Sample records for colloidal array cca
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Crystalline Colloidal Arrays in Polymer Matrices
NASA Technical Reports Server (NTRS)
Sunkara, Hari B.; Penn, B. G.; Frazier, D. O.; Ramachandran, N.
1997-01-01
Crystalline Colloidal Arrays (CCA, also known as colloidal crystals), composed of aqueous or nonaqueous dispersions of self-assembled nanosized polymer colloidal spheres, are emerging toward the development of advanced optical devices for technological applications. The spontaneous self assembly of polymer spheres in a dielectric medium results from the electrostatic repulsive interaction between particles of uniform size and charge distribution. In a way similar to atomic crystals that diffract X-rays, CCA dispersions in thin quartz cells selectively and efficiently Bragg diffract the incident visible light. The reason for this diffraction is because the lattice (body or face centered cubic) spacing is on the order of the wavelength of visible light. Unlike the atomic crystals that diffract a fixed wavelength, colloidal crystals in principle, depending on the particle size, particle number and charge density, can diffract W, Vis or IR light. Therefore, the CCA dispersions can be used as laser filters. Besides, the diffraction intensity depends on the refractive index mismatch between polymer spheres and dielectric medium; therefore, it is possible to modulate incident light intensities by manipulating the index of either the spheres or the medium. Our interest in CCA is in the fabrication of all-optical devices such as optical switches, limiters, and spatial light modulators for optical signal processing. The two major requirements from a materials standpoint are the incorporation of suitable nonlinear optical materials (NLO) into polymer spheres which will allow us to alter the refractive index of the spheres by intense laser radiation, and preparation of solid CCA filters which can resist laser damage. The fabrication of solid composite filters not only has the advantage that the films are easier to handle, but also the arrays in solid films are more robust than in liquid media. In this paper, we report the photopolymerization process used to trap CCA in polymer matrices, the factors which affect the optical diffraction qualities of resulting polymer films, and methods to improve the efficiencies of solid optical filters. Before this, we also present the experimental demonstration, of controlling the optical diffraction intensities from aqueous CCA dispersions by varying the temperature, which establishes the feasibility of fabricating all-optical switching devices with nonlinear periodic array structures.
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Bohn, Justin J.; Ben-Moshe, Matti; Tikhonov, Alexander; Qu, Dan; Lamont, Daniel N.
2010-01-01
We developed a straightforward method to form non close-packed highly ordered fcc direct and inverse opal silica photonic crystals. We utilize an electrostatically self assembled crystalline colloidal array (CCA) template formed by monodisperse, highly charged polystyrene particles. We then polymerize a hydrogel around the CCA (PCCA) and condense the silica to form a highly ordered silica impregnated (siPCCA) photonic crystal. Heating at 450 °C removes the organic polymer leaving a silica inverse opal structure. By altering the colloidal particle concentration we independently control the particle spacing and the wall thickness of the inverse opal photonic crystals. This allows us to control the optical dielectric constant modulation in order to optimize the diffraction; the dielectric constant modulation is controlled independently of the photonic crystal periodicity. These fcc photonic crystals are better ordered than typical close-packed photonic crystals because their self assembly utilizes soft electrostatic repulsive potentials. We show that colloidal particle size and charge polydispersity has modest impact on ordering, in contrast to that for close-packed crystals. PMID:20163800
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Photonic crystal borax competitive binding carbohydrate sensing motif†
Cui, Qingzhou; Muscatello, Michelle M. Ward; Asher, Sanford A.
2009-01-01
We developed a photonic crystal sensing method for diol containing species such as carbohydrates based on a poly(vinyl alcohol) (PVA) hydrogel containing an embedded crystalline colloidal array (CCA). The polymerized CCA (PCCA) diffracts visible light. We show that in the presence of borax the diffraction wavelength shifts as the concentration of glucose changes. The diffraction shifts result from the competitive binding of glucose to borate, which reduces the concentration of borate bound to the PVA diols. PMID:19381378
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Colloidal crystal growth monitored by Bragg diffraction interference fringes.
Bohn, Justin J; Tikhonov, Alexander; Asher, Sanford A
2010-10-15
We monitored the crystal growth kinetics of crystallization of a shear melted crystalline colloidal array (CCA). The fcc CCA heterogeneously nucleates at the flow cell wall surface. We examined the evolution of the (1 1 1) Bragg diffraction peak, and, for the first time, quantitatively monitored growth by measuring the temporal evolution of the Bragg diffraction interference fringes. Modeling of the evolution of the fringe patterns exposes the time dependence of the increasing crystal thickness. The initial diffusion-driven linear growth is followed by ripening-driven growth. Between 80 and 90 microM NaCl concentrations the fcc crystals first linearly grow at rates between 1.9 and 4.2 microm/s until they contact homogeneously nucleated crystals in the bulk. At lower salt concentrations interference fringes are not visible because the strong electrostatic interactions between particles result in high activation barriers, preventing defect annealing and leading to a lower crystal quality. The fcc crystals melt to a liquid phase at >90 microM NaCl concentrations. Increasing NaCl concentrations slow the fcc CCA growth rate consistent with the expectation of the classical Wilson-Frenkel growth theory. The final thickness of wall-nucleated CCA, that is determined by the competition between growth of heterogeneously and homogenously nucleated CCA, increases with higher NaCl concentrations. Copyright 2010 Elsevier Inc. All rights reserved.
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Polymerized PolyHEMA photonic crystals: pH and ethanol sensor materials.
Xu, Xiangling; Goponenko, Alexander V; Asher, Sanford A
2008-03-12
The surface of monodisperse silica particles synthesized using the Stober process were coated with a thin layer of polystyrene. Surface charge groups were attached by a grafting polymerization of styrene sulfonate. The resulting highly charged monodisperse silica particles self-assemble into crystalline colloidal arrays (CCA) in deionized water. We polymerized hydroxyethyl methacrylate (HEMA) around the CCA to form a HEMA-polymerized crystalline colloidal array (PCCA). Hydrofluoric acid was utilized to etch out the silica particles to produce a three-dimensional periodic array of voids in the HEMA PCCA. The diffraction from the embedded CCA sensitively monitors the concentration of ethanol in water because the HEMA PCCA shows a large volume dependence on ethanol due to a decreased Flory-Huggins mixing parameter. Between pure water and 40% ethanol the diffraction shifts across the entire visible spectral region. We accurately modeled the dependence of the diffraction wavelength on ethanol concentration using Flory theory. We also fabricated a PCCA (which responds to pH changes in both low and high ionic strength solutions) by utilizing a second polymerization to incorporate carboxyl groups into the HEMA PCCA. We were also able to model the pH dependence of diffraction of the HEMA PCCA by using Flory theory. An unusual feature of the pH response is a hysteresis in response to titration to higher and lower pH. This hysteresis results from the formation of a Donnan potential at high pH which shifts the ionic equilibrium. The kinetics of equilibration is very slow due to the ultralow diffusion constant of protons in the carboxylated PCCA as predicted earlier by the Tanaka group.
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Studies on photonic crystal composites: Fabrication and applications
NASA Astrophysics Data System (ADS)
Ying, Yurong
There is considerable interest in developing three-dimensional ordered dielectric structures because of their unique optical property, the photonic band gap. A material containing this photonic band gap can be used to control the propagation of electromagnetic waves. This characteristic can be utilized in fabricating a number of diffractive optical devices. A crystalline colloidal array (CCA) is one such three-dimensional ordered dielectric structure, formed through the self-assembly of monodispersed, surface-charged colloidal particles when they are dispersed in a polar liquid medium. Previous work has demonstrated that monodispersed, negatively charged polystyrene spheres can self-assemble into a face-centered cubic (fcc) structure when they are dispersed in a polar medium. This fee lattice can be locked in a hydrogel-based polymeric network and then encapsulated into a water-free elastomer network. These photonic crystal hydrogel films exhibit a solvatochromic effect. A method has been developed for creating patterns in photonic crystal hydrogel films based on this solvatochromic effect via a direct photopolymerization process. The multicolor pattern generation induced by this method resulted in macro- and micropatterns with a large color contrast, i.e. the difference between the patterned area and the background is greater than 150 nm. Unfortunately, CCA systems often exhibit intrinsic and extrinsic defects. To reduce the extrinsic defects incurred during the film fabrication process, a modified lithographic technique was developed to fabricate a high quality, large area, ca. 1 cm2 and a robust, water-free photonic band gap composite film having a thickness of 35 mum. The optical properties of these composite films change in response to their mechanical deformation. These robust films can change shape and recover after stretching or compression without destroying the order of the crystal. These thin films have a high sensitivity to a pressure variation when they are employed as a window in a pressure cell. In total, a 212 nm stop band shift was achieved as the pressure changed from 0 psi to 2.9 psi. Utilizing its mechanochromic response, this thin PBG composite film also has been employed as part of a resonant cavity to develop a thin film organic laser with a tunable emission wavelength of 32 nm. Since the refractive-index contrast between the polystyrene spheres and the polymeric matrix is relatively low, only a narrow stop band can be observed. To increase the contrast, CCA formed using organic dye doped polystyrene spheres and a crystalline colloidal array templated inverse opal was successfully synthesized.
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NASA Astrophysics Data System (ADS)
Cho, I.; Tada, T.; Shinozaki, Y.
2005-12-01
We have developed a Centerless Circular Array (CCA) method of microtremor exploration, an algorithm that enables to estimate phase velocities of Rayleigh waves by analyzing vertical-component records of microtremors that are obtained with an array of three or five seismic sensors placed around a circumference. Our CCA method shows a remarkably high performance in long-wavelength ranges because, unlike the frequency-wavenumber spectral method, our method does not resolve individual plane-wave components in the process of identifying phase velocities. Theoretical considerations predict that the resolving power of our CCA method in long-wavelength ranges depends upon the SN ratio, or the ratio of power of the propagating components to that of the non-propagating components (incoherent noise) contained in the records from the seismic array. The applicability of our CCA method to small-sized arrays on the order of several meters in radius has already been confirmed in our earlier work (Cho et al., 2004). We have deployed circular seismic arrays of different sizes at test sites in Japan where the underground structure is well documented through geophysical exploration, and have applied our CCA method to microtremor records to estimate phase velocities of Rayleigh waves. The estimates were then checked against "model" phase velocities that are derived from theoretical calculations. For arrays of 5, 25, 300 and 600 meters in radii, the estimated and model phase velocities demonstrated fine agreement within a broad wavelength range extending from a little larger than 3r (r: the array radius) up to at least 40r, 14r, 42r and 9r, respectively. This demonstrates the applicability of our CCA method to arrays on the order of several to several hundreds of meters in radii, and also illustrates, in a typical way, the markedly high performance of our CCA method in long-wavelength ranges. We have also invented a mathematical model that enables to evaluate the SN ratio in a given microtremor field, and have applied it to real data. Theory predicts that our CCA method underestimates the phase velocities when noise is present. Using the evaluated SN ratio and the phase velocity dispersion curve model, we have calculated the apparent values of phase velocities which theory expects should be obtained by our CCA method in long-wavelength ranges, and have confirmed that the outcome agreed very well with the phase velocities estimated from real data. This demonstrates that the mathematical assumptions, on which our CCA method relies, remains valid over a wide range of wavelengths which we are examining, and also implies that, even in the absence of a priori knowledge of the phase velocity dispersion curve, the SN ratio evaluated with our mathematical model could be used to identify the resolution limit of our CCA method in long-wavelength ranges. We have thus been able to demonstrate, on the basis of theoretical considerations and real data analysis, both the capabilities and limitations of our CCA method.
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Structural Coloration of a Colloidal Amorphous Array is Intensified by Carbon Nanolayers.
Takeoka, Yukikazu; Iwata, Masanori; Seki, Takahiro; Nueangnoraj, Khanin; Nishihara, Hirotomo; Yoshioka, Shinya
2018-04-10
In this study, we introduce the possibility of applying a colloidal amorphous array composed of fine silica particles as a structural-color material to invisible information technology. The appearance of a thick filmlike colloidal amorphous array formed from fine silica particles is considerably influenced by incoherent light scattering across the entire visible region. Therefore, regardless of the diameter of the fine silica particles, the thick colloidal amorphous array exhibits a white color to the naked eye. When carbon is uniformly deposited in the colloidal amorphous array by a pressure-pulsed chemical vapor deposition method, incoherent light scattering in the colloidal amorphous array is suppressed. As a result, coherent light scattering due to the short-range order in the colloidal amorphous array becomes conspicuous and the array exhibits a vivid structural color. As structures, such as letters and pictures, can be drawn using this technology, the colloidal amorphous array as a structural-colored material may also be applicable for invisible information technology.
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NASA Astrophysics Data System (ADS)
Dunning, Peter David
A colloidal suspension is a small constituent of insoluble solid particles suspended in a liquid medium. Control over the wetting, evaporation, and deposition patterns left by colloidal suspensions is valuable in many biological, medical, industrial, and agricultural applications. Understanding the governing principles of wetting and evaporative phenomena of these colloidal suspensions may lead to greater control over resultant deposition patterns. Perhaps the most familiar pattern forms when an initially heterogeneous colloidal suspension leaves a dark ring pattern at the edge of a drop. This pattern is referred to as a coffee-stain and it can be seen from dried droplets of spilled coffee. This coffee-stain effect was first investigated by Deegan et. al. who discovered that these patterns occur when outward radial flows driven by evaporation at the triple contact line dominate over other effects. While the presence of coffee-stain patterns is undesirable in many printing and medical diagnostic processes, it can also be advantageous in the production of low cost transparent conductive films, the deposition of metal vapor, and the manipulation of biological structures. Controlling the interactions between the substrate, liquid, vapor, and particles can lead to control over the size and morphology of evaporative deposition patterns left by aqueous colloidal suspensions. Several methods have been developed to control the evaporation of colloidal suspensions to either suppress or enhance the coffee stain effect. Electrowetting on Dielectric (EWOD) is one promising method that has been used to control colloidal depositions by applying either an AC or DC electric field. EWOD actuation has the potential to dynamically control colloidal deposition left by desiccated droplets to either suppress or enhance the coffee stain effect. It may also allow for independent control of the fluidic interface and deposition of particles via electrowetting and electrokinetic forces. Implementation of this technique requires that the colloidal droplet be separated from the active electrode by a dielectric layer to prevent electrolysis. A variety of polymer layers have been used in EWOD devices for a variety of applications. In applications that involve desiccation of colloidal suspensions, the material for this layer should be chosen carefully as it can play an important role in the resulting deposition pattern. An experimental method to monitor the transient evolution of the shape of an evaporating colloidal droplet and optically quantify the resultant deposition pattern is presented. Unactuated colloidal suspensions will be desiccated on a variety of substrates commonly used in EWOD applications. Transient image profiles and particle deposition patterns are examined for droplets containing fluorescent micro-particles. Qualitative and quantitative comparisons of these results will be used to compare multiple different cases in an effort to provide insight into the effects of polymer selection on the drying dynamics and resultant deposition patterns of desiccated colloidal materials. It was found that the equilibrium and receding contact angles between the surface and the droplet play a key role in the evaporation dynamics and the resulting deposition patterns left by a desiccated colloidal suspension. The equilibrium contact angle controls the initial contact diameter for a droplet of a given volume. As a droplet on a surface evaporates, the evolution of the interface shape and the contact diameter can generally be described by three different regimes. The Constant Contact Radius (CCR) regime occurs when the contact line is pinned while the contact angle decreases. The Constant Contact Angle (CCA) regime occurs when the contact line recedes while the contact angle remains constant. The Mixed regime occurs when the contact radius and angle both reduce over time. The presence of the CCA regime allows the contact line to recede creating a more uniform deposition. However, not all droplets move into the CCA regime. Some remain in the CCR regime creating a coffee-stain pattern. In order to transition into the CCA regime, the dynamic contact angle of the droplet must be reduced to an angle close to the receding contact angle. Transient interface shapes and deposition patterns were examined on four surfaces: (i) Glass, (ii) Kapton HN polyimide tape, (iii) SU-8 3005, and (iv) Teflon AF. Glass has a low equilibrium contact angle and a very low receding contact angle resulting in a large uniform coffee-stain deposition. Kapton HN and SU-8 3005 have similar equilibrium contact angles that result in similar initial contact diameters. However, Kapton HN pins at that initial diameter due to a low receding contact angle producing a smaller more intense coffee-stain. SU-8 3005 has a large receding contact angle that allows for the transition into the CCA regime which results in a smaller, more uniform, and more intense spot. Teflon AF has the largest equilibrium and receding contact angle producing the smallest, most uniform, and most intense spot. Results presented here suggest that a lower receding contact angle is beneficial in areas where the coffee-stain effect needs to be enhanced while a larger receding contact angle is beneficial in areas where the coffee-stain needs to be suppressed. Preliminary results are also presented examining droplets actuated via AC electrowetting to examine the effect of electrode geometry and applied voltage on electrowetting behavior and colloidal depositions in these cases. It was found that the Young-Lippmann equation needs to be modified to satisfy the modified capacitance per unit area of a system with different electrode geometries.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Choudhury, S.; Agyeman-Budu, D. N.; Woll, A. R.
Confocal X-ray fluorescence imaging (CXFI) and confocal X-ray absorption spectroscopy (CXAS) respectively enable the study of three dimensionally resolved localization and speciation of elements. Applied to a thick sample, essentially any volume element of interest within the X-ray fluorescence escape depth can be examined without the need for physical thin sectioning. To date, X-ray confocal detection generally has employed a polycapillary optic in front of the detector to collect fluorescence from the probe volume formed at the intersection of its focus with the incident microfocus beam. This work demonstrates the capability of a novel Collimating Channel Array (CCA) optic inmore » providing an improved and essentially energy independent depth resolution approaching 2 μm. By presenting a comparison of elemental maps of archaeological bone collected without confocal detection, and with polycapillary- and CCA-based confocal detection, this study highlights the strengths and limitations of each mode. Unlike the polycapillary, the CCA shows similar spatial resolution in maps for both low (Ca) and high (Pb and Sr) energy X-ray fluorescence, thus illustrating the energy independent nature of the CCA optic resolution. While superior spatial resolution is demonstrated for all of these elements, the most significant improvement is observed for Ca, demonstrating the advantage of employing the CCA optic in examining light elements. In addition to CXFI, this configuration also enables the collection of Pb L3 CXAS data from micro-volumes with dimensions comparable to bone microstructures of interest. Our CXAS result, which represents the first CCA-based biological CXAS, demonstrates the ability of CCA optics to collect site specific spectroscopic information. The demonstrated combination of site-specific elemental localization and speciation data will be useful in diverse fields.« less
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A Novel Predictive Equation for Potential Diagnosis of Cholangiocarcinoma
Kraiklang, Ratthaphol; Pairojkul, Chawalit; Khuntikeo, Narong; Imtawil, Kanokwan; Wongkham, Sopit; Wongkham, Chaisiri
2014-01-01
Cholangiocarcinoma (CCA) is the second most common-primary liver cancer. The difficulties in diagnosis limit successful treatment of CCA. At present, histological investigation is the standard diagnosis for CCA. However, there are some poor-defined tumor tissues which cannot be definitively diagnosed by general histopathology. As molecular signatures can define molecular phenotypes related to diagnosis, prognosis, or treatment outcome, and CCA is the second most common cancer found after hepatocellularcarcinoma (HCC), the aim of this study was to develop a predictive model which differentiates CCA from HCC and normal liver tissues. An in-house PCR array containing 176 putative CCA marker genes was tested with the training set tissues of 20 CCA and 10 HCC cases. The molecular signature of CCA revealed the prominent expression of genes involved in cell adhesion and cell movement, whereas HCC showed elevated expression of genes related to cell proliferation/differentiation and metabolisms. A total of 69 genes differentially expressed in CCA and HCC were optimized statistically to formulate a diagnostic equation which distinguished CCA cases from HCC cases. Finally, a four-gene diagnostic equation (CLDN4, HOXB7, TMSB4 and TTR) was formulated and then successfully validated using real-time PCR in an independent testing set of 68 CCA samples and 77 non-CCA controls. Discrimination analysis showed that a combination of these genes could be used as a diagnostic marker for CCA with better diagnostic parameters with high sensitivity and specificity than using a single gene marker or the usual serum markers (CA19-9 and CEA). This new combination marker may help physicians to identify CCA in liver tissues when the histopathology is uncertain. PMID:24586698
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Iwata, Masanori; Teshima, Midori; Seki, Takahiro; Yoshioka, Shinya; Takeoka, Yukikazu
2017-07-01
Inspired by Steller's jay, which displays angle-independent structural colors, angle-independent structurally colored materials are created, which are composed of amorphous arrays of submicrometer-sized fine spherical silica colloidal particles. When the colloidal amorphous arrays are thick, they do not appear colorful but almost white. However, the saturation of the structural color can be increased by (i) appropriately controlling the thickness of the array and (ii) placing the black background substrate. This is similar in the case of the blue feather of Steller's jay. Based on the knowledge gained through the biomimicry of structural colored materials, colloidal amorphous arrays on the surface of a black particle as the core particle are also prepared as colorful photonic pigments. Moreover, a structural color on-off system is successfully built by controlling the background brightness of the colloidal amorphous arrays. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Burkert, Klaus; Neumann, Thomas; Wang, Jianjun; Jonas, Ulrich; Knoll, Wolfgang; Ottleben, Holger
2007-03-13
Photonic crystals and photonic band gap materials with periodic variation of the dielectric constant in the submicrometer range exhibit unique optical properties such as opalescence, optical stop bands, and photonic band gaps. As such, they represent attractive materials for the active elements in sensor arrays. Colloidal crystals, which are 3D gratings leading to Bragg diffraction, are one potential precursor of such optical materials. They have gained particular interest in many technological areas as a result of their specific properties and ease of fabrication. Although basic techniques for the preparation of regular patterns of colloidal crystals on structured substrates by self-assembly of mesoscopic particles are known, the efficient fabrication of colloidal crystal arrays by simple contact printing has not yet been reported. In this article, we present a spotting technique used to produce a microarray comprising up to 9600 single addressable sensor fields of colloidal crystal structures with dimensions down to 100 mum on a microfabricated substrate in different formats. Both monodisperse colloidal crystals and binary colloidal crystal systems were prepared by contact printing of polystyrene particles in aqueous suspension. The array morphology was characterized by optical light microscopy and scanning electron microscopy, which revealed regularly ordered crystalline structures for both systems. In the case of binary crystals, the influence of the concentration ratio of the large and small particles in the printing suspension on the obtained crystal structure was investigated. The optical properties of the colloidal crystal arrays were characterized by reflection spectroscopy. To examine the stop bands of the colloidal crystal arrays in a high-throughput fashion, an optical setup based on a CCD camera was realized that allowed the simultaneous readout of all of the reflection spectra of several thousand sensor fields per array in parallel. In agreement with Bragg's relation, the investigated arrays exhibited strong opalescence and stop bands in the expected wavelength range, confirming the successful formation of highly ordered colloidal crystals. Furthermore, a narrow distribution of wavelength-dependent stop bands across the sensor array was achieved, demonstrating the capability of producing highly reproducible crystal spots by the contact printing method with a pintool plotter.
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Fabrication of non-hexagonal close packed colloidal array on a substrate by transfer
NASA Astrophysics Data System (ADS)
Banik, Meneka; Mukherjee, Rabibrata
Self-organized colloidal arrays find application in fabrication of solar cells with advanced light management strategies. We report a simple spincoating based approach for fabricating two dimensional colloidal crystals with hexagonal and non-hexagonal close packed assembly on flat and nanopatterned substrates. The non-HCP arrays were fabricated by spin coating the particles onto soft lithographically fabricated substrates. The substrate patterns impose directionality to the particles by confining them within the grooves. We have developed a technique by which the HCP and non-HCP arrays can be transferred to any surface. For this purpose the colloidal arrays were fabricated on a UV degradable PMMA layer, resulting in transfer of the particles on UV exposure. This allows the colloidal structures to be transported across substrates irrespective of their surface energy, wettability or morphology. Since the particles are transferred without exposing it to any kind of chemical or thermal environment, it can be utilized for placing particles on top of thin film solar cells for improving their absorption efficiency.
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Annexin A1: A new immunohistological marker of cholangiocarcinoma
Hongsrichan, Nuttanan; Rucksaken, Rucksak; Chamgramol, Yaovalux; Pinlaor, Porntip; Techasen, Anchalee; Yongvanit, Puangrat; Khuntikeo, Narong; Pairojkul, Chawalit; Pinlaor, Somchai
2013-01-01
AIM: To evaluate a new immunohistological marker, annexin A1 (ANXA1), in cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC). METHODS: Expression of ANXA1 protein was investigated in liver tissues from patients with CCA and HCC by immunohistochemistry. Its expression on differences stages of tumor development was investigated in hamster CCA tissues induced by Opisthorchis viverrini and N-nitrosodimethylamine. Moreover, mRNA expression of ANXA1 was assessed in CCA cell lines by quantitative real-time polymerase chain reaction and silencing of ANXA1 gene expression using small interfering RNA. RESULTS: In human CCA tissue arrays, immunohistochemical analysis revealed that the positive expression of ANXA1 was 94.1% (64/68 cases) consisting of a high expression (66.2%, 45/68 cases) and a low expression (33.8%, 23/68 cases). However, expression of ANXA1 protein was negative in all histologic patterns for HCC (46/46 cases) and healthy individuals (6/6 cases). In hamster with opisthorchiasis-associated CCA, the expression of ANXA1 was observed in the cytoplasm of inflammatory cells, bile duct epithelia and tumor cells. Grading scores of ANXA1 expression were significantly increased with tumor progression. In addition, mRNA expression of ANXA1 significantly increased in all of the various CCA cell lines tested compared to an immortalized human cholangiocyte cell line (MMNK1). Suppressing the ANXA1 gene significantly reduced the matrix metalloproteinase (MMP) 2 and MMP9, and transforming growth factor-β genes, but increased nuclear factor-κB gene expression. CONCLUSION: ANXA1 is highly expressed in CCA, but low in HCC, suggesting it may serve as a new immunohistochemical marker of CCA. ANXA1 may play a role in opisthorchiasis-associated cholangiocarcinogenesis. PMID:23674846
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Pak, Jhang Ho; Bashir, Qudsia; Kim, In Ki; Hong, Sung-Jong; Maeng, Sejung; Bahk, Young Yil; Kim, Tong-Soo
2017-06-01
Cholangiocarcinoma (CCA) is a slow-growing but highly metastatic cancer. Its metastatic potential largely explains its high mortality rate. A recognized risk factor for CCA development is infection with the liver flukes Opisthorchis viverrini and Clonorchis sinensis. We previously reported that the excretory-secretory products (ESPs) of C. sinensis promoted the three-dimensional aggregation and invasion of CCA cells. In the present study, a quantitative real-time PCR array of extracellular matrix (ECM) and adhesion molecules was used to examine the regulatory mechanism of ESP-mediated CCA cell migration and invasion. In particular, the expression levels of integrin α isoforms and β4 were upregulated in response to ESPs. Increased expression of integrin β4 was probably correlated with activation of focal adhesion kinase (FAK) and the steroid receptor coactivator (Src) family kinase and the subsequent activation of two downstream focal adhesion molecules, paxillin and vinculin. Moreover, inhibition of FAK/Src activation reduced paxillin and vinculin phosphorylation and attenuated ESP-induced CCA cell migration and invasion. These findings suggest that the integrin β4-FAK/Src signaling axis may play a crucial role in clonorchiasis-associated CCA metastasis during tumor progression. Copyright © 2017 Elsevier B.V. All rights reserved.
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Size dependence in tunneling spectra of PbSe quantum-dot arrays.
Ou, Y C; Cheng, S F; Jian, W B
2009-07-15
Interdot Coulomb interactions and collective Coulomb blockade were theoretically argued to be a newly important topic, and experimentally identified in semiconductor quantum dots, formed in the gate confined two-dimensional electron gas system. Developments of cluster science and colloidal synthesis accelerated the studies of electron transport in colloidal nanocrystal or quantum-dot solids. To study the interdot coupling, various sizes of two-dimensional arrays of colloidal PbSe quantum dots are self-assembled on flat gold surfaces for scanning tunneling microscopy and scanning tunneling spectroscopy measurements at both room and liquid-nitrogen temperatures. The tip-to-array, array-to-substrate, and interdot capacitances are evaluated and the tunneling spectra of quantum-dot arrays are analyzed by the theory of collective Coulomb blockade. The current-voltage of PbSe quantum-dot arrays conforms properly to a scaling power law function. In this study, the dependence of tunneling spectra on the sizes (numbers of quantum dots) of arrays is reported and the capacitive coupling between quantum dots in the arrays is explored.
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NASA Astrophysics Data System (ADS)
Wu, Ling; Nishi, Hiroyasu; Tatsuma, Tetsu
2015-10-01
Photoelectrodes based on plasmonic Au semishell (or halfshell) arrays are developed. A colloidal crystal consisting of SiO2@TiO2 core-shell particles is prepared on a TiO2-coated transparent electrode. A Au semishell (or halfshell) array is deposited by sputtering or evaporation on the colloidal crystal. An electrode with the semishell (or halfshell) array exhibits negative photopotential shifts and anodic photocurrents under visible light at 500-800 nm wavelengths in an aqueous electrolyte containing an electron donor. In particular, hydroquinone and ethanol are good electron donors. The photocurrents can be explained in terms of plasmon-induced charge separation at the Au-TiO2 interface.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Ling; Nishi, Hiroyasu; Tatsuma, Tetsu, E-mail: tatsuma@iis.u-tokyo.ac.jp
2015-10-01
Photoelectrodes based on plasmonic Au semishell (or halfshell) arrays are developed. A colloidal crystal consisting of SiO{sub 2}@TiO{sub 2} core-shell particles is prepared on a TiO{sub 2}-coated transparent electrode. A Au semishell (or halfshell) array is deposited by sputtering or evaporation on the colloidal crystal. An electrode with the semishell (or halfshell) array exhibits negative photopotential shifts and anodic photocurrents under visible light at 500-800 nm wavelengths in an aqueous electrolyte containing an electron donor. In particular, hydroquinone and ethanol are good electron donors. The photocurrents can be explained in terms of plasmon-induced charge separation at the Au-TiO{sub 2} interface.
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Autonomous colloidal crystallization in a galvanic microreactor
NASA Astrophysics Data System (ADS)
Punckt, Christian; Jan, Linda; Jiang, Peng; Frewen, Thomas A.; Saville, Dudley A.; Kevrekidis, Ioannis G.; Aksay, Ilhan A.
2012-10-01
We report on a technique that utilizes an array of galvanic microreactors to guide the assembly of two-dimensional colloidal crystals with spatial and orientational order. Our system is comprised of an array of copper and gold electrodes in a coplanar arrangement, immersed in a dilute hydrochloric acid solution in which colloidal micro-spheres of polystyrene and silica are suspended. Under optimized conditions, two-dimensional colloidal crystals form at the anodic copper with patterns and crystal orientation governed by the electrode geometry. After the aggregation process, the colloidal particles are cemented to the substrate by co-deposition of reaction products. As we vary the electrode geometry, the dissolution rate of the copper electrodes is altered. This way, we control the colloidal motion as well as the degree of reaction product formation. We show that particle motion is governed by a combination of electrokinetic effects acting directly on the colloidal particles and bulk electrolyte flow generated at the copper-gold interface.
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Halpern, Aaron R; Corn, Robert M
2013-02-26
A novel low-cost nanoring array fabrication method that combines the process of lithographically patterned nanoscale electrodeposition (LPNE) with colloidal lithography is described. Nanoring array fabrication was accomplished in three steps: (i) a thin (70 nm) sacrificial nickel or silver film was first vapor-deposited onto a plasma-etched packed colloidal monolayer; (ii) the polymer colloids were removed from the surface, a thin film of positive photoresist was applied, and a backside exposure of the photoresist was used to create a nanohole electrode array; (iii) this array of nanoscale cylindrical electrodes was then used for the electrodeposition of gold, silver, or nickel nanorings. Removal of the photoresist and sacrificial metal film yielded a nanoring array in which all of the nanoring dimensions were set independently: the inter-ring spacing was fixed by the colloidal radius, the radius of the nanorings was controlled by the plasma etching process, and the width of the nanorings was controlled by the electrodeposition process. A combination of scanning electron microscopy (SEM) measurements and Fourier transform near-infrared (FT-NIR) absorption spectroscopy were used to characterize the nanoring arrays. Nanoring arrays with radii from 200 to 400 nm exhibited a single strong NIR plasmonic resonance with an absorption maximum wavelength that varied linearly from 1.25 to 3.33 μm as predicted by a simple standing wave model linear antenna theory. This simple yet versatile nanoring array fabrication method was also used to electrodeposit concentric double gold nanoring arrays that exhibited multiple NIR plasmonic resonances.
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Transferable ordered ni hollow sphere arrays induced by electrodeposition on colloidal monolayer.
Duan, Guotao; Cai, Weiping; Li, Yue; Li, Zhigang; Cao, Bingqiang; Luo, Yuanyuan
2006-04-13
We report an electrochemical synthesis of two-dimensionally ordered porous Ni arrays based on polystyrene sphere (PS) colloidal monolayer. The morphology can be controlled from bowl-like to hollow sphere-like structure by changing deposition time under a constant current. Importantly, such ordered Ni arrays on a conducting substrate can be transferred integrally to any other desired substrates, especially onto an insulting substrate or curved surface. The magnetic measurements of the two-dimensional hollow sphere array show the coercivity values of 104 Oe for the applied field parallel to the film, and 87 Oe for the applied field perpendicular to the film, which is larger than those of bulk Ni and hollow Ni submicrometer-sized spheres. The formation of hollow sphere arrays is attributed to preferential nucleation on the interstitial sites between PS in the colloidal monolayer and substrate, and growth along PSs' surface. The transferability of the arrays originates from partial contact between the Ni hollow spheres and substrate. Such novel Ni ordered nanostructured arrays with transferability and high magnetic properties should be useful in applications such as data storage, catalysis, and magnetics.
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Zhang, Xun; Zhang, Junhu; Zhu, Difu; Li, Xiao; Zhang, Xuemin; Wang, Tieqiang; Yang, Bai
2010-12-07
We present a novel and simple method to fabricate two-dimensional (2D) poly(styrene sulfate) (PSS, negatively charged) colloidal crystals on a positively charged substrate. Our strategy contains two separate steps: one is the three-dimensional (3D) assembly of PSS particles in ethanol, and the other is electrostatic adsorption in water. First, 3D assembly in ethanol phase eliminates electrostatic attractions between colloids and the substrate. As a result, high-quality colloidal crystals are easily generated, for electrostatic attractions are unfavorable for the movement of colloidal particles during convective self-assembly. Subsequently, top layers of colloidal spheres are washed away in the water phase, whereas well-packed PSS colloids that are in contact with the substrate are tightly linked due to electrostatic interactions, resulting in the formation of ordered arrays of 2D colloidal spheres. Cycling these processes leads to the layer-by-layer assembly of 3D colloidal crystals with controllable layers. In addition, this strategy can be extended to the fabrication of patterned 2D colloidal crystals on patterned polyelectrolyte surfaces, not only on planar substrates but also on nonplanar substrates. This straightforward method may open up new possibilities for practical use of colloidal crystals of excellent quality, various patterns, and controllable fashions.
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Design of intelligent mesoscale periodic array structures utilizing smart hydrogel
NASA Technical Reports Server (NTRS)
Sunkara, H. B.; Penn, B. G.; Frazier, D. O.; Weissman, J. M.; Asher, S. A.
1996-01-01
Mesoscale Periodic Array Structures (MPAS, also known as crystalline colloidal arrays), composed of aqueous or nonaqueous dispersions of self-assembled submicron colloidal spheres are emerging toward the development of advanced optical devices for technological applications. This is because of their unique optical diffraction properties and the ease with which these intriguing properties can be modulated experimentally. Moreover our recent advancements in this area which include 'locking' the liquid MPAS into solid or semisolid polymer matrices for greater stability with longer life span, and incorporation of CdS quantum dots and laser dyes into colloidal spheres to obtain nonlinear optical (NLO) responses further corroborate the use of MPAS in optical technology. Our long term goal is fabrication of all-optical and electro-optical devices such as spatial light modulators for optical signal processing and flat panel display devices by utilizing intelligent nonlinear periodic array structural materials. Here we show further progress in the design of novel linear MPAS which have the ability to sense and respond to an external source such as temperature. This is achieved by combining the self-assembly properties of polymer colloidal spheres and thermoshrinking properties of smart polymer gels. At selected temperatures the periodic array efficiently Bragg diffracts light and transmits most of the light at other temperatures. Hence these intelligent systems are of potential use as fixed notch filters optical switches or limiters to protect delicate optical sensors from high intensity laser radiation.
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Interface colloidal robotic manipulator
Aronson, Igor; Snezhko, Oleksiy
2015-08-04
A magnetic colloidal system confined at the interface between two immiscible liquids and energized by an alternating magnetic field dynamically self-assembles into localized asters and arrays of asters. The colloidal system exhibits locomotion and shape change. By controlling a small external magnetic field applied parallel to the interface, structures can capture, transport, and position target particles.
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Electrohydrodynamically patterned colloidal crystals
NASA Technical Reports Server (NTRS)
Hayward, Ryan C. (Inventor); Poon, Hak F. (Inventor); Xiao, Yi (Inventor); Saville, Dudley A. (Inventor); Aksay, Ilhan A. (Inventor)
2003-01-01
A method for assembling patterned crystalline arrays of colloidal particles using ultraviolet illumination of an optically-sensitive semiconducting anode while using the anode to apply an electronic field to the colloidal particles. The ultraviolet illumination increases current density, and consequently, the flow of the colloidal particles. As a result, colloidal particles can be caused to migrate from non-illuminated areas of the anode to illuminated areas of the anode. Selective illumination of the anode can also be used to permanently affix colloidal crystals to illuminated areas of the anode while not affixing them to non-illuminated areas of the anode.
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Continuous separation of colloidal particles using dielectrophoresis.
Yunus, Nurul Amziah Md; Nili, Hossein; Green, Nicolas G
2013-04-01
Dielectrophoresis is the movement of particles in nonuniform electric fields and has been of interest for application to manipulation and separation at and below the microscale. This technique has the advantages of being noninvasive, nondestructive, and noncontact, with the movement of particle achieved by means of electric fields generated by miniaturized electrodes and microfluidic systems. Although the majority of applications have been above the microscale, there is increasing interest in application to colloidal particles around a micron and smaller. This paper begins with a review of colloidal and nanoscale dielectrophoresis with specific attention paid to separation applications. An innovative design of integrated microelectrode array and its application to flow-through, continuous separation of colloidal particles is then presented. The details of the angled chevron microelectrode array and the test microfluidic system are then discussed. The variation in device operation with applied signal voltage is presented and discussed in terms of separation efficiency, demonstrating 99.9% separation of a mixture of colloidal latex spheres. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Ultra-thin layer chromatography with integrated silver colloid-based SERS detection.
Wallace, Ryan A; Lavrik, Nickolay V; Sepaniak, Michael J
2017-01-01
Simplified lab-on-a-chip techniques are desirable for quick and efficient detection of analytes of interest in the field. The following work involves the use of deterministic pillar arrays on the micro-scale as a platform to separate compounds, and the use of Ag colloid within the arrays as a source of increased signal via surface enhanced Raman spectroscopy (SERS). One problem traditionally seen with SERS surfaces containing Ag colloid is oxidation; however, our platforms are superhydrophobic, reducing the amount of oxidation taking place on the surface of the Ag colloid. This work includes the successful separation and SERS detection of a fluorescent dye compounds (resorufin and sulforhodamine 640), fluorescent anti-tumor drugs (Adriamycin and Daunomycin), and purine and pyrimidine bases (adenine, cytosine, guanine, hypoxanthine, and thymine). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Thermally Tunable Hydrogels Displaying Angle-Independent Structural Colors.
Ohtsuka, Yumiko; Seki, Takahiro; Takeoka, Yukikazu
2015-12-14
We report the preparation of thermally tunable hydrogels displaying angle-independent structural colors. The porous structures were formed with short-range order using colloidal amorphous array templates and a small amount of carbon black (CB). The resultant porous hydrogels prepared using colloidal amorphous arrays without CB appeared white, whereas the hydrogels with CB revealed bright structural colors. The brightly colored hydrogels rapidly changed hues in a reversible manner, and the hues varied widely depending on the water temperature. Moreover, the structural colors were angle-independent under diffusive lighting because of the isotropic nanostructure generated from the colloidal amorphous arrays. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
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Surface preparation of substances for continuous convective assembly of fine particles
Rossi, Robert
2003-01-01
A method for producing periodic nanometer-scale arrays of metal or semiconductor junctions on a clean semiconductor substrate surface is provided comprising the steps of: etching the substrate surface to make it hydrophilic, forming, under an inert atmosphere, a crystalline colloid layer on the substrate surface, depositing a metal or semiconductor material through the colloid layer onto the surface of the substrate, and removing the colloid from the substrate surface. The colloid layer is grown on the clean semiconductor surface by withdrawing the semiconductor substrate from a sol of colloid particles.
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Natsume, Yuno; Toyota, Taro
2016-01-01
Giant vesicles (GVs) encapsulating colloidal particles by a specific volume fraction show a characteristic configuration under a hypertonic condition. Several flat faces were formed in GV membrane with orderly array of inner particles. GV shape changed from the spherical to the asymmetrical polyhedral configuration. This shape deformation was derived by entropic interaction between inner particles and GV membrane. Because a part of inner particles became to form an ordered phase in the region neighboring the GV membrane, free volume for the other part of particles increased. Giant vesicles encapsulating colloidal particles were useful for the model of “crowding effect” which is the entropic interaction in the cell. PMID:26752650
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Natsume, Yuno; Toyota, Taro
2016-01-01
Giant vesicles (GVs) encapsulating colloidal particles by a specific volume fraction show a characteristic configuration under a hypertonic condition. Several flat faces were formed in GV membrane with orderly array of inner particles. GV shape changed from the spherical to the asymmetrical polyhedral configuration. This shape deformation was derived by entropic interaction between inner particles and GV membrane. Because a part of inner particles became to form an ordered phase in the region neighboring the GV membrane, free volume for the other part of particles increased. Giant vesicles encapsulating colloidal particles were useful for the model of "crowding effect" which is the entropic interaction in the cell.
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Hu, Yumei; Jiang, Xiaomei; Zhang, Laiying; Fan, Jiao; Wu, Weitai
2013-10-15
Noninvasive monitoring of glucose in tears is highly desirable in tight glucose control. The polymerized crystalline colloidal array (PCCA) that can be incorporated into contact lens represents one of the most promising materials for noninvasive monitoring of glucose in tears. However, low sensitivity and slow time response of the PCCA reported in previous arts has limited its clinical utility. This paper presents a new PCCA, denoted as NIR-PCCA, comprising a CCA of glucose-responsive sub-micrometered poly(styrene-co-acrylamide-co-3-acrylamidophenylboronic acid) microgels embedded within a slightly positive charged hydrogel matrix of poly(acrylamide-co-2-(dimethylamino)ethyl acrylate). This newly designed NIR-PCCA can reflect near-infrared (NIR) light, whose intensity (at 1722 nm) would decrease evidently with increasing glucose concentration over the physiologically relevant range in tears. The lowest glucose concentration reliably detectable was as low as ca. 6.1 μg/dL. The characteristic response time τ(sensing) was 22.1±0.2s when adding glucose to 7.5 mg/dL, and the higher the glucose concentration is, the faster the time response. Such a rationally designed NIR-PCCA is well suited for ratiometric NIR sensing of tear glucose under physiological conditions, thereby likely to bring this promising glucose-sensing material to the forefront of analytical devices for diabetes. Copyright © 2013 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Chen, Cheng; Ding, Taotao; Qi, Zhiqiang; Zhang, Wei; Zhang, Jun; Xu, Juan; Chen, Jingwen; Dai, Jiangnan; Chen, Changqing
2018-04-01
The periodically ordered ZnO nanorod (NR) arrays have been successfully synthesized via a hydrothermal approach on the silicon substrates by templating of the TiO2 ring deriving from the polystyrene (PS) nanosphere monolayer colloidal crystals (MCC). With the inverted MCC mask, sol-gel-derived ZnO seeds could serve as the periodic nucleation positions for the site-specific growth of ZnO NRs. The large-scale patterned arrays of single ZnO NR with good side-orientation can be readily produced. According to the experimental results, the as-integrated ZnO NR arrays showed an excellent crystal quality and optical property, very suitable for optoelectronic applications such as stimulated emitters and ZnO photonic crystal devices.
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NASA Astrophysics Data System (ADS)
Emoto, Akira; Kamei, Tadayoshi; Shioda, Tatsutoshi; Kawatsuki, Nobuhiro; Ono, Hiroshi
2009-06-01
We report the experimental results of two-dimensional patterning of colloidal crystals using edge-patterned cells. Solvent evaporation of a colloidal suspension from the edge of the cell induces self-organized crystallization of spherical colloidal particles. From a reservoir of colloidal suspension in the cell, different colloidal suspensions are injected repetitively. An edge-patterned substrate is introduced into the cell as an upper substrate. As a result, different colloidal crystals are alternately stacked in the lateral direction according to the edge pattern. The characteristics of cloning formation are specifically showed including deformations from the original pattern. This two-dimensional patterning of three-dimensional colloidal crystals by means of lateral autocloning is promising for the development of photonic crystal arrays for use in optic and photonic devices.
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Photoelectrochromism in Tungsten Trioxide Colloidal Solutions
ERIC Educational Resources Information Center
Chenthamarakshan, C. R.; Tacconi, N. R. de; Xu, Lucy; Rajeshwar, Krishnan
2004-01-01
Photophysical and photochemical properties of semiconductor metal oxide colloids are studied in the context of photoelectrochemical conversion and storage of solar energy. The experiment teaches the instrumental principles of UV-visible spectrophotometry, spectral acquisition and background subtraction strategies and diode array spectrometers.
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Polarization Sensitive QWIP Thermal Imager
2000-03-01
array (FPA) with peak responsivity in the long-wave infrared ( LWIR ) spectral band near 9 µm. Polarization-dependent responsivity is achieved by...demonstrated in various combinations: MWIR/ LWIR (using rectangular grid gratings), MWIR/MWIR, and LWIR / LWIR . The FPA described here was fabricated with a...CCA supports the nonuniformity correction, global gain and level control, failed pixel substitution, dynamic range reduction, BIT status and serial
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Brannon, A. Rose; Haake, Scott M.; Hacker, Kathryn E.; Pruthi, Raj S.; Wallen, Eric M.; Nielsen, Matthew E.; Rathmell, W. Kimryn
2011-01-01
Background Clear cell renal cell carcinoma (ccRCC) displays molecular and histologic heterogeneity. Previously described subsets of this disease, ccA and ccB, were defined based on multigene expression profiles, but it is unclear whether these subgroupings reflect the full spectrum of disease or how these molecular subtypes relate to histologic descriptions or gender. Objective Determine whether additional subtypes of ccRCC exist and whether these subtypes are related to von Hippel-Lindau (VHL) inactivation, hypoxia-inducible factor (HIF) 1 and 2 expression, tumor histology, or gender. Design, setting, and participants Six large, publicly available ccRCC gene expression databases were identified that cumulatively provided data for 480 tumors for meta-analysis via meta-array compilation. Measurements Unsupervised consensus clustering was performed on the meta-arrays. Tumors were examined for the relationship of multigene-defined consensus subtypes and expression signatures of VHL mutation and HIF status, tumor histology, and gender. Results and limitations Two dominant subsets of ccRCC were observed. However, a minor third cluster was revealed that correlated strongly with a wild type (WT) VHL expression profile and indications of variant histologies. When variant histologies were removed, ccA tumors naturally divided by gender. This technique is limited by the potential for persistent batch effect, tumor sampling bias, and restrictions of annotated information. Conclusions The ccA and ccB subsets of ccRCC are robust in meta-analysis among histologically conventional ccRCC tumors. A third group of tumors was identified that may represent a new variant of ccRCC. Within definitively clear cell tumors, gender may delineate tumors in such a way that it could have implications regarding current treatments and future drug development. PMID:22030119
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Fan, Wen; Chen, Min; Yang, Shu; Wu, Limin
2015-01-01
Self-assembly of colloidal particles into colloidal films has many actual and potential applications. While various strategies have been developed to direct the assembly of colloidal particles, fabrication of crack-free and transferrable colloidal film with controllable crystal structures still remains a major challenge. Here we show a centrifugation-assisted assembly of colloidal silica spheres into free-standing colloidal film by using the liquid/liquid interfaces of three immiscible phases. Through independent control of centrifugal force and interparticle electrostatic repulsion, polycrystalline, single-crystalline and quasi-amorphous structures can be readily obtained. More importantly, by dehydration of silica particles during centrifugation, the spontaneous formation of capillary water bridges between particles enables the binding and pre-shrinkage of the assembled array at the fluid interface. Thus the assembled colloidal films are not only crack-free, but also robust and flexible enough to be easily transferred on various planar and curved substrates. PMID:26159121
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Colloidal transport through trap arrays controlled by active microswimmers
NASA Astrophysics Data System (ADS)
Yang, Wen; Misko, Vyacheslav R.; Marchesoni, Fabio; Nori, Franco
2018-07-01
We investigate the dynamics of a binary mixture consisting of active and passive colloidal particles diffusing in a 2D array of truncated harmonic wells, or traps. We explore the possibility of using a small fraction of active particles to manipulate a much larger fraction of passive particles, for instance, to confine them in or extract them from the traps. The results of our study have potential application in biology and medical sciences, for example, to remove dead cells or undesired contaminants from biological systems by means of self-propelled nano-robots.
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Collective mechanical behavior of multilayer colloidal arrays of hollow nanoparticles.
Yin, Jie; Retsch, Markus; Thomas, Edwin L; Boyce, Mary C
2012-04-03
The collective mechanical behavior of multilayer colloidal arrays of hollow silica nanoparticles (HSNP) is explored under spherical nanoindentation through a combination of experimental, numerical, and theoretical approaches. The effective indentation modulus E(ind) is found to decrease with an increasing number of layers in a nonlinear manner. The indentation force versus penetration depth behavior for multilayer hollow particle arrays is predicted by an approximate analytical model based on the spring stiffness of the individual particles and the multipoint, multiparticle interactions as well as force transmission between the layers. The model is in good agreement with experiments and with detailed finite element simulations. The ability to tune the effective indentation modulus, E(ind), of the multilayer arrays by manipulating particle geometry and layering is revealed through the model, where E(ind) = (0.725m(-3/2) + 0.275)E(mon) and E(mon) is the monolayer modulus and m is number of layers. E(ind) is seen to plateau with increasing m to E(ind_plateau) = 0.275E(mon) and E(mon) scales with (t/R)(2), t being the particle shell thickness and R being the particle radius. The scaling law governing the nonlinear decrease in indentation modulus with an increase in layer number (E(ind) scaling with m(-3/2)) is found to be similar to that governing the indentation modulus of thin solid films E(ind_solid) on a stiff substrate (where E(ind_solid) scales with h(-1.4) and also decreases until reaching a plateau value) which also decreases with an increase in film thickness h. However, the mechanisms underlying this trend for the colloidal array are clearly different, where discrete particle-to-particle interactions govern the colloidal array behavior in contrast to the substrate constraint on deformation, which governs the thickness dependence of the continuous thin film indentation modulus.
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Arrays of size and distance controlled platinum nanoparticles fabricated by a colloidal method
NASA Astrophysics Data System (ADS)
Manzke, Achim; Vogel, Nicolas; Weiss, Clemens K.; Ziener, Ulrich; Plettl, Alfred; Landfester, Katharina; Ziemann, Paul
2011-06-01
Based on emulsion polymerization in the presence of a Pt complex, polystyrene (PS) particles were prepared exhibiting a well defined average diameter with narrow size-distribution. Furthermore, the colloids contain a controlled concentration of the Pt precursor complex. Optimized coating of Si substrates with such colloids leads to extended areas of hexagonally ordered close-packed PS particles. Subsequent application of plasma etching and annealing steps allows complete removal of the PS carriers and in parallel nucleation and growth of Pt nanoparticles (NPs) which are located at the original center of the PS colloids. In this way, hexagonally arranged spherical Pt NPs are obtained with controlled size and interparticle distances demonstrating variability and precision with so far unknown parameter scalability. This control is demonstrated by the fabrication of Pt NP arrays at a fixed particle distance of 185 nm while systematically varying the diameters between 8 and 15 nm. Further progress could be achieved by seeded emulsion polymerization. Here, Pt loaded PS colloids of 130 nm were used as seeds for a subsequent additional emulsion polymerization, systematically enlarging the diameter of the PS particles. Applying the plasma and annealing steps as above, in this way hexagonally ordered arrays of 9 nm Pt NPs could be obtained at distances up to 260 nm. To demonstrate their stability, such Pt particles were used as etching masks during reactive ion etching thereby transferring their hexagonal pattern into the Si substrate resulting in corresponding arrays of nanopillars.Based on emulsion polymerization in the presence of a Pt complex, polystyrene (PS) particles were prepared exhibiting a well defined average diameter with narrow size-distribution. Furthermore, the colloids contain a controlled concentration of the Pt precursor complex. Optimized coating of Si substrates with such colloids leads to extended areas of hexagonally ordered close-packed PS particles. Subsequent application of plasma etching and annealing steps allows complete removal of the PS carriers and in parallel nucleation and growth of Pt nanoparticles (NPs) which are located at the original center of the PS colloids. In this way, hexagonally arranged spherical Pt NPs are obtained with controlled size and interparticle distances demonstrating variability and precision with so far unknown parameter scalability. This control is demonstrated by the fabrication of Pt NP arrays at a fixed particle distance of 185 nm while systematically varying the diameters between 8 and 15 nm. Further progress could be achieved by seeded emulsion polymerization. Here, Pt loaded PS colloids of 130 nm were used as seeds for a subsequent additional emulsion polymerization, systematically enlarging the diameter of the PS particles. Applying the plasma and annealing steps as above, in this way hexagonally ordered arrays of 9 nm Pt NPs could be obtained at distances up to 260 nm. To demonstrate their stability, such Pt particles were used as etching masks during reactive ion etching thereby transferring their hexagonal pattern into the Si substrate resulting in corresponding arrays of nanopillars. Electronic supplementary information (ESI) available: Detailed description of the experimental part (S1-S4) platinum concentration inside the polymer particles synthesized by a seeded polymerization from the same seed particles measured by ICP-OES (Fig. S1 and S5); SEM image of Pt complex containing PS particles after oxygen plasma treatment (Fig. S2 and S6); effect of hydrofluoric acid treatment on silicon oxide elevation under Pt NPs (Fig. S3 and S6); SEM images demonstrating the variability of Pt NP distance while keeping the diameter constant (Fig. S4 and S8); results of experimental determination of Pt content by ICP-OES (Tables S1 and S9); diameter of the particles at different fabrication states (Tables S2 and S10). See DOI: 10.1039/c1nr10169b
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NASA Astrophysics Data System (ADS)
Burtsev, Vasilii; Marchuk, Valentina; Kugaevskiy, Artem; Guselnikova, Olga; Elashnikov, Roman; Miliutina, Elena; Postnikov, Pavel; Svorcik, Vaclav; Lyutakov, Oleksiy
2018-03-01
Nano-spheres lithography is actually considered as a powerful tool to manufacture various periodic structures with a wide potential in the field of nano- and micro-fabrication. However, during self-assembling of colloid microspheres, various defects and mismatches can appear. In this work the size and quality of single-domains of closed-packed polystyrene (PS), grown up on thin Au layers modified by hydrophilic or hydrophobic functional groups via diazonium chemistry was studied. The effects of the surface modification on the quality and single-domain size of polystyrene (PS) microspheres array were investigated and discussed. Modified surfaces were characterized using the AFM and wettability tests. PS colloidal suspension was deposited using the drop evaporation method. Resulted PS microspheres array was characterized using the SEM, AFM and confocal microscopy technique.
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Swaminathan, Vikhram V; Shannon, Mark A; Bashir, Rashid
2015-04-01
Dielectrophoretic separation of particles finds a variety of applications in the capture of species such as cells, viruses, proteins, DNA from biological systems, as well as other organic and inorganic contaminants from water. The ability to capture particles is constrained by poor volumetric scaling of separation force with respect to particle diameter, as well as the weak penetration of electric fields in the media. In order to improve the separation of sub-micron colloids, we present a scheme based on multiple interdigitated electrode arrays under mixed AC/DC bias. The use of high frequency longitudinal AC bias breaks the shielding effects through electroosmotic micromixing to enhance electric fields through the electrolyte, while a transverse DC bias between the electrode arrays enables penetration of the separation force to capture particles from the bulk of the microchannel. We determine the favorable biasing conditions for field enhancement with the help of analytical models, and experimentally demonstrate the improved capture from sub-micron colloidal suspensions with the mixed AC/DC electrostatic excitation scheme over conventional AC-DEP methods.
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Nakanuma, Yasuni; Sato, Yasunori
2014-07-01
Routine experiences suggest that cholangiocarcinomas (CCAs) show different clinicopathological behaviors along the biliary tree, and hilar CCA apparently resembles pancreatic duct adenocarcinoma (PDAC). Herein, the backgrounds for these similarities were reviewed. While all cases of PDAC, hilar CCA, intrahepatic CCA (ICCA) and CCA components of combined hepatocellular-cholangiocarcinoma (cHC-CCA) were adenocarcinomas, micropapillary patterns and columnar carcinoma cells were common in PDAC and hilar CCA, and trabecular components and cuboidal carcinoma cells were common in ICCA and CCA components of cHC-CCA. Anterior gradient protein-2 and S100P were frequently expressed in perihilar CCA and PDAC, while neural cell adhesion molecule and luminal epithelial membrane antigen were common in CCA components of c-HC-CCA. Pdx1 and Hes1 were frequently and markedly expressed aberrantly in PDAC and perihilar CCA, although their expression was rare and mild in CCA components in cHC-CCA and ICCA. Hilar CCA showed a similar postoperative prognosis to PDAC but differed from ICCA and cHC-CCA. Taken together, hilar CCA may differ from ICCA and CCA components of cHC-CCA but have a similar development to PDAC. These similarities may be explained by the unique anatomical, embryological and reactive nature of the pancreatobiliary tract. Further studies of these intractable malignancies are warranted. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.
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Alvaro, Domenico; Bragazzi, Maria Consiglia; Benedetti, Antonio; Fabris, Luca; Fava, Giammarco; Invernizzi, Pietro; Marzioni, Marco; Nuzzo, Gennaro; Strazzabosco, Mario; Stroffolini, Tommaso
2011-01-01
Very few studies assessed cholangiocarcinoma clinical characteristics. To evaluate the clinical characteristics of intra-hepatic (IH) and extra-hepatic (EH)-CCA. We performed a national survey based on a questionnaire. 218 cholangiocarcinomas were observed (47% EH-CCA, 53% IH-CCA) with an age at the diagnosis higher for EH-CCA. Coexistence of cirrhosis or viral cirrhosis was more frequent in IH-CCA than EH-CCA. An incidental asymptomatic presentation occurred in 28% of IH-CCA vs 4% EH-CCA whilst, 74% EH-CCA vs 28% IH-CCA presented with jaundice. 91% of IH-CCA presented as a single intra-hepatic mass, whilst 50% of EH-CCA was peri-hilar. In the diagnostic work-up, 70% of all cholangiocarcinoma cases received at least 3 different imaging procedures. Tissue-proven diagnosis was obtained in 80% cholangiocarcinoma. Open surgery with curative intent was performed in 45% of IH-CCA and 29% EH-CCA. 18% IH-CCA vs 4% EH-CCA did not received treatment. In Italy IH-CCA is managed as frequently as EH-CCA. In comparison to EH-CCA, IH-CCA occurs at younger age and is more frequently associated with cirrhosis and with an incidental asymptomatic presentation. In contrast, most EH-CCAs are jaundiced at the diagnosis. Cholangiocarcinoma diagnostic management is cost- and time-consuming with curative surgical treatment applicable more frequently in IH-CCA. Copyright © 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
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Mid-IR colloidal quantum dot detectors enhanced by optical nano-antennas
NASA Astrophysics Data System (ADS)
Yifat, Yuval; Ackerman, Matthew; Guyot-Sionnest, Philippe
2017-01-01
We report the fabrication of a colloidal quantum dot based photodetector designed for the 3-5 μm mid infrared wavelength range incorporated with optical nano-antenna arrays to enhance the photocurrent. The fabricated arrays exhibit a resonant behavior dependent on the length of the nano-antenna rods, in good agreement with numerical simulation. The device exhibits a three-fold increase in the spectral photoresponse compared to a photodetector device without antennas, and the resonance is polarized parallel to the antenna orientation. We numerically estimate the device quantum efficiency and investigate its bias dependence.
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Bacteriophage PRD1 and silica colloid transport and recovery in an iron oxide-coated sand aquifer
Ryan, J.N.; Elimelech, M.; Ard, R.A.; Harvey, R.W.; Johnson, P.R.
1999-01-01
Bacteriophage PRD1 and silica colloids were co-injected into sewage- contaminated and uncontaminated zones of an iron oxide-coated sand aquifer on Cape Cod, MA, and their transport was monitored over distances up to 6 m in three arrays. After deposition, the attached PRD1 and silica colloids were mobilized by three different chemical perturbations (elevated pH, anionic surfactant, and reductant). PRD1 and silica colloids experienced less attenuation in the contaminated zone where adsorbed organic matter and phosphate may be hindering attachment of PRD1 and silica colloids to the iron oxide coatings. The PRD1 collision efficiencies agree well with collision efficiencies predicted by assuming favorable PRD1 deposition on iron oxide coatings for which the surface area coverage was measured by microprobe analysis of sediment thin sections. ?? potentials of the PRD1, silica colloids, and aquifer grains corroborated the transport results, indicating that electrostatic forces dominated the attachment of PRD1 and silica colloids. Elevated pH was the chemical perturbation most effective at mobilizing the attached PRD1 and silica colloids. Elevated surfactant concentration mobilized the attached PRD1 and silica colloids more effectively in the contaminated zone than in the uncontaminated zone.Bacteriophage PRD1 and silica colloids were co-injected into sewage-contaminated and uncontaminated zones of an iron oxide-coated sand aquifer on Cape Cod, MA, and their transport was monitored over distances up to 6 m in three arrays. After deposition, the attached PRD1 and silica colloids were mobilized by three different chemical perturbations (elevated pH, anionic surfactant, and reductant). PRD1 and silica colloids experienced less attenuation in the contaminated zone where adsorbed organic matter and phosphate may be hindering attachment of PRD1 and silica colloids to the iron oxide coatings. The PRD1 collision efficiencies agree well with collision efficiencies predicted by assuming favorable PRD1 deposition on iron oxide coatings for which the surface area coverage was measured by microprobe analysis of sediment thin sections. ?? potentials of the PRD1, silica colloids, and aquifer grains corroborated the transport results, indicating that electrostatic forces dominated the attachment of PRD1 and silica colloids. Elevated pH was the chemical perturbation most effective at mobilizing the attached PRD1 and silica colloids. Elevated surfactant concentration mobilized the attached PRD1 and silica colloids more effectively in the contaminated zone than in the uncontaminated zone.
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NASA Astrophysics Data System (ADS)
Murphy, Graham P.; Gough, John J.; Higgins, Luke J.; Karanikolas, Vasilios D.; Wilson, Keith M.; Garcia Coindreau, Jorge A.; Zubialevich, Vitaly Z.; Parbrook, Peter J.; Bradley, A. Louise
2017-03-01
Non-radiative energy transfer (NRET) can be an efficient process of benefit to many applications including photovoltaics, sensors, light emitting diodes and photodetectors. Combining the remarkable optical properties of quantum dots (QDs) with the electrical properties of quantum wells (QWs) allows for the formation of hybrid devices which can utilize NRET as a means of transferring absorbed optical energy from the QDs to the QW. Here we report on plasmon-enhanced NRET from semiconductor nanocrystal QDs to a QW. Ag nanoparticles in the form of colloids and ordered arrays are used to demonstrate plasmon-mediated NRET from QDs to QWs with varying top barrier thicknesses. Plasmon-mediated energy transfer (ET) efficiencies of up to ˜25% are observed with the Ag colloids. The distance dependence of the plasmon-mediated ET is found to follow the same d -4 dependence as the direct QD to QW ET. There is also evidence for an increase in the characteristic distance of the interaction, thus indicating that it follows a Förster-like model with the Ag nanoparticle-QD acting as an enhanced donor dipole. Ordered Ag nanoparticle arrays display plasmon-mediated ET efficiencies up to ˜21%. To explore the tunability of the array system, two arrays with different geometries are presented. It is demonstrated that changing the geometry of the array allows a transition from overall quenching of the acceptor QW emission to enhancement, as well as control of the competition between the QD donor quenching and ET rates.
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Lateral separation of colloids or cells by dielectrophoresis augmented by AC electroosmosis.
Zhou, Hao; White, Lee R; Tilton, Robert D
2005-05-01
Colloidal particles and biological cells are patterned and separated laterally adjacent to a micropatterned electrode array by applying AC electric fields that are principally oriented normally to the electrode array. This is demonstrated for yeast cells, red blood cells, and colloidal polystyrene particles of different sizes and zeta-potentials. The separation mechanism is observed experimentally to depend on the applied field frequency and voltage. At high frequencies, particles position themselves in a manner that is consistent with dielectrophoresis, while at low frequencies, the positioning is explained in terms of a strong coupling between gravity, the vertical component of the dielectrophoretic force, and the Stokes drag on particles induced by AC electroosmotic flow. Compared to high frequency dielectrophoretic separations, the low frequency separations are faster and require lower applied voltages. Furthermore, the AC electroosmosis coupling with dielectrophoresis may enable cell separations that are not feasible based on dielectrophoresis alone.
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Bacteriophage PRD1 and silica colloids were co-injected into
sewage-contaminated and uncontaminated zones of an iron oxide-coated sand
aquifer on Cape Cod, MA, and their transport was monitored over distances up to
6 m in three arrays. After deposition, the attache... -
Dynamic Colloidal Molecules Maneuvered by Light-Controlled Janus Micromotors.
Gao, Yirong; Mou, Fangzhi; Feng, Yizheng; Che, Shengping; Li, Wei; Xu, Leilei; Guan, Jianguo
2017-07-12
In this work, we propose and demonstrate a dynamic colloidal molecule that is capable of moving autonomously and performing swift, reversible, and in-place assembly dissociation in a high accuracy by manipulating a TiO 2 /Pt Janus micromotor with light irradiation. Due to the efficient motion of the TiO 2 /Pt Janus motor and the light-switchable electrostatic interactions between the micromotor and colloidal particles, the colloidal particles can be captured and assembled one by one on the fly, subsequently forming into swimming colloidal molecules by mimicking space-filling models of simple molecules with central atoms. The as-demonstrated dynamic colloidal molecules have a configuration accurately controlled and stabilized by regulating the time-dependent intensity of UV light, which controls the stop-and-go motion of the colloidal molecules. The dynamic colloidal molecules are dissociated when the light irradiation is turned off due to the disappearance of light-switchable electrostatic interaction between the motor and the colloidal particles. The strategy for the assembly of dynamic colloidal molecules is applicable to various charged colloidal particles. The simulated optical properties of a dynamic colloidal molecule imply that the results here may provide a novel approach for in-place building functional microdevices, such as microlens arrays, in a swift and reversible manner.
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Monolayer Colloidal Crystals by Modified Air-Water Interface Self-Assembly Approach
Ye, Xin; Huang, Jin; Zeng, Yong; Sun, Lai-Xi; Geng, Feng; Liu, Hong-Jie; Wang, Feng-Rui; Jiang, Xiao-Dong; Wu, Wei-Dong; Zheng, Wan-Guo
2017-01-01
Hexagonally ordered arrays of polystyrene (PS) microspheres were prepared by a modified air-water self-assembly method. A detailed analysis of the air-water interface self-assembly process was conducted. Several parameters affect the quality of the monolayer colloidal crystals, i.e., the colloidal microsphere concentration on the latex, the surfactant concentration, the polystyrene microsphere diameter, the microsphere polydispersity, and the degree of sphericity of polystyrene microspheres. An abrupt change in surface tension was used to improve the quality of the monolayer colloidal crystal. Three typical microstructures, i.e., a cone, a pillar, and a binary structure were prepared by reactive-ion etching using a high-quality colloidal crystal mask. This study provides insight into the production of microsphere templates with flexible structures for large-area patterned materials. PMID:28946664
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Bui, Minh-Phuong N; Seo, Seong S
2014-01-01
We have developed an optical chemical sensor for the detection of organophosphate (OP) compounds using a polymerized crystalline colloidal array (PCCA) thin film composed of a close-packed colloidal array of polystyrene particles. The PCCA thin film was modified with β-cyclodextrin (β-CD) polymer as a capping cavity for the selective detection of paraoxon-ethyl and parathion-ethyl chemical agents. The fabrication of the modified PCCA thin film was optimized and the structure was characterized using scanning electron microscopy (SEM). The arrangement of polystyrene particles in the PCCA follows a pattern of the fcc (111) planes with strong diffraction peak in the visible spectral region and pH dependence. The diffraction peak of the β-CD modified PCCA thin film showed a red shift according to the change of paraoxon-ethyl and parathion-ethyl concentrations at a fast response time (10 s) and high sensitivity with detection limits of 2.0 and 3.4 ppb, respectively. Furthermore, the proposed interaction mechanism of β-CD with paraoxon-ethyl and parathion-ethyl in the β-CD modified PCCA thin film were discussed.
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Statistical interpretation of transient current power-law decay in colloidal quantum dot arrays
NASA Astrophysics Data System (ADS)
Sibatov, R. T.
2011-08-01
A new statistical model of the charge transport in colloidal quantum dot arrays is proposed. It takes into account Coulomb blockade forbidding multiple occupancy of nanocrystals and the influence of energetic disorder of interdot space. The model explains power-law current transients and the presence of the memory effect. The fractional differential analogue of the Ohm law is found phenomenologically for nanocrystal arrays. The model combines ideas that were considered as conflicting by other authors: the Scher-Montroll idea about the power-law distribution of waiting times in localized states for disordered semiconductors is applied taking into account Coulomb blockade; Novikov's condition about the asymptotic power-law distribution of time intervals between successful current pulses in conduction channels is fulfilled; and the carrier injection blocking predicted by Ginger and Greenham (2000 J. Appl. Phys. 87 1361) takes place.
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Adipocytes promote cholangiocarcinoma metastasis through fatty acid binding protein 4.
Nie, Jihua; Zhang, Jingying; Wang, Lili; Lu, Lunjie; Yuan, Qian; An, Fangmei; Zhang, Shuyu; Jiao, Yang
2017-12-13
The early occurrence regional nodal and distant metastases cholangiocarcinoma (CCA) is one of the major reasons for its poor prognosis. However, the related mechanisms are largely elusive. Recently, increasing evidences indicate that adipocytes might be involved in the proliferation, homing, migration and invasion of several malignancies. In the present study, we attempt to determine the effects and possible mechanisms of adipocytes on regulating progression of CCA. Adipocyte-CCA cell co-culture system and CCA metastasis mice model were used to determine the effects of adipocytes on CCA metastasis. We identified the biological functions and possible mechanisms of adipocyte-derived fatty acid binding protein 4 (FABP4) in regulating the adipocyte-induced CCA metastasis and epithelial-mesenchymal transition (EMT) phenotypes, both in vitro and in vivo. Adipocyte-CCA cell co-culture promotes the in vitro and in vivo tumor metastasis, leading to increased adipocyte-derived fatty acid absorbance and intracellular lipids of CCA cells, which indicates adipocytes might function as the energy source for CCA progression by providing free fatty acids. Further, highly expressed FABP4 protein was identified in adipose tissues and fully differentiated adipocytes, and upregulated FABP4 was also detected by qRT-PCR assay in CCA cells co-cultivated with adipose extracts as compared to parental CCA cells. The specific FABP4 inhibitor BMS309403 significantly impaired adipocyte-induced CCA metastasis and EMT phenotypes both in vitro and in vivo. Together, the results demonstrate that the adipocyte-CCA interaction and the energy extraction of CCA cells from adipocytes are crucial for the invasion, migration and EMT of CCA cells. FABP4 from adipocytes mediates these adipocyte-induced variations in CCA cells, which could serve as a potential target for the treatment of CCA.
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Two-color beam improvement of the colloidal particle lens array assisted surface nanostructuring
NASA Astrophysics Data System (ADS)
Afanasiev, Andrei; Bredikhin, Vladimir; Pikulin, Alexander; Ilyakov, Igor; Shishkin, Boris; Akhmedzhanov, Rinat; Bityurin, Nikita
2015-05-01
We consider laser nanostructuring of the material surface by means of a colloidal particle lens array. Here, the monolayer of dielectric micro- or nanospheres placed on the surface acts as an array of near-field lenses that focus the laser radiation into the multitude of distinct spots, allowing the formation of many structures in a single stage. We show that conversion of a small part of the energy of the femtosecond beam into the second harmonic (SH) is an efficient way to increase the surface density of obtained nanostructures. By combining the fundamental frequency and the SH, one benefits both from the power of the former and from the focusing ability of the latter. This combination provides an efficient nanostructuring with sphere diameter close to the wavelength of the second harmonic. The possibility to create arrays of nanostructures with surface density above 5 × 10 8 cm - 2 with femtosecond Ti:sapphire laser operating at 800 nm was demonstrated by employing 0.45 μm spheres.
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Cheng, S L; Wong, S L; Lu, S W; Chen, H
2008-09-01
We report here the successful fabrication of large-area size-tunable periodic arrays of cobalt and Co-silicide nanodots on silicon substrates by employing the colloidal nanosphere lithography (NSL) technique and heat treatments. The growth of low-resistivity epitaxial CoSi(2) was found to be more favorable for the samples with smaller Co nanodot sizes. The sizes of the epitaxial CoSi(2) nanodots can be tuned from 50 to 100 nm by varying the diameter of the colloidal spheres and annealing temperatures. The epitaxial CoSi(2) nanodots were found to grow with an epitaxial orientation with respect to the (001)Si substrates: [001]CoSi(2)//[001]Si and (200)CoSi(2)//(400)Si. From the results of planview HRTEM, XTEM, and SAED analysis, the epitaxial CoSi(2) nanodots were identified to be inverse pyramids in shape, and the average sizes of the faceted silicide nanodots were measured to decrease with annealing temperature. The observed results present the exciting prospect that with appropriate controls, the colloidal NSL technique promises to facilitate the growth of a variety of well-ordered silicide nanodots with selected shape, size, and periodicity.
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Zhang, Aying; Jiang, Mingyi
2012-01-01
Nitric oxide (NO), hydrogen peroxide (H2O2), and calcium (Ca2+)/calmodulin (CaM) are all required for abscisic acid (ABA)-induced antioxidant defence. Ca2+/CaM-dependent protein kinase (CCaMK) is a strong candidate for the decoder of Ca2+ signals. However, whether CCaMK is involved in ABA-induced antioxidant defence is unknown. The results of the present study show that exogenous and endogenous ABA induced increases in the activity of ZmCCaMK and the expression of ZmCCaMK in leaves of maize. Subcellular localization analysis showed that ZmCCaMK is located in the nucleus, the cytoplasm, and the plasma membrane. The transient expression of ZmCCaMK and the RNA interference (RNAi) silencing of ZmCCaMK analysis in maize protoplasts revealed that ZmCCaMK is required for ABA-induced antioxidant defence. Moreover, treatment with the NO donor sodium nitroprusside (SNP) induced the activation of ZmCCaMK and the expression of ZmCCaMK. Pre-treatments with an NO scavenger and inhibitor blocked the ABA-induced increases in the activity and the transcript level of ZmCCaMK. Conversely, RNAi silencing of ZmCCaMK in maize protoplasts did not affect the ABA-induced NO production, which was further confirmed using a mutant of OsCCaMK, the homologous gene of ZmCCaMK in rice. Moreover, H2O2 was also required for the ABA activation of ZmCCaMK, and pre-treatments with an NO scavenger and inhibitor inhibited the H2O2-induced increase in the activity of ZmCCaMK. Taken together, the data clearly suggest that ZmCCaMK is required for ABA-induced antioxidant defence, and H2O2-dependent NO production plays an important role in the ABA-induced activation of ZmCCaMK. PMID:22865912
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Emerging molecular therapeutic targets for cholangiocarcinoma.
Rizvi, Sumera; Gores, Gregory J
2017-09-01
Cholangiocarcinomas (CCAs) are diverse epithelial tumors arising from the liver or large bile ducts with features of cholangiocyte differentiation. CCAs are classified anatomically into intrahepatic (iCCA), perihilar (pCCA), and distal CCA (dCCA). Each subtype has distinct risk factors, molecular pathogenesis, therapeutic options, and prognosis. CCA is an aggressive malignancy with a poor overall prognosis and median survival of less than 2years in patients with advanced disease. Potentially curative surgical treatment options are limited to the subset of patients with early-stage disease. Presently, the available systemic medical therapies for advanced or metastatic CCA have limited therapeutic efficacy. Molecular alterations define the differences in biological behavior of each CCA subtype. Recent comprehensive genetic analysis has better characterized the genomic and transcriptomic landscape of each CCA subtype. Promising candidates for targeted, personalized therapy have emerged, including potential driver fibroblast growth factor receptor (FGFR) gene fusions and somatic mutations in isocitrate dehydrogenase (IDH)1/2 in iCCA, protein kinase cAMP-activated catalytic subunit alpha (PRKACA) or beta (PRKACB) gene fusions in pCCA, and ELF3 mutations in dCCA/ampullary carcinoma. A precision genomic medicine approach is dependent on an enhanced understanding of driver mutations in each subtype and stratification of patients according to their genetic drivers. We review the current genomic landscape of CCA, the potentially actionable molecular aberrations in each CCA subtype, and the role of immunotherapy in CCA. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
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Nguyen, Mai; Kanaev, Andrei; Sun, Xiaonan; Lacaze, Emmanuelle; Lau-Truong, Stéphanie; Lamouri, Aazdine; Aubard, Jean; Felidj, Nordin; Mangeney, Claire
2015-11-24
A smart and highly SERS-active plasmonic platform was designed by coupling regular arrays of nanotriangles to colloidal gold nanorods via a thermoresponsive polymer spacer (poly(N-isopropylacrylamide), PNIPAM). The substrates were prepared by combining a top-down and a bottom-up approach based on nanosphere lithography, surface-initiated controlled radical polymerization, and colloidal assembly. This multistep strategy provided regular hexagonal arrays of nanotriangles functionalized by polymer brushes and colloidal gold nanorods, confined exclusively on the nanotriangle surface. Interestingly, one could finely tune the gold nanorod impregnation on the polymer-coated nanostructures by adjusting the polymer layer thickness, leading to highly coupled plasmonic systems for intense SERS signal. Moreover, the thermoresponsive properties of the PNIPAM brushes could be wisely handled in order to monitor the SERS activity of the nanostructures coupled via this polymer spacer. The coupled hybrid plasmonic nanostructures designed in this work are therefore very promising smart platforms for the sensitive detection of analytes by SERS.
