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Electric field mapping using segmented detectors in the scanning transmission electron microscope has recently been achieved at the nanometre scale. However, converting these results to quantitative field measurements involves assumptions whose validity is unclear for thick specimens. We consider three approaches to quantitative reconstruction of the projected electric potential using segmented detectors: a segmented detector approximation to differential phase contrast and two variants on ptychographical reconstruction. Limitations to these approaches are also studied, particularly errors arising from detector segment size, inelastic scattering, and non-periodic boundary conditions. A simple calibration experiment is described which corrects the differential phase contrast reconstruction to give reliable quantitative results despite the finite detector segment size and the effects of plasmon scattering in thick specimens. A plasmon scattering correction to the segmented detector ptychography approaches is also given. Avoiding the imposition of periodic boundary conditions on the reconstructed projected electric potential leads to more realistic reconstructions. [ABSTRACT FROM AUTHOR]

• Extensive literature survey on two-phase flow experiment using 12 m or longer vertical tube was conducted. • Experiments were conducted on two-phase flow regime observation, void fraction and frictional pressure drop measurement over a long channel length under high-pressure brine conditions. • The transition of flow regime took place at higher superficial gas velocity under brine conditions. • Through drift-flux model analysis, change in gas velocity under brine conditions was confirmed. • New frictional pressure drop model at high-pressure two-phase flow under brine conditions is proposed. The offshore methane hydrate production test conducted in Japan has demonstrated a successful production of methane gas from marine gas hydrates using depressurization methods. The method produces methane gas by dissociating methane hydrate, which is stable at low temperature and high pressure conditions, by lowering the bottom-hole pressure in the wellbore. Under this method, stable control of bottom-hole pressure is necessary to ensure continuous methane gas production. Therefore, understanding the behavior of upward gas–liquid two-phase flow, involving gas-brine mixture, in a wellbore is essential for the proper pressure drop evaluation in the production line. In the present study, void fraction and frictional pressure drop behaviors under nitrogen-brine two-phase flow conditions is investigated using the high-pressure test facility of 52.7 mm inner diameter and 28 m height. The measured void fraction was assessed using drift-flux model, and the results showed that the decrease in bubble diameter under bubbly flow in gas-brine two-phase flow conditions resulted in decrease in bubble rise velocity and uniformity of bubble distribution. It was also found that, under bubbly flow in gas-brine mixture, the frictional pressure drop tends to further decrease with elevation. Based on these findings and obtained experimental dataset, the new frictional pressure model for gas-brine two-phase flow under high-pressure conditions is developed in the present study. [ABSTRACT FROM AUTHOR]

To correlate atomistic structure with longer range electric field distribution within materials, it is necessary to use atomically fine electron probes and specimens in on-axis orientation. However, electric field mapping via low magnification differential phase contrast imaging under these conditions raises challenges: electron scattering tends to reduce the beam deflection due to the electric field strength from what simple models predict, and other effects, most notably crystal mistilt, can lead to asymmetric intensity redistribution in the diffraction pattern which is difficult to distinguish from that produced by long range electric fields. Using electron scattering simulations, we explore the effects of such factors on the reliable interpretation and measurement of electric field distributions. In addition to these limitations of principle, some limitations of practice when seeking to perform such measurements using segmented detector systems are also discussed. [ABSTRACT FROM AUTHOR]

n alumina (α-AlO) bicrystal with a ( $$ \bar{1} $$104)/[11 $$ \bar{2} $$0] 2 low-angle tilt grain boundary was fabricated by diffusion bonding at 1500 °C in air, and the grain boundary was observed by transmission electron microscopy (TEM). High-resolution TEM observations revealed that the grain boundary consists of at least two kinds of dislocations. One is a perfect dislocation which has a Burgers vector of 1/3[ $$ \bar{1} $$2 $$ \bar{1} $$0]. The other is dissociated into two partial dislocations with a stacking fault on the (0001) plane, and each partial dislocation has a 1/6[ $$ \bar{1} $$101] edge component. It is suggested from structural considerations that the dissociated-dislocation pair originates from a b = 1/3[02 $$ \bar{2} $$1] perfect dislocation (i.e., 1/3[02 $$ \bar{2} $$1] → 1/6[02 $$ \bar{2} $$1] + 1/6[02 $$ \bar{2} $$1]). This dissociation produces a stacking fault in the anion sublattice. The stacking fault energy is estimated to be roughly 1.3 Jm based on the elastic theory. The authors discuss the dislocation structures and the stacking fault formed on the (0001) plane in detail. [ABSTRACT FROM AUTHOR]

