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The objective of this research is to demonstrate the capability of a long stroke linear ferrofluid (FF) stage. This stage is a passive alternative to existing linear aerostatic stages and can be used in low loaded CNC devices, pick and place machines, microscopy or scanner applications. To compete with aerostatic stages the bearing must be repeatable and achieve sufficient stiffness for the application. The effects of ferrofluid trail formation are countered with the use of a ferrofluid reservoir located on the mover. To increase stiffness a specially designed magnet configuration is used. A linear guidance was built with outer dimensions of 180x600x80 mm (WxLxH), a mover of 1.8 kg without actuator and payload having a 430 mm stroke. The load capacity of the stage was measured to be 120 N, with a stiffness of 0.4 N/ μ m. The maximum height delta after a stroke with 1 kg payload and a mover velocity of 0.25 m/s was measured to be less than ± 3 μ m , and with 1.75 kg payload and a velocity of 0.5 m/s the height delta was within ± 7 μ m. Using a rheometer, it was shown that the effects of evaporation in ferrofluid can be reversed, within certain limits of mass loss, by adding carrier fluid. The damping is shown to be a function of payload and velocity and was measured to be between 2 and 4 N ⋅ s/m for velocities between 0.2 and 0.5 m/s. In comparison to a linear aerostatic stage it can be concluded that while the linear ferrofluid stage is outperformed in stiffness and out-of-plane repeatability, the ferrofluid stage does not require a continuous supply of air and has lower fabrication tolerances due to the higher fly height. Thus, the linear ferrofluid stage is a cost-effective alternative to a linear aerostatic stage when the stiffness and straightness are of less importance. • The ferrofluid bearing stage works passively and has low manufacturing tolerances. • Using pressure bearing pads, a long stroke ferrofluid bearing can be created. • The effects of ferrofluid evaporation on the bearing can be prevented and reversed. • Eddy current damping in ferrofluid bearings can be reduced by using slender magnets. • The ferrofluid stage is a cost-effective alternative bearings in precise positioning. [ABSTRACT FROM AUTHOR]

In South Africa the challenges facing the post-school vocational education system are daunting. There is a lack of coherence, resulting in fragmentation of the system. A Training Needs Assessment Study commissioned in 2014 revealed several major academic challenges facing college leadership. The most pressing issues were poor leadership and management skills and challenges facing lecturers in various aspects of teaching and learning, amongst which were blatant shortcomings in their capabilities to meet the competencies required for effective lecturing. This realisation led the researchers to hypothesise that ineffective and fragmented leadership and management practices may be to blame for this state of affairs. The researchers wondered whether an integrated and focused leadership model aimed at distributing ownership for student achievement should be implemented to produce better results. The overarching research question was: What are the main stumbling blocks in improving National Certificate: Vocational (NC(V)) students’ performance at technical and vocational education and training (TVET) colleges; and how can a distributed instructional leadership approach be conceptualised to address the problems at institutional level? A qualitative research approach was used, which was mainly inductive, providing a clear understanding of the participants’ views and capturing their perceptions in their own words. A phenomenological design was used as strategy of inquiry. The findings created an awareness for considering collaboration and the distribution of powers and capabilities to bring about a shared leadership vision in the quest for challenging poor performance at institutional level in a sector that is in dire need of positive outcomes. [ABSTRACT FROM AUTHOR]

We studied the predictive performance of the Minto pharmacokinetic model during cardiopulmonary bypass in patients undergoing cardiac surgery. Patients received remifentanil target-controlled infusion using the Minto model during total intravenous anaesthesia with propofol. From 56 patients, 275 arterial blood samples were drawn before, during and after bypass to determine the plasma concentration of remifentanil, and the predicted concentrations were recorded at each time. For pooled data, the median prediction error and median absolute prediction error were 21.3% and 21.8%, respectively, and 22.1% and 22.3% during bypass. Both were 148.4% during hypothermic circulatory arrest and measured concentrations were more than three times greater than predicted (26.9 (17.0) vs. 7.1 (1.6) ng.ml-1 ). The Minto model showed considerable bias but overall acceptable precision during bypass. The target concentration of remifentanil should be reduced when using the Minto model during hypothermic circulatory arrest. [ABSTRACT FROM AUTHOR]

The extended active shape models have shown their robustness in facial landmarks fitting. However, we often meet substantial errors of lip landmarks fitting mostly due to teeth boundaries. An attempt to reduce the errors using high-quality mouth maps has been made recently. Since most existing facial datasets cannot produce high-quality mouth maps, use of mouth maps should be careful not to bring even more serious errors from them. Unlike the existing scheme using the mouth map, we use the mouth map not for profile model but only for better initialisation of landmarks right before profile matching. As a result, the proposed method attains higher accuracies compared to the original Stasm 4 and the existing method using the mouth map. Experimental studies validate the effectiveness of the proposed method. Since the proposed method uses the mouth map only for initialisation, it requires neither additional task in training nor high-quality mouth maps. [ABSTRACT FROM PUBLISHER]

