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- Abstract：The surface topographies of transferrin films before and after adding a receptor were measured by the atomic force microscope and analyzed by simple fractal analysis and multi-fractal spectrum. The combination of transferrin and its receptor was also in the light of fractal analysis. The results indicated that the multi-fractal dimensions could describe the transferrin surface geometry features and the uniformity of surface comparative height distribution well. After the combination of transferrin and its receptor, the surface appearance turned to smoothness and the degree of combination was better in central than that on the boundary.Keywords：transferring,multi-fractal,atomic force microscope(AFM),FIPS22|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：An axisymmetric parenchyma fluid-filled spherical cell model was developed to study mechanical behavior of a single plant cell.The model consisted of an elastic soft thin wall enclosing incompressible liquid.The wall was assumed to be an incompressible super-elastic thin membrane with penetrability for inside fluid.The constitutive relation of the wall was chosen as Moony strain-energy function.The osmosis rate was assumed proportional to the cell turgor.The cell was compressed by two parallel rigid planes.The control equations were built using large deformation geometric relationship,and the solutions were obtained by numerical method.Using this model,principle stretch ratios and tensions in the wall,deformations of the cell and relationship between turgor and compressive force were obtained.It was found that the rigidity of plant cell increased nonlinearly with the cell's deformation.Furthermore,the osmosis made the cell relax under constant compressive deformation.1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The ratio method of dual fluorescent emissions of chemical pH probe BCECF AM with single excitement under laser scanning confocal microscopy showed that there was a basification about 0.5 units of pH in the vacuoles of guard cells during stomatal closure that induced by ABA(open: pH 5.3,closed: pH 5.8).The pH of ectocytic saps of guard cell vacuoles were regulated by buffer of Mes/Tris at pH 5.3 or 5.8 respectively.The observations under electron microscope to negatively stained saps of guard cell vacuoles showed there was almost no effect of pH 5.3 to the dimension and distribution density of the particles from guard cell vacuoles of open stomata.However,pH 5.8 induced obvious increases in the dimension and distinct decreases in the distribution density of the particles from guard cell vacuoles of open stomata.The non-specific proteinase K could make a disappearance of the particles from the vacuoles of an open stomata.Basing on all of the above findings,We suppose that the particles from the vacuoles of an open stomata are protein.2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Endogenous abscisic acid(ABA) content,ethylene production,ACC content,activities of ACC oxidase were measured during ripening process of tomato fruit(Lycopersicon esculentum Mill.cv.Zhongza 101).Although the maximums of ABA content,ACC content and ethylene climacteric peak occurred at different ripening stages,they all increased in seeds before they increased in pericarp tissues.The maximum ABA and ACC contents preceded ethylene production in both the seeds and pericarp.Changes of the activity of ACC oxidase were coincident with that of ethylene production and ABA content.Exogenous ABA treatment increased of ABA content,both in pericarp and seed,and ethylene production,while treatment with fluridone,an inhibitor of ABA synthesis,inhibited them.The results suggest that seeds may impact the process of postharvest tomato fruit ripening by regulating of endogenous ABA content and ethylene production,and ABA regulates fruit ripening by triggering ethylene production.1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Tomato structural-functional model was set up to investigate the effect of different light environment on tomato morphology structure.To calibrate the model,multi-targets estimating method,which was based on the description of plant topological structure,was adopted to fit the field data.Two cases,i.e.no-shading and local-shaded plants were simulated by the model,and the comparative results were presented in view of the following aspects: morphology at different growth stages,cumulated biomass into organs and 3D visual output.The results indicated that no-shading plants have shorter and stronger stem internodes, bigger leaf and fruit compared with local-shaded ones.By model,the characteristics of morphology structure under different light interception were well simulated and fitted the field data very well,which verified the model was accurate.1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To solve the key problem of large resistance against and low digging rate of digging parts,A digging components design model was developed with Visual Basic 6.0 by adopting a new designing method computer aided analysis(CAA).Movement analysis,parameter optimization and performance analysis were completed. Computer simulation showed that digging rate was more than 98%,obvious rate more than 97% and damaged rate less than 4.5%.The workload of CAA was only about 50% that of the old method and precision increased.What's more,it avoided the problem that on-the-spot experiment conditions are influenced by climate,soil quality and planting habit.2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A conveying and orientating section of an apple sorter was developed aiming at the problems of confusion of stem and calyx and grading errors encountered in a common sorter equipped with computer vision system. When this mechanism is working, the apple can be oriented by the stem-calyx in vertical direction. The experiments indicated that the mechanism oriented apples succeed by 94%, took less than 4 s for each apple, and met the requirements of a online detection. After the orientation, apples move with the conveyor while the computer vision system collects and processes images. It takes less time to process images and improves the precision for no distinguish of stem-calyx defects.