Short communication: Study on heavy metals (Chromium, Cadmium, Cobalt and Lead) concentration in three pelagic species of kilka (Genus Clupeonella) in the southern Caspian Sea

Environmental pollution by heavy metals has been a matter of growing concern over the last decades. Heavy metals are toxic and tend to accumulate in living organisms. In many studies, fish has been used as a sampling item to monitor the quality of ecosystems because of two reasons: 1- Fish bio-concentrate and integrate contaminant load both in time and space leading to more representative results compared to water samples, and 2- Fish represent the bio-available fraction of environmental contaminants, unlike water and sediment samples. On the other hand, humans consume fish species which makes attention to these fauna even more important. Levels of some metals in the water running in Volga River, towards the Caspian Sea, and elevated concentrations of some trace elements have been reported in sediment. Also, various pollutants have accumulated in the Caspian Sea due to effluents from coastal catchments and leakage from offshore oil production and land-based sources. ... The objective of the present study was to investigate the concentrations of chromium (Cr), cadmium (Cd), cobalt (Co) and lead (Pb) in fish muscle in the most commercially important fish species of kilka (common kilka, C. cultriventris, anchovy C. engrauliformis and bigeye kilka C. grimmi) in the Caspian Sea

Extracting Topics from Open Educational Resources

In recent years, Open Educational Resources (OERs) were earmarked as critical when mitigating the increasing need for education globally. Obviously, OERs have high-potential to satisfy learners in many different circumstances, as they are available in a wide range of contexts. However, the low-quality of OER metadata, in general, is one of the main reasons behind the lack of personalised services such as search and recommendation. As a result, the applicability of OERs remains limited. Nevertheless, OER metadata about covered topics (subjects) is essentially required by learners to build effective learning pathways towards their individual learning objectives. Therefore, in this paper, we report on a work in progress project proposing an OER topic extraction approach, applying text mining techniques, to generate high-quality OER metadata about topic distribution. This is done by: 1) collecting 123 lectures from Coursera and Khan Academy in the area of data science related skills, 2) applying Latent Dirichlet Allocation (LDA) on the collected resources in order to extract existing topics related to these skills, and 3) defining topic distributions covered by a particular OER. To evaluate our model, we used the data-set of educational resources from Youtube, and compared our topic distribution results with their manually defined target topics with the help of 3 experts in the area of data science. As a result, our model extracted topics with 79% of F1-score.Comment: Editted version of this paper has been accepted to be published in the proceedings of The European Conference on Technology-Enhanced Learning (EC-TEL) 2020 by Springer (Lecture Notes in Computer Science (LNCS) Series

The use of modified atmosphere packaging for improvement shelf life of fresh Oncorhynchus mykiss

In this study, influence of modified atmosphere packaging on shelf life of trout (Oncorhynchus mykiss) (whole fish without visceral and without head and tail fish) stored in 4 to 6ºc was examined. Fish stored in MAP condition and control samples, in different time, were tested for spoilage chemical factors (TVN, PV and pH), microbial parameters (total viable count, clostridium botulinum) and sensory factors too. Mixed gases including co2 (30-50%), N2 (40-65%) and o2 (0 to 20%) were used for trout (without head and tail =6 treatments) and (whole fish without visceral and control = 2 treatments) statistical the analysis results showed that examined factors were significant difference during storage (P<0.001). Mixed gases haven t had inhibitory effect on spoilage factors (chemical and microbial parameters). However spoilage process was delayed. Increasing of chemical and microbial changes in control samples was higher than treatment samples especially TVN. The results also showed that shelf life of control samples stored 4-6ºc were between 6-12 days but in MAP samples were 19 days. Mixed gases including CO2 (40%), N2 (55%) and O2 (5%) were the best formula and the shelf life of fish (without head and tail) was 16 days where it was 19 days in whole fish (Lack of visceral). The results showed that storage of trout in MAP condition facilities storage and increasing of fish shelf life too