Efinaconazole is a new triazole antifungal for topical treatment of onychomycosis. The reproductive and developmental toxicity of efinaconazole was characterized in fertility and early embryonic development (rat), embryo-fetal development (rat and rabbit), and peri/post-natal development (rat) studies in accordance with current ICH guidances. In the fertility study, maternal reproductive toxicity was noted as estrous cycle prolongation (NOAEL = 5 mg/kg/day) but there were no male reproductive effects even in the presence of paternal toxicity (NOAEL = 25 mg/kg/day). Rat embryo-fetal and perinatal pup lethality was the most sensitive (NOAEL = 5 mg/kg/day) efinaconazole developmental toxicity and was noted at maternally toxic doses. Efinaconazole did not affect rabbit embryo-fetal development at maternally toxic doses (NOAEL = 10 mg/kg/day). No malformations were induced by efinaconazole in rats or rabbits. When compared with systemic exposures observed in onychomycosis patients, embryo-fetal toxicity in rats was noted at high (>100-fold) multiples of systemic exposure. [ABSTRACT FROM AUTHOR]

We observed the surface morphology and adhesive interaction of adsorbents on rubber substrates by atomic force microscopy (AFM). The detachment of adsorbents from rubber substrates is an important issue for various machines like home appliances and laundry machine. Since a clean surface of the functioning parts is required, a frequent cleaning process must be developed. In particular, dust and lint have a tendency to bind to the rubber surface of a laundry machine. Several practical methods have been attempted to remove these particles from the surface. Pure water, detergent, sodium hypochlorite (65 °C), and cold water (18 °C) are treated onto artificial dust and lint mixtures on rubber with water fluid by rapid rpm. The dust-and-lint adsorbents are investigated by AFM after the treatment, and topographic images and force-distance ( F-D) curves were generated for the samples. The roughness, measured as the root mean square, is a key factor to judge the cleaning quality. From the F-D curves, we are able to obtain adhesive energy in addition to adhesive force which will yield qualitative measures of the interactions between the remaining adsorbents and the rubber surface. Considering the values that were measured, hot water with water fluid by rapid rpm offers the best performance when cleaning the surface. The chemical like sodium hypochlorite is good for thinning the materials, but it solidifies them, which is eventually detrimental to proper functioning. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) and vascular dementia are the major causes of cognitive disorders worldwide. They are characterized by cognitive impairments along with neuropsychiatric symptoms, and that their pathogeneses show overlapping multifactorial mechanisms. Although AD has long been considered the most common cause of dementia, individuals afflicted with AD commonly exhibit cerebral vascular abnormalities. The concept of mixed dementia has emerged to more clearly identify patients with neurodegenerative phenomena exhibiting both AD and cerebral vascular pathologies-vascular damage along with β-amyloid (Aβ)-associated neurotoxicity and τ-hyperphosphorylation. Cognitive impairment has long been commonly explained through a 'neuro-centric' perspective, but emerging evidence has shed light over the important roles that neurovascular unit dysfunction could have in neuronal death. Moreover, accumulating data have been demonstrating astrocytes being the essential cell type in maintaining proper central nervous system functioning. In relation to dementia, the roles of astrocytes in Aβ deposition and clearance are unclear. This article emphasizes the multiple events triggered by ischemia and the cytotoxicity exerted by Aβ either alone or in association with endothelin-1 and receptor for advanced glycation end products, thereby leading to neurodegeneration in an 'astroglio-centric' perspective. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the structural and optical properties of Cu-poor CuGaSe2 (CGSe) films depending on the use of different substrates: indium-doped tin oxide (ITO) coated soda-lime glass (SLG) and fluorine-doped tin oxide (FTO) coated SLG as back contacts, widely used Mo-coated SLG, and pure SLG. The Cu-poor phase is chosen as a counterpart of Cu-poor Cu(In,Ga)Se2 to show the highest efficiency in this class of materials, and also give a test board for parasitic phases which might influence on device properties. Although the Cu-poor CGSe thin-films were deposited on the four substrates at the same time in an identical condition, they showed differences in the morphology and grain size due to different CGSe/substrate interfaces and growth mechanisms depending on the substrates. These surface properties of the CGSe films were identified clearly by atomic force microscopy (AFM) measurements. X-ray diffraction (XRD) measurement also supported the result of the AFM analysis and showed that the preferred orientation of CGSe is (112), independent of the substrates. The existence of parasitic phases was examined by Raman and photoluminescence spectroscopic techniques. While defect compounds such as CuGa3Se5 and CuGa5Se8 were identified for all films, the signals related to these parasitic phases are strongest for the films on the pure SLG substrate. Furthermore, the absorption property was investigated by spectroscopic ellipsometry in a photon energy range of 0.7–5 eV. We found that the absorption coefficient values for the CGSe films are about 104–105 cm−1 in the visible region. The absorption coefficient is also changed according to the use of different substrates. This difference comes from the parasitic phase formation, which leads to an increase of the bandgap and suppression of the optical absorption strength. Our systematic study suggests clearly that the difference in distribution of parasitic phases in the CGSe films could originate primarily from the different substrates used for the film deposition. [Copyright &y& Elsevier]

Abstract: A novel thermal micro-stepper motor (TMM) principle based on friction and thermal expansion has been developed. Its objective is to move, rotate, align and adjust micro-objects with nanometre precision while having a long stroke. In this study, the design of a linear and a rotational motor and their microfabrication is presented. The fabricated devices were characterised and the first experimental results are presented. Several challenges in MEMS design, microfabrication and micro-assemble the future moving axel with the microsystem had to be overcome. [Copyright &y& Elsevier]

