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The elements of the French food safety labeling system include specialized management organizations, diversified use objects and diversified identification types. Its text characteristics are reflected in the establishment of a diversified system and standard system, the construction of the cooperation mechanism between the government and market entities, and the attention to the standardized construction of special food safety labeling.In this regard, China's food safety labeling system can be optimized and constructed from the dimensions of improving the diversified food labeling standard system based on Article 71 of the Food Safety Law, building a self-regulatory management standard system with supermarkets and agricultural products markets as the core, and adding a special labeling standard system and mechanism for special food safety.

In order to solve the phenomenon of the severely uneven vibration magnitude which is transferred by the test fixture to the Specimen and reduce the deviation of the acceleration rms value, according to the electric vibration table multi--point control principle and the characteristics of a fixture frequency response, a fixture design optimization model was established. Taking a specimen fixture design as an example, the fixture FRF value was calculated by Nastran software, then the optimal design parameters of fixture was obtained according to the optimization model previously mentioned. Optimization results indicated that the mean square deviation of response acceleration and the acceleration rms variation range obtained the optimization method are all significantly smaller then that with the traditional method, while the vibration test results show that the variation range of the acceleration rms measured on the transfer point in the vibration test is basically the same with the result coming form the optimization calculation. It was proved that the proposed optimization method is feasible and practical, and it can provide a practical and theoretical guidance for fixture design in environmental vibration test. [ABSTRACT FROM AUTHOR]

Undergraduate teaching reform is in progress in Department of Electronic Engineering, Tsinghua University. With establishing a new curriculum framework, much more effort is making to strengthen the practice teaching. Electromagnetic field and microwave technology, which is an important discipline in Electronic and Information Science category, has its complete theoretical knowledge framework. Based on this framework, teachers in the Electromagnetic Fields and Microwave Laboratory are exploring actively and practicing continuously to construct a perfect, hierarchical and open experimental teaching system. The system includes three courses, covering the subjects of basic type, study type and inquiry type. The projects guide the students to explore the knowledge and its development for diferent levels of students. The dominant position of students and student-teacher interaction are emphasized to establish the learning mode under the teachers ' guidance. The teaching methods are bringing more emphasis on basic skiils, comprehensive and creative ability, cooperating and promoting with each other between teachers doing practice teaching and theoretical teaching, transforming the achievements in advanced scientific research into experimental teaching. [ABSTRACT FROM AUTHOR]

Convey tunnel is widely used in water diversion projects. It is necessary to consider the seismic resistant behavior of convey tunnel in the processes of design and construction. The analytical solutions of three-dimensional seismic response of water- filled convey tunnel induced by P waves are obtained by using the Fourier-Bessel series expansion method. According to the calculation results of an example, the influence on seismic response of convey tunnel caused by the changes of incident wave characteistic and lining material parameters is investigated. The results show that the dynamic stresses of convey tunnel lining are proportional to the incident wave amplitude, and their distributions and amplitudes are influenced remarkably by the frequency and two propagation angles of incident P waves. Furthermore, the higher the strength of convey tunnel lining concrete is, the smaller dynamic water pressure and the greater dynamic circumferential and axial stresses will be. [ABSTRACT FROM AUTHOR]

To overcome the drawback of small displacement, large pressure fluctuation and unbalanced radial force of a rotary positive displacement pump, the rotating-guide-bar and gear mechanisms assembled driving systems of differential velocity vane pump with the cranks and the guide-bars as active parts are presented in this paper. With variation of the motion characteristic coefficient on the rotating-guide-bar and gear mechanisms assembled driving systems, their motion characteristics and laws are investigated. The basic parameter equations are established and the kinematics characteristics and mechanics performance are analyzed for these two types of driving systems. The results show that the transmission performance of rotating-guide-bar and gear mechanisms assembled driving system with the guide-bars as active parts is superior to that with Cranks as active parts. [ABSTRACT FROM AUTHOR]

This paper presents an improved adaptive simulated annealing genetic algorithms of optimal sensor placement (OSP) based on Modal Assurance Criterion (MAC). Taking the maximum off-diagonal element of the MAC matrix as a target function and the sensor number as a constraint condition, a dualistic coding genetic algorithm is developed which improve the traditional simulation annealing algorithms and use it as an independent operator of GA. Therefore, adaptive crossover and mutation probabilities are adopted to prevent premature convergence. Example results clearly indicate that the method is feasible in optimal sensor placement and number selection, and optimal placement for different accuracy requirement is obtained. [ABSTRACT FROM AUTHOR]

