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Notes: Indium Tin Oxide (ITO) films were deposited on non-alkali glass substrate by magnetronsputtering using commercial ITO target (target A) and improved ITO target (target B). Depositionswere carried out at total gas pressure (Ptot) of 0.5 Pa, substrate temperature (Ts) of RT ~ 300 ºC,oxygen flow ratio [O2/(O2+Ar)] of 0 ~ 1.0% and dc power of 100W. Target B showed relativelyhigher stability in film resistivity with increasing sputtering time, i.e., erosion ratio of target surface.Optimum oxygen ratio to obtain the lowest resistivity was decreased with increasing substratetemperature. The lowest resistivity was 1.06x10-4 6cm for the film deposited using target B atO2/(O2+Ar) ratio of 0.05% and at Ts =300 ºC

Notes: In this study, muscle-derived stem cell (MDSC)/Pluronics/polycaprolactone (PCL)microparticle hybrid mixture was prepared as a potential injectable urethral bulking agent for thetreatment of urinary incontinence. The MDSCs were isolated from the gastrocnemius muscles ofSD rats by a modified preplate method and characterized through FACS analysis using variousprimary antibodies (CD34, Sca-1, CD45 and desmin). The hybrid mixture was prepared by themixing of PCL microparticles (diameter, 100~200 μm) and MDSCs-containing thermo-sensitivePluronic (F127/F68 mixture) solution (4.5/5.5, w/v). The hybrid mixture was easily injectedthrough 18G needle into the body and stably remained in the applied site without initial volumedecrease, owing to a well-packed structure of PCL particles exhibited in the hybrid mixture. It wasobserved that the MDSCs were stably grown in the hybrid mixture without severe inflammation andimmune reaction. From the results, we recognized that the hybrid mixture can be a good candidateas an injectable bulking agent for the treatment of urinary incontinence, due to their goodinjectability, volume retention and biocompatibility

Notes: Chitosan cylindrical scaffolds with gradually increasing pore size along the longitudinaldirection were fabricated by a novel centrifugation method to investigate pore size effect on cellinteractions. The scaffold was fabricated by the centrifugation of a cylindrical mold containing fibril-likechitosans. The pore size ranges of the scaffold could be controlled by adjusting the centrifugal speed: thescaffold with gradually increasing pore size (from ~80 #m to ~400 #m) and porosity (from ~82 % to~93 %) along the cylindrical axis was obtained by applying the centrifugal speed, 3,000 rpm. The scaffoldsections were examined for their in vitro cell interactions using different kinds of cells (fibroblasts,chondrocytes, and osteoblasts) in terms of scaffold pore sizes. It was observed that different kinds of cellswere shown to have different pore size ranges in the scaffold for effective cell growth. The chitosanscaffold section with ~400 #m pore size showed better cell growth for chondrocytes and osteoblasts,while the scaffold section with ~190 #m pore size was better for fibroblast growth. The pore size gradientscaffolds fabricated by the centrifugation method can be a good tool for the systematic studies of theinteractions between cells or tissues and scaffolds with different pore size

Notes: Electrospinning is a fabrication process that can produce highly porous nano-scale fiber-basedmatrices using an electrostatically driven jet of polymer solution. This method represents an attractiveapproach for polymeric biomaterial processing which provides the membrane structure that may retainmechanical strengths, flexibility, and high surface area. In this study, we prepared a guided boneregeneration (GBR) membrane with selective permeability, hydrophilicity, good mechanical strength andadhesiveness with bone using polycaprolactone (PCL) and Tween 80 by the electrospinning method. Theprepared PCL and PCL/Tween 80 electrospun sheets were characterized via morphology observation,mechanical property, water absorbability, and model nutrient permeability. It was observed that thePCL/Tween 80 (3 wt%) electrospun sheet have an effective permeation of nutrients as well as the goodmechanical strength to maintain a secluded space for the bone regeneration. From the results, thehydrophilized PCL/Tween 80 (3 wt%) electrospun sheet seem to be a good candidate as a GBRmembrane

