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Objective To explore the effect of irisin on ovarian insulin resistance in rats with polycystic ovary syndrome (PCOS) and its possible mechanism. Methods Female Sprague Dawley rats of 4 weeks old were randomly divided into the control group, model group, and irisin group, with 15 rats in each group. Rats in the model group and irisin group were injected subcutaneously with DHEA 0. 06 mg/g + 0. 2 m L oil on the back of the neck, and the control group with equal volume of oil subcutaneously on the back of the neck every day, and the injection was continued for 20 days. Starting from day 21, the rats in the irisin group were intraperitoneally injected with recombinant human irisin 100 ng/g daily, and the control group and model group were intraperitoneally injected with the same amount of normal saline daily for 14 consecutive days. The next day after successful modeling, the orbital venous blood was collected, and was centrifuged to collect serum, and the serum insulin was detected by ELISA; at 6 h after the last intervention, blood was collected from abdominal aorta, and then was centrifuged to collect the serum. Serum insulin was detected by ELISA. We extracted both ovaries under aseptic conditions, took the right ovarian and used Western blotting to detect insulin receptor substrate 2 (IRS-2), glucose transporter 4 (Glut4), and phosphatidylinositol 3-kinase (PI3K) p85α subunit protein expression; the left ovarian was taken, and the expression levels of IRS-2, Glut4, PI3K p85α mRNA were detected by RT-qPCR. Results After successful modeling, serum insulin levels in the model group and irisin group were significantly higher than that in the control group (all P ＜ 0. 05); after the last intervention, the serum insulin level of the model group was higher than that of the control group (P ＜ 0. 05), and the serum insulin level of the irisin group was lower than that of the model group (P ＜0. 05); while there was no significant difference in serum insulin level between the irisin group and the control group (P ＞0. 05). Compared with the control group, the relative expression levels of IRS-2, Glut4, PI3K p85α protein and mRNA in the ovarian tissues of the model group and the irisin group decreased (all P ＜ 0. 05); however, the relative expression levels of IRS-2, Glut4, PI3K p85α protein and mRNA were higher than those of the model group (all P ＜ 0. 05). Conclusion Irisin can improve ovarian insulin resistance in PCOS rats probably by increasing ovarian insulin resistance-related signals IRS-2, Glut4, and PI3K p85α. [ABSTRACT FROM AUTHOR]

Objective：To investigate the effect of Irisin on the endometrial function in obese rats. Methods：Female SD rats were treated with high-fat diets to induce obesity, while the normal-control group (n=16) was treated with normal diets. The obese rats were randomly divided into the model-control group (n=16) and the irisin group (n=16). The rats in the irisin group were injected intraperitoneally with recombinant irisin [100 ng/（g· d）×14 days], while the rats in the two control groups were injected with normal saline. Then, female rats in estrus were mated with male rats. Eight rats were sacrificed in each group on the day 5 and day 10 of pregnancy. The pregnancy rate, average number of blastocyst and embryo morphology were observed. The expressions of leukemia inhibitory factor (LIF) and integrin αvβ3 in the implantation sites were determined. Results：The body weight in the irisin group after treatment was significantly lower than that in the model-control group (P=0.035), and the average number of blastocyst in the model-control group were significantly lower than that in the irisin group and the normal-control group (both P＜0.05). The endometrium of the normal-control group was full, and the embryo was well developed. The uterine cavity in the model-control group was large, and the embryonic development was poor. The endometrium of the irisin group was closed, and the embryonic development was well improved. The expression levels of LIF and integrin αvβ3 mRNAs and proteins in the model-control group were significantly lower than those in the normal-control group and the irisin group (all P＜0.05). Conclusions：Irisin can improve the endometrial receptivity of obese rats by increasing the expressions of LIF and integrin αvβ3 in endometrium. [ABSTRACT FROM AUTHOR]

