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Previous research provides evidence that individual differences in the personality characteristic of extraversion/introversion can play a significant role in group idea generation. Cognitive stimulation has also been shown to have a significant, though inconsistent, influence on idea generation in computer-mediated groups. We conducted two controlled experiments using a web-based group simulator to empirically test the impacts of these factors on group idea generation. In the first experiment, extraverts outperformed introverts in computer-mediated groups. In the second experiment, we exposed participants in computer-mediated groups to four levels of idea stimulation ranging from none to extremely high. Extraverts generated more unique and diverse ideas than did introverts in moderate- and high-stimuli conditions only. In sum, our study provides empirical evidence regarding the significant effect of individual differences, in this case the personality characteristic of extraversion/introversion on idea generation in a computer-mediated group. We have also demonstrated that a relationship exists between the level of cognitive stimulation and idea generation, with moderate levels of idea stimulation optimal for extraverts in computer-mediated groups. Theoretical and practical implications of these findings are discussed.

InP nanoparticles were formed using a solution method, and the InP nanoparticles that were embedded in a polystyrene (PS) layer were formed using the spin-coating method. The transmission electron microscopy images showed that the InP nanoparticles were randomly distributed in the PS layer. The measured capacitance-voltage (C-V) of the Al/InP nanoparticles embedded in the PS layer/PS/p-Si(100) device at 300 K showed a clockwise hysteresis of the C-V curve. Based on the C-V results, the origin of variations in the memory storage of nonvolatile memory devices that were fabricated using InP nanoparticles embedded in a PS layer due to the scale-down was described.

It has been demonstrated that 5-HT(1A) receptors play an important role in the pathophysiology of schizophrenia. Because Gastrodia elata Bl (GE) modulates the serotonergic system, we examined whether GE could affect phencyclidine (PCP)-induced abnormal behavior in mice. Repeated treatment with PCP increased immobility time, while it decreased social interaction time and recognition memory. PCP-induced abnormal behaviors were significantly attenuated by GE, and these effects were comparable to those of 8-OH-DPAT, a 5-HT(1A) receptor agonist. Furthermore, GE-mediated effects were counteracted by WAY 100635, a 5-HT(1A) receptor antagonist. Our results suggest that the antipsychotic effects of GE are, at least in part, mediated via activation of 5-HT(1A) in mice.

This journal suppl. entitled: Abstracts of the 26th Annual Meeting of the European Society of Human Reproduction and Embryology, Rome, Italy, 27-30 June 2010

Increasing globalization has created tremendous opportunities and challenges for organizations and societies. Consequently, a broad range of information technologies to better support the collaboration of diverse, and increasingly distributed, sets of participants is ever more utilized. Arguably, the success of such technology-mediated collaboration is dependent upon the quality of each individual's contributions; however, although individuals' motivations to do their best could be significantly influenced by the design of a system's human–computer interface, this area has received little attention within the context of group collaboration environments. We fill this gap by integrating research from human–computer interaction, motivation, and technology-supported group work to theoretically derive mechanisms for increasing each individual's motivation within a collective setting. Specifically, we manipulate the interface of a computer-mediated idea generation system (a widely used collaboration tool) to enhance the system's motivational affordance, i.e., the system's properties that fulfill users' motivational needs. Results from two studies demonstrate that by embedding the theoretically derived mechanisms “providing feedback” and “designing for optimal challenge” into the collaboration environment, significant performance gains were realized. The results suggest that even slight manipulations of the human–computer interface can contribute significantly to the successful design of a wide variety of group collaboration environments.

A new synthetic method for the formation of uniform α-Fe2O3 nanoparticles was reported and their magnetic properties were investigated. The sonochemical synthesis and the subsequent take-off technique resulted in spherical shaped α-Fe2O3 nanoparticles with an average diameter of 60 nm. The temperature- and applied magnetic field-dependent magnetization of the α-Fe2O3 nanoparticles was explained by the sum of two contributions, i.e., the Morin transition and superparamagnetism, because the critical size for superparamagnetism was within the size variation of the nanoparticles.

