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A383 aluminum alloy high pressure die castings were solution treated at 490 °C for six durations ranging between 15 and 180 min, subsequently quenched in water and naturally aged for 4 days. The effect of solution treatment time on the evolution of microstructure and tensile properties were determined previously (G. Eisaabadi et al. Mater. Sci. Eng. A, 722, pp. 1–7, 2018.) In the current study, the tensile deformation characteristics of A383 alloy castings were determined by analyzing work hardening rate versus true stress in Kocks-Mecking plots. Results showed that (i) there was a sudden drop in work hardening rate immediately prior to fracture in all specimens, (ii) some specimens exhibited Portevin-Le Chatelier (PLC) effect, (iii) the stress where the PLC effect started increased with yield strength, (iv) the unitless Kocks-Mecking parameter, K. decreased with increasing solution treatment time, and there was a strong relationship between K and elongation (v) the main benefit of prolonged solution treatment of cast aluminum alloys is healing of structural defects, namely oxide bifilms. These results are discussed in detail in the paper.

For a number of steelmakers, Ultra Low Carbon (ULC) steel is one of the major products of high quality steels. The slab of the ULC steel is produced by a continuous casting process in order to maximize the process efficiency. Ti is one of the important alloying elements of the ULC steel in order to secure a good formability of the steel as it is used for outer panels of automobiles. It has been a long problem that an increase of Ti content in the steel increases the extent of nozzle clogging during the continuous casting process. In the present study, the clogging phenomena for the Ti-ULC steel is reviewed, and a possible source of the formation of the clogging material is discussed. Particular attention has been paid to the interfacial reaction between the Ti-ULC steel and the refractory material used for a submerged entry nozzle. A phase diagram of the steel-refractory system is applied to figure out which types of materials are formed and how Ti affects the formation of such a material at the interface between the steel and the refractory.

To investigate the hydrogen mobility in high-manganese twinning-induced plasticity (TWIP) steels, high-temperature permeation tests were conducted. They showed that the addition of aluminium to TWIP steel decreases the permeability and diffusivity of hydrogen and increases the solubility, which implies that one of the effects of aluminium in suppressing the hydrogen-induced mechanical degradation comes from a reduction in hydrogen mobility. The findings on diffusivity and solubility are consistent with an earlier calculation that considered aluminium–hydrogen interactions.

Continuously intensifying aquaculture demands reductions in pathogen infections without increased therapeutics use. A potential solution is the use of prebiotic feed additives like β-glucan and mannan oligosaccharides (MOS). This study focusses (1) on the effect of prebiotics glucan/MOS on growth and fitness of Starry flounder and (2) on the viability of Starry flounder as an aquaculture candidate (as it is considered in South Korea). Over 56- days, juvenile Starry flounder were fed with glucan/MOS enhanced diet and a control diet. Feeding behavior, growth rate, morphological and blood physiological parameters were monitored. Fish fed glucan/MOS enriched diets exhibited significantly increased growth over the experimental period (GLM, p

The effects of melt quality and the placement of a filter in the filling system on Weibull distributions of tensile strength and elongation of Al–7%Si–Mg alloy castings were investigated. Three different combinations of melt quality and filtering were used: (a) unstirred, with filter in the filling system, (b) stirred to produce and entrain surface oxide films with no filter in the filling system to emulate poor initial melt preparation and melt handling, and (c) stirred and with a filter placed in the filling system. The results showed that the highest elongation and tensile strength values were obtained from the unstirred, filtered condition and lowest values were from stirred and unfiltered castings. Statistical analysis of tensile data showed that (i) producing and entraining new surface oxides resulted in a significant reduction in tensile strength and elongation, (ii) the distribution of tensile properties was Weibull for unstirred, filtered and stirred, unfiltered castings, and (iii) tensile strength and elongation of stirred and filtered specimens followed bi-Weibull distributions. By introducing a filter into the filling system, the damage caused by stirring can be only partially remedied. The filter is 72% effective in preventing very large old oxide bifilms from entering the mold cavity but overall the filter was found to be incapable of eliminating the damage given to the metal by stirring.

Double oxide films (hereafter: oxides), inclusions and Fe-rich phases are known to be the most detrimental defects in cast Al–Si–Mg alloys. The effects of these defects on reproducibility of tensile properties in Al–7Si–0.35Mg alloy have been investigated in this study. Four different casting conditions (low oxide—low Fe, high oxide—low Fe, low oxide—high Fe and high oxide—high Fe) were studied. In each case, 30 tensile test samples were prepared by casting in a metallic mold and machining (total of 120 tensile test samples). Results of tensile test were analyzed by Weibull three-parameter and mixture analyses. The microstructure and fracture surface of samples were studied by optical and scanning electron microscopes. Total of 800 metallography images (200 images for each experiment) were taken and analyzed by image analysis software. Finally, the relationship between tensile properties and defects characteristics was discussed. According to the results, Fe (Fe-related phases) had larger negative impact on tensile properties of the alloy compared to oxides. On the other hand, Weibull analysis revealed that the scattering of tensile properties was mainly due to the presence of oxides in microstructure. Results of image analysis showed that the shape factor and number of pores were mainly controlled by oxides and Fe, respectively. Also, there was a clear relationship between Weibull modules of UTS and El% and shape factor of pores. Furthermore, tensile properties of the examined alloy showed strong dependence to the number of pores.

