12 research outputs found

    The percentage determination of Rutilus frisii kutum (200, 500 and 1000 mg) resistance to salinity, turbidity and decrease of oxygen by usage of the river water at the releasing meantime

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    The survey effect of salinity, turbidity and dissolved oxygen performed on Rutilus frisii Kutum juveniles with aim, which was determined about survival rate and histological changes in gill and kidney tissues. Juveniles provided from the Rajai's fish propagation center and then examined in Caspian Sea Ecology Research Center laboratory. The juveniles were investigated on three weight group (200-75%) had shown in 400-<600mg weight group with dissolve oxygen: 3.8±0.15SE mg/l. In addition, the lowest survival rates under turbidity stress (95.83%) had shown that in weight group less than 400 mg with turbidity 15600 FTU. Therefore, survival of juveniles was high. However, gill tissue of juveniles under turbidity and salinity stress became short (necrosis) and thick (edema and hyperplasia) in the end of experiments. The juveniles gill tissues were not changes in the river clear freshwater. Therefore, the factors of gill tissue deformation were salinity and suspended particles in the water. However, the structures of kidney in the different groups of juveniles were similar. Nevertheless, juveniles glomerular diameter increased with increasing weight (p<0.05, Duncan test). Furthermore, there was a increasing the internal cavity of the proximal and distal tubules and decreasing of glomeruli in diameter in the transfer of juveniles from freshwater to brackish water. Although the survival rate of juveniles is acceptable in this study, but there was abnormal changes in the structure of them gills. It appears that this change will cause a disruption in trend of juvenile's growth

    Evaluation of quantitative and qualitative of microbial indicator the lake behind Shahid Rajaee dam of Mazandaran province (Sari)

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    One of the country's dams is dam Shahid Rajaee Sari. In this study it was evaluated some bacterial indices. Some bacterial parameters including total bacteria, total coliform, fecal coliform, fecal streptococci , Sulphitereducing Bacteria (SRB) in the water behind the dam Shahid Rjaee for one year at five stations (the entrance Shireenrood branches, input branch of the Sefidrood, cross the river and sweet Sefidrood in the tank, close to the Taj (zero, 15 and 30) and the output reservoir) and seven samples collected during six periods (June, July, August, September, November and February) were tested in 1391. Analysis of water samples for bacterial plate count agar medium (total bacteria count) ECC were inoculated (total coliforms and fecal), SPS (sulfite reducing bacteria) and KF (bacteria Inserts fecal streptococci) was performed using the culture surface culture method. ECC in both 37 and 44 ° C medium temperature Tc, KF and SPS at 37 ° C for 72-24 hours were incubated. The results showed that the mean log of bacteria in different months of CFU / 100ml12 / 0 ± 85/6 1n September months to CFU100ml15 / 0 ± 65/4 is variable in February, the mean total coliform Log in of the CFU / 100ml15 / 0 ± 63/4 in September to CFU / 100ml44 / 0 ± 27/3 in February are variable, the mean log Clostridium Clostridium CFU / 100ml89 / 0 ± 17 / 4 in September to CFU / 100ml13 / 0 ± 07/3 in February is variable, ranging from the mean log reduction in fecal streptococci in different months CFU / 100ml19 / 0 ± 59/3 in September CFU / 100ml17 / 0 ± 10 / 3 in February is variable. The results showed that bacterial indicator pollution load of the dam in more stations in August and September months. . Compare the results of the surface water standards indicate that indicator bacteria have been studied in the standard range. If the water behind the dam is intended to be used for drinking, it has need for more treatments during the final purification for drinking purposes

    Evaluation of stocking density vannamei shrimp Litopenaeus vannamei (Boone, 1931) in culturing with brackish water of Caspian Sea

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    Recently, the development of aquaculture has focused on the use of seawater, because of freshwater crisis in the world. Whiteleg shrimp (Litopenaeus vannamei) is one of the most important species for aquaculture development, because of tolerance and adaptation to different ecological conditions. One of the advantages of species in aquaculture, compatibility status is dense in the rearing period. In this study, the effect of different densities (45/m^2 , 50/m^2 , 55/m^2 and 60/m^2 ), of primary stock whiteleg shrimp postlarvae (PL12) on the growth and survival rate were evaluated. Brackish water (10.52±0.43 ppt) was providing from Caspian Sea. The experiments were performed in 12 circular concrete pond with a sandy bed (area: 78m^2 ) in four treatments and three replications for each treatment. The experiments performed in a 75-day period. In this study, the water temperature was 27.4±1.79°C. The results showed statistically difference in growth parameters and survival rate among experimental treatments (Duncan test, P<0.05). Therefore, with high levels of density, has decreased the amount of weight gain and survival rate (SR), specific growth rate (SGR) and average daily growth (ADG). In addition, the treatments were different variations of FCR (P<0.05) and not depend on the primary stock density of postlarvae. In low density (45/m^2 ) were observed the highest growth (SGR=11±0.04 and ADG=0.25±0.01 gr/day/ind.), survival rate and calculate the amount of production per 78m2 equal 43.6±3.3kg (5596±433kg/ha). Therefore, It is possibility that there is commonly increasing primary stocking of density about L. vannamei postlarvae culture in Iran