Atomic structure of a Σ = 13, [image omitted] grain boundary in α-Al2O3 was directly observed by aberration-corrected Z-contrast scanning transmission electron microscopy. Combining observations from two orthogonal directions parallel to the grain boundary plane [image omitted], the three-dimensional atomic configuration of the grain boundary core region can be determined, and proves to be in a good agreement with the stable boundary structure predicted by first-principles calculations. [ABSTRACT FROM AUTHOR]

Background/Aims: A recent paper reported that the phospholipid transfer protein (PLTP) reduces phosphorylation of tau in human neuronal cells. In addition, patients with Alzheimer’s disease (AD) have significantly higher levels of PLTP in brain tissue and significantly lower PLTP-mediated phospholipid transfer activity in cerebrospinal fluid. PLTP also affects apolipoprotein E (APOE) secretion from glial cells. This study aimed to investigate whether single nucleotide polymorphisms (SNPs) of the PLTP gene are associated with AD. Methods: Five SNPs, genotyped using TaqMan® technology, were analyzed using a case-control study design. Furthermore, we also checked for a synergetic association between the PLTP gene, APOE and AD. Our case-control dataset consisted of 180 AD patients and 130 age-matched controls. Results: None of the SNPs showed a statistically significant association. We could not confirm any synergetic association between the SNPs and APOE in our AD patients. Conclusion: Our results indicate that there is no genetic association between PLTP and AD. Due to the relatively small sample size and the incomplete coverage of the region surrounding the PLTP gene of this study, larger genetic studies covering the entire PLTP gene region are needed. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: We explore the dynamics of image formation in the so-called annular bright field mode in scanning transmission electron microscopy, whereby an annular detector is used with detector collection range lying within the cone of illumination, i.e. the bright field region. We show that this imaging mode allows us to reliably image both light and heavy columns over a range of thickness and defocus values, and we explain the contrast mechanisms involved. The role of probe and detector aperture sizes is considered, as is the sensitivity of the method to intercolumn spacing and local disorder. [Copyright &y& Elsevier]

Abstract: We have investigated the effect of unidirectional periodic potential modulation on the fractional quantum Hall (FQH) states located within the filling factor range . We find that odd-numerator FQH states are strongly suppressed, while the even-numerator ones are less affected or even enhanced, by the introduction of the modulation. In the picture of the composite fermions (CFs), the behaviors are equivalent to the suppression of the spin splitting of the CFs by the modulation. We discuss the origin of the suppression and the possible modulation-induced phase transition from the FQH state to the stripe state. [Copyright &y& Elsevier]

Abstract: An alumina (α-Al2O3) bicrystal with a {1 00}/〈11 0〉 2° low-angle grain boundary was fabricated by diffusion bonding, and the grain boundary was observed by high-resolution transmission electron microscopy (HRTEM). It was found that 1/3〈1 00〉 partial-dislocation triplets were periodically arrayed along the boundary. The atomic structure within the {1 00} stacking faults in between the partial-dislocation triplets was determined by HRTEM combined with first-principles calculations. We discuss the stacking fault structures and their excess energies in detail. [Copyright &y& Elsevier]