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LWD-TCP complex activates the morning gene CCA1 in Arabidopsis.
Wu, Jing-Fen; Tsai, Huang-Lung; Joanito, Ignasius; Wu, Yi-Chen; Chang, Chin-Wen; Li, Yi-Hang; Wang, Ying; Hong, Jong Chan; Chu, Jhih-Wei; Hsu, Chao-Ping; Wu, Shu-Hsing
2016-10-13
A double-negative feedback loop formed by the morning genes CIRCADIAN CLOCK ASSOCIATED1 (CCA1)/LATE ELONGATED HYPOCOTYL (LHY) and the evening gene TIMING OF CAB EXPRESSION1 (TOC1) contributes to regulation of the circadian clock in Arabidopsis. A 24-h circadian cycle starts with the peak expression of CCA1 at dawn. Although CCA1 is targeted by multiple transcriptional repressors, including PSEUDO-RESPONSE REGULATOR9 (PRR9), PRR7, PRR5 and CCA1 HIKING EXPEDITION (CHE), activators of CCA1 remain elusive. Here we use mathematical modelling to infer a co-activator role for LIGHT-REGULATED WD1 (LWD1) in CCA1 expression. We show that the TEOSINTE BRANCHED 1-CYCLOIDEA-PCF20 (TCP20) and TCP22 proteins act as LWD-interacting transcriptional activators. The concomitant binding of LWD1 and TCP20/TCP22 to the TCP-binding site in the CCA1 promoter activates CCA1. Our study reveals activators of the morning gene CCA1 and provides an action mechanism that ensures elevated expression of CCA1 at dawn to sustain a robust clock.
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LWD–TCP complex activates the morning gene CCA1 in Arabidopsis
Wu, Jing-Fen; Tsai, Huang-Lung; Joanito, Ignasius; Wu, Yi-Chen; Chang, Chin-Wen; Li, Yi-Hang; Wang, Ying; Hong, Jong Chan; Chu, Jhih-Wei; Hsu, Chao-Ping; Wu, Shu-Hsing
2016-01-01
A double-negative feedback loop formed by the morning genes CIRCADIAN CLOCK ASSOCIATED1 (CCA1)/LATE ELONGATED HYPOCOTYL (LHY) and the evening gene TIMING OF CAB EXPRESSION1 (TOC1) contributes to regulation of the circadian clock in Arabidopsis. A 24-h circadian cycle starts with the peak expression of CCA1 at dawn. Although CCA1 is targeted by multiple transcriptional repressors, including PSEUDO-RESPONSE REGULATOR9 (PRR9), PRR7, PRR5 and CCA1 HIKING EXPEDITION (CHE), activators of CCA1 remain elusive. Here we use mathematical modelling to infer a co-activator role for LIGHT-REGULATED WD1 (LWD1) in CCA1 expression. We show that the TEOSINTE BRANCHED 1-CYCLOIDEA-PCF20 (TCP20) and TCP22 proteins act as LWD-interacting transcriptional activators. The concomitant binding of LWD1 and TCP20/TCP22 to the TCP-binding site in the CCA1 promoter activates CCA1. Our study reveals activators of the morning gene CCA1 and provides an action mechanism that ensures elevated expression of CCA1 at dawn to sustain a robust clock. PMID:27734958
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Periodic assembly of nanoparticle arrays in disclinations of cholesteric liquid crystals.
Li, Yunfeng; Prince, Elisabeth; Cho, Sangho; Salari, Alinaghi; Mosaddeghian Golestani, Youssef; Lavrentovich, Oleg D; Kumacheva, Eugenia
2017-02-28
An important goal of the modern soft matter science is to discover new self-assembly modalities to precisely control the placement of small particles in space. Spatial inhomogeneity of liquid crystals offers the capability to organize colloids in certain regions such as the cores of the topological defects. Here we report two self-assembly modes of nanoparticles in linear defects-disclinations in a lyotropic colloidal cholesteric liquid crystal: a continuous helicoidal thread and a periodic array of discrete beads. The beads form one-dimensional arrays with a periodicity that matches half a pitch of the cholesteric phase. The periodic assembly is governed by the anisotropic surface tension and elasticity at the interface of beads with the liquid crystal. This mode of self-assembly of nanoparticles in disclinations expands our ability to use topological defects in liquid crystals as templates for the organization of nanocolloids.
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Hui Pan; Chung-Yun Hse; Robert Gambrell; Todd F. Shupe
2009-01-01
Chromated copper arsenate (CCA)-treated wood was liquefied with polyethylene glycol/glycerin and sulfuric acid. After liquefaction, most CCA metals (98% As, 92% Cr, and 83% Cu) were removed from liquefied CCA-treated wood by precipitation with calcium hydroxide. The original CCA-treated wood and liquefied CCA-treated wood sludge were fractionated by a modified...
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Approved Methods and Algorithms for DoD Risk-Based Explosives Siting
2009-07-21
Parameter used in determining probability of hit ( Phit ) by debris. [Table 31, Table 32, Table 33, Eq. (157), Eq. (158)] CCa Variable “Actual...being in the glass hazard area”. [Eq. (60), Eq. (78)] Phit Variable “Probability of hit”. An array value indexed by consequence and mass bin...Eq. (156), Eq. (157)] Phit (f) Variable “Probability of hit for fatality”. [Eq. (157), Eq. (158)] Phit (maji) Variable “Probability of hit for major
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Evaporative lithographic patterning of binary colloidal films.
Harris, Daniel J; Conrad, Jacinta C; Lewis, Jennifer A
2009-12-28
Evaporative lithography offers a promising new route for patterning a broad array of soft materials. In this approach, a mask is placed above a drying film to create regions of free and hindered evaporation, which drive fluid convection and entrained particles to regions of highest evaporative flux. We show that binary colloidal films exhibit remarkable pattern formation when subjected to a periodic evaporative landscape during drying.
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Colloidal-gold electrosensor measuring device
Wegner, S.; Harpold, M.A.; McCaffrey, T.M.; Morris, S.E.; Wojciechowski, M.; Zhao, J.; Henkens, R.W.; Naser, N.; O`Daly, J.P.
1995-11-21
The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 {micro}g/dL in blood samples as small as 10 {micro}L. 9 figs.
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Avalanches and plasticity for colloids in a time dependent optical trap
Olson Reichhardt, Cynthia Jane; McDermott, Danielle Marie; Reichhardt, Charles
2015-08-25
Here, with the use of optical traps it is possible to confine assemblies of colloidal particles in two-dimensional and quasi-one-dimensional arrays. Here we examine how colloidal particles rearrange in a quasi-one-dimensional trap with a time dependent confining potential. The particle motion occurs both through slow elastic uniaxial distortions as well as through abrupt large-scale two-dimensional avalanches associated with plastic rearrangements. During the avalanches the particle velocity distributions extend over a broad range and can be fit to a power law consistent with other studies of plastic events mediated by dislocations.
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Colloidal-gold electrosensor measuring device
Wegner, Steven; Harpold, Michael A.; McCaffrey, Terence M.; Morris, Susan E.; Wojciechowski, Marek; Zhao, Junguo; Henkens, Robert W.; Naser, Najih; O'Daly, John P.
1995-01-01
The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 .mu.g/dL in blood samples as small as 10 .mu.L.
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Colloidal silica films for high-capacity DNA arrays
NASA Astrophysics Data System (ADS)
Glazer, Marc Irving
The human genome project has greatly expanded the amount of genetic information available to researchers, but before this vast new source of data can be fully utilized, techniques for rapid, large-scale analysis of DNA and RNA must continue to develop. DNA arrays have emerged as a powerful new technology for analyzing genomic samples in a highly parallel format. The detection sensitivity of these arrays is dependent on the quantity and density of immobilized probe molecules. We have investigated substrates with a porous, "three-dimensional" surface layer as a means of increasing the surface area available for the synthesis of oligonucleotide probes, thereby increasing the number of available probes and the amount of detectable bound target. Porous colloidal silica films were created by two techniques. In the first approach, films were deposited by spin-coating silica colloid suspensions onto flat glass substrates, with the pores being formed by the natural voids between the solid particles (typically 23nm pores, 35% porosity). In the second approach, latex particles were co-deposited with the silica and then pyrolyzed, creating films with larger pores (36 nm), higher porosity (65%), and higher surface area. For 0.3 mum films, enhancements of eight to ten-fold and 12- to 14-fold were achieved with the pure silica films and the films "templated" with polymer latex, respectively. In gene expression assays for up to 7,000 genes using complex biological samples, the high-capacity films provided enhanced signals and performed equivalently or better than planar glass on all other functional measures, confirming that colloidal silica films are a promising platform for high-capacity DNA arrays. We have also investigated the kinetics of hybridization on planar glass and high-capacity substrates. Adsorption on planar arrays is similar to ideal Langmuir-type adsorption, although with an "overshoot" at high solution concentration. Hybridization on high-capacity films is controlled by traditional adsorption (ka) and desorption (kd) coefficients, as well as morphology factors and transient binding interactions between the target and probes. The strength of the transient probe/target binding interactions are on the order of 5--7 DNA base pairs, which suggests the formation of nucleation or other metastable complexes, rather than fully-zippered duplexes.
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A functional genomics approach reveals CHE as a component of the Arabidopsis circadian clock.
Pruneda-Paz, Jose L; Breton, Ghislain; Para, Alessia; Kay, Steve A
2009-03-13
Transcriptional feedback loops constitute the molecular circuitry of the plant circadian clock. In Arabidopsis, a core loop is established between CCA1 and TOC1. Although CCA1 directly represses TOC1, the TOC1 protein has no DNA binding domains, which suggests that it cannot directly regulate CCA1. We established a functional genomic strategy that led to the identification of CHE, a TCP transcription factor that binds specifically to the CCA1 promoter. CHE is a clock component partially redundant with LHY in the repression of CCA1. The expression of CHE is regulated by CCA1, thus adding a CCA1/CHE feedback loop to the Arabidopsis circadian network. Because CHE and TOC1 interact, and CHE binds to the CCA1 promoter, a molecular linkage between TOC1 and CCA1 gene regulation is established.
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NASA Astrophysics Data System (ADS)
Liu, Xiaoying; McBride, Sean P.; Jaeger, Heinrich M.; Nealey, Paul F.
2016-07-01
Hybrid nanomaterials comprised of well-organized arrays of colloidal semiconductor quantum dots (QDs) in close proximity to metal nanoparticles (NPs) represent an appealing system for high-performance, spectrum-tunable photon sources with controlled photoluminescence. Experimental realization of such materials requires well-defined QD arrays and precisely controlled QD-metal interspacing. This long-standing challenge is tackled through a strategy that synergistically combines lateral confinement and vertical stacking. Lithographically generated nanoscale patterns with tailored surface chemistry confine the QDs into well-organized arrays with high selectivity through chemical pattern directed assembly, while subsequent coating with a monolayer of close-packed Au NPs introduces the plasmonic component for fluorescence enhancement. The results show uniform fluorescence emission in large-area ordered arrays for the fabricated QD structures and demonstrate five-fold fluorescence amplification for red, yellow, and green QDs in the presence of the Au NP monolayer. Encapsulation of QDs with a silica shell is shown to extend the design space for reliable QD/metal coupling with stronger enhancement of 11 times through the tuning of QD-metal spatial separation. This approach provides new opportunities for designing hybrid nanomaterials with tailored array structures and multiple functionalities for applications such as multiplexed optical coding, color display, and quantum transduction.
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Calcium and ZmCCaMK are involved in brassinosteroid-induced antioxidant defense in maize leaves.
Yan, Jingwei; Guan, Li; Sun, Yue; Zhu, Yuan; Liu, Lei; Lu, Rui; Jiang, Mingyi; Tan, Mingpu; Zhang, Aying
2015-05-01
Brassinosteroids (BRs) have been shown to enhance stress tolerance by inducing antioxidant defense systems. However, the mechanisms of BR-induced antioxidant defense in plants remain to be determined. In this study, the role of calcium (Ca(2+)) and maize calcium/calmodulin-dependent protein kinase (CCaMK), ZmCCaMK, in BR-induced antioxidant defense, and the relationship between ZmCCaMK and Ca(2+) in BR signaling were investigated. BR treatment led to a significant increase in cytosolic Ca(2+) concentration in protoplasts from maize mesophyll, and Ca(2+) was shown to be required for BR-induced antioxidant defense. Treatment with BR induced increases in gene expression and enzyme activity of ZmCCaMK in maize leaves. Transient overexpression and silencing of ZmCCaMK in maize protoplasts demonstrated that ZmCCaMK was required for BR-induced antioxidant defense. The requirement for CCaMK was further investigated using a loss-of-function mutant of OsCCaMK, the orthologous gene of ZmCCaMK in rice. Consistent with the findings in maize, BR treatment could not induce antioxidant defense in the rice OsCCAMK mutant. Furthermore, Ca(2+) was required for BR-induced gene expression and activation of ZmCCaMK, while ZmCCaMK was shown to enhance the BR-induced increase in cytosolic Ca(2+) concentration. Moreover, our results also showed that ZmCCaMK and H2O2 influenced each other. These results indicate that Ca(2+) works together with ZmCCaMK in BR-induced antioxidant defense, and there are two positive feedback loops between Ca(2+) or H2O2 and ZmCCaMK in BR signaling in maize. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.
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Khoontawad, Jarinya; Pairojkul, Chawalit; Rucksaken, Rucksak; Pinlaor, Porntip; Wongkham, Chaisiri; Yongvanit, Puangrat; Pugkhem, Ake; Jones, Alun; Plieskatt, Jordan; Potriquet, Jeremy; Bethony, Jeffery; Pinlaor, Somchai; Mulvenna, Jason
2017-01-01
Parts of Southeast Asia have the highest incidence of intrahepatic cholangiocarcinoma (CCA) in the world because of infection by the liver fluke Opisthorchis viverrini (Ov). Ov-associated CCA is the culmination of chronic Ov-infection, with the persistent production of the growth factors and cytokines associated with persistent inflammation, which can endure for years in Ov-infected individuals prior to transitioning to CCA. Isobaric labeling and tandem mass spectrometry of liver tissue from a hamster model of CCA was used to compare protein expression profiles from inflammed tissue (Ovinfected but not cancerous) versus cancerous tissue (Ov-induced CCA). Immunohistochemistry and immunoblotting were used to verify dysregulated proteins in the animal model and in human tissue. We identified 154 dysregulated proteins that marked the transition from Ov-infection to Ov-induced CCA, i.e. proteins dysregulated during carcinogenesis but not Ov-infection. The verification of dysregulated proteins in resected liver tissue from humans with Ov-associated CCA showed the numerous parallels in protein dysregulation between human and animal models of Ov-induced CCA. To identify potential circulating markers for CCA, dysregulated proteins were compared with proteins isolated from exosomes secreted by a human CCA cell line (KKU055) and 27 proteins were identified as dysregulated in CCA and present in exosomes. These data form the basis of potential diagnostic biomarkers for human Ov-associated CCA. The profile of protein dysregulation observed during chronic Ovinfection and then in Ov-induced CCA provides insight into the etiology of an infection-induced inflammation-related cancer. PMID:28232516
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Suppression of thymosin β10 increases cell migration and metastasis of cholangiocarcinoma
2013-01-01
Background Thymosin β10 (Tβ10) expression is associated with malignant phenotypes in many cancers. However, the role and mechanisms of Tβ10 in liver fluke-associated cholangiocarcinoma (CCA) are not fully understood. In this study, we investigated the expression of Tβ10 in CCA tumor tissues and cell lines as well as molecular mechanisms of Tβ10 in tumor metastasis of CCA cell lines. Methods Tβ10 expression was determined by real time RT-PCR or immunocytochemistry. Tβ10 silence or overexpression in CCA cells was achieved using gene delivery techniques. Cell migration was assessed using modified Boyden chamber and wound healing assay. The effect of silencing Tβ10 on CCA tumor metastasis was determined in nude mice. Phosphorylation of ERK1/2 and the expression of EGR1, Snail and matrix metalloproteinases (MMPs) were studied. Results Ten pairs of CCA tissues (primary and metastatic tumors) and 5 CCA cell lines were studied. With real time RT-PCR and immunostaining analysis, Tβ10 was highly expressed in primary tumors of CCA; while it was relatively low in the metastatic tumors. Five CCA cell lines showed differential expression levels of Tβ10. Silence of Tβ10 significantly increased cell migration, invasion and wound healing of CCA cells in vitro; reversely, overexpression of Tβ10 reduced cell migration compared with control cells (P<0.05). In addition, silence of Tβ10 in CCA cells increased liver metastasis in a nude mouse model of CCA implantation into the spleen. Furthermore, silence of Tβ10 activated ERK1/2 and increased the expression of Snail and MMPs in CCA cell lines. Ras-GTPase inhibitor, FPT inhibitor III, effectively blocked Tβ10 silence-associated ERK1/2 activation, Snail expression and cell migration. Conclusions Low expression of Tβ10 is associated with metastatic phenotype of CCA in vitro and in vivo, which may be mediated by the activation of Ras, ERK1/2 and upregulation of Snail and MMPs. This study suggests a new molecular pathway of CCA pathogenesis and a novel strategy to treat or prevent CCA metastasis. PMID:24053380
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Localized and delocalized motion of colloidal particles on a magnetic bubble lattice.
Tierno, Pietro; Johansen, Tom H; Fischer, Thomas M
2007-07-20
We study the motion of paramagnetic colloidal particles placed above magnetic bubble domains of a uniaxial garnet film and driven through the lattice by external magnetic field modulation. An external tunable precessing field propels the particles either in localized orbits around the bubbles or in superdiffusive or ballistic motion through the bubble array. This motion results from the interplay between the driving rotating signal, the viscous drag force and the periodic magnetic energy landscape. We explain the transition in terms of the incommensurability between the transit frequency of the particle through a unit cell and the modulation frequency. Ballistic motion dynamically breaks the symmetry of the array and the phase locked particles follow one of the six crystal directions.
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Identification and characterization of Burkholderia multivorans CCA53.
Akita, Hironaga; Kimura, Zen-Ichiro; Yusoff, Mohd Zulkhairi Mohd; Nakashima, Nobutaka; Hoshino, Tamotsu
2017-07-06
A lignin-degrading bacterium, Burkholderia sp. CCA53, was previously isolated from leaf soil. The purpose of this study was to determine phenotypic and biochemical features of Burkholderia sp. CCA53. Multilocus sequence typing (MLST) analysis based on fragments of the atpD, gltD, gyrB, lepA, recA and trpB gene sequences was performed to identify Burkholderia sp. CCA53. The MLST analysis revealed that Burkholderia sp. CCA53 was tightly clustered with B. multivorans ATCC BAA-247 T . The quinone and cellular fatty acid profiles, carbon source utilization, growth temperature and pH were consistent with the characteristics of B. multivorans species. Burkholderia sp. CCA53 was therefore identified as B. multivorans CCA53.
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Hui Pan; Todd F. Shupe; Chung-Yun Hse
2009-01-01
CCA-treated wood was liquefied with polyethylene glycol/glycerin and sulfuric acid. The heavy metals were precipitated by Ca(OH)2 from liquefied CCA-treated wood. The original CCA-treated wood and precipitated wood sludge were fractionated by a modified BCR (Community Bureau of Reference) sequential extraction procedure. The purpose of the BCR...
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Critical role for CCA1 and LHY in maintaining circadian rhythmicity in Arabidopsis.
Alabadí, David; Yanovsky, Marcelo J; Más, Paloma; Harmer, Stacey L; Kay, Steve A
2002-04-30
Circadian clocks are autoregulatory, endogenous mechanisms that allow organisms, from bacteria to humans, to advantageously time a wide range of activities within 24-hr environmental cycles. CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY) are thought to be important components of the circadian clock in the model plant Arabidopsis. The similar circadian phenotypes of lines overexpressing either CCA1 or LHY have suggested that the functions of these two transcription factors are largely overlapping. cca1-1 plants, which lack CCA1 protein, show a short-period phenotype for the expression of several genes when assayed under constant light conditions. This suggests that LHY function is able to only partially compensate for the lack of CCA1 protein, resulting in a clock with a faster pace in cca1-1 plants. We have obtained plants lacking CCA1 and with LHY function strongly reduced, cca1-1 lhy-R, and show that these plants are unable to maintain sustained oscillations in both constant light and constant darkness. However, these plants exhibit some circadian function in light/dark cycles, showing that the Arabidopsis circadian clock is not entirely dependent on CCA1 and LHY activities.
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Kaewpitoon, Soraya J; Rujirakul, Ratana; Loyd, Ryan A; Panpimanmas, Sukij; Matrakool, Likit; Tongtawee, Taweesak; Kompor, Porntip; Norkaew, Jun; Chavengkun, Wasugree; Wakkhuwattapong, Parichart; Kujapun, Jirawoot; Ponphimai, Sukanya; Phatisena, Tanida; Eaksunti, Thawatchai; Polsripradist, Poowadol; Joosiri, Apinya; Sukkasam, Inchat; Padchasuwan, Natnapa; Kaewpitoon, Natthawut
2016-01-01
Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern region. Active surveillance in rural communities with an appropriat low-cost screening tool is required to facilitate early detection. Therefore, this study aimed to investigate the population at risk of CCA in Bua Yai district, Nakhon Ratchasima province, Northeastern Thailand using the Korat-CCA verbal screening test (KCVST) during June to October 2015. Reliability of KCVST demonstrated a Cronbach alpha coefficient=0.75 Stepwise-multiple regression showed that alcohol consumption was important for CCA screened, followed by agriculture and pesticide use, under-cooked cyprinoid fish consumption, praziquantel use, naïve northeastern people, opisthorchiasis, family relatives with CCA, and cholangitis or cholecystitis or gallstones, respectively. Population at risk for CCA was classified to low risk (63.4%), moderate risk (33.7%), and high risk (1.32%) for CCA. When CCA was screened using ultrasonography, 4 of 32 high risk participants had an abnormal biliary tract with dilated bile ducts. This study indicates that KCVST is a potential useful too which decrease the cost of large scale CCA screening.
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Jiao, Yong; Zhang, Yu; Wang, Yu; Wang, Bei; Jin, Jing; Wang, Xingyu
2018-05-01
Multiset canonical correlation analysis (MsetCCA) has been successfully applied to optimize the reference signals by extracting common features from multiple sets of electroencephalogram (EEG) for steady-state visual evoked potential (SSVEP) recognition in brain-computer interface application. To avoid extracting the possible noise components as common features, this study proposes a sophisticated extension of MsetCCA, called multilayer correlation maximization (MCM) model for further improving SSVEP recognition accuracy. MCM combines advantages of both CCA and MsetCCA by carrying out three layers of correlation maximization processes. The first layer is to extract the stimulus frequency-related information in using CCA between EEG samples and sine-cosine reference signals. The second layer is to learn reference signals by extracting the common features with MsetCCA. The third layer is to re-optimize the reference signals set in using CCA with sine-cosine reference signals again. Experimental study is implemented to validate effectiveness of the proposed MCM model in comparison with the standard CCA and MsetCCA algorithms. Superior performance of MCM demonstrates its promising potential for the development of an improved SSVEP-based brain-computer interface.
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Effects of corn cob ash on lime stabilized lateritic soil
NASA Astrophysics Data System (ADS)
Nnochiri, Emeka Segun
2018-03-01
This study assesses the effects of Corn Cob Ash (CCA) on lime-stabilized lateritic soil. Preliminary tests were carried out on the natural soil sample for purpose of identification and classification. Lime being the main stabilizing material was thoroughly mixed with the soil sample to determine the optimum lime requirement of the sample as a basis for evaluating the effects of the CCA. The optimum lime requirement was 10%. The CCA was thereafter added to the lime stabilized soil in varying proportions of 2, 4, 6, 8 and 10%. Unsoaked CBR increased from 83% at 0% CCA to highest value of 94% at 4% CCA. Unconfined Compressive Strength (UCS) values increased from 1123kN/m2 at 0% CCA to highest value of 1180kN/m2 at 4% CCA. It was therefore concluded that CCA can serve as a good complement for lime stabilization in lateritic soil.
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Hu, Shuyang; Ouyang, Qing; Cheng, Qingbao; Wang, Jinghan; Feng, Feiling; Qiao, Liang; Gan, Wei; Shi, Yang; Wu, Demin; Jiang, Xiaoqing
2018-04-01
Cholangiocarcinoma (CCA) is an aggressive malignant tumor and the prognosis of patients with advanced stage disease remains poor. Therefore, the identification of novel treatment agents for CCA is required. In the present study, the biological effects of the diabetes therapeutic agent, phenformin, in CCA cell lines was investigated. Cell Counting Kit‑8 cell viability, cellular clone formation and subcutaneous tumor formation assays were performed, which revealed that phenformin inhibited CCA cell proliferation and growth both in vitro and in vivo. In addition, phenformin induced CCA cell apoptosis and autophagy. Phenformin partly activated the liver kinase B1 (LKB1)/5' AMP‑activated protein kinase signaling pathway to exert its biological effects on CCA cell lines, as demonstrated by knockdown of LKB1, which reversed these effects. In conclusion, the present study demonstrated the biological effects of phenformin in CCA and suggested that phenformin may be a potential novel agent for CCA treatment.
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Colloidal assembly directed by virtual magnetic moulds
NASA Astrophysics Data System (ADS)
Demirörs, Ahmet F.; Pillai, Pramod P.; Kowalczyk, Bartlomiej; Grzybowski, Bartosz A.
2013-11-01
Interest in assemblies of colloidal particles has long been motivated by their applications in photonics, electronics, sensors and microlenses. Existing assembly schemes can position colloids of one type relatively flexibly into a range of desired structures, but it remains challenging to produce multicomponent lattices, clusters with precisely controlled symmetries and three-dimensional assemblies. A few schemes can efficiently produce complex colloidal structures, but they require system-specific procedures. Here we show that magnetic field microgradients established in a paramagnetic fluid can serve as `virtual moulds' to act as templates for the assembly of large numbers (~108) of both non-magnetic and magnetic colloidal particles with micrometre precision and typical yields of 80 to 90 per cent. We illustrate the versatility of this approach by producing single-component and multicomponent colloidal arrays, complex three-dimensional structures and a variety of colloidal molecules from polymeric particles, silica particles and live bacteria and by showing that all of these structures can be made permanent. In addition, although our magnetic moulds currently resemble optical traps in that they are limited to the manipulation of micrometre-sized objects, they are massively parallel and can manipulate non-magnetic and magnetic objects simultaneously in two and three dimensions.
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Inventions Utilizing Microfluidics and Colloidal Particles
NASA Technical Reports Server (NTRS)
Marr, David W.; Gong, Tieying; Oakey, John; Terray, Alexander V.; Wu, David T.
2009-01-01
Several related inventions pertain to families of devices that utilize microfluidics and/or colloidal particles to obtain useful physical effects. The families of devices can be summarized as follows: (1) Microfluidic pumps and/or valves wherein colloidal-size particles driven by electrical, magnetic, or optical fields serve as the principal moving parts that propel and/or direct the affected flows. (2) Devices that are similar to the aforementioned pumps and/or valves except that they are used to manipulate light instead of fluids. The colloidal particles in these devices are substantially constrained to move in a plane and are driven to spatially order them into arrays that function, variously, as waveguides, filters, or switches for optical signals. (3) Devices wherein the ultra-laminar nature of microfluidic flows is exploited to effect separation, sorting, or filtering of colloidal particles or biological cells in suspension. (4) Devices wherein a combination of confinement and applied electrical and/or optical fields forces the colloidal particles to become arranged into three-dimensional crystal lattices. Control of the colloidal crystalline structures could be exploited to control diffraction of light. (5) Microfluidic devices, incorporating fluid waveguides, wherein switching of flows among different paths would be accompanied by switching of optical signals.
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Tethered fleximags: a physical model for ciliary propulsion.
NASA Astrophysics Data System (ADS)
Du Roure, Olivia; Babataheri, Avin; Jenffer, Patrice; Fermigier, Marc; Goubault, Cecile
2007-11-01
Fleximags are linear colloidal structures made of micron-sized superparamagnetic particles. Permanent links between colloids are established through molecules grafted on the particles. The elasticity of the linker bestows a flexibility to the filament. The fleximags have already been used to make one of the first artificial microswimmers (Dreyfus et al. Nature 2005) resembling a spermatozoon. They can also be anchored to a glass substrate isolated or as arrays. Those arrays build up experimental models of the array of cilia on paramecium for studying physical aspects of the propulsion. Here we'll show our first studies concerning anchored flexiamgs submitted to time-dependent field. The actuation is controlled by three electromagnets and allowing all types of 3-D movements: (a)symmetric beating in a plane, rotation... We first study one single anchored fleximag when the field is rotating on a cone. Only a part of the filament is moving reflecting the competition between magnetic interactions, elasticity and viscosity. The length of this mobile fraction decreases with frequency. We also study the induced flow by PIV.
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Disruption of endocytic trafficking protein Rab7 impairs invasiveness of cholangiocarcinoma cells.
Suwandittakul, Nantana; Reamtong, Onrapak; Molee, Pattamaporn; Maneewatchararangsri, Santi; Sutherat, Maleerat; Chaisri, Urai; Wongkham, Sopit; Adisakwattana, Poom
2017-09-07
Alterations and mutations of endo-lysosomal trafficking proteins have been associated with cancer progression. Identification and characterization of endo-lysosomal trafficking proteins in invasive cholangiocarcinoma (CCA) cells may benefit prognosis and drug design for CCA. To identify and characterize endo-lysosomal trafficking proteins in invasive CCA. A lysosomal-enriched fraction was isolated from a TNF-α induced invasive CCA cell line (KKU-100) and uninduced control cells and protein identification was performed with nano-LC MS/MS. Novel lysosomal proteins that were upregulated in invasive CCA cells were validated by real-time RT-PCR. We selected Rab7 for further studies of protein level using western blotting and subcellular localization using immunofluorescence. The role of Rab7 in CCA invasion was determined by siRNA gene knockdown and matrigel transwell assay. Rab7 mRNA and protein were upregulated in invasive CCA cells compared with non-treated controls. Immunofluorescence studies demonstrated that Rab7 was expressed predominantly in invasive CCA cells and was localized in the cytoplasm and lysosomes. Suppression of Rab7 translation significantly inhibited TNF-α-induced cell invasion compared to non-treated control (p= 0.044). Overexpression of Rab7 in CCA cells was associated with cell invasion, supporting Rab7 as a novel candidate for the development of diagnostic and therapeutic strategies for CCA.
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Saxe, Jennifer K; Wannamaker, Eric J; Conklin, Scott W; Shupe, Todd F; Beck, Barbara D
2007-01-01
Chromated copper arsenate (CCA) treated wood has been used for more than 50 years. Recent attention has been focused on appropriate disposal of CCA-treated wood when its service life ends. Groups in the US and Europe concerned with the possibility of arsenic migration to groundwater from disposed CCA-treated wood have proposed that consumers be required to dispose of the wood as a hazardous waste, in the most protective of landfills. We examined available data for evidence of arsenic migration from unlined construction and demolition (C&D) debris landfills in Florida, where CCA-treated wood is disposed. Florida was chosen because soil, groundwater, landfill design, weather, and levels of CCA-treated wood use make the state a uniquely sensitive indicator for observing arsenic migration from CCA-treated wood disposal sites, should it occur. We developed and quality-checked a CCA-treated wood disposal model to estimate the amount of wood and associated arsenic disposed. By 2000, an estimated 13 million kg of arsenic in CCA-treated wood was disposed in Florida; however, groundwater monitoring data do not indicate that arsenic is migrating from unlined C&D landfills. Our results provide evidence that highly stringent regulation of CCA-treated wood disposal, such as treatment as a hazardous waste, is unnecessary.
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Raggi, Chiara; Correnti, Margherita; Sica, Antonio; Andersen, Jesper B.; Cardinale, Vincenzo; Alvaro, Domenico; Chiorino, Giovanna; Forti, Elisa; Glaser, Shannon; Alpini, Gianfranco; Destro, Annarita; Sozio, Francesca; Di Tommaso, Luca; Roncalli, Massimo; Banales, Jesus M.; Coulouarn, Cédric; Bujanda, Luis; Torzilli, Guido; Invernizzi, Pietro
2017-01-01
Background & Aims A therapeutically challenging subset of cells, termed cancer stem cells (CSCs) are responsible for cholangiocarcinoma (CCA) clinical severity. Presence of tumor-associated macrophages (TAMs) has prognostic significance in CCA and other malignancies. Thus, we hypothesized that CSCs may actively shape their tumor-supportive immune niche. Methods CCA cells were cultured in 3D conditions to generate spheres. CCA sphere analysis of in vivo tumorigenic-engraftment in immune-deficient mice and molecular characterization was performed. The in vitro and in vivo effect of CCA spheres on macrophage precursors was tested after culturing healthy donor cluster of differentiation (CD)14+ with CCA-sphere conditioned medium. Results CCA spheres engrafted in 100% of transplanted mice and revealed a significant 20.3-fold increase in tumor-initiating fraction (p = 0.0011) and a sustained tumorigenic potential through diverse xenograft-generations. Moreover, CCA spheres were highly enriched for CSC, liver cancer and embryonic stem cell markers both at gene and protein levels. Next, fluorescence-activated cell sorting analysis showed that in the presence of CCA sphere conditioned medium, CD14+ macrophages expressed key markers (CD68, CD115, human leukocyte antigen-D related, CD206) indicating that CCA sphere conditioned medium was a strong macrophage-activator. Gene expression profile of CCA sphere activated macrophages revealed unique molecular TAM-like features confirmed by high invasion capacity. Also, freshly isolated macrophages from CCA resections recapitulated a similar molecular phenotype of in vitro-educated macrophages. Consistent with invasive features, the largest CD163+ set was found in the tumor front of human CCA specimens (n = 23) and correlated with a high level of serum cancer antigen 19.9 (n = 17). Among mediators released by CCA spheres, only interleukin (IL)13, IL34 and osteoactivin were detected and further confirmed in CCA patient sera (n = 12). Surprisingly, a significant association of IL13, IL34 and osteoactivin with sphere stem-like genes was provided by a CCA database (n = 104). In vitro combination of IL13, IL34, osteoactivin was responsible for macrophage-differentiation and invasion, as well as for in vivo tumor-promoting effect. Conclusion CCA-CSCs molded a specific subset of stem-like associated macrophages thus providing a rationale for a synergistic therapeutic strategy for CCA-disease. Lay summary Immune plasticity represents an important hallmark of tumor outcome. Since cancer stem cells are able to manipulate stromal cells to their needs, a better definition of the key dysregulated immune subtypes responsible for cooperating in supporting tumor initiation may facilitate the development of new therapeutic approaches. Considering that human cholangiocarcinoma represents a clinical emergency, it is essential to move to predictive models in order to understand the adaptive process of macrophage component (imprinting, polarization and maintenance) engaged by tumor stem-like compartment. PMID:27593106
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Park, Haesung; Shin, Dongheok; Kang, Gumin; Baek, Seunghwa; Kim, Kyoungsik; Padilla, Willie J
2011-12-22
Based on conventional colloidal nanosphere lithography, we experimentally demonstrate novel graded-index nanostructures for broadband optical antireflection enhancement including the near-ultraviolet (NUV) region by integrating residual polystyrene antireflective (AR) nanoislands coating arrays with silicon nano-conical-frustum arrays. This is a feasible optimized integration method of two major approaches for antireflective surfaces: quarter-wavelength AR coating and biomimetic moth's eye structure. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Huo, Dezheng; Anderson, Diane; Palmer, Julie R; Herbst, Arthur L
2017-09-01
Women exposed to diethylstilbestrol (DES) in utero are at increased risk for the development of vaginal and cervical clear cell adenocarcinoma (CCA) at younger age. It is unknown if a second peak will occur in later life, the ages when CCA developed spontaneously in the pre-DES era. The complete epidemiologic curve of CCA has not been reported, yet. We reviewed 720 cases of CCA from the CCA registry at the University of Chicago through 2014. Incidence rates and cumulative risks for CCA were calculated based on white women born in the U.S. from 1948 through 1971. In 420 CCA cases there was documented evidence of prenatal DES exposure. 80% were among those between ages 15 and 31 but some occurred as late as age 55. A small second peak occurred around age 42. The risk of DES-related CCA was highest in the 1951-1956 birth cohort and this birth cohort effect closely correlated with DES prescriptions over time in the U.S. (r=0.98, P=0.005). By age 50, the cumulative risk of CCA was 1 per 750 exposed women. CCA cases without evidence of DES exposure had similar ages, year of diagnosis, and birth cohort patterns as the documented DES-exposed cases, suggesting that some negative cases were exposed. Their inclusion raises the cumulative risk of CCA to 1 per 520. With the largest data available, our results confirmed the association between prenatal DES exposure and clear cell adenocarcinoma. The study also refines the risks of DES-related CCA. Copyright © 2017 Elsevier Inc. All rights reserved.
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NASA Astrophysics Data System (ADS)
Kolacz, Jakub
We first explore the topology of liquid crystals and look at the fundamental limitations of liquid crystals in confined geometries. The properties of liquid crystal droplets are studied both theoretically and through simulations. We then demonstrate a method of chemically patterning surfaces that allows us to generate periodic arrays of micron-sized liquid crystal droplets and compare them to our simulation results. The parallelizable method of self-localizing liquid crystals using 2D chemical patterning developed here has applications in liquid crystal biosensors and lens arrays. We also present the first work looking at colloidal liquid crystals under the guise of thermophoresis. We observe that strong negative thermophoresis occurs in these systems and develop a theory based on elastic energy minimization. We also calculate a Soret coefficient two orders of magnitude larger than those present in the literature. This large Soret coefficient has considerable potential for improving thermophoretic sorting mechanisms such as Thermal-Field Flow Fractionation and MicroScale Thermophoresis. The final piece of this work demonstrates a method of using projection lithography to polymerize liquid crystal colloids with a defined internal director. While still a work in progress, there is potential for generating systems of active colloids that can change shape upon external stimulus and in the generation of self-folding shapes by selective polymerization and director predetermination in the vain of micro-kirigami.
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Mukkamalla, Shiva Kumar R; Naseri, Hussain M; Kim, Byung M; Katz, Steven C; Armenio, Vincent A
2018-04-01
Background: Cholangiocarcinoma (CCA) includes cancers arising from the intrahepatic and extrahepatic bile ducts. The etiology and pathogenesis of CCA remain poorly understood. This is the first study investigating both incidence patterns of CCA from 1973 through 2012 and demographic, clinical, and treatment variables affecting survival of patients with CCA. Patients and Methods: Using the SEER database, age-adjusted incidence rates were evaluated from 1973-2012 using SEER*Stat software. A retrospective cohort of 26,994 patients diagnosed with CCA from 1973-2008 was identified for survival analysis. Cox proportional hazards models were used to perform multivariate survival analysis. Results: Overall incidence of CCA increased by 65% from 1973-2012. Extrahepatic CCA (ECC) remained more common than intrahepatic CCA (ICC), whereas the incidence rates for ICC increased by 350% compared with a 20% increase seen with ECC. Men belonging to non-African American and non-Caucasian ethnicities had the highest incidence rates of CCA. This trend persisted throughout the study period, although African Americans and Caucasians saw 50% and 59% increases in incidence rates, respectively, compared with a 9% increase among other races. Median overall survival (OS) was 8 months in patients with ECC compared with 4 months in those with ICC. Our survival analysis found Hispanic women to have the best 5-year survival outcome ( P <.0001). OS diminished with age ( P <.0001), and ECC had better survival outcomes compared with ICC ( P <.0001). Patients who were married, were nonsmokers, belonged to a higher income class, and underwent surgery had better survival outcomes compared with others ( P <.0001). Conclusions: This is the most up-to-date study of CCA from the SEER registry that shows temporal patterns of increasing incidence of CCA across different races, sexes, and ethnicities. We identified age, sex, race, marital status, income, smoking status, anatomic location of CCA, tumor grade, tumor stage, radiation, and surgery as independent prognostic factors for OS in patients with CCA. Copyright © 2018 by the National Comprehensive Cancer Network.
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Trophic cascades result in large-scale coralline algae loss through differential grazer effects.
O'Leary, Jennifer K; McClanahan, Timothy R
2010-12-01
Removal of predators can have strong indirect effects on primary producers through trophic cascades. Crustose coralline algae (CCA) are major primary producers worldwide that may be influenced by predator removal through changes in grazer composition and biomass. CCA have been most widely studied in Caribbean and temperate reefs, where cover increases with increasing grazer biomass due to removal of competitive fleshy algae. However, each of these systems has one dominant grazer type, herbivorous fishes or sea urchins, which may not be functionally equivalent. Where fishes and sea urchins co-occur, fishing can result in a phase shift in the grazing community with subsequent effects on CCA and other substrata. Kenyan reefs have herbivorous fishes and sea urchins, providing an opportunity to determine the relative impacts of each grazer type and evaluate potential human-induced trophic cascades. We hypothesized that fish benefit CCA, abundant sea urchins erode CCA, and that fishing indirectly reduces CCA cover by removing sea urchin predators. We used closures and fished reefs as a large-scale, long-term natural experiment to assess how fishing and resultant changes in communities affect CCA abundance. We used a short-term caging experiment to directly test the effects of grazing on CCA. CCA cover declined with increasing fish and sea urchin abundance, but the negative impact of sea urchin grazing was much stronger than that of fishes. Abundant sea urchins reduced the CCA growth rate to almost zero and prevented CCA accumulation. A warming event (El Niño Southern Oscillation, ENSO) occurred during the 18-year study and had a strong but short-term positive effect on CCA cover. However, the effect of the ENSO on CCA was lower in magnitude than the effect of sea urchin grazing. We compare our results with worldwide literature on bioerosion by fishes and sea urchins. Grazer influence depends on whether benefits of fleshy algae removal outweigh costs of grazer-induced bioerosion. However, the cost-benefit ratio for CCA appears to change with grazer type, grazer abundance, and environment. In Kenya, predator removal leads to a trophic cascade that is expected to reduce net calcification of reefs and therefore reduce reef stability, growth, and resilience.
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Tan, Xin-Yu; Chang, Shi; Liu, Wei; Tang, Hui-Huan
2014-03-01
To evaluate the expression of CXC motif chemokine receptor 4 (CXCR4) in the tissues of patients with hilar cholangiocarcinoma (hilar-CCA) and to investigate the cell proliferation and frequency of neural invasion (NI) influenced by RNAi-mediated CXCR4 silencing. An immunohistochemical technique was used to detect the expression of CXCR4 in 41 clinical tissues, including hilar-CCA, cholangitis, and normal bile duct tissues. The effects of small interference RNA (siRNA)-mediated CXCR4 silencing were detected in the hilar-CCA cell line QBC939. Cell proliferation was determined by MTT. Expression of CXCR4 was monitored by quantitative real time polymerase chain reaction and Western blot analysis. The NI ability of hilar-CCA cells was evaluated using a perineural cell and hilar-CCA cell coculture migration assay. The expression of CXCR4 was significantly induced in clinical hilar-CCA tissue. There was a positive correlation between the expression of CXCR4 and lymph node metastasis/NI in hilar-CCA patients (p<0.05). Silencing of CXCR4 in tumor cell lines by siRNA led to significantly decreased NI (p<0.05) and slightly decreased cell proliferation. CXCR4 is likely correlated with clinical recurrence of hilar-CCA. CXCR4 is involved in the invasion and proliferation of human hilar-CCA cell line QBC939, indicating that CXCR4 could be a promising therapeutic target for hilar-CCA.
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Zhu, Yuan; Yan, Jingwei; Liu, Weijuan; ...
2016-05-10
Calcium/calmodulin-dependent protein kinase (CCaMK) has been shown to play an important role in abscisic acid (ABA)-induced antioxidant defense and enhance the tolerance of plants to drought stress. However, its downstream molecular events are poorly understood. Here, we identify a NAC transcription factor, ZmNAC84, in maize, which physically interacts with ZmCCaMK in vitro and in vivo. ZmNAC84 display a partially overlapping expression pattern with ZmCCaMK after ABA treatment and H 2O 2 is required for ABA-induced ZmNAC84 expression. Functional analysis reveals that ZmNAC84 is essential for ABA-induced antioxidant defense in a ZmCCaMK-dependent manner. Furthermore, ZmCCaMK directly phosphorylates S113 of ZmNAC84 inmore » vitro, and S113 is essential for the ABA-induced stimulation of antioxidant defense by ZmCCaMK. Moreover, overexpression of ZmNAC84 in tobacco can improve drought tolerance, and alleviate drought-induced oxidative damage of transgenic plants. These results define a mechanism for ZmCCaMK function in ABA-induced antioxidant defense, where ABA-produced H 2O 2 first induces expression of ZmCCaMK and ZmNAC84 and activates ZmCCaMK, and subsequently the activated ZmCCaMK phosphorylates ZmNAC84 at S113, thereby inducing antioxidant defense by activating downstream genes.« less
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Rattanasing, Wannaporn; Kaewpitoon, Soraya J; Loyd, Ryan A; Rujirakul, Ratana; Yodkaw, Eakachai; Kaewpitoon, Natthawut
2015-01-01
Cholangiocarcinoma (CCA) is a serious public health problem in the Northeast of Thailand. CCA is considered to be an incurable and rapidly lethal disease. Knowledge of the distribution of CCA patients is necessary for management strategies. This study aimed to utilize the Geographic Information System and Google EarthTM for distribution mapping of cholangiocarcinoma in Satuek District, Buriram, Thailand, during a 5-year period (2008-2012). In this retrospective study data were collected and reviewed from the OPD cards, definitive cases of CCA were patients who were treated in Satuek hospital and were diagnosed with CCA or ICD-10 code C22.1. CCA cases were used to analyze and calculate with ArcGIS 9.2, all of data were imported into Google Earth using the online web page www.earthpoint.us. Data were displayed at village points. A total of 53 cases were diagnosed and identified as CCA. The incidence was 53.57 per 100,000 population (65.5 for males and 30.8 for females) and the majority of CCA cases were in stages IV and IIA. The average age was 67 years old. The highest attack rate was observed in Thung Wang sub-district (161.4 per 100,000 population). The map display at village points for CCA patients based on Google Earth gave a clear visual deistribution. CCA is still a major problem in Satuek district, Buriram province of Thailand. The Google Earth production process is very simple and easy to learn. It is suitable for the use in further development of CCA management strategies.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Yuan; Yan, Jingwei; Liu, Weijuan
Calcium/calmodulin-dependent protein kinase (CCaMK) has been shown to play an important role in abscisic acid (ABA)-induced antioxidant defense and enhance the tolerance of plants to drought stress. However, its downstream molecular events are poorly understood. Here, we identify a NAC transcription factor, ZmNAC84, in maize, which physically interacts with ZmCCaMK in vitro and in vivo. ZmNAC84 display a partially overlapping expression pattern with ZmCCaMK after ABA treatment and H 2O 2 is required for ABA-induced ZmNAC84 expression. Functional analysis reveals that ZmNAC84 is essential for ABA-induced antioxidant defense in a ZmCCaMK-dependent manner. Furthermore, ZmCCaMK directly phosphorylates S113 of ZmNAC84 inmore » vitro, and S113 is essential for the ABA-induced stimulation of antioxidant defense by ZmCCaMK. Moreover, overexpression of ZmNAC84 in tobacco can improve drought tolerance, and alleviate drought-induced oxidative damage of transgenic plants. These results define a mechanism for ZmCCaMK function in ABA-induced antioxidant defense, where ABA-produced H 2O 2 first induces expression of ZmCCaMK and ZmNAC84 and activates ZmCCaMK, and subsequently the activated ZmCCaMK phosphorylates ZmNAC84 at S113, thereby inducing antioxidant defense by activating downstream genes.« less
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Chou, Selene; Colman, Joan; Tylenda, Carolyn; De Rosa, Christopher
2007-05-01
The Agency for Toxic Substances and Disease Registry (ATSDR) prepared this health consultation to provide support for assessing the public health implications of hazardous chemical exposure, primarily through drinking water, related to releases of chromated copper arsenate (CCA) in the port of Djibouti. CCA from a shipment, apparently intended for treating electric poles, is leaking into the soil in the port area. CCA is a pesticide used to protect wood against decay-causing organisms. This mixture commonly contains chromium(VI) (hexavalent chromium) as chromic acid, arsenic(V) (pentavalent arsenic) as arsenic pentoxide and copper (II) (divalent copper) as cupric oxide, often in an aqueous solution or concentrate. Experimental studies of the fate of CCA in soil and monitoring studies of wood-preserving sites where CCA was spilled on the soil indicate that the chromium(VI), arsenic and copper components of CCA can leach from soil into groundwater and surface water. In addition, at CCA wood-preserving sites, substantial concentrations of chromium(VI), arsenic and copper remained in the soil and were leachable into water four years after the use of CCA was discontinued, suggesting prolonged persistence in soil, with continued potential for leaching. The degree of leaching depended on soil composition and the extent of soil contamination with CCA. In general, leaching was highest for chromium(VI), intermediate for arsenic and lowest for copper. Thus, the potential for contamination of sources of drinking water exists. Although arsenic that is leached from CCA-contaminated soil into surface water may accumulate in the tissues of fish and shellfish, most of the arsenic in these animals will be in a form (often called fish arsenic) that is less harmful. Copper, which leaches less readily than the other components, can accumulate in tissues of mussels and oysters. Chromium is not likely to accumulate in the tissues of fish and shellfish. Limited studies of air concentrations during cleanup of CCA-contaminated soil at wood- preserving sites showed that air levels of chromium(VI), arsenic and copper were below the occupational standards. Workers directly involved in the repackaging, containment or cleanup of leaking containers of CCA or of soil saturated with CCA, however, may be exposed to high levels of CCA through direct dermal contact, inhalation of aerosols or particulates and inadvertent ingestion. Few studies have been conducted on the health effects of CCA. CCA as a concentrated solution is corrosive to the skin eyes and digestive tract. Studies of workers exposed to CCA in wood-preserving plants have not found adverse health effects in these workers, but the studies involved small numbers of workers and therefore are not definitive. People exposed to very high levels of CCA, from sawing wood that still had liquid CCA in it or from living in a home contaminated with ash containing high levels of chromium(VI), arsenic and copper, experienced serious health effects including nosebleeds, digestive system pain and bleeding, itching skin, darkened urine, nervous system effects such as tingling or numbness of the hands and feet and confusion, and rashes or thickening and peeling of the skin. These health effects of the mixture are at least qualitatively reflective of the health effects of the individual components of CCA (arsenic, chromium(VI) and copper). For a given mixture, the critical effects of the individual components are of particular concern, as are any effects in common that may become significant due to additivity or interactions among the components. Effects of concern for CCA, based on the known effects of the individual components, include cancer (arsenic by the oral route, arsenic and chromium(VI) by the inhalation route), irritant or corrosive effects (all three mixture components), the unique dermal effects of arsenic, neurologic effects (arsenic and chromium(VI), and hematologic, hepatic and renal effects (all three components). Because arsenic, chromium(VI), and copper components affect some of the same target organs, they may have additive toxicity toward those organs. Few studies have investigated the potential toxic interactions among the components (arsenic, chromium(VI) and copper) of CCA. The available interaction studies and also possible mechanisms of interaction were evaluated using a weight-of-evidence approach. The conclusion is that there is no strong evidence that interactions among the components of CCA will result in a marked increase in toxicity. This conclusion reflects a lack of well designed interaction studies as well as uncertainties regarding potential mechanisms of interaction. Confidence in the conclusion is low. Workers exposed to high levels of CCA during cleanup of leaking containers of CCA or soil heavily contaminated with CCA should wear protective clothing and respirators if air concentrations of arsenic are above 10 microg/m3. In addition, they should not eat, drink or use tobacco products during exposure to CCA, and should thoroughly wash after skin contact with CCA and before eating, drinking, using tobacco products or using restrooms. When protective clothing becomes contaminated with CCA, it should be changed, and the contaminated clothing should be disposed off in a manner approved for pesticide disposal. Workers should leave all protective clothing, including work shoes and boots, at the workplace, so that CCA will not be carried into their cars and homes, which would endanger other people. People not involved in the cleanup of the CCA and who are not wearing protective clothing should be prevented from entering contaminated areas. Leaking containers of CCA must be repackaged and contained to prevent direct exposure of on-site personnel; and contaminated soil needs to be removed to prevent the CCA from leaching into surface water and groundwater, thereby contaminating sources of drinking water.
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NASA Astrophysics Data System (ADS)
Messina, F.; Tosco, T.; Sethi, R.
2017-12-01
Colloidal transport and deposition in saturated porous media are phenomena of considerable importance in a large number of natural processes and engineering applications, such as the contaminant and microorganism propagation in aquifer systems, the development of innovative groundwater remediation technologies, air and water filtration, and many others. Therefore, a thorough understanding of particle filtration is essential for predicting the transport and fate of colloids in the subsurface environment. The removal efficiency of a filter is a key aspect for colloid transport in porous media. Several efforts were devoted to derive accurate correlations for the single collector efficiency, one of the key concept in the filtration theory. However, up scaling this parameter to the entire porous medium is still a challenge. The common up-scaling approach assumes the deposition to be independent of the transport history, which means that the collector efficiency is considered uniform along the porous medium. However, previous works showed that this approach is inadequate under unfavorable deposition conditions. This study demonstrates that it is not adequate even in the simplest case of favorable deposition. Computational Fluid Dynamics simulations were run for a simplify porous media geometry, composed of a vertical array of 50 identical spherical collectors. A combination of Lagrangian and Eulerian simulations were performed to analyze the particle transport under a broad range of parameters (i.e., particle size, particle density, water velocity). The results show the limits of the existing models to interpret the experimental data. In fact, the outcome evidenced that when particle deposition is not controlled by Brownian diffusion, non-exponential concentration profiles are retrieved, in contrast with the assumption of uniform efficiency. Moreover, when the deposition mechanisms of sedimentation and interception dominate, the efficiency of the first sphere of the column is significantly higher compared to the others, and then it declines along the array down to an asymptotic value. A more rigorous procedure to evaluate the filtration processes in presence of a series of collectors was developed, and a new correlation for the up-scaled removal efficiency of the entire array was derived and proposed.
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NASA Astrophysics Data System (ADS)
Mikhailov, I. I.; Tarasov, S. A.; Lamkin, I. A.; Tadtaev, P. O.; Kozlovich, L. I.; Solomonov, A. V.; Stepanov, E. M.
2016-08-01
The luminescent organic ITO/TPD/Alq3/Al structures and CdSe/ZnS quantum dots (QD) arrays were created. Electrical and optical properties of the samples were examined. The luminescence of the layers and QD arrays was shown in the range of wavelengths from 400 to 680 nm. Luminescent structures with phosphors corresponding to the emission standards with CRI>98 and with color temperature of 5500 K and 6504 K were created.
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Patterned Colloidal Photonic Crystals.
Hou, Jue; Li, Mingzhu; Song, Yanlin
2018-03-01
Colloidal photonic crystals (PCs) have been well developed because they are easy to prepare, cost-effective, and versatile with regards to modification and functionalization. Patterned colloidal PCs contribute a novel approach to constructing high-performance PC devices with unique structures and specific functions. In this review, an overview of the strategies for fabricating patterned colloidal PCs, including patterned substrate-induced assembly, inkjet printing, and selective immobilization and modification, is presented. The advantages of patterned PC devices are also discussed in detail, for example, improved detection sensitivity and response speed of the sensors, control over the flow direction and wicking rate of microfluidic channels, recognition of cross-reactive molecules through an array-patterned microchip, fabrication of display devices with tunable patterns, well-arranged RGB units, and wide viewing-angles, and the ability to construct anti-counterfeiting devices with different security strategies. Finally, the perspective of future developments and challenges is presented. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Alternatives to chromated copper arsenate (CCA) for residential construction.
Stan Lebow
2004-01-01
For decades chromated copper arsenate (CCA) was the primary preservative for treated wood used in residential construction. However, recent label changes submitted by CCA registrants will withdraw CCA from most residential applications. This action has increased interest in arsenic-free preservative systems that have been standardized by the American Wood Preserversâ...
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Bioremediation and degradation of CCA-treated wood waste.
Barbara L Illman; Vina W. Yang
2004-01-01
Bioprocessing CCA wood waste is an efficient and economical alternative to depositing the waste in landfills, especially if landfill restrictions on CCA waste are imposed nation wide. We have developed bioremediation and degradation technologies for microbial processing of CCA waste. The technologies are based on specially formulated inoculum of wood decay fungi,...
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Crustose coralline algae increased framework and diversity on ancient coral reefs.
Weiss, Anna; Martindale, Rowan C
2017-01-01
Crustose coralline algae (CCA) are key producers of carbonate sediment on reefs today. Despite their importance in modern reef ecosystems, the long-term relationship of CCA with reef development has not been quantitatively assessed in the fossil record. This study includes data from 128 Cenozoic coral reefs collected from the Paleobiology Database, the Paleoreefs Database, as well as the original literature and assesses the correlation of CCA abundance with taxonomic diversity (both corals and reef dwellers) and framework of fossil coral reefs. Chi-squared tests show reef type is significantly correlated with CCA abundance and post-hoc tests indicate higher involvement of CCA is associated with stronger reef structure. Additionally, general linear models show coral reefs with higher amounts of CCA had a higher diversity of reef-dwelling organisms. These data have important implications for paleoecology as they demonstrate that CCA increased building capacity, structural integrity, and diversity of ancient coral reefs. The analyses presented here demonstrate that the function of CCA on modern coral reefs is similar to their function on Cenozoic reefs; thus, studies of ancient coral reef collapse are even more meaningful as modern analogues.
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Tan, Xin-Yu; Chang, Shi; Liu, Wei
2014-01-01
Background/Aims To evaluate the expression of CXC motif chemokine receptor 4 (CXCR4) in the tissues of patients with hilar cholangiocarcinoma (hilar-CCA) and to investigate the cell proliferation and frequency of neural invasion (NI) influenced by RNAi-mediated CXCR4 silencing. Methods An immunohistochemical technique was used to detect the expression of CXCR4 in 41 clinical tissues, including hilar-CCA, cholangitis, and normal bile duct tissues. The effects of small interference RNA (siRNA)-mediated CXCR4 silencing were detected in the hilar-CCA cell line QBC939. Cell proliferation was determined by MTT. Expression of CXCR4 was monitored by quantitative real time polymerase chain reaction and Western blot analysis. The NI ability of hilar-CCA cells was evaluated using a perineural cell and hilar-CCA cell coculture migration assay. Results The expression of CXCR4 was significantly induced in clinical hilar-CCA tissue. There was a positive correlation between the expression of CXCR4 and lymph node metastasis/NI in hilar-CCA patients (p<0.05). Silencing of CXCR4 in tumor cell lines by siRNA led to significantly decreased NI (p<0.05) and slightly decreased cell proliferation. Conclusions CXCR4 is likely correlated with clinical recurrence of hilar-CCA. CXCR4 is involved in the invasion and proliferation of human hilar-CCA cell line QBC939, indicating that CXCR4 could be a promising therapeutic target for hilar-CCA. PMID:24672662
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Silakit, Runglawan; Loilome, Watcharin; Yongvanit, Puangrat; Thongchot, Suyanee; Sithithaworn, Paiboon; Boonmars, Thidarut; Koonmee, Supinda; Titapun, Attapol; Khuntikeo, Narong; Chamadol, Nittaya; Techasen, Anchalee; Namwat, Nisana
2017-08-01
Opisthorchis viverrini infection induces chronic inflammation in the bile ducts, leading to periductal fibrosis (PDF), which possibly associates to cholangiocarcinoma (CCA). Patients with CCA have a poor prognosis, which is linked to asymptomatic disease and late diagnosis. Hence, detecting early stage CCA is essential. Secretory miRNAs have been promoted as biomarkers for pathological changes associated with parasitic infections, fibrosis and/or cancer. We aimed to determine levels of miR-192 and miR-21 in the urine of O. viverrini infected, periductal fibrosis (PDF) and CCA groups using qRT-PCR. We found that miR-192 was significantly higher in O. viverrini infected, PDF and also CCA groups (p<0.05) than in healthy controls. By utilizing the Receiver Operation Characteristics (ROC) analysis, miR-192 differentiated patients with opisthorchiasis (the area under the curve; AUC=0.766), PDF subjects (AUC=0.781) and CCA patients (AUC=0.682) from healthy controls. MiR-21 was significantly higher in PDF and CCA groups (p<0.05) than in healthy controls. MiR-21 discriminated PDF subjects (AUC=0.735) and CCA patients (AUC=0.682) from healthy controls. Combined levels of these two miRNAs revealed an increased AUC of 0.812 for separating opisthorchiasis, AUC of 0.815 in discriminating PDF subjects, and AUC of 0.849 in differentiating CCA from healthy controls. Odds ratios (OR) indicated high levels of miR-192/miR-21 as risk predictors for opisthorchiasis, PDF and CCA. Levels of these miRNAs declined significantly for patients following praziquantel treatment. In conclusion, urinary miR-192/miR-21 have potential as risk indicators for opisthorchiasis and PDF-associated CCA in the endemic region. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Juszkat, Robert, E-mail: radiologiamim@wp.pl; Kulesza, Jerzy; Zarzecka, Anna
2011-02-15
To describe a technique for the preservation of the left common carotid artery (CCA) in zone 2 endovascular repair of thoracic aortic aneurysm. This technique involves the placement of a guide wire into the left CCA via the right brachial artery before stent graft deployment to enable precise visualization and protection of the left CCA during the whole procedure. Of the 107 patients with thoracic endovascular aortic repair in our study, 32 (30%) had the left subclavian artery intentionally covered (landing zone 2). Eight (25%) of those 32 had landing zone 2a-the segment distally the origin of the left CCA,more » halfway between the origin of the left CCA and the left subclavian artery. In all patients, a guide wire was positioned into the left CCA via the right brachial artery before stent graft deployment. It is a retrospective study in design. In seven patients, stent grafts were positioned precisely. In the remaining patient, the positioning was imprecise; the origin of the left CCA was partially covered by the graft. A stent was implanted into the left CCA to restore the flow into the vessel. All procedures were performed successfully. The technique of placing a guide wire into the left CCA via the right brachial artery before stent graft deployment is a safe and effective method that enables the precise visualization of the left CCA during the whole procedure. Moreover, in case of inadvertent complete or partial coverage of the origin of the left CCA, it supplies safe and quick access to the artery for stent implantation.« less
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Brown, C J; Eaton, R A
2001-04-01
The effect of the anti-marine-borer timber preservative chromated copper arsenate (CCA) (a pressure impregnated solution of copper, chromium and arsenic compounds) on non-target marine fouling animals was investigated during a subtidal exposure trial. Panels of Scots pine treated to target retentions of 12, 24 and 48 kg CCA per m-3 of wood, plus untreated controls were submerged at a coastal site on the south coast of the UK for 6, 12 and 18 months. After each exposure period the fouling communities that formed on the surface of panels were assessed both qualitatively and quantitatively. Community structure was similar on panels treated to the three CCA loadings, but was significantly different from community structure on untreated panels. The total number of species (species richness) was similar on all panels, although the number of individual organisms attached to the surface of panels was significantly higher on CCA-treated panels than on untreated panels. k-dominance curves revealed that the difference in numbers of individuals between CCA-treated and untreated panels was caused by higher numbers of the dominant species (Elminius modestus, Hydroides ezoensis, and Electra pilosa) on CCA-treated panels. Other species were present in similar numbers on panels of all treatments. Results indicate that there are no detrimental toxic effects to epibiota caused by the presence of CCA preservative within the matrix of the wood at any of the treatment levels. Differences in community structure between CCA-treated and untreated panels may be due to enhanced larval settlement on CCA-treated timber by some species as a result of modifications to the surface properties of the timber by the CCA preservative.
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NASA Technical Reports Server (NTRS)
Wang, W.; Poovaiah, B. W.
1999-01-01
A chimeric Ca2+/calmodulin-dependent protein kinase (CCaMK) was previously cloned and characterized in this laboratory. To investigate the biological functions of CCaMK, the yeast two-hybrid system was used to isolate genes encoding proteins that interact with CCaMK. One of the cDNA clones obtained from the screening (LlEF-1alpha1) has high similarity with the eukaryotic elongation factor-1alpha (EF-1alpha). CCaMK phosphorylated LlEF-1alpha1 in a Ca2+/calmodulin-dependent manner. The phosphorylation site for CCaMK (Thr-257) was identified by site-directed mutagenesis. Interestingly, Thr-257 is located in the putative tRNA-binding region of LlEF-1alpha1. An isoform of Ca2+-dependent protein kinase (CDPK) phosphorylated multiple sites of LlEF-1alpha1 in a Ca2+-dependent but calmodulin-independent manner. Unlike CDPK, CCaMK phosphorylated only one site, and this site is different from CDPK phosphorylation sites. This suggests that the phosphorylation of EF-1alpha by these two kinases may have different functional significance. Although the phosphorylation of LlEF-1alpha1 by CCaMK is Ca2+/calmodulin-dependent, in vitro binding assays revealed that CCaMK binds to LlEF-1alpha1 in a Ca2+-independent manner. This was further substantiated by coimmunoprecipitation of CCaMK and EF-1alpha using the protein extract from lily anthers. Dissociation of CCaMK from EF-1alpha by Ca2+ and phosphorylation of EF-1alpha by CCaMK in a Ca2+/calmodulin-dependent manner suggests that these interactions may play a role in regulating the biological functions of EF-1alpha.
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Goal-directed Hemostatic Resuscitation of Trauma-induced Coagulopathy
Gonzalez, Eduardo; Moore, Ernest E.; Moore, Hunter B.; Chapman, Michael P.; Chin, Theresa L.; Ghasabyan, Arsen; Wohlauer, Max V.; Barnett, Carlton C.; Bensard, Denis D.; Biffl, Walter L.; Burlew, Clay C.; Johnson, Jeffrey L.; Pieracci, Fredric M.; Jurkovich, Gregory J.; Banerjee, Anirban; Silliman, Christopher C.; Sauaia, Angela
2017-01-01
Background Massive transfusion protocols (MTPs) have become standard of care in the management of bleeding injured patients, yet strategies to guide them vary widely. We conducted a pragmatic, randomized clinical trial (RCT) to test the hypothesis that an MTP goal directed by the viscoelastic assay thrombelastography (TEG) improves survival compared with an MTP guided by conventional coagulation assays (CCA). Methods This RCT enrolled injured patients from an academic level-1 trauma center meeting criteria for MTP activation. Upon MTP activation, patients were randomized to be managed either by an MTP goal directed by TEG or by CCA (ie, international normalized ratio, fibrinogen, platelet count). Primary outcome was 28-day survival. Results One hundred eleven patients were included in an intent-to-treat analysis (TEG = 56, CCA = 55). Survival in the TEG group was significantly higher than the CCA group (log-rank P = 0.032, Wilcoxon P = 0.027); 20 deaths in the CCA group (36.4%) compared with 11 in the TEG group (19.6%) (P = 0.049). Most deaths occurred within the first 6 hours from arrival (21.8% CCA group vs 7.1% TEG group) (P = 0.032). CCA patients required similar number of red blood cell units as the TEG patients [CCA: 5.0 (2–11), TEG: 4.5 (2–8)] (P = 0.317), but more plasma units [CCA: 2.0 (0–4), TEG: 0.0 (0–3)] (P = 0.022), and more platelets units [CCA: 0.0 (0–1), TEG: 0.0 (0–0)] (P = 0.041) in the first 2 hours of resuscitation. Conclusions Utilization of a goal-directed, TEG-guided MTP to resuscitate severely injured patients improves survival compared with an MTP guided by CCA and utilizes less plasma and platelet transfusions during the early phase of resuscitation. PMID:26720428
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On the Shape of the Common Carotid Artery, with Implications for Blood Velocity Profiles
Manbachi, Amir; Hoi, Yiemeng; Wasserman, Bruce A.; Lakatta, Edward G.; Steinman, David A
2012-01-01
Clinical and engineering studies typically assume that the common carotid artery (CCA) is straight enough to assume fully developed flow, yet recent studies have demonstrated the presence of skewed velocity profiles. Towards elucidating the influence of mild vascular curvatures on blood flow patterns and atherosclerosis, the present study aimed to characterize the three-dimensional shape of the human CCA. The left and right carotid arteries of 28 participants (62±13 years) in the VALIDATE (Vascular Aging – The Link that Bridges Age to Atherosclerosis) study were digitally segmented from 3D contrast-enhanced magnetic resonance angiograms, from the aortic arch to the carotid bifurcation. Each CCA was divided into nominal cervical and thoracic segments, for which curvatures were estimated by least squares fitting of the respective centerlines to planar arcs. The cervical CCA had mean radius of curvature of 127 mm, corresponding to a mean lumen:curvature radius ratio of 1:50. The thoracic CCA was significantly more curved at 1:16, with the plane of curvature tilted by a mean angle of 25 degrees and rotated close to 90 degrees with respect to that of the cervical CCA. The left CCA was significantly longer and slightly more curved than the right CCA, and there was a weak but significant increase in CCA curvature with age. Computational fluid dynamic (CFD) simulations carried out for idealized CCA geometries derived from these and other measured geometric parameters demonstrated that mild cervical curvature is sufficient to prevent flow from fully developing, independent of the degree of thoracic curvature. These findings reinforce the idea that fully-developed flow may be the exception rather than the rule for the CCA, and perhaps other nominally long and straight vessels. PMID:22031538
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Islam, Rakibul M; Billah, Baki; Hossain, Md Nassif; Oldroyd, John
2017-01-01
Background: Cervical cancer (CCa) and breast cancer (BCa) are the two leading cancers in women worldwide. Early detection and education to promote early diagnosis and screening of CCa and BCa greatly increases the chances for successful treatment and survival. Screening uptake for CCa and BCa in low and middle - income countries (LMICs) is low, and is consequently failing to prevent these diseases. We conducted a systematic review to identify the key barriers to CCa and BCa screening in women in LMICs. Methods: We performed a systematic literature search using Ovid MEDLINE, EMBASE, PsycINFO, SCOPUS, CINHAL Plus, and Google scholar to retrieve all English language studies from inception to 2015. This review was done in accordance with the PRISMA-P guidelines. Results: 53 eligible studies, 31 CCa screening studies and 22 BCa screening studies, provided information on 81,210 participants. We found fewer studies in low-income and lower - middle - income countries than in upper - middle - income countries. Lack of knowledge about CCa and BCa, and understanding of the role of screening were the key barriers to CCa and BCa screening in LMICs. Factors that are opportunities for knowledge acquisition, such as level of education, urban living, employment outside the home, facilitated CCa and BCa screening uptake in women in LMICs. Conclusions: Improvements to CCa and BCa screening uptake in LMICs must be accompanied by educational interventions which aim to improve knowledge and understanding of CCa and BCa and screening to asymptomatic women. It is imperative for governments and health policy makers in LMICs to implement screening programmes, including educational interventions, to ensure the prevention and early detection of women with CCa and BCa. These programmes and policies will be an integral part of a comprehensive population-based CCa and BCa control framework in LMICs. PMID:28749101
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Islam, Rakibul M; Billah, Baki; Hossain, Md Nassif; Oldroyd, John
2017-07-27
Background: Cervical cancer (CCa) and breast cancer (BCa) are the two leading cancers in women worldwide. Early detection and education to promote early diagnosis and screening of CCa and BCa greatly increases the chances for successful treatment and survival. Screening uptake for CCa and BCa in low and middle - income countries (LMICs) is low, and is consequently failing to prevent these diseases. We conducted a systematic review to identify the key barriers to CCa and BCa screening in women in LMICs. Methods: We performed a systematic literature search using Ovid MEDLINE, EMBASE, PsycINFO, SCOPUS, CINHAL Plus, and Google scholar to retrieve all English language studies from inception to 2015. This review was done in accordance with the PRISMA-P guidelines. Results: 53 eligible studies, 31 CCa screening studies and 22 BCa screening studies, provided information on 81,210 participants. We found fewer studies in low-income and lower - middle - income countries than in upper - middle - income countries. Lack of knowledge about CCa and BCa, and understanding of the role of screening were the key barriers to CCa and BCa screening in LMICs. Factors that are opportunities for knowledge acquisition, such as level of education, urban living, employment outside the home, facilitated CCa and BCa screening uptake in women in LMICs. Conclusions: Improvements to CCa and BCa screening uptake in LMICs must be accompanied by educational interventions which aim to improve knowledge and understanding of CCa and BCa and screening to asymptomatic women. It is imperative for governments and health policy makers in LMICs to implement screening programmes, including educational interventions, to ensure the prevention and early detection of women with CCa and BCa. These programmes and policies will be an integral part of a comprehensive population-based CCa and BCa control framework in LMICs. Creative Commons Attribution License
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Evaluating spent CCA residential decks for second-life products
Robert Smith; David Bailey; Phil Araman
2003-01-01
The amount of CCA treated wood being removed from spent residential decks is increasing at a tremendous rate. While most spent CCA treated wood is being disposed in landfills, further useful and environmentally beneficial alternatives have to be met. This research estimated the percentage of recoverable lumber from spent CCA decks that can be recycled into other usable...
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Molla, Shahnawaz; Bhattacharjee, Subir
2007-10-09
The ability of dielectrophoretic (DEP) forces created using a microelectrode array to levitate particles in a colloidal suspension is studied experimentally and theoretically. The experimental system employs microfabricated electrode arrays on a glass substrate to apply repulsive DEP forces on polystyrene latex particles suspended in an aqueous medium. A numerical model based on the convection-diffusion-migration equation is presented to calculate the concentration distribution of colloidal particles in shear flow under the influence of a repulsive DEP force field. The results obtained from the numerical simulations are compared against trajectory analysis results and experimental data. The results indicate that by incorporating ac electric field-induced DEP forces in a shear flow, particle accumulation and deposition on the flow channel surfaces can be significantly reduced or even completely averted. The mathematical model is then used to indicate how the deposition behavior is modified in the presence of a permeable substrate, representative of tangential flow membrane filtration operations. The results indicate that the repulsive dielectrophoretic (DEP) forces imparted to the particles suspended in the feed can be employed to mitigate membrane fouling in a cross-flow filtration process.
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NASA Technical Reports Server (NTRS)
Poovaiah, B. W.; Xia, M.; Liu, Z.; Wang, W.; Yang, T.; Sathyanarayanan, P. V.; Franceschi, V. R.
1999-01-01
Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) was cloned from developing anthers of lily (Lilium longiflorum Thumb. cv. Nellie White) and tobacco (Nicotiana tabacum L. cv. Xanthi). Previous biochemical characterization and structure/function studies had revealed that CCaMK has dual modes of regulation by Ca(2+) and Ca(2+)/calmodulin. The unique structural features of CCaMK include a catalytic domain, a calmodulin-binding domain, and a neural visinin-like Ca(2+)-binding domain. The existence of these three features in a single polypeptide distinguishes it from other kinases. Western analysis revealed that CCaMK is expressed in a stage-specific manner in developing anthers. Expression of CCaMK was first detected in pollen mother cells and continued to increase, reaching a peak around the tetrad stage of meiosis. Following microsporogenesis, CCaMK expression rapidly decreased and at later stages of microspore development, no expression was detected. A tobacco genomic clone of CCaMK was isolated and transgenic tobacco plants were produced carrying the CCaMK promoter fused to the beta-glucuronidase reporter gene. Both CCaMK mRNA and protein were detected in the pollen sac and their localizations were restricted to the pollen mother cells and tapetal cells. Consistent results showing a stage-specific expression pattern were obtained by beta-glucuronidase analysis, in-situ hybridization and immunolocalization. The stage- and tissue-specific appearance of CCaMK in anthers suggests that it could play a role in sensing transient changes in free Ca(2+) concentration in target cells, thereby controlling developmental events in the anther.
