of blood bromides was found in only one of 340 consecutive admissions in this age group. Sociopsychiatric study of 100 consecutively admitted patients revealed that: (a) 35 per cent of the patients were from the middle, and 65 per cent from the lower classes of society; (b) Only 59 per cent were admitted because of activities specifically psychotic. (c) 63 per cent needed admittance to this state hospital for observation and diagnosis, but only 44 per cent needed to stay for care and treatment; (d) In 88 per cent, specific emotional stresses were present just preceding and coincident with the clinical appearance of the organic brain syndrome. PMID:13304672

Prenatal diagnosis of beta-thalassaemia: experience in a developing country.

PubMed

Saxena, R; Jain, P K; Thomas, E; Verma, I C

1998-01-01

We present our experience with the amplification refractory mutation system (ARMS) for the prenatal diagnosis of beta-thalassaemia in 415 pregnancies of 360 women. Five mutations of the beta-thalassaemia gene common in Asian Indians accounted for 89.2 per cent and rare mutations for 7.2 per cent of all mutant chromosomes, while 3.3 per cent of chromosomes remained uncharacterized. Identical mutations were present in both parents in 43.2 per cent of cases, due to caste-based marriages in India. A confirmed diagnosis was given in 401 (98.3 per cent) cases, of which a complete diagnosis (whether the fetus was normal, a carrier, or homozygous) was possible in 391 (94.2 per cent) of the cases. In 15 couples, the mutation was identified in only one parent. In nine of these, the identified mutation was not present in the fetus, predicting normal/carrier status, while in five the identified mutation was present in the fetus, suggesting carrier/affected status. The abortion rate was 3.9 per cent. Pitfalls in diagnosis were failure of oligonucleotides to work, maternal contamination, and false paternity. The ARMS provides an inexpensive, robust and non-isotopic method for the prenatal diagnosis of beta-thalassaemia in India. Recommendations are outlined for establishing a prenatal diagnostic service in developing countries.

A study on existing knowledge about AIDS among undergraduates of a Nigerian University.

PubMed

Gugnani, A; Ukeje, M A

1993-06-01

This study, carried out during August-October, 1991, involved 236 respondents to a questionnaire designed to determine awareness and attitudes to AIDS and the consequent effect of such awareness on their sexual behaviour. Almost all the medical students were aware of the existence of the disease, while a few (3.8 per cent) of the non-medicos believed that it had not yet reached Nigeria. Most students i.e. 98 per cent and 97 per cent of these respective groups were aware of carrier state of the disease. Only a small percentage of students, mostly medics knew about the exact signs and symptoms of clinical AIDS. The level of knowledge about the modes of transmission of AIDS was found to be adequate. With regard to the effect of this awareness on their behaviour, it was known that a good number of medics (30.37) per cent and non-medics (28.88) per cent had started using condoms. About 40 per cent medicos, and 45 per cent non-medicos revealed an aversion to sit near a person with AIDS thus emphasizing the stigma associated with the disease. Regarding control of AIDS, many felt there should be strict isolation of HIV positive individuals along with a ban on prostitution and homosexuality.

Canine dilated cardiomyopathy: a retrospective study of signalment, presentation and clinical findings in 369 cases.

PubMed

Martin, M W S; Stafford Johnson, M J; Celona, B

2009-01-01

To review the clinical and diagnostic findings and survival of dilated cardiomyopathy from a large population of dogs in England. A retrospective study of the case records of dogs with dilated cardiomyopathy collected between January 1993 and May 2006. There were 369 dogs with dilated cardiomyopathy of which all were pure-bred dogs except for four. The most commonly affected breeds were dobermanns and boxers. Over 95 per cent of dogs weighed more than 15 kg and 73 per cent were male. The median duration of signs before referral was three weeks with 65 per cent presenting in stage 3 heart failure. The most common signs were breathlessness (67 per cent) and coughing (64 per cent). The majority of dogs (89 per cent) had an arrhythmia at presentation and 74 per cent of dogs had radiographic signs of pulmonary oedema or pleural effusion. The median survival time was 19 weeks. Dilated cardiomyopathy occurs primarily in medium to large breed pure-bred dogs, and males are more frequently affected than females. The duration of clinical signs before referral is often short and the survival times are poor. Greater awareness of affected breeds, clinical signs and diagnostic findings may help in early recognition of this disease which often has a short clinical phase.

Water cycle changes over the Mediterranean: a comparison study of a super-high-resolution global model with CMIP3.

PubMed

Jin, Fengjun; Kitoh, Akio; Alpert, Pinhas

2010-11-28

Water cycle components over the Mediterranean for both a current run (1979-2007) and a future run (2075-2099) are studied with the Japan Meteorological Agency's 20 km grid global climate model. Results are compared with another study using the Coupled Model Intercomparison Project Phase 3 ensemble model (hereafter, the Mariotti model). Our results are surprisingly close to Mariotti's. The projected mean annual change rates of precipitation (P) between the future and the current run for sea and land are -11 per cent and -10 per cent, respectively, which are not as high as Mariotti's. Projected changes for evaporation (E) are +9.3 per cent and -3.6 per cent, compared with +7.2 per cent and -8.1 per cent in Mariotti's study, respectively. However, no significant difference in the change in P-E over the sea body was found between these two studies. The increased E over the eastern Mediterranean was found to be higher than that in the western Mediterranean, but the P decrease was lower. The net moisture budget, P-E, shows that the eastern Mediterranean will become even drier than the western Mediterranean. The river model suggests decreasing water inflow to the Mediterranean of approximately 36 per cent (excluding the Nile).

Blunt traumatic bladder rupture: a 10-year perspective.