Objective: Irisin is a factor related to insulin sensitivity. In this study, the level of serum Irisin was measured in patients with polycystic ovary syndrome (PCOS), and its significance was discussed. Methods: Eighty patients with PCOS (the PCOS group) and 60 healthy women (the control group) with regular menstrual cycle were included in our center from July 2014 to February 2016. PCOS patients were then divided into two subgroups: obese and non-obese groups, according to the body mass index (BMI). After physical examination, serum lipids, sex hormones and irisin level were measured, and compared between groups. Results: ① The levels of irisin, testosterone (T), luteinizing hormone (LH), total cholesterol (TC), BMI and waist-to-hip ratio (WHR) in the PCOS group were significantly higher than those in the control group, while the levels of high density lipoprotein cholesterol (HDL-c) and Estradiol (E2) were significantly lower (all P＜0.05). In patients with PCOS after excluding other indexes, there was a significant positive correlation between serum irisin level and T or BMI （r=0.476, P＜0.001; r=0.329, P=0.041, respectively）. ②The level of TG in the obese PCOS subgroup was higher than that in the non-obese PCOS subgroup （P=0.028）. However, the level of irisin in the obese PCOS subgroup was slightly higher than that in the non-obese PCOS subgroup, without significant difference （P=0.087）. Conclusions: The level of serum irisin in PCOS patients was significantly increased, and positively correlated with androgen and BMI, suggesting that irisin may be a factor related to PCOS. [ABSTRACT FROM AUTHOR]

The isotropy is one of the important performance indexes of the six-axis acceleration sensing mechanism, which determines the measurement accuracy of the sensor. In order to obtain the complete isotropy of the sensing mechanism, a new configuration synthesis method is proposed. Firstly, based on the Newton-Euler method and the inherent scale constraint relationship between the branches, the forward decoupling equation of the Stewart-type six-axis acceleration sensing mechanism is constructed. Secondly, the relationship between the isotropy of the sensing mechanism and the condition number of the input matrix in the forward decoupling equation is analyzed, and the mapping relationship between the branch pose and the input matrix is analyzed. Then, the configuration synthesis steps of the fully isotropic sensing mechanism are created. Finally, following this step, a "12-6" Stewart-type six-axis acceleration sensing mechanism is synthesized and a virtual experiment is carried out. The two cases of adding 0.100% random disturbance and zero disturbance are compared, and the results show that the maximum reference error of six-dimensional acceleration is 0.169%, that is, the magnification of the input and output errors is only 1.69. This shows that the new configuration has excellent isotropic properties. [ABSTRACT FROM AUTHOR]

Topological reconfiguration can improve the static stiffness and fault tolerance of parallel robots, but the problem of whether the robot can reach any specified pose without singular configuration has not been solved. Therefore, this paper takes the reconfigurable 3-RRR planar parallel robot as the research object, and proposes a path planning method that can realize “ point-to-point ” tracking. Firstly, the inverse kinematics model before reconfiguration is established, and six paths based on topological reconfiguration are found. Then, a “ four-step ” planning algorithm is constructed, which is suitable for “ point-to-point ” path tracking of reconfigurable parallel robots with any degree of freedom. It has intuitive geometric interpretation and can eliminate all singularities. The effectiveness of the planning algorithm is verified by an example. Further, based on the screw theory, the input and output transfer indexes under each input mode are calculated, and the optimal solution of the input mode is obtained by using the local transfer index. Finally, the “ point-topoint ” path planning algorithm is extended to continuous path planning. [ABSTRACT FROM AUTHOR]

A new type of variable cell kinematic pair is designed, which can be used to realize the reconstruction of 3-revolute‑joint, revolute‑joint, revolute‑joint (RRR) planar parallel mechanism. The kinematic models of R-R-R and revolute‑joint, prismatic‑joint, revolute‑joint (R-P-R) modes are derived and verified, including forward and inverse solutions, which can be used to calculate the singular configuration and workspace of parallel mechanism.The research results show that the designed variable cell kinematic pair can realize the reconfiguration function of the mechanism. The forward kinematics algorithms in the two modes are consistent, both of which are unary eighth-order equations. The inverse kinematics solution of R-RR type is three quadratic equations, and the inverse kinematics solution of R-P-R type can be expressed directly by the distance formula between two points. Finally, the correctness of the kinematic model is verified by the virtual prototype experiment. [ABSTRACT FROM AUTHOR]

Based on the traditional three degree of freedom (DOF) planar parallel mechanism, a novel reconfigurable 3-DOF planar parallel mechanism is proposed. Firstly, based on the theory and method of topology design of the parallel mechanism position and orientation characteristic (POC). The switch between the 3-revolute-joint, prismatic-joint, revolute-joint (3-RPR) and 3-revolute-joint, revolute-joint, revolute-joint (3-RRR) planar parallel mechanisms is realized through a reconfigurable branch chain. Then, taking 3-RRR configuration as an example, the important topological indexes of the mechanism, such as POC, DOF and coupling degree, are analyzed. Based on the structural characteristics and geometric constraints of the mechanism, the inverse kinematics model is derived by using the closed vector method. Finally, the position workspace of the mechanism is analyzed based on the geometric constraint method of the branched chain and the inverse solution model respectively. This work provides not only a new idea for the analysis of mechanism workspace, but also a new choice for the design of mechanism. [ABSTRACT FROM AUTHOR]