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CpG-island methylation study of liver fluke-related cholangiocarcinoma
Sriraksa, R; Zeller, C; El-Bahrawy, M A; Dai, W; Daduang, J; Jearanaikoon, P; Chau-in, S; Brown, R; Limpaiboon, T
2011-01-01
Background: Genetic changes have been widely reported in association with cholangiocarcinoma (CCA), while epigenetic changes are poorly characterised. We aimed to further evaluate CpG-island hypermethylation in CCA at candidate loci, which may have potential as diagnostic or prognostic biomarkers. Methods: We analysed methylation of 26 CpG-islands in 102 liver fluke related-CCA and 29 adjacent normal samples using methylation-specific PCR (MSP). Methylation of interest loci was confirmed using pyrosequencing and/or combined bisulfite restriction analysis, and protein expression by immunohistochemistry. Results: A number of CpG-islands (OPCML, SFRP1, HIC1, PTEN and DcR1) showed frequency of hypermethylation in >28% of CCA, but not adjacent normal tissues. The results showed that 91% of CCA were methylated in at least one CpG-island. The OPCML was the most frequently methylated locus (72.5%) and was more frequently methylated in less differentiated CCA. Patients with methylated DcR1 had significantly longer overall survival (Median; 41.7 vs 21.7 weeks, P=0.027). Low-protein expression was found in >70% of CCA with methylation of OPCML or DcR1. Conclusion: Aberrant hypermethylation of certain loci is a common event in liver fluke-related CCA and may potentially contribute to cholangiocarcinogenesis. The OPCML and DcR1 might serve as methylation biomarkers in CCA that can be readily examined by MSP. PMID:21448164
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Songserm, Nopparat; Woradet, Somkiattiyos; Charoenbut, Pattaraporn
2016-01-01
Cholangiocarcinoma (CCA) caused by opisthorchiasis is a specific public health problem in the Greater Mekong subregional countries. The Northeast Thailand is considered a world's prime area of CCA. Many epidemiological studies found the association between fruit and vegetables consumption and CCA, but their results were inconclusive. Therefore, this meta-analysis aimed to investigate the relationship between fruit and vegetables consumption and CCA prevention in the Northeast Thailand. The authors conducted a comprehensive search of scholarships on MEDLINE, EMBASE, and SCOPUS published during 1990 and 2015. Selected studies about fruit and vegetables consumption and CCA were analyzed. The fixed-effect model was used to estimate pool odds ratios for the consumption vs. nonconsumption. Based on a meta-analysis, consumption of mixed fruit [odds ratio (OR) = 0.79; 95% confidence interval (CI): 0.65-0.96], mixed vegetables (OR = 0.61; 95% CI: 0.50-0.75), and combined fruit and vegetables (OR = 0.68; 95% CI: 0.57-0.80) was associated with the reduction of CCA risk statistically. These findings support that fruit and vegetables consumption is associated with CCA risk reduction. If implemented in a larger geographical area, the study will shed light on possibilities to future reduction of CCA. Educators can replicate the study to solve CCA or other types of cancer and discover the best practice.
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Takeda, Naoya; Maekawa, Takaki; Hayashi, Makoto
2012-01-01
The common symbiosis pathway is at the core of symbiosis signaling between plants and soil microbes. In this pathway, calcium- and calmodulin-dependent protein kinase (CCaMK) plays a crucial role in integrating the signals both in arbuscular mycorrhizal symbiosis (AMS) and in root nodule symbiosis (RNS). However, the molecular mechanism by which CCaMK coordinates AMS and RNS is largely unknown. Here, we report that the gain-of-function (GOF) variants of CCaMK without the regulatory domains activate both AMS and RNS signaling pathways in the absence of symbiotic partners. This activation requires nuclear localization of CCaMK. Enforced nuclear localization of the GOF-CCaMK variants by fusion with a canonical nuclear localization signal enhances signaling activity of AMS and RNS. The GOF-CCaMK variant triggers formation of a structure similar to the prepenetration apparatus, which guides infection of arbuscular mycorrhizal fungi to host root cells. In addition, the GOF-CCaMK variants without the regulatory domains partly restore AMS but fail to support rhizobial infection in ccamk mutants. These data indicate that AMS, the more ancient type of symbiosis, can be mainly regulated by the kinase activity of CCaMK, whereas RNS, which evolved more recently, requires complex regulation performed by the regulatory domains of CCaMK. PMID:22337918
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Mechanical and chemical properties of CCA-treated lumber removed from spent residential decks
Robert L. Smith; David Bailey; Philip A. Araman
2007-01-01
The amount of chromated copper arsenate (CCA)- treated wood being removed from spent residential decks is increasing at a tremendous rate. While most spent CCA-treated wood is being disposed in landfills, further useful and environmentally beneficial alternatives have to be met. If the volume of CCA-treated wood reaching landfills continues to rise, stricter disposal...
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Long-term soil accumulation of chromium, copper, and arsenic adjacent to preservative-treated wood.
S. Lebow; D. Foster; J. Evans
2004-01-01
Chromated copper arsenate (CCA) treated wood has been used extensively in outdoor applications. The Environmental Protection Agency (EPA) and CCA producers recently reached an agreement to limit future use of CCA for some types of applications. One area of concern is the long-term accumulation of leached CCA in soil adjacent to treated wood structures. Interpreting...
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Consumer willingness to pay for a naturally decay-resistant wood product.
Geoffrey Donovan; Hayley Hesseln
2004-01-01
Chromated copper arsenate (CCA) is the most widely used chemical wood preservative in the United States. Concerns about the safety of CCA led to an agreement between the Environmental Protection Agency and the wood treatment industry to withdraw CCA for nonindustrial uses by the end of 2003. In light of the publicity surrounding the withdrawal of CCA, this article...
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Ronald Sabo; Altaf H. Basta; Jerrold E. Winandy
2013-01-01
Public health awareness has increased in the past few years regarding the disposal of chromated copper arsenate (CCA) preservative-treated wood wastes. This study demonstrates the potential for using remediated CCA lumber and alternative fiber sources, such as sugar cane bagasse, to produce medium density fiberboard (MDF). The role of both remediated CCA loaded spruce...
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in Vitro and in Vivo Inhibitory Effects of α-Mangostin on Cholangiocarcinoma Cells and Allografts
Aukkanimart, Ratchadawan; Boonmars, Thidarut; Sriraj, Pranee; Sripan, Panupan; Songsri, Jiraporn; Ratanasuwan, Panaratana; Laummaunwai, Porntip; Boueroy, Parichart; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara; Boonjaraspinyo, Sirintip; Wu, Zhiliang; Hahnvajanawong, Chariya; Vaeteewoottacharn, Kulthida; Wongkham, Sopit
2017-01-01
We investigated the anti-cholangiocarcinoma effect of α-mangostin from Garcinia mangostana pericarp extract (GM) in a human cholangiocarcinoma (CCA) cell line and a hamster CCA allograft model. In vitro, human CCA cells were treated with GM at various concentrations and for different time periods; then cell-cycle arrest and apoptosis were evaluated using flow cytometry, and metastatic potential with wound healing assays. In vivo, hamster allografts were treated with GM, gemcitabine (positive control) and a placebo (negative control) for 1 month; tumor weight and volume were then determined. Histopathological features and immunostaining (CK19 and PCNA) characteristics were examined by microscopy. The present study found that α-mangostin could: inhibit CCA cell proliferation by inducing apoptosis through the mitochondrial pathway; induce G1 cell-cycle arrest; and inhibit metastasis. Moreover, α-mangostin could inhibit CCA growth, i.e. reduce tumor mass (weight and size) and alter CCA pathology, as evidenced by reduced positive staining for CK19 and PCNA. The present study thus suggested that α-mangostin is a promising anti-CCA compound whose ready availability in tropical countries might indicate use for prevention and treatment of CCA. PMID:28441703
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Satomura, Hironori; Adachi, Kohei
2013-07-01
To facilitate the interpretation of canonical correlation analysis (CCA) solutions, procedures have been proposed in which CCA solutions are orthogonally rotated to a simple structure. In this paper, we consider oblique rotation for CCA to provide solutions that are much easier to interpret, though only orthogonal rotation is allowed in the existing formulations of CCA. Our task is thus to reformulate CCA so that its solutions have the freedom of oblique rotation. Such a task can be achieved using Yanai's (Jpn. J. Behaviormetrics 1:46-54, 1974; J. Jpn. Stat. Soc. 11:43-53, 1981) generalized coefficient of determination for the objective function to be maximized in CCA. The resulting solutions are proved to include the existing orthogonal ones as special cases and to be rotated obliquely without affecting the objective function value, where ten Berge's (Psychometrika 48:519-523, 1983) theorems on suborthonormal matrices are used. A real data example demonstrates that the proposed oblique rotation can provide simple, easily interpreted CCA solutions.
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Goeree, Ron; Blackhouse, Gord; Bowen, James M; O'Reilly, Daria; Sutherland, Simone; Hopkins, Robert; Chow, Benjamin; Freeman, Michael; Provost, Yves; Dennie, Carole; Cohen, Eric; Marcuzzi, Dan; Iwanochko, Robert; Moody, Alan; Paul, Narinder; Parker, John D
2013-10-01
Conventional coronary angiography (CCA) is the standard diagnostic for coronary artery disease (CAD), but multi-detector computed tomography coronary angiography (CTCA) is a non-invasive alternative. A multi-center coverage with evidence development study was undertaken and combined with an economic model to estimate the cost-effectiveness of CTCA followed by CCA vs CCA alone. Alternative assumptions were tested in patient scenario and sensitivity analyses. CCA was found to dominate CTCA, however, CTCA was relatively more cost-effective in females, in advancing age, in patients with lower pre-test probabilities of CAD, the higher the sensitivity of CTCA and the lower the probability of undergoing a confirmatory CCA following a positive CTCA. RESULTS were very sensitive to alternative patient populations and modeling assumptions. Careful consideration of patient characteristics, procedures to improve the diagnostic yield of CTCA and selective use of CCA following CTCA will impact whether CTCA is cost-effective or dominates CCA.
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DNA Origami Patterned Colloids for Programmed Design and Chirality
NASA Astrophysics Data System (ADS)
Ben Zion, Matan Yah; He, Xiaojin; Maass, Corinna; Sha, Ruojie; Seeman, Ned; Chaikin, Paul
Micron size colloidal particles are scientifically important as model systems for equilibrium and active systems in physics, chemistry and biology and for technologies ranging from catalysis to photonics. The past decade has seen development of new particles with directional patches, lock and key reactions and specific recognition that guide assembly of structures such as complex crystalline arrays. What remains lacking is the ability to self-assemble structures of arbitrary shape with specific chirality, placement and orientation of neighbors. Here we demonstrate the adaptation of DNA origami nanotechnology to the micron colloidal scale with designed control of neighbor type, placement and dihedral angle. We use DNA origami belts with programmed flexibility, and functionality to pattern colloidal surfaces and bind particles to specific sites at specific angles and make uniquely right handed or left handed structures. The hybrid DNA origami colloid technology should allow the synthesis of designed functional structural and active materials. This work was supported as part of the Center for Bio-Inspired Energy Science, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0000989.
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Lörincz, András; Póczos, Barnabás
2003-06-01
In optimizations the dimension of the problem may severely, sometimes exponentially increase optimization time. Parametric function approximatiors (FAPPs) have been suggested to overcome this problem. Here, a novel FAPP, cost component analysis (CCA) is described. In CCA, the search space is resampled according to the Boltzmann distribution generated by the energy landscape. That is, CCA converts the optimization problem to density estimation. Structure of the induced density is searched by independent component analysis (ICA). The advantage of CCA is that each independent ICA component can be optimized separately. In turn, (i) CCA intends to partition the original problem into subproblems and (ii) separating (partitioning) the original optimization problem into subproblems may serve interpretation. Most importantly, (iii) CCA may give rise to high gains in optimization time. Numerical simulations illustrate the working of the algorithm.
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Magnetic assembly route to colloidal responsive photonic nanostructures.
He, Le; Wang, Mingsheng; Ge, Jianping; Yin, Yadong
2012-09-18
Responsive photonic structures can respond to external stimuli by transmitting optical signals. Because of their important technological applications such as color signage and displays, biological and chemical sensors, security devices, ink and paints, military camouflage, and various optoelectronic devices, researchers have focused on developing these functional materials. Conventionally, self-assembled colloidal crystals containing periodically arranged dielectric materials have served as the predominant starting frameworks. Stimulus-responsive materials are incorporated into the periodic structures either as the initial building blocks or as the surrounding matrix so that the photonic properties can be tuned. Although researchers have proposed various versions of responsive photonic structures, the low efficiency of fabrication through self-assembly, narrow tunability, slow responses to the external stimuli, incomplete reversibility, and the challenge of integrating them into existing photonic devices have limited their practical application. In this Account, we describe how magnetic fields can guide the assembly of superparamagnetic colloidal building blocks into periodically arranged particle arrays and how the photonic properties of the resulting structures can be reversibly tuned by manipulating the external magnetic fields. The application of the external magnetic field instantly induces a strong magnetic dipole-dipole interparticle attraction within the dispersion of superparamagnetic particles, which creates one-dimensional chains that each contains a string of particles. The balance between the magnetic attraction and the interparticle repulsions, such as the electrostatic force, defines the interparticle separation. By employing uniform superparamagnetic particles of appropriate sizes and surface charges, we can create one-dimensional periodicity, which leads to strong optical diffraction. Acting remotely over a large distance, magnetic forces drove the rapid formation of colloidal photonic arrays with a wide range of interparticle spacing. They also allowed instant tuning of the photonic properties because they manipulated the interparticle force balance, which changed the orientation of the colloidal assemblies or their periodicity. This magnetically responsive photonic system provides a new platform for chromatic applications: these colloidal particles assemble instantly into ordered arrays with widely, rapidly, and reversibly tunable structural colors, which can be easily and rapidly fixed in a curable polymer matrix. Based on these unique features, we demonstrated many applications of this system, such as structural color printing, the fabrication of anticounterfeiting devices, switchable signage, and field-responsive color displays. We also extended this idea to rapidly organize uniform nonmagnetic building blocks into photonic structures. Using a stable ferrofluid of highly charged magnetic nanoparticles, we created virtual magnetic moments inside the nonmagnetic particles. This "magnetic hole" strategy greatly broadens the scope of the magnetic assembly approach to the fabrication of tunable photonic structures from various dielectric materials.
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Spent CCA treated wood from residential decks can be a resource for reuse and recycling
Robert L Smith; Philip A. Araman; David Bailey; Matthew F. Winn
2005-01-01
The volume of CCA treated wood being disposed of in landfills is growing at an alarming rate. In order to reduce the demand on landfills and timber harvest, more environmentally responsible alternatives for spent CCA treated wood have to be addressed. The objective of this study was to determine feasible products that can be produced from CCA treated wood....
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Due to the potential for ingestion of chromated copper arsenate (CCA) by the hand-to-mouth activities of young children who contact CCA treated wood, EPA has used wipe samples to study the potential benefits of paint-like coatings on CCA treated wood. Citizens who may be concern...
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Gene Expression in Plant Lipid Metabolism in Arabidopsis Seedlings
Hsiao, An-Shan; Haslam, Richard P.; Michaelson, Louise V.; Liao, Pan; Napier, Johnathan A.; Chye, Mee-Len
2014-01-01
Events in plant lipid metabolism are important during seedling establishment. As it has not been experimentally verified whether lipid metabolism in 2- and 5-day-old Arabidopsis thaliana seedlings is diurnally-controlled, quantitative real-time PCR analysis was used to investigate the expression of target genes in acyl-lipid transfer, β-oxidation and triacylglycerol (TAG) synthesis and hydrolysis in wild-type Arabidopsis WS and Col-0. In both WS and Col-0, ACYL-COA-BINDING PROTEIN3 (ACBP3), DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1) and DGAT3 showed diurnal control in 2- and 5-day-old seedlings. Also, COMATOSE (CTS) was diurnally regulated in 2-day-old seedlings and LONG-CHAIN ACYL-COA SYNTHETASE6 (LACS6) in 5-day-old seedlings in both WS and Col-0. Subsequently, the effect of CIRCADIAN CLOCK ASSOCIATED1 (CCA1) and LATE ELONGATED HYPOCOTYL (LHY) from the core clock system was examined using the cca1lhy mutant and CCA1-overexpressing (CCA1-OX) lines versus wild-type WS and Col-0, respectively. Results revealed differential gene expression in lipid metabolism between 2- and 5-day-old mutant and wild-type WS seedlings, as well as between CCA1-OX and wild-type Col-0. Of the ACBPs, ACBP3 displayed the most significant changes between cca1lhy and WS and between CCA1-OX and Col-0, consistent with previous reports that ACBP3 is greatly affected by light/dark cycling. Evidence of oil body retention in 4- and 5-day-old seedlings of the cca1lhy mutant in comparison to WS indicated the effect of cca1lhy on storage lipid reserve mobilization. Lipid profiling revealed differences in primary lipid metabolism, namely in TAG, fatty acid methyl ester and acyl-CoA contents amongst cca1lhy, CCA1-OX, and wild-type seedlings. Taken together, this study demonstrates that lipid metabolism is subject to diurnal regulation in the early stages of seedling development in Arabidopsis. PMID:25264899
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Porta, Tiffany; Grivet, Chantal; Knochenmuss, Richard; Varesio, Emmanuel; Hopfgartner, Gérard
2011-02-01
Analysis of low molecular weight compounds (LMWC) in complex matrices by vacuum matrix-assisted laser desorption/ionization (MALDI) often suffers from matrix interferences, which can severely degrade limits of quantitation. It is, therefore, useful to have available a range of suitable matrices, which exhibit complementary regions of interference. Two newly synthesized α-cyanocinnamic acid derivatives are reported here; (E)-2-cyano-3-(naphthalen-2-yl)acrylic acid (NpCCA) and (2E)-3-(anthracen-9-yl)-2-cyanoprop-2enoic acid (AnCCA). Along with the commonly used α-cyano-4-hydroxycinnamic acid (CHCA), and the recently developed 4-chloro-α-cyanocinnamic acid (Cl-CCA) matrices, these constitute a chemically similar series of matrices covering a range of molecular weights, and with correspondingly differing ranges of spectral interference. Their performance was compared by measuring the signal-to-noise ratios (S/N) of 47 analytes, mostly pharmaceuticals, with the different matrices using the selected reaction monitoring (SRM) mode on a triple quadrupole instrument equipped with a vacuum MALDI source. AnCCA, NpCCA and Cl-CCA were found to offer better signal-to-noise ratios in SRM mode than CHCA, but Cl-CCA yielded the best results for 60% of the compounds tested. To better understand the relative performance of this matrix series, the proton affinities (PAs) were measured using the kinetic method. Their relative values were: AnCCA > CHCA > NpCCA > Cl-CCA. This ordering is consistent with the performance data. The synthesis of the new matrices is straightforward and they provide (1) tunability of matrix background interfering ions and (2) enhanced analyte response for certain classes of compounds. Copyright © 2011 John Wiley & Sons, Ltd.
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Rucksaken, Rucksak; Pairojkul, Chawalit; Pinlaor, Porntip; Khuntikeo, Narong; Roytrakul, Sittiruk; Selmi, Carlo; Pinlaor, Somchai
2014-01-01
The diagnosis of cholangiocarcinoma (CCA) is often challenging, leading to poor prognosis. CCA arises via chronic inflammation which may be associated with autoantibodies production. This study aims to identify IgG antibodies directed at self-proteins and tumor-associated antigens. Proteins derived from immortalized cholangiocyte cell line (MMNK1) and CCA cell lines (M055, M214 and M139) were separated using 2-dimensional electrophoresis and incubated with pooled plasma of patients with CCA and non-neoplastic controls by immunoblotting. Twenty five immunoreactive spots against all cell lines-derived proteins were observed on stained gels and studied by LC-MS/MS. Among these, heat shock protein 70 (HSP70), enolase 1 (ENO1) and ribonuclease/angiogenin inhibitor 1 (RNH1) obtained the highest matching scores and were thus selected for further validation. Western blot revealed immunoreactivity against HSP70 and RNH1 in the majority of CCA cases and weakly in healthy individuals. Further, ELISA showed that plasma HSP70 autoantibody level in CCA was significantly capable to discriminate CCA from healthy individuals with an area under the receiver operating characteristic curve of 0.9158 (cut-off 0.2630, 93.55% sensitivity and 73.91% specificity). Plasma levels of IgG autoantibodies against HSP70 were correlated with progression from healthy individuals to cholangitis to CCA (r = 0.679, P<0.001). In addition, circulating ENO1 and RNH1 autoantibodies levels were also significantly higher in cholangitis and CCA compared to healthy controls (P<0.05). Moreover, the combinations of HSP70, ENO1 or RNH1 autoantibodies positivity rates improved specificity to over 78%. In conclusion, plasma IgG autoantibodies against HSP70, ENO1 and RNH1 may represent new diagnostic markers for CCA. PMID:25058392
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Ko, Dae Kwan; Rohozinski, Dominica; Song, Qingxin; Taylor, Samuel H; Juenger, Thomas E; Harmon, Frank G; Chen, Z Jeffrey
2016-07-01
Heterosis has been widely used in agriculture, but the molecular mechanism for this remains largely elusive. In Arabidopsis hybrids and allopolyploids, increased photosynthetic and metabolic activities are linked to altered expression of circadian clock regulators, including CIRCADIAN CLOCK ASSOCIATED1 (CCA1). It is unknown whether a similar mechanism mediates heterosis in maize hybrids. Here we report that higher levels of carbon fixation and starch accumulation in the maize hybrids are associated with altered temporal gene expression. Two maize CCA1 homologs, ZmCCA1a and ZmCCA1b, are diurnally up-regulated in the hybrids. Expressing ZmCCA1 complements the cca1 mutant phenotype in Arabidopsis, and overexpressing ZmCCA1b disrupts circadian rhythms and biomass heterosis. Furthermore, overexpressing ZmCCA1b in maize reduced chlorophyll content and plant height. Reduced height stems from reduced node elongation but not total node number in both greenhouse and field conditions. Phenotypes are less severe in the field than in the greenhouse, suggesting that enhanced light and/or metabolic activities in the field can compensate for altered circadian regulation in growth vigor. Chromatin immunoprecipitation-sequencing (ChIP-seq) analysis reveals a temporal shift of ZmCCA1-binding targets to the early morning in the hybrids, suggesting that activation of morning-phased genes in the hybrids promotes photosynthesis and growth vigor. This temporal shift of ZmCCA1-binding targets correlated with nonadditive and additive gene expression in early and late stages of seedling development. These results could guide breeding better hybrid crops to meet the growing demand in food and bioenergy.
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Rabiul Islam, Md; Khademul Islam Molla, Md; Nakanishi, Masaki; Tanaka, Toshihisa
2017-04-01
Recently developed effective methods for detection commands of steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) that need calibration for visual stimuli, which cause more time and fatigue prior to the use, as the number of commands increases. This paper develops a novel unsupervised method based on canonical correlation analysis (CCA) for accurate detection of stimulus frequency. A novel unsupervised technique termed as binary subband CCA (BsCCA) is implemented in a multiband approach to enhance the frequency recognition performance of SSVEP. In BsCCA, two subbands are used and a CCA-based correlation coefficient is computed for the individual subbands. In addition, a reduced set of artificial reference signals is used to calculate CCA for the second subband. The analyzing SSVEP is decomposed into multiple subband and the BsCCA is implemented for each one. Then, the overall recognition score is determined by a weighted sum of the canonical correlation coefficients obtained from each band. A 12-class SSVEP dataset (frequency range: 9.25-14.75 Hz with an interval of 0.5 Hz) for ten healthy subjects are used to evaluate the performance of the proposed method. The results suggest that BsCCA significantly improves the performance of SSVEP-based BCI compared to the state-of-the-art methods. The proposed method is an unsupervised approach with averaged information transfer rate (ITR) of 77.04 bits min -1 across 10 subjects. The maximum individual ITR is 107.55 bits min -1 for 12-class SSVEP dataset, whereas, the ITR of 69.29 and 69.44 bits min -1 are achieved with CCA and NCCA respectively. The statistical test shows that the proposed unsupervised method significantly improves the performance of the SSVEP-based BCI. It can be usable in real world applications.
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Meng, Fanyin; DeMorrow, Sharon; Venter, Julie; Frampton, Gabriel; Han, Yuyan; Francis, Heather; Standeford, Holly; Avila, Shanika; McDaniel, Kelly; McMillin, Matthew; Afroze, Syeda; Guerrier, Micheleine; Quezada, Morgan; Ray, Debolina; Kennedy, Lindsey; Hargrove, Laura; Glaser, Shannon; Alpini, Gianfranco
2014-05-01
Substance P (SP) promotes cholangiocyte growth during cholestasis by activating its receptor, NK1R. SP is a proteolytic product of tachykinin (Tac1) and is deactivated by membrane metalloendopeptidase (MME). This study aimed to evaluate the functional role of SP in the regulation of cholangiocarcinoma (CCA) growth. NK1R, Tac1, and MME expression and SP secretion were assessed in human CCA cells and nonmalignant cholangiocytes. The proliferative effects of SP (in the absence/presence of the NK1R inhibitor, L-733,060) and of L-733,060 were evaluated. In vivo, the effect of L-733,060 treatment or MME overexpression on tumor growth was evaluated by using a xenograft model of CCA in nu/nu nude mice. The expression of Tac1, MME, NK1R, PCNA, CK-19, and VEGF-A was analyzed in the resulting tumors. Human CCA cell lines had increased expression of Tac1 and NK1R, along with reduced levels of MME compared with nonmalignant cholangiocytes, resulting in a subsequent increase in SP secretion. SP treatment increased CCA cell proliferation in vitro, which was blocked by L-733,060. Treatment with L-733,060 alone inhibited CCA proliferation in vitro and in vivo. Xenograft tumors derived from MME-overexpressed human Mz-ChA-1 CCA cells had a slower growth rate than those derived from control cells. Expression of PCNA, CK-19, and VEGF-A decreased, whereas MME expression increased in the xenograft tumors treated with L-733,060 or MME-overexpressed xenograft tumors compared with controls. The study suggests that SP secreted by CCA promotes CCA growth via autocrine pathway. Blockade of SP secretion and NK1R signaling may be important for the management of CCA.
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Fabrication of Periodic Gold Nanocup Arrays Using Colloidal Lithography
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeVetter, Brent M.; Bernacki, Bruce E.; Bennett, Wendy D.
Within recent years, the field of plasmonics has exploded as researchers have demonstrated exciting applications related to chemical and optical sensing in combination with new nanofabrication techniques. A plasmon is a quantum of charge density oscillation that lends nanoscale metals such as gold and silver unique optical properties. In particular, gold and silver nanoparticles exhibit localized surface plasmon resonances—collective charge density oscillations on the surface of the nanoparticle—in the visible spectrum. Here, we focus on the fabrication of periodic arrays of anisotropic plasmonic nanostructures. These half-shell (or nanocup) structures can exhibit additional unique light-bending and polarization dependent optical properties thatmore » simple isotropic nanostructures cannot. Researchers are interested in the fabrication of periodic arrays of nanocups for a wide variety of applications such as low-cost optical devices, surface-enhanced Raman scattering, and tamper indication. We present a scalable technique based on colloidal lithography in which it is possible to easily fabricate large periodic arrays of nanocups using spin-coating and self-assembled commercially available polymeric nanospheres. Electron microscopy and optical spectroscopy from the visible to near-IR was performed to confirm successful nanocup fabrication. We conclude with a demonstration of the transfer of nanocups to a flexible, conformal adhesive film.« less
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STATs profiling reveals predominantly-activated STAT3 in cholangiocarcinoma genesis and progression.
Dokduang, Hasaya; Techasen, Anchalee; Namwat, Nisana; Khuntikeo, Narong; Pairojkul, Chawalit; Murakami, Yoshinori; Loilome, Watcharin; Yongvanit, Puangrat
2014-10-01
We investigated the aberrant expression of the STAT family in humans and liver fluke (Opisthorchis viverrini, Ov)-induced hamster cholangiocarcinoma (CCA) tissues. The expression and phosphorylation of STAT1, STAT2, STAT3, STAT4, STAT5a, STAT5b and STAT6 in human hamster CCA tissues were immunohistochemistry-profiled. Localizations of STAT5 in macrophages and lipopolysaccharide (LPS)-induced macrophage-conditioned media mediated STAT3 activation in CCA cells were demonstrated. The expressions of STAT 1-4 and 6 were detected in the cytoplasm of hyperplastic bile ducts and tumor cells, whereas STAT5a and STAT5b were observed in macrophages and connective tissues surrounding tumor, respectively. The expressions of STAT3 and STAT5b were significantly observed in tumors with a poorer histological differentiation. STAT3 expression was significantly associated with shorter survival of CCA patients and was predominately activated in CCA cell lines. In the CCA-hamsters, STATs expression was gradually increased along the carcinogenesis, especially at 30 days post-infection in which the inflammatory response was markedly observed, showing the correlation between the inflammation and STATs activation. Moreover, LPS-induced macrophage-conditioned media could mediate STAT3 activation in CCA cells. STAT3 is the major STAT, which plays roles in the inflammation that contributes to CCA carcinogenesis and progression and may serve as a marker for a poor prognosis of CCA. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.
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Khripach, L V; Mikhaylova, R I; Koganova, Z I; Knyazeva, T D; Alekseeva, A V; Savostikova, O N; Ryzhova, I N; Kruglova, E V; Revzova, T L
2015-01-01
There are discussed the changes of an array of indices of the oxidative status in chronic administration of colloidal calcium carbonate preparation with faucet and low-mineralized drinking water to rats. Slight differences between significant effects of administration of 3 and 30 mg/L of preparation permit to suggest that the process of its incoming delivery into organism of rats has a bottleneck in the nature of total capacity of macrophages of intestinal lymphoid tissue to absorption of particles.
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Factors affecting sodium hypochlorite extraction of CCA from treated wood.
Gezer, E D; Cooper, P A
2009-12-01
Significant amounts of chromated copper arsenate (CCA) treated wood products, such as utility poles and residential construction wood, remain in service. There is increasing public concern about environmental contamination from CCA-treated wood when it is removed from service for reuse or recycling, placed in landfills or burned in commercial incinerators. In this paper, we investigated the effects of time, temperature and sodium hypochlorite concentration on chromium oxidation and extraction of chromated copper arsenate from CCA-treated wood (Type C) removed from service. Of the conditions evaluated, reaction of milled wood with sodium hypochlorite for one hour at room temperature followed by heating at 75 degrees C for two hours gave the highest extraction efficiency. An average of 95% Cr, 99% Cu and 96% As could be removed from CCA-treated, milled wood by this process. Most of the extracted chromium was oxidized to the hexavalent state and could therefore be recycled in a CCA treating solution. Sodium hypochlorite extracting solutions could be reused several times to extract CCA components from additional treated wood samples.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kazi, Feroz Kabir M.; Cooper, Paul A.
The volume of chromated copper arsenate (CCA) treated wood products coming out of service is expected to increase dramatically during the next decade. There is a need for an alternative waste management approach to landfilling. This paper investigates the variables affecting extraction of CCA components from wood particles and the potential to oxidize and reuse the recovered chemicals. Most of the CCA components could be extracted by 10% H{sub 2}O{sub 2} at 50 deg. C in 6 h with an average extraction efficiency of 95% for Cr, 94% for Cu and 98% for As. The extract containing Cr{sup III}, Cu{supmore » II} and As{sup V} could be oxidized in several stages by aqueous 2.5% w/w H{sub 2}O{sub 2} in less than 2 h to a condition where it was compatible with CCA treating solutions and could be reused for treating new wood. When the recovered extract was mixed with fresh CCA solution in different ratios, the mixed CCA-C solutions had similar solution stability as freshly prepared CCA-C solution and treated wood had similar leaching properties as wood treated with fresh solution.« less
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Zhao, Xiaoyu; Wen, Jiahong; Zhang, Mengning; Wang, Dunhui; Wang, Yaxin; Chen, Lei; Zhang, Yongjun; Yang, Jinghai; Du, Youwei
2017-03-01
An easy-handling and low-cost method is utilized to controllably fabricate nanopattern arrays as the surface-enhanced Raman scattering (SERS) active substrates with high density of SERS-active areas (hot spots). A hybrid silver array of nanocaps and nanotriangles are prepared by combining magnetron sputtering and plasma etching. By adjusting the etching time of polystyrene (PS) colloid spheres array in silver nanobowls, the morphology of the arrays can be easily manipulated to control the formation and distribution of hot spots. The experimental results show that the hybrid nanostructural arrays have large enhancement factor, which is estimated to be seven times larger than that in the array of nanocaps and three times larger than that in the array of nanorings and nanoparticles. According to the results of finite-difference time-domain simulation, the excellent SERS performance of this array is ascribed to the high density of hot spots and enhanced electromagnetic field.
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Slovut, David P; Romero, Javier M; Hannon, Kathleen M; Dick, James; Jaff, Michael R
2010-01-01
Severe stenosis of the common carotid artery (CCA), while uncommon, is associated with increased risk of transient ischemic attack and stroke. To date, no validated duplex ultrasound criteria have been established for grading the severity of CCA stenosis. The goal of this study was to use receiver-operating curve (ROC) analysis with computed tomographic angiography as the reference standard to establish duplex ultrasound criteria for diagnosing >or=50% CCA stenosis. The study cohort included 64 patients (42 men, 22 women) with a mean age of 65 +/- 12 years (range, 16-89 years) who had CCA peak systolic velocity (PSV) >or=150 cm/sec and underwent computed tomographic angiography (CTA) of the cervical and intracerebral vessels within 1 month of the duplex examination. One study was excluded because the CTA was technically inadequate, whereas another was excluded because the patient underwent bilateral CCA stenting. The CCA ipsilateral to any of the following was excluded from the analysis: innominate artery occlusion (n = 1), previous stenting of the ICA or CCA (n = 7), carotid endarterectomy (n = 1), or carotid-to-carotid bypass (n = 1). Thus, the data set included 62 patients and 115 vessels. Bland-Altman analysis was used to examine the agreement between two measures of luminal reduction measured by CTA: percent diameter stenosis and percent area stenosis. Receiver operating characteristic (ROC) analysis was used to determine optimal PSV and EDV thresholds for diagnosing >or=50% CCA stenosis. Severity of CCA stenosis was <50% in 76 vessels, 50%-59% in eight, 60%-69% in eight, 70%-79% in nine, 80%-89% in three, 90%-99% in five, and occluded in six. Duplex ultrasonography identified six of six (100%) patients with 100% CCA occlusion by CTA. Bland-Altman analysis showed poor agreement between percent stenosis determined by vessel diameter compared with percent stenosis determined by reduction in lumen area. Therefore, subsequent analysis was performed using percent stenosis by area. ROC analysis of different PSV thresholds for detecting stenosis >or=50% showed that >182 cm/sec was the most accurate with a sensitivity of 64% and specificity of 88% (P < .0001). Sensitivity, specificity, and accuracy of carotid duplex were higher when the stenosis was located in the mid or distal aspects of the CCA (sensitivity 76%, specificity 89%, area under curve 0.84, P < .001) than in the intrathoracic and proximal segment of the artery (P = NS). ROC analysis of different EDV thresholds for detecting CCA stenosis >or=50% showed that >30 cm/sec was the most accurate with a sensitivity of 54% and a specificity of 74% (P < .0239). Duplex ultrasonography is highly sensitive, specific, and accurate for detecting CCA lesions in the mid and distal CCA. Use of peak systolic velocity may lead to improved detection of CCA disease and initiation of appropriate therapy to reduce the risk of stroke. Copyright 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.
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Bubenhofer, S B; Athanassiou, E K; Grass, R N; Koehler, F M; Rossier, M; Stark, W J
2009-12-02
Two-particle colloids containing nanomagnets and microscale mirrors can be prepared from iron oxide nanoparticles, microscale metal flakes and high-density liquids stabilizing the mirror suspension against sedimentation by matching the constituent's density. The free Brownian rotation of the micromirrors can be magnetically controlled through an anisotropic change in impulse transport arising from impacts of the magnetic nanoparticles onto the anisotropic flakes. The resulting rapid mirror orientation allows large changes in light transmission and switchable optical reflectivity. The preparation of a passive display was conceptually demonstrated through colloid confinement in a planar cavity over an array of individually addressable solenoids and resulted in 4 x 4 digit displays with a reaction time of less than 100 ms.
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Information storage and retrieval in a single levitating colloidal particle
NASA Astrophysics Data System (ADS)
Myers, Christopher J.; Celebrano, Michele; Krishnan, Madhavi
2015-10-01
The binary switch is a basic component of digital information. From phase-change alloys to nanomechanical beams, molecules and atoms, new strategies for controlled bistability hold great interest for emerging technologies. We present a generic methodology for precise and parallel spatiotemporal control of nanometre-scale matter in a fluid, and demonstrate the ability to attain digital functionalities such as switching, gating and data storage in a single colloid, with further implications for signal amplification and logic operations. This fluid-phase bit can be arrayed at high densities, manipulated by either electrical or optical fields, supports low-energy, high-speed operation and marks a first step toward ‘colloidal information’. The principle generalizes to any system where spatial perturbation of a particle elicits a differential response amenable to readout.
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Information storage and retrieval in a single levitating colloidal particle.
Myers, Christopher J; Celebrano, Michele; Krishnan, Madhavi
2015-10-01
The binary switch is a basic component of digital information. From phase-change alloys to nanomechanical beams, molecules and atoms, new strategies for controlled bistability hold great interest for emerging technologies. We present a generic methodology for precise and parallel spatiotemporal control of nanometre-scale matter in a fluid, and demonstrate the ability to attain digital functionalities such as switching, gating and data storage in a single colloid, with further implications for signal amplification and logic operations. This fluid-phase bit can be arrayed at high densities, manipulated by either electrical or optical fields, supports low-energy, high-speed operation and marks a first step toward 'colloidal information'. The principle generalizes to any system where spatial perturbation of a particle elicits a differential response amenable to readout.
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Site-Specific Colloidal Crystal Nucleation by Template-enhanced Particle Transport
NASA Astrophysics Data System (ADS)
Mishra, Chandan K.; Sood, A. K.; Ganapathy, Rajesh
The deliberate positioning of nano- and microstructures on surfaces is often a prerequisite for fabricating functional devices. While template-assisted nucleation is a promising route to self-assemble these structures, its success hinges on particles reaching target sites prior to nucleation and for nano/microscale particles, this is hampered by their small surface mobilities. We tailored surface features, which in the presence of attractive depletion interactions not only directed micrometer-sized colloids to specific sites but also subsequently guided their growth into ordered crystalline arrays of well-defined size and symmetry. By following the nucleation kinetics with single-particle resolution, we demonstrate control over nucleation density in a growth regime that has hitherto remained inaccessible. Our findings pave the way towards realizing non-trivial surface architectures composed of complex colloids/nanoparticles as well.
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PRESERVATIVE LEACHING FROM WEATHERED CCA-TREATED WOOD
Disposal of discarded CCA-treated wood in landfills raises concerns with respect to leaching of preservative compounds. When unweathered CCA-treated wood is leached using the toxicity characteristic leaching procedure (TCLP), arsenic concentrations exceed the toxicity characteris...
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Mohamed, S; Flint, S; Palmer, J; Fletcher, G C; Pitt, J I
2013-09-01
A simple and rapid screening method was developed for the detection of citrinin in fungal cultures using Coconut Cream Agar (CCA) described previously for detecting aflatoxin and ochratoxin A. Fifteen isolates of Penicillium citrinum were inoculated onto CCA and incubated at 25 and 30°C for 10 days. All isolates produced a distinct yellow green fluorescence on CCA when the reverse side of the agar plates were viewed under long wavelength UV light. Detection was optimal at 25°C after four to 5 days of incubation. Isolates positive by the CCA method also tested positive for citrinin production by the TLC agar plug method after growth on CCA, Czapek yeast extract agar and yeast extract sucrose agar. Control cultures were negative by both methods, indicating that the CCA Petri dish method was suitable for screening cultures for citrinin production. © 2013 The Society for Applied Microbiology.
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2D mesoscale colloidal crystal patterns on polymer substrates
NASA Astrophysics Data System (ADS)
Bredikhin, Vladimir; Bityurin, Nikita
2018-05-01
The development of nanosphere lithography relies on the ability of depositing 2D colloidal crystals comprising micro- and nano-size elements on substrates of different materials. One of the most difficult problems here is deposition of coatings on hydrophobic substrates, e.g. polymers, from aqueous colloidal solutions. We use UV photooxidation for substrate hydrophilization. We demonstrate a new method of producing a two-dimensional ordered array of polymer microparticles (polystyrene microspheres ∼1 μm in diameter) on a polymer substrate (PMMA). We show that implementation of the new deposition technique for directed self-assembly of microspheres on an UV irradiated surface provides an opportunity to obtain coatings on a hydrophilized PMMA surface of large area (∼5 cm2). UV irradiation of the surface through masks allows creating 2D patterns consisting of mesoscale elements formed by the deposited self-assembled microparticles owing to the fact that the colloidal particles are deposited only on the irradiated area leaving the non-irradiated sections intact.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Cullen, W.R.; McBride, B.C.; Pickett, A.W.
The wood preservative chromated copper arsenate (CCA) is a very widely used product. As it contains both copper and arsenic, it is not dissimilar to the pigments Scheele's green and Schweinfurter's green which were found to be biologically convertible to the toxic Gosio gas (B. Gosio, Ber. 30:1024-1026, 1897) later identified by Challenger and co-workers as trimethylarsine (F. Challenger, Adv. Enzymol. 12:429-491, 1951). Thus, it was of interest to determine whether microbiological action on CCA and wood treated with CCA could result in the production of trimethylarsine. The authors report that the fungus Candida humicola will produce this arsine frommore » dilute solutions of CCA and from wood soaked in CCA. 12 references.« less
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In situ changes of tropical crustose coralline algae along carbon dioxide gradients
NASA Astrophysics Data System (ADS)
Fabricius, K. E.; Kluibenschedl, A.; Harrington, L.; Noonan, S.; de'Ath, G.
2015-04-01
Crustose coralline algae (CCA) fulfill important ecosystem functions in coral reefs, including reef framework stabilization and induction of larval settlement. To investigate in situ the effects of high carbon dioxide on CCA communities, we deployed settlement tiles at three tropical volcanic CO2 seeps in Papua New Guinea along gradients spanning from 8.1 to 7.4 pH. After 5 and 13 months deployment, there was a steep transition from CCA presence to absence around pH 7.8 (660 μatm pCO2): 98% of tiles had CCA at pH > 7.8, whereas only 20% of tiles had CCA at pH <= 7.8. As pH declined from 8.0 to 7.8, the least and most sensitive CCA species lost 43% and 85% of cover, respectively. Communities on upward facing surfaces exposed to high light and high grazing pressure showed less steep losses than those on shaded surfaces with low grazing. Direct CO2 effects on early life stages were the main mechanisms determining CCA cover, rather than competitive interactions with other benthic groups. Importantly, declines were steepest at near-ambient pH, suggesting that CCA may have already declined in abundance due to the recent seawater pH decline of 0.1 units, and that future severe losses are likely with increasing ocean acidification.
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Wang, Jian-Zheng; Zhu, Yu-Xia; Ma, Hui-Chao; Chen, Si-Nan; Chao, Ji-Ye; Ruan, Wen-Ding; Wang, Duo; Du, Feng-guang; Meng, Yue-Zhong
2016-05-01
In this work, a 3D MCTS-CCA system was constructed by culturing multi-cellular tumor spheroid (MCTS) in the chitosan/collagen/alginate (CCA) fibrous scaffold for anticancer drug screening. The CCA scaffolds were fabricated by spray-spinning. The interactions between the components of the spray-spun fibers were evidenced by methods of Coomassie Blue stain, X-ray diffraction (XRD) and Fourier transform-infrared spectroscopy (FTIR). Co-culture indicated that MCF-7 cells showed a spatial growth pattern of multi-cellular tumor spheroid (MCTS) in the CCA fibrous scaffold with increased proliferation rate and drug-resistance to MMC, ADM and 5-Aza comparing with the 2D culture cells. Significant increases of total viable cells were found in 3D MCTS groups after drug administration by method of apoptotic analysis. Glucose-lactate analysis indicated that the metabolism of MCTS in CCA scaffold was closer to the tumor issue in vivo than the monolayer cells. In addition, MCTS showed the characteristic of epithelial mesenchymal transition (EMT) which is subverted by carcinoma cells to facilitate metastatic spread. These results demonstrated that MCTS in CCA scaffold possessed a more conservative phenotype of tumor than monolayer cells, and anticancer drug screening in 3D MCTS-CCA system might be superior to the 2D culture system. Copyright © 2016 Elsevier B.V. All rights reserved.
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Boonmars, Thidarut; Wu, Zhiliang; Boonjaruspinyo, Sirintip; Puapairoj, Anucha; Kaewsamut, Butsara; Nagano, Isao; Pinlaor, Somchai; Yongvanit, Puangrat; Wonkchalee, Orasa; Juasook, Amornrat; Sudsarn, Pakkayanee; Srisawangwong, Tuanchai
2011-06-01
Opisthorchiasis is the major public health problem in the endemic areas of Thailand and Laos because Opisthorchis viverrini infection causes serious hepatobiliary diseases including CCA. The molecular mechanism of the CCA carcinogenesis induced by the infection remains obscure. To reveal the potential genes and signaling pathways to involve in the carcinogenesis, the present study investigated the expression of c-Ski, an oncogene, and two TGF-β signaling pathway relative genes, TGF-β and Smad4, during the development of CCA induced by O. viverrini infection in hamster model, and in human opisthorchiasis associated CCA. The results showed that the expression of c-Ski gene was greatly up-regulated during the carcinogenesis of CCA in hamster model. The overexpression of c-Ski was confirmed by immunohistological staining result which showed the increased expression of c-Ski protein in cytoplasm of the epithelial lining of hepatic bile ducts. Moreover, the immunohistological staining of the specimens of human opisthorchiasis associated CCA revealed the up-regulated expression of c-Ski and Smad4 proteins in the cytoplasm of the epithelial lining of hepatic bile ducts and stomal fibrosis respectively. The expression of TGF-β and Smad4 were up-regulated, which expression kinetics was time-dependent of CCA development. These results suggest that c-Ski is likely involved in the carcinogenesis of CCA induced by O. viverrini infection through regulating TGF-β signaling pathway.
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Reappraisal of the Therapeutic Role of Celecoxib in Cholangiocarcinoma
Juang, Horng-Heng; S. Pang, Jong-Hwei; Yu, Chung-Shan; Lin, Kun-Ju; Yeh, Ta-Sen; Jan, Yi-Yin
2013-01-01
Cholangiocarcinoma (CCA), a lethal disease, affects many thousands worldwide yearly. Surgical resection provides the best chance for a cure; however, only one-third of CCA patients present with a resectable tumour at the time of diagnosis. Currently, no effective chemotherapy is available for advanced CCA. Cyclooxygenase-2 (COX-2) is a potential oncogene expressing in human CCA tissues and represents a candidate target for treatment; however, COX-2 inhibitors increase the risk of negative cardiovascular events as application for chemoprevention aim. Here, we re-evaluated the effectiveness and safety of celecoxib, one widely used COX-2 inhibitor, in treating CCA. We demonstrated that celecoxib exhibited an anti-proliferative effect on CGCCA cells via cell cycle arrest at G2 phase and apoptosis induction. Treatment for 5 weeks high dose celecoxib (160 mg/kg) significantly repressed thioacetamide-induced CCA tumour growth in rats as monitored by animal positron emission tomography through apoptosis induction. No obviously observable side effects were noted during the therapeutic period. As retrospectively reviewing 78 intrahepatic mass-forming CCA patients, their survival was strongly and negatively associated with a positive resection margin and high COX-2 expression. Based on our result, we concluded that short-term high dose celecoxib may be a promising therapeutic regimen for CCA. Yet its clinical application still needs more studies to prove its safety. PMID:23922859
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Wang, Sibo; Ren, Zheng; Song, Wenqiao; ...
2015-04-24
Here, a hydrothermal strategy combined with colloidal deposition synthesis was successfully used to grow ZnO/perovskite (LaBO 3, B=Mn, Co, Ni) core-shell nanorod arrays within three dimensional (3-D) honeycomb cordierite substrates. A facile sonication assisted colloidal wash coating process is able to coat a uniformly dispersed perovskite nanoparticles onto the large scale ZnO nanorod arrays rooted on the channel surfaces of the 3D cordierite substrate achieved by hydrothermal synthesis. Compared to traditional wash-coated perovskite catalysts, an enhanced catalytic performance was observed for propane oxidation with 25°C lower light-off temperature than wash-coated perovskite catalyst of similar LaMnO 3 loading (4.3mg). Temperature programmedmore » reduction and desorption under H 2 and O 2 atmosphere, respectively, were used to study the reducibility and oxygen activity of these core-shell nanorod arrays based monolithic catalysts, revealing a catalytic activity sequence of LaCoO 3>LaMnO 3>La 2NiO 4 at the initial stage of catalytic reaction. The good dispersion and size control in La-based perovskite nanoparticles and their interfaces to ZnO nanorod arrays support may contribute to the enhancement of catalytic performance. Lastly, this work may provide a new type of Pt-group metals (PGM) free catalysts with improved catalytic performance for hydrocarbon oxidations at low temperatures.« less
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LEACHING OF CCA-TREATED WOOD: IMPLICATIONS FOR WASTE DISPOSAL
Leaching of arsenic, chromium, and copper from chromated copper arsenate (CCA)-treated wood poses possible environmental risk when disposed. Samples of un-weathered CCA-treated wood were tested using a variety of US regulatory leaching procedures, including the toxicity character...
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Kaewpitoon, Soraya J; Rujirakul, Ratana; Joosiri, Apinya; Jantakate, Sirinun; Sangkudloa, Amnat; Kaewthani, Sarochinee; Chimplee, Kanokporn; Khemplila, Kritsakorn; Kaewpitoon, Natthawut
2016-01-01
Cholangiocarcinoma (CCA) is a serious problem in Thailand, particularly in the northeastern and northern regions. Database of population at risk are need required for monitoring, surveillance, home health care, and home visit. Therefore, this study aimed to develop a geographic information system (GIS) database and Google map of the population at risk of CCA in Mueang Yang district, Nakhon Ratchasima province, northeastern Thailand during June to October 2015. Populations at risk were screened using the Korat CCA verbal screening test (KCVST). Software included Microsoft Excel, ArcGIS, and Google Maps. The secondary data included the point of villages, sub-district boundaries, district boundaries, point of hospital in Mueang Yang district, used for created the spatial databese. The populations at risk for CCA and opisthorchiasis were used to create an arttribute database. Data were tranfered to WGS84 UTM ZONE 48. After the conversion, all of the data were imported into Google Earth using online web pages www.earthpoint.us. Some 222 from a 4,800 population at risk for CCA constituted a high risk group. Geo-visual display available at following www.google.com/maps/d/u/0/ edit?mid=zPxtcHv_iDLo.kvPpxl5mAs90 and hl=th. Geo-visual display 5 layers including: layer 1, village location and number of the population at risk for CCA; layer 2, sub-district health promotion hospital in Mueang Yang district and number of opisthorchiasis; layer 3, sub-district district and the number of population at risk for CCA; layer 4, district hospital and the number of population at risk for CCA and number of opisthorchiasis; and layer 5, district and the number of population at risk for CCA and number of opisthorchiasis. This GIS database and Google map production process is suitable for further monitoring, surveillance, and home health care for CCA sufferers.
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NASA Astrophysics Data System (ADS)
Ritson-Williams, R.; Paul, Valerie J.; Arnold, S. N.; Steneck, R. S.
2010-03-01
The settlement specificity of two threatened Caribbean corals, Acropora palmata and A. cervicornis, was tested by measuring their rates of larval metamorphosis in response to crustose coralline algae (CCA) and other substrata. In the no-choice experiments, the coral larvae were placed in six treatments: filtered seawater (FSW), a fragment of biofilmed dead skeleton of A. palmata, or a fragment of one of four species of CCA ( Hydrolithon boergesenii, Porolithon pachydermum, Paragoniolithon solubile, and Titanoderma prototypum). Within each CCA treatment, there were three different substrata on which to settle and metamorphose: (1) the CCA surface, (2) the rock under the CCA, or (3) the plastic dish. The 5-day-old larvae of both A. palmata and A. cervicornis had similar rates of total metamorphosis (all substrata combined) in every treatment (excluding FSW) even in the absence of CCA. However, there were differences in larval behavior among the CCA species since the larvae settled and metamorphosed on different substrata in the presence of different CCA species. In the no-choice experiments the larvae of both corals had higher rates of metamorphosis on the top surfaces of H. boergesenii and/or T. prototypum than on P. pachydermum. In the choice experiments, the coral larvae were offered two species of CCA in the same dish. When given a choice, both species of coral larvae had more settlement and metamorphosis on the surface of H. boergesenii or T. prototypum or clean rock than onto the surface of P. solubile. After 6 weeks in the field, transplanted A. palmata recruits had approximately 15% survival on both T. prototypum and H. boergesenii, but A. cervicornis recruits only survived on T. prototypum (13%). Some, but not all, CCA species facilitated the larval settlement and post-settlement survival of these two threatened corals, highlighting the importance of benthic community composition for successful coral recruitment.
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NASA Astrophysics Data System (ADS)
Rabiul Islam, Md; Khademul Islam Molla, Md; Nakanishi, Masaki; Tanaka, Toshihisa
2017-04-01
Objective. Recently developed effective methods for detection commands of steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) that need calibration for visual stimuli, which cause more time and fatigue prior to the use, as the number of commands increases. This paper develops a novel unsupervised method based on canonical correlation analysis (CCA) for accurate detection of stimulus frequency. Approach. A novel unsupervised technique termed as binary subband CCA (BsCCA) is implemented in a multiband approach to enhance the frequency recognition performance of SSVEP. In BsCCA, two subbands are used and a CCA-based correlation coefficient is computed for the individual subbands. In addition, a reduced set of artificial reference signals is used to calculate CCA for the second subband. The analyzing SSVEP is decomposed into multiple subband and the BsCCA is implemented for each one. Then, the overall recognition score is determined by a weighted sum of the canonical correlation coefficients obtained from each band. Main results. A 12-class SSVEP dataset (frequency range: 9.25-14.75 Hz with an interval of 0.5 Hz) for ten healthy subjects are used to evaluate the performance of the proposed method. The results suggest that BsCCA significantly improves the performance of SSVEP-based BCI compared to the state-of-the-art methods. The proposed method is an unsupervised approach with averaged information transfer rate (ITR) of 77.04 bits min-1 across 10 subjects. The maximum individual ITR is 107.55 bits min-1 for 12-class SSVEP dataset, whereas, the ITR of 69.29 and 69.44 bits min-1 are achieved with CCA and NCCA respectively. Significance. The statistical test shows that the proposed unsupervised method significantly improves the performance of the SSVEP-based BCI. It can be usable in real world applications.
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Extending local canonical correlation analysis to handle general linear contrasts for FMRI data.
Jin, Mingwu; Nandy, Rajesh; Curran, Tim; Cordes, Dietmar
2012-01-01
Local canonical correlation analysis (CCA) is a multivariate method that has been proposed to more accurately determine activation patterns in fMRI data. In its conventional formulation, CCA has several drawbacks that limit its usefulness in fMRI. A major drawback is that, unlike the general linear model (GLM), a test of general linear contrasts of the temporal regressors has not been incorporated into the CCA formalism. To overcome this drawback, a novel directional test statistic was derived using the equivalence of multivariate multiple regression (MVMR) and CCA. This extension will allow CCA to be used for inference of general linear contrasts in more complicated fMRI designs without reparameterization of the design matrix and without reestimating the CCA solutions for each particular contrast of interest. With the proper constraints on the spatial coefficients of CCA, this test statistic can yield a more powerful test on the inference of evoked brain regional activations from noisy fMRI data than the conventional t-test in the GLM. The quantitative results from simulated and pseudoreal data and activation maps from fMRI data were used to demonstrate the advantage of this novel test statistic.
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Extending Local Canonical Correlation Analysis to Handle General Linear Contrasts for fMRI Data
Jin, Mingwu; Nandy, Rajesh; Curran, Tim; Cordes, Dietmar
2012-01-01
Local canonical correlation analysis (CCA) is a multivariate method that has been proposed to more accurately determine activation patterns in fMRI data. In its conventional formulation, CCA has several drawbacks that limit its usefulness in fMRI. A major drawback is that, unlike the general linear model (GLM), a test of general linear contrasts of the temporal regressors has not been incorporated into the CCA formalism. To overcome this drawback, a novel directional test statistic was derived using the equivalence of multivariate multiple regression (MVMR) and CCA. This extension will allow CCA to be used for inference of general linear contrasts in more complicated fMRI designs without reparameterization of the design matrix and without reestimating the CCA solutions for each particular contrast of interest. With the proper constraints on the spatial coefficients of CCA, this test statistic can yield a more powerful test on the inference of evoked brain regional activations from noisy fMRI data than the conventional t-test in the GLM. The quantitative results from simulated and pseudoreal data and activation maps from fMRI data were used to demonstrate the advantage of this novel test statistic. PMID:22461786
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A review of multivariate methods in brain imaging data fusion
NASA Astrophysics Data System (ADS)
Sui, Jing; Adali, Tülay; Li, Yi-Ou; Yang, Honghui; Calhoun, Vince D.
2010-03-01
On joint analysis of multi-task brain imaging data sets, a variety of multivariate methods have shown their strengths and been applied to achieve different purposes based on their respective assumptions. In this paper, we provide a comprehensive review on optimization assumptions of six data fusion models, including 1) four blind methods: joint independent component analysis (jICA), multimodal canonical correlation analysis (mCCA), CCA on blind source separation (sCCA) and partial least squares (PLS); 2) two semi-blind methods: parallel ICA and coefficient-constrained ICA (CC-ICA). We also propose a novel model for joint blind source separation (BSS) of two datasets using a combination of sCCA and jICA, i.e., 'CCA+ICA', which, compared with other joint BSS methods, can achieve higher decomposition accuracy as well as the correct automatic source link. Applications of the proposed model to real multitask fMRI data are compared to joint ICA and mCCA; CCA+ICA further shows its advantages in capturing both shared and distinct information, differentiating groups, and interpreting duration of illness in schizophrenia patients, hence promising applicability to a wide variety of medical imaging problems.
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Bai, Ling; Mai, Van Cuong; Lim, Yun; Hou, Shuai; Möhwald, Helmuth; Duan, Hongwei
2018-03-01
Structural colors originating from interaction of light with intricately arranged micro-/nanostructures have stimulated considerable interest because of their inherent photostability and energy efficiency. In particular, noniridescent structural color with wide viewing angle has been receiving increasing attention recently. However, no method is yet available for rapid and large-scale fabrication of full-spectrum structural color patterns with wide viewing angles. Here, infiltration-driven nonequilibrium assembly of colloidal particles on liquid-permeable and particle-excluding substrates is demonstrated to direct the particles to form amorphous colloidal arrays (ACAs) within milliseconds. The infiltration-assisted (IFAST) colloidal assembly opens new possibilities for rapid manufacture of noniridescent structural colors of ACAs and straightforward structural color mixing. Full-spectrum noniridescent structural colors are successfully produced by mixing primary structural colors of red, blue, and yellow using a commercial office inkjet printer. Rapid fabrication of large-scale structural color patterns with sophisticated color combination/layout by IFAST printing is realized. The IFAST technology is versatile for developing structural color patterns with wide viewing angles, as colloidal particles, inks, and substrates are flexibly designable for diverse applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Mendes, Manuel J; Hernández, Estela; López, Esther; García-Linares, Pablo; Ramiro, Iñigo; Artacho, Irene; Antolín, Elisa; Tobías, Ignacio; Martí, Antonio; Luque, Antonio
2013-08-30
A colloidal deposition technique is presented to construct long-range ordered hybrid arrays of self-assembled quantum dots and metal nanoparticles. Quantum dots are promising for novel opto-electronic devices but, in most cases, their optical transitions of interest lack sufficient light absorption to provide a significant impact in their implementation. A potential solution is to couple the dots with localized plasmons in metal nanoparticles. The extreme confinement of light in the near-field produced by the nanoparticles can potentially boost the absorption in the quantum dots by up to two orders of magnitude.In this work, light extinction measurements are employed to probe the plasmon resonance of spherical gold nanoparticles in lead sulfide colloidal quantum dots and amorphous silicon thin-films. Mie theory computations are used to analyze the experimental results and determine the absorption enhancement that can be generated by the highly intense near-field produced in the vicinity of the gold nanoparticles at their surface plasmon resonance.The results presented here are of interest for the development of plasmon-enhanced colloidal nanostructured photovoltaic materials, such as colloidal quantum dot intermediate-band solar cells.
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Mogos, Mulubrhan F; Salemi, Jason L; Sultan, Dawood H; Shelton, Melissa M; Salihu, Hamisu M
2015-01-01
Objectives: To estimate the national prevalence of cervical cancer (CCA) in women discharged from hospital after delivery, and to examine its associations with birth outcomes. Methods: We did a retrospective cross-sectional analysis of maternal hospital discharges in the United States (1998-2009). We used the Nationwide Inpatient Sample (NIS) database to identify hospital stays for women who gave birth. We determined length of hospital stay, in-hospital mortality, and used ICD-9-CM codes to identify CCA and all outcomes of interest. Multivariable logistic regression modeling was used to calculate adjusted odds ratios (AOR) and 95% confidence intervals (CI) for the associations between CCA and feto-maternal outcome. Results: In the 12-year period from 1998 to 2009, there were 8,387 delivery hospitalizations with a CCA diagnosis, a prevalence rate of 1.8 per 100,000 (95% CI=1.6, 1.9). After adjusting for potential confounders, CCA was associated with increased odds of maternal morbidities including: anemia (AOR, 1.78, 95% CI, 1.54-2.06), anxiety (AOR, 1.95, 95% CI, 1.11-3.42), cesarean delivery (AOR, 1.67, 95% CI, 1.46-1.90), and prolonged hospital stay (AOR, 1.51, 95% CI, 1.30-1.76), and preterm birth (AOR, 1.69, 95% CI, 1.46-1.97). Conclusion: There is a recent increase in the prevalence of CCA during pregnancy. CCA is associated with severe feto-maternal morbidities. Interventions that promote safer sexual practice and regular screening for CCA should be promoted widely among women of reproductive age to effectively reduce the prevalence of CCA during pregnancy and its impact on the health of mother and baby. PMID:26862361
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Kosriwong, Kanuengnuch; Menheniott, Trevelyan R; Giraud, Andrew S; Jearanaikoon, Patcharee; Sripa, Banchob; Limpaiboon, Temduang
2011-01-01
AIM: To investigate trefoil factor (TFF) gene copy number, mRNA and protein expression as potential biomarkers in cholangiocarcinoma (CCA). METHODS: TFF mRNA levels, gene copy number and protein expression were determined respectively by quantitative reverse transcription polymerase chain reaction (PCR), quantitative PCR and immunohistochemistry in bile duct epithelium biopsies collected from individuals with CCA, precancerous bile duct dysplasia and from disease-free controls. The functional impact of recombinant human (rh)TFF2 peptide treatment on proliferation and epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK) signaling was assessed in the CCA cell line, KMBC, by viable cell counting and immunoblotting, respectively. RESULTS: TFF1, TFF2 and TFF3 mRNA expression was significantly increased in CCA tissue compared to disease-free controls, and was unrelated to gene copy number. TFF1 immunoreactivity was strongly increased in both dysplasia and CCA, whereas TFF2 immunoreactivity was increased only in CCA compared to disease-free controls. By contrast, TFF3 immunoreactivity was moderately decreased in dysplasia and further decreased in CCA. Kaplan-Meier analysis found no association of TFF mRNA, protein and copy number with age, gender, histological subtype, and patient survival time. Treatment of KMBC cells with rhTFF2 stimulated proliferation, triggered phosphorylation of EGFR and downstream extracellular signal related kinase (ERK), whereas co-incubation with the EGFR tyrosine kinase inhibitor, PD153035, blocked rhTFF2-dependent proliferation and EGFR/ERK responses. CONCLUSION: TFF mRNA/protein expression is indicative of CCA tumor progression, but not predictive for histological sub-type or survival time. TFF2 is mitogenic in CCA via EGFR/MAPK activation. PMID:21472131
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Monitoring dominant strictures in primary sclerosing cholangitis with brush cytology and FDG-PET.
Sangfelt, Per; Sundin, Anders; Wanders, Alkwin; Rasmussen, Ib; Karlson, Britt-Marie; Bergquist, Annika; Rorsman, Fredrik
2014-12-01
Despite a high risk of cholangiocellular adenocarcinoma (CCA) it is unclear how surveillance of patients with primary sclerosing cholangitis (PSC) should be performed. We evaluated a follow-up algorithm of brush cytology and positron emission tomography/computed tomography with [(18)F] fluorodeoxyglucose ([(18)F]FDG-PET/CT), measured as maximum standardized uptake values, normalized to the liver background (SUVmax/liver) at 180 min, in PSC patients with dominant bile duct strictures. Brush cytology with high grade dysplasia (HGD) was detected in 12/70 patients (17%), yielding a diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 56%, 89%, 75%, and 88%, respectively. Preemptive liver transplantations due to repeated HGD before manifest CCA were performed in six patients. Receiver operating characteristic (ROC) analysis of [(18)F]FDG uptake showed that a SUVmax/liver quotient of 3.3 was able to discriminate between CCA and non-malignant disease with a sensitivity, specificity, PPV and NPV for CCA of 89%, 92%, 62%, 98%, respectively. A SUVmax/liver >3.3 detected CCA in 8/9 patients whereas a quotient <2.4 excluded CCA. Combining brush cytology and quantitative [(18)F]FDG-PET/CT yielded a sensitivity for HGD and/or CCA of 100% and a specificity of 88%. Early detection of HGD before manifest CCA is feasible with repeated brush cytology and may allow for preemptive liver transplantation. [(18)F]FDG-PET/CT has a high sensitivity for manifest CCA and a negative scan indicates a non-malignant state of the disease. Brush cytology and [(18)F]FDG-PET/CT are complementary in monitoring and managing PSC patients with dominant strictures. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
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Evaluation of Strength Characteristics of Laterized Concrete with Corn Cob Ash (CCA) Blended Cement
NASA Astrophysics Data System (ADS)
Ikponmwosa, E. E.; Salau, M. A.; Kaigama, W. B.
2015-11-01
Agricultural wastes are dumped in landfills or left on land in which they constitute nuisance. This study presents the results of investigation of strength characteristics of reinforced laterized concrete beams with cement partially replaced with corn cob (agricultural wastes) ash (CCA). Laterized concrete specimen of 25% laterite and 75% sharp sand were made by blending cement with corn cob ash at 0 to 40% in steps of 10%. A concrete mix ratio of 1:2:4 was used to cast 54 cubes of 150×150×150mm size and 54 beams of dimension 750×150×150mm. The results show that the consistency and setting time of cement increased as the percentage replacement of cement with CCA increased while the workability and density of concrete decreased as the percentage of CCA increased. There was a decrease in compressive strength when laterite was introduced to the concrete from 25.04 to 22.96N/mm2 after 28 days and a continual reduction in strength when CCA was further added from 10% to 40% at steps of 10%. Generally, the beam specimens exhibited majorly shear failure with visible diagonal cracks extending from support points to the load points. The corresponding central deflection in beams, due to two points loading, increased as the laterite was added to the concrete mix but reduced and almost approaching that of the control as 10% CCA was added. The deflection then increased as the CCA content further increased to 20%, 30% and 40% in the mix. It was also noted that the deflection of all percentage replacement including 40% CCA is less than the standard recommended maximum deflection of the beam. The optimal flexural strength occurred with 10% CCA content.
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NASA Astrophysics Data System (ADS)
Chen, Yi-Feng; Atal, Kiran; Xie, Sheng-Quan; Liu, Quan
2017-08-01
Objective. Accurate and efficient detection of steady-state visual evoked potentials (SSVEP) in electroencephalogram (EEG) is essential for the related brain-computer interface (BCI) applications. Approach. Although the canonical correlation analysis (CCA) has been applied extensively and successfully to SSVEP recognition, the spontaneous EEG activities and artifacts that often occur during data recording can deteriorate the recognition performance. Therefore, it is meaningful to extract a few frequency sub-bands of interest to avoid or reduce the influence of unrelated brain activity and artifacts. This paper presents an improved method to detect the frequency component associated with SSVEP using multivariate empirical mode decomposition (MEMD) and CCA (MEMD-CCA). EEG signals from nine healthy volunteers were recorded to evaluate the performance of the proposed method for SSVEP recognition. Main results. We compared our method with CCA and temporally local multivariate synchronization index (TMSI). The results suggest that the MEMD-CCA achieved significantly higher accuracy in contrast to standard CCA and TMSI. It gave the improvements of 1.34%, 3.11%, 3.33%, 10.45%, 15.78%, 18.45%, 15.00% and 14.22% on average over CCA at time windows from 0.5 s to 5 s and 0.55%, 1.56%, 7.78%, 14.67%, 13.67%, 7.33% and 7.78% over TMSI from 0.75 s to 5 s. The method outperformed the filter-based decomposition (FB), empirical mode decomposition (EMD) and wavelet decomposition (WT) based CCA for SSVEP recognition. Significance. The results demonstrate the ability of our proposed MEMD-CCA to improve the performance of SSVEP-based BCI.
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Huebner, H J; Mayura, K; Pallaroni, L; Ake, C L; Lemke, S L; Herrera, P; Phillips, T D
2000-01-01
Patulin, a heterocyclic lactone produced by various species of Penicillium and Aspergillus fungi, is often detected in apple juices and ciders. Previous research has shown the effectiveness of granular activated carbon for reducing patulin levels in aqueous solutions, apple juices, and ciders. In this study, ultrafine activated carbon was bonded onto granular quartz to produce a composite carbon adsorbent (CCA) with a high carbonaceous surface area, good bed porosity, and increased bulk density. CCA in fixed-bed adsorption columns was evaluated for efficacy in reducing patulin levels from aqueous solutions and apple juice. Columns containing 1.0, 0.5, and 0.25 g of CCA were continuously loaded with a patulin solution (10 microg/ml) and eluted at a flow rate of 1 ml/min. Results indicated that 50% breakthrough capacities for patulin on 1.0-, 0.5-, and 0.25-g CCA columns were 137.5, 38.5, and 19.9 microg, respectively. The effectiveness of CCA to adsorb patulin and prevent toxic effects was confirmed in vitro using adult hydra in culture. Hydra were sensitive to the effects of patulin, with a minimal affective concentration equal to 0.7 microg/ml; CCA adsorption prevented patulin toxicity until 76% breakthrough capacity was achieved. Fixed-bed adsorption with 1.0 g of CCA was also effective in reducing patulin concentrations (20 microg/liter) in a naturally contaminated apple juice, and breakthrough capacities were shown to increase with temperature. Additionally, CCA offered a higher initial breakthrough capacity than pelleted activated carbon when compared in parallel experiments. This study suggests that CCA used in fixed-bed adsorption systems effectively reduced patulin levels in both aqueous solutions and naturally contaminated apple juice; however, the appearance and taste of apple juice may be affected by the treatment process.
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Rubaba, O; Chimbari, M J; Soko, W; Manyangadze, T; Mukaratirwa, S
2018-06-01
Circulating cathodic antigen (CCA) tests for schistosomiasis are fast and less complicated allowing making them good candidates for routine qualitative screening for schistosomiasis at point of care. The urine-CCA has been evaluated for detection of S. mansoni with promising results. Its specificity and consistency in detecting S. haematobium infection in different endemic regions has been variable. This study validated a rapid urine-CCA cassette test for qualitative detection of S. haematobium infection in an S. haematobium endemic area with low S. mansoni prevalence. Microscopic examination for the standard urine filtration technique was used to validate the commercially available urine-CCA cassette test (rapid medical diagnostics ® ). The validation was done in a sample of primary school pupils (n = 420) aged 10-15 years in schools in the Jozini Municipality, KZN. There was a relationship between infection intensity and a positive urine-CCA test. Using the urine filtration method as the gold standard, the prevalence for S. haematobium was 40%, the accuracy of the CCA kit was 54.8%, sensitivity was 68.1% while the specificity was 45.8%. The positive predictive value was 45.82% while the negative predictive value was 68.05%. Both the urine filtration and the urine-CCA methods detected heavy (≥50 eggs/10 mL urine) and light infections at statistically significant levels. The overall accuracy, sensitivity and specificity of the urine-CCA cassette test were low. The urine-CCA cassette test performed much better for heavy infections than low infections (p < 0.05) implying that the kit may not be suitable for low endemic areas. Copyright © 2018 Elsevier B.V. All rights reserved.
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Martus, Peter; Laule, Michael; Dewey, Marc; Schönenberger, Eva
2015-01-01
Objectives To evaluate how well patients with coronary stents accept combined coronary computed tomography angiography (CTA) and myocardial CT perfusion (CTP) compared with conventional coronary angiography (CCA). Background While combined CTA and CTP may improve diagnostic accuracy compared with CTA alone, patient acceptance of CTA/CTP remains to be defined. Methods A total of 90 patients with coronary stents prospectively underwent CTA/CTP (both with contrast agent, CTP with adenosine) and CCA as part of the CARS-320 study. In this group, an intraindividual comparison of patient acceptance of CTA, CTP, and CCA was performed. Results CTP was experienced to be significantly more painful than CTA (p<0.001) and was associated with a higher frequency of dyspnea (p<0.001). Comparison of CTA/CTP with CCA revealed no significant differences in terms of pain (p = 0.141) and comfort (p = 0.377). Concern before CTA/CTP and CCA and overall satisfaction were likewise not significantly different (p = 0.097 and p = 0.123, respectively). Nevertheless, about two thirds (n = 60, 68%) preferred CTA/CTP to CCA (p<0.001). Moreover, patients felt less helpless during CTA/CTP than during CCA (p = 0.026). Lack of invasiveness and absence of pain were the most frequently mentioned advantages of CTA/CTP over CCA in our patient population. Conclusions CCA and combined CTA/CTP are equally well accepted by patients; however, more patients prefer CTA/CTP. CTP was associated with more intense pain than CTA and more frequently caused dyspnea than CTA alone. Trial Registration ClinicalTrials.gov NCT00967876 PMID:26327127
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kopach, V. R.; Klepikova, K. S.; Klochko, N. P., E-mail: klochko-np@mail.ru
We investigate the structure, surface morphology, and optical properties of nanostructured ZnO arrays fabricated by pulsed electrodeposition, Ag nanoparticles precipitated from colloidal solutions, and a ZnO/Ag nanocomposite based on them. The electronic and electrical parameters of the ZnO arrays and ZnO/Ag nanocomposites are analyzed by studying the I–V and C–V characteristics. Optimal modes for fabricating the ZnO/Ag heterostructures with the high stability and sensitivity to ultraviolet radiation as promising materials for use in photodetectors, gas sensors, and photocatalysts are determined.
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Superhydrophobic Analyte Concentration Utilizing Colloid-Pillar Array SERS Substrates
Wallace, Ryan A.; Charlton, Jennifer J.; Kirchner, Teresa B.; ...
2014-11-04
In order to detect a few molecules present in a large sample it is important to know the trace components in the medicinal and environmental sample. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. Moreover, the following work involves superhydrophobic surfaces that includes silicon pillar arrays formed by lithographic and dewetting protocols. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added tomore » the functionalized pillar array system via soaking. The pillars are used native and with hydrophobic modification. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 10-12 M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up applications in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.« less
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Superhydrophobic Analyte Concentration Utilizing Colloid-Pillar Array SERS Substrates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wallace, Ryan A.; Charlton, Jennifer J.; Kirchner, Teresa B.
In order to detect a few molecules present in a large sample it is important to know the trace components in the medicinal and environmental sample. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. Moreover, the following work involves superhydrophobic surfaces that includes silicon pillar arrays formed by lithographic and dewetting protocols. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added tomore » the functionalized pillar array system via soaking. The pillars are used native and with hydrophobic modification. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 10-12 M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up applications in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.« less
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Benslimane, A F; Pouchus, Y F; Verbist, J F; Petit, J Y; Khettab, E N; Welin, L; Brion, J D
1992-01-01
A new synthesis is proposed for cordiachromene A (CCA), a bioactive component of the ascidian Aplidium antillense Gravier, using a method producing a racemic mixture. The anti-inflammatory activities of a natural extract and a chemically synthetic form of CCA were assessed in vivo by carrageenan-induced rat-paw edema. The activity of synthetic CCA was confirmed by a test on kaolin-induced granuloma in the rat. Strong activities were measured for both CCA, but comparison of results of the first test suggests that only the natural optically active isomer has an anti-inflammatory effect. CCA is similar to indomethacin in its effect on carrageenan-induced rat-paw edema and ten times as active as phenylbutazone.
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NASA Astrophysics Data System (ADS)
Islas, María S.; Martínez Medina, Juan J.; Piro, Oscar E.; Echeverría, Gustavo A.; Ferrer, Evelina G.; Williams, Patricia A. M.
2018-06-01
Coumarins (2H-chromen-2-one) are oxygen-containing heterocyclic compounds that belong to the benzopyranones family. In this work we have synthesized different coordination complexes with coumarin-3-carboxylic acid (HCCA), o-phenanthroline (phen) and zinc(II). In the reported [Zn(CCA)2(H2O)2] complex, coumarin-3-carboxylate (CCA) is acting as a bidentate ligand while in the two prepared complexes, [Zn(phen)3]CCA(NO3) (obtained as a single crystal) and [Zn(CCA)2phen].4H2O, CCA is acting as a counterion of the complex cation [Zn(phen)3]+2 or coordinated to the metal center along with phen, respectively. These compounds were characterized on the basis of elemental analysis and thermogravimetry. NMR, FTIR and Raman spectroscopies of the compounds and the CCA potassium salt (KCCA) allow to determine several similarities and differences among them. Finally, their behavior against alkaline phosphatase enzyme and their antimicrobial activities were also measured.
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Kamya, Pamela Z; Byrne, Maria; Mos, Benjamin; Hall, Lauren; Dworjanyn, Symon A
2017-06-14
The indirect effects of changing climate in modulating trophic interactions can be as important as the direct effects of climate stressors on consumers. The success of the herbivorous juvenile stage of the crown-of-thorns starfish (COTS), Acanthaster planci, may be affected by the impacts of ocean conditions on its crustose coralline algal (CCA) food. To partition the direct effects of near future ocean acidification on juvenile COTS and indirect effects through changes in their CCA food, COTS were grown in three pH T levels (7.9, 7.8, 7.6) and fed CCA grown at similar pH levels. Consumption of CCA by COTS was bolstered when the COTS were grown in low pH and when they were fed CCA grown in low pH regardless of the pH in which the COTS were reared. COTS fed CCA grown at pH 7.6 grew fastest, but the pH/ p CO 2 that the COTS were reared in had no direct effect on growth. Ocean acidification conditions decreased the C : N ratio and carbonate levels in the CCA. Bolstered growth in COTS may be driven by enhanced palatability, increased nutritive state and reduced defences of their CCA food. These results indicate that near future acidification will increase the success of early juvenile COTS and boost recruitment into the coral-eating life stage. © 2017 The Author(s).
