Shear viscosity of superfluid 3He-A_1 at low temperatures

The shear viscosity tensor of the A_1-phase of superfluid 3He is calculated at low temperatures and melting pressure, by using Boltzmann equation approach. The two normal and superfluid components take part in elements of the shear viscosity tensor differently. The interaction between normal and Bogoliubov quasiparticles in the collision integrals is considered in the binary, decay and coalescence processes. We show that the elements of the shear viscosities $\eta_{xy}$, $\eta_{xz}$ and $\eta_{zz}$ are proportional to $(T/T_c)^{-2}$. The constant of proportionality is in nearly good agreement with the experimental results of Roobol et al.Comment: 16 pages, some typos were correcte

Effects of biaxial strain on the intervalence‐band absorption spectra of InGaAs/InP systems

The effects of biaxial strain on the intervalence‐band absorption spectra of p‐doped InGaAs/InP bulk layers are investigated. The study is performed by calculating and comparing the absorption coefficients corresponding to the direct transitions between the heavy and light hole bands, between the heavy hole and split‐off bands, and between the split‐off and light hole bands in both the lattice matched and the strained layers. The valence‐band structures of these layers are neither isotropic nor parabolic and hence the k⋅p approach is utilized to calculate the band structures and their corresponding wave functions. The quantities are then invoked in the calculation of the (joint) density of states, the Fermi energy, and the momentum matrix element, which are needed in the evaluation of the intervalence‐band absorption coefficients. These calculated results show that the intervalence‐band absorption coefficients depend on the strain in the layer. The dependence is determined by the bands involved in the intervalence transition, the polarization of the incident light, and the type of the strain (compressive or tensile). © 1995 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70188/2/JAPIAU-77-12-6549-1.pd

Chemotype of damask rose with oleic acid (9 octadecenoic acid) and its antimicrobial effectiveness

Essential oils are natural products that have great antimicrobial potential value against many fungi and bacteria. Rosa damascena Mill. is one of the most important aromatic species of the Rosaceae family from which essential oil and economically valuable products can be obtained. The present study was designed to investigate the major compositions of the essential oil of this plant in Isfahan region of Iran and to identify its antibacterial and antifungal effects against 11 microorganisms causing human diseases and food spoilage. The essential oil was extracted by using the Clevenger apparatus and was analyzed by gas chromatography-mass spectrometry (GC–MS) technique. Its antimicrobial activity was evaluated by well diffusion, minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). The results showed that the most important compounds of the essential oil were nonadecane (24.72%), heneicosane (19.325%), oleic acid (17.63%), and citronellol (12.61%). The results also showed that the highest inhibition zone of rose essential oil was against Aspergillus brasiliensis (15.00 ± 0.00 mm) and had a significant effect on Klebsiella pneumoniae (~ 8.00 mm). Also the rose oil had a significant inhibition and lethal effect against Candida albicans (MIC and MBC ~ 125 μg/mL), which is equivalent to the nystatin antibiotic (~ 125 μg/mL). Therefore, the essential oil of Damask rose can be considered as an alternative natural product for the prevention and treatment of fungal diseases in humans and against food spoilage as well

Governments need better guidance to maximise value for money: the case of Australia’s Pharmaceutical Benefits Advisory Committee

Published online: 27 January 2016In Australia, the Pharmaceutical Benefits Advisory Committee (PBAC) makes recommendations to the Minister for Health on which pharmaceuticals should be subsidised. Given the implications of PBAC recommendations for government finances and population health, PBAC is required to provide advice primarily on the basis of value for money. The aim of this article is twofold: to describe some major limitations of the current PBAC decision-making process in relation to its implicit aim of maximising value for money; and to suggest what might be done toward overcoming these limitations. This should also offer lessons for the many decision-making bodies around the world which are similar to PBAC. The current PBAC decision-making process is limited in two important respects. First, it features the use of an implicit incremental cost-effectiveness ratio (ICER) threshold that may not reflect the opportunity cost of funding a new technology, with unknown and possibly negative consequences for population health. Second, the process does not feature a means of systematically assessing how a technology may be of greater or lesser value in light of factors that are not captured by standard measures of cost effectiveness, but which are nonetheless important, particularly to the Australian community. Overcoming these limitations would mean that PBAC could be more confident of maximising value for money when making funding decisions.Drew Carter, Arlene Vogan, Hossein Haji Ali Afzal