Background/Aims: A recent paper reported that the TAR-DNA binding protein (TDP-43) is the disease protein in amyotrophic lateral sclerosis and frontotemporal lobar dementia with ubiquitin-positive inclusions. In addition, it has been shown that TDP-43 may play a role in the pathogenesis of Alzheimer's disease (AD). This study aims to investigate whether single nucleotide polymorphisms (SNPs) of the TDP-43 gene are associated with AD. Methods: Eight SNPs, genotyped using TaqMan technology, were analyzed using a case-control study design including a haplotype analysis. Furthermore, an analysis of the cases divided according to apolipoprotein E (APO E) status was also carried out. Our case-control dataset consists of 181 AD patients and 130 age-matched controls. Results: Although none of the SNPs showed statistically significant association, we identified an association between a specific haplotype (G-A-A-G) of the TDP-43 gene and risk for AD. We could not confirm any synergetic association between the SNPs and APO E in our AD patients. Despite the relatively small sample size, our results indicate a possible genetic association between TDP- 43 and AD. Conclusion: Further genetic studies are needed to clarify the relationship between the TDP-43 gene and AD. [ABSTRACT FROM AUTHOR]

Abstract: Annular dark field scanning transmission electron microscopy imaging was recently applied to a catalyst consisting of gold nanoparticles on (110), showing directly that the gold atoms in small nanoparticles preferentially attach to specific sites on the (110) surface. Here, through simulation, a parameter exploration of the imaging conditions which maximise the visibility of such nanoparticles is presented. Aberration correction, finite source size and profile imaging are all considered while trying to extracting the maximum amount of information from a given sample. Comment is made on the role of the thermal vibration of the atoms in the nanoparticle, the magnitude of which is generally not known a priori but which affects the visibility of the nanoparticles in this imaging mode. [Copyright &y& Elsevier]

Determining the atomic structure of internal interfaces in materials and devices is critical to understanding their functional properties. Interfacial doping is one promising technique for controlling interfacial properties at the atomic scale, but it is still a major challenge to directly characterize individual dopant atoms within buried crystalline interfaces. Here, we demonstrate atomic-scale plan-view observation of a buried crystalline interface (an yttrium-doped alumina high-angle grain boundary) using aberration-corrected Z-contrast scanning transmission electron microscopy. The focused electron beam transmitted through the off-axis crystals clearly highlights the individual yttrium atoms located on the monoatomic layer interface plane. Not only is their unique two-dimensional ordered positioning directly revealed with atomic precision, but local disordering at the single-atom level, which has never been detected by the conventional approaches, is also uncovered. The ability to directly probe individual atoms within buried interface structures adds new dimensions to the atomic-scale characterization of internal interfaces and other defect structures in many advanced materials and devices. [ABSTRACT FROM AUTHOR]

BACKGROUND/AIMS: Recently, it has been shown that the heme oxygenases HMOX1 and HMOX2 might play a role in the pathogenesis of Alzheimer's disease (AD). METHODS: To investigate whether there is any association between the HMOX1 and HMOX2 genes and AD, five single nucleotide polymorphisms (SNPs) in each gene were genotyped in 180 AD patients and 132 age-matched controls using TaqMan technology. RESULTS: Our study failed to detect any association between the SNPs of the HMOX1 and HMOX2 genes and AD. In addition, we did not observe any synergetic association between the SNPs studied and apolipoprotein E in our AD patients. CONCLUSION: Further genetic studies are needed to clarify the relationship between the two genes and AD. [ABSTRACT FROM AUTHOR]

Determining the atomic structures of oxide surfaces is critical for understanding their physical and chemical properties but also challenging because the breaking of atomic bonds in the formation of the surface termination can involve complex reconstructions. We used advanced transmission electron microscopy to directly observe the atomic structure of reduced titania (TiO2) (110) surfaces from directions parallel to the surface. In our direct atomic-resolution images, reconstructed titanium atoms at the top surface layer are clearly imaged and are found to occupy the interstitial sites of the TiO2 structure. Combining observations from two orthogona[ directions, the three-dimensional positioning of the Ti interstitials is identified at atomic dimensions and allows a resolution of two previous models that differ in their oxygen stoichiometries. [ABSTRACT FROM AUTHOR]