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Tunable TiO2 Nanotube Arrays for Flexible Bio-Sensitized Solar Cells
2012-08-01
microid extender followed by a colloidal silica /wetted imperial cloth. The foil was then cut into 1- × 2-cm samples. Then, the substrates were...17. Lei, B.; Liao, J.; Wang, R. J.; Su, C.; Kuang, D. Ordered Crystalline Ti02 Nanotube Arrays on Transparent FTO Glass for Efficient Dye...combined with a transparent , Indium Tin Dioxide coated PET film are attractive candidates for efficient, flexible DSSC’s. Flexible solar cells offer
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Self-assembled biomimetic antireflection coatings
NASA Astrophysics Data System (ADS)
Linn, Nicholas C.; Sun, Chih-Hung; Jiang, Peng; Jiang, Bin
2007-09-01
The authors report a simple self-assembly technique for fabricating antireflection coatings that mimic antireflective moth eyes. Wafer-scale, nonclose-packed colloidal crystals with remarkable large hexagonal domains are created by a spin-coating technology. The resulting polymer-embedded colloidal crystals exhibit highly ordered surface modulation and can be used directly as templates to cast poly(dimethylsiloxane) (PDMS) molds. Moth-eye antireflection coatings with adjustable reflectivity can then be molded against the PDMS master. The specular reflection of replicated nipple arrays matches the theoretical prediction using a thin-film multilayer model. These biomimetic films may find important technological application in optical coatings and solar cells.
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Smart photonic coating as a new visualization technique of strain deformation of metal plates
NASA Astrophysics Data System (ADS)
Fudouzi, Hiroshi; Sawada, Tsutomu; Tanaka, Yoshikazu; Ario, Ichiro; Hyakutake, Tsuyoshi; Nishizaki, Itaru
2012-04-01
We will present a simple and low cost method to visualize local strain distribution in deformed aluminum plates. In this study, aluminum plates were coated with opal photonic crystal film with tunable structural color. The photonic crystal films consist of a silicone elastomer that contains an array of submicron polystyrene colloidal particles. When the aluminum sheets were stretched, the change in the spacing of the colloidal particles in the opal film alters the color of the film. This approach could be useful as a new strain gauge having a visual indicator to detect mechanical deformation.
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Reusing remediated CCA-treated wood
Carol A. Clausen
2003-01-01
Options for recycling and reusing chromated-copper-arsenate- (CCA) treated material include dimensional lumber and round wood size reduction, composites, and remediation. Size reduction by remilling, shaving, or resawing CCA-treated wood reduces the volume of landfilled waste material and provides many options for reusing used treated wood. Manufacturing composite...
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Concerns have been raised regarding the safety of young children contacting arsenic and chromium residues while playing on and around Chromated Copper Arsenate (CCA) treated wood playground structures and decks. Although CCA registrants voluntarily canceled treated wood for re...
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Clements, Michelle N; Corstjens, Paul L A M; Binder, Sue; Campbell, Carl H; de Dood, Claudia J; Fenwick, Alan; Harrison, Wendy; Kayugi, Donatien; King, Charles H; Kornelis, Dieuwke; Ndayishimiye, Onesime; Ortu, Giuseppina; Lamine, Mariama Sani; Zivieri, Antonio; Colley, Daniel G; van Dam, Govert J
2018-02-23
Kato-Katz examination of stool smears is the field-standard method for detecting Schistosoma mansoni infection. However, Kato-Katz misses many active infections, especially of light intensity. Point-of-care circulating cathodic antigen (CCA) is an alternative field diagnostic that is more sensitive than Kato-Katz when intensity is low, but interpretation of CCA-trace results is unclear. To evaluate trace results, we tested urine and stool specimens from 398 pupils from eight schools in Burundi using four approaches: two in Burundi and two in a laboratory in Leiden, the Netherlands. In Burundi, we used Kato-Katz and point-of-care CCA (CCAB). In Leiden, we repeated the CCA (CCAL) and also used Up-Converting Phosphor Circulating Anodic Antigen (CAA). We applied Bayesian latent class analyses (LCA), first considering CCA traces as negative and then as positive. We used the LCA output to estimate validity of the prevalence estimates of each test in comparison to the population-level infection prevalence and estimated the proportion of trace results that were likely true positives. Kato-Katz yielded the lowest prevalence (6.8%), and CCAB with trace considered positive yielded the highest (53.5%). There were many more trace results recorded by CCA in Burundi (32.4%) than in Leiden (2.3%). Estimated prevalence with CAA was 46.5%. LCA indicated that Kato-Katz had the lowest sensitivity: 15.9% [Bayesian Credible Interval (BCI): 9.2-23.5%] with CCA-trace considered negative and 15.0% with trace as positive (BCI: 9.6-21.4%), implying that Kato-Katz missed approximately 85% of infections. CCAB underestimated disease prevalence when trace was considered negative and overestimated disease prevalence when trace was considered positive, by approximately 12 percentage points each way, and CAA overestimated prevalence in both models. Our results suggest that approximately 52.2% (BCI: 37.8-5.8%) of the CCAB trace readings were true infections. Whether measured in the laboratory or the field, CCA outperformed Kato-Katz at the low infection intensities in Burundi. CCA with trace as negative likely missed many infections, whereas CCA with trace as positive overestimated prevalence. In the absence of a field-friendly gold standard diagnostic, the use of a variety of diagnostics with differing properties will become increasingly important as programs move towards elimination of schistosomiasis. It is clear that CCA is a valuable tool for the detection and mapping of S. mansoni infection in the field and CAA may be a valuable field tool in the future.
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Alternatives to chromated copper arsenate for residential construction
Stan T. Lebow
2004-01-01
For decades chromated copper arsenate (CCA) was the primary preservative for treated wood used in residential construction. However, recent label changes submitted by CCA registrants will withdraw CCA from most residential applications. This action has increased interest in arsenic free preservative systems that have been standardized by the American Wood Preservers...
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What's stopping the recycling of recovered CCA-treated lumber
R. Smith; D. Alderman; Philip A. Araman
2002-01-01
The awareness and concerns regarding the environmental impacts and disposal of chromated copper arsenate (CCA) treated wood products are increasing. Several investigators predict that the quantities of CCA-treated lumber will increase significantly in the upcoming decades. Additionally, with the number of landfills decreasing, landfill tipping fees increasing, and...
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NASA Astrophysics Data System (ADS)
Fu, Chit Yaw; U. S., Dinish; Rautela, Shashi; Goh, Douglas Wenda; Olivo, Malini
2011-12-01
Gold-coated array patterned with tightly-packed nanospheres was developed as a substrate base for constructing SERSenriched nanogaps with Au-nanoparticles (GNPs). Using 1,2-ethanedithiol as a linker, Au-NPs (=17-40nm) were anchored covalently on the sphere-array. Thin Au layer was sputtered on the substrate to mask the citrate coating of GNPs that could demote the sensing mechanism. The negatively-charged GNP surface warrants the colloidal stability, but the resulting repulsive force keeps the immobilized NPs apart by about 40nm. The attained gap size is inadequately narrow to sustain any intense enhancement owing to the near-field nature of SERS. Minimal amount of NaCl was then added to slightly perturb the colloidal stability by reducing their surface charge. Notably, the interparticle-gap reduces at increasing amount of salt, giving rise to increased packing density of GNPs. The SERS enhancement is also found to exponentially increase at decreasing gap size. Nevertheless, the minimum gap achieved is limited to merely 7nm. Excessive addition of salt would eventually induce complete aggregation of particles, forming clustered NPs on the array. A simple sputtering-growth approach is therefore proposed to further minimize the interparticle gap by enlarging the seeded NPs based on mild sputtering. The SEM images confirm that the gap below 7nm is achievable. With advent of the colloidal chemistry, the combined salt-induced aggregation and sputtering-growth techniques can be applied to engineer interparticle gap that is crucial to realize an ultrasensitive SERS biosensor. The proposed two-step preparation can be potentially adopted to fabricate the SERS-enriched nanogaps on the microfluidics platform.
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Advances in endoscopic retrograde cholangiopancreatography for the treatment of cholangiocarcinoma
Uppal, Dushant S; Wang, Andrew Y
2015-01-01
Cholangiocarcinoma (CCA) is a malignancy of the bile ducts that carries high morbidity and mortality. Patients with CCA typically present with obstructive jaundice, and associated complications of CCA include cholangitis and biliary sepsis. Endoscopic retrograde cholangiopancreatography (ERCP) is a valuable treatment modality for patients with CCA, as it enables internal drainage of blocked bile ducts and hepatic segments by using plastic or metal stents. While there remains debate as to if bilateral (or multi-segmental) hepatic drainage is required and/or superior to unilateral drainage, the underlying tenant of draining any persistently opacified bile ducts is paramount to good ERCP practice and good clinical outcomes. Endoscopic therapy for malignant biliary strictures from CCA has advanced to include ablative therapies via ERCP-directed photodynamic therapy (PDT) or radiofrequency ablation (RFA). While ERCP techniques cannot cure CCA, advancements in the field of ERCP have enabled us to improve upon the quality of life of patients with inoperable and incurable disease. ERCP-directed PDT has been used in lieu of brachytherapy to provide neoadjuvant local tumor control in patients with CCA who are awaiting liver transplantation. Lastly, mounting evidence suggests that palliative ERCP-directed PDT, and probably ERCP-directed RFA as well, offer a survival advantage to patients with this difficult-to-treat malignancy. PMID:26140095
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Advances in endoscopic retrograde cholangiopancreatography for the treatment of cholangiocarcinoma.
Uppal, Dushant S; Wang, Andrew Y
2015-06-25
Cholangiocarcinoma (CCA) is a malignancy of the bile ducts that carries high morbidity and mortality. Patients with CCA typically present with obstructive jaundice, and associated complications of CCA include cholangitis and biliary sepsis. Endoscopic retrograde cholangiopancreatography (ERCP) is a valuable treatment modality for patients with CCA, as it enables internal drainage of blocked bile ducts and hepatic segments by using plastic or metal stents. While there remains debate as to if bilateral (or multi-segmental) hepatic drainage is required and/or superior to unilateral drainage, the underlying tenant of draining any persistently opacified bile ducts is paramount to good ERCP practice and good clinical outcomes. Endoscopic therapy for malignant biliary strictures from CCA has advanced to include ablative therapies via ERCP-directed photodynamic therapy (PDT) or radiofrequency ablation (RFA). While ERCP techniques cannot cure CCA, advancements in the field of ERCP have enabled us to improve upon the quality of life of patients with inoperable and incurable disease. ERCP-directed PDT has been used in lieu of brachytherapy to provide neoadjuvant local tumor control in patients with CCA who are awaiting liver transplantation. Lastly, mounting evidence suggests that palliative ERCP-directed PDT, and probably ERCP-directed RFA as well, offer a survival advantage to patients with this difficult-to-treat malignancy.
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Songthamwat, Metha; Chamadol, Nittaya; Khuntikeo, Narong; Thinkhamrop, Jadsada; Koonmee, Supinda; Chaichaya, Nathaphop; Bethony, Jeffrey; Thinkhamrop, Bandit
2017-09-20
Treatment planning especially liver resection in cholangiocarcinoma (CCA) depends on the extension of tumor and lymph node metastasis which is included as a key criterion for operability. Magnetic resonance imaging (MRI) offers a rapid and powerful tool for the detection of lymph node metastasis (LNM) and in the current manuscript is assessed as a critical tool in the preoperative protocol for liver resection for treatment of CCA. However, the accuracy of MRI to detect LNM from CCA had yet to be comprehensively evaluated. The accuracy of MRI to detect LNM was assessed in a cohort of individuals with CCA from the Cholangiocarcinoma Screening and Care Program (CASCAP), a screening program designed to reduce CCA in Northeastern Thailand by community-based ultrasound (US) for CCA. CCA-positive individuals are referred to one of the nine tertiary centers in the study to undergo a preoperative protocol that included enhanced imaging by MRI. Additionally, these individuals also underwent lymph node biopsies for histological confirmation of LNM (the "gold standard") to determine the accuracy of the MRI results. MRI accurately detected the presence or absence of LNM in only 29 out of the 51 CCA cases (56.9%, 95% CI 42.2-70.7), resulting in a sensitivity of 57.1% (95% CI 34.0-78.2) and specificity of 56.7% (95% CI 37.4-74.5), with positive and negative predictive values of 48.0% (95% CI 27.8-68.7) and 65.4% (95% CI 44.3-82.8), respectively. The positive likelihood ratio was 1.32 (95% CI 0.76-2.29), and the negative likelihood ratio was 0.76 (95% CI 0.42-1.36). MRI showed limited sensitivity and a poor positive predictive value for the diagnosis of LNM for CCA, which is of particular concern in this resource-limited setting, where simpler detection methods could be utilized that are more cost-effective in this region of Thailand. Therefore, the inclusion of MRI, a costly imaging method, should be reconsidered as part of protocol for treatment planning of CCA, given the number of false positives, especially as it is critical in determining the operability for CCA subjects.
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Islam, Rakibul M; Bell, Robin J; Billah, Baki; Hossain, Mohammad B; Davis, Susan R
2015-12-01
Cervical cancer (CCa) is the second most common cancer among women in Bangladesh. The uptake of CCa screening was less than 10% in areas where screening has been offered, so we investigated the awareness of CCa and CCa screening, and factors associated with women's preparedness to be screened. A nationally representative, cross-sectional survey of women aged 30-59 years was conducted in 7 districts of the 7 divisions in Bangladesh, using a multistage cluster sampling technique. Factors associated with the awareness of CCa and screening uptake were investigated separately, using multivariable logistic regression. On systematic questioning, 81.3% and 48.6% of the 1,590 participants, whose mean age was 42.3 (±8.0) years, had ever heard of CCa and CCa screening, respectively. Having heard of CCa was associated with living in a rural area (adjusted odds ratio [OR]: 0.42; 95% confidence interval [CI]: 0.26-0.67), being 40-49 years old (OR: 1.59; 95% CI: 1.15-2.0), having no education (OR: 0.25; 95% CI: 0.16-0.38), and being obese (OR: 2.04; 95% CI: 1.23-3.36). Of the 773 women who had ever heard of CCa screening, 86% reported that they had not been screened because they had no symptoms and 37% did not know screening was needed. Only 8.3% had ever been screened. Having been screened was associated with being 40-49 years old (OR: 2.17; 95% CI: 1.19-3.94) and employed outside the home (OR: 3.83; 95% CI: 1.65-8.9), and inversely associated with rural dwelling (OR: 0.54; 95% CI: 0.30-0.98) and having no education (OR: 0.29; 95% CI: 0.10-0.85). Lack of awareness of CCa and of understanding of the concept of screening are the key barriers to screening uptake in women at midlife in Bangladesh. Targeted educational health programs are needed to increase screening in Bangladesh with the view to reducing mortality. ©AlphaMed Press.
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Steele, Jennifer A; Richter, Carsten H; Echaubard, Pierre; Saenna, Parichat; Stout, Virginia; Sithithaworn, Paiboon; Wilcox, Bruce A
2018-05-17
Cholangiocarcinoma (CCA) is a fatal bile duct cancer associated with infection by the liver fluke, Opisthorchis viverrini, in the lower Mekong region. Numerous public health interventions have focused on reducing exposure to O. viverrini, but incidence of CCA in the region remains high. While this may indicate the inefficacy of public health interventions due to complex social and cultural factors, it may further indicate other risk factors or interactions with the parasite are important in pathogenesis of CCA. This systematic review aims to provide a comprehensive analysis of described risk factors for CCA in addition to O. viverrini to guide future integrative interventions. We searched five international and seven Thai research databases to identify studies relevant to risk factors for CCA in the lower Mekong region. Selected studies were assessed for risk of bias and quality in terms of study design, population, CCA diagnostic methods, and statistical methods. The final 18 included studies reported numerous risk factors which were grouped into behaviors, socioeconomics, diet, genetics, gender, immune response, other infections, and treatment for O. viverrini. Seventeen risk factors were reported by two or more studies and were assessed with random effects models during meta-analysis. This meta-analysis indicates that the combination of alcohol and smoking (OR = 11.1, 95% CI: 5.63-21.92, P < 0.0001) is most significantly associated with increased risk for CCA and is an even greater risk factor than O. viverrini exposure. This analysis also suggests that family history of cancer, consumption of raw cyprinoid fish, consumption of high nitrate foods, and praziquantel treatment are associated with significantly increased risk. These risk factors may have complex relationships with the host, parasite, or pathogenesis of CCA, and many of these risk factors were found to interact with each other in one or more studies. Our findings suggest that a complex variety of risk factors in addition to O. viverrini infection should be addressed in future public health interventions to reduce CCA in affected regions. In particular, smoking and alcohol use, dietary patterns, and socioeconomic factors should be considered when developing intervention programs to reduce CCA.
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Ocean acidification reduces induction of coral settlement by crustose coralline algae.
Webster, Nicole S; Uthicke, Sven; Botté, Emanuelle S; Flores, Florita; Negri, Andrew P
2013-01-01
Crustose coralline algae (CCA) are a critical component of coral reefs as they accrete carbonate for reef structure and act as settlement substrata for many invertebrates including corals. CCA host a diversity of microorganisms that can also play a role in coral settlement and metamorphosis processes. Although the sensitivity of CCA to ocean acidification (OA) is well established, the response of their associated microbial communities to reduced pH and increased CO2 was previously not known. Here we investigate the sensitivity of CCA-associated microbial biofilms to OA and determine whether or not OA adversely affects the ability of CCA to induce coral larval metamorphosis. We experimentally exposed the CCA Hydrolithon onkodes to four pH/pCO2 conditions consistent with current IPCC predictions for the next few centuries (pH: 8.1, 7.9, 7.7, 7.5, pCO2 : 464, 822, 1187, 1638 μatm). Settlement and metamorphosis of coral larvae was reduced on CCA pre-exposed to pH 7.7 (pCO2 = 1187 μatm) and below over a 6-week period. Additional experiments demonstrated that low pH treatments did not directly affect the ability of larvae to settle, but instead most likely altered the biochemistry of the CCA or its microbial associates. Detailed microbial community analysis of the CCA revealed diverse bacterial assemblages that altered significantly between pH 8.1 (pCO2 = 464 μatm) and pH 7.9 (pCO2 = 822 μatm) with this trend continuing at lower pH/higher pCO2 treatments. The shift in microbial community composition primarily comprised changes in the abundance of the dominant microbes between the different pH treatments and the appearance of new (but rare) microbes at pH 7.5. Microbial shifts and the concomitant reduced ability of CCA to induce coral settlement under OA conditions projected to occur by 2100 is a significant concern for the development, maintenance and recovery of reefs globally. © 2012 Blackwell Publishing Ltd.
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Uddin, Md. Hafiz; Choi, Min-Ho; Kim, Woo Ho; Jang, Ja-June; Hong, Sung-Tae
2015-01-01
Background Clonorchis sinensis is a group-I bio-carcinogen for cholangiocarcinoma (CCA). Although the epidemiological evidence links clonorchiasis and CCA, the underlying molecular mechanism involved in this process is poorly understood. In the present study, we investigated expression of oncogenes and tumor suppressors, including PSMD10, CDK4, p53 and RB in C. sinensis induced hamster CCA model. Methods Different histochemical/immunohistochemical techniques were performed to detect CCA in 4 groups of hamsters: uninfected control (Ctrl.), infected with C. sinensis (Cs), ingested N-nitrosodimethylamine (NDMA), and both Cs infected and NDMA introduced (Cs+NDMA). The liver tissues from all groups were analyzed for gene/protein expressions by quantitative PCR (qPCR) and western blotting. Principal Findings CCA was observed in all hamsters of Cs+NDMA group with well, moderate, and poorly differentiated types measured in 21.8% ± 1.5%, 13.3% ± 1.3%, and 10.8% ± 1.3% of total tissue section areas respectively. All CCA differentiations progressed in a time dependent manner, starting from the 8th week of infection. CCA stroma was characterized with increased collagen type I, mucin, and proliferative cell nuclear antigen (PCNA). The qPCR analysis showed PSMD10, CDK4 and p16INK4 were over-expressed, whereas p53 was under-expressed in the Cs+NDMA group. We observed no change in RB1 at mRNA level but found significant down-regulation of RB protein. The apoptosis related genes, BAX and caspase 9 were found downregulated in the CCA tissue. Gene/protein expressions were matched well with the pathological changes of different groups except the NDMA group. Though the hamsters in the NDMA group showed no marked pathological lesions, we observed over-expression of Akt/PKB and p53 genes proposing molecular interplay in this group which might be related to the CCA initiation in this animal model. Conclusions/Significance The present findings suggest that oncogenes, PSMD10 and CDK4, and tumor suppressors, p53 and RB, are involved in the carcinogenesis process of C. sinensis induced CCA in hamsters. PMID:26313366
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Crustose coralline algae and associated microbial biofilms deter seaweed settlement on coral reefs
NASA Astrophysics Data System (ADS)
Gomez-Lemos, Luis A.; Diaz-Pulido, Guillermo
2017-06-01
Crustose coralline algae (CCA), a group of calcifying red algae found commonly in benthic marine ecosystems worldwide, perform essential ecological functions on coral reefs, including creating benthic substrate, stabilizing the reef structure and inducing coral settlement. An important feature of CCA is the ability to keep their surfaces free of epiphytic algae, thereby reducing algal overgrowth and allowing them access to light. However, the mechanisms by which CCA prevent settlement of opportunistic seaweeds (fleshy macroalgae) are not fully understood, nor is whether these mechanisms vary among CCA species. In our study based on the Great Barrier Reef, we demonstrate that three common CCA species ( Titanoderma pustulatum, Porolithon onkodes and Neogoniolithon sp.) have a remarkable ability to deter settlement of seaweed spores. We provide experimental evidence that the CCA use allelopathy and microbial inhibition against the settlement of spores of the brown seaweed Padina boergesenii. Methanol extracts of allelopathic compounds from T. pustulatum, Po. onkodes and Neogoniolithon sp. significantly reduced the settlement of Pa. boergesenii spores by 4.3 times, 3.0 and 3.8 times, respectively. Further, we found that microbial biofilms, while having a lower inhibitory effect than allelopathic compounds, also reduced seaweed settlement of Pa. boergesenii. Our study demonstrates that allelopathy and microbial inhibition, in addition to epithallial tissue sloughing, are mechanisms employed by CCA to prevent the settlement of epiphytic algae. Understanding the mechanisms by which CCA avoid seaweed overgrowth contributes to our understanding of the dynamics of seaweed proliferations on reefs and to the ecological knowledge of this important group of reef-building organisms.
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NASA Astrophysics Data System (ADS)
Chen, Kai; Duy Dao, Thang; Nagao, Tadaaki
2017-03-01
We fabricated large-area metallic (Al and Au) nanoantenna arrays on Si substrates using cost-effective colloidal lithography with different micrometer-sized polystyrene spheres. Variation of the sphere size leads to tunable plasmon resonances in the middle infrared (MIR) range. The enhanced near-fields allow us to detect the surface phonon polaritons in the natural SiO2 thin layers. We demonstrated further tuning capability of the resonances by employing dry etching of the Si substrates with the nanoantennas acting as the etching masks. The effective refractive index of the nanoantenna surroundings is efficiently decreased giving rise to blueshifts of the resonances. In addition, partial removal of the Si substrates elevates the nanoantennas from the high-refractive-index substrates making more enhanced near-fields accessible for molecular sensing applications as demonstrated here with surface-enhanced infrared absorption (SEIRA) spectroscopy for a thin polymer film. We also directly compared the plasmonic enhancement from the Al and Au nanoantenna arrays.
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Transparent arrays of silver nanowire rings driven by evaporation of sessile droplets
NASA Astrophysics Data System (ADS)
Wang, Xiaofeng; Kang, Giho; Seong, Baekhoon; Chae, Illkyeong; Teguh Yudistira, Hadi; Lee, Hyungdong; Kim, Hyunggun; Byun, Doyoung
2017-11-01
A coffee-ring pattern can be yielded on the three-phase contact line following evaporation of sessile droplets with suspended insoluble solutes, such as particles, DNA molecules, and mammalian cells. The formation of such coffee-ring, together with their suppression has been applied in printing and coating technologies. We present here an experimental study on the assembly of silver nanowires inside an evaporating droplet of a colloidal suspension. The effects of nanowire length and concentration on coffee-ring formation of the colloidal suspension were investigated. Several sizes of NWs with an aspect ratio between 50 and 1000 were systematically investigated to fabricate coffee-ring patterns. Larger droplets containing shorter nanowires formed clearer ring deposits after evaporation. An order-to-disorder transition of the nanowires’ alignment was found inside the rings. A printing technique with the evaporation process enabled fabrication of arrays of silver nanowire rings. We could manipulate the patterns silver nanowire rings, which might be applied to the transparent and flexible electrode.
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Scaled-up remediation of CCA-treated wood
Carol A. Clausen; William R. Kenealy
2004-01-01
Bioremediation is a novel approach to recycling waste wood treated with chromated copper arsenate (CCA). Remediating CCA-treated waste wood diverts this fiber source from our landfills and provides tangible secondary products from the cleaned fiber. On a laboratory scale, this method, which utilizes oxalic acid extraction and bioleaching with a metal- tolerant...
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Cai, Jia; Tang, Yi
2018-02-01
Canonical correlation analysis (CCA) is a powerful statistical tool for detecting the linear relationship between two sets of multivariate variables. Kernel generalization of it, namely, kernel CCA is proposed to describe nonlinear relationship between two variables. Although kernel CCA can achieve dimensionality reduction results for high-dimensional data feature selection problem, it also yields the so called over-fitting phenomenon. In this paper, we consider a new kernel CCA algorithm via randomized Kaczmarz method. The main contributions of the paper are: (1) A new kernel CCA algorithm is developed, (2) theoretical convergence of the proposed algorithm is addressed by means of scaled condition number, (3) a lower bound which addresses the minimum number of iterations is presented. We test on both synthetic dataset and several real-world datasets in cross-language document retrieval and content-based image retrieval to demonstrate the effectiveness of the proposed algorithm. Numerical results imply the performance and efficiency of the new algorithm, which is competitive with several state-of-the-art kernel CCA methods. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Applications of temporal kernel canonical correlation analysis in adherence studies.
John, Majnu; Lencz, Todd; Ferbinteanu, Janina; Gallego, Juan A; Robinson, Delbert G
2017-10-01
Adherence to medication is often measured as a continuous outcome but analyzed as a dichotomous outcome due to lack of appropriate tools. In this paper, we illustrate the use of the temporal kernel canonical correlation analysis (tkCCA) as a method to analyze adherence measurements and symptom levels on a continuous scale. The tkCCA is a novel method developed for studying the relationship between neural signals and hemodynamic response detected by functional MRI during spontaneous activity. Although the tkCCA is a powerful tool, it has not been utilized outside the application that it was originally developed for. In this paper, we simulate time series of symptoms and adherence levels for patients with a hypothetical brain disorder and show how the tkCCA can be used to understand the relationship between them. We also examine, via simulations, the behavior of the tkCCA under various missing value mechanisms and imputation methods. Finally, we apply the tkCCA to a real data example of psychotic symptoms and adherence levels obtained from a study based on subjects with a first episode of schizophrenia, schizophreniform or schizoaffective disorder.
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Zhao, Xiaofang; Zhang, Chunyan; Zhou, Hong; Xiao, Bin; Cheng, Ying; Wang, Jinju; Yao, Fuli; Duan, Chunyan; Chen, Run; Liu, Youping; Feng, Chunhong; Li, Hong; Li, Jing; Dai, Rongyang
2016-12-20
Less is known about the roles of eukaryotic initiation factor alpha (eIF2α) in cholangiocarcinoma (CCA). Here, we report that eIF2α inhibitor salubrinal inhibits the proliferation of human CCA cells. Clinical application of mammalian target of rapamycin (mTOR) inhibitors only has moderate antitumor efficacy. Therefore, combination approaches may be required for effective clinical use of mTOR inhibitors. Here, we investigated the efficacy of the combination of salubrinal and rapamycin in the treatment of CCA. Our data demonstrate a synergistic antitumor effect of the combination of salubrinal and rapamycin against CCA cells. Rapamycin significantly inhibits the proliferation of CCA cells. However, rapamycin initiates a negative feedback activation of Akt. Inhibition of Akt by salubrinal potentiates the efficacy of rapamycin both in vitro and in vivo. Additionally, rapamycin treatment results in the up-regulation of Bcl-xL in a xenograft mouse model. It is notable that salubrinal inhibits rapamycin-induced Bcl-xL up-regulation in vivo. Taken together, our data suggest that salubrinal and rapamycin combination might be a new and effective strategy for the treatment of CCA.
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Molecular profiling of intrahepatic cholangiocarcinoma: the search for new therapeutic targets.
Oliveira, Douglas V N P; Zhang, Shanshan; Chen, Xin; Calvisi, Diego F; Andersen, Jesper B
2017-04-01
Intrahepatic cholangiocarcinoma (iCCA) is the second most frequent primary tumor of the liver and a highly lethal disease. Therapeutic options for advanced iCCA are limited and ineffective due to the largely incomplete understanding of the molecular pathogenesis of this deadly tumor. Areas covered: The present review article outlines the main studies and resulting discoveries on the molecular profiling of iCCA, with a special emphasis on the different techniques used for this purpose, the diagnostic and prognostic markers identified, as well as the genes and pathways that could be potentially targeted with innovative therapies. Expert commentary: Molecular profiling has led to the identification of distinct iCCA subtypes, characterized by peculiar genetic alterations and transcriptomic features. Targeted therapies against some of the identified genes are ongoing and hold great promise to improve the prognosis of iCCA patients.
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Su, Si-Biao; Zhang, Jian-Feng; Huang, Fei-Fei; Cen, Yu; Jiang, Hai-Xing
2017-08-01
Cholangiocarcinoma (CCA) associated with liver fluke infection involves inflammatory and immune processes; however, whether these involve the proinflammatory cytokine IL-17A and proliferative cytokine IL-22 remains unclear. Here, numbers of IL-22- and IL-17A-producing Th cells and cytokine concentrations in 30 patients with CCA and long-term liver fluke infection, 40 patients with liver-fluke infection but not CCA, and 16 healthy controls were compared. Analyses were performed using immunohistochemistry, flow cytometry, ELISA and RT-PCR. Immunohistochemical staining showed weaker expression of IL-22 and IL-17A in patients with CCA with than in those without liver fluke infection (P < 0.01). Flow cytometry revealed significantly greater median proportions of IL-22-producing T helper cells in patients with CCA (2.2%) than in those without it (0.69%) or controls (0.4%, P < 0.001). Similar results were obtained for IL-17A-producing T helper cells. ELISA revealed plasma concentrations of IL-22 were 1.3-fold higher in patients with CCA than in those without it and 4.6-fold higher than in controls (P < 0.001). Plasma concentrations of IL-17A were 2.5-fold higher in patients with CCA than in those without it, and 21-fold higher than in controls (P < 0.001). Amounts of IL-22 and IL-17A mRNAs in blood were significantly higher in patients with CCA than in the other two groups. Proportions of CD4 + CD45RO + T cells producing IL-22 correlated with proportions producing IL-17A (r = 0.759; P < 0.001), and plasma concentrations of IL-22 correlated with those of IL-17A (r = 0.726; P < 0.001). These results suggest that both IL-17A and IL-22 affect development of CCA related to liver fluke infection. © 2017 The Societies and John Wiley & Sons Australia, Ltd.
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Clements, Michelle N; Donnelly, Christl A; Fenwick, Alan; Kabatereine, Narcis B; Knowles, Sarah C L; Meité, Aboulaye; N'Goran, Eliézer K; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E; Tukahebwa, Edridah Muheki; Fleming, Fiona M
2017-12-01
The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous 'trace' result between 'positive' and 'negative', and much debate has focused on interpretation of traces results. We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d'Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence.
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Donnelly, Christl A.; Fenwick, Alan; Kabatereine, Narcis B.; Knowles, Sarah C. L.; Meité, Aboulaye; N'Goran, Eliézer K.; Nalule, Yolisa; Nogaro, Sarah; Phillips, Anna E.; Tukahebwa, Edridah Muheki; Fleming, Fiona M.
2017-01-01
Background The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous ‘trace’ result between ‘positive’ and ‘negative’, and much debate has focused on interpretation of traces results. Methodology/Principle findings We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both Côte d’Ivoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Conclusions Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence. PMID:29220354
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Yang, Heping; Liu, Ting; Wang, Jiaohong; Li, Tony W.H.; Fan, Wei; Peng, Hui; Krishnan, Anuradha; Gores, Gregory J.; Mato, Jose M.; Lu, Shelly C.
2016-01-01
We reported c-Myc induction drives cholestatic liver injury and cholangiocarcinoma (CCA) in mice. We also showed induction of Maf proteins (MafG and c-Maf) contributed to cholestatic liver injury, whereas S-adenosylmethionine (SAMe) administration was protective. Here we determined whether there is interplay between c-Myc, Maf proteins and methionine adenosyltransferase α1 (MATα1), which is responsible for SAMe biosynthesis in liver. We used bile duct ligation (BDL) and lithocholic acid (LCA) treatment in mice as chronic cholestasis models, a murine CCA model, human CCA cell lines KMCH and Huh-28, human liver cancer HepG2, and human CCA specimens to study gene and protein expression, protein-protein interactions, molecular mechanisms and functional outcomes. We found c-Myc, MATα1 (encoded by MAT1A), MafG and c-Maf interact with each other directly. MAT1A expression fell in hepatocytes and bile duct epithelial cells during chronic cholestasis and in murine and human CCA. The opposite occurred with c-Myc, MafG and c-Maf expression. MATα1 interacts mainly with Mnt in normal liver but this switches to c-Maf, MafG and c-Myc in cholestatic livers and CCA. Promoter regions of these genes have E-boxes that are bound by MATα1 and Mnt in normal liver and benign bile duct epithelial cells that switched to c-Myc, c-Maf and MafG in cholestasis and CCA cells. E-box positively regulates c-Myc, MafG and c-Maf, but it negatively regulates MAT1A. MATα1 represses whereas c-Myc, MafG and c-Maf enhance E-box-driven promoter activity. Knocking down MAT1A or overexpressing MafG or c-Maf enhanced CCA growth and invasion in vivo. Conclusion We have uncovered a novel interplay between MATα1, c-Myc and Maf proteins and their deregulation during chronic cholestasis may facilitate CCA oncogenesis. PMID:26969892
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Stimulak, Mitja; Ravnik, Miha
2014-09-07
Blue phase colloidal crystals and dielectric nanoparticle/polymer doped blue phases are demonstrated to combine multiple components with different symmetries in one photonic material, creating a photonic crystal with variable and micro-controllable photonic band structure. In this composite photonic material, one contribution to the band structure is determined by the 3D periodic birefringent orientational profile of the blue phases, whereas the second contribution emerges from the regular array of the colloidal particles or from the dielectric/nanoparticle-doped defect network. Using the planewave expansion method, optical photonic bands of the blue phase I and II colloidal crystals and related nanoparticle/polymer doped blue phases are calculated, and then compared to blue phases with no particles and to face-centred-cubic and body-centred-cubic colloidal crystals in isotropic background. We find opening of local band gaps at particular points of Brillouin zone for blue phase colloidal crystals, where there were none in blue phases without particles or dopants. Particle size and filling fraction of the blue phase defect network are demonstrated as parameters that can directly tune the optical bands and local band gaps. In the blue phase I colloidal crystal with an additionally doped defect network, interestingly, we find an indirect total band gap (with the exception of one point) at the entire edge of SC irreducible zone. Finally, this work demonstrates the role of combining multiple - by symmetry - differently organised components in one photonic crystal material, which offers a novel approach towards tunable soft matter photonic materials.
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Absent right common carotid artery associated with aberrant right subclavian artery.
Uchino, Akira; Uwabe, Kazuhiko; Osawa, Iichiro
2018-06-01
Rarely, the external and internal carotid arteries arise separately from the brachiocephalic trunk and right subclavian artery (SA) or the aortic arch and reflect the absence of a common carotid artery (CCA). We report a 45-year-old man with absent right CCA associated with aberrant right SA, an extremely rare combination, diagnosed by computed tomography (CT) angiography during follow-up for postoperative aortic dissection. Retrospective careful observation of preoperative postcontrast CT revealed the absent right CCA. Previously reported arch variations associated with absent CCA include cervical aortic arch, double aortic arch, and right aortic arch.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Ray, Hasi
2006-06-15
The best three-channel projectile-inelastic close-coupling approximation (CCA) is used to study the resonances in positronium (Ps) and hydrogen (H) scattering at the energy region below the inelastic threshold. The s-wave elastic phase shifts and s-wave elastic cross sections are studied using the static-exchange, two- and three-channel projectile-inelastic CCA for both the singlet (+) and triplet (-) channels. The singlet resonances detected using different CCA schemes confirm previous predictions [Drachman and Houston, Phys. Rev. A 12, 885 (1975); Page, J. Phys. B. 9, 1111 (1976)]. We report a resonance in the triplet channel too using the present three-channel CCA scheme.
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Large-area, near-infrared (IR) photonic crystals with colloidal gold nanoparticles embedding.
Shukla, Shobha; Baev, Alexander; Jee, Hongsub; Hu, Rui; Burzynski, Ryszard; Yoon, Yong-Kyu; Prasad, Paras N
2010-04-01
A polymeric composite material composed of colloidal gold nanoparticles (<10 nm) and SU8 has been utilized for the fabrication of large-area, high-definition photonic crystal. We have successfully fabricated near-infrared photonic crystal slabs from composite materials using a combination of multiple beam interference lithography and reactive ion etching processes. Doping of colloidal gold nanoparticles into the SU8 photopolymer results in a better definition of structural features and hence in the enhancement of the optical properties of the fabricated photonic crystals. A 2D air hole array of triangular symmetry with a hole-to-hole pitch of approximately 500 nm has been successfully fabricated in a large circular area of 1 cm diameter. Resonant features observed in reflectance spectra of our slabs are found to depend on the exposure time, and can be tuned over a range of near-infrared frequencies.
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Doped colloidal artificial spin ice
Libál, A.; Reichhardt, C. J. Olson; Reichhardt, C.
2015-10-07
We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Conversely, magnetic artificial spin ices, unlike colloidal and vortex artificial spin ice realizations, allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is raised. In contrast, the kagome ice ground state can absorb the doping charge without generating non-ground-state excitations, while at elevated temperatures the hopping of individual colloidsmore » is suppressed near the doping sites. Our results indicate that in the square ice, doping adds degeneracy to the ordered ground state and creates local weak spots, while in the kagome ice, which has a highly degenerate ground state, doping locally decreases the degeneracy and creates local hard regions.« less
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Doped colloidal artificial spin ice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Libál, A.; Reichhardt, C. J. Olson; Reichhardt, C.
We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Conversely, magnetic artificial spin ices, unlike colloidal and vortex artificial spin ice realizations, allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is raised. In contrast, the kagome ice ground state can absorb the doping charge without generating non-ground-state excitations, while at elevated temperatures the hopping of individual colloidsmore » is suppressed near the doping sites. Our results indicate that in the square ice, doping adds degeneracy to the ordered ground state and creates local weak spots, while in the kagome ice, which has a highly degenerate ground state, doping locally decreases the degeneracy and creates local hard regions.« less
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NASA Astrophysics Data System (ADS)
Fu, Yanan; Xie, Honglan; Deng, Biao; Du, Guohao; Xiao, Tiqiao
2017-06-01
The floatage self-assembly method was introduced with mixed solvent as the medium of polystyrene sphere suspension to fabricate the colloidal crystal. The three dimensional (3D) void system of the colloidal crystal was noninvasively characterized by synchrotron radiation phase-contrast computed tomography, and the quantitative image analysis was implemented aiming to the polystyrene sphere colloidal crystal. Comparing with gravity sedimentation method, the three samples fabricated from floatage self-assembly with mixed solvents have the lowest porosity, and when ethylene glycol and water were mixed with ratio of 1:1, the lowest porosity of 27.49% could be achieved, that has been very close to the minimum porosity of ordered 3D monodisperse sphere array (26%). In single slices, the porosities and fractal dimension for the voids were calculated. The results showed that two factors would significantly influence the porosity of the whole colloidal crystal: the first deposited sphere layer's orderliness and the sedimentation speed of the spheres. The floatage self-assembly could induce a stable close-packing process, resulted from the powerful nucleation force-lateral capillary force coupled with the mixed solvent to regulate the floating upward speed for purpose of matching the assembly rate.
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Yin, Da-long; Liang, Ying-jian; Zheng, Tong-sen; Song, Rui-peng; Wang, Jia-bei; Sun, Bo-shi; Pan, Shang-ha; Qu, Lian-dong; Liu, Jia-ren; Jiang, Hong-chi; Liu, Lian-xin
2016-01-01
A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment. PMID:27571770
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Yin, Da-Long; Liang, Ying-Jian; Zheng, Tong-Sen; Song, Rui-Peng; Wang, Jia-Bei; Sun, Bo-Shi; Pan, Shang-Ha; Qu, Lian-Dong; Liu, Jia-Ren; Jiang, Hong-Chi; Liu, Lian-Xin
2016-08-30
A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment.
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EPA is approximately 20 months into a project to evaluate the performance of wood coatings as a way to prevent arsenic, chromium and copper exposure from the surfaces of CCA treated wood. Potential dermal exposure, as measured by wipe sampling dislodgeable CCA chemical from wood ...
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Chromated copper arsenate (CCA) treated wood is a preservative treated wood construction product that grew in use in the 1970s for both residential and industrial applications. In the U.S. CCA-treated wood is disposed primarily within landfills, however some of the wood is combu...
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How much arsenic is released when CCA wood is burned?
Charles K. McMahon; Parshall B. Bush; Edwin A. Woolson
1986-01-01
Abstract. Waterborne salts have been used to preserve wood for many years. One of the more common formulations contains copper, chromium, and arsenic salts and is known as chromated copper arsenate, or CCA. Questions have been raised about the amount of arsenic released when CCA treated wood is burned in wood stoves, fireplaces, or boilers....
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Properties of particleboard made from recycled CCA-treated wood
Carol A. Clausen; S. Nami Kartal; James Muehl
2000-01-01
Recovery of chromated copper arsenate (CCA)-treated wood for reuse has been the focus of several international research groups due to the imminent disposal problem created when large quantities of CCA-treated wood ultimately come out of service. Bioleaching with Bacillus licheniformis CC01 and oxalic acid extraction are two methods known to remove significant...
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ERIC Educational Resources Information Center
Whitehouse, Andrew J. O.; Coon, Hilary; Miller, Judith; Salisbury, Bryanna; Bishop, Dorothy V. M.
2010-01-01
This study investigated whether the Communication Checklist-Adult (CC-A) could identify subtypes of social and communication dysfunction in autism probands and their parents. The CC-A is divided into subscales measuring linguistic ability as well as two aspects of social communication: the Pragmatic Skills subscale assesses the level of pragmatic…
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From a contractors perspective: what is needed to recover used CCA treated lumber?
Delton R. Alderman; Robert L. Smith; Philip A. Araman
2003-01-01
The rationale of this research was to discern the factors that currently are preventing contractors from recovering and recycling spent chromated copper arsenate (CCA) lumber. This study examines the effects of evaluations and beliefs, subjective norms, perceived behavioral control, and awareness of the contractor's decision intention to recover used CCA lumber....
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Delton Alderman; Robert Smith; Philip A. Araman
2003-01-01
This research developed a profile of used chromated copper arsenate (CCA) lumber removed from the demolition of residential decking. This was achieved by gathering and compiling information regarding the construction, demolition, deck remodeling, deck replacement factors, and factors affecting the recovery of spent CCA lumber. In addition, qualitative responses...
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Nonlinear multivariate and time series analysis by neural network methods
NASA Astrophysics Data System (ADS)
Hsieh, William W.
2004-03-01
Methods in multivariate statistical analysis are essential for working with large amounts of geophysical data, data from observational arrays, from satellites, or from numerical model output. In classical multivariate statistical analysis, there is a hierarchy of methods, starting with linear regression at the base, followed by principal component analysis (PCA) and finally canonical correlation analysis (CCA). A multivariate time series method, the singular spectrum analysis (SSA), has been a fruitful extension of the PCA technique. The common drawback of these classical methods is that only linear structures can be correctly extracted from the data. Since the late 1980s, neural network methods have become popular for performing nonlinear regression and classification. More recently, neural network methods have been extended to perform nonlinear PCA (NLPCA), nonlinear CCA (NLCCA), and nonlinear SSA (NLSSA). This paper presents a unified view of the NLPCA, NLCCA, and NLSSA techniques and their applications to various data sets of the atmosphere and the ocean (especially for the El Niño-Southern Oscillation and the stratospheric quasi-biennial oscillation). These data sets reveal that the linear methods are often too simplistic to describe real-world systems, with a tendency to scatter a single oscillatory phenomenon into numerous unphysical modes or higher harmonics, which can be largely alleviated in the new nonlinear paradigm.
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Kozakova, Michaela; Natali, Andrea; Dekker, Jacqueline; Beck-Nielsen, Henning; Laakso, Markku; Nilsson, Peter; Balkau, Beverley; Ferrannini, Ele
2013-06-01
Despite a wealth of experimental data in animal models, the independent association of insulin resistance with early carotid atherosclerosis in man has not been demonstrated. We studied a European cohort of 525 men and 655 women (mean age, 44 ± 8 years) free of conditions known to affect carotid wall (diabetes mellitus, hypertension, and dyslipidemia). All subjects received an oral glucose tolerance test, a euglycemic hyperinsulinemic clamp (M/I as a measure of insulin sensitivity), and B-mode carotid ultrasound. In 833 participants (380 men), the carotid ultrasound was repeated after 3 years. In men, baseline intima-media thickness in the common carotid artery (CCA-IMT) was significantly higher (P<0.05) in the lowest M/I tertile, whereas in women CCA-IMT was higher (P<0.0005) in the highest fasting plasma glucose tertile (after adjustment for established risk factors). In multiple regression models, with CCA-IMT as the dependent variable and with risk factors and univariate metabolic correlates as independent variables, circulating free fatty acids and the leptin:adiponectin ratio replaced M/I as independent metabolic determinants of CCA-IMT in men. The strongest metabolic determinant of CCA-IMT in women was fasting plasma glucose. Three-year CCA-IMT changes were not associated with any cardio-metabolic risk factor. In young-to-middle aged apparently healthy people, the association of CCA-IMT with insulin sensitivity and its metabolic correlates differs between men and women. Lower insulin sensitivity is associated with higher IMT only in men; this association seems to be mediated by circulating free fatty acids and adipocytokines. In women, CCA-IMT is independently associated with fasting plasma glucose.
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Rivera, Claudia
2014-01-01
This paper analyses the perceptions of disaster risk reduction (DRR) practitioners concerning the on-going integration of climate change adaptation (CCA) into their practices in urban contexts in Nicaragua. Understanding their perceptions is important as this will provide information on how this integration can be improved. Exploring the perceptions of practitioners in Nicaragua is important as the country has a long history of disasters, and practitioners have been developing the current DRR planning framework for more than a decade. The analysis is based on semi-structured interviews designed to collect information about practitioners’ understanding of: (a) CCA, (b) the current level of integration of CCA into DRR and urban planning, (c) the opportunities and constraints of this integration, and (d) the potential to adapt cities to climate change. The results revealed that practitioners’ perception is that the integration of CCA into their practice is at an early stage, and that they need to improve their understanding of CCA in terms of a development issue. Three main constraints on improved integration were identified: (a) a recognized lack of understanding of CCA, (b) insufficient guidance on how to integrate it, and (c) the limited opportunities to integrate it into urban planning due to a lack of instruments and capacity in this field. Three opportunities were also identified: (a) practitioners’ awareness of the need to integrate CCA into their practices, (b) the robust structure of the DRR planning framework in the country, which provides a suitable channel for facilitating integration, and (c) the fact that CCA is receiving more attention and financial and technical support from the international community. PMID:24475365
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Surapaitoon, Arpa; Suttiprapa, Sutas; Mairiang, Eimorn; Khuntikeo, Narong; Pairojkul, Chawalit; Bethony, Jeffrey; Brindley, Paul J; Sripa, Banchob
2017-06-01
Opisthorchis viverrini infection induces chronic inflammation, and a minor proportion of infected individuals develop advanced periductal fibrosis (APF) and cholangiocarcinoma (CCA). Inflammatory cytokines and/or their gene polymorphisms may link to these biliary pathologies. We therefore investigated associations among cytokine gene polymorphisms and cytokine production in 510 Thai cases infected with O. viverrini who presented with APF+ or APF-, as established by abdominal ultrasonography as well as in patients diagnosed with CCA. Levels of pro-inflammatory and anti-inflammatory cytokines were determined in culture supernatants after stimulation of peripheral blood mononuclear cells (PBMCs) with O. viverrini excretory-secretory (ES) products. Pro-inflammatory cytokines, IL-1β, IL-6, IFN-γ, LT-α, and TNF-α were significantly increased in CCA patients compared with non-CCA (APF- and APF+) cases. Polymorphisms in genes encoding IL-1β-511C/T, IL-6-174G/C, IFN-γ +874T/A, LT-α +252A/G, and TNF-α -308G/A were then investigated by using PCR-RFLP or allele specific-PCR (AS-PCR) analyses. In the CCA cases, LT-α +252A/G and TNF-α -308G/A heterozygous and homozygous variants showed significantly higher levels of these cytokines than the wild type. By contrast, levels of cytokines in wild type of IFN-γ +874T/A were significantly higher than the variants in CCA cases. IFN-γ +874T/A polymorphisms were associated with advanced periductal fibrosis, whereas IL-6 -174G/C polymorphisms were associated with CCA. To our knowledge, these findings provide the first demonstration that O. viverrini infected individuals carrying several specific cytokine gene polymorphisms are susceptible to develop fibrosis and CCA.
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Surapaitoon, Arpa; Suttiprapa, Sutas; Mairiang, Eimorn; Khuntikeo, Narong; Pairojkul, Chawalit; Bethony, Jeffrey; Brindley, Paul J.; Sripa, Banchob
2017-01-01
Opisthorchis viverrini infection induces chronic inflammation, and a minor proportion of infected individuals develop advanced periductal fibrosis (APF) and cholangiocarcinoma (CCA). Inflammatory cytokines and/or their gene polymorphisms may link to these biliary pathologies. We therefore investigated associations among cytokine gene polymorphisms and cytokine production in 510 Thai cases infected with O. viverrini who presented with APF+ or APF−, as established by abdominal ultrasonography as well as in patients diagnosed with CCA. Levels of pro-inflammatory and anti-inflammatory cytokines were determined in culture supernatants after stimulation of peripheral blood mononuclear cells (PBMCs) with O. viverrini excretory-secretory (ES) products. Pro-inflammatory cytokines, IL-1β, IL-6, IFN-γ, LT-α, and TNF-α were significantly increased in CCA patients compared with non-CCA (APF− and APF+) cases. Polymorphisms in genes encoding IL-1β-511C/T, IL-6-174G/C, IFN-γ +874T/A, LT-α +252A/G, and TNF-α −308G/A were then investigated by using PCR-RFLP or allele specific-PCR (AS-PCR) analyses. In the CCA cases, LT-α +252A/G and TNF-α −308G/A heterozygous and homozygous variants showed significantly higher levels of these cytokines than the wild type. By contrast, levels of cytokines in wild type of IFN-γ +874T/A were significantly higher than the variants in CCA cases. IFN-γ +874T/A polymorphisms were associated with advanced periductal fibrosis, whereas IL-6 −174G/C polymorphisms were associated with CCA. To our knowledge, these findings provide the first demonstration that O. viverrini infected individuals carrying several specific cytokine gene polymorphisms are susceptible to develop fibrosis and CCA. PMID:28719954
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Suksawat, Manida; Techasen, Anchalee; Namwat, Nisana; Yongvanit, Puangrat; Khuntikeo, Narong; Titapun, Attapon; Koonmee, Supinda; Loilome, Watcharin
2017-08-01
Endothelial nitric oxide synthase (eNOS) is an isoform of the enzyme nitric oxide synthase (NOS) which is constitutively expressed in endothelial cells and plays important roles in vasodilation. We previously reported the importance of eNOS activation in cholangiocarcinoma (CCA) tissues and cell lines. The present study aims to investigate the relative abundance of eNOS and phosphorylated eNOS (P-eNOS) and their upstream regulators VEGFR3, VEGFC, EphA3 and ephrin-A1, in the Opisthorchis viverrini (Ov)/N-nitrosodimethylamine (NDMA)-induced hamster CCA model and in human CCA by semiquantitative immunohistochemical analysis of the relevant tissues. Results from the hamster model suggested an increase in eNOS and P-eNOS and upstream regulators during CCA genesis. In human CCA, high immunohistochemical staining intensity of all investigated proteins was associated with the presence of metastasis. A pairwise analysis of the staining data for eNOS and its upstream regulators showed that a concurrent increase in eNOS/VEGFR3, eNOS/ephrin-A1, eNOS/VEGFC and eNOS/EphA3 was significantly associated with metastasis. An increase in eNOS/VEGFR3, eNOS/ephrin-A1 was also associated with non-papillary type CCA. Additionally, an increase in eNOS and P-eNOS was significantly correlated with a high micro-vessel level (P=0.04). Our results indicate that the development of CCA involves upregulation of eNOS and P-eNOS and their regulators. This may drive angiogenesis and metastasis in CCA. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
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Ortu, Giuseppina; Ndayishimiye, Onésime; Clements, Michelle; Kayugi, Donatien; Campbell, Carl H.; Lamine, Mariama Sani; Zivieri, Antonio; Magalhaes, Ricardo Soares; Binder, Sue; King, Charles H.; Fenwick, Alan; Colley, Daniel G.; Jourdan, Peter Mark
2017-01-01
Following implementation of the national control program, a reassessment of Schistosoma mansoni prevalence was conducted in Burundi to determine the feasibility of moving toward elimination. A countrywide cluster-randomized cross-sectional study was performed in May 2014. At least 25 schools were sampled from each of five eco-epidemiological risk zones for schistosomiasis. Fifty randomly selected children 13–14 years of age per school were included for a single urine-circulating cathodic antigen (CCA) rapid test and, in a subset of schools, for duplicate Kato-Katz slide preparation from a single stool sample. A total of 17,331 children from 347 schools were tested using CCA. The overall prevalence of S. mansoni infection, when CCA trace results were considered negative, was 13.5% (zone range [zr] = 4.6–17.8%), and when CCA trace results were considered positive, it was 42.8% (zr = 34.3–49.9%). In 170 schools, prevalence of this infection determined using Kato-Katz method was 1.5% (zr ==0–2.7%). The overall mean intensity of S. mansoni infection determined using Kato-Katz was 0.85 eggs per gram (standard deviation = 10.86). A majority of schools (84%) were classified as non-endemic (prevalence = 0) using Kato-Katz; however, a similar proportion of schools were classified as endemic when CCA trace results were considered negative (85%) and nearly all (98%) were endemic when CCA trace results were considered positive. The findings of this nationwide reassessment using a CCA rapid test indicate that Schistosoma infection is still widespread in Burundi, although its average intensity is probably low. Further evidence is now needed to determine the association between CCA rapid test positivity and low-intensity disease transmission. PMID:28115675
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An on-chip colloidal magneto-optical grating
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prikockis, M.; Wijesinghe, H.; Chen, A.
2016-04-18
Interacting nano- and micro-particles provide opportunities to create a wide range of useful colloidal and soft matter constructs. In this letter, we examine interacting superparamagnetic polymeric particles residing on designed permalloy (Ni{sub 0.8} Fe{sub 0.2}) shapes that are subject to weak time-orbiting magnetic fields. The precessing field and magnetic barriers that ensue along the outer perimeter of the shapes allow for containment concurrent with independent field-tunable ordering of the dipole-coupled particles. These remotely activated arrays with inter-particle spacing comparable to the wavelength of light yield microscopic on-chip surface gratings for beam steering and magnetically regulated light diffraction applications.
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Dynamic colloidal sorting on a magnetic bubble lattice
NASA Astrophysics Data System (ADS)
Tierno, Pietro; Soba, Alejandro; Johansen, Tom H.; Sagués, Francesc
2008-11-01
We use a uniaxial garnet film with a magnetic bubble lattice to sort paramagnetic colloidal particles with different diameters, i.e., 1.0 and 2.8μm. We apply an external magnetic field which precesses around an axis normal to the film with a frequency Ω =62.8s-1 and intensity 3120A/m
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Superhydrophobic analyte concentration utilizing colloid-pillar array SERS substrates.
Wallace, Ryan A; Charlton, Jennifer J; Kirchner, Teresa B; Lavrik, Nickolay V; Datskos, Panos G; Sepaniak, Michael J
2014-12-02
The ability to detect a few molecules present in a large sample is of great interest for the detection of trace components in both medicinal and environmental samples. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. The following work involves superhydrophobic surfaces that have as a framework deterministic or stochastic silicon pillar arrays formed by lithographic or metal dewetting protocols, respectively. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added to the functionalized pillar array system via soaking. Native pillars and pillars with hydrophobic modification are used. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A ≥ 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 × 10(-12) M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up uses in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.
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Bin Yu; Chung Y. Hse; Todd F. Shupe
2009-01-01
The effects of acid concentration, reaction time, and temperature in a microwave reactor on recovery of CCA-treated wood were evaluated. Extraction of copper, chromium, and arsenic metals from chromated copper arsenate (CCA)-treated southern pine wood samples with three different acids (i.e., acetic acid, oxalic acid, and phosphoric acid) was investigated using in...
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Semi-solid state bioremediation of CCA-treated wood using malted barley as a nutrient source
Carol A. Clausen
2002-01-01
Bioremediation processes for recovery and reuse of CCA-treated wood invariably increase the cost of any secondary products manufactured from the remediated fiber. Microbial remediation using either bacteria or fungi has been shown to remove heavy metals from CCA-treated southern yellow pine (SYP). In a two-step remediation process utilizing oxalic acid extraction and...
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Microwave-assisted organic acids extraction of chromate copper arsenate (CCA)-treated southern pine
Bin Yu; Chung Y. Hse; Todd F. Shupe
2010-01-01
The extraction effects of acid concentration, reaction time and temperature in a microwave reactor on recovery of CCA-treated wood were evaluated. Extraction of copper, chromium, and arsenic metals from chromated copper arsenate (CCA)-treated southern pine wood samples with two different organic acids (i.e., acetic acid and oxalic acid) was investigated using a...
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An analysis of the physical properties of recovered CCA-treated wood from residential decks
David Bailey; Robert L. Smith; Philip A. Araman
2004-01-01
A large volume of CCA-treated wood removed from residential decks is disposed of in landfills every year, and better environmentally conscious alternatives are needed. Recycling CCA-treated wood from the decks could be a feasible alternative, but there is a lack of knowledge regarding the physical properties of the material. This research analyzed the chemical and...
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A distributed data base management capability for the deep space network
NASA Technical Reports Server (NTRS)
Bryan, A. I.
1976-01-01
The Configuration Control and Audit Assembly (CCA) is reported that has been designed to provide a distributed data base management capability for the DSN. The CCA utilizes capabilities provided by the DSN standard minicomputer and the DSN standard nonreal time high level management oriented programming language, MBASIC. The characteristics of the CCA for the first phase of implementation are described.
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Recycling of decommissioned CCA-treated wood into value-added enigineered wood products
Todd F. Shupe; Chung-Yun Hse
2003-01-01
Chromatcd copper arsenate (CCA) treated wood has been most widely used in North America since the 1970's for many exterior application such as decks, fences, playground equipment, utility poles, and others. A large volume of CCA-treated wood is currently coming out of service. Traditional disposal methods such as landfilling and incineration are not without...
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Physical and mechanical properties of flakeboard produced from recycled CCA-treated wood
W. Li; T.F. Shupe; Chung-Yun Hse
2004-01-01
Chromated copper arsenate (CCA) treated wood has been most widely used in North America since the 1970s for many exterior applications such as decks, fences, playground equipment, utility poles, and others. A large volume of CCA-treated wood is currently coming out of service. Traditional disposal methods such as landfilling and incineration are not without adverse...
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Increased PCDD/F formation in the bottom ash from fires of CCA-treated wood.
Tame, N W; Dlugogorski, B Z; Kennedy, E M
2003-03-01
Bottom ash that was the result of the combustion of chromated copper arsenate (CCA) treated wood under controlled fire conditions showed an increase of several orders of magnitude in the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), compared to that of untreated timber. Wood that has been pressure treated with CCA contains copper (II), which is known to catalyse the so-called de novo formation of PCDD/Fs. Comparable levels of PCDD/Fs would be expected in residual ash from burning CCA-treated wood in backyard fires, stoves and wood heaters, as a consequence of similar combustion conditions.
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Intrahepatic cholangiocarcinoma: current management and emerging therapies.
Rahnemai-Azar, Amir A; Weisbrod, Allison B; Dillhoff, Mary; Schmidt, Carl; Pawlik, Timothy M
2017-05-01
Intrahepatic cholangiocarcinoma (iCCA) is a malignancy with an increasing incidence and a high-case fatality. While surgery offers the best hope at long-term survival, only one-third of tumors are amenable to surgical resection at the time of the diagnosis. Unfortunately, conventional chemotherapy offers limited survival benefit in the management of unresectable or metastatic disease. Recent advances in understanding the molecular pathogenesis of iCCA and the use of next-generation sequencing techniques have provided a chance to identify 'target-able' molecular aberrations. These novel molecular therapies offer the promise to personalize therapy for patients with iCCA and, in turn, improve the outcomes of patients. Area covered: We herein review the current management options for iCCA with a focus on defining both established and emerging therapies. Expert commentary: Surgical resection remains as an only hope for cure in iCCA patients. However, frequently the diagnosis is delayed till advanced stages when surgery cannot be offered; signifying the urge for specific diagnostic tumor biomarkers and targeted therapies. New advances in genomic profiling have contributed to a better understanding of the landscape of molecular alterations in iCCA and offer hope for the development of novel diagnostic biomarkers and targeted therapies.
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The anticancer effects of Resina Draconis extract on cholangiocarcinoma.
Wen, Feng; Zhao, Xiangxuan; Zhao, Yun; Lu, Zaiming; Guo, Qiyong
2016-11-01
Cholangiocarcinoma (CCA) is a relatively rare, heterogeneous malignant tumor with poor clinical outcomes. Because of high insensitivity to chemotherapy and radiotherapy, there are no effective treatment options. Efforts to identify and develop new agents for prevention and treatment of this deadly disease are urgent. Here, we assessed the apoptotic cytotoxicity of Resina Draconis extract (RDE) using in vitro and in vivo assays and identified the mechanisms underlying antitumor effects of RDE. RDE was obtained via vacuum distillation of Resina Draconis with 75 % ethanol. The ethanol extract could inhibit CCA cell proliferation and trigger apoptotic cell death in both QBC939 and HCCC9810 cell lines in a time- and concentration-dependent manner. RDE treatment resulted in intracellular caspase-8 and poly (ADP-ribose) polymerase protease activation. RDE significantly downregulated antiapoptotic protein survivin expression and upregulated proapoptotic protein Bak expression. RDE also inhibited CCA tumor growth in vivo. We observed that human CCA tissues had much higher survivin expression than did paired adjacent normal tissue. Taken together, the current data suggested that RDE has anticancer effects on CCA, and that RDE could function as a novel anticancer agent to benefit patients with CCA.
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Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Chu, Cordia
2018-04-18
Climate change and climate-sensitive disasters significantly impact health. Linking Disaster Risk Reduction (DRR) and Climate Change Adaptation (CCA) is essential for addressing these ever present, complex and increasing risks. Recent calls have been made to build these links in health. However, there is a need to clearly articulate why linking DRR and CCA is important in health. Furthermore, little is known about how DRR and CCA should be linked in health. By extensively examining relevant literature, this review presents the current state of knowledge of linking DRR and CCA in health. This includes the potential for maximising conceptual synergies such as building resilience, and reducing vulnerability and risk. Additionally, technical and operational synergies are identified to link DRR and CCA in health, including: policy, Early Warning Systems, vulnerability and risk assessment, health systems strengthening, infrastructure resilience, disaster preparedness and response, and health impact pathways. Public health actors have a central role in building these links due to their expertise, work functions, and experience in addressing complex health risks. The review concludes with recommendations for future research, including how to better link DRR and CCA in health; and the opportunities, challenges and enablers to build and sustain these links.
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Zhang, Dawei; Li, Haiyan; Xie, Juping; Jiang, Decan; Cao, Liangqi; Yang, Xuewei; Xue, Ping; Jiang, Xiaofeng
2018-06-01
The aim of the present study was to elucidate whether, and how, long intergenic non-protein coding RNA 1296 (LINC01296) is involved in the modulation of human cholangiocarcinoma (CCA) development and progression. Microarray data analysis and reverse transcription-quantitative polymerase chain reaction analysis demonstrated that LINC01296 was significantly upregulated in human CCA compared with nontumor tissues. Furthermore, the expression of LINC01296 in human CCA was positively associated with tumor severity and clinical stage. Knockdown of LINC01296 dramatically suppressed the viability, migration and invasion of RBE and CCLP1 cells, and promoted cell apoptosis in vitro. Furthermore, LINC01296 knockdown inhibited tumor growth in a xenograft model. Mechanistically, LINC01296 was demonstrated to sponge microRNA-5095 (miR-5095), which targets MYCN proto-oncogene bHLH transcription factor (MYCN) mRNA in human CCA. By inhibition of miR-5095, LINC01296 overexpression upregulated the expression of MYCN and promoted cell viability, migration and invasion in CCA cells. The results reveal that the axis of LINC01296/miR-5095/MYCN may be a mechanism to regulate CCA development and progression.
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Deng, Hao; Lu, Qian; Xu, Hongbo; Deng, Xiong; Yuan, Lamei; Yang, Zhijian; Guo, Yi; Lin, Qiongfen; Xiao, Jingjing; Guan, Liping; Song, Zhi
2016-01-01
Congenital contractural arachnodactyly (CCA, OMIM 121050), also known as Beals-Hecht syndrome, is an autosomal dominant disorder of connective tissue. CCA is characterized by arachnodactyly, dolichostenomelia, pectus deformities, kyphoscoliosis, congenital contractures and a crumpled appearance of the helix of the ear. The aim of this study is to identify the genetic cause of a 4-generation Chinese family of Tujia ethnicity with congenital contractural arachnodactyly by exome sequencing. The clinical features of patients in this family are consistent with CCA. A novel missense mutation, c.3769T>C (p.C1257R), in the fibrillin 2 gene (FBN2) was identified responsible for the genetic cause of our family with CCA. The p.C1257R mutation occurs in the 19th calcium-binding epidermal growth factor-like (cbEGF) domain. The amino acid residue cysteine in this domain is conserved among different species. Our findings suggest that exome sequencing is a powerful tool to discover mutation(s) in CCA. Our results may also provide new insights into the cause and diagnosis of CCA, and may have implications for genetic counseling and clinical management. PMID:27196565
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Kaewpitoon, Soraya J; Rujirakul, Ratana; Loyd, Ryan A; Matrakool, Likit; Sangkudloa, Amnat; Kaewthani, Sarochinee; Khemplila, Kritsakorn; Eaksanti, Thawatchai; Phatisena, Tanida; Kujapun, Jirawoot; Norkaew, Jun; Joosiri, Apinya; Kaewpitoon, Natthawut
2016-01-01
Cholangiocarcinoma (CCA) is a serious health problem in Thailand, particularly in northeastern and northern regions, but epidemiological studies are scarce and the spatial distribution of CCA remains to be determined. A database for the population at risk is required for monitoring, surveillance and organization of home health care. This study aim was to geo-visually display the distribution of CCA in northeast Thailand, using a geographic information system and Google Earth. A cross-sectional survey was carried out in 9 sub-districts and 133 villages in Chum Phuang district, Nakhon Ratchasima province during June and October 2015. Data on demography, and the population at risk for CCA were combined with the points of villages, sub-district boundaries, district boundaries, and points of hospitals in districts, then fed into a geographical information system. After the conversion, all of the data were imported into Google Earth for geo-visualization. A total of 11,960 from 83,096 population were included in this study. Females and male were 52.5%, and 47.8%, the age group 41-50 years old 33.3%. Individual risk for CCA was identifed and classified by using the Korat CCA verbal screening test as low (92.8%), followed by high risk (6.74%), and no (0.49%), respectively. Gender (X2-test=1143.63, p-value= 0.001), age group (X2-test==211.36, p-value=0.0001), and sub-district (X2-test=1471.858, p-value=0.0001) were significantly associated with CCA risk. Spatial distribution of the population at risk for CCA in Chum Phuang district was viewed with Google Earth. Geo-visual display followed Layer 1: District, Layer 2: Sub-district, Layer 3: Number of low risk in village, Layer 4: Number of high risk in village, and Layer 5: Hospital in Chum Phuang District and their related catchment areas. We present the first risk geo-visual display of CCA in this rural community, which is important for spatial targeting of control efforts. Risk appears to be strongly associated with gender, age group, and sub-district. Therefor, spatial distribution is suitable for the use in the further monitoring, surveillance, and home health care for CCA.
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Zhang, Fu-Hui; Ren, Hong-Yue; Shen, Jin-Xing; Zhang, Xiao-Yun; Ye, Hui-Ming; Shen, Dong-Yan
2017-10-01
Magnolol has shown the potential anticancer properties against a variety of cancers. However, the role of magnolol in cholangiocarcinoma (CCA) cells is unknown. In this study, we assessed the effect of magnolol on the CCA cells. CCA cells were treated with magnolol in the absence or presence of TNFα, the activator for NF-κB. After co-incubation with magnolol, cell proliferation and growth were examined by MTT, colony formation and xenograft tumors; cell cycle was analyzed by flow cytometry; cell migration and invasion were detected by wound healing and transwell assays; the expression of PCNA, Ki67, CyclinD1, MMP-2, MMP-7 and MMP-9 and NF-κB pathway were evaluated by using Western blot. Magnolol inhibited the abilities of CCA cell growth, migration and invasion accompanying with a decreased expression of PCNA, Ki67, MMP-2, MMP-7 and MMP-9 (all P<0.05). with magnolol induced cell cycle arrest in G1 phase with a downregulation of cell cycle protein CyclinD1 (all P<0.05). In addition, magnolol suppressed the expression of p-IκBα and p-P65 and the effect of magnolol on CCA cells could be inhibited by TNFα. Magnolol could inhibit the growth, migration and invasion of CCA cells through regulation of NF-κB pathway, and these data indicate that magnolol is a potential candidate for treating of CCA. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Xu, Yi; Yao, Yue; Zhong, Xiangyu; Leng, Kaiming; Qin, Wei; Qu, Lijun; Cui, Yunfu; Jiang, Xingming
2018-02-05
Cholangiocarcinoma (CCA) is one of the most aggressive malignancies with increasing worldwide incidence and is characterized by unfavorable prognosis due to its early invasive characteristics and poor response to chemotherapy or radiotherapy. Accumulating evidence has indicated that aberrantly expressed circular RNAs (circRNAs) are involved in cancer development and progression. However, their clinical values and biological roles in CCA remain unclear. Hsa_circ_0001649, a novel cancer-related circRNA, has been previously reported to be downregulated in hepatocellular carcinoma and gastric cancer. In the present study, qRT-PCR was carried out to measure the expression of hsa_circ_0001649 in CCA tissue samples and cell lines, and the correlation between hsa_circ_0001649 expression and clinicopathologic features was analyzed. The biological functions of hsa_circ_0001649 in CCA cells were evaluated both in vitro and in vivo. As a result, hsa_circ_0001649 was aberrantly downregulated in CCA tissues and cells, and this downregulation was associated with tumor size and differentiation grade in CCA. In addition, hsa_circ_0001649 overexpression caused tumor suppressive effects via inhibiting cell proliferation, migration and invasion; inducing cell apoptosis in KMBC and Huh-28 cells. On the contrary, silencing of hsa_circ_0001649 caused the opposite phenotypes. Furthermore, tumor xenograft study confirmed the in vitro results. Collectively, our findings suggest that hsa_circ_0001649 might be a rational CCA-related therapeutic target. Copyright © 2018 Elsevier Inc. All rights reserved.
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Froment, Marie-Anne; Gomez, Scarlett L; Roux, Audrey; DeRouen, Mindy C; Kidd, Elizabeth A
2014-06-01
This study aimed to evaluate the incidence of cervical cancer by nativity [United States (US) versus non-US], neighborhood socioeconomic status and ethnic enclave among Hispanics and Asians in California. Using data from the California Cancer Registry, information on all primary invasive cervical cancer (Cca) patients diagnosed in California from January 1, 1990 through December 31, 2004 was obtained. We analyzed the influence of enclave, socioeconomic status and nativity on Cca incidence. Among the 22,189 Cca cases diagnosed between 1990 and 2004, 50% were non-Hispanic white, 39% Hispanic and 11% Asian women, and 63% US-born. Seventy percent of the Cca cases were squamous cell carcinoma, 19% adenocarcinoma and 11% other histologies. Higher incidence of Cca was observed in high enclave (76%) and low socioeconomic status (70%) neighborhoods. By ethnic group, US-born women showed lower rates of squamous cell carcinoma compared to foreign-born women. Hispanics living in low socioeconomic and high enclave had 12.7 times higher rate of Cca than those living in high socioeconomic, low enclave neighborhoods. For Asian women incidence rates were 6 times higher in the low socioeconomic, high enclave neighborhoods compared to those living in high socioeconomic, low enclave neighborhoods. More targeted outreach to increase Pap smear screening and human papilloma virus vaccination for women living in high enclave neighborhoods can help decrease the incidence of Cca in these groups of women. Copyright © 2014 Elsevier Inc. All rights reserved.
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Liquefaction of CCA-treated wood and elimination of metals from the solvent by precipitation
Lianzhen Lin; Chung-Yun Hse
2005-01-01
Spent chromated copper arsenate (CCA)-treated wood was liquefied in polyethylene glycol 400/glycerin (2:1 w/w). Sulfuric acid (95-98%) and ferrous salts (FeSO4â¢7H2O or FeCl2â¢4H2O) were used as catalysts and additives, respectively. The resulting liquefied CCA-treated wood was...
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Carol A. Clausen
2004-01-01
Remediation processes for recovery and reuse of chromated-copper-arsenate-(CCA) treated wood are not gaining wide acceptance because they are more expensive than landfill disposal. One reason is the high cost of the nutrient medium used to culture the metal tolerant bacterium, Bacillus licheniformis, which removes 70-100% of the copper, chromium, and arsenic from CCA-...
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Soneson, Charlotte; Lilljebjörn, Henrik; Fioretos, Thoas; Fontes, Magnus
2010-04-15
With the rapid development of new genetic measurement methods, several types of genetic alterations can be quantified in a high-throughput manner. While the initial focus has been on investigating each data set separately, there is an increasing interest in studying the correlation structure between two or more data sets. Multivariate methods based on Canonical Correlation Analysis (CCA) have been proposed for integrating paired genetic data sets. The high dimensionality of microarray data imposes computational difficulties, which have been addressed for instance by studying the covariance structure of the data, or by reducing the number of variables prior to applying the CCA. In this work, we propose a new method for analyzing high-dimensional paired genetic data sets, which mainly emphasizes the correlation structure and still permits efficient application to very large data sets. The method is implemented by translating a regularized CCA to its dual form, where the computational complexity depends mainly on the number of samples instead of the number of variables. The optimal regularization parameters are chosen by cross-validation. We apply the regularized dual CCA, as well as a classical CCA preceded by a dimension-reducing Principal Components Analysis (PCA), to a paired data set of gene expression changes and copy number alterations in leukemia. Using the correlation-maximizing methods, regularized dual CCA and PCA+CCA, we show that without pre-selection of known disease-relevant genes, and without using information about clinical class membership, an exploratory analysis singles out two patient groups, corresponding to well-known leukemia subtypes. Furthermore, the variables showing the highest relevance to the extracted features agree with previous biological knowledge concerning copy number alterations and gene expression changes in these subtypes. Finally, the correlation-maximizing methods are shown to yield results which are more biologically interpretable than those resulting from a covariance-maximizing method, and provide different insight compared to when each variable set is studied separately using PCA. We conclude that regularized dual CCA as well as PCA+CCA are useful methods for exploratory analysis of paired genetic data sets, and can be efficiently implemented also when the number of variables is very large.
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Fabrication of all-inorganic nanocrystal solids through matrix encapsulation of nanocrystal arrays.
Kinder, Erich; Moroz, Pavel; Diederich, Geoffrey; Johnson, Alexa; Kirsanova, Maria; Nemchinov, Alexander; O'Connor, Timothy; Roth, Dan; Zamkov, Mikhail
2011-12-21
A general strategy for low-temperature processing of colloidal nanocrystals into all-inorganic films is reported. The present methodology goes beyond the traditional ligand-interlinking scheme and relies on encapsulation of morphologically defined nanocrystal arrays into a matrix of a wide-band gap semiconductor, which preserves optoelectronic properties of individual nanoparticles while rendering the nanocrystal film photoconductive. Fabricated solids exhibit excellent thermal stability, which is attributed to the heteroepitaxial structure of nanocrystal-matrix interfaces, and show compelling light-harvesting performance in prototype solar cells. © 2011 American Chemical Society
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Imaging and Screening of Cancer of the Gallbladder and Bile Ducts.
Sandrasegaran, Kumar; Menias, Christine O
2017-11-01
Biliary cancers include gallbladder cancer (GBC) and cholangiocarcinoma (CCA). GBC may appear as a mass replacing the gallbladder, thickened gallbladder wall, or polypoid lesion in the gallbladder. Gallbladder polyps with low risk of GBC (eg, 6- to 10-mm polyps without other risk factors) are screened with sonography. In general, polyps smaller than 5 mm are ignored and those larger than 10 mm require surgical consideration. Screening for CCA is less well-established. On imaging, CCA may be divided into mass-forming, periductal infiltrating, and intraductal types. This review discusses the current state of screening and diagnosis of GBC and CCA. Copyright © 2017 Elsevier Inc. All rights reserved.
