Cosmological constant influence on cosmic string spacetime

We investigate the line element of spacetime around a linear cosmic string in the presence of a cosmological constant. We obtain the metric and argue that it should be discarded because of asymptotic considerations. Then a time dependent and consistent form of the metric is obtained and its properties are discussed.Comment: 3 page

Lithium attenuated the depressant and anxiogenic effect of juvenile social stress through mitigating the negative impact of interlukin-1β and nitric oxide on hypothala...

Abstract—The neuroimmune-endocrine dysfunction has been accepted as one of fundamental mechanisms contributing to the pathophysiology of psychiatric disorders including depression and anxiety. In this study, we aimed to evaluate the involvement of hypothalamic–pituitary–adre nal (HPA) axis, interleukin-1b, and nitrergic system in mediating the negative behavioral impacts of juvenile social isolation stress (SIS) in male mice. We also investigated the possible protective effects of lithium on behavioral and neurochemical changes in socially isolated animals. Results showed that experiencing 4-weeks of juvenile SIS provoked depressive and anxiety-like behaviors that were associated with hyper responsiveness of HPA axis, upregulation of interleukin-1b, and nitric oxide (NO) overproduction in the pre-frontal cortex and hippocampus. Administration of lithium (10 mg/kg) significantly attenuated the depressant and anxiogenic effects of SIS in behavioral tests. Lithium also restored the negative effects of SIS on cortical and hippocampal interleukin-1b and NO as well as HPA axis deregulation. Unlike the neutralizing effects of L-arginine (NO precursor), administration of L-NAME (3 mg/kg) and aminoguanidine (20 mg/kg) potentiated the positive effects of lithium on the behavioral and neurochemical profile of isolated mice. In conclusion, our results revealed that juvenile SIS-induced behavioral deficits are associated with abnormalities in HPA-immune function. Also, we suggest that alleviating effects of lithium on behavioral profile of isolated mice may be partly mediated by mitigating the negative impact of NO on HPA-immune function. � 2015 IBRO. Published by Elsevier Ltd. All rights reserve

Air-water two-phase flow modeling of turbulent surf and swash zone wave motions

Wave breaking and wave runup/rundown have a major influence on nearshore hydrodynamics, morphodynamics and beach evolution. In the case of wave breaking, there is significant mixing of air and water at the wave crest, along with relatively high kinetic energy, so prediction of the free surface is complicated. Most hydrodynamic studies of surf and swash zone are derived from single-phase flow, in which the role of air is ignored. Two-phase flow modeling, consisting of both phases of water and air, may be a good alternative numerical modeling approach for simulating nearshore hydrodynamics and, consequently, sediment transport. A two-phase flow tool can compute more realistically the shape of the free surface, while the effects of air are accounted for. This paper used models based on two-dimensional, two-phase Reynolds-Averaged Navier-Stokes equations, the Volume-Of-Fluid surface capturing technique and different turbulence closure models, i.e., k-ε, k-ω and Re-Normalized Group (RNG). Our numerical results were compared with the available experimental data. Comparison of the employed method with a model not utilizing a two-phase flow modeling demonstrates that including the air phase leads to improvement in simulation of wave characteristics, especially in the vicinity of the breaking point. The numerical results revealed that the RNG turbulence model yielded better predictions of nearshore zone hydrodynamics, although the k-ε model also gave satisfactory predictions. The model provides new insights for the wave, turbulence and means flow structure in the surf and swash zones

Assessing changes shoreline in Dayyer city using the landsat satellite data, sensor TM and OLI 1991 and 2014 years

Coastal environments are considered the most sensitive system environments. In terms of environmental Coastal areas because of the sensitive and productive ecosystems have high importance and value. Having knowledge of the coastline’s behavior can help of the coastal better management. The aim of this study is to assessing the application of the OIF utility index factor in the assessment of coastline changes in Dayyer city, Using Landsat satellite images sensor TM and OLI 1991 and 2014 and the software are 2013®MATLAB and ArcGis 9.3. For the separation of land and water, OIF index value for all different band combinations in the application MATLAB® 2013 was calculated and then high-pass Sobel filter with 3 × 3 masks was applied to the images. Then digitization process during different periods in application environments ArcGis 9.3 was done manually and with high precision. The results of the survey the coastline from 1991 to 2014 show moving the coastline to the sea side (sedimentation) and landward (erosion), Which totals 33/784 square kilometers sedimentation and 9/132 square kilometers erosion shows from 1991 to 2014, in Dayyer city occurred because of the construction of piers, installations manmade and natural factors

Computational Simulation of Shock-Bubble Interaction, using a Front-Tracking/Ghost Fluid Method

A front tracking/ghost fluid method was used to simulate fluid interfaces in a shock–bubble interaction problem. The method captures fluid interfaces, using explicit front-tracking and defines interface conditions, using the ghost-fluid method. In order to demonstrate the accuracy and the capability tracking of the approach used, an air-helium and anair-R22 shock-bubble interaction cases were simulated. The computational results were compared with reliable experimental and computational studies, showing close agreements