Abstract: Structural properties of Cu(In,Ga)Se2 absorber layers have been examined for photovoltaic applications. Thin-films with three different chemical compositions, CuInSe2 (CIS), Cu(In,Ga)Se2 (CIGS) and CuGaSe2 (CGS), were grown by co-evaporation on two kinds of substrates: Mo-coated soda-lime glass and bare soda-lime glass. Intriguing morphology and grain-growth behaviors were found in the surface of the films. X-ray diffraction of the films exhibited phase formation of the stoichiometric chalcopyrite phase of the materials while signs of secondary phases like Cu2Se and Cu–Se2 were also observed. The optical transmittance of the films was measured to obtain their optical bandgaps, which were well matched with the bulk values of CIS, CIGS, and CGS, which are 1.1, 1.4, and 1.7 eV, respectively. Using Raman scattering spectroscopy, the A1 mode was observed to shift from 177 cm−1 for CIS to 189 cm−1 for CGS as the Ga content increased. The films on Mo substrates are likely to have secondary phases, which is not the case for soda-lime glass. An indication of the formation of the CuAu structure is obtained from the CIS thin-films. [Copyright &y& Elsevier]

Electrical transport properties on polycrystalline Cu(In,Ga)Se (CIGS) (Ga/(In+Ga) ≈35%) thin films were examined by conductive atomic force microscopy. The CIGS thin films with a (112) preferential or random texture were deposited on Mo-coated glass substrates. Triangular pyramidal grain growths were observed in the CIGS thin films preferentially textured to the (112) planes. Current maps of the CIGS surface were acquired with a zero or non-zero external voltage bias. The contrast of the images on the grain boundaries and intragrains displayed the conduction path in the materials. Local current-voltage measurements were performed to evaluate the charge conduction properties of the CIGS thin films. [ABSTRACT FROM AUTHOR]

Abstract: Nanoparticles of CuInSe2 (CIS) were synthesized by pulsed laser ablation. The effect of the preparation conditions on the structural properties of the CIS nanoparticles was investigated. The CIS nanoparticles showed a more developed structural property after treatment in Se-evaporated atmosphere. By X-ray photoelectron spectroscopy, increase of Se amounts in the CIS nanoparticles was confirmed. Enhancement of phonon modes in the CIS nanoparticles was observed in Raman scattering spectroscopy while secondary phases like In2Se3 or CuAu structure-related peak were identified in the spectra. High-resolution transmission electron microscopy indicated that the individual nanoparticles were embedded in matrix of some amorphous layers and diffraction patterns representing the chalcopyrite structure were also scrutinized. [Copyright &y& Elsevier]

SmBa2Cu3O7 (SmBCO)-coated conductors were grown on IBAD-MgO templates by in-situ co-evaporation using a drum-in-dual-chambers system. The conductors, which had a coating thickness of up to 3 \mum, showed a critical temperature of 92 \sim 94 K and a critical current of 150 \sim 625 A/cm-w at 77 K in a self-field. The phonon modes and cation disorder of the SmBCO-coated conductors were examined by polarized Raman scattering spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy. XRD showed (00l) peaks for the SmBCO phase. The Raman spectra revealed common vibration modes, including Ba-Ba stretching, Cu2-Cu2 stretching, O(2)+/O(3)-, and apical O(4) modes. In addition, polarized-Raman spectra were obtained to examine the crystal orientation and grain growth behavior. Structural information from the Raman spectra turned out to be useful to determine the optimal thickness of SmBCO-coated conductors with high critical currents. [ABSTRACT FROM AUTHOR]

SmBa2Cu3O7 (SmBCO) coated conductors were grown on IBAD-MgO templates the evaporation using a drum-in-dual-chambers (EDDC) deposition system. The material showed a critical temperature of 93 \sim 94 K and a critical current of 200 \sim 250 A/cm-width at 77 K in a self-field. The current-limiting properties and local structure of the films were examined by laser-induced thermoelectric (LITE) imaging and low temperature laser scanning microscopy (LTLSM). Surface morphology and chemical composition of the superconducting layers were examined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), respectively. A 100\ \mum\times 1\ mm-microbridge was fabricated using a photolithographic technique and etching process. The measured LITE images of the SmBCO coated conductor showed that some grains on the surface, surface inhomogeneity, second phases, defects and tilted grains, cause different thermal gradients. The LTLSM images revealed two dimensional variations of local flux flow on the films as a function of the local critical current. The findings are consistent with the LITE images, indicating that both methods can visualize the local structures and phases. [ABSTRACT FROM AUTHOR]

Abstract: We report fabrication of Ti metal nanodot arrays by scanning probe microscopic indentation. A thin poly-methylmethacrylate (PMMA) layer was spin-coated on Si substrates with thickness of 70nm. Nanometer-size pore arrays were formed by indenting the PMMA layer using a cantilever of a scanning probe microscope. Protuberances with irregular boundaries appeared during the indentation process. Control of approach and pulling-out speed during indentation was able to dispose of the protrusions. Ti metal films were deposited on the patterned PMMA layers by a radio-frequency sputtering method and subsequently lifted off to obtain metal nanodot arrays. The fabricated metal nanodot arrays have 200nm of diameter and 500nm of interdistance, which corresponds to a density of 4×108/cm2. Scanning probe-based measurement of current–voltage (I–V) behaviors for a single Ti metal nanodot showed asymmetric characteristics. Applying external bias is likely to induce oxidation of Ti metal, since the conductance decreased and volume change of the dots was observed. I–V behaviors of Ti metal nanodots by conventional e-beam lithography were also characterized for comparison. [Copyright &y& Elsevier]

