Estimation of gillnet selectivity curve by maximum likelihood method   总被引：2，自引：0，他引：2  

Yasuzumi Fujimori  Tadashi Tokai 《Fisheries Science》2001,67(4):644-654

ABSTRACT: A maximum likelihood method of estimating gillnet selectivity when data are obtained by gillnet fleets consisting of several nets of differing mesh size is presented in this paper. The SELECT model is expanded by application of the relative length (i.e. the ratio of fish length to mesh size) to obtain a master curve of gillnet selectivity. Four kinds of functional model, normal, lognormal, skew-normal and bi-normal are fitted to the data. In addition, two cases in which the relative fishing intensity is either estimated or fixed by catch effort are compared. The bi-normal model has the lower model deviance regardless of whether the relative fishing intensity is estimated or not. The estimation of relative fishing intensity by catch effort is also examined in which the estimates of the parameter of the SELECT model are compared with the catch effort as determined by the number of nets of each mesh size used. For the bi-normal model these quantities compare well. Thus, it is concluded that this method gives reliable estimates even if data for each mesh size is obtained with different catch efforts.  相似文献   

日本沿海捕鳗笼的网目选择性     

葛长字  梁振林  东海正 《南方水产》2006,2(1):58-61

1995~2000年在东京湾进行的套网法实验,结果表明:网目尺寸为21·0、18·1、15·5、13·6、11·6mm的笼网目选择率在星康吉鳗全长035·50cm、l>32·50cm、l>27·50cm、l>26·50cm、l>24·00cm时,全长选择率几乎接近于1·00,50%选择全长分别为29·80、26·80、23·00、22·00、20·00cm;选择域为3·80、4·30、3·50、3·00、3·00cm。依据AIC理论,套网和实验网的网目接近时,套网的影响显著;Single curve model所得到的主选择性曲线可更好地反映网目选择性。50%选择相对体周长MGc1·11,选择域为0·52。01·60,选择率趋向于1·00。  相似文献   

Assessment of criteria for improvement in Theileria orientalis sergenti infection tolerance     

Michiru FUKASAWA  Tadashi KIKUCHI  Shigeru KONASHI  Akira NISHIDA  Toshihiro YAMAGISHI 《Animal Science Journal》2003,74(1):67-72

We examined the relationships between calf productivity, anemia and Theileria orientalis sergenti infection from records of 109 Japanese shorthorn calves during a grazing period and we quantified the relative importance of the T. orientalis sergenti infection‐resistance criteria used. A decrease in average parasitemia (AvePara) and an increase in average packed cell volume (AvePCV) would cause a decrease in the number of drug treatments. An increase in AvePCV would decrease the number of drug treatments more efficiently than a decrease in AvePara. An increase in AvePCV would cause an increase in dairy gain, while a decrease in AvePara would cause a decrease in dairy gain. Therefore, an improvement in the capacity to control anemia development would improve T. orientalis sergenti infection resistance more efficiently than an improvement in the capacity to control parasitemia development.  相似文献   

Comprehensive Analysis of Plant Gene Expression in Soybean Root Nodules at Different Growth Stages     

Sirilak Kaewsuralikhit  Tadashi Yokoyama  Hirochi Kouchi  Yasuhiro Arima 《Soil Science and Plant Nutrition》2005,51(4):535-547