Gas porosities and entrapped double oxide film (hereafter: oxides) are known to be the most detrimental defects in cast Al–Si–Mg alloys. This study investigated the effects of dissolved hydrogen (hereafter: H) and oxides on reproducibility of tensile properties in Al–7Si–0.35 Mg alloys. Also the effects of H and oxides content on the morphology of defects were studied. Four different casting conditions (low oxide–low H, low oxide–high H, high oxide–low H, high oxide–high H) were tested using tensile test bars that were cast in a metallic mold. Results of tensile test that were obtained for each casting condition were analyzed using Weibull two-parameter analysis. Microstructure and fracture surface of samples were examined by optical microscopy, SEM and EDS. Results showed that H has slightly larger negative impact on tensile properties of this alloy compared to oxides. On the other hand, oxides caused considerably higher scattering of tensile properties than H. Examination of microstructure showed that increasing of initial H of melt changed morphology of oxides from two dimensional (2-D) to three dimensional (3-D) one. It was explained through the diffusion of H into the atmosphere of oxides that expanded them. The effects of this morphological change on Von Mises stress and equivalent plastic strain was simulated by using finite element analysis. Results of finite element analysis showed that the maximum values of both Von Mises stress and equivalent plastic strain around the oxides decreased with changing their morphology from 2-D to 3-D. Also, it was shown that increasing of the H in high oxide samples, decreased the average tensile properties of test bars, but increased the reproducibility of tensile properties.

Cathodically charged twinning-induced plasticity (TWIP) steel was evaluated to determine the effects of brief hydrogen charging on the tensile properties. Ductile fracture mechanisms and bulk tensile properties were unaffected by hydrogen contents of up to 9.5 ppm. However, surface microcracks were observed to depths comparable to calculated hydrogen penetration depths, up to 6 μm for samples charged for 6 h. These results highlighted the limited applicability of using pre-charged tensile samples to assess the potential for delayed cracking of austenitic TWIP steels.

5′-adenosine monophosphate-activated protein kinase (AMPK) has been considered as a therapeutic target for the treatment of metabolic syndrome including obesity and type 2 diabetes. In our program to search new AMPK activators from plants, we found that a total extract of Myristica fragrans (nutmeg) activated the AMPK enzyme in differentiated C2C12 cells. As the major constituents of nutmeg, seven lignans, (1) macelignan; (2) meso-dihydroguaiaretic acid; (3) (+/−)-trans-dehydrodiisoeugenol; (4) nectandrin B; (5) licarin A; (6) otobaphenol; and (7) myristicin, were isolated from this extract. It has been well known that myristicin is a principal aromatic constituent of M. fragrans, and its overdose intake in human causes severe psychopharmacological effects. Thus, the processing condition for preparing of extract with active ingredients on AMPK from nutmeg and the method for reducing myristicin content in active ingredients were also studied. PRACTICAL APPLICATIONS Nutmeg (Myristica fragrans Houtt.), which refers to the dried kernels of this plant, has long been indigenously used as a spice in many Western foods. Our research on chemical constituents and biological activity of nutmeg identified six main constituents and nectandrin B as 5′-adenosine monophosphate-activated protein kinase activator. However, because an ingestion of 1–2 mg myristicin/kg body weight causes severe intoxications and psychiatric effects, the use of nutmeg extract for development as functional food was hampered. Thus, simple processing procedure for reducing myristicin content in this extract was studied for it to be used as a functional food of this extract for the treatment of metabolic syndrome containing type 2 diabetes and obesity.

