Fast convergence to equilibrium for long-chain polymer melts using a MD/continuum hybrid method

Effective and fast convergence toward an equilibrium state for long-chain polymer melts is realized by a hybrid method coupling molecular dynamics and the elastic continuum. The required simulation time to achieve the equilibrium state is reduced drastically compared with conventional equilibration methods. The polymers move on a wide range of the energy landscape due to large-scale fluctuation generated by the elastic continuum. A variety of chain structures is generated in the polymer melt which results in the fast convergence to the equilibrium state.Comment: 13 page

Searching for harmless substitute solvents for dichloromethane to adhere PMMA solventing

Dichloromethane (CH_2Cl_2) is good solvent to adhere PMMA, so it is used widely in industrial fields. It has a bad effect, however, on organisms and pollutes environment. Its solution and vapor have a toxic effection blood and nerve centers. It it is also said to cause mutation of the gene. When it is burned, dichloromethane generates phosgene (CCl_2O) which is known as a poison and air polluting substance. It is a serious problem that dichloromethane is harmful to our health. The purpose of this study is to search for reagents that have as high performance for adhesives as dichloromethane, and that don\u27t have a bad effect on organisms and the environment. The specimens were PMMA plates (1mm × 1cm × 5cm) made by injection molding, with an average molecular weight between 100,000 and 150,000. First, we selected several solvents were PMMA. Then, solvents were analyzed with FT-IR and TG/DTA for chemical changes, and the peeling test for measuring the adhesion strength, compared with dichloromethane. It was proposed that Acetone, Ethylene glycol monomethyl ether and 2-Ethoxy ethanol are possible and the results substitutes dichloromethane for adhering PMMA

The effects of comorbid Tourette symptoms on distress caused by compulsive-like behavior in very young children: A cross-sectional study

Background Many children 4 to 6 years old exhibit compulsive-like behavior, often with comorbid Tourette symptoms, making this age group critical for investigating the effects of having comorbid Tourette symptoms with compulsive-like behavior. However, these effects have not yet been elucidated: it is unclear whether having comorbid tics with compulsive-like behavior leads to lower quality of life. This cross-sectional study aims to investigate the effect of comorbid Tourette symptoms on distress caused by compulsive-like behavior in very young children. Methods Self-administered questionnaires were distributed to guardians of children aged 4 to 6 attending any of the 59 public preschools in a certain ward in Tokyo, Japan. The questionnaire contained questions on the presence of Tourette symptoms, the presence of specific motor and vocal tics, frequency/intensity of compulsive-like behavior, and the distress caused by compulsive-like behavior, which was rated on a scale of 1 to 5. Additionally, questions on autism spectrum disorder (ASD) traits, attention-deficit/hyperactivity disorder (ADHD) traits, internalizing behavior traits, and externalizing behavior traits were included in the questionnaire as possible confounders of distress caused by compulsive-like behavior. Wilcoxon rank-sum tests were conducted to compare the distress caused by compulsive-like behavior and frequency/intensity of compulsive-like behavior between children in the Tourette symptoms group and the non-Tourette symptoms group. Furthermore, a stepwise regression analysis was performed to assess the effects of the independent variables on distress caused by compulsive-like behavior. Another stepwise regression analysis was performed to assess the relationship between distress caused by compulsive-like behavior and the presence of five specific motor and vocal tics. Results Of the 675 eligible participants, distress due to compulsive-like behavior was significantly higher in children in the Tourette symptoms group compared to the non-Tourette symptoms group (2.00 vs 1.00, P < 0.001). Stepwise regression analysis showed that frequency/intensity of compulsive-like behavior, being in the Tourette symptoms group, ASD traits, and internalizing behavior traits were predictors of distress due to compulsive-like behavior. Two specific tics, repetitive noises and sounds and repetitive neck, shoulder, or trunk movements, were significant predictors of distress due to compulsive-like behavior. Conclusions Comorbid Tourette symptoms may worsen distress caused by compulsive-like behavior in children 4 to 6 years old, and specific motor and vocal tics may lead to greater distress

The possible effects of the Japan Society of Clinical Oncology Clinical Practice Guidelines 2017 on the practice of fertility preservation in female cancer patients in Japan

Abstract Purpose In 2017, the first guidelines for fertility preservation in cancer patients were published in Japan. However, the impact of the guidelines remains unknown. Therefore, the authors conducted a nationwide survey on cryopreservation procedures in the period from shortly before to after publication of the guidelines (2016–2019) and compared the results with our previous survey (2011–2015). The authors also surveyed reproductive specialists’ awareness of the guidelines and implementation problems. Methods The authors sent a questionnaire to 618 assisted reproductive technology facilities certified by the Japanese Society of Obstetrics and Gynecology. Results The authors received responses from 395 institutions (63.8%). Among them, 144 institutions conducted cryopreservation for cancer patients (vs. 126 in 2011–2015) and performed 2537 embryo or oocyte and 178 ovarian tissue cryopreservation procedures (vs. 1085 and 122, respectively). Compared with the previous period, indications were more varied and protocols for controlled ovarian stimulation were more standardized. Reproductive specialists’ interest in oncofertility was high, but many reported three main difficulties: selecting a treatment method, storing samples in the long term, and securing the necessary human resources. Conclusions The practice of fertility preservation in cancer patients in Japan has been considerably affected by the first Japanese guidelines