• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.1
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• pp.50-55
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• 2003

In order to study on the improvement of gill nets and trap nets fishing for the management of fisheries resource in the coastal area of Yellow Sea, we have investigated the general present condition of those fishing, and the actual fishing operation of gill nets for croaker and trap nets for rock shell which is called the the other trap nets, and then measured the body length of croaker and blue shell caught by their fishing vessels. The results are as follows ; 1. The total number of permission for coastal fishing are 12,944 cases, but the number of operation for coastal fishing are 7,558 cases in the coastal area of Yellow Sea. Among the total number of permission, the gill nets fishing are 5,154 cases with 39.8% but even so the number of operation are 3,724 cases, the trap nets fishing are 1,025 cases with 7.6% but even so the number of operation are 662 cases. On the fishing ratio, the gill nets and trap nets fishing are comparatively higher than the other fishing with 72.3% and 64.6%, respectively. 2. The main fishing period of gill nets for croaker is from the middle of July to early of September, and the main fishing grounds are sandymud bottom of 15-50m in depth around the islands of southern parts of western coastal area, and the fishing operation carry out 1∼2 times per day in flood tide and nets hauling conduct in 1∼2 hours after drifting with current. 3. The distribution range of body length of 139 croakers, which are caught in the gill nets, are 43.0∼120.0㎝ and the mode is 85.0㎝. 4. The main fishing period of trap nets for rock shell which is called the other trap nets is all the year round except the catching period of blue crab from early of September to the middle of October, and the main fishing ground are the sandymud bottom of 10∼20m in depth, and nets hauling conduct in next day after nets casting. 5. The distribution range of maximum carapace of 5,372 rock shells are 4.5∼8.5㎝ and the mode is 7.5㎝.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.1
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• pp.56-62
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• 2003

To investigate the entrapping behavior of blue crab, rock shell and green ling, which are mainly caught with the other trap nets in the coastal area of Yellow Sea, by the using duration of trap nets through the water tank experiment. We select the three kinds of trap nets which have different using duration such as new, 6 months and 12 months used one, and observe the entrapping ratio into the trap nets, respectively. In the mean while, in order to obtain the basic data for the estimate of mesh selectivity of the other trap nets, the entrapping behavior into the trap nets for green ling which has high activity compared to blue crab and rock shell, are examined to the three kinds of mesh size (35mm, 50mm and 65mm). The results are as follows ; 1. The mean entrapping ratio of blue crab by the using duration of trap nets in high with 4.4 fishes (44.0%) in the 6 months used one, become lower with 2.9 fishes (28.0%) in the new one, and with 2.0 fishes (20.0%) in the 12 months used one. 2. The mean entrapping ratio of rock shell by the using duration of trap nets in high with 7.3 fishes (36.7%) in the new one, and become lower with 7.2 fishes (35.8%) in the 6 months used one, and with 5.7 fishes (28.3%) in the 12 months used one. 3. The mean entrapping ratio of green ling by the using duration of trap nets in high with 3.4 fishes (34.0%) in the 6 months used one, and become lower with 3.0 fishes (30.0%) in the new one, and with 2.8 fishes (28.0%) in the 12 months used one. 4. The mean residual ratio of green ling by the mesh size of trap nets is high with 2.4 fishes (24.0%) in the 35mm mesh size, and become lower with 2.2 fishes (22.0%) in the 50mm mesh size and 2.0 fishes (20.0%) in the 65mm mesh size.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.176-181
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• 2004

In order to examine the mesh selectivity and optimum mesh size of trap nets for purple shell, Rapane venosa, the field experiments were carried out during Jun. 27 to 29, 2003 at the coastal area of Mal-Do, Kunsan, Jeonbuk province. The experimental fishing gears were used in two set of trap nets, which one set was consisted of 210 trap nets that were coverd with 35mm, 50mm and 65mm in mesh size. The analysis of mesh selectivity curve was done by Kitahara's method. The results obtained are summerized as follows : 1. The total number of catch by the experimental fishing of trap nets for purple shell was 1,682, and it was consisted of 1,268 purple shells (75.4%), 225 Glossaulax reiniana (13.4%), 113 green lings (6.7%) and 76 other fishes (4.5%). 2. The value of maximum 1/m on the mesh selectivity curve was estimated at 1.79. 3. The value of 1/m on the 50% selection range was estimated at 1.24${\sim}$2.72, and the selection width was 1.48.. 4. The optimum mesh size of trap nets for purple shell based on the catch prohibition shell height(50mm) was estimated 40.3mm, and the 50% selection range of shell height of purple shell was 50.0${\sim}$109.6mm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.2
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• pp.95-100
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• 2005

In order to improve the gill nets for croaker, Miichthys miiuy which is proper to the fishermen's income ans fisheries resource management, we had studied to the net height of present gill nets (mesh size 160mm, 50 mesh in depth), experimental gill nets-I(mesh size 150mm, 68 mesh in depth) and experimental gill nets-II(mesh size 142mm, 75 mesh in depth) in wter using the gill nets design ans analysis simulation system, and then investigated and analyzed the catch efficiency of each gill nets through the field fishing experiments. The net height of emperimental gill nets-I and experimental gill nets-II in water were estimated respectively about 1.5 times and 1.3 times higher than present gill nets which the net height is about 3.5m as the results of simulation considering the current of fishing fields. Total number of croakers which were caught by the persent gill nets was 62(body length 300~1,200mm), total catch weight was 398.7kg (mean 0.6kg/sheet). Total number of croakers which were caught by the experimental gill nets- I was 68(body length 600~1,100mm), total catch weight was 391.6kg (mean 1.2kg/sheet). Total number of croakers which were caught by the experimental gill nets-II was 28(body length 400~900mm), total catch weight was 99.2kg (mean 0.3kg/sheet).

