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901.
The tobacco mosaic virus (TMV) provides an attractive means of producing foreign peptides in plants. In this study, a TMV-based vector was designed such that a fragment encoding 15 amino acids of the poliovirus peptide (PVP) derived from the viral capsid proteins VP3 and VP1 of poliovirus type 1 Sabin was inserted downstream of the six-base 3' context nucleotide sequence of the TMV coat protein (CP) gene. This design allowed readthrough at the amber stop codon, thereby producing the chimeric TMV particle with both intact CP and CP-fusion protein (CP-PVP) in Nicotiana tabacum cv. Samsun infected with the TMV vector. The TMVCP-PVP virus particle induced antibodies against PVP as well as TMVCP in mice after intraperitoneal immunization. These data illustrate the potential of the readthrough translation system with TMVCP for antigen presentation and vaccine production.  相似文献   
902.
Inferring genetic networks from gene expression data is the most challenging work in the post-genomic era. However, most studies tend to show their genetic network inference ability by using artificial data. Here, we developed the fuzzy adaptive resonance theory associated matrix (F-ART matrix) method to infer genetic networks and applied it to experimental time series data, which are gene expression profiles of Saccharomyces cerevisiae responding under oxidative stresses such as diamide, heat shock and H2O2. We preprocessed them using the fuzzy adaptive resonance theory and successfully identified genetic interactions by drawing a 2-dimensional matrix. The identified interactions between diamide and heat shock stress were confirmed to be the common interactions for two stresses, compared with the KEGG metabolic map, BRITE protein interaction map, and gene interaction data of other papers. In the predicted common genetic network, the hit ratio was 60% for the KEGG map. Several gene interactions were also drawn, which have been reported to be important in oxidative stress. This result suggests that F-ART matrix has the potential to function as a new method to extract the common genetic networks of two different stresses using experimental time series microarray data.  相似文献   
903.
The nitrogen solubility in liquid Fe-Cr-Ni alloys containing Mo or Mn was determined by the Sieverts’ method. The first and second order mutual interactions among nitrogen, chromium, nickel, molybdenum, and manganese in iron were determined as a function of temperature. The heat and entropy of solution in these alloys were correlated as functions of the logarithm of the activity coefficient of nitrogen at {dy1873} K independent of the composition of the alloys. An equation was derived to predict the nitrogen solubility in liquid multicomponent iron alloys for the range from logfN, 1873K = 0 to -1.4 as, log (wt pct N)T = (-247/T - 1.22) - (4780JT - 1.51) (logfn, 1873K)-(1760/T -0.91) (logfN,{dy1873}K )2.  相似文献   
904.
Electrochemical oxidation and reduction of H2O2 on Ag were studied in alkaline solution of 10?3?0.3 M H2O2 and 2 × 10?3 ?1.0 M KOH under N2 bubbling. Steady i-φ curves obtained by a cyclic potential sweep method in a potential range where no electrode oxidation takes place, lead to the following results: (1) icd (A cm?2) (cathodic limiting current density) = 1.0 × [H2O2]1.0T (M), (2) i1d (A cm?2 (anodic limiting one) = icd ([KOH] ? [H2O2]T) or 1.0 × [KOH] < [H2O2]T), (3) φm (V) (mixed potential) = 0.126-0.060 log [KOH]1.0 and (4) (?φ/?i)φ=φm (Ωcm2) (reaction resistance at φ = φm) = 0.057 × [H2O2]?1.0T (M?1), where [H2O2]T designates a total H2O2 concentration and the others have their usual meanings.The above results are explained by the following mechanism; HO?2 formed by the reversible chemical reaction, H2O2 + OH ? HO?2 + H2O, is oxidised in anodic reaction by two steps: HO?2
HO2 (a) + e? and HO2(a) + OH? → O2 + H2O + e?, whereas in cathodic reaction, H2O2 is reduced by H2O2 + e?
OH(a) + OH?, OH(a) + e? → OH?. Here,
designates a rate determining step,Catalytic decomposition of H2O2 on the electrode is also discussed.  相似文献   
905.
A forced oscillation method applying reverse-piezo electric effect has been proposed for mass-production of biocatalyst-entrapping polymer gel particles. A jet of aqueous alginate solution flowing out through an orifice was disintegrated into droplets by an oscillating pressure which was exerted by a ceramic plate vibrated by the reverse-piezo electric effect. The droplets formed were immediately solidified into gel particles in calcium chloride solution.

