Background Depression is a major problem among nurses; hence, it is important to develop a primary prevention strategy to manage depression among nurses. This randomized controlled trial (RCT) study aims to investigate the effects of a newly developed internet-based cognitive behavioral therapy (iCBT) program on depressive symptoms, measured at baseline and three- and six-month follow-ups, among nurses in Japan. Methods Nurses working at three university hospitals, one public hospital, and twelve private hospitals who meet inclusion criteria will be recruited and randomized either to the intervention group or the control group (planned N = 525 for each group). The newly developed iCBT program for nurses consists of six modules, which cover different components of cognitive behavioral therapy (CBT); transactional stress model (in module 1), self-monitoring skills (in module 2), behavioral activation skills (in module 3), cognitive restructuring skills (in modules 4 and 5), relaxation skills (in module 5), and problem-solving skills (in module 6). Participants in the intervention group will be asked to read these modules within 9 weeks. The primary outcome will be depressive symptoms as assessed by the Beck Depression Inventory-II (BDI-II) at baseline, three-, and six-month follow-ups. Discussion The greatest strength of this study is that it is the first RCT to test the effectiveness of the iCBT program in improving depressive symptoms among nurses. A major limitation is that all measurements, including major depressive episodes, are self-reported and may be affected by situational factors at work and participants’ perceptions. Trial registration This trial was registered at the University Hospital Medical Information Network clinical trials registry (UMIN-CTR; ID = UMIN000033521 ) (Date of registration: August 1, 2018).

ABSTRACT:The nylon4 portion in the blend films composed of nylon4 and nylon6 was degraded and completely disappeared within 4 months in two kinds of composted soils gathered from different university farms as well as pure nylon4 film reported previously, while the nylon6 portion remained even after the burial test for 15 months. Nylon4 powder was also degraded to carbon dioxide in the degradation test in an activated sludge obtained from a sewage disposal institution in Kogakuin University. Three species of microoganisms (i.e., ascomytous fungi) were isolated through the inoculation from the nylon4 film partially degraded in the soil on a medium containing nylon4 powder as a carbon source.

Different novel copolymers, ABA-type block copolymers composed of polyamide4 as outer segments and polyoxyethylene as an inner segment and AB-and ABAtype block copolyamides containing polyamide4 and another hydrophilic polyamide derived from a bicyclic lactam, were synthesized by the anionic ring-opening polymerization of 2-pyrrolidone using the corresponding acyllactamtype macromolecular activators. The degradation rate of both block copolymers containing polyamide4 segments in a composted soil was found to decrease with increasing content of the second segments, although they were also hydrophilic and/or biodegradable.