• Journal of Embryo Transfer
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• v.17 no.3
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• pp.203-209
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• 2002

The aim of this study was to assess the developmental capacity of oocytes maturated in vitro after 10 days of culture when the preantral follicles were isolated from juvenile mice 10- and 20-day old, respectively, and to develop in vitro culture system that observed a view to morphology of follicles and nucleus maturation of oocytes. The antral-like cavities became formation after 6 days of culture in follicle isolated from 10- and 20-day old mice. The number of follicles were 21.5 and 33.3 in ovary isolated from 10- and 20-day old mice, respectively. The diameters of oocytes were 51.85 and 57.50 ${\mu}{\textrm}{m}$ before culture and were grew 55.95 and 63.11 ${\mu}{\textrm}{m}$ after culture for 10 days, in follicles isolated from 10- and 20-day old mice, respectively. The observation rates up to the M II and from GV to M II were 4.3 and 22.1%, and 14.5 and 61.1% after culture for 10 days in follicles isolated from 10- and 20-day old mice, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.257-261
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• 2009

Two feeding trials were conducted to investigate the effects of several dietary additives on growth and feed utilization of juvenile flounder. In the first experiment, three replicate groups of juveniles (average weight 1.5 g) were fed diets with or without wasabi extract and chitosan for 7 weeks. Survival rate, weight gain, protein efficiency ratio, hepatosomatic index and condition factor were not affected by the different dietary additives (P>0.05). Feed efficiency of fish fed the wasabi extract diet was significantly higher than that of fish fed the control diet (P<0.05). Daily feed intake of fish fed the wasabi extract diet was significantly lower than that of fish fed the other diets (P<0.05). In the second experiment, three replicate groups of juveniles (average weight 1.4 g) were fed diets with or without Pophyra powder for 7 weeks. Survival rate and weight gain were not significantly affected by dietary Pophyra powder (P>0.05). Feed efficiency and protein efficiency ratio of fish fed the Pophyra diet were significantly lower than those of fish fed the control diet (P<0.05). The results of these experiments suggest that feed efficiency of juvenile flounder may be improved by dietary supplementation with wasabi extract.

• Convergence Security Journal
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• v.15 no.6_2
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• pp.37-44
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• 2015

There appears a variety forms of crime type and age in accordance with the change of social structure. In this paper it is described for combining the Anomie theory of Emile Durkheim. Anomie refers to the absence of dual standards or norms. In other words, while weakening the existing norms prevailing when the new rules has not been established. That situation would cause social chaos. Rules on the dissemination and utilization of SNS due to the development of information and communication technology undermine the social norms while online regulations are being a weak state not established. In the confusion of these norms it has been shown to increase in juvenile delinquency. Social media has characteristics such as openness, accessibility, relationships, and content diversity. The social media itself is not subject to the general mechanisms of consumption and production due to growing as a kind of organism. It has characteristic to make the most content by utilizing the users to voluntarily share information. Social media using as communication, contact and information in the youth, thus the possibility of crime is high. Social media is also direct and indirect influence on youth crime but no apparent systemic regulation of this situation.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.51-56
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• 2015

A 8-week trial was conducted to evaluate the effects of photoperiod manipulation on the growth performance and hematological parameters of juvenile Caspian roach, Rutilus rutilus caspicus (average weight $1.46{\pm}0.12g$ mean${\pm}$SD) reared under five photoperiods (24 h Light, 24L; 18 h Light & 6 h Dark, 18L:6D; 12 h Light & 12 h Dark, 12L:12D; 6 h Light & 18 h Dark, 6L:18D; 24 h Dark, 24D) with constant light intensity 1,500 lx on the water surface. Triplicate of 20 fish were allocated into each of 15 fiberglass tanks of 50 L capacity and they were fed three times per day with the commercial feed (SFK, Co., Sari - Iran) contains 50.0% protein and 10.5% lipid. At the end of experimental period, final body weight, weight gain and specific growth rates of fish exposed to 24L were significantly higher than those of fish exposed to 12L:12D, 6L:18D and 24D (P < 0.05). Red blood cell and hemoglobin of fish exposed to 24L were significantly higher than those of fish exposed to 24D. No significant difference observed in hematocrit, white blood cell and plasma glucose among the different treatments groups. Therefore, these results demonstrated that the growth performance of juvenile Caspian roach can be significantly stimulated by using 24L and 18L:6D photoperiods without any measurable significant stress response such as plasma glucose concentration.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.45-50
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• 2015