Remineralization of demineralized dentin lesions adjacent to glass-ionomer cements (GICs) has been reported in the literature. This study tested the hypothesis that a strontium-based GIC can remineralize completely demineralized dentin by nucleation of new apatite crystallites within an apatite-free dentin matrix. Human dentin specimens were acid-etched, bonded with Fuji IX GP, and immersed in a calcium-and-phosphate-containing 1.5X simulated body fluid (SBF) for 1-4 months. Polyacrylic acid and polyvinylphosphonic acid biomimetic analogs were added to the SBFs to create 2 additional remineralization media. Specimens were processed by transmission electron microscopy (TEM). No apatite deposition could be identified in the completely demineralized dentin in any of the specimens immersed in the 3 remineralization media, despite TEM/EDX evidence of diffusion of ions specific to the strontium-based GIC into the demineralized dentin. The hypothesis was rejected; mineral concentration alone is not a sufficient endpoint for assessing the success of contemporary remineralization strategies., published_or_final_version

Quality characteristics and yield of 'Maehyang' and 'Seolhyang' strawberry cultivars, which have been registered in Korea, as affected by water stress (WS) was investigated. The total contents of carbohydrates (TC; fructose, glucose, and sucrose), organic acid (TOA; citric, malic, and oxalic acids) and antioxidants such as anthocyanin (AC), ascorbic acid (AA), and ellagic acid (EA) in the fruits were analysed. Yield of 'Seolhyang' was significantly greater than that of 'Maehyang' both in WS and control treatments. The yield of both cultivars decreased in WS treatments by 13.1 and 13.6%, respectively, in comparison with control treatments. In control treatments, TC, AC, and AA were greater, while TOA was inferior in 'Maehyang' than 'Seolhyang' throughout the experimental period. Since TOA increased in 'Maehyang' but decreased in 'Seolhyang', while TC did not change both in both cultivars, carbohydrate-organic acid ratio decreased in 'Maehyang' but increased in 'Seolhyang' in WS treatments. On the other hand, significant differences in AC, AA, and EA as affected by WS treatment were not found in both cultivars except that AC in both cultivars increased at the early starts of harvest. Results indicate that WS treatment is not an appropriate method to improve the quality without decrease in yield for strawberry cultivation even though the contents of antioxidants increased in an early period after being water stressed.

Polypropylene substrate with hair-like nano features(aspect ) on the surface is fabricated by injection molding process. Pure aluminum plate is anodized to have nano pore array on the surface and used as a stamper for molding nano features, The size and the thickness of the stamper is and 1mm. The fabricated pore is about 120nm in diameter and 1.5 um deep. For molding of a substrate with nano-hair type of surface features, the stamper is heated up over before the filling stage and cooled down below after filling to release the molded part. For heating the stamper, stamper itself is used as a heating element by applying electrical power directly to each end of the stamper. The stamper becomes cooled down without circulation of coolant such as water or oil. With this new stamper heating method, nano hairs with aspect ratio of about 10 was successfully injection molded. We also found the heating & cooling process of the stamper is good for releasing of molded nano-hairs.

Aim To evaluate the changes in serum creatinine and total CO 2 levels in patients receiving metformin during administration of contrast medium. Materials and methods Patient records from January 2012 to December 2012 after the administration of contrast medium were reviewed retrospectively. A total of 924 patients were included for the final analysis. Of them, 105 received metformin during contrast medium administration, 112 were taking other oral hypoglycaemic agents, and 707 patients were not diabetic (controls). Results No significant change in total CO 2 levels was detected ( p =0.678). Metabolic acidosis was present in 33 (31.4%) metformin users, 31 (28.6%) other oral hypoglycaemic agent users, and 153 (21.6%) control patients. In the present logistic regression analysis, age, baseline levels of creatinine, and total CO 2 levels were associated with metabolic acidosis after contrast medium exposure. Conclusion These data indicate the presence of a coexisting risk factor, other than metformin use, associated with metabolic acidosis after contrast medium exposure. No relationship was found between the use of metformin and metabolic acidosis during contrast medium exposure.

Peripheral blood (PB) is known as a source of mesenchymal stem cells (MSCs), as is bone marrow (BM), and is acquired easily. However, it is difficult to have enough MSCs, and their osteogenic capacity with dental implantations is scarce. Therefore, we characterized peripheral blood mesenchymal stem cells (PBMSCs) cultured on a bone marrow–derived mesenchymal stem cell (BMMSC) natural extracellular matrix (ECM) and demonstrated the osteogenic capability in an experimental chamber implant surgery model in rabbits. We isolated PBMSCs from rabbits by culturing on a natural ECM-coated plate during primary culture. We characterized the PBMSCs using a fluorescence-activated cell scanner, cell proliferation assay, and multiple differentiation assay and compared them with BMMSCs. We also analyzed the osteogenic potential of PBMSCs mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) by transplanting them into immunocompromised mice. Then, the mixture was applied to the canals. After 3 and 6 wk, we analyzed new bone (NB) formation inside the chambers using histological and histomorphometric analyses. The PBMSCs had a similar rate of BrdU-positive cells to BMMSCs, positively expressing CD90 but negative for CD14. The PBMSCs also showed osteogenic, adipogenic, and chondrogenic ability in vitro and osteogenic ability in vivo. Histological and histomorphometric results illustrated that the PBMSC and BMMSC groups showed higher NB than the HA/TCP and defect groups in the upper and lower chambers at 6 wk and in the upper canal at 3 wk; however, there was no difference in NB among all groups in the lower canal at 3 wk. The PBMSCs have characteristics and bone regeneration ability similar to BMMSCs both in vitro and in vivo. ECM was effective for obtaining PBMSCs. Therefore, PBMSCs are a promising source for bone regeneration for clinical use.

