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Purpose As computed tomography (CT) imaging is the most commonly used modality for treatment planning in radiation therapy, metal artifacts in the planning CT images may complicate the target delineation and reduce the dose calculation accuracy. Although current CT scanners do provide certain correction steps, it is a common understanding that there is not a universal solution yet to the metal artifact reduction (MAR) in general. Particularly noting the importance of MAR for radiation treatment planning, we propose a novel MAR method in this work that recruits an additional tilted CT scan and synthesizes nearly metal‐artifact‐free CT images. Methods The proposed method is based on the facts that the most pronounced metal artifacts in CT images show up along the x‐ray beam direction traversing multiple metallic objects and that a tilted CT scan can provide complementary information free of such metal artifacts in the earlier scan. Although the tilted CT scan would contain its own metal artifacts in the images, the artifacts may manifest in a different fashion leaving a chance to concatenate the two CT images with the metal artifacts much suppressed. We developed an image processing technique that uses the structural similarity (SSIM) for suppressing the metal artifacts. On top of the additional scan, we proposed to use an existing MAR method for each scan if necessary to further suppress the metal artifacts. Results The proposed method was validated by a simulation study using the pelvic region of an XCAT numerical phantom and also by an experimental study using the head part of the Rando phantom. The proposed method was found to effectively reduce the metal artifacts. Quantitative analyses revealed that the proposed method reduced the mean absolute percentages of the error by up to 86% and 89% in the simulation and experimental studies, respectively. Conclusions It was confirmed that the proposed method, using complementary information acquired from an additional tilted CT scan, can provide nearly metal‐artifact‐free images for the treatment planning.

Adolescents’ exposure to internet pornography and its negative effects on healthy sexual development have been extensively investigated. However, little research has addressed the identification of...

Clinical results of high tibial osteotomy (HTO) deteriorate over time despite the initial satisfactory results. Several knees may require a conversion to total knee arthroplasty (TKA) because of failure such as the progression of degenerative osteoarthritis and the loss of the correction angle. It is important to know the long-term survival rate and common reason of failure in HTO to inform patients of postoperative expectations before surgery and to prevent surgical errors during surgery. In addition, it has been reported that clinical and radiological results, revision rate, and complication rate were poorer than those in patients without a previous HTO. There are few review articles that describe why conversion TKA after HTO is surgically difficult and the results are poor. Surgeons have to avoid the various complications and surgical errors in this specific situation. We would like to present the considering factors and technical difficulties during conversion TKA after HTO with a review of the literature. We could conclude through the review that the correction of deformity, lower amount of tibial bone resection, and sufficient polyethylene insert thickness, restoration of the joint line height, and adequate ligament balancing can be helpful in overcoming the technical challenges encountered during TKA following HTO.

La 0.8 Sr 0.2 Ga 0.8 Mg 0.2-x Zn x O 2.8 (LSGMZ, X = 0-0.05) was prepared using a solid state reaction method. Two secondary phases (LaSrGaO₄ and LaSrGa₃O 7 ) of powders were identified by X-ray diffraction analysis. The relative amount of these secondary phases depended on the calcination conditions (temperature and time) and Zn content. The sintering density of LSGMZ was enhanced by increasing the Zn content and calcination temperature at the low sintering temperatures (1250-1300℃). The relationship between the sintering density of LSGMZ and the synthesis conditions was discussed considering the phase analysis results.

This study examined the effects of TiN (titanium nitride) and WC (tungsten carbide) coatings on the fatigue characteristics of dental implants using a sinusoidal cyclic loading machine under load between 42–420 N and 58–580 N according to the ISO 14801. In this study, an abutment screw was coated with a TiN and WC film by EB-PVD and sputtering, respectively. For the fatigue test, the implant fixture and abutment were tightened to a torque 32 Ncm using a digital torque gauge with 0.1 Ncm accuracy. Field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) were used to observe the coated surface and fracture surface of the abutment screw. The uncoated abutment screws contained scratches caused by the mechanical process, whereas the TiN and WC coated screws showed a smooth surface at the screw thread and screw valley. The mean fatigue life of the uncoated, TiN coated, and WC coated abutment screw at 420 N was 5.8 × 10 5 , 8.2 × 10 5 and 10 6 cycles, respectively. At 580 N, the mean fatigue life of the uncoated, TiN coated and WC coated abutment screw was 2.1 × 10 4 , 4.1 × 10 4 and 2.3 × 10 4 cycles, respectively. The uncoated abutment screw showed the beach mark and fatigue striation. On the other hand, in the case of TiN and WC coated abutment screws, the semi-cleavage fracture and ductile fracture appeared at 420 N. Semi-cleavage fracture and massive fatigue striation with a step of 0.5 μm/cycle were observed in TiN coated abutment screw, whereas a minute slip band was noted and the interval of fatigue striation increased to several μm/cycle in the WC coated screw at 580 N.