A new well-type neutron counter that is composed of a double-layered annular tube 3 He detector, a polyethylene moderator, and a lead gamma shield has been conceptually designed through an MCNPX simulation. A computer program that generates MCNPX input simulating neutron counterperformance has been developed with 28 parameters to describe the geometrical structure of the neutron counter and source position. The neutron counter has been optimized to have 72.0-cm diameter X 68.3-cm height with a double-layered annular tube 3 He detector of 50-cm length and 2.5-cm thickness through repeated MCNPX simulation with the computer program. The neutron counting efficiency appeared to be >42.4%, and the spatial variance in the sample cavity of the counter was estimated to be

Correlation between gas and dust column density has been studied for the dark globule L1523. The 13CO(J=1→0) emission is used for tracing the gas, and the IR emissions, for tracing the dust constituent. In order to match the beam resolution between the images, a beam de-convolution algorithm based on the Maximum Correlation Method (MCM) was applied on the Infrared Astronomical Satellite (IRAS) data. The morphology of 13CO column density map shows a close correlation to that of 100 μm dust optical depth. The distribution of the optical depth at 100 μm follows that of gas column density more closely than does the flux map at either 60 or 100 μm. The ratio of the 13CO column density to the 100 μm optical depth shows a decreasing trend with increasing dust optical depth in the central part, indicating possible molecular gas condensation onto dust particles. The excessive decrease in the CO column density in the envelope may most probably be due to the photo-dissociation of CO molecules.

We have investigated the role of the grain boundary on the resistive magnetodielectric property of polycrystalline γ-Fe2O3 through impedance spectroscopy measurements. Depending on the sample preparation temperature, the dielectric constant of γ-Fe2O3 is significantly different especially at low frequencies ( 200 K). The value of the magnetodielectric effect at a specific frequency and the resonance frequency for the maximized magnetodielectric effect are different, although polycrystalline γ-Fe2O3 samples show a quite similar magnetoresistance. Through the experimentally obtained resistance ratio between the grain and the grain boundary, we can reproduce the magnetodielectric curves based on the Maxwell–Wagner model and the measured magnetoresistance.

Partial Trisomy- 9q was observed in an infant with a multiple malformation syndrome who survived to 18 months. Cytogenetic investigations stimulated by the family history of similarly affected individuals revealed a translocation, t(9;16)(q32;q24), identifiable in four generations of the proband's family. A review of our cases with those reported in the literature reveals clinical similarities. This report sets forth a clinical description of the characteristic phenotype of the 9q partial Trisomy syndrome, including findings at post-mortem, documents multigeneration transmission and discusses this syndrome's clinical overlap with other malformation syndromes.

We cloned and sequenced two vitellogenin (vg) cDNAs of the carp, Cyprinus carpio, using a cDNA library constructed from estradiol-17β (E2)-treated livers. One was a novel, longer 5000 bp-long cDNA termed vg-B2 encoding 1624 amino acids in a single open reading frame. The other was a shorter cDNA (vg-B1), identical to that registered previously as carp vg cDNA in the international nucleotide sequence database. The deduced amino acid sequences of these two molecules were well-aligned with known vertebrate Vgs sharing common characteristics such as N-terminal lipovitellin I (LVI), phosvitin (PV) and C-terminal lipovitellin II (LVII). The novel Vg-B2 bore a highly conserved GL/ICG motif within the LVII region, in contrast to the shorter Vg-B1 that has a truncated C-terminal and lacks the β-component within the LVII region including the GL/ICG motif. Both vg-B2 and vg-B1 genes were expressed in the livers of females and E2-injected males. Western blot analysis using anti-Vg and anti-vitellin (Vn) antisera demonstrated that both Vg-B2 and Vg-B1 were detected as polypeptides with an estimated molecular mass of 180 kDa and 160 kDa, respectively, in the blood of females and E2-injected males. The results suggest the potential utilization of these genes as sensitive xenoestrogenic markers.