Shear viscosity of the A_1-phase of superfluid 3He

The scattering processes between the quasiparticles in spin- up superfluid with the quasiparticles in spin-down normal fluid are added to the other relevant scattering processes in the Boltzmann collision terms. The Boltzmann equation has been solved exactly for temperatures just below T_c_1. The shear viscosity component of the A_1- phase drops as C_1(1-T/T_c_1)^(1/2). The numerical factor C_1 is in fairly good agreement with the experiments

SIMULTANEOUS SEPARATION AND PRECONCENTRATION OF TRACE AMOUNT OF COPPER, NICKEL, CADMIUM AND ZINC IONS ONTO MODIFIED AMBERLITE XAD-4 LOADED WITH 5-Br-PADAP

In this work, a simple, rapid, selective, sensitive and economical method has been developed for the simultaneous separation and preconcentration of trace amounts of copper, nickel, cadmium, and zinc in aqueous medium using XAD-4 resins that were modified with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) as an analytical reagent. The sorption is quantitative in the pH range 7.0-9.5, whereas quantitative desorption occurs instantaneously with 2 M HCl and selected trace elements have been determined using flame atomic absorption spectrometry. The linearity is maintained between 0.04-4.0 mg L-1 for copper, 0.1-4.0 mg L-1 for nickel, 0.02-1.3 mg L-1 for cadmium and 0.01-1.4 mg L-1 for zinc. The detection limits were 12 μg L-1 for Cu(II), 30 μg L-1 for Ni(II), 6 μg L-1 for Cd(II), and 4 μg L-1 for Zn(II) in the final solution. Various parameters such as the effect of pH, flow rate, breakthrough volume and interference of a large number of anions and cations have been studied and the proposed method was used for determination of these metal ions in water and standard samples. In order to compare the proposed method, the actual water samples were analyzed by direct FAAS (using standard addition method). Determination of these metal ions in standard samples confirmed that the proposed method has good accuracy. KEY WORDS: Simultaneous separation and preconcentration, Determination of Cu, Ni, Cd, and Zn, Amberlite XAD-4 resins modified with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP), Analytical reagent Bull. Chem. Soc. Ethiop. 2006, 20(1), 1-7

Antioxidant status, immune system, blood metabolites and carcass characteristic of broiler chickens fed turmeric rhizome powder under heat stress

This experiment was conducted to evaluate the effects of dietary turmeric rhizome powder (TP) on performance, blood metabolite, immune system, antioxidant status, and relative weight of organs in pre and post heat stressed broilers. Two hundred and sixty-four (264) day-old male Arian broiler chicks were randomly allotted to three dietary treatments containing 0, 0.4 or 0.8% turmeric powder. Each diet was fed to four replicates of 22 birds each. Heat stress was applied for 5 h (33°C) from 28 to 42 days. Two birds from each replicate were randomly selected and blood samples were taken to collect the serum, plasma and whole blood. These were slaughtered to determine the relative weight of organs pre (28 days PHS) and after heat stress (42 days AHS). TP did not affect feed intake, body weight, feed conversion ratio (FCR), production index, and protein and energy efficiency ratio of broilers. Blood cholesterol and low density lipoprotein (LDL) decreased and blood high density lipoprotein (HDL) increased when fed TP in PHS and AHS birds. TP did not affect serum triglyceride, protein, antibody production against sheep red blood cell (SRBC), IgG, IgM and Newcastle vaccination (ND) in PHS and AHS. TP suppressed the enzyme activity of lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) of heat stressed birds. The enzyme activity of creatine kinase (CK) in AHS and superoxide dismutase (S OD) in PHS were not affected by TP diets. TP diets increased blood activity of glutathione peroxidase (GPx) and SOD and decreased blood thiobarbituric acid reactive substances (TBARS) index. The H:L ratio, relative weight of bursa of fabircus and abdominal fat decreased in birds fed TP diets. TP diets did not alter percentage of bone Ash, and P of heat stress broilers; however, it increased bone Ca of heat stressed broilers. It can be concluded that the supplementation of TP to diets, decreased the activity of dehydrogenase enzyme, stressor index, and improved the antioxidant status without affecting performance and the immune system of heat stressed broilers.Key words: Turmeric powder, immune and antioxidant system, blood metabolite, broiler