Gene expression profiles in early (12 d after sowing, DAS), mature (35 DAS) and senescent (77 DAS) soybean ( Glycine max (L.) Merr. cv. Enrei) root nodules were analyzed using Lotus japonicus cDNA macroarray. The cDNA macroarray membranes contained 18,144 independent cDNAs of L. japonicus isolated from various organs. The membranes were hybridized to ³³P-labeled single-strand cDNAs transcribed from mRNA extracted from the soybean root nodules at three different growth stages. The results showed that over 75% of the cDNA clones gave a relative signal intensity (RSI) lower than 300, irrespective of the soybean growth stage. cDNA with an RSI value over 5,000 accounted for 2.1, 1.2 and 0.5% of the total cDNA clones at 12, 35 and 77 DAS, respectively. The highest RSI value was detected in a clone hybridized to putative pectinesterase (MWM097c10_r) at 12 DAS, while the RSI value of lycopene β-cyclase (MWL025d06_r) was the highest at 35 and 77 DAS. At 77 DAS, the percentage of transferase gene cDNA clones accounted for 20.5% of the total cDNA clones showing an RSI value over 500, a value clearly lower than that at 12 and 35 DAS. On the other hand, the percentage of hydrolase gene cDNA clones accounted for 45.2% at 77 DAS, a value around 1.5 times higher than that at 12 and 35 DAS. The chronological RSI profiles of individual cDNA clones were classified into nine patterns, and the profiles of the cDNA clones belonging to 15 homologous gene groups encoding enzymes of nitrogen and carbon metabolism, nodule specific proteins, enzymes of RNA and protein hydrolysis, and synthesis of jasmonic acid precursor were compared within and between groups. As a result, significant variations both within- and between-groups were revealed.  相似文献   

Structural unit of xylans from sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) and hinoki (<Emphasis Type="Italic">Chamaecyparis obtusa</Emphasis>)     

Takashi Yamasaki  Ayumi Enomoto  Atsushi Kato  Tadashi Ishii  Kazumasa Shimizu 《Journal of Wood Science》2011,57(1):76-84

Arabinoglucuronoxylans (AGXs) isolated from the holocellulose of sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) contained one 4-O-methyl-d-glucopyranosyluronic acid (4-O-Me-d-GlcAp) residue per 6.2 d-xylopyranose (d-Xylp) residues and one 4-O-Me-d-GlcAp residue per 3.8 d-Xylp residues. These AGXs were subjected to partial acid hydrolysis. Analyses by size exclusion chromatography and electrospray-ionization mass spectroscopy of the neutral sugar fractions in the hydrolysates showed the presence of xylooligosaccharides having a degree of polymerization of 2-8 in addition to d-Xyl, suggesting that the AGXs from sugi and hinoki contained unsubstituted chains consisting of at least eight d-Xyl residues. The acidic sugars in the hydrolysates were separated into two series of aldouronic acids composed of 4-O-Me-d-GlcAp and d-Xylp by ion-exchange chromatography. The first series included aldouronic acids from aldobiouronic acid (4-O-Me-d-GlcAp-Xyl) to aldopentaouronic acids (4-O-Me-d-GlcAp-Xyl₄). The second series were aldouronic acids composed of two 4-O-Me-d-GlcAp residues and 2-4 d-Xyl residues. In these acidic sugars, the uronic acid side chains were located on two contiguous d-Xyl residues. These facts indicated that AGXs from sugi and hinoki had a structural unit containing two 4-O-Me-d-GlcAp residues on two contiguous d-Xyl residues as well as AGXs from spruce and larch.  相似文献   

Isolation and characterization of a novel immunomodulatory alpha-glucan-protein complex from the mycelium of Tricholoma matsutake in basidiomycetes     

Hoshi H  Yagi Y  Iijima H  Matsunaga K  Ishihara Y  Yasuhara T 《Journal of agricultural and food chemistry》2005,53(23):8948-8956

Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats. In this study, a sodium hydroxide extract of CM6271 was defatted followed by fractionation with a combination of ion exchange chromatography and gel filtration in order to identify the components involved in the expression of the activity, and a single peak fraction (MPG-1) was obtained with reversed phase chromatography. MPG-1 was a glycoprotein (sugar:protein ratio, 94.3:5.7) with a relative molecular mass of 360 kDa, and the sugar moiety contained about 90% glucose. NMR spectra and methylation analysis revealed that the alpha-1,4-linkage was the predominant glucan linkage with alpha-1,6- and alpha-1,2-linkages in the minority. The amino acid composition in the protein moiety was rich in glutamine, alanine, asparagine, leucine, glycine, valine, serine, threonine, isoleucine, and proline. MPG-1 was resistant to degradation with amylase or protease. The oral administration of MPG-1 promoted, in a dose-dependent manner, the recovery of the mouse natural killer cell activity and serum IL-12 level that had been reduced by the loading of restraint stress. The dose of MPG-1 (25 mg/kg) required for the expression of the effect decreases to 1/12 of that of CM6271 (300 mg/kg). Furthermore, MPG-1 formed a complex with TGF-beta1 in vitro, modulating the biological activity of TGF-beta1 by binding to its active form. These results indicate that the mycelium of T. matsutake contains a novel alpha-glucan-protein complex with immunomodulatory activities.  相似文献   

