Analysis of mesh breaking loads in cotton gill nets: Possible solution to ghost fishing     

Yoshiki Matsushita  Shusuke Machida  Haruyuki Kanehiro  Fumio Nakamura  Naoto Honda 《Fisheries Science》2008,74(2):230-235

ABSTRACT:   A small number of fishers in Chiba Prefecture of eastern Japan use cotton gill nets to catch Japanese spiny lobster Panulirus japonicus. To examine the advantages of cotton gill nets, we analyzed changes in mesh breaking load of a new cotton gill net used in a fishing operation. A new cotton gill net was also soaked in a seawater tank to simulate ghost fishing conditions. The average mesh breaking load of new cotton mesh was 50.3 N. This value decreased to 19.0 N after 38 days (∼912 h), and after 82 days (∼1968 h) the mesh could be easily torn (breaking load 0.07 N). Under fishing conditions, the cumulative soak time was only 744.4 h over 19 months. The average breaking load at the end of this period was 43.1 N, a strength 86% that of the presoaked mesh. The mesh breaking load of a cotton gill net continuously soaked for 744.4 h was 26.1 N, as estimated from tank experiment data. Thus, a cotton gill net maintains reasonable strength under typical use conditions, but will degrade if lost at sea.  相似文献   

Identification and phylogenetic analysis of Babesia parasites in domestic dogs in Nigeria     

Haruyuki HIRATA  Temidayo OMOBOWALE  Olufunke ADEBAYO  Nodoka ASANUMA  Asako HARAGUCHI  Yoshiki MURAKAMI  Kodai KUSAKISAKO  Keiko IKEDA  Mitsuhiko ASAKAWA  Kazuyuki SUZUKI  Chiaki ISHIHARA  Hiromi IKADAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):338

The present study examined the presence of Babesia parasites in 104 domestic dogs in Nigeria. Sequentially, Babesia parasites infecting domestic dogs underwent genetic and phylogenetic analyses. The results of nested PCR based on the Piroplasmida 18S rRNA gene illustrated that 13.5% (14/104) of the samples were positive. The obtained positive samples determined the nucleotide sequences of the 18S rRNA genes. In the genetic and phylogenetic analyses, four of five nucleotide sequences were similar to Babesia canis rossi, and one sample exhibited a close similarity to a Babesia sp. isolated from a raccoon in Hokkaido, Japan. The present study revealed the widespread presence of B. canis rossi among domestic dogs in Nigeria.  相似文献   

Inverse analysis to estimate site‐specific parameters of a mathematical model for simulating pesticide dissipations in paddy test systems     

Kei Kondo  Yoshiki Wakasone  Kazuaki Iijima  Kazutoshi Ohyama 《Pest management science》2019,75(6):1594-1605

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Effective Synthesis and Antifouling Activity of Dolastatin 16 Derivatives     

Loida O. Casalme  Keisuke Katayama  Yoshiki Hayakawa  Kensuke Nakamura  Arisa Yamauchi  Yasuyuki Nogata  Erina Yoshimura  Fuyuhiko Matsuda  Taiki Umezawa 《Marine drugs》2022,20(2)

Some derivatives of dolastatin 16, a depsipeptide natural product first obtained from the sea hare Dolabella auricularia, were synthesized through second-generation synthesis of two unusual amino acids, dolaphenvaline and dolamethylleuine. The second-generation synthesis enabled derivatizations such as functionalization of the aromatic ring in dolaphenvaline. The derivatives of fragments and whole structures were evaluated for antifouling activity against the cypris larvae of Amphibalanus amphitrite. Small fragments inhibited the settlement of the cypris larvae at potent to moderate concentrations (EC₅₀ = 0.60-4.62 μg/mL), although dolastatin 16 with a substituent on the aromatic ring (24) was much less potent than dolastatin 16.  相似文献   

Numerical experiments of watershed-scale soil water movement and bedrock infiltration using a physical three-dimensional simulation model     

Katsushige Shiraki  Yoshiki Shinomiya  Hirofumi Shibano 《Journal of Forest Research》2006,11(6):439-447

Numerical experiments of soil water movement and bedrock infiltration based on a simplified simulation method were conducted to analyze watershed-scale rainfall-runoff processes. To verify the model accuracy, it was applied to a Minamitani watershed (0.45 ha). The simulation was performed with 2.5-m space grids horizontally and five cells vertically. Results of long-term calculation of this model proved that this simulation model is robust and demonstrated good computational water mass conservation. Calculation results showed the best agreement with observed hydrographs and the number of groundwater levels simultaneously when laboratory-tested soil hydraulic characteristics for topsoil were used and infiltration into bedrock was included in numerical calculations. Numerical experiments show that bedrock infiltration generated a stable base flow and suppressed the secondary discharge peak. The reproducibility achieved by observed soil hydraulic characteristics with the assumption of bedrock flow demonstrates the effectiveness of the simulation model used in this article for analyses of watershed-scale soil water movements.  相似文献   

