German Science Center for the Solar Dynamics Observatory

A data and computation center for helioseismology has been set up at the Max Planck Institute for Solar System Research in Germany to prepare for the SDO mission. Here we present the system infrastructure and the scientific aims of this project, which is funded through grants from the German Aerospace Center and the European Research Council

Magnetic Fields and Afterglows of BdHNe: Inferences from GRB 130427A, GRB 160509A, GRB 160625B, GRB 180728A and GRB 190114C

GRB 190114C is the first binary-driven hypernova (BdHN) fully observed from the initial supernova appearance to the final emergence of the optical SN signal. It offers an unprecedented testing ground for the BdHN theory and it is here determined and further extended to additional gamma-ray bursts (GRBs). BdHNe comprise two subclasses of long GRBs with progenitors a binary system composed of a carbon-oxygen star (CO$_\textrm{core}$) and a neutron star (NS) companion. The CO$_\textrm{core}$ explodes as a SN leaving at its center a newborn NS ($\nu$NS). The SN ejecta hypercritically accretes both on the $\nu$NS and the NS companion. BdHNe I are the tightest binaries where the accretion leads the companion NS to gravitational collapse into a black hole (BH). In BdHN II the accretion onto the NS is lower, so there is no BH formation. We observe the same structure of the afterglow for GRB 190114C and other selected examples of BdHNe I (GRB 130427A, GRB 160509A, GRB 160625B) and for BdHN II (GRB 180728A). In all the cases the explanation of the afterglow is reached via the synchrotron emission powered by the $\nu$NS: their magnetic fields structures and their spin are determined. For BdHNe I, we discuss the properties of the magnetic field embedding the newborn BH, inherited from the collapsed NS and amplified during the gravitational collapse process, and surrounded by the SN ejecta.Comment: 7 figures, 3 tables, submitted to Ap

A theory of non-local linear drift wave transport

Transport events in turbulent tokamak plasmas often exhibit non-local or non-diffusive action at a distance features that so far have eluded a conclusive theoretical description. In this paper a theory of non-local transport is investigated through a Fokker-Planck equation with fractional velocity derivatives. A dispersion relation for density gradient driven linear drift modes is derived including the effects of the fractional velocity derivative in the Fokker-Planck equation. It is found that a small deviation (a few percent) from the Maxwellian distribution function alters the dispersion relation such that the growth rates are substantially increased and thereby may cause enhanced levels of transport.Comment: 22 pages, 2 figures. Manuscript submitted to Physics of Plasma

Effects of ferulic acid and grape seed extract treatment on black spot of whiteleg shrimp (Litopenaeus vannamei) during freezing period

Aims and literature review: Effects of ferulic acid and grape seed extract for preventing black spots forming in whiteleg shrimps and its replacement rather than by synthetic compounds. So far to prevent black spots on shrimp by grape seed extract and Frulic acid has not been investigated in Iran. Material and methods: Three treatments were used to implement this study. The treatments contained immersed shrimp ferulic and and grape seed extract (at a concentration of 3 % and 1.5%, respectively) for 15 minutes and without antioxidant shrimp. Qualities of samples had been evaluated by chemical and sensory tests at a temperature of -18 °C in frozen storage for 6 months. Results: Peroxide value, Thiobarbituric acid, free fatty acids and TVB-N factors showed significant differences compared to control samples (p0.05). Sensory factors including color (melanosis) of ferulic acid and grape seed extract treatment showed significant difference compared to control samples. Sensory quality and shelf life of no observed significant difference in ferulic acid compared to grape seed extract (p>0.05). Black spot wasn't formed in the experimental treatments till the end of the storage period but melanosis was formed in the control samples in less than a month being kept in frozen storage

Evaluation of Carotenoids and Chlorophyll as Natural Resources for Food in Spirulina Microalgae

Microalgae can produce various natural products such as pigments, enzymes, unique fatty acids and vitamins that benefit humans. The objective of the study was evaluation of carotenoids (beta carotene, zeathanthin, lutein, lycopene and astaxanthin) and chlorophyll a in spirulina microalgae. Spirulina powder has been produced by Jordan’s method in Iran. Carotenoids were extracted from Spirulina platensis by adopting a method described by Reboul; then the sample was prepared and injected into a HPLC instrument with triplicate injection. Chlorophyll`s biomass content was determined by spectrophotometer. After assaying the curves of HPLC, the amount of chlorophyll a, astaxanthin, beta carotene, lycopene, zeaxanthin and lutein in spirulina was determined as 4.3±0.14, 0.21±0.02, 7393±2.76, 741±2.32, 6652±3.69 and 424±2.83 μg/ml respectively. Beta carotene account for 80% of the carotenoids present in spirulina after that zeaxanthin was most. At last, Spirulina was a good source for carotenoids as a pro-vitamin A in organisms