Abstract: The dislocation structures of a low-angle tilt grain boundary in alumina bicrystal were investigated by transmission electron microscopy. The grain boundary was found to consist of two regions: an area with pairs of partial dislocations and an area with groups of odd numbered partial dislocations (multiple-partial-structure). Eight kinds of multiple-partial-structures were found in the fabricated grain boundary. The Burgers vectors of each partial dislocation in the grain boundary can be distinguished by dark-field imaging, and thus the arrangement of partial dislocations in the multiple-partial-structures are determined. It is concluded that a slight twist component of the boundary is the origin of the characteristic multiple-partial-structures. [Copyright &y& Elsevier]

Little is known about dislocation core structures in oxides, despite their central importance in controlling electrical, optical, and mechanical properties. It has often been assumed, on the basis of charge considerations, that a nonstoichiometric core structure could not exist. We report atomic-resolution images that directly resolve the cation and anion sublattices in alumina (α-Al2O3). A dissociated basal edge dislocation is seen to consist of two cores; an aluminum column terminates one partial, and an oxygen column terminates the second partial. Each partial core is locally nonstoichiometric due to the excess of aluminum or oxygen at the core. The implication for mechanical properties is that the mobile high-temperature dislocation core structure consists of two closely spaced partial dislocations. For basal slip to occur, synchronized motion of the partials on adjacent planes is required. [ABSTRACT FROM AUTHOR]

Myeloperoxidase (MPO) presence has been demonstrated in microglia associated with senile plaques and contributes to Alzheimer's disease (AD) pathology through oxidation-induced damage. MPO activity is normally higher in women than in men. Additionally, a functional biallelic (G/A) polymorphism in the promoter region (-463) of the MPO gene has been associated with a gender-specific risk factor for AD, but reports of this association have been inconsistent. Furthermore, estrogen is known to enhance MPO activity in myeloid cells and increases the amount of MPO in plasma. Recently, estrogen replacement therapy has been reported to reduce the risk of developing AD and to help maintain cognitive function in patients with AD. In the current study, we analyzed the MPO -463 polymorphism and two estrogen receptor-alpha polymorphisms in 205 Japanese sporadic AD patients and 92 controls. The results suggest that there is no significant difference in the genotypic frequencies and allelic frequencies of the MPO -463 polymorphism and the estrogen receptor-alpha polymorphisms between the Japanese sporadic AD group and the control group. [ABSTRACT FROM AUTHOR]

The identification of the epsilon4 variant of apolipoprotein E as a genetic risk factor for late-onset Alzheimer's disease (AD) suggests that cholesterol may play a direct role in the pathogenesis of the disease. Recent studies have suggested that the ATP-binding cassette (ABC) protein G5 (ABCG5) may be involved in the regulation of intestinal cholesterol absorption. Furthermore, genetic variation of this locus may affect blood cholesterol concentrations. We therefore studied whether the ABCG5 C1950G (Gln640Glu) polymorphism affects the risk of AD. In addition, there was no difference in mean baseline cholesterol concentrations between individuals with the C/C genotype and carriers of the G allele. Recent studies have shown that genetic regions including the ABCA12 gene might also be associated with the risk of AD. The ABCA12 gene, located <1 Mb from the peak marker on chromosome 2q34, is also a member of the ABC transporter superfamily. In the current study, two common polymorphisms of the ABCA12 gene, rs952718 (T/G) and rs956133 (A/G), were analyzed in our subjects. These polymorphisms showed no association with the risk of AD. Furthermore, we observed weak linkage disequilibrium between these two single nucleotide polymorphisms. These results indicate that the common polymorphisms of the ABCG5 and ABCA12 genes investigated here are not associated with AD. [ABSTRACT FROM AUTHOR]