The properties of green sheet were investigated in order to understanding an effects of organic solvent mixture ratio for solid oxide fuel cells fabrication. The purpose of this work is to optimize the slurry condition using the design of experiment to improve green sheet properties. The elongation increased with increasing amount of binder and solvent. With increasing amount of solvent, the air permeability increased but the tensile strength decreased. The best properties of the green sheet appeared amount of the binder 17 wt%, solvent 35 wt% and powder 48 wt%. The optimum condition of green and sintered density for solid oxide fuel cells fabrication was obtained in the sample pressured at 800 .

Aims: To understand the intracellular reducing power metabolism, growth and intracellular NAD(P)H concentrations of a phosphoglucose isomerase (pgi)-disrupted Escherichia coli (KS002) were investigated with the expressions of redox enzymes. Methods and Results: The isogenic pgi-mutation enabled E. coli to harbour two times both the intracellular NADPH and NADH at half the growth rate. The wild-type expressing NAD-dependent malic enzyme (maeA) was incapable of sufficient growth (

Dental implant systems are subject to failure in the screw connection part which can occur due to screw loosening or fracture. For solving the problem of loosening, some researchers had carried out the TiN(titanium nitride) and WC(tungsten carbide) coating on the abutment screw, while fatigue failure may still be not researched as an issue of coating materials. In this study, fatigue test was performed to estimate the fatigue fracture of coated abutment screw for implant system according to the ISO 14801. For this purpose, TiN and WC film coating was carried out on the abutment screw using EB-PVD and sputtering, respectively. For the fatigue test, the implant fixture and abutment were tightened to a torque 32Ncm using digital torque gauge with 0.1Ncm accuracy. Each prepared samples were fixed to uniaxial sinusoidal cyclic loading machine (ADT-AV01k1, Shimadzu, Japan) under load control between 42-420N and 58-580N. Fractured surface was observed with FE-SEM and EDS. The fatigue life of implant system used TiN and WC coated abutment screw was found to be relatively longer compared to non-coated abutment screw at 420N. Also, fatigue life of TiN coated sample showed longer than that of other samples at 580N. Afterthe fatigue test at 420N, fatigue striations were showed on the fractured surface of non-coated abutment screw. The semi-cleavage surface was mainly observed on the TiN coated surface. Fatigue striations were regularly appeared at crack propagation step with striation thickness of 0.5μm/cycle.

In this study, surface characteristics of dental implant fixture with various manufacturing process have been researched using electrochemical methods. The dental implant fixture was selected with 5 steps by cleaning, surface treatment and sterilization with same size and screw structure; the 1st step-machined surface, 2nd step-cleaned by thinner and prosol solution, 3th step-surface treated by RBM (resorbable blasting media) method, 4th step-cleaned and dried, 5th step-sterilized by gamma-ray. The electrochemical behavior of dental implant fixture has been evaluated by using potentiostat (EG&G Co, 2273A) in 0.9% NaCl solution at . The corrosion surface was observed using field-emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDS). The step 5 sample showed the cleaner and rougher surface than step 3 sample. The step 5 sample of implant fixture treated by RBM and gamma sterilization showed the low corrosion current density compared to others. Especially, the step 3 sample of implant fixture treated by RBM was presented the lowest value of corrosion resistance and the highest value of corrosion current density. The step 3 sample showed the low value of polarization resistance compared to other samples. In conclusion, the implant fixture treated with RBM and gamma sterilization has the higher corrosion resistance, and corrosion resistance depends on the step of manufacturing process.

Titanium and titanium alloys are widely used for orthopedic and dental implants for their superior mechanical properties, low modulus, excellent corrosion resistance and good biocompatibility. In this study, corrosion behaviors of nanotube formed on the bone plate of Ti-6Al-4V alloy for dental use have been investigated. nanotubes were formed on the dental bone plates by anodization in containing 0.6 wt % NaF solution at . Electrochemical experiments were performed using a conventional three-electrode configuration with a platinum counter electrode and a saturated calomel reference electrode. Anodization was carried out using a scanning potentiostat (EG&G Co, Model 263A USA), and all experiments were conducted at room temperature. The surface morphology was observed using field emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy(EDS). The corrosion behavior of the dental bone plates was examined using potentiodynamic test(potential range of -1500~2000 mV) in a 0.9% NaCl solution by potentiostat (EG&G Co, PARSTAT 2273. USA). The inner diameter of nanotube was about 150~180 nm with wall thickness of about 20 nm. The interspace of nanotube to nanotube was 50 nm. The passive region of the nanotube formed bone plates showed the broad range compared to non-nanotube formed bone plates. The corrosion surface of sample was covered with corrosion products.

