Three kinds of extraction constants, K ex , K ex , and K ex+ , were evaluated from the improved model that the following three component-equilibria were added to a previously-proposed model for an overall extraction: M 2+
Extraction constants, defined as ex = [HPic] o /[H + ][Pic − ], for picric acid (HPic) into ten diluents were spectrophotometrically determined at 298 K, where the subscript "o" refers to an organic (o) phase which is composed of the diluent. Their values for the HPic extraction into benzene and chloroform were fairly consistent with those reported before. From the ex values, distribution constants (D,HPic) of HPic into the o phases were estimated using the thermodynamic relation ex = D,HPic HPic , where HPic corresponds to a protonation constant of Pic − in water. Thereby, contributions of functional groups, such as-Cl and-CH 3 , involved in the diluents molecules to D,HPic were discussed. The same discussion was also applied for the distribution of the ion pair, composed of CdPic 2 and 18-crown-6 ether, into the diluents.
We developed a new cranioplasty method that utilizes artificial bone made of ultra-highmolecular -weight polyethylene, with a wedge-shaped edge (UHMWPE Wing). This study shows the methods and data of case series and finite element analyses with the UHMWPE Wing. A circumferential wing was preoperatively designed for a custom-made artificial bone made of UHMWPE to achieve high fixed power and to minimize the usage of cranial implants. Here, we present 4 years of follow-up data and finite element analyses for patients treated with the UHMWPE Wing between February 2015 and February 2019. Eighteen consecutive patients underwent cranioplasty using our UHMWPE Wing design. There were no postoperative adverse events in 17 of the patients for at least 18 months. One case of hydrocephalus experienced screw loosening and graft uplift due to shunt malfunction. Placement of a ventriculo-peritoneal shunt immediately returned the artificial bone to normal position. Finite element analyses revealed that a model using the UHMWPE Wing had the highest withstand load and lowest deformation. This is the first report on the UHMWPE Wing method. This method may enable clinicians to minimize dead space and achieve high strength in cranioplasty.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.