The particle production rate by the method was up to 270 particles s-1 or 1 × 10-6m3.s-1 The size of the particles produced were down to I mm depending on the applied frequency. The smallest matrix size of the gel's polymer network was estimated to be around 5 nm.

The method was applied for immobilization of yeast cells. The diameter of immobilized particles was 2.5 mm. The immobilized yeast grew well in the particle. The damage of yeast cells caused by the immobilization was not remarkable  相似文献   
906.
1) In congenital heart disease with pulmonary hypertension, the place for surgical correction still remains even with almost systemic PA pressure if R to L shunt ratio on lung scintigram is lower than 25%. 2) The patient with pulmonary hypertension in congenital heart disease younger than 3 years of age has wider acceptability for surgery compared to older patient. 3) In patients with mitral valvular disease, surgical correction seems to be indicated irrespective of PA pressure, if their preoperative U/L are lower than 2.4.  相似文献   
907.
A physical model of gas–liquid two-phase annular flow regime is presented for predicting the enhanced evaporation heat transfer characteristics in horizontal microfin tubes. The model is based on the equivalence of a periodical distortion of the disturbance wave in the substrate layer. Corresponding to the stratified flow model proposed previously by authors, the dimensionless quantity Fr0 = G/[gdeρv(ρl ? ρv)]0.5 may be used as a measure for determining the applicability of the present theoretical model, which was used to restrict the transition boundary between the stratified-wavy flow and the annular/intermittent flows. Comparison of the prediction of the circumferential average heat transfer coefficient with available experimental data for four tubes and three refrigerants reveals that a good agreement is obtained or the trend is better than that of the previously developed stratified flow model for Fr0 > 4.0 as long as the partial dry out of tube does not occur. Obviously, the developed annular model is applicable and reliable for evaporation in horizontal microfin tubes under the case of high heat flux and high mass flux.  相似文献   
908.
Planar type Gunn effect devices have been fabricated by sulfur-ion implantation into the Cr doped semi-insulating GaAs substrates. The high doping efficiency as 90% was obtained as a result of long heat treatment. The mobility of the sulfur-ion implanted n layers with average carrier concentration of 4 × 1016cm?3 was 5200 cm2/Vsec at room temperature and 12,000 cm2/Vsec at 77 K. The minimum gate trigger voltage of the Gunn effect digital devices was 100 mV. Sulfur-ion implanted Gunn effect devices have shown superior current drop ratio dependence on doping-depth product, compared to the devices prepared from the epitaxial layer.  相似文献   
909.
For the purpose of separating alcohol–water mixtures by the use of the pervaporation technique, new composite membranes composed of polyion complexes (PIC) as a separating layer were developed. The polyion complex structure, consisting of polyacrylic acid (PAA) and polycation, provided excellent permeation rate and selectivity. Among the polycations, ionenes, which have quaternary ammonium groups in the backbone chain, were effective in giving membranes of higher permselectivities. High selectivity of PIC membranes was observed at high ethanol concentration regions in the feed mixture. For the azeotropic mixture of water/ethanol (95 wt % EtOH) at 60°C, the PAA-based PIC membrane had the following separation properties: separation factor ~ 3,500 and permeation rate ~ 1.6 kg/m2 h.  相似文献   
910.
An efficient downstream process for the production of recombinant human growth differentiation factor 5 (rhGDF5) has been developed for industrial application utilizing a novel "direct refolding" method. In this method, the starting material is an inclusion body produced in Escherichia coli, and the critical step is the direct refolding step that follows directly after solubilization of the inclusion body. rhGDF5 can be refolded at a markedly high concentration of 2.4 mg.ml(-1), which is 24 times that hitherto achieved by the proteins of the TGF-beta superfamily. The refolding yield is 63%, and after purification by diafiltration, isoelectric precipitation and reverse-phase chromatography, the final purification yield is 20% with purity higher than 99%. The yield is more than twice that of a conventionally established process having three chromatography steps and the purity is equivalent. The first pilot-scale trial shows a refolding yield of 51% and a final yield of 11%. The final yield is 1.4 times that of the conventional process, and further optimization at pilot-scale is expected to bring this figure up to or above that of laboratory-scale. As a result, the calculated production cost of rhGDF5 has been reduced dramatically. This type of efficient and simple process is beneficial particularly in the large-scale production of recombinant proteins in which high yield and quality are required.  相似文献   
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