Overexpression in Escherichia coli and functional characterization of the group II chaperonin from the hyperthermophilic archaeum Pyrococcus horikoshii OT3 were investigated in this study. PhCpn, the chaperonin gene from the P. horikoshii OT3, was amplified by PCR from the P. horikoshii genomic DNA, subcloned into pET21a vector, and expressed in three E. coli host cells such as BL21, Rosetta, and Codonplus (DE3). Among these host cells, E. coli Rosetta showed the highest expression level of recombinant PhCpn at induction with 1 mM IPTG. The recombinant PhCpn was purified to 91% by heat-shock treatment and anion-exchange chromatography. The ATPase activity of the purified PhCpn increased in a PhCpn concentration-dependent manner. Also, PhCpn protected the inorganic phosphatase from thermal inactivation at 85 and 110°C, speculating that PhCpn is effective in in vitro holding of the protein. The holding efficiency was enhanced by the addition of Mg2+ ion. Through the coexpression of pro-carboxypeptidase B (pro-CPB) and PhCpn in E. coli Rosetta, pro-CPB was produced as a soluble and active form with a marked yield. This result indicated that PhCpn facilitated the in vivo correct folding of pro-CPB and could be used as powerful and novel molecular machinery for the production of recombinant proteins as soluble and active forms in E. coli.

To better understand how the reducing power of either NADH or NADPH affects cell growth, Escherichia coli strains expressing either NADH-dependent or NADPH-dependent azoreductase (EC 1.6.5.2), which mediates the reduction of an azo dye, were cultured in glucose minimal medium in the presence of 200 muM methyl red. Growth rates in NADH-perturbed, NADPH-perturbed, and control cells were 0.05, 0.12, and 0.13 h(-1), respectively. In addition, glucose consumption in NADH-perturbed cells was 10.8 g glucose/g cell, while that of control and NADPH-perturbed cells was very similar (3.6 vs 3.8 g glucose/g cell) during the perturbation phase. Therefore, NADH perturbation had a larger effect than NADPH on cellular growth.

This paper proposes an obstacle avoidance algorithm for translational and rotational motions of four wheels independent steering (4WIS) automatic guided vehicles (AGV) based on fuzzy potential method (FPM) and backstepping control method. Firstly, the system is described and mathematical modeling is introduced. The AGV consists of 4 wheels driving system, laser measurement system, laser navigation system and industrial PC. Secondly, the Fuzzy Potential Field (FPM) is proposed to obtain an optimal path for an AGV. The shape and the size of the vehicle are considered when the FPM generates the optimal path from the current position to the goal position. This method allows the rectangular shape AGV to avoid unknown obstacles safely and efficiently. Backstepping controller is proposed to track the optimal path generated by FPM. Finally, the simulations are conducted to verify the effectiveness of the proposed algorithm. The simulation results show that the proposed algorithm can make the 4WIS-AGV avoid the obstacles in cluttered environment.

The Smooth Particle Hydrodynamics (SPH) method is a Lagrangian approach. The fluid is approximated by particles that are free to move around with physical properties (see Fig. 1, left).

Our preliminary experiment demonstrated that a n-hexane/EtOH (9:1, volume) extract of Glycyrrhiza uralensis (licorice) caused a significant induction of NAD(P)H:oxidoquinone reductase (NQO1), one of the well-known phase 2 detoxifying enzymes. We isolated dehydroglyasperin C (DGC) as a potent phase 2 enzyme inducer from licorice. DGC induced NQO1 both in wild-type murine hepatoma Hepa1c1c7 and ARNT-lacking BPRc1 cells, indicating that the compound is a monofunctional inducer. The compound induced not only NQO1 but also some other phase 2 detoxifying/antioxidant enzymes, such as glutathione S-transferase, gamma-glutamylcysteine synthase, glutathione reductase, and heme oxygenase 1. Similar to most monofunctional inducers, DGC caused the accumulation of Nrf2 in the nucleus in dose- and time-dependent manners and thereby activated expression of phase 2 detoxifying enzymes. It also resulted in a dose-dependent increase in the luciferase activity in the reporter assay, in which HepG2-C8 cells transfected with antioxidant response element (ARE)-luciferase construct were used, suggesting that the induction of phase 2 detoxifying and antioxidant enzymes could be achieved through the interaction of Nrf2 with the ARE sequence in the promoter region of their genes.

Materials and Methods: From February 2005 to January 2014, 20 cases (19 patients) with malignant bone tumor involving the proximal femur with pain or complicated pathologic fracture were treated with segmental resection and limb salvage operations with tumor prostheses. Mean age was 63.1 years (range 35-86). Fourteen patients were male and six ones were female. The mean follow-up period was 20 months (1-94 months). There were 15 cases of metastatic bone tumor, 4 cases of osteosarcoma, and 1 case of multiple myeloma. The primary tumors of the metastatic bone tumors included 4 lung cancers, 3 hepatocellular carcinomas, and 3 renal cell carcinomas. Other primary tumors were breast cancer, thyroid cancer, colon cancer, prostate cancer, and malignant spindle cell tumor, each in 1 case. Modular tumor prostheses were used in all cases; (Kotz’s® Modular Tumor prosthesis (Howmedica, Rutherford, New Jersey) in 3 cases, MUTARS® proximal femur system (Implantcast, Munster, Germany) in 17 cases). Perioperative pain was assessed with Visual Analogue Scales (VAS). Postoperative functional outcome was assessed with Musculoskeletal Tumor Society (MSTS) grading system.