101 research outputs found
Catch performance of coastal squid jigging boats using LED panels in combination with metal halide lamps
Squid attracting light systems consisting of low power light emitting diode panels (LEDs) and conventional metal halide lamps (MHs) were tested to describe the influence of combinations of LEDs and MHs on squid catch. Fishing trials using LEDs (9. kW) and different numbers of MHs were carried out in August and September 2009 targeting two squid species: (1) Japanese common squid Todarodes pacificus in northern waters of the Sea of Japan (off Hokkaido) by 4 coastal squid jigging boats (19 gross tonnage) and (2) swordtip squid Photololigo edulis in western waters (off Iki) by 5 boats of the same class. Catches of both species tended to increase with the number of MHs. Generalized Linear Model analysis revealed that in addition to the number of MHs, the catch amount was influenced by fishing power (ability) of boat and by the monthly variation of squid abundance (only for P. edulis off Iki). The expected catch (number of boxes) was not proportional to the number of MHs. The largest catch was expected for P. edulis off Iki by using LEDs with 24 MHs. The optimal combination of LEDs and MHs for T. pacificus off Hokkaido was less clear because the combination with 36 MHs had the largest positive effect on the catch; this was the maximum number MHs used
Research and development strategy for fishery technology innovation for sustainable fishery resource management in north-east Asia
The development of fishery technologies supports food sustainability to achieve a steady supply of fish and fishery products. However, the priorities for research and development (R&D) in fishery technologies vary by region due to differences in fish resource availability, environmental concerns, and consumer preferences for fishery products. This study examines trends in fishery technology innovations using data on patents granted as an indicator of changing R&D priorities. To clarify changes in R&D priorities, we apply a decomposition analysis framework that classifies fishery technologies into three types: harvesting, aquaculture, and new products. This study mainly focuses on China, Japan, and Korea as the major fishing countries in the north-east Asia region. The results show that the number of fishery technology patents granted increased between 1993 and 2015; in particular, the number of aquaculture patents granted has grown rapidly since 2012. However, the trend in Japan was the opposite, as the apparent priority given to aquaculture technology innovation decreased between 1993 and 2015. The trends and priority changes for fishery technology inventions vary by country and technology group. This implies that an international policy framework for fishery technology development should recognize that R&D priorities need to reflect diverse characteristics across countries and the technologies employed
The effect of lunar cycle, tidal condition and wind direction on the catches and profitability of Japanese common squid Todarodes pacificus jigging and trap-net fishing
Jigging with artificial lights (squid jigging) and deploying of large scale trap-net (also known as a set-net in Japan), are the major methods to capture Japanese common squid Todarodes pacificus in western Japan. Squid jigging is a highly selective fishing method. However, it consumes large amount of energy for steaming to the fishing ground and for lighting. In contrast, trap-net fishing requires substantially less energy but its capture efficiency is strongly influenced by its stationary mode of capture. The primary objective of this study was to analyze how various environmental and biological factors such as the lunar cycle, tidal condition, wind direction and squid abundance affect the capture efficiency of squid jigging and trap-net fishing. We analyzed the effect of these factors on squid catch in five Fisheries Cooperative Associations located on four islands in Nagasaki Prefecture, western Japan. Our analysis shows that squid catch in jigging and trap-net fishing is mainly influenced by the lunar cycle but also tide and wind direction play a marked role. In addition, squid abundance significantly affects the catches in trap-net fishing. Recommendations are made to improve the overall profitability of squid fishing by proper choice of the capture method, location and season
ポップアップアーカイバルタグおよび超音波発信器で調べたエチゼンクラゲの遊泳深度
