Seasonal variation of zooplankton abundance, composition and biomass in the Chabahar Bay, Oman Sea

Temporal and spatial variation of zooplankton abundance, composition and biomass were examined on the Chabahar Bay, Oman Sea. The Chabahar Bay, a subtropical and semi-enclosed bay, provides an ideal breeding ground for many fish and shellfish. Five stations were investigated along the Bay. This area is under the influence of the Indian Ocean seasonal monsoons. Zooplankton was collected with vertical plankton tows using 100 µm mesh nets. Copepods dominated the zooplankton community followed by larvacea, cladocera and chaetognatha. Fifteen taxa of zooplankton were identified. Oithona nana and Euterpina acutifrons were dominated in the whole year and Larvacea showed a bloom in Northeast Monsoon. A Two-way ANOVA indicated that there were differences in abundance and biomass between sampling periods and between stations were significant. The peak zooplankton abundance in NE Monsoon could be due to winter cooling, with entrainment of nutrients into the upper layer producing phytoplankton blooms. The decline of zooplankton abundance and biomass in South West Monsoon and post-monsoon could be explained by decrease in chlorophyll a concentrations. The present result showed the composition and distribution of zooplankton differed between the monsoon seasons, resulted from changes in hydrographic conditions

Ovarian development of Caspian roach, Rutilus caspicus, in southern Caspian Sea: A histological and ultrastructural study

The histology and ultrastructure of the ovarian maturation process in Caspian roach, Rutilus caspicus, was studied. A total 170 female specimens were collected from the Gharasoo River, Bandar Turkmen, the southern Caspian Sea to evaluate its maturation cycle. Based on the results, its ovarian follicle’s development could classified into six stages by distinct characteristics. Minimum and maximum diameter of oocytes were recorded in the chromatin-nucleolus and maturation stages as 56.34±3.74 and 918.83±14.82 µm, respectively. The zona radiata was observed from the cortical alveoli stage and its maximum diameter measured in the secondary vitellogenesis stage as 93.11±23.0 µm. Gonadosomatic index (GSI) reached to its peak in mid-March and its sharp drop in the late April showed its spawning period from late March or early April till the end of April. A positive correlation was found between the GSI and HSI in the vitellogenesis stage. The results also revealed Caspian roach as iteroparous synchronous spawner

The impact of social capital to improve rural households’ resilience against flooding: evidence from Iran

Floods have significantly affected many regions worldwide, imposing economic, social, and psychological consequences on human societies, in recent decades. Rural communities in Iran are particularly vulnerable to floods, and without effective risk reduction systems, the impact can be exacerbated. In this context, this study aims to investigate the role of social capital in enhancing the resilience of rural households against floods in the southwest of Iran. The statistical population includes all rural households in Shushtar County that have experienced floods at least once. The primary tool for data collection was a questionnaire and obtained data were analyzed using structural equation modeling. In examining the situation of confrontation between different groups of people based on the state of social capital and resilience, it can be said that men, older people and people with higher income had more resilience and social capital to deal with floods. In addition, the results revealed that components of social capital (social networks, social solidarity, social trust, social awareness, participation and collection action) explained 68.1% of the variance in the resilience of rural households against floods. Overall, our findings can provide new insights for policymakers in the area, contributing to the reduction of flood impacts and promoting safer living conditions in flood-prone areas

Study of morphological charachteristic and distribution of Indomysis annandalei and Rhopalophthalmus sp. (Crustacea: Mysida) for the first time from Iranian costal of Persian Gulf

Mysida includes small planktonic Crustaceans that are cosmopolitan, this tiny animals could be found in variety of marine habitats and depts. In this investigation mysida populations were sampled and studied from Iranian costal waters of Persian Gulf (estuary of Arvand and Bahmanshir rivers) in monthly basis from March to October 2011. Sampling process was conducted using plankton net 300 µm mesh size and oblique tows were made from near the bottom to the surface in 7 stations. Finally two species identify and morphological charachteristic of Indomysis annandalei and Rhopalophthalmus sp. was drew with Camera Lucida. Species abundance was measured in different months and stations. Maximum value of the average abundance of species was shown in June (2.85 1 N per M^3)

Alterations in histological structure, blood estrogen and progesterone levels after oral administration of garlic extract in yellowfin seabream (Acanthopagrus latus)