CdTe thin films were grown on GaAs(100) substrates by using molecular beam epitaxy at various temperatures. The results of the X-ray diffraction (XRD) patterns showed that the orientation of the grown CdTe thin films was the (100) orientation. XRD patterns, atomic force microscopy images, high-resolution transmission electron microscopy (HRTEM) images, and photoluminescence spectra showed that the crystallinity of CdTe(100) epilayers grown on GaAs(100) substrates was improved by increasing the substrate temperature. HRTEM images showed that misfit dislocations existed at the CdTe/GaAs heterointerface. These results can help improve understanding of the substrate temperature effect on the structural and the optical properties of CdTe(100)/GaAs(100) heterostructures.

Real-time ultrasound-guided infraclavicular proximal axillary venous catheterization is used in many clinical situations and provides the advantages of catheter stabilization, a reduced risk of catheter-related infection, and comfort for the patient without limitation of movement. However, unintended catheter tip dislocation and accidental arterial puncture occur occasionally. This study was designed to investigate the influence of arm position on catheter placement and complications.Patients were randomized to either the neutral group (n=240) or the abduction group (n=241). In the neutral group, patients were positioned with the head and shoulders placed in an anatomically neutral position and the arms kept by the side during catheterization. In the abduction group, the right upper arm was abducted at 90° from the trunk during catheterization. After real-time ultrasound-guided catheterization was carried out in the right infraclavicular proximal axillary vein, misplacement of the catheter and all complications were evaluated with ultrasound and chest radiography.The success rate of complete catheterization before evaluating the placement of the catheter was high in both groups (97.1 vs 98.8%, P=not significant). The incidence of accidental arterial puncture was not different (1.7 vs 0%, P=not significant). The incidence of misplacement of the catheter was higher in the neutral group than in the abduction group (3.9 vs 0.4%, P=0.01). There were no complications, such as haemothorax, pneumothorax, or injury to the brachial plexus and phrenic nerve, in either group.Upper arm abduction may minimize the risk of misplacement of the catheter during real-time ultrasound-guided infraclavicular proximal axillary venous catheterization.The trial was registered with the Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp. Identifier: KCT0001417.

The three-dimensional electronic structure in the Si inversion layer of nanoscale metal-oxide-semiconductor field-effect transistors (MOSFETs) were calculated by using a self-consistent method. The electronic energy states and the probability density functions in a three-dimensionally confined quantum structure were determined. The energy states strongly depended on the thickness of the thin oxide layer and the applied gate voltage. The few electrons occupying the Si inversion layer significantly affected the electric potential profile of the inversion layer, and a small variation in the oxide thickness dramatically changed the electronic properties in the Si inversion layer. These results can help in understanding the electronic structures in Si inversion layers of nanoscale MOSFETs.

Previous studies have shown that the presence of unerupted mandibular third molars predisposes the mandible to angle fractures. This study attempted to relate the presence of unerupted mandibular third molars with the incidence of condyle fractures. The authors compared the proportion of fractures in 439 patients who had unerupted third molars or no unerupted third molars. Fractures at the condylar region showed a significantly higher incidence in patients without unerupted third molars than in those patients with unerupted third molars. This study provides solid clinical evidence to suggest that the removal of unerupted mandibular third molars predisposes the mandible to condyle fractures.

The initial aim of this study was to examine the expression profiles of P53 and its upstream genes, downstream genes, and cell cycle regulators to determine whether these markers are useful for making a differential diagnosis among the benign, borderline, and malignant ovarian epithelial tumors. Between borderline and malignant tumors, the increased expression levels of P53, Bax, Cyclin E, and cyclin-dependent kinase-2 as well as the decreased expression levels of growth arrest and DNA damage (GADD45) and murine double minute-2 (MDM2) were significantly associated with malignancy (P < 0.01, each). Using the receiver operating curve (ROC), the most reliable cutoff value of the added-up staining scores of those markers was 4.5 with 79% sensitivity and 89% specificity for malignancy. Between benign and borderline tumors, the P21 and Bax expression levels were significantly higher in borderline tumors, whereas the Bcl-2 expression level was much higher in benign tumors (P < 0.01, each). Using the ROC, the cutoff value of the added-up staining scores used to discriminate between the two groups was 2.5 with 70% sensitivity and 74% specificity for borderline tumors. Thus, for the differential diagnosis between borderline and malignant tumors, the cutoff value 4.5 of the cumulative staining scores can be used. However, the cutoff value 2.5 for discrimination between benign and borderline tumors may not be useful because of its relatively low sensitivity and specificity. In addition, the P53, GADD45, Cyclin E, and MDM2 expression levels in malignant ovarian tumors might be useful for determining the histologic grade and type.