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Joint Blind Source Separation by Multi-set Canonical Correlation Analysis
Li, Yi-Ou; Adalı, Tülay; Wang, Wei; Calhoun, Vince D
2009-01-01
In this work, we introduce a simple and effective scheme to achieve joint blind source separation (BSS) of multiple datasets using multi-set canonical correlation analysis (M-CCA) [1]. We first propose a generative model of joint BSS based on the correlation of latent sources within and between datasets. We specify source separability conditions, and show that, when the conditions are satisfied, the group of corresponding sources from each dataset can be jointly extracted by M-CCA through maximization of correlation among the extracted sources. We compare source separation performance of the M-CCA scheme with other joint BSS methods and demonstrate the superior performance of the M-CCA scheme in achieving joint BSS for a large number of datasets, group of corresponding sources with heterogeneous correlation values, and complex-valued sources with circular and non-circular distributions. We apply M-CCA to analysis of functional magnetic resonance imaging (fMRI) data from multiple subjects and show its utility in estimating meaningful brain activations from a visuomotor task. PMID:20221319
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Paik, Taejong; Hong, Sung-Hoon; Gaulding, E Ashley; Caglayan, Humeyra; Gordon, Thomas R; Engheta, Nader; Kagan, Cherie R; Murray, Christopher B
2014-01-28
We demonstrate thermally switchable VO2 metamaterials fabricated using solution-processable colloidal nanocrystals (NCs). Vanadium oxide (VOx) NCs are synthesized through a nonhydrolytic reaction and deposited from stable colloidal dispersions to form NC thin films. Rapid thermal annealing transforms the VOx NC thin films into monoclinic, nanocrystalline VO2 thin films that show a sharp, reversible metal-insulator phase transition. Introduction of precise concentrations of tungsten dopings into the colloidal VOx NCs enables the still sharp phase transition of the VO2 thin films to be tuned to lower temperatures as the doping level increases. We fabricate "smart", differentially doped, multilayered VO2 films to program the phase and therefore the metal-insulator behavior of constituent vertically structured layers with temperature. With increasing temperature, we tailored the optical response of multilayered films in the near-IR and IR regions from that of a strong light absorber, in a metal-insulator structure, to that of a Drude-like reflector, characteristic of a pure metallic structure. We demonstrate that nanocrystal-based nanoimprinting can be employed to pattern multilayered subwavelength nanostructures, such as three-dimensional VO2 nanopillar arrays, that exhibit plasmonic dipolar responses tunable with a temperature change.
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Identification of fucosylated Fetuin-A as a potential biomarker for cholangiocarcinoma.
Betesh, Lucy; Comunale, Mary Ann; Wang, Mengjun; Liang, Hongyan; Hafner, Julie; Karabudak, Aykan; Giama, Nasra H; Moser, Catherine D; Miyoshi, Eiji; Roberts, Lewis R; Block, Timothy M; Mehta, Anand
2017-09-01
Cholangiocarcinoma (CCA) is a malignancy of the bile ducts. The purpose of this discovery study was to identify effective serum markers for surveillance of cholangiocarcinoma. Using a glycomic method, patients with CCA were determined to have increased levels of alpha-1,3 and alpha-1,6 linked fucosylated glycan. Proteomic analysis of the serum fucosylated proteome identified proteins such as alpha-2-macroglobulin, kininogen, hemopexin, fetuin-A, alpha-1 anti-trypsin, and ceruloplasmin as being hyperfucosylated in HCC. The levels of these glycoproteins in 109 patients with CCA, primary sclerosing cholangitis (PSC), and control patients were compared to the performance of CA-19-9, the current "gold standard" assay for cholangiocarcinoma. Fucosylated Fetuin-A (fc-Fetuin-A) had the best ability to differentiate CCA from PSC, with an AUROC of 0.812 or 0.8665 at differentiating CCA from those with PSC or other liver disease. CA-19-9 had poor ability to differentiate PSC from cholangiocarcinoma (AUROC of 0.625). Using glycomic and proteomic methods we identified a set of proteins that contain altered glycan in the sera of those with CCA. One of these proteins, fucosylated Fetuin-A may have value in the surveillance of people at risk for the development of cholangiocarcinoma. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Suppression of pulmonary vasculature in lung perfusion MRI using correlation analysis.
Risse, Frank; Kuder, Tristan A; Kauczor, Hans-Ulrich; Semmler, Wolfhard; Fink, Christian
2009-11-01
The purpose of the study was to evaluate the feasibility of suppressing the pulmonary vasculature in lung perfusion MRI using cross-correlation analysis (CCA). Perfusion magnetic resonance imaging (MRI) (3D FLASH, TR/TE/flip angle: 0.8 ms/2.1 ms/40 degrees ) of the lungs was performed in seven healthy volunteers at 1.5 Tesla after injection of Gd-DTPA. CCA was performed pixel-wise in lung segmentations using the signal time-course of the main pulmonary artery and left atrium as references. Pixels with high correlation coefficients were considered as arterial or venous and excluded from further analysis. Quantitative perfusion parameters [pulmonary blood flow (PBF) and volume (PBV)] were calculated for manual lung segmentations separately, with the entire left and right lung with all intrapulmonary vessels (IPV) included, excluded manually or excluded using CCA. The application of CCA allowed reliable suppression of hilar and large IPVs. Using vascular suppression by CCA, perfusion parameters were significantly reduced (p
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NASA Technical Reports Server (NTRS)
Liu, Z.; Xia, M.; Poovaiah, B. W.
1998-01-01
cDNA clones of chimeric Ca2+/calmodulin-dependent protein kinase (CCaMK) from tobacco (TCCaMK-1 and TCCaMK-2) were isolated and characterized. The polypeptides encoded by TCCaMK-1 and TCCaMK-2 have 15 different amino acid substitutions, yet they both contain a total of 517 amino acids. Northern analysis revealed that CCaMK is expressed in a stage-specific manner during anther development. Messenger RNA was detected when tobacco bud sizes were between 0.5 cm and 1.0 cm. The appearance of mRNA coincided with meiosis and became undetectable at later stages of anther development. The reverse polymerase chain reaction (RT-PCR) amplification assay using isoform-specific primers showed that both of the CCaMK mRNAs were expressed in anther with similar expression patterns. The CCaMK protein expressed in Escherichia coli showed Ca2+-dependent autophosphorylation and Ca2+/calmodulin-dependent substrate phosphorylation. Calmodulin isoforms (PCM1 and PCM6) had differential effects on the regulation of autophosphorylation and substrate phosphorylation of tobacco CCaMK, but not lily CCaMK. The evolutionary tree of plant serine/threonine protein kinases revealed that calmodulin-dependent kinases form one subgroup that is distinctly different from Ca2+-dependent protein kinases (CDPKs) and other serine/threonine kinases in plants.
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Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Chu, Cordia
2018-01-01
Climate change and climate-sensitive disasters significantly impact health. Linking Disaster Risk Reduction (DRR) and Climate Change Adaptation (CCA) is essential for addressing these ever present, complex and increasing risks. Recent calls have been made to build these links in health. However, there is a need to clearly articulate why linking DRR and CCA is important in health. Furthermore, little is known about how DRR and CCA should be linked in health. By extensively examining relevant literature, this review presents the current state of knowledge of linking DRR and CCA in health. This includes the potential for maximising conceptual synergies such as building resilience, and reducing vulnerability and risk. Additionally, technical and operational synergies are identified to link DRR and CCA in health, including: policy, Early Warning Systems, vulnerability and risk assessment, health systems strengthening, infrastructure resilience, disaster preparedness and response, and health impact pathways. Public health actors have a central role in building these links due to their expertise, work functions, and experience in addressing complex health risks. The review concludes with recommendations for future research, including how to better link DRR and CCA in health; and the opportunities, challenges and enablers to build and sustain these links. PMID:29670057
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Segmentized Clear Channel Assessment for IEEE 802.15.4 Networks.
Son, Kyou Jung; Hong, Sung Hyeuck; Moon, Seong-Pil; Chang, Tae Gyu; Cho, Hanjin
2016-06-03
This paper proposed segmentized clear channel assessment (CCA) which increases the performance of IEEE 802.15.4 networks by improving carrier sense multiple access with collision avoidance (CSMA/CA). Improving CSMA/CA is important because the low-power consumption feature and throughput performance of IEEE 802.15.4 are greatly affected by CSMA/CA behavior. To improve the performance of CSMA/CA, this paper focused on increasing the chance to transmit a packet by assessing precise channel status. The previous method used in CCA, which is employed by CSMA/CA, assesses the channel by measuring the energy level of the channel. However, this method shows limited channel assessing behavior, which comes from simple threshold dependent channel busy evaluation. The proposed method solves this limited channel decision problem by dividing CCA into two groups. Two groups of CCA compare their energy levels to get precise channel status. To evaluate the performance of the segmentized CCA method, a Markov chain model has been developed. The validation of analytic results is confirmed by comparing them with simulation results. Additionally, simulation results show the proposed method is improving a maximum 8.76% of throughput and decreasing a maximum 3.9% of the average number of CCAs per packet transmission than the IEEE 802.15.4 CCA method.
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Segmentized Clear Channel Assessment for IEEE 802.15.4 Networks
Son, Kyou Jung; Hong, Sung Hyeuck; Moon, Seong-Pil; Chang, Tae Gyu; Cho, Hanjin
2016-01-01
This paper proposed segmentized clear channel assessment (CCA) which increases the performance of IEEE 802.15.4 networks by improving carrier sense multiple access with collision avoidance (CSMA/CA). Improving CSMA/CA is important because the low-power consumption feature and throughput performance of IEEE 802.15.4 are greatly affected by CSMA/CA behavior. To improve the performance of CSMA/CA, this paper focused on increasing the chance to transmit a packet by assessing precise channel status. The previous method used in CCA, which is employed by CSMA/CA, assesses the channel by measuring the energy level of the channel. However, this method shows limited channel assessing behavior, which comes from simple threshold dependent channel busy evaluation. The proposed method solves this limited channel decision problem by dividing CCA into two groups. Two groups of CCA compare their energy levels to get precise channel status. To evaluate the performance of the segmentized CCA method, a Markov chain model has been developed. The validation of analytic results is confirmed by comparing them with simulation results. Additionally, simulation results show the proposed method is improving a maximum 8.76% of throughput and decreasing a maximum 3.9% of the average number of CCAs per packet transmission than the IEEE 802.15.4 CCA method. PMID:27271626
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NASA Astrophysics Data System (ADS)
Wang, Tehua; Chong, Siying; Wang, Tongtong; Lu, Huiyi; Ji, Min
2018-01-01
In order to correlate the physicochemical properties of carbon-covered alumina (CCA) materials with their catalytic performance for oxidative dehydrogenation of ethylbenzene with CO2 (CO2-ODEB), a series of CCA materials with diverse carbon contents (8.7-31.3 wt%) and pyrolysis temperatures (600-800 °C), which were synthesized via an impregnation method followed by pyrolysis, were applied. These catalytic materials were characterized by TGA, N2 physisorption, XRD, Raman spectroscopy and XPS techniques. It was found that the catalytic performance of these CCA materials highly depended on their physicochemical properties, and the optimum CCA catalyst exhibited much better catalytic stability than conventional hydroxyl carbon nanotubes. Below an optimum value of carbon content, the CCA catalyst preserved the main pore characteristics of the Al2O3 support and its catalytic activity increased with the carbon content. Excessive carbon loading resulted in significant textural alterations and thereby decreased both the ethylbenzene conversion and styrene selectivity. On the other hand, high pyrolysis temperature was detrimental to the ordered graphitic structure of the carbon species within the Al2O3 pore. The decreased ordered graphitic degree was found to be associated with the loss of the surface active carbonyl groups, consequently hampering the catalytic efficiency of the CCA catalyst.
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Mechanistic principles of colloidal crystal growth by evaporation-induced convective steering.
Brewer, Damien D; Allen, Joshua; Miller, Michael R; de Santos, Juan M; Kumar, Satish; Norris, David J; Tsapatsis, Michael; Scriven, L E
2008-12-02
We simulate evaporation-driven self-assembly of colloidal crystals using an equivalent network model. Relationships between a regular hexagonally close-packed array of hard, monodisperse spheres, the associated pore space, and selectivity mechanisms for face-centered cubic microstructure propagation are described. By accounting for contact line rearrangement and evaporation at a series of exposed menisci, the equivalent network model describes creeping flow of solvent into and through a rigid colloidal crystal. Observations concerning colloidal crystal growth are interpreted in terms of the convective steering hypothesis, which posits that solvent flow into and through the pore space of the crystal may play a major role in colloidal self-assembly. Aspects of the convective steering and deposition of high-Peclet-number rigid spherical particles at a crystal boundary are inferred from spatially resolved solvent flow into the crystal. Gradients in local flow through boundary channels were predicted due to the channels' spatial distribution relative to a pinned free surface contact line. On the basis of a uniform solvent and particle flux as the criterion for stability of a particular growth plane, these network simulations suggest the stability of a declining {311} crystal interface, a symmetry plane which exclusively propagates fcc microstructure. Network simulations of alternate crystal planes suggest preferential growth front evolution to the declining {311} interface, in consistent agreement with the proposed stability mechanism for preferential fcc microstructure propagation in convective assembly.
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Low Impact of Traditional Risk Factors on Carotid Intima-Media Thickness: The ELSA-Brasil Cohort.
Santos, Itamar S; Alencar, Airlane P; Rundek, Tatjana; Goulart, Alessandra C; Barreto, Sandhi M; Pereira, Alexandre C; Benseñor, Isabela M; Lotufo, Paulo A
2015-09-01
There is little information about how much traditional cardiovascular risk factors explain common carotid artery intima-media thickness (CCA-IMT) variance. We aimed to study to which extent CCA-IMT values are determined by traditional risk factors and which commonly used measurements of blood pressure, glucose metabolism, lipid profile, and adiposity contribute the most to this determination in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) cohort baseline. We analyzed 9792 individuals with complete data and CCA-IMT measurements. We built multiple linear regression models using mean left and right CCA-IMT as the dependent variable. All models were stratified by sex. We also analyzed individuals stratified by 10-year coronary heart disease risk and, in separate, those with no traditional risk factors. Main models' R(2) varied between 0.141 and 0.373. The major part of the explained variance in CCA-IMT was because of age and race. Indicators of blood pressure, lipid profile, and adiposity that most frequently composed the best models were pulse pressure, low-density lipoprotein/high-density lipoprotein ratio, and neck circumference. The association between neck circumference and CCA-IMT persisted significant even after further adjustment for vessel sizes and body mass index. Indicators of glucose metabolism had smaller contribution. We found that >60% of CCA-IMT were not explained by demographic and traditional cardiovascular risk factors, which highlights the need to study novel risk factors. Pulse pressure, low-density lipoprotein/high-density lipoprotein ratio, and neck circumference were the most consistent contributors. © 2015 American Heart Association, Inc.
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NASA Technical Reports Server (NTRS)
Patil, Shameekumar; Takezawa, D.; Poovaiah, B. W.
1995-01-01
Calcium, a universal second messenger, regulates diverse cellular processes in eukaryotes. Ca-2(+) and Ca-2(+)/calmodulin-regulated protein phosphorylation play a pivotal role in amplifying and diversifying the action of Ca-2(+)- mediated signals. A chimeric Ca-2(+)/calmodulin-dependent protein kinase (CCaMK) gene with a visinin-like Ca-2(+)- binding domain was cloned and characterized from lily. The cDNA clone contains an open reading frame coding for a protein of 520 amino acids. The predicted structure of CCaMK contains a catalytic domain followed by two regulatory domains, a calmodulin-binding domain and a visinin-like Ca-2(+)-binding domain. The amino-terminal region of CCaMK contains all 11 conserved subdomains characteristic of serine/threonine protein kinases. The calmodulin-binding region of CCaMK has high homology (79%) to alpha subunit of mammalian Ca-2(+)/calmodulin-dependent protein kinase. The calmodulin-binding region is fused to a neural visinin-like domain that contains three Ca-2(+)-binding EF-hand motifs and a biotin-binding site. The Escherichia coli-expressed protein (approx. 56 kDa) binds calmodulin in a Ca-2(+)-dependent manner. Furthermore, Ca-45-binding assays revealed that CCaMK directly binds Ca-2(+). The CCaMK gene is preferentially expressed in developing anthers. Southern blot analysis revealed that CCaMK is encoded by a single gene. The structural features of the gene suggest that it has multiple regulatory controls and could play a unique role in Ca-2(+) signaling in plants.
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Triglycerides and carotid intima-media thickness in ischemic stroke patients.
Batluk, Jana; Leonards, Christopher O; Grittner, Ulrike; Lange, Kristin Sophie; Schreiber, Stephan J; Endres, Matthias; Ebinger, Martin
2015-11-01
Common carotid artery intima-media thickness (CCA-IMT) is an established marker for atherosclerosis. The role of triglycerides in CCA-IMT remains controversial. We sought to determine if elevated fasting and post-challenge triglycerides are associated with CCA-IMT. All acute ischemic stroke patients who participated in the Berlin "Cream & Sugar" study in the Charité Virchow and Charité Mitte Campuses between January 2009 and January 2014 and underwent carotid artery ultrasound studies were eligible for inclusion. A combined oral glucose and triglyceride tolerance test was performed 3-7 days after first ever ischemic stroke. Patients were classified according to triglyceride metabolism-namely, (1) patients reaching a maximum triglyceride levels 3 h post-challenge ("fast metabolizers," n = 37), (2) patients with increasing triglycerides 4 (medium metabolizers, n = 64), and (3) 5 h post-challenge ("slow metabolizers," n = 44; 13 missing). We included 158 patients (34% female; mean age 63 years, SD 14). Absolute non-fasting triglyceride levels were positively associated with CCA-IMT. A final multiple regression model revealed that older age, more severe strokes, and higher levels of fasting triglycerides were significantly and independently associated with higher mean CCA-IMT. Older age, higher waist-to-hip ratio, and higher levels of thyroid-stimulating hormone were independently associated with higher maximum CCA-IMT. Fasting triglycerides but not post-challenge triglycerides associate with CCA-IMT. An oral fat challenge may not add information on atherosclerotic status in ischemic stroke patients. The Berlin "Cream & Sugar" study is registered with EudraCT (2009-010356-97) and clinicaltrials.gov (NCT 01378468). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
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Understanding the CCA Standard Through Decaf
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumfert, G
2003-04-17
This document is a tutorial on the CCA Standard as realized through the Decaf implementation. Decaf does not equal the CCA standard much in the same way that Microsoft Visual C++ is not ANSI/ISO C++. This document was created because the CCA standard is evolving and still too fluid to nail down in a tutorial document. Because of its fluidity, and that it represents a hotbed of research and development, beginners can only start learning CCA by choosing one of the frameworks (warts and all). Decaf has just enough functionality to be a useful tool for beginners in the CCAmore » to get started on. Though it lacks many features of the bigger CCA frameworks (CCAFE [3], XCAT [10], and SciRUN [8]) where the heavy-duty research is still going on, it is the first CCA framework that is underpinned by Babel, which provides its language interoperability features. This document can also serve the dual-purpose of providing a reasonable-sized example of building an application using Babel. The entire source for Decaf is included in the examples/subdirectory of the Babel code distribution. This manual assumes the reader is a programmer who has a conceptual understanding of the Babel Language Interoperability Tool. They should be proficient in two or more of the following languages: Fortran77, C, C++, Java, or Python. Furthermore, this manual assumes the reader is familiar with the SPMD{sup 2} programming model that pervades the scientific computing community. Knowledge of and experience with MPI programming is helpful, but not strictly required.« less
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Al Ansari, Najwa; Kim, Bong Soo; Srirattanapong, Saowanee; Semelka, Charles T A; Ramalho, Miguel; Altun, Ersan; Woosley, John T; Calvo, Benjamin; Semelka, Richard C
2014-12-01
To determine MR features suggestive of mass-forming cholangiocarcinoma (CCA) or liver metastases of adenocarcinoma of unknown primary (AUP), and to compare the ability of two experienced radiologists to establish the correct diagnosis. 61 patients with CCA or AUP, with MRIs were placed into two groups: population 1, 28 patients with certain diagnosis of either CCA or AUP; and population 2, 33 patients with uncertain diagnosis. Using population 1 with known diagnosis, two investigators formulated imaging criteria for CCA or AUP, which represented phase 1 of the study. In phase 2, two independent radiologists categorized the patients in populations 1 and 2 as CCA or AUP using the formulated criteria. This categorization was compared with the patient medical records and pathologist review. Findings were tested for statistical significance. In phase 1, solitary lesion, multifocal lesions with dominant lesion, capsule retraction, and porta hepatis lymphadenopathy were features of CCA; multifocal lesions with similar size, and ring enhancement were features of AUP. The number of lesions, capsule retraction, and early tumor enhancement pattern were observed to be significant features (P < 0.05). In phase 2, agreement between the two radiologists was good (k = 0.663). For population 1, the agreement was good (k = 0.659), and was fair for population 2 (k = 0.293). Concordance between the two radiologists, medical record, and the pathologist was found in 41/61 (67%) patients. Distinctive features of CCA and AUP are identifiable on MRI images, which may aid the radiologist to establish the correct diagnosis.
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Sritana, Narongrit; Suriyo, Tawit; Kanitwithayanun, Jantamas; Songvasin, Benjaporn Homkajorn; Thiantanawat, Apinya; Satayavivad, Jutamaad
2018-06-08
Previous studies showed that glyphosate stimulates breast cancer cell growth via estrogen receptors. The present study investigated the effect of glyphosate on the estrogen signaling pathway involved in the induction of cholangiocarcinoma (CCA) cell growth. HuCCA-1, RMCCA-1 and MMNK-1 were chosen for comparison. The effects of glyphosate on cell growth, cell cycle and molecular signaling pathways were measured. The results showed that HuCCA-1 cells expressed estrogen receptor alpha (ERα), while ERα was not detected in RMCCA-1 and MMNK-1 cells. ERα was mostly expressed in cytoplasmic compartment of HuCCA-1 cells. Estradiol (E2) (10 -11 -10 -5 M) induced cell proliferation in HuCCA-1 but not in RMCCA-1 and MMNK-1 cells. Glyphosate at the same concentration range also induced HuCCA-1 cell proliferation. The S phase of the cell cycle, and protein levels of the cyclin family were significantly increased after treatment of glyphosate or E2. Both compounds also induced the expression of proliferative signaling-related proteins including ERα, VEGFR2, pERK, PI3K(p85), and PCNA. These effects of glyphosate and E2 were abolished by the ER antagonist, 4-hydroxytamoxifen and U0126, a MEK inhibitor. The data from this study indicate that glyphosate can induce cell growth in ERα positive CCA cells through non-genomic estrogen receptor/ERK1/2 signaling pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Potential arsenic exposures in 25 species of zoo animals living in CCA-wood enclosures.
Gress, J; da Silva, E B; de Oliveira, L M; Zhao, Di; Anderson, G; Heard, D; Stuchal, L D; Ma, L Q
2016-05-01
Animal enclosures are often constructed from wood treated with the pesticide chromated copper arsenate (CCA), which leaches arsenic (As) into adjacent soil during normal weathering. This study evaluated potential pathways of As exposure in 25 species of zoo animals living in CCA-wood enclosures. We analyzed As speciation in complete animal foods, dislodgeable As from CCA-wood, and As levels in enclosure soils, as well as As levels in biomarkers of 9 species of crocodilians (eggs), 4 species of birds (feathers), 1 primate species (hair), and 1 porcupine species (quills). Elevated soil As in samples from 17 enclosures was observed at 1.0-110mg/kg, and enclosures housing threatened and endangered species had As levels higher than USEPA's risk-based Eco-SSL for birds and mammals of 43 and 46mg/kg. Wipe samples of CCA-wood on which primates sit had dislodgeable As residues of 4.6-111μg/100cm(2), typical of unsealed CCA-wood. Inorganic As doses from animal foods were estimated at 0.22-7.8μg/kg bw/d. Some As levels in bird feathers and crocodilian eggs were higher than prior studies on wild species. However, hair from marmosets had 6.37mg/kg As, 30-fold greater than the reference value, possibly due to their inability to methylate inorganic As. Our data suggested that elevated As in soils and dislodgeable As from CCA-wood could be important sources of As exposure for zoo animals. Published by Elsevier B.V.
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Hahnvajanawong, Chariya; Chaiyagool, Jariya; Seubwai, Wunchana; Bhudhisawasdi, Vajarabhongsa; Namwat, Nisana; Khuntikeo, Narong; Sripa, Banchob; Pugkhem, Ake; Tassaneeyakul, Wichittra
2012-01-01
AIM: To determine whether expression of certain enzymes related to 5-fluorouracil (5-FU) metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma (CCA). METHODS: The histoculture drug response assay (HDRA) was performed using surgically resected CCA tissues. Tumor cell viability was determined morphologically with hematoxylin and eosin- and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues. The mRNA expression of thymidine phosphorylase (TP), orotate phosphoribosyl transferase (OPRT), thymidylate synthase (TS), and dihydropyrimidine dehydrogenase (DPD) was determined with real-time reverse transcriptase-polymerase chain reaction. The levels of gene expression and the sensitivity to 5-FU were evaluated. RESULTS: Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital, Khon Kaen University from 2007 to 2009. HDRA was used to determine the response of these CCA tissues to 5-FU. Based on the dose-response curve, 200 μg/mL 5-FU was selected as the test concentration. The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU. When the relationship between TP, OPRT, TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined, only OPRT mRNA expression was significantly correlated with the response to 5-FU. The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group (0.41 ± 0.25 vs 0.22 ± 0.12, P < 0.05). CONCLUSION: OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA. Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients. PMID:22912546
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Ahlering, M A; Maldonado, J E; Eggert, L S; Fleischer, R C; Western, D; Brown, J L
2013-06-01
Biodiversity conservation strategies are increasingly focused on regions outside national protected areas, where animals face numerous anthropogenic threats and must coexist with human settlements, livestock, and agriculture. The effects of these potential threats are not always clear, but they could have profound implications for population viability. We used savannah elephants (Loxodonta africana) as a case study to assess the physiological stress associated with living in a human-livestock-dominated landscape. We collected samples over two 3-month periods in 2007 and 2008. We used fecal DNA to identify 96 individual elephants in a community conservation area (CCA) and measured fecal glucocorticoid metabolite (FGM) concentrations as a proxy for stress. The CCA is community Maasai land managed for livestock and wildlife. We compared the FGM concentrations from the CCA to FGM concentrations of 40 elephants in Amboseli National Park and 32 elephants in the Maasai Mara National Reserve, where human settlements and intense livestock grazing were absent. In the CCA, we found no significant individual differences in FGM concentrations among the elephants in 2007 (p = 0.312) or 2008 (p = 0.412) and no difference between years (p = 0.616). The elephants in the CCA had similar FGM concentrations to the Maasai Mara population, but Amboseli elephants had significantly lower FGM concentrations than those in either Maasai Mara or the CCA (Tukey pairwise test, p < 0.001), due primarily to females excreting significantly lower FGM relative to males (p = 0.025). In the CCA, there was no relation among female group size, average pairwise group relatedness, and average group FGM concentration. We found no clear evidence of chronic stress in elephants living on CCA communal land, which is encouraging for conservation strategies promoting the protection of animals living outside protected areas. Conservation Biology © 2013 Society for Conservation Biology No claim to original US government works.
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Kaewpitoon, Soraya J; Rujirakul, Ratana; Sangkudloa, Amnat; Kaewthani, Sarochinee; Khemplila, Kritsakorn; Cherdjirapong, Karuna; Kujapun, Jirawoot; Norkaew, Jun; Chavengkun, Wasugree; Ponphimai, Sukanya; Polsripradist, Poowadol; Padchasuwan, Natnapa; Joosiri, Apinya; Wakkhuwattapong, Parichart; Loyd, Ryan A; Matrakool, Likit; Tongtawee, Taweesak; Panpimanmas, Sukij; Kaewpitoon, Natthawut
2016-01-01
Cholangiocarcinoma (CCA), a major problem of health in Thailand, particularly in Northeastern and Northern regions, is generally incurable and rapidly lethal because of presentation in stage 3 or 4. Early diagnosis of stage 1 and 2 could allow better survival. Therefore, this study aimed to provide a distribution map of populations at risk for CCA in BuaYai district of Nakhon Ratchasima province, Northeast Thailand. A cross-sectional survey was carried out in 10 sub-districts and 122 villages, during June and November 2015. The populations at risk for CCA were screened using the Korat CCA verbal screening test (KCVST) and then risk areas were displayed by using Google map (GM). A total of 11,435 individuals from a 26,198 population completed the KCVST. The majority had a low score of risk for CCA (1-4 points; 93.3%). High scores with 6, 7 and 8 points accounted for 1.20%, 0.13% and 0.02%. The population at risk was found frequently in sub-district municipalities, followed by sub-district administrative organization and town municipalities, (F=396.220, P-value=0.000). Distribution mapping comprised 11 layers: 1, district; 2, local administrative organization; 3, hospital; 4, KCVST opisthorchiasis; 5, KCVST praziquantel used; 6, KCVST cholelithiasis; 7, KCVST raw fish consumption; 8, KCVST alcohol consumption; 9, KCVST pesticide used; 10, KCVST relative family with CCA; and 11, KCVST naive northeastern people. Geovisual display is now available online. This study indicated that the population at high risk of CCA in Bua Yai district is low, therefore setting a zero model project is possible. Key success factors for disease prevention and control need further study. GM production is suitable for further CCA surveillance and monitoring of the population with a high risk score in this area.
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Yang, Yan; Liu, Yan; He, Jun-Chuang; Wang, Jian-Ming; Schemmer, Peter; Ma, Chao-Qun; Qian, Ya-Wei; Yao, Wei; Zhang, Jian; Qi, Wei-Peng; Fu, Yang; Feng, Wei; Yang, Tao
2016-08-23
Cholangiocarcinoma (CCA) invasion and metastasis are the primary causes of poor survival rates in patients. The epithelial-mesenchymal transition (EMT) is a crucial step in cancer invasion and metastasis. However, it is still unclear of the molecular mechanism. In this study, the expression of 14-3-3ζ and atypical protein kinase C-ι (aPKC-ι) was further detected in CCA tissues and cell lines. Meanwhile, we established the EMT model of CCA cells and investigated 14-3-3ζ and aPKC-ι co-regulatory effect on the EMT in vitro and in vivo. Further, we identified the downstream molecular glycogen synthase kinase 3 beta (GSK-3β)/Snail signalling pathway that contribute to regulating the EMT. Our data showed that the expression of 14-3-3ζ and aPKC-ι was synergistically increased in CCA tissues compared with adjacent noncancerous tissues and was intimately associated with differentiation and the tumour-node-metastasis (TNM) stage. Multivariate Cox regression analysis indicated that high 14-3-3ζ and aPKC-ι expression separately predicted a poor prognosis and were independent prognostic indicators in patients with CCA. The CO-IP experiment confirmed that the mutual binding relationship between 14-3-3ζ and aPKC-ι. Small interfering RNAs and siRNA rescue experiment demonstrated that 14-3-3ζ and aPKC-ι regulated each other. In addition, 14-3-3ζ and aPKC-ι pretreatment by si-RNA inhibit the phosphorylated GSK-3β and Snail expression during EMT. Meanwhile, silence of 14-3-3ζ or aPKC-ι suppressed CCA cells migration, metastasis and proliferation in vitro and in vivo. Our study demonstrates that 14-3-3ζ and aPKC-ι synergistically facilitate EMT of CCA via GSK-3β/Snail signalling pathway, and may be potential therapeutic target for CCA.
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He, Jun-chuang; Wang, Jian-ming; Schemmer, Peter; Ma, Chao-qun; Qian, Ya-wei; Yao, Wei; Zhang, Jian; Qi, Wei-peng; Fu, Yang; Feng, Wei; Yang, Tao
2016-01-01
Cholangiocarcinoma (CCA) invasion and metastasis are the primary causes of poor survival rates in patients. The epithelial-mesenchymal transition (EMT) is a crucial step in cancer invasion and metastasis. However, it is still unclear of the molecular mechanism. In this study, the expression of 14-3-3ζ and atypical protein kinase C-ι (aPKC-ι) was further detected in CCA tissues and cell lines. Meanwhile, we established the EMT model of CCA cells and investigated 14-3-3ζ and aPKC-ι co-regulatory effect on the EMT in vitro and in vivo. Further, we identified the downstream molecular glycogen synthase kinase 3 beta (GSK-3β)/Snail signalling pathway that contribute to regulating the EMT. Our data showed that the expression of 14-3-3ζ and aPKC-ι was synergistically increased in CCA tissues compared with adjacent noncancerous tissues and was intimately associated with differentiation and the tumour-node-metastasis (TNM) stage. Multivariate Cox regression analysis indicated that high 14-3-3ζ and aPKC-ι expression separately predicted a poor prognosis and were independent prognostic indicators in patients with CCA. The CO-IP experiment confirmed that the mutual binding relationship between 14-3-3ζ and aPKC-ι. Small interfering RNAs and siRNA rescue experiment demonstrated that 14-3-3ζ and aPKC-ι regulated each other. In addition, 14-3-3ζ and aPKC-ι pretreatment by si-RNA inhibit the phosphorylated GSK-3β and Snail expression during EMT. Meanwhile, silence of 14-3-3ζ or aPKC-ι suppressed CCA cells migration, metastasis and proliferation in vitro and in vivo. Our study demonstrates that 14-3-3ζ and aPKC-ι synergistically facilitate EMT of CCA via GSK-3β/Snail signalling pathway, and may be potential therapeutic target for CCA. PMID:27409422
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Fractionation of Exosomes and DNA using Size-Based Separation at the Nanoscale
NASA Astrophysics Data System (ADS)
Wunsch, Benjamin; Smith, Joshua; Wang, Chao; Gifford, Stacey; Brink, Markus; Bruce, Robert; Solovitzky, Gustavo; Austin, Robert; Astier, Yann
Exosomes, a key target of ``liquid biopsies'', are nano-vesicles found in nearly all biological fluids. Exosomes are secreted by eukaryotic and prokaryotic cells alike, and contain information about their originating cells, including surface proteins, cytoplasmic proteins, and nucleic acids. One challenge in studying exosome morphology is the difficulty of sorting exosomes by size and surface markers. Common separation techniques for exosomes include ultracentrifugation and ultrafiltration, for preparation of large volume samples, but these techniques often show contamination and significant heterogeneity between preparations. To date, deterministic lateral displacement (DLD) pillar arrays in silicon have proven an efficient technology to sort, separate, and enrich micron-scale particles including human parasites, eukaryotic cells, blood cells, and circulating tumor cells in blood; however, the DLD technology has never been translated to the true nanoscale, where it could function on bio-colloids such as exosomes. We have fabricated nanoscale DLD (nanoDLD) arrays capable of rapidly sorting colloids down to 20 nm in continuous flow, and demonstrated size sorting of individual exosome vesicles and dsDNA polymers, opening the potential for on-chip biomolecule separation and diagnosti
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Rheotaxis of elongated platinum-gold nanoswimmers
NASA Astrophysics Data System (ADS)
Brosseau, Quentin; Wu, Yang; Ristroph, Leif; Zhang, Jun; Ward, Michael; Shelley, Michael
2017-11-01
Directed motion of self-propelled colloids has attracted much attention as a possible means to transport microscopic cargo to desired locations. However, active colloids, such as our gold-platinum (Au-Pt) bi-metallic motors ( 2 micrometers) that are powered by hydrogen peroxide (H2O2), are subjected to Brownian motion and move diffusively. These swimmers can be directed via interactions with structured substrates, e.g. within an array of asymmetric pillars. Our current study focuses on realizing the directed motion in an imposed open flow, of these active nanorods. This dynamic response, often referred to as ``rheotaxis'', is found in many marine organisms. The effect of flow geometry and flow characteristics will be discussed in more details.
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Bouhlel, Jihéne; Jouan-Rimbaud Bouveresse, Delphine; Abouelkaram, Said; Baéza, Elisabeth; Jondreville, Catherine; Travel, Angélique; Ratel, Jérémy; Engel, Erwan; Rutledge, Douglas N
2018-02-01
The aim of this work is to compare a novel exploratory chemometrics method, Common Components Analysis (CCA), with Principal Components Analysis (PCA) and Independent Components Analysis (ICA). CCA consists in adapting the multi-block statistical method known as Common Components and Specific Weights Analysis (CCSWA or ComDim) by applying it to a single data matrix, with one variable per block. As an application, the three methods were applied to SPME-GC-MS volatolomic signatures of livers in an attempt to reveal volatile organic compounds (VOCs) markers of chicken exposure to different types of micropollutants. An application of CCA to the initial SPME-GC-MS data revealed a drift in the sample Scores along CC2, as a function of injection order, probably resulting from time-related evolution in the instrument. This drift was eliminated by orthogonalization of the data set with respect to CC2, and the resulting data are used as the orthogonalized data input into each of the three methods. Since the first step in CCA is to norm-scale all the variables, preliminary data scaling has no effect on the results, so that CCA was applied only to orthogonalized SPME-GC-MS data, while, PCA and ICA were applied to the "orthogonalized", "orthogonalized and Pareto-scaled", and "orthogonalized and autoscaled" data. The comparison showed that PCA results were highly dependent on the scaling of variables, contrary to ICA where the data scaling did not have a strong influence. Nevertheless, for both PCA and ICA the clearest separations of exposed groups were obtained after autoscaling of variables. The main part of this work was to compare the CCA results using the orthogonalized data with those obtained with PCA and ICA applied to orthogonalized and autoscaled variables. The clearest separations of exposed chicken groups were obtained by CCA. CCA Loadings also clearly identified the variables contributing most to the Common Components giving separations. The PCA Loadings did not highlight the most influencing variables for each separation, whereas the ICA Loadings highlighted the same variables as did CCA. This study shows the potential of CCA for the extraction of pertinent information from a data matrix, using a procedure based on an original optimisation criterion, to produce results that are complementary, and in some cases may be superior, to those of PCA and ICA. Copyright © 2017 Elsevier B.V. All rights reserved.
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Jambeck, Jenna; Weitz, Keith; Solo-Gabriele, Helena; Townsend, Timothy; Thorneloe, Susan
2007-01-01
Chromated copper arsenate (CCA)-treated wood is a preservative treated wood construction product that grew in use in the 1970s for both residential and industrial applications. Although some countries have banned the use of the product for some applications, others have not, and the product continues to enter the waste stream from construction, demolition and remodeling projects. CCA-treated wood as a solid waste is managed in various ways throughout the world. In the US, CCA-treated wood is disposed primarily within landfills; however some of the wood is combusted in waste-to-energy (WTE) facilities. In other countries, the predominant disposal option for wood, sometimes including CCA-treated wood, is combustion for the production of energy. This paper presents an estimate of the quantity of CCA-treated wood entering the disposal stream in the US, as well as an examination of the trade-offs between landfilling and WTE combustion of CCA-treated wood through a life-cycle assessment and decision support tool (MSW DST). Based upon production statistics, the estimated life span and the phaseout of CCA-treated wood, recent disposal projections estimate the peak US disposal rate to occur in 2008, at 9.7 million m(3). CCA-treated wood, when disposed with construction and demolition (C&D) debris and municipal solid waste (MSW), has been found to increase arsenic and chromium concentrations in leachate. For this reason, and because MSW landfills are lined, MSW landfills have been recommended as a preferred disposal option over unlined C&D debris landfills. Between landfilling and WTE for the same mass of CCA-treated wood, WTE is more expensive (nearly twice the cost), but when operated in accordance with US Environmental Protection Agency (US EPA) regulations, it produces energy and does not emit fossil carbon emissions. If the wood is managed via WTE, less landfill area is required, which could be an influential trade-off in some countries. Although metals are concentrated in the ash in the WTE scenario, the MSW landfill scenario releases a greater amount of arsenic from leachate in a more dilute form. The WTE scenario releases more chromium from the ash on an annual basis. The WTE facility and subsequent ash disposal greatly concentrates the chromium, often oxidizing it to the more toxic and mobile Cr(VI) form. Elevated arsenic and chromium concentrations in the ash leachate may increase leachate management costs.
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Treated wood preservatives linked to aquatic damage, human illness, and death--a societal problem.
Edlich, Richard F; Winters, Kathryne L; Long, William B
2005-01-01
On February 12, 2002, the US Environmental Protection Agency (EPA) announced a voluntary decision by industry to move consumer use of treated lumber products away from a variety of pressure-treated wood that contains arsenate (As) by December 31, 2003, in favor of new alternative wood preservatives. Chromated copper arsenate (CCA) is a chemical mixture consisting of three pesticidal compounds (As, chromium, and copper) registered for wood preservative uses. CCA is injected into wood by a process that uses high pressure to saturate wood products with the chemical. Only people who have received the proper safety training should use CCA to treat wood products. Around the home, CCA-treated wood is commonly used for decks, walkways, fences, gazebos, boat docks, and playground equipment. Other common uses of CCA-treated wood include highway noise barriers, sign posts, utility posts, and retaining walls. As of January 1, 2004, the EPA is no longer allowing CCA products to be used to treat wood intended for any of these residential uses. This decision will facilitate the voluntary transition to new alternative wood preservatives that do not contain As in both the manufacturing and retail sectors. To its credit, the EPA has developed consumer safety information sheets, hanging signs, end signs, and bin stickers that provide comprehensive information about the dangers of CCA-treated wood, use-site, and handling precautions. The EPA has not concluded that CCA-treated wood poses any unreasonable risk to the public or the environment. Nevertheless, As is a known human carcinogen and, thus, the EPA believes that any reduction in the levels of potential exposure to As is desirable. The toxicologic manifestations have been primarily related to the effects of As exposure from drinking water sources and include the following: acute poisoning incidents, cardiovascular effects, diabetes mellitus, and cancer. Understanding the biomethylation of As is central to elucidating its action as a toxin and a carcinogen. In humans as in many other species, inorganic As is enzymatically converted to the methylated products methyl As (MAs) and dimethyl As (DMAs). The aforementioned voluntary agreement to reduce the uses of CCA-treated wood does not include a ban on the use of CCA for residential roofing. A major reason that this wood product should be banned from residential roofing is that it does not provide a Class "A" fire-rated roof system, which markedly reduce the frequency of residential roof fires.
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Transgenic plants expressing GLK1 and CCA1 having increased nitrogen assimilation capacity
Coruzzi, Gloria [New York, NY; Gutierrez, Rodrigo A [Santiago, CL; Nero, Damion C [Woodside, NY
2012-04-10
Provided herein are compositions and methods for producing transgenic plants. In specific embodiments, transgenic plants comprise a construct comprising a polynucleotide encoding CCA1, GLK1 or bZIP1, operably linked to a plant-specific promote, wherein the CCA1, GLK1 or bZIP1 is ectopically overexpressed in the transgenic plants, and wherein the promoter is optionally a constitutive or inducible promoter. In other embodiments, transgenic plants in which express a lower level of CCA1, GLK1 or bZIP1 are provided. Also provided herein are commercial products (e.g., pulp, paper, paper products, or lumber) derived from the transgenic plants (e.g., transgenic trees) produced using the methods provided herein.
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Silveira, Alda Maria Soares; Costa, Emanuele Gama Dutra; Ray, Debalina; Suzuki, Brian M.; Hsieh, Michael H.; Fraga, Lucia Alves de Oliveira; Caffrey, Conor R.
2016-01-01
Background The Kato-Katz (KK) stool smear is the standard test for the diagnosis of Schistosoma mansoni infection, but suffers from low sensitivity when infections intensities are moderate to low. Thus, misdiagnosed individuals remain untreated and contribute to the disease transmission, thereby forestalling public health efforts to move from a modality of disease control to one of elimination. As an alternative, the urine-based diagnosis of schistosomiasis mansoni via the circulating cathodic antigen immuno-chromatographic test (CCA-ICT) has been extensively evaluated in Africa with the conclusion that it may replace the KK test in areas where prevalences are moderate or high. Methods and Findings The objective was to measure the performance of the CCA-ICT in a sample study population composed of residents from non-endemic and endemic areas for schistosomiasis mansoni in two municipalities of Minas Gerais state, Brazil. Volunteers (130) were classified into three infection status groups based on duplicate Kato-Katz thick smears from one stool sample (2KK test): 41 negative individuals from non-endemic areas, 41 negative individuals from endemic areas and 48 infected individuals from endemic areas. Infection status was also determined by the CCA-ICT and infection exposure by antibody ELISA (enzyme-linked immunosorbent assay) to S. mansoni soluble egg antigen (SEA) and soluble (adult) worm antigen preparation (SWAP). Sensitivity and specificity were influenced by whether the trace score visually adjudicated in the CCA-ICT was characterized as positive or negative for S. mansoni infection. An analysis of a two-graph receiver operating characteristic was performed to change the cutoff point. When the trace score was interpreted as a positive rather than as a negative result, the specificity decreased from 97.6% to 78.0% whereas sensitivity increased from 68.7% to 85.4%. A significantly positive correlation between the CCA-ICT scores and egg counts was identified (r = 0.6252, p = 0.0001). However, the CCA-ICT misdiagnosed as negative 14.6% of 2KK positive individuals, predominantly those with light infections (fewer than 100 eggs/g feces). Considering 2KK as reference test, the discriminating power of the CCA-ICT (the area under the curve [AUC] = 0.817) was greater than the SEA-ELISA (AUC = 0.744) and SWAP-ELISA (AUC = 0.704). Conclusion Our data for the performance of the CCA-ICT in the Brazilian communities endemic for schistosomiasis mansoni support those from Africa, i.e., in areas with greater infection prevalence and intensities, the CCA-ICT may be useful as a tool to indicate community-based preventative chemotherapy without individual diagnosis. However, because of the Brazilian Ministry of Health’s recommendation for individual diagnosis in areas where prevalence is less than 15%, i.e., those areas in which infection intensities are likely to be lowest, the CCA-ICT lacks the sensitivity to be used as standalone diagnostic tool. PMID:26752073
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Gijsen, Frank J.; Marquering, Henk; van Ooij, Pim; vanBavel, Ed; Wentzel, Jolanda J.; Nederveen, Aart J.
2016-01-01
Introduction Wall shear stress (WSS) and oscillatory shear index (OSI) are associated with atherosclerotic disease. Both parameters are derived from blood velocities, which can be measured with phase-contrast MRI (PC-MRI). Limitations in spatiotemporal resolution of PC-MRI are known to affect these measurements. Our aim was to investigate the effect of spatiotemporal resolution using a carotid artery phantom. Methods A carotid artery phantom was connected to a flow set-up supplying pulsatile flow. MRI measurement planes were placed at the common carotid artery (CCA) and internal carotid artery (ICA). Two-dimensional PC-MRI measurements were performed with thirty different spatiotemporal resolution settings. The MRI flow measurement was validated with ultrasound probe measurements. Mean flow, peak flow, flow waveform, WSS and OSI were compared for these spatiotemporal resolutions using regression analysis. The slopes of the regression lines were reported in %/mm and %/100ms. The distribution of low and high WSS and OSI was compared between different spatiotemporal resolutions. Results The mean PC-MRI CCA flow (2.5±0.2mL/s) agreed with the ultrasound probe measurements (2.7±0.02mL/s). Mean flow (mL/s) depended only on spatial resolution (CCA:-13%/mm, ICA:-49%/mm). Peak flow (mL/s) depended on both spatial (CCA:-13%/mm, ICA:-17%/mm) and temporal resolution (CCA:-19%/100ms, ICA:-24%/100ms). Mean WSS (Pa) was in inverse relationship only with spatial resolution (CCA:-19%/mm, ICA:-33%/mm). OSI was dependent on spatial resolution for CCA (-26%/mm) and temporal resolution for ICA (-16%/100ms). The regions of low and high WSS and OSI matched for most of the spatiotemporal resolutions (CCA:30/30, ICA:28/30 cases for WSS; CCA:23/30, ICA:29/30 cases for OSI). Conclusion We show that both mean flow and mean WSS are independent of temporal resolution. Peak flow and OSI are dependent on both spatial and temporal resolution. However, the magnitude of mean and peak flow, WSS and OSI, and the spatial distribution of OSI and WSS did not exhibit a strong dependency on spatiotemporal resolution. PMID:27669568
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NASA Astrophysics Data System (ADS)
Scafetta, Nicola
2018-07-01
Holm (ASR, 2018) claims that Scafetta (ASR 57, 2121-2135, 2016) is "irreproducible" because I would have left "undocumented" the values of two parameters (a reduced-rank index p and a regularization term δ) that he claimed to be requested in the Magnitude Squared Coherence Canonical Correlation Analysis (MSC-CCA). Yet, my analysis did not require such two parameters. In fact: (1) using the MSC-CCA reduced-rank option neither changes the result nor was needed since Scafetta (2016) statistically evaluated the significance of the coherence spectral peaks; (2) the analysis algorithm neither contains nor needed the regularization term δ . Herein I show that Holm could not replicate Scafetta (2016) because he used different analysis algorithms. In fact, although Holm claimed to be using MSC-CCA, for his Figs. 2-4 he used a MatLab code labeled "gcs_cca_1D.m" (see paragraph 2 of his Section 3), which Holm also modified, that implements a different methodology known as the Generalized Coherence Spectrum using the Canonical Correlation Analysis (GCS-CCA). This code is herein demonstrated to be unreliable under specific statistical circumstances such as those required to replicate Scafetta (2016). On the contrary, the MSC-CCA method is stable and reliable. Moreover, Holm could not replicate my result also in his Fig. 5 because there he used the basic Welch MSC algorithm by erroneously equating it to MSC-CCA. Herein I clarify step-by-step how to proceed with the correct analysis, and I fully confirm the 95% significance of my results. I add data and codes to easily replicate my results.
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Nakanuma, Yasuni; Uchida, Tsuneyuki; Sato, Yasunori; Uesaka, Katsuhiko
2017-02-01
Nodular-sclerosing cholangiocarcinoma (NS-CCA) is a common CCA of the intrahepatic large, perihilar, and distal bile ducts. Intraepithelial biliary neoplasms, such as the mucosal extension of carcinoma and preinvasive neoplastic lesions (ie, biliary intraepithelial neoplasia) reportedly occur in the bile ducts around CCA. In the present study, we collectively refer to these intraepithelial lesions as "intraepithelial neoplasms of the bile duct (IENBs)". We examined the IENBs in 57 surgically resected cases of NS-CCA. S100P immunostaining was used to help detect IENBs. The IENBs formed field(s) of continuous neoplastic biliary epithelial cells and showed a flat, micropapillary, or papillotubular configuration. IENBs could be classified into 3 categories based on their atypia: group A (neoplastic but not enough for malignancy), B (neoplastic and sufficiently well differentiated for high-grade dysplasia), and C (overtly malignant and variably differentiated). IENB was found in 31 of 57 cases, with group C the most common (26 cases) followed by group B (22 cases) and group A (16 cases). The expression of cancer-related molecules and MIB-1 index of groups A and B differed from those of invasive CCA, whereas these features of group C were relatively similar to those of invasive CCA. In conclusion, IENB was not infrequently found in NS-CCA and could be classified into 3 grades. Preinvasive lesions (biliary intraepithelial neoplasias) are likely to be found in groups A and B, whereas cancerization would be included in group C. The classification of IENB may be useful for future studies of the preinvasive intraepithelial neoplastic lesions of NS-CCAs. Copyright © 2016. Published by Elsevier Inc.
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NASA Astrophysics Data System (ADS)
Mubaya, C. P.; Ngepah, N.; Seyama, W.
2015-12-01
Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR) have similar aims and mutual benefits, and there is a very strong rationale for adopting a more integrated approach to these issues rather than analysing each of them as distinct from the other. One of the gaps that have been noted in this context is the lack of evidence in systematic integration of CCA and DRR in Southern Africa. In this regard, this study builds on understanding CCA and DRR policies from the perspectives of vulnerable groups- women and smallholder farmers, and conducts institutional and policy analysis of CCA and DRR in southern Africa, with specific focus on Malawi and Zimbabwe. Both quantitative and qualitative methodologies were employed to collect data for this study in the two countries. The analysis is centred on the conceptualization of DRR in the context of recovery time and CCA on livelihood changes. Findings of the study show that drought is no longer viewed as a hazard as it is a perennial and chronic occurrence in selected climate hotspots, with heightened intensity in certain identified years. Households are able to quickly recover from slow onset hazards such as droughts and dry spells more than they are able to recover from sudden onset floods, implying more capacity towards CCA than DRR. Government programmes and policies are also focused more on CCA than on DRR efforts that appear not to be a priority. Findings point towards female vulnerability from perceptions and practice where males tend to dominate where they are set to benefit from external assistance. We need to strengthen government capacity in implementation of DRR programmes, which is currently limited and development initiatives must deliberately target building the resilience of women.
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Soil arsenic surveys of New Orleans: localized hazards in children's play areas.
Mielke, Howard W; Gonzales, Chris R; Cahn, Elise; Brumfield, Jessica; Powell, Eric T; Mielke, Paul W
2010-10-01
Arsenic (As) ranks first on the 2005 and 2007 hazardous substances priority lists compiled for the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This study describes two New Orleans soil As surveys: (1) a survey of composite soil samples from 286 census tracts and (2) a field survey of soil As at 38 play areas associated with the presence of chromated-copper-arsenate (CCA)-treated wood on residential and public properties. The survey of metropolitan New Orleans soils revealed a median As content of 1.5 mg/kg (range <0.2-16.4) and no distinctive differences between the soils of the city core and outlying areas. Play area accessible soils associated with CCA-treated wood (N = 32) had a median As of 57 mg/kg and 78% of the samples were ≥12 mg/kg, the Louisiana soil As standard. The field survey of play areas for CCA-treated wood (N = 132 samples at 38 sites) was conducted with a portable energy-dispersive X-ray fluorescence (XRF) analyzer. Seventy-five of 132 wood samples (56.8%) were deemed CCA-treated wood. Of the 38 play areas surveyed, 14 (36.8%) had CCA-treated wood. A significant association (Fisher's exact p-value = 0.348 × 10(-6)) was found between CCA-treated wood and soil As (N = 75). At one elementary school CCA-treated woodchips (As range 813-1,654 mg As/kg) covered the playgrounds. The situation in New Orleans probably exists in play areas across the nation. These findings support a precautionary program for testing soils and wood for hazardous substances at all play areas intended for children.
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KHAN, BERNINE I.; JAMBECK, JENNA; SOLO-GABRIELE, HELENA M.; TOWNSEND, TIMOTHY G.; CAI, YONG
2008-01-01
Wood treated with chromated copper arsenate (CCA) is primarily disposed within construction and demolition (C&D) debris landfills, with wood monofills and municipal solid waste (MSW) landfills as alternative disposal options. This study evaluated the extent and speciation of arsenic leaching from landfills containing CCA-treated wood. In control lysimeters where untreated wood was used, DMAA represented the major arsenic species. The dominant arsenic species differed in the lysimeters containing CCA-treated wood, with As(V) greatest in the monofill and C&D lysimeters and As(III) greatest in the MSW lysimeters. In CCA-containing lysimeters, the organoarsenic species MMAA and DMAA were virtually absent in the monofill lysimeter and observed in the C&D and MSW lysimeters. Overall arsenic leaching rate varied for the wood monofill (0.69% per meter of water added), C&D (0.36% per m), and MSW (0.84% per m) lysimeters. Utilizing these rates with annual disposal data, a mathematical model was developed to quantify arsenic leaching from CCA-treated wood disposed to Florida landfills. Model findings showed between 20 to 50 metric tons of arsenic (depending on lysimeter type) had leached prior to 2000 with an expected increase between 350 to 830 metric tons by 2040. Groundwater analysis from 21 Florida C&D landfills suspected of accepting CCA-treated wood showed that groundwater at 3 landfills were characterized by elevated arsenic concentrations with only 1 showing impacts from the C&D waste. The slow release of arsenic from disposed treated wood may account for the lack of significant impact to groundwater near most C&D facilities at this time. However, greater impacts are anticipated in the future given that the maximum releases of arsenic are expected by the year 2100. PMID:16509348
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Real-time quantitative fluorescence measurement of microscale cell culture analog systems
NASA Astrophysics Data System (ADS)
Oh, Taek-il; Kim, Donghyun; Tatosian, Daniel; Sung, Jong Hwan; Shuler, Michael
2007-02-01
A microscale cell culture analog (μCCA) is a cell-based lab-on-a-chip assay that, as an animal surrogate, is applied to pharmacological studies for toxicology tests. A μCCA typically comprises multiple chambers and microfluidics that connect the chambers, which represent animal organs and blood flow to mimic animal metabolism more realistically. A μCCA is expected to provide a tool for high-throughput drug discovery. Previously, a portable fluorescence detection system was investigated for a single μCCA device in real-time. In this study, we present a fluorescence-based imaging system that provides quantitative real-time data of the metabolic interactions in μCCAs with an emphasis on measuring multiple μCCA samples simultaneously for high-throughput screening. The detection system is based on discrete optics components, with a high-power LED and a charge-coupled device (CCD) camera as a light source and a detector, for monitoring cellular status on the chambers of each μCCA sample. Multiple samples are characterized mechanically on a motorized linear stage, which is fully-automated. Each μCCA sample has four chambers, where cell lines MES-SA/DX- 5, and MES-SA (tumor cells of human uterus) have been cultured. All cell-lines have been transfected to express the fusion protein H2B-GFP, which is a human histone protein fused at the amino terminus to EGFP. As a model cytotoxic drug, 10 μM doxorubicin (DOX) was used. Real-time quantitative data of the intensity loss of enhanced green fluorescent protein (EGFP) during cell death of target cells have been collected over several minutes to 40 hours. Design issues and improvements are also discussed.
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Yan, Huan; Li, Hong; Zhu, Linlin; Gao, Junjun; Li, Pengyun; Zhang, Zhan
2018-03-25
Increased inflammation is considered as a risk factor and a promoter of preterm birth (PTB). Monocytes and neutrophils are the main sources of cytokines in the early inflammatory phase. So far, very few studies have indicated CD14/TLR4 and TREM-1 on the monocytes and neutrophils as important targets in PTB. TLR4 and TREM-1 on CD14 + maternal and cord blood monocytes and neutrophils were detected using flow cytometry in 48 normal term women, 48 PTB with chorioamnionitis (CCA) women, and 40 PTB without CCA women. In the fetal membranes, mRNA and protein levels of the CD14/TLR4-TREM-1 signaling pathway, CD14, TLR4, NF-κBp65, and TREM-1 were analyzed by qRT-PCR and western blot. ELISA was further used to detect TLR4 and TREM-1 levels in maternal and cord serums. Compared with the normal term and PTB without CCA women, we found that (1) TLR4 and TREM-1 levels on CD14 + maternal and cord blood monocytes and neutrophils in the PTB with CCA group were elevated (p < .001); (2) the protein and mRNA expressions of CA14, TLR4, NF-κBp65, and TREM-1 of the PTB with CCA group were upregulated (p < .001); (3) Maternal and cord serum concentrations of TLR4 and TREM-1 in the PTB with CCA group were greater (p < .001). The high levels of TLR4 and TREM-1 surface expression were observed on CD14 + maternal and cord blood monocyte and neutrophils, confirming their proinflammatory profiles in PTB with CCA. TLR4 and TREM-1 on monocyte and neutrophils might have a role in infection-related PTB.
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Kamarajah, Sivesh K
2018-03-07
Recently, the AJCC has released its 8th edition changes to the staging system for intrahepatic cholangiocarcinoma (iCCA). This study sought to validate the proposed changes to the 8th edition of AJCC system for T and N classification of iCCA using a population-based data set. Using the Surveillance, Epidemiology, and End Results (SEER) database (1998-2013), patients undergoing resection or non-surgical management for non-metastatic iCCA were identified. Overall survival was estimated using the Kaplan-Meier method and compared using log-rank tests. Concordance indices (c-indices) calculated from Cox proportional hazards models were calculated to evaluate discriminatory power. The study included 2630 patients resected (37%) or non-surgically managed (63%) for iCCA. Nodal staging was performed in 56%, of whom 31% had positive nodes. For all patients with iCCA, the median 5-year survival by AJCC T classification for T1a, T1b, T2, T3, and T4 was 32, 21, 14, 10, and 10 months, respectively (p < 0.001). The concordance index for the staging system was 0.57 for all patients, 0.62 for those who underwent resection, and 0.54 for patients who did not undergo resection. In summary, the new AJCC 8th edition staging system is comparable to the 7th edition and valid in stratifying patients with iCCA. However, the performance of the staging system is better in patients undergoing surgical resection than those undergoing non-surgical management. These findings further highlight the need for improved accuracy of radiological imaging in clinically staging patients to guide prognosis.
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Patterning of colloidal particles in the galvanic microreactor
NASA Astrophysics Data System (ADS)
Jan, Linda
A Cu-Au galvanic microreactor is used to demonstrate the autonomous patterning of two-dimensional colloidal crystals with spatial and orientational order which are adherent to the electrode substrate. The microreactor is comprised of a patterned array of copper and gold microelectrodes in a coplanar arrangement that is immersed in a dilute hydrochloric acid solution in which colloidal polystyrene microspheres are suspended. During the electrochemical dissolution of copper, polystyrene colloids are transported to the copper electrodes. The spatial arrangement of the electrodes determines whether the colloids initiate aggregation at the edges or centers of the copper electrodes. Depending on the microreactor parameters, two-dimensional colloidal crystals can form and adhere to the electrode. This thesis investigates the mechanisms governing the autonomous particle motion, the directed particle trajectory (inner- versus edge-aggregation) as affected by the spatial patterning of the electrodes, and the adherence of the colloidal particles onto the substrate. Using in situ current density measurements, particle velocimetry, and order-of-magnitude arguments, it is shown that particle motion is governed by bulk fluid motion and electrophoresis induced by the electrochemical reactions. Bulk electrolyte flow is most likely driven by electrochemical potential gradients of reaction products formed during the inhomogeneous copper dissolution, particularly due to localized high current density at the electrode junction. Preferential aggregation of the colloidal particles resulting in inner- and edge-aggregation is influenced by changes to the flow pattern in response to difference in current density profiles as affected by the spatial patterning of the electrode. Finally, by determining the onset of particle cementation through particle tracking analysis, and by monitoring the deposition of reaction products through the observation of color changes of the galvanic electrodes in situ, it is shown that particle cementation coincides with the precipitation and deposition of reaction products. The precipitation process is caused by shifts in the chemical equilibria of the microreactor due to changes in the composition of the electrolyte during the reactions, which can be used to control particle cementation. The corrosion driven transport, deposition and adherence of colloidal particles at corrosion sites have implications for the development of autonomous self-healing materials.
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Xu, Yi; Wang, Zhidong; Jiang, Xingming; Cui, Yunfu
2017-08-01
Cholangiocarcinoma (CCA) is a deadly disease that poorly responds to chemotherapy and radiotherapy and whose incidence has increased worldwide. Furthermore, long noncoding RNAs (lncRNAs) play important roles in multiple biological processes, including tumorigenesis. Specifically, H19, the first discovered lncRNA, has been reported to be overexpressed in diverse human carcinomas, but the overall biological role and clinical significance of H19 in CCA remains unknown. In the present study, expression levels of H19 were investigated in CCA tissues and cell lines and were correlated with clinicopathological features. Moreover, we explored the functional roles of H19 depletion in QBC939 and RBE cells, including cell proliferation, apoptosis, migration, invasion and epithelial-to-mesenchymal transition (EMT). The results indicated that H19 was upregulated in CCA tissue samples and cell lines, and this upregulation was associated with tumor size, TNM stage, postoperative recurrence and overall survival in 56 patients with CCA. Moreover, knockdown of H19 followed by RNA silencing restrained cell proliferation and promoted apoptosis. In addition, H19 suppression impaired migration and invasion potential by reversing EMT. Overall, our findings may help to develop diagnostic biomarkers and therapeutics that target H19 for the treatment of CCA. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
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Multi-scale sampling to evaluate assemblage dynamics in an oceanic marine reserve.
Thompson, Andrew R; Watson, William; McClatchie, Sam; Weber, Edward D
2012-01-01
To resolve the capacity of Marine Protected Areas (MPA) to enhance fish productivity it is first necessary to understand how environmental conditions affect the distribution and abundance of fishes independent of potential reserve effects. Baseline fish production was examined from 2002-2004 through ichthyoplankton sampling in a large (10,878 km(2)) Southern Californian oceanic marine reserve, the Cowcod Conservation Area (CCA) that was established in 2001, and the Southern California Bight as a whole (238,000 km(2) CalCOFI sampling domain). The CCA assemblage changed through time as the importance of oceanic-pelagic species decreased between 2002 (La Niña) and 2003 (El Niño) and then increased in 2004 (El Niño), while oceanic species and rockfishes displayed the opposite pattern. By contrast, the CalCOFI assemblage was relatively stable through time. Depth, temperature, and zooplankton explained more of the variability in assemblage structure at the CalCOFI scale than they did at the CCA scale. CalCOFI sampling revealed that oceanic species impinged upon the CCA between 2002 and 2003 in association with warmer offshore waters, thus explaining the increased influence of these species in the CCA during the El Nino years. Multi-scale, spatially explicit sampling and analysis was necessary to interpret assemblage dynamics in the CCA and likely will be needed to evaluate other focal oceanic marine reserves throughout the world.
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Winkelmann, Ria; Schneider, Markus; Hartmann, Sylvia; Schnitzbauer, Andreas A; Zeuzem, Stefan; Peveling-Oberhag, Jan; Hansmann, Martin Leo; Walter, Dirk
2018-05-09
Immune-modulating therapy is a promising therapy for patients with cholangiocarcinoma (CCA). Microsatellite instability (MSI) might be a favorable predictor for treatment response, but comprehensive data on the prevalence of MSI in CCA are missing. The aim of the current study was to determine the prevalence of MSI in a German tertiary care hospital. Formalin-fixed paraffin-embedded tissue samples, obtained in the study period from 2007 to 2015 from patients with CCA undergoing surgical resection with curative intention at Johann Wolfgang Goethe University hospital, were examined. All samples were investigated immunohistochemically for the presence of MSI (expression of MLH1, PMS2, MSH2, and MSH6) as well as by pentaplex polymerase chain reaction for five quasimonomorphic mononucleotide repeats ( BAT-25 , BAT-26 , NR-21 , NR-22 , and NR-24 ). In total, 102 patients were included, presenting intrahepatic ( n = 35, 34.3%), perihilar ( n = 42, 41.2%), and distal CCA ( n = 25, 24.5%). In the immunohistochemical analysis, no loss of expression of DNA repair enzymes was observed. In the PCR-based analysis, one out of 102 patients was found to be MSI-high and one out of 102 was found to be MSI-low. Thus, MSI seems to appear rarely in CCA in Germany. This should be considered when planning immune-modulating therapy trials for patients with CCA.
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Alvaro, Domenico; Cannizzaro, Renato; Labianca, Roberto; Valvo, Francesca; Farinati, Fabio
2010-12-01
The incidence of Cholangiocellular carcinoma (CCA) is increasing, due to a sharp increase of the intra-hepatic form. Evidence-ascertained risk factors for CCA are primary sclerosing cholangitis, Opistorchis viverrini infection, Caroli disease, congenital choledocal cist, Vater ampulla adenoma, bile duct adenoma and intra-hepatic lithiasis. Obesity, diabetes, smoking, abnormal biliary-pancreatic junction, bilio-enteric surgery, and viral cirrhosis are emerging risk factors, but their role still needs to be validated. Patients with primary sclerosing cholangitis should undergo surveillance, even though a survival benefit has not been clearly demonstrated. CCA is most often diagnosed in an advanced stage, when therapeutic options are limited to palliation. Diagnosis of the tumor is often difficult and multiple imaging techniques should be used, particularly for staging. Surgery is the standard of care for resectable CCA, whilst liver transplantation should be considered only in experimental settings. Metal stenting is the standard of care in inoperable patients with an expected survival >4 months. Gemcitabine or platinum analogues are recommended in advanced CCA whilst there are no validated neo-adjuvant treatments or second-line chemotherapies. Even though promising results have been obtained in CCA with radiotherapy, further randomized controlled trials are needed. Copyright © 2010 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
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Role of the CCA bulge of prohead RNA of bacteriophage ø29 in DNA packaging.
Zhao, Wei; Morais, Marc C; Anderson, Dwight L; Jardine, Paul J; Grimes, Shelley
2008-11-14
The oligomeric ring of prohead RNA (pRNA) is an essential component of the ATP-driven DNA packaging motor of bacteriophage ø29. The A-helix of pRNA binds the DNA translocating ATPase gp16 (gene product 16) and the CCA bulge in this helix is essential for DNA packaging in vitro. Mutation of the bulge by base substitution or deletion showed that the size of the bulge, rather than its sequence, is primary in DNA packaging activity. Proheads reconstituted with CCA bulge mutant pRNAs bound the packaging ATPase gp16 and the packaging substrate DNA-gp3, although DNA translocation was not detected with several mutants. Prohead/bulge-mutant pRNA complexes with low packaging activity had a higher rate of ATP hydrolysis per base pair of DNA packaged than proheads with wild-type pRNA. Cryoelectron microscopy three-dimensional reconstruction of proheads reconstituted with a CCA deletion pRNA showed that the protruding pRNA spokes of the motor occupy a different position relative to the head when compared to particles with wild-type pRNA. Therefore, the CCA bulge seems to dictate the orientation of the pRNA spokes. The conformational changes observed for this mutant pRNA may affect gp16 conformation and/or subsequent ATPase-DNA interaction and, consequently, explain the decreased packaging activity observed for CCA mutants.
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Multi-Scale Sampling to Evaluate Assemblage Dynamics in an Oceanic Marine Reserve
Thompson, Andrew R.; Watson, William; McClatchie, Sam; Weber, Edward D.
2012-01-01
To resolve the capacity of Marine Protected Areas (MPA) to enhance fish productivity it is first necessary to understand how environmental conditions affect the distribution and abundance of fishes independent of potential reserve effects. Baseline fish production was examined from 2002–2004 through ichthyoplankton sampling in a large (10,878 km2) Southern Californian oceanic marine reserve, the Cowcod Conservation Area (CCA) that was established in 2001, and the Southern California Bight as a whole (238,000 km2 CalCOFI sampling domain). The CCA assemblage changed through time as the importance of oceanic-pelagic species decreased between 2002 (La Niña) and 2003 (El Niño) and then increased in 2004 (El Niño), while oceanic species and rockfishes displayed the opposite pattern. By contrast, the CalCOFI assemblage was relatively stable through time. Depth, temperature, and zooplankton explained more of the variability in assemblage structure at the CalCOFI scale than they did at the CCA scale. CalCOFI sampling revealed that oceanic species impinged upon the CCA between 2002 and 2003 in association with warmer offshore waters, thus explaining the increased influence of these species in the CCA during the El Nino years. Multi-scale, spatially explicit sampling and analysis was necessary to interpret assemblage dynamics in the CCA and likely will be needed to evaluate other focal oceanic marine reserves throughout the world. PMID:22448236
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Kim, Nayoung; Lee, Sang Hyub; Son, Jun Hyuk; Lee, Jae Min; Kang, Min-Jung; Kim, Bo Hye; Lee, Jung-Su; Ryu, Ji Kon; Kim, Yong-Tae
2016-11-01
Cholangiocarcinoma (CCA) is a malignancy with poor prognosis and limited therapeutic options. Effective prevention and treatment of CCA require developing novel anticancer agents and improved therapeutic regimens. As natural products are concidered a rich source of potential anticancer agents, we investigated the anticancer effect of fisetin in combination with gemcitabine. Cytotoxic effect of fisetin and gemcitabine on a human CCA cell line SNU-308 was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and apoptosis assay using propidium iodine and annexin V. Molecular mechanisms of fisetin action in CCA were investigated by western blotting. Fisetin was found to inhibit survival of CCA cells, through strongly phosphorylating ERK. It also induced cellular apoptosis additively in combination with gemcitabine. Expression of cellular proliferative markers, such as phospho-p65 and myelocytomatosis (MYC), were reduced by fisetin. These results suggest fisetin in combination with gemcitabine as a candidate for use in improved anticancer regimens. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
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Facciuto, Marcelo E; Singh, Manoj K; Lubezky, Nir; Selim, Motaz A; Robinson, Dorothy; Kim-Schluger, Leona; Florman, Sander; Ward, Stephen C; Thung, Swan N; Fiel, MariaIsabel; Schiano, Thomas D
2015-01-01
The role of liver transplantation (LT) in the management of cirrhotic patients with tumors exhibiting intrahepatic bile duct differentiation remains controversial. The objective of this study was to characterize the spectrum of these tumors and analyze post-LT outcomes. Retrospective pathology database search of explant histology analysis of liver transplants between April 1993 and November 2013. Thirty-two patients were analyzed, 75% were men with a mean age of 60 years. Seven patients had nodules demonstrating intrahepatic cholangiocarcinoma (I-CCA), nine had I-CCA nodules occurring concomitantly with hepatocellular carcinoma (HCC), and 16 had mixed HCC-CCA nodules. The median number of tumors was 1 and size was 2.5 cm. Overall patient survival post-LT at 1 and 5 years was 71% and 57%, respectively. Patients within Milan criteria, especially with I-CCA features, showed a 5-year tumor recurrence rate (10%) and 5-year survival rate (78%) comparable with other patients having HCC within Milan criteria. This series showed that patients with CCA within Milan criteria may be able to achieve acceptable long-term post-LT survival.
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Kawamoto, Makoto; Umebayashi, Masayo; Tanaka, Hiroto; Koya, Norihiro; Nakagawa, Sinichiro; Kawabe, Ken; Onishi, Hideya; Nakamura, Masafumi; Morisaki, Takashi
2018-05-01
Metronidazole (MNZ) is a common antibiotic that exerts disulfiram-like effects when taken together with alcohol. However, the relationship between MNZ and aldehyde dehydrogenase (ALDH) activity remains unclear. This study investigated whether MNZ reduces cancer stemness by suppressing ALDH activity and accordingly reducing the malignancy of cholangiocarcinoma (CCA). We developed gemcitabine (GEM)-resistant TFK-1 cells and originally established CCA cell line from a patient with GEM-resistant CCA. Using these cell lines, we analyzed the impacts of MNZ for cancer stem cell markers, invasiveness, and chemosensitivity. MNZ reduced ALDH activity in GEM-resistant CCA cells, leading to decreased invasiveness and enhanced chemosensitivity. MNZ diminished the invasiveness by inducing mesenchymal-epithelial transition and enhancing chemosensitivity by increasing ENT1 (equilibrative nucleoside transporter 1) and reducing RRM1 (ribonucleotide reductase M1). MNZ reduced cancer stemness in GEM-resistant CCA cells. Combined GEM and MNZ would be a promising therapeutic strategy for cancer stem-like CAA. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
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A surface transporter family conveys the trypanosome differentiation signal.
Dean, Samuel; Marchetti, Rosa; Kirk, Kiaran; Matthews, Keith R
2009-05-14
Microbial pathogens use environmental cues to trigger the developmental events needed to infect mammalian hosts or transmit to disease vectors. The parasites causing African sleeping sickness respond to citrate or cis-aconitate (CCA) to initiate life-cycle development when transmitted to their tsetse fly vector. This requires hypersensitization of the parasites to CCA by exposure to low temperature, conditions encountered after tsetse fly feeding at dusk or dawn. Here we identify a carboxylate-transporter family, PAD (proteins associated with differentiation), required for perception of this differentiation signal. Consistent with predictions for the response of trypanosomes to CCA, PAD proteins are expressed on the surface of the transmission-competent 'stumpy-form' parasites in the bloodstream, and at least one member is thermoregulated, showing elevated expression and surface access at low temperature. Moreover, RNA-interference-mediated ablation of PAD expression diminishes CCA-induced differentiation and eliminates CCA hypersensitivity under cold-shock conditions. As well as being molecular transducers of the differentiation signal in these parasites, PAD proteins provide the first example of a surface marker able to discriminate the transmission stage of trypanosomes in their mammalian host.
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Synthesis and photoluminescence properties of ZnS nanobowl arrays via colloidal monolayer template
2014-01-01
Two-dimensional Zinc sulfide (ZnS) nanobowl arrays were synthesized via self-assembled monolayer polystyrene sphere template floating on precursor solution surface. A facile approach was proposed to investigate the morphology evolution of nanobowl arrays by post-annealing procedure. Photoluminescence (PL) measurement of as-grown nanoarrays shows that the spectrum mainly includes two parts: a purple emission peak at 382 nm and a broad blue emission band centering at 410 nm with a shoulder around 459 nm, and a blue emission band at 440 nm was obtained after the annealing procedure. ZnS nanoarrays with special morphologies and PL emission are benefits to their promising application in novel photoluminescence nanodevice. PMID:25246857
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Medda, Massimo; Lioupis, Christos, E-mail: lioupisC@vodafone.net.gr; Mollichelli, Nadia
2008-03-15
We report the case of a patient with subtotal occlusion of the origin of the left common carotid artery (CCA) following thoracic graft placement. Retrograde endovascular placement of a stent-graft by minimal cervical access was undertaken to repair the occlusive lesion of the left CCA and prevent future complications of endoluminal thoracic reconstruction. The retrograde endovascular repair of CCA lesions, as other authors have already suggested, may be the treatment of choice in 'high-surgical-risk' patients. In these cases where the ostium of supra-aortic trunks is compromised following thoracic aorta stent-graft migration, endoluminal placement of a stent-graft in the CCA canmore » guarantee both maintenance of carotid flow and thoracic stent-graft fixation.« less
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NASA Technical Reports Server (NTRS)
2005-01-01
Three sources have been considered to provide information allowing the evaluation of the Collision Conflict Avoidance (CCA) functional requirements: existing data, simulation, and flight test. The existing data sources that have been evaluated have been found to be lacking in two areas: The actual data that was recorded and missing elements to the system architecture. Many previous tests addressing collision avoidance were conducted without a remote operator. As such, they are missing critical elements that are required to assess the CCA functional requirements. Tests such as ERAST were conducted with all of the UAS elements. However, ERAST tests were conducted as a demonstration and the data recorded was of end-to-end performance. Many contributing elements of the system were not individually recorded or were recorded at a data rate insufficient for the purposes of evaluating the CCA functional requirements.