The swimming depths of 12 individual Nemopilema nomurai with bell diameters of 0.8-1.6 m were investigated using pop-up archival transmitting tags and ultrasonic pingers, and the validity of the research method was evaluated. The N. nomurai studied frequently showed vertical movement, with the swimming depth ranging from 0 to 176 m, The mean swimming depths of most individuals were less than 40 m. The swimming depths of N. nomurai in the northern Japan Sea in the winter were mostly deeper than those of this species in the southern Japan Sea in the autumn. This result suggests that the range of the depths almost depends on the vertical structure of the ocean. Swimming depths during the nighttime were significantly deeper than those during the daytime. More specifically, during the daytime, the swimming depths in the afternoon tended to be shallower than those in the morning, while during the nighttime, the swimming depths after midnight were deeper than those before midnight.エチゼンクラゲ計12個体の遊泳深度をポップアップタグや超音波発信器により調べるとともに,調査手法の妥当性を確認した。エチゼンクラゲは活発な鉛直移動を繰り返していた。遊泳深度は0~176m の範囲で,ほとんどの個体の平均遊泳深度は40m より浅かった。遊泳深度は秋の日本海南部よりも冬の日本海北部の方が深くなる傾向があり,基本的に滞在深度範囲は海洋の鉛直構造に依存していると推測された。遊泳深度は日中よりも夜間の方が深かった。日中には午前より午後の方が浅く,夜間には前半夜よりも後半夜の方が深くなる日周性が確認された
Secreted Ectodomain of SIGLEC-9 and MCP-1 Synergistically Improve Acute Liver Failure in Rats by Altering Macrophage Polarity
Effective treatments for acute liver failure (ALF) are still lacking. We recently reported that a single intravenous administration of serum-free conditioned medium from stem cells derived from human exfoliated deciduous teeth (SHED-CM) into the D-galactosamine (D-Gal)-induced rat ALF model improves the liver injury. However, the specific factors in SHED-CM that are responsible for resolving ALF remain unclear. Here we found that depleting SHED-CM of two anti-inflammatory M2 macrophage inducers—monocyte chemoattractant protein-1 (MCP-1) and the secreted ectodomain of sialic acidbinding Ig-like lectin-9 (sSiglec-9)—abolished its ability to resolve rat ALF. Furthermore, treatment with MCP-1/sSiglec-9 alone dramatically improved the survival of ALF rats. This treatment induced anti-inflammatory M2, suppressed hepatocyte apoptosis, and promoted hepatocyte proliferation. Treatment with an M2-depletion reagent (mannosylated clodronate liposomes) suppressed the recovery. In addition, MCP-1 and sSiglec-9 synergistically promoted the M2 differentiation of bone marrow-derived macrophages via CCR2, accompanied by the production of multiple liver-regenerating factors. The conditioned medium from MCP-1/sSiglec-9-activated M2 macrophages, but not from interleukin-4-induced ones, suppressed the D-Gal- and LPS-induced apoptosis of primary hepatocytes and promoted their proliferation in vitro. The unique combination of MCP-1/sSiglec-9 ameliorates rat ALF by inhibiting hepatocellular apoptosis and promoting liver regeneration through the induction of anti-inflammatory/tissue-repairing M2 macrophages
Fuel reduction in coastal squid jigging boats equipped with various combinations of conventional metal halide lamps and low-energy LED panels
Application of the low-energy light emitting diode (LED) is considered as a possible measure for fuel saving in the squid jigging fishery. We monitored fuel consumption of 14 coastal squid jigging boats ranging in size from 6.6 to 19. gross tons (GT) operating in the northern and western waters of the Sea of Japan in 2009-2011. In summer in the northern waters, squid boats of 19. GT consumed approximately 900. l in one operation that lasted from the afternoon to the next morning and 54% of the fuel was used during jigging with 53 conventional metal halide lamps (MHs) of 159. kW in total. In winter in the western waters, the total amount of fuel consumed in conventional operations of the 6.6-16. GT boats was less, but fuel consumption during jigging with lamps accounted for 70-78% of the total consumption due to close fishing grounds. The relationship between fuel consumption (l) and energy (kW. h) during jigging with lamps was expressed as a linear regression containing effects of the boat size and the inherent character of each boat. Fuel consumption rate decreases on average 0.28. l/kW. h by using LEDs with a reduced number of MHs. When 9. kW LEDs were employed with 24. MHs for 19. GT boat in the western water in summer, 24% fuel saving was estimated
コード クローン ノ フクザツド メトリクス ヲ モチイタ カイハツシャ ノ トクチョウ ブンセキ
ソフトウェアエンジニアリング最前線2008 : 情報処理学会SEシンポジウ
- …