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71.
Interferon-gamma (IFN-γ), a cytokine produced by sensitized T lymphocytes, is one of the key elements in defining T helper 1 lymphocyte immune responses. Quantitative evaluation of IFN-γ expression could provide an important analytical tool for measurement of cell-mediated immunity and investigating immune responses to infectious diseases. Method of DNA-designed avian IgY antibodies was used for production of monospecific polyclonal antibodies that allows quantification of the recombinant bovine IFN-γ protein. IFN-γ cDNA was subcloned and expressed in mammalian expression plasmid (pcDNA3.1(+)) under the control of the human cytomegalovirus promoter. Chickens were immunized by plasmid DNA, and eggyolk antibodies extracted from eggs were collected after immunization. IgY-specific antibodies were evaluated by an antigen capture enzyme-linked immunosorbent assay (ELISA) using recombinant IFN-γ. Based on the results, developed bovine IFN-γ capture ELISA could detect up to 1 ng/ml of IFN-γ by 64-fold diluted IgY. Monospecific anti-bovine IFN-γ antibodies generated in chickens are useful for quantifying different concentrations of recombinant bovine IFN-γ, which is expressed in cell culture.  相似文献   
72.
General Linear Methods (GLMs) were introduced as the natural generalizations of the classical Runge–Kutta and linear multistep methods. An extension of GLMs, so-called SGLMs (GLM with second derivative), was introduced to the case in which second derivatives, as well as first derivatives, can be calculated. In this paper, we introduce the definitions of consistency, stability and convergence for an SGLM. It will be shown that in SGLMs, stability and consistency together are equivalent to convergence. Also, by introducing a subclass of SGLMs, we construct methods of this subclass up to the maximal order which possess Runge–Kutta stability property and A-stability for implicit ones.  相似文献   
73.
Electrochemical quartz-crystal nanobalance (EQCN) analysis of the behavior of Pt in aqueous H(2)SO(4) reveals that the interfacial mass reaches a minimum, the potential of minimum mass (E(pmm)), at 0.045 V. A similar behavior is observed for Pt in aqueous HClO(4) and NaOH. E(pmm) is a new parameter describing the electrochemical interface. The value of E(pmm) coincides with the completion of the saturation layer of electroadsorbed H (H(UPD)) and the commencement of H(2)(g) generation or H(2)(g) electro-oxidation. The value of E(pmm) and the structure of the Pt/electrolyte interface are discussed in terms of the interactions of the anions H(3)O(+), H(UPD), H(OPD), and H(2)O with Pt. The layer of H(UPD) embedded in the Pt surface lattice minimizes the surface dipole-water dipole and surface charge-water dipole interactions, thus reduces the wetting ability of Pt. Consequently, the discharge of H(3)O(+) in the electrolytic formation of H(2)(g) or the dissociative adsorption of H(2)(g) that precedes its electro-oxidation to H(3)O(+) proceed easily on Pt, because the species do not have to displace H(2)O molecules. Effective and inexpensive non-platinum electrocatalysts for the electrolytic H(2)(g) generation in water electrolyzers or H(2)(g) electro-oxidation in polymer electrolyte membrane fuel cells should mimic the interfacial behavior of Pt by minimizing the interaction of H(2)O molecules with the electrode.  相似文献   
74.
In this work, MOF‐5 composited with Ag2O nanoparticles was prepared and characterized via X‐ray diffraction, field emission‐scanning electron microscopy, energy‐dispersive spectroscopy and FT‐IR analysis. This new material was subsequently employed for removing basic yellow dye [Auramine O (AO)] from aqueous solution under ultrasound irradiation. Several experiments were designed by central composite design in which operational parameters such as such as pH, MOF‐5‐Ag2O mass and initial concentration of AO involved in the process were optimized. The significance of individual parameters and their possible interactions were investigated using analysis of variance (anova ). The optimum values of 6, 0.025 g and 6 mg l?1 were obtained for the pH, MOF‐5‐Ag2O‐NPs mass and the initial concentrations of AO, respectively, with desirability of 1.0. At such conditions, the efficiency for the removal of AO was found to be 89.45%. Various isotherm models for fitting the experimental equilibrium data were studied, and it was found that the Langmuir model has the highest efficiency for correlation of experimental equilibrium data, so that the monolayer adsorption capacity of MOF‐5‐Ag2O for successful removal of AO was 260.70 mg g?1 at optimal conditions.  相似文献   
75.
A dopamine (DA) biosensor was developed based on polypyrrole/tannin/cetyltrimethylammonium bromide (PPy/TA/CTAB) nanocomposite and central composite rotatable design (CCRD) was employed for the optimization of conditions. Chemical polymerization of the PPy/TA in the presence of a cationic surfactant, CTAB, reduced the particle size of composite and a rod-like structure with a lumpy surface and high porosity was observed for nanocomposite justifying the highest current response for the modified electrode. Amperometry and differential pulse voltammetry analyses were applied for all electrochemical measurements and DA detection in the range of 0.5–100 μM. The good adhesion of nanocomposite on the electrode surface, as well as porosity and high surface area of the modified electrode, enhanced the diffusion of DA molecules inside the matrix. Amperometry analysis of the Screen printed carbon electrode/PPy/TA/CTAB modified electrode displayed a good sensitivity of 0.039 μA (μM)−1 toward DA with the limit of detection of 2.9 × 10–7 M. The modified biosensor also excludes the interfering species of ascorbic acid and uric acid which makes this sensor appropriate for DA determination. The proposed biosensor showed an acceptable reproducibility and repeatability with low relative standard deviations of 4.8% and 4.4%, respectively.  相似文献   
76.
Journal of Thermal Analysis and Calorimetry - The design and manufacture of highly efficient evaporators and heat exchangers in cooling machinery need an accurate estimation of the boiling heat...  相似文献   
77.
This work deals with a reliability assessment of springback problem during the sheet metal forming process. The effects of operative parameters and material properties, blank holder force and plastic prestrain, on springback are investigated. A generic reliability approach was developed to control springback. Subsequently, the Monte Carlo simulation technique in conjunction with the Latin hypercube sampling method was adopted to study the probabilistic springback. Finite element method based on implicit/explicit algorithms was used to model the springback problem. The proposed constitutive law for sheet metal takes into account the adaptation of plastic parameters of the hardening law for each prestrain level considered. Rackwitz-Fiessler algorithm is used to find reliability properties from response surfaces of chosen springback geometrical parameters. The obtained results were analyzed using a multi-state limit reliability functions based on geometry compensations.  相似文献   
78.
A set S of vertices in a graph G is an independent dominating set of G if S is an independent set and every vertex not in S is adjacent to a vertex in S. The independent domination number, i(G), of G is the minimum cardinality of an independent dominating set. In this paper, we extend the work of Henning, Löwenstein, and Rautenbach (2014) who proved that if G is a bipartite, cubic graph of order n and of girth at least 6, then i(G)411n. We show that the bipartite condition can be relaxed, and prove that if G is a cubic graph of order n and of girth at least 6, then i(G)411n.  相似文献   
79.
80.
The problem addressed is the exact determination of the operator norm and lower bound of four-dimensional generalized Hausdorff matrices on the double sequence spaces Lp.A Hardy type formulae is found as an exact value for their operator norm and a Copson type formulae is established as a lower estimate for their lower bound.Further,exact values are found for the operator norm and lower bound of the transpose of generalized Hausdorff matrices.  相似文献   
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