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Choudhry, Farooq A; Grantham, John T; Rai, Ansaar T; Hogg, Jeffery P
2016-05-01
Stable access is essential for successful intracranial interventions. Quantifying variations in extracranial carotid arteries may help in the selection and development of access catheters. This study describes the vascular dimensions from the aortic arch to the skull base. CT angiography analysis was performed on 100 patients. The lengths, diameters, and tortuosity of the common carotid artery (CCA) and internal carotid artery (ICA) were measured from the aortic arch to the skull base. The mean±SD length of the carotid artery from the aortic arch to the skull base was 22.2±2.2 cm for the right side and 20.8±1.9 cm for the left side (p<0.0001). The length of the right CCA was 13.6±1.2 cm and the length of the left CCA was 12.4±1.4 cm (p<0.0001). The length of the right ICA was 8.6±1.4 cm compared with 8.4±1.4 cm for the left ICA (p=0.3). The ICA length in men and women was 8.9±1.3 cm and 8.2±1.3 cm, respectively (p=0.0001), and the CCA length in men and women was 13.6±1.5 cm and 12.3±1.6 cm, respectively (p<0.0001). The lengths of the CCA and ICA in patients aged ≥60 years were 13.3±1.7 cm and 8.9±1.5 cm, respectively compared with 12.8±1.7 cm and 8.2±1.1 cm, respectively, for patients aged <60 years (p=0.04 for CCA, p=0.0002 for ICA). Tortuosity of the CCA and ICA was 1.2±0.2 and 1.3±0.1, respectively, in patients aged ≥60 years compared with 1.1±0.1 for both the ICA and CCA in patients aged <60 years (p<0.0001 for both). There was a consistent ratio of CCA/ICA length of 1.6±0.3 on the right and 1.5±0.3 on the left (p<0.0001). The arterial diameters did not show any significant difference. The distance from the aortic arch to the skull base is longer on the right than on the left side. Both the CCA and ICA are longer in men and in patients aged ≥60 years. The tortuosity of both segments significantly increases with age. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
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Islam, Rakibul M.; Bell, Robin J.; Billah, Baki; Hossain, Mohammad B.
2015-01-01
Background. Cervical cancer (CCa) is the second most common cancer among women in Bangladesh. The uptake of CCa screening was less than 10% in areas where screening has been offered, so we investigated the awareness of CCa and CCa screening, and factors associated with women’s preparedness to be screened. Methods. A nationally representative, cross-sectional survey of women aged 30–59 years was conducted in 7 districts of the 7 divisions in Bangladesh, using a multistage cluster sampling technique. Factors associated with the awareness of CCa and screening uptake were investigated separately, using multivariable logistic regression. Results. On systematic questioning, 81.3% and 48.6% of the 1,590 participants, whose mean age was 42.3 (±8.0) years, had ever heard of CCa and CCa screening, respectively. Having heard of CCa was associated with living in a rural area (adjusted odds ratio [OR]: 0.42; 95% confidence interval [CI]: 0.26–0.67), being 40–49 years old (OR: 1.59; 95% CI: 1.15–2.0), having no education (OR: 0.25; 95% CI: 0.16–0.38), and being obese (OR: 2.04; 95% CI: 1.23–3.36). Of the 773 women who had ever heard of CCa screening, 86% reported that they had not been screened because they had no symptoms and 37% did not know screening was needed. Only 8.3% had ever been screened. Having been screened was associated with being 40–49 years old (OR: 2.17; 95% CI: 1.19–3.94) and employed outside the home (OR: 3.83; 95% CI: 1.65–8.9), and inversely associated with rural dwelling (OR: 0.54; 95% CI: 0.30–0.98) and having no education (OR: 0.29; 95% CI: 0.10–0.85). Conclusion. Lack of awareness of CCa and of understanding of the concept of screening are the key barriers to screening uptake in women at midlife in Bangladesh. Targeted educational health programs are needed to increase screening in Bangladesh with the view to reducing mortality. Implications for Practice: This is the first nationwide and population-based study in Bangladesh to collect detailed information pertaining to the awareness of cervical cancer and cervical cancer screening, and factors associated with women’s preparedness to undergo screening. Rather than cultural and religious barriers, lack of awareness and knowledge of cervical cancer and screening present the primary barriers to screening uptake. The results highlight the urgent need for health education programs that have the potential to increase cervical cancer awareness and screening uptake, and reduce cervical cancer mortality. PMID:26590177
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Bezerra, Fernando Schemelzer Moraes; Leal, Joames Kauffimann Freitas; Sousa, Mariana Silva; Pinheiro, Marta Cristhiany Cunha; Ramos, Alberto Novaes; Silva-Moraes, Vanessa; Katz, Naftale
2018-06-01
Schistosomiasis is still a public health problem in Brazil. The Kato-Katz test is the most frequently used diagnostic method for Schistosoma mansoni infection. However, it lacks sensitivity in areas of low prevalence. We have assessed the positivity rate of S. mansoni infection in Bananeiras, a village on Capistrano, Ceara, Brazil by performing a point-of-care test in urine to determine the circulating cathodic antigens (POC-CCA), and we compared the findings with those of the Kato-Katz technique for egg detection in stool and an enzyme-linked immunosorbent assay for specific antibodies against adult worms (SWAP-ELISA) in serum before treatment (baseline). Additionally, the POC-CCA and Kato-Katz test results were compared at one and two years post-treatment, and only POC-CCA strips were utilised for follow-up testing on urine samples at 3-6 weeks. Only one sample of stool and urine was collected per event. Overall, 258 individuals were investigated at the baseline. The POC-CCA test detected 10 (3.9%) positive cases; however, this amount increased to 30 (11.6%) when considering trace readings as positive (t + ), whereas the Kato-Katz method found only 4 (1.6%) positive cases and the SWAP-ELISA detected 105 (40.7%) positive cases. The consistency observed between a single POC-CCA (t + ) or (t-) and the Kato-Katz (three slides) was poor (Kappa indexes <0.20). The highest positivity rate as determined by CCA and Kato-Katz was found in adults. At the baseline, a praziquantel treatment was administered to all individuals regardless of their infection status. According to the POC-CCA test, 93% of the previous positive cases became negative by the third week after the treatment; this rate reached 100% at the sixth week assessment. The follow-up showed that of the 175 individuals evaluated at one year post-treatment, only one (0.6%) showed 'trace' results, and all the individuals were negative for eggs in the stool. At two years, all 185 examined individuals were negative by the Kato-Katz method, and 11 (5.9%) presented traces by POC-CCA. Our results indicate that a single POC-CCA test reveals a significantly higher number of positive cases than the Kato-Katz technique for diagnosing S. mansoni in a low endemic setting, when trace results are considered as positive cases. Nevertheless, the true significance of the trace is not clear. These findings reinforce the need to associate different tools for improved schistosomiasis diagnosis in individuals with low parasite burdens. Copyright © 2018. Published by Elsevier B.V.
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Chromated copper arsenate (CCA) is a wood preservative pesticide containing chromium, copper, and arsenic that protects wood against termites, fungi, mites and other pests that can degrade or threaten the integrity of wood products.
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Cooperative Conflict Avoidance Sensor Trade Study Report, Version 2
NASA Technical Reports Server (NTRS)
2004-01-01
This study develops evaluation criteria for systems and technologies against the Cooperative Conflict Avoidance (CCA) requirements for unmanned flight at and above FL430 as part of Step 1 of the Access-5 program. These evaluation criteria are then applied to both current and future technologies to identify those which might be used to provide an Equivalent Level of Safety (ELOS) for CCA. This document provides the results of this analysis of various systems and technologies intended for evaluation as part of the CCA work package.
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Tang, Ya; Gao, Wei; Wang, Xiuli; Ding, Shiming; An, Taicheng; Xiao, Weiyang; Wong, Ming H; Zhang, Chaosheng
2015-01-01
Wood preservatives can protect wood from dry rot, fungi, mould and insect damage, and chromated copper arsenate (CCA) has been used as an inorganic preservative for many years. However, wood treated with CCA has been restricted from residential uses in the EU from June 30, 2004, due to its potential toxicity. Such a regulation is not in place in China yet, and CCA-treated wood is widely used in public parks. A portable XRF analyser was used to investigate arsenic (As) concentration on surfaces of in-service CCA-treated wood planks in a popular park as well as the influencing field factors of age in-service, immersion and human footfall. With a total of 1207 readings, the observed As concentrations varied from below the detection limit (<10 mg/kg) to 15,746 mg/kg with a median of 1160 mg/kg. Strong variation of As concentrations were observed in different wood planks of the same age, on the surface of the same piece of wood, inside the same piece of wood, and different surfaces of walkway planks, hand rails and poles in the field. The oldest planks exhibited high As concentrations, which was related to its original treatment with high retention of CCA preservative. The effect of immersion in the field for about 4 months was insignificant for As concentration on the surfaces. However, a significant reduction of As was observed for immersion combined with human footfall (wiping by shoes). Human traffic in general caused slightly reduced and more evenly distributed As concentrations on the wood surfaces. The strong variation, slow aging and relatively weak immersion effects found in this study demonstrate that the in-service CCA-treated wood poses potential health risks to the park users, due to easy dermal contact especially when the wood is wet after rainfall. It is suggested that further comprehensive investigations and risk assessments of CCA-treated wood in residential areas in China are needed, and precautionary measures should be considered to reduce the potential risks to residents and visitors, especially children.
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Koprowski, Steven; Sokolowski, Kevin; Kunnimalaiyaan, Selvi; Gamblin, T Clark; Kunnimalaiyaan, Muthusamy
2015-10-01
Cholangiocarcinoma (CCA) is highly malignant and characterized by poor prognosis with chemotherapeutic resistance. Therefore, continued development of novel, effective approaches are needed. Notch expression is markedly upregulated in CCA, but the utility of Notch1 inhibition is not defined. Based on recent findings, we hypothesized that curcumin, a polyphenolic phytochemical, suppresses CCA growth in vitro via inhibition of Notch1 signaling. Established CCA cell lines CCLP-1 and SG-231 were treated with varying concentrations of curcumin (0-20 μM). Viability was assessed through 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide and clonogenic assays. Evaluation of apoptosis was determined via Western analysis for apoptotic markers and Caspase-Glo 3/7 assay. Cell lysates were further analyzed via Western blotting for Notch1/HES-1/survivin pathway expression, cell cycle progression, and survival. Curcumin-treated CCA cells exhibited reduced viability compared with control treatment. Statistically significant reductions in cell viability were observed with curcumin treatment at concentrations of 7.5, 10, and 15 μM by approximately 10%, 48%, and 56% for CCLP-1 and 13%, 25%, and 50% for SG-231, respectively. On Western analysis, concentrations of ≥10 μM showed reductions in Notch1, HES-1, and survivin. Apoptosis was evidenced by an increase in expression of cleaved poly [ADP] ribose polymerase and an increase in caspase activity. Cyclin D1 (cell cycle progression) expression levels were also reduced with treatment. Curcumin effectively induces CCA (CCLP-1 and SG-231) growth suppression and apoptosis at relatively low treatment concentrations when compared with the previous research. A concomitant reduction of Notch1, HES-1, and survivin expression in CCA cell lines provides novel evidence for a potential antitumorigenic mechanism-of-action. To our knowledge, this is the first report showing reduction in HES-1 expression via protein analysis after treatment with curcumin. Such findings merit further investigation of curcumin-mediated inhibition of Notch signaling in CCA either alone or in combination with chemotherapeutic agents. Copyright © 2015 Elsevier Inc. All rights reserved.
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Jiang, Xiang; Jin, Ying; Li, Yan; Huang, Hui-Fang; Wu, Ming; Shen, Keng; Pan, Ling-Ya
2014-01-01
The objective of this retrospective study was to analyze the clinical characteristics and prognosis of clear cell adenocarcinoma (CCA) in the post-diethylstilbestrol (DES) era and to evaluate the feasibility of fertility-preserving treatment. The records of 32 patients with CCAs who were treated at Peking Union Medical College Hospital from August 1986 to June 2012 were retrospectively reviewed. Three of the patients had undergone fertility-preserving treatment. The incidence of CCA among cervical adenocarcinomas was 15.2%. The median age was 38 years: 11 patients (34.4%) were diagnosed before 30 years of age and two (6.3%) after 70 years of age. Ten patients (31.2%) were nulliparous. No patient had been exposed to DES. Twenty-nine patients (90.6%) presented with obvious symptoms, and the cervix appeared abnormal in 26 patients (81.3%). Cervical Papanicolaou (Pap) tests were abnormal in all four patients in whom they were performed (three had high-grade squamous intraepithelial lesions and one had atypical squamous cells of undetermined significance). The distribution by stage was 56.3% stage I, 34.4% stage II, 6.3% stage III, and 3.1% stage IV. Treatments mainly included surgery for patients with stage I to IIA CCA and radiochemotherapy for patients with advanced CCA. The overall 5-year progression-free survival was 72.2%. Patients with stage I to IIA CCA had better 5-year progression-free survival than did patients with stage IIB to IV CCA (81.5% versus 40.0%, P=0.003). The three patients who had undergone fertility-preserving treatment had no recurrences. CCA may also affect adolescents and children without prior DES exposure, who are often misdiagnosed as having functional uterine bleeding. Radiotherapy appears to be effective for local control but to have no effect on distant recurrences. In our study, the prognosis of patients with early-stage CCA, including those who had undergone fertility-preserving treatment, was not inferior to that of patients with other types of cervical adenocarcinoma.
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Chang, Tongxin; Du, Binyang; Huang, Haiying; He, Tianbai
2016-08-31
Two kinds of large-area ordered and highly tunable micro/submicro-nanopatterned surfaces in a complementary manner were successfully fabricated by elaborately combining block copolymer self-assembly and colloidal lithography. Employing a monolayer of polystyrene (PS) colloidal spheres assembled on top as etching mask, polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) or polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) micelle films were patterned into micro/submicro patches by plasma etching, which could be further transferred into micropatterned metal nanoarrays by subsequent metal precursor loading and a second plasma etching. On the other hand, micro/submicro-nanopatterns in a complementary manner were generated via preloading a metal precursor in initial micelle films before the assembly of PS colloidal spheres on top. Both kinds of micro/submicro-nanopatterns showed good fidelity at the micro/submicroscale and nanoscale; meanwhile, they could be flexibly tuned by the sample and processing parameters. Significantly, when the PS colloidal sphere size was reduced to 250 nm, a high-resolution submicro-nanostructured surface with 3-5 metal nanoparticles in each patch or a single-nanoparticle interconnected honeycomb network was achieved. Moreover, by applying gold (Au) nanoparticles as anchoring points, micronanopatterned Au arrays can serve as a flexible template to pattern bovine serum albumin (BSA) molecules. This facile and cost-effective approach may provide a novel platform for fabrication of micropatterned nanoarrays with high tunability and controllability, which are promising in the applications of biological and microelectronic fields.
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Glade, Nicolas; Demongeot, Jacques; Tabony, James
2004-01-01
Background The transport of intra-cellular particles by microtubules is a major biological function. Under appropriate in vitro conditions, microtubule preparations behave as a 'complex' system and show 'emergent' phenomena. In particular, they form dissipative structures that self-organise over macroscopic distances by a combination of reaction and diffusion. Results Here, we show that self-organisation also gives rise to a collective transport of colloidal particles along a specific direction. Particles, such as polystyrene beads, chromosomes, nuclei, and vesicles are carried at speeds of several microns per minute. The process also results in the macroscopic self-organisation of these particles. After self-organisation is completed, they show the same pattern of organisation as the microtubules. Numerical simulations of a population of growing and shrinking microtubules, incorporating experimentally realistic reaction dynamics, predict self-organisation. They forecast that during self-organisation, macroscopic parallel arrays of oriented microtubules form which cross the reaction space in successive waves. Such travelling waves are capable of transporting colloidal particles. The fact that in the simulations, the aligned arrays move along the same direction and at the same speed as the particles move, suggest that this process forms the underlying mechanism for the observed transport properties. Conclusions This process constitutes a novel physical chemical mechanism by which chemical energy is converted into collective transport of colloidal particles along a given direction. Self-organisation of this type provides a new mechanism by which intra cellular particles such as chromosomes and vesicles can be displaced and simultaneously organised by microtubules. It is plausible that processes of this type occur in vivo. PMID:15176973
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Tunable plasmon resonances in anisotropic metal nanostructures
NASA Astrophysics Data System (ADS)
Penninkhof, J. J.
2006-09-01
Coherent oscillations of free electrons in a metal, localized in a small volume or at an interface between a metal and a dielectric medium, have attracted a lot of attention in the past decades. These so-called surface plasmons have special optical properties that can be used in many applications ranging from optoelectronics to sensing of small quantities of molecules. One of the key issues is that electromagnetic energy can be confined to a relatively small volume close to the metal surface. This field enhancement and the resonance frequency strongly depend on the shape and size of the metal structures. In this thesis, several fabrication methods to create these metal structures on the nanometer to micrometer scale are presented. The optical properties are studied with a special emphasis on the effect of shape anisotropy. Self-assembled 2D colloidal crystals are used as mask to fabricate arrays of metal triangles on a substrate. One of the limitations of this nanosphere lithography technique is that the size of the holes in the colloidal mask (through which the metal is evaporated) is determined by the size of the colloids in the mask. The masks, however, can be modified by use of MeV ion beams and/or wet-chemical growth of a thin layer of silica, resulting in a reduced hole size. Arbitrary symmetry and spacing can be obtained by use of optical tweezers and angle-resolved metal deposition. In contrast to pure metals, amorphous materials like silica are known to show anisotropic plastic deformation at constant volume when subject to MeV ion irradiation. Gold cores embedded in a silica matrix, however, show an elongation along the direction of the ion beam, whereas silver cores rather disintegrate. Silver nanocrystals in an ion-exchanged soda-lime glass redistribute themselves in arrays along the ion beam direction. The optical extinction becomes polarization-dependent, with red- and blue-shifts of the plasmon resonances for polarizations longitudinal and transverse to the arrays, respectively. The band splitting is attributed to near-field electromagnetic plasmon coupling within the arrays. Finite difference time domain simulations indicate that the combination of particle center-to-center spacing and diameter, rather than inter-particle spacing alone, is the key parameter determining the coupling strength. The resonant electric field is concentrated in the very small gaps between the particles in the array. With the MeV ion beam technique, it is possible to fabricate large substrates with relatively monodisperse oblate ellipsoidal silica-core/metal-shell colloids, with the short axis aligned in the direction of the ion beam. The optical extinction of these particles, is a complex function of the core radius and the shell thickness, due to a competition between phase retardation effects and the coupling between the surface plasmons at the inner and outer surfaces of the shell. After deformation, the extinction is angle- and polarization-dependent. Calculations indicate that large Au-shell particles can sustain cavity modes, for which the electric field is enhanced in almost the full volume of the dielectric core. The resonance frequency is sensitive to the size, shape and dielectric constant of the core, and the polarization direction.
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Patterned assembly of colloidal particles by confined dewetting lithography.
Celio, Hugo; Barton, Emily; Stevenson, Keith J
2006-12-19
We report the assembly of colloidal particles into confined arrangements and patterns on various cleaned and chemically modified solid substrates using a method which we term "confined dewetting lithography" or CDL for short. The experimental setup for CDL is a simple deposition cell where an aqueous suspension of colloidal particles (e.g., polystyrene spheres) is placed between a floating deposition template (i.e., metal microgrid) and the solid substrate. The voids of the deposition template serve as an array of micrometer-sized reservoirs where several hydrodynamic processes are confined. These processes include water evaporation, meniscus formation, convective flow, rupturing, dewetting, and capillary-bridge formation. We discuss the optimal conditions where the CDL has a high efficiency to deposit intricate patterns of colloidal particles using polystyrene spheres (PS; 4.5, 2.0, 1.7, 0.11, 0.064 microm diameter) and square and hexagonal deposition templates as model systems. We find that the optimization conditions of the CDL method, when using submicrometer, sulfate-functionalized PS particles, are primarily dependent on minimizing attractive particle-substrate interactions. The CDL methodology described herein presents a relatively simple and rapid method to assemble virtually any geometric pattern, including more complex patterns assembled using PS particles with different diameters, from aqueous suspensions by choosing suitable conditions and materials.
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Multiset canonical correlations analysis and multispectral, truly multitemporal remote sensing data.
Nielsen, Allan Aasbjerg
2002-01-01
This paper describes two- and multiset canonical correlations analysis (CCA) for data fusion, multisource, multiset, or multitemporal exploratory data analysis. These techniques transform multivariate multiset data into new orthogonal variables called canonical variates (CVs) which, when applied in remote sensing, exhibit ever-decreasing similarity (as expressed by correlation measures) over sets consisting of 1) spectral variables at fixed points in time (R-mode analysis), or 2) temporal variables with fixed wavelengths (T-mode analysis). The CVs are invariant to linear and affine transformations of the original variables within sets which means, for example, that the R-mode CVs are insensitive to changes over time in offset and gain in a measuring device. In a case study, CVs are calculated from Landsat Thematic Mapper (TM) data with six spectral bands over six consecutive years. Both Rand T-mode CVs clearly exhibit the desired characteristic: they show maximum similarity for the low-order canonical variates and minimum similarity for the high-order canonical variates. These characteristics are seen both visually and in objective measures. The results from the multiset CCA R- and T-mode analyses are very different. This difference is ascribed to the noise structure in the data. The CCA methods are related to partial least squares (PLS) methods. This paper very briefly describes multiset CCA-based multiset PLS. Also, the CCA methods can be applied as multivariate extensions to empirical orthogonal functions (EOF) techniques. Multiset CCA is well-suited for inclusion in geographical information systems (GIS).
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Zhao, Xiaofang; Luo, Guosong; Cheng, Ying; Yu, Wenjing; Chen, Run; Xiao, Bin; Xiang, Yuancai; Feng, Chunhong; Fu, Wenguang; Duan, Chunyan; Yao, Fuli; Xia, Xianming; Tao, Qinghua; Wei, Mei; Dai, Rongyang
2018-07-01
Compound C, a well-known inhibitor of AMP-activated protein kinase (AMPK), has been reported to exert antitumor activities in some types of cells. Whether compound C can exert antitumor effects in human cholangiocarcinoma (CCA) remains unknown. Here, we demonstrated that compound C is a potent inducer of cell death and autophagy in human CCA cells. Autophagy inhibitors increased the cytotoxicity of compound C towards human CCA cells, as confirmed by increased LDH release, and PARP cleavage. It is notable that compound C treatment increased phosphorylated Akt, sustained high levels of phosphorylated p70S6K, and decreased mTOR regulated p-ULK1 (ser757). Based on the data that blocking PI3K/Akt or mTOR had no apparent influence on autophagic response, we suggest that compound C induces autophagy independent of Akt/mTOR signaling in human CCA cells. Further study demonstrated that compound C inhibited the phosphorylation of JNK and its target c-Jun. Blocking JNK by SP600125 or siRNA suppressed autophagy induction upon compound C treatment. Moreover, compound C induced p38 MAPK activation, and its inhibition promoted autophagy induction via JNK activation. In addition, compound C induced p53 expression, and its inhibition attenuated compound C-induced autophagic response. Thus, compound C triggers autophagy, at least in part, via the JNK and p53 pathways in human CCA cells. In conclusion, suppresses autophagy could increase compound C sensitivity in human CCA. © 2018 Wiley Periodicals, Inc.
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NASA Technical Reports Server (NTRS)
Sathyanarayanan, P. V.; Cremo, C. R.; Poovaiah, B. W.
2000-01-01
Chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK) is characterized by a serine-threonine kinase domain, an autoinhibitory domain, a calmodulin-binding domain and a neural visinin-like domain with three EF-hands. The neural visinin-like Ca(2+)-binding domain at the C-terminal end of the CaM-binding domain makes CCaMK unique among all the known calmodulin-dependent kinases. Biological functions of the plant visinin-like proteins or visinin-like domains in plant proteins are not well known. Using EF-hand deletions in the visinin-like domain, we found that the visinin-like domain regulated Ca(2+)-stimulated autophosphorylation of CCaMK. To investigate the effects of Ca(2+)-stimulated autophosphorylation on the interaction with calmodulin, the equilibrium binding constants of CCaMK were measured by fluorescence emission anisotropy using dansylated calmodulin. Binding was 8-fold tighter after Ca(2+)-stimulated autophosphorylation. This shift in affinity did not occur in CCaMK deletion mutants lacking Ca(2+)-stimulated autophosphorylation. A variable calmodulin affinity regulated by Ca(2+)-stimulated autophosphorylation mediated through the visinin-like domain is a new regulatory mechanism for CCaMK activation and calmodulin-dependent protein kinases. Our experiments demonstrate the existence of two functional molecular switches in a protein kinase regulating the kinase activity, namely a visinin-like domain acting as a Ca(2+)-triggered switch and a CaM-binding domain acting as an autophosphorylation-triggered molecular switch.
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Wettability and friction coefficient of micro-magnet arrayed surface
NASA Astrophysics Data System (ADS)
Huang, Wei; Liao, Sijie; Wang, Xiaolei
2012-01-01
Surface coating is an important part of surface engineering and it has been successfully used in many applications to improve the performance of surfaces. In this paper, magnetic arrayed films with different thicknesses were fabricated on the surface of 316 stainless steel disks. Controllable colloid - ferrofluids (FF) was chosen as lubricant, which can be adsorbed on the magnetic surface. The wettability of the micro-magnet arrayed surface was evaluated by measuring the contract angle of FF drops on surface. Tribological experiments were carried out to investigate the effects of magnetic film thickness on frictional properties when lubricated by FF under plane contact condition. It was found that the magnetic arrayed surface with thicker magnetic films presented larger contract angle. The frictional test results showed that samples with thicker magnetic films could reduce friction and wear more efficiently at higher sliding velocity under the lubrication of FF.
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Kühler, Paul; Weber, Max; Lohmüller, Theobald
2014-06-25
We demonstrate a strategy for surface-enhanced Raman spectroscopy (SERS) of supported lipid membranes with arrays of plasmonic nanoantennas. Colloidal lithography refined with plasma etching is used to synthesize arrays of triangular shaped gold nanoparticles. Reducing the separation distance between the triangle tips leads to plasmonic coupling and to a strong enhancement of the electromagnetic field in the nanotriangle gap. As a result, the Raman scattering intensity of molecules that are located at this plasmonic "hot-spot" can be increased by several orders of magnitude. The nanoantenna array is then embedded with a supported phospholipid membrane which is fluid at room temperature and spans the antenna gap. This configuration offers the advantage that molecules that are mobile within the bilayer membrane can enter the "hot-spot" region via diffusion and can therefore be measured by SERS without static entrapment or adsorption of the molecules to the antenna itself.
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Physics of Hard Spheres Experiment (PhaSE) or "Making Jello in Space"
NASA Technical Reports Server (NTRS)
Ling, Jerri S.; Doherty, Michael P.
1998-01-01
The Physics of Hard Spheres Experiment (PHaSE) is a highly successful experiment that flew aboard two shuttle missions to study the transitions involved in the formation of jellolike colloidal crystals in a microgravity environment. A colloidal suspension, or colloid, consists of fine particles, often having complex interactions, suspended in a liquid. Paint, ink, and milk are examples of colloids found in everyday life. In low Earth orbit, the effective force of gravity is thousands of times less than at the Earth's surface. This provides researchers a way to conduct experiments that cannot be adequately performed in an Earth-gravity environment. In microgravity, colloidal particles freely interact without the complications of settling that occur in normal gravity on Earth. If the particle interactions within these colloidal suspensions could be predicted and accurately modeled, they could provide the key to understanding fundamental problems in condensed matter physics and could help make possible the development of wonderful new "designer" materials. Industries that make semiconductors, electro-optics, ceramics, and composites are just a few that may benefit from this knowledge. Atomic interactions determine the physical properties (e.g., weight, color, and hardness) of ordinary matter. PHaSE uses colloidal suspensions of microscopic solid plastic spheres to model the behavior of atomic interactions. When uniformly sized hard spheres suspended in a fluid reach a certain concentration (volume fraction), the particle-fluid mixture changes from a disordered fluid state, in which the spheres are randomly organized, to an ordered "crystalline" state, in which they are structured periodically. The thermal energy of the spheres causes them to form ordered arrays, analogous to crystals. Seven of the eight PHaSE samples ranged in volume fraction from 0.483 to 0.624 to cover the range of interest, while one sample, having a concentration of 0.019, was included for instrument calibration.
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Komanicky, Vladimir; Barbour, Andi; Lackova, Miroslava; ...
2014-07-05
Here, we developed a method for production of arrays of platinum nanocrystals of controlled size and shape using templates from ordered silica bead monolayers. Silica beads with nominal sizes of 150 and 450 nm were self-assembl into monolayers over strontium titanate single crystal substrates. The monolayers were used as shadow masks for platinum metal deposition on the substrate using the three-step evaporation technique. Produced arrays of epitaxial platinum islands were transformed into nanocrystals by annealing in a quartz tube in nitrogen flow. The shape of particles is determined by the substrate crystallography, while the size of the particles and theirmore » spacing are controlled by the size of the silica beads in the mono- layer mask. As a proof of concept, arrays of platinum nanocrystals of cubooctahedral shape were prepared on (100) strontium titanate substrates. We also characterized the nanocrystal arrays by atomic force microscopy, scanning electron microscopy, and synchrotron X-ray diffraction techniques.« less
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Hyperinsulin therapy for calcium channel antagonist poisoning: a seven-year retrospective study.
Espinoza, Tamara R; Bryant, Sean M; Aks, Steve E
2013-01-01
The use of hyperinsulin therapy (HIT) in severe calcium channel antagonist (CCA) poisoning has become a more common therapy within the last decade. The objective of this study is to report 7 years of experience recommending HIT. This was a retrospective chart review utilizing our regional poison center (RPC) data from January 1, 2002, through December 31, 2008. All cases of CCA poisoning receiving HIT were searched. Endpoints included the number of CCA cases utilizing HIT, insulin dose, time of initiation of HIT, patient outcome, adverse events, age, glucose concentration, and lowest systolic blood pressure recorded. Forty-six cases of CCA poisoning were managed with HIT over 7 years. All the patients received standard antidotal therapy (= intravenous fluids, calcium salts, glucagon, and pressors). HIT administration followed our RPC recommendation 23 times (50%), and no hypoglycemic events occurred. Means (age, highest glucose measured, and lowest systolic blood pressure measured) were 51 years, 282 mg/dL, and 74 mm Hg, respectively. Our RPC recommendations for HIT were followed 50% of the time over the last 7 years. In light of the lack of hypoglycemia associated with HIT in our study population, we recommend HIT as an early and safe antidote in significant CCA poisoning.
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Li, Huihui; Zhu, Houjuan; Sun, Mingtai; Yan, Yehan; Zhang, Kui; Huang, Dejian; Wang, Suhua
2015-08-11
Herein, we report a novel approach to the rapid visual detection of gaseous sulfur dioxide (SO2) by manipulating the surface chemistry of 3-aminopropyltriethoxysilane (APTS)-modified quantum dots (QDs) using fluorescent coumarin-3-carboxylic acid (CCA) for specific reaction with SO2. The CCA molecules are attached to the surface amino groups of the QDs through electrostatic attraction, thus the fluorescence of CCA is greatly suppressed because of the formation of an ion-pair complex between the ATPS-modified QDs and CCA. Such an interaction is vulnerable to SO2 because SO2 can readily react with surface amino groups to form strong charge-transfer complexes and subsequently release the strongly fluorescent CCA molecules. The mechanism has been carefully verified through a series of control experiments. Upon exposure to different amounts of SO2, the fluorescent color of the nanoparticle-based sensor displays continuously changes from red to blue. Most importantly, the approach owns high selectivity for SO2 and a tolerance of interference, which enables the sensor to detect SO2 in a practical application. Using this fluorescence-based sensing method, we have achieved a visual detection limit of 6 ppb for gaseous SO2.
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Whitehouse, Andrew J O; Coon, Hilary; Miller, Judith; Salisbury, Bryanna; Bishop, Dorothy V M
2010-11-01
This study investigated whether the Communication Checklist - Adult (CC-A) could identify subtypes of social and communication dysfunction in autism probands and their parents. The CC-A is divided into subscales measuring linguistic ability as well as two aspects of social communication: the Pragmatic Skills subscale assesses the level of pragmatic oddities (e.g. excessive talking), while the Social Engagement subscale picks up on those behaviours that reflect a more passive communication style (e.g. failure to engage in social interactions). CC-A data were collected for 69 autism probands, 238 parents of autism probands and 187 typical participants. The CC-A proved sensitive to the communication difficulties of autism probands and a proportion of their parents. The majority of parents who demonstrated the broader phenotype scored poorly on either the Pragmatic Skills or Social Engagement scale only. The Social Engagement scale was particularly sensitive to the difficulties of the parents, indicating that social-communicative passivity may be an important part of the broader autism phenotype. The findings provide evidence for the existence of more constrained pragmatic phenotypes in autism. Molecular genetic studies in this area may benefit from stratifying samples according to these phenotypes.
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Boat noise prevents soundscape-based habitat selection by coral planulae.
Lecchini, David; Bertucci, Frédéric; Gache, Camille; Khalife, Adam; Besson, Marc; Roux, Natacha; Berthe, Cecile; Singh, Shubha; Parmentier, Eric; Nugues, Maggy M; Brooker, Rohan M; Dixson, Danielle L; Hédouin, Laetitia
2018-06-18
Understanding the relationship between coral reef condition and recruitment potential is vital for the development of effective management strategies that maintain coral cover and biodiversity. Coral larvae (planulae) have been shown to use certain sensory cues to orient towards settlement habitats (e.g. the odour of live crustose coralline algae - CCA). However, the influence of auditory cues on coral recruitment, and any effect of anthropogenic noise on this process, remain largely unknown. Here, we determined the effect of protected reef (MPA), exploited reef (non-MPA) soundscapes, and a source of anthropogenic noise (boat) on the habitat preference for live CCA over dead CCA in the planula of two common Indo-Pacific coral species (Pocillopora damicornis and Acropora cytherea). Soundscapes from protected reefs significantly increased the phonotaxis of planulae of both species towards live CCA, especially when compared to boat noise. Boat noise playback prevented this preferential selection of live CCA as a settlement substrate. These results suggest that sources of anthropogenic noise such as motor boat can disrupt the settlement behaviours of coral planulae. Acoustic cues should be accounted for when developing management strategies aimed at maximizing larval recruitment to coral reefs.
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Ethanol-assisted multi-sensitive poly(vinyl alcohol) photonic crystal sensor.
Chen, Cheng; Zhu, Yihua; Bao, Hua; Shen, Jianhua; Jiang, Hongliang; Peng, Liming; Yang, Xiaoling; Li, Chunzhong; Chen, Guorong
2011-05-21
An ethanol-assisted method is utilized to generate a robust gelated crystalline colloidal array (GCCA) photonic crystal sensor. The functionalized sensor efficiently diffracts the visible light and responds to various stimuli involving solvent, pH, cation, and compressive strain; the related color change can be easily distinguished by the naked eye. © The Royal Society of Chemistry 2011
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A CMOS Time-Resolved Fluorescence Lifetime Analysis Micro-System
Rae, Bruce R.; Muir, Keith R.; Gong, Zheng; McKendry, Jonathan; Girkin, John M.; Gu, Erdan; Renshaw, David; Dawson, Martin D.; Henderson, Robert K.
2009-01-01
We describe a CMOS-based micro-system for time-resolved fluorescence lifetime analysis. It comprises a 16 × 4 array of single-photon avalanche diodes (SPADs) fabricated in 0.35 μm high-voltage CMOS technology with in-pixel time-gated photon counting circuitry and a second device incorporating an 8 × 8 AlInGaN blue micro-pixellated light-emitting diode (micro-LED) array bump-bonded to an equivalent array of LED drivers realized in a standard low-voltage 0.35 μm CMOS technology, capable of producing excitation pulses with a width of 777 ps (FWHM). This system replaces instrumentation based on lasers, photomultiplier tubes, bulk optics and discrete electronics with a PC-based micro-system. Demonstrator lifetime measurements of colloidal quantum dot and Rhodamine samples are presented. PMID:22291564
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PD-L1 expression in extrahepatic cholangiocarcinoma.
Walter, Dirk; Herrmann, Eva; Schnitzbauer, Andreas A; Zeuzem, Stefan; Hansmann, Martin Leo; Peveling-Oberhag, Jan; Hartmann, Sylvia
2017-09-01
To investigate the expression of the programmed cell death 1 (PD-1) receptor-programmed cell death ligand 1 (PD-L1) pathway and the clinicopathological characteristics in extrahepatic cholangiocarcinoma (eCCA). Tissue samples from patients with eCCA [n = 69; perihilar cholangiocarcinoma (CCA), 40; and distal CCA, 29] who underwent surgical resection in the period from 2007 to 2015 were evaluated for PD-1, PD-L1, CD3 and CD163 expression, and correlations with clinicopathological characteristics, including survival data, were determined. PD-L1 was found on both tumour cells of eCCA (8/69, 11.6%) and tumour-associated macrophages (21/69, 30.4%). Significant correlations of PD-L1 expression on cancer cells with venous invasion (P = 0.031) and poor differentiation of the tumour (P = 0.048) were observed. In 19 of 69 (27.5%) samples, tumour-infiltrating lymphocytes (TILs) expressed PD-1, whereas infiltration with CD3-positive and CD163-positive cells was found in 63 of 69 (91.3%) and 68 of 69 (98.6%) cases, respectively. The presence of fewer than five CD3-positive cells per high-power field was significantly correlated with poorer differentiation (P = 0.015) and venous invasion (P < 0.001) of CCA. PD-L1 expression was not correlated with patient survival, but PD-L1 expression on tumour cells combined with low infiltration of CD3-positive TILs was associated with an unfavourable outcome (P = 0.027). Only a small number of eCCA patients are PD-L1-positive, which might be important for future application of PD-1/PD-L1-targeted immune-modulating therapy in these patients. A small subgroup of eCCAs with PD-L1 expression and low lymphocytic infiltration showed more invasive growth and worse overall survival. © 2017 John Wiley & Sons Ltd.
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Nambi, Vijay; Chambless, Lloyd; He, Max; Folsom, Aaron R; Mosley, Tom; Boerwinkle, Eric; Ballantyne, Christie M
2012-01-01
Carotid intima-media thickness (CIMT) and plaque information can improve coronary heart disease (CHD) risk prediction when added to traditional risk factors (TRF). However, obtaining adequate images of all carotid artery segments (A-CIMT) may be difficult. Of A-CIMT, the common carotid artery intima-media thickness (CCA-IMT) is relatively more reliable and easier to measure. We evaluated whether CCA-IMT is comparable to A-CIMT when added to TRF and plaque information in improving CHD risk prediction in the Atherosclerosis Risk in Communities (ARIC) study. Ten-year CHD risk prediction models using TRF alone, TRF + A-CIMT + plaque, and TRF + CCA-IMT + plaque were developed for the overall cohort, men, and women. The area under the receiver operator characteristic curve (AUC), per cent individuals reclassified, net reclassification index (NRI), and model calibration by the Grønnesby-Borgan test were estimated. There were 1722 incident CHD events in 12 576 individuals over a mean follow-up of 15.2 years. The AUC for TRF only, TRF + A-CIMT + plaque, and TRF + CCA-IMT + plaque models were 0.741, 0.754, and 0.753, respectively. Although there was some discordance when the CCA-IMT + plaque- and A-CIMT + plaque-based risk estimation was compared, the NRI and clinical NRI (NRI in the intermediate-risk group) when comparing the CIMT models with TRF-only model, per cent reclassified, and test for model calibration were not significantly different. Coronary heart disease risk prediction can be improved by adding A-CIMT + plaque or CCA-IMT + plaque information to TRF. Therefore, evaluating the carotid artery for plaque presence and measuring CCA-IMT, which is easier and more reliable than measuring A-CIMT, provide a good alternative to measuring A-CIMT for CHD risk prediction.
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2015-01-01
Large area arrays of magnetic, semiconducting, and insulating nanorings were created by coupling colloidal lithography with nanoscale electrodeposition. This versatile nanoscale fabrication process allows for the independent tuning of the spacing, diameter, and width of the nanorings with typical values of 1.0 μm, 750 nm, and 100 nm, respectively, and was used to form nanorings from a host of materials: Ni, Co, bimetallic Ni/Au, CdSe, and polydopamine. These nanoring arrays have potential applications in memory storage, optical materials, and biosensing. A modified version of this nanoscale electrodeposition process was also used to create arrays of split gold nanorings. The size of the split nanoring opening was controlled by the angle of photoresist exposure during the fabrication process and could be varied from 50% down to 10% of the ring circumference. The large area (cm2 scale) gold split nanoring array surfaces exhibited strong polarization-dependent plasmonic absorption bands for wavelengths from 1 to 5 μm. Plasmonic nanoscale split ring arrays are potentially useful as tunable dichroic materials throughout the infrared and near-infrared spectral regions. PMID:25553204
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SYNERGISTIC WOOD PRESERVATIVES FOR REPLACEMENT OF CCA
The objective of this project was to evaluate the potential synergistic combinations of environmentally-safe biocides as wood preservatives. These wood preservatives could be potential replacements for the heavy-metal based CCA.
Didecyldimethylammonium chloride [DDAC] was... -
Using recycled concrete in MDOT's transportation infrastructure : manual of practice.
DOT National Transportation Integrated Search
2011-08-01
"Crushed concrete aggregate (CCA) is granular material manufactured by removing, crushing, and : processing old concrete for reuse as an aggregate source in new construction. Although the Michigan : Department of Transportation (MDOT) has used CCA si...
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Targeted therapy in biliary tract cancers-current limitations and potentials in the future.
Sahu, Selley; Sun, Weijing
2017-04-01
Biliary tract cancers (BTC)/Cholangiocarcinoma (CCA) is an aggressive biliary tract epithelial malignancy from varying locations within the biliary tree with cholangiocyte depreciation., including intrahepatic cholangiocarcinoma (iCCA) (iCCA), extrahepatic cholangiocarcinoma (eCCA) and gallbladder carcinoma (GBC). The disease is largely heterogeneous in etiology, epidemiology, and molecular profile. There are limited treatment options and low survival rates for those patients with advanced or metastatic disease. Systemic treatment is confined to cytotoxic chemotherapy with the combination of gemcitabine and cisplatin. Lack of a stereotype genetic signature makes difficult in identification of potential actionable target directly, which may also explain lack of obvious clinic benefit with target oriented agents from current studies. It is crucial to understand of BTC carcinogenesis, tumor-stroma interactions, and key molecular pathways, and herald to establish targeted, individualized therapies for the heterogeneous disease, and eventually to improve the survival and overall outcome of patients.
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A Canonical Ensemble Correlation Prediction Model for Seasonal Precipitation Anomaly
NASA Technical Reports Server (NTRS)
Shen, Samuel S. P.; Lau, William K. M.; Kim, Kyu-Myong; Li, Guilong
2001-01-01
This report describes an optimal ensemble forecasting model for seasonal precipitation and its error estimation. Each individual forecast is based on the canonical correlation analysis (CCA) in the spectral spaces whose bases are empirical orthogonal functions (EOF). The optimal weights in the ensemble forecasting crucially depend on the mean square error of each individual forecast. An estimate of the mean square error of a CCA prediction is made also using the spectral method. The error is decomposed onto EOFs of the predictand and decreases linearly according to the correlation between the predictor and predictand. This new CCA model includes the following features: (1) the use of area-factor, (2) the estimation of prediction error, and (3) the optimal ensemble of multiple forecasts. The new CCA model is applied to the seasonal forecasting of the United States precipitation field. The predictor is the sea surface temperature.
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Physics of Hard Sphere Experiment: Scattering, Rheology and Microscopy Study of Colloidal Particles
NASA Technical Reports Server (NTRS)
Cheng, Z.-D.; Zhu, J.; Phan, S.-E.; Russel, W. B.; Chaikin, P. M.; Meyer, W. V.
2002-01-01
The Physics of Hard Sphere Experiment has two incarnations: the first as a scattering and rheology experiment on STS-83 and STS-94 and the second as a microscopy experiment to be performed in the future on LMM on the space station. Here we describe some of the quantitative and qualitative results from previous flights on the dynamics of crystallization in microgravity and especially the observed interaction of growing crystallites in the coexistance regime. To clarify rheological measurements we also present ground based experiments on the low shear rate viscosity and diffusion coefficient of several hard sphere experiments at high volume fraction. We also show how these experiments will be performed with confocal microscopy and laser tweezers in our lab and as preparation for the phAse II experiments on LMM. One of the main aims of the microscopy study will be the control of colloidal samples using an array of applied fields with an eye toward colloidal architectures. Temperature gradients, electric field gradients, laser tweezers and a variety of switchable imposed surface patterns are used toward this control.
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Cerebral watershed infarcts may be induced by hemodynamic changes in blood flow.
Shi, Jingfei; Meng, Ran; Konakondla, Sanjay; Ding, Yuchuan; Duan, Yunxia; Wu, Di; Wang, Bincheng; Luo, Yinghao; Ji, Xunming
2017-06-01
A watershed infarct is defined as an ischemic lesion at the border zones between territories of two major arteries. The pathogenesis of watershed infarcts, specifically whether they are caused by hemodynamic or embolic mechanisms, has long been debated. In this study, we aimed to examine whether watershed infarcts can be induced by altering the hemodynamic conditions in rats. In phase one, to determine the proper clamping duration for a reproducible infarct, 30 rats were equally divided into 5 subgroups and underwent bilateral common carotid artery (CCA) clamping for different durations (0.5, 1.0, 1.5, 2.0, and 3.0 hours). In phase two, to analyze the types of infarcts induced by bilateral CCA clamping, 40 rats were subjected to bilateral CCA clamping for 2 hours. As a control, 8 rats underwent all the operation procedures except bilateral CCA clamping. We performed 7.0T magnetic resonance imaging on the surviving rats on the second day to evaluate the extent of the infarcts. We further identified and examined the infarcts with brain slices stained using 2, 3, 5-triphenyltetrazolium chloride (TTC) on the third day. After 2 hours of bilateral CCA clamping, cerebral infarction occurred in 42% of surviving rats (13/31). The majority of the ischemic lesions were located in watershed regions of the brain, demonstrated by both MRI and TTC staining. Watershed infarcts were induced through changing hemodynamic conditions by bilateral CCA clamping in rats. This method may lead to the development of a reliable rodent model for watershed infarcts.
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Chiang, Kun-Chun; Yeh, Ta-Sen; Huang, Cheng-Cheng; Chang, Yu-Chan; Juang, Horng-Heng; Cheng, Chi-Tung; Pang, Jong-Hwei S.; Hsu, Jun-Te; Takano, Masashi; Chen, Tai C.; Kittaka, Atsushi; Hsiao, Michael; Yeh, Chun-Nan
2017-01-01
Cholangiocarcinoma (CCA) is a devastating disease due to no effective treatments available. Since the non-mineral functions of vitamin D emerges, 1α,25(OH)2D3, the active form of vitamin D, has been applied in anti-cancer researches. In this study, we demonstrated that both the 1α,25(OH)2D3 analog, MART-10, and 1α,25(OH)2D3 possessed anti-growth effect on human CCA cells with MART-10 much more potent than 1α,25(OH)2D3. The growth inhibition of both drugs were mediated by induction of G0/G1 cell cycle arrest through upregulation of p27 and downregulation of CDK4, CDK6, and cyclin D3. Human neutrophil gelatinase associated lipocalin (NGAL) was found to be involved in 1α,25(OH)2D3 and MART-10 meditated growth inhibition for CCA as knockdown of NGAL decreased Ki-67 expression in SNU308 cells and rendered SNU308 cells less responsive to 1α,25(OH)2D3 and MART-10 treatment. Vitamin D receptor (VDR) knockdown partly abolished MART-10-induced inhibition of NGAL and cell growth in SNU308 cells. The xenograft animal study demonstrated MART-10 could effectively repressed CCA growth in vivo without inducing obvious side effects. The IHC examination of human CCA specimen for VDR revealed that higher VDR expression was linked with better prognosis. Collectively, our results suggest that MART-10 could be a promising regimen for CCA treatment. PMID:28256614
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Evaluating endothelial function of the common carotid artery: an in vivo human model.
Mazzucco, S; Bifari, F; Trombetta, M; Guidi, G C; Mazzi, M; Anzola, G P; Rizzuto, N; Bonadonna, R
2009-03-01
Flow mediated dilation (FMD) of peripheral conduit arteries is a well-established tool to evaluate endothelial function. The aims of this study are to apply the FMD model to cerebral circulation by using acetazolamide (ACZ)-induced intracranial vasodilation as a stimulus to increase common carotid artery (CCA) diameter in response to a local increase of blood flow velocity (BFV). In 15 healthy subjects, CCA end-diastolic diameter and BFV, middle cerebral artery (MCA) BFV and mean arterial blood pressure (MBP) were measured at basal conditions, after an intravenous bolus of 1g ACZ, and after placebo (saline) sublingual administration at the 15th and 20th minute. In a separate session, the same parameters were evaluated after placebo (saline) infusion instead of ACZ and after 10 microg/m(2) bs and 300 microg of glyceryl trinitrate (GTN), administered sublingually, at the 15th and 20th minute, respectively. After ACZ bolus, there was a 35% maximal MCA mean BFV increment (14th minute), together with a 22% increase of mean CCA end-diastolic BFV and a CCA diameter increment of 3.9% at the 3rd minute (p=0.024). There were no MBP significant variations up to the 15th minute (p=0.35). After GTN administration, there was a significant increment in CCA diameter (p<0.00001). ACZ causes a detectable CCA dilation in healthy individuals concomitantly with an increase in BFV. Upon demonstration that this phenomenon is endothelium dependent, this experimental model might become a valuable tool to assess endothelial function in the carotid artery.
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Levin-Schwartz, Yuri; Song, Yang; Schreier, Peter J.; Calhoun, Vince D.; Adalı, Tülay
2016-01-01
Due to their data-driven nature, multivariate methods such as canonical correlation analysis (CCA) have proven very useful for fusion of multimodal neurological data. However, being able to determine the degree of similarity between datasets and appropriate order selection are crucial to the success of such techniques. The standard methods for calculating the order of multimodal data focus only on sources with the greatest individual energy and ignore relations across datasets. Additionally, these techniques as well as the most widely-used methods for determining the degree of similarity between datasets assume sufficient sample support and are not effective in the sample-poor regime. In this paper, we propose to jointly estimate the degree of similarity between datasets and their order when few samples are present using principal component analysis and canonical correlation analysis (PCA-CCA). By considering these two problems simultaneously, we are able to minimize the assumptions placed on the data and achieve superior performance in the sample-poor regime compared to traditional techniques. We apply PCA-CCA to the pairwise combinations of functional magnetic resonance imaging (fMRI), structural magnetic resonance imaging (sMRI), and electroencephalogram (EEG) data drawn from patients with schizophrenia and healthy controls while performing an auditory oddball task. The PCA-CCA results indicate that the fMRI and sMRI datasets are the most similar, whereas the sMRI and EEG datasets share the least similarity. We also demonstrate that the degree of similarity obtained by PCA-CCA is highly predictive of the degree of significance found for components generated using CCA. PMID:27039696
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Whole-Genome and Epigenomic Landscapes of Etiologically Distinct Subtypes of Cholangiocarcinoma.
Jusakul, Apinya; Cutcutache, Ioana; Yong, Chern Han; Lim, Jing Quan; Huang, Mi Ni; Padmanabhan, Nisha; Nellore, Vishwa; Kongpetch, Sarinya; Ng, Alvin Wei Tian; Ng, Ley Moy; Choo, Su Pin; Myint, Swe Swe; Thanan, Raynoo; Nagarajan, Sanjanaa; Lim, Weng Khong; Ng, Cedric Chuan Young; Boot, Arnoud; Liu, Mo; Ong, Choon Kiat; Rajasegaran, Vikneswari; Lie, Stefanus; Lim, Alvin Soon Tiong; Lim, Tse Hui; Tan, Jing; Loh, Jia Liang; McPherson, John R; Khuntikeo, Narong; Bhudhisawasdi, Vajaraphongsa; Yongvanit, Puangrat; Wongkham, Sopit; Totoki, Yasushi; Nakamura, Hiromi; Arai, Yasuhito; Yamasaki, Satoshi; Chow, Pierce Kah-Hoe; Chung, Alexander Yaw Fui; Ooi, London Lucien Peng Jin; Lim, Kiat Hon; Dima, Simona; Duda, Dan G; Popescu, Irinel; Broet, Philippe; Hsieh, Sen-Yung; Yu, Ming-Chin; Scarpa, Aldo; Lai, Jiaming; Luo, Di-Xian; Carvalho, André Lopes; Vettore, André Luiz; Rhee, Hyungjin; Park, Young Nyun; Alexandrov, Ludmil B; Gordân, Raluca; Rozen, Steven G; Shibata, Tatsuhiro; Pairojkul, Chawalit; Teh, Bin Tean; Tan, Patrick
2017-10-01
Cholangiocarcinoma (CCA) is a hepatobiliary malignancy exhibiting high incidence in countries with endemic liver-fluke infection. We analyzed 489 CCAs from 10 countries, combining whole-genome (71 cases), targeted/exome, copy-number, gene expression, and DNA methylation information. Integrative clustering defined 4 CCA clusters-fluke-positive CCAs (clusters 1/2) are enriched in ERBB2 amplifications and TP53 mutations; conversely, fluke-negative CCAs (clusters 3/4) exhibit high copy-number alterations and PD-1 / PD-L2 expression, or epigenetic mutations ( IDH1/2, BAP1 ) and FGFR / PRKA -related gene rearrangements. Whole-genome analysis highlighted FGFR2 3' untranslated region deletion as a mechanism of FGFR2 upregulation. Integration of noncoding promoter mutations with protein-DNA binding profiles demonstrates pervasive modulation of H3K27me3-associated sites in CCA. Clusters 1 and 4 exhibit distinct DNA hypermethylation patterns targeting either CpG islands or shores-mutation signature and subclonality analysis suggests that these reflect different mutational pathways. Our results exemplify how genetics, epigenetics, and environmental carcinogens can interplay across different geographies to generate distinct molecular subtypes of cancer. Significance: Integrated whole-genome and epigenomic analysis of CCA on an international scale identifies new CCA driver genes, noncoding promoter mutations, and structural variants. CCA molecular landscapes differ radically by etiology, underscoring how distinct cancer subtypes in the same organ may arise through different extrinsic and intrinsic carcinogenic processes. Cancer Discov; 7(10); 1116-35. ©2017 AACR. This article is highlighted in the In This Issue feature, p. 1047 . ©2017 American Association for Cancer Research.
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Yeesoonsang, Seesai; Bilheem, Surichai; McNeil, Edward; Iamsirithaworn, Sophon; Jiraphongsa, Chuleeporn; Sriplung, Hutcha
2017-01-01
Histological specimens are not required for diagnosis of liver and bile duct (LBD) cancer, resulting in a high percentage of unknown histologies. We compared estimates of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) incidences by imputing these unknown histologies. A retrospective study was conducted using data from the Songkhla Cancer Registry, southern Thailand, from 1989 to 2013. Multivariate imputation by chained equations (mice) was used in re-classification of the unknown histologies. Age-standardized rates (ASR) of HCC and CCA by sex were calculated and the trends were compared. Of 2,387 LBD cases, 61% had unknown histology. After imputation, the ASR of HCC in males during 1989 to 2007 increased from 4 to 10 per 100,000 and then decreased after 2007. The ASR of CCA increased from 2 to 5.5 per 100,000, and the ASR of HCC in females decreased from 1.5 in 2009 to 1.3 in 2013 and that of CCA increased from less than 1 to 1.9 per 100,000 by 2013. of complete case analysis showed somewhat similar, although less dramatic, trends. In Songkhla, the incidence of CCA appears to be stable after increasing for 20 years whereas the incidence of HCC is now declining. The decline in incidence of HCC among males since 2007 is probably due to implementation of the hepatitis B virus vaccine in the 1990s. The rise in incidence of CCA is a concern and highlights the need for case control studies to elucidate the risk factors.
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A non-contact approach for PWV detection: application in a clinical setting.
Campo, Adriaan; Heuten, Hilde; Goovaerts, Inge; Ennekens, Guy; Vrints, Christiaan; Dirckx, Joris
2016-07-01
A need for screening methods for arteriosclerosis led to the development of several approaches to measure pulse wave velocity (PWV) being indicative of arterial stiffness. Carotid-femoral PWV (cfPWV) can be measured between common carotid artery (CCA) and femoral artery (FA) displaying the physiologically important stiffness of the conduit arteries. However, this measurement approach has several disadvantages, and a local PWV-measurement of CCA-stiffness has been proposed as an alternative in the past. In the presented pilot study, laser Doppler vibrometry (LDV) is used to measure PWV locally in the CCA (PWVLDV) in 48 patients aged between 48 and 70, with known atherosclerotic arterial disease: stabilized coronary artery disease (CAD), cerebro-vascular disease (CVD) or peripheral artery disease (PAD). Additionally, cfPWV, CCA distensibility coefficient (DC), CCA intima-media thickness (IMT), blood pressure (BP) and age were evaluated. LDV is a valid method for local PWV-measurement. The method is potentially easy to use, and causes no discomfort to the patient. PWVLDV correlates with age (R = 0.432; p = 0.002) as reported in related studies using other techniques, and measured values lay between 2.5 and 5.8 m s(-1), which is well in line with literature measures of local PWV in the CCA. In conclusion, PWVLDV potentially is a marker for arterial health, but more research in a larger and more homogeneous patient population is mandatory. In future studies, blood velocity measurements should be incorporated, as well as a reference method such as pulse wave imaging (PWI) or magnetic resonance imaging (MRI).
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NASA Technical Reports Server (NTRS)
Sathyanarayanan, P. V.; Siems, W. F.; Jones, J. P.; Poovaiah, B. W.
2001-01-01
The existence of two molecular switches regulating plant chimeric Ca(2+)/calmodulin-dependent protein kinase (CCaMK), namely the C-terminal visinin-like domain acting as Ca(2+)-sensitive molecular switch and calmodulin binding domain acting as Ca(2+)-stimulated autophosphorylation-sensitive molecular switch, has been described (Sathyanarayanan, P. V., Cremo, C. R., and Poovaiah, B. W. (2000) J. Biol. Chem. 275, 30417-30422). Here we report the identification of Ca(2+)-stimulated autophosphorylation site of CCaMK by matrix-assisted laser desorption ionization time of flight-mass spectrometry. Thr(267) was confirmed as the Ca(2+)-stimulated autophosphorylation site by post-source decay experiments and by site-directed mutagenesis. The purified T267A mutant form of CCaMK did not show Ca(2+)-stimulated autophosphorylation, autophosphorylation-dependent variable calmodulin affinity, or Ca(2+)/calmodulin stimulation of kinase activity. Sequence comparison of CCaMK from monocotyledonous plant (lily) and dicotyledonous plant (tobacco) suggests that the autophosphorylation site is conserved. This is the first identification of a phosphorylation site specifically responding to activation by second messenger system (Ca(2+) messenger system) in plants. Homology modeling of the kinase and calmodulin binding domain of CCaMK with the crystal structure of calcium/calmodulin-dependent protein kinase 1 suggests that the Ca(2+)-stimulated autophosphorylation site is located on the surface of the kinase and far from the catalytic site. Analysis of Ca(2+)-stimulated autophosphorylation with increasing concentration of CCaMK indicates the possibility that the Ca(2+)-stimulated phosphorylation occurs by an intermolecular mechanism.
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Qian, Yawei; Yao, Wei; Yang, Tao; Yang, Yan; Liu, Yan; Shen, Qi; Zhang, Jian; Qi, Weipeng; Wang, Jianming
2017-10-01
Cholangiocarcinoma (CCA) is a highly malignant bile duct cancer that tends to invade and metastasize early. The epithelial-mesenchymal transition (EMT) has been implicated in cancer cell invasion and metastasis, as well as in cancer cell evasion of host immunity. In this study, we investigated the interaction between atypical protein kinase C-iota (aPKC-ι) and Snail in the regulation of EMT and its relationship to CCA immunosuppression. Our results demonstrated that aPKC-ι, Snail, and infiltrated immunosuppressive cells were significantly up-regulated in CCA tumor tissues and linked to poor prognosis. aPKC-ι induced EMT and immunosuppression by regulating Snail in vitro and in vivo, although aPKC-ι did not directly interact with Snail in coimmunoprecipitation experiments. To further clarify the molecular interaction between aPKC-ι and Snail in relation to EMT, quantitative iTRAQ-based phosphoproteomic analysis and liquid chromatography-tandem mass spectrometry were conducted to identify the substrates of aPKC-ι-dependent phosphorylation. Combined with coimmunoprecipitation, we showed that specificity protein 1 (Sp1) was directly phosphorylated by aPKC-ι on Ser59 (P-Sp1). Both Sp1 and P-Sp1 were up-regulated in CCA tumor tissues and associated with clinicopathological features and poor prognosis in CCA patients. Moreover, using chromatin immunoprecipitation assays, we found that P-Sp1 regulated Snail expression by increasing Sp1 binding to the Snail promoter. P-Sp1 also regulated aPKC-ι/Snail-induced EMT-like changes and immunosuppression in CCA cells. Our findings further indicated that CCA cells with EMT-like features appear to generate immunosuppressive natural T regulatory-like cluster of differentiation 4-positive (CD4 + )CD25 - cells rather than to increase CD4 + CD25 + natural T regulatory cells, in part by mediating T regulatory-inducible cytokines such as transforming growth factor β1 and interleukin 2. These results demonstrate that aPKC-ι promotes EMT and induces immunosuppression through the aPKC-ι/P-Sp1/Snail signaling pathway and may be a potential therapeutic target for CCA. (Hepatology 2017;66:1165-1182). © 2017 by the American Association for the Study of Liver Diseases.
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Broadband moth-eye antireflection coatings on silicon
NASA Astrophysics Data System (ADS)
Sun, Chih-Hung; Jiang, Peng; Jiang, Bin
2008-02-01
We report a bioinspired templating technique for fabricating broadband antireflection coatings that mimic antireflective moth eyes. Wafer-scale, subwavelength-structured nipple arrays are directly patterned on silicon using spin-coated silica colloidal monolayers as etching masks. The templated gratings exhibit excellent broadband antireflection properties and the normal-incidence specular reflection matches with the theoretical prediction using a rigorous coupled-wave analysis (RCWA) model. We further demonstrate that two common simulation methods, RCWA and thin-film multilayer models, generate almost identical prediction for the templated nipple arrays. This simple bottom-up technique is compatible with standard microfabrication, promising for reducing the manufacturing cost of crystalline silicon solar cells.
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Bioinspired broadband antireflection coatings on GaSb
NASA Astrophysics Data System (ADS)
Min, Wei-Lun; Betancourt, Amaury P.; Jiang, Peng; Jiang, Bin
2008-04-01
We report an inexpensive yet scalable templating technique for fabricating moth-eye antireflection gratings on gallium antimonide substrates. Non-close-packed colloidal monolayers are utilized as etching masks to pattern subwavelength-structured nipple arrays on GaSb. The resulting gratings exhibit superior broadband antireflection properties and thermal stability than conventional multilayer dielectric coatings. The specular reflection of the templated nipple arrays match with the theoretical predictions using a rigorous coupled-wave analysis model. The effect of the nipple shape and size on the antireflection properties has also been investigated by the same model. These biomimetic coatings are of great technological importance in developing efficient thermophotovoltaic cells.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelly, R.F.; Kravchenko, I.I.; Kuharik, J.C.
Widespread use of chromated copper arsenate (CCA) as a wood preservative has led to increasing public concern regarding possible toxic contamination of areas surrounding CCA-treated structures, e.g., decks, playground equipment, etc. Appreciable leaching of arsenic, chromium, and copper into soils adjacent to such structures has been demonstrated via standard techniques of analytical chemistry. The advantages of PIXE [rapid analysis, quick sample turnover, possible lower cost] suggest its application to this area of interest. PIXE studies in our laboratory of CCA-contaminated soil samples show good agreement with previous analyses of As, Cu, Cr, and other heavy-elemental content, with some variability inmore » diffusion rates.« less
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Coudert, Lucie; Blais, Jean-François; Mercier, Guy; Cooper, Paul; Janin, Amélie; Gastonguay, Louis
2014-01-01
In recent years, an efficient and economically attractive leaching process has been developed to remove metals from copper-based treated wood wastes. This study explored the applicability of this leaching process using chromated copper arsenate (CCA) treated wood samples with different initial metal loading and elapsed time between wood preservation treatment and remediation. The sulfuric acid leaching process resulted in the solubilization of more than 87% of the As, 70% of the Cr, and 76% of the Cu from CCA-chips and in the solubilization of more than 96% of the As, 78% of the Cr and 91% of the Cu from CCA-sawdust. The results showed that the performance of this leaching process might be influenced by the initial metal loading of the treated wood wastes and the elapsed time between preservation treatment and remediation. The effluents generated during the leaching steps were treated by precipitation-coagulation to satisfy the regulations for effluent discharge in municipal sewers. Precipitation using ferric chloride and sodium hydroxide was highly efficient, removing more than 99% of the As, Cr, and Cu. It appears that this leaching process can be successfully applied to remove metals from different CCA-treated wood samples and then from the effluents. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Crosstalk between the Circadian Clock and Innate Immunity in Arabidopsis
Zhang, Chong; Xie, Qiguang; Anderson, Ryan G.; Ng, Gina; Seitz, Nicholas C.; Peterson, Thomas; McClung, C. Robertson; McDowell, John M.; Kong, Dongdong; Kwak, June M.; Lu, Hua
2013-01-01
The circadian clock integrates temporal information with environmental cues in regulating plant development and physiology. Recently, the circadian clock has been shown to affect plant responses to biotic cues. To further examine this role of the circadian clock, we tested disease resistance in mutants disrupted in CCA1 and LHY, which act synergistically to regulate clock activity. We found that cca1 and lhy mutants also synergistically affect basal and resistance gene-mediated defense against Pseudomonas syringae and Hyaloperonospora arabidopsidis. Disrupting the circadian clock caused by overexpression of CCA1 or LHY also resulted in severe susceptibility to P. syringae. We identified a downstream target of CCA1 and LHY, GRP7, a key constituent of a slave oscillator regulated by the circadian clock and previously shown to influence plant defense and stomatal activity. We show that the defense role of CCA1 and LHY against P. syringae is at least partially through circadian control of stomatal aperture but is independent of defense mediated by salicylic acid. Furthermore, we found defense activation by P. syringae infection and treatment with the elicitor flg22 can feedback-regulate clock activity. Together this data strongly supports a direct role of the circadian clock in defense control and reveal for the first time crosstalk between the circadian clock and plant innate immunity. PMID:23754942
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Haonon, Ornuma; Rucksaken, Rucksak; Pinlaor, Porntip; Pairojkul, Chawalit; Chamgramol, Yaovalux; Intuyod, Kitti; Onsurathum, Sudarat; Khuntikeo, Narong; Pinlaor, Somchai
2016-03-01
To discover protein markers in chronic/advanced opisthorchiasis for the early detection of Opisthorchis viverrini (OV)-associated cholangiocarcinoma (CCA). Liver tissues derived from normal hamsters and those with chronic/advanced opisthorchiasis (n = 5 per group) were subjected to 2DE and LC-MS/MS. Candidate protein expression was confirmed in hamster models and human CCA tissue microarray (TMA) using immunohistochemistry and Western blot. Proteomics analysis detected 14-3-3 eta only in infected hamsters, not in uninfected controls. Immunohistochemistry and Western blot analysis confirmed low expression of 14-3-3 eta in normal hamster livers and demonstrated increased expression through time in infected livers. This protein was also observed in parasite organs, especially during the chronic phase of opisthorchiasis. Moreover, increased expression of 14-3-3 eta, relative to normal hamster livers, was observed during the early stage of CCA induced by OV infection and administration of N-nitrosodimethylamine. Immunohistochemical analysis of human TMA revealed that 14-3-3 eta was highly expressed in CCA (84.23%, 187/222 cases) but was not found in hepatocellular carcinoma or healthy liver tissues. 14-3-3 eta protein has potential as a screening and early diagnostic marker for CCA. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Cholangiocarcinoma — evolving concepts and therapeutic strategies
Rizvi, Sumera; Khan, Shahid A.; Hallemeier, Christopher L.; Kelley, Robin K.; Gores, Gregory J.
2018-01-01
Cholangiocarcinoma is a disease entity comprising diverse epithelial tumours with features of cholangiocyte differentiation: cholangiocarcinomas are categorized according to anatomical location as intrahepatic (iCCA), perihilar (pCCA), or distal (dCCA). Each subtype has a distinct epidemiology, biology, prognosis, and strategy for clinical management. The incidence of cholangiocarcinoma, particularly iCCA, has increased globally over the past few decades. Surgical resection remains the mainstay of potentially curative treatment for all three disease subtypes, whereas liver transplantation after neoadjuvant chemoradiation is restricted to a subset of patients with early stage pCCA. For patients with advanced-stage or unresectable disease, locoregional and systemic chemotherapeutics are the primary treatment options. Improvements in external-beam radiation therapy have facilitated the treatment of cholangiocarcinoma. Moreover, advances in comprehensive whole-exome and transcriptome sequencing have defined the genetic landscape of each cholangiocarcinoma subtype. Accordingly, promising molecular targets for precision medicine have been identified, and are being evaluated in clinical trials, including those exploring immunotherapy. Biomarker-driven trials, in which patients are stratified according to anatomical cholangiocarcinoma subtype and genetic aberrations, will be essential in the development of targeted therapies. Targeting the rich tumour stroma of cholangiocarcinoma in conjunction with targeted therapies might also be useful. Herein, we review the evolving developments in the epidemiology, pathogenesis, and management of cholangiocarcinoma. PMID:28994423
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NASA Astrophysics Data System (ADS)
Wang, Wu; Wang, Yong-Li; Chen, Mo; Chen, Liang; Zhang, Jian; Li, Yong-Dong; Li, Ming-Hua; Yuan, Guang-Yin
2016-11-01
Magnesium alloy covered stents have rarely been used in the common carotid artery (CCA). We evaluated the long-term efficacy of magnesium alloy covered stents in a lateral aneurysm model in rabbit CCA. Magnesium alloy covered stents (group A, n = 7) or Willis covered stents (group B, n = 5) were inserted in 12 New Zealand White rabbits and they were followed up for 12 months. The long-term feasibility for aneurysm occlusion was studied through angiograms; the changes in vessel area and lumen area were assessed with IVUS. Complete aneurysmal occlusion was achieved in all aneurysms. Angiography showed that the diameter of the stented CCA in group A at 6 and 12 months was significantly greater than the diameter immediately after stent placement. On intravascular ultrasound (IVUS) examination, the mean lumen area of the stented CCA in group A was significantly greater at 6 and 12 months than that immediately after stent placement; the mean lumen area was also significantly greater in group A than in group B at the same time points. The magnesium alloy covered stents proved to be an effective approach for occlusion of lateral aneurysm in the rabbit CCA; it provides distinct advantages that are comparable to that obtained with the Willis covered stent.
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Hepatoprotective effect of chitosan-caffeic acid conjugate against ethanol-treated mice.
Park, Soo Yeon; Ahn, Ginnae; Um, Ju Hyung; Han, Eui Jeong; Ahn, Chang-Bum; Yoon, Na Young; Je, Jae-Young
2017-10-02
The chitosan-caffeic acid (CCA) conjugate shows a hepatoprotective effect against oxidative stress-induced hepatic damage in cultured hepatocytes. The objective of this study is the verification of the hepatoprotective effect of the CCA in vivo against ethanol-induced liver injury in mice. The administration of ethanol resulted in the increase of the serum-aminotransferase activities (AST and ALT), triglycerides, total cholesterol, and lipid peroxidation. The CCA co-administration, however, significantly (p<0.05) ameliorated these serum biomarkers. The antioxidant-enzyme activities in the liver tissue, including those of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were significantly decreased by a chronic ethanol administration, whereas the hepatic lipid-peroxidation level was increased. Moreover, the chronic ethanol administration elevated the gene expression of pro-inflammatory cytokines such as tumor-necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver tissue. The CCA co-administration, however, significantly (p<0.05) increased the activities of the SOD, CAT, and GPx and caused the down-regulation of the TNF-α- and IL-6-gene expressions in the liver tissue. An histopathologic evaluation also supported the hepatoprotective effect of the CCA against ethanol-induced hepatotoxicity in the mice. Copyright © 2017 Elsevier GmbH. All rights reserved.
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Chemical mediation of coral larval settlement by crustose coralline algae
Tebben, J.; Motti, C. A; Siboni, Nahshon; Tapiolas, D. M.; Negri, A. P.; Schupp, P. J.; Kitamura, Makoto; Hatta, Masayuki; Steinberg, P. D.; Harder, T.
2015-01-01
The majority of marine invertebrates produce dispersive larvae which, in order to complete their life cycles, must attach and metamorphose into benthic forms. This process, collectively referred to as settlement, is often guided by habitat-specific cues. While the sources of such cues are well known, the links between their biological activity, chemical identity, presence and quantification in situ are largely missing. Previous work on coral larval settlement in vitro has shown widespread induction by crustose coralline algae (CCA) and in particular their associated bacteria. However, we found that bacterial biofilms on CCA did not initiate ecologically realistic settlement responses in larvae of 11 hard coral species from Australia, Guam, Singapore and Japan. We instead found that algal chemical cues induce identical behavioral responses of larvae as per live CCA. We identified two classes of CCA cell wall-associated compounds – glycoglycerolipids and polysaccharides – as the main constituents of settlement inducing fractions. These algae-derived fractions induce settlement and metamorphosis at equivalent concentrations as present in CCA, both in small scale laboratory assays and under flow-through conditions, suggesting their ability to act in an ecologically relevant fashion to steer larval settlement of corals. Both compound classes were readily detected in natural samples. PMID:26042834
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SSVEP recognition using common feature analysis in brain-computer interface.
Zhang, Yu; Zhou, Guoxu; Jin, Jing; Wang, Xingyu; Cichocki, Andrzej
2015-04-15
Canonical correlation analysis (CCA) has been successfully applied to steady-state visual evoked potential (SSVEP) recognition for brain-computer interface (BCI) application. Although the CCA method outperforms the traditional power spectral density analysis through multi-channel detection, it requires additionally pre-constructed reference signals of sine-cosine waves. It is likely to encounter overfitting in using a short time window since the reference signals include no features from training data. We consider that a group of electroencephalogram (EEG) data trials recorded at a certain stimulus frequency on a same subject should share some common features that may bear the real SSVEP characteristics. This study therefore proposes a common feature analysis (CFA)-based method to exploit the latent common features as natural reference signals in using correlation analysis for SSVEP recognition. Good performance of the CFA method for SSVEP recognition is validated with EEG data recorded from ten healthy subjects, in contrast to CCA and a multiway extension of CCA (MCCA). Experimental results indicate that the CFA method significantly outperformed the CCA and the MCCA methods for SSVEP recognition in using a short time window (i.e., less than 1s). The superiority of the proposed CFA method suggests it is promising for the development of a real-time SSVEP-based BCI. Copyright © 2014 Elsevier B.V. All rights reserved.
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Marches, R; Racila, E; Tucker, T F; Picker, L; Mongini, P; Hsueh, R; Vitetta, E S; Scheuermann, R H; Uhr, J W
1995-06-01
Polyclonal anti-IgM antibodies were more effective than monoclonal antibodies in inducing dormancy in SCID mice bearing a murine B lymphoma (BCL1). Under saturating conditions, both polyclonal and monoclonal anti-Ig antibodies induced cell cycle arrest (CCA) in both BCL1 cells and human B lymphoma cells (Daudi) but polyclonal antibodies were far more effective at inducing apoptosis. A mixture of several monoclonal antibodies specific for noncrossreactive epitopes on C mu mimicked the effects of a polyclonal anti-mu. Hypercrosslinking mIgM by a polyclonal antibody against the primary monoclonal anti-mu markedly increased apoptosis and CCA. Hence, the extent of crosslinking of IgM and the resultant singnalling may be a major factor in inducing and maintaining dormancy and in determining whether lymphoma cells respond by apoptosis or CCA. In contrast to mIgM, another B cell receptor, CD40, which induces CCA when crosslinked did not induce apoptosis after hypercrosslinking. The results are consistent with the hypothesis that aspects of the CCA and apoptotic pathways are independent. When anti-CD40 was added with anti-mu to Daudi cells, the proportion of cells undergoing apoptosis was increased.
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Study of the self-organization processes in lead sulfide quantum dots
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tarasov, S. A., E-mail: SATarasov@mail.ru; Aleksandrova, O. A.; Maksimov, A. I.
A procedure is described for the synthesis of nanoparticles based on lead chalcogenides. The procedure combines the synthesis of colloidal quantum dots (QDs) in aqueous solutions with simultaneous organization of the QDs into ordered arrays. The processes of the self-organization of QDs are analyzed at the nano- and microscopic levels by the photoluminescence method, atomic-force microscopy, and optical microscopy.
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Chan, Emory M; Xu, Chenxu; Mao, Alvin W; Han, Gang; Owen, Jonathan S; Cohen, Bruce E; Milliron, Delia J
2010-05-12
While colloidal nanocrystals hold tremendous potential for both enhancing fundamental understanding of materials scaling and enabling advanced technologies, progress in both realms can be inhibited by the limited reproducibility of traditional synthetic methods and by the difficulty of optimizing syntheses over a large number of synthetic parameters. Here, we describe an automated platform for the reproducible synthesis of colloidal nanocrystals and for the high-throughput optimization of physical properties relevant to emerging applications of nanomaterials. This robotic platform enables precise control over reaction conditions while performing workflows analogous to those of traditional flask syntheses. We demonstrate control over the size, size distribution, kinetics, and concentration of reactions by synthesizing CdSe nanocrystals with 0.2% coefficient of variation in the mean diameters across an array of batch reactors and over multiple runs. Leveraging this precise control along with high-throughput optical and diffraction characterization, we effectively map multidimensional parameter space to tune the size and polydispersity of CdSe nanocrystals, to maximize the photoluminescence efficiency of CdTe nanocrystals, and to control the crystal phase and maximize the upconverted luminescence of lanthanide-doped NaYF(4) nanocrystals. On the basis of these demonstrative examples, we conclude that this automated synthesis approach will be of great utility for the development of diverse colloidal nanomaterials for electronic assemblies, luminescent biological labels, electroluminescent devices, and other emerging applications.