PubMed

Matlock, Kinzie A; Tyroch, Alan H; Kronfol, Ziad N; McLean, Susan F; Pirela-Cruz, Miguel A

2013-06-01

The purpose of this study was to determine the incidence, features, and associated injuries of intraperitoneal (IP) and extraperitoneal (EP) bladder rupture (BR) resulting from blunt trauma. A retrospective study from September 2001 to August 2011 was performed for blunt traumatic BR in adults. Demographics, mean Injury Severity Score (ISS), mean length of stay (LOS), incidence, mortality, operative repair, and associated injuries were evaluated. Of 15,168 adult blunt trauma admissions over 10 years, 54 patients had BR (EP = 22, IP = 27, EP + IP = 5; incidence = 0.36%). Sixty-three per cent were male. The mean age, ISS, and LOS were 40 years, 29, and 15 days, respectively. The mortality rate was 11 per cent. Fifty-two per cent of BR was the result of a motor vehicle crash. Most BRs were diagnosed by computed tomography cystogram. Eighty per cent had pelvic fracture. Hollow viscus injury was present in 34.5 per cent of patients. Colonic injury was seen in 24 per cent and 9.3 per cent had a rectal injury. Although BR is rare in adult blunt trauma, it is associated with high ISS, LOS, and mortality. Pelvic fractures are essentially present in all patients with EP BR. Hollow viscus injuries, especially colonic and rectal injuries, are more prominent in IP BR.

Theoretical Model for Volume Fraction of UC, 235U Enrichment, and Effective Density of Final U 10Mo Alloy

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

Devaraj, Arun; Prabhakaran, Ramprashad; Joshi, Vineet V.

2016-04-12

The purpose of this document is to provide a theoretical framework for (1) estimating uranium carbide (UC) volume fraction in a final alloy of uranium with 10 weight percent molybdenum (U-10Mo) as a function of final alloy carbon concentration, and (2) estimating effective 235U enrichment in the U-10Mo matrix after accounting for loss of 235U in forming UC. This report will also serve as a theoretical baseline for effective density of as-cast low-enriched U-10Mo alloy. Therefore, this report will serve as the baseline for quality control of final alloy carbon content

A novel approach to gravitation from fluid theory: Titius-Bode structures, flat rotation rate of galaxies, and other predictions

NASA Astrophysics Data System (ADS)

Munera, Hector A.

Following the discovery of quantum phenomena at laboratory scale (Couder & Fort 2006), de Broglie pilot wave theory (De Broglie 1962) has been revived under a hydrodynamic guise (Bush 2015). Theoretically, it boils down to solving the transport equations for the energy and linear momentum densities of a postulated fundamental fluid in terms of classical wave equations, which inherently are Lorentz-invariant and scale-invariant. Instead of the conventional harmonic solutions, for astronomical and gravitational problems the novel solutions for the homogeneous wave equation in spherical coordinates are more suitable (Munera et al. 1995, Munera & Guzman 1997, and Munera 2000). Two groups of solutions are particularly relevant: (a) The inherently-quantized helicoidal solutions that may be applicable to describe spiral galaxies, and (b) The non-harmonic solutions with time (t) and distance (r) entangled in the single variable q = Ct/r (C is the two-way local electromagnetic speed). When these functions are plotted against 1/q they manifestly depict quantum effects in the near field, and Newtonian-like gravity in the far-field. The near-field predicts quantized effects similar to ring structures and to Titius-Bode structures, both in our own solar system and in exoplanets, the correlation between predicted and observed structures being typically larger than 99 per cent. In the far-field, some non-harmonic functions have a rate of decrement with distance slower than inverse-square thus explaining the flat rotation rate of galaxies. Additional implications for Trojan orbits, and quantized effects in photon deflection were also noted.

Formation of stellar clusters in magnetized, filamentary infrared dark clouds

NASA Astrophysics Data System (ADS)

Li, Pak Shing; Klein, Richard I.; McKee, Christopher F.

2018-01-01

Star formation in a filamentary infrared dark cloud (IRDC) is simulated over the dynamic range of 4.2 pc to 28 au for a period of 3.5 × 105 yr, including magnetic fields and both radiative and outflow feedback from the protostars. At the end of the simulation, the star formation efficiency is 4.3 per cent and the star formation rate per free-fall time is εff ≃ 0.04, within the range of observed values. The total stellar mass increases as ∼t2, whereas the number of protostars increases as ∼t1.5. We find that the density profile around most of the simulated protostars is ∼ρ ∝ r-1.5. At the end of the simulation, the protostellar mass function approaches the Chabrier stellar initial mass function. We infer that the time to form a star of median mass 0.2 M⊙ is about 1.4 × 105 yr from the median mass accretion rate. We find good agreement among the protostellar luminosities observed in the large sample of Dunham et al., our simulation and a theoretical estimate, and we conclude that the classical protostellar luminosity problem is resolved. The multiplicity of the stellar systems in the simulation agrees, to within a factor of 2, with observations of Class I young stellar objects; most of the simulated multiple systems are unbound. Bipolar protostellar outflows are launched using a subgrid model, and extend up to 1 pc from their host star. The mass-velocity relation of the simulated outflows is consistent with both observation and theory.

Star formation rates and efficiencies in the Galactic Centre

NASA Astrophysics Data System (ADS)

Barnes, A. T.; Longmore, S. N.; Battersby, C.; Bally, J.; Kruijssen, J. M. D.; Henshaw, J. D.; Walker, D. L.

2017-08-01

The inner few hundred parsecs of the Milky Way harbours gas densities, pressures, velocity dispersions, an interstellar radiation field and a cosmic ray ionization rate orders of magnitude higher than the disc; akin to the environment found in star-forming galaxies at high redshift. Previous studies have shown that this region is forming stars at a rate per unit mass of dense gas which is at least an order of magnitude lower than in the disc, potentially violating theoretical predictions. We show that all observational star formation rate diagnostics - both direct counting of young stellar objects and integrated light measurements - are in agreement within a factor two, hence the low star formation rate (SFR) is not the result of the systematic uncertainties that affect any one method. As these methods trace the star formation over different time-scales, from 0.1 to 5 Myr, we conclude that the SFR has been constant to within a factor of a few within this time period. We investigate the progression of star formation within gravitationally bound clouds on ˜parsec scales and find 1-4 per cent of the cloud masses are converted into stars per free-fall time, consistent with a subset of the considered 'volumetric' star formation models. However, discriminating between these models is obstructed by the current uncertainties on the input observables and, most importantly and urgently, by their dependence on ill-constrained free parameters. The lack of empirical constraints on these parameters therefore represents a key challenge in the further verification or falsification of current star formation theories.

