Understanding of supramolecular solution polymerization and interfacial polymerization via forming multiple hydrogen bonds: a computer simulation study.

By employing dissipative particle dynamics (DPD) simulations combined with stochastic polymerization models, we have conducted a detailed simulation study of supramolecular solution polymerization as well as interfacial polymerization employing a coarse-grained model which is closer to the real monomer structure. By adding bending angle potentials to coarse-grained models representing supramolecular reactive monomers, we achieved monomer model simulations for different kinds of multiple hydrogen bonds. Our simulation results indicated that for the interfacial polymerization system, the volume of the monomer caused a strong steric hindrance effect, which in turn led to a low average degree of polymerization of the product. Therefore, by appropriately reducing the volume of the reaction monomer (corresponding to different confinement ascribed to the multiple hydrogen bonds), the average polymerization degree, the degree of reaction and the polymerization rate of the monomer can be effectively improved. For the solution polymerization system and the interfacial polymerization system, a certain proportion of rigid monomers and flexible monomers (60% rigid monomers and 40% flexible monomers) are mixed. High molecular weight products can thus be obtained via the polymerization reaction. The simulation strategy proposed in this study can not only provide theoretical guidance for better design of new supramolecular systems, but also provide ideas for the further synthesis of higher molecular weight supramolecular polymers.

[Clinical observation on syndrome-differentiation acupuncture combined with rehabilitation training for autism spectrum disorder].

OBJECTIVE: To compare the clinical efficacy and safety between syndrome-differentiation acupuncture combined with rehabilitation training and simple rehabilitation training for children with autism spectrum disorder (ASD). METHODS: A total of 60 children with ASD were randomly divided into an observation group and a control group, 30 cases in each group. In the control group, routine rehabilitation training was applied; in the observation group, syndrome-differentiation acupuncture (the main points were Baihui [GV 20], Dingshenzhen, Niesanzhen, etc., the supplementary acupoints were selected according to syndrome-differentiation) combined with rehabilitation training were applied, all the treatments were given once a day, 5-day continuous treatment with 2-day interval, 12 weeks were required. Before treatment and after 6, 12 weeks of treatment, the autism treatment evaluation checklist (ATEC), childhood autism rating scale (CARS) and autism behavior checklist (ABC) scores were observed, the therapeutic effect and safety were evaluated in the two groups. RESULTS: After 6 and 12 weeks of treatment, except for the sensory perception score after 6 weeks of treatment in the control group, the item scores and total scores of ATEC, CARS scores and ABC scores were decreased compared with those before treatment in the two groups (P<0.05). After 6 weeks of treatment, the social score and total score of ATEC, CARS score in the observation group were lower than those in the control group (P<0.05); after 12 weeks of treatment, the item scores and total score of ATEC, CARS score and ABC score in the observation group were lower than those in the control group (P<0.05). The total effective rate in the observation group was 80.0% (24/30), which was higher than 56.7% (17/30) in the control group (P<0.05). There was no serious adverse reactions in the two groups, and there was no significant difference in the incidence rate of adverse reactions between the two groups (P>0.05). CONCLUSION: Syndrome-differentiation acupuncture combined with rehabilitation training could improve the core symptoms in children with ASD, especially sensory perception and social ability, and with good safety, which is superior to simple rehabilitation training.