Advances of molecular biology have provided a great variety of new approaches to research on human disorders. This article gives an outline of molecular biological approaches to analysis of neurological disorders such as giant cell glioblastoma (GGBM) and amyotrophic lat-eral sclerosis (ALS), and their respective animal models: p53 knockout mice for GGBM and mutant superoxide dismutase-1 transgenic mice for ALS. Genomic DNA extracted from fresh-frozen tissue is examined by Southern blotting for screening mutations in a certain gene. Polymerase chain reaction (PCR) products of a gene in genomic DNA are examined by single-stranded conformation polymorphism, sequencing and agarose gel electrophoresis for identifying mutations, and for preparing and evaluating DNA probes used in Southern blotting and DNA in situ hybridization (ISH). Total RNA from tissue is examined by northern blotting for quantifying and verifying a certain mRNA. Reverse transcription-PCR products of a certain mRNA in total RNA are examined by sequencing and agarose gel electrophoresis for preparing and evaluating cDNA probes used in northern blotting and mRNA ISH. Tissue total protein is immunoblotted for quantifying and verifying a certain protein, and for evaluating the specificity of antibodies used in western blotting and immunohistochemistry. Immunoprecipitates are im-munoblotted for evaluating a profile of protein or other substances. Enzyme-linked immunosorbent assay is used for measuring tissue concentration of protein or other substances, and for determining titers of specific antibodies. By these procedures, chronological analysis of animal models for human diseases contribute to elucidating pathogenic mechanisms and exploiting new therapies. Noticing both the similarity and difference between human and animal disorders will help understand the nature of disease. [ABSTRACT FROM AUTHOR]

Small-angle symmetric [001] tilt grain boundaries in cubic zirconia bicrystals with misorientation angles 2θ =1.0° and 2θ =5.0° have been fabricated by diffusion bonding. High-resolution electron microscopy observations revealed that the 1.0° boundary consists of a periodic array of mixed dislocations with Burgers vector b =(a/2)[101] or b = (a/2)[101], while the 5.0° boundary consists of a periodic array of edge dislocations with Burgers vector b = (a/2)[100], associated with stacking faults at alternate intervals. This suggests that there is a critical angle for structural transitions in the series of the [001] small-angle tilt grain boundaries. [ABSTRACT FROM AUTHOR]

Familial amyotrophic lateral sclerosis (ALS) with mutations in the gene for superoxide dismutase-1 (SOD1) is clinicopathologically reproduced by transgenic mice expressing mutant forms of SOD1 detectable in familial ALS patients. Motor neuron degeneration associated with SOD1 mutation has been thought to result from a novel neurotoxicity of mutant SOD1, but not from a reduction in activity of this enzyme, based on autosomal dominant transmission of SOD1 mutant familial ALS and its transgenic mouse model, clinical severity of the ALS patients independent to enzyme activity, no ALS-like disease in SOD1 knockout or wild-type SOD1-over-expressing mice, and clinicopathological severity of mutant SOD1 transgenic mice dependent on transgene copy numbers. Proposed mechanisms of motor neuron de-generation such as oxidative injury, peroxynitrite toxicity, cytoskeletal disorganization, glutamate excitotoxicity, disrupted calcium homeostasis, SOD1 aggregation, car-bonyl stress and apoptosis have been discussed. Intracy-toplasmic vacuoles, indicative of increased oxidative damage to the mitochondria and endoplasmic reticulum, in the neuropil and motor neurons appear in high expressors of mutant SOD1 transgenic mice but not in low expressors of the mice or familial ALS patients, suggesting that overexpression of mutant SOD1 in mice may enhance oxidative stress generation from this enzyme. Thus, transgenic mice carrying small transgene copy numbers of mutant SOD1 would provide a beneficial animal model for SOD1 mutant familial ALS. Such a model would contribute to elucidating the pathomechanism of this disease and establishing new therapeutic agents. [ABSTRACT FROM AUTHOR]

Two main factors that affect the pharmacokinetics of cyclosporin A (CsA) during 24-h durable intravenous (DIV) administration have been reported, namely physiological changes after bone marrow transplantation, and blood sampling through indwelling lines. In addition, it has been found that infusion sets made of polyvinyl chloride (PVC) markedly adsorb CsA. We conducted in vitro adsorption studies of CsA on infusion sets, and the administration routes that are used in the treatment of patients with bone marrow transplantation. We also examined the effects of administration route on CsA pharmacokinetics in clinical practice. The in vitro adsorption study using 30-mm segments of lumen from commercially available infusion sets showed that the degree of CsA adsorption per area of lumen made of PVC was significantly higher than that in those made of polyethylene (PE) or polybutadiene (PB), which showed no adsorption of CsA. Due to its adsorption, use of infusion sets made of PVC resulted in about a 40–50% loss of CsA dose, which affected the pharmacokinetic parameters during 24-h DIV, while those made of PE and PB did not. The use of non-PVC infusion sets should allow for accurate monitoring of CsA results, and provide cost benefit in the treatment of bone marrow transplantation. Bone Marrow Transplantation (2000) 25, 633–638. [ABSTRACT FROM AUTHOR]