The relationship between the yield ratio and the material constants,b andN, of the Swift equation for hotrolled low carbon steels has been established. The yield ratio calculated by using the Swift equation agrees well with an experimentally obtained yield ratio. It was found that the yield ratio decreases with an increasing value ofN or with a decreasing value ofb. It was also found, however, that high yield strength is associated with small values of bothb andN. Therefore, to obtain both high yield strength and low yield ratio, a detailed microstructural control is needed to determine the optimum values ofb andN.

Directional solidification experiments were conducted in commercial Fe–18Cr stainless steels with 0, 3, 5 wt.% Al contents. The unique feature of this alloy system is the narrow freezing range that causes microstructure transitions to occur at relatively low solidification rate which can be achieved by using the directional solidification technique. The velocity range over which dendrites form was found to decrease, whereas the velocity range over which high-velocity cells were present increased significantly, as the aluminum content of the alloy was increased. The transition conditions for dendrite to high-velocity cells were investigated. Cellular and dendritic spacing variation with velocity was also characterized, and the cell spacing was found to vary continuously with growth rate for the low and high-velocity cells. Based on these results, theoretical models are discussed to characterize microstructure transitions from planar to cellular and from dendritic to high-velocity cellular microstructures.

Pasteurized mushrooms had firmer texture and lighter color compared with those that were retorted. Addition of acid and retorting temperature resulted in extensive softening of mushrooms and solubilization of proteins and polysaccharides that diffused into brine. Total chitin was not affected by applied treatments and did not appear to be related to texture alteration of processed mushrooms. Extensive solubilization caused by acidification and retortion resulted in reduction of cell diameter and enlarged intercellular space within the cap tissue. Mild acidification of sterilized samples reduced discoloration compared with the control, but further acidification resulted in considerable darkening. In contrast, tissue and color of pasteurized mushrooms seemed to be unaffected.

Two experiments were conducted to investigate the effect of dietary supplementation of plant phytase (Phytazyme) in corn-soybean meal based diets on utilization of phytase-bound phosphorus in laying hens and evaluate nitrogen(N) digestibility and phosphorus(P) availability in breeders. In the experiment one, three levels of the Phytazyme(0.05, 0.1, and 0.2% of diet) were added to diets containing a half of control TCP level(0.96%) for 4 wks. Feed consumption, egg production rate, egg weight and eggshell quality were recorded weekly. At the end of experiment, 8 birds per treatment were sacrificed, liver weight were weighed and right tibiae were removed for determination of P content. The second experiment was conducted to evaluate the P availability and nitrogen digestibility in breeders fed same diets for 2 wks. Feed and excreta were collected to determine the P and N contents for the last three days of experiment two. Addition of Phytazyme resulted in no effects on feed intake, egg product rate, egg weight and egg shell quality. P excretion decreased and its availability enhanced as phytase supplementation increased in diets. Dietary supplementation of Phytazyme above 0.1% level in corn-soybean meal based diets did not have an adverse effect on production and decreased level of phosphorus in excreta.

Hot cracking formation and its mechanism in invar alloys (Fe-36mass%Ni) during continuous casting was investigated. The invar alloy is very sensitive to hot cracking due to its low transition tempe ...

During the maintenance of bone marrow-derived mesenchymal stem cells (BMMSCs), suspended cells are discarded normally. We noted the osteogenic potential of these cells to be like that of anchorage-dependent BMMSCs. Therefore, we characterized suspended BMMSCs from rabbit bone marrow by bioengineering and applied the suspended BMMSCs to double-canaled dental implants inserted into rabbits. After primary isolation of BMMSCs, we collected the suspended cells during primary culture on the third day. The cells were transferred and maintained on an extracellular-matrix-coated culture plate. The cells were characterized and compared with BMMSCs by colony-forming-unit fibroblast (CFU-f) and cell proliferation assay, fluorescence-activated cell sorter (FACS), in vitro multipotency, and reverse transcription polymerase chain reaction (RT-PCR). We also analyzed the osteogenic potential of cells mixed with hydroxyapatite/tricalcium phosphate (HA/TCP) and transplanted into immunocompromised mice. We compared the viability and proliferation of the suspended BMMSCs and BMMSCs on the titanium implant surface and observed cell morphology. Then, the cells mixed with HA/TCP were applied to the double-canaled implants during installation into rabbit tibia. Four weeks later, we analyzed bone formation inside the canal by histomorphometry. The suspended cells showed higher CFU-f on the extracellular matrix (ECM)-coated culture plate and similar results of proliferation capacity compared with BMMSCs. The cells also showed osteogenic, adipogenic, and chondrogenic ability. The suspended cells showed levels of attachment survival and proliferation on the surfaces of titanium implant discs to be higher than or similar to those of BMMSCs. The suspended cells as well as BMMSCs showed stronger bone formation ability in both upper and lower canals of the implants compared with controls on double-canaled implants inserted into rabbit tibia. In this study, we showed that suspended cells after primary BMMSC isolation have bone regeneration capacity like that of BMMSCs, not only in vitro but also in vivo. ECM was valuable for propagation of MSCs for cell-based bone regeneration. Therefore, the suspended cells could also be useful tools for bone regeneration after implant surgery.

