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In order to overcome the shortcomings of the parallel mechanism used in express delivery industry， such as small motion space and limited application scope，a 2 （2-UPR+RPU） series-parallel hybrid mechanism is proposed based on the 2-UPR+RPU low-DOF parallel mechanism. The inverse position solution and workspace analysis are carried out in order to be applied in industrial production. Firstly，the hybrid mechanism is modeled in SolidWorks，and its degree of freedom is obtained by analyzing the screw theory. Then，the position inverse solution of the mechanism is solved by continuous method. Finally，the motion simulation is carried out in SolidWorks by using CAD variable geometry method and the track data of the processing points are obtained，and the workspace is obtained by using Matlab software. The workspace of 2 （2-UPR+RPU） hybrid mechanism is much larger than that of single-layer parallel mechanism，and its shape is regular and symmetrical. The 2（2-UPR+RPU） hybrid mechanism has both the flexibility of series mechanism and the high rigidity and precision of parallel mechanism. Through corresponding program control，it can replace manual work.

There are two dimensions of creative thinking: a creative “state of mind” and creative “thinking tactics”. The former means clarity of mind which makes people always ready for truth, while the latter points to an effective way of creative thinking. The formation of creative thinking requires a leisurely mindset. Leisure education could help people make the best use of their leisure, let leisure wield a positive influence on creativity cultivation, and eliminate the downside of the current education, thereby rendering people’s efforts to cultivate creative thinking more effectively. The goal of leisure education is to achieve a creative “state of mind” required for creative thinking, while the content and approaches adopted by leisure education could provide inspiration for creative “thinking tactics”. To vigorously expand leisure education will be necessary in this creative age, especially for the cultivation of creative talents.

The theory of warship fire safety engineering is the basis of damage control engineering. According to the public safety triangle and the characteristics of ship damage protection engineering, this paper proposes a theoretical framework system for ship fire safety engineering, including ship fire development, ship fire damage and ship fire protection. The progress of these three parts are summarized in such aspects as enclosed fire dynamics, open space fire dynamics, fire damage mechanisms for personnel, equipment and structures, fire smoke control, fire elimination technology and new fire extinguishing technology. By optimizing the theoretical system of warship fire safety engineering and improving fire prevention and control technology, the survivability of warships will be enhanced.

Objective: To explore the influence of hydrogen sulfide on the intestinal biological barrier, by applying exogenous hydrogen sulfide and hydrogen sulfide synthase inhibitor for the treatment of rats with severe burn injury., Methods: One hundred and four SD rats were divided into sham injury (SI, n = 8), burn control (BC, n = 32), sodium hydrosulfide (SH, n = 32), and propargylglycine groups (PPG, n = 32) according to the random number table. Rats in group SI were sham injured without fluid resuscitation. Rats in the latter 3 groups were inflicted with 30% TBSA full-thickness scald (referred to as burn below) on the back and intraperitoneally injected with 40 mL/kg balanced salt solution immediately after injury. Rats in groups SH and PPG were respectively intraperitoneally injected with SH (56 µmol/kg) and PPG (45 mg/kg) within 1 hour post injury. From post injury day (PID) 2, SH (56 µmol/kg) and PPG (45 mg/kg) were respectively intraperitoneally injected once a day to rats in groups SH and PPG. Eight rats from groups BC, SH, and PPG were sacrificed on PID 2, 7, 14 and 21, and ceca samples were collected. Ceca samples were added to the appropriate culture medium after being homogenized and diluted, for the culture of Bifidobacterium, Lactobacillus, Enterococcus, Enterobacter, and Candida albicans. The content of bacteria was calculated after the bacteria number was counted. The same procedure was performed for rats in group SI. Data were processed with logarithmic function, one-way analysis of variance, analysis of variance of factorial design, and SNK-q test., Results: On each PID, the content of Bifidobacterium and Lactobacillus in the ceca of each group with burned rats was less than that of group SI (with q values from 4.12 to 20.74, P values below 0.05); while the content of Enterococcus, Enterobacter, and Candida albicans was more than that of group SI (with q values from 2.84 to 68.29, P values below 0.05). Compared with that of group BC, the content of Bifidobacterium and Lactobacillus in the ceca of rats in group SH were increased on each PID (with q values from 2.88 to 17.57, P values below 0.05). In group SH, the content of Bifidobacterium peaked as (6.54 ± 0.35) lg (CFU/g) on PID 7, the content of Lactobacillus peaked as (7.25 ± 0.71) lg (CFU/g) on PID 21. Compared with that of group BC, the content of Enterococcus, Enterobacter, and Candida albicans in the ceca of rats in group SH was reduced on each PID (with q values from 2.79 to 29.59, P values below 0.05). Compared with that of group BC, the content of Bifidobacterium and Lactobacillus in the ceca of rats in group PPG was decreased on each PID (with q values from 2.82 to 46.56, P values below 0.05); while the content of Enterococcus, Enterobacter, and Candida albicans was significantly increased on each PID (with q values from 2.93 to 41.42, P values below 0.05). In group PPG, the content of Enterococcus peaked as (9.41 ± 0.22) lg (CFU/g) on PID 21, the content of Enterobacter peaked as (9.96 ± 0.24) lg (CFU/g) on PID 14, and that of Candida albicans peaked as (3.94 ± 0.84) lg (CFU/g) on PID 14., Conclusions: Exogenous hydrogen sulfide can subdue the growth of pathogenic bacteria while promote that of probiotics, thus helping maintain the integrity of intestinal biological barrier of rats with burn injury.