Density scaling on n  =  1 error field penetration in ohmically heated discharges in EAST

NASA Astrophysics Data System (ADS)

Wang, Hui-Hui; Sun, You-Wen; Shi, Tong-Hui; Zang, Qing; Liu, Yue-Qiang; Yang, Xu; Gu, Shuai; He, Kai-Yang; Gu, Xiang; Qian, Jin-Ping; Shen, Biao; Luo, Zheng-Ping; Chu, Nan; Jia, Man-Ni; Sheng, Zhi-Cai; Liu, Hai-Qing; Gong, Xian-Zu; Wan, Bao-Nian; Contributors, EAST

2018-05-01

Density scaling of error field penetration in EAST is investigated with different n  =  1 magnetic perturbation coil configurations in ohmically heated discharges. The density scalings of error field penetration thresholds under two magnetic perturbation spectra are br\\propto n_e0.5 and br\\propto n_e0.6 , where b r is the error field and n e is the line averaged electron density. One difficulty in understanding the density scaling is that key parameters other than density in determining the field penetration process may also be changed when the plasma density changes. Therefore, they should be determined from experiments. The estimated theoretical analysis (br\\propto n_e0.54 in lower density region and br\\propto n_e0.40 in higher density region), using the density dependence of viscosity diffusion time, electron temperature and mode frequency measured from the experiments, is consistent with the observed scaling. One of the key points to reproduce the observed scaling in EAST is that the viscosity diffusion time estimated from energy confinement time is almost constant. It means that the plasma confinement lies in saturation ohmic confinement regime rather than the linear Neo-Alcator regime causing weak density dependence in the previous theoretical studies.

Prevalence of risk factors for non-communicable diseases in rural & urban Tamil Nadu

PubMed Central

Oommen, Anu Mary; Abraham, Vinod Joseph; George, Kuryan; Jose, V. Jacob

2016-01-01

Background & objectives: Surveillance of risk factors is important to plan suitable control measures for non-communicable diseases (NCDs). The objective of this study was to assess the behavioural, physical and biochemical risk factors for NCDs in Vellore Corporation and Kaniyambadi, a rural block in Vellore district, Tamil Nadu, India. Methods: This cross-sectional study was carried out among 6196 adults aged 30-64 yr, with 3799 participants from rural and 2397 from urban areas. The World Health Organization-STEPS method was used to record behavioural risk factors, anthropometry, blood pressure, fasting blood glucose and lipid profile. Multiple logistic regression was used to assess associations between risk factors. Results: The proportion of tobacco users (current smoking or daily use of smokeless tobacco) was 23 per cent in the rural sample and 18 per cent in the urban, with rates of smoking being similar. Ever consumption of alcohol was 62 per cent among rural men and 42 per cent among urban men. Low physical activity was seen among 63 per cent of the urban and 43 per cent of the rural sample. Consumption of fruits and vegetables was equally poor in both. In the urban sample, 54 per cent were overweight, 29 per cent had hypertension and 24 per cent diabetes as compared to 31, 17 and 11 per cent, respectively, in the rural sample. Physical inactivity was associated with hypertension, body mass index (BMI) ≥25 kg/m2, central obesity and dyslipidaemia after adjusting for other factors. Increasing age, male sex, BMI ≥25 kg/m2 and central obesity were independently associated with both hypertension and diabetes. Interpretation & conclusions: Diabetes, hypertension, dyslipidaemia, physical inactivity and overweight were higher in the urban area as compared to the rural area which had higher rates of smokeless tobacco use and alcohol consumption. Smoking and inadequate consumption of fruits and vegetables were equally prevalent in both the urban and rural samples. There is an urgent need to address behavioural risk factors such as smoking, alcohol consumption, physical inactivity and inadequate intake of fruits and vegetables through primary prevention. PMID:28139545

The prevalence and causes of visual impairment in seven-year-old children.

PubMed

Ghaderi, Soraya; Hashemi, Hassan; Jafarzadehpur, Ebrahim; Yekta, Abbasali; Ostadimoghaddam, Hadi; Mirzajani, Ali; Khabazkhoob, Mehdi

2018-05-01

To report the prevalence and causes of visual impairment in seven-year-old children in Iran and its relationship with socio-economic conditions. In a cross-sectional population-based study, first-grade students in the primary schools of eight cities in the country were randomly selected from different geographic locations using multistage cluster sampling. The examinations included visual acuity measurement, ocular motility evaluation, and cycloplegic and non-cycloplegic refraction. Using the definitions of the World Health Organization (presenting visual acuity less than or equal to 6/18 in the better eye) to estimate the prevalence of vision impairment, the present study reported presenting visual impairment in seven-year-old children. Of 4,614 selected students, 4,106 students participated in the study (response rate 89 per cent), of whom 2,127 (51.8 per cent) were male. The prevalence of visual impairment according to a visual acuity of 6/18 was 0.341 per cent (95 per cent confidence interval 0.187-0.571); 1.34 per cent (95 per cent confidence interval 1.011-1.74) of children had visual impairment according to a visual acuity of 6/18 in at least one eye. Sixty-six (1.6 per cent) and 23 (0.24 per cent) children had visual impairment according to a visual acuity of 6/12 in the worse and better eye, respectively. The most common causes of visual impairment were refractive errors (81.8 per cent) and amblyopia (14.5 per cent). Among different types of refractive errors, astigmatism was the main refractive error leading to visual impairment. According to the concentration index, the distribution of visual impairment in children from low-income families was higher. This study revealed a high prevalence of visual impairment in a representative sample of seven-year-old Iranian children. Astigmatism and amblyopia were the most common causes of visual impairment. The distribution of visual impairment was higher in children from low-income families. Cost-effective strategies are needed to address these easily treatable causes of visual impairment. © 2017 Optometry Australia.

Pre-AIDS mortality in the Edinburgh City Hospital HIV cohort.