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Effect of verteporfin-PDT on the Notch signaling pathway in cholangiocarcinoma (CCA) cell lines
NASA Astrophysics Data System (ADS)
Cerec, Virginie; Andreola, Fausto; Pereira, Stephen P.
2009-06-01
Accumulating preclinical and clinical evidence supports a pro-oncogenic function for Notch signaling in several solid tumors. Therefore, Notch inhibitory agents, such as gamma-secretase inhibitors (GSI), are being investigated as cancer therapeutic agents and a potential adjuvant to conventional chemo/radiotherapy. To date, no in vitro data are available on the cellular response and effect of either photodynamic therapy (PDT) or GSI on human cholangiocarcinoma (CCA). Consequently, we aimed to study the: (i) constitutive expression of Notch signaling pathway in CCA cell lines; (ii) response to Verteporfin-PDT and to GSI, as single agents on CCA cell lines; (iii) effect of Verteporfin-PDT on Notch signaling pathway expression. Expression of Notch signaling components was studied in two cholangiocarcinoma cell lines, HuCCT1 and TFK-1 (intra- and extrahepatic, respectively). No difference in basal expression of Notch1, 2 and Jagged1 was observed in either cell line. In contrast, Notch3 was found to be weakly and highly expressed in HuCCT1 and TFK-1 cells, respectively - supporting our recent microarray data which showed Notch3 overexpression in biliary brushings from patients with extrahepatic CCA. HuCCT1 and TFK-1 differentially responded to Verteporfin-PDT treatment; preliminary data showed no clear effect of GSI on proliferation/apoptosis in either cell line following short exposure (6 and 24h). Following Verteporfin-PDT, Notch1, 2 and Jagged-1 expression was down-regulated in both cell lines, while Notch3 expression was unaffected in HuCCT1 cells and down-regulated in TFK-1 cells. The Notch signaling pathway could represent a potential target for combination therapy in CCA treatment.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Yun-Fei; Yang, Xiao-Qing; Lu, Xiao-Fei
Highlights: • FGFR4 is significantly related with N stage in IHCC, with T stage and TNM stage in PHCC. • FGFR4 is an independent prognostic factor in IHCC and PHCC. • FGFR4 promotes proliferation, invasion and EMT in cholangiocarinoma cell lines. • Inhibitor AP24354 can decrease proliferation, invasion and induce apoptosis of CCA. - Abstract: Fibroblast growth factor receptor 4 (FGFR4) is related to poor prognosis of several cancers, but the correlation between FGFR4 expression and cholangiocarcinoma (CCA) has not been well elucidated. We investigated the expression of FGFR4 in 83 intrahepatic cholangiocarcinomas (IHCCs), 75 perihilar cholangiocarcinomas (PHCCs) and 41more » distal cholangiocarcinomas (DCCs) by immunohistochemistry (IHC), and subsequently evaluated association of FGFR4 with clinicopathologic parameters and survival rate. The rate of FGFR4 higher expression was 61.4% (51/83) in IHCCs, 53.3% (40/75) in PHCCs and 56.1% (23/41) in DCCs. FGFR4 expression was significantly related to poor prognosis of IHCC (P = 0.002) and PHCC (P = 0.019) with univariate analysis, and also identified as an independent prognostic factor in IHCC (P = 0.045) and PHCC (P = 0.049) with multivariate analysis. Additionally, with functional assays in vitro, we found FGFR4 can induce proliferation, invasion and epithelial–mesenchymal transition (EMT) of CCA cell lines with FGF19 stimulation. Moreover, FGFR4 inhibitor AP24354 can suppress proliferation, invasion and induce apoptosis of CCA cells. In conclusion, FGFR4 expression can be identified as a significant independent prognostic biomarker of IHCC and PHCC. FGFR4 played a pivotal role in proliferation, invasion and EMT of CCA. FGFR4 inhibitor can suppress proliferation, invasion and induce apoptosis of CCA, indicating that FGFR4 may act as a potential therapeutic target.« less
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Sugihara, Takaaki; Werneburg, Nathan W; Hernandez, Matthew C; Yang, Lin; Kabashima, Ayano; Hirsova, Petra; Yohanathan, Lavanya; Sosa, Carlos; Truty, Mark Joseph; Vasmatzis, George; Gores, Gregory J; Smoot, Rory L
2018-06-14
The hippo pathway effector, Yes-associated protein (YAP) is a transcriptional co-activator implicated in cholangiocarcinoma (CCA) pathogenesis. YAP is known to be regulated by a serine/threonine kinase relay module (MST1/2 - LATS1/2) culminating in phosphorylation of YAP at Serine 127 (S127) and cytoplasmic sequestration. However, YAP also undergoes tyrosine phosphorylation, and the role of tyrosine phosphorylation in YAP regulation remains unclear. Herein, YAP regulation by tyrosine phosphorylation was examined in human and mouse CCA cells, as well as patient-derived xenograft (PDX) models. YAP was phosphorylated on tyrosine 357 (Y357) in CCA cell lines and PDX models. SRC family kinase (SFK) inhibition with dasatinib resulted in loss of YAPY357 phosphorylation, promoted its translocation from the nucleus to the cytoplasm, and reduced YAP target gene expression; including cell lines expressing a LATS1/2-resistant YAP mutant in which all serine residues were mutated to alanine. Consistent with these observations, precluding YAPY357 phosphorylation by site-directed mutagenesis (YAPY357F) excluded YAP from the nucleus. Targeted siRNA experiments identified LCK as the SFK that most potently mediated YAPY357 phosphorylation. Likewise, inducible CRISPR/Cas9-targeted LCK deletion decreased YAPY357 phosphorylation and its nuclear localization. The importance of LCK in CCA biology was demonstrated by clinical observations suggesting LCK expression levels were associated with early tumor recurrence following resection of CCA. Finally, dasatinib displayed therapeutic efficacy in PDX models. Demonstration of targetable, LCK-mediated YAP tyrosine phosphorylation in CCA regulating YAP's nuclear retention and oncogenic activity. Copyright ©2018, American Association for Cancer Research.
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NASA Astrophysics Data System (ADS)
Peiris, T. S. G.; Nanayakkara, K. A. D. S. A.
2017-09-01
Mathematics plays a key role in engineering sciences as it assists to develop the intellectual maturity and analytical thinking of engineering students and exploring the student academic performance has received great attention recently. The lack of control over covariates motivates the need for their adjustment when measuring the degree of association between two sets of variables in Canonical Correlation Analysis (CCA). Thus to examine the individual effects of mathematics in Level 1 and Level 2 on engineering performance in Level 2, two adjusted analyses in CCA: Part CCA and Partial CCA were applied for the raw marks of engineering undergraduates for three different disciplines, at the Faculty of Engineering, University of Moratuwa, Sri Lanka. The joint influence of mathematics in Level 1 and Level 2 is significant on engineering performance in Level 2 irrespective of the engineering disciplines. The individual effect of mathematics in Level 2 is significantly higher compared to the individual effect of mathematics in Level 1 on engineering performance in Level 2. Furthermore, the individual effect of mathematics in Level 1 can be negligible. But, there would be a notable indirect effect of mathematics in Level 1 on engineering performance in Level 2. It can be concluded that the joint effect of mathematics in both Level 1 and Level 2 is immensely beneficial to improve the overall academic performance at the end of Level 2 of the engineering students. Furthermore, it was found that the impact mathematics varies among engineering disciplines. As partial CCA and partial CCA are not widely explored in applied work, it is recommended to use these techniques for various applications.
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Chaosuwannakit, N; Makarawate, P
2018-01-01
Primary evaluation of patients with pulmonary atresia with ventricular septal defect (PA-VSD) traditionally relies upon echocardiography and conventional cardiac angiography (CCA). Cardiac angiography is considered the gold standard for delineation of anatomy in children with PA-VSD. Data comparing CCA and dual-source multidetector-row computed tomography angiography (MDCT) in PA-VSD patients is limited. The objective of this study was to test the hypothesis that MDCT is equivalent to CCA for anatomic delineation in these patients. Twenty-eight patients with PA-VSD underwent CCA and MDCT in close proximity to each other without interval therapy. A retrospective review of these 28 patients was performed. All MDCT data of pulmonary artery morphology, major aortopulmonary collateral arteries (MAPCAs) and type of blood supply (dual vs. single supply) were evaluated by blinded experts and results were compared with CCA. Twenty-eight patients had adequate size right and left pulmonary arteries (21 confluent and 7 non-confluent). Seven patients had complete absence of native pulmonary artery and 3 patients had stenosis of distal branches of pulmonary arteries; all had MAPCAs from descending thoracic aorta and/or subclavian arteries. Sensitivity, specificity, positive and negative predictive value of MDCT for detecting confluent of pulmonary arteries, absence of native pulmonary artery and stenosis of pulmonary arteries were all 100%. Moreover, accuracy of detecting MAPCAs was excellent. These results suggest that MDCT and CCA are equivalent in their ability to delineate pulmonary artery anatomy and MAPCAs. Dual source MDCT provides high diagnostic accuracy in evaluation of pulmonary blood supply in patients with PA-VSD and allows precise characterisation of the condition of pulmonary arteries and MAPCAs which is of paramount importance in managing patients with PA-VSD. (Folia Morphol 2018; 77, 1: 116-122).
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[EFFECTS OF VOLUNTARY INTAKE OF FLUIDS (WATER AND SPORTS DRINK) IN AMATEUR MOUNTAIN RUNNERS].
Nebot, Vicente; Drehmer, Eraci; Elvira, Laura; Sales, Sonia; Sanchís, Carlos; Esquius, Laura; Pablos, Ana
2015-11-01
21 K and 1 000 m ascent trail-running races can be dangerous if an appropriate liquid replacement isn't maintained. know trail-runners level of dehydration and assess the differences between ad libitum water (CcA) and sport drink (CcB) hydration after a trail running race. 18 subjects, mean age 31.9 (±2.8) and %MG 10.53 (±2.8), completed CcA or CcB. CcA and CcB effects on Weight (P), Fat Mass (MG), Glucose (GL), Lactate (LT), Systolic (TAS) and Diastolic Arterial Tension (TAD), Heart Rate (PPM) and Tympanic Temperature (Tª) were assessed. All measurements were taken at the start (T1) and the finish (T2) of each race. A Friedman ANOVA test was used to calculate the effect of CcA and CcB on each variable. Differences between race time (TC), % bodyweight loss (%PP) and liquid ingestion (LI) were assessed with a Wilcoxon test. All statistical analysis were conducted with SPSS version 20.0 (IBM, Somers, NY, USA). mean %PP was 2.967 (± 0.969) and 2.883 (± 0.730) for CcA and CcB respectively. No significant differences were found between %PP and LI (p > .05) between races. Significant changes were found in P, %MG, GL, L, TAS and PPM between T1 and T2 in CcA condition. While only significant changes in P and PPM were stabilised between T1 and T2 in CcB condition. neither water or sport drink ingestion avoid trail-runners to reach a dehydrated state. However, dehydration effects seems to be more serious when only water is ingested. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
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Ferreira, Fernanda Teixeira; Fidelis, Thiago André; Pereira, Thiago Almeida; Otoni, Alba; Queiroz, Leonardo Campos; Amâncio, Frederico Figueiredo; Antunes, Carlos Maurício; Lambertucci, José Roberto
2017-01-01
The Kato-Katz technique is the standard diagnostic test for Schistosoma mansoni infection in rural areas. However, the utility of this method is severely limited by the day-to-day variability in host egg excretion in the stool. In high-transmission areas, the point-of-care circulating cathodic antigen (POC-CCA) urine assay has proven to be a reliable test. However, investigations of the reliability of the POC-CCA assay in low-transmission regions are under way. This study aimed to evaluate the sensitivity and specificity of the POC-CCA assay and the morbidity of schistosomiasis in a low-endemic area in Brazil. Pains City is a low-transmission zone for schistosomiasis. A total of 300 subjects aged 7-76 years were randomly selected for the POC-CCA cassette test. For S. mansoni diagnosis, three stool samples on six slides were compared with one urine sample for each subject. The sensitivity and specificity in the absence of a gold standard were calculated using latent class analysis. Clinical examinations and abdominal ultrasounds were performed in 181 volunteers to evaluate morbidity associated with schistosomiasis. The sensitivity and specificity of the Kato-Katz technique were 25.6% and 94.6%, respectively. By contrast, the sensitivity and specificity of the POC-CCA assay were 68.1% and 72.8%, respectively. Hepatosplenic schistosomiasis was diagnosed in two patients (1.1%). Overall, the POC-CCA urine assay proved to be a useful test for diagnosing S. mansoni in a low-endemic area in Brazil. Severe clinical forms of schistosomiasis can be present even in such low-endemic areas.
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Gao, Zhifan; Li, Yanjie; Sun, Yuanyuan; Yang, Jiayuan; Xiong, Huahua; Zhang, Heye; Liu, Xin; Wu, Wanqing; Liang, Dong; Li, Shuo
2018-01-01
The motion of the common carotid artery (CCA) wall has been established to be useful in early diagnosis of atherosclerotic disease. However, tracking the CCA wall motion from ultrasound images remains a challenging task. In this paper, a nonlinear state-space approach has been developed to track CCA wall motion from ultrasound sequences. In this approach, a nonlinear state-space equation with a time-variant control signal was constructed from a mathematical model of the dynamics of the CCA wall. Then, the unscented Kalman filter (UKF) was adopted to solve the nonlinear state transfer function in order to evolve the state of the target tissue, which involves estimation of the motion trajectory of the CCA wall from noisy ultrasound images. The performance of this approach has been validated on 30 simulated ultrasound sequences and a real ultrasound dataset of 103 subjects by comparing the motion tracking results obtained in this study to those of three state-of-the-art methods and of the manual tracing method performed by two experienced ultrasound physicians. The experimental results demonstrated that the proposed approach is highly correlated with (intra-class correlation coefficient ≥ 0.9948 for the longitudinal motion and ≥ 0.9966 for the radial motion) and well agrees (the 95% confidence interval width is 0.8871 mm for the longitudinal motion and 0.4159 mm for the radial motion) with the manual tracing method on real data and also exhibits high accuracy on simulated data (0.1161 ~ 0.1260 mm). These results appear to demonstrate the effectiveness of the proposed approach for motion tracking of the CCA wall.
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SU-F-T-676: Measurement of Hydroxyl Radicals in Radiolized Water Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ouyang, Z; Ngwa, W; Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA
2016-06-15
Purpose: Hydroxyl radicals can be produced within tissue by radiation therapy, and they are largely responsible for DNA damage and cell killing. Coumarin-3-carboxylic acid (3-CCA) and crystal violet are reported to react with hydroxyl radicals and can be used for fluorescence and absorbance measurements, respectively. This study assesses the ability of hydroxyl measurement for both 3-CCA and crystal violet in radiolized water systems in order to provide dosimetric information in radiation chemistry and radiation biology experiments. Methods: 3-CCA and crystal violet were both dissolved in phosphate buffered saline (PBS, pH 7.4) with final concentrations 0.5 mg/mL and 0.05 mg/mL. 3-CCAmore » and control solutions (PBS only) were loaded in black bottom 96-well plates. Crystal violet and control solutions were loaded in clear bottom 96-well plates. The prepared solutions were irradiated at 2 Gy using a small animal radiation research platform. Fluorescence reading with 360 nm excitation wavelength and 485 nm emission wavelength was done for 3-CCA, and absorbance reading at wavelength 580 nm was done for crystal violet before and after radiation. Results: 3-CCA showed clear difference in fluorescence before and after radiation, which suggested hydroxyl production during radiation. However, crystal violet absorbance at 580 nm was not changed significantly by radiation. Conclusion: The overall conclusion is that 3-CCA can be used for hydroxyl measurement in radiolized water systems, while crystal violet cannot, although crystal violet is reported widely to react with hydroxyl radicals produced in Fenton reactions. Possible reasons could relate to reaction pH.« less
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Toma, Mana; Loget, Gabriel; Corn, Robert M
2014-07-23
Tunable hydrophobic/hydrophilic flexible Teflon nanocone array surfaces were fabricated over large areas (cm(2)) by a simple two-step method involving the oxygen plasma etching of a colloidal monolayer of polystyrene beads on a Teflon film. The wettability of the nanocone array surfaces was controlled by the nanocone array dimensions and various additional surface modifications. The resultant Teflon nanocone array surfaces were hydrophobic and adhesive (a "gecko" type of surface on which a water droplet has a high contact angle but stays in place) with a contact angle that correlated with the aspect ratio/sharpness of the nanocones. The surfaces switched to a superhydrophobic or "lotus" type of surface when hierarchical nanostructures were created on Teflon nanocones by modifying them with a gold nanoparticle (AuNPs) film. The nanocone array surfaces could be made superhydrophobic with a maximum contact angle of 160° by the further modification of the AuNPs with an octadecanethiol (C18SH) monolayer. Additionally, these nanocone array surfaces became hydrophilic when the nanocone surfaces were sequentially modified with AuNPs and hydrophilic polydopamine (PDA) layers. The nanocone array surfaces were tested for two potential applications: self-cleaning superhydrophobic surfaces and for the passive dispensing of aqueous droplets onto hybrid superhydrophobic/hydrophilic microarrays.
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Linux thin-client conversion in a large cardiology practice: initial experience.
Echt, Martin P; Rosen, Jordan
2004-01-01
Capital Cardiology Associates (CCA) is a single-specialty cardiology practice with offices in New York and Massachusetts. In 2003, CCA converted its IT system from a Microsoft-based network to a Linux network employing Linux thin-client technology with overall positive outcomes.
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Sullivan, D.J.
1997-01-01
Canonical correspondence analysis (CCA) revealed that soil credibility was a significant predictor of species composition. Though not statistically significant, land use, soil permeability, and bedrock permeability also were indicated as predictors of fish-species composition by CCA.
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Mita, Tomoya; Katakami, Naoto; Shiraiwa, Toshihiko; Yoshii, Hidenori; Kuribayashi, Nobuichi; Osonoi, Takeshi; Kaneto, Hideaki; Kosugi, Keisuke; Umayahara, Yutaka; Gosho, Masahiko; Shimomura, Iichiro; Watada, Hirotaka
2017-01-09
The effect of hypoglycemia on the progression of atherosclerosis in patients with type 2 diabetes mellitus (T2DM) remains largely unknown. This is a post hoc analysis of a randomized trial to investigate the relationship between hypoglycemic episodes and changes in carotid intima-media thickness (IMT). Among 274 study subjects, 104 patients experienced hypoglycemic episodes. Increases in the mean IMT and left maximum IMT of the common carotid arteries (CCA) were significantly greater in patients with hypoglycemia compared to those without hypoglycemia. Classification of the patients into three groups according to the frequency of hypoglycemic episodes showed that high frequency of hypoglycemic events was associated with increases in mean IMT-CCA, and left max-IMT-CCA and right max-IMT-CCA. In addition, repetitive episodes of hypoglycemia were associated with a reduction in the beneficial effects of sitagliptin on carotid IMT. Our data suggest that frequency of hypoglycemic episodes was associated with changes in carotid atherosclerosis.
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Nygren, O; Nilsson, C A; Lindahl, R
1992-10-01
CCA-impregnated timber contains copper, chromium and arsenic (CCA), and occupational exposure to wood dust as well as the CCA compounds may occur in work with such timber. Dust from commercially available impregnated wood has been found to contain hexavalent chromium, which is regarded as a carcinogen. Apart from determinations of the total amounts of the CCA compounds, specific determination of hexavalent chromium is therefore essential. Selective methods have been applied for control of the work environment in six joinery shops. The mean exposure to wood dust was found to be below 1 mg m-3. The mean airborne concentration of arsenic around various types of joinery machines was in the range from 0.54 to 3.1 micrograms m-3. No hexavalent chromium was detected in any samples and no increased concentrations of arsenic were found in urine from the workers. The presence of arsenic in the work-room air must be considered for appropriate assessment of the occupational environment in joinery shops.
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Ngamsom, Supak; Arayasantiparb, Raweewan; Pornprasertsuk-Damrongsri, Suchaya; Sureephong, Boonchoo
2015-11-01
The aim of the present study was to evaluate the correlation between calcified carotid atheromas (CCA) detected on digital panoramic radiographs and underlying systemic diseases. Panoramic radiographs and underlying systemic diseases of retained mandibular denture implants in 265 patients (56 males, 209 females) aged over 50 years were retrospectively evaluated at the Dental Unit of Prasat Neurological Institute, Bangkok, Thailand. The mean age of the patients was 71 ± 7.1 years. The prevalence of CCA was 38.49%. The major underlying systemic diseases were hypertension, hyperlipidemia, diabetes mellitus, and cardiovascular diseases (CVD), respectively. No relationship was found among these four systemic diseases in detecting CCA on panoramic radiographs. Similar findings were also observed in patients with only one systemic disease versus in combination with other diseases. The presence of CCA on dental panoramic radiographs was not found to be related to the presence of underlying systemic diseases, including hypertension, hyperlipidemia, diabetes mellitus, and CVD. © 2014 Wiley Publishing Asia Pty Ltd.
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NASA Astrophysics Data System (ADS)
Marietta, M. L.; Fowle, D. A.; Roberts, J. A.
2008-12-01
Pressure treated lumber (CCA) has been used in a variety of structures for over seven decades, but recent concerns have been raised about leaching of metals such as chromium (Cr) and arsenic (As) into proximal soils and water supplies. Pressure treated lumber abundance and its continued use necessitate a thorough understanding of metal release and sequestration in the subsurface. To date, no long-term, in situ study on the migration of CCA compounds from lumber has been performed. Barro Colorado Island, Panama is the site of several previous CCA studies and provides an opportunity to investigate the long-term (>70 years) effects of pressure treated lumber in oxisols, where high rainfall and warm temperatures may represent an end-member condition for the leaching and mobility of these metals. Soil samples from CCA and control sites were measured for Cr, As, Cu, Zn, and Fe abundances, microbial biomass and community structure via phospholipid fatty acid analysis, along with basic soil properties. CCA lumber samples were also characterized for their metal abundance. Lumber treated with zinc meta-arsenite displayed advanced decay with elevated As, Cu, and Zn concentrations observed in the adjacent soil. Increased soil organic matter and microbial biomass correlate to decreases in Fe and Fe-associated metals compared to the control. High As concentrations persist to <1 m of the source. Lumber treated with potassium dichromate contained high chromium concentrations and displayed little decay, however, soil concentrations of Cr, Fe, and Cu were generally less than control soils. Over these same intervals, soil organic matter and microbial biomass increased, particularly the fraction of metal reducing bacteria (MRB). We hypothesize that organic carbon loading from lumber stimulates MRB, leading to mobilization of Fe and Fe-associated metals from these oxide-rich soils. Principal component analysis of PLFA data confirms a distinction between controls and samples with elevated metal abundance at each site. This study provides fundamental insight into the long-term persistence of CCA compounds in Fe-rich soils and could serve in practical applications related to CCA contamination.
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Lo, Nathan C; Coulibaly, Jean T; Bendavid, Eran; N'Goran, Eliézer K; Utzinger, Jürg; Keiser, Jennifer; Bogoch, Isaac I; Andrews, Jason R
2016-08-01
A key epidemiologic feature of schistosomiasis is its focal distribution, which has important implications for the spatial targeting of preventive chemotherapy programs. We evaluated the diagnostic accuracy of a urine pooling strategy using a point-of-care circulating cathodic antigen (POC-CCA) cassette test for detection of Schistosoma mansoni, and employed simulation modeling to test the classification accuracy and efficiency of this strategy in determining where preventive chemotherapy is needed in low-endemicity settings. We performed a cross-sectional study involving 114 children aged 6-15 years in six neighborhoods in Azaguié Ahoua, south Côte d'Ivoire to characterize the sensitivity and specificity of the POC-CCA cassette test with urine samples that were tested individually and in pools of 4, 8, and 12. We used a Bayesian latent class model to estimate test characteristics for individual POC-CCA and quadruplicate Kato-Katz thick smears on stool samples. We then developed a microsimulation model and used lot quality assurance sampling to test the performance, number of tests, and total cost per school for each pooled testing strategy to predict the binary need for school-based preventive chemotherapy using a 10% prevalence threshold for treatment. The sensitivity of the urine pooling strategy for S. mansoni diagnosis using pool sizes of 4, 8, and 12 was 85.9%, 79.5%, and 65.4%, respectively, when POC-CCA trace results were considered positive, and 61.5%, 47.4%, and 30.8% when POC-CCA trace results were considered negative. The modeled specificity ranged from 94.0-97.7% for the urine pooling strategies (when POC-CCA trace results were considered negative). The urine pooling strategy, regardless of the pool size, gave comparable and often superior classification performance to stool microscopy for the same number of tests. The urine pooling strategy with a pool size of 4 reduced the number of tests and total cost compared to classical stool microscopy. This study introduces a method for rapid and efficient S. mansoni prevalence estimation through examining pooled urine samples with POC-CCA as an alternative to widely used stool microscopy.
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Coulibaly, Jean T.; Bendavid, Eran; N’Goran, Eliézer K.; Utzinger, Jürg; Keiser, Jennifer; Bogoch, Isaac I.; Andrews, Jason R.
2016-01-01
Background A key epidemiologic feature of schistosomiasis is its focal distribution, which has important implications for the spatial targeting of preventive chemotherapy programs. We evaluated the diagnostic accuracy of a urine pooling strategy using a point-of-care circulating cathodic antigen (POC-CCA) cassette test for detection of Schistosoma mansoni, and employed simulation modeling to test the classification accuracy and efficiency of this strategy in determining where preventive chemotherapy is needed in low-endemicity settings. Methodology We performed a cross-sectional study involving 114 children aged 6–15 years in six neighborhoods in Azaguié Ahoua, south Côte d’Ivoire to characterize the sensitivity and specificity of the POC-CCA cassette test with urine samples that were tested individually and in pools of 4, 8, and 12. We used a Bayesian latent class model to estimate test characteristics for individual POC-CCA and quadruplicate Kato-Katz thick smears on stool samples. We then developed a microsimulation model and used lot quality assurance sampling to test the performance, number of tests, and total cost per school for each pooled testing strategy to predict the binary need for school-based preventive chemotherapy using a 10% prevalence threshold for treatment. Principal Findings The sensitivity of the urine pooling strategy for S. mansoni diagnosis using pool sizes of 4, 8, and 12 was 85.9%, 79.5%, and 65.4%, respectively, when POC-CCA trace results were considered positive, and 61.5%, 47.4%, and 30.8% when POC-CCA trace results were considered negative. The modeled specificity ranged from 94.0–97.7% for the urine pooling strategies (when POC-CCA trace results were considered negative). The urine pooling strategy, regardless of the pool size, gave comparable and often superior classification performance to stool microscopy for the same number of tests. The urine pooling strategy with a pool size of 4 reduced the number of tests and total cost compared to classical stool microscopy. Conclusions/Significance This study introduces a method for rapid and efficient S. mansoni prevalence estimation through examining pooled urine samples with POC-CCA as an alternative to widely used stool microscopy. PMID:27504954
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Confined surface plasmon sensors based on strongly coupled disk-in-volcano arrays.
Ai, Bin; Wang, Limin; Möhwald, Helmuth; Yu, Ye; Zhang, Gang
2015-02-14
Disk-in-volcano arrays are reported to greatly enhance the sensing performance due to strong coupling in the nanogaps between the nanovolcanos and nanodisks. The designed structure, which is composed of a nanovolcano array film and a disk in each cavity, is fabricated by a simple and efficient colloidal lithography method. By tuning structural parameters, the disk-in-volcano arrays show greatly enhanced resonances in the nanogaps formed by the disks and the inner wall of the volcanos. Therefore they respond to the surrounding environment with a sensitivity as high as 977 nm per RIU and with excellent linear dependence on the refraction index. Moreover, through mastering the fabrication process, biological sensing can be easily confined to the cavities of the nanovolcanos. The local responsivity has the advantages of maximum surface plasmon energy density in the nanogaps, reducing the sensing background and saving expensive reagents. The disk-in-volcano arrays also possess great potential in applications of optical and electrical trapping and single-molecule analysis, because they enable establishment of electric fields across the gaps.
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Plasmonic Photovoltaic Cells with Dual-Functional Gold, Silver, and Copper Half-Shell Arrays.
Wu, Ling; Kim, Gyu Min; Nishi, Hiroyasu; Tatsuma, Tetsu
2017-09-12
Solid-state photovoltaic cells based on plasmon-induced charge separation (PICS) have attracted growing attention during the past decade. However, the power conversion efficiency (PCE) of the previously reported devices, which are generally loaded with dispersed metal nanoparticles as light absorbers, has not been sufficiently high. Here we report simpler plasmonic photovoltaic cells with interconnected Au, Ag, and Cu half-shell arrays deposited on SiO 2 @TiO 2 colloidal crystals, which serve both as a plasmonic light absorber and as a current collector. The well-controlled and easily prepared plasmonic structure allows precise comparison of the PICS efficiency between different plasmonic metal species. The cell with the Ag half-shell array has higher photovoltaic performance than the cells with Au and Cu half-shell arrays because of the high population of photogenerated energetic electrons, which gives a high electron injection efficiency and suppressed charge recombination probability, achieving the highest PCE among the solid-state PICS devices even without a hole transport layer.
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NASA Astrophysics Data System (ADS)
Désières, Yohan; Chen, Ding Yuan; Visser, Dennis; Schippers, Casper; Anand, Srinivasan
2018-06-01
Colloidal TiO2 nanoparticles were used for embossing of composite microcone arrays on III-Nitride vertical-thin-film blue light emitting diodes (LEDs) as well as on silicon, glass, gallium arsenide, and gallium nitride surfaces. Ray tracing simulations were performed to optimize the design of microcones for light extraction and to explain the experimental results. An optical power enhancement of ˜2.08 was measured on III-Nitride blue LEDs embossed with a hexagonal array of TiO2 microcones of ˜1.35 μm in height and ˜2.6 μm in base width, without epoxy encapsulation. A voltage increase in ˜70 mV at an operating current density of ˜35 A/cm2 was measured for the embossed LEDs. The TiO2 microcone arrays were embossed on functioning LEDs, using low pressures (˜100 g/cm2) and temperatures ≤100 °C.
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NASA Astrophysics Data System (ADS)
Liu, Wendong; Liu, Xueyao; Fangteng, Jiaozi; Wang, Shuli; Fang, Liping; Shen, Huaizhong; Xiang, Siyuan; Sun, Hongchen; Yang, Bai
2014-10-01
This paper presents a facile method to fabricate bioinspired polyethylene terephthalate (PET) nanocone arrays via colloidal lithography. The aspect ratio (AR) of the nanocones can be finely modulated ranging from 1 to 6 by regulating the etching time. The samples with the AR value of 6 can present underwater superoleophobicity with the underwater oil contact angle (OCA) of 171.8°. The as-prepared PET nanocone arrays perform anti-bioadhesion behavior, which inhibits the formation of the actin cytoskeleton when it used as the substrate for cell culture. Moreover, the oil wettability is temperature controlled after modifying the PET nanocone arrays with PNIPAAm film, and the oil wettability of the functionalized nanocone arrays can be transformed from the superoleophobic state with OCA about 151° to the oleophilic state with OCA about 25° reversibly. Due to the high-throughput, parallel fabrication and cost-efficiency of this method, it will be favourable for researchers to introduce oleophobic properties to various substrate and device surfaces. Due to the superoleophobicity and simple functionalizing properties, the PET nanocone arrays are very promising surfaces for anti-adhesion, self-cleaning and have potential applications in material, medical, and biological fields.This paper presents a facile method to fabricate bioinspired polyethylene terephthalate (PET) nanocone arrays via colloidal lithography. The aspect ratio (AR) of the nanocones can be finely modulated ranging from 1 to 6 by regulating the etching time. The samples with the AR value of 6 can present underwater superoleophobicity with the underwater oil contact angle (OCA) of 171.8°. The as-prepared PET nanocone arrays perform anti-bioadhesion behavior, which inhibits the formation of the actin cytoskeleton when it used as the substrate for cell culture. Moreover, the oil wettability is temperature controlled after modifying the PET nanocone arrays with PNIPAAm film, and the oil wettability of the functionalized nanocone arrays can be transformed from the superoleophobic state with OCA about 151° to the oleophilic state with OCA about 25° reversibly. Due to the high-throughput, parallel fabrication and cost-efficiency of this method, it will be favourable for researchers to introduce oleophobic properties to various substrate and device surfaces. Due to the superoleophobicity and simple functionalizing properties, the PET nanocone arrays are very promising surfaces for anti-adhesion, self-cleaning and have potential applications in material, medical, and biological fields. Electronic supplementary information (ESI) available: The optical microscopy image of the self-assembled 2D PS microspheres over a large area, the diameter of the PS microsphere is 580 nm; The top-view SEM image of the PET nanocone arrays over a large area, the AR of the nanocone is 6; The SEM image of the PET nanocone arrays obtained after 30 min etching; The optical image of the water droplet on the PET nanocone arrays with an AR of 6; The schematic illustration of the nanocone arrays modification with PNIPAAm; High resolution XPS spectra of the PNIPAAm modified PET nanocone arrays. See DOI: 10.1039/c4nr04471a
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Electrophoretic nanotechnology of composite electrodes for electrochemical supercapacitors.
Su, Y; Zhitomirsky, I
2013-02-14
The electrophoretic deposition (EPD) method has been developed for the fabrication of MnO(2)-multiwalled carbon nanotube (MWCNT) films for application in electrochemical supercapacitors (ESs). For MWCNT applications, which depend on electrical conductivity, it is challenging to achieve dispersion and EPD of pristine MWCNT and avoid defects due to chemical treatment or functionalization. An important finding was the possibility of efficient dispersion and controlled EPD of MWCNT using calconcarboxylic acid (CCA). Moreover, the use of CCA allowed efficient dispersion of MnO(2) in concentrated suspensions and EPD of MnO(2) films. The comparison of the experimental data for chromotrope FB (CFB) and CCA and chemical structures of the molecules provided insight into the mechanism of CCA adsorption on MnO(2). The fabrication of stable suspensions of MnO(2) nanoparticles containing MWCNT, and controlled codeposition of both materials is a crucial aspect in the EPD of composites. The new approach was based on the use of CCA as a charging and dispersing agent for EPD of MnO(2) nanoparticles and MWCNT. The deposition yield measurements at various experimental conditions and Fourier transform infrared spectroscopy data, coupled with results of electron microscopy, thermogravimetric, and differential thermal analysis provided evidence of the formation of MnO(2)-MWCNT composites. The electrochemical testing results and impedance spectroscopy data showed good capacitive behavior of the composite films and the beneficial effect of MWCNTs.
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Li, Xue; Shi, Feng; Gong, Liping; Hang, Baojian; Li, Daoyuan; Chi, Lianli
2017-01-01
Colla corii asini (CCA) is a protein-based traditional Chinese medicine made from donkey skins. Because it has the ability to nourish blood, its demand is increasing rapidly. The shortage of donkey skins increases the risk of the adulteration of CCA products with other animal skins. To ensure the drug efficacy and safety of CCA products, a proteomics technique was applied to reveal proteins in the skins of donkey, horse, cattle, and pig. Species-specific peptides for each animal species were predicted using bioinformatics, and their presence in the skins and gelatin samples was examined by nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS). One unique marker peptide for each animal species was selected to develop an LC-MS/MS multiple reaction monitoring method. The capability of this method to identify donkey, horse, cattle, and pig materials was demonstrated by analyzing in-house-made donkey gelatins containing different amounts of other animal skins and commercial CCA products. The adulteration of non-donkey species could be sensitively detected at a low level of 0.5%. Hybrid animals, such as mules and hinnies, were also differentiated from donkeys. We provide a practical tool for the quality control of CCA products. The strategy can also be used to study other important traditional Chinese medicines which contain animal proteins.
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A Los1p-independent pathway for nuclear export of intronless tRNAs in Saccharomycescerevisiae.
Feng, Wenqin; Hopper, Anita K
2002-04-16
Los1p, the Saccharomyces cerevisiae exportin-t homologue, binds tRNA and functions in pre-tRNA splicing and export of mature tRNA from the nucleus to the cytosol. Because LOS1 is unessential in yeast, other pathways for tRNA nuclear export must exist. We report that Cca1p, which adds nucleotides C, C, and A to the 3' end of tRNAs, is a multicopy suppressor of the defect in tRNA nuclear export caused by los1 null mutations. Mes1p, methionyl-tRNA synthetase, also suppresses the defect in nuclear export of tRNA(Met) in los1 cells. Thus, Cca1p and Mes1p seem to function in a Los1p-independent tRNA nuclear export pathway. Heterokaryon analysis indicates that Cca1p is a nucleus/cytosol-shuttling protein, providing the potential for Cca1p to function as an exporter or an adapter in this tRNA nuclear export pathway. In yeast, most mutations that affect tRNA nuclear export also cause defects in pre-tRNA splicing leading to tight coupling of the splicing and export processes. In contrast, we show that overexpressed Cca1p corrects the nuclear export, but not the pre-tRNA-splicing defects of los1Kan(r) cells, thereby uncoupling pre-tRNA splicing and tRNA nuclear export.
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Agyei, Justice O; Alvarez, Cynthia; Iqbal, Azher; Fanous, Andrew A; Siddiqui, Adnan H
2018-06-01
A rare complication following tracheotomy is common carotid artery (CCA) pseudoaneurysm. Treatment modalities for CCA pseudoaneurysm include surgical repair and single-artery balloon-covered stent graft technique. We describe successful treatment of tracheotomy-related CCA pseudoaneurysm with the "kissing balloon" expandable stent graft technique. We successfully implemented the kissing balloon expandable stent graft technique for treatment of a large, narrow-necked, bilobed CCA pseudoaneurysm that arose owing to a tracheotomy complication. The pseudoaneurysm was detected while performing a diagnostic angiogram of the aortic arch and surrounding vessels. The stent was deployed while the 2 balloons were introduced in a kissing manner such that they faced one another to avoid occlusion of either branch of the innominate artery coming into contact; 1 balloon was inflated at the origin of the right subclavian artery, and the other was inflated at the right innominate artery simultaneously. The pseudoaneurysm was successfully contained; normal blood flow was restored in the CCA. The balloons were deflated and withdrawn. The patient remained neurologically intact after the procedure. The kissing balloon technique is a safe and effective alternative to surgical repair, as it prevents morbidities associated with the surgical procedure. Also, this technique decreases the risk of major side-branch occlusion associated with the single-artery balloon-covered stent graft technique. Copyright © 2018 Elsevier Inc. All rights reserved.
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Segregation of colloidal swimmers by their activity
NASA Astrophysics Data System (ADS)
Ferrari, Melissa; Youssef, Mena; Driscoll, Michelle; Sacanna, Stefano; Pine, David; Chaikin, Paul
We study a system of micron sized self-propelled colloidal swimmers whose activity can be switched on or off with the flick of a light switch. We have designed a system where an external LED source reflects light off of an array with hundreds of thousands of independently controlled tiny mirrors, through an optical microscope, and onto the plane of the swimmers. By exposing a collection of particles to a spatial or dynamic light field, we have the ability to control the speed of a particle based on its position, and therefore the density of the collection of particles in space. Theoreticians in the field have been building a framework that describes systems which are out-of-equilibrium and we will show how our system can be useful tool in mapping these theories to experiment. Center for Bio-inspired Energy Science.
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Kim, Youngjo; Lam, Nguyen Dinh; Kim, Kangho; Kim, Sangin; Rotermund, Fabian; Lim, Hanjo; Lee, Jaejin
2012-07-01
Single-junction GaAs solar cell structures were grown by low-pressure MOCVD on GaAs (100) substrates. Micro-rod arrays with diameters of 2 microm, 5 microm, and 10 microm were fabricated on the surfaces of the GaAs solar cells via photolithography and wet chemical etching. The patterned surfaces were coated with Au nanoparticles using an Au colloidal solution. Characteristics of the GaAs solar cells with and without the micro-rod arrays and Au nanoparticles were investigated. The short-circuit current density of the GaAs solar cell with 2 microm rod arrays and Au nanoparticles increased up to 34.9% compared to that of the reference cell without micro-rod arrays and Au nanoparticles. The conversion efficiency of the GaAs solar cell that was coated with Au nanoparticles on the patterned surface with micro-rod arrays can be improved from 14.1% to 19.9% under 1 sun AM 1.5G illumination. These results show that micro-rod arrays and Au nanoparticle coating can be applied together in surface patterning to achieve a novel cost-effective anti-reflection technology.
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WASTE REDUCTION PRACTICES AT TWO CHROMATED COPPER ARSENATE WOOD-TREATING PLANTS
Two chromated copper arsenate (CCA) wood-treating plants were assessed for their waste reduction practices. The objectives of this study were to estimate the amount of hazardous wastes that a well-designed and well-main- tained CCA treatment facility would generate and to iden- t...
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Concerns have been raised regarding the safety of young children contacting arsenic and chromium residues while playing on and around Chromated Copper Arsenate (CCA) treated wood playground structures and decks. Although CCA registrants voluntarily canceled treated wood for resi...
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BIOAVAILABILITY OF ARSENIC, CHROMIUM, AND COPPER FROM CCA CONTAMINATED SOILS AND DUSTS
It is estimated that 70% of single family homes have pressure-treated wood decks or porches and 14% of playground equipment uses pressure-treated wood. This popular form of wood contains chromated copper arsenate (CCA), which is an antimicrobial pesticide and is currently underg...
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BIOAVAILABILITY OF ARSENIC, CHROMIUM, AND COPPER FOR CCA CONTAMINATED SOILS AND DUST
It is estimated that 70% of single family homes have pressure-treated wood decks or porches and 14% of playground equipment uses pressure-treated wood. This popular form of wood contains chromated copper arsenate (CCA), which is an antimicrobial pesticide and is currently underg...
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Zhang, Peirui; Duan, Yueqiang; Zhang, Dexi; Zhang, Shaogeng; Li, Zhiwei; Wang, Xiliang; Yang, Penghui
2014-01-01
Type B influenza virus is a major epidemic strain responsible for considerable mortality and morbidity. A colloidal gold immunochromatographic strip for the rapid detection of human influenza B virus was developed. This test is based on membrane chromatography and uses colloidal gold conjugated with influenza B virus anti-NP monoclonal antibody as the tracer. The assembled test strip was housed in a plastic case. The colloid gold strip (CGS) specifically detected all influenza B viruses tested and did not react with other respiratory viruses. Compared with SYBR Green real-time PCR, the sensitivity and specificity of the CGS test was 89.76% and 99.56%, respectively, and the consistency ratio between CGS and real-time PCR was 96.06% in detecting influenza B virus in 710 nasopharyngeal swabs from patients with influenza-like illness in the hospital. The CGS array developed in this study enabled typing of influenza B viruses in human clinical specimens. Thus, together with the advantages of rapid detection and easy operation without requiring specialized personnel and equipment, this technique is a convenient and relatively inexpensive diagnostic tool for large-scale screening of clinical samples.
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Folding dynamics of linear emulsion polymers into 3D architectures
NASA Astrophysics Data System (ADS)
McMullen, Angus; Bargteil, Dylan; Brujic, Jasna
Colloidal polymers have been limited to inflexible, solid colloids. Here we show that the fluidity of emulsion droplets allows for the self-assembly of flexible droplet chains, which can subsequently be folded into 3D structures via secondary interactions. We achieve this using DNA-guided interactions, to initially form the chain, and then program its folding pathways. When two emulsion droplets labeled with complementary DNA meet, the balance of hybridization energy and droplet deformation yields an equilibrium patch size. Therefore, the concentration of DNA on the surface determines the number of droplet-droplet bonds in the assembly. We find that 96 % of bound droplets successfully self-assemble into chains. Droplet binding is a stochastic process, following a Poisson distribution of lengths. Since the fluid droplets can rearrange, we compare the dynamics of emulsion chains to that of polymers. We also trigger secondary interactions along the chain, causing the formation of specific loops or compact clusters. This approach will allow us to fold our emulsion polymers into a wide array of soft structures, giving us a powerful biomimetic colloidal system to investigate protein folding on the mesoscopic scale. This work was supported by the NSF MRSEC Program (DMR-0820341).
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Methods of affecting nitrogen assimilation in plants
Coruzzi, Gloria; Gutierrez, Rodrigo A.; Nero, Damion C.
2016-10-11
Provided herein are compositions and methods for producing transgenic plants. In specific embodiments, transgenic plants comprise a construct comprising a polynucleotide encoding CCA1, GLK1 or bZIP1, operably linked to a plant-specific promote, wherein the CCA1, GLK1 or bZIP1 is ectopically overexpressed in the transgenic plants, and wherein the promoter is optionally a constitutive or inducible promoter. In other embodiments, transgenic plants in which express a lower level of CCA1, GLK1 or bZIP1 are provided. Also provided herein are commercial products (e.g., pulp, paper, paper products, or lumber) derived from the transgenic plants (e.g., transgenic trees) produced using the methods provided herein.
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Evaluation of Genomic Instability in the Abnormal Prostate
2007-12-01
Mehrotra, J., Varde, S., Wang, H., Chiu, H., Vargo, J., Gray , K., Nagle, R.B., Neri, J.R., Mazumder, A. (2007) Prostate 68, 152-60. Appendix A...GSTP-1 Reverse 5’-GCC CCA ATA CTA AAT CAC GAC G-3’ GSTP-1 Probe 5’-6-FAM-CGG TCG ACG TTC GGG GTG TAG CG-6-TAMSp-3’ RassF1A Forward 5’-GCG TTG AAG...GAA CCA AAA CGC TCC CCA T-3’ APC Reverse 5’-TTA TAT GTC GGT TAC GTG CGT TTA TAT-3’ APC Probe 5’-6-FAM-CCC GTC GAA AAC CCG CCG ATT A-6-TAMSp-3
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Surface-enhanced Raman scattering from metal and transition metal nano-caped arrays
NASA Astrophysics Data System (ADS)
Sun, Huanhuan; Gao, Renxian; Zhu, Aonan; Hua, Zhong; Chen, Lei; Wang, Yaxin; Zhang, Yongjun
2018-03-01
The metal and transition metal cap-shaped arrays on polystyrene colloidal particle (PSCP) templates were fabricated to study the surface-enhanced Raman scattering (SERS) effect. We obtained the Ag and Fe complex film by a co-sputtering deposition method. The size of the deposited Fe particle was changed by the sputtering power. We also study the SERS enhancement mechanism by decorating the PATP probe molecule on the different films. The SERS signals increased firstly, and then decreased as the size of Fe particles grows gradually. The finite-difference time domain (FDTD) simulation and experimental Raman results manifest that SERS enhancement was mainly attributed to surface plasma resonance (SPR) between Ag and Ag nanoparticles. The SERS signals of PATP molecule were enhanced to reach a lowest detectable concentration of 10-8 mol/L. The research demonstrates that the SERS substrates with Ag-Fe cap-shaped arrays have a high sensitivity.
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An overview of inverted colloidal crystal systems for tissue engineering.
João, Carlos Filipe C; Vasconcelos, Joana Marta; Silva, Jorge Carvalho; Borges, João Paulo
2014-10-01
Scaffolding is at the heart of tissue engineering but the number of techniques available for turning biomaterials into scaffolds displaying the features required for a tissue engineering application is somewhat limited. Inverted colloidal crystals (ICCs) are inverse replicas of an ordered array of monodisperse colloidal particles, which organize themselves in packed long-range crystals. The literature on ICC systems has grown enormously in the past 20 years, driven by the need to find organized macroporous structures. Although replicating the structure of packed colloidal crystals (CCs) into solid structures has produced a wide range of advanced materials (e.g., photonic crystals, catalysts, and membranes) only in recent years have ICCs been evaluated as devices for medical/pharmaceutical and tissue engineering applications. The geometry, size, pore density, and interconnectivity are features of the scaffold that strongly affect the cell environment with consequences on cell adhesion, proliferation, and differentiation. ICC scaffolds are highly geometrically ordered structures with increased porosity and connectivity, which enhances oxygen and nutrient diffusion, providing optimum cellular development. In comparison to other types of scaffolds, ICCs have three major unique features: the isotropic three-dimensional environment, comprising highly uniform and size-controllable pores, and the presence of windows connecting adjacent pores. Thus far, this is the only technique that guarantees these features with a long-range order, between a few nanometers and thousands of micrometers. In this review, we present the current development status of ICC scaffolds for tissue engineering applications.
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Finishability of CCA pressure-treated wood
Alan Ross; Richard Carlson; William Feist; Steven Bussjaeger
2000-01-01
Thus, a need arose for the development of surface finishes for CCA-treated wood that could address the special requirements of this substrate and provide protection against the ravages of water, sunlight, mildew, and other aspects of weathering and wear. Initially, this need was not addressed, most wood preserving companies had little expertise in surface finishes and...
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EPA conducted a study to evaluate the effect of coatings on dislodgeable arsenic, chromium, and copper residues on the surfaces of chromated copper arsenate (CAA) treated wood. Dislodgeable CCA, determined by wipe sampling the wood surfaces, was the primary evaluation criterion f...
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The role of moisture content in above-ground leaching
Stan Lebow; Patricia Lebow
2007-01-01
This paper reviews previous reports on the moisture content of wood exposed above ground and compares those values to moisture contents obtained using simulated rainfall and immersion methods. Laboratory leaching trials with CCA-treated specimens were also conducted and the results compared to published values for leaching of CCA-treated specimens exposed above ground...
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Chemical yields from low-temperature pyrolysis of CCA-treated wood
Qirong Fu; Dimitris Argyropolous; Lucian Lucia; David Tilotta; Stan Lebow
2009-01-01
Low-temperature pyrolysis offers a feasible option for wood-waste management and the recovery of a variety of useful chemicals. The effect of chromated copper arsenate (CCA) wood preservative on the yield and composition of various pyrolysis products was investigated in the present research. A novel quantitative 31P nuclear magnetic resonance (...
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The Constant Comparative Analysis Method Outside of Grounded Theory
ERIC Educational Resources Information Center
Fram, Sheila M.
2013-01-01
This commentary addresses the gap in the literature regarding discussion of the legitimate use of Constant Comparative Analysis Method (CCA) outside of Grounded Theory. The purpose is to show the strength of using CCA to maintain the emic perspective and how theoretical frameworks can maintain the etic perspective throughout the analysis. My…
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Correlational Neural Networks.
Chandar, Sarath; Khapra, Mitesh M; Larochelle, Hugo; Ravindran, Balaraman
2016-02-01
Common representation learning (CRL), wherein different descriptions (or views) of the data are embedded in a common subspace, has been receiving a lot of attention recently. Two popular paradigms here are canonical correlation analysis (CCA)-based approaches and autoencoder (AE)-based approaches. CCA-based approaches learn a joint representation by maximizing correlation of the views when projected to the common subspace. AE-based methods learn a common representation by minimizing the error of reconstructing the two views. Each of these approaches has its own advantages and disadvantages. For example, while CCA-based approaches outperform AE-based approaches for the task of transfer learning, they are not as scalable as the latter. In this work, we propose an AE-based approach, correlational neural network (CorrNet), that explicitly maximizes correlation among the views when projected to the common subspace. Through a series of experiments, we demonstrate that the proposed CorrNet is better than AE and CCA with respect to its ability to learn correlated common representations. We employ CorrNet for several cross-language tasks and show that the representations learned using it perform better than the ones learned using other state-of-the-art approaches.
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Doropoulos, Christopher; Ward, Selina; Diaz-Pulido, Guillermo; Hoegh-Guldberg, Ove; Mumby, Peter J
2012-04-01
Ecology Letters (2012) 15: 338-346 ABSTRACT: Successful recruitment in shallow reef ecosystems often involves specific cues that connect planktonic invertebrate larvae with particular crustose coralline algae (CCA) during settlement. While ocean acidification (OA) can reduce larval settlement and the abundance of CCA, the impact of OA on the interactions between planktonic larvae and their preferred settlement substrate are unknown. Here, we demonstrate that CO2 concentrations (800 and 1300 μatm) predicted to occur by the end of this century significantly reduce coral (Acropora millepora) settlement and CCA cover by ≥ 45%. The CCA important for inducing coral settlement (Titanoderma spp., Hydrolithon spp.) were the most deleteriously affected by OA. Surprisingly, the only preferred settlement substrate (Titanoderma) in the experimental controls was avoided by coral larvae as pCO2 increased, and other substrata selected. Our results suggest OA may reduce coral population recovery by reducing coral settlement rates, disrupting larval settlement behaviour, and reducing the availability of the most desirable coralline algal species for successful coral recruitment. © 2012 Blackwell Publishing Ltd/CNRS.
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Cluster compression algorithm: A joint clustering/data compression concept
NASA Technical Reports Server (NTRS)
Hilbert, E. E.
1977-01-01
The Cluster Compression Algorithm (CCA), which was developed to reduce costs associated with transmitting, storing, distributing, and interpreting LANDSAT multispectral image data is described. The CCA is a preprocessing algorithm that uses feature extraction and data compression to more efficiently represent the information in the image data. The format of the preprocessed data enables simply a look-up table decoding and direct use of the extracted features to reduce user computation for either image reconstruction, or computer interpretation of the image data. Basically, the CCA uses spatially local clustering to extract features from the image data to describe spectral characteristics of the data set. In addition, the features may be used to form a sequence of scalar numbers that define each picture element in terms of the cluster features. This sequence, called the feature map, is then efficiently represented by using source encoding concepts. Various forms of the CCA are defined and experimental results are presented to show trade-offs and characteristics of the various implementations. Examples are provided that demonstrate the application of the cluster compression concept to multi-spectral images from LANDSAT and other sources.
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2D photonic crystal complete band gap search using a cyclic cellular automaton refination
NASA Astrophysics Data System (ADS)
González-García, R.; Castañón, G.; Hernández-Figueroa, H. E.
2014-11-01
We present a refination method based on a cyclic cellular automaton (CCA) that simulates a crystallization-like process, aided with a heuristic evolutionary method called differential evolution (DE) used to perform an ordered search of full photonic band gaps (FPBGs) in a 2D photonic crystal (PC). The solution is proposed as a combinatorial optimization of the elements in a binary array. These elements represent the existence or absence of a dielectric material surrounded by air, thus representing a general geometry whose search space is defined by the number of elements in such array. A block-iterative frequency-domain method was used to compute the FPBGs on a PC, when present. DE has proved to be useful in combinatorial problems and we also present an implementation feature that takes advantage of the periodic nature of PCs to enhance the convergence of this algorithm. Finally, we used this methodology to find a PC structure with a 19% bandgap-to-midgap ratio without requiring previous information of suboptimal configurations and we made a statistical study of how it is affected by disorder in the borders of the structure compared with a previous work that uses a genetic algorithm.
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Chorioamnionitis in the Development of Cerebral Palsy: A Meta-analysis and Systematic Review
Ma, Lin; Luo, Kehuan; Bajaj, Monika; Chawla, Sanjay; Natarajan, Girija; Hagberg, Henrik; Tan, Sidhartha
2017-01-01
CONTEXT: Chorioamnionitis (CA) has often been linked etiologically to cerebral palsy (CP). OBJECTIVES: To differentiate association from risk of CA in the development of CP. DATA SOURCES: PubMed, Cochrane Library, Embase, and bibliographies of original studies were searched by using the keywords (chorioamnionitis) AND ((cerebral palsy) OR brain). STUDY SELECTION: Included studies had to have: (1) controls, (2) criteria for diagnoses, and (3) neurologic follow-up. Studies were categorized based on: (1) finding incidence of CP in a CA population, or risk of CP; and (2) incidence of CA in CP or association with CP. DATA EXTRACTION: Two reviewers independently verified study inclusion and extracted data. RESULTS: Seventeen studies (125 256 CA patients and 5 994 722 controls) reported CP in CA. There was significantly increased CP inpreterm histologic chorioamnionitis (HCA; risk ratio [RR] = 1.34, P < .01), but not in clinical CA (CCA). Twenty-two studies (2513 CP patients and 8135 controls) reported CA in CP. There was increased CCA (RR = 1.43, P < .01), but no increase in HCA in preterm CP. Increased HCA was found (RR = 4.26, P < .05), as well as CCA in term/near-term CP (RR = 3.06, P < .01). CONCLUSIONS: The evidence for a causal or associative role of CA in CP is weak. Preterm HCA may be a risk factor for CP, whereas CCA is not. An association with term and preterm CP was found for CCA, but only with term CP for HCA. PMID:28814548
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Cancer biomarker discovery for cholangiocarcinoma: the high-throughput approaches
Silsirivanit, Atit; Sawanyawisuth, Kanlayanee; Riggins, Gregory J.; Wongkham, Chaisiri
2015-01-01
Cholangiocarcinoma (CCA) is difficult to diagnose at an early stage and most tumors are detected at late stage where surgery or other therapy is ineffective. Many advanced techniques are applied to diagnose CCA; however, most are expensive and have varying degrees of accuracy. A less invasive and simpler procedure such as serum markers would be of substantial clinical benefit for diagnosis, monitoring, and predicting outcome for CCA patients. Recent advances in “Omics” technologies offer remarkable opportunities for establishment of biomarker-related to diseases. In this review, the potential biomarkers obtained from proteomics and glycomic studies are evaluated. Several protein markers were discovered from patient specimen, using two dimensional-differential gel electrophoresis couple with liquid chromatography tandem mass spectrometry (2D-DIGE/LC-MS-MS), matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS), surface enhanced laser desorption/ionization (SELDI)-TOF-MS and capillary electrophoresis (CE)-MS, etc. Newly reported CCA-associated glycobiomarkers were identified using lectin-assisted, monoclonal antibody-assisted or specific-target strategies. The combination between carbohydrate binding-lectin and core protein-binding mAb significantly increased the values for detection of the glyco-biomarkers for CCA. Searching for specific and sensitive molecular markers to be used for population screening is worth being evaluated. This could lead to earlier diagnosis and improve outcome. Further investigation of those biomarker functions is also of value in order to better understand the tumor biology and use them as targets for future therapeutic agents. PMID:24616382
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Song, Yeon Hui; Kim, Chan; Kim, Jungsoo; Seo, Sol-Ji; Jeong, Young-Il; Kang, Dae Hwan
2017-01-01
Purpose The aim of this study was to fabricate a vorinostat (Zolinza™)-eluting nanofiber membrane-coated gastrointestinal (GI) stent and to study its antitumor activity against cholangiocarcinoma (CCA) cells in vitro and in vivo. Methods Vorinostat and poly(DL-lactide-co-glycolide) dissolved in an organic solvent was sprayed onto a GI stent to make a nanofiber-coated stent using an electro-spinning machine. Intact vorinostat and vorinostat released from nanofibers was used to assess anticancer activity in vitro against various CCA cells. The antitumor activity of the vorinostat-eluting nanofiber membrane-coated stent was evaluated using HuCC-T1 bearing mice. Results A vorinostat-incorporated polymer nanofiber membrane was formed on the surface of the GI stent. Vorinostat was continuously released from the nanofiber membrane over 10 days, and its release rate was higher in cell culture media than in phosphate-buffered saline. Released vorinostat showed similar anticancer activity against various CCA cells in vitro compared to that of vorinostat. Like vorinostat, vorinostat released from nanofibers induced acetylation of histone H4 and inhibited histone deacetylases 1⋅3⋅4/5/7 expression in vitro and in vivo. Furthermore, vorinostat nanofibers showed a higher tumor growth inhibition rate in HuCC-T1 bearing mice than vorinostat injections. Conclusion Vorinostat-eluting nanofiber membranes showed significant antitumor activity against CCA cells in vitro and in vivo. We suggest the vorinostat nanofiber-coated stent may be a promising candidate for CCA treatment. PMID:29089762
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Kure, Christina E; Rosenfeldt, Franklin L; Scholey, Andrew B; Pipingas, Andrew; Kaye, David M; Bergin, Peter J; Croft, Kevin D; Wesnes, Keith A; Myers, Stephen P; Stough, Con
2016-07-01
The mechanisms for cognitive impairment in heart failure (HF) are unclear. We investigated the relative contributions of cerebral blood flow velocity (BFV), oxidative stress, and inflammation to HF-associated cognitive impairment. Thirty-six HF patients (≥60 years) and 40 healthy controls (68 ± 7 vs 67 ± 5 years, P > .05; 69% vs 50% male, P > .05) completed the Cognitive Drug Research computerized assessment battery and Stroop tasks. Common carotid (CCA) and middle cerebral arterial BFV were obtained by transcranial Doppler. Blood samples were collected for oxidant (diacron-reactive oxygen metabolites; F2-isoprostanes), antioxidant (coenzyme Q10; CoQ10), and inflammatory markers (high-sensitivity C-reactive protein). Compared with controls, patients exhibited impaired attention (Cognitive Drug Research's Power of Attention domain, congruent Stroop) and executive function (incongruent Stroop). Multiple regression modeling showed that CCA-BFV and CoQ10 but not group predicted performance on attention and executive function. Additionally, in HF patients, CCA-BFV and CoQ10 (β = -0.34 vs β = -0.35) were significant predictors of attention, and CCA-BFV (β = -0.34) was a predictor of executive function. Power of Attention and executive function is impaired in older HF patients, and reduced CCA-BFV and CoQ10 are associated with worse cognition. Interventions addressing these mechanisms may improve cognition in older HF patients. Copyright © 2016 Elsevier Inc. All rights reserved.
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Engineering of a green-light inducible gene expression system in Synechocystis sp. PCC6803.
Abe, Koichi; Miyake, Kotone; Nakamura, Mayumi; Kojima, Katsuhiro; Ferri, Stefano; Ikebukuro, Kazunori; Sode, Koji
2014-03-01
In order to construct a green-light-regulated gene expression system for cyanobacteria, we characterized a green-light sensing system derived from Synechocystis sp. PCC6803, consisting of the green-light sensing histidine kinase CcaS, the cognate response regulator CcaR, and the promoter of cpcG2 (PcpcG 2 ). CcaS and CcaR act as a genetic controller and activate gene expression from PcpcG 2 with green-light illumination. The green-light induction level of the native PcpcG 2 was investigated using GFPuv as a reporter gene inserted in a broad-host-range vector. A clear induction of protein expression from native PcpcG 2 under green-light illumination was observed; however, the expression level was very low compared with Ptrc , which was reported to act as a constitutive promoter in cyanobacteria. Therefore, a Shine-Dalgarno-like sequence derived from the cpcB gene was inserted in the 5' untranslated region of the cpcG2 gene, and the expression level of CcaR was increased. Thus, constructed engineered green-light sensing system resulted in about 40-fold higher protein expression than with the wild-type promoter with a high ON/OFF ratio under green-light illumination. The engineered green-light gene expression system would be a useful genetic tool for controlling gene expression in the emergent cyanobacterial bioprocesses. © 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
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Modified technique for common carotid artery transposition in standing horses.
Tapio, Heidi; Argüelles, David; Gracia-Calvo, Luis A; Raekallio, Marja
2017-01-01
To describe a modified technique for permanent translocation of the common carotid artery (CCA) to a subcutaneous position in standing horses. Experimental study. Healthy adult Standardbred and Warmblood horses (n = 8). Surgery was performed with the horses standing under sedation and with local anesthesia. A combination of previously described techniques was used modifying the approach and closure of the incision. The right CCA was approached through a linear skin incision dorsal and parallel to the jugular vein and through the brachiocephalicus and omohyoideus muscles. The artery was dissected free of its sheath and elevated to the skin incision with Penrose drains. The brachiocephalicus muscle was sutured in two layers underneath the artery leaving it in a subcutaneous position. The horses were allowed to heal for 3 weeks prior to catheterization of the artery. The transposed CCA was successfully used for repeated catheterization in six of eight horses for a period of 10 weeks. None of the horses had intraoperative complications. Two horses developed mild peri-incisional edema that resolved spontaneously. Right-sided laryngeal hemiplegia was observed endoscopically in two horses postoperatively. Two horses developed complications (surgical site infection and excessive periarterial fibrosis) that compromised the patency of the CCA and precluded catheterization. Permanent translocation of the CCA in standing horses was successful in six out of eight horses. Upper airway endoscopy postoperatively may be warranted as laryngeal hemiplegia may ensue. © 2016 The American College of Veterinary Surgeons.
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A Los1p-independent pathway for nuclear export of intronless tRNAs in Saccharomyces cerevisiae
Feng, Wenqin; Hopper, Anita K.
2002-01-01
Los1p, the Saccharomyces cerevisiae exportin-t homologue, binds tRNA and functions in pre-tRNA splicing and export of mature tRNA from the nucleus to the cytosol. Because LOS1 is unessential in yeast, other pathways for tRNA nuclear export must exist. We report that Cca1p, which adds nucleotides C, C, and A to the 3′ end of tRNAs, is a multicopy suppressor of the defect in tRNA nuclear export caused by los1 null mutations. Mes1p, methionyl-tRNA synthetase, also suppresses the defect in nuclear export of tRNAMet in los1 cells. Thus, Cca1p and Mes1p seem to function in a Los1p-independent tRNA nuclear export pathway. Heterokaryon analysis indicates that Cca1p is a nucleus/cytosol-shuttling protein, providing the potential for Cca1p to function as an exporter or an adapter in this tRNA nuclear export pathway. In yeast, most mutations that affect tRNA nuclear export also cause defects in pre-tRNA splicing leading to tight coupling of the splicing and export processes. In contrast, we show that overexpressed Cca1p corrects the nuclear export, but not the pre-tRNA-splicing defects of los1∷Kanr cells, thereby uncoupling pre-tRNA splicing and tRNA nuclear export. PMID:11959996
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Wang, Hao; Wang, Qining; Teat, Simon J.; ...
2017-02-15
Porous metal-organic framework (MOF) materials with high thermal and water stability are desirable for various adsorption based applications. Early transition metal based MOFs such as those built on zirconium metal have been well recognized for their excellent stability toward heat and/or moisture. However, the difficulty growing large single crystals makes their structural characterization challenging. Herein we report a porous Zr-MOF, [Zr 6O 4(OH) 4(cca) 6] (Zr-cca), which is assembled from zirconium and 4-carboxycinnamic acid (H 2cca) under solvothermal conditions. Single crystal X-ray diffraction analysis reveals that the structure of Zr-cca is isoreticular to the prototype zirconium based MOF, UiO-66. Zr-ccamore » shows permanent porosity upon removal of solvent molecules initially residing inside the pores, with a BET surface area of 1178 m 2/g. As expected, it exhibits good thermal stability (stable up to 400 °C) and high resistance to acidity over a wide pH range. Evaluation of its gas adsorption performance on various hydrocarbons and fluorocarbons indicates that it preferentially adsorbs C 3 and C 4 hydrocarbons over C 2 analogues. At 30°C Zr-cca takes up more than 50 wt % of perfluorohexane and the adsorption-desorption process is fully recyclable. We have compared this material with UiO-66 and studied the underlying reasons for the difference in their adsorption performance toward perfluorohexane.« less
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Kim, Ji-Hoon; Yu, Daeung; Eom, Sung-Hwan; Kim, Song-Hee; Oh, Junghwan; Jung, Won-Kyo; Kim, Young-Mog
2017-06-08
The object of this study was to discover an alternative therapeutic agent with fewer side effects against acne vulgaris, one of the most common skin diseases. Acne vulgaris is often associated with acne-related bacteria such as Propionibacterium acnes , Staphylococcus epidermidis , Staphylococcus aureus , and Pseudomonas aeruginosa . Some of these bacteria exhibit a resistance against commercial antibiotics that have been used in the treatment of acne vulgaris (tetracycline, erythromycin, and lincomycin). In the current study, we tested in vitro antibacterial effect of chitosan-phytochemical conjugates on acne-related bacteria. Three chitosan-phytochemical conjugates used in this study exhibited stronger antibacterial activity than that of chitosan (unmodified control). Chitosan-caffeic acid conjugate (CCA) showed the highest antibacterial effect on acne-related bacteria along with minimum inhibitory concentration (MIC; 8 to 256 μg/mL). Additionally, the MIC values of antibiotics against antibiotic-resistant P. acnes and P. aeruginosa strains were dramatically reduced in combination with CCA, suggesting that CCA would restore the antibacterial activity of the antibiotics. The analysis of fractional inhibitory concentration (FIC) indices clearly revealed a synergistic antibacterial effect of CCA with antibiotics. Thus, the median sum of FIC (∑FIC) values against the antibiotic-resistant bacterial strains ranged from 0.375 to 0.533 in the combination mode of CCA and antibiotics. The results of the present study suggested a potential possibility of chitosan-phytochemical conjugates in the control of infections related to acne vulgaris.
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Elmore, M Holly; McGary, Kriston L; Wisecaver, Jennifer H; Slot, Jason C; Geiser, David M; Sink, Stacy; O'Donnell, Kerry; Rokas, Antonis
2015-02-06
Fungi that have the enzymes cyanase and carbonic anhydrase show a limited capacity to detoxify cyanate, a fungicide employed by both plants and humans. Here, we describe a novel two-gene cluster that comprises duplicated cyanase and carbonic anhydrase copies, which we name the CCA gene cluster, trace its evolution across Ascomycetes, and examine the evolutionary dynamics of its spread among lineages of the Fusarium oxysporum species complex (hereafter referred to as the FOSC), a cosmopolitan clade of purportedly clonal vascular wilt plant pathogens. Phylogenetic analysis of fungal cyanase and carbonic anhydrase genes reveals that the CCA gene cluster arose independently at least twice and is now present in three lineages, namely Cochliobolus lunatus, Oidiodendron maius, and the FOSC. Genome-wide surveys within the FOSC indicate that the CCA gene cluster varies in copy number across isolates, is always located on accessory chromosomes, and is absent in FOSC's closest relatives. Phylogenetic reconstruction of the CCA gene cluster in 163 FOSC strains from a wide variety of hosts suggests a recent history of rampant transfers between isolates. We hypothesize that the independent formation of the CCA gene cluster in different fungal lineages and its spread across FOSC strains may be associated with resistance to plant-produced cyanates or to use of cyanate fungicides in agriculture. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
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NASA Technical Reports Server (NTRS)
Ramachandiran, S.; Takezawa, D.; Wang, W.; Poovaiah, B. W.
1997-01-01
A novel calcium-binding calcium/calmodulin-dependent protein kinase (CCaMK) with a catalytic domain, calmodulin-binding domain, and a neural visinin-like domain was cloned and characterized from plants [Patil et al., (1995) Proc. Natl. Acad. Sci. USA 92, 4797-4801; Takezawa et al. (1996) J. Biol. Chem. 271, 8126-8132]. The mechanisms of CCaMK activation by calcium and calcium/calmodulin were investigated using various deletion mutants. The use of deletion mutants of CCaMK lacking either one, two, or all three calcium-binding EF hands indicated that all three calcium-binding sites in the visinin-like domain were crucial for the full calcium/calmodulin-dependent kinase activity. As each calcium-binding EF hand was deleted, there was a gradual reduction in calcium/calmodulin-dependent kinase activity from 100 to 4%. Another mutant (amino acids 1-322) which lacks both the visinin-like domain containing three EF hands and the calmodulin-binding domain was constitutively active, indicating the presence of an autoinhibitory domain around the calmodulin-binding domain. By using various synthetic peptides and the constitutively active mutant, we have shown that CCaMK contains an autoinhibitory domain within the residues 322-340 which overlaps its calmodulin-binding domain. Kinetic studies with both ATP and the GS peptide substrate suggest that the autoinhibitory domain of CCaMK interacts only with the peptide substrate binding motif of the catalytic domain, but not with the ATP-binding motif.
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Reversible ratchet effects for vortices in conformal pinning arrays
Reichhardt, Charles; Ray, Dipanjan; Reichhardt, Cynthia Jane Olson
2015-05-04
A conformal transformation of a uniform triangular pinning array produces a structure called a conformal crystal which preserves the sixfold ordering of the original lattice but contains a gradient in the pinning density. Here we use numerical simulations to show that vortices in type-II superconductors driven with an ac drive over gradient pinning arrays produce the most pronounced ratchet effect over a wide range of parameters for a conformal array, while square gradient or random gradient arrays with equivalent pinning densities give reduced ratchet effects. In the conformal array, the larger spacing of the pinning sites in the direction transversemore » to the ac drive permits easy funneling of interstitial vortices for one driving direction, producing the enhanced ratchet effect. In the square array, the transverse spacing between pinning sites is uniform, giving no asymmetry in the funneling of the vortices as the driving direction switches, while in the random array, there are numerous easy-flow channels present for either direction of drive. We find multiple ratchet reversals in the conformal arrays as a function of vortex density and ac amplitude, and correlate the features with a reversal in the vortex ordering, which is greater for motion in the ratchet direction. In conclusion, the enhanced conformal pinning ratchet effect can also be realized for colloidal particles moving over a conformal array, indicating the general usefulness of conformal structures for controlling the motion of particles.« less
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Illuminati, Giulio; Pizzardi, Giulia; Pasqua, Rocco; Frezzotti, Francesca; Palumbo, Piergaspare; Macrina, Francesco; Calio', Francesco
2018-04-01
Tandem stenoses of the internal carotid artery (ICA) and proximal, ipsilateral common carotid artery (CCA) or innominate artery can be treated with a hybrid approach, combining conventional carotid endarterectomy (CEA) and retrograde stenting of the proximal stenosis, through surgical exposure of the carotid bifurcation. The purpose of this study was to evaluate the results of combining eversion CEA with retrograde CCA/innominate artery stenting. From January 2015 to July 2017, 7 patients, 6 men of a mean age of 72 years (range 59-83 years) underwent simultaneous, retrograde stenting of the proximal CCA/innominate artery and an eversion CEA of the ipsilateral ICA, through surgical exposure of the carotid bifurcation, for severe tandem stenoses. The proximal stenosis involved the left proximal CCA in 4 patients, the proximal innominate artery in 2 patients and the right CCA in one patient. The procedure was performed under general anesthesia in a conventional operating room equipped with a mobile C-arm. A covered, balloon expandable stent was deployed over the proximal stenosis via a 6-F sheath directly introduced into the proximal CCA through the obliquely transected carotid bulb. After removing the sheath, debris were flushed through the carotid bulb and eversion CEA completed the procedure. Study endpoints were: postoperative stroke/mortality rate, cardiac mortality and morbidity, peripheral nerve injury, cervical hematoma, overall late survival, freedom from ipsilateral stroke and patency of arterial reconstruction. No postoperative mortality or neurologic morbidity was observed in any patient. Cervical hematomas and peripheral nerve injuries were likewise absent. At a mean follow-up of 18 months, all the patients were alive, free from neurologic events of new onset and free from restenosis. Combined proximal stenting and eversion CEA for tandem lesions seems a valid treatment, with the advantages of eversion CEA over other techniques of carotid bifurcation revascularization. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
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Shendre, Aditi; Irvin, Marguerite R; Aouizerat, Bradley E; Wiener, Howard W; Vazquez, Ana I; Anastos, Kathryn; Lazar, Jason; Liu, Chenglong; Karim, Roksana; Limdi, Nita A; Cohen, Mardge H; Golub, Elizabeth T.; Zhi, Degui; Kaplan, Robert C; Shrestha, Sadeep
2014-01-01
Background Single nucleotide polymorphisms (SNPs) in the Ryanodine receptor 3 (RYR3) gene are associated with common carotid intima media thickness (CCA cIMT) in HIV-infected men. We evaluated SNPs in the RYR3 gene among HIV-infected women participating in Women’s Interagency HIV Study (WIHS). Methods CCA cIMT was measured using B-mode ultrasound and the 838 SNPs in the RYR3 gene region were genotyped using the Illumina HumanOmni2.5-quad beadchip. The CCA cIMT genetic association was assessed using linear regression analyses among 1213 women and also separately among White (n=139), Black (n=720) and Hispanic (n=354) women after adjusting for confounders. A summary measure of pooled association was estimated using a meta-analytic approach by combining the effect estimates from the three races. Haploblocks were inferred using Gabriel’s method and haplotype association analyses were conducted among the three races separately. Results SNP rs62012610 was associated with CCA cIMT among the Hispanics (p=4.41× 10−5), rs11856930 among Whites (p=5.62× 10−4), and rs2572204 among Blacks (p=2.45× 10−3). Meta-analysis revealed several associations of SNPs in the same direction and of similar magnitude, particularly among Blacks and Hispanics. Additionally, several haplotypes within three haploblocks containing SNPs previously related with CCA cIMT were also associated in Whites and Hispanics. Discussion Consistent with previous research among HIV-infected men, SNPs within the RYR3 region were associated with subclinical atherosclerosis among HIV-infected women. Allelic heterogeneity observed across the three races suggests that the contribution of the RYR3 gene to CCA cIMT is complex, and warrants future studies to better understand regional SNP function. PMID:24561552
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NASA Astrophysics Data System (ADS)
Vogel, N.; Cantin, N. E.; Strahl, J.; Kaniewska, P.; Bay, L.; Wild, C.; Uthicke, S.
2016-06-01
Epilithic algal communities play critical ecological roles on coral reefs, but their response to individual and interactive effects of ocean warming (OW) and ocean acidification (OA) is still largely unknown. We investigated growth, photosynthesis and calcification of early epilithic algal community assemblages exposed for 6 months to four temperature profiles (-1.1, ±0.0, +0.9, +1.6 °C) that were crossed with four carbon dioxide partial pressure (pCO2) levels (360, 440, 650, 940 µatm), under flow-through conditions and natural light regimes. Additionally, we compared the cover of heavily calcified crustose coralline algae (CCA) and lightly calcified red algae of the genus Peyssonnelia among treatments. Increase in cover of epilithic communities showed optima under moderately elevated temperatures and present pCO2, while cover strongly decreased under high temperatures and high-pCO2 conditions, particularly due to decreasing cover of CCA. Similarly, community calcification rates were strongly decreased at high pCO2 under both measured temperatures. While final cover of CCA decreased under high temperature and pCO2 (additive negative effects), cover of Peyssonnelia spp. increased at high compared to annual average and moderately elevated temperatures. Thus, cover of Peyssonnelia spp. increased in treatment combinations with less CCA, which was supported by a significant negative correlation between organism groups. The different susceptibility to stressors most likely derived from a different calcification intensity and/or mineral. Notably, growth of the epilithic communities and final cover of CCA were strongly decreased under reduced-pCO2 conditions compared to the present. Thus, CCA may have acclimatized from past to present-day pCO2 conditions, and changes in carbonate chemistry, regardless in which direction, negatively affect them. However, if epilithic organisms cannot further acclimatize to OW and OA, the interacting effects of both factors may change epilithic communities in the future, thereby likely leading to reduced reef stability and recovery.