Abstract: In this study, we characterized the two-dimensional lattice of bovine serum albumin (BSA) as a chemical and physical barrier against bacterial adhesion, using fluorescence microscopy and atomic force microscopy (AFM). The lattice of BSA on glass surface was fabricated by micro-contact printing (μCP), which is a useful way to pattern a wide range of molecules into microscale features on different types of substrates. The contact-mode AFM measurements showed that the average height of the printed BSA monolayer was 5–6nm. Escherichia coli adhered rapidly on bare glass slide, while the bacterial adhesion was minimized on the lattices in the range of 1–3μm2. Especially, the bacterial adhesion was completely inhibited on a 1μm2 lattice. The results suggest that the anti-adhesion effects are due by the steric repulsion forces exerted by BSA. [Copyright &y& Elsevier]

Abstract: SrRuO3 thin films have been grown in situ on single crystal LaAlO3 substrates and textured metal templates which contain an MgO layer produced by an ion-beam growth method. Deposition was made of oxygen partial pressure in a range from 50mTorr to 250mTorr with laser repetition rate of 5Hz. Substrate temperature was between 600°C and 800°C. Dependence of out-of-plane and in-plane orientation of SrRuO3 thin films on pressure and growth temperature was investigated by X-ray diffraction. The surface morphology and grain growth behaviors of SrRuO3 thin films were analyzed by atomic force microscopy and scanning electron microscopy. In addition, the transverse magnetoresistance value in a field of 4 and 8T was measured in temperature range of 50–200K and the ferromagnetic transition at ∼140K of SrRuO3 films on LaAlO3 was detected by resistivity measurement. [Copyright &y& Elsevier]

Abstract: Biofilms are complex microbial communities that are resistant against attacks by bacteriophages and removal by drugs and chemicals. In this study, biofilms of Escherichia coli O157:H7, a bacterial pathogen, were investigated using atomic force microscopy (AFM) in terms of the dynamic transition of morphology and surface properties of bacterial cells over the development of biofilms. The physical and topographical properties of biofilms are different, depending on nutrient availability. Compared to biofilms formed in a high nutrient medium, biofilms form faster and a higher number of bacterial cells were recovered on glass surface in a low nutrient medium. We demonstrate that AFM can obtain high-resolution images and the elastic information about biofilms. As E. coli biofilm becomes mature, the magnitude of the force between a tip and the surface of the biofilm gets stronger, suggesting that extracellular polymeric substances (EPSs), sticky components of biofilms, accumulate over the surface of cells upon the initial attachment of bacterial cells to surfaces. [Copyright &y& Elsevier]

Abstract: Phase-change Ge–Sb–Te (GST) nanoparticles have been in-situ synthesized by a pulsed-laser ablation method. During the ablation process, growth parameters including temperature of heat treatment, pressure, and laser fluence are extensively explored. Scanning and transmission electron microscopy are used to study microstructure and phase formation of the nanoparticles. Fourier transform analysis of electron micrographs exhibits an evidence of existence of the stoichiometric single GST-225 phase. We have measured micro-Raman scattering spectra of commercially available GST-124, -147, and -225 bulk and GST nanoparticles. Lack of the amorphous Te–Te stretching mode near 150cm−1 from the Raman spectra of the bulk samples indicates that the samples are well-crystallized. From the measurements of GST nanoparticles with different growth conditions, we could get information towards the optimal growth conditions for better crystalline quality of the GST nanoparticles. Our results suggest that micro-Raman scattering spectroscopy can be used to study phases and phase changes in the GST bulk crystals and nanoparticles through local structural information, which is being developed for low-power non-volatile memory applications. [Copyright &y& Elsevier]

Question: How do studies of the distribution of genetic diversity of species with different life forms contribute to the development of conservation strategies? Location: Old-growth forests of the southeastern United States. Methods: Reviews of the plant allozyme literature are used to identify differences in genetic diversity and structure among species with different life forms, distributions and breeding systems. The general results are illustrated by case studies of four plant species characteristic of two widespread old-growth forest communities of the southeastern United States: the Pinus palustris -- Aristida stricta (Longleaf pine -- wiregrass) savanna of the Coastal Plain and the Quercus -- Carya -- Pinus (Oak-hickory-pine) forest of the Piedmont. Genetic variation patterns of single-gene and quantitative traits are also reviewed. Results: Dominant forest trees, represented by Pinus palustris (longleaf pine) and Quercus rubra (Northern red oak), maintain most of their genetic diversity within their populations whereas a higher proportion of the genetic diversity of herbaceous understorey species such as Sarracenia leucophylla and Trillium reliquum is distributed among their populations. The herbaceous species also tend to have more population-to-population variation in genetic diversity. Higher genetic differentiation among populations is seen for quantitative traits than for allozyme traits, indicating that interpopulation variation in quantitative traits is influenced by natural selection. Conclusion: Developing effective conservation strategies for one or a few species may not prove adequate for species with other combinations of traits. Given suitable empirical studies, it should be possible to design efficient conservation programs that maintain natural levels of genetic diversity within species of conservation interest. [ABSTRACT FROM AUTHOR]