The proposed hybrid image segmentation method, based on MRI renal images, aims at extracting the cortical and medullary regions of the kidney. It incorporates the thresholding segmentation and the active contour model. To begin with, the binary mask was obtained by preprocessing and thresholding. Then, the manually set starting contour deformed like a balloon under the framework of a simplified active contour model, thus getting the initial contour of the medulla or the cortex. Finally, the initial contour deformed according to the traditional active contour model and was attracted by the actual boundary of the tissues, defined by the gradient image.

We reviewed the fermentation for dihydroxyacetone production. Microbial fermentation is better for dihydroxyacetone production as compared to chemical methods. Gluconobacter oxydans was recognized as the most important strain for industrial production of dihydroxyacetone. The dihydroxyacetone yield is associated with many factors such as substrate, product, oxygen and biomass concentration. Repeated fed-batch fermentation and immobilization fermentation were recognized as the most potential process in various fermentation mode. Construction of recombinant microorganism and optimization of process are future directions of dihydroxyacetone production.

Objective: To study whether the antiviral specificity of chicken Mx protein is determined by an amino acid substitution at position 631., Methods: We used PCR site-directed mutagenesis technique by which a single amino acid was reciprocally substituted G with A at position 2032bp of chicken Mx cDNA. Sequence analysis confirmed successful mutation from G to A at 2032bp of chicken Mx cDNA. The fragments amplified by PCR containing the mutation site were subcloned into a enteukaryotic expression vector. Then the recombinant vector was transfected into COS-I cell, Mx gene and Mx protein in the transfected COS-I cell were detected by RT-PCR and indirect fluorescence assay., Results: The results showed that COS- I cell transfected the recombinant plasmid could stably express the Mx protein. The antivirus assay showed that Mx protein had characteristics of resistance to infection of Newcastle Disease Virus., Conclusion: This study may provide a basis of the virus-resistant mechanism of Mx protein and production of virus-resistant transgenic chicken.

Objective: To study the effect of transcranial magnetic stimulation (TMS) on the rehabilitation of motor function in patients with cerebral infarction., Methods: Two hundred twenty and three patients with the initial attack of cerebral infarction were divided into three groups. (1) One hundred twenty and three patients were randomly further divided into rehabilitation subgroup (n = 63, aged 64.0 +/- 7.9, treated with TMS beginning from the 6 approximately 10 th day after onset) and control subgroup (n = 60, aged 63.5 +/- 7.9). (2) Sixty patients were divided into three subgroups according to the age: 35 approximately 55 (n = 11), 56 approximately 75 (n = 20), and over 76 (n = 30). (3) Forty patients aged 56 approximately 75 were further divided into two subgroups according to the timing of beginning of TMS: subgroup with TMS beginning within 3 months after the initial attack (n = 20) and subgroup with TMS beginning 3 months after the initial attack (n = 20). Except for TMS, the basic treatment was the same for all of the patients. TMS was given once a day for 14 days. Fugl-Meyer score, Barthel index, and central spinal cord motor conduction time (CMCT) were measured twice: just before treatment and after the 14th treatment. A difference less than 20 ms between CMCT values measured before and after TMS and failure to induce CMCT both before and after TMS were regarded as ineffective hess, and a difference more than 20 ms between CMCT values measured before and after TMS and a change from failure to induce CMCT were regarded as effective hess., Results: The effective rate was 90.5% in the rehabilitation subgroup and 68.3% in the control group (P < 0.05). The Fugl-Meyer scores were 36.3 +/- 15.8 and 33.7 +/- 13.7 in the rehabilitation subgroup and control subgroup before treatment respectively (P > 0.05), and were 51.7 +/- 15.7 and 40.0 +/- 13.9 after treatment respectively (P < 0.01). The Barthel index were 39.6 +/- 15.8 and 40.0 +/- 14.9 in the two subgroups before treatment respectively (P > 0.05) and were 50.5 +/- 15.7 and 43.9 +/- 15.3 after treatment respectively (P < 0.05). The Fugl-Meyer scores before and after TMS were 35.8 +/- 11.3 and 61.6 +/- 18.6 in the subgroup aged 35 approximately 55 (P < 0.01), 33.5 +/- 14.0 and 49.2 +/- 16.0 in the subgroup aged 56 approximately 75 (P < 0.001), and 32.1 +/- 10.7 and 37.6 +/- 11.3 in the subgroup aged over 75 (P > 0.05). The Fugl-Meyer scores were 41.2 +/- 15.7 and 59.0 +/- 22.8 before and after TCM respectively in the subgroup with early TMS treatment (P < 0.01), and were 34.3 +/- 13.5 and 45.4 +/- 14.8 respectively in the subgroup with TMS beginning 3 months after the onset (P < 0.05)., Conclusion: TMS is effective on the rehabilitation of motor function in patients with cerebral infarction. The effectiveness of TMS treatment depends on the age of the patients and timing of beginning treatment.