75 research outputs found

    Comment on "Spatial optical solitons in highly nonlocal media" and related papers

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    In a recent paper [A. Alberucci, C. Jisha, N. Smyth, and G. Assanto, Phys. Rev. A 91, 013841 (2015)], Alberucci et al. have studied the propagation of bright spatial solitary waves in highly nonlocal media. We find that the main results in that and related papers, concerning soliton shape and dynamics, based on the accessible soliton (AS) approximation, are incorrect; the correct results have already been published by others. These and other inconsistencies in the paper follow from the problems in applying the AS approximation in earlier papers by the group that propagated to the later papers. The accessible soliton theory cannot describe accurately the features and dynamics of solitons in highly nonlocal media.Comment: 2 page

    Influence of Blood and Milk Selenium Concentration on Somatic Cell Count in Early and Mid Lactation

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    The aim of this study was to determine the effect of selenium concentration in blood and milk in early lactation on somatic cell count. The average selenium concentration in the blood serum was 0.62 ± 0.11 μmol/l and in the milk serum 0.61 ± 0.07 μmol/l. Optimal blood selenium concentrations were found in 19 cows and suboptimal concentrations in 11 cows. Optimal milk selenium concentration was found in 14 cows and suboptimal in 16 cows. The average milk production per cow was 23.12 ± 3.1 liters / day and the average somatic cell count in the first and sixth months of lactation was 5.34 ± 5 (log transformed) and 5.12 ± 4.9, respectively. Blood selenium concentration correlated negatively with milk somatic cell count in early and mid lactation. The classification of cows based on blood selenium concentration gave results which suggested that selenium-deficient cows had a significantly higher somatic cell count in early lactation (the first month) and mid lactation (the sixth month). Blood selenium is an important predictor of milk somatic cell count. Somatic cell count in milk is not dependent upon selenium concentration in milk or interaction blood×milk selenium. Selenium concentration is not in connection with milk production

    Metabolic acclimation to heat stress in farm housed Holstein cows with different body condition scores

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    The aim of this study was to determine the effects of body condition score to metabolic acclimation in heat stressed Holstein cows. Body condition of cows had no effect on any of the tested parameters during the thermal neutral period, except for the percentage of protein in milk. Heat stress has been demonstrated to have an impact on all the selected parameters, and has been found to be the cause of decreased milk production and quality, increased rectal temperature and respiration rate, decreased glucose, non esterified fatty acids (NEFA) and cholesterol concentration, increased urea and bilirubin concentration, and loss of subcutaneous fat. Obese cows (BCS>4) had less ability of acclimation to heat stress as compared to normal and thin cows (significantly lower production and milk quality, and significantly higher rectal temperature and respiration level in relation to the other groups of cows). Obese cows showed a significantly higher concentration of NEFA and significantly lower glucose during exposure to heat stress. The steady increase in NEFA concentrations and decrease of backfat thickness suggested that fat was used for energy purposes, which significantly increased the heat balance and led to poor acclimation to heat stress in obese cows. Cows with high body condition were at higher risk of developing liver failure and lipidosis (reduced cholesterol and elevated bilirubin concentration) during heat stress, which could be linked with increased concentrations of fatty acids in the blood. This was found with an increased concentration of urea during exposure to heat stress, with significantly higher concentration in obese cows. Using the fat for energy purposes depends on the sensitivity to insulin, which increases during heat stress. Obese cows are naturally less sensitive to insulin and more prone to lipolysis. However, these signs should be the focus of future research.Key words: Body condition score, heat stress, metabolic status, cow

    A Method of Approximate Greens Function for Solving Reflection of Particles in Plane Geometry

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    A method for approximate analytical solution of transport equation for particles in plane geometry is developed by solving Fredholm integral equations. Kernels of these equations are the Greens functions for infinite media treated approximately. Analytical approximation of Greens function is based on decomposition of the functions into terms that are exactly analytically solved and those which are approximately obtained by usual low order DPN approximation. Transport of particles in half-space is treated, and reflection coefficient is determined in the form of an analytical function. Comparison with the exact numerical solution and other approximate methods justified the proposed analytical technique

    Lienal plexus particularities

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    Catedra Anatomia Omului USMF ,,Nicolae Testemiţanu”Anatomical knowledge concerning variations of the splenic plexus in the aspects of its two main types: concentrated and diffuse, along with its topography inside the organ and its relationship with the neighboring visceral plexuses, etc. are of practical importance in performing splenectomy tactics and segmental removing of the organ. Cunoştinţele anatomice privind variabilitatea plexului lienal în contextul celor două tipuri ale lui: concentrat şi difuz, precum şi topografia intraorganica a acestuia, interrelaţiile cu plexurile viscerale alăturate etc. sunt de importanţa practică majoră în realizarea tacticilor de splenectomie şi înlăturarea segmentelor organului

    Amorphous carbon film deposition on inner surface of tubes using atmospheric pressure pulsed filamentary plasma source

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    Uniform amorphous carbon film is deposited on the inner surface of quartz tube having the inner diameter of 6 mm and the outer diameter of 8 mm. A pulsed filamentary plasma source is used for the deposition. Long plasma filaments (~ 140 mm) as a positive discharge are generated inside the tube in argon with methane admixture. FTIR-ATR, XRD, SEM, LSM and XPS analyses give the conclusion that deposited film is amorphous composed of non-hydrogenated sp2 carbon and hydrogenated sp3 carbon. Plasma is characterized using optical emission spectroscopy, voltage-current measurement, microphotography and numerical simulation. On the basis of observed plasma parameters, the kinetics of the film deposition process is discussed

    Transition Rates between Mixed Symmetry States: First Measurement in 94Mo

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    The nucleus 94Mo was investigated using a powerful combination of gamma-singles photon scattering experiments and gamma-gamma-coincidence studies following the beta-decay of 94mTc. The data survey short-lived J^pi=1+,2+ states and include branching ratios, E2/M1 mixing ratios, lifetimes, and transition strengths. The mixed-symmetry (MS) 1+ scissors mode and the 2+ MS state are identified from M1 strengths. A gamma transition between MS states was observed and its rate was measured. Nine M1 and E2 strengths involving MS states agree with the O(6) limit of the interacting boson model-2 using the proton boson E2 charge as the only free parameter.Comment: 9 pages, 3 PostScript figures included, ReVTeX, accepted for publication in Physical Review Letters, tentatively scheduled for August 9, 199
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