In this study, the effects of garlic phytoestrogen extract on gonad maturation along with estrogen and progesterone levels in yellowfin seabream (Acanthopagrus latus) were investigated. A total of 60 yellowfin seabreams were caught from Naseri pond in Khuzestan Province, Southwest Iran and transported to the laboratory. Fish were treated in four groups receiving garlic extract with doses of 0 (control), 0.5, 1 and 2 % of diet (T1, T2 and T3, respectively). Each treatment consisted of three replicates. The fish were fed twice a day at 3% of body weight for 14 days. For histological study, samples were taken from the gonads. In order to assay the hormone levels, samples were taken from the caudal vein of the fish on days 0, 7, 10 and 14. The histological results showed that garlic extract in the lowest dose caused a decrease in vitellogenesis, however, in higher doses an elevation in vitellogenesis and also the tendency of this hermaphrodite fish gonads to be female. The highest amount of vitellogenesis was reported in T1 on 10th day. In total, elevating in the amount of this extract initially upraised the number of vitellogenic follicles and promotion of ovarian maturation. However, higher doses and also increasing the administration time of the extract exhibited inverse results. Measuring the levels of hormones showed a significant change in their plasma levels during the experiment, so that an increase in level of estrogen was observed in all three prescribed doses and an increase in level of progesterone was observed in higher doses (T2 and T3; p<0.05). The results of the present study indicate the effect of garlic phytoestrogen extract on growth and maturation of ovaries

Heavy metal Concentration in Belanger&apos;s Croaker Fish, Johnius belangerii from Petrochemical Waste Receiving Estuary in the Persian Gulf, Iran

Abstract. Musa Estuary is receives various type of discharges such as petrochemical, industrial and urban waste, it also is a habitat for Johnius belangerii. This study was carried out to determine heavy metal concentrations in J. belangerii. Fish samples were taken from 5 creeks and acid digested for their heavy metal contents. Results showed that the highest level of Cd, Co, Cu, Ni and Pb was 7.21, 1.08, 1.12, 2.72 and 4.57 in liver, 1.88, 1.04, 2.09, 9.43 and 6.83 in gill and 0.14, ND, 5.61, 2.43 and 3.78 in muscle respectively. The level of heavy metals in muscle was lower than WHO standard, however the level of metals in fish were decreased by the increase of distance from PETZON. It is suggested that biomonitoring of contaminants in this estuary could serve as a good estimate of environmental health

Biological activity (antibacterial, antifungal, antiviral and cytotoxic) of extract from Dysidea spp.

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 alot 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 spp. , 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, methanolic and diethyletter were used as extraction solvents, after removal of the solvents, the GC/MS spectra of the fraction were obtained. Then in vitro cytotoxic, antimicrobial, antifungal and antiviral activities were identified. In vitro cytotoxity 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 diethyletter and methanolic extract was 200 µg/ml in HUT-78 , IC50 for diethyletter extract was 325µg/ml and methanolic extract 325µg/ml in KB. In vitro antimicrobial activity by Broth Dilution Methods against clinical gram-positives and gram negatives (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus و subtilis Bacillus). The results conducted that the MIC values of methanol and diethyletter extract for Escherichia coli 20mg/ml, Bacillus subtilis 10mg/ml and 2mg/ml for Staphylococcus aureus. The MBC values of the diethyletter extracts for Bacillus subtilis 30 mg/ml) and S. aureus aureus 10mg/ml. In vitro antifungal activity by Broth Dilution Methods against clinical pathogens; Candida albicans and Aspergillus fumigatus. The results conducted that the aqueous extracts didn’t have any antifungal activities on pathogens, minimum inhibitor concentrations (MIC) of the diethyletter extract on C. albicans 0/75mg/ml, MFC 5 mg/ml and methanolic extract 0.5mg/ml and MFC 5 mg/ml on A. fumigatus In vitro antiviral activities by XTT assay against MT-2 cell line. The results conducted that IC50 for diethyletter extract 500µg/ml and methanolic extract 475 µg/ml

Ecophysiology of the common cockle (Cerastoderma edule L.) in Southampton Water with particular reference to pollution

