Research on mitigation of the interaction of sea turtle with pelagic longline fishery in the western North Pacific

December 13-14, 2006, Siam City Hotel, Bangkok, ThailandWe conducted shallow-set longline fishing operations on a research vessel in the western North Pacific, May-July, 2002-2004. We investigated sea turtle interaction with a pelagic longline fishery and preliminarily examined the potential gear modifications (bait and hook types) for reducing sea turtle bycatch or mortality. A total of 54 loggerhead sea turtle Caretta caretta were caught in 76 operations (about 74, 000 hooks), which were all alive. The mean straight carapace length was 67 cm (range: 52 - 82 cm); this suggested most of loggerhead sea turtles caught in this area were sub-adult. Loggerhead sea turtle catches ranged from 19.1 to 24.5 °C in sea surface temperature, which were concentrated in warm water masses in the Kuroshio extension. The Loggerhead sea turtle catch was more frequently observed on hooks hauled after sunrise. For bait type, the catches by mackerel bait were fewer than those by squid bait. In the circle hook trial in 2003, the deep-hooking rates (proportion of deep-hooking (at esophagus or pharynx) to total in numbers) on squid bait were 0.41 and 0.23 in 3.8 sun conventional tuna hook (n = 22) and 3.8 sun Tankichi type circle hook (which had similar size to 3.8 sun conventional tuna hook) (n = 13), respectively, but the difference was not significant (P > 0.05, extended Fisher’s exact test). In 2004 the large 18/0 circle hooks (which had a larger size, compared to 3.8 sun tuna hook) were tested, but its effect was not clarified due to very small catch numbers. Following these researches, we have been conducting sea turtle mitigation studies, with evaluation of their impacts on target and other non-target species catches

Nesting and post-nesting studies of loggerhead turtles (Caretta caretta) at Omaezaki, Japan

Organized by Graduate School of Informatics, Kyoto University ; JSPS Bangkok Liaison Office ; Japanese Society of Bio-logging Science ; Informatics Research Center for Development of Knowledge Society InfrastructureDecember 13-15, 2004, Imperial Tara Hotel, Bangkok, ThailandNesting biology, measurement of body size and mitochondrial (mt) DNA haplotypes of loggerhead turtle, Caretta caretta at Omaezaki Beach, Japan were investigated by collecting data and samples during night observations from 6 July to 6 August 2004. In addition, seven post-nesting females, which nested during this observation period, were tracked by satellite telemetry. A total of 33 females were identified in this observation period. Seven females nested twice, with a mean inter-nesting interval of 18.0 days. Even though our observations did not cover the entire nesting beach and period, the frequency of nesting was estimated at three, using a calculation based on the total number of nests at this beach in this nesting season. The range of straight carapace length (SCL) was from 65.8 to 91.6 cm, and the mean (±SD) size was 81.5±5.83 cm. The SCL of females at Omaezaki Beach is significantly lower than at other nesting sites in Japan based on calculation of 90% confidence intervals for mean SCLs. Two haplotypes were detected among 33 females using mitochondrial (mt) DNA analysis. Composition of these two haplotypes of nesting females at Omaezaki Beach was similar to nesting females at other nesting beaches in Japan. Post-nesting feeding grounds of seven loggerhead turtles released from Omaezaki consist of two areas, the northwestern North Pacific and the East China Sea. It is confirmed that nesting females at Omaezaki Beach were from the two groups using the different post-nesting feeding grounds and these two groups can be distinguished by their body size criterion of 85 cm. If different factors impact females in each feeding ground, monitoring the number of females and the composition of body size can be useful in assessing the impact to females

Involvement of the leaf-specific multidrug and toxic compound extrusion (MATE) transporter Nt-JAT2 in vacuolar sequestration of nicotine in Nicotiana tabacum

Alkaloids play a key role in higher plant defense against pathogens and herbivores. Following its biosynthesis in root tissues, nicotine, the major alkaloid of Nicotiana species, is translocated via xylem transport toward the accumulation sites, leaf vacuoles. Our transcriptome analysis of methyl jasmonate-treated tobacco BY-2 cells identified several multidrug and toxic compound extrusion (MATE) transporter genes. In this study, we characterized a MATE gene, Nicotiana tabacum jasmonate-inducible alkaloid transporter 2 (Nt-JAT2), which encodes a protein that has 32% amino acid identity with Nt-JAT1. Nt-JAT2 mRNA is expressed at a very low steady state level in whole plants, but is rapidly upregulated by methyl jasmonate treatment in a leaf-specific manner. To characterize the function of Nt-JAT2, yeast cells were used as the host organism in a cellular transport assay. Nt-JAT2 was localized at the plasma membrane in yeast cells. When incubated in nicotine-containing medium, the nicotine content in Nt-JAT2-expressing cells was significantly lower than in control yeast. Nt-JAT2-expressing cells also showed lower content of other alkaloids like anabasine and anatabine, but not of flavonoids, suggesting that Nt-JAT2 transports various alkaloids including nicotine. Fluorescence assays in BY-2 cells showed that Nt-JAT2-GFP was localized to the tonoplast. These findings indicate that Nt-JAT2 is involved in nicotine sequestration in leaf vacuoles following the translocation of nicotine from root tissues