Sibutramine is an antiobesity drug that inhibits the reuptake of serotonin and noradrenalin in the hypothalamus. A 37-year-old Korean man presented to the emergency room for the oral intake of 280 mg of sibutramine. The patient was in thyrotoxic state. The 99mTechnetium-pertechnetate thyroid scan showed irregular uptake of radioisotope and thyroid-stimulating hormone receptor antibody and thyroperoxidase antibody were negative. Thyroid function normalized after that. The patient had transient thyrotoxicosis with thyroiditis. We report a case of thyrotoxicosis accompanied by thyroiditis resulting from the intentional overdose of sibutramine.

We have developed a reliable method of microneural anastomosis using cyanoacrylate adhesives. This method involves overlapping the epineuriums of the two nerve ends and then applying two or three microdrops of cyanoacrylate adhesive on the surface of the epineurium just where the epineuriums overlap. The sciatic nerves of Sprague-Dawley rats were transected and repaired either with 10-0 nylon sutures or by using the described method. Histological evaluation showed no significant difference in the outcome of nerve regeneration between the two groups. It was concluded that the cyanoacrylate repair deserves to be considered as an alternative to the conventional suture technique in microneural anastomosis.

In Korea, a speed up test of a train was performed on a high speed railway. The name of the vehicle is HEMU-430x. While the train increased speed from 300km/h to 421km/h on a railway track designed for 350km/h, elastic vertical displacement was measured on the transition zone of bridge-earth in the Gaya overpass bridge. Until the train speed reached 421km/h, the maximum of elastic vertical displacement measured 0.061mm on top of a reinforced roadbed and 0.311mm on top of a HSB (hydraulic stabilized base). Maximum vertical displacement of HSB measured at 383km/h, displacement decreased over 383km/h. Vertical displacement of reinforced roadbed increased according to the increase in train speed.

A process to form a periodically poled polymer film by photoisomerization is described. A poled film of polymethylmetaclyrate containing 5 wt % of 4-(4-nitrophenylazo)aniline (Disperse Orange 3) was exposed to an Ar+ laser beam using a photomask of a 100 μm period grating. Disorientation of the chromophore molecule resulted in decrease of d33 in the photoisomerized domain. Quasiphase-matched second-harmonic generation is demonstrated experimentally using a processed film. Phase-matching was confirmed by tuning the fundamental wavelength around 1200 nm. The effective propagation length due to a tightly focused fundamental wave and the influence of the absorption loss are discussed. The depoling process by photoisomerization is compared with photobleaching, optical poling, and electron beam treatment.

In order to develop inert matrix material, evaluation of physical and chemical properties required for sintered nuclear fuel candidate materials were performed for more appropriate candidate material selection. Active research is being carried out to develop a new inert matrix material, e.g. ZrO2, MgAl2O4, ZrSiO4, and SiC, that prohibits the formation of Pu and actinides. Based on the experimental results, pressureless sintered SiC was considered to be the most appropriate candidate material. Microstructure and thermal conductivity changes were examined of the porous SiC. Effective thermal conductivity decreased by increasing porosity and decreasing the ratio between gas thermal conductivity within pores and sintered material thermal conductivity. With same porosity level, pore size and distribution have little effect on effective thermal conductivity.