Objective: To make an epidemiological investigation on clonorchiasis sinensis and relevant factors in the south of Hunan Province., Methods: One village from each of Lengshuitan District and Qiyang County was selected for the survey from November to December in 2006. Stool samples from villagers were collected and examined by modified Kato-Katz method. Questionnairing was performed for relevant knowledge and attitude among residents. The infection rate in animal reservoirs and intermediate hosts were detected., Results: A total of 586 cases with Clonorchis sinensis infection were found from 777 people with a prevalence of 75.4%. The average egg density was 451 eggs per gram (EPG) feces. Light, moderate and heavy infections occupied 85.5% (501/586), 14.0% (82/586), and 0.5% (3/586) respectively. Prevalence in males and females was 76.9% (316/411) and 73.8% (270/366) respectively with no significant difference (chi2 = 1.013, P > 0.05). Infections were found in all age groups, with the highest prevalence in the group of 70 to 79 years (85.7%, 30/35). By occupations, the prevalence was 82.5% (447/542) in peasants, 79.3% (42/53) in doctors, 73.7% (28/38) in teachers, and 73.5% (25/34) in local cadres. The infection rate was 17.4% (29/167) and 7.4% (2/27) in Parafossarulus seriatulus and Alocinma longicornis, and 69.2% (9/13) and 5.3% (1/19) in Carassius auratus and Cyprinus carpios respectively. Adult worms were found in all 3 dogs dissected. Over 80% inhabitants did not know that this disease can be acquired by eating raw fish. 95.6% (153/160) of the farmers and 56.7% (349/616) of the students had a history of eating raw fish. The water was contaminated with C. sinensis eggs by using untreated feces as fertilizer for farming and by scrubbing pail latrines in the ponds., Conclusion: The prevalence of clonorchiasis in human population is high in Lengshuitan District and Qiyang County of Hunan Province. Eating raw fish and using untreated feces as fertilizer are the most important epidemiological factors of the disease.

A series of batch tests were conducted to investigate the effects of initial pH on bio-hydrogen production from acid pretreated municipal sludge. The pH of sludge was first adjusted to 2.0, 3.0, 4.0 and 5.0, stood by for 24 h in a refrigerator at 4 degrees C, then adjusted to pH 2.0-12.0 respectively before using as the substrates for batch experiments. The results showed that the acid pretreated sludge with initial pH 11.0 gave the highest hydrogen production, and the corresponding accumulative hydrogen for sludge (dry basis) pretreated at pH 2.0, 3.0, 4.0 and 5.0 were 0.59, 1.83, 0.50 and 0.56 mL/g respectively. Hence, it could be seen that the initial pH 11.0 for the acid pretreated sludge should be the optimum pH range for promoting the growth of dominant hydrogen-producing anaerobes, while inhibiting hydrogen-consuming anaerobes. Meanwhile it also could be concluded that both hydrogenogen and methanogen were inhibited at the initial pH 2.0 to 4.0 and 12.0, which resulted in a low hydrogen production. Although the hydrogenogen and methanogen could be promoted at the initial pH 5.0 to 9.0, the corresponding hydrogen production was still quite low.

Objective: To present a new neurovascular island flap for fingertip reconstruction., Methods: Based on the transverse palmar branch of the digital artery, this flap was designed on the volar side of a digit and reversed to repair the fingertip defects., Results: 12 fingers in 11 patients were reconstructed using this flap. Of them, 11 flaps survived and one necrosed. The contour of the reconstructed fingers looked well., Conclusion: This new neurovascular island flap provides excellent padding and sensation for fingertip reconstruction. The technique is simple.

Objective: To investigate the inhibitory action of phytoestrogen soybean isoflavone on body weight increasing in ovariectomized rats that imitated postmenopausal women and the effect of decreasing food availability., Methods: Four-month-old Wistar rats were sham-operated or ovariectomized by abdominal cavity operation and divided into Sham, Ovx, estrogen group(EC) and three isoflavone group and feed 16 weeks. The diet was prepared by ourselves and some contained diethylstilbestrol or different concentration of isoflavone. During the experiment, the rats weight and food intake were recorded. The food utilization rates of each group were calculated., Results: The result showed that high dosage of soybean isoflavone (187.4 mg/kg bw x d) can significantly inhibited OVX induced weight gain and inhibitory action decreased with the dose reduce. Compared with Sham and Ovx group, the food intake of isoflavone group decreased significantly but no different in 3 dosage group and higher than EC group. Compared with Ovx group, the food utilization rates of high isoflavone group decreased significantly but higher than EC group. Isoflavone not influenced the growth and organ/body rates of rats., Conclusion: High dosage of isoflavone (187.4mg/kg bw x d) decreased OVX rat's weight gain significantly through reducing food utilization rate.

Objective: To investigate the effect and its mechanism of salmon milt DNA (SMD) on age-related involutions in mouse thymus., Methods: Female BALB/C mice aged 10 months were divided randomly into three groups according to their weights. They were high dosage group (333.33 mg.kg(-1).b.w.d(-1)), low dosage group (166.67 mg.kg(-1).b.w.d(-1)) and control group (0 mg.kg(-1).b.w.d(-1)). After five weeks, their thymus indexes were measured and the thymocytes were counted and the thymus cortex thicknesses were also measured using Image-Pro Plus (version. 4.0) software in the thymus section. All the data were analyzed by SAS statistic software. Microarray technique was applied to screen the gene fragments, which were differentially expressed between the high dosage group and the control group, together with RT-PCR to further confirm some of them., Results: No significant differences of the variables including body weight, thymus weight and thymus indexes among the three groups were found. The thymocytes quantities of thymus cortex and medulla in the high dosage group were significantly higher than those of the control group (P < 0.01 and P < 0.05, respectively). The thymus cortex thicknesses of both SMD supplement groups were significantly higher than that of the control group (P < 0.01 and P < 0.05 respectively). 112 differently expressed gene fragments were isolated. Furthermore, we found the fragments with the logged number of U23789, X80232 and Aw209102 were highly expressed in the high dosage group when RT-PCR technique was used., Conclusions: SMD may reverse the age-related involutions in mouse thymus via up-regulation the expression of proliferation related genes and via up-regulation the expression of development and differentiation related genes simultaneously.