PubMed

Seaman, S R; Brettle, R P; Gore, S M

1997-11-15

In this paper, we look at the incidence and predictive factors of pre-AIDS mortality among HIV-infected individuals, and injecting drug users (IDUs) in particular, and compare IDUs with non-IDUs. 627 patients (73 per cent IDUs) of the Edinburgh City Hospital HIV Cohort were enrolled pre-AIDS and followed up until September 1994. Analyses were performed using cumulative hazard and cumulative incidence estimators for a competing risks model, the Cox proportional hazards model and the non-parametric hazard estimator of Fusaro et al. (1993). The effects of age and CD4 T-lymphocyte cell count, progressively depleted during HIV progression, were investigated. 60 deaths occurred in AIDS-free patients during follow-up; 25 were drug-related deaths in IDUs. Pre-AIDS mortality was higher among IDUs than non-IDUs (p = 0.07). The cumulative incidences of pre-AIDS death after five years from enrollment were 11 per cent in IDUs and 6 per cent in non-IDUs; the cumulative AIDS incidences were, respectively, 19 per cent and 32 per cent. After eight years, cumulative pre-AIDS death incidence was 15 per cent among IDUs; cumulative AIDS incidence among IDUs was 35 per cent. Both groups had similar risks of medically-related (non-AIDS)-MRNA-death. Age and CD4 count were both individually predictive of MRNA death (relative risks (RRs); 2.1 per decade of life, p < 0.01; and 1.9 for each 100 cells per 100 microliters lost, p < 0.0001), although when used together age was less significant (RR 1.6, p = 0.07). Neither was statistically significant for drug-related mortality, although hazard may be lower in older individuals and may increase with falling CD4 count. The drug-related mortality was 1.1 per cent: 2.3 per cent in the first two years after enrollment, and 0.4 per cent thereafter. We conclude that older HIV-infected individuals are at greater risk of medically-related death before AIDS. This risk increases as CD4 count declines. Drug-related hazard may be greater in younger individuals and may increase as CD4 counts fall, but neither effect was formally significant.

Serological diagnosis of bovine neosporosis: a Bayesian evaluation of two antibody ELISA tests for in vivo diagnosis in purchased and abortion cattle.

PubMed

Roelandt, S; Van der Stede, Y; Czaplicki, G; Van Loo, H; Van Driessche, E; Dewulf, J; Hooyberghs, J; Faes, C

2015-06-06

Currently, there are no perfect reference tests for the in vivo detection of Neospora caninum infection. Two commercial N caninum ELISA tests are currently used in Belgium for bovine sera (TEST A and TEST B). The goal of this study is to evaluate these tests used at their current cut-offs, with a no gold standard approach, for the test purpose of (1) demonstration of freedom of infection at purchase and (2) diagnosis in aborting cattle. Sera of two study populations, Abortion population (n=196) and Purchase population (n=514), were selected and tested with both ELISA's. Test results were entered in a Bayesian model with informative priors on population prevalences only (Scenario 1). As sensitivity analysis, two more models were used: one with informative priors on test diagnostic accuracy (Scenario 2) and one with all priors uninformative (Scenario 3). The accuracy parameters were estimated from the first model: diagnostic sensitivity (Test A: 93.54 per cent-Test B: 86.99 per cent) and specificity (Test A: 90.22 per cent-Test B: 90.15 per cent) were high and comparable (Bayesian P values >0.05). Based on predictive values in the two study populations, both tests were fit for purpose, despite an expected false negative fraction of ±0.5 per cent in the Purchase population and ±5 per cent in the Abortion population. In addition, a false positive fraction of ±3 per cent in the overall Purchase population and ±4 per cent in the overall Abortion population was found. British Veterinary Association.

Survey of UK horse owners' knowledge of equine arboviruses and disease vectors.

PubMed

Chapman, Gail Elaine; Baylis, Matthew; Archer, Debra C

2018-05-15

Increased globalisation and climate change have led to concern about the increasing risk of arthropod-borne virus (arbovirus) outbreaks globally. An outbreak of equine arboviral disease in northern Europe could impact significantly on equine welfare, and result in economic losses. Early identification of arboviral disease by horse owners may help limit disease spread. In order to determine what horse owners understand about arboviral diseases of horses and their vectors, the authors undertook an open, cross-sectional online survey of UK horse owners. The questionnaire was distributed using social media and a press release and was active between May and July 2016. There were 466 respondents, of whom 327 completed the survey in full. High proportions of respondents correctly identified photographic images of biting midges (71.2 per cent) and mosquitoes (65.4 per cent), yet few were aware that they transmit equine infectious diseases (31.4 per cent and 35.9 per cent, respectively). Of the total number of respondents, only 7.4 per cent and 16.2 per cent correctly named a disease transmitted by biting midges and mosquitoes, respectively. Only 13.1 per cent and 12.5 per cent of participants identified specific clinical signs of African horse sickness (AHS) and West Nile virus (WNV), respectively. This study demonstrates that in the event of heightened disease risk educational campaigns directed towards horse owners need to be implemented, focussing on disease awareness, clinical signs and effective disease prevention strategies. © British Veterinary Association (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Night emergency cover for ENT in England: a national survey.

PubMed

Biswas, D; Rafferty, A; Jassar, P

2009-08-01

To evaluate the quality of out-of-hours ENT on-call cover by junior doctors, in view of the European Working Time Directive and the recent changes in the National Health Service workforce due to the 'Modernising Medical Careers' initiative, in England. We performed a national survey of first-on-call doctors for ENT, using a telephone questionnaire. Hospital contact details were sourced from the National Health Service website. The inclusion criterion was hospitals providing acute ENT facilities overnight in England. One hundred and nineteen hospitals were contacted; 91 were eligible, and 83 interviews were conducted. The grade of the first-on-call ENT doctor ranged from foundation year two (19 per cent) to registrar level or above (13 per cent). Forty-nine respondents (68 per cent) reported having no previous ENT experience. Fifty-three respondents (74 per cent) covered more than one speciality at night, with seven (10 per cent) covering four or more specialities. The second-on-call doctor was non-resident in 63 cases (88 per cent). Thirty respondents (42 per cent) stated that they did not feel comfortable managing common ENT emergencies as the first doctor on call. Otorhinolaryngology induction courses were offered in 37 of the respondents' hospitals (51 per cent), these courses were of varying duration. Night-time ENT care is often provided by junior doctors with little experience of the speciality, who are often also responsible for covering multiple specialities. Many reported not feeling comfortable managing common ENT emergencies. Structured induction programmes would help to provide basic knowledge and should be mandatory for all doctors covering ENT.