Two independent energy transfer mechanisms through electric multipole interactions between donor and acceptor ions have been found in BaAl 12 O 19 : Ce 3+ 0.06 + Eu 2+ x phosphor. The first energy transfer takes place between the Ce 3+ ion and the Eu 2+ ion which strongly depends on the concentration of Eu 2+ ions. The second energy transfer occurs between the Ce 3+ ion and the Ce 3+ -O Me complexes. Both energy transfer mechanisms were explained in terms of combined electric multipole interactions.

Magnetoresistivity measurements are made on the two-dimensional electron gas in a Si/Si 0.7 Ge 0.3 modulation-doped quantum well. The temperature (T)-dependent negative magnetoresistivity, observed below 0.1 T, clearly shows the effect of electron-electron interactions.

Diluted juice of paprika was heated at 80, 90 and 100°C with holding times of 0, 2, 4, 8 and 16 min. Capsanthin in each sample was determined by HPLC. The degradation kinetics of capsanthin was studied by two groups of reaction models including elementary reaction rate models and those of modified square root-based pseudo (MRBP-). The MRBP-1st order reaction rate model was proven as an appropriate model in this study. The pseudo Q10 (PQ10) value was 1.045 and the predicted half-life (capsanthin 2,850 mg/L) was 27.47, 21.23 and 15.23 min, respectively, at 80, 90 and 100°C.

Modulation doped n-type Si/Si0.7Ge0.3 quantum wells exhibited the integer quantum Hall effect at integer filling factor ν=2,3,4,5,6,8,10,… Odd-integer filling factors showed the two-fold valley splitting, while even-integer filling factors indicated inter- and spin splitting. From an analysis of the thermally activated resistivity as a function of the magnetic field in the quantum Hall regime we deduced the energy gaps of Landau level and pre-exponential factor. The ratio of the transport relaxation time to the quantum relaxation time (∼9) indicated that the dominant scattering mechanism was long-range remote ion scattering.

Not only the filament surface of chitosan fibre but also its inside was N -acylated at a solid state by treatment with a series of carboxylic anhydrides in methanol at room temperature, and novel N -acylchitosan fibres (d.s. 0.8–1.1 for NAc) were obtained. Their filament tenacity and elongation values were little influenced by the N -acylation. Each of chitin fibre and chitin–cellulose blended fibre was treated with aq. 40% NaOH at 95–100°C for 4 h at a suspension state, and a chitosan fibre and a novel cellulose–chitosan blended fibre were obtained. The relative hydrolysis rate of N -acetyl, N -propionyl and N -butyrylchitosan fibres by an egg-white lysozyme were 1.0:0.3:0.0 at a suspension state. A SEM observation revealed a scaly pattern on the surface of the N -octanoylchitosan filament.

Photoluminescence characteristics and the energy transfer between Ce3+ and Eu2+ in CaAl12O19 host lattice have been investigated. A series of concentrations of Ce3+ ion with a fixed Eu2+ concentration in doubly doped CaAl12O19 : Ce3+Eu2+ have been studied. The indirect energy transfer has been observed between Ce3+ and Eu2+ through the Ce3+OMe complex in CaAl12O19 host lattice. The two nonradiative relaxation processes from the excited levels of Ce3+OMe complex; one, to the lower emitting level of Ce3+OMe complex themselves and the other, to the Eu2+ site are competing processes.

We have constructed charged particle detectors using high quality CVD diamond. We report here the measurements of a diamond-tungsten sampling calorimeter and a diamond mustrip detector. The energy response and resolution (σEE) of the calorimeter were measured using an electron beam of energy 0.5 to 5.0 GeV, and compared with those from a silicon calorimeter of similar construction. We find σEE = (4.7 ± 2.7)%/E ⊕ (19.13 ± 0.86)%/√E ⊕ (2.3 ± 1.8)% for the diamond-tungsten calorimeter, where ⊕ indicates addition in quadrature, which is in good agreement with our result of σE/E = (3.89 ± 0.87)%/E ⊕ (19.73 ± 0.19)%/√E ⊕ (0.0 ± 1.6)% for the silicon-tungsten calorimeter. The CVD diamond mustrip detector consists of 50 μm wide strips on 100 μm centers. A signal-to-noise ratio of 6: 1 and a position resolution of 25 μm was observed during recent accelerator tests.