Creation of cryopreservation bank of bony fish

In this study, 11 male of Caspian trout (Salmo truta caspius) (with mean length and weight 37/8 ± 5/3 cm and 523/3 ± 24/7 respectively) and 23 male of Caspian kutum (Rutilus frisii kutum) (with mean length and weight 36/1 ± 7/1 cm and 631/3 ± 21/6 g respectively) were evaluated. All the fish were good at the initial examination of sexual maturity. After sperm sampling, their quality were tested. In this step, the parameters such as motility, duration of mobility, density, pH and osmolality were measured. After this stage, the sperm samples of Caspian trout in the ratio 1: 3 were diluted with the aqueous solution containing compounds (0.3M Glucose, 10% Methanol, 10% egg yolk) and the freezing process was done manually and the sperm was frozen in liquid nitrogen. The sperm samples of Caspian kutums were diluted (ratio of 1: 3) with two soluble diluent containing compounds (350 mM glucose, 30 mM Tris and 4% Polyethylene glycol) and (350 mM glucose, 30 mM Tris and 2% Glycerol) and were frizzed automatically by Planner Kryo instrument and placed in liquid nitrogen. The sperm samples were thawed 1 to 3 months after the date of first freezing and their quality were assessed by measuring percent and timing motility. The results showed that the obtained semen volume of Caspian trout was more than Caspian kutum. Moreover, percentage of motile sperm, timing motility and sperm density of Caspian trout were higher than those of Caspian kutum but osmolality and pH of Caspian trout were lower than those of Caspian kutum. Over time, the percentage of sperm motility and mobility for both species declined compared with fresh samples. After thawing, percentage of motile sperm and timing motility of Caspian kutum were lower than those factors Caspian trout. The results showed that the sample of Caspian kutum sperm that were diluted by ethylene glycol after thawing and were immotile ll of them. However, the samples were diluted by glycerol, after thawing, were alive and motile. According to the results, it seems very important species differences that must be fully considered in the process of freezing sperm. The use of a single protocol would not be successful in cryopreservation because the reaction of sperm against to chemical agents is variable. Therefore, it is essential to get the right information to protect valuable Caspian fish by using cryopreservation. Further studies on the characteristics of each species, as well as the freezing process take appropriate diluent

Stock assessment of the bony fishes in Iranian coastal waters of the Caspian Sea (2005-2007)

Exploitation of bony fishes resources started on 12 October 2005 and finished on 9 April 2006 in 2005-2006. 142 beach seines caught about 14333.4 tons of bony fishes by 47101 hauling. The total catch was estimated 21844.7 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 97 percent of total catch. Length classes 39-40, 31-32 and 40-41 cm predominated for kutum, golden grey mullet and common carp, respectively. Age groups 3 to 5 year comprised 84.2, 74.8 and 83.7 percent for Kutum, golden grey mullet and common carp, respectively and age group 4 year was dominant with 42.0, 35.9 and 43.0 percent, respectively. K value and L_∞ calculated 0.26 (/year) and 58.3 cm for Kutum and 0.15 (/year) and 61.5 cm for golden grey mullet, respectively. The total biomass and MSY estimated about 24733.7 and 8550.4 tones for kutum and about 16948.0 and 4999.0 tones for golden grey mullet, respectively. Exploitation rate (E) calculated 0.71 and 0.70 for Kutum and golden grey mullet, respectively. In 2006-2007, the exploitation of bony fishes resources started on 12 October 2006 and finished on 7 April 2007 in 2006-2007. 134 beach seines caught about 14120.0 tons of bony fishes by 48470 hauling. The total catch was estimated 23801.8 tones (Includes illegal fishery). Kutum, mullets and common carp comprised more than 98.5 percent of total catch. Length classes 39-40 and 38-39 cm predominated for kutum and common carp, respectively and length classes 27-28 and 29-30 cm predominated for golden grey mullet. Age groups 3 to 5 year comprised 80.2 and 71.8 percent for kutum and golden grey mullet, respectively and age groups 4 to 6 year comprised 71.8 percent for common carp. Age group 3, 4 and 5 year was dominant with 35.5, 32.1 and 27.1 percent for kutum, golden grey mullet and common carp respectively. K value and L∞ calculated 0.27 (/year) and 60.7 cm for Kutum, 0.2 (/year) and 58.4 cm for golden grey mullet and 0.19 (/year) and 66.7 cm for common carp, respectively. The total biomass and MSY estimated about 46654.9 and 14801.4 tones for Kutum, about 19549.0 and 5748.4 tones for golden grey mullet and about 10584.3 and 2186.0 tones for common carp, respectively. Exploitation rate (E) calculated 0.69, 0.53 and 0.52 for kutum, golden grey mullet and common carp, respectively