Quantitative analysis of antibiotic usage in British sheep flocks.

PubMed

Davies, Peers; Remnant, John G; Green, Martin J; Gascoigne, Emily; Gibbon, Nick; Hyde, Robert; Porteous, Jack R; Schubert, Kiera; Lovatt, Fiona; Corbishley, Alexander

2017-11-11

The aim of this study was to examine the variation in antibiotic usage between 207 commercial sheep flocks using their veterinary practice prescribing records. Mean and median prescribed mass per population corrected unit (mg/PCU) was 11.38 and 5.95, respectively and closely correlated with animal defined daily dose (ADDD) 1.47 (mean), 0.74 (median) (R 2 =0.84, P<0.001). This is low in comparison with the suggested target (an average across all the UK livestock sectors) of 50 mg/PCU. In total, 80 per cent of all antibiotic usage occurred in the 39 per cent of flocks where per animal usage was greater than 9.0 mg/PCU. Parenteral antibiotics, principally oxytetracycline, represented 82 per cent of the total prescribed mass, 65.5 per cent of antibiotics (mg/PCU) were prescribed for the treatment of lameness. Oral antibiotics were prescribed to 49 per cent of flocks, 64 per cent of predicted lamb crop/farm. Lowland flocks were prescribed significantly more antibiotics than hill flocks. Variance partitioning apportioned 79 per cent of variation in total antibiotic usage (mg/PCU) to the farm level and 21 per cent to the veterinary practice indicating that veterinary practices have a substantial impact on overall antimicrobial usage. Reducing antibiotic usage in the sheep sector should be possible with better understanding of the drivers of high usage in individual flocks and of veterinary prescribing practices. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

26 CFR 49.4263-2 - Charges not exceeding 60 cents.

Code of Federal Regulations, 2012 CFR

2012-04-01

... not exceeding 60 cents. (a) In general. The tax imposed by section 4261 does not apply to... round trip does not exceed 60 cents. (c) Charters. An amount paid for the charter of a car, train, motor...) Seating or sleeping accommodations. Any amount paid for seating or sleeping accommodations is not subject...

26 CFR 49.4263-2 - Charges not exceeding 60 cents.

Code of Federal Regulations, 2011 CFR

2011-04-01

... not exceeding 60 cents. (a) In general. The tax imposed by section 4261 does not apply to... round trip does not exceed 60 cents. (c) Charters. An amount paid for the charter of a car, train, motor...) Seating or sleeping accommodations. Any amount paid for seating or sleeping accommodations is not subject...

26 CFR 49.4263-2 - Charges not exceeding 60 cents.

Code of Federal Regulations, 2013 CFR

2013-04-01

... not exceeding 60 cents. (a) In general. The tax imposed by section 4261 does not apply to... round trip does not exceed 60 cents. (c) Charters. An amount paid for the charter of a car, train, motor...) Seating or sleeping accommodations. Any amount paid for seating or sleeping accommodations is not subject...

26 CFR 49.4263-2 - Charges not exceeding 60 cents.

Code of Federal Regulations, 2010 CFR

2010-04-01

... not exceeding 60 cents. (a) In general. The tax imposed by section 4261 does not apply to... round trip does not exceed 60 cents. (c) Charters. An amount paid for the charter of a car, train, motor...) Seating or sleeping accommodations. Any amount paid for seating or sleeping accommodations is not subject...

Groin dressing after cardiac catheterization. Comparison between light dressing with thin transparent tape (Tegaderm) and conventional tight/pressure dressing with an elastic adhesive bandage (Tensoplast).

PubMed

Boonbaichaiyapruck, S; Hutayanon, P; Chanthanamatta, P; Dumrongwatana, T; Intarayotha, N; Krisdee, V; Yamvong, S

2001-12-01

Post cardiac catheterization puncture site care is usually done with a tight pressure dressing by an elastic adhesive bandage (Tensoplast) due to the belief that it should prevent bleeding. The practice is uncomfortable to the patients. The authors compared a new way of dressing using light transparent tape (Tegaderm) to the conventional tight pressure one. 126 post coronary angiography patients were randomized to have their groins dressed either with Tensoplast or with Tegaderm. Patients ambulated 8 hours after the procedures. The groin was evaluated for pain, discomfort and bleeding complications. 49 per cent in the Tensoplast vs 26.9 per cent in the Tegaderm group experienced pain (p value of 0.01). 55.5 per cent in the Tensoplast group vs 11.1 per cent in the Tegaderm group reported discomfort. 4.7 per cent in the Tensoplast vs 1.6 per cent in the Tegaderm group developed bleeding or hematoma. Dressing of the puncture site after cardiac catheterization with Tegaderm was more comfortable than the conventional Tensoplast without any difference in bleeding complications.

THE RELATIVE EFFECTS OF PROTEIN, CHOLINE, AND METHIONINE IN THE TREATMENT OF EXPERIMENTAL DIETARY CIRRHOSIS IN THE RAT

PubMed Central

Plough, Irvin C.; Patek, Arthur J.; Bevans, Margaret

1952-01-01

Cirrhosis of the liver was produced in rats by feeding a diet low in protein (4 per cent casein) and deficient in lipotropic factors. The degree of liver cirrhosis was determined from specimens obtained at biopsy. Comparable groups of animals then were treated with diets containing 4 per cent casein and 30 per cent casein. The 4 per cent casein diets were supplemented with choline and methionine; the 30 per cent casein diets were fed with and without added choline. On supplementing the low protein diet with choline and methionine the animals remained feeble, their growth remained stunted, and their livers showed signs of progressive cirrhosis. In contrast, animals fed the higher protein diet (with or without added choline) grew normally, and their livers showed signs indicating arrest and regression of the disease process. These studies suggest that the feeding of high protein (30 per cent casein) diets to rats with nutritional cirrhosis produces reparative effects greater than those attributable to the supplements choline and methionine. PMID:14955576

Prevalence of allergic rhinitis among elementary and middle school students in Changsha city and its impact on quality of life.