In searches for rare phenomena such as elastic scattering of dark matter particles or neutrinoless double beta decay, alpha decays of Rn222 progenies attached to the surfaces of the detection material have been identified as a serious source of background. In measurements with CsI(Tl) scintillator crystals, we demonstrate that alpha decays of surface contaminants produce fast signals with a characteristic mean-time distribution that is distinct from those of neutron- and gamma-induced events., 9 pages, 8 figures

Surface energy and hydrophilicity of implant surfaces have been known to play an important role in subsequent cellular responses on the implant surface. The aim of the present study was to evaluate the effects of biomimetic deposition of anodized surfaces on surface wettability, surface energy, and osteoblast responses. Ti discs with 2 different surface topographies (machined and anodized) were immersed in Hanks’ balanced salt solution (HBSS) and modified simulated body fluid (SBF) solution for 2 weeks at physiologic conditions of 37°C, initial pH of 7.4, and p(CO2) of 0.05 atm. Scanning electron microscopic (SEM) observation and energy-dispersive spectroscopic (EDS) microanalysis showed the deposition of calcium phosphate (CaP) onto anodized Ti surfaces immersed in modified SBF. Surface energy, surface wettability, and osteoblast responses, including cell attachment capacity, cell proliferation rate, and cell differentiation level, significantly increased on anodized Ti surfaces immersed in modified SBF. The effects of biomimetic deposition with modified SBF on physiochemical surface characteristics and cell biological responses were greater on anodized surfaces than on machined surfaces. These results indicate that biomimetic deposition with effective SBF may enhance the interaction between anodized Ti surfaces and their biological environment, consequently improving bone healing of dental Ti implants.

A search for charm production in the coherent diffractive dissociation reaction pSi→XSi was carried out for the modes D0→K−π+, D0→K−π+π+π−, and D+→K−π+π+. No charm signals were observed, and the 90% confidence level upper limit for coherent charm pair production was determined to be 26 μb per silicon nucleus. The results are interpreted as an upper limit of 0.2% on the amount of intrinsic charm in the proton.

In this study, we investigated the application of human embryonic stem cells (hESCs) to neural tissue engineering. hESCs were differentiated to neural progenitor cells and cultured on poly(lactic-co-glycolic acid) (PLGA) microfibers. PLGA microfibers were prepared by using a microfluidic spinning system and aligned in parallel manner by winding the nascent fibers around a rotating frame. Neural progenitor cells were prepared by differentiating embryoid bodies (EBs). Neural progenitors cultured on the PLGA fibers were assessed for further proliferation and differentiation. To verify the expression of neural progenitor markers, cells were immunostained with neuronal specific antibodies. After six-days in culture, neuronal protein expression was confirmed with neuron specific beta III tubulin antibody (Tuj1) and glial fibrillary acidic protein (GFAP). After 20-days, cells were immunostained with microfilament associated protein (MAP) and neurofilament. The neurites of differentiated cells cultured for 20 days elongated along the direction of the PLGA microfibers. This result shows the possibility of using PLGA microfibers for neural tissue regeneration as a guidance cue for hESC derived cells.

In this paper, we introduce a densely packed array of floating gate field effect transistors integrated on a silicon chip (FG-FET) used for recording electrical signals from electrogenic cells and stimulating them. The chip called CALIBUR was manufactured using a commercial 2 poly - 3 metal CMOS process. Further post processing for the optimization of the capacitive coupling between the cells by using thin film high-k materials and chip encapsulation were performed in house. The post-processing step includes the development of a lift-off process for the deposition of Pt as a base layer for the high-k materials and the actual deposition of the high-k materials.

We investigate the caesium concentrations in soils in mountain areas near Gori nuclear power plant in Korea, focusing on the measurement limits to the 134Cs. In order to lower the minimum detectable amount (MDA) of activity for the 134Cs, we have used the ammonium molybdophosphate (AMP) precipitation method to get rid of the 40K existing in natural radioactivity, which reduces the MDA activity about 10 times smaller than those without the AMP precipitation method. The MDA results for the 134Cs were found to be in the range between 0.015 and 0.044 Bq/kg-dry weight. In order to diminish the background, we also have measured a part of the soil samples in Yangyang, a small town in the east coast of Korea. However, it turns out that in order to detect the 134Cs in the samples the MDA should be reduced to the level of mBq/kg-dry weight.