[Objective] In this paper, the Dosage-Response Relationship of Simulated Acid Rain (SAR) on plants was investigated and fitting analysis method was used to analyze the toxicity threshold of SAR stress on plants. The study could provide a theoretical basis for screening plants suitable in acid rain area. [ Method ] This study investigated the sensitivity of plant species to SAR based on the modeled Dosage-Re sponse Relationship on the total chlorophyll content (Chi) of 26 types of plant species, subjected to 50 days exposure to SAR. Model fitting allowed quantitative evaluation of the Dosage-Response Relationship and an accurate estimation of the EClO, termed as the pH of the SAR re sulting in a Chi 10% lower than the reference value to obtain the toxicity threshold of the Chi of these 26 plants under SAR stress. [Result] The response of Chi in leaves of different plants to SAR was significantly different. These Dosage-Response Relationships were promotion type, non-affection type, low promotion-high inhibition type and inhibition type. Based on the fitting calculation of the Dosage-Response Relationship, the toxicity threshold of the Chi of 26 plants affected by SAR stress was obtained. [ Conclusion] ( i ) The Chi of plant leaves could effectively characterize the Dosage-Response Relationship of SAR on plants. ( ii ) The effect of SAR on the Chi of plant leaves had a dual effect of promotion and inhibition, which meaned that the toxic effect of acid rain coexists with the effect of fenilization. ( iii) Threshold value of Viburnum odoratissimum Ker-Gaw!., Musa basjoo Sieb. & Zucc. and Gnetum montanum Markgr. was pH< 2. 0. The cultivation of these plants could effectively protect the urban environment and maintain the ecological balance in acid rain area of Southwest China. [ABSTRACT FROM AUTHOR]

With the development of parallel robot technology，the necessity of studying the workspace and singularity of parallel robot is presented to improve the motion performance. The research status and characteristics of workspace and singularity at home and abroad are described in detail based on different research methods. Furthermore，individual innovative ideas and common problems for different research methods of workspace and singularity are pointed out. Through deeply analyzing the principle of research methods，the breakthrough is found to solve common problems. Meanwhile，the remaining problems in research are analyzed. Combining with the future development trend，breakthroughs in structural synthesis and theoretical innovation can provide strong impetus for the development of parallel robot. The conclusions and prospects provide valuable references for researchers engaged in this field. [ABSTRACT FROM AUTHOR]

Using Ganoderma as raw material, one kind of Ganogerma lucidem polysaccharide ( abbreviated GLP) was extracted and the carboxymethyl product( CM-GLP) was prepared. Using the carboxymethylated degree of substitution ( DS) as an indicator, the carboxymethyl modification conditions of GLP were optimized by using the orthogonal test. Using blank tobacco shred as control and the moisture content of tobacco shred as an indicator , the physical moisture retention properties of CM-GLP , GLP , propylene glycol(PG) and glycerol were measured , and the effects of these two samples and two traditional humectants on the sensory comfort levels in cigarettes were investigated. The results showed that： 1 ) the optimum technological condition was 85 g of chloroacetic acid, 4. 5 mol/L, of NaOH solution concentration, 60 °C of reaction temperature , and 2 h of reaction time, and the mean value of DS under this condition was 1.36; 2 ) under low humidity conditions the moisture retention property of CM-GLP was superior to PG and glycerol, and the moisture retention property of GLP was slightly worse than PG, under high humidity conditions, four differｅｎｃｅ ｗａｓ ｎｏｔ ｏｂｖｉｏｕｓ； ３） ＣＭ-ＧＬＰ ｐｏｓｓｅｓｓｅｓ ｔｈｅ ｒｏｌｅｓ ｏｆ ｍａｋｉｎｇ ｃｉｇａｒｅｔｔｅ ｓｍｏｋｅ ｍｅｌｌｏｗ ａｎｄ ｆｕｌｌ, ｒｅｄｕｃｉｎｇ ｉｒｒｉｔａｔｉｏｎ ａｎｄ ｅｌｅｖａｔｉｎｇ ｃｏｍｆｏｒｔａｂｌｅ ｍｏｕｔｈｆｅｅｌ． [ABSTRACT FROM AUTHOR]