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Flavivirus protease has been deemed a potential target for drug and therapeutics development due to its crucial role in viral replication. In this study we prepared a monoclonal antibody (mAb) against nonstructural protein 3 (NS3) protease portion of Japanese encephalitis virus (JEV), and evaluated its inhibitory effect for NS3 protease activity. First, a JEV NS3 protease-specific mAb (designated 2C2) was generated by the traditional cell fusion technique. Second, the binding specificity of 2C2 for NS3 protease was determined by indirect fluorescent assay and Western blotting. Finally, inhibitory effect of 2C2 for NS3 protease cleaving human stimulator of interferon gene was evaluated. Therefore, mAb 2C2 provides a potential diagnostic tool for differential diagnosis for patients who have been vaccinated with inactivated vaccine or naturally infected, and might be genetically reconstructed and optimized for new therapeutics development.

In order to reduce the adhesion of moist threshed rape mixture and cleaning sieve, a method named “Hot-airflow Cleaning” has been proposed. Firstly, the key factors influencing anti-adhesion property were obtained based on the theoretical analysis. They were temperature, wind speed and fan inclination. Then, based on the single-factor experiments, the proper temperature of the fan was 30-50oC, the proper wind speed and inclination of the fan were 2-4 m/s and 15-45°, respectively. Finally, the fan’s parameters were optimized by Box-Behnken design. The results showed that the optimum technological parameters were temperature of 50 oC, a wind speed of 4 m/s and that fan inclination was 45°. This research could provide a reference for the improvement of cleaning system for rape combine harvesters.

In order to study the influence of the side drive on the balance state of the threshing drum, this paper used the side eccentric load chain drive as the power on the threshing drum dynamic balance test bench. By analyzing the influence of different radial phases, different axial distances, and spiral combinations of the threshing drum on the counterweight, this paper studies the law of the effect of side partial load chain drive on the dynamic balance of the threshing drum and finds that the side chain drive has obvious influence on the unbalance phase of the threshing drum and the change of the axial distance of unbalance has little effect on the equilibrium state of the threshing drum. And from this, a vibration balance method based on the equivalent unbalance of the chain drive is proposed, which can predict and calculate the unbalance of the threshing drum. The unbalance of the threshing drum predicted by this method is smaller than the actual measured unbalance. The maximum error is 32.64% and the minimum error is 4.6%. In the two tests, the predicted unbalance is 1.24 mm/s in amplitude and 270 degrees in phase and amplitude 1.4 mm/s and phase 120 degrees, respectively. The measured unbalance is amplitude 1.587 mm/s and phases 286 degrees. The error between prediction and actual measurement is less than 32.64%, and the unbalance amplitudes that can be reduced by one-time dynamic balance are 0.856 mm/s and 0.674 mm/s, respectively. The research results in this paper provide an effective method for the balance state of the multidrum side chain transmission.

Harvesting main crop rice with a wide header at a required height can increase its ratoon crop yield by decreasing the stubble rolling rate. However, an increased harvest width brings in more input material in a specific time, causing the size enlargement or working speed slowdown of harvesters. To solve this issue, a double-cutterbar structure was proposed. To provide a design baseline for the structure, the cutterbar configuration methods based on rice plant deformation were developed and verified, stalk shearing tests were conducted, and a double-cutterbar prototype was fabricated and tested. The results indicated that the methods developed for the configuration of the upper and lower cutterbars could considerably implement their functions of lowering the straw-grain ratio and keeping stubble height as required. The shearing tests indicated that the bevel angle significantly influenced the total shearing energy on each cutting point in Internode 2 and 3 (p &lt, 0.05) due to the increased stalk cross sectional area. The stubble rolling rate, panicle straw length and stubble height of the developed harvester were 26.9 %, 125 &plusmn, 80 mm and 332 &plusmn, 22 mm, respectively, which could meet the requirements of main crop rice harvesting. The outcomes indicated the functionality and practicability of the double-cutterbar structure developed based on rice plant deformation and shearing properties.

Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (Rh ) in warming experiments. Warming is expected to initially increase Rh but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on Rh . However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two-step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on Rh . Soil samples from three Tibetan ecosystems-an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)-were exposed to a temperature gradient of 5-25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in Rh by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater Rh decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to Rh in Tibetan alpine soils-especially in copiotrophic soils-will be weakened by microbial community responses under short-term warming.