Optical conductivity spectra of a cleaved ab plane of ${\mathrm{La}}_{1.2}{\mathrm{Sr}}_{1.8}{\mathrm{Mn}}_{2}{\mathrm{O}}_{7}$ exhibit a small polaron absorption band in the midinfrared region over all temperatures. With decreasing temperature $(T)$ up to Curie temperature ${(T}_{C}),$ the small polaron band moves to a higher frequency, resulting in a finite gaplike feature. However, it shifts to a lower frequency below ${T}_{C}.$ With decreasing T, a stretching phonon mode hardens above ${T}_{C}$ and softens below ${T}_{C}.$ These concurring changes of lattice and electronic structure indicate that short-range polaron correlation exists above ${T}_{C}$ but disappears with the magnetic ordering.

Magnetic-field $(H)$-dependent optical conductivity spectra $\ensuremath{\sigma}(\ensuremath{\omega})$ and dielectric constant spectra $\ensuremath{\varepsilon}(\ensuremath{\omega})$ of a layered antiferromagnet $(A\ensuremath{-}\mathrm{t}\mathrm{y}\mathrm{p}\mathrm{e})$ ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}$ were presented. At 0.0 T in 4.2 K, the $\ensuremath{\sigma}(\ensuremath{\omega})$ showed a small Drude-like peak in the far-infrared region and a broad absorption peak in the mid-infrared region. As H increased, large spectral weights were transferred from high- to low-energy regions with increase of the Drude-like peak. We found that a polaron picture could explain most of the H-dependent spectral changes. By analyzing the H-dependent spectral weight changes and $\ensuremath{\varepsilon}(\ensuremath{\omega}),$ we showed that a dimensional crossover from a two-dimensional to a three-dimensional metal could occur in ${\mathrm{Pr}}_{1/2}{\mathrm{Sr}}_{1/2}{\mathrm{MnO}}_{3}.$

Various zinc dicarboxylate catalysts were synthesized by the reaction of zinc oxide with eleven different glutaric acid derivatives, and their coordination characteristics were investigated by infrared spectroscopy. The electronic nature and steric hinderance of substituents influenced the coordination of the carboxylate and the zinc metal ion. The coordination characteristics were classified into three categories: (i) compounds exhibiting bridging bidentate coordinating bonding modes, such as syn-anti and syn-syn bridging; (ii) compounds with only unidentate coordination; and (iii) compounds with mixed coordinations of unidentate and bridging bidentate. All the zinc carboxylate catalysts produced poly(propylene carbonate)s (PPCs) by the copolymerization of carbon dioxide and propylene oxide. The first category of catalysts produced relatively higher yields than the other categories. Zinc glutarate without any substituent, which is a catalyst in the first category, produced PPC with the highest yield and the highest molecular weight. The catalytic activity of zinc glutarate was suppressed by incorporation of substituents. The suppression of the catalytic activity might be due to the variation in the Lewis acidity of the zinc site as well as changes in the morphological structure caused by the substituents. Methylaluminoxane was also evaluated as a catalyst for the copolymerization, but it produced copolymers containing a large amount of ether linkages.

Linear and nonlinear optical properties of electrically poled films of newly synthesized poly [(4′-acetylphenylaminoformyloxy-4-styrene)-co-(4-hydroxystyrene)] [poly(AS-co-HS)] are investigated. Linear optical properties of a poly(AS-co-HS) film are measured by the prism-coupling method. Ultraviolet (UV) transparency down to 350 nm identifies that this polymer is a promising candidate for second-harmonic generation (SHG) in the UV-visible light region. Corona-poling technique is used to produce a noncentrosymmetric structure. The induced d33 at λ=1064 nm is 2.8 pm/V. High glass-transition temperature (Tg=160 °C) results in very long decay time of the nonlinearity, d33. The decay time at operating temperature of 80 °C is estimated to be more than ten years. Guided-mode blue and green SHGs are demonstrated using the film as a slab waveguide.

Temperature and polarization dependent electronic structure of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ was investigated by optical conductivity analyses. With decreasing temperature, a broad midinfrared peak in the optical conductivity for $E\ensuremath{\Vert}\mathrm{ab}$ of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ becomes narrower and shifts toward a higher frequency, and, furthermore, its optical gap significantly increases. We showed that such a temperature-dependent behavior of ${\mathrm{La}}_{1/2}{\mathrm{Sr}}_{3/2}{\mathrm{MnO}}_{4}$ is the result of cooperative enhancement of the orbital ordering stabilized by the CE-type magnetic ordering and the Jahn-Teller distortion.