A 10-day trial was conducted to evaluate the salinity tolerance and hematological responses of juvenile ship sturgeon Acipenser nudiventris under different salinity levels. A total of 240 fish averaging $6.2{\pm}0.13g$ (mean${\pm}$SD) were randomly distributed into 12 tanks in groups of 20, and each tank was then randomly assigned to one of three replicates of four different salinities at 0, 4, 8 and 12‰. At the end of 10 days of experimental period, plasma protein value of fish exposed to 0‰ and 4‰ salinities was significantly higher than those of fish exposed to 8‰ and 12‰ salinities (P < 0.05). Significantly higher values for plasma cortisol and glucose were obtained in fish exposed to 12‰ salinity compared to the fish exposed to 0‰ and 4‰ salinities (P < 0.05). Plasma potassium and sodium values increased significantly by increment of salinity levels (P < 0.05). Therefore, these results indicated that in natural environments, juvenile ship sturgeon, A. nudiventris in migratory populations could be able to migrate and adjust successfully into brackish water with a salinity of up to 8‰ without any short-term hematological stress responses.

• Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.350-353
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• 2009

As a result of human industrial development, carbon dioxide ($CO_2$) is currently accumulating in the atmosphere and dissolving into the oceans. Sequestration into the deep sea has been proposed as a possible solution to this increasing atmospheric $CO_2$, although the impact of such a program on marine ecosystems is unknown. We examined the effects of increased $CO_2$ levels on the growth of the olive flounder, Paralichthys olivaceus. Juvenile olive flounder 40 days post hatching were exposed to two levels of $CO_2$ (3.60-7.55 and 4.05-11.46 kPa) in running seawater for 26 days. During the exposure period, the pH and $CO_2$ levels of the water were measured, and the numbers of dead individuals were counted in each aquarium. Following the exposure period, the total lengths (mm) and body weights (mg) of the juvenile fish were measured. Both $CO_2$ treatments significantly increased fish mortality compared to controls ($19.87\pm4.53%$ vs. 7.14% and $75.96\pm1.36%$ vs. 7.14% for high and low doses, respectively). After the high $CO_2$ treatment, total length ($14.98\pm6.58$ mm vs. $19.52\pm1.83$ mm) and body weight ($28.92\pm13.85$ mg vs. $67.35\pm18.32$ mg) of the exposed flounder were reduced compared to the control fish; however, no significant differences in these values were observed after the low $CO_2$ dose. These results suggested that $CO_2$ exposure inhibits growth in the juvenile stage and that $CO_2$-enriched seawater is toxic in the early life stages of olive flounder.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.477-484
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• 2016

There is renewed interest in natural products as a starting point for discovery of drugs for schistosomiasis. Recent studies have shown that phytol reveals interesting in vivo and in vitro antischistosomal properties against Schistosoma mansoni adult worms. Here, we report the in vitro antischistosomal activity of phytol against Schistosoma haematobium juvenile and adult worms and alterations on the tegumental surface of the worms by means of scanning electron microscopy. The assay, which was carried out with 6 concentrations (25, 50, 75, 100, 125, and $150{\mu}g/ml$) of phytol, has shown a promising activity in a dose and time-dependent manner. There was a significant decline in the motility of the worms and a mortality rate of 100% was found at 48 hr after they had been exposed to phytol in the concentration of $150{\mu}g/ml$. Male worms were more susceptible. On the ultrastructural level, phytol also induced tegumental peeling, disintegration of tubercles and spines in addition to morphological disfiguring of the oral and ventral suckers. This report provides the first evidence that phytol is able to kill S. haematobium of different ages, and emphasizes that it is a promising natural product that could be used for development of a new schistosomicidal agent.