The main working parts of the cleaning device of a rice combine harvester can be controlled by an established control strategy in real time based on the monitored grain sieve loss. This is an efficient way to improve their cleaning adaptability, since as a consequence, the main working parameters of combine harvesters can automatically adapt to crop and environment changes, and the corresponding cleaning performance can be improved. To achieve the target of cleaning control based on the monitored grain sieve loss, a fuzzy control system was developed, which selected S7-1200 PLC as the main control unit to build the lower computer hardware system, utilized ladder language to complete the system compilation, and used LabVIEW 14.0 software to design the host&ndash, computer interface. The effects of fan speed, guide plate angle, and sieve opening on the grain sieve loss and grain impurity ratio have been investigated through a large number of bench tests. The relevance level of the operating parameters on the performance parameters has been determined also, and finally, a fuzzy control model was developed for the cleaning system. The experiment results indicated that the designed fuzzy control model can control the cleaning section settings, such as fan speed and guide plate angle automatically, and reduce the grain sieve loss to some extent.

In order to solve the problems of deformation caused by traditional threshing rack applied to the variable-diameter cylinder, two high-strength threshing racks (truss-type threshing rack, reinforced plate-type threshing rack) were designed. Through statics quantitative analysis on the basis of theoretical analysis and finite element analysis and calculation conducted on the rigidity and strength characteristics of traditional threshing racks, truss threshing racks and reinforced plate threshing racks, it shows that the reinforced plate threshing rack with higher strength, simpler structure and lighter weight is more suitable for the operation requirements of variable diameter cylinders.

In agriculture, the body tilt of vehicles or platforms can be controlled by levelling technology to prevent rollover and improve efficiency when operated in rough terrain. Many researchers have carried out important study in this area based on mechanism development and optimization, but most of them are not effective to crawler vehicles. The objective of this research was to specifically develop a levelling mechanism for crawler combine harvester, since as a consequence, enhancing the operation performance and trafficability. This levelling method depends on a hydraulic four-point adjustable lifting chassis, which could adjust vehicle chassis by controlling hydraulic cylinders. Therefore, the mathematical models between chassis attitude (including ground clearance, the horizontal and longitudinal inclination angle) and each length of hydraulic cylinder were deduced. The principle of lifting mechanism of crawler vehicle chassis was analyzed by using virtual prototyping software ADAMS, as well as dynamic performance under three different attitude adjustment conditions. The maximum adjustment range of the ground clearance is 140 mm and the lateral inclination adjustment range is ±5.17°. Experiment showed that the designed levelling mechanism was feasible and with positive significance for crawler vehicles levelling.

Rationale: Carney complex (CNC) is a multiple neoplasia syndrome with autosomal dominant inheritance. CNC is characterized by the presence of myxomas, spotty skin pigmentation, and endocrine overactivity. No direct correlation has been established between disease-causing mutations and phenotype. Patient concerns: A 16-year-old boy was admitted because of excessive weight gain over 3 years and purple striae for 1 year. Physical examination revealed Cushingoid features and spotty skin pigmentation on his face, lip, and sclera. Diagnoses: The patient was diagnosed as Carney complex. Interventions: the patient underwent right adrenalectomy and partial adrenalectomy of the left adrenal gland. Outcome: Results of imaging showed bilateral adrenal nodular hyperplasia, multiple microcalcifications of the bilateral testes, and compression fracture of the thoracolumbar spine. Histopathological results confirmed multiple pigmented nodules in the adrenal glands. DNA sequencing revealed a nonsense mutation in the gene encoding regulatory subunit type 1-alpha of protein kinase A (PRKAR1A; c.205C > T). After the second adrenalectomy, the Cushingoid features disappeared, and cortisol levels returned to normal. Lessons: Carney complex is a rare disease that lacks consistent genotype–phenotype correlations. Our patient, who carried a germline PRKAR1A nonsense mutation (c.205C > T), clinical features included spotty skin pigmentation, osteoporosis, and primary pigmented nodular adrenal disease. Adrenalectomy is the preferred treatment for Cushing syndrome due to primary pigmented nodular adrenal disease.

This paper deals with the numerical calculation method of deflection deformation of rice stalks. Due to large deflection of rice stalks caused by reel operation, it is improper to adopt the conventional formula that is usually used in small deflection calculation to fit rice stalk deformation curves. Therefore, a large deflection calculation formula in combination with Simpson&rsquo, s formula was utilized to compute flexural rigidity (EI) and to fit curves. The experiments were conducted under different loads (0.03, 0.04, 0.05, 0.06, and 0.07 N) on a self-established deflection testing rig to verify this method. As a result, the measured results corresponded considerably to ones predicted by this method, furthermore, the flexural rigidity was maintained at a stable level under different loads. This study can provide the basis for establishing a complete deformation model of rice plant and can also be applied in deflection calculation of other stalk crops.