Trace metal distribution in the bed, bank and suspended sediment of the Ravensbourne River and its implication for sediment monitoring in an urban river

Purpose This study aims to identify a suitable sediment compartment for sediment quality monitoring by: (a) studying the concentration of trace metals (Cd, Cu, Ni, Pb and Zn) in the bed, bank and suspended sediment compartments of the Ravensbourne River to establish any differences in trace metal concentrations with compartment; (b) determining the influence of sediment particle size fractions ( 0.05) in the concentrations of metals between the suspended sediment and the < 63 μm bed sediment fraction, but there was a significant difference (p < 0.05) between the suspended sediment and the < 63 μm bank sediment fraction. There were also significant differences between the concentrations of metals in the < 63 μm and the 63 μm–2 mm fractions. Generally, the Ravensbourne River did not comply with the draft UK sediment quality guidelines for the metals analysed. Conclusions This study shows the importance of identifying a suitable sediment compartment to sample for compliance with sediment quality standards. The bed and suspended sediments are the most widely used sediment compartments for sediment monitoring, but collecting sufficient mass of the < 63 μm sediment fraction for monitoring presents a challenge for urban gravel bed rivers like the Ravensbourne River. It seems appropriate to establish individual monitoring regimes for different rivers

Effect of Aegle Marmelos Fruit Juice Concentrate on Serum Glucose and Lipid Level and ALT/AST Activities in Diabetic Rats

Abstract: Introduction: This study was carried out to investigate the effect of bael (Aegle marmelos) on glucose, cholesterol, triglyceride, creatinine levels and the activity of ALT and AST in the serum of diabetic rats. Method: 45 Adult male Sprague Dawley rats were selected. The rats were divided into three groups. The first group was considered as negative control (non-diabetic rats) and diabetes mellitus was induced in the remained rats by I.V. injection of alloxan (50 mg/kg BW). Following induction of diabetes mellitus 15 diabetic rats were considered as positive control and 15 ones as treatment group. Treatment group was fed with homogenous mixture of ordinary rat food and Bael concentrate (2gr/kg food)for three weeks and the remaining groups were fed with ordinary rat food. Results: Following induction of diabetes mellitus, concentration of serum glucose, cholesterol, triglyceride and the activity of ALT increased significantly (P<0.01), but AST activity and creatinine concentration not varied. Food and water intake was increased and body weight of rats was decreased (p<0.01). Consumption of bael concentrate caused a significant decrease in serum glucose, cholesterol, triglyceride and the activity of ALT (P<0.01), and also food and water intake was decreased (p<0.01). Conclusion: The results of this study show that Aegle marmelos concentrate exhibit hypoglycemic and hypolipidaemic effects in diabetic rats. Keywords: Aegle marmelos, Gucose, Lipid, ALT, AST, Diabetes mellitus, Ra

Assessment of RIP-V1 and OSPF-V2 protocol with consideration of convergence criteria and sending protocols traffic

Routing Protocols are underlying principles in networks like internet, transport and mobile. Routing Protocols include a series of rules and algorithms that consider routing metric and select the best way for sending healthy data packets from origin to destination. Dynamic routing protocol compatible to topology has a changeable state. RIP and OSPF are dynamic routing protocol that we consider criteria like convergence and sending protocols traffic assessment RIP first version and OSPF second version. By the test we have done on OPNET stimulation we understood that the OSPF protocol was more efficient than RIP protocol

With using fuzzy logic in the MANET

Mobile ad hoc networks have consisted of the nodes which are freely displaced. In other words, this network has dynamic topology. Routing protocols find route of forwarding data packets from the source node to the destination node. A routing protocol plays important role in finding the shortest time and the route path. In this paper, considering significance of the subject, attempt has been made to present a model using fuzzy logic approach to evaluate and compare two routing protocols i.e. AODV DSDV using effective factor of the number of nodes based on 2 outputs of delay and throughput rate (totally fuzzy system with four outputs) in order to select one of these two routing protocols properly under different conditions and based on need and goal. To show efficiency and truth of fuzzy system, two protocols have been evaluated completely equally using NS-2 simulator and attempt has been made to prove efficiency of the designed fuzzy system by comparing results of simulation of fuzzy system and NS-2 software