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11.
Oishi K  Hirooka H 《Theriogenology》2012,77(2):320-330
The effects of sex control and twinning techniques on determination of optimal culling parity of cows in beef cow-calf production systems were deterministically analyzed using a herd model simulation. The model simulated the annualized net revenue as an economic indicator during the whole life cycle of a cow. Biological factors (survivability, growth, reproduction, and feed requirements) and economic factors (returns from sales of live calves and cows' carcasses and production costs) were included in the model. Some biological and economic parameters relating to these factors were altered from a base condition in order to adapt the production systems with sex control and twinning techniques. Based on the model, early culling was optimal for all production systems when biological efficiency was used as an indicator of production; however, later culling was optimal for single production, but slightly earlier culling was optimal for twin production, when annualized net revenue was evaluated. The introduction of sex control did not greatly affect the determination of the optimal culling parity of cows. When production included the sex control, female sexing increased biological efficiency, whereas male sexing increased annualized net revenue. In the present beef cow-calf production circumstances in Japan, introduction of sex control did not have economically appreciable effects, but twinning was economically beneficial. For production involving sex control, improvement in the conception rate per mating and/or reduction of technical cost were required for this technology to be profitable.  相似文献   
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A solution gate field effect transistor (SGFET) using an oxidised boron δ-doped channel on (111) diamond is presented for the first time. Employing an optimised plasma chemical vapour deposition (PECVD) recipe to deposit δ-layers, SGFETs show improved current-voltage (I-V) characteristics in comparison to previous similar devices fabricated on (100) and polycrystalline diamond, where the device is shown to operate in the enhancement mode of operation, achieving channel pinch-off and drain-source current saturation within the electrochemical window of diamond. A maximum gain and transconductance of 3 and 200μS/mm are extracted, showing comparable figures of merit to hydrogen-based SGFET. The oxidised device shows a site-binding model pH sensitivity of 36 mV/pH, displaying fast temporal responses. Considering the biocompatibility of diamond towards cells, the device's highly mutable transistor characteristics, pH sensitivity and stability against anodic oxidation common to hydrogen terminated diamond SGFET, oxidised boron δ-doped diamond SGFETs show promise for the recording of action potentials from electrogenic cells.  相似文献   
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The objective of this study was to investigate growth patterns of goats utilizing data from a crossbreeding program involving the exotic German Fawn (GF) and the indigenous Kambing Katjang (KK) goats. Growth curve models and growth curve parameters were compared and analyzed for different genotypes and litter types. A total of 20,393 weight–age data from 208 female goats belonging to various crossbreeding genotypes were individually fitted to four growth curve models (Brody, Bertalanffy, Gompertz and Logistic). The goodness of fit was highest in the Brody model in most cases. A comparison of R2 among genotypes showed that they were highest for KK. There were no significant differences of genotypes for estimated mature weight in the Brody model. The estimated mature weights for KK were significantly lower (P < 0.05) than for GF × KK (F1), backcrosses with 75% GF genes (BC) and F1 × F1 (F2) in the other models. The correlations between estimated mature weights and the maturing rates were lowest for BC. The genotype significantly (P < 0.01) affected the age at the constant degree of maturity (67% and 90% of mature weight) in all models. The BC genotype was the youngest at maturity and KK the oldest. All models well expressed the growth pattern of the target animals when they were older than 2.5 years of age. The results from the present study showed that the growth pattern may be altered by crossbreeding of KK with the GF breed.  相似文献   
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New application of fluorescence probe to detect apoplastic redox radicals from plant roots were sought. This probe can detect radicals selectively. Calibration curve for radicals was obtained using nitrogen monoxide as radical standard produced by NOC7. Apoplastic radicals released constitutively were quantified and the release rate was 60 μmol L?1 h?1. Oxidative burst triggered by chitin was distinguished from constitutive radical release.  相似文献   
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Gibellulopsis chrysanthemi sp. nov. is described and illustrated from specimens on rotten leaves of garland chrysanthemum (Chrysanthemum coronarium L. var. spatiosum L.H. Bailey), collected in three different sites of Osaka Prefecture, Japan. This species is characterized by having short and long verticillium-like conidiophores, 1-septate, long-cylindrical conidia with tapering ends and slightly brownish chlamydospores. Compared morphologically with other species in the Plectosphaerellaceae (sister to the Glomerellales), G. chrysanthemi is similar to Gibellulopsis nigrescens, from which it differs in the formation of long conidiophores and 1-septate, long-cylindrical conidia with tapering ends. In addition, the molecular analyses of G. chrysanthemi and other members of the Plectosphaerellaceae based on a phylogenetic tree with three-loci (ITS, D1/D2, tef1-α) sequences reveal that G. chrysanthemi is located as a sister group of G. nigrescens.  相似文献   
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To investigate the mechanism for low pH adaptation by a carboxylesterase, structural and biochemical analyses of EstFa_R (a recombinant, slightly acidophilic carboxylesterase from Ferroplasma acidiphilum) and SshEstI (an alkaliphilic carboxylesterase from Sulfolobus shibatae DSM5389) were performed. Although a previous proteomics study by another group showed that the enzyme purified from F. acidiphilum contained an iron atom, EstFa_R did not bind to iron as analyzed by inductively coupled plasma MS and isothermal titration calorimetry. The crystal structures of EstFa_R and SshEstI were determined at 1.6- and 1.5-Å resolutions, respectively. EstFa_R had a catalytic triad with an extended hydrogen bond network that was not observed in SshEstI. Quadruple mutants of both proteins were created to remove or introduce the extended hydrogen bond network. The mutation on EstFa_R enhanced its catalytic efficiency and gave it an alkaline pH optimum, whereas the mutation on SshEstI resulted in opposite effects (i.e. a decrease in the catalytic efficiency and a downward shift in the optimum pH). Our experimental results suggest that the low pH optimum of EstFa_R activity was a result of the unique extended hydrogen bond network in the catalytic triad and the highly negatively charged surface around the active site. The change in the pH optimum of EstFa_R happened simultaneously with a change in the catalytic efficiency, suggesting that the local flexibility of the active site in EstFa_R could be modified by quadruple mutation. These observations may provide a novel strategy to elucidate the low pH adaptation of serine hydrolases.  相似文献   
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