    Survey and feasibility study for the introduction of native fish and non- native fish for cage culture in the southern part of Caspian Sea

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    The aim of this study is the feasibility of introducing suitable species of fish (native and exotic) for rearing in cages in the southern region of the Caspian Sea. This study from the perspective of economic efficiency and maintaining ecology were analyzed. The results showed that the southern Caspian Sea has the ability to aquaculture fish. However, due to the yearly temperature variations of water (from surface to a depth of 50 meters), the talent of aquaculture area is preferred for fish in cold water than warm water fish due to possibility rearing over the years. The survey showed that the current conditions and due to unfavorable changes in the ecology of the area in the last decade, the use of non-native fish culture in cages is not recommended. Many species of native fish are suitable for rearing in cages. Nevertheless, there is no infrastructure suitable for the production of all of them. Therefore, respectively species of Salmo caspius, Huso huso and Common carp of Caspian Sea for cultivation of in cages was suggested. In the current situation, this fish for their ability to grow faster than the need for selectivity. It is noteworthy that detailed environmental assessments and species risk assessments before the final introduction of any fish species (native and exotic) for rearing in cages in the Caspian Sea ecosystem is essential

    A survey on health status of coldwater rearing and hatcheries fish farms in Iran (Mazandarn, Gilan, Ardebil, West Azerbaiejan, East Azerbaiejan and Kordestan provinces)

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    The national research plan with title of "Study on health status of Iran Coldwater hatchery and rearing farms" was done in order to identification and tracking of main causative agents of recent mortality in Iran Coldwater hatchery and rearing farms and recognize of infected zones and design of landscape distribution of Epizootic Coldwater fish diseases in the country. This plan was conducted parallel and in same time in some polar provinces of Coldwater fish production such as Mazandaran, Gilan, Ardebil, West Azerbaijan, East Azerbaijan and Kurdistan in three years from 2006-2008. In this regard, about 23,21 and 20 farms in Mazandaran province, 30 farms in West and East Azerbaijan and Kurdistan provinces and 19 farms in Gilan and Ardebil were selected as randomly and tracking were done yearly from 2006-2008. This research was conducted according to regular planning consists of farms visit that was done according to statistical plan and completion of Questionnaires and sampling. The findings in Mazandaran province revealed that fish infections background and infectious diseases were increased in period of 2006-2008. In fact, 56% of all fish farms in 2006, 71% in 2007 and 85% in 2008 were recorded as infected farms. In other side, average weight of fish final products was more 500gr in consume market. So, regarding to long period of fish culture in mentioned fish occurrence of more morbidity could be expected. The streptococcus infections were most important fish bacterial diseases that have more incidence and pathogenicity in collected questionnaires. Also it revealed more occurrences in summer season in above 15oC temperature in affected fish farms. Also, Enteric Redmouth Disease (ERM) and Saprolegniasis were reported as second and third degree in examined farms. Meanwhile, findings of control, prevention and treatment of our survey revealed that using of antibiotics and detergent materials were increased in mentioned province. Indeed, 34.7% of all fish farms in 2006, 71.4% in 2007 and 75% in 2008 have applied treatment operation and using of detergent materials in affected farms. In other side, frequent using of Erythromycin antibiotic was reported several times in 2008 so fish farmer faced to Bacterial resistance and should be using from Florfenicol as alternative antibacterial. Also, in feed sampling from all fish farms about 3 fish farms in 2006 and 5 fish farms in 2008 were faced with food poisoning that originated from high TVN and peroxidase in fish food consumed. These farms revealed mass mortality that stopped after change feeding regime. In conclusion absence of fish health management could be considered as main agent of mentioned mortality in Mazandaran province. The findings of our survey in West and East Azerbaijan and Kurdistan revealed that absence of sufficient experiences in fish farmers and their neglect from water quality concepts, farm cleanness, using of suitable detergent materials for fish ponds and instruments and disability in continuous monitoring of physic-chemical factors of consumed water could be considered as most important problems. So, fish morbidity and mortality, growth decrement and low production rate were expected. Unfortunately, despite the occurrence of infectious and non- infectious diseases in examined fish farms, there were no documents and information about diseases history, clinical signs in dead fish, feeding regime, fish mortality (rate of daily mortality, age and weight of moribund fish), treatment operation, drugs usage, growth rate, physico-chemical factors and fish density. So planning for control and prevention of mentioned diseases were unsuccessful in affected fish farms. Also, occurrence of some epizootic fish viral diseases such as VHS, IPN and IHN were observed frequently with mass mortality about 40100% in some examined fish farms that produced some tragic economic lost in the mentioned provinces. Similarly, some bacterial, fungal and parasitic diseases were observed repeatedly in some inspected farms such as Flavobacterium, streptococcus infections. Also, some unknown causative agents in parasitic diseases were observed several times such as Dactylogyrus, Gyrodactylus, Ichthyophthirius multifiliis, Trichodina, Chilodonella, Diplostomum and fungal diseases such as Saprolegniasis. In conclusion it seems that absence of fish health management, inadequate rate of hygienic technical services, absence of quarantine programs for transfer of new eyed-eggs, juvenile and live broodstocks packages without health certificates from authorized organizations, uncontrolled entry of foreign eyed-eggs (France, Denmark, Australia and Armenia) and neglect in using of suitable detergent materials for fish ponds, instruments, consumed water and infected eggs, not screening of broodstocks in hatcheries could be considered as most important causative agents in occurrence of infectious diseases and main problems in affected farms in mentioned provinces. Similarly, our findings in Gilan and Ardebil provinces revealed that their problems were similar to other provinces. In fact, neglect in establish of necessary Infrastructures in fish farms and dereliction in health management concepts could be considered as main reasons of occurrence of fish infectious and non-infectious diseases in studied fish farms in mentioned provinces. In fact, often fish farms visited hadn't suitable structures without control and prevention approach. There were not observed detergent using, quarantine programs and prevention methods. Entrance of unknown persons, birds and wild animals were ordinary in mentioned farms. Unfortunately level of farmer’s knowledge was low and no training courses and extension programs were planned by authorized organizations. Meanwhile, food storages were unsuitable and food packages were stored in inappropriate situation so poisoning conditions were increased in examined farms. In conclusion it could be finalized that Coldwater fish farms in Gilan and Ardebil provinces situated in insufficient position and correction of current situation are needed urgently. In final elicitation, it would be mentioned that lack of basic infrastructures could be introduced as most important reasonfor spread of diseases, mortality and related economic losses in studied provinces. Therefore, attention to environmental affairs and access to Sustainable Development are recommended. Also consideration of biosecurity regulations and health management concepts would be important requirements for modification and reformation of Coldwater fish farms in examined provinces towards A Better Tomorrow