A triaxial ellipsoidal particle model was established according to the physical properties of rice seed, and its impact behaviour against a grain loss sensor was simulated using the discrete element method (DEM). The contact criterion was developed directly by solving the intersection equations, and the contact forces were calculated according to elastic–plastic and Mindlin models. It was shown that the seeds may perform translational and rotational motion in a 3D space after the impact. With the influences of particle shape, orientation and angle of incidence, three typical impact processes were found: single impact, multiple impacts in a short-time, and continuous impacts. Two important parameters for the design of loss sensors are the maximum normal impact force Fn max and the force rise-time tr. Simulations showed that an increase in particle ellipticity strongly enlarged the differences in Fn max. As the ellipticities increased from unity to 2, the defined force ratio η decreased from 100% to about 40%, and this value decreased to less than 20% when ellipticities continuously increased from 2 to 4. Tangential velocity led to an asymmetric variation of η. tr was generally distributed between 12 and 54 μs. In laboratory tests, rice seeds were allowed to free fall onto a loss sensor from a height of 320 mm. Results indicated that the peak output voltage was fluctuated in 1.5–4.5 V, and the rise-time was in 14–48 μs.

Impact damage is the main form of rice threshing and it is also a significant cause of rice injury. Based on contact mechanics, models of the compressed displacement and the largest pressure distribution were established for the case when the threshing tooth obliquely impacts against the rice kernel. A critical velocity formula for impact damage was developed. A computer-aided design model of a rice kernel comprising of three layered ellipsoids was established. HyperMesh software was used to partition mesh elements and to set material and contact parameters for each element, constructing a finite element model for the analysis. Using LS-DYNA software, the impact between the threshing tooth and the rice kernel was simulated and analysed. The simulation showed that the rice husk was subjected to tensile stresses. Tensile stress was a maximum at the front of the contact zone and shifted continuously. The entire kernel rolled during impact. The critical damage velocity for the kernel, corresponding to the critical von Mises stress was 29.5 m s−1, which was in agreement with experimental results.

The performance of a vacuum-cylinder seeder for the precision sowing of rape seeds was investigated. For releasing seeds from nozzles smoothly, a positive differential pressure was applied to the seed. The forces acting on the seeds in free flight were calculated using the computational fluid dynamics (CFD) software Fluent. Using the differential equation for seed motion, seeds falling trajectories using different working parameters were numerically determined. A high-speed camera system mounted on a laboratory seeder test-rig was used to record the motion of seeds. A mean shift algorithm for tracking seeds was used. The horizontal displacement x and the fall time t f of seeds predicted by the numerical analysis and measured by the high-speed camera system were compared. The results indicated that the relative errors of x and t f were Based on the analysis of seeds falling trajectories, it was found that the variations of positive differential pressure Δ p and release angle θ had significant effects on seeding uniformity. In order to analyse their effects on horizontal displacement, a coefficient of positive differential pressure variation χ p and coefficient of sowing angle variation χ θ were proposed and their values calculated. Calculations indicated that the optimum levels for Δ p and θ for the precision seeding of rape seeds were in the range of 1–2 kPa and from −10 to 0°, respectively. Experiments were carried out on the vacuum-cylinder precision seeder test-rig and the results showed that the average seed spacing interval error reached the minimum at Δ p = 1.5 kPa and θ = −5° and that the error increased almost linearly with increasing of cylinder rotational speed.

The giant magneto-impedance (GMI) effect was observed in almost zero-magnetostrictive Co 66.3 Fe 3.7 Si 12 B 18 amorphous ribbon toroidal cores after annealed by a 25 A/mm 2 pulse current density under a transverse magnetic field of 2 kA/m for 30 s. A maximum GMI ratio of 34% and a sensitivity of about 65%/Oe were measured employing a 900 kHz sharp pulse current generated by a CMOS inverter multivibrator. A sensitive non-contact type current sensor composed of an amorphous ribbon toroidal core connected with a pulse current generator, a peak detector, and a differential amplifier is presented. The sensor is able to examine the value and direction of dc current. The measurement accuracy of 0.45% and sensitivity of 0.67 V/A were obtained with full scale ±2.5 A using a power source voltage of 5 V.