Abstract: Optical response and topography of fluorescent latex beads both on flat self-assembled monolayer and on a micron-patterned surface with poly(dimethylsiloxane) are studied. Scanning near-field optical microscopy and atomic force microscopy were utilized together for detecting fluorescence and imaging topography of the patterned latex beads, respectively. As a result, the micro-patterned latex beads where a specific chemical binding occurred show a strong signal, whereas no signals are observed in the case of nonspecific binding. With fluorescein isothiocyanate (FITC), it is convenient to measure fluorescence signal from the patterned beads allowing us to monitor the small balls of fluorescent latex. [Copyright &y& Elsevier]

Question: How do studies of the distribution of genetic diversity of species with different life forms contribute to the development of conservation strategies? Location: Old‐growth forests of the southeastern United States. Methods: Reviews of the plant allozyme literature are used to identify differences in genetic diversity and structure among species with different life forms, distributions and breeding systems. The general results are illustrated by case studies of four plant species characteristic of two widespread old‐growth forest communities of the southeastern United States: the Pinus palustris – Aristida stricta (Longleaf pine – wiregrass) savanna of the Coastal Plain and the Quercus – Carya – Pinus (Oak‐hickory‐pine) forest of the Piedmont. Genetic variation patterns of single‐gene and quantitative traits are also reviewed. Results: Dominant forest trees, represented by Pinus palustris(longleaf pine) and Quercus rubra (Northern red oak), maintain most of their genetic diversity within their populations whereas a higher proportion of the genetic diversity of herbaceous understorey species such as Sarracenia leucophylla and Trillium reliquum is distributed among their populations. The herbaceous species also tend to have more population‐to‐population variation in genetic diversity. Higher genetic differentiation among populations is seen for quantitative traits than for allozyme traits, indicating that interpopulation variation in quantitative traits is influenced by natural selection. Conclusion: Developing effective conservation strategies for one or a few species may not prove adequate for species with other combinations of traits. Given suitable empirical studies, it should be possible to design efficient conservation programs that maintain natural levels of genetic diversity within species of conservation interest. [ABSTRACT FROM AUTHOR]

Abstract: Highly (001)-oriented ferroelectric PbZr0.53Ti0.47O3 nanolayers are prepared by a sol–gel method on conducting LaNiO3 electrodes with SiO2/Si(100). Ferroelectric domains in the layers are observed using atomic force microscopy, registering the electrostatic force response of the layers in the presence of a low AC field. Surface morphology and domains in the layers are observed using atomic force microscopy with the lock-in amplification technique. We observe a direct correlation between domain configurations and microstructural features in the as-grown nanolayers. Protruded grains show upward polarization, while most of the flat grains display downward polarization, suggesting that overall output of the as-grown polarization might be biased. Switching behavior of the layers reveals a significant asymmetric pattern, which is dependent on the voltage polarity and the original domain structure of the individual grains. This observation is attributed to preference of polarization states of each grain, indicating that local switching behavior is macroscopically expressed as an imprint phenomena. [Copyright &y& Elsevier]

Abstract: Phase-change Ge–Sb–Te (GST) nanoparticles have been in situ synthesized by a pulsed laser ablation method. Temperature of heat treatment, pressure during ablation, and laser fluence are extensively explored to examine growth behavior of GST nanoparticles. Scanning and transmission electron microscopy are used to study microstructure and phase formation of the nanoparticles. Energy dispersive X-ray analysis is performed to look into chemical composition of the GST nanoparticles. It is found that stoichiometric GST nanocrystals with 5–50nm of grain size are formed around 200°C. [Copyright &y& Elsevier]

Advances in medicine and technology have increased brachial artery utilization for diagnostic and interventional radiology. Hence, detection and assessment of variations in upper extremity vasculature are important regardless of the low surgical intervention rate in the upper extremity. Anomalies of the upper extremity artery are infrequently reported, and anomalies of the brachial artery are even less common. Presented here is a case of developmental failure of the brachial artery. A segment about 2.1 cm from its origin was treated with bypass surgery. This is presented as an uncommon variation of the brachial artery. [ABSTRACT FROM AUTHOR]

We report depth profiling of the critical current density and resistivity of YBa2Cu3O7-x films grown by in situ electron beam evaporation. The method is capable of providing important information on the uniformity of the films, and on the commonly observed property that the critical currents in high temperature superconductor coated conductors do not scale linearly with thickness. Local critical current density shows a clear correlation with local resistivity. Homogeneous transport properties with a large critical current density (4–5 MA/cm2 at 77 K, 0 T) are observed in top faulted region while it is found that the bottom part carries little supercurrent with a large local resistivity. Therefore, it is possible that thickness dependence of critical current density is closely related with a topological variation of good superconducting paths and/or grains in the thin film bodies. The information derived from it may be useful in the characterization and optimization of superconducting thin films for electrical power and other applications. [Copyright &y& Elsevier]

