Search

This study investigated the efficacy of a novel surgical method that relies on the transient fixation of L4 in Lenke Type 5C and 6C adolescent idiopathic scoliosis. Thirty-six transient surgically treated L4 fixation patients were retrospectively evaluated. The first surgery involved mechanical correction of scoliosis; the lowest instrumented vertebra (LIV) was L4. After an average of 1.3 years (range, 0.3–3.4), the second surgery to remove transient L4 pedicle screws was performed. Radiographic parameters and SRS-22 scores were measured. Cobb’s angle, coronal balance, LIV tilting angle, and LIV coronal disc angle clearly improved after the first surgery (p

Membrane Bioreactor (MBR) process is increasingly being used as a more advanced technology for biological wastewater treatment. However, due to membrane fouling, MBR system is often restricted in field application. Membrane fouling in MBR system may cause high maintenance cost, and reduction in membrane’s lifespan. Membrane fouling reduction in MBR system was investigated using ozone in the study. Ozone is being employed in wastewater treatment, and it may change microbial characteristics in MBR system by changing the water environment to more oxidative one. Experimental results of this work were analyzed with respect to various parameters, such as BOD5, CODCr, Total Nitrogen (TN), Total Phosphorus (TP), Extracellular Polymeric Substances (EPS) production, tensile strength, Sludge Volume Index (SVI), Oxidation Reduction Potential (ORP), field emission scanning electron microscope (FE-SEM) photos, and permeability or effluent flow rate of membrane. MBR system applied with ozone injection in aeration tank showed high performance in removing water quality parameters such as BOD5, CODCr, TN, and TP. Especially removal of TP was remarkably enhanced from about 45% to 87% by ozone dosage. Before ozone dose, backwash was needed once in every two weeks. However after the ozone injection, backwash was not required for more than 4 months. When the MBR system was in operation for two weeks, membrane was in need of a backwash. However, permeability of the used membrane has gradually recovered to the level of backwashed state, and maintained the same permeability rate thereafter.

The grain boundary segregation of boron atoms in high strength low alloy steels containing 50 ppm boron was accomplished using atom probe tomography (APT) and nano-beam secondary ion mass spectroscopy (SIMS). The formation of boro-carbides under an excessive addition of boron to the steels was identified through the SIMS and TEM. The APT was performed in order to evaluate the composition of the alloying elements, such as, boron and carbon, segregated at prior austenite grain boundaries. The boron contents at the prior austenite grain boundaries were approximately 1.7 ± 0.2 at.%, which was approximately 70 times more than the amount of boron added to the steels.

The influence of stress state on the high temperature workability of rolled AZ31 Mg alloy was investigated on the basis of a processing map. To construct the processing map, high temperature compression tests were carried out on samples oriented parallel to the rolling direction at various temperatures (25 °C∼450 °C) and strain rates (10−3 s−1∼5s−1), and then the results were compared with those of a torsion test. The overall efficiency profiles of both the compression and torsion processing maps were similar to each other, but the index of dissipation efficiency in the torsion was somewhat lower than that in the compression. The microstructure of the compressed specimens revealed much finer grained structure than that of the torsion specimens. Such microstructural differences were attributed to the different tendencies of twin formation and texture evolution depending on the stress state.

Complexation of trivalent europium by a well characterized soil fulvic acid was investigated by equilibrium dialysis titration method ([FA]=24 mg·dm−3, [Eu] t =9.0·10−7−3.5·10−6 mol·dm−3, pH 6.0). The concentrations of the fulvate bound and free europium were measured radiometrically using152Eu as a tracer. The experimental results were evaluated using a bimodal normal distribution model and a plot with two overlapping normal distributions was obtained which gave two means logK (µI=7.0, σI=1.1; µII=4.9, σII=0.5) values for binding of europium by two classes of sites in fulvic acid. A multiligand model was assumed for fulvic acid, based upon the Eu(III) luminescence studies (7F0→5D0 excitation) on many organic acids as model ligands.

We recently experienced an omental teratoma in a 34-year-old woman. Ultrasonography (US) revealed a large mass of mixed echogenicity, occupying the entire lower abdomen. Computed tomography showed an inhomogeneous solid and cystic mass in the abdominal cavity containing fat and calcification.