We report significant crosstalk reduction between two transistor planes in 3D integrated circuits (3D ICs) using tungsten ground plane structures as the isolation layer. Simulation and experimental results show /spl sim/8 dB of crosstalk attenuation. A significant conclusion of our study is that a ground plane that physically shadows the region it is isolating is optimum for deriving most of the benefits of isolation. We also show that for ground planes composed of standard MOS metallizations, i.e. W, Al, Cu, similar crosstalk isolation is expected. The inter-device ground plane structures have potential to be standard isolation technology for 3D mixed-signal and RF integrated systems due to simple fabrication and significant crosstalk attenuation.

Fabrication techniques that allow wafer-scale transplantation, bonding and interconnecting of fully fabricated device layers with thickness on the order of micrometers are described. The temperature budget of this 3D integration technology is less than 350 /spl deg/C and the approach utilizes Benzocyclobutene (BCB) as the permanent wafer bonding medium. Alignment registration of several micrometers between donor device layer to the host substrate is achieved. The characterization of devices, structures and process conditions are presented. Also, measurement of heating effects and temperatures in a 3D IC environment is described. The 3D integration approach allows reduction in crosstalk for mixed-signal applications using inter-device layer ground planes. This technique shows -8 dB of crosstalk attenuation between device layers. The newly developed 3D integration fabrication methodology can be extended beyond silicon-based devices to SiGe and III-IV technologies.

Summary form only given. Transparent conductive oxide (TCO) is indispensable as the front electrode for most thin film solar cells. Aluminum-doped zinc oxide films (ZnO:Al) were prepared by RF magnetron sputtering on glass (Corning 1737) substrates as a function of the deposition condition. This system has three targets to enable simultaneous sputtering. One of them was a 4 inch disk type ZnO (99.9% purity) target doped with Al/sub 2/O/sub 3/ (2.5 wt%). The distance between substrate and target was kept at 5 cm. The substrates were first loaded in the load-lock chamber and then carried forward into the main chamber. The substrates were heated in the temperature range of 300-673 K using a halogen lamp and also were rotated using a motor in order to get uniform ZnO:Al films. During the film growth the argon gas pressure was maintained in the range of 0.3-10 mTorr. It was observed that the deposition rate and the grain size were decreased and the surface roughness and the etch rate were increased with the increase of argon pressure. The deposited films were found to be smooth with excellent electrical properties (/spl rho/=1.9/spl times/10/sup -4/ /spl Omega/cm) and high transmittance (>80%) in the wavelength of 400-800 nm. Also, spectral haze (T/sub diffuse//T/sub total/), an indicator of the scattering properties of the etched ZnO:Al films, of above 70% could be achieved at wavelengths of 400-800 nm. The surface morphology and thereby the light scattering properties of the sputtered films were found to vary over a wide range as a function of substrate temperature and gas pressure. At low pressures (/spl les/2 mTorr) and high substrate temperatures (>573 K), the surface morphology of the films exhibited a more dense and compact structure with effective light-trapping, suitable for the fabrication of thin film silicon solar cells.

A successful wafer-scale device layering process for fabricating three-dimensional integrated circuits (3D ICs) using Benzocyclobutene (BCB) is described. In the reported embodiment of the method, a sub-micron thick “donor” device layer is transplanted onto a fully fabricated “host” wafer with BCB as the intervening medium. Experimental results, including RIE study and planarization of BCB processed through the 3D fabrication procedure are reported. We conclude with an approach to alleviate BCB and fabrication induced wafer bowing, which leads to poor wafer to wafer alignment in 3D integration.

Intra-arterial injection of neuropeptide Y (NPY) (1.3-2.0 micrograms/kg) resulted in decreases of pulpal blood flow by 37.7 +/- 5.7% (mean +/- SEM). The intra-arterial injection of D-myo-inositol-1,2,6-trisphosphate (PP56) (0.3 mg/kg) alone changed pulpal blood flow by 1.0%. The effect of NPY in the presence of PP56 resulted in significantly smaller decreases in pulpal blood flow ranging from 27.2 +/- 5.4 to 16.6 +/- 3.5% from control as compared with NPY alone. In effect, PP56 partially blocked the decreases in pulpal blood flow caused by NPY. The electrical stimulation of the sympathetic nerve alone resulted in decreases in pulpal blood flow of 41.7 +/- 6.2%. The electrical stimulation of the sympathetic nerve following the intra-arterial administration of PP56 decreased pulpal blood flow by 23.1 +/- 6.0% from control, significantly less than the sympathetic nerve stimulation alone. PP56 attenuated the decrease in pulpal blood flow caused by the sympathetic nerve stimulation by 44.4 +/- 11.0%. Similarly, the combination of PP56 and phentolamine followed by electrical stimulation of the sympathetic nerve reduced the decrease in pulpal blood flow caused by the sympathetic nerve stimulation alone by 43.0 +/- 8.6%. These results provide evidence that the non-peptide PP56 is capable of antagonizing vasoconstriction caused by NPY in the feline dental pulp. In addition, they show functional evidence that NPY as well as noradrenaline are released from the sympathetic nerve endings during its stimulation and cause vasoconstriction.