Study of fish consumption per capita per year in rural and urban areas of Markazi Province, Iran

Survey method has been performed using questionnaire forms for study of fish consumption per capita per year in Markazi Province due to lack of enough data on this field in the said province. Each questionnaire was completed by asking questions from each of the families as a statistical population sample either in rural or urban areas. According to the national census in year 2008 by Iranian Statistical Center, there are 364564 families living in Markazi Province out of which 207802 (57%) families are urbanites and 156762 (43%) are ruralist. A sample with total population of 2525 families were chosen with 1455 families living in urban and 1075 families in rural areas. Systematic random sampling was adopted in both areas which show people consuming fish once in 25 days with 5.8 Kg as per capita and per year for the whole Markazi Province

Investigation of breeding and culture in Iranian cichlid (Iranocichla hormuzensis) as endemic and ornamental species

Iranian Cichlid is an invaluable ornamental species which is domesticated in Iran and called Iranocichla hormuzensis scientifically, is living in the Hormoz zone, Shahou River (between Bandar Abbas and Haji Abad). The first phase of the research project started in September of 2012 and lasted about 18 months, focused on adapting the wild cichlids to cope with the aquarium environment. Therefore, about 63 male and female of Iranian cichlids collected from the natural habitat, Shahou River, then moved to the nearest city, Bandar Abbas to and released in aquariums which were filled by water of River where they were living. After few days they moved to “innovative aquaculture technologies research station” and reared in 100 liter glass tanks to monitor their behaviors. By initial days, the Cichlids seemed to be stressed out significantly, they were flashing, hitting them to the aquarium, trying to jump out and get discolored due to strange environment. By days, the stressful treats decreased and the experiments coped with the new environment. At the next step, schools of 5-7 fish organized to pear up. The mortality rate collected daily and accidental biometry recorded fortnightly. The rearing temperature adjusted and was stable at 37˚C. Finally, the Cichlids were completely adopted and prepared for mating and breeding

The production of all-female in rainbow trout (Oncorhynchus mykiss) using indirect feminization

The sex reversal technique in fish is widespread in many countries. The development of these techniques is desirable because rainbow trout males reach their gonad maturity earlier compared to the females. Rainbow trout alevins were treated with 17α-methyltestosterone incorporated in the diet (0.5. 1.5, 3, 6 and 10 mg/kg) for 60 days from the beginning of first feeding. Sex was determined at 180 and 680 dpf by sampling fish (n = 20) from each group and examining gross gonadal morphology under a dissecting microscope. Also sex reversal ratio and growth performance were determined in hormone-treated groups. These sex reversed functional males were reared for brood stock until they attained sexual maturity. At the end of experiment, normal rainbow trout eggs were fertilized with the sperms taken from sex reversed males for producing all-female populations. Examination of the results showed that 17α- methyltestosterone was effective in all treatment. The highest sex reversal ratio with 100% was observed in group treated with 0.5, 1.5 and 3 mg/kg 17α- methyltestosterone. The highest live weight ratios were observed in groups fed with 6, 0.5 17α-methyltestosterone and control group. Female progeny produced from the sex reversed males were 100 % in all males that sired offspring. All female trout stocks produced by this method have advantage in rainbow trout culture since the fish is not meant for direct human consumption and is used to generate brood stock, therefore, difference of growth parameters do not influence the success

Cryopreservation of rainbow trout (Onchorhynchus mykiss) semen

Breeding has moved beyond the point of simply propagating random stock. Genetic potential can be improved by establishing and crossing genetically defined strains, crossing species and manipulating gametes. Some of these activities require cryopreservation of semen. Cryopreserved sperm could also be a means of exchange of genetic material between locations and populations when transportation of live fish is restricted. In this study we had a survey on rainbow trout sperm quality in Genetic and Breeding Center for Coldwatwr Fishes, Shahid Motahari, Yasouj. Then Cryopreservation trials on rainbow trout (Oncorhynchus mykiss) sperm were carried out using six basic extenders. Egg batches of 25 g were inseminated with semen frozen in five 0.5-ml straws. Thowing temperature of cryopreserved sperm also was tested. In anather trial we investigate different cryoprotectant. The result showd that the best period for sperm collection in this center was from Novamber to January. The best extender based on sperm motility parameters were extender 2 and 1 with 57.2 and 56.9% fertilisatin rates, respectively. So this two extender were used in the further experiments. The best thowing temperathre was 25°C in 30s. Testing different cryoprotectant, adding 10% methanol to extender 1 gave the highest fertilization rate (64.6%) among cryoprotectant that used with this extender. In the other extender (2) adding 5% DMSO and mixture of 5% DMSO and 1% glycerol gave the highest fertilization rates (64.8% and 67.0%, respectively). In conclusion using extender 1 and 2 with mentioned cryoprotectant and thowing rate of 25°C in 30 s was recammended for rainbow trout sperm cryopreservation