We report the exchange bias in antiferromagnet/ferrimagnet Cr₂O₃/Fe₃O₄ core/shell nanoparticles. The magnetic field hysteresis curve for Cr₂O₃/Fe₃O₄ nanoparticles after field-cooling (FC) clearly showed both horizontal (H EB ~610 Oe) and vertical (ΔM~5.6 emu/g) shifts at 5 K. These shifts disappeared as the temperature increased toward the Neel temperature of Cr₂O₃ (T N ~307 K). The H EB and ΔM values were sharply decreased between the 1 s t and the 2 nd magnetic field cycles, and then slowly decreased with further cycling. These results are discussed in terms of the formation of single domains with pinned, uncompensated, antiferromagnetic spin and their evolution into multi-domains with cycling.

A resonant photoemission study has been performed for Pr{sub 1{minus}x}Sr{sub x}MnO{sub 3}thinsp(x=1/3,1/2) and the partial spectral weight (PSW) distributions of both Pr 4f and Mn 3d electrons have been determined. With varying temperature ({ital T}) and {ital x}, metal-insulator transitions are observed in the photoemission data. The Pr ions in Pr{sub 1{minus}x}Sr{sub x}MnO{sub 3} are trivalent, and Pr 4f PSW exhibits a dominant hybridization peak indicating large Pr 4f{minus}Othinsp2p mixing. The Mn 3d PSW at low {ital T} shows a charge gap for x=1/2, and a reduced spectral intensity near E{sub F} for x=1/3, suggesting the localized nature due to the lattice polaron formation. thinsp {copyright} {ital 1999} {ital The American Physical Society}

We investigated temperature-dependent optical conductivity spectra of a ${\mathrm{Nd}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ single crystal. We found that polishing and surface scattering effects on the ${\mathrm{Nd}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ crystal surfaces could significantly distort the optical responses, especially in the mid-infrared region. However, oxygen annealing and gold normalization processes seemed to remedy the distortions. We found that the spectral weight of ${\mathrm{Nd}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ in the metallic state might be composed of a Drude carrier term and a strong incoherent mid-infrared absorptions. The temperature dependence of the spectral weight suggests that the electron-lattice coupling should be important in optical properties of colossal magnetoresistance manganites.

We have mapped a 17 square-degree section () = () of the Galactic Anticenter region in the 12 CO line using the 3-mm SIS receiver on the 14-m telescope at the Taeduk Radio Astronomy Observatory. A total of 7 000 spectra has been obtained with a grid spacing of . The results of the observations are presented in the form of and contour maps. Molecular emission of the mapped area is found to be very extended and matches with the FIR emission boundary. The radial velocity of the molecular gas is found to be within the range of +10 km s -1 . We also found several small clouds located at , having km s -1 , which is quite anomalous in this direction. We identified 30 individual clouds within the mapped region with an arbitrary threshold temperature using a cloud identification code. Twelve subclouds were also identified from the largest cloud with a higher threshold temperature. The ratio of dust emission to CO integrated intensity for the Galactic Anticenter region is found to be similar to that of the dark clouds in solar neighborhood, and much less than that of giant molecular clouds, implying that the heating source within the clouds is minimal.

We investigated temperature-dependent optical conductivity spectra of ${\mathrm{La}}_{7/8}{\mathrm{Sr}}_{1/8}{\mathrm{MnO}}_{3}.$ Its phonon bending mode starts to be splitted near a structural phase-transition temperature. With further cooling, the strength of a midinfrared small polaron peak, which is located at 0.4 eV, becomes increased. These temperature-dependent changes in the phonon spectra and the polaron absorption peaks were explained by a phase separation and a percolation-type transition.