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Polyphenol oxidase(PPO) is one of the major factors which influence the quality of wheat flour and related products.It's very essential to understand PPO characters in improving appearance of noodle and steam bread.In this study,three methods were used to extract PPO from 21 wheat varieties and their activity were measured.The results indicated that PPO extracted from whole kernel meal by SDS(method 3) had highest activity,being up to 1.4-3.9 folds of that extracted by phosphate(method 2).The PPOextracted from intact grain by phosphate(method 1) had lowest activity 5.3-42.1 times lower than that extracted by method 3.The values of PPO activity measured by the three methods were significantly related with each other.The results of time course showed that activity curve of high PPO varietywas different from that of low PPO variety.Even for a variety,method 2 and 3 gave different PPO activity areas.It is suggested that SDS could improve PPO extraction and its activity measurement.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Micropropagated 'Fuji' apple plants were used to study the effects of water stress at different deficit intensities by regulating the osmotic potential of the solution with PEG-6000 on transport and distribution of()~(14)C-assimilates by feeding()~(14)CO_2.The quantity of exported assimilates from fed leaves was significantly reduced under water stress as compares with CK.The CK plants' export percentage of()~(14)C-assimilates of was 1.42,3.41,and 10.18 times as compared with mild stress(solutions with osmotic potential of-0.75?MPa),moderate stress(solutions with osmotic potential of-1.5?MPa), and severe stress(solutions with osmotic potential of-0.75?MPa),respectively.Most of()~(14)C-assimilates was exported from the fed leaves within 24 h after feeding()~(14)CO_2 under mild(94.22%) and moderate(93.95%) water stress,significantly higher than CK(55.65%).89.43% of labeled()~(14)C-assimilates exported from the leaves within 48 h after feeding leaves were distributed in the above-ground part of the micropropagated plants under a normal water status.About 64.78% of()~(14)C-assimilates exported from fed leaves was found in the roots on severe stress.The distribution pattern of()~(14)C-assimilates among the various organs was modified by water stress,as the competitive power for assimilates(()~(14)C-distribution coefficient,K) of the above-ground part,especially shoot apex was significantly decreased,and the sink ability of roots particularly the fine roots had a stronger power to compete for assimilates.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：persimmon,1-Methylcyclopropene(1-MCP),room temperature storage,freshness-keeping effect1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To screen out an optimal protocol with low-cost and high-efficiency for superovulation and embryo transfer(ET) in the commercial application,127 sheep of Dorset,Suffolk and Dorper breeds and 111 Boer goats were superovultated with different FSH made in different countries and the obtained embryos were transferred into 1?231 Small Tail Han sheep and milk goats with different methods(surgically or by laparoscope) under production conditions n.The results demonstrated that the mean number of viable embryos per Boer goat superovulated by FSH made in New Zealand(n=14) was higher(P<0.05 than that by FSH made in Australia(n=7.59);the superovulatory response in Boer goats treated with FSH made in China Academy of Science(CAS) and FSH made in New Zealand was similar(P>0.05);the mean numbers of viable embryos from sheep of different breeds superovulated by the same FSH or shhep of the same breed superovulated by different FSH(made by CAS or in New Zealand) showed no significante difference((P>)0.05);and no significant differece(P>0.05) was observed in the pregnancy rates of embryos transferred surgically and by laparoscope(57.44% vs 60.20%).In conclusion,the combination of superovulation with FSH(made in CAS) and ET by laparoscope could be suitable for sheep and goat ET industrialization in terms of low cost and high efficiency.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Keywords：China Experimental Minipig(CEMP),prion,gene clone,sequence analysis2|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Applying object-oriented technology, virtual human-machine interface in mechanical system was defined by interdependent classes and objects, whose attributes and services were defined and hiberarchy relationships among which were confirmed. And then the frame of virtual human-machine interface was constructed, and its object-oriented design was realized with the aid of computer. Through this method, the human-machine interface of a vehicle cab was designed as an instance. Results showed that every element of the interface could be managed easily, the relationships among elements could be expressed clearly, and the dependability, maintainability and expandability of human-machine interface were improved.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To analyze and display the contact of skew bevel involute gears,a mathematic model was established by vector gyration and coordinate transform of circle vector functions and sphere vector functions.Space figure of gears contact was drawn up by Matlab.The developed package was applied to a pair of skew bevel gears,and results indicated that the instantaneous contact lines were parallel straight lines and the transmission ratio was invariable.The package can be used not only for machining skew bevel gears on NC machine tools,but also for computer aided analysis of skew bevel gears contact.1|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A tie-line model was developed by working out feasible tie-line set based on developing main model of distribution network planning. A feasible tie-line set were developed on the base of adjacent matrix, path matrix and path sub-matrix. Example proved that the method was feasible and effective to improve the reliability of distribution network.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A tube jointing device was adopted for the contact of stock and scion to predigest the device and to reduce cost.The tube device included an automatic tube sending and cutting device and an tube grasping finger.The former device was used to send and cut the tube automatically.The latter was a symmetrical four mechanical linkage with a driving lever and a follower lever on both sides.The operator was connected with follower lever.The tube grasping finger made the tube close or open.Important parameters of grasping finger were analyzed by calculation and computer simulation.While length of driving lever,length of follower,length of finger's operator,distance between finger's two axes,distance from point of load to axis and electric magnet stoke h were 35?mm,25?mm,15?mm,6?mm,21?mm and 5?mm respectively,tube's opening wide s was 5.4?mm.The results of prototype experiments showed that the ratio of success is 97%.0|6|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