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Neuronal calcium sensor proteins are direct targets of the insulinotropic agent repaglinide.
Okada, Miki; Takezawa, Daisuke; Tachibanaki, Shuji; Kawamura, Satoru; Tokumitsu, Hiroshi; Kobayashi, Ryoji
2003-01-01
The NCS (neuronal calcium sensor) proteins, including neurocalcins, recoverins and visinin-like proteins are members of a family of Ca2+-sensitive regulators, each with three Ca2+-binding EF-hand motifs. In plants, lily CCaMK [chimaeric Ca2+/CaM (calmodulin)-dependent protein kinase] and its PpCaMK ( Physcomitrella patens CCaMK) homologue are characterized by a visinin-like domain with three EF-hands. In the present study, in an effort to discover NCS antagonists, we screened a total of 43 compounds using Ca2+-dependent drug affinity chromatography and found that the insulinotropic agent repaglinide targets the NCS protein family. Repaglinide was found to bind to NCS proteins, but not to CaM or S100 proteins, in a Ca2+-dependent manner. Furthermore, the drug antagonized the inhibitory action of recoverin in a rhodopsin kinase assay with IC50 values of 400 microM. Moreover, repaglinide tightly bound to the visinin-like domain of CCaMK and PpCaMK in a Ca2+-dependent manner and antagonized the regulatory function of the domain with IC50 values of 55 and 4 microM for CCaMK and PpCaMK respectively. Although both repaglinide and a potent insulin secretagogue, namely glibenclamide, blocked K(ATP) channels with similar potency, glibenclamide had no antagonizing effect on the Ca2+-stimulated CCaMK and PpCaMK autophosphorylation, mediated by their visinin-like domain. In addition, a typical CaM antagonist, trifluoperazine, had no effect on the CCaMK and PpCaMK autophosphorylation. Repaglinide appears to be the first antagonist of NCS proteins and visinin-like domain-bearing enzymes. It may serve as a useful tool for evaluating the physiological functions of the NCS protein family. In addition, since repaglinide selectively targets NCS proteins among the EF-hand Ca2+-binding proteins, it is a potential lead compound for the development of more potent NCS antagonists. PMID:12844348
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Sharma, Prerna; Kaila, Pallavi; Guptasarma, Purnananda
2016-12-01
Diverse unrelated enzymes that adopt the beta/alpha (or TIM) barrel topology display similar arrangements of beta/alpha units placed in a radial eight-fold symmetry around the barrel's axis. The TIM barrel was originally thought to be a single structural domain; however, it is now thought that TIM barrels arose from duplication and fusion of smaller half-barrels consisting of four beta/alpha units. We describe here the design, expression and purification, as well as characterization of folding, activity and stability, of chimeras of two TIM barrel glycosyl hydrolases, made by fusing different half-barrel domains derived from an endoglucanase from Clostridium cellulolyticum, CelCCA and a beta-glucosidase from Pyrococcus furiosus, CelB. We show that after refolding following purification from inclusion bodies, the two half-barrel fusion chimeras (CelCCACelB and CelBCelCCA) display catalytic activity although they assemble into large soluble oligomeric aggregated species containing chains of mixed beta and alpha structure. CelBCelCCA displays hyperthermophile-like structural stability as well as significant stability to chemical denaturation (C m of 2.6 m guanidinium hydrochloride), whereas CelCCACelB displays mesophile-like stability (T m of ~ 71 °C). The endoglucanase activities of both chimeras are an order of magnitude lower than those of CelB or CelCCA, whereas the beta-glucosidase activity of CelBCelCCA is about two orders of magnitude lower than that of CelB. The chimera CelCCACelB shows no beta-glucosidase activity. Our results demonstrate that half-barrel domains from unrelated sources can fold, assemble and function, with scope for improvement. Pyrococcus furiosus beta-glucosidase (CelB, EC: 3.2.1.21). Clostridium cellulolyticum endoglucanase A (CelCCA, EC: 3.2.1.4). © 2016 Federation of European Biochemical Societies.
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Arsenic Speciation of Solvent-Extracted Leachate from New and Weathered CCA-Treated Wood
KHAN, BERNINE I.; SOLO - GABRIELE, HELENA M.; DUBEY, BRAJESH K.; TOWNSEND, TIMOTHY G.; CAI, YONG
2009-01-01
For the past 60 yr, chromate-copper-arsenate (CCA) has been used to pressure-treat millions of cubic meters of wood in the United States for the construction of many outdoor structures. Leaching of arsenic from these structures is a possible health concern as there exists the potential for soil and groundwater contamination. While previous studies have focused on total arsenic concentrations leaching from CCA-treated wood, information pertaining to the speciation of arsenic leached is limited. Since arsenic toxicity is dependent upon speciation, the objective of this study was to identify and quantify arsenic species leaching from new and weathered CCA-treated wood and CCA-treated wood ash. Solvent-extraction experiments were carried out by subjecting the treated wood and the ash to solvents of varying pH values, solvents defined in the EPA’s Synthetic Precipitation Leaching Procedure (SPLP) and Toxicity Characteristic Leaching Procedure (TCLP), rainwater, deionized water, and seawater. The generated leachates were analyzed for inorganic As(III) and As(V) and the organoarsenic species, monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA), using high-performance liquid chromatography followed by hydride generation and atomic fluorescence spectrometry (HPLC–HG-AFS). Only the inorganic species were detected in any of the wood leachates; no organoarsenic species were found. Inorganic As(V) was the major detectable species leaching from both new and weathered wood. The weathered wood leached relatively more overall arsenic and was attributed to increased inorganic As(III) leaching. The greater presence of As(III) in the weathered wood samples as compared to the new wood samples may be due to natural chemical and biological transformations during the weathering process. CCA-treated wood ash leached more arsenic than unburned wood using the SPLP and TCLP, and ash samples leached more inorganic As(III) than the unburned counterparts. Increased leaching was due to higher concentrations of arsenic within the ash and to the conversion of some As(V) to As(III) during combustion. PMID:15461159
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Sun, Kexin; Song, Jing; Liu, Kuo; Fang, Kai; Wang, Ling; Wang, Xueyin; Li, Jing; Tang, Xun; Wu, Yiqun; Qin, Xueying; Wu, Tao; Gao, Pei; Chen, Dafang; Hu, Yonghua
2017-04-01
Carotid intima-media thickness (CIMT) is a good surrogate for atherosclerosis. Hyperhomocysteinemia is an independent risk factor for cardiovascular diseases. We aim to investigate the relationships between homocysteine (Hcy) related biochemical indexes and CIMT, the associations between Hcy related SNPs and CIMT, as well as the potential gene-gene interactions. The present study recruited full siblings (186 eligible families with 424 individuals) with no history of cardiovascular events from a rural area of Beijing. We examined CIMT, intima-media thickness for common carotid artery (CCA-IMT) and carotid bifurcation, tested plasma levels for Hcy, vitamin B6 (VB6), vitamin B12 (VB12) and folic acid (FA), and genotyped 9 SNPs on MTHFR, MTR, MTRR, BHMT, SHMT1, CBS genes. Associations between SNPs and biochemical indexes and CIMT indexes were analyzed using family-based association test analysis. We used multi-level mixed-effects regression model to verify SNP-CIMT associations and to explore the potential gene-gene interactions. VB6, VB12 and FA were negatively correlated with CIMT indexes (p < 0.05). rs2851391 T allele was associated with decreased plasma VB12 levels (p = 0.036). In FABT, CBS rs2851391 was significantly associated with CCA-IMT (p = 0.021) and CIMT (p = 0.019). In multi-level mixed-effects regression model, CBS rs2851391 was positively significantly associated with CCA-IMT (Coef = 0.032, se = 0.009, raw p < 0.001) after Bonferoni correction (corrected α = 0.0056). Gene-gene interactions were found between CBS rs2851391 and BHMT rs10037045 for CCA-IMT (p = 0.011), as well as between CBS rs2851391 and MTR rs1805087 for CCA-IMT (p = 0.007) and CIMT (p = 0.022). Significant associations are found between Hcy metabolism related genetic polymorphisms, biochemical indexes and CIMT indexes. There are complex interactions between genetic polymorphisms for CCA-IMT and CIMT.
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Dana, Paweena; Kariya, Ryusho; Vaeteewoottacharn, Kulthida; Sawanyawisuth, Kanlayanee; Seubwai, Wunchana; Matsuda, Kouki; Okada, Seiji; Wongkham, Sopit
2017-08-07
CD147 is a transmembrane protein that can induce the expression and activity of matrix metalloproteinases (MMPs). Expression of CD147 has been shown to potentiate cell migration, invasion, and metastasis of cancer. In this study, the critical role of CD147 in metastasis was elucidated using CD147-overexpressing cholangiocarcinoma (CCA) cells in vitro and in vivo. The molecular mechanism, demonstrated herein, supported the hypothesis that metastasis increased in CD147-overexpressing cells. Five CD147-overexpressing clones (Ex-CD147) were established from a low CD147-expressing CCA cell line, KKU-055, using lentivirus containing pReceiver-Lenti-CD147. The metastatic capability was determined using the tail vein injection mouse model and an in vitro 3D invasion assay. Liver colonization was assessed using anti-HLA class I immunohistochemistry. Adhesion abilities, cytoskeletal arrangements, MMP activities, the expressions of adhesion molecules, and epithelial-mesenchymal transitional markers were analyzed. All Ex-CD147 clones exhibited a high CD147 expression and high liver colonization in the tail vein-injected mouse model, whereas parental cells lacked this ability. Ex-CD147 clones exhibited metastatic phenotypes (i.e., an increase in F-actin rearrangement) and cell invasion and a decrease in cell adhesion. The molecular mechanisms were shown to be via the induction of MMP-2 activity and enhancement of epithelial-mesenchymal transitions. An increase in mesenchymal markers Slug, vimentin, and N-cadherin, and a decrease in epithelial markers E-cadherin and claudin-1, together with suppression of the adhesion molecule ICAM-1, were observed in the Ex-CD147 clones. Moreover, suppression of CD147 expression using siCD147 in two CCA cell lines with high CD147 expression significantly decreased cell migration and invasion of these CCA cells. These findings emphasize the essential role of CD147 in CCA metastasis and suggest CD147 as a promising target for the effective treatment of CCA.
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Auto-production of biosurfactants reverses the coffee ring effect in a bacterial system
NASA Astrophysics Data System (ADS)
Sempels, Wouter; de Dier, Raf; Mizuno, Hideaki; Hofkens, Johan; Vermant, Jan
2013-04-01
The deposition of material at the edge of evaporating droplets, known as the ‘coffee ring effect’, is caused by a radially outward capillary flow. This phenomenon is common to a wide array of systems including colloidal and bacterial systems. The role of surfactants in counteracting these coffee ring depositions is related to the occurrence of local vortices known as Marangoni eddies. Here we show that these swirling flows are universal, and not only lead to a uniform deposition of colloids but also occur in living bacterial systems. Experiments on Pseudomonas aeruginosa suggest that the auto-production of biosurfactants has an essential role in creating a homogeneous deposition of the bacteria upon drying. Moreover, at biologically relevant conditions, intricate time-dependent flows are observed in addition to the vortex regime, which are also effective in reversing the coffee ring effect at even lower surfactant concentrations.
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Perfect mixing of immiscible macromolecules at fluid interfaces
NASA Astrophysics Data System (ADS)
Sheiko, Sergei S.; Zhou, Jing; Arnold, Jamie; Neugebauer, Dorota; Matyjaszewski, Krzysztof; Tsitsilianis, Constantinos; Tsukruk, Vladimir V.; Carrillo, Jan-Michael Y.; Dobrynin, Andrey V.; Rubinstein, Michael
2013-08-01
The difficulty of mixing chemically incompatible substances—in particular macromolecules and colloidal particles—is a canonical problem limiting advances in fields ranging from health care to materials engineering. Although the self-assembly of chemically different moieties has been demonstrated in coordination complexes, supramolecular structures, and colloidal lattices among other systems, the mechanisms of mixing largely rely on specific interfacing of chemically, physically or geometrically complementary objects. Here, by taking advantage of the steric repulsion between brush-like polymers tethered to surface-active species, we obtained long-range arrays of perfectly mixed macromolecules with a variety of polymer architectures and a wide range of chemistries without the need of encoding specific complementarity. The net repulsion arises from the significant increase in the conformational entropy of the brush-like polymers with increasing distance between adjacent macromolecules at fluid interfaces. This entropic-templating assembly strategy enables long-range patterning of thin films on sub-100 nm length scales.
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Properties of structural panels fabricated from bioremediated CCA-treated wood: pilot scale
Carol A. Clausen; James H. Muehl; Andrzej M. Krzysik
2006-01-01
Particleboard and flakeboard panels were fabricated from remediated CCA-treated southern yellow pine. Treated wood, flaked or comminuted into particles, was remediated in 12-kg batches using oxalic acid extraction, followed by bioleaching with the metal-tolerant bacterium Bacillus licheniformis. Remediation resulted in removal of 80 percent Cu, 71 percent Cr, and 89...
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Robert L. Smith; David Bailey; Delton R. Alderman; Philip A. Araman
2006-01-01
The primary goals of this book chapter are to identify barriers to the reuse of treated lumber, to describe the physical properties of spent chromated copper arsenate (CCA)-treated lumber coming from residential decks and to identify potential products and markets that can use spent treated lumber. The primary focus will be on CCA-treated lumber because it has been the...
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Component Cost Analysis of Large Scale Systems
NASA Technical Reports Server (NTRS)
Skelton, R. E.; Yousuff, A.
1982-01-01
The ideas of cost decomposition is summarized to aid in the determination of the relative cost (or 'price') of each component of a linear dynamic system using quadratic performance criteria. In addition to the insights into system behavior that are afforded by such a component cost analysis CCA, these CCA ideas naturally lead to a theory for cost-equivalent realizations.
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Concerns have been raised regarding the safety of young children who may contact arsenic residues while playing on and around chromated copper arsenate (CCA)-treated wood playsets and decks. Although CCA registrants voluntarily canceled the production of treated wood for residen...
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A new version of code Java for 3D simulation of the CCA model
NASA Astrophysics Data System (ADS)
Zhang, Kebo; Xiong, Hailing; Li, Chao
2016-07-01
In this paper we present a new version of the program of CCA model. In order to benefit from the advantages involved in the latest technologies, we migrated the running environment from JDK1.6 to JDK1.7. And the old program was optimized into a new framework, so promoted extendibility.
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Performance of copper-based wood preservatives in soil bed exposures
Stan T. Lebow; Thomas Nilsson; Jeffrey J. Morrell
Copper-based biocides are widely used to protect wood from biological attack in a variety of environments. Chromated copper arsenate (CCA) is the dominant copper-based preservative for wood protection (J. T. MICKLEWRIGHT, 1989). First developed in India in the 1930s, CCA contains a very effective combination of materials. Copper provides protection against most...
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Child-Centered Approach: How Is It Perceived by Preschool Educators in Mongolia?
ERIC Educational Resources Information Center
Myagmar, Ariuntuya
2010-01-01
This study is an attempt to grasp Mongolian preschool educators' perceptions on child-centered approach (CCA). CCA was externally introduced to Mongolia about 10 years ago as a diametrically different education from that of the socialist period. The study also aims to examine the differences that may exist among teachers in different types of…
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New Approach to Remove Metals from Chromated Copper Arsenate (CCA)-Treated Wood
Todd F. Shupe; Chung Y. Hse; Hui Pan
2012-01-01
Recovery of metals from chromated copper arsenate (CCA)-treated southern pine wood particles was investigated using binary acid solutions consisting of acetic, oxalic, and phosphoric acids in a microwave reactor. Formation of an insoluble copper oxalate complex in the binary solution containing oxalic acid was the major factor for low copper removal. Furthermore, the...
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An investigation into the potential of ionic silver as a wood preservative
Benjamin Dorau; Rachel Arango; Frederick Green
2004-01-01
On December 3 1, 2003, the wood preservation industry, in conjunction with the Environmental Protection Agency, voluntarily phased out the use of chromated copper arsenate (CCA)-treated lumber for residential applications. This ended over 25 years of CCA as the predominant wood preservative in the United States. The first generation of replacement preservatives,...
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Cheng Piao; Todd F. Shupe; Mark Gibson; Chung Y. Hse
2009-01-01
Chromated copper arsenate (CCA) continues to be widely used as a wood preservative for industrial uses in the U.S. Disposal of treated wood is a potential long-term environmental liability. Current practices for disposing of decommissioned preservative-treated wood include landfilling and incineration, which are increasingly impractical due to environmental...
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R.A. Arango; F. Green; K. Hintz; R.B. Miller
2004-01-01
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to...
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Rate of CCA leaching from commercially treated decking.
Stan Lebow; Daniel Foster; Patricia Lebow
2004-01-01
Conflicting reports on levels of arsenic in soil beneath decks treated with chromated copper arsenate (CCA) have raised concerns about arsenic exposure from this type of treated wood. This paper reports on an evaluation of the rate of release of copper, chromium, and arsenic from commercially treated lumber as a function of treatment additive (with or without water...
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Particleboard made from remediated CCA-treated wood : evaluation of panel properties
Carol A. Clausen; S. Nami Kartal; James Muehl
2001-01-01
CCA-treated southern yellow pine (SYP) chips were remediated utilizing acid extraction alone, and using acid extraction followed by bioleaching with the metal-tolerant bacterium Bacillus licheniformis CC01. bCleanedc chips were used to make particleboard (PB) with 10 percent urea-formaldehyde (UF) resin, and the PB samples were evaluated for internal bond (IB), modulus...
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Cholangiocarcinoma: Lessons from Thailand
Sripa, Banchob; Pairojkul, Chawalit
2014-01-01
Purpose of the review To present the background of liver fluke-associated cholangiocarcinoma (CCA) in Thailand focusing on recent epidemiological data and pathogenesis of this bile duct cancer. Recent findings More systematic tumor registration in Thailand nowadays uncovers new high incidence areas that do not confine to only in the northeastern part but also some provinces in the northern Thailand. The link between the liver fluke, Opisthorchis viverrini, and CCA, particularly in the cellular and molecular pathogenesis is more elucidated. Summary Thailand is still the country with highest incidence of CCA in the world. Liver fluke induces chronic inflammation leading to oxidative DNA damage of the infected biliary epithelium and malignant transformation. Eradication of the fluke and identification of high risk population are urgently needed. PMID:18408464
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Electron transport within transparent assemblies of tin-doped indium oxide colloidal nanocrystals
NASA Astrophysics Data System (ADS)
Grisolia, J.; Decorde, N.; Gauvin, M.; Sangeetha, N. M.; Viallet, B.; Ressier, L.
2015-08-01
Stripe-like compact assemblies of tin-doped indium oxide (ITO) colloidal nanocrystals (NCs) are fabricated by stop-and-go convective self-assembly (CSA). Systematic evaluation of the electron transport mechanisms in these systems is carried out by varying the length of carboxylate ligands protecting the NCs: butanoate (C4), octanoate (C8) and oleate (C18). The interparticle edge-to-edge distance L0, along with a number of carbon atoms in the alkyl chain of the coating ligand, are deduced from small-angle x-ray scattering (SAXS) measurements and exhibit a linear relationship with a slope of 0.11 nm per carbon pair unit. Temperature-dependent resistance characteristics are analyzed using several electron transport models: Efros-Shklovskii variable range hopping (ES-VRH), inelastic cotunneling (IC), regular island array and percolation. The analysis indicated that the first two models (ES-VRH and IC) fail to explain the observed behavior, and that only simple activated transport takes place in these systems under the experimental conditions studied (T = 300 K to 77 K). Related transport parameters were then extracted using the regular island array and percolation models. The effective tunneling decay constant βeff of the ligands and the Coulomb charging energy EC are found to be around 5.5 nm-1 and 25 meV, respectively, irrespective of ligand lengths. The theoretical tunneling decay constant β calculated using the percolation model is in the range 9 nm-1. Electromechanical tests on the ITO nanoparticle assemblies indicate that their sensitivities are as high as ˜30 and remain the same regardless of ligand lengths, which is in agreement with the constant effective βeff extracted from regular island array and percolation models.
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NASA Astrophysics Data System (ADS)
Fang, Huajing; Yan, Qingfeng; Geng, Chong; Chan, Ngai Yui; Au, Kit; Yao, Jianjun; Ng, Sheung Mei; Leung, Chi Wah; Li, Qiang; Guo, Dong; Wa Chan, Helen Lai; Dai, Jiyan
2016-01-01
Nano-patterned ferroelectric materials have attracted significant attention as the presence of two or more thermodynamically equivalent switchable polarization states can be employed in many applications such as non-volatile memory. In this work, a simple and effective approach for fabrication of highly ordered poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) nanodot arrays is demonstrated. By using a soft polydimethylsiloxane mold, we successfully transferred the 2D array pattern from the initial monolayer of colloidal polystyrene nanospheres to the imprinted P(VDF-TrFE) films via nanoimprinting. The existence of a preferred orientation of the copolymer chain after nanoimprinting was confirmed by Fourier transform infrared spectra. Local polarization switching behavior was measured by piezoresponse force microscopy, and each nanodot showed well-formed hysteresis curve and butterfly loop with a coercive field of ˜62.5 MV/m. To illustrate the potential application of these ordered P(VDF-TrFE) nanodot arrays, the writing and reading process as non-volatile memory was demonstrated at a relatively low voltage. As such, our results offer a facile and promising route to produce arrays of ferroelectric polymer nanodots with improved piezoelectric functionality.
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Graded nanowell arrays: a fine plasmonic "library" with an adjustable spectral range.
Xue, Peihong; Ye, Shunsheng; Su, Hongyang; Wang, Shuli; Nan, Jingjie; Chen, Xingchi; Ruan, Weidong; Zhang, Junhu; Cui, Zhanchen; Yang, Bai
2017-05-25
We present an effective approach for fabricating graded plasmonic arrays based on ordered micro-/nanostructures with a geometric gradient. Ag nanowell arrays with graded geometric parameters were fabricated and systematically investigated. The order of the graded plasmonic arrays is generated by colloidal lithography, while the geometric gradient is the result of inclined reactive ion etching. The surface plasmon resonance (SPR) peaks were measured at different positions, which move gradually along the Ag nanowell arrays with a geometric gradient. Such micro-/nanostructure arrays with graded and integrated SPR peaks can work as a fine plasmonic "library" (FPL), and the spectral range can be controlled using a "coarse adjustment knob" (lattice constant) and a "fine adjustment knob" (pore diameter). Additionally, the spectral resolution of the FPL is high, which benefits from the high value of the full height/full width at half-maximum and the small step size of the wavelength shift (0.5 nm). Meanwhile, the FPL could be effectively applied as a well-defined model to verify the plasmonic enhancement in surface enhanced Raman scattering. As the FPL is an integrated optical material with graded individual SPR peaks, it can not only be a theoretical model for fundamental research, but also has great potential in high-throughput screening of optical materials, multiplex sensors, etc.
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Bondonno, Catherine P; Blekkenhorst, Lauren C; Prince, Richard L; Ivey, Kerry L; Lewis, Joshua R; Devine, Amanda; Woodman, Richard J; Lundberg, Jon O; Croft, Kevin D; Thompson, Peter L; Hodgson, Jonathan M
2017-07-01
A short-term increase in dietary nitrate (NO 3 - ) improves markers of vascular health via formation of nitric oxide and other bioactive nitrogen oxides. Whether this translates into long-term vascular disease risk reduction has yet to be examined. We investigated the association of vegetable-derived nitrate intake with common carotid artery intima-media thickness (CCA-IMT), plaque severity, and ischemic cerebrovascular disease events in elderly women (n=1226). Vegetable nitrate intake, lifestyle factors, and cardiovascular disease risk factors were determined at baseline (1998). CCA-IMT and plaque severity were measured using B-mode carotid ultrasound (2001). Complete ischemic cerebrovascular disease hospitalizations or deaths (events) over 14.5 years (15 032 person-years of follow-up) were obtained from the West Australian Data Linkage System. Higher vegetable nitrate intake was associated with a lower maximum CCA-IMT (B=-0.015, P =0.002) and lower mean CCA-IMT (B=-0.012, P =0.006). This relationship remained significant after adjustment for lifestyle and cardiovascular risk factors ( P ≤0.01). Vegetable nitrate intake was not a predictor of plaque severity. In total 186 (15%) women experienced an ischemic cerebrovascular disease event. For every 1 SD (29 mg/d) higher intake of vegetable nitrate, there was an associated 17% lower risk of 14.5-year ischemic cerebrovascular disease events in both unadjusted and fully adjusted models ( P =0.02). Independent of other risk factors, higher vegetable nitrate was associated with a lower CCA-IMT and a lower risk of an ischemic cerebrovascular disease event. © 2017 American Heart Association, Inc.
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TRAIL Enhances Shikonin Induced Apoptosis through ROS/JNK Signaling in Cholangiocarcinoma Cells.
Zhou, Guangyao; Yang, Zuqin; Wang, Xiaodong; Tao, Ran; Zhou, Yuanping
2017-01-01
Cholangiocarcinoma (CCA), arising from varying locations within the biliary tree, is the second most common primary liver malignancy worldwide. Shikonin, an active compound extracted from the Chinese herb Zicao, holds anti-bacterial, anti-inflammatory, and anti-tumor activities. However, the effect of shikonin on human cholangiocarcinoma and detailed mechanisms of TRAIL enhancement remains to be elucidated. The purpose of the study was to investigate the protective functions of TRAIL enhancement for shikonin induced apoptosis in cholangiocarcinoma cells. We use MTT assay, apoptosis assay, caspase activity assay, flow cytometry assay, real time PCR and Western blot to observe the effects of TRAIL on shikonin induced cholangiocarcinoma cells apoptosis and its mechanism. Shikonin inhibited cell viability and induced apoptosis of CCA cells, effects enhanced by TRAIL treatment via activation of caspase-3, -8, -9. Furhermore, TRAIL enhanced anti-proliferation of shikonin and shikonin induced apoptosis through induction of ROS mediated JNK activation, while AKT activation had an effect on shikonin anti-proliferation activity, but not in the TRAIL enhanced counterparts. Finally, shikonin upregulated DR5 expression, an effect essential for TRAIL-enhanced activities of shikonin in RBE cells. Our results revealed that shikonin could inhibit cells viability and induce apoptosis of CCA cells, effects enhanced by TRAIL treatment via ROS mediated JNK signalling pathways, involving up-regulation of DR5 expression. Our results provide further insight into the mechanism underlying the anti-tumor effects of shikonin by TRAIL enhanced in CCA and a new therapeutic strategy to CCA treatment. © 2017 The Author(s). Published by S. Karger AG, Basel.
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Biomarkers for the Diagnosis of Cholangiocarcinoma: A Systematic Review.
Tshering, Gyem; Dorji, Palden Wangyel; Chaijaroenkul, Wanna; Na-Bangchang, Kesara
2018-06-01
Cholangiocarcinoma (CCA), a malignant tumor of the bile duct, is a major public health problem in many Southeast Asian countries, particularly Thailand. The slow progression makes it difficult for early diagnosis and most patients are detected in advanced stages. This study aimed to review all relevant articles related to the biomarkers for the diagnosis of CCA and point out potential biomarkers. A thorough search was performed in PubMed and ScienceDirect for CCA biomarker articles. Required data were extracted. A total of 46 articles that fulfilled the inclusion and had none of the exclusion criteria were included in the analysis (17, 22, 3, 4, and 1 articles on blood, tissue, bile, both blood and tissue, and urine biomarkers, respectively). Carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA), either alone or in combination with other biomarkers, are the most commonly studied biomarkers in the serum. Their sensitivity and specificity ranged from 47.2% to 98.2% and 89.7% to 100%, respectively. However, in the tissue, gene methylations and DNA-related markers were the most studied CCA biomarkers. Their sensitivity and specificity ranged from 58% to 87% and 98% to 100%, respectively. Some articles investigated biomarkers both in blood and tissues, particularly CA19-9 and CEA, with sensitivity and specificity ranging from 33% to 100% and 50% to 97.7%, respectively. Although quite a number of biomarkers with a potential role in the early detection of CCA have been established, it is difficult to single out any particular marker that could be used in the routine clinical settings.
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Wurm; Blum
2000-01-20
We experimentally studied the shape of dust grains grown in a cluster-cluster type of aggregation (CCA) and derived characteristic axial ratios to describe the nonsphericity. CCAs might be described by an axial ratio rhoCCA=rg,max&solm0;rg,min approximately 2.0 in the limit of large aggregates, where rg,min and rg,max describe the minimum and maximum radius of gyration, while small aggregates show a somewhat larger value in their mean axial ratio up to rhoCCA approximately 3.0 but rapidly decrease to the limit rhoCCA approximately 2.0. The axial ratios for large aggregates are in agreement with the general findings of different authors for axial ratios of interstellar dust grains that are generally described by rods or spheroids. Beyond this kind of agreement, our approach does not necessarily require a special shape for individual dust grains but rather offers a physical process to generate nonsphericity. Although the simple shapes might be sufficient for first-order applications and are easier to handle analytically, our results offer a firm ground of special axial ratios for rods or spheroids on a more physical basis apart from any ad hoc assumptions. We also find an alignment of the aggregates during sedimentation in a gas along the drift axis leading to an axial ratio of rhoCCA,align=1.21+/-0.02 with respect to the drift axis and an axis perpendicular to this drift. This result is directly applicable to dust grains in protoplanetary disks and planetary atmospheres.
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NASA Astrophysics Data System (ADS)
Cooper, H.; Paytan, A.; Potts, D. C.
2014-12-01
Anthropogenic carbon dioxide dissolving into the world's oceans is causing a profound and rapid shift in ocean chemistry referred to as ocean acidification (OA) that causes carbonate structures to dissolve more readily in seawater with negative effects for organisms relying on calcified skeletons or shells (e.g. corals, mollusks, coralline algae). Crustose coralline algae (CCA) are ubiquitous and essential on coral reefs, providing both ecological and structural benefits to the reefs. However, CCA are adversely affected by low pH water, with severe reductions in recruitment, survival, growth and productivity. The ability of different species of CCA to adapt to low pH waters was tested using a system of natural submarine springs (called "ojos") near Puerto Morelos on the Yucatan Peninsula, Mexico. These ojos continuously discharge groundwater that is close to seawater salinity but more acidic (pH 6.70-7.30) and under saturated (0.3 Ω to 0.97 Ω) than the ambient seawater (pH 8.03, 3.60 Ω ). Both corals and coralline algae grow in the water from these springs, suggesting that some calcifying species differ in their tolerance to low pH waters. Corallines were sampled along a pH gradient at five springs in December 2013 using underwater transects. Differences in percent cover, species abundance and diversity of CCA by pH levels will be discussed. This work utilizes a unique natural laboratory for studying properties of calcifying biota along pH gradients and provides insight into the ability of CCA to tolerate or adapt to future conditions.
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Kunkeaw, Nawapol; Jeon, Sung Ho; Lee, Kwanbok; Johnson, Betty H.; Tanasanvimon, Suebpong; Javle, Milind; Pairojkul, Chawalit; Chamgramol, Yaovalux; Wongfieng, Wipaporn; Gong, Bin; Leelayuwat, Chanvit; Lee, Yong Sun
2013-01-01
We have recently identified nc886 (pre-miR-886 or vtRNA2-1) as a novel type of non-coding RNA that inhibits activation of PKR (Protein Kinase RNA-activated). PKR's pro-apoptotic role through eIF2α phosphorylation is well established in the host defense against viral infection. Paradoxically, some cancer patients have elevated PKR activity; however, its cause and consequence are not understood. Initially we evaluated the expression of nc886, PKR and eIF2α in non-malignant cholangiocyte and cholangiocarcinoma (CCA) cells. nc886 is repressed in CCA cells and this repression is the cause of PKR's activation therein. nc886 alone is necessary and sufficient for suppression of PKR via direct physical interaction. Consistently, artificial suppression of nc886 in cholangiocyte cells activates the canonical PKR/eIF2α cell death pathway, suggesting a potential significance of the nc886 suppression and the consequent PKR activation in eliminating pre-malignant cells during tumorigenesis. In comparison, active PKR in CCA cells does not induce phospho-eIF2α nor apoptosis, but promotes the pro-survival NF-κB pathway. Thus, PKR plays a dual life or death role during tumorigenesis. Similarly to the CCA cell lines, nc886 tends to be decreased but PKR tends to be activated in our clinical samples from CCA patients. Collectively from our data, we propose a tumor surveillance model for nc886's role in the PKR pathway during tumorigenesis. PMID:22926522
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Price, Nichole
2010-07-01
Habitat selection can determine the distribution and performance of individuals if the precision with which sites are chosen corresponds with exposure to risks or resources. Contrastingly, facilitation can allow persistence of individuals arriving by chance and potentially maladapted to local abiotic conditions. For marine organisms, selection of a permanent attachment site at the end of their larval stage or the presence of a facilitator can be a critical determinant of recruitment success. In coral reef ecosystems, it is well known that settling planula larvae of reef-building corals use coarse environmental cues (i.e., light) for habitat selection. Although laboratory studies suggest that larvae can also use precise biotic cues produced by crustose coralline algae (CCA) to select attachment sites, the ecological consequences of biotic cues for corals are poorly understood in situ. In a field experiment exploring the relative importance of biotic cues and variability in habitat quality to recruitment of hard corals, pocilloporid and acroporid corals recruited more frequently to one species of CCA, Titanoderma prototypum, and significantly less so to other species of CCA; these results are consistent with laboratory assays from other studies. The provision of the biotic cue accurately predicted coral recruitment rates across habitats of varying quality. At the scale of CCA, corals attached to the "preferred" CCA experienced increased survivorship while recruits attached elsewhere had lower colony growth and survivorship. For reef-building corals, the behavioral selection of habitat using chemical cues both reduces the risk of incidental mortality and indicates the presence of a facilitator.
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The linkage between geopotential height and monthly precipitation in Iran
NASA Astrophysics Data System (ADS)
Shirvani, Amin; Fadaei, Amir Sabetan; Landman, Willem A.
2018-04-01
This paper investigates the linkage between large-scale atmospheric circulation and monthly precipitation during November to April over Iran. Canonical correlation analysis (CCA) is used to set up the statistical linkage between the 850 hPa geopotential height large-scale circulation and monthly precipitation over Iran for the period 1968-2010. The monthly precipitation dataset for 50 synoptic stations distributed in different climate regions of Iran is considered as the response variable in the CCA. The monthly geopotential height reanalysis dataset over an area between 10° N and 60° N and from 20° E to 80° E is utilized as the explanatory variable in the CCA. Principal component analysis (PCA) as a pre-filter is used for data reduction for both explanatory and response variables before applying CCA. The optimal number of principal components and canonical variables to be retained in the CCA equations is determined using the highest average cross-validated Kendall's tau value. The 850 hPa geopotential height pattern over the Red Sea, Saudi Arabia, and Persian Gulf is found to be the major pattern related to Iranian monthly precipitation. The Pearson correlation between the area averaged of the observed and predicted precipitation over the study area for Jan, Feb, March, April, November, and December months are statistically significant at the 5% significance level and are 0.78, 0.80, 0.82, 0.74, 0.79, and 0.61, respectively. The relative operating characteristic (ROC) indicates that the highest scores for the above- and below-normal precipitation categories are, respectively, for February and April and the lowest scores found for December.
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Kim, Jae-Young; Kim, Tae-Sung; Eom, In-Yong; Kang, Sung Mo; Cho, Tae-Su; Choi, In Gyu; Choi, Joon Weon
2012-08-15
In this study, chromated copper arsenate-treated wood (CCA-W) and alkaline copper quaternary compounds-treated wood (ACQ-W) were subjected to fast pyrolysis at 500°C for ca. 2s to produce bio-oil and char. The physicochemical properties of the pyrolytic products as well as the distribution of heavy metals - arsenic, copper and chrome - during fast pyrolysis were investigated. The water content, viscosity, pH and higher heating value (HHV) of bio-oil from CCA-W were 24.8 wt%, 13.5 cSt, 2.1 and 16 MJ/kg, respectively, whereas those of bio-oil from ACQ-W were 27.9 wt%, 16 cSt, 3.0 and 14.1 MJ/kg, respectively. The yields of bio-oil from CCA-W and ACQ-W were 43.3% and 46.6%, respectively, significantly lower than that of control (61.6%). In the pyrolytic products of CCA-W, the concentrations of arsenic, copper and chromium were determined to be 36.4 wt%, 74.0 wt% and 75.4 wt% in char, respectively, 34.5 wt%, 10.3 wt% and 9.0 wt% in bio-oil, respectively, and 29.0 wt%, 15.7 wt% and 15.5 wt% in gas, respectively. In addition, most of the copper appeared in the char (98.8 wt%) and only a trace amount of copper was detected in the bio-oil (0.2 wt%) produced by ACQ-W. Copyright © 2012 Elsevier B.V. All rights reserved.
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Grüneis, Heidelinde; Penker, Marianne; Höferl, Karl-Michael
2016-01-01
Our scientific view on climate change adaptation (CCA) is unsatisfying in many ways: It is often dominated by a modernistic perspective of planned pro-active adaptation, with a selective focus on measures directly responding to climate change impacts and thus it is far from real-life conditions of those who are actually affected by climate change. Farmers have to simultaneously adapt to multiple changes. Therefore, also empirical climate change adaptation research needs a more integrative perspective on real-life climate change adaptations. This also has to consider "hidden" adaptations, which are not explicitly and directly motivated by CCA but actually contribute to the sector's adaptability to climate change. The aim of the present study is to develop and test an analytic framework that contributes to a broader understanding of CCA and to bridge the gap between scientific expertise and practical action. The framework distinguishes three types of CCA according to their climate related motivations: explicit adaptations, multi-purpose adaptations, and hidden adaptations. Although agriculture is among the sectors that are most affected by climate change, results from the case study of Tyrolean mountain agriculture show that climate change is ranked behind other more pressing "real-life-challenges" such as changing agricultural policies or market conditions. We identified numerous hidden adaptations which make a valuable contribution when dealing with climate change impacts. We conclude that these hidden adaptations have not only to be considered to get an integrative und more realistic view on CCA; they also provide a great opportunity for linking adaptation strategies to farmers' realities.
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Correa, Nicolle M; Li, Yi-Ou; Adalı, Tülay; Calhoun, Vince D
2008-12-01
Typically data acquired through imaging techniques such as functional magnetic resonance imaging (fMRI), structural MRI (sMRI), and electroencephalography (EEG) are analyzed separately. However, fusing information from such complementary modalities promises to provide additional insight into connectivity across brain networks and changes due to disease. We propose a data fusion scheme at the feature level using canonical correlation analysis (CCA) to determine inter-subject covariations across modalities. As we show both with simulation results and application to real data, multimodal CCA (mCCA) proves to be a flexible and powerful method for discovering associations among various data types. We demonstrate the versatility of the method with application to two datasets, an fMRI and EEG, and an fMRI and sMRI dataset, both collected from patients diagnosed with schizophrenia and healthy controls. CCA results for fMRI and EEG data collected for an auditory oddball task reveal associations of the temporal and motor areas with the N2 and P3 peaks. For the application to fMRI and sMRI data collected for an auditory sensorimotor task, CCA results show an interesting joint relationship between fMRI and gray matter, with patients with schizophrenia showing more functional activity in motor areas and less activity in temporal areas associated with less gray matter as compared to healthy controls. Additionally, we compare our scheme with an independent component analysis based fusion method, joint-ICA that has proven useful for such a study and note that the two methods provide complementary perspectives on data fusion.
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Nanoscale lateral displacement arrays for the separation of exosomes and colloids down to 20 nm
NASA Astrophysics Data System (ADS)
Austin, Robert; Wunsch, Benjamin; Smith, Joshua; Gifford, Stacey; Wang, Chao; Brink, Markus; Bruce, Robert; Stolovitzky, Gustavo; Astier, Yann
Deterministic lateral displacement (DLD) pillar arrays are an efficient technology to sort, separate and enrich micrometre-scale particles, which include parasites1, bacteria2, blood cells3 and circulating tumour cells in blood4. However, this technology has not been translated to the true nanoscale, where it could function on biocolloids, such as exosomes. Exosomes, a key target of liquid biopsies, are secreted by cells and contain nucleic acid and protein information about their originating tissue5. One challenge in the study of exosome biology is to sort exosomes by size and surface markers6, 7. We use manufacturable silicon processes to produce nanoscale DLD (nano-DLD) arrays of uniform gap sizes ranging from 25 to 235 nm. We show that at low Péclet (Pe) numbers, at which diffusion and deterministic displacement compete, nano-DLD arrays separate particles between 20 to 110 nm based on size with sharp resolution. Further, we demonstrate the size-based displacement of exosomes, and so open up the potential for on-chip sorting and quantification of these important biocolloids.
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Nanoscale lateral displacement arrays for the separation of exosomes and colloids down to 20 nm
NASA Astrophysics Data System (ADS)
Wunsch, Benjamin H.; Smith, Joshua T.; Gifford, Stacey M.; Wang, Chao; Brink, Markus; Bruce, Robert L.; Austin, Robert H.; Stolovitzky, Gustavo; Astier, Yann
2016-11-01
Deterministic lateral displacement (DLD) pillar arrays are an efficient technology to sort, separate and enrich micrometre-scale particles, which include parasites, bacteria, blood cells and circulating tumour cells in blood. However, this technology has not been translated to the true nanoscale, where it could function on biocolloids, such as exosomes. Exosomes, a key target of 'liquid biopsies', are secreted by cells and contain nucleic acid and protein information about their originating tissue. One challenge in the study of exosome biology is to sort exosomes by size and surface markers. We use manufacturable silicon processes to produce nanoscale DLD (nano-DLD) arrays of uniform gap sizes ranging from 25 to 235 nm. We show that at low Péclet (Pe) numbers, at which diffusion and deterministic displacement compete, nano-DLD arrays separate particles between 20 to 110 nm based on size with sharp resolution. Further, we demonstrate the size-based displacement of exosomes, and so open up the potential for on-chip sorting and quantification of these important biocolloids.
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High-Throughput Fabrication of Ultradense Annular Nanogap Arrays for Plasmon-Enhanced Spectroscopy.
Cai, Hongbing; Meng, Qiushi; Zhao, Hui; Li, Mingling; Dai, Yanmeng; Lin, Yue; Ding, Huaiyi; Pan, Nan; Tian, Yangchao; Luo, Yi; Wang, Xiaoping
2018-06-13
The confinement of light into nanometer-sized metallic nanogaps can lead to an extremely high field enhancement, resulting in dramatically enhanced absorption, emission, and surface-enhanced Raman scattering (SERS) of molecules embedded in nanogaps. However, low-cost, high-throughput, and reliable fabrication of ultra-high-dense nanogap arrays with precise control of the gap size still remains a challenge. Here, by combining colloidal lithography and atomic layer deposition technique, a reproducible method for fabricating ultra-high-dense arrays of hexagonal close-packed annular nanogaps over large areas is demonstrated. The annular nanogap arrays with a minimum diameter smaller than 100 nm and sub-1 nm gap width have been produced, showing excellent SERS performance with a typical enhancement factor up to 3.1 × 10 6 and a detection limit of 10 -11 M. Moreover, it can also work as a high-quality field enhancement substrate for studying two-dimensional materials, such as MoSe 2 . Our method provides an attractive approach to produce controllable nanogaps for enhanced light-matter interaction at the nanoscale.
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CCA 3101/4101 Environmental Humanities: The History of a Unit through an Ecopedagogical Lens
ERIC Educational Resources Information Center
Ryan, John Charles
2012-01-01
In 2011 the author taught, for the first time, the well-established unit CCA3101/4101 Environmental Humanities in the School of Communications and Arts at ECU (Edith Cowan University) in Western Australia. The unit has a 20-year history through associate professor Rod Giblett and parallels the development of the environmental humanities as a field…
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John J. Janowiak; Robert H. Falk; Brad A. Gething; John A. Tsirigotis
2014-01-01
This study determined the mechanical properties of nail-laminated (nail-lam) posts manufactured from reclaimed chromated copper arsenate (CCA)âtreated decking lumber. Though CCA-treated lumber is no longer accepted for use in residential applications, it is permitted in agricultural and industrial applications where health and environmental impacts are deemed to be...
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The U.S. Environmental Protection Agency has conducted a probabilistic exposure and dose assessment on the arsenic (As) and chromium (Cr) components of Chromated Copper Arsenate (CCA) using the Stochastic Human Exposure and Dose Simulation model for wood preservatives (SHEDS-Wood...
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Effect of moisture content on strength of CCA-treated lumber
Jerrold E. Winandy
1995-01-01
Recent studies on the effects of chromated copper arsenate (CCA) treatment on lumber design properties have primarily evaluated the effects of such treatment at or near 12% moisture content and at failure times of 1 to 10 min. The influence of various moisture contents and faster loading rates is unknown. This report discusses the influence of moisture content and its...
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Adhesive bonding of wood treated with ACQ and copper azole preservatives
Linda F. Lorenz; Charles Frihart
2006-01-01
Treated wood has generally been more difficult to bond than untreated wood for a variety of reasons. Alkaline copper quat (ACQ) and copper azole (CA-B), the most prominent substitutes for chromated copper arsenate (CCA), are difficult to bond consistently. Using a phenol-resorcinol- formaldehyde (PRF) adhesive formulated for bonding to CCA-treated wood, we examined the...
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K. R. Sherrill; M. A. Lefsky; J. B. Bradford; M. G. Ryan
2008-01-01
This study evaluates the relative ability of simple light detection and ranging (lidar) indices (i.e., mean and maximum heights) and statistically derived canonical correlation analysis (CCA) variables attained from discrete-return lidar to estimate forest structure and forest biomass variables for three temperate subalpine forest sites. Both lidar and CCA explanatory...
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K.R. Sherrill; M.A. Lefsky; J.B. Bradford; M.G. Ryan
2008-01-01
This study evaluates the relative ability of simple light detection and ranging (lidar) indices (i.e., mean and maximum heights) and statistically derived canonical correlation analysis (CCA) variables attained from discrete-return lidar to estimate forest structure and forest biomass variables for three temperate subalpine forest sites. Both lidar and CCA explanatory...
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Frederick Green; Carol A. Clausen
2005-01-01
The voluntary withdrawal of chromated copper arsenate (CCA)-treated wood from most residential applications has increased the use of non-arsenical copper-based organic wood preservatives. Because the arsenic component of CCA controlled copper tolerant fungi, scientists have renewed interest in and concern about the decay capacity in the important copper-tolerant group...
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Inadequate redrying linked to dimensional instability of CCA-treated southern pine lumber
Todd F. Shupe; Stan T. Lebow; Elvin T. Choong; Manzhen Xiong
2001-01-01
Some instances of severe warping of siding treated with a commercial waterborne preservative have been reported to the authors. We investigated this problem by evaluating 25mm-, 51 -mm-, and 102-mm- (1-, 2,- and 4-in.-) thick chromated copper arsenate (CCA) treated No. 1 southern yellow pine lumber shipped from three suppliers to a secondary manufacturer in Louisiana....
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Effect of prestain on the release rate of copper, chromium, and arsenic from western hemlock
Stan T. Lebow; James W. Evans
1999-01-01
To enhance appearance, stains are often sprayed onto western hemlock (Tsuga heterophylla (Raf.) Sarg.) lumber prior to treatment with chromated copper arsenate (CCA-C). Recently, concerns have increased that prestaining may affect the rate of leaching of CCA-C components from the treated wood and that leaching data generated with prestained material may not reflect...
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Carol Clausen
2004-01-01
In this study, three possible improvements to a remediation process for chromated-copper-arsenate (CCA) treated wood were evaluated. The process involves two steps: oxalic acid extraction of wood fiber followed by bacterial culture with Bacillus licheniformis CC01. The three potential improvements to the oxalic acid extraction step were (1) reusing oxalic acid for...
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Curcumin up regulates T helper 1 cells in patients with colon cancer.
Xu, Bin; Yu, Lin; Zhao, Li-Zhong
2017-01-01
The therapy for the advanced colon cancer (Cca) is unsatisfactory currently. To regulate the immune effector cell function has shown a positive effect on the treatment of advanced cancers. This study tests a hypothesis that administration with curcumin converts the Cca patient-derived regulatory T cells (Treg) to T helper (Th) 1 cells. In this study, a group of patients with advanced Cca was recruited into this study. The patients were treated with curcumin. The peripheral Tregs and Th1 cells were assessed by flow cytometry. The results showed that, after the curcumin therapy, the forkhead box protein (Foxp) 3 positive Treg frequency was markedly reduced, the frequency of Th1 cells was significantly increased in Cca patients. Treating with curcumin repressed the Foxp3 gene transcription in Tregs; the Tregs were then converted into Th1 cells. The results also revealed that Foxp3 bound T-bet to prevent IFN-γ expression in CD4 + T cells, which was abolished by treating with curcumin. In conclusion, the administration of curcumin can convert Tregs to Th1 cells via repressing Foxp3 expression and enhancing IFN-γ production.
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Monte Carlo Estimation of Absorbed Dose Distributions Obtained from Heterogeneous 106Ru Eye Plaques.
Zaragoza, Francisco J; Eichmann, Marion; Flühs, Dirk; Sauerwein, Wolfgang; Brualla, Lorenzo
2017-09-01
The distribution of the emitter substance in 106 Ru eye plaques is usually assumed to be homogeneous for treatment planning purposes. However, this distribution is never homogeneous, and it widely differs from plaque to plaque due to manufacturing factors. By Monte Carlo simulation of radiation transport, we study the absorbed dose distribution obtained from the specific CCA1364 and CCB1256 106 Ru plaques, whose actual emitter distributions were measured. The idealized, homogeneous CCA and CCB plaques are also simulated. The largest discrepancy in depth dose distribution observed between the heterogeneous and the homogeneous plaques was 7.9 and 23.7% for the CCA and CCB plaques, respectively. In terms of isodose lines, the line referring to 100% of the reference dose penetrates 0.2 and 1.8 mm deeper in the case of heterogeneous CCA and CCB plaques, respectively, with respect to the homogeneous counterpart. The observed differences in absorbed dose distributions obtained from heterogeneous and homogeneous plaques are clinically irrelevant if the plaques are used with a lateral safety margin of at least 2 mm. However, these differences may be relevant if the plaques are used in eccentric positioning.
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Kim, Tong-Soo; Pak, Jhang Ho; Kim, Jong-Bo; Bahk, Young Yil
2016-01-01
Parasitic diseases remain an unarguable public health problem worldwide. Liver fluke Clonorchis sinensis is a high risk pathogenic parasitic helminth which is endemic predominantly in Asian countries, including Korea, China, Taiwan, Vietnam, and the far eastern parts of Russia, and is still actively transmitted. According to the earlier 8th National Survey on the Prevalence of Intestinal Parasitic Infections in 2012, C. sinensis was revealed as the parasite with highest prevalence of 1.86% in general population among all parasite species surveyed in Korea. This fluke is now classified under one of the definite Group 1 human biological agents (carcinogens) by International Agency of Research on Cancer (IARC) along with two other parasites, Opisthorchis viverrini and Schistosoma haematobium. C. sinensis infestation is mainly linked to liver and biliary disorders, especially cholangiocarcinoma (CCA). For the purposes of this mini-review, we will only focus on C. sinensis and review pathogenesis and carcinogenesis of clonorchiasis, disease condition by C. sinensis infestation, and association between C. sinensis infestation and CCA. In this presentation, we briefly consider the current scientific status for progression of CCA by heavy C. sinensis infestation from the food-borne trematode and development of CCA. PMID:27418285
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Roy, Vandana; Shukla, Shailja; Shukla, Piyush Kumar; Rawat, Paresh
2017-01-01
The motion generated at the capturing time of electro-encephalography (EEG) signal leads to the artifacts, which may reduce the quality of obtained information. Existing artifact removal methods use canonical correlation analysis (CCA) for removing artifacts along with ensemble empirical mode decomposition (EEMD) and wavelet transform (WT). A new approach is proposed to further analyse and improve the filtering performance and reduce the filter computation time under highly noisy environment. This new approach of CCA is based on Gaussian elimination method which is used for calculating the correlation coefficients using backslash operation and is designed for EEG signal motion artifact removal. Gaussian elimination is used for solving linear equation to calculate Eigen values which reduces the computation cost of the CCA method. This novel proposed method is tested against currently available artifact removal techniques using EEMD-CCA and wavelet transform. The performance is tested on synthetic and real EEG signal data. The proposed artifact removal technique is evaluated using efficiency matrices such as del signal to noise ratio (DSNR), lambda ( λ ), root mean square error (RMSE), elapsed time, and ROC parameters. The results indicate suitablity of the proposed algorithm for use as a supplement to algorithms currently in use.
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Puthdee, Nattapong; Seubwai, Wunchana; Vaeteewoottacharn, Kulthida; Boonmars, Thidarut; Cha'on, Ubon; Phoomak, Chatchai; Wongkham, Sopit
2017-01-01
Berberine is a natural compound found in several herbs. Anticancer activity of berberine was reported in several cancers, however, little is known regarding the effects of berberine against cholangiocarcinoma (CCA). In this study, the growth inhibitory effects of berberine on CCA cell lines and its molecular mechanisms were explored. Cell growth and cell cycle distribution were examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. The expression levels of cell cycle regulatory proteins were determined by Western blot analysis. Berberine significantly inhibited growth of CCA cell lines in a dose and time dependent fashion. The inhibition was largely attributed to cell cycle arrest at the G1 phase through the reduction of cyclin D1, and cyclin E. Moreover, berberine could reduce the expression and activation of signal transducers and activator of transcription 3 (STAT3) and probably nuclear factor-kappaB (NF-κB) via suppression of extracellular signal-regulated kinase (ERK) 1/2 action. These results highlight the potential of berberine to be a multi-target agent for CCA treatment.
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Face-specific Replacement of Calcite by Amorphous Silica Nanoparticles
NASA Astrophysics Data System (ADS)
Liesegang, M.; Milke, R.; Neusser, G.; Mizaikoff, B.
2016-12-01
Amorphous silica, composed of nanoscale spheres, is an important biomineral, alteration product of silicate rocks on the Earth's surface, and precursor material for stable silicate minerals. Despite constant progress in silica sphere synthesis, fundamental knowledge of natural silica particle interaction and ordering processes leading to colloidal crystals is absent so far. To understand the formation pathways of silica spheres in a geologic environment, we investigated silicified Cretaceous mollusk shell pseudomorphs from Coober Pedy (South Australia) using focused ion beam (FIB)-SEM tomography, petrographic microscopy, µ-XRD, and EMPA. The shells consist of replaced calcite crystals (<2 mm) composed of ordered arrays of uniform, close-packed silica spheres 300 ± 10 nm in size. Concentric layered spheres composed of 40 nm-sized subparticles provide evidence that, at least in the final stage, particle aggregation was the major sphere growth mechanism. Silica sphere arrays in periodically changing orientations perfectly replicate polysynthetic twinning planes of calcite. FIB-SEM tomography shows that cubic closed-packed sphere arrangements preserve the twin lamellae, while the twin plane consists of a submicrometer layer of randomly ordered spheres and vacancies. To transfer crystallographic information from parent to product, the advancement of synchronized dissolution and precipitation fronts along lattice planes is essential. We assume that the volume-preserving replacement process proceeds via a face-specific dissolution-precipitation mechanism with intermediate subparticle aggregation and subsequent layer-by-layer deposition of spheres along a planar surface. Porosity created during the replacement reaction allows permanent fluid access to the propagating reaction interface. Fluid pH and ionic strength remain constant throughout the replacement process, permitting continuous silica nanoparticle formation and diffusion-limited colloid aggregation. Our study provides a natural example of the transformation of an atomic crystal to an amorphous, mesoscale ordered material; thus, links the research fields of natural colloidal crystal formation, carbonate-silica replacement, and crystallization by oriented particle aggregation (CPA).
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Fabrication of bioinspired nanostructured materials via colloidal self-assembly
NASA Astrophysics Data System (ADS)
Huang, Wei-Han
Through millions of years of evolution, nature creates unique structures and materials that exhibit remarkable performance on mechanicals, opticals, and physical properties. For instance, nacre (mother of pearl), bone and tooth show excellent combination of strong minerals and elastic proteins as reinforced materials. Structured butterfly's wing and moth's eye can selectively reflect light or absorb light without dyes. Lotus leaf and cicada's wing are superhydrophobic to prevent water accumulation. The principles of particular biological capabilities, attributed to the highly sophisticated structures with complex hierarchical designs, have been extensively studied. Recently, a large variety of novel materials have been enabled by natural-inspired designs and nanotechnologies. These advanced materials will have huge impact on practical applications. We have utilized bottom-up approaches to fabricate nacre-like nanocomposites with "brick and mortar" structures. First, we used self-assembly processes, including convective self-assembly, dip-coating, and electrophoretic deposition to form well oriented layer structure of synthesized gibbsite (aluminum hydroxide) nanoplatelets. Low viscous monomer was permeated into layered nanoplatelets and followed by photo-curing. Gibbsite-polymer composite displays 2 times higher tensile strength and 3 times higher modulus when compared with pure polymer. More improvement occurred when surface-modified gibbsite platelets were cross-linked with the polymer matrix. We observed ˜4 times higher strength and nearly 1 order of magnitude higher modulus than pure polymer. To further improve the mechanical strength and toughness of inorganicorganic nanocomposites, we exploited ultrastrong graphene oxide (GO), a single atom thick hexagonal carbon sheet with pendant oxidation groups. GO nanocomposite is made by co-filtrating GO/polyvinyl alcohol suspension on 0.2 im pore-sized membrane. It shows ˜2 times higher strength and ˜15 times higher ultimate strains than nacre and pure GO paper (also synthesized by filtration). Specifically, it exhibits ˜30 times higher fracture energy than filtrated graphene paper and nacre, ˜100 times tougher than filtrated GO paper. Besides reinforced nanocomposites, we further explored the self-assembly of spherical colloids and the templating nanofabrication of moth-eye-inspired broadband antireflection coatings. Binary crystalline structures can be easily accomplished by spin-coating double-layer nonclose-packed colloidal crystals as templates, followed by colloidal templating. The polymer matrix between self-assembled colloidal crystal has been used as a sacrificial template to define the resulting periodic binary nanostructures, including intercalated arrays of silica spheres and polymer posts, gold nanohole arrays with binary sizes, and dimple-nipple antireflection coatings. The binary-structured antireflection coatings exhibit better antireflective properties than unitary coatings. Natural optical structures and nanocomposites teach us a great deal on how to create high performance artificial materials. The bottom-up technologies developed in this thesis are scalable and compatible with standard industrial processes, promising for manufacturing high-performance materials for the benefits of human beings.
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NASA Astrophysics Data System (ADS)
Lohmüller, Theobald; Müller, Ulrich; Breisch, Stefanie; Nisch, Wilfried; Rudorf, Ralf; Schuhmann, Wolfgang; Neugebauer, Sebastian; Kaczor, Markus; Linke, Stephan; Lechner, Sebastian; Spatz, Joachim; Stelzle, Martin
2008-11-01
A porous metal-insulator-metal sensor system was developed with the ultimate goal of enhancing the sensitivity of electrochemical sensors by taking advantage of redox cycling of electro active molecules between closely spaced electrodes. The novel fabrication technology is based on thin film deposition in combination with colloidal self-assembly and reactive ion etching to create micro- or nanopores. This cost effective approach is advantageous compared to common interdigitated electrode arrays (IDA) since it does not require high definition lithography technology. Spin-coating and random particle deposition, combined with a new sublimation process are discussed as competing strategies to generate monolayers of colloidal spheres. Metal-insulator-metal layer systems with low leakage currents < 10 pA and an insulator thickness as low as 100 nm were obtained at high yield (typically > 90%). We also discuss possible causes of sensor failure with respect to critical fabrication processes. Short circuits which could occur during or as a result of the pore etching process were investigated in detail. Infrared microscopy in combination with focused ion beam etching/SEM were used to reveal a defect mechanism creating interconnects and increased leakage current between the top and bottom electrodes. Redox cycling provides for amplification factors of >100. A general applicability for electrochemical diagnostic assays is therefore anticipated.
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Okoyo, Collins; Simiyu, Elses; Njenga, Sammy M; Mwandawiro, Charles
2018-04-11
Kato-Katz technique has been the mainstay test in Schistosoma mansoni diagnosis in endemic areas. However, recent studies have documented its poor sensitivity in evaluating Schistosoma mansoni infection especially in areas with lower rates of transmission. It's the primary diagnostic tool in monitoring impact of the Kenya national school based deworming program on infection transmission, but there is need to consider a more sensitive technique as the prevalence reduces. Therefore, this study explored the relationship between results of the stool-based Kato-Katz technique with urine-based point-of-care circulating cathodic antigen (POC-CCA) test in view to inform decision-making by the program in changing from Kato-Katz to POC-CCA test. We used two cross-sectional surveys conducted pre- and post- mass drug administration (MDA) using praziquantel in a representative random sample of children from 18 schools across 11 counties. A total of 1944 children were randomly sampled for the study. Stool and urine samples were tested for S. mansoni infection using Kato-Katz and POC-CCA methods, respectively. S. mansoni prevalence using each technique was calculated and 95% confidence intervals obtained using binomial regression model. Specificity (Sp) and sensitivity (Sn) were determined using 2 × 2 contingency tables and compared using the McNemar's chi-square test. A total of 1899 and 1878 children were surveyed at pre- and post-treatment respectively. S. mansoni infection prevalence was 26.5 and 21.4% during pre- and post-treatment respectively using POC-CCA test, and 4.9 and 1.5% for pre- and post-treatment respectively using Kato-Katz technique. Taking POC-CCA as the gold standard, Kato-Katz was found to have significantly lower sensitivity both at pre- and post-treatment, Sn = 12.5% and Sn = 5.2% respectively, McNemar test χ 2 m = 782.0, p < 0.001. In overall, the results showed a slight/poor agreement between the two methods, kappa index (k) = 0.11, p < 0.001, inter-rater agreement = 77.1%. Results showed POC-CCA technique as an effective, sensitive and accurate screening tool for Schistosoma mansoni infection in areas of low prevalence. It was up to 14-fold accurate than Kato-Katz which had extremely inadequate sensitivity. We recommend usage of POC-CCA alongside Kato-Katz examinations by Schistosomiasis control programs in low prevalence areas.
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ERIC Educational Resources Information Center
Lall, Marie
2011-01-01
In Myanmar schools, rote learning is the norm. International aid and education organisations based in the country have been trying to promote the child centred approach (CCA) as a much more progressive form of teaching and learning. The CCA is being rolled out principally through monastic school networks aided by international and national…
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R. Sam Williams; Stan Lebow; Patricia Lebow
2003-01-01
Wood pressure-treated with chromated copper arsenate (CCA) wood preservative is commonly used for outdoor construction. Oxides of arsenic, copper, and chromium are bound in the wood by a complex series of chemical reactions, but a small percentage of these compounds are gradually released by leaching and weathering. Recent studies suggest that the release of these...
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Stan Lebow; R. Sam Williams; Patricia Lebow
2003-01-01
The release of arsenic from wood pressure-treated with chromated copper arsenate (CCA) can be decreased by application of wood finishes, but little is known about the types of finishes that are best suited for this purpose. This study evaluated the effects of finish water repellent content and ultraviolet (UV) radiation on the release of arsenic, copper, and chromium...
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Stan T. Lebow; Daniel Foster
2005-01-01
A study was conducted to evaluate environmental accumulation and mobility of total copper, chromium, and arsenic adjacent to a chromated-copper-arsenate-(CCA-C-) treated wetland boardwalk. The study was considered a severe test because it included a large volume of treated wood in a site with high annual rainfall. Soil and sediment samples were collected before...
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Chronology of UPR activation in skeletal muscle adaptations to chronic contractile activity
Memme, Jonathan M.; Oliveira, Ashley N.
2016-01-01
The mitochondrial and endoplasmic reticulum unfolded protein responses (UPRmt and UPRER) are important for cellular homeostasis during stimulus-induced increases in protein synthesis. Exercise triggers the synthesis of mitochondrial proteins, regulated in part by peroxisome proliferator activator receptor-γ coactivator 1α (PGC-1α). To investigate the role of the UPR in exercise-induced adaptations, we subjected rats to 3 h of chronic contractile activity (CCA) for 1, 2, 3, 5, or 7 days followed by 3 h of recovery. Mitochondrial biogenesis signaling, through PGC-1α mRNA, increased 14-fold after 1 day of CCA. This resulted in 10–32% increases in cytochrome c oxidase activity, indicative of mitochondrial content, between days 3 and 7, as well as increases in the autophagic degradation of p62 and microtubule-associated proteins 1A/1B light chain 3A (LC3)-II protein. Before these adaptations, the UPRER transcripts activating transcription factor-4, spliced X-box-binding protein 1, and binding immunoglobulin protein were elevated (1.3- to 3.8-fold) at days 1–3, while CCAAT/enhancer-binding protein homologous protein (CHOP) and chaperones binding immunoglobulin protein and heat shock protein (HSP) 70 were elevated at mRNA and protein levels (1.5- to 3.9-fold) at days 1–7 of CCA. The mitochondrial chaperones 10-kDa chaperonin, HSP60, and 75-kDa mitochondrial HSP, the protease ATP-dependent Clp protease proteolytic subunit, and the regulatory protein sirtuin-3 of the UPRmt were concurrently induced 10–80% between days 1 and 7. To test the role of the UPR in CCA-induced remodeling, we treated animals with the endoplasmic reticulum stress suppressor tauroursodeoxycholic acid and subjected them to 2 or 7 days of CCA. Tauroursodeoxycholic acid attenuated CHOP and HSP70 protein induction; however, this failed to impact mitochondrial remodeling. Our data indicate that signaling to the UPR is rapidly activated following acute contractile activity, that this is attenuated with repeated bouts, and that the UPR is involved in chronic adaptations to CCA; however, this appears to be independent of CHOP signaling. PMID:27122157
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Kabashima, Ayano; Hirsova, Petra; Bronk, Steven F; Hernandez, Matthew C; Truty, Mark J; Rizvi, Sumera; Kaufmann, Scott H; Gores, Gregory J
2018-03-08
Myeloid cell leukemia 1 (MCL1), a prosurvival member of the BCL2 protein family, has a pivotal role in human cholangiocarcinoma (CCA) cell survival. We previously reported that fibroblast growth factor receptor (FGFR) signalling mediates MCL1-dependent survival of CCA cells in vitro and in vivo. However, the mode and mechanisms of cell death in this model were not delineated. Human CCA cell lines were treated with the pan-FGFR inhibitor LY2874455 and the mode of cell death examined by several complementary assays. Mitochondrial oxidative metabolism was examined using a XF24 extracellular flux analyser. The efficiency of FGFR inhibition in patient-derived xenografts (PDX) was also assessed. CCA cells expressed two species of MCL1, a full-length form localised to the outer mitochondrial membrane, and an N terminus-truncated species compartmentalised within the mitochondrial matrix. The pan-FGFR inhibitor LY2874455 induced non-apoptotic cell death in the CCA cell lines associated with cellular depletion of both MCL1 species. The cell death was accompanied by failure of mitochondrial oxidative metabolism and was most consistent with necrosis. Enforced expression of N terminus-truncated MCL1 targeted to the mitochondrial matrix, but not full-length MCL1 targeted to the outer mitochondrial membrane, rescued cell death and mitochondrial function. LY2874455 treatment of PDX-bearing mice was associated with tumour cell loss of MCL1 and cell necrosis. FGFR inhibition induces loss of matrix MCL1, resulting in cell necrosis. These observations support a heretofore unidentified, alternative MCL1 survival function, namely prevention of cell necrosis, and have implications for treatment of human CCA. Herein, we report that therapeutic inhibition of a cell receptor expressed by bile duct cancer cells resulted in the loss of a critical survival protein termed MCL1. Cellular depletion of MCL1 resulted in the death of the cancer cells by a process characterised by cell rupture. Cell death by this process can stimulate the immune system and has implications for combination therapy using receptor inhibition with immunotherapy. Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
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Prevalence and determinants of carotid plaque in the cross-sectional REFINE-Reykjavik study
Sturlaugsdottir, Ran; Aspelund, Thor; Bjornsdottir, Gudlaug; Sigurdsson, Sigurdur; Thorsson, Bolli; Eiriksdottir, Gudny; Gudnason, Vilmundur
2016-01-01
Objective Carotid plaque and intima-media thickness are non-invasive arterial markers that are used as surrogate end points for cardiovascular disease. The aim was to assess the prevalence and severity of carotid plaque, and examine its determinant risk factors and their association to the common carotid artery intima-media thickness (CCA-IMT) in a general population. Methods We examined 6524 participants aged 25–69 years in the population-based REFINE (Risk Evaluation For INfarct Estimates)-Reykjavik study. Plaques at the bifurcation and internal carotid arteries were evaluated. Mean CCA-IMT was measured in the near and far walls of the common carotid arteries. Results The prevalence of minimal, moderate and severe plaque was 35.0%, 8.9% and 1.1%, respectively, and the mean CCA-IMT was 0.73 (SD 0.14) mm. Age, sex, smoking and type 2 diabetes mellitus (T2DM) were the strongest risk factors associated with plaque, followed by systolic blood pressure, total cholesterol, body mass index and family history of myocardial infarct. Low educational level was also strongly and independently associated with plaque. CCA-IMT shared the same risk factors except for a non-significant association with T2DM and family history of myocardial infarction (MI). Participants with T2DM had greater plaque prevalence, 2-fold higher in those <50 years and 17–30% greater in age groups 50–54 to 60–64, and more significant plaques (moderate or severe) were the difference in prevalence was 24% in age group 50–54 and ≥60% in older age groups, compared with non-T2DM. Conclusions Carotid plaque and CCA-IMT have mostly common determinants. However, T2DM and family history of MI were associated with plaque but not with CCA-IMT. Greater prevalence and more severe plaques in individuals with T2DM raise the concern that with increasing prevalence of T2DM we may expect an increase in atherosclerosis and its consequences. PMID:27884845
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2012-01-01
Background Chemotherapy of cholangiocarcinoma (CCA), a devastating cancer with increasing worldwide incidence and mortality rates, is largely ineffective. The discovery and development of effective chemotherapeutics is urgently needed. Methods/Design The study aimed at evaluating anticancer activities, toxicity, and pharmacological activities of the curcumin compound (CUR), the crude ethanolic extracts of rhizomes of Zingiber officinale Roscoe (Ginger: ZO) and Atractylodes lancea thung. DC (Khod-Kha-Mao: AL), fruits of Piper chaba Hunt. (De-Plee: PC), and Pra-Sa-Prao-Yhai formulation (a mixture of parts of 18 Thai medicinal plants: PPF) were investigated in animal models. Anti-cholangiocarcinoma (anti-CCA) was assessed using CCA-xenograft nude mouse model. The antihypertensive, analgesic, anti-inflammatory, antipyretic, and anti-ulcer activities and effects on motor coordination were investigated using Rota-rod test, CODA tail-cuff system, writhing and hot plate tests, carrageenan-induced paw edema test, brewer's yeast test, and alcohol-induced gastric ulcer test, respectively. Acute and subacute toxicity tests were performed according to the OECD guideline for testing of chemicals with modification. Results Promising anticancer activity against CCA in nude mouse xenograft model was shown for the ethanolic extract of AL at all oral dose levels (1000, 3000, and 5000 mg/kg body weight) as well as the extracts of ZO, PPF, and CUR compound at the highest dose level (5000, 4000, and 5000 mg/kg body weight, respectively). PC produced no significant anti-CCA activity. Results from acute and subacute toxicity tests both in mice and rats indicate safety profiles of all the test materials in a broad range of dose levels. No significant toxicity except stomach irritation and general CNS depressant signs were observed. Investigation of pharmacological activities of the test materials revealed promising anti-inflammatory (ZO, PPF, and AL), analgesic (CUR and PPF), antipyretic (CUR and AL), antihypertensive (ZO and AL), and anti-ulcer (CUR, ZO, and AL) activities. Conclusion Plants used in Thai traditional medicine for the treatment of various ailments may provide reservoirs of promising candidate chemotherapeutics for the treatment of CCA. PMID:22448640
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2008-07-16
min after addition of binary mixture. Other images are taken (d) after supernatant removal, (e) after ammonia exposure, ( f ) after air-drying and dye...12] J.P. Hoogenboom , D. Derks, P. Vergeer, A. van Blaaderen, J. Chem. Phys. 117 (2002) 11320. [13] A. van Blaaderen, R. Ruel, P. Wiltzius, Nature...Axe, Y. Fujii, Phys. Rev. Lett. 62 (1989) 1524. [19] F . El Azhar, M. Baus, J.P. Ryekaert, E.J. Meijer, J. Chem. Phys. 112 (2000) 5121. [20] M.S
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Focusing light through dynamical samples using fast continuous wavefront optimization.
Blochet, B; Bourdieu, L; Gigan, S
2017-12-01
We describe a fast continuous optimization wavefront shaping system able to focus light through dynamic scattering media. A micro-electro-mechanical system-based spatial light modulator, a fast photodetector, and field programmable gate array electronics are combined to implement a continuous optimization of a wavefront with a single-mode optimization rate of 4.1 kHz. The system performances are demonstrated by focusing light through colloidal solutions of TiO 2 particles in glycerol with tunable temporal stability.
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Light-assisted, templated self-assembly using a photonic-crystal slab.
Jaquay, Eric; Martínez, Luis Javier; Mejia, Camilo A; Povinelli, Michelle L
2013-05-08
We experimentally demonstrate the technique of light-assisted, templated self-assembly (LATS). We excite a guided-resonance mode of a photonic-crystal slab with 1.55 μm laser light to create an array of optical traps. We demonstrate assembly of a square lattice of 520 nm diameter polystyrene particles spaced by 860 nm. Our results demonstrate how LATS can be used to fabricate reconfigurable structures with symmetries different from traditional colloidal self-assembly, which is limited by free energetic constraints.
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Formation of Ordered and Disordered Dielectric/metal Nanowire Arrays and their Plasmonic Behavior
2007-01-01
sheath geometry. 2. EXPERIMENTAL PROCEDURES Several different nanowire systems have been grown, including random Ga2O3 nanowires, InAs...nanowires, ZnO nanowires, as well as Au lines produced by e-beam lithography. The growth of the Ga2O3 nanowires was achieved by the controlled oxidation...CLOSELY-SPACED PARALLEL ZnO NANOWIRES AND CROSSED Ga2O3 NANOWIRES. As discussed above, due to the far separation of the gold colloid catalyst in the
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Steenackers, Ward; Corneillie, Sander; Araújo, Pedro; Viaene, Tom; Nowack, Moritz K.; Blakeslee, Joshua J.; Novák, Ondřej; Zažímalová, Eva
2017-01-01
Auxin steers numerous physiological processes in plants, making the tight control of its endogenous levels and spatiotemporal distribution a necessity. This regulation is achieved by different mechanisms, including auxin biosynthesis, metabolic conversions, degradation, and transport. Here, we introduce cis-cinnamic acid (c-CA) as a novel and unique addition to a small group of endogenous molecules affecting in planta auxin concentrations. c-CA is the photo-isomerization product of the phenylpropanoid pathway intermediate trans-CA (t-CA). When grown on c-CA-containing medium, an evolutionary diverse set of plant species were shown to exhibit phenotypes characteristic for high auxin levels, including inhibition of primary root growth, induction of root hairs, and promotion of adventitious and lateral rooting. By molecular docking and receptor binding assays, we showed that c-CA itself is neither an auxin nor an anti-auxin, and auxin profiling data revealed that c-CA does not significantly interfere with auxin biosynthesis. Single cell-based auxin accumulation assays showed that c-CA, and not t-CA, is a potent inhibitor of auxin efflux. Auxin signaling reporters detected changes in spatiotemporal distribution of the auxin response along the root of c-CA-treated plants, and long-distance auxin transport assays showed no inhibition of rootward auxin transport. Overall, these results suggest that the phenotypes of c-CA-treated plants are the consequence of a local change in auxin accumulation, induced by the inhibition of auxin efflux. This work reveals a novel mechanism how plants may regulate auxin levels and adds a novel, naturally occurring molecule to the chemical toolbox for the studies of auxin homeostasis. PMID:27837086
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Dokumcu, Zafer; Ergun, Orkan; Celik, Handan Ak; Aydemir, Sohret; Sezak, Murat; Ozok, Geylani; Celik, Ahmet
2008-11-01
Clostridial collagenase A (CCA) has been shown effective in degrading collagen in eschar tissue and promoting healing in partial-thickness burns. As there are also reports of fever, leukocytosis, increased C-reactive protein (CRP) levels and septic complications during treatment with CCA, we aimed to determine in rats whether CCA aggravates the systemic inflammatory response. Rats with partial-thickness burns were randomly divided into groups with either no dressing (ND), povidone-iodine dressing (PID) or CCA dressing (CCAD). Body weights and temperatures, blood leukocyte counts, and serum levels of CRP, interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha), were measured at 0, 3, and 24h and days 3 and 7 from burn. Wounds were cultured on days 1, 3 and 7 and burn depth was evaluated on day 1. Body weights for all groups were significantly lower after burn, with highest loss (25.5%) in the CCAD group. At 3h a significant drop in rectal temperature was noted in all groups. The CCAD group had higher rectal temperature levels than the PID group on days 3 and 7 (p<0.05). Changes in serum levels of CRP, IL-1 beta, IL-6 and TNF-alpha were not significant in the ND and PID groups; the CCAD group showed a significant rise in serum levels of CRP on day 1, of IL-6 on day 3 and of TNF-alpha on day 7. Wound infection was more common in CCAD group and increased on days 3 and 7, but this was insignificant. CCA aggravated the systemic inflammatory response in rats with partial-thickness burns, which is accompanied by a higher risk of infection.