We report transport properties of superconducting MgB[sub 2] thin films in-situ grown by molecular beam epitaxy. The MgB[sub 2] films show a superconducting transition at 34.5 K with ΔT[sub c] < 1 K. We measure the in-plane electrical resistivity of the films in magnetic field to 8 T and estimate the upper critical field H[sup ⊥, sub c2](0) ∼ 32 T for field oriented along the c-axis and H[sup , sub c2] (0) ∼ 35 T in the plane of the film. We find the zero-temperature coherence lengths ξ[sub c](0) ∼ 31 Å and ξ[sub ab](0) ∼ 36 Å, indicating the field anisotropy ratio is 1.2, comparable with reported in-situ epitaxial thin films, but less than single crystals. The calculated electronic mean free path l = 25 Å is smaller than the coherence length, which places our films in the dirty limit. Estimates of the critical current density, J[sub c], using magnetic field hysteresis loops and the Bean critical state model give nominal critical current densities on the order of 10[sup 6] A/cm² at 15 K and self-field. [ABSTRACT FROM AUTHOR]

YBa[sub 2]Cu[sub 3]O[sub 7-x] (YBCO) films are grown by in-situ electron beam evaporation at high deposition rates (100 ∼ 350 Å/sec. The YBCO films are found to consist of two regions as a function of thickness: a region on the bottom with defect-free microstructure reflecting layer-by-layer growth and at the top a defected type reflecting island-growth. We suggested a new phase stability to explain this growth behavior, with Ba-Cu-O liquid fluxes. The films show critical current density greater than 2 MA/cm² on crystal substrates. Depth profiling of the transport properties (critical current density and resistivity) has been performed by etching the layers, elucidating that it is the island-growth layer where high critical current density is being carried. [ABSTRACT FROM AUTHOR]

Abstract. Bismuth titanate, Bi[sub 4]Ti[sub 3]O[sub 12], thin films were grown on IrO[sub 2]/SiO[sub 2]/Si substrates by radio-frequency magnetron sputtering. Crystallinity and microstructure of the films were characterized over a wide range of oxygen mixing ratio (OMR) during deposition. X-ray fluorescence spectra reveal that the cation content of the films is dependent upon the OMR, suggesting that control of Bi to Ti ratio is possible by the oxygen content in the sputtering atmosphere. Ruthertord backscattering spectrometry measurements also show that oxygen content of the BTO film grown with an OMR = 0.5 is close to a stoichiometric phase. In addition, Bi-O bonding chemistry is studied by X-ray photoelectron spectroscopy. Polarization vs. voltage loop shows that remnant polarization, P[sub r], is +12 micro C/cm[sup 2]. [ABSTRACT FROM AUTHOR]

Although the BNR system design assumes no sludge settling problems in the final settling tank, the fluctuation of daily loading and up to 40% of anaerobiosis in the BNR system would be considerable factors in determining the sludge settleability. The sludge volume index (SVI) is a classical parameter to examine the sludge settleability but it has a limited value to evaluate the overall settling characteristics. The extracellular polymer (ECP) content in sludge has long been considered as an indicator of biological flocculation in activated sludge process, but the skepticism on analytical accuracy limits the usage in settling study. This study focused on evaluating the BNR system performance related to the sludge settling characteristics under the controlled laboratory environment. A 5-stage BNR system (anaerobic-anoxic-3 stage oxic) was operated with the HRTs from 3.9 to 7.6 hours. In order to determine the sludge settling properties, both SVI and ECP content were monitored. The ECP contents in the sludge sample were measured by the slime-washing step followed by high- G centrifugation and sonication. The gel-electrophoresis was used to detect the DNA in the sonicated samples to determine the intracellular polymer contamination. It has been found that the anaerobiosis in the anaerobic and anoxic zone that consisted of 37% of reactor volume could not deteriorate the sludge settling properties even at the HRT of 3.9 hours. The SVI values of sludge taken from the reactor with the HRT of 7.2 hours averaged to less than 50 mL/gr. It was postulated that a fast settling sludge in the BNR system could not always ensure production of clear effluent. The sludge with very low SVI might not achieve a complete biological flocculation potential. In addition, the degree of denitrification in the BNR system could be related to the sludge settleability. [ABSTRACT FROM AUTHOR]

The in-vehicle volatile organic compound (VOC) concentrations during commutes have previously been measured in only one single interior sampling location, considering a sample collected in the single interior location as representative of overall VOC concentrations within an automobile. The present study evaluated if the potential differences in VOC concentrations occur in the automobiles' interior during idling and commuting under different driving conditions associated with the use of air cleaning devices (ACDs) and interior fan. The experiments were conducted under the low ventilation condition with the windows and the vent closed and the fan off. The difference of VOC concentrations between passenger side and back seat during idling was small. The variability of VOC concentrations with location inside automobiles while commuting was not significant at p<0.05, regardless of the use of ACDs and/or the interior fan, while inter-vehicle variability was significant at p<0.05. In addition, currently available ACDs equipped with activated carbon filters in Korea were ineffective at removing VOCs from the interior of automobiles. The concentrations of the two lightest ones of the target compounds, benzene and toluene, were significantly higher inside two vehicles than in the roadway air at p<0.05, while the in-vehicle and roadway concentrations of the other target compounds did not differ significantly at p<0.05 for both vehicles. The concentrations of all target VOCs, except benzene, were significantly higher (p<0.05) in the interior of older car than of newer car. Median in-vehicle concentrations of benzene, toluene, ethylbenzene, p-xylene, m-xylene, and o-xylene were 38.3, 107, 9.2, 7.8, 16.9, and 10.7 μg/m[SUP3], respectively. [ABSTRACT FROM AUTHOR]

Provides information on a study which examined the patterns of genetic diversity within the endangered Sarracenia rubra subspecies (ssp) alabamensis. Clarification of the genetic relationship between ssp. alabamensis and ssp. rubra; What the high genetic diversity found for ssp. alabamensis indicates; Genetic divergence between these subspecies; Description of the methodological approaches used in this study; Results of the study.