Theoretical studies of ethylnitrolic acid using Gaussian

The tautomerism of all possible forms of ethylnitrolic acid was investigated theoretically in various environment including gas phase, ethanol, dimethyl sulfoxide (DMSO) and water. The calculations were carried out at DFT/B3LYP and MP2 of theory singly. It was found that, form of B eythynitrolic acid is the most stable isomer in the both gas phase and solvent. The activation energies for conversion of A to R and B to A in the gas phase and solvent using two methods DFT/B3LY and MP2 were obtained. Geometrical parameters of three isomers, A, B and R, were calculated by (DFT/B3LYP and MP2) in the gas phase and solvent. Vibrational analysis and acidity constants (PKa) of two isomers (A and R) were computed in the gas phase and water using DFT/B3LYP and MP2. After that, these quantities were evaluated with experimental values and it was determined that DFT/B3LYP is more accurate to obtain PKa.Keywords: Tautomerism; ethylnitrolic acid; solvent effect; proton transfer reaction; acidity constant

A Fractional Fokker-Planck Model for Anomalous Diffusion

In this paper we present a study of anomalous diffusion using a Fokker-Planck description with fractional velocity derivatives. The distribution functions are found using numerical means for varying degree of fractionality observing the transition from a Gaussian distribution to a L\'evy distribution. The statistical properties of the distribution functions are assessed by a generalized expectation measure and entropy in terms of Tsallis statistical mechanics. We find that the ratio of the generalized entropy and expectation is increasing with decreasing fractionality towards the well known so-called sub-diffusive domain, indicating a self-organising behavior.Comment: 22 pages, 14 figure

Derivation of extracts from Persian Gulf sea cucumber (Holothuria leucospilota) and assessment of its antifungal effect

Sea cucumber is presented as a potential marine source of antimicrobial compounds. The purpose of this study is to evaluate antifungal effects of sea cucumber, Holothuria leucospilota, extracts on Aspergillus niger and Candida albicans. Methanol and chloroform extracts of the body wall, gonad and intestine of sea cucumber, H. leucospilota, collected from Persian Gulf, were evaluated for their antifungal activity against A. niger and C. albicans. The activity was determined using serial dilution method. Antifungal activity, minimum inhibitory concentration and minimum fungicidal concentration were evaluated by the different concentrations. Results showed that each of the extracts had antifungal effect at specified concentrations on the A. niger. All examined concentrations of Gonad methanol and intestine chloroform extracts had no inhibitory effect on C. albicans. Chloroform extracts of gonad and intestine had more fungicidal effect against A. niger compared with C. albicans. Gonad chloroform extracts showed more fungicidal effect on the C. albicans at concentrations of 2.5, 5 and 10 mg/ml. Sea cucumber extract can be considered as an antifungal agent in various industries such as medicine and pharmaceutical industry

Cytotoxic activity of natural components soluble in methanol and diethyl ether of Dysidea pallescens from Hengam Island, Persian Gulf

Sponges are the most primitive of the multicellular, These organisms don’t have any mechanical defense system, so their early appearance in evolution has given them a lot of time for the development of advanced secondary metabolites as chemical defense system. Sponges have the potential to provide drugs from chemical components against diseases. In this investigation the sponge samples, which it is Dysidea pallescens, were collected at depth of 15- 20 meter, from locations on the coastline of Island Hengam in Persian Gulf of Iran. For identifying natural components, methanol and diethyl ether were used as extraction solvents, after removal of the solvents; the in vitro cytotoxic activity was identified. In vitro cytotoxicity screening, by XTT assay, against KB/ C152 and HUT-78/ C185 cell line, was conducted in this study in 1 - 500 µg/ml. IC50 for diethyl ether and methanol extract was 200 µg/ml in HUT-78, IC50 for diethyl ether extract was 325µg/ml and methanol extract 325µg/ml in KB