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The present study focused on ontogeny of digestive enzymes activity namely Pepsin, Trypsin and Chymotrypsin of A. stellatus. Stellate larvae, from the first day of hatch to day 50 of development, were randomly taken for enzyme assay. Specific enzyme activities of Pepsin, Trypsin and Chymotrypsin were determined. The Peptic activity was detected in one-day-old larvae with a sharp raise of enzymatic activity from day 8 post hatch forth, especially during the larval transition to exogenous feedings (p

Background: Pregnancy is associated with many emotional, physical, and social changes in women’s lives which may have an effect on the outcomes of pregnancy, so identifying moderating factors such as social support may have a preventing role on unintended outcomes of pregnancy. Objectives: The purpose of this study was to determine the relationships between social support with anxiety, depression, and stress in pregnant women. Methods: In this correlational study 249 pregnant women attending to health care centers in Zanjan-Iran, during 2015-2016 were selected using a multi-stage sampling method. Data was collected using three questionnaires including demographic characteristics, Wax social support (social support ftom family, friends, and others) and DASS-21 scale. The data were analyzed using descriptive and inferential statistics with SPSS software version 16. Results: The average age of the participants were 27.57±5.56 years. The average of total perceived social support of pregnant women was 77.42±10.66, among which the most perceived social support was from the family (29.04%). Data analyses revealed weak negative and significant relationship between total social support and depression (r=-0.17) and stress (-0.13), as well as between social support from others and depression (r=-0.14) in pregnant women (P

Abstract Background and Objective: Cystic fibrosis (CF) is an autosomal recessive genetic disease and Pseudomonas aeruginosa is one of the most common bacteria colonized in CF patients. Growing resistance of this bacterium to antibiotics now a day is a challenge of controlling infection in CF patient. In this study colonization of CF patients with Pseudomonas aeruginosa and antibiotic susceptibility pattern of isolated strains were examined. Material and Methods: From 100 CF patients, during a year, sputum and bronchial swabs were collected. After culturing the samples, some of them were reported as Pseudomonas aeruginosa using biochemical tests. Mucoid strains of Pseudomonas aeruginosa were identified the same as non-producing alginate strains while for catching single pure colony, repeated passage was used. For determining antibiotic resistance of Pseudomonas aeruginosa to some antimicrobial agents Kirby-Bauer method based on CLSI was used. Results: Of 100 samples, 40 (40%) were positive for Pseudompnas aeruginosa. The prevalence of P. aeruginosa was 23.8, 36.84 and 80% at the age of 1-3, 4-12 and 13, respectively. Conclusion: Statistically, there is a significant difference between age and contracting with Pseudomonas aeruginosa in that the higher the age the more colonization with Pseudomonas aeruginosa. Key words: Pseudomonas Aeruginosa, Cystic Fibrosis, Drug Resistance

Soil contamination with heavy metals has become a worldwide problem, leading to losses in agricultural yield and hazardous health effects as they enter the food chain . Nickel as an essential trace element, affect a number of biochemical and physiological processes in plants in toxic levels. The most common symptoms are chlorosis, and inhibited photosynthesis and respiration. Zea mays seeds were germinated and cultured on nutrient solution with nickel concentrations of 50-200 μmol for a period of two weeks. Studied physiological makers included photosynthetic pigments content, the rate of Hill reaction, K+ efflux and carbohydrate leakage from the roots to the external solution and cell death as a Ni-induced membrane damage. By increasing Ni concentration up to 100 μmol, the content of chlorophyll a increased, but decreased at 200 μmol Ni. No significant changes in chlorophyll b and carotinoids content observed.The rate of Hill reaction as an ability of chlorophyll a in the reaction center of PSII680 to split water, decreased by increasing Ni concentration. Different concentrations of nickel increased the K+ efflux and sugar leakage from roots to the culture and the cell death of root tips. The present results suggested that the disruption of photosynthesis by Ni cannot be attributed to any single factor and appears to result from its combined effects on chloroplast structure, chlorophyll content and photosynthetic protein complexes and treatment with different levels of nickel may induce structural damage and alterations in membrane properties by generation of reactive oxygen species.

In this paper, some electronic properties such as the electronic density of states (DOS), and energy band structure, and optical properties of the bulk and monolayer PtSe2 structure have been investigated based on the density functional theory (DFT) using full-potential linearized augmented plane wave (FP-LAPW) method and the modified Becke-Johnson potential (mBJ). By changing the PtSe2 structure size from bulk to monolayer, there have been major changes in the electronic (DOS and band structure) and optical properties such as the dielectric function. The electronic results show that PtSe2 in the bulk state exhibits a metallic property, while its nanosheet state, PtSe2 is a semiconductor with an energy gap of about 1.5 eV. Band structure calculations showed that for PtSe2 structure in the bulk state the energy distance between Γ-point and the K-point is about 0.4 eV, so it is concluded that PtSe2 is a semi-metal. The optical properties results show that the largest damping region for electromagnetic waves for a bulk PtSe2 structure in the z-direction is equal to 14.02 eV. The volume plasmon energy of the PtSe2 monolayer is smaller than the plasmon energy of the bulk PtSe2. Also, the optical reflectivity of the bulk PtSe2 is larger than the optical reflectivity of the PtSe2 monolayer. [ABSTRACT FROM AUTHOR]

In this paper, some electronic properties such as the electronic density of states (DOS), and energy band structure, and optical properties of the bulk and monolayer PtSe2 structure have been investigated based on the density functional theory (DFT) using full-potential linearized augmented plane wave (FP-LAPW) method and the modified Becke-Johnson potential (mBJ). By changing the PtSe2 structure size from bulk to monolayer, there have been major changes in the electronic (DOS and band structure) and optical properties such as the dielectric function. The electronic results show that PtSe2 in the bulk state exhibits a metallic property, while its nanosheet state, PtSe2 is a semiconductor with an energy gap of about 1.5 eV. Band structure calculations showed that for PtSe2 structure in the bulk state the energy distance between Γ-point and the K-point is about 0.4 eV, so it is concluded that PtSe2 is a semi-metal. The optical properties results show that the largest damping region for electromagnetic waves for a bulk PtSe2 structure in the z-direction is equal to 14.02 eV. The volume plasmon energy of the PtSe2 monolayer is smaller than the plasmon energy of the bulk PtSe2. Also, the optical reflectivity of the bulk PtSe2 is larger than the optical reflectivity of the PtSe2 monolayer. [ABSTRACT FROM AUTHOR]

Objective(s): To examine knowledge and practice of female students about function, dietary sources, effective factors on iron absorption, causes and symptoms of iron deficiency. Methods: In a cross-sectional study 500 female students were selected by random sampling from high schools of district 6 in Tehran. Data were collected by a self-administered questionnaire including items on general knowledge and practice about dietary iron. Results: The knowledge scores of students about dietary iron were low. The association between knowledge scores and studentschr('39') grade, field of study and previous yearchr('39')s credit were significantly different (P