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101.
Cyclic peptides capable of activating the erythropoietin receptor (EPOR) were isolated from phage display libraries by screening with a novel EPOR-IgG fusion protein reagent. A parental clone ERB1 (EPO Receptor Binder 1) was first isolated from a phage display library displaying 38 random amino acids as an N-terminal fusion with the M13 minor capsid protein, pill. An evolved library was then produced from the parental sequence using an oligonucleotide saturation mutagenesis strategy which yielded EPOR binding sequences with 20 times the relative affinity of ERB1. Two synthetic peptides were constructed from these sequences both of which bind the EPO receptor in specific ELISA, and act as full agonists in EPO dependent cell proliferation assays. These peptides are 18 amino acids in length, disulfide-bonded, and have a minimum consensus sequence of CXXGWVGXCXXW, where X represents positions tolerant of several amino acids.  相似文献   
102.
The paper presents a method of constructing, by successive approximation, stabilized approximate solutions of certain integral equations of first kind in contact problems of elasticity. In these equations, the unknown function is a surface stress under the stamp, which is allowed to have a square root singularity under the edges of the stamp, and is therefore not square integrable. The author shows that it is nevertheless possible to apply the theory of positive operators to the present problem by constructing an appropriate L2-space which includes functions with square root singularities.
Résumé On présente une méthode d'élaboration par approximations successives de solutions approchées stables de certaines équations intégrales du premier genre relatives à des problèmes de contact élastique. Dans ces équations, la fonction inconnue est une contrainte de surface sous le point de contact, qui peut présenter une singularité d'ordre 1/2 sous les bords du poin¢on, et qui dès lors n'est pas intégrable par voie quadratique.L'auteur montre qu'il est néanmoins possible d'appliquer la théorie des opérateurs positifs à un tel problème, en construisant un espace de Hilbert incluant des fonctions présentant des singularités d'ordre 1/2.
  相似文献   
103.
The system was studied by DTA, X-ray diffraction and in particular by the Guinier-Lenné method. Eight intermediate phases are described. 1) Three solid solutions in the Ga2S3 region : a) a wurtzite-type solid solution (T > 1000° C ; 0.05 < n < 0.23) (n = Fe atFe at+Ga at), b) a blende-type solid solution (700°C < T < 980°C ; 0.10 < n < 0.20) with many stacking faults, c) a non-stoichiometric hexagonal phase α'Ga2S3 type (T < 700°C, 0.07 < n < 0.12). 2) for n = 0.20 and T = 540°C a superstructure of orthorhombic wurtzite-like array FeGa4S7. 3) From n = 0.20 through n = 0.27, a non stoichiometric superstructure of tetragonal-like array has the CdGa2S4 type (600°C < T < 1030°C). 4) For n = 0.33, the FeGa2S4 has two forms depending from the temperature : a) a low temperature form is trigonal ; b) a high temperature form is orthorhombic type ZnAl2S4. Transition temperature is 1010°C. 5) For n = 0.50, Fe2Ga2S5 polytypes : a) Fe2Ga2S5α 1T type Mn2Ga2S5 ; b) Fe2Ga2S5 2H ; c) Fe2Ga2S5 3R type Mn2Al2Se5. A phase diagram is proposed.  相似文献   
104.
105.
Polyethers have been prepared by solution polycondensation of bisphenol A with an aromatic or an aliphatic dichloride, using phase transfer catalysis method.  相似文献   
106.
Hydraulic systems play an important role in modern industry for the reason that hydraulic actuator systems have many advantages over other technologies with electric motors, as they possess high durability and the ability to produce large forces at high speeds. Therefore, the hydraulic actuator has a wide range of application fields such as hydraulic punching, riveting, pressing machines, and molding technology, where controlled forces or pressures with high accuracy and fast response are the most significant demands. Consequently, many hybrid actuator models have been developed for studying how to control forces or pressures with best results.This paper presents a kind of hydraulic load simulator for conducting performance and stability testing related to the force control problem of hydraulic hybrid systems. In the dynamic loading process, perturbation decreases control performance such as stability, frequency response, and loading sensitivity decreasing or bad. In order to improve the control quality of the loading system while eliminating or reducing the disturbance, a grey prediction model combined with a fuzzy PID controller is suggested. Furthermore, fuzzy controllers and a tuning algorithm are used to change the grey step size in order to improve the control quality. The grey prediction compensator can improve the system settle time and overshoot problems. Simulations and experiments on the hydraulic load simulator are carried out to evaluate the effectiveness of the proposed control method when applied to hydraulic systems with various external disturbances encountered in real working conditions.  相似文献   
107.
新型红砖GRC复合板幕墙设计介绍   总被引:2,自引:1,他引:1  
董格林 《门窗》2009,(6):8-10
本文介绍了一种新型红砖GRC复合板幕墙的结构构造、施工要点和试验检验方案,供同类工程参考。  相似文献   
108.
Journal of Mechanical Science and Technology - Understanding nanoscale fluidic transport becomes increasingly important due to the rapid development of nanotechnology and nanofabrication. By using...  相似文献   
109.
Abstract: Available data for cholesterol content of beef, pork, poultry, and processed meat products were reported. Although the cholesterol concentration in meat and poultry can be influenced by various factors, effects of animal species, muscle fiber type, and muscle fat content are focused on in this review. Oxidative red muscles tend to have greater total lipid and cholesterol contents, although differences in the same types of muscles or cuts have been reported. Moreover, contradictory results among various studies suggest that unless there are pronounced changes in muscle structure and composition, cholesterol content is unlikely to be affected. Second, multiple issues in cholesterol analysis, including sample preparation, detection, and quantification, were evaluated. Cholesterol content of meat and poultry has been determined mostly by colorimetry and chromatography, although the latter has become predominant because of technological advances and method performance. Direct saponification has been the preferred method for hydrolyzing samples because of cost‐ and time‐effectiveness. The extraction solvent varies, but toluene seems to provide sufficient recovery in a single extraction, although the possible formation of an emulsion associated with using toluene requires experience in postsaponification manipulation. The most commonly used internal standard is 5α‐cholestane, although its behavior is not identical to that of cholesterol. Cholesterol can be analyzed routinely by gas chromatography (GC)‐flame ionization detector without derivatization; however, other methods, especially high‐performance liquid chromatography (HPLC) coupled with different detectors, can also be used. For research purposes, HPLC‐ultraviolet/Visible/photodiode array detector with nondestructiveness is preferred, especially when cholesterol must be separated from other coexisting compounds such as tocopherols. More advanced methods, such as GC/HPLC‐isotope dilution/mass spectrometry, are primarily used for quality control purposes.  相似文献   
110.
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