PubMed

Song, Y; Wang, M; Xie, J; Li, W; Zhang, X; Wang, T; Tan, G

2015-11-01

To investigate the prevalence of allergic rhinitis among elementary and middle school students and examine its impact on their quality of life. Stratified sampling and cluster sampling surveys were performed among 10-17-year-old students in Changsha city from June 2011 to April 2012. In the stratified sampling survey, the self-reported allergic rhinitis rate was 42.5 per cent. Further examination demonstrated that the average prevalence of allergic rhinitis was 19.4 per cent. The cluster sampling survey demonstrated that 214 of 814 students appeared to be atopic (26.3 per cent). The prevalence of allergic rhinitis and asthma was 17.2 and 2.1 per cent, respectively. In total, 71 atopic individuals (8.7 per cent) were without any symptoms of allergic disease. Further analysis showed that allergic rhinitis influenced the students' sleep, emotions and memory (p < 0.001). The prevalence of allergic rhinitis was 15.8 -19.4 per cent, showing an increase with age. Allergic rhinitis affected students' sleep, emotions and memory.

Bacterial strain changes during chronic otitis media surgery.

PubMed

Kim, G J; Yoo, S; Han, S; Bu, J; Hong, Y; Kim, D-K

2017-09-01

Cultures obtained from pre-operative middle-ear swabs from patients with chronic otitis media have traditionally been used to guide antibiotic selection. This study investigated changes in the bacterial strains of the middle ear during chronic otitis media surgery. Pre-operative bacterial cultures of otorrhoea, and peri-operative cultures of the granulation tissue in either the middle ear or mastoid cavity, were obtained. Post-operative cultures were selectively obtained when otorrhoea developed after surgery. Bacterial growth was observed in 45.5 per cent of pre-operative cultures, 13.5 per cent of peri-operative cultures and 4.5 per cent of post-operative cultures. Methicillin-resistant Staphylococcus aureus was identified as the most common bacteria in all pre-operative (32.4 per cent), peri-operative (52.4 per cent) and post-operative (71.4 per cent) tests, and the percentage of Methicillin-resistant S aureus increased from the pre- to the post-operative period. The bacterial culture results for post-operative otorrhoea showed low agreement with those for pre-operative or peri-operative culture, and strain re-identification was required.

Presence of the glycogen synthase 1 (GYS1) mutation causing type 1 polysaccharide storage myopathy in continental European draught horse breeds.

PubMed

Baird, J D; Valberg, S J; Anderson, S M; McCue, M E; Mickelson, J R

2010-11-13

The purpose of this study was to determine which continental European draught horse breeds harbour a mutation in the glycogen synthase 1 gene (GYS1) that is known to be responsible for type 1 polysaccharide storage myopathy in quarter horses and North American draught horses. Of a non-random selection of continental European draught horses belonging to 13 breeds, 62 per cent (250 of 403) tested were found to carry the mutant allele. The horses were located in Belgium, France, Germany, The Netherlands, Spain and Sweden. The mutation was identified in animals from each of the breeds examined. In the breeds in which more than 15 animals were available for testing, the highest percentages of GYS1-positive horses were found in the Belgian trekpaard (92 per cent; 35 of 38 horses tested), Comtois (80 per cent; 70 of 88), Netherlands trekpaard (74 per cent; 17 of 23), Rheinisch-Deutsches kaltblut (68 per cent; 30 of 44) and Breton (64 per cent; 32 of 51).

The water, deuterium, gas and uranium content of tektites

USGS Publications Warehouse

Friedman, I.

1958-01-01

The water content, deuterium concentration of the water, total gas and uranium contents were determined on tektite samples and other glass samples from Texas, Australia, Philippine Islands, Java, French Indo-China, Czechoslovakia, Libyan Desert, Billiton Island, Thailand, French West Africa, Peru, and New Mexico. The water content ranges from 0.24 per cent for the Peru tektite, to 0.0002 per cent for a moldavite. The majority of the tektites have less than 0.05 per cent water, and average 0.005 per cent H2O by weight. No other gases were detected, the lower detection limit being about 1 p.p.m. by weight. The deuterium content of the water in tektites is in the same range as that in terrestrial waters, and varies from 0.010 mole per cent to 0.0166 mole per cent deuterium. The uranium content is about from 1 to 3 p.p.m. The possible origin of tektites is discussed. The experimental data presented favour their being originally terrestrial, but produced by some catastrophic event. An extra-terrestrial source is not ruled out. ?? 1958.

A status survey of common water-borne diseases in desert city Bikaner (NW Rajasthan, India).

PubMed

Saxena, M M; Chhabra, Chetna

2004-03-01

Water is scarce and, in general, a low quality resource in desert areas and the Indian desert is no exception. With this in view, the present study was taken up to survey the status of common water-borne diseases epidemiological trends in the desert city Bikaner (NW Rajasthan). In the city, 15.5 per cent population and 44.5 per cent families were found to suffer from one or more common water-borne diseases including amoebiasis, diarrhoea, dysentery, jaundice and typhoid. No case of fluorosis was recorded. The highest incidence was that of diarrhoea (5.4 per cent population). The worst affected and safe zones in the city were identified and the trends of different diseases in different zones of the city are discussed. The highest incidence of diseases was noted during summer (58.8 per cent) followed by winter (34.1 per cent) and monsoon (7.0 per cent). Relationship of diseases with population attributes like age, education, economy and family size are also discussed. Attributes for contamination of drinking water have been tried to identify and safety measures suggested.

Determination of the rate constant for the NH2(X2B1) + NH2(X2B1) recombination reaction with collision partners He, Ne, Ar, and N2 at low pressures and 296 K. Part 1.