• Development and Reproduction
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• v.18 no.3
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• pp.127-131
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• 2014

We investigated the androgenic effects of $17{\alpha}$-methyltestosterone (MT) on gonadal sex reversal in juvenile red spotted grouper Epinephelus akaara. The fish were immersed in $17{\alpha}$-MT at 1 and 5 mg/L. Treatment method of $17{\alpha}$-MT was once weekly for 4 and 8 weeks. Fish were sampled at 12 months after end of the treatment period in order to histological analysis. At the initiation of an experiment (70 day after hatching), juvenile red spotted grouper have the paired primordial gonads with somatic cells bellow kidney in the posterior portion of the body cavity. Formation of ovarian cavity indicates that the ovarian differentiation beginning at 70 DAH in red spotted grouper. At 12 months after end of the treatment period, control group, $17{\alpha}$-MT 1 mg/L treatment group for 4 and 8 weeks, and $17{\alpha}$-MT 5 mg/L treatment group for 4 weeks were all female. However, sex-changed males without ovarian cavity were observed in the $17{\alpha}$-MT 5 mg/L treatment group for 8 weeks. In grouper, we firstly reported that the red spotted grouper be able to induce the primary males by hormone treatment prior to gonadal sex differentiation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.3
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• pp.329-336
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• 2015

We examined the effect of substituting squid meal and macroalgae with soybean meal in a commercial diet on the growth and body composition of juvenile abalone Haliotis discus hannai. We randomly distributed 2310 juvenile abalone into 33 rectangular plastic containers and fed them five experimental diets in triplicate as follows. The control diet (Con) consisted of 12% squid meal, 8% corn gluten and 20% soybean meal as protein source, wherein 10% ${\alpha}$-starch, 20% wheat flour, and 5% dextrin were carbohydrate source. The experimental diets, 50% squid meal (SM50), 50% squid meal and 50% macroalgae (SM50+MA50), and 100% squid meal and 50% macroalgae (SM100+MA50) were substituted with the same respective amounts of soybean meal. The fifth experimental diet consisted of the control diet plus 1% diatom powder (DP). We prepared two domestic (Domestic A and B) and two imported (China and Japan) abalone feeds. Finally, we prepared Undaria and sea tangle. We found that the weight gain of abalone fed the Con, DP, and China and Japan diets was significantly greater than that of abalone fed Undaria and sea tangle. We conclude that the substituting squid meal and macroalgae with soybean meal in abalone feed has limited benefits, but supplementing diets with 1% diatom powder is effective in improving weight gain.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.180-186
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• 1998

A 10-week feeding experiment was conducted to determine the phosphorus requirement of juvenile Korean rockfish (Sebastes schlegeli). Three replicate groups of fish initially averaging 4.2g were fed the semipurified experimental diets containing graded levels of $NaH_2PO_4\;\cdot\;2H_2O$ to provide from $0.1\%$ to $1.32\%$ total phosphorus level in a flow-through seawater system. Korean rockfish muscle and casein were used as the protein sources of the basal diet. Weight gain, feed efficiency and protein retention of fish fed the $0.35\%$ phosphorus were higher than those of fish fed the $0.1\%$ phosphorus, although no significant improvements $(P>0.01)$ were observed above the level. Determined phosphorus requirement using the broken line model was found to be $0.3\%$ for weight gain. Moisture, protein and lipid contents of whole body and muscle were not affected by dietary phosphorus levels $(P>0.01)$. Lipid contents of liver in fish fed the $0.1\%$ phosphorus were lower than those in fish fed the $0.35\%$ and $1.32\%$ phosphorus $(P<0.01)$. Dietary phosphorus increased ash and phosphorus contents of the whole body, while those of bone were not affected $(P>0.01)$. The data obtained in this study indicate that a $0.3\%$ dietaryphosphorus level could be recommended for the optimum growth and efficient nutrient utilization of juvenile Korean rockfish.