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In normal daily activities, ligaments are subjected to repeated loads, and respond to this environment with creep and fatigue. While progressive recruitment of the collagen fibers is responsible for the toe region of the ligament stress-strain curve, recruitment also represents an elegant feature to help ligaments resist creep. The use of artificial intelligence techniques in computational modeling allows a large number of parameters and their interactions to be incorporated beyond the capacity of classical mathematical models. The objective of the work described here is to demonstrate a tool for modeling creep of the rabbit medial collateral ligament that can incorporate the different parameters while quantifying the effect of collagen fiber recruitment during creep. An intelligent algorithm was developed to predict ligament creep. The modeling is performed in two steps: first, the ill-defined fiber recruitment is quantified using the fuzzy logic. Second, this fiber recruitment is incorporated along with creep stress and creep time to model creep using an adaptive neurofuzzy inference system. The model was trained and tested using an experimental database including creep tests and crimp image analysis. The model confirms that quantification of fiber recruitment is important for accurate prediction of ligament creep behavior at physiological loads.  相似文献   
83.
Specimens of the marine fishes Chaetodon lineolatus (Chaetodontidae), Lethrinus nebulosus (Lethrinidae) and Acanthopagrus bifasciatus (Sparidae) were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt. Fifteen (75%), four (16%) and fourteen (35%) fish, respectively, were found to harbour intestinal trematodes. C. lineolatus was parasitised by Neohypocreadium aegyptense n. sp. (Lepocreadiidae), L. nebulosus by Fairfaxia cribbi n. sp. (Opecoelidae) and A. bifasciatus by Macvicaria chrysophrys (Nagaty & Abdel-Aal, 1969) Bray, 1985 (Opecoelidae). N. aegyptense n. sp. is most similar to N. chaetodoni (Mahavi, 1972), but is smaller and differs in having acinous rather than digitate ovarian lobes, vitelline follicles extending anteriorly to midway between the ventral sucker and the intestinal bifurcation and an external seminal vesicle extending posteriorly to reach the anterior margin of the ovary. The generic diagnosis of Neohypocreadium is amended. F. cribbi n. sp. resembles F. lethini Cribb, 1990, but differs in having relatively smaller gonads, cirrus-sac and eggs, and larger suckers and pharynx. M. chrysophrys, collected from its type-host and locality, is redescribed. Plagioporus saoudi Ramadan, 1985 is considered its synonym.  相似文献   
84.
We describe a generic, GFP-based pipeline for membrane protein overexpression and purification in Escherichia coli. We exemplify the use of the pipeline by the identification and characterization of E. coli YedZ, a new, membrane-integral flavocytochrome. The approach is scalable and suitable for high-throughput applications. The GFP-based pipeline will facilitate the characterization of the E. coli membrane proteome and serves as an important reference for the characterization of other membrane proteomes.  相似文献   
85.
Psorosis is a damaging disease of citrus that is widespread in many parts of the world. Citrus psorosis virus (CPsV), the type species of the genus Ophiovirus, is the putative causal agent of psorosis. Detection of CPsV by laboratory methods, serology in particular is a primary requirement for large-scale surveys but their production has been impaired by the difficulty of obtaining sufficient clean antigen for immunization. Specific PAbs against coat protein were produced in E. coli using recombinant DNA approach. The full length CP gene fragment was amplified by RT-PCR using total RNA extracted from CPsV infected citrus leaves and CP specific primers. The obtained product (1320bp) was cloned, sequenced and sub-cloned into pET-30(+) expression vector. Expression was induced and screened in different bacterial clones by the presence of the expressed protein (48kDa) and optimized in one clone. Expressed CP was purified using batch chromatography under denaturing conditions. Specificity of expressed protein was demonstrated by ELISA before used as antigen for raising PAbs in mice. Specificity of the raised PAbs to CPsV was verified by ELISA and western blotting. The raised PAbs were showed highly effectiveness in screening by ELISA comparing with the commercial antibodies purchased from Agritest, Valanzano, Italy.The expression of CPsV CP gene in E. coli, production of PAbs using recombinant protein as an antigen, the suitability of these antibodies for use in immunodiagnostics against the CPsV Egyptian isolate have been accomplished in this work.  相似文献   
86.
A novel light-induced and diffused photobioreactor based on a polyacrylate light-receiving face and modified polyester rejection sheet is described. In it, the photosynthetic bacterium, Rhodobacter sphaeroides RV, produced H 2 from glutamate as carbon and nitrogen sources, respectively. Light diffusion limit was investigated in terms of light-dependent H 2 production using different culture widths of photobioreactor to show conversion yields of 3.7 to 4.4 mM H 2 /mM lactate up to 2 cm culture width. The maximum efficiency of energy conversion to H 2 was 9.23% using 1 cm culture width with illumination of 300 W/m 2 from a halogen lamp. The reactor could be used to study other light-dependent bioreactions.  相似文献   
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Avermectin at 1 ppm was slightly toxic by contact to the different immature stages of the predacious miteAmblyseius gossipi El-Badry. When immatures ofA. gossipi ingested treated prey on clean leaf discs, the toxicity increased and the resulted ΦΦ oviposited at a significantly lower rate. In contrast, dicofol at 250 ppm was extremely toxic by contact and caused a significant mortality to the immatures when it was ingested. Female mortality increased and fecundity decreased as the time of feeding treated prey increased from 24 h to 192 h. In case of dicofol a permanent depression in reproduction was recorded after feeding treated prey for 144 h. Females ofA. gossipi suffered a depression in reproduction when fed on prey formerly kept on plant leaves treated with avermectin. This depression was reported, only, after 192 h of feeding on prey previously reared on leaves treated with dicofol.   相似文献   
90.
The major storage protein of jackbean (Canavalia ensiformis) has been purified by a protocol involving ammonium-sulphate precipitation, gel filtration and ion-exchange chromatography. The protein was shown by partial amino-acid-sequence data to be homologous to vicilin, a major storage protein of pea (Pisum sativum), and is thus a member of the family of legume 7S proteins exemplified by pea vicilin. This protein is thus referred to as jack-bean vicilin rather than canavalin or precanavalin as previously used. Other properties of the jack-bean vicilin (e.g. subunit relative molecular mass (Mr) and structure, resistance to proteolysis) show similarity to phaseolin, the major 7S storage protein ofPhaseolus vulgaris. Jack-bean vicilin contained no detectable -mannosidase activity, either as isolated from mature or germinating seeds, or after proteolytic treatment. -Mannosidase was also purified from jack beans, and was shown to have a subunit Mr of approx. 120,000; it was separated completely from jack-bean vicilin by a similar protocol to that used for purifying the latter. The -mannosidase was proteolytically cleaved after seed germination, but did not give polypeptides of the same Mr as jackbean vicilin. It was concluded that -mannosidase and jack-bean vicilin are not related proteins.Abbreviations DE diethylaminoethyl - M relative molecular mass - SDS sodium dodecyl sulphate - PAGE polyacrylamide-gel electrophoresis  相似文献   
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