PubMed

Altinay, Gokhan; Macdonald, R Glen

2012-02-09

The recombination rate constant for the NH(2)(X(2)B(1)) + NH(2)(X(2)B(1)) → N(2)H(4)(X(1)A(1)) reaction in He, Ne, Ar, and N(2) was measured over the pressure range 1-20 Torr at a temperature of 296 K. The NH(2) radical was produced by 193 nm laser photolysis of NH(3) dilute in the third-body gas. The production of NH(2) and the loss of NH(3) were monitored by high-resolution continuous-wave absorption spectroscopy: NH(2) on the (1)2(21) ← (1)3(31) rotational transition of the (0,7,0)A(2)A(1) ← (0,0,0) X(2)B(1) vibronic band and NH(3) on either inversion doublet of the (q)Q(3)(3) rotational transition of the ν(1) fundamental. Both species were detected simultaneously following the photolysis laser pulse. The broader Doppler width of the NH(2) spectral transition allowed temporal concentration measurements to be extended up to 20 Torr before pressure broadening effects became significant. Fall-off behavior was identified and the bimolecular rate constants for each collision partner were fit to a simple Troe form defined by the parameters, k(0), k(inf), and F(cent). This work is the first part of a two part series in which part 2 will discuss the measurements with more efficient energy transfer collision partners CH(4), C(2)H(6), CO(2), CF(4), and SF(6). The pressure range was too limited to extract any new information on k(inf), and k(inf) was taken from the theoretical calculations of Klippenstein et al. (J. Phys. Chem A 2009, 113, 10241) as k(inf) = 7.9 × 10(-11) cm(3) molecule(-1) s(-1) at 296 K. The individual Troe parameters were: He, k(0) = 2.8 × 10(-29) and F(cent) = 0.47; Ne, k(0) = 2.7 × 10(-29) and F(cent) = 0.34; Ar, k(0) = 4.4 × 10(-29) and F(cent) = 0.41; N(2), k(0) = 5.7 × 10(-29) and F(cent) = 0.61, with units cm(6) molecule(-2) s(-1) for k(0). In the case of N(2) as the third body, it was possible to measure the recombination rate constant for the NH(2) + H reaction near 20 Torr total pressure. The pure three-body recombination rate constant was (2.3 ± 0.55) × 10(-30) cm(6) molecule(-2) s(-1), where the uncertainty is the total experimental uncertainty including systematic errors at the 2σ level of confidence.

Summer foods of American widgeon, mallards, and a green-winged teal near Great Slave Lake, N.W.T

USGS Publications Warehouse

Bartonek, J.C.

1972-01-01

Foods found in three species of dabbling ducks collected during summer from bog ponds, and sedge pools in taiga on the north side of Great Slave Lake, Northwest Territories, are described. Animal material in the esophageal contents of 10 adult American Widgeons (Mareca americana) averaged 31 i?? 34 per cent (P<0.05) by volume. A significantly higher percentage of animal material was found in Class I and II widgeon ducklings (66 i?? 22 per cent) than in Class IIIa ducklings and flying juveniles (12 i?? 20 per cent) of this species. Animal material comprised 87 i?? 35 per cent of esophageal contents from five Class II and flying juvenile Mallards (Anas platyrhynchos) and 100 per cent of that from an adult female Green-winged Teal (A. carolinensis).

In vivo measurement of human body composition

NASA Technical Reports Server (NTRS)

Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Price, D. C.

1974-01-01

The female bed rest study has shown that, the response of women to prolonged recumbency of 2 to 3 weeks duration is very similar to that displayed by men. Some of the key findings in the women after 17 days of continuous recumbency are: (1) a decrease in plasma volume of 12-13 per cent; (2) a small decrease in total body water; (3) a decrease in total body potassium of 3 to 4 per cent; (4) a decrease in plasma potassium concentration of 4 to 5 per cent; (5) a decrease in total circulating plasma protein of 11 to 12 per cent; (6) a decrease in urinary norepinephrine excretion rate of 27 to 28 per cent; (7) a possible increase in urinary magnesium, calcium, and phosphate excretion rates; and (8) a possible increase in urinary citrate excretion rate.

Influence of selective breeding on the prevalence of chorioretinal dysplasia and coloboma in the rough collie in Sweden.

PubMed

Wallin-Håkanson, B; Wallin-Håkanson, N; Hedhammar, A

2000-02-01

A total of 8204 rough collies, representing 76 per cent of all collies registered by the Swedish Kennel Club between 1989 and 1997, were examined before 10 weeks of age for collie eye anomaly (CEA). All dogs were permanently identified and examination results were registered and computerised. The policy of breeders during the study period was to select against coloboma in breeding stock, but to allow breeding of chorioretinal dysplasia (CRD) affected animals. The prevalence of CRD increased significantly from 54.2 per cent to 68.1 per cent (P < 0.001) from 1989 to 1997, while the prevalence of coloboma did not (8.3 per cent to 8.5 per cent, P = 0.4). These results are not compatible with a simple, recessive, autosomal inheritance for the entire CEA complex.

The prospects for solar energy use in industry within the United Kingdom

NASA Astrophysics Data System (ADS)

Lewis, C. W.

1980-01-01

An assessment of the potential for solar energy applications within U.K. industry has been made, using a disaggregated breakdown of energy consumption in the eight industrial sectors by fuel and end-use, and taking account of solar collector performance under U.K. climatic conditions. Solar contributions of 35 per cent of process boiler heat up to a temperature of 80 C and 10 per cent in the 80-120 C range are considered feasible, along with 35 per cent of non-industrial water heating. After employing energy conservation techniques currently more cost-effective than solar systems, an additional 3.5 per cent of U.K. primary energy expended in manufacturing industry (excluding iron and steel production) could be contributed by solar. This represents 1 per cent of the U.K. national primary energy demand.