On-Demand Density Correction Using Steady-State Plasmas in the LHD Thomson Scattering

In order to measure reliable electron densities of fusion plasmas by using Thomson scattering system, both accurate absolute calibration and long-term stability in the system are required. Even if slight misalignment of some optics occurs, it may cause large errors in measured densities. We propose a new method to obtain correctionfactors to the errors originated from misalignment by using steady-state plasma discharges. In addition to the datacorrection, realignment of the laser beam can be applied als

End-sequencing and characterization of silkworm (Bombyx mori) bacterial artificial chromosome libraries

<p>Abstract</p> <p>Background</p> <p>We performed large-scale bacterial artificial chromosome (BAC) end-sequencing of two BAC libraries (an <it>Eco</it>RI- and a <it>Bam</it>HI-digested library) and conducted an <it>in silico </it>analysis to characterize the obtained sequence data, to make them a useful resource for genomic research on the silkworm (<it>Bombyx mori</it>).</p> <p>Results</p> <p>More than 94000 BAC end sequences (BESs), comprising more than 55 Mbp and covering about 10.4% of the silkworm genome, were sequenced. Repeat-sequence analysis with known repeat sequences indicated that the long interspersed nuclear elements (LINEs) were abundant in <it>Bam</it>HI BESs, whereas DNA-type elements were abundant in <it>Eco</it>RI BESs. Repeat-sequence analysis revealed that the abundance of LINEs might be due to a GC bias of the restriction sites and that the GC content of silkworm LINEs was higher than that of mammalian LINEs. In a BLAST-based sequence analysis of the BESs against two available whole-genome shotgun sequence data sets, more than 70% of the BESs had a BLAST hit with an identity of ≥ 99%. About 14% of <it>Eco</it>RI BESs and about 8% of <it>Bam</it>HI BESs were paired-end clones with unique sequences at both ends. Cluster analysis of the BESs clarified the proportion of BESs containing protein-coding regions.</p> <p>Conclusion</p> <p>As a result of this characterization, the identified BESs will be a valuable resource for genomic research on <it>Bombyx mori</it>, for example, as a base for construction of a BAC-based physical map. The use of multiple complementary BAC libraries constructed with different restriction enzymes also makes the BESs a more valuable genomic resource. The GenBank accession numbers of the obtained end sequences are <ext-link ext-link-type="gen" ext-link-id="DE283657">DE283657</ext-link>–<ext-link ext-link-type="gen" ext-link-id="DE378560">DE378560</ext-link>.</p

Evaluation of the Effectiveness of Light Streamer Tori- Lines and Characteristics of Bait Attacks by Seabirds in the Western North Pacific

To improve the effectiveness of tori-lines it is necessary to evaluate the ability of tori-lines to mitigate seabird bycatch and determine what kind of seabird species gather during line settings, attack the bait and are incidentally caught. We conducted two experiments in the western North Pacific and examined the effectiveness for seabird mitigation of light streamer tori-lines which have no long streamers but many light (short) streamers and are mainly used in the North Pacific area. Firstly, the effectiveness of two different types of tori-line (light streamer (1 m) and long streamer (up to 7 m) tori-line) and of two different colors (yellow and red) of light streamers for seabird bycatch avoidance was evaluated using 567 sets based on data from 20 offshore surface commercial longliners. No significant difference in the bycatch number between the different tori-line types and streamer colors was found. Secondly, we investigated the characteristics of the seabird bycatch in the North Pacific and the effectiveness of three different types of streamers (light, hybrid and modified light types) by detailed observations of seabird attacks using a chartered longline vessel. Although the appearance rate of albatrosses and shearwaters were 40.9% and 27.7%, Laysan albatross was the main seabird species that followed the vessel but shearwaters seldom followed the vessel and did not aggregate during line setting. In all attacks on bait observed during line settings, 81% and 7% were by albatrosses and shearwaters, respectively. In the number of primary attacks by Laysan albatrosses which attacked most aggressively of all seabirds, there were no significant differences among the tori-line types. No individuals of shearwater were caught. The results of both experiments indicated that light streamer tori-lines were as effective as tori-lines with long streamers for mitigating seabird bycatch in the North Pacific

Fragment of an endogenous inhibitor produced in Escherichia coli for calcium-activated neutral protease (CANP) retains an inhibitory activity

AbstractA C-terminal fragment of an endogenous rabbit liver inhibitor for calcium-activated neutral protease (CANP) was produced in Escherichia coli and its inhibitory activity was examined after purification. The truncated inhibitor (373 amino acid residues), which contains two internal repeat structures, inhibits 2 mol CANP whereas the native liver inhibitor (639 residues), containing four internal repeat structures, inhibits 4 mol CANP. This supports the hypothesis that the repeating unit is the functional unit of inhibition. The results also indicate that post-translational modification of the inhibitor is not essential for inhibition