Presents a study on the genetic structure of pitcher plants, Sarracenia jonesii and Sarracenia oreophila (Sarraceniaceae). Species descriptions; Comparable levels of genetic diversity; Differences in allele frequencies.

Local surface potential of Cu2ZnSnSe4 thin-films was investigated by Kelvin probe force microscopy. The surface potential profile across grain boundaries (GBs) shows a rise of 200-600 meV at GBs in a Cu-poor and Zn-poor film with 3.8% efficiency, which means positively charged GBs. In contrast, the GBs in a Cu-poor and Zn-rich film with 2% efficiency exhibit lowering of surface potential by 40 meV. The results indicate that GBs of Cu2ZnSnSe4 films play a role for exciton separation and governing defects for high efficiency could be not only CuZn but also VCu as explained theoretical predictions. [ABSTRACT FROM AUTHOR]

The longitudinal and transverse strains were measured as a function of applied electric fields in a bulk ceramic sample of Pb0.99Nb0.02[(Zr0.57Sn0.43)0.94Ti0.06]0.98O3 at room temperature. Instead of a transverse contraction, a transverse expansion was observed in the electric-field-induced ferroelectric phase after the antiferroelectric-to-ferroelectric phase transition. Therefore, an auxetic behavior was established in monolithic ferroelectric polycrystalline ceramics under electrical loads. The behavior is characterized by a negative strain ratio that is analogous to the Poisson’s ratio. The transverse expansion leads to a large hydrostatic piezoelectric coefficient dh, which suggests new applications of antiferroelectric ceramics in piezoelectric devices. [ABSTRACT FROM AUTHOR]

The authors report growth media dependence of electrostatic force characteristics in Escherichia coli O157:H7 biofilm through local measurement by electrostatic force microscopy (EFM). The difference values of electrostatic interaction between the bacterial surface and the abiotic surface show an exponential decay behavior during biofilm development. In the EFM data, the biofilm in the low nutrient media shows a faster decay than the biofilm in the rich media. The surface potential in the bacterial cells was changed from 957 to 149 mV. Local characterization of extracellular materials extracted from the bacteria reveals the progress of the biofilm formation and functional complexities. [ABSTRACT FROM AUTHOR]

We report the synthesis of superconducting MgB[sub 2] thin films grown in situ by molecular-beam epitaxy. Mg-rich fluxes are deposited with B flux by electron-beam evaporation onto c-plane sapphire substrates. The films exhibit c-axis oriented peaks of MgB[sub 2], and a full width at half maximum of 3° in their rocking curves. In-plane alignment of MgB[sub 2] shows 12-fold symmetry, which is observed by the selected area diffraction pattern in transmission electron microscopy. The MgB[sub 2] films show a superconducting transition at 34.5 K with ΔT[sub c]<1 K. Even though the residual resistivity of the films is quite high (∼60 μΩ cm), the normal-state resistivity has a very similar temperature dependence but is five times larger than that of a single crystal, implying that conduction through the whole sample is imperfectly connected or inhomogeneous. Upper critical fields are obtained from measurement of the field dependence of the resistivity. It is estimated that the upper critical field at 20 K is more than 15 T, which is one of the largest values ever reported. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Evaluates results on domain retention in preferentially oriented PbZr[sub0.53]Ti[sub0.47]O[sub3] ferroelectric thin films on Pt and LaNiO[sub3] electrodes. Proposed mechanism underlying the process of ferroelectric thin film retention; Influence of bottom electrodes on retention of ferroelectric thin films; Remnant polarization as a function of time.

Examines the growth of Bi[sub 4]Ti[sub 3]O[sub 12] thin films by laser ablation on SrTiO[sub 3](110) and (110) substrates. Importance of substrate surface orientation in determining film electro-optic properties; Measurement of film linear birefringence; Observation of a ferroelectric phase transition.

CeO2 interlayers were used to control growth behavior of Bi4Ti3O12 thin films on MgO(001) substrates. The CeO2 layer grown at 740 °C had a preferential orientation with its c-axis normal to the film surface, so it could be used to grow an epitaxial Bi4Ti3O12(001)/CeO2(001)/MgO(001) heterostructure. On the other hand, the CeO2 layer grown at 650 °C showed a mixed texture of (001) and (111), and this interlayer enabled us to get a preferentially oriented Bi4Ti3O12(117)/CeO2(111)MgO(001) multilayer structure. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the epitaxial and preferentially oriented polycrystalline Bi[sub 4]Ti[sub 3]O[sub 12] thin films using La[sub 0.5]Sr[sub 0.5]CoO[sub 3] bottom electrodes. Explanation of growth behaviors using oxygen ion arrangements; Dependence of microstructures of the heterostructures on the substrates; Factors affecting leakage current behaviors the film.