"Central Government Allocates a Special Fund of 2.4 Billion RMB to Provide Focused Support for the Project: The State Education Commission and the Ministry of Finance Convene a National Conference to Plan the Implementation of the Program"

In this paper, the author puts forward a new adhesion properties test method, which define the adhesion rate by the residual adhesion area to measure interface adhesion properties when the traditional method measured by adhesive force cannot work. The residual adhesion area was calculated by matlab language with image technology. Adhesion properties test of the interface between rape mixture materials and screen matrix was carried out to help illuminate this new test method. The results show that the adhesion rate of the interface between rape mixture materials and screen matrix was 9.5% with error less than 2%. It is also show that this method can be used to test adhesion properties effectively.

Flexural mechanical properties of four kinds of corn stalks were studied on the WDW-300 type micro-control electronic universal material test machine. The load- deformation curves of corn stalks and the maximum load, elastic modulus, flexural strength and deformation value were obtained in the way of 3-point bending. The influence of varieties, cross-sectional area, growth areas and moisture content on the mechanical properties of corn stalks was analyzed. The result that the bending process can be made of linear elastic process, non-linear elastic process and bending fracture process was got. The average anti-flexural strength and elastic modulus of corn stalks are 7.85MPa and 0.15GPa. Differences of Linear elastic range and deformation value of stalks bending exist in the varieties. Under other condition of the same, a positive correlation linear relationship was founded between the maximum load and cross-sectional area of corn stalks. With the increasing of growth areas, the maximum load was decreased gradually. Test result has important guiding significance to the design of high efficiency and low energy consumption corn harvester.

Bionic desorption & damp-tiny material screening technology has been widely used in the industrial and agricultural production, which has not been yet used in cleaning part of Combine Harvester. Current situation in research and application of bionic desorption & damp-tiny material screening technology was introduced in this paper. Similarities and differences between these studies and the urgent problem of rape excursion materials' adhesion with cleaning screen which block hole and lead to an increasing cleaning loss were analyzed and potential application in rape cleaning of the bionic desorption & damp-tiny material screening technology was prospected. Primary design principles of bionic nonsmooth surface cleaning screen were indicated in this paper. Implication feasibility of bionic desorption technology in rape cleaning was preliminarily proved by the comparison test in field between trail produced bionic nonsmooth surface screen and common screen. Suggestions of further implication research of bionic desorption & damp-tiny material screening technology in rape cleaning were given.

On the basis of analyzing disadvantages of conventional prediction model of air-and-screen cleaning device, a new regression model based on support vector machine was proposed to predict and control of cleaning process precisely. Parameters of e-SVR models were determined utilizing non-heuristic Grid Search, heuristic GA and PSO which could avoid the choice of randomness. The effect of samples in different on prediction performance of e- SVR was analyzed compared with BP. The results indicate that the prediction property of e-SVR is better than BP especially in small-sample.

The input gears from the first stage of a combine harvester gearbox have been subjected to experimental testing. A three-dimensional finite element model was established by using Solid Works and the effect of an external load distribution along the gear tooth width was added according to actual working situations. In the Solid Works/Simulation module, the contact relation was established based on the real assembly relations, and to calculate Von Mises stress, on the teeth. Through modal analysis, the gears teeth frequency was analyzed contrastively with the inherent model of the transmission and analyzed the influence of them. The experiment was carried out in the self-made gearbox fatigue test bed. The results indicate that serious pitting appeared on the surface of the teeth when the working time was over 500 hours and the input gears were not measurably distorted, which basically coincides with the analyzed results of the theory.

Damage is easy to occur during the process of harvesting, classification, packaging, transporting, processing, preservation and selling etc. and the detection of internal damage is a difficult problem. Rice kernels were classified as those with none, single, double or multiple stress cracks. An image processing algorithm was used to enhance the object and reduce noise in the acquired image. At the same time a machine -vision system was developed to detect different types of stress cracks in rice kernels. None and single stress cracks were the easiest to detect. Careful positioning of the kernel over the lighting aperture was necessary for accurate detection of double and multiple stress cracks. This system provided an average accuracy of approximately 96.5% to none crack, 93.4% to single crack, 84.2%to double cracks and 83.4% to multiple cracks compared to human inspection. The processing time was between 0.45 and 0.12 s/kernel.