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.212-214
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• 2001

Siphons and traps are special structures of Petri nets with closely related to liveness for the deadlock analysis of Discrete Event Dynamic Systems. It can analysis the liveness of Petri nets using the siphon and trap without to check reachability.[1] Deadlock analysis approach we proposed is based on the notion of potential deadlock which are siphons that eventually become empty. And in this paper, we proposed a initial marking method by siphon to avoid and to prevent deadlock. It is shown that our approach is more efficient than classical state enumeration approach.

• IMMUNE NETWORK
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• v.23 no.5
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• pp.38.1-38.14
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• 2023

Neutrophils are professional phagocytes that provide defense against invading pathogens through phagocytosis, degranulation, generation of ROS, and the formation of neutrophil extracellular traps (NETs). Although long been considered as short-lived effector cells with limited biosynthetic activity, recent studies have revealed that neutrophils actively communicate with other immune cells. Neutrophils employ various types of soluble mediators, including granules, cytokines, and chemokines, for crosstalk with immune cells. Additionally, ROS and NETs, major arsenals of neutrophils, are utilized for intercellular communication. Furthermore, extracellular vesicles play a crucial role as mediators of neutrophil crosstalk. In this review, we highlight the extracellular mechanisms of neutrophils and their roles in crosstalk with other cells.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.169-175
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• 2004

In order to examine the mesh selectivity and optimum mesh size of gill nets for croaker, Milichthys miiuy, the field experiments were carried out during Aug. 10 to 14, 2002 and Aug. 10 to 17, 2003 at the caostal area of Imja-Do, Shinan, Jeonnam province. The experimental fishing gears were used in two set of gill nets, which one set was consisted of 12 sheets of gill nets, and each set was connected alternatively 4 different sheets that were 129mm, 135mm, 144mm and 150mm in mesh size. The analysis of mesh selectivity curve was done by Kitahara's method. The results obtained are summerized as follows : 1. The total number of catch by the experimental fishing of gill nets for croaker was 719, and it was consisted of 526 croakers (73.1%), 168 blue crabs (23.4%), 17 harvest fishes (2.4%) and 8 other fishes (1.1%). 2. The value of maximum 1/m on the mesh selectivity curve was estimated at 6.91. 3. The value of 1/m on the 50% selection range was estimated at 5.62${\sim}$80.3, and the selection width was 2.41. 4. The optimum mesh size of gill nets for croaker was estimated 142mm, and the 50% selection range of total length of croaker was 798${\sim}$1,140mm.

• Parasites, Hosts and Diseases
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• v.47 no.2
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• pp.159-165
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• 2009

House-residual spraying and insecticide-treated bed nets have achieved some success in controlling anthropophilic and endophagic vectors. However, these methods have relatively low efficacy in Korea because Anopheles sinensis, the primary malaria vector, is highly zoophilic and exophilic. So, we focused our vector control efforts within livestock enclosures using ultraviolet black light traps as a mechanical control measure. We found that black light traps captured significantly more mosquitoes at 2 and 2.5 m above the ground (P<0.05). We also evaluated the effectiveness of trap spacing within the livestock enclosure. In general, traps spaced between 4 and 7m apart captured mosquitoes more efficiently than those spaced closer together (P>0.05). Based on these findings, we concluded that each black light trap in the livestock enclosures killed 7,586 female mosquitoes per trap per night during the peak mosquito season (July-August). In May-August 2003, additional concurrent field trials were conducted in Ganghwa county. We got 74.9% reduction (P<0.05) of An. sinensis in human dwellings and 61.5% reduction (P>0.05) in the livestock enclosures. The black light trap operation in the livestock enclosures proved to be an effective control method and should be incorporated into existing control strategies in developed countries.

• 한국해양학회지
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• v.15 no.2
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• pp.108-111
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• 1980

The sampling was made by a kind of trap nets and an electric fishing apparatus in the lagoons of Arcachon Bay. Length frequency distributions obtained by two gears are combined to propose more reliable length composition of the population. The biomass was estimated by the capture and recapture method in a limited area with electric fishing apparatus, and it was redressed based on the corrected length composition. It showed approximately 638kg/ha in the deeper parts of the lagoons. It suggests that the lagoons of Arcachon Bay contain relatively high density of eels.

• Journal of Veterinary Clinics
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• v.40 no.3
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• pp.175-181
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• 2023

Fucoidan extracted from brown seaweed has a variety of biological activities. Neutrophil extracellular traps (NETs) formation is an immune response for the invasion of pathogens. Neutrophils release granule protein and chromatin that form extracellular fibers that bind microbes. These NETs degrade virulence factors and kill bacteria. The aim of this study was to investigate the effect of fucoidan on NET formation of porcine peripheral blood polymorphonuclear cells (PMNs). The NET formation was determined by fluorescence emission of propidium iodide (PI) in PMNs by a fluorescence microplate reader. The production of tumor necrosis factor (TNF)-α from peripheral blood mononuclear cells (PBMCs) was measured by ELISA method. Fucoidan itself did not show any direct effect on NET formation. However, NET formation of PMNs was increased by the culture supernatant from PBMCs treated with fucoidan. The NET formation of PMNs were also enhanced by treatment with recombinant porcine (rp) TNF-α. The ability of culture supernatant from PBMCs treated with fucoidan to increase the NET formation of PMNs was inhibited by addition of goat anti-rp TNF-α polyclonal antibody (pAb) (IgG) prior to the culture. The increase of NET formation by rp TNF-α was also inhibited by goat anti-rp TNF-α pAb (IgG). The level of TNF-α in culture supernatant from PBMCs was increased by treatment with fucoidan. These results suggest that fucoidan increases porcine NET formation, which is mediated by TNF-α produced from PBMCs.