Examines the growth of Bi[sub 4]Ti[sub 3]O[sub 12] thin films on temperature-cut sapphire substrate using pulsed laser deposition under various growth conditions. Components of various growth conditions; Effect of laser fluence on the growth behavior; Explanation on the growth behavior of preferential orientation in terms of atomic arrangement.

Investigates the growth of Bi[sub 4]Ti[sub 3]O[sub 12] thin films on indium-tin-oxide glass substrates by pulsed laser deposition. Importance of the annealing atmosphere as a growth parameter; Characteristics of films annealed in oxygen; Description of a film annealed in nitrogen; Structural description of films annealed in air.

Examines the growth of ferroelectric Bi[sub 4]Ti[sub 3]O[sub 12] thin films on magnesium oxide by pulsed laser deposition. Importance of laser fluence for film growth; Pattern of x-ray diffraction in films; Observation on the surface roughness of the films.

The mechanical stress-induced domain switching and energy dissipation in morphotropic phase boundary (1-x)(Bi1 - yLay)FeO3-xPbTiO3 during uniaxial compressive loading have been investigated at three different temperatures. The strain obtained was found to decrease with increasing lanthanum content, although a sharp increase in strain was observed for compositions doped with 7.5 and 10 at. % La. Increased domain switching was found in compositions with decreased tetragonality. This is discussed in terms of the competing influences of the amount of domain switching and the spontaneous strain on the macroscopic behavior under external fields. Comparison of the mechanically and electrically dissipated energy showed significant differences, discussed in terms of the different microscopic interactions of electric field and stress. [ABSTRACT FROM AUTHOR]

Prior studies have shown that a field-induced ferroelectricity in ceramics with general chemical formula (1-x-y)(Bi1/2Na1/2)TiO3–xBaTiO3–y(K0.5Na0.5)NbO3 and a very low remanent strain can produce very large piezoelectric strains. Here we show that both the longitudinal and transverse strains gradually change with applied electric fields even during the transition from the nonferroelectric to the ferroelectric state, in contrast to known Pb-containing antiferroelectrics. Hence, the volume change and, in turn, the phase transition can be affected using uniaxial compressive stresses, and the effect on ferroelectricity can thus be assessed. It is found that the 0.94(Bi1/2Na1/2)TiO3–0.05BaTiO3–0.01(K0.5Na0.5)NbO3 ceramic (largely ferroelectric), with a rhombohedral R3c symmetry, displays large ferroelectric domains, significant ferroelastic deformation, and large remanent electrical polarizations even at a 250 MPa compressive stress. In comparison, the 0.91(Bi1/2Na1/2)TiO3–0.07BaTiO3–0.02(K0.5Na0.5)NbO3 ceramic (largely nonferroelectric) possesses characteristics of a relaxor ferroelectric ceramic, including a pseudocubic structure, limited ferroelastic deformation, and low remanent polarization. The results are discussed with respect of the proposed antiferroelectric nature of the nonferroelectric state. [ABSTRACT FROM AUTHOR]

The article discusses the clinical practice guidelines established for genetic testing of patients with multiple endocrine neoplasia type 1 (MEN1). It says that the guidelines recommend regular clinical screening of individuals who have the tendency to develop MEN1-associated tumors for early detection of disease. It states that the responsibility to identify possible disease gene carriers among family members of patients with MEN1 should not be restricted to them.

Peripheral neuropathy is a frequent complication of type 2 diabetes mellitus (T2DM). We investigated whether human islet amyloid polypeptide (hIAPP), which forms pathogenic aggregates that damage pancreatic islet ß cells in T2DM, is involved in T2DM-associated peripheral neuropathy. In vitro, hIAPP incubation with sensory neurons reduced neurite outgrowth and increased levels of mitochondrial reactive oxygen species. hIAPP-transgenic mice, which have elevated plasma hIAPP levels without hyperglycemia, developed peripheral neuropathy as evidenced by pain-associated behavior and reduced intraepidermal nerve fiber (IENF) density. Similarly, hIAPP Ob/Ob mice, which have hyperglycemia in combination with elevated plasma hIAPP levels, had signs of neuropathy, although more aggravated. In wild-type mice, intraplantar and intravenous hIAPP injections induced long-lasting allodynia and decreased IENF density. Non-aggregating murine IAPP, mutated hIAPP (pramlintide), or hIAPP with pharmacologically inhibited aggregation did not induce these effects. T2DM patients had reduced IENF density and more hIAPP oligomers in the skin compared with non-T2DM controls. Thus, we provide evidence that hIAPP aggregation is neurotoxic and mediates peripheral neuropathy in mice. The increased abundance of hIAPP aggregates in the skin of T2DM patients supports the notion that hIAPP is a potential contributor to T2DM neuropathy in humans. [ABSTRACT FROM AUTHOR]

A correction to the article "Induction of Interleukin-8 Preserves the Angiogenic Response in HIF-1α–Deficient Colon Cancer Cells" that was published in the February 2006 issue is presented.