A New Approach for Characterization of Single Raindrops     

Chang-Jin Ma  Mikio Kasahara  Susumu Tohno  Tomihiro Kamiya 《Water, air, and soil pollution》2001,130(1-4):1601-1606

To determine the characteristics of single raindrops as a function of their size, the collodion film method was newly applied to the sampling of single raindrops. Sampling of single raindrops was performed at a height of 20 m above ground level of the Kyoto University building located in Uji, Japan during rain events from September to November 1999. It was possible to get successfully replicas of raindrop by collodion film method. And we tried to analyze the elemental components of the nuclei and pollutants that were incorporated into the developing raindrop. To the analysis of single raindrops, Particle Induced X-ray Emission (PIXE) was applied. Several elements including S in single raindrops were detected by PIXE. The concentrations of every element increased with decreasing drop diameter. Furthermore, to acquire more detailed information such as inner-structure and mixing state in single raindrops, micro-PIXE analysis was performed. The nucleation centers of single raindrops were successfully analyzed by micro-PIXE. Ca, S and Fe were apparently detected by scanning beam of 1 ～ 2 µm diameter and about 70 pA beam current.  相似文献   

Displacement above the hypocenter of the 2011 Tohoku-Oki earthquake   总被引：3，自引：0，他引：3  

Sato M  Ishikawa T  Ujihara N  Yoshida S  Fujita M  Mochizuki M  Asada A 《Science (New York, N.Y.)》2011,332(6036):1395

The moment magnitude (M(w)) = 9.0 2011 Tohoku-Oki mega-thrust earthquake occurred off the coast of northeastern Japan. Combining Global Positioning System (GPS) and acoustic data, we detected very large sea-floor movements associated with this event directly above the focal region. An area with more than 20 meters of horizontal displacement, that is, four times larger than those detected on land, stretches several tens of kilometers long along the trench; the largest amount reaches about 24 meters toward east-southeast just above the hypocenter. Furthermore, nearly 3 meters of vertical uplift occurred, contrary to observed terrestrial subsidence.  相似文献   

Regulation of spermatogenesis by testis-specific,cytoplasmic poly(A) polymerase TPAP     

Kashiwabara S  Noguchi J  Zhuang T  Ohmura K  Honda A  Sugiura S  Miyamoto K  Takahashi S  Inoue K  Ogura A  Baba T 《Science (New York, N.Y.)》2002,298(5600):1999-2002

  相似文献   

Antioxidant constituents of radish sprout (Kaiware-daikon), Raphanus sativus L   总被引：2，自引：0，他引：2  

Takaya Y  Kondo Y  Furukawa T  Niwa M 《Journal of agricultural and food chemistry》2003,51(27):8061-8066

Methanol extracts of 11 kinds of commonly available vegetables were examined for hydroxyl radical scavenging potency using the bleomycin-Fe method. In this method, the iron ion and bleomycin in water form hydroxyl radicals, and the scavenging activity is monitored by the modified thiobarbituric acid method. All extracts showed scavenging capacity, even though the activity of some of them was lower than that of l-ascorbic acid. Those vegetables were classified into three groups according to their activity, groups showing strong activity, moderate activity, and weak activity, as compared to the activity of l-ascorbic acid at the same concentration. Among them, the methanol extract of radish sprout (Japanese name "kaiware-daikon") exhibited the highest potency (1.8 times as l-ascorbic acid). Then, we investigated the constituents of the methanol extract of radish sprout and the contribution to the overall activity of each compound by examining their activity. As the result, several kinds of sinapinic acid esters and flavonoids were isolated with high radical scavenging potency, which must contribute substantially to the activity.  相似文献