Summary form only given. We report the photoinduced absorption of oxygen free C/sub 60/ thin film. The thin films of oxygen free C/sub 60/ are produced by evaporation onto sapphire substrate. At energies between 1.65 eV and 2.35 eV, there are two peaks; one at about 1.95 eV and the other at about 2.25 eV which is broader than the former. From the time resolved study of the peak at 1.95 eV, we can conclude that the lifetime of this peak is 40/spl mu/s in the case of oxygen containing film. In the case of oxygen free film, we still can not determine the lifetime of this peak.

Summary form only given. A Polycrystalline films of the ternary semiconducting compound CuInS/sub 2/ have been produced by evaporaion. Single-phase compound CuInS/sub 2/thin films have been made from copper/indium/sulphide stacked layer using heat-treatment in the nitrogen atmosphere. In this paper, The heat-treatment effects of copper/indium/sulphide stacked layer were investigated concretely. And the structual, electrical, and optical properties of compound CuInS/sub 2/thin films were also descrived. Grain size data, especially the consideration of the effects of beat-treatment, are included.

An important initiating step in the induction of tumors is believed to be the covalent binding of an active carcinogenic species to a cellular macromolecule, e.g. DNA. Therefore, a spectroscopic technique which allows for positive identification of the intact (macromolecular) DNA adduct and/or isolated damaged nucleosides/nucleotides is highly desirable. It is shown that fluorescence line-narrowing spectroscopy (FLNS) is a rapid, versatile, highly sensitive and selective analytical technique, which can be used directly to characterize DNA adducts and isolated nucleosides. FLNS possesses sufficient resolution to distinguish between the major DNA adducts derived from different enantiomers of benzo[a]pyrene diol-epoxide (BPDE). With the present limit of detection (approximately 1 adducted base per 10(8) normal base pairs for 100 micrograms of DNA), the technique is applicable to in vivo samples. Analysis of liver DNA from fish exposed to benzo[a]pyrene (BP) (100 mg BP/kg fish) showed that a major DNA adduct is derived from syn-BPDE.

The polycrystalline thin film of single-phase CuInS 2 have been made from Copper/Indium/Sulphide stacked layer at various heat-treatment in the nitrogen atmosphere. The structural and electrical properties of p-type chalcopyrite CuInS 2 thin films were investicated. Resistivity, Hall mobility and concentration of the fabricated CuInS 2 at optimum heat-treatment were 3 × 10 −2 [Ωcm], 0.1 [cm 2 V −1 s −1 ] and 2 × 10 20 [cm −3 ], respectively.

Hot electron noise in short-channel JFETs is measured above 150°K and generation-recombination noise due to donors is measured below 120°K, where it predominates over the first. The hot electron noise increases with increasing VGS - VP for a given temperature T and increasing with decreasing T at a given VGS - VP. The g-r noise in donors increases very rapidly with decreasing temperature and is found to be governed by an activation energy between E0 and 2E0, where E0 is the activation energy of the donors. The theories of these effects can qualitatively explain the data; for the g-r noise it must be taken into account that the activation energy of the donors decreases with increasing electric field (Poole-Frenkel effect).

Light impurity density profiles following hydrogen gas puff and hydrogen pellet fuelling have been obtained via charge exchange recombination spectroscopy on TEXT. After hydrogen pellet fuelling, C+6 and O+8 profiles are more strongly peaked on axis than the electron density profile. In contrast, light impurity profiles measured during sawtoothing high density gas puff fuelled discharges peak to a lesser degree relative to the electrons, with lower central densities than in the pellet case. The shapes of the peaked pellet impurity profiles are well described by neoclassical theory. The measured transport coefficients are larger than neoclassical values. The inferred inward convective velocity is consistent with values measured by impurity injection during sawtoothing discharges, but the diffusion coefficient is an order of magnitude lower than that obtained with impurity injection.

A quantitative description of the higher-lying vibrotational energy levels of diatomic molecules requires going beyond the lowest-order vibron hamiltonian. A systematic expansion to higher orders which is simple to derive and apply is discussed. The essential point is that only such generators of U(4) or powers thereof, that transform under rotation as scalars can appear in the hamiltonian. Higher-order scalars are generated as the products of scalars and scalar products of vectors. The resulting expansion for the rotationally invariant hamiltonian is equivalent to that derived using the spherical tensors formalism. Applications to H 2 are described.