Ecophysiological studies encompassing many aspects of population ecology and individual physiological functions on Cerastoderma edule have been carried out. Sites for study were carefully selected so as to include both areas in the proximity of a pollution source (i.e. Fawley, Tucker Pile, Bird Pile and Marchwood) and regions distant from overt polluting input (Dibden Bay, Netley and Woolston). In the sheltered central parts of the estuary longevity, abundance, growth rates and productivity were higher. In contrast most localities on the western side of the estuary showed reduced growth, abundance, longevity and productivity. The variation observed in the population parameters was attributed to pollution load (heavy metals and petroleum hydrocarbons) and other sediment properties (grain size and organic matter content) of sites. The results of seasonal, age and site to site variation in the concentrations of six heavy metals (copper, cadmium, lead, iron, nickel and zinc) in C.edule tissues and sediment indicate that the populations inhabiting areas in the proximity of the industrial complex are more contaminated than those outside the areas. The same trend was found for the total petroleum hydrocarbons of cockles and sediment; being highest at Fawley and Tucker Pile. Statistical analysis of data supported the idea that the variability in the concentrations of copper, zinc, petroleum hydrocarbons and sediment grain size bring about the differences observed in the population parameters. Based on the levels of these variables, four site groups were identified. The physiological impact of pollution on C.edule was studied in greater detail. The effect of the water-accommodated fraction of Fawley oil and copper concentrations was marked on the clearance rate and absorption efficiency. Cockles exposed to higher concentrations showed negative scope for growth after the second week of exposure. A highly significant inverse correlation was found between either the concentration of WAF or Cu and the scope for growth. The physiological conditions of C.edule in the field were also investigated. The measurements were carried out on the populations of cockles at Fawley (a polluted site) and Dibden Bay (a relatively uncontaminated site). The energy available for the growth of cockles inhabiting Dibden Bay was found to be ten times greater than that available to Fawley cockles. The body condition index measured for the cockles along Southampton Water throughout the year showed similar variance as that displayed for scope for growth. Finally, the results of the present study were discussed in relation to event in the natural habitat of cockles in Southampton Water.</p

Analyzing Price Discovery Function of Gold Coin Futures Contracts in Iran

This paper deals with the question of whether gold coin futures contract in Iran performs expected function of price discovery or not. We investigate this question by using three distinct approaches: linear and nonlinear causality tests between gold coin futures and spot market, volatility spillovers between those markets and share of each market in the process of price discovery. The data cover two periods: 1 August 2011 - 24 November 2013 and 25 November 2013 - 16 July 2015, with the former period corresponding to the unprecedented volatility of gold coin market in Iran and the latter period corresponding to stability of this market. In general, the results show that causality runs from spot prices to futures prices, volatility transmits from spot market to futures market and price discovery takes place mainly in spot market. Overall, the results of this paper reveal that futures market does not perform the expected function of price discovery. The results are consistent with the basic characteristics of futures market in Iran: it is in the early stages of its development and its size, in comparison to the spot market, is small

Using Mixed Integer Linear Programming Model For Beam Angle And Fluence Map Optimization In Intensity- Modulated Radiation Therapy

Introdution: Intensity- modulated radiation therapy is one of the treatment methods for cancer tumors. The effectiveness of this method is dependent on the accuracy and treatment planning quality. Therefore, there is a need for a plan to select the angle and intensity simultaneous optimum of radiation. Methods: In this study, an mixed integer linear programming model was proposed for simultaneous optimization of angles and intensity in the GAMS programming environment.To implement the model, after the patient's CT was prepared, the organ cantoring was performed by CERR software and the Influence Matrix was obtained for each organ. After collecting the inputs of the problem, in order to obtain the desired outputs, was used&nbsp; from The GAMS software from the CPLEX solver. Results: Finally, the actual case of head and neck cancer is analyzed to demonstrate the effectiveness of the model. From the angle of the candidate, ، is chosen as the optimal radiation angles. The maximum dose received by the brainstem was 3. 999, Mandible 70, LeftOrbit 0.026, RightOrbit 0.440, Parotid Gland 0.881, OpticChiasm 0.177, OpticNerves 0.167, spinalcord 9.929 Gray and the minimum dose received by the tumor is 70 Gray. Also, the optimal amount of intensity for implementing the treatment plan on the patient is achieved. Conclusion: The dose received by each organ was significantly improved compared to prescribing doses. Similarly, the comparison of the Dose Volume Histogram obtained by solving a common problem with the model and software CERR, Represents the optimal performance of the model, which improves the security rate and reduces the cost for healthy tissues