Notes: Porous polydioxanone (PDO)/polyvinyl alcohol (PVA) scaffolds were fabricated byblending PDO with a small amount of PVA to improve the hydrophilicity and cell/tissuecompatibility of the scaffolds for tissue engineering applications. PDO/PVA scaffolds with differentPVA compositions up to 10 wt% were fabricated by a melt-molding particulate-leaching method(non-solvent method). The prepared scaffolds exhibited highly porous, uniform open-cellular porestructures. The PDO/PVA scaffolds with PVA compositions more than 5 % were easily wetted incell culture medium. The hydrophilized PDO/PVA (5 wt%) scaffold showed better cell adhesionand growth than the control hydrophobic PDO scaffold. The PDO/PVA (5 wt%) scaffold alsoshowed faster tissue infiltration into the scaffold than the PDO scaffold. It seems that 5 wt%addition of PVA to PDO to fabricate PDO/PVA scaffolds is enough for improving thehydrophilicity and cell/tissue compatibility of the scaffolds

Notes: Meniscus is the most commonly injured structure in the knee joint. Resection of themeniscus as well as the torn menisci is known to induce the degeneration of the articular cartilage.Replacement of the resected meniscus by allograft is limited by its availability and potential diseasetransmission. Artificial prostheses are being tried in an attempt to regenerate the meniscal tissue andwe developed the biodegradable porous polycaprolactone(PCL) scaffold, which acts as a temporaryscaffold to enable the regeneration of a new tissue in time. We report the results of rabbitimplantation model. Biodegradable PCL scaffold coated with type I collagen with pores sized100~150 +m and with compression modulus 400 kpa were fabricated by melt-molding particulate-leaching method. The molds were made using the native meniscus of the rabbit. Medial meniscus ofright knee was partially removed through arthrotomy, leaving anterior 1/5 of the meniscus, aftersectioning medial collateral ligament. The implant was attached to the peripheral capsule andremnant anterior meniscus with sutures. The medial meniscus of the left knee was removed andserved as a control without replacement. The regenerated meniscus was harvested at 4 & 12wksafter implantation. In addition to the routine histology of the tissue regenerated and remnantscaffold, junction between the normal meniscus and the regenerated tissue, and cartilage surfacedegeneration was observed. After 4 and 12 weeks the scaffolds, although considerable amount ofthe materials remained, were largely filled and covered with fibrous tissue which was assumed to bederived from synovial tissue of peripheral capsule. The tissue grossly resembling the nativemeniscus was maintained and spindle shaped cells with extracellular matrices were observedhistologically. Neither cells with chondrocytic phenotype nor distinct cartilage matrices wereobserved until 12 weeks. The bonding between the regenerated tissue and the peripheral synovialcapsule was firm and solid in all cases. The tissue bridges between the native meniscus and theregenerated tissue were found in 9/10 operated knees. Articular surface degeneration was notdifferent between experimental and control groups except one case. More or less, the extrusion ofthe meniscus was found in almost all knees. This study revealed that meniscal replacement withPCL polymer prosthesis was feasible and led to adequate tissue formation. Long term studies onadaptive remodeling will be required

Notes: In the ASME Code Section III ‘design by analysis’ approach, stresses are determined bynumerical method and compared with corresponding stress limits. This approach provides severalstress criteria for fatigue life assessment and procedures for categorizing the representative stresscomponents. Since the stress criteria were derived from two-dimensional basis, however, it mayinappropriate to delineate structural components with complex geometry. In this paper, detailedtransient analyses are performed for modular pressurizer with an asymmetric geometry, whichincludes perforated parts to mount various piping and equipments. Also, the applicability of aneffective elastic modulus to consider the perforation and the appropriateness of stress linearizationmethod using stress classification line are assessed. Then, the cumulative usage factor as well as stressintensities at critical locations of the pressurizer are calculated and compared with correspondingallowable design stress limits. The key findings of this work can be used to make regulatory guides forevaluation and confirmation of structural intensity of components with asymmetric perforated parts

Notes: In this paper, conservatisms of current plugging criteria on steam generator tubes arereviewed and six new failure prediction models for dual through-wall cracks are proposed. In order todetermine the optimum ones among these local or global failure prediction models, a series of plasticcollapse tests and corresponding finite element analyses are carried out with respect to two adjacentaxial through-wall cracks in thin plates. Then, reaction force model, plastic zone contact model andCOD (Crack Opening Displacement) base model were selected as the optimum ones for integrityassessment of steam generator tubes with dual cracks