    Thigh-length compression stockings and DVT after stroke

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    Controversy exists as to whether neoadjuvant chemotherapy improves survival in patients with invasive bladder cancer, despite randomised controlled trials of more than 3000 patients. We undertook a systematic review and meta-analysis to assess the effect of such treatment on survival in patients with this disease

    Dynamics of the flowfield generated by the interaction of twin inclined jets of variable temperatures with an oncoming crossflow

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    International audienceThe present paper examines the common configuration of ``twin inclined jets in crossflow'' that is widely present in several industrial and academic, small and large-scale applications. It is particularly found in aerodynamic and engineering applications like VTOL aircrafts, the combustion mixing process and other chemical chambers. It can also be found in some domestic applications like chimney stacks or water discharge piping systems in rivers and seas. The twin jets considered in this work are elliptic as inclined with a 60A degrees angle and arranged inline with the oncoming crossflow according to a jet spacing of three diameters. They are examined experimentally in a wind tunnel. The corresponding data is tracked by means of the particle image velocimetry technique in order to obtain the different instantaneous and mean dynamic features (different velocity components, vortices, etc.). The same case is numerically reproduced by the resolution of the Navier-Stokes equations by means of the finite volume method together with the Reynolds stress model second order turbulent closure model. A non-uniform mesh system tightened close to the emitting nozzles is also adopted. The comparison of the measured and calculated data gave a satisfying agreement. Further assumptions are adopted later in order to improve the examined configuration: a non-reactive fume is injected within the discharged jets and the jets' temperature is varied with reference to a constant mainstream temperature. Our aim is to evaluate precisely the impact of this temperature difference on the flow field, particularly on the dynamics of the jets in a crossflow. This parameter, namely the temperature difference, proved mainly to accelerate the discharged jet plumes in the direction of the main flow, which enhanced the mixing, particularly in the longitudinal direction. The mixing in the other directions was also increased due to the weaker density of the jets, which enabled them to progress relatively unhindered before undergoing the impact of the crossflow

    TDP-43 gains function due to perturbed autoregulation in a Tardbp knock-in mouse model of ALS-FTD.

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    Amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD) constitutes a devastating disease spectrum characterized by 43-kDa TAR DNA-binding protein (TDP-43) pathology. Understanding how TDP-43 contributes to neurodegeneration will help direct therapeutic efforts. Here we have created a TDP-43 knock-in mouse with a human-equivalent mutation in the endogenous mouse Tardbp gene. TDP-43Q331K mice demonstrate cognitive dysfunction and a paucity of parvalbumin interneurons. Critically, TDP-43 autoregulation is perturbed, leading to a gain of TDP-43 function and altered splicing of Mapt, another pivotal dementia-associated gene. Furthermore, a new approach to stratify transcriptomic data by phenotype in differentially affected mutant mice revealed 471 changes linked with improved behavior. These changes included downregulation of two known modifiers of neurodegeneration, Atxn2 and Arid4a, and upregulation of myelination and translation genes. With one base change in murine Tardbp, this study identifies TDP-43 misregulation as a pathogenic mechanism that may underpin ALS-FTD and exploits phenotypic heterogeneity to yield candidate suppressors of neurodegenerative disease
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