Methylation of free-floating deoxyribonucleic acid fragments in the bronchoalveolar lavage fluid of dogs with chronic bronchitis exposed to environmental tobacco smoke     

Yoshiki Yamaya  Hiroshi Sugiya  Toshihiro Watari 《Irish veterinary journal》2015,68(1)

Background

The etiology of canine chronic bronchitis (CB) is not completely understood, although exposure to environmental tobacco smoke (ETS) affects the airway inflammatory responses in some dogs with CB. The mechanism by which this occurs is unknown.

Findings

We investigated the concentrations and methylation rates of free-floating DNA fragments in bronchoalveolar lavage fluid (BALF) from dogs with chronic bronchitis. Based on serum cotinine levels, dogs with CB were divided into 2 groups: dogs that either had or had not been exposed to ETS. Our results demonstrated that the total nucleated cell and macrophage numbers increased in BALF of ETS-exposed dogs with CB. There were no significant differences in DNA concentrations and methylation rates in BALF between the 2 groups. However, 3 out of 8 dogs exposed to ETS had high DNA methylation rates in their BALF samples.

Conclusion

Our results suggest that ETS exposure leads to epigenetic modifications of cellular components in BALF in dogs diagnosed with CB.  相似文献   

Increased proportions of CCR4+ cells among peripheral blood CD4+ cells and serum levels of allergen-specific IgE antibody in canine chronic rhinitis and bronchitis     

Yoshiki YAMAYA  Toshihiro WATARI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):421-425

Canine chronic rhinitis (CR) and bronchitis (CB) are suspected to be allergic diseases. The present study tested whether dogs diagnosed with CR or CB present an atopic predisposition based on the ratio of CC chemokine receptor 4 (CCR4)-positive cells among peripheral blood CD4-positive cells (CCR4/CD4) and the serum levels of allergen-specific IgE antibodies. We found that most dogs with CR and CB have a possibility of atopic predisposition, and macrolide therapy constitutes an alternative to corticosteroid therapy in controlling the clinical signs.  相似文献   

Near-infrared spectroscopy as a potential method for identification of anatomically similar Japanese diploxylons     

Yoshiki Horikawa  Suyako Mizuno-Tazuru  Junji Sugiyama 《Journal of Wood Science》2015,61(3):251-261

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Histone H4 Modification During Mouse Spermatogenesis     

Yoshiki SHIRAKATA  Yuuki HIRADATE  Hiroki INOUE  Eimei SATO  Kentaro TANEMURA 《The Journal of reproduction and development》2014,60(5):383-387

The core histone is composed of four proteins (H2A, H2B, H3 and H4). Investigation of the modification patterns of histones is critical to understanding their roles in biological processes. Although histone modification is observed in multiple cells and tissues, little is known about its function in spermatogenesis. We focused on the modification patterns of histone H4 during murine spermatogenesis. We demonstrated that the individual N-terminal sites of H4 show different modification patterns during the differentiation of male germ cells. The methylation pattern varied depending on the residues that were mono-, di-, or tri-methylated. All the H4 modifications were high during the meiotic prophase, suggesting that histone H4 modification plays an important role during this stage of spermatogenesis. Elongating spermatids showed increased acetylation of histone H4, which may be associated with a histone-to-protamine substitution. Our results provide further insight into the specific relationship between histone H4 modification and gene expression during spermatogenesis, which could help to elucidate the epigenetic disorders underlying male infertility.  相似文献   

Genetic tracing shows segregation of taste neuronal circuitries for bitter and sweet     

Sugita M  Shiba Y 《Science (New York, N.Y.)》2005,309(5735):781-785

The recent discovery of mammalian bitter, sweet, and umami taste receptors indicates how the different taste qualities are encoded at the periphery. However, taste representations in the brain remain elusive. We used a genetic approach to visualize the neuronal circuitries of bitter and sweet tastes in mice to gain insight into how taste recognition is accomplished in the brain. By selectively expressing a transsynaptic tracer in either bitter- or sweet and/or umami-responsive taste receptor cells, and by comparing the locations of the tracer-labeled neurons in the brain, our data revealed the potential neuronal bases that underlie discrimination of bitter versus sweet.  相似文献