Ultrastrong steel via minimal lattice misfit and high-density nanoprecipitation

NASA Astrophysics Data System (ADS)

Jiang, Suihe; Wang, Hui; Wu, Yuan; Liu, Xiongjun; Chen, Honghong; Yao, Mengji; Gault, Baptiste; Ponge, Dirk; Raabe, Dierk; Hirata, Akihiko; Chen, Mingwei; Wang, Yandong; Lu, Zhaoping

2017-04-01

Next-generation high-performance structural materials are required for lightweight design strategies and advanced energy applications. Maraging steels, combining a martensite matrix with nanoprecipitates, are a class of high-strength materials with the potential for matching these demands. Their outstanding strength originates from semi-coherent precipitates, which unavoidably exhibit a heterogeneous distribution that creates large coherency strains, which in turn may promote crack initiation under load. Here we report a counterintuitive strategy for the design of ultrastrong steel alloys by high-density nanoprecipitation with minimal lattice misfit. We found that these highly dispersed, fully coherent precipitates (that is, the crystal lattice of the precipitates is almost the same as that of the surrounding matrix), showing very low lattice misfit with the matrix and high anti-phase boundary energy, strengthen alloys without sacrificing ductility. Such low lattice misfit (0.03 ± 0.04 per cent) decreases the nucleation barrier for precipitation, thus enabling and stabilizing nanoprecipitates with an extremely high number density (more than 1024 per cubic metre) and small size (about 2.7 ± 0.2 nanometres). The minimized elastic misfit strain around the particles does not contribute much to the dislocation interaction, which is typically needed for strength increase. Instead, our strengthening mechanism exploits the chemical ordering effect that creates backstresses (the forces opposing deformation) when precipitates are cut by dislocations. We create a class of steels, strengthened by Ni(Al,Fe) precipitates, with a strength of up to 2.2 gigapascals and good ductility (about 8.2 per cent). The chemical composition of the precipitates enables a substantial reduction in cost compared to conventional maraging steels owing to the replacement of the essential but high-cost alloying elements cobalt and titanium with inexpensive and lightweight aluminium. Strengthening of this class of steel alloy is based on minimal lattice misfit to achieve maximal precipitate dispersion and high cutting stress (the stress required for dislocations to cut through coherent precipitates and thus produce plastic deformation), and we envisage that this lattice misfit design concept may be applied to many other metallic alloys.

CO abundance variations in the Orion Molecular Cloud

NASA Astrophysics Data System (ADS)

Ripple, F.; Heyer, M. H.; Gutermuth, R.; Snell, R. L.; Brunt, C. M.

2013-05-01

Infrared stellar photometry from the Two Micron All-Sky Survey (2MASS) and spectral line imaging observations of 12CO and 13CO J = 1-0 line emission from the Five College Radio Astronomy Observatory (FCRAO) 14-m telescope are analysed to assess the variation of the CO abundance with physical conditions throughout the Orion A and Orion B molecular clouds. Three distinct Av regimes are identified in which the ratio between the 13CO column density and visual extinction changes corresponding to the photon-dominated envelope, the strongly self-shielded interior, and the cold, dense volumes of the clouds. Within the strongly self-shielded interior of the Orion A cloud, the 13CO abundance varies by 100 per cent with a peak value located near regions of enhanced star formation activity. The effect of CO depletion on to the ice mantles of dust grains is limited to regions with Av > 10 mag and gas temperatures less than ˜20 K as predicted by chemical models that consider thermal evaporation to desorb molecules from grain surfaces. Values of the molecular mass of each cloud are independently derived from the distributions of Av and 13CO column densities with a constant 13CO-to-H2 abundance over various extinction ranges. Within the strongly self-shielded interior of the cloud (Av> 3 mag), 13CO provides a reliable tracer of H2 mass with the exception of the cold, dense volumes where depletion is important. However, owing to its reduced abundance, 13CO does not trace the H2 mass that resides in the extended cloud envelope, which comprises 40-50 per cent of the molecular mass of each cloud. The implied CO luminosity to mass ratios, M/LCO, are 3.2 and 2.9 for Orion A and Orion B, respectively, which are comparable to the value (2.9), derived from γ-ray observations of the Orion region. Our results emphasize the need to consider local conditions when applying CO observations to derive H2 column densities.

Ultrastrong steel via minimal lattice misfit and high-density nanoprecipitation.

PubMed

Jiang, Suihe; Wang, Hui; Wu, Yuan; Liu, Xiongjun; Chen, Honghong; Yao, Mengji; Gault, Baptiste; Ponge, Dirk; Raabe, Dierk; Hirata, Akihiko; Chen, Mingwei; Wang, Yandong; Lu, Zhaoping

2017-04-27

Next-generation high-performance structural materials are required for lightweight design strategies and advanced energy applications. Maraging steels, combining a martensite matrix with nanoprecipitates, are a class of high-strength materials with the potential for matching these demands. Their outstanding strength originates from semi-coherent precipitates, which unavoidably exhibit a heterogeneous distribution that creates large coherency strains, which in turn may promote crack initiation under load. Here we report a counterintuitive strategy for the design of ultrastrong steel alloys by high-density nanoprecipitation with minimal lattice misfit. We found that these highly dispersed, fully coherent precipitates (that is, the crystal lattice of the precipitates is almost the same as that of the surrounding matrix), showing very low lattice misfit with the matrix and high anti-phase boundary energy, strengthen alloys without sacrificing ductility. Such low lattice misfit (0.03 ± 0.04 per cent) decreases the nucleation barrier for precipitation, thus enabling and stabilizing nanoprecipitates with an extremely high number density (more than 10 24 per cubic metre) and small size (about 2.7 ± 0.2 nanometres). The minimized elastic misfit strain around the particles does not contribute much to the dislocation interaction, which is typically needed for strength increase. Instead, our strengthening mechanism exploits the chemical ordering effect that creates backstresses (the forces opposing deformation) when precipitates are cut by dislocations. We create a class of steels, strengthened by Ni(Al,Fe) precipitates, with a strength of up to 2.2 gigapascals and good ductility (about 8.2 per cent). The chemical composition of the precipitates enables a substantial reduction in cost compared to conventional maraging steels owing to the replacement of the essential but high-cost alloying elements cobalt and titanium with inexpensive and lightweight aluminium. Strengthening of this class of steel alloy is based on minimal lattice misfit to achieve maximal precipitate dispersion and high cutting stress (the stress required for dislocations to cut through coherent precipitates and thus produce plastic deformation), and we envisage that this lattice misfit design concept may be applied to many other metallic alloys.