The zero-field ${}^{139}\mathrm{La}$ nuclear magnetic resonance (NMR) was studied in polycrystalline ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ for $0.125l~xl~0.5$ to investigate magnetic phases in ordered states. The main result of this work is that mixed states are found near any phase transition boundary induced by either temperature or hole doping. The analysis of the NMR signal intensity and resonance frequency provides the evidence for ferromagentic clusters or magnetic polarons near the ferromagnetic transition temperature ${(T}_{C}).$ The drastic change of the enhancement factor crossing the phase boundary at $x=0.2$ implies the existence of single domain ferromagnetic microregions imbedded in an antiferromagnetic host for $xl0.2.$ The comparison of NMR signal intensity with bulk magnetization shows that the macroscopic antiferromagnetic phase at $x=0.5$ is a mixed state of microscopic ferromagnetic and antiferromagnetic phases.

Optical conductivity spectra of La_{0.7-y}Pr_{y}Ca_{0.3}MnO_3 were systematically investigated. For metallic samples, the spectral weight below 0.5 eV, whose magnitude can be represented by the effective carrier number N_{eff}(0.5 eV), increases as temperature becomes lower. Regardless of the Pr doping, all the measured values of N_{eff}(0.5 eV)/T_C fall into one scaling curve. This scaling behavior could be explained by the theoretical model by Roeder et al. [Phys. Rev. Lett. 76, 1356 (1996)], which includes spin double exchange and Jahn-Teller lattice coupling to holes. With the Pr doping, far-infrared conductivities were found to be suppressed, probably due to the Anderson localization.

Temperature dependent optical conductivity spectra of a ${\mathrm{La}}_{0.7}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ (LCMO) sample were measured. In the metallic regime at very low temperatures, they clearly showed two types of absorption features, i.e., a sharp Drude peak and a broad midinfrared absorption band, which could be explained as coherent and incoherent bands of a large lattice polaron. Electrodynamic analyses suggest that the elementary excitation in LCMO should be in a strong coupling regime and have interactions with the spin degree of freedom.

Stoichiometric SrTiO3 (STO) films doped with Fe or Cr were prepared by r.f. magnetron sputtering technique. The effects of Fe or Cr doping in the SrTiO3 films were studied on the leakage current property which was discussed by defect chemistry. The experimental results can be explained by a model in which oxygen vacancies are the key defects responsible for the leakage current. Acceptor doping, with a small concentration of Fe or Cr, has led to a substantial improvement to 10−9 order in the leakage current density. Above the concentration of 0.01∼0.02 mol% Fe2O3, Cr2O3, however, as the concentration increased, the leakage current increased. These acceptors in Ti4+ site are expected to electrically compensate for donor species such as oxygen vacancies, thereby reducing the concentration of mobile carriers that contribute to electrical conduction. Consequently, acceptor doped STO films have been shown to be superior to undoped films for applications requiring high leakage resistance, such as dynamic random access memory capacitors. © 1998 Chapman & Hall

Water quality classification for stream has been major tool for water quality management in Korea. This paper examines the application of the fuzzy inference mechanism to develop a fuzzy expert system for proper determination of WQCS from uncertain and imprecise ecological information. This study proposes a rule matrix composed of seven water quality grades, toxicity of water and rarity of cases. From this rule matrix, 30 rules for WQCS determination are generated. From the comparison of performance of the fuzzy expert system and the conventional expert system for the determination of class, toxicity, and rarity, it seems that the smoothly varying curves of WQCS determination from the fuzzy expert system represent our real-world experience more realistically than stepwise curves from the conventional expert system.

Infrared ~IR! reflectivity spectra were measured in temperatures between 160 K and 290 K for polycrystalline La 0.7Ca 0.3MnO3 ~LCMO! samples. Though all the samples showed nearly the same reflectivities, their dc resistivities were varied by more than one order of magnitude. Their resistivities predicted by the HagenRubens relation from the IR spectra were much lower than the values from dc measurements, but they were very close to those of epitaxially grown LCMO films. Our results suggest that dc transport properties of LCMO might be strongly influenced by intergranular resistance, but that the IR responses reflect intrinsic properties of the LCMO grains. @S0163-1829~97!04107-6# Recently, there have been many investigations on perovskite manganese oxides, especially La1-xAxMnO3 ~A is a divalent element such as Sr and Ca! compounds, due to their colossal magnetoresistances. In order to understand origins of such an intriguing phenomenon, it is essential to measure transport properties correctly. However, even for a simple transport property such as a dc resistivity, r, there exists a large variation in reported values. As an example, let us look into the case of La0.7Ca0.3MnO3 ~LCMO!, which has a metalinsulator ~MI! transition at TMI. 250 K. Most reported values of r(TMI) for the polycrystalline bulk samples usually fall into 0.05 ‐ 500 V cm. 1‐4 On the other hand, the reported values of r(T MI ) for LCMO films usually fall into 0.01‐1.0 V cm. 4,5 In spite of such a large variation, little attention has been paid to this problem. The colossal magnetoresistances in the manganese oxides might be related to extrinsic effects such as grain-boundary scattering or to their intrinsic properties. Therefore, it is important to look into the variation in r, and to isolate clearly what the intrinsic properties are. In this paper, we report our systematic studies on dc and infrared ~IR! resistivities of LCMO samples prepared under various conditions.

Recently, jaw size was changed from 4 mm aper- ture (J4) to 1 mm (J1) in TomoTherapy Hi-Art II® (TomoThe- rapy Inc., Madison, WI) to improve the longitudinal (IEC-Y) resolution of megavoltage computed tomography (MVCT) images. This study attempted to conduct a comparative analy- sis on the effect of jaw aperture size of MVCT on image quali- ty and dose. Also, this study investigated the clinical effect of jaw aperture size on highly radiosensitive lens dose. MVCT image quality test (image noise, uniformity, contrast linearity, and spatial resolution) and multiple scan average dose (MSAD) were measured to examine the effect of change in jaw aperture size. A head phantom and photoluminescence glass dosimeters (PLDs) were used to measure exposed lens dose (cGy). For image quality, the change in jaw aperture size did not have a significant effect on image noise, uniformity, con- trast linearity, and spatial resolution although showing slight improvement of image quality. FHWM was 6.7 mm and 4.1 mm in J4 and J1, respectively, which represents enhancement in the longitudinal resolution of MVCT image. MSAD of cen- ter point was approximately 0.69-2.32 cGy (peripheral: 0.83- 2.48 cGy) in J4, and 0.85-2.81 cGy (peripheral: 1.05-2.86 cGy) in J1. The measured lens dose using PLDs ranged 0.92-3.36 cGy and 1.06-3.91 cGy in J4 and J1, respectively, indicating dose increase for the narrower jaw aperture size. An addition- al dose of 3.86 cGy, 1.92 cGy, and 1.22 cGy was delivered for a pitch of 1, 2, and 3, respectively during MVCT scan per frac- tion in head and neck treatment plans. Therefore, 15% in- crease in imaging dose with 1 mm aperture jaw should be allowed for compared to that with previous 4 mm aperture jaw.

Isolated sulfite oxidase (SO) deficiency is an autosomal recessively inherited inborn error of sulfur metabolism. In this report of a ninth patient the clinical history, laboratory results, neuropathological findings and a mutation in the sulfite oxidase gene are described. The data from this patient and previously published patients with isolated sulfite oxidase deficiency and molybdenum cofactor deficiency are summarized to characterize this rare disorder. The patient presented neonatally with intractable seizures and did not progress developmentally beyond the neonatal stage. Dislocated lenses were apparent at 2 months. There was increased urine excretion of sulfite and S-sulfocysteine and a decreased concentration of plasma cystine. A lactic acidemia was present for 6 months. Liver sulfite oxidase activity was not detectable but xanthine dehydrogenase activity was normal. The boy died of respiratory failure at 32 months. Neuropathological findings of cortical necrosis and extensive cavitating leukoencephalopathy were reminiscent of those seen in severe perinatal asphyxia suggesting an etiology of energy deficiency. A point mutation that resulted in a truncated protein missing the molybdenum-binding site has been identified.