The expression of tumour necrosis factor-alpha (TNF-α) gene in peripheral blood mononuclear cells from patients with systemic vasculitis, periarteritis nodosa and Wegener's granulomatosis, has been studied by RNA dot blot and Northern blot assays. We further examined the transcriptional level of TNF-α gene in peripheral blood mononuclear cells from these patients by performing nuclear run on transcription assay. We demonstrate enhanced TNF-x gene expression in mononuclear cells from these patients compared with healthy subjects and patients with bronchial asthma. These findings suggest that the enhanced transcription of TNF-a gene in peripheral blood mononuclear cells from patients with systemic vasculitis may be involved in the pathophysiology/pathogenesis of these diseases by cytokine dysregulation. [ABSTRACT FROM AUTHOR]

Scleroderma is a systemic disorder characterized by fibrosis, which affects skin, lung, kidney and other organs. Heat shock protein (hsp) (70 kD) has been implicated as an essential element of cell function in cell growth and differentiation. To study the molecular basis of intracellular events in scleroderma fibroblasts. we compared the expression of bsp 70 gene in scleroderma and normal control fibroblasts by nuclear run on transcription assay and Northern biot assay. We show that scleroderma fibroblasts express more than eight times higher level of bsp 70 transcription in normal control fibroblasts at quiescent conditions in the absence of serum. After stimulation with serum, the transcription level of the bsp 70 gene is similar in scleroderma and normal control fibroblasts. Therefore, our results indicate an alteration/activation of intracellular events in scleroderma fibroblasts. [ABSTRACT FROM AUTHOR]

Analyzes the local stability of field-reversed configurations (FRC) using hydrodynamic stability theory. Inclusion of compressibility and double-adiabatic effects; Eigenmodes of the linearized equations of motion; Appearance of fast local modes that raise the possibility of regulation of FRC equilibria.

We show that an annular detector placed within the bright field cone in scanning transmission electron microscopy allows direct imaging of light elements in crystals. In contrast to common high angle annular dark field imaging, both light and heavy atom columns are visible simultaneously. In contrast to common bright field imaging, the images are directly and robustly interpretable over a large range of thicknesses. We demonstrate this through systematic simulations and present a simple physical model to obtain some insight into the scattering dynamics. [ABSTRACT FROM AUTHOR]

Abstract: An effect of hypergravity created by strong downward magnetic force on orientation of a nanometer-sized substance suspended in water, which is likely to be prevented because of ambient thermal energy, was studied by using cylindrical aggregates (nanorods) made of tetrakis(4-sulfonatophenyl)porphine (TPPS). Some of the rods were arranged in a direction parallel to a vertical magnetic field of 12T under the hypergravity while no magnetic orientation took place even at a stronger magnetic field of 15T where the usual gravity existed. This phenomenon was not explained by the diamagnetic susceptibility anisotropy of the rod. At present it was interpreted as an orientation accomplished hydrodynamically in a process of the rod precipitation accelerated by the downward magnetic force under the hypergravity. [Copyright &y& Elsevier]

Discusses the performance of low-energy oxygen ion implantation on a pseudomorphic silicon germanium alloy grown Si(001) of uniform composition in an attempt to create a SiGe-on-insulator substrate using the separation-by-implanted-oxygen technique. Importance of choosing a small Ge composition in achieving a SiGe-OI geometry of structural integrity.

A Si substrate purposely grown for Si-based optoelectronic applications is described in this letter. The structure contains a built-in Si/SiO2 Bragg reflector which is prepared by multiple separation-by-implanted-oxygen technique, where in situ low energy oxygen ion implantation is performed on molecular beam deposited Si to create alternating Si/SiO2 epitaxial bilayers. The quality of the top Si layer was confirmed to be epitaxy-ready after cross-sectional transmission electron microscopy. Maximum reflectance at near normal incidence was over 90% for bilayer periods of 4 to 5. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a technique for fabricating highly oriented silicon (Si) nanoparticles (SNP) embedded in Si dioxide. Use of multiple low energy oxygen ion implantation during Si molecular beam epitaxy; Description of the nanoparticles; Observation of visible luminescence from SNP with dimensions approaching the quantum confinement regime.

Discusses the computation of the local eigenmodes of field-reversed configurations using ideal magnetohydrodynamics. Comparison of the eigenmodes with earlier analytic models; Similarity of the analytic models to actual eigenmodes in structure and growth rate; Failure of the analytic models to predict features of the eigenmode behavior.

The use of the high-temperature-annealed self-buffer layer (HITAB) enabled to observe free A-and B-exciton emissions at 9 K from ZnO heteroepitaxial films grown by the sputtering epitaxy method using a helicon-wave-excited plasma on uniaxially nearly lattice-matched (1120) Al2O3 substrates. The result was correlated with a twofold decrease in the densities of threading dislocations having both the screw and edge components, according to the dislocation concealing in ZnO HITAB due to lateral mass transport of low-temperature deposited ZnO nanocrystalline grains during high temperature annealing. [ABSTRACT FROM AUTHOR]

Highlights • The selective recovery of indium was achieved in CCFS from sulfuric acid solution. • Anionic organophosphate surfactant was selected as the selective metal collector. • The screening tests on anionic/nonionic surfactants on the market were carried out. Abstract Continuous counter-current foam separation (CCFS) with simultaneous injections of metal and surfactant solutions respectively into rising foam bed was applied to In(III) recovery from sulfuric acid solutions containing ternary metal ions of In/Cu/Zn. Through the screening tests of the surfactants in both conventional batch foam separation and CCFS, anionic organophosphate surfactant which has similar structure to phosphoric acid extractant (D2EHPA) was selected as the metal collector, with an addition of a nonionic co-surfactant as the foam stabilizer. The optimized surfactant combination was shown anionic A219B/nonionic POOE20 in this study; the complete recovery of In(III) was attained with the enrichment ratio of 5.5, whereas those of the other metals were suppressed in trace level, resulting in the excellent selective recovery. Moreover, metal solutions of quaternary In/Fe/Cu/Zn were also examined, and a dose of reductant for interfering Fe(III) into the metal solution was executed for improving the separation efficiency; the dose of ascorbic acid could invert the affinity order of A219B from Fe > In to In > Fe. The percent recovery and enrichment ratio of In(III) were 97% and 5.5, while the separation factors of In/Fe, In/Cu and In/Zn were 93, 1300 and 1300 respectively. This is our first favorable case for expanding the choice range of target metal ions in CCFS using anionic surfactants. [ABSTRACT FROM AUTHOR]

Proposes an annealing method as an effective way of operating quantum-cellular-automation (QCA) systems. Utilization of the minimum energy state of electrons in a quantum cell system; Applicability of QCA systems to non-Neumann parallel-processing computation; Dealing with two fundamental problems in developing QCAs into practical devices.

It is shown that Notch 4 plays important roles in the pathogenesis of Alzheimer's disease (AD). To investigate whether three single nucleotide polymorphisms (SNPs) of the Notch4 gene are associated with AD, the three SNPs were genotyped by a polymerase chain reaction-restriction fragment length polymorphism method for 243 AD patients and 130 age-matched controls. We also confirmed the linkage disequilibrium among these three SNPs of the gene using the EH program. The three SNPs did not seem to alter risk for AD. Our study suggests that SNPs studied are not associated with AD. The linkage disequilibrium of this locus indicates that there is genetic heterogeneity in the Notch4 gene. We could not confirm the previous synergetic associations of the 5' untranslated region (rs367398) C/C genotype in apolipoprotein E epsilon4 bearers in AD patients. Potential markers nearby the 5' untranslated region polymorphism might affect risk for AD. [ABSTRACT FROM AUTHOR]

Abstract: The Fano–Kondo effect in zero-bias conductance is studied based on a theoretical model for the T-shaped quantum dot by the finite temperature density matrix renormalization group method. The modification of the two Fano line shapes at much higher temperatures than the Kondo temperature is also investigated by the effective Fano parameter estimated as a fitting parameter. [Copyright &y& Elsevier]

Objective Sjögren's syndrome ( SS) is a systemic autoimmune disease that primarily affects lacrimal and salivary glands. We previously reported that FliC derived from Escherichia coli could induce autoimmune pancreatitis-like lesions. From these results, we speculated that FliC could also induce SS-like exocrinopathy. In this study, we investigated the effects of chronic exposure to FliC on lacrimal and salivary glands and the possibility that it might lead to an autoimmune response. Methods C57 BL/6 mice were repeatedly injected with FliC and histological changes, serum levels of cytokine/chemokines and autoantibodies were evaluated at different time points after the final injection. The presence of sialadenitis was diagnosed by histological methods. Results In FliC-treated groups, 57% of subjects developed inflammatory cell infiltrates around ducts in mandibular salivary glands, but not lacrimal glands. In addition, serum levels of total IgG, IgG1, and IgG2a were significantly higher in FliC-treated groups. Intriguingly, serum anti- SSA/Ro levels were also significantly higher in FliC-treated groups. Cytokine analysis revealed that serum levels of IL-1 β, IL-12p70, IL-13, IFN- γ, IL-15, and IL-23 seemed to be higher in FliC-treated mice. Conclusions Our data suggest that FliC-treated mice develop an SS-like phenotype. Our model may elucidate the relationship between commensal bacteria and SS. [ABSTRACT FROM AUTHOR]

Differential phase contrast images in scanning transmission electron microscopy can be directly and quantitatively related to the gradient of the projected specimen potential provided that (a) the specimen can be treated as a phase object and (b) full 2D diffraction patterns as a function of probe position can be obtained. Both are challenging to achieve in atomic resolution imaging. The former is fundamentally limited by probe spreading and dynamical electron scattering, and we explore its validity domain in the context of atomic resolution differential phase contrast imaging. The latter, for which proof-of-principle experimental data sets exist, is not yet routine. We explore the extent to which more established segmented detector geometries can instead be used to reconstruct a quantitatively good approximation to the projected specimen potential. [ABSTRACT FROM AUTHOR]

Si quantum wires (QWRs) suspended in SiO[sub 2] are successfully created on a V-groove patterned Si(001) substrate by using low-energy oxygen ion implantation. A single Si QWR aligned to [110] is formed near the bottom center of the V groove, which has a hexagonal cross section with {111} and {001} lateral facets. The development of Si QWRs was found to be controlled by the oxygen ion dose and the formation mechanism is attributed to an oxygen ion enrichment near the V-groove corner which arises from lateral ion straggling. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Chemical mapping using energy dispersive X-ray spectroscopy (EDS) in scanning transmission electron microscopy (STEM) has recently shown to be a powerful technique in analyzing the elemental identity and location of atomic columns in materials at atomic resolution. However, most applications of EDS STEM have been used only to qualitatively map whether elements are present at specific sites. Obtaining calibrated EDS STEM maps so that they are on an absolute scale is a difficult task and even if one achieves this, extracting quantitative information about the specimen – such as the number or density of atoms under the probe – adds yet another layer of complexity to the analysis due to the multiple elastic and inelastic scattering of the electron probe. Quantitative information may be obtained by comparing calibrated EDS STEM with theoretical simulations, but in this case a model of the structure must be assumed a priori . Here we first theoretically explore how exactly elastic and thermal scattering of the probe confounds the quantitative information one is able to extract about the specimen from an EDS STEM map. We then show using simulation how tilting the specimen (or incident probe) can reduce the effects of scattering and how it can provide quantitative information about the specimen. We then discuss drawbacks of this method – such as the loss of atomic resolution along the tilt direction – but follow this with a possible remedy: precession averaged EDS